Search results for: natural language processing
325 Decoding Kinematic Characteristics of Finger Movement from Electrocorticography Using Classical Methods and Deep Convolutional Neural Networks
Authors: Ksenia Volkova, Artur Petrosyan, Ignatii Dubyshkin, Alexei Ossadtchi
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Brain-computer interfaces are a growing research field producing many implementations that find use in different fields and are used for research and practical purposes. Despite the popularity of the implementations using non-invasive neuroimaging methods, radical improvement of the state channel bandwidth and, thus, decoding accuracy is only possible by using invasive techniques. Electrocorticography (ECoG) is a minimally invasive neuroimaging method that provides highly informative brain activity signals, effective analysis of which requires the use of machine learning methods that are able to learn representations of complex patterns. Deep learning is a family of machine learning algorithms that allow learning representations of data with multiple levels of abstraction. This study explores the potential of deep learning approaches for ECoG processing, decoding movement intentions and the perception of proprioceptive information. To obtain synchronous recording of kinematic movement characteristics and corresponding electrical brain activity, a series of experiments were carried out, during which subjects performed finger movements at their own pace. Finger movements were recorded with a three-axis accelerometer, while ECoG was synchronously registered from the electrode strips that were implanted over the contralateral sensorimotor cortex. Then, multichannel ECoG signals were used to track finger movement trajectory characterized by accelerometer signal. This process was carried out both causally and non-causally, using different position of the ECoG data segment with respect to the accelerometer data stream. The recorded data was split into training and testing sets, containing continuous non-overlapping fragments of the multichannel ECoG. A deep convolutional neural network was implemented and trained, using 1-second segments of ECoG data from the training dataset as input. To assess the decoding accuracy, correlation coefficient r between the output of the model and the accelerometer readings was computed. After optimization of hyperparameters and training, the deep learning model allowed reasonably accurate causal decoding of finger movement with correlation coefficient r = 0.8. In contrast, the classical Wiener-filter like approach was able to achieve only 0.56 in the causal decoding mode. In the noncausal case, the traditional approach reached the accuracy of r = 0.69, which may be due to the presence of additional proprioceptive information. This result demonstrates that the deep neural network was able to effectively find a representation of the complex top-down information related to the actual movement rather than proprioception. The sensitivity analysis shows physiologically plausible pictures of the extent to which individual features (channel, wavelet subband) are utilized during the decoding procedure. In conclusion, the results of this study have demonstrated that a combination of a minimally invasive neuroimaging technique such as ECoG and advanced machine learning approaches allows decoding motion with high accuracy. Such setup provides means for control of devices with a large number of degrees of freedom as well as exploratory studies of the complex neural processes underlying movement execution.Keywords: brain-computer interface, deep learning, ECoG, movement decoding, sensorimotor cortex
Procedia PDF Downloads 178324 In vitro Antioxidant Activity and Total Phenolic Content of Dillenia indica and Garcinia penducalata, Commonly Used Fruits in Assamese Cuisine
Authors: M. Das, B. P. Sarma, G. Ahmed
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Human diet can be a major source of antioxidants. Poly¬phenols, which are organic compounds present in the regular human diet, have good antioxidant property. Most of the diseases are detected too late and that cause irre¬versible damage to the body. Therefore food that forms the natural source of antioxidants can prevent free radi¬cals from damaging our body tissues. Dillenia indica and Garcinia penducalata are two major fruits, easily available in Assam, North eastern Indian state. In the present study, the in vitro antioxi¬dant properties of the fruits of these plants are compared as the decoction of these fruits form a major part of Assamese cuisine. DPPH free radical scavenging activity of the methanol, petroleum ether and water extracts of G. penducalata and D. indica fruits were carried out by the methods of Cotelle A et al. (1996). Different concentrations ranging from 10–110 ug/ml of the extracts were added to 100 uM of DPPH (2,2, Diphenyl-2-picryl hydrazyl) and the absor¬bance was read at 517 nm after incubation. Ascorbic acid was used as the standard. Different concentrations of the methanol, petroleum ether and water extracts of G. penducalata and D. indica fruits were mixed with sodium nitroprusside and incubated. Griess reagent was added to the mixtures and their optical density was read at 546 nm following the method of Marcocci et al. (1994). Ascorbic acid was used as the standard. In order to find the scavenging activity of the extracts against hydroxyl radicals, the method of Kunchandy & Ohkawa (1990) was followed.The superoxide scavenging activity of the methanol, petroleum ether and water extracts of the fruits was deter¬mined by the method of Robak & Gryglewski (1998).Six replicates were maintained in each of the experiments and their SEM was evaluated based on which, non linear regres¬sion (curve fit), exponential growth were derived to calculate the IC50 values of the SAWE and standard compounds. All the statistical analyses were done by using paired t test. The hydroxyl radical scavenging activity of the various extracts of D. indica exhibited IC50 values < 110 ug/ml concentration, the scavenging activity of the extracts of G. penducalata was surprisingly>110 ug/ml.Similarly the oxygen free radical scavenging activity of the different extracts of D. indica exhibited an IC50 value of <110 ug/ml but the methanolic extract of the same exhib¬ited a better free radical scavenging activity compared to that of vitamin C. The methanolic extract of D. indica exhibited an IC50 value better than that of vitamin C. The DPPH scavenging activities of the various extracts of D. indica and G. penducalata were <110 ug/ml but the methanolic extract of D. indica exhibited an IC50 value bet¬ter than that of vitaminc C.The higher amounts of phenolic content in the methanolic extract of D. indica might be one of the major causes for its enhanced in vitro antioxidant activity.The present study concludes that Dillenia indica and Garcinia penducalata both possesses anti oxidant activi¬ties. The anti oxidant activity of Dillenia indica is superior to that of Garcinia penducalata due to its higher phenolic contentKeywords: antioxidants, free radicals, phenolic, scavenging
Procedia PDF Downloads 595323 Population Diversity of Dalmatian Pyrethrum Based on Pyrethrin Content and Composition
Authors: Filip Varga, Nina Jeran, Martina Biosic, Zlatko Satovic, Martina Grdisa
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Dalmatian pyrethrum (Tanacetum cinerariifolium /Trevir./ Sch. Bip.), a species endemic to the eastern Adriatic coastline, is the source of natural insecticide pyrethrin. Pyrethrin is a mixture of six compounds (pyrethrin I and II, cinerin I and II, jasmolin I and II) that exhibits high insecticidal activity with no detrimental effects to the environment. A recently optimized matrix-solid phase dispersion method (MSPD), using florisil as the sorbent, acetone-ethyl acetate (1:1, v/v) as the elution solvent, and sodium sulfate anhydrous as the drying agent was utilized to extract the pyrethrins from 10 wild populations (20 individuals per population) distributed along the Croatian coast. All six components in the extracts were qualitatively and quantitatively determined by high-performance liquid chromatography with a diode array detector (HPLC-DAD). Pearson’s correlation index was calculated between pyrethrin compounds, and differences between the populations using the analysis of variance were tested. Additionally, the correlation of each pyrethrin component with spatio-ecological variables (bioclimate, soil properties, elevation, solar radiation, and distance from the coastline) was calculated. Total pyrethrin content ranged from 0.10% to 1.35% of dry flower weight, averaging 0.58% across all individuals. Analysis of variance revealed significant differences between populations based on all six pyrethrin compounds and total pyrethrin content. On average, the lowest total pyrethrin content was found in the population from Pelješac peninsula (0.22% of dry flower weight) in which total pyrethrin content lower than 0.18% was detected in 55% of the individuals. The highest average total pyrethrin content was observed in the population from island Zlarin (0.87% of dry flower weight), in which total pyrethrin content higher than 1.00% was recorded in only 30% of the individuals. Pyrethrin I/pyrethrin II ratio as a measure of extract quality ranged from 0.21 (population from the island Čiovo) to 5.88 (population from island Mali Lošinj) with an average of 1.77 across all individuals. By far, the lowest quality of extracts was found in the population from Mt. Biokovo (pyrethrin I/II ratio lower than 0.72 in 40% of individuals) due to the high pyrethrin II content typical for this population. Pearson’s correlation index revealed a highly significant positive correlation between pyrethrin I content and total pyrethrin content and a strong negative correlation between pyrethrin I and pyrethrin II. The results of this research clearly indicate high intra- and interpopulation diversity of Dalmatian pyrethrum with regards to pyrethrin content and composition. The information obtained has potential use in plant genetic resources conservation and biodiversity monitoring. Possibly the largest potential lies in designing breeding programs aimed at increasing pyrethrin content in commercial breeding lines and reintroduction in agriculture in Croatia. Acknowledgment: This work has been fully supported by the Croatian Science Foundation under the project ‘Genetic background of Dalmatian pyrethrum (Tanacetum cinerariifolium /Trevir/ Sch. Bip.) insecticidal potential’ - (PyrDiv) (IP-06-2016-9034).Keywords: Dalmatian pyrethrum, HPLC, MSPD, pyrethrin
Procedia PDF Downloads 144322 COVID-19: Potential Effects of Nutritional Factors on Inflammation Relief
Authors: Maryam Nazari
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COVID-19 is a respiratory disease triggered by the novel coronavirus, SARS-CoV-2, that has reached pandemic status today. Acute inflammation and immune cells infiltration into lung injuries result in multi-organ failure. The presence of other non-communicable diseases (NCDs) with systemic inflammation derived from COVID-19 may exacerbate the patient's situation and increase the risk for adverse effects and mortality. This pandemic is a novel situation and the scientific community at this time is looking for vaccines or drugs to treat the pathology. One of the biggest challenges is focused on reducing inflammation without compromising the correct immune response of the patient. In this regard, addressing the nutritional factors should not be overlooked not only as a matter of avoiding the presence of NCDs with severe infections but also as an adjunctive way to modulate the inflammatory status of the patients. Despite the pivotal role of nutrition in modifying immune response, due to the novelty of the COVID-19 disease, information about the effects of specific dietary agents is limited in this area. From the macronutrients point of view, protein deficiency (quantity or quality) has negative effects on the number of functional immunoglobulins and gut-associated lymphoid tissue (GALT). High biological value proteins or some amino acids like arginine and glutamine are well known for their ability to augment the immune system. Among lipids, fish oil has the ability to inactivate enveloped viruses, suppress pro-inflammatory prostaglandin production and block platelet-activating factors and their receptors. In addition, protectin D1, which is an Omega-3 PUFAs derivation, is a novel antiviral drug. So it seems that these fatty acids can reduce the severity and/or improve recovery of patients with COVID-19. Carbohydrates with lower glycemic index and fibers are associated with lower levels of inflammatory cytokines (CRP, TNF-α, and IL-6). Short-Chain Fatty acids not only exert a direct anti-inflammatory effect but also provide appropriate gut microbial, which is important in gastrointestinal issues related to COVID-19. From the micronutrients point of view, Vitamins A, C, D, E, iron, magnesium, zinc, selenium and copper play a vital role in the maintenance of immune function. Inadequate status in these nutrients may result in decreased resistance against COVID-19 infection. There are specific bioactive compounds in the diet that interact with the ACE2 receptor, which is the gateway for SARS and SARS-CoV-2, and thus controls the viral infection. Regarding this, the potential benefits of probiotics, resveratrol (a polyphenol found in grape), oleoylethanolamide (derived from oleic acid), and natural peroxisome proliferator-activated receptor γ agonists in foodstuffs (like curcumin, pomegranate, hot pepper) are suggested. Yet, it should be pointed out that most of these results have been reported in animal models and further human studies are needed to be verified.Keywords: Covid-19, inflammation, nutrition, dietary agents
Procedia PDF Downloads 174321 Radish Sprout Growth Dependency on LED Color in Plant Factory Experiment
Authors: Tatsuya Kasuga, Hidehisa Shimada, Kimio Oguchi
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Recent rapid progress in ICT (Information and Communication Technology) has advanced the penetration of sensor networks (SNs) and their attractive applications. Agriculture is one of the fields well able to benefit from ICT. Plant factories control several parameters related to plant growth in closed areas such as air temperature, humidity, water, culture medium concentration, and artificial lighting by using computers and AI (Artificial Intelligence) is being researched in order to obtain stable and safe production of vegetables and medicinal plants all year anywhere, and attain self-sufficiency in food. By providing isolation from the natural environment, a plant factory can achieve higher productivity and safe products. However, the biggest issue with plant factories is the return on investment. Profits are tenuous because of the large initial investments and running costs, i.e. electric power, incurred. At present, LED (Light Emitting Diode) lights are being adopted because they are more energy-efficient and encourage photosynthesis better than the fluorescent lamps used in the past. However, further cost reduction is essential. This paper introduces experiments that reveal which color of LED lighting best enhances the growth of cultured radish sprouts. Radish sprouts were cultivated in the experimental environment formed by a hydroponics kit with three cultivation shelves (28 samples per shelf) each with an artificial lighting rack. Seven LED arrays of different color (white, blue, yellow green, green, yellow, orange, and red) were compared with a fluorescent lamp as the control. Lighting duration was set to 12 hours a day. Normal water with no fertilizer was circulated. Seven days after germination, the length, weight and area of leaf of each sample were measured. Electrical power consumption for all lighting arrangements was also measured. Results and discussions: As to average sample length, no clear difference was observed in terms of color. As regards weight, orange LED was less effective and the difference was significant (p < 0.05). As to leaf area, blue, yellow and orange LEDs were significantly less effective. However, all LEDs offered higher productivity per W consumed than the fluorescent lamp. Of the LEDs, the blue LED array attained the best results in terms of length, weight and area of leaf per W consumed. Conclusion and future works: An experiment on radish sprout cultivation under 7 different color LED arrays showed no clear difference in terms of sample size. However, if electrical power consumption is considered, LEDs offered about twice the growth rate of the fluorescent lamp. Among them, blue LEDs showed the best performance. Further cost reduction e.g. low power lighting remains a big issue for actual system deployment. An automatic plant monitoring system with sensors is another study target.Keywords: electric power consumption, LED color, LED lighting, plant factory
Procedia PDF Downloads 190320 Globalization of Pesticide Technology and Sustainable Agriculture
Authors: Gagandeep Kaur
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The pesticide industry is a big supplier of agricultural inputs. The uses of pesticides control weeds, fungal diseases, etc., which causes of yield losses in agricultural production. In agribusiness and agrichemical industry, Globalization of markets, competition and innovation are the dominant trends. By the tradition of increasing the productivity of agro-systems through generic, universally applicable technologies, innovation in the agrichemical industry is limited. The marketing of technology of agriculture needs to deal with some various trends such as locally-organized forces that envision regionalized sustainable agriculture in the future. Agricultural production has changed dramatically over the past century. Before World War second agricultural production was featured as a low input of money, high labor, mixed farming and low yields. Although mineral fertilizers were applied already in the second half of the 19th century, most f the crops were restricted by local climatic, geological and ecological conditions. After World War second, in the period of reconstruction, political and socioeconomic pressure changed the nature of agricultural production. For a growing population, food security at low prices and securing farmer income at acceptable levels became political priorities. Current agricultural policy the new European common agricultural policy is aimed to reduce overproduction, liberalization of world trade and the protection of landscape and natural habitats. Farmers have to increase the quality of their productivity and they have to control costs because of increased competition from the world market. Pesticides should be more effective at lower application doses, less toxic and not pose a threat to groundwater. There is a big debate taking place about how and whether to mitigate the intensive use of pesticides. This debate is about the future of agriculture which is sustainable agriculture. This is possible by moving away from conventional agriculture. Conventional agriculture is featured as high inputs and high yields. The use of pesticides in conventional agriculture implies crop production in a wide range. To move away from conventional agriculture is possible through the gradual adoption of less disturbing and polluting agricultural practices at the level of the cropping system. For a healthy environment for crop production in the future there is a need for the maintenance of chemical, physical or biological properties. There is also required to minimize the emission of volatile compounds in the atmosphere. Companies are limiting themselves to a particular interpretation of sustainable development, characterized by technological optimism and production-maximizing. So the main objective of the paper will present the trends in the pesticide industry and in agricultural production in the era of Globalization. The second objective is to analyze sustainable agriculture. Companies of pesticides seem to have identified biotechnology as a promising alternative and supplement to the conventional business of selling pesticides. The agricultural sector is in the process of transforming its conventional mode of operation. Some experts give suggestions to farmers to move towards precision farming and some suggest engaging in organic farming. The methodology of the paper will be historical and analytical. Both primary and secondary sources will be used.Keywords: globalization, pesticides, sustainable development, organic farming
Procedia PDF Downloads 99319 A Real-Time Bayesian Decision-Support System for Predicting Suspect Vehicle’s Intended Target Using a Sparse Camera Network
Authors: Payam Mousavi, Andrew L. Stewart, Huiwen You, Aryeh F. G. Fayerman
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We present a decision-support tool to assist an operator in the detection and tracking of a suspect vehicle traveling to an unknown target destination. Multiple data sources, such as traffic cameras, traffic information, weather, etc., are integrated and processed in real-time to infer a suspect’s intended destination chosen from a list of pre-determined high-value targets. Previously, we presented our work in the detection and tracking of vehicles using traffic and airborne cameras. Here, we focus on the fusion and processing of that information to predict a suspect’s behavior. The network of cameras is represented by a directional graph, where the edges correspond to direct road connections between the nodes and the edge weights are proportional to the average time it takes to travel from one node to another. For our experiments, we construct our graph based on the greater Los Angeles subset of the Caltrans’s “Performance Measurement System” (PeMS) dataset. We propose a Bayesian approach where a posterior probability for each target is continuously updated based on detections of the suspect in the live video feeds. Additionally, we introduce the concept of ‘soft interventions’, inspired by the field of Causal Inference. Soft interventions are herein defined as interventions that do not immediately interfere with the suspect’s movements; rather, a soft intervention may induce the suspect into making a new decision, ultimately making their intent more transparent. For example, a soft intervention could be temporarily closing a road a few blocks from the suspect’s current location, which may require the suspect to change their current course. The objective of these interventions is to gain the maximum amount of information about the suspect’s intent in the shortest possible time. Our system currently operates in a human-on-the-loop mode where at each step, a set of recommendations are presented to the operator to aid in decision-making. In principle, the system could operate autonomously, only prompting the operator for critical decisions, allowing the system to significantly scale up to larger areas and multiple suspects. Once the intended target is identified with sufficient confidence, the vehicle is reported to the authorities to take further action. Other recommendations include a selection of road closures, i.e., soft interventions, or to continue monitoring. We evaluate the performance of the proposed system using simulated scenarios where the suspect, starting at random locations, takes a noisy shortest path to their intended target. In all scenarios, the suspect’s intended target is unknown to our system. The decision thresholds are selected to maximize the chances of determining the suspect’s intended target in the minimum amount of time and with the smallest number of interventions. We conclude by discussing the limitations of our current approach to motivate a machine learning approach, based on reinforcement learning in order to relax some of the current limiting assumptions.Keywords: autonomous surveillance, Bayesian reasoning, decision support, interventions, patterns of life, predictive analytics, predictive insights
Procedia PDF Downloads 116318 Exploring Empathy Through Patients’ Eyes: A Thematic Narrative Analysis of Patient Narratives in the UK
Authors: Qudsiya Baig
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Empathy yields an unparalleled therapeutic value within patient physician interactions. Medical research is inundated with evidence to support that a physician’s ability to empathise with patients leads to a greater willingness to report symptoms, an improvement in diagnostic accuracy and safety, and a better adherence and satisfaction with treatment plans. Furthermore, the Institute of Medicine states that empathy leads to a more patient-centred care, which is one of the six main goals of a 21st century health system. However, there is a paradox between the theoretical significance of empathy and its presence, or lack thereof, in clinical practice. Recent studies have reported that empathy declines amongst students and physicians over time. The three most impactful contributors to this decline are: (1) disagreements over the definitions of empathy making it difficult to implement it into practice (2) poor consideration or regulation of empathy leading to burnout and thus, abandonment altogether, and (3) the lack of diversity in the curriculum and the influence of medical culture, which prioritises science over patient experience, limiting some physicians from using ‘too much’ empathy in the fear of losing clinical objectivity. These issues were investigated by conducting a fully inductive thematic narrative analysis of patient narratives in the UK to evaluate the behaviours and attitudes that patients associate with empathy. The principal enquiries underpinning this study included uncovering the factors that affected experience of empathy within provider-patient interactions and to analyse their effects on patient care. This research contributes uniquely to this discourse by examining the phenomenon of empathy directly from patients’ experiences, which were systematically extracted from a repository of online patient narratives of care titled ‘CareOpinion UK’. Narrative analysis was specifically chosen as the methodology to examine narratives from a phenomenological lens to focus on the particularity and context of each story. By enquiring beyond the superficial who-whatwhere, the study of narratives prescribed meaning to illness by highlighting the everyday reality of patients who face the exigent life circumstances created by suffering, disability, and the threat of life. The following six themes were found to be the most impactful in influencing the experience of empathy: dismissive behaviours, judgmental attitudes, undermining patients’ pain or concerns, holistic care and failures and successes of communication or language. For each theme there were overarching themes relating to either a failure to understand the patient’s perspective or a success in taking a person-centred approach. An in-depth analysis revealed that a lack of empathy was greatly associated with an emotive-cognitive imbalance, which disengaged physicians with their patients’ emotions. This study hereby concludes that competent providers require a combination of knowledge, skills, and more importantly empathic attitudes to help create a context for effective care. The crucial elements of that context involve (a) identifying empathy clues within interactions to engage with patients’ situations, (b) attributing a perspective to the patient through perspective-taking and (c) adapting behaviour and communication according to patient’s individual needs. Empathy underpins that context, as does an appreciation of narrative, and the two are interrelated.Keywords: empathy, narratives, person-centred, perspective, perspective-taking
Procedia PDF Downloads 138317 Understanding Beginning Writers' Narrative Writing with a Multidimensional Assessment Approach
Authors: Huijing Wen, Daibao Guo
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Writing is thought to be the most complex facet of language arts. Assessing writing is difficult and subjective, and there are few scientifically validated assessments exist. Research has proposed evaluating writing using a multidimensional approach, including both qualitative and quantitative measures of handwriting, spelling and prose. Given that narrative writing has historically been a staple of literacy instruction in primary grades and is one of the three major genres Common Core State Standards required students to acquire starting in kindergarten, it is essential for teachers to understand how to measure beginning writers writing development and sources of writing difficulties through narrative writing. Guided by the theoretical models of early written expression and using empirical data, this study examines ways teachers can enact a comprehensive approach to understanding beginning writer’s narrative writing through three writing rubrics developed for a Curriculum-based Measurement (CBM). The goal is to help classroom teachers structure a framework for assessing early writing in primary classrooms. Participants in this study included 380 first-grade students from 50 classrooms in 13 schools in three school districts in a Mid-Atlantic state. Three writing tests were used to assess first graders’ writing skills in relation to both transcription (i.e., handwriting fluency and spelling tests) and translational skills (i.e., a narrative prompt). First graders were asked to respond to a narrative prompt in 20 minutes. Grounded in theoretical models of earlier expression and empirical evidence of key contributors to early writing, all written samples to the narrative prompt were coded three ways for different dimensions of writing: length, quality, and genre elements. To measure the quality of the narrative writing, a traditional holistic rating rubric was developed by the researchers based on the CCSS and the general traits of good writing. Students' genre knowledge was measured by using a separate analytic rubric for narrative writing. Findings showed that first-graders had emerging and limited transcriptional and translational skills with a nascent knowledge of genre conventions. The findings of the study provided support for the Not-So-Simple View of Writing in that fluent written expression, measured by length and other important linguistic resources measured by the overall quality and genre knowledge rubrics, are fundamental in early writing development. Our study echoed previous research findings on children's narrative development. The study has practical classroom application as it informs writing instruction and assessment. It offered practical guidelines for classroom instruction by providing teachers with a better understanding of first graders' narrative writing skills and knowledge of genre conventions. Understanding students’ narrative writing provides teachers with more insights into specific strategies students might use during writing and their understanding of good narrative writing. Additionally, it is important for teachers to differentiate writing instruction given the individual differences shown by our multiple writing measures. Overall, the study shed light on beginning writers’ narrative writing, indicating the complexity of early writing development.Keywords: writing assessment, early writing, beginning writers, transcriptional skills, translational skills, primary grades, simple view of writing, writing rubrics, curriculum-based measurement
Procedia PDF Downloads 77316 Strengths Profiling: An Alternative Approach to Assessing Character Strengths Based on Personal Construct Psychology
Authors: Sam J. Cooley, Mary L. Quinton, Benjamin J. Parry, Mark J. G. Holland, Richard J. Whiting, Jennifer Cumming
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Practitioners draw attention to people’s character strengths to promote empowerment and well-being. This paper explores the possibility that existing approaches for assessing character strengths (e.g., the Values in Action survey; VIA-IS) could be even more autonomy supportive and empowering when combined with strengths profiling, an ideographic tool informed by personal construct theory (PCT). A PCT approach ensures that: (1) knowledge is co-created (i.e., the practitioner is not seen as the ‘expert’ who leads the process); (2) individuals are not required to ‘fit’ within a prescribed list of characteristics; and (3) individuals are free to use their own terminology and interpretations. A combined Strengths Profiling and VIA approach was used in a sample of homeless youth (aged 16-25) who are commonly perceived as ‘hard-to-engage’ through traditional forms of assessment. Strengths Profiling was completed face-to-face in small groups. Participants (N = 116) began by listing a variety of personally meaningful characteristics. Participants gave each characteristic a score out of ten for how important it was to them (1 = not so important; 10 = very important), their ideal competency, and their current competency (1 = poor; 10 = excellent). A discrepancy score was calculated for each characteristic (discrepancy score = ideal score - current score x importance), whereby a lower discrepancy score indicated greater satisfaction. Strengths Profiling was used at the beginning and end of a 10-week positive youth development programme. Experiences were captured through video diary room entries made by participants and through reflective notes taken by the facilitators. Participants were also asked to complete a pre-and post-programme questionnaire, measuring perceptions of well-being, self-worth, and resilience. All of the young people who attended the strengths profiling session agreed to complete a profile, and the majority became highly engaged in the process. Strengths profiling was found to be an autonomy supportive and empowering experience, with each participant identifying an average of 10 character strengths (M = 10.27, SD = 3.23). In total, 215 different character strengths were identified, each with varying terms and definitions used, which differed greatly between participants and demonstrated the value in soliciting personal constructs. Using the participants’ definitions, 98% of characteristics were categorized deductively into the VIA framework. Bravery, perseverance, and hope were the character strengths that featured most, whilst temperance and courage received the highest discrepancy scores. Discrepancy scores were negatively correlated with well-being, self-worth, and resilience, and meaningful improvements were recorded following the intervention. These findings support the use of strengths profiling as a theoretically-driven and novel way to engage disadvantaged youth in identifying and monitoring character strengths. When young people are given the freedom to express their own characteristics, the resulting terminologies extend beyond the language used in existing frameworks. This added freedom and control over the process of strengths identification encouraged youth to take ownership over their profiles and apply their strengths. In addition, the ability to transform characteristics post hoc into the VIA framework means that strengths profiling can be used to explore aggregated/nomothetic hypotheses, whilst still benefiting from its ideographic roots.Keywords: ideographic, nomothetic, positive youth development, VIA-IS, assessment, homeless youth
Procedia PDF Downloads 202315 Semi-Supervised Learning for Spanish Speech Recognition Using Deep Neural Networks
Authors: B. R. Campomanes-Alvarez, P. Quiros, B. Fernandez
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Automatic Speech Recognition (ASR) is a machine-based process of decoding and transcribing oral speech. A typical ASR system receives acoustic input from a speaker or an audio file, analyzes it using algorithms, and produces an output in the form of a text. Some speech recognition systems use Hidden Markov Models (HMMs) to deal with the temporal variability of speech and Gaussian Mixture Models (GMMs) to determine how well each state of each HMM fits a short window of frames of coefficients that represents the acoustic input. Another way to evaluate the fit is to use a feed-forward neural network that takes several frames of coefficients as input and produces posterior probabilities over HMM states as output. Deep neural networks (DNNs) that have many hidden layers and are trained using new methods have been shown to outperform GMMs on a variety of speech recognition systems. Acoustic models for state-of-the-art ASR systems are usually training on massive amounts of data. However, audio files with their corresponding transcriptions can be difficult to obtain, especially in the Spanish language. Hence, in the case of these low-resource scenarios, building an ASR model is considered as a complex task due to the lack of labeled data, resulting in an under-trained system. Semi-supervised learning approaches arise as necessary tasks given the high cost of transcribing audio data. The main goal of this proposal is to develop a procedure based on acoustic semi-supervised learning for Spanish ASR systems by using DNNs. This semi-supervised learning approach consists of: (a) Training a seed ASR model with a DNN using a set of audios and their respective transcriptions. A DNN with a one-hidden-layer network was initialized; increasing the number of hidden layers in training, to a five. A refinement, which consisted of the weight matrix plus bias term and a Stochastic Gradient Descent (SGD) training were also performed. The objective function was the cross-entropy criterion. (b) Decoding/testing a set of unlabeled data with the obtained seed model. (c) Selecting a suitable subset of the validated data to retrain the seed model, thereby improving its performance on the target test set. To choose the most precise transcriptions, three confidence scores or metrics, regarding the lattice concept (based on the graph cost, the acoustic cost and a combination of both), was performed as selection technique. The performance of the ASR system will be calculated by means of the Word Error Rate (WER). The test dataset was renewed in order to extract the new transcriptions added to the training dataset. Some experiments were carried out in order to select the best ASR results. A comparison between a GMM-based model without retraining and the DNN proposed system was also made under the same conditions. Results showed that the semi-supervised ASR-model based on DNNs outperformed the GMM-model, in terms of WER, in all tested cases. The best result obtained an improvement of 6% relative WER. Hence, these promising results suggest that the proposed technique could be suitable for building ASR models in low-resource environments.Keywords: automatic speech recognition, deep neural networks, machine learning, semi-supervised learning
Procedia PDF Downloads 341314 Fake News Domination and Threats on Democratic Systems
Authors: Laura Irimies, Cosmin Irimies
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The public space all over the world is currently confronted with the aggressive assault of fake news that have lately impacted public agenda setting, collective decisions and social attitudes. Top leaders constantly call out most mainstream news as “fake news” and the public opinion get more confused. "Fake news" are generally defined as false, often sensational, information disseminated under the guise of news reporting and has been declared the word of the year 2017 by Collins Dictionary and it also has been one of the most debated socio-political topics of recent years. Websites which, deliberately or not, publish misleading information are often shared on social media where they essentially increase their reach and influence. According to international reports, the exposure to fake news is an undeniable reality all over the world as the exposure to completely invented information goes up to the 31 percent in the US, and it is even bigger in Eastern Europe countries, such as Hungary (42%) and Romania (38%) or in Mediterranean countries, such as Greece (44%) or Turkey (49%), and lower in Northern and Western Europe countries – Germany (9%), Denmark (9%) or Holland (10%). While the study of fake news (mechanism and effects) is still in its infancy, it has become truly relevant as the phenomenon seems to have a growing impact on democratic systems. Studies conducted by the European Commission show that 83% of respondents out of a total of 26,576 interviewees consider the existence of news that misrepresent reality as a threat for democracy. Studies recently conducted at Arizona State University show that people with higher education can more easily spot fake headlines, but over 30 percent of them can still be trapped by fake information. If we were to refer only to some of the most recent situations in Romania, fake news issues and hidden agenda suspicions related to the massive and extremely violent public demonstrations held on August 10th, 2018 with a strong participation of the Romanian diaspora have been massively reflected by the international media and generated serious debates within the European Commission. Considering the above framework, the study raises four main research questions: 1. Is fake news a problem or just a natural consequence of mainstream media decline and the abundance of sources of information? 2. What are the implications for democracy? 3. Can fake news be controlled without restricting fundamental human rights? 4. How could the public be properly educated to detect fake news? The research uses mostly qualitative but also quantitative methods, content analysis of studies, websites and media content, official reports and interviews. The study will prove the real threat fake news represent and also the need for proper media literacy education and will draw basic guidelines for developing a new and essential skill: that of detecting fake in news in a society overwhelmed by sources of information that constantly roll massive amounts of information increasing the risk of misinformation and leading to inadequate public decisions that could affect democratic stability.Keywords: agenda setting democracy, fake news, journalism, media literacy
Procedia PDF Downloads 131313 Generative Syntaxes: Macro-Heterophony and the Form of ‘Synchrony’
Authors: Luminiţa Duţică, Gheorghe Duţică
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One of the most powerful language innovation in the twentieth century music was the heterophony–hypostasis of the vertical syntax entered into the sphere of interest of many composers, such as George Enescu, Pierre Boulez, Mauricio Kagel, György Ligeti and others. The heterophonic syntax has a history of its growth, which means a succession of different concepts and writing techniques. The trajectory of settling this phenomenon does not necessarily take into account the chronology: there are highly complex primary stages and advanced stages of returning to the simple forms of writing. In folklore, the plurimelodic simultaneities are free or random and originate from the (unintentional) differences/‘deviations’ from the state of unison, through a variety of ornaments, melismas, imitations, elongations and abbreviations, all in a flexible rhythmic and non-periodic/immeasurable framework, proper to the parlando-rubato rhythmics. Within the general framework of the multivocal organization, the heterophonic syntax in elaborate (academic) version has imposed itself relatively late compared with polyphony and homophony. Of course, the explanation is simple, if we consider the causal relationship between the sound vocabulary elements – in this case, the modalism – and the typologies of vertical organization appropriate for it. Therefore, adding up the ‘classic’ pathway of the writing typologies (monody – polyphony – homophony), heterophony - applied equally to the structures of modal, serial or synthesis vocabulary – reclaims necessarily an own macrotemporal form, in the sense of the analogies enshrined by the evolution of the musical styles and languages: polyphony→fugue, homophony→sonata. Concerned about the prospect of edifying a new musical ontology, the composer Ştefan Niculescu experienced – along with the mathematical organization of heterophony according to his own original methods – the possibility of extrapolation of this phenomenon in macrostructural plan, reaching this way to the unique form of ‘synchrony’. Founded on coincidentia oppositorum principle (involving the ‘one-multiple’ binom), the sound architecture imagined by Ştefan Niculescu consists in one (temporal) model / algorithm of articulation of two sound states: 1. monovocality state (principle of identity) and 2. multivocality state (principle of difference). In this context, the heterophony becomes an (auto)generative mechanism, with macrotemporal amplitude, strategy that will be grown by the composer, practically throughout his creation (see the works: Ison I, Ison II, Unisonos I, Unisonos II, Duplum, Triplum, Psalmus, Héterophonies pour Montreux (Homages to Enescu and Bartók etc.). For the present demonstration, we selected one of the most edifying works of Ştefan Niculescu – Simphony II, Opus dacicum – where the form of (heterophony-)synchrony acquires monumental-symphonic features, representing an emblematic case for the complexity level achieved by this type of vertical syntax in the twentieth century music.Keywords: heterophony, modalism, serialism, synchrony, syntax
Procedia PDF Downloads 345312 Red Dawn in the Desert: A World-Systems Analysis of the Maritime Silk Road Initiative
Authors: Toufic Sarieddine
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The current debate on the hegemonic impact of China’s Belt and Road Initiative (BRI) is of two opposing strands: Resilient and absolute US hegemony on the one hand and various models of multipolar hegemony such as bifurcation on the other. Bifurcation theories illustrate an unprecedented division of hegemonic functions between China and the US, whereby Beijing becomes the world’s economic hegemon, leaving Washington the world’s military hegemon and security guarantor. While consensus points to China being the main driver of unipolarity’s rupturing, the debate among bifurcationists is on the location of the first rupture. In this regard, the Middle East and North Africa (MENA) region has seen increasing Chinese foreign direct investment in recent years while that to other regions has declined, ranking it second in 2018 as part of the financing for the Maritime Silk Road Initiative (MSRI). China has also become the top trade partner of 11 states in the MENA region, as well as its top source of machine imports, surpassing the US and achieving an overall trade surplus almost double that of Washington’s. These are among other features outlined in world-systems analysis (WSA) literature which correspond with the emergence of a new hegemon. WSA is further utilized to gauge other facets of China’s increasing involvement in MENA and assess whether bifurcation is unfolding therein. These features of hegemony include the adoption of China’s modi operandi, economic dominance in production, trade, and finance, military capacity, cultural hegemony in ideology, education, and language, and the promotion of a general interest around which to rally potential peripheries (MENA states in this case). China’s modi operandi has seen some adoption with regards to support against the United Nations Convention on the Law of the Sea, oil bonds denominated in the yuan, and financial institutions such as the Shanghai Gold Exchange enjoying increasing Arab patronage. However, recent elections in Qatar, as well as liberal reforms in Saudi Arabia, demonstrate Washington’s stronger normative influence. Meanwhile, Washington’s economic dominance is challenged by China’s sizable machine exports, increasing overall imports, and widening trade surplus, but retains some clout via dominant arms and transport exports, as well as free-trade deals across the region. Militarily, Washington bests Beijing’s arms exports, has a dominant and well-established presence in the region, and successfully blocked Beijing’s attempt to penetrate through the UAE. Culturally, Beijing enjoys higher favorability in Arab public opinion, and its broadcast networks have found some resonance with Arab audiences. In education, the West remains MENA students’ preferred destination. Further, while Mandarin has become increasingly available in schools across MENA, its usage and availability still lag far behind English. Finally, Beijing’s general interest in infrastructure provision and prioritizing economic development over social justice and democracy provides an avenue for increased incorporation between Beijing and the MENA region. The overall analysis shows solid progress towards bifurcation in MENA.Keywords: belt and road initiative, hegemony, Middle East and North Africa, world-systems analysis
Procedia PDF Downloads 109311 Unleashing the Power of Cerebrospinal System for a Better Computer Architecture
Authors: Lakshmi N. Reddi, Akanksha Varma Sagi
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Studies on biomimetics are largely developed, deriving inspiration from natural processes in our objective world to develop novel technologies. Recent studies are diverse in nature, making their categorization quite challenging. Based on an exhaustive survey, we developed categorizations based on either the essential elements of nature - air, water, land, fire, and space, or on form/shape, functionality, and process. Such diverse studies as aircraft wings inspired by bird wings, a self-cleaning coating inspired by a lotus petal, wetsuits inspired by beaver fur, and search algorithms inspired by arboreal ant path networks lend themselves to these categorizations. Our categorizations of biomimetic studies allowed us to define a different dimension of biomimetics. This new dimension is not restricted to inspiration from the objective world. It is based on the premise that the biological processes observed in the objective world find their reflections in our human bodies in a variety of ways. For example, the lungs provide the most efficient example for liquid-gas phase exchange, the heart exemplifies a very efficient pumping and circulatory system, and the kidneys epitomize the most effective cleaning system. The main focus of this paper is to bring out the magnificence of the cerebro-spinal system (CSS) insofar as it relates to our current computer architecture. In particular, the paper uses four key measures to analyze the differences between CSS and human- engineered computational systems. These are adaptability, sustainability, energy efficiency, and resilience. We found that the cerebrospinal system reveals some important challenges in the development and evolution of our current computer architectures. In particular, the myriad ways in which the CSS is integrated with other systems/processes (circulatory, respiration, etc) offer useful insights on how the human-engineered computational systems could be made more sustainable, energy-efficient, resilient, and adaptable. In our paper, we highlight the energy consumption differences between CSS and our current computational designs. Apart from the obvious differences in materials used between the two, the systemic nature of how CSS functions provides clues to enhance life-cycles of our current computational systems. The rapid formation and changes in the physiology of dendritic spines and their synaptic plasticity causing memory changes (ex., long-term potentiation and long-term depression) allowed us to formulate differences in the adaptability and resilience of CSS. In addition, the CSS is sustained by integrative functions of various organs, and its robustness comes from its interdependence with the circulatory system. The paper documents and analyzes quantifiable differences between the two in terms of the four measures. Our analyses point out the possibilities in the development of computational systems that are more adaptable, sustainable, energy efficient, and resilient. It concludes with the potential approaches for technological advancement through creation of more interconnected and interdependent systems to replicate the effective operation of cerebro-spinal system.Keywords: cerebrospinal system, computer architecture, adaptability, sustainability, resilience, energy efficiency
Procedia PDF Downloads 101310 Influence of the Local External Pressure on Measured Parameters of Cutaneous Microcirculation
Authors: Irina Mizeva, Elena Potapova, Viktor Dremin, Mikhail Mezentsev, Valeri Shupletsov
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The local tissue perfusion is regulated by the microvascular tone which is under the control of a number of physiological mechanisms. Laser Doppler flowmetry (LDF) together with wavelet analyses is the most commonly used technique to study the regulatory mechanisms of cutaneous microcirculation. External factors such as temperature, local pressure of the probe on the skin, etc. influence on the blood flow characteristics and are used as physiological tests to evaluate microvascular regulatory mechanisms. Local probe pressure influences on the microcirculation parameters measured by optical methods: diffuse reflectance spectroscopy, fluorescence spectroscopy, and LDF. Therefore, further study of probe pressure effects can be useful to improve the reliability of optical measurement. During pressure tests variation of the mean perfusion measured by means of LDF usually is estimated. An additional information concerning the physiological mechanisms of the vascular tone regulation system in response to local pressure can be obtained using spectral analyses of LDF samples. The aim of the present work was to develop protocol and algorithm of data processing appropriate for study physiological response to the local pressure test. Involving 6 subjects (20±2 years) and providing 5 measurements for every subject we estimated intersubject and-inter group variability of response of both averaged and oscillating parts of the LDF sample on external surface pressure. The final purpose of the work was to find special features which further can be used in wider clinic studies. The cutaneous perfusion measurements were carried out by LAKK-02 (SPE LAZMA Ltd., Russia), the skin loading was provided by the originally designed device which allows one to distribute the pressure around the LDF probe. The probe was installed on the dorsal part of the distal finger of the index figure. We collected measurements continuously for one hour and varied loading from 0 to 180mmHg stepwise with a step duration of 10 minutes. Further, we post-processed the samples using the wavelet transform and traced the energy of oscillations in five frequency bands over time. Weak loading leads to pressure-induced vasodilation, so one should take into account that the perfusion measured under pressure conditions will be overestimated. On the other hand, we revealed a decrease in endothelial associated fluctuations. Further loading (88 mmHg) induces amplification of pulsations in all frequency bands. We assume that such loading leads to a higher number of closed capillaries, higher input of arterioles in the LDF signal and as a consequence more vivid oscillations which mainly are formed in arterioles. External pressure higher than 144 mmHg leads to the decrease of oscillating components, after removing the loading very rapid restore of the tissue perfusion takes place. In this work, we have demonstrated that local skin loading influence on the microcirculation parameters measured by optic technique; this should be taken into account while developing portable electronic devices. The proposed protocol of local loading allows one to evaluate PIV as far as to trace dynamic of blood flow oscillations. This study was supported by the Russian Science Foundation under project N 18-15-00201.Keywords: blood microcirculation, laser Doppler flowmetry, pressure-induced vasodilation, wavelet analyses blood
Procedia PDF Downloads 151309 Authenticity from the Perspective of Locals: What Prince Edward Islanders Had to Say about Authentic Tourism Experiences
Authors: Susan C. Graham
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Authenticity has grown to be ubiquitous within the tourism vernacular. Yet, agreement regarding what authenticity means in relation to tourism remains nebulous. In its simplest form, authenticity in tourism refers to products and experiences that provide insights into the social, cultural, economic, natural, historical, and political life of a place. But this definition is unwieldy in its scope and may not help industry leaders nor tourist in identifying that which is authentic. Much of what is projected as authentic is a carefully curated and crafted message developed by marketers to appeal to visitors and bears little resemblance to the everyday lives of locals. So perhaps one way to identify authentic tourism experiences is to ask locals themselves. The purpose of this study was to explore the perspectives of locals with respect to what constituted an authentic tourism experience in Prince Edward Island (PEI), Canada. Over 600 volunteers in a tourism research panel were sent a survey asking them to describe authentic PEI experiences within ten sub-categories relevant to the local tourism industry. To make participation more manageable, each respondent was asked their perspectives on any three of the tourism sub-categories. Over 400 individuals responded, providing 1391 unique responses. The responses were grouped thematically using interpretive phenomenological analysis whereby the participants’ responses were clustered into higher order groups to extract meaning. Two interesting thematic observations emerged: first, that respondents tended to clearly articulate and differentiate between intra- versus interpersonal experiences as a means of authentically experiencing PEI; and second, while respondents explicitly valued unstaged experiences over staged, several exceptions to this general rule were expressed. Responses could clearly be grouped into those that emphasized “going off the beaten path,” “exploring pristine and untouched corners,” “lesser known,” “hidden”, “going solo,” and taking the opportunity to “slow down.” Each of these responses was “self” centered, and focused on the visitor discovering and exploring in search of greater self-awareness and inner peace. In contrast, other responses encouraged the interaction of visitors with locals as a means of experiencing the authentic place. Respondents sited “going deep-sea fishing” to learn about local fishers and their communities, stopping by “local farm stands” and speaking with farmers who worked the land for generations,” patronizing “local restaurants, pubs, and b&bs”, and partaking in performances or exhibits by local artists. These kinds of experiences, the respondents claimed, provide an authentic glimpse into a place’s character. The second set of observations focused on the distinction between staged and unstaged experiences, with respondents overwhelmingly advocating for unstaged. Responses were clear in shunning “touristy,” “packaged,” and “fake” offerings for being inauthentic and misrepresenting the place as locals view it. Yet many respondents made exceptions for certain “staged” experiences, including (quite literally) the stage production of Anne of Green Gables based on the novel of the same name, the theatrical re-enactment of the founding of Canada, and visits to PEI’s many provincial and national parks, all of which respondents considered both staged and authentic at the same time.Keywords: authentic, local, Prince Edward Island, tourism
Procedia PDF Downloads 267308 Sustainability Communications Across Multi-Stakeholder Groups: A Critical Review of the Findings from the Hospitality and Tourism Sectors
Authors: Frederica Pettit
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Contribution: Stakeholder involvement in CSR is essential to ensuring pro-environmental attitudes and behaviours across multi-stakeholder groups. Despite increased awareness of the benefits surrounding a collaborative approach to sustainability communications, its success is limited by difficulties engaging with active online conversations with stakeholder groups. Whilst previous research defines the effectiveness of sustainability communications; this paper contributes to knowledge through the development of a theoretical framework that explores the processes to achieving pro-environmental attitudes and behaviours in stakeholder groups. The research will also consider social media as an opportunity to communicate CSR information to all stakeholder groups. Approach: A systematic review was chosen to investigate the effectiveness of the types of sustainability communications used in the hospitality and tourism industries. The systematic review was completed using Web of Science and Scopus using the search terms “sustainab* communicat*” “effective or effectiveness,” and “hospitality or tourism,” limiting the results to peer-reviewed research. 133 abstracts were initially read, with articles being excluded for irrelevance, duplicated articles, non-empirical studies, and language. A total of 45 papers were included as part of the systematic review. 5 propositions were created based on the results of the systematic review, helping to develop a theoretical framework of the processes needed for companies to encourage pro-environmental behaviours across multi-stakeholder groups. Results: The theoretical framework developed in the paper determined the processes necessary for companies to achieve pro-environmental behaviours in stakeholders. The processes to achieving pro-environmental attitudes and behaviours are stakeholder-focused, identifying the need for communications to be specific to their targeted audience. Collaborative communications that enable stakeholders to engage with CSR information and provide feedback lead to a higher awareness of CSR shared visions and pro-environmental attitudes and behaviours. These processes should also aim to improve their relationships with stakeholders through transparency of CSR, CSR strategies that match stakeholder values and ethics whilst prioritizing sustainability as part of their job role. Alternatively, companies can prioritize pro-environmental behaviours using choice editing by mainstreaming sustainability as the only option. In recent years, there has been extensive research on social media as a viable source of sustainability communications, with benefits including direct interactions with stakeholders, the ability to enforce the authenticity of CSR activities and encouragement of pro-environmental behaviours. Despite this, there are challenges to implementing CSR, including difficulties controlling stakeholder criticisms, negative stakeholder influences and comments left on social media platforms. Conclusion: A lack of engagement with CSR information is a reoccurring reason for preventing pro-environmental attitudes and behaviours across stakeholder groups. Traditional CSR strategies contribute to this due to their inability to engage with their intended audience. Hospitality and tourism companies are improving stakeholder relationships through collaborative processes which reduce single-use plastic consumption. A collaborative approach to communications can lead to stakeholder satisfaction, leading to changes in attitudes and behaviours. Different sources of communications are accessed by different stakeholder groups, identifying the need for targeted sustainability messaging, creating benefits such as direct interactions with stakeholders, the ability to enforce the authenticity of CSR activities, and encouraging engagement with sustainability information.Keywords: hospitality, pro-environmental attitudes and behaviours, sustainability communication, social media
Procedia PDF Downloads 139307 Wildfire Risk and Biodiversity Management: Understanding Perceptions and Preparedness
Authors: Emily Moskwa, Delene Weber, Jacob Arnold, Guy M. Robinson, Douglas K. Bardsley
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Management strategies to reduce the risks to human life and property from wildfire are key contemporary concerns, with a growing literature exploring these issues from a social research perspective. Efforts range from narrowly focused examinations, such as comparing the level of community support for vegetation clearance with that of controlled burning, to broader considerations of what constitutes effective fire management policy and education campaigns. However, little analysis is available that integrates the social component of risk mitigation and the influence of educational materials with the biodiversity conservation strategies so often needed in fire-prone ecosystems found on the periphery of urban areas. Indeed many communities living on the fringe of Australian cities face major issues relating to an increased risk of wildfire events and a decline in local biodiversity. Inadequate policy and planning, and a lack of awareness or information, exacerbate this risk. This has brought forward an emerging governance challenge that requires the mitigation of wildfire risk while simultaneously supporting improved conservation practices in these urban-fringe areas. Focusing on the perceptions and experiences of residents of the Lower Eyre Peninsula in South Australia, this study analyses data collected from a series of semi-structured interviews with landholders (n=20) living in rural and urban-fringe areas surrounding the city of Port Lincoln, a city with a growing population and one that has faced a number of very large fires in recent years. In South Australia, new policies have assigned increased responsibility on individual landholders to manage their land and prepare themselves for a wildfire event, potentially to the detriment of the surrounding native vegetation. Our findings indicate the value of gaining a more nuanced understanding of the perceptions and behaviours of landholders living in areas of high fire risk, who often choose to live there in order to be close to the natural environment. Many interviewees demonstrated a high awareness of wildfire risk as a result of their past experience with fire, and the majority considered themselves to be well-prepared in the event of a future fire. Community interactions and educational programs were found to be effective in raising awareness of risk; however, negative trust relationships with government authorities and low exposure to information concerning biodiversity resulted in an overall misunderstanding of the relationship between risk mitigation and biodiversity protection. The study offers insights into how catastrophic fires are reframing perceptions of what constitutes effective vegetation management. It provides recommendations to assist with the development of education strategies that concurrently address wildfire management and biodiversity conservation, and contribute towards environmentally-informed and risk conscious governance.Keywords: biodiversity conservation, risk, peri-urban planning, wildfire management
Procedia PDF Downloads 251306 Efficacy of a Social-Emotional Learning Curriculum for Kindergarten and First Grade Students to Improve Social Adjustment within the School Culture
Authors: Ann P. Daunic, Nancy Corbett
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Background and Significance: Researchers emphasize the role that motivation, self-esteem, and self-regulation play in children’s early adjustment to the school culture, including skills such as identifying their own feelings and understanding the feelings of others. As social-emotional growth, academic learning, and successful integration within culture and society are inextricably connected, the Social-Emotional Learning Foundations (SELF) curriculum was designed to integrate social-emotional learning (SEL) instruction within early literacy instruction (specifically, reading) for Kindergarten and first-grade students at risk for emotional and behavioral difficulties. Storybook reading is a typically occurring activity in the primary grades; thus SELF provides an intervention that is both theoretically and practically sound. Methodology: The researchers will report on findings from the first two years of a three-year study funded by the US Department of Education’s Institute of Education Sciences to evaluate the effects of the SELF curriculum versus “business as usual” (BAU). SELF promotes the development of self-regulation by incorporating instructional strategies that support children’s use of SEL related vocabulary, self-talk, and critical thinking. The curriculum consists of a carefully coordinated set of materials and pedagogy designed specifically for primary grade children at early risk for emotional and behavioral difficulties. SELF lessons (approximately 50 at each grade level) are organized around 17 SEL topics within five critical competencies. SELF combines whole-group (the first in each topic) and small-group lessons (the 2nd and 3rd in each topic) to maximize opportunities for teacher modeling and language interactions. The researchers hypothesize that SELF offers a feasible and substantial opportunity within the classroom setting to provide a small-group social-emotional learning intervention integrated with K-1 literacy-related instruction. Participating target students (N = 876) were identified by their teachers as potentially at risk for emotional or behavioral issues. These students were selected from 122 Kindergarten and 100 first grade classrooms across diverse school districts in a southern state in the US. To measure the effectiveness of the SELF intervention, the researchers asked teachers to complete assessments related to social-emotional learning and adjustment to the school culture. A social-emotional learning related vocabulary assessment was administered directly to target students receiving small-group instruction. Data were analyzed using a 3-level MANOVA model with full information maximum likelihood to estimate coefficients and test hypotheses. Major Findings: SELF had significant positive effects on vocabulary, knowledge, and skills associated with social-emotional competencies, as evidenced by results from the measures administered. Effect sizes ranged from 0.41 for group (SELF vs. BAU) differences in vocabulary development to 0.68 for group differences in SEL related knowledge. Conclusion: Findings from two years of data collection indicate that SELF improved outcomes related to social-emotional learning and adjustment to the school culture. This study thus supports the integration of SEL with literacy instruction as a feasible and effective strategy to improve outcomes for K-1 students at risk for emotional and behavioral difficulties.Keywords: Socio-cultural context for learning, social-emotional learning, social skills, vocabulary development
Procedia PDF Downloads 128305 Optimization of the Performance of a Solar Concentrator System with a Cavity Receiver Using the Genetic Algorithm
Authors: Foozhan Gharehkhani
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The use of solar energy as a sustainable renewable energy source has gained significant attention in recent years. Solar concentrating systems (CSP), which direct solar radiation onto a receiver, are an effective means of producing high-temperature thermal energy. Cavity receivers, known for their high thermal efficiency and reduced heat losses, are particularly noteworthy in these systems. Optimizing their design can enhance energy efficiency and reduce costs. This study leverages the genetic algorithm, a powerful optimization tool inspired by natural evolution, to optimize the performance of a solar concentrator system with a cavity receiver, aiming for a more efficient and cost-effective design. In this study, a system consisting of a solar concentrator and a cavity receiver was analyzed. The concentrator was designed as a parabolic dish, and the receiver had a cylindrical cavity with a helical structure. The primary parameters were defined as the cavity diameter (D), the receiver height (h), and the helical pipe diameter (d). Initially, the system was optimized to achieve the maximum heat flux, and the optimal parameter values along with the maximum heat flux were obtained. Subsequently, a multi-objective optimization approach was applied, aiming to maximize the heat flux while minimizing the system construction cost. The optimization process was conducted using the genetic algorithm implemented in MATLAB with precise execution. The results of this study revealed that the optimal dimensions of the receiver, including the cavity diameter (D), receiver height (h), and helical pipe diameter (d), were determined to be 0.142 m, 0.1385 m, and 0.011 m, respectively. This optimization resulted in improvements of 3% in the cavity diameter, 8% in the height, and 5% in the helical pipe diameter. Furthermore, the results indicated that the primary focus of this research was the accurate thermal modeling of the solar collection system. The simulations and the obtained results demonstrated that the optimization applied to this system maximized its thermal performance and elevated its energy efficiency to a desirable level. Moreover, this study successfully modeled and controlled effective temperature variations at different angles of solar irradiation, highlighting significant improvements in system efficiency. The significance of this research lies in leveraging solar energy as one of the prominent renewable energy sources, playing a key role in replacing fossil fuels. Considering the environmental and economic challenges associated with the excessive use of fossil resources—such as increased greenhouse gas emissions, environmental degradation, and the depletion of fossil energy reserves—developing technologies related to renewable energy has become a vital priority. Among these, solar concentrating systems, capable of achieving high temperatures, are particularly important for industrial and heating applications. This research aims to optimize the performance of such systems through precise design and simulation, making a significant contribution to the advancement of advanced technologies and the efficient utilization of solar energy in Iran, thereby addressing the country's future energy needs effectively.Keywords: cavity receiver, genetic algorithm, optimization, solar concentrator system performance
Procedia PDF Downloads 10304 C-Coordinated Chitosan Metal Complexes: Design, Synthesis and Antifungal Properties
Authors: Weixiang Liu, Yukun Qin, Song Liu, Pengcheng Li
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Plant diseases can cause the death of crops with great economic losses. Particularly, those diseases are usually caused by pathogenic fungi. Metal fungicides are a type of pesticide that has advantages of a low-cost, broad antimicrobial spectrum and strong sterilization effect. However, the frequent and wide application of traditional metal fungicides has caused serious problems such as environmental pollution, the outbreak of mites and phytotoxicity. Therefore, it is critically necessary to discover new organic metal fungicides alternatives that have a low metal content, low toxicity, and little influence on mites. Chitosan, the second most abundant natural polysaccharide next to cellulose, was proved to have broad-spectrum antifungal activity against a variety of fungi. However, the use of chitosan was limited due to its poor solubility and weaker antifungal activity compared with commercial fungicide. Therefore, in order to improve the water solubility and antifungal activity, many researchers grafted the active groups onto chitosan. The present work was to combine free metal ions with chitosan, to prepare more potent antifungal chitosan derivatives, thus, based on condensation reaction, chitosan derivative bearing amino pyridine group was prepared and subsequently followed by coordination with cupric ions, zinc ions and nickel ions to synthesize chitosan metal complexes. The calculations by density functional theory (DFT) show that the copper ions and nickel ions underwent dsp2 hybridization, the zinc ions underwent sp3 hybridization, and all of them are coordinated by the carbon atom in the p-π conjugate group and the oxygen atoms in the acetate ion. The antifungal properties of chitosan metal complexes against Phytophthora capsici (P. capsici), Gibberella zeae (G. zeae), Fusarium oxysporum (F. oxysporum) and Botrytis cinerea (B. cinerea) were also assayed. In addition, a plant toxicity experiment was carried out. The experiments indicated that the derivatives have significantly enhanced antifungal activity after metal ions complexation compared with the original chitosan. It was shown that 0.20 mg/mL of O-CSPX-Cu can 100% inhibit the growth of P. capsici and 0.20 mg/mL of O-CSPX-Ni can 87.5% inhibit the growth of B. cinerea. In general, their activities are better than the positive control oligosaccharides. The combination of the pyridine formyl groups seems to favor biological activity. Additionally, the ligand fashion was precisely analyzed, and the results revealed that the copper ions and nickel ions underwent dsp2 hybridization, the zinc ions underwent sp3 hybridization, and the carbon atoms of the p-π conjugate group and the oxygen atoms of acetate ion are involved in the coordination of metal ions. The phytotoxicity assay of O-CSPX-M was also conducted, unlike the traditional metal fungicides, the metal complexes were not significantly toxic to the leaves of wheat. O-CSPX-Zn can even increase chlorophyll content in wheat leaves at 0.40 mg/mL. This is mainly because chitosan itself promotes plant growth and counteracts the phytotoxicity of metal ions. The chitosan derivative described here may lend themselves to future applicative studies in crop protection.Keywords: coordination, chitosan, metal complex, antifungal properties
Procedia PDF Downloads 319303 A Computer-Aided System for Tooth Shade Matching
Authors: Zuhal Kurt, Meral Kurt, Bilge T. Bal, Kemal Ozkan
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Shade matching and reproduction is the most important element of success in prosthetic dentistry. Until recently, shade matching procedure was implemented by dentists visual perception with the help of shade guides. Since many factors influence visual perception; tooth shade matching using visual devices (shade guides) is highly subjective and inconsistent. Subjective nature of this process has lead to the development of instrumental devices. Nowadays, colorimeters, spectrophotometers, spectroradiometers and digital image analysing systems are used for instrumental shade selection. Instrumental devices have advantages that readings are quantifiable, can obtain more rapidly and simply, objectively and precisely. However, these devices have noticeable drawbacks. For example, translucent structure and irregular surfaces of teeth lead to defects on measurement with these devices. Also between the results acquired by devices with different measurement principles may make inconsistencies. So, its obligatory to search for new methods for dental shade matching process. A computer-aided system device; digital camera has developed rapidly upon today. Currently, advances in image processing and computing have resulted in the extensive use of digital cameras for color imaging. This procedure has a much cheaper process than the use of traditional contact-type color measurement devices. Digital cameras can be taken by the place of contact-type instruments for shade selection and overcome their disadvantages. Images taken from teeth show morphology and color texture of teeth. In last decades, a new method was recommended to compare the color of shade tabs taken by a digital camera using color features. This method showed that visual and computer-aided shade matching systems should be used as concatenated. Recently using methods of feature extraction techniques are based on shape description and not used color information. However, color is mostly experienced as an essential property in depicting and extracting features from objects in the world around us. When local feature descriptors with color information are extended by concatenating color descriptor with the shape descriptor, that descriptor will be effective on visual object recognition and classification task. Therefore, the color descriptor is to be used in combination with a shape descriptor it does not need to contain any spatial information, which leads us to use local histograms. This local color histogram method is remain reliable under variation of photometric changes, geometrical changes and variation of image quality. So, coloring local feature extraction methods are used to extract features, and also the Scale Invariant Feature Transform (SIFT) descriptor used to for shape description in the proposed method. After the combination of these descriptors, the state-of-art descriptor named by Color-SIFT will be used in this study. Finally, the image feature vectors obtained from quantization algorithm are fed to classifiers such as Nearest Neighbor (KNN), Naive Bayes or Support Vector Machines (SVM) to determine label(s) of the visual object category or matching. In this study, SVM are used as classifiers for color determination and shade matching. Finally, experimental results of this method will be compared with other recent studies. It is concluded from the study that the proposed method is remarkable development on computer aided tooth shade determination system.Keywords: classifiers, color determination, computer-aided system, tooth shade matching, feature extraction
Procedia PDF Downloads 448302 Oxidative Dehydrogenation and Hydrogenation of Malic Acid over Transition Metal Oxides
Authors: Gheorghiţa Mitran, Adriana Urdă, Mihaela Florea, Octavian Dumitru Pavel, Florentina Neaţu
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Oxidative dehydrogenation and hydrogenation reactions of L-malic acid are interesting ways for its transformation into valuable products, including oxaloacetic, pyruvic and malonic acids but also 1,4-butanediol and 1,2,4-butanetriol. Keto acids have a range of applicationsin many chemical syntheses as pharmaceuticals, food additives and cosmetics. 3-Hydroxybutyrolactone and 1,2,4-butanetriol are used for the synthesis of chiral pharmaceuticals and other fine chemicals, while 1,4-butanediol can be used for organic syntheses, such as polybutylene succinate (PBS), polybutylene terephthalate (PBT), and for production of tetrahydrofuran (THF). L-malic acid is a non-toxic and natural organic acid present in fruits, and it is the main component of wine alongside tartaric acid representing about 90% of the wine total acidity. Iron oxides dopped with cobalt (CoxFe3-xO4; x= 0; 0.05; 0.1; 0.15) were studied as catalysts in these reactions. There is no mention in the literature of non-noble transition metal catalysts for these reactions. The method used for catalysts preparation was coprecipitation, whileBET XRD, XPS, FTIR and UV-VIS spectroscopy were used for the physicochemical properties evaluation.TheXRD patterns revealed the presence of α-Fe2O3 rhombohedral hematite structure, with cobalt atoms well dispersed and embedded in this structure. The studied samples are highly crystalline, with a crystallite size ranged from 58 to 65 nm. The optical absorption properties were investigated using UV-Vis spectroscopy, emphasizing the presence of bands that correspond with the reported hematite nanoparticle. Likewise, the presence of bands corresponding to lattice vibration of hexagonal hematite structurehas been evidenced in DRIFT spectra. Oxidative dehydrogenation of malic acid was studied using as solvents for malic acid ethanol or water(2, 5 and 10% malic acid in 5 mL solvent)at room temperature, while the hydrogenation reaction was evaluated in water as solvent (5%), in the presence of 1% catalyst. The oxidation of malic acid into oxaloacetic acid is the first step, after that, oxaloacetic acid is rapidly decarboxylated to malonic acid or pyruvic acid, depending on the active site. The concentration of malic acid in solution, it, in turn, has an influence on conversionthis decreases when the concentration of malic acid in the solution is high. The spent catalysts after the oxidative dehydrogenation of malic acid in ethanol were characterized by DRIFT spectroscopy and the presence of oxaloacetic, pyruvic and malonicacids, along with unreacted malic acidwere observed on the surface. The increase of the ratio of Co/Fe on the surface has an influence on the malic acid conversion and on the pyruvic acid yield, while the yield of malonic acid is influenced by the percentage of iron on the surface (determined from XPS). Oxaloacetic acid yield reaches a maximumat one hour of reaction, being higher when ethanol is used as a solvent, after which it suddenly decreases. The hydrogenation of malic acid occurs by consecutive reactions with the production of 3-hydroxy-butyrolactone, 1,2,4-butanetriol and 1,4-butanediol. Malic acid conversion increases with cobalt loading increasing up to Co/Fe ratio of 0.1, after which it has a slight decrease, while the yield in 1,4-butanediol is directly proportional to the cobalt content.Keywords: malic acid, oxidative dehydrogenation, hydrogenation, oxaloacetic acid
Procedia PDF Downloads 184301 Exploring Bio-Inspired Catecholamine Chemistry to Design Durable Anti-Fungal Wound Dressings
Authors: Chetna Dhand, Venkatesh Mayandi, Silvia Marrero Diaz, Roger W. Beuerman, Seeram Ramakrishna, Rajamani Lakshminarayanan
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Sturdy Insect Cuticle Sclerotization, Incredible Substrate independent Mussel’s bioadhesion, Tanning of Leather are some of catechol(amine)s mediated natural processes. Chemical contemplation spots toward a mechanism instigated with the formation of the quinone moieties from the respective catechol(amine)s, via oxidation, followed by the nucleophilic addition of the amino acids/proteins/peptides to this quinone leads to the development of highly strong, cross-linked and water-resistant proteinacious structures. Inspired with this remarkable catechol(amine)s chemistry towards amino acids/proteins/peptides, we attempted to design highly stable and water-resistant antifungal wound dressing mats with exceptional durability using collagen (protein), dopamine (catecholamine) and antifungal drugs (Amphotericin B and Caspofungin) as the key materials. Electrospinning technique has been used to fabricate desired nanofibrous mat including Collagen (COLL), COLL/Dopamine (COLL/DP) and calcium incorporated COLL/DP (COLL-DP-Ca2+). The prepared protein-based scaffolds have been studied for their microscopic investigations (SEM, TEM, and AFM), structural analysis (FT-IR), mechanical properties, water wettability characteristics and aqueous stability. Biocompatibility of these scaffolds has been analyzed for dermal fibroblast cells using MTS assay, Cell TrackerTM Green CMFDA and confocal imaging. Being the winner sample, COLL-DP-Ca2+ scaffold has been selected for incorporating two antifungal drugs namely Caspofungin (Peptide based) and Amphotericin B (Non-Peptide based). Antifungal efficiency of the designed mats has been evaluated for eight diverse fungal strains employing different microbial assays including disc diffusion, cell-viability assay, time kill kinetics etc. To confirm the durability of these mats, in term of their antifungal activity, drug leaching studies has been performed and monitored using disc diffusion assay each day. Ex-vivo fungal infection model has also been developed and utilized to validate the antifungal efficacy of the designed wound dressings. Results clearly reveal dopamine mediated crosslinking within COLL-antifungal scaffolds that leads to the generation of highly stable, mechanical tough, biocompatible wound dressings having the zone of inhabitation of ≥ 2 cm for almost all the investigated fungal strains. Leaching studies and Ex-vivo model has confirmed the durability of these wound dressing for more than 3 weeks and certified their suitability for commercialization. A model has also been proposed to enlighten the chemical mechanism involved for the development of these antifungal wound dressings with exceptional robustness.Keywords: catecholamine chemistry, electrospinning technique, antifungals, wound dressings, collagen
Procedia PDF Downloads 378300 Improved Anatomy Teaching by the 3D Slicer Platform
Authors: Ahmedou Moulaye Idriss, Yahya Tfeil
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Medical imaging technology has become an indispensable tool in many branches of the biomedical, health area, and research and is vitally important for the training of professionals in these fields. It is not only about the tools, technologies, and knowledge provided but also about the community that this training project proposes. In order to be able to raise the level of anatomy teaching in the medical school of Nouakchott in Mauritania, it is necessary and even urgent to facilitate access to modern technology for African countries. The role of technology as a key driver of justifiable development has long been recognized. Anatomy is an essential discipline for the training of medical students; it is a key element for the training of medical specialists. The quality and results of the work of a young surgeon depend on his better knowledge of anatomical structures. The teaching of anatomy is difficult as the discipline is being neglected by medical students in many academic institutions. However, anatomy remains a vital part of any medical education program. When anatomy is presented in various planes medical students approve of difficulties in understanding. They do not increase their ability to visualize and mentally manipulate 3D structures. They are sometimes not able to correctly identify neighbouring or associated structures. This is the case when they have to make the identification of structures related to the caudate lobe when the liver is moved to different positions. In recent decades, some modern educational tools using digital sources tend to replace old methods. One of the main reasons for this change is the lack of cadavers in laboratories with poorly qualified staff. The emergence of increasingly sophisticated mathematical models, image processing, and visualization tools in biomedical imaging research have enabled sophisticated three-dimensional (3D) representations of anatomical structures. In this paper, we report our current experience in the Faculty of Medicine in Nouakchott Mauritania. One of our main aims is to create a local learning community in the fields of anatomy. The main technological platform used in this project is called 3D Slicer. 3D Slicer platform is an open-source application available for free for viewing, analysis, and interaction with biomedical imaging data. Using the 3D Slicer platform, we created from real medical images anatomical atlases of parts of the human body, including head, thorax, abdomen, liver, and pelvis, upper and lower limbs. Data were collected from several local hospitals and also from the website. We used MRI and CT-Scan imaging data from children and adults. Many different anatomy atlases exist, both in print and digital forms. Anatomy Atlas displays three-dimensional anatomical models, image cross-sections of labelled structures and source radiological imaging, and a text-based hierarchy of structures. Open and free online anatomical atlases developed by our anatomy laboratory team will be available to our students. This will allow pedagogical autonomy and remedy the shortcomings by responding more fully to the objectives of sustainable local development of quality education and good health at the national level. To make this work a reality, our team produced several atlases available in our faculty in the form of research projects.Keywords: anatomy, education, medical imaging, three dimensional
Procedia PDF Downloads 244299 Ethnobotanical Study of Traditional Medicinal Plants Used by Indigenous Tribal People of Kodagu District, Central Western Ghats, Karnataka, India
Authors: Anush Patric, M. Jadeyegowda, M. N. Ramesh, M. Ravikumar, C. R. Ajay
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Kodagu district which is situated in Central Western Ghats regions falls in one of the hottest of hot spots of biodiversity which is recognised by UNESCO. The district has one of the highest densities of community managed sacred forests in the world with rich floral and faunal diversity. It is a habitat for more than ten different types of Ethnic Indigenous tribal groups commonly called ‘Girijanas’ (Soligas, Yarvas, Jenukuruba, Bettakuruba etc.), who are having the rich knowledge of medicinal value of the plants that are commonly available in the forest. The tribal men of this region are the treasure house of the traditional plant knowledge and health care practices. An ethnobotanical survey was undertaken in tribal areas of the district to collect information about some of the indigenous medicinal plant knowledge of tribal people by semi-structured interviews, ranking exercises and field observations on their native habitat in order to evaluate the potential medicinal uses of local plants. The study revealed that, the ethnobotanical information of 83 plant species belonging to 45 families, of the total 83 species documented, most plants used in the treatment were trees (11 species), shrubs (41 species), herbs (22 species) and rarely climbers (9 species) which are used in the treatment of Hyperacidity, Respiratory disorders, Snake bite Abortifacient, Anthelmintic, Paralysis, Antiseptic, Fever, Chest pain, Stomachic, Jaundice, Piles, Asthma, Malaria, Renal disorders, Malaria and many other diseases. Maximum of 6 plant species each of Acanthaceae, Apiaceae and were used for drug preparation, followed by Asclepiadaceae, Liliaceae, Fabaceae, Verbenaceae, Caesalpinaceae, Bombaceae, Papilonaceae, Solanaceae, Rubiaceae, Myrtaceae, Amaranthaceae, Asteraceae, Ascelepidaceae, Cucurbitaceae, Apocyanaceae, and Solanaceae etc. In our present study, only medicinal plants and their local medicinal uses are recorded and presented. Information was obtained by local informants having the knowledge about medicinal plants. About 23 local tribes were interviewed. For each plant, necessary information like botanical name, family of plant species, local name and uses are given. Recent trend shows a decline in the number of traditional herbal healers in the tribal areas since the younger generation is not interested to continue this tradition. Hence, there is an urgent need to record and preserve all information on plants used by different ethnic/tribal communities for various purposes before it reaches to verge of extinction. In addition, several wild medicinal plants are declining in numbers due to deforestation and forest fires. There is need for phytochemical analysis and conservation measures to be taken for conserving medicinal plant species which is far better than allopathic medicines and these do not cause any side effects as they are the natural disease healers. So, conservation strategies have to be practiced in all levels and sectors by creating awareness about the value of such medicinal plants, and it is necessary to save the disappearing plants to strengthen the document and to conserve them for future generation.Keywords: diseases, ethnic groups, folk medicine, Kodagu, medicinal plants
Procedia PDF Downloads 263298 Vortex Generation to Model the Airflow Downstream of a Piezoelectric Fan Array
Authors: Alastair Hales, Xi Jiang, Siming Zhang
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Numerical methods are used to generate vortices in a domain. Through considered design, two counter-rotating vortices may interact and effectively drive one another downstream. This phenomenon is comparable to the vortex interaction that occurs in a region immediately downstream from two counter-oscillating piezoelectric (PE) fan blades. PE fans are small blades clamped at one end and driven to oscillate at their first natural frequency by an extremely low powered actuator. In operation, the high oscillation amplitude and frequency generate sufficient blade tip speed through the surrounding air to create downstream air flow. PE fans are considered an ideal solution for low power hot spot cooling in a range of small electronic devices, but a single blade does not typically induce enough air flow to be considered a direct alternative to conventional air movers, such as axial fans. The development of face-to-face PE fan arrays containing multiple blades oscillating in counter-phase to one another is essential for expanding the range of potential PE fan applications regarding the cooling of power electronics. Even in an unoptimised state, these arrays are capable of moving air volumes comparable to axial fans with less than 50% of the power demand. Replicating the airflow generated by face-to-face PE fan arrays without including the actual blades in the model reduces the process’s computational demands and enhances the rate of innovation and development in the field. Vortices are generated at a defined inlet using a time-dependent velocity profile function, which pulsates the inlet air velocity magnitude. This induces vortex generation in the considered domain, and these vortices are shown to separate and propagate downstream in a regular manner. The generation and propagation of a single vortex are compared to an equivalent vortex generated from a PE fan blade in a previous experimental investigation. Vortex separation is found to be accurately replicated in the present numerical model. Additionally, the downstream trajectory of the vortices’ centres vary by just 10.5%, and size and strength of the vortices differ by a maximum of 10.6%. Through non-dimensionalisation, the numerical method is shown to be valid for PE fan blades with differing parameters to the specific case investigated. The thorough validation methods presented verify that the numerical model may be used to replicate vortex formation from an oscillating PE fans blade. An investigation is carried out to evaluate the effects of varying the distance between two PE fan blade, pitch. At small pitch, the vorticity in the domain is maximised, along with turbulence in the near vicinity of the inlet zones. It is proposed that face-to-face PE fan arrays, oscillating in counter-phase, should have a minimal pitch to optimally cool nearby heat sources. On the other hand, downstream airflow is maximised at a larger pitch, where the vortices can fully form and effectively drive one another downstream. As such, this should be implemented when bulk airflow generation is the desired result.Keywords: piezoelectric fans, low energy cooling, vortex formation, computational fluid dynamics
Procedia PDF Downloads 185297 Synergistic Studies of Liposomes of Clove and Cinnamon Oil in Oral Health Care
Authors: Sandhya Parameswaran, Prajakta Dhuri
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Despite great improvements in health care, the world oral health report states that dental problems still persist, particularly among underprivileged groups in both developing and developed countries. Dental caries and periodontal diseases are identified as the most important oral health problems globally. Acidic foods and beverages can affect natural teeth, and chronic exposure often leads to the development of dental erosion, abrasion, and decay. In recent years, there has been an increased interest toward essential oils. These are secondary metabolites and possess antibacterial, antifungal and antioxidant properties. Essential oils are volatile and chemically unstable in the presence of air, light, moisture and high temperature. Hence many novel methods like a liposomal encapsulation of oils have been introduced to enhance the stability and bioavailability. This research paper focuses on two essential oils, clove and cinnamon oil. Clove oil was obtained from Syzygium aromaticum Linn using clavengers apparatus. It contains eugenol and β caryophyllene. Cinnamon oil, from the barks of Cinnamomum cassia, contains cinnamaldehyde, The objective of the current research was to develop a liposomal carrier system containing clove and cinnamon oil and study their synergistic activity against dental pathogens when formulated as a gel. Methodology: The essential oil were first tested for their antimicrobial activity against dental pathogens, Lactobacillus acidophillus (MTCC No. 10307, MRS broth) and Streptococcus Mutans (MTCC No .890, Brain Heart Infusion agar). The oils were analysed by UV spectroscopy for eugenol and cinnamaldehyde content. Standard eugenol was linear between 5ppm to 25ppm at 282nm and standard cinnamaldehde from 1ppm to 5pmm at 284nm. The concentration of eugenol in clove oil was found to be 62.65 % w/w, and that of cinnamaldehyde was found to be 5.15%s w/w. The oils were then formulated into liposomes. Liposomes were prepared by thin film hydration method using Phospholipid, Cholesterol, and other oils dissolved in a chloroform methanol (3:1) mixture. The organic solvent was evaporated in a rotary evaporator above lipid transition temperature. The film was hydrated with phosphate buffer (pH 5.5).The various batches of liposomes were characterized and compared for their size, loading rate, encapsulation efficiency and morphology. The prepared liposomes when evaluated for entrapment efficiency showed 65% entrapment for clove and 85% for cinnamon oil. They were also tested for their antimicrobial activity against dental pathogens and their synergistic activity studied. Based on the activity and the entrapment efficiency the amount of liposomes required to prepare 1gm of the gel was calculated. The gel was prepared using a simple ointment base and contained 0.56% of cinnamon and clove liposomes. A simultaneous method of analysis for eugenol and cinnamaldehyde.was then developed using HPLC. The prepared gels were then studied for their stability as per ICH guidelines. Conclusion: It was found that liposomes exhibited spherical shaped vesicles and protected the essential oil from degradation. Liposomes, therefore, constitute a suitable system for encapsulation of volatile, unstable essential oil constituents.Keywords: cinnamon oil, clove oil, dental caries, liposomes
Procedia PDF Downloads 195296 Biomaterials Solutions to Medical Problems: A Technical Review
Authors: Ashish Thakur
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This technical paper was written in view of focusing the biomaterials and its various applications in modern industries. Author tires to elaborate not only the medical, infect plenty of application in other industries. The scope of the research area covers the wide range of physical, biological and chemical sciences that underpin the design of biomaterials and the clinical disciplines in which they are used. A biomaterial is now defined as a substance that has been engineered to take a form which, alone or as part of a complex system, is used to direct, by control of interactions with components of living systems, the course of any therapeutic or diagnostic procedure. Biomaterials are invariably in contact with living tissues. Thus, interactions between the surface of a synthetic material and biological environment must be well understood. This paper reviews the benefits and challenges associated with surface modification of the metals in biomedical applications. The paper also elaborates how the surface characteristics of metallic biomaterials, such as surface chemistry, topography, surface charge, and wettability, influence the protein adsorption and subsequent cell behavior in terms of adhesion, proliferation, and differentiation at the biomaterial–tissue interface. The chapter also highlights various techniques required for surface modification and coating of metallic biomaterials, including physicochemical and biochemical surface treatments and calcium phosphate and oxide coatings. In this review, the attention is focused on the biomaterial-associated infections, from which the need for anti-infective biomaterials originates. Biomaterial-associated infections differ markedly for epidemiology, aetiology and severity, depending mainly on the anatomic site, on the time of biomaterial application, and on the depth of the tissues harbouring the prosthesis. Here, the diversity and complexity of the different scenarios where medical devices are currently utilised are explored, providing an overview of the emblematic applicative fields and of the requirements for anti-infective biomaterials. In addition to this, chapter introduces nanomedicine and the use of both natural and synthetic polymeric biomaterials, focuses on specific current polymeric nanomedicine applications and research, and concludes with the challenges of nanomedicine research. Infection is currently regarded as the most severe and devastating complication associated to the use of biomaterials. Osteoporosis is a worldwide disease with a very high prevalence in humans older than 50. The main clinical consequences are bone fractures, which often lead to patient disability or even death. A number of commercial biomaterials are currently used to treat osteoporotic bone fractures, but most of these have not been specifically designed for that purpose. Many drug- or cell-loaded biomaterials have been proposed in research laboratories, but very few have received approval for commercial use. Polymeric nanomaterial-based therapeutics plays a key role in the field of medicine in treatment areas such as drug delivery, tissue engineering, cancer, diabetes, and neurodegenerative diseases. Advantages in the use of polymers over other materials for nanomedicine include increased functionality, design flexibility, improved processability, and, in some cases, biocompatibility.Keywords: nanomedicine, tissue, infections, biomaterials
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