Search results for: water potential
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 18024

Search results for: water potential

4884 Development of Nondestructive Imaging Analysis Method Using Muonic X-Ray with a Double-Sided Silicon Strip Detector

Authors: I-Huan Chiu, Kazuhiko Ninomiya, Shin’ichiro Takeda, Meito Kajino, Miho Katsuragawa, Shunsaku Nagasawa, Atsushi Shinohara, Tadayuki Takahashi, Ryota Tomaru, Shin Watanabe, Goro Yabu

Abstract:

In recent years, a nondestructive elemental analysis method based on muonic X-ray measurements has been developed and applied for various samples. Muonic X-rays are emitted after the formation of a muonic atom, which occurs when a negatively charged muon is captured in a muon atomic orbit around the nucleus. Because muonic X-rays have higher energy than electronic X-rays due to the muon mass, they can be measured without being absorbed by a material. Thus, estimating the two-dimensional (2D) elemental distribution of a sample became possible using an X-ray imaging detector. In this work, we report a non-destructive imaging experiment using muonic X-rays at Japan Proton Accelerator Research Complex. The irradiated target consisted of polypropylene material, and a double-sided silicon strip detector, which was developed as an imaging detector for astronomical observation, was employed. A peak corresponding to muonic X-rays from the carbon atoms in the target was clearly observed in the energy spectrum at an energy of 14 keV, and 2D visualizations were successfully reconstructed to reveal the projection image from the target. This result demonstrates the potential of the non-destructive elemental imaging method that is based on muonic X-ray measurement. To obtain a higher position resolution for imaging a smaller target, a new detector system will be developed to improve the statistical analysis in further research.

Keywords: DSSD, muon, muonic X-ray, imaging, non-destructive analysis

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4883 Building Information Modelling (BIM) and Unmanned Aerial Vehicles (UAV) Technologies in Road Construction Project Monitoring and Management: Case Study of a Project in Cyprus

Authors: Yiannis Vacanas, Kyriacos Themistocleous, Athos Agapiou, Diofantos Hadjimitsis

Abstract:

Building Information Modelling (BIM) technology is considered by construction professionals as a very valuable process in modern design, procurement and project management. Construction professionals of all disciplines can use a single 3D model which BIM technology provides, to design a project accurately and furthermore monitor the progress of construction works effectively and efficiently. Unmanned Aerial Vehicles (UAVs), a technology initially developed for military applications, is now without any difficulty accessible and has already been used by commercial industries, including the construction industry. UAV technology has mainly been used for collection of images that allow visual monitoring of building and civil engineering projects conditions in various circumstances. UAVs, nevertheless, have undergone significant advances in equipment capabilities and now have the capacity to acquire high-resolution imagery from many angles in a cost effective manner, and by using photogrammetry methods, someone can determine characteristics such as distances, angles, areas, volumes and elevations of an area within overlapping images. In order to examine the potential of using a combination of BIM and UAV technologies in construction project management, this paper presents the results of a case study of a typical road construction project where the combined use of the two technologies was used in order to achieve efficient and accurate as-built data collection of the works progress, with outcomes such as volumes, and production of sections and 3D models, information necessary in project progress monitoring and efficient project management.

Keywords: BIM, project management, project monitoring, UAV

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4882 Isolation and Identification Fibrinolytic Protease Endophytic Fungi from Hibiscus Leaves in Shah Alam

Authors: Mohd Sidek Ahmad, Zainon Mohd Noor, Zaidah Zainal Ariffin

Abstract:

Fibrin degradation is an important part in prevention or treatment of intravascular thrombosis and cardiovascular diseases. Plasmin like fibrinolytic enzymes has given new hope to patient with cardiovascular diseases by treating fibrin aggregation related diseases with traditional plasminogen activator which have many side effects. Various researches involving wide range of sources for production of fibrinolytic proteases, from bacteria, fungi, insects and fermented foods. But few have looked into endophytic fungi as a potential source. Sixteen (16) endophytic fungi were isolated from Hibiscus sp. leaves from six different locations in Shah Alam, Selangor. Only two endophytic fungi, FH3 and S13 showed positive fibrinolytic protease activities. FH3 produced 5.78cm and S13 produced 4.48cm on Skim Milk Agar after 4 days of incubation at 27°C. Fibrinolytic activity was observed; 3.87cm and 1.82cm diameter clear zone on fibrin plate of FH3 and S13 respectively. 18srRNA was done for identification of the isolated fungi with positive fibrinolytic protease. S13 had the highest similarity (100%) to that of Penicillium citrinum strain TG2 and FH3 had the highest similarity (99%) to that of Fusarium sp. FW2PhC1, Fusarium sp. 13002, Fusarium sp. 08006, Fusarium equiseti strain Salicorn 8 and Fungal sp. FCASAn-2. Media composition variation showed the effects of carbon nitrogen on protein concentration, where the decrement of 50% of media composition caused drastic decrease in protease of FH3 from 1.081 to 0.056 and also S13 from 2.946 to 0.198.

Keywords: isolation, identification, fibrinolytic protease, endophytic fungi, Hibiscus leaves

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4881 Forest Risk and Vulnerability Assessment: A Case Study from East Bokaro Coal Mining Area in India

Authors: Sujata Upgupta, Prasoon Kumar Singh

Abstract:

The expansion of large scale coal mining into forest areas is a potential hazard for the local biodiversity and wildlife. The objective of this study is to provide a picture of the threat that coal mining poses to the forests of the East Bokaro landscape. The vulnerable forest areas at risk have been assessed and the priority areas for conservation have been presented. The forested areas at risk in the current scenario have been assessed and compared with the past conditions using classification and buffer based overlay approach. Forest vulnerability has been assessed using an analytical framework based on systematic indicators and composite vulnerability index values. The results indicate that more than 4 km2 of forests have been lost from 1973 to 2016. Large patches of forests have been diverted for coal mining projects. Forests in the northern part of the coal field within 1-3 km radius around the coal mines are at immediate risk. The original contiguous forests have been converted into fragmented and degraded forest patches. Most of the collieries are located within or very close to the forests thus threatening the biodiversity and hydrology of the surrounding regions. Based on the vulnerability values estimated, it was concluded that more than 90% of the forested grids in East Bokaro are highly vulnerable to mining. The forests in the sub-districts of Bermo and Chandrapura have been identified as the most vulnerable to coal mining activities. This case study would add to the capacity of the forest managers and mine managers to address the risk and vulnerability of forests at a small landscape level in order to achieve sustainable development.

Keywords: forest, coal mining, indicators, vulnerability

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4880 Evaluation and Selection of Elite Jatropha Genotypes for Biofuel

Authors: Bambang Heliyanto, Rully Dyah Purwati, Hasnam, Fadjry Djufry

Abstract:

Jatropha curcas L., a drought tolerant and monoecious perennial shrub, has received attention worldwide during the past decade. Realizing the facts, the Indonesian government has decided to option for Jatropha and palm oil for in country biofuel production. To support the program development of high yielding jatropha varieties is necessary. This paper reviews Jatropha improvement program in Indonesia using mass selection and hybrid development. To start with, at the end of 2005, in-country germplasm collection was mobilized to Lampung and Nusa Tenggara Barat (NTB) provinces and successfully collected 15 provenances/sub-provenances which serves as a base population for selection. A significant improvement has been achieved through a simple recurrent breeding selection during 2006 to 2007. Seed yield productivity increased more than double, from 0.36 to 0.97 ton dry seed per hectare during the first selection cycle (IP-1), and then increased to 2.2 ton per hectare during the second cycles (IP-2) in Lampung provenance. Similar result was also observed in NTB provenance. Seed yield productivity increased from 0.43 ton to 1 ton dry seed per hectare in the first cycle (IP-1), and then 1.9 ton in the second cycle (IP-2). In 2008, the population IP-3 resulted from the third cycle of selection have been identified which were capable of producing 2.2 to 2.4 ton seed yield per hectare. To improve the seed yield per hectare, jatropha hybrid varieties was developed involving superior provenances. As a result a Jatropha Energy Terbarukan (JET) variety-2 was released in 2017 with seed yield potential of 2.6 ton per hectare. The use of this high yielding genotypes for biofuel is discussed.

Keywords: Jatropha curcas, provenance, biofuel, improve population, hybrid

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4879 Analysis of the Fire Hazard Posed by Petrol Stations in Stellenbosch and the Extent to Which Planning Acknowledges Risk

Authors: Kwanele Qonono

Abstract:

Despite the significance and economic benefits of petrol stations in South Africa, these still pose a huge risk of fire and explosion threatening public safety. This research paper examines the extent to which land-use planning in Stellenbosch, South Africa, considers the fire risk posed by petrol stations and the implications for public safety as well as preparedness for large fires or explosions. To achieve this, the research identified the land-use types around petrol stations in Stellenbosch and determined the extent to which their locations comply with the local, national, and international land-use planning regulations. A mixed research method consisting of the collection and analysis of geospatial data and qualitative data was an applied method, where petrol stations within a six-kilometre radius of Stellenbosch’s town centre were utilised as study sites. The research examined the risk of fires/explosions at these petrol stations. The research investigated Stellenbosch Municipality’s institutional preparedness to respond in the event of a fire/explosion at these petrol stations. The research observed that siting of petrol stations does not comply with local, national, and international good practices, thus exposing the surrounding developments to fires and explosions. Land-use planning practice does not consider hazards created by petrol stations. Despite the potential for major fires at petrol stations, Stellenbosch Municipality’s level of preparedness to respond to petrol station fires appears low due to the prioritisation of more frequent events.

Keywords: petrol stations, technological hazard, drr, land-use planning, risk analysis

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4878 Waters Colloidal Phase Extraction and Preconcentration: Method Comparison

Authors: Emmanuelle Maria, Pierre Crançon, Gaëtane Lespes

Abstract:

Colloids are ubiquitous in the environment and are known to play a major role in enhancing the transport of trace elements, thus being an important vector for contaminants dispersion. Colloids study and characterization are necessary to improve our understanding of the fate of pollutants in the environment. However, in stream water and groundwater, colloids are often very poorly concentrated. It is therefore necessary to pre-concentrate colloids in order to get enough material for analysis, while preserving their initial structure. Many techniques are used to extract and/or pre-concentrate the colloidal phase from bulk aqueous phase, but yet there is neither reference method nor estimation of the impact of these different techniques on the colloids structure, as well as the bias introduced by the separation method. In the present work, we have tested and compared several methods of colloidal phase extraction/pre-concentration, and their impact on colloids properties, particularly their size distribution and their elementary composition. Ultrafiltration methods (frontal, tangential and centrifugal) have been considered since they are widely used for the extraction of colloids in natural waters. To compare these methods, a ‘synthetic groundwater’ was used as a reference. The size distribution (obtained by Field-Flow Fractionation (FFF)) and the chemical composition of the colloidal phase (obtained by Inductively Coupled Plasma Mass Spectrometry (ICPMS) and Total Organic Carbon analysis (TOC)) were chosen as comparison factors. In this way, it is possible to estimate the pre-concentration impact on the colloidal phase preservation. It appears that some of these methods preserve in a more efficient manner the colloidal phase composition while others are easier/faster to use. The choice of the extraction/pre-concentration method is therefore a compromise between efficiency (including speed and ease of use) and impact on the structural and chemical composition of the colloidal phase. In perspective, the use of these methods should enhance the consideration of colloidal phase in the transport of pollutants in environmental assessment studies and forensics.

Keywords: chemical composition, colloids, extraction, preconcentration methods, size distribution

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4877 Physical Activity Patterns during Inpatient Rehabilitation in Patients with Recent Brain Injury

Authors: Nikita Pasricha, Karen Smith, Simone Marshall, Vincent DePaul, Jessica Trier

Abstract:

Understanding that physical activity in rehabilitation programs shapes outcomes in acquired brain injury (ABI) populations is not a new concept. However, there is a void in understanding the physical activity patterns of inpatients in ABI rehabilitation, the trajectory of physical activity recovery, and factors that contribute to the recovery of physical activity over the initial months post-ABI. The purpose of this study was to determine if physical activity patterns vary in people with recent ABI in inpatient rehabilitation. The study also investigated differences in physical activity patterns in ABI patients compared to age-related healthy participants. Results revealed that ABI patients spent approximately 6.7 times longer per day in sedentary postures than in active positions. In comparison, the control group spent only 2.8 times longer in sedentary postures compared to active positions. Patients with ABI took significantly fewer steps than age-matched health control participants. Within the ABI population, patients took 0.78 times fewer steps on weekends compared to weekdays. Participants with greater mobility limitations had a greater difference in WD to WE steps taken. Potential reasons could be from no structured weekend rehabilitation programs, lower availability of staff, or varying schedules. Given that the rehabilitation program is only structured on weekdays, further research to investigate the benefits of structured physical activities like group walking programs on weekends for ABI patients in inpatient rehabilitation programs is warranted.

Keywords: brain, ABI, TBI, rehabilitation

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4876 Preparation of Fe3Si/Ferrite Micro-and Nano-Powder Composite

Authors: Radovan Bures, Madgalena Streckova, Maria Faberova, Pavel Kurek

Abstract:

Composite material based on Fe3Si micro-particles and Mn-Zn nano-ferrite was prepared using powder metallurgy technology. The sol-gel followed by autocombustion process was used for synthesis of Mn0.8Zn0.2Fe2O4 ferrite. 3 wt.% of mechanically milled ferrite was mixed with Fe3Si powder alloy. Mixed micro-nano powder system was homogenized by the Resonant Acoustic Mixing using ResodynLabRAM Mixer. This non-invasive homogenization technique was used to preserve spherical morphology of Fe3Si powder particles. Uniaxial cold pressing in the closed die at pressure 600 MPa was applied to obtain a compact sample. Microwave sintering of green compact was realized at 800°C, 20 minutes, in air. Density of the powders and composite was measured by Hepycnometry. Impulse excitation method was used to measure elastic properties of sintered composite. Mechanical properties were evaluated by measurement of transverse rupture strength (TRS) and Vickers hardness (HV). Resistivity was measured by 4 point probe method. Ferrite phase distribution in volume of the composite was documented by metallographic analysis. It has been found that nano-ferrite particle distributed among micro- particles of Fe3Si powder alloy led to high relative density (~93%) and suitable mechanical properties (TRS >100 MPa, HV ~1GPa, E-modulus ~140 GPa) of the composite. High electric resistivity (R~6.7 ohm.cm) of prepared composite indicate their potential application as soft magnetic material at medium and high frequencies.

Keywords: micro- and nano-composite, soft magnetic materials, microwave sintering, mechanical and electric properties

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4875 Architectural Experience of the Everyday in Bangkok CBD

Authors: Thirayu Jumsai Na Ayudhya

Abstract:

The attempt to understand about what architecture means to people as they go about their everyday life revealed that knowledge such as environmental psychology, environmental perception, environmental aesthetics, inadequately address the contextualized and holistic theoretical framework. In my previous research, it was found that people’s making senses of their everyday architecture can be addressed in terms of four super‐ordinate themes; (1) building in urban (text), (2) building in (text), (3) building in human (text), (4) and building in time (text). In this research, Bangkok CBD was selected as the focal urban context that the integrated style of architecture is noticeable. It is expected that in a unique urban context like Bangkok CBD unprecedented super-ordinate themes will be unveiled through the reflection of people’s everyday experiences. In this research, people’s architectural experience conducted in Bangkok CBD, Thailand, will be presented succinctly. The research addresses the question of how do people make sense of their everyday architecture/buildings especially in a unique urban context, Bangkok CBD, and identifies ways in which people make sense of their everyday architecture. Two key methodologies are adopted. First, Participant-Produced-Photograph (PPP) allows people to express their experiences of the everyday urban context freely without any interference or forced-data generating by researchers. Second, Interpretative Phenomenological Analysis (IPA) are also applied as main methodologies. With IPA methodology, a small pool of participants is considered giving the detailed level of analysis and its potential to produce a meaningful outcome.

Keywords: architectural experience, building appreciation, design psychology, environmental psychology, sense-making, the everyday experience, transactional theory

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4874 Investigation of Wood Chips as Internal Carbon Source Supporting Denitrification Process in Domestic Wastewater Treatment

Authors: Ruth Lorivi, Jianzheng Li, John J. Ambuchi, Kaiwen Deng

Abstract:

Nitrogen removal from wastewater is accomplished by nitrification and denitrification processes. Successful denitrification requires carbon, therefore, if placed after biochemical oxygen demand (BOD) and nitrification process, a carbon source has to be re-introduced into the water. To avoid adding a carbon source, denitrification is usually placed before BOD and nitrification processes. This process however involves recycling the nitrified effluent. In this study wood chips were used as internal carbon source which enabled placement of denitrification after BOD and nitrification process without effluent recycling. To investigate the efficiency of a wood packed aerobic-anaerobic baffled reactor on carbon and nutrients removal from domestic wastewater, a three compartment baffled reactor was presented. Each of the three compartments was packed with 329 g wood chips 1x1cm acting as an internal carbon source for denitrification. The proposed mode of operation was aerobic-anoxic-anaerobic (OAA) with no effluent recycling. The operating temperature, hydraulic retention time (HRT), dissolved oxygen (DO) and pH were 24 ± 2 , 24 h, less than 4 mg/L and 7 ± 1 respectively. The removal efficiencies of chemical oxygen demand (COD), ammonia nitrogen (NH4+-N) and total nitrogen (TN) attained was 99, 87 and 83% respectively. TN removal rate was limited by nitrification as 97% of ammonia converted into nitrate and nitrite was denitrified. These results show that application of wood chips in wastewater treatment processes is an efficient internal carbon source. 

Keywords: aerobic-anaerobic baffled reactor, denitrification, nitrification, wood chip

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4873 Association of Human Immunodeficiency Virus with Incident Autoimmune Hemolytic Anemia: A Population-Based Cohort Study in Taiwan

Authors: Yung-Feng Yen, I-an Jen, Yi-Ming Arthur Chen

Abstract:

The molecular mimicry between human immunodeficiency virus (HIV) protein and red blood cell (RBC) antigens could induce the production of anti-RBC autoantibodies. However, the association between HIV infection and subsequent development of autoimmune hemolytic anemia (AIHA) remains unclear. This nationwide population-based cohort study aimed to determine the association between incident AIHA and HIV in Taiwan. From 2000–2012, we identified adult people living with HIV/AIDS (PLWHA) from the Taiwan centers for disease control HIV Surveillance System. HIV-infected individuals were defined by positive HIV-1 western blot. Age- and sex-matched controls without HIV infection were selected from the Taiwan National Health Insurance Research Database for comparison. All patients were followed until Dec. 31, 2012, and observed for occurrence of AIHA. Of 171,468 subjects (19,052 PLWHA, 152,416 controls), 30 (0.02%) had incident AIHA during a mean follow-up of 5.45 years, including 23 (0.12%) PLWHA and 7 (0.01%) controls. After adjusting for potential confounders, HIV infection was found to be an independent risk factor of incident AIHA (adjusted hazard ratio [AHR], 20.9; 95% confidence interval [CI], 8.34-52.3). Moreover, PLWHA receiving HAART were more likely to develop AIHA than those not receiving HAART (AHR, 10.8; 95% CI, 2.90-40.1). Additionally, the risk of AIHA was significantly increased in those taking efavirenz (AHR, 3.15; 95% CI, 1.18-8.43) or atazanavir (AHR, 6.58; 95% CI, 1.88-22.9) component of the HAART. In conclusion, HIV infection is an independent risk factor for incident AIHA. Clinicians need to be aware of the higher risk of AIHA in PLWHA.

Keywords: autoimmune disease , hemolytic anemia, HIV, highly active antiretroviral treatment

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4872 Moral Identity and Moral Attentiveness as Predictors of Ethical Leadership in Financial Sector

Authors: Pilar Gamarra Gamarra, Michele Girotto

Abstract:

In the expanding field of leaders’ ethical behavior research, little attention has been paid to the association between finance leaders’ ethical traits (beyond personality) and ethical leadership, and more importantly, how these ethical characteristics can be predictors of ethical behavior at the leadership level in the financial sector. In this study, we tested a theoretical model based on uponsocial cognitive theory (Bandura, 1986) and the cognitive-developmental model (Piaget, 1932) to examine leaders’ moral identity and moral attentiveness as antecedents of ethical leadership. After the 2008 economic crisis, the marketplace has awakened to the potential dangers of unethical behavior. The unethical behavior of the leaders of the financial sector was identified as guilty of this economic catastrophe. For that reason, it seems increasingly prudent for organizations to have leaders who are cognitively inclined toward ethical behavior. This evidence suggests that moral attentiveness and moral identity is perhaps one way of identifying those kinds of leaders. For leaders who are morally attentive and have a high moral identity, themes of ethics interventions are consistent with their way of seeing the word. As a result, these leaders could become critical components of change in organizations and could provide the energy and skills necessary for these efforts to be successful. Ethical behavior of leader from the financial sector and marketing sectors must be joined to manage the change. In this study, a leader’s moral identity, leader’s moral attentiveness, and self-importance of Ethical Leadership are measured for financial and marketing leaders to be compared to determine the relationship between the three variables in each sector. Other conclusion related to gender, educational level or generation are obtained.

Keywords: ethical leadership, moral identity, moral attentiveness, financial leaders, marketing leaders, ethical behavior

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4871 Effect of Nicotine on the Reinforcing Effects of Cocaine in a Nonhuman Primate Model of Drug Use

Authors: Mia I. Allen, Bernard N. Johnson, Gagan Deep, Yixin Su, Sangeeta Singth, Ashish Kumar, , Michael A. Nader

Abstract:

With no FDA-approved treatments for cocaine use disorders (CUD), research has focused on the behavioral and neuropharmacological effects of cocaine in animal models, with the goal of identifying novel interventions. While the majority of people with CUD also use tobacco/nicotine, the majority of preclinical cocaine research does not include the co-use of nicotine. The present study examined nicotine and cocaine co-use under several conditions of intravenous drug self-administration in monkeys. In Experiment 1, male rhesus monkeys (N=3) self-administered cocaine (0.001-0.1 mg/kg/injection) alone and cocaine+nicotine (0.01-0.03 mg/kg/injection) under a progressive-ratio schedule of reinforcement. When nicotine was added to cocaine, there was a significant leftward shift and significant increase in peak break point. In Experiment 2, socially housed female and male cynomolgus monkeys (N=14) self-administered cocaine under a concurrent drug-vs-food choice schedule. Combining nicotine significantly decreased cocaine choice ED50 values (i.e., shifted the cocaine dose-response curve to the left) in females but not in males. There was no evidence of social rank differences. In delay discounting studies, the co-use of nicotine and cocaine required significantly larger delays to the preferred drug reinforcer to reallocate choice compared with cocaine alone. Overall, these results suggest drug interactions of nicotine and cocaine co-use is not simply a function of potency but rather a fundamentally distinctive condition that should be utilized to better understand the neuropharmacology of CUD and the evaluation of potential treatments.

Keywords: polydrug use, animal models, nonhuman primates, behavioral pharmacology, drug self-administration

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4870 Chatbots as Language Teaching Tools for L2 English Learners

Authors: Feiying Wu

Abstract:

Chatbots are computer programs that attempt to engage a human in a dialogue, which originated in the 1960s with MIT's Eliza. However, they have become widespread more recently as advances in language technology have produced chatbots with increasing linguistic quality and sophistication, leading to their potential to serve as a tool for Computer-Assisted Language Learning(CALL). The aim of this article is to assess the feasibility of using two chatbots, Mitsuku and CleverBot, as pedagogical tools for learning English as a second language by stimulating L2 learners with distinct English proficiencies. Speaking of the input of stimulated learners, they are measured by AntWordProfiler to match the user's expected vocabulary proficiency. Totally, there are four chat sessions as each chatbot will converse with both beginners and advanced learners. For evaluation, it focuses on chatbots' responses from a linguistic standpoint, encompassing vocabulary and sentence levels. The vocabulary level is determined by the vocabulary range and the reaction to misspelled words. Grammatical accuracy and responsiveness to poorly formed sentences are assessed for the sentence level. In addition, the assessment of this essay sets 25% lexical and grammatical incorrect input to determine chatbots' corrective ability towards different linguistic forms. Based on statistical evidence and illustration of examples, despite the small sample size, neither Mitsuku nor CleverBot is ideal as educational tools based on their performance through word range, grammatical accuracy, topic range, and corrective feedback for incorrect words and sentences, but rather as a conversational tool for beginners of L2 English.

Keywords: chatbots, CALL, L2, corrective feedback

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4869 Examining the Factors That Mediate the Effects of Mindfulness on Conflict Resolution Strategies

Authors: Franco Ceasar Agbalog, Shintaro Yukawa

Abstract:

Mindfulness is increasingly being used as a method for resolving conflict. However, less is known about how its positive outcome develops. To better understand the underlying effects of mindfulness on conflict resolution strategies, this study examines the potential mediating factors between them. The researchers hypothesized that Emotional Intelligence (EI) mediates the effects of mindfulness on conflict resolution strategies due to its similar components to the benefits of mindfulness, such as awareness and control of one’s emotions, awareness and understanding of other’s emotions, and cultivation of compassion and empathy. Using a random sampling, 157 participants completed three questionnaires: Five Facet Mindfulness Questionnaire (FFMQ), Trait Emotional Intelligence Questionnaire-Short Form (TEIQue-SF), and Rahim Organizational Conflict Inventory-II (ROCI-II). Utilizing the SPSS Process, results showed a significant relationship between mindfulness and EI. However, among the five approaches to conflict resolution, only the integrating style was significantly related to EI. Following the principle of Mediation Analysis, mindfulness has an indirect effect on integrating style. Moreover, mindfulness and conflict resolution strategies were not significantly related. This is a rather surprising result because research literature has always indicated a positive relationship between the two variables. These findings imply that although integrating style is generally considered the best approach in handling conflict, each style may be appropriate depending on the situation. Mindfulness allows practitioners to have a holistic view of the conflict situation and choose the approach they think best for that specific situation. This could explain why statistically, there is no direct effect of mindfulness on conflict resolution strategies. This work provides basis for the necessity to investigate the factors of conflict instead of the conflict resolution strategies; factors that can be manipulated and may be directly influenced by mindfulness.

Keywords: conflict resolution strategies, emotional intelligence, mindfulness and conflict, ROCI-II integrating style

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4868 In vitro Assessment of Bioactive Properties and Dose-Dependent Antioxidant Activities of Commercial Grape Cultivars in Taiwan

Authors: Kandi Sridhar, Charles Albert Linton

Abstract:

Grapes are excellent sources of bioactive compounds, which have been suggested to be responsible for lowering the risk of chronic diseases. Fresh and freeze-dried extracts of Kyoho and Jubilee, commercial grape varieties available in Taiwan and attractive for their quality berries, were investigated for their total phenolics and total flavonoids contents and related dose-dependent antioxidants properties using various in vitro assays. The efficiency of the extraction yield ranged from 7.10 % to 25.53 % (w/w), depending on solvent used. Fresh samples of Kyoho and Jubilee exhibited total polyphenolic contents (351.56 ± 23.08 and 328.67 ± 16.54 µg GAE/mL, respectively), whereas Kyoho freeze-dried methanol: water extracts contains the good levels of total flavonoids (4767.82 ± 22.20 µg QE/mL). Kyoho and Jubilee freeze-dried extracts exhibited the highest total flavonoid contents. There was a weak correlation between total phenolic and flavonoid assays (r= -0.05, R2 = 0.02, p > 0.05). Kyoho fresh and freeze-dried samples showed the DPPH (11.51 – 77.82 %), superoxide scavenging activity (33.61 – 81.95 %), and total antioxidant inhibition (92.01 – 99.28 %), respectively. Total flavonoids were statistically correlated with EC50 DPPH scavenging radicals (r =0.91, p < 0.01), EC50 nitric oxide (r = 0.25, p > 0.05), and EC50 lipid peroxidation radicals (r = 0.38, p > 0.05). These results suggested that the two commercial grape cultivars in Taiwan could be used as a good source of natural antioxidants. Thus, consumption of grapes as a source antioxidant might lower the risk of chronic diseases. Moreover, future studies will investigate and develop phenolic acid profile for the cultivars in Taiwan.

Keywords: antioxidants, EC50 radical scavenging activity, grape cultivars, total phenolics

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4867 Antibacterial Activity of Silver Nanoparticles of Extract of Leaf of Nauclea latifolia (Sm.) against Some Selected Clinical Isolates

Authors: Mustapha Abdulsalam, R. N. Ahmed

Abstract:

Nauclea latifolia is one of the medicinal plants used in traditional Nigerian medicine in the treatment of various diseases such as fever, toothaches, malaria, diarrhea among several other conditions. Nauclea latifolia leaf extract acts as a capping and reducing agent in the formation of silver nanoparticles. Silver nanoparticles (AgNPs) were synthesized using a combination of aqueous extract of Nauclea latifolia and 1mM of silver nitrate (AgNO₃) solution to obtain concentrations of 100mg/ml-400mg/ml. Characterization of the particles was done by UV-Vis spectroscopy and Fourier transform infrared (FTIR). In this study, aqueous as well as ethanolic extract of leaf of Nauclea latifolia were investigated for antibacterial activity using the standard agar well diffusion technique against three clinical isolates (Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa). The Minimum Inhibitory Concentration (MIC) was achieved by microbroth dilution method and Minimum Bactericidal Concentration (MBC) was also determined by plate assay. Characterization by UV-visible spectrometry revealed peak absorbance of 0.463 at 450.0nm, while FTIR showed the presence of two functional groups. At 400mg/ml, the highest inhibitory activities were observed with S.aureus and E.coli with zones of inhibition measuring 20mm and 18mm respectively. The MIC was obtained at 400mg/ml while MBC was at a higher concentration. The data from this study indicate the potential of silver nanoparticle of Nauclea latifolia as a suitable alternative antibacterial agent for incorporation into orthodox medicine in health care delivery in Nigeria.

Keywords: agar well diffusion, antimicrobial activity, Nauclea latifolia, silver nanoparticles

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4866 Experimental Validation of Computational Fluid Dynamics Used for Pharyngeal Flow Patterns during Obstructive Sleep Apnea

Authors: Pragathi Gurumurthy, Christina Hagen, Patricia Ulloa, Martin A. Koch, Thorsten M. Buzug

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Obstructive sleep apnea (OSA) is a sleep disorder where the patient suffers a disturbed airflow during sleep due to partial or complete occlusion of the pharyngeal airway. Recently, numerical simulations have been used to better understand the mechanism of pharyngeal collapse. However, to gain confidence in the solutions so obtained, an experimental validation is required. Therefore, in this study an experimental validation of computational fluid dynamics (CFD) used for the study of human pharyngeal flow patterns during OSA is performed. A stationary incompressible Navier-Stokes equation solved using the finite element method was used to numerically study the flow patterns in a computed tomography-based human pharynx model. The inlet flow rate was set to 250 ml/s and such that a flat profile was maintained at the inlet. The outlet pressure was set to 0 Pa. The experimental technique used for the validation of CFD of fluid flow patterns is phase contrast-MRI (PC-MRI). Using the same computed tomography data of the human pharynx as in the simulations, a phantom for the experiment was 3 D printed. Glycerol (55.27% weight) in water was used as a test fluid at 25°C. Inflow conditions similar to the CFD study were simulated using an MRI compatible flow pump (CardioFlow-5000MR, Shelley Medical Imaging Technologies). The entire experiment was done on a 3 T MR system (Ingenia, Philips) with 108 channel body coil using an RF-spoiled, gradient echo sequence. A comparison of the axial velocity obtained in the pharynx from the numerical simulations and PC-MRI shows good agreement. The region of jet impingement and recirculation also coincide, therefore validating the numerical simulations. Hence, the experimental validation proves the reliability and correctness of the numerical simulations.

Keywords: computational fluid dynamics, experimental validation, phase contrast-MRI, obstructive sleep apnea

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4865 Targeting NLRP3 Inflammasome Activation: A New Mechanism Underlying the Protective Effects of Nafamostat Against Acute Pancreatitis

Authors: Jiandong Ren, Lijun Zhao, Peng Chen

Abstract:

Nafamostat (NA), a synthetic broad-spectrum serine protease inhibitor, has been routinely employed for the treatment of acute pancreatitis (AP) and other inflammatory-associated diseases in some East Asia countries. Although the potent inhibitory activity against inflammation-related proteases such as thrombin, trypsin, kallikrein, plasmin, coagulation factors and complement factors is generally considered to be responsible for the anti-inflammatory effects of NA, precise target and molecular mechanism underlying the anti-inflammatory activity in the treatment of AP remain largely unknown yet. As an intracellular inflammatory signaling platform, the NOD-like receptor protein 3 (NLRP3) inflammasome is recently identified to be involved in the development of AP. In present study, we have revealed that NA alleviated pancreatic injury in a caerulein-induced AP model by inhibiting the NLRP3 inflammasome activation in pancreas. Mechanistically, NA interacted with HDAC6, a cytoplasmic deacetylase implicated in the NLRP3 inflammasome pathway, and efficiently abrogated the function of HDAC6. This property enabled NA to influence HDAC6 dependent NF-κB transcriptional activity and thus block NF-κB-driven transcriptional priming of NLRP3 inflammasome. Moreover, NA exerted the potential to interfere HDAC6-mediated intracellular transport of NLRP3, thereby leading to the failure of NLRP3 inflammasome activation. Our current work has provided valuable insight into the molecular mechanism underlying the immunomodulatory effect of NA in treatment of AP, highlighting its promising application in prevention of NLRP3 inflammasome-associated inflammatory pathological damage.

Keywords: acute pancreatitis, HDAC6, nafamostat, NLRP3 inflammasome

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4864 Niftiness of the COLME to Promote Shared Decision-Making in Organizations

Authors: Prakash Singh

Abstract:

The question that arises is whether a theory such as the Collegial Leadership Model of Emancipation (COLME) has the potency to introduce leadership change by empowering and emancipating their employees. It is a fallacy to simply assume that experience alone, in the absence of theory, will contribute to this knowledge base to develop collegial leaders. The focus of this study is to therefore ascertain whether the COLME can serve as a conceptual framework to transform traditional bureaucratic management practices (TBMPs) in order to promote shared decision-making in organizations such as schools. All the respondents in this exploratory qualitative study embraced collegiality to transform TBMPs in their organizations. For the positive effects to be sustained, the collegial practices need to be evolutionary and emancipatory in order to evoke the values of collegial leadership as elucidated by the findings of this study. Interviewees affirmed that the COLME provides an astute framework to develop commendable collegial leadership practices as it clearly outlines procedures to develop and use the leadership potential of all the employees in order to foster joint accountability. They acknowledged that when the principles of collegiality are flexibly applied, they contribute to the creation of a holistic milieu in which all employees are able to express themselves freely, without fear of failure, and thus feel that they are part of the democratic decision-making process. Evidently, a conceptual framework such as the COLME can serve as a benchmark for leadership effectiveness because organizational outcomes need to be measured against standards of excellence in meeting both employee and customer expectations.

Keywords: collegial leadership model, employee empowerment, shared decision-making, traditional bureaucratic management practices

Procedia PDF Downloads 479
4863 Temperature Control and Comfort Level of Elementary School Building with Green Roof in New Taipei City, Taiwan

Authors: Ying-Ming Su, Mei-Shu Huang

Abstract:

To mitigate the urban heat island effect has become a global issue facing the challenge of climate change. Through literature reviews, plant photosynthesis can reduce the carbon dioxide and mitigate the urban heat island effect relatively. Because there are not enough open space and park, green roof has become an important policy in Taiwan. We selected elementary school buildings in northern New Taipei City as research subjects since elementary school is asked priority to build green roof and important educational place to promote green roof concept. Testo 175-H1 recording device was used to record the temperature and humidity difference between roof surface and interior space below roof with and without green roof for the long-term. We also use questionnaire to investigate the awareness of comfort level of green roof and sensation of teachers and students of the elementary school. The results indicated the temperature of roof without greening was higher than that with greening about 2°C. But sometimes during noontime, the temperature of green roof was higher than that of non-green roof related to the character of the accumulation and dissipation of heat of greening probably. The temperature of interior space below green roof was normally lower than that without green roof about 1°C showed that green roof could lower the temperature. The humidity of the green roof was higher than the one without greening also indicated that green roof retained water better. Teachers liked to combine green roof concept in the curriculum, students wished all classes can take turns to maintain the green roof. Teachers and students that school had integrated green roof concept in the curriculum were more willing to participate in the maintenance work of green roof. Teachers and students who may access and touch the green roof can be more aware of the green roof benefit. We suggest architect to increase the accessibility and visibility of green roof, such as a part of the activity space. This idea can be a reference of the green roof curriculum design.

Keywords: comfort level, elementary school, green roof, heat island effect

Procedia PDF Downloads 405
4862 Development of Surface Modification Technology for Control Element Drive Mechanism Nozzle and Fatigue Enhancement of Ni-Based Alloys

Authors: Auezhan Amanov, Inho Cho, Young-Sik Pyun

Abstract:

Control element drive mechanism (CEDM) nozzle is manufactured as welded on the reactor vessel and currently uses Alloy 690 material. The top of the reactor is equipped with about 100 CEDM nozzles with an internal diameter of about 70 mm. Relatively large Inlet/Outlet nozzles are equipped with two outlet nozzles and four inlet nozzles on the reactor wall. The inner diameter of the nozzle is vulnerable to stress corrosion cracking (SCC), and in order to solve this problem, an ultrasonic nanocrystal surface modification (UNSM) treatment is performed on the inner diameter of the nozzle and the weld surface. The ultimate goal is to improve the service life of parts by applying compressive residual stress and suppressing primary water stress corrosion cracking (PWSCC). The main purpose is to design and fabricate a UNSM treatment device for the internal diameter processing of CEDM nozzles and inlet/outlet nozzles. In order to develop the system, the basic technology such as the development of UNSM tooling is developed and the mechanical properties and fatigue performance of before and after UNSM treatment of reactor nozzle material made of Ni-based alloys using the specimen are compared and evaluated. The inner diameter of the nozzle was treated by a newly developed UNSM treatment under the optimized treatment parameters. It was found that the mechanical properties and fatigue performance of nozzle were improved in comparison with the untreated nozzle, which may be attributed to the increase in hardness, induced compressive residual stress.

Keywords: control element drive mechanism nozzle, fatigue, Ni-based alloy, ultrasonic nanocrystal surface modification, UNSM

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4861 Effect of Particle Size and Concentration of Pomegranate (Punica granatum l.) Peel Powder on Suppression of Oxidation of Edible Plant Oils

Authors: D. G. D. C. L. Munasinghe, M. S. Gunawardana, P. H. P. Prasanna, C. S. Ranadheera, T. Madhujith

Abstract:

Lipid oxidation is an important process that affects the shelf life of edible oils. Oxidation produces off flavors, off odors and chemical compounds that lead to adverse health effects. Chemical mechanisms such as autoxidation, photo-oxidation and thermal oxidation are responsible for lipid oxidation. Refined, Bleached and Deodorized (RBD) coconut oil, Virgin Coconut Oil (VCO) and corn oil are widely used plant oils. Pomegranate fruit is known to possess high antioxidative efficacy. Peel of pomegranate contains high antioxidant activity than aril and pulp membrane. The study attempted to study the effect of particle size and concentration of pomegranate peel powder on suppression of oxidation of RBD coconut oil, VCO and corn oil. Pomegranate peel powder was incorporated into each oil sample as micro (< 250 µm) and nano particles (280 - 300 nm) at 100 ppm and 200 ppm concentrations. The control sample of each oil was prepared, devoid of pomegranate peel powder. The stability of oils against autoxidation was evaluated by storing oil samples at 60 °C for 28 days. The level of oxidation was assessed by peroxide value and thiobarbituric acid reactive substances on 0,1,3,5,7,14 and 28 day, respectively. VCO containing pomegranate particles of 280 - 300 nm at 200 ppm showed the highest oxidative stability followed by RBD coconut oil and corn oil. Results revealed that pomegranate peel powder with 280 - 300 nm particle size at 200 ppm concentration was the best in mitigating oxidation of RBD coconut oil, VCO and corn oil. There is a huge potential of utilizing pomegranate peel powder as an antioxidant agent in reducing oxidation of edible plant oils.

Keywords: antioxidant, autoxidation, micro particles, nano particles, pomegranate peel powder

Procedia PDF Downloads 441
4860 First Breeding Populations of The Glossy Ibis (Plegadis falcinellus) in a Peri-Urban Wetland Areas (Marsh of Boussedra; North-East of Algeria)

Authors: Boudraa Wahiba, Chettibi Farah, Lahlah Naouel, Bouslama Zihad, Houhamdi Moussa

Abstract:

The marsh of Boussedra (55 ha) is a peri-urban wetland, located in the city of El - Bouni, wilaya of Annaba (North-east of the Algeria). This city hosts every year, 53 species of waterfowl, belonging to 15 different families, of which the most represented family is the Anatidae with almost 12 species. The Glossy ibis (Plegadis falcinellus) is the only representative of the family of the threskiornithidae. After a total absence for almost a decade, this species has established in North Africa and started breeding since 2000. The Glossy ibis (plegadis falcinellus), breeds with low numbers in distant areas. At the wetland of Boussedra, the population of this species was observed with numbers approaching 160 individuals. During the breeding season of 2014 (between march and july), this species bred in mixed heronries (Cattle egret Bubulcus ibis , Little egret Egretta garzetta, The black-crowned night heron Nycticorax nycticorax , Squacco heron Ardeola ralloides and Little bittern Ixobrychus minutus), where a total of 120 nests were counted. This represents the largest colony observed in North Africa. The reproduction of the studied species took place on a Tamaricaceae (Tamarix gallica), where more than 2000 nest were constructed. During this breeding season, we have monitored the colony's installation and evolution and tried to characterize the reproduction, at the urban water plan of Boussedra (measurements of nests, measurements of eggs and monitoring the growing rate and weight gaining of the chicks, since their birth until their flight).

Keywords: glossy ibis, reproduction, peri-urban wetland, mixed heronry, Boussedra, Algeria

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4859 Hope as a Predictor for Complicated Grief and Anxiety: A Bayesian Structural Equational Modeling Study

Authors: Bo Yan, Amy Y. M. Chow

Abstract:

Bereavement is recognized as a universal challenging experience. It is important to gather research evidence on protective factors in bereavement. Hope is considered as one of the protective factors in previous coping studies. The present study aims to add knowledge by investigating hope at the first month after death to predict psychological symptoms altogether including complicated grief (CG), anxiety, and depressive symptoms at the seventh month. The data were collected via one-on-one interview survey in a longitudinal project with Hong Kong hospice users (sample size 105). Most participants were at their middle age (49-year-old on average), female (72%), with no religious affiliation (58%). Bayesian Structural Equation Modeling (BSEM) analysis was conducted on the longitudinal dataset. The BSEM findings show that hope at the first month of bereavement negatively predicts both CG and anxiety symptoms at the seventh month but not for depressive symptoms. Age and gender are controlled in the model. The overall model fit is good. The current study findings suggest assessing hope at the first month of bereavement. Hope at the first month after the loss is identified as an excellent predictor for complicated grief and anxiety symptoms at the seventh month. The result from this sample is clear, so it encourages cross-cultural research on replicated modeling and development of further clinical application. Particularly, practical consideration for early intervention to increase the level of hope has the potential to reduce the psychological symptoms and thus to improve the bereaved persons’ wellbeing in the long run.

Keywords: anxiety, complicated grief, depressive symptoms, hope, structural equational modeling

Procedia PDF Downloads 187
4858 Medical Nutritional Therapy in Human Immunodeficiency Virus Infection with Tuberculosis and Severe Malnutrition: A Case Report

Authors: Lista Andriyati, Nurpudji A Taslim

Abstract:

The human immunodeficiency virus (HIV) patients have potential nutritional and metabolic problems. HIV is a virus that attacks cells T helper and impairs the function of immune cells. Infected individuals gradually become immunodeficient, results in increased susceptibility to a wide range of infections such as tuberculosis (TB). Malnutrition has destructive effects on the immune system and host defense mechanisms. Effective and proper nutritional therapies are important to improve medical outcomes and quality of life, which is associated with functional improvement. A case of 38-years old man admitted to hospital with loss of consciousness and was diagnosed HIV infection and relapse lung TB with severe malnutrition, fever, oral candidiasis, anemia (6.3 g/dL), severe hypoalbuminemia (1.9 g/dL), severe hypokalemia (2.2 mmol/L), immune depletion (1085 /µL) and elevated liver enzyme (ALT 1198/AST 375 U/L). Nutritional intervention by giving 2300 kcal of energy, protein 2 g/IBW/day, carbohydrate 350 g, fat 104 g through enteral and parenteral nutrition. Supplementations administered are zinc, vitamin A, vitamin B1, vitamin B6, vitamin B12, vitamin C, vitamin D, and snakehead fish extract high content of protein albumin (Pujimin®). After 46 days, there are clinical and metabolic improvement in Hb (6.3 to 11.2 g/dL), potassium (2.2 to 3.4 mmol/L), albumin (1.9 to 2.3 g/dL), ALT 1198 to 47/AST 375 to 68 U/L) and improved awareness. In conclusion, nutritional therapy in HIV infection with adequate macronutrients and micronutrients fulfillment and immunonutrition is very important to avoid cachexia and to improve nutritional status and immune disfunction.

Keywords: HIV, hypoalbuminemia, malnutrition, tuberculosis

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4857 Solar Powered Front Wheel Drive (FWD) Electric Trike: An Innovation

Authors: Michael C. Barbecho, Romeo B. Morcilla

Abstract:

This study focused on the development of a solar powered front wheel drive electric trike for personal use and short distance travel, utilizing solar power and a variable speed transmission to adapt in places where varying road grades and unavailability of plug-in charging stations are of great problems. The actual performance of the vehicle was measured in terms of duration of charging using solar power, distance travel and battery power duration, top speed developed at full power, and load capacity. This project followed the research and development process which involved planning, designing, construction, and testing. Solar charging tests revealed that the vehicle requires 6 to 8 hours sunlight exposure to fully charge the batteries. At full charge, the vehicle can travel 35 km utilizing battery power down to 42%. Vehicle showed top speed of 25 kph at 0 to 3% road grade carrying a maximum load of 122 kg. The maximum climbing grade was 23% with the vehicle carrying a maximum load of 122 kg. Technically the project was feasible and can be a potential model for possible conversion of traditional Philippine made “pedicabs” and gasoline engine powered tricycle into modern electric vehicles. Moreover, it has several technical features and advantages over a commercialized electric vehicle such as the use solar charging system and variable speed power transmission and front drive power train for adaptability in any road gradient.

Keywords: electric vehicle, solar vehicles, front drive, solar, solar power

Procedia PDF Downloads 553
4856 Feasibilities for Recovering of Precious Metals from Printed Circuit Board Waste

Authors: Simona Ziukaite, Remigijus Ivanauskas, Gintaras Denafas

Abstract:

Market development of electrical and electronic equipment and a short life cycle is driven by the increasing waste streams. Gold Au, copper Cu, silver Ag and palladium Pd can be found on printed circuit board. These metals make up the largest value of printed circuit board. Therefore, the printed circuit boards scrap is valuable as potential raw material for precious metals recovery. A comparison of Cu, Au, Ag, Pd recovery from waste printed circuit techniques was selected metals leaching of chemical reagents. The study was conducted using the selected multistage technique for Au, Cu, Ag, Pd recovery of printed circuit board. In the first and second metals leaching stages, as the elution reagent, 2M H2SO4 and H2O2 (35%) was used. In the third stage, leaching of precious metals used solution of 20 g/l of thiourea and 6 g/l of Fe2 (SO4)3. Verify the efficiency of the method was carried out the metals leaching test with aqua regia. Based on the experimental study, the leaching efficiency, using the preferred methodology, 60 % of Au and 85,5 % of Cu dissolution was achieved. Metals leaching efficiency after waste mechanical crushing and thermal treatment have been increased by 1,7 times (40 %) for copper, 1,6 times (37 %) for gold and 1,8 times (44 %) for silver. It was noticed that, the Au amount in old (> 20 years) waste is 17 times more, Cu amount - 4 times more, and Ag - 2 times more than in the new (< 1 years) waste. Palladium in the new printed circuit board waste has not been found, however, it was established that from 1 t of old printed circuit board waste can be recovered 1,064 g of Pd (leaching with aqua regia). It was found that from 1 t of old printed circuit board waste can be recovered 1,064 g of Ag. Precious metals recovery in Lithuania was estimated in this study. Given the amounts of generated printed circuit board waste, the limits for recovery of precious metals were identified.

Keywords: leaching efficiency, limits for recovery, precious metals recovery, printed circuit board waste

Procedia PDF Downloads 378
4855 A Human Centered Design of an Exoskeleton Using Multibody Simulation

Authors: Sebastian Kölbl, Thomas Reitmaier, Mathias Hartmann

Abstract:

Trial and error approaches to adapt wearable support structures to human physiology are time consuming and elaborate. However, during preliminary design, the focus lies on understanding the interaction between exoskeleton and the human body in terms of forces and moments, namely body mechanics. For the study at hand, a multi-body simulation approach has been enhanced to evaluate actual forces and moments in a human dummy model with and without a digital mock-up of an active exoskeleton. Therefore, different motion data have been gathered and processed to perform a musculosceletal analysis. The motion data are ground reaction forces, electromyography data (EMG) and human motion data recorded with a marker-based motion capture system. Based on the experimental data, the response of the human dummy model has been calibrated. Subsequently, the scalable human dummy model, in conjunction with the motion data, is connected with the exoskeleton structure. The results of the human-machine interaction (HMI) simulation platform are in particular resulting contact forces and human joint forces to compare with admissible values with regard to the human physiology. Furthermore, it provides feedback for the sizing of the exoskeleton structure in terms of resulting interface forces (stress justification) and the effect of its compliance. A stepwise approach for the setup and validation of the modeling strategy is presented and the potential for a more time and cost-effective development of wearable support structures is outlined.

Keywords: assistive devices, ergonomic design, inverse dynamics, inverse kinematics, multibody simulation

Procedia PDF Downloads 149