Search results for: weed control efficiency

Authors: E. Obreque-Slier, F. Orellana-Rodríguez, R. López-Solís

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Phenolic compounds are secondary metabolites present in some foods, such as wine. Polyphenols comprise two main groups: flavonoids (anthocyanins, flavanols, and flavonols) and non-flavonoids (stilbenes and phenolic acids). Phenolic acids are low molecular weight non flavonoid compounds that are usually grouped into benzoic (gallic, vanillinic and protocatechuic acids) and cinnamic acids (ferulic, p-coumaric and caffeic acids). Likewise, tannic acid is an important polyphenol constituted mainly by gallic acid. Phenolic compounds are responsible for important properties in foods and drinks, such as color, aroma, bitterness, and astringency. Astringency is a drying, roughing, and sometimes puckering sensation that is experienced on the various oral surfaces during or immediately after tasting foods. Astringency perception has been associated with interactions between flavanols present in some foods and salivary proteins. Despite the quantitative relevance of phenolic acids in food and beverages, there is no information about its effect on salivary proteins and consequently on the sensation of astringency. The objective of this study was assessed the interaction of several phenolic acids (gallic, vanillinic, protocatechuic, ferulic, p-coumaric and caffeic acids) with saliva. Tannic acid was used as control. Thus, solutions of each phenolic acids (5 mg/mL) were mixed with human saliva (1:1 v/v). After incubation for 5 min at room temperature, 15-μL aliquots of the mixtures were dotted on a cellulose membrane and allowed to diffuse. The dry membrane was fixed in 50 g/L trichloroacetic acid, rinsed in 800 mL/L ethanol and stained for protein with Coomassie blue for 20 min, destained with several rinses of 73 g/L acetic acid and dried under a heat lamp. Both diffusion area and stain intensity of the protein spots were semiqualitative estimates for protein-tannin interaction (diffusion test). The rest of the whole saliva-phenol solution mixtures of the diffusion assay were centrifuged and fifteen-μL aliquots of each supernatant were dotted on a cellulose membrane, allowed to diffuse and processed for protein staining, as indicated above. In this latter assay, reduced protein staining was taken as indicative of protein precipitation (precipitation test). The diffusion of the salivary protein was restricted by the presence of each phenolic acids (anti-diffusive effect), while tannic acid did not alter diffusion of the salivary protein. By contrast, phenolic acids did not provoke precipitation of the salivary protein, while tannic acid produced precipitation of salivary proteins. In addition, binary mixtures (mixtures of two components) of various phenolic acids with gallic acid provoked a restriction of saliva. Similar effect was observed by the corresponding individual phenolic acids. Contrary, binary mixtures of phenolic acid with tannic acid, as well tannic acid alone, did not affect the diffusion of the saliva but they provoked an evident precipitation. In summary, phenolic acids showed a relevant interaction with the salivary proteins, thus suggesting that these wine compounds can also contribute to the sensation of astringency.

Keywords: astringency, polyphenols, tannins, tannin-protein interaction

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Authors: Brady Manescau, Ilyas Sellami, Khaled Chetehouna, Charles De Izarra, Rachid Nait-Said, Fati Zidani

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During a fire in an oil and gas refinery, several thermal accidents can occur and cause serious damage to people and environment. Among these accidents, the BLEVE (Boiling Liquid Expanding Vapor Explosion) is most observed and remains a major concern for risk decision-makers. It corresponds to a violent vaporization of explosive nature following the rupture of a vessel containing a liquid at a temperature significantly higher than its normal boiling point at atmospheric pressure. Their effects on the environment generally appear in three ways: blast overpressure, radiation from the fireball if the liquid involved is flammable and fragment hazards. In order to estimate the potential damage that would be caused by such an explosion, risk decision-makers often use quantitative risk analysis (QRA). This analysis is a rigorous and advanced approach that requires a reliable data in order to obtain a good estimate and control of risks. However, in most cases, the data used in QRA are obtained from the empirical correlations. These empirical correlations generally overestimate BLEVE effects because they are based on simplifications and do not take into account real parameters like the geometry effect. Considering that these risk analyses are based on an assessment of BLEVE effects on human life and plant equipment, more precise and reliable data should be provided. From this point of view, the CFD modeling of BLEVE effects appears as a solution to the empirical law limitations. In this context, the main objective is to develop a numerical tool in order to predict BLEVE thermal effects using the CFD code FDS version 6. Simulations are carried out with a mesh size of 1 m. The fireball source is modeled as a vertical release of hot fuel in a short time. The modeling of fireball dynamics is based on a single step combustion using an EDC model coupled with the default LES turbulence model. Fireball characteristics (diameter, height, heat flux and lifetime) issued from the large scale BAM experiment are used to demonstrate the ability of FDS to simulate the various steps of the BLEVE phenomenon from ignition up to total burnout. The influence of release parameters such as the injection rate and the radiative fraction on the fireball heat flux is also presented. Predictions are very encouraging and show good agreement in comparison with BAM experiment data. In addition, a numerical study is carried out on an operational propane accumulator in an Algerian gas processing plant of SONATRACH company located in the Hassi R’Mel Gas Field (the largest gas field in Algeria).

Keywords: BLEVE effects, CFD, FDS, fireball, LES, QRA

Procedia PDF Downloads 162

Authors: Shiamaa Eltantawy, Gihan Sobhy, Alif Alaam

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Wilson disease, or hepatolenticular degeneration, is an autosomal recessive disease that results in excess copper buildup in the body. It primarily affects the liver and basal ganglia of the brain, but it can affect other organ systems. Musculoskeletal abnormalities, including premature osteoarthritis, skeletal deformity, and pathological bone fractures, can occasionally be found in WD patients with a hepatic or neurologic type. The aim was to assess the prevalence of osteoporosis and osteopenia in Wilson’s disease patients. This case-control study was conducted on ninety children recruited from the inpatient ward and outpatient clinic of the Paediatric Hepatology, Gastroenterology, and Nutrition department of the National Liver Institute at Menofia University, aged from 1 to 18 years. Males were 49, and females were 41. Children were divided into three groups: (Group I) consisted of thirty patients with WD; (Group II) consisted of thirty patients with chronic liver disease other than WD; (Group III) consisted of thirty age- and sex-matched healthy The exclusion criteria were patients with hyperparathyroidism, hyperthyroidism, renal failure, Cushing's syndrome, and patients on certain drugs such as chemotherapy, anticonvulsants, or steroids. All patients were subjected to the following: 1- Full history-taking and clinical examination. 2-Laboratory investigations: (FBC,ALT,AST,serum albumin, total protein, total serum bilirubin,direct bilirubin,alkaline phosphatase, prothrombin time, serum critine,parathyroid hormone, serum calcium, serum phosphrus). 3-Bone mineral density (BMD, gm/cm2) values were measured by dual-energy X-ray absorptiometry (DEXA). The results revealed that there was a highly statistically significant difference between the three groups regarding the DEXA scan, and there was no statistically significant difference between groups I and II, but the WD group had the lowest bone mineral density. The WD group had a large number of cases of osteopenia and osteoporosis, but there was no statistically significant difference with the group II mean, while a high statistically significant difference was found when compared to group III. In the WD group, there were 20 patients with osteopenia, 4 patients with osteoporosis, and 6 patients who were normal. The percentages were 66.7%, 13.3%, and 20%, respectively. Therefore, the largest number of cases in the WD group had osteopenia. There was no statistically significant difference found between WD patients on different treatment regimens regarding DEXA scan results (Z-Score). There was no statistically significant difference found between patients in the WD group (normal, osteopenic, or osteoporotic) regarding phosphorus (mg/dL), but there was a highly statistically significant difference found between them regarding ionised Ca (mmol/L). Therefore, there was a decrease in bone mineral density when the Ca level was decreased. In summary, Wilson disease is associated with bone demineralization. The largest number of cases in the WD group in our study had osteopenia (66.7%). Different treatment regimens (zinc monotherapy, Artamin, and zinc) as well as different laboratory parameters have no effect on bone mineralization in WD cases. Decreased ionised Ca is associated with low BMD in WD patients. Children with WD should be investigated for BMD.

Keywords: wilson disease, Bone mineral density, liver disease, osteoporosis

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Authors: Alinka Molnár-Tóth, Tímea Tánczos, Regina Barna, Katalin Jakab, Péter Klivényi

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Supported by neuroscientific findings, the so-called Hub-and-Spoke model of the human semantic system is based on two subcomponents of semantic cognition, namely the semantic control process and semantic representation. Our semantic knowledge is multimodal in nature, as the knowledge system stored in relation to a conception is extensive and broad, while different aspects of the conception may be relevant depending on the purpose. The motivation of our research is to develop a new diagnostic measurement procedure based on the preservation of semantic representation, which is appropriate to the specificities of the Hungarian language and which can be used to compare the non-verbal semantic knowledge of healthy and aphasic persons. The development of the test will broaden the Hungarian clinical diagnostic toolkit, which will allow for more specific therapy planning. The sample of healthy persons (n=480) was determined by the last census data for the representativeness of the sample. Based on the concept of the Pyramids and Palm Tree Test, and according to the characteristics of the Hungarian language, we have elaborated a test based on different types of semantic information, in which the subjects are presented with three pictures: they have to choose the one that best fits the target word above from the two lower options, based on the semantic relation defined. We have measured 5 types of semantic knowledge representations: associative relations, taxonomy, motional representations, concrete as well as abstract verbs. As the first step in our data analysis, we examined the normal distribution of our results, and since it was not normally distributed (p < 0.05), we used nonparametric statistics further into the analysis. Using descriptive statistics, we could determine the frequency of the correct and incorrect responses, and with this knowledge, we could later adjust and remove the items of questionable reliability. The reliability was tested using Cronbach’s α, and it can be safely said that all the results were in an acceptable range of reliability (α = 0.6-0.8). We then tested for the potential gender differences using the Mann Whitney-U test, however, we found no difference between the two (p < 0.05). Likewise, we didn’t see that the age had any effect on the results using one-way ANOVA (p < 0.05), however, the level of education did influence the results (p > 0.05). The relationships between the subtests were observed by the nonparametric Spearman’s rho correlation matrix, showing statistically significant correlation between the subtests (p > 0.05), signifying a linear relationship between the measured semantic functions. A margin of error of 5% was used in all cases. The research will contribute to the expansion of the clinical diagnostic toolkit and will be relevant for the individualised therapeutic design of treatment procedures. The use of a non-verbal test procedure will allow an early assessment of the most severe language conditions, which is a priority in the differential diagnosis. The measurement of reaction time is expected to advance prodrome research, as the tests can be easily conducted in the subclinical phase.

Keywords: communication disorders, diagnostic toolkit, neurorehabilitation, semantic knowlegde

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Authors: Ch. Sridevi, A. Chalapathi Rao, P. Srinivasulu

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The location accuracy of data products is a critical parameter in assessing the geometric performance of satellite sensors. This study focuses on reliability analysis of onboard sensors to evaluate their performance in terms of location accuracy performance over time. The analysis utilizes field failure data and employs the weibull distribution to determine the reliability and in turn to understand the improvements or degradations over a period of time. The analysis begins by scrutinizing the location accuracy error which is the root mean square (RMS) error of differences between ground control point coordinates observed on the product and the map and identifying the failure data with reference to time. A significant challenge in this study is to thoroughly analyze the possibility of an infant mortality phase in the data. To address this, the Weibull distribution is utilized to determine if the data exhibits an infant stage or if it has transitioned into the operational phase. The shape parameter beta plays a crucial role in identifying this stage. Additionally, determining the exact start of the operational phase and the end of the infant stage poses another challenge as it is crucial to eliminate residual infant mortality or wear-out from the model, as it can significantly increase the total failure rate. To address this, an approach utilizing the well-established statistical Laplace test is applied to infer the behavior of sensors and to accurately ascertain the duration of different phases in the lifetime and the time required for stabilization. This approach also helps in understanding if the bathtub curve model, which accounts for the different phases in the lifetime of a product, is appropriate for the data and whether the thresholds for the infant period and wear-out phase are accurately estimated by validating the data in individual phases with Weibull distribution curve fitting analysis. Once the operational phase is determined, reliability is assessed using Weibull analysis. This analysis not only provides insights into the reliability of individual sensors with regards to location accuracy over the required period of time, but also establishes a model that can be applied to automate similar analyses for various sensors and parameters using field failure data. Furthermore, the identification of the best-performing sensor through this analysis serves as a benchmark for future missions and designs, ensuring continuous improvement in sensor performance and reliability. Overall, this study provides a methodology to accurately determine the duration of different phases in the life data of individual sensors. It enables an assessment of the time required for stabilization and provides insights into the reliability during the operational phase and the commencement of the wear-out phase. By employing this methodology, designers can make informed decisions regarding sensor performance with regards to location accuracy, contributing to enhanced accuracy in satellite-based applications.

Keywords: bathtub curve, geometric performance, Laplace test, location accuracy, reliability analysis, Weibull analysis

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Authors: Ilana Singer, Anastasia Lučić, Julie Leclerc

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Introduction: Tics, characterized by repetitive, sudden, non-voluntary motor movements or vocalizations, are prevalent in chronic tic disorder (CT) and Tourette Syndrome (TS). These neurodevelopmental disorders often coexist with various psychiatric conditions, leading to challenges and reduced quality of life. While medication in conjunction with behavioral interventions, such as Habit Reversal Training (HRT), Exposure Response Prevention (ERP), and Comprehensive Behavioral Intervention for Tics (CBIT), has shown efficacy, a significant proportion of patients experience persistent tics. Thus, innovative treatment approaches are necessary to improve therapeutic outcomes, such as mindfulness-based approaches. Nonetheless, the effectiveness of mindfulness-based interventions in the context of CT and TS remains understudied. Objective: The objective of this scoping review is to provide an overview of the current state of research on mindfulness-based interventions for CT and TS, identify knowledge and evidence gaps, discuss the effectiveness of mindfulness-based interventions with other treatment options, and discuss implications for clinical practice and policy development. Method: Using guidelines from Peters (2020) and the PRISMA-ScR, a scoping review was conducted. Multiple electronic databases were searched from inception until June 2023, including MEDLINE, EMBASE, PsychInfo, Global Health, PubMed, Web of Science, and Érudit. Inclusion criteria were applied to select relevant studies, and data extraction was independently performed by two reviewers. Results: Five papers were included in the study. Firstly, we found that mindfulness interventions were found to be effective in reducing anxiety and depression while enhancing overall well-being in individuals with tics. Furthermore, the review highlighted the potential role of mindfulness in enhancing functional connectivity within the Default Mode Network (DMN) as a compensatory function in TS patients. This suggests that mindfulness interventions may complement and support traditional therapeutic approaches, particularly HRT, by positively influencing brain networks associated with tic regulation and control. Conclusion: This scoping review contributes to the understanding of the effectiveness of mindfulness-based interventions in managing CT and TS. By identifying research gaps, this review can guide future investigations and interventions to improve outcomes for individuals with CT or TS. Overall, these findings emphasize the potential benefits of incorporating mindfulness-based interventions as a smaller subset within comprehensive treatment strategies. However, it is essential to acknowledge the limitations of this scoping review, such as the exclusion of a pre-established protocol and the limited number of studies available for inclusion. Further research and clinical exploration are necessary to better understand the specific mechanisms and optimal integration of mindfulness-based interventions with existing behavioral interventions for this population.

Keywords: scoping reviews, Tourette Syndrome, tics, mindfulness-based, therapy, intervention

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Authors: Getahun Lemma

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Introduction Guinea Worm Disease (GWD), also known as dracunculiasisis, is one of the oldest diseases in the history of mankind. Dracunculiasis is caused by a parasitic nematode, Dracunculus medinensis. Infection is acquired by drinking contaminated water with copepods containing infective Guinea Worm (GW) larvae). Almost one year after the infection, the worm usually emerges out through the skin on a lower, causing severe pain and disabilities. Although there is no effective drug or vaccine against the disease, the chain of transmission can be effectively prevented with simple and cost effective public health measures. Death due to dracunculiasis is very rare. However, it results in a wide range of physical, social and economic sequels. The disease is usually common in the rural, remote places of Sub-Saharan African countries among the marginalized societies. Currently, GWD is one of the neglected tropical diseases, which is on the verge of eradication. The global Guinea Worm Eradication Program (GWEP) was started in 1980. Since then, the program has achieved a tremendous success in reducing the global burden and number of GW case from 3.5 million to only 28 human cases at the end of 2018. However, it has recently been shown that not only humans can become infected, with a total of 1,105 animal infections have been reported at the end of 2018. Therefore, the objective of this study was to identify the existing challenges in the last mile of the GWEP in order To inform Policy makers and stakeholders on potential measures to finally achieve eradication. Method Systematic literature review on articles published from January 1, 2000 until May 30, 2019. Papers listed in Cochrane Library, Google Scholar, ProQuest PubMed and Web of Science databases were searched and reviewed. Results Twenty-five articles met inclusion criteria of the study and were selected for analysis. Hence, relevant data were extracted, grouped and descriptively analyzed. Results showed the main challenges complicating the last mile of global GWEP: 1. Unusual mode of transmission; 2. Rising animal Guinea Worm infection; 3. Suboptimal surveillance; 4. Insecurity; 5. Inaccessibility; 6. Inadequate safe water points; 7. Migration; 8. Poor case containment measures, 9. Ecological changes; and 10. New geographic foci of the disease. Conclusion This systematic review identified that most of the current challenges in the GWEP have been present since the start of the campaign. However, the recent change in epidemiological patterns and nature of GWD in the last remaining endemic countries illustrates a new twist in the global GWEP. Considering the complex nature of the current challenges, there seems to be a need for a more coordinated and multidisciplinary approach of GWD prevention and control measures in the last mile of the campaign. These new strategies would help to make history by eradicating dracunculiasis as the first ever parasitic disease.

Keywords: dracunculiasis, eradication program, guinea worm, last mile

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Authors: Willian C. De Brito, Hernan D. C. Munoz, Erlan V. C. Carvalho, Helder L. C. De Oliveira

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In order to improve commute time for small distance trips and relieve large cities traffic, a new transport category has been the subject of research and new designs worldwide. The air taxi travel market promises to change the way people live and commute by using the concept of vehicles with the ability to take-off and land vertically and to provide passenger’s transport equivalent to a car, with mobility within large cities and between cities. Today’s civil air transport remains costly and accounts for 2% of the man-made CO₂ emissions. Taking advantage of this scenario, many companies have developed their own Vertical Take Off and Landing (VTOL) design, seeking to meet comfort, safety, low cost and flight time requirements in a sustainable way. Thus, the use of green power supplies, especially batteries, and fully electric power plants is the most common choice for these arising aircrafts. However, it is still a challenge finding a feasible way to handle with the use of batteries rather than conventional petroleum-based fuels. The batteries are heavy and have an energy density still below from those of gasoline, diesel or kerosene. Therefore, despite all the clear advantages, all electric aircrafts (AEA) still have low flight autonomy and high operational cost, since the batteries must be recharged or replaced. In this sense, this paper addresses a way to optimize the energy consumption in a typical mission of an aerial taxi aircraft. The approach and landing procedure was chosen to be the subject of an optimization genetic algorithm, while final programming can be adapted for take-off and flight level changes as well. A real tilt rotor aircraft with fully electric power plant data was used to fit the derived dynamic equations of motion. Although a tilt rotor design is used as a proof of concept, it is possible to change the optimization to be applied for other design concepts, even those with independent motors for hover and cruise flight phases. For a given trajectory, the best set of control variables are calculated to provide the time history response for aircraft´s attitude, rotors RPM and thrust direction (or vertical and horizontal thrust, for independent motors designs) that, if followed, results in the minimum electric power consumption through that landing path. Safety, comfort and design constraints are assumed to give representativeness to the solution. Results are highly dependent on these constraints. For the tested cases, performance improvement ranged from 5 to 10% changing initial airspeed, altitude, flight path angle, and attitude.

Keywords: air taxi travel, all electric aircraft, batteries, energy consumption, genetic algorithm, landing performance, optimization, performance improvement, tilt rotor, VTOL design

Procedia PDF Downloads 90

Authors: E. Akdur Öztürk, F. İrvasa Bilgiç, A. Ludovisi , O. Gülbahar, D. Dirim Erdoğan, M. Korkmaz, M. Á. Gómez Morales

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Anisakidosis is a zoonotic human fish-borne parasitic disease caused by accidental ingestion of anisakid third-stage larvae (L3) of members of the Anisakidae family present in infected marine fish or cephalopods. Infection with anisakid larvae can lead to gastric, intestinal, extra-gastrointestinal and gastroallergic forms of the disease. Anisakid parasites have been reported in almost all seas, particularly in the Mediterranean Sea. There is a remarkably high level of risk exposure to these zoonotic parasites as they are present in economically and ecologically important fish of Europe. Anisakid L3 larvae have been also detected in several fish species from the Aegean Sea. Turkey is a peninsular country surrounded by Black, Aegean and the Mediterranean Sea. In this country, fishing habit and fishery product consumption are highly common. In recent years, there was also an increase in the consumption of raw fish due to the increasing interest in the cuisine of the Far East countries. In different regions of Turkey, A. simplex (inMerluccius Merluccius Scomber japonicus, Trachurus mediterraneus, Sardina pilchardus, Engraulis encrasicolus, etc.), Anisakis spp., Contraceucum spp., Pseudoterronova spp. and, C. aduncum were identified as well. Although it is accepted both the presence of anisakid parasites in fish and fishery products in Turkey and the presence of Turkish people with allergic manifestations after fish consumption, there are no reports of human anisakiasis in this country. Given the high prevalence of anisakid parasites in the country, the absence of reports is likely not due to the absence of clinical cases rather to the unavailability of diagnostic tools and the low awareness of the presence of this infection. The aim of the study was to set up an IgE-Western Blot (WB) based test to detect the anisakidosis sensitization among Turkish people with a history of allergic manifestation related to fish consumption. To this end, crude worm antigens (CWA) and allergen enriched fraction (50-66% ) were prepared from L3 of A. simplex (s.l.) collected from Lepidopus caudatus fished in the Mediterranean Sea. These proteins were electrophoretically separated and transferred into the nitrocellulose membranes. By WB, specific proteins recognized by positive control serum samples from sensitized patients were visualized on nitrocellulose membranes by a colorimetric reaction. The CWA and 50–66% fraction showed specific bands, mainly due to Ani s 1 (20-22 kD) and Ani s 4 (9-10 kD). So far, a total of 7 serum samples from people with allergic manifestation and positive skin prick test (SPT) after fish consumption, have been tested and all of them resulted negative by WB, indicating the lack of sensitization to anisakids. This preliminary study allowed to set up a specific test and evidence the lack of correlation between both tests, SPT and WB. However, the sample size should be increased to estimate the anisakidosis burden in Turkish people.

Keywords: anisakidosis, fish parasite, serodiagnosis, Turkey

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Authors: Ryan B. Simpson, Margaret A. Waskow, Aishwarya Venkat, Elena N. Naumova

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The Centers for Disease Control and Prevention (CDC) estimate that 31 known foodborne pathogens cause 9.4 million cases of these illnesses annually in US. Over 90% of these illnesses are associated with exposure to Campylobacter, Cryptosporidium, Cyclospora, Listeria, Salmonella, Shigella, Shiga-Toxin Producing E.Coli (STEC), Vibrio, and Yersinia. Contaminated products contain parasites typically causing an intestinal illness manifested by diarrhea, stomach cramping, nausea, weight loss, fatigue and may result in deaths in fragile populations. Since 1998, the National Outbreak Reporting System (NORS) has allowed for routine collection of suspected and laboratory-confirmed cases of food poisoning. While retrospective analyses have revealed common pathogen-specific seasonal patterns, little is known concerning the stability of those patterns over time and whether they can be used for preventative forecasting. The objective of this study is to construct a calendar of foodborne outbreaks of nine infections based on the peak timing of outbreak incidence in the US from 1996 to 2017. Reported cases were abstracted from FoodNet for Salmonella (135115), Campylobacter (121099), Shigella (48520), Cryptosporidium (21701), STEC (18022), Yersinia (3602), Vibrio (3000), Listeria (2543), and Cyclospora (758). Monthly counts were compiled for each agent, seasonal peak timing and peak intensity were estimated, and the stability of seasonal peaks and synchronization of infections was examined. Negative Binomial harmonic regression models with the delta-method were applied to derive confidence intervals for the peak timing for each year and overall study period estimates. Preliminary results indicate that five infections continue to lead as major causes of outbreaks, exhibiting steady upward trends with annual increases in cases ranging from 2.71% (95%CI: [2.38, 3.05]) in Campylobacter, 4.78% (95%CI: [4.14, 5.41]) in Salmonella, 7.09% (95%CI: [6.38, 7.82]) in E.Coli, 7.71% (95%CI: [6.94, 8.49]) in Cryptosporidium, and 8.67% (95%CI: [7.55, 9.80]) in Vibrio. Strong synchronization of summer outbreaks were observed, caused by Campylobacter, Vibrio, E.Coli and Salmonella, peaking at 7.57 ± 0.33, 7.84 ± 0.47, 7.85 ± 0.37, and 7.82 ± 0.14 calendar months, respectively, with the serial cross-correlation ranging 0.81-0.88 (p < 0.001). Over 21 years, Listeria and Cryptosporidium peaks (8.43 ± 0.77 and 8.52 ± 0.45 months, respectively) have a tendency to arrive 1-2 weeks earlier, while Vibrio peaks (7.8 ± 0.47) delay by 2-3 weeks. These findings will be incorporated in the forecast models to predict common paths of the spread, long-term trends, and the synchronization of outbreaks across etiological agents. The predictive modeling of foodborne outbreaks should consider long-term changes in seasonal timing, spatiotemporal trends, and sources of contamination.

Keywords: foodborne outbreak, national outbreak reporting system, predictive modeling, seasonality

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Authors: Manel Hammami, Gabriele Grandi

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In recent years, multilevel inverters have become more attractive for single-phase photovoltaic (PV) systems, due to their known advantages over conventional H-bridge pulse width-modulated (PWM) inverters. They offer improved output waveforms, smaller filter size, lower total harmonic distortion (THD), higher output voltages and others. The most common multilevel converter topologies, presented in literature, are the neutral-point-clamped (NPC), flying capacitor (FC) and Cascaded H-Bridge (CHB) converters. In both NPC and FC configurations, the number of components drastically increases with the number of levels what leads to complexity of the control strategy, high volume, and cost. Whereas, increasing the number of levels in case of the cascaded H-bridge configuration is a flexible solution. However, it needs isolated power sources for each stage, and it can be applied to PV systems only in case of PV sub-fields. In order to improve the ratio between the number of output voltage levels and the number of components, several hybrids and asymmetric topologies of multilevel inverters have been proposed in the literature such as the FC asymmetric H-bridge (FCAH) and the NPC asymmetric H-bridge (NPCAH) topologies. Another asymmetric multilevel inverter configuration that could have interesting applications is the cascaded asymmetric H-bridge (CAH), which is based on a modular half-bridge (two switches and one capacitor, also called level doubling network, LDN) cascaded to a full H-bridge in order to double the output voltage level. This solution has the same number of switches as the above mentioned AH configurations (i.e., six), and just one capacitor (as the FCAH). CAH is becoming popular, due to its simple, modular and reliable structure, and it can be considered as a retrofit which can be added in series to an existing H-Bridge configuration in order to double the output voltage levels. In this paper, an original and effective method for the analysis of the DC-link voltage ripple is given for single-phase asymmetric H-bridge multilevel inverters based on level doubling network (LDN). Different possible configurations of the asymmetric H-Bridge multilevel inverters have been considered and the analysis of input voltage and current are analytically determined and numerically verified by Matlab/Simulink for the case of cascaded asymmetric H-bridge multilevel inverters. A comparison between FCAH and the CAH configurations is done on the basis of the analysis of the DC and voltage ripple for the DC source (i.e., the PV system). The peak-to-peak DC and voltage ripple amplitudes are analytically calculated over the fundamental period as a function of the modulation index. On the basis of the maximum peak-to-peak values of low frequency and switching ripple voltage components, the DC capacitors can be designed. Reference is made to unity output power factor, as in case of most of the grid-connected PV generation systems. Simulation results will be presented in the full paper in order to prove the effectiveness of the proposed developments in all the operating conditions.

Keywords: asymmetric inverters, dc-link voltage, level doubling network, single-phase multilevel inverter

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Authors: K. Verma, v. S. Moholkar

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In developed countries, water pollution caused by industrial discharge has emerged as a significant environmental concern over the past decades. However, despite ongoing efforts, a fully effective and sustainable remediation strategy has yet to be identified. This paper describes how enzymatic and sonochemical treatments have demonstrated great promise in degrading bio-refractory pollutants. Mainly, a compelling area of interest lies in the combined technique of sono-enzymatic treatment, which has exhibited a synergistic enhancement effect surpassing that of the individual techniques. This study employed the covalent attachment method to immobilize Laccase from Trametes versicolor onto amino-functionalized magnetic Fe₃O₄ nanoparticles. To comprehensively characterize the synthesized free nanoparticles and the laccase-immobilized nanoparticles, various techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), vibrating sample magnetometer (VSM), and surface area through Brunauer-Emmett-Teller (BET) were employed. The size of immobilized Fe₃O₄@Laccase was found to be 60 nm, and the maximum loading of laccase was found to be 24 mg/g of nanoparticle. An investigation was conducted to study the effect of various process parameters, such as immobilized Fe₃O₄ Laccase dose, temperature, and pH, on the % Chemical oxygen demand (COD) removal as a response. The statistical design pinpointed the optimum conditions (immobilized Fe₃O₄ Laccase dose = 1.46 g/L, pH = 4.5, and temperature = 66 oC), resulting in a remarkable 65.58% COD removal within 60 minutes. An even more significant improvement (90.31% COD removal) was achieved with ultrasound-assisted enzymatic reaction utilizing a 10% duty cycle. The investigation of various kinetic models for free and immobilized laccase, such as the Haldane, Yano, and Koga, and Michaelis-Menten, showed that ultrasound application impacted the kinetic parameters Vmax and Km. Specifically, Vmax values for free and immobilized laccase were found to be 0.021 mg/L min and 0.045 mg/L min, respectively, while Km values were 147.2 mg/L for free laccase and 136.46 mg/L for immobilized laccase. The lower Km and higher Vmax for immobilized laccase indicate its enhanced affinity towards the substrate, likely due to ultrasound-induced alterations in the enzyme's confirmation and increased exposure of active sites, leading to more efficient degradation. Furthermore, the toxicity and Liquid chromatography-mass spectrometry (LC-MS) analysis revealed that after the treatment process, the wastewater exhibited 70% less toxicity than before treatment, with over 25 compounds degrading by more than 75%. At last, the prepared immobilized laccase had excellent recyclability retaining 70% activity up to 6 consecutive cycles. A straightforward manufacturing strategy and outstanding performance make the recyclable magnetic immobilized Laccase (Fe₃O₄ Laccase) an up-and-coming option for various environmental applications, particularly in water pollution control and treatment.

Keywords: kinetic, laccase enzyme, sonoenzymatic, ultrasound irradiation

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Authors: Suzanne Zazycki, Bamidele Osamika, Heather Craska, Kaelyn Conaway, Reena Murphy, Stephanie Spence

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Invasive Plant Species (IPS) are an important component of effective preservation and conservation of natural lands management. IPS are non-native plants which can aggressively encroach upon native species and pose a significant threat to the ecology, public health, and social welfare of a community. The presence of IPS in U.S. nature preserves has caused economic costs, which has estimated to exceed $26 billion a year. While different methods have been identified to control IPS, few methods have been recognized for early detection of IPS. This study examined identified methods for early detection of IPS in Hueston Woods State Nature Preserve. Mixed methods research design was adopted in this four-phased study. The first phase entailed data gathering, the phase described the characteristics and qualities of IPS and the importance of early detection (ED). The second phase explored ED methods, Geographic Information Systems (GIS) and Citizen Science were discovered as ED methods for IPS. The third phase of the study involved the creation of hotspot maps to identify likely areas for IPS growth. While the fourth phase involved testing and evaluating mobile applications that can support the efforts of citizen scientists in IPS detection. Literature reviews were conducted on IPS and ED methods, and four regional experts from ODNR and Miami University were interviewed. A questionnaire was used to gather information about ED methods used across the state. The findings revealed that geospatial methods, including Unmanned Aerial Vehicles (UAVs), Multispectral Satellites (MSS), and Normalized Difference Vegetation Index (NDVI), are not feasible for early detection of IPS, as they require GIS expertise, are still an emerging technology, and are not suitable for every habitat for the ED of IPS. Therefore, Other ED methods options were explored, which include predicting areas where IPS will grow, which can be done through monitoring areas that are like the species’ native habitat. Through literature review and interviews, IPS are known to grow in frequently disturbed areas such as along trails, shorelines, and streambanks. The research team called these areas “hotspots” and created maps of these hotspots specifically for HW NP to support and narrow the efforts of citizen scientists and staff in the ED of IPS. The results further showed that utilizing citizen scientists in the ED of IPS is feasible, especially through single day events or passive monitoring challenges. The study concluded that the creation of hotspot maps to direct the efforts of citizen scientists are effective for the early detection of IPS. Several recommendations were made, among which is the creation of hotspot maps to narrow the ED efforts as citizen scientists continues to work in the preserves and utilize citizen science volunteers to identify and record emerging IPS.

Keywords: early detection, hueston woods state nature preserve, invasive plant species, hotspots

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Authors: Jayden R. Hunter, Alexander J. MacQuarrie, Samantha C. Sheridan, Richard High, Carolyn Waite

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Workplace exercise programs have been recommended to improve the musculoskeletal fitness of paramedics with the aim of reducing injury rates, and while they have shown efficacy in other occupations, they have not been delivered and evaluated in Australian paramedics to our best knowledge. This study investigated the effectiveness of a 6-month workplace exercise program (MedicFit; MF) to improve paramedic fitness with or without health coach (HC) support. A group of regional Australian paramedics (n=76; 43 male; mean ± SD 36.5 ± 9.1 years; BMI 28.0 ± 5.4 kg/m²) were randomised at the station level to either exercise with remote health coach support (MFHC; n=30), exercise without health coach support (MF; n=23), or no-exercise control (CON; n=23) groups. MFHC and MF participants received a 6-month, low-moderate intensity resistance and flexibility exercise program to be performed ƒ on station without direct supervision. Available exercise equipment included dumbbells, resistance bands, Swiss balls, medicine balls, kettlebells, BOSU balls, yoga mats, and foam rollers. MFHC and MF participants were also provided with a comprehensive exercise manual including sample exercise sessions aimed at improving musculoskeletal strength and flexibility which included exercise prescription (i.e. sets, reps, duration, load). Changes to upper-body (push-ups), lower-body (wall squat) and core (plank hold) strength and flexibility (back scratch and sit-reach tests) after the 6-month intervention were analysed using repeated measures ANOVA to compare changes between groups and over time. Upper-body (+20.6%; p < 0.01; partial eta squared = 0.34 [large effect]) and lower-body (+40.8%; p < 0.05; partial eta squared = 0.08 (moderate effect)) strength increased significantly with no interaction or group effects. Changes to core strength (+1.4%; p=0.17) and both upper-body (+19.5%; p=0.56) and lower-body (+3.3%; p=0.15) flexibility were non-significant with no interaction or group effects observed. While upper- and lower-body strength improved over the course of the intervention, providing a 6-month workplace exercise program with or without health coach support did not confer any greater strength or flexibility benefits than exercise testing alone (CON). Although exercise adherence was not measured, it is possible that participants require additional methods of support such as face-to-face exercise instruction and guidance and individually-tailored exercise programs to achieve adequate participation and improvements in musculoskeletal fitness. This presents challenges for more remote paramedic stations without regular face-to-face access to suitably qualified exercise professionals, and future research should investigate the effectiveness of other forms of exercise delivery and guidance for these paramedic officers such as remotely-facilitated digital exercise prescription and monitoring.

Keywords: workplace exercise, paramedic health, strength training, flexibility training

Procedia PDF Downloads 117

Authors: Lucie Speyer, Vincent Lecocq, Séverine Humbert, Antoine Hugon

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Mesoporous alumina is commonly used as a catalyst support for the hydrotreating of heavy petroleum cuts. The process of fabrication usually involves: the synthesis of the boehmite AlOOH precursor, a kneading-extrusion step, and a calcination in order to obtain the final alumina extrudates. Alumina is described as a complex porous medium, generally agglomerates constituted of aggregated nanocrystallites. Its porous texture directly influences the active phase deposition and mass transfer, and the catalytic properties. Then, it is easy to figure out that each step of the fabrication of the supports has a role on the building of their porous network, and has to be well understood to optimize the process. The synthesis of boehmite by precipitation of aluminum salts was extensively studied in the literature and the effect of various parameters, such as temperature or pH, are known to influence the size and shape of the crystallites and the specific surface area of the support. The calcination step, through the topotactic transition from boehmite to alumina, determines the final properties of the support and can tune the surface area, pore volume and pore diameters from those of boehmite. However, the kneading extrusion step has been subject to a very few studies. It generally consists in two steps: an acid, then a basic kneading, where the boehmite powder is introduced in a mixer and successively added with an acid and a base solution to form an extrudable paste. During the acid kneading, the induced positive charges on the hydroxyl surface groups of boehmite create an electrostatic repulsion which tends to separate the aggregates and even, following the conditions, the crystallites. The basic kneading, by reducing the surface charges, leads to a flocculation phenomenon and can control the reforming of the overall structure. The separation and reassembling of the particles constituting the boehmite paste have a quite obvious influence on the textural properties of the material. In this work, we are focused on the influence of the kneading step on the alumina catalysts supports. Starting from an industrial boehmite, extrudates are prepared using various kneading conditions. The samples are studied by nitrogen physisorption in order to analyze the evolution of the textural properties, and by synchrotron small-angle X-ray scattering (SAXS), a more original method which brings information about agglomeration and aggregation of the samples. The coupling of physisorption and SAXS enables a precise description of the samples, as same as an accurate monitoring of their evolution as a function of the kneading conditions. These ones are found to have a strong influence of the pore volume and pore size distribution of the supports. A mechanism of evolution of the texture during the kneading step is proposed and could be attractive in order to optimize the texture of the supports and then, their catalytic performances.

Keywords: alumina catalyst support, kneading, nitrogen physisorption, small-angle X-ray scattering

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Authors: Kamal Ray, Tapati Bhattacharya

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Private use of public office for private gain could be a tentative definition of corruption and most distasteful event of corruption is that it is not there, nor that it is pervasive, but it is socially acknowledged in the global economy, especially in the developing nations. We attempted to assess the interrelationship between the Corruption perception index (CPI) and the principal components of governance indicators as per World Bank like Control of Corruption (CC), rule of law (RL), regulatory quality (RQ) and government effectiveness (GE). Our empirical investigation concentrates upon the degree of reflection of governance indicators upon the CPI in order to single out the most powerful corruption-generating indicator in the selected countries. We have collected time series data on above governance indicators such as CC, RL, RQ and GE of the selected eleven countries from the year of 1996 to 2012 from World Bank data set. The countries are USA, UK, France, Germany, Greece, China, India, Japan, Thailand, Brazil, and South Africa. Corruption Perception Index (CPI) of the countries mentioned above for the period of 1996 to 2012is also collected. Graphical method of simple line diagram against the time series data on CPI is applied for quick view for the relative positions of different trend lines of different nations. The correlation coefficient is enough to assess primarily the degree and direction of association between the variables as we get the numerical data on governance indicators of the selected countries. The tool of Granger Causality Test (1969) is taken into account for investigating causal relationships between the variables, cause and effect to speak of. We do not need to verify stationary test as length of time series is short. Linear regression is taken as a tool for quantification of a change in explained variables due to change in explanatory variable in respect of governance vis a vis corruption. A bilateral positive causal link between CPI and CC is noticed in UK, index-value of CC increases by 1.59 units as CPI increases by one unit and CPI rises by 0.39 units as CC rises by one unit, and hence it has a multiplier effect so far as reduction in corruption is concerned in UK. GE causes strongly to the reduction of corruption in UK. In France, RQ is observed to be a most powerful indicator in reducing corruption whereas it is second most powerful indicator after GE in reducing of corruption in Japan. Governance-indicator like GE plays an important role to push down the corruption in Japan. In China and India, GE is proactive as well as influencing indicator to curb corruption. The inverse relationship between RL and CPI in Thailand indicates that ongoing machineries related to RL is not complementary to the reduction of corruption. The state machineries of CC in S. Africa are highly relevant to reduce the volume of corruption. In Greece, the variations of CPI positively influence the variations of CC and the indicator like GE is effective in controlling corruption as reflected by CPI. All the governance-indicators selected so far have failed to arrest their state level corruptions in USA, Germany and Brazil.

Keywords: corruption perception index, governance indicators, granger causality test, regression

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Authors: Tuba Denkceken, Ayse Nur Sarı, Volkan Ihsan Tore, Mahmut Denkceken

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The aim of the presented study was to develop a newly motorized spectroscopy system. Our system is composed of probe and motor parts. The probe part consists of bioimpedance and fiber optic components that include two platinum wires (each 25 micrometer in diameter) and two fiber cables (each 50 micrometers in diameter) respectively. Probe was examined on tissue phantom (polystyrene microspheres with different diameters). In the bioimpedance part of the probe current was transferred to the phantom and conductivity information was obtained. Adjacent two fiber cables were used in the fiber optic part of the system. Light was transferred to the phantom by fiber that was connected to the light source and backscattered light was collected with the other adjacent fiber for analysis. It is known that the nucleus expands and the nucleus-cytoplasm ratio increases during the cancer progression in the cell and this situation is one of the most important criteria for evaluating the tissue for pathologists. The sensitivity of the probe to particle (nucleus) size in phantom was tested during the study. Spectroscopic data obtained from our system on phantom was evaluated by multivariate statistical analysis. Thus the information about the particle size in the phantom was obtained. Bioimpedance and fiber optic experiments results which were obtained from polystyrene microspheres showed that the impedance value and the oscillation amplitude were increasing while the size of particle was enlarging. These results were compatible with the previous studies. In order to motorize the system within the motor part, three driver electronic circuits were designed primarily. In this part, supply capacitors were placed symmetrically near to the supply inputs which were used for balancing the oscillation. Female capacitors were connected to the control pin. Optic and mechanic switches were made. Drivers were structurally designed as they could command highly calibrated motors. It was considered important to keep the drivers’ dimension as small as we could (4.4x4.4x1.4 cm). Then three miniature step motors were connected to each other along with three drivers. Since spectroscopic techniques are quantitative methods, they yield more objective results than traditional ones. In the future part of this study, it is planning to get spectroscopic data that have optic and impedance information from the cell culture which is normal, low metastatic and high metastatic breast cancer. In case of getting high sensitivity in differentiated cells, it might be possible to scan large surface tissue areas in a short time with small steps. By means of motorize feature of the system, any region of the tissue will not be missed, in this manner we are going to be able to diagnose cancerous parts of the tissue meticulously. This work is supported by The Scientific and Technological Research Council of Turkey (TÜBİTAK) through 3001 project (115E662).

Keywords: motorized spectroscopy, phantom, scanning system, tissue scanning

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Authors: Olfat Mohamed Hussien Yousef

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Tamoxifen (TM) is a synthetic non-steroidal antiestrogen. It is one of the most effective drugs for treatment of estrogen-dependent cancer by binding to estrogen receptors, suppressing of epithelial proliferation and as a chemotherapeutic agent. Recently, more attention has been paid to the protective effects of natural antioxidants against toxicities induced by anti-cancer drugs involving free radical-mediated oxidative stress and tissue injury. Vitamin C is a potent antioxidant that has the ability to scavenge factors causing free radical formation in animals receiving tamoxifen. The present study aims at pinpointing the TM-induced histopathological and ultrastructural changes in the kidneys and to assess the possible chemoprotective role of vitamin C against such TM-induced microscopic changes. Thirty adult male CD-1 mice, 25-30 g in weight and 3 months old, were divided into three groups. The first group served as control. The second group received the therapeutic dose of TM at daily oral dose of 40 mg/kg body weight for 28 days. The third group received the therapeutic dose of vitamin C at a daily dose of 500 mg/kg body weight simultaneously with the therapeutic dose of TM used in group two for 28 days. Animals were sacrificed and kidney samples were obtained and processed for histological and ultrastructural examination. Histological changes induced by TM included damage of the renal corpuscles including obliteration of the subcapsular space, congestion of the glomerular blood capillaries, segmental mesangial cell proliferation with matrix expansion, capsular adhesions with the glomerular tuft especially at the urinary pole of the corpuscles. Moreover, some proximal and distal tubules suffered various degrees of degeneration in some lining cells. Haemorrhage and inflammatory cell infiltration were also observed in the intertubular spaces. Ultrastructural observations revealed damage of the parietal epithelium of Bowman’s capsule, fusion and destruction of the foot processes of podocytes and great increase of mesangial cells and mesangial matrix. The cells of the proximal convoluted tubules displayed marked destruction of the microvilli constituting the brush borders and degeneration of the mitochondria; besides, abundant lysosomes, numerous vacuoles and pyknotic nuclei were observed. The distal convoluted tubules displayed marked distruction of both the basal infolding and the mitochondria in some areas. Histological and ultrastructural results revealed that treatment of male mice with TM simultaneously with vitamin C led to apparent repair of the injured renal tissue. This might suggest that vitamin C (an antioxidant agent) can minimize the toxic effects of TM (an antiestrogen).

Keywords: tamoxifen, vitamin c, mammalian kidney, histology, ultrastructure

Procedia PDF Downloads 353

Authors: Nurgul A. Abenova, Gaukhar S. Dilmagambetova, Lazzat M. Zhamaliyeva

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Professionalism is a core competency that all medical students must achieve throughout their studies. Clinical knowledge, good communication skills and an understanding of ethics form the basis of professionalism. Patients, medical societies and accrediting organizations expect future specialists to be professionals in their field, which in turn leads to the best clinical results. Currently, there are no studies devoted to the study of medical professionalism in the Republic of Kazakhstan. As a result, medical education in the Kazakhstani system has a limited perception of the concept of professionalism compared to many Western medical schools. Thus, the primary purpose of this study is to analyze the perception of medical professionalism among residents and teachers of family medicine at the West Kazakhstan Marat Ospanov Medical University. А qualitative research method was used based on the content analysis methodology. A focus group discussion was held with 60 residents and 12 family medicine teachers to gather participants' views and experiences in the field of medical professionalism. The received information was processed using the MAXQDA-2020 software package. Respondents were selected for the study based on their age, gender, and educational level. The results of the conducted survey confirmed the respondents’ acknowledgment of the basic attributes of professionalism, such as medical knowledge and skills (more than 40% of the answers), personal and moral qualities of the doctor (more than 25% of the answers), respect for the interests of the patient (15% of the answers), the relationship between the doctor and the patient and among professionals themselves (15% of responses). Another important discovery of the survey was that residents are five times more likely to define the relationship between a doctor and a patient in a model “respect for the interests of the patient” in comparison with teachers of family medicine, who primarily reported responsibility and collegiality to be the basis for the development of professionalism and traditionally view doctor-patient relationship to be formed on the basis of paternalism defined by a high degree of control over patients. This significant difference demonstrates a rift among specialists in the field of family medicine, which causes a lot of problems. For example, nowadays, professional family doctors regularly face burnout problem due to many reasons and factors that force them to abandon their jobs. In addition to that, elements of professionalism such as reflective skills, time management and feedback collection were presented to the least extent (less than 1%) by both groups, which differs from the perception of the Western medical school and is a significant issue that needs to be solved. The qualitative nature of our study provides a detailed understanding of medical professionalism in the context of the Central Asian healthcare system, revealing many aspects that are inferior to the Western medical school counterparts and provides a solution, which is to teach the attributes and skills required for medical professionalism at all stages of medical education of family doctors.

Keywords: family medicine, family doctors, medical professionalism, medical education

Procedia PDF Downloads 118

Authors: Blanca A. Pichardo, Victor H. Lopez, Melchor Salazar, Rafael Garcia, Alberto Ruiz

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Clad pipes in comparison to plain carbon steel pipes offer the oil and gas industry high corrosion resistance, reduction in economic losses due to pipeline failures and maintenance, lower labor risk, prevent pollution and environmental damage due to hydrocarbons spills caused by deteriorated pipelines. In this context, it is paramount to establish reliable welding procedures to join bimetallic plates or pipes. Thus, the aim of this work is to study the microstructure and mechanical behavior of clad plates welded by the gas metal arc welding (GMAW) process. A clad of 316L stainless steel was deposited onto API 5L X-60 plates by overlay welding with the GMAW process. Welding parameters were, 22.5 V, 271 A, heat input 1,25 kJ/mm, shielding gas 98% Ar + 2% O₂, reverse polarity, torch displacement speed 3.6 mm/s, feed rate 120 mm/s, electrode diameter 1.2 mm and application of an electromagnetic field of 3.5 mT. The overlay welds were subjected to macro-structural and microstructural characterization. After manufacturing the clad plates, a single V groove joint was machined with a 60° bevel and 1 mm root face. GMA welding of the bimetallic plates was performed in four passes with ER316L-Si filler for the root pass and an ER70s-6 electrode for the subsequent welding passes. For joining the clad plates, an electromagnetic field was applied with 2 purposes; to improve the microstructural characteristics and to assist the stability of the electric arc during welding in order to avoid magnetic arc blow. The welds were macro and microstructurally characterized and the mechanical properties were also evaluated. Vickers microhardness (100 g load for 10 s) measurements were made across the welded joints at three levels. The first profile, at the 316L stainless steel cladding, was quite even with a value of approximately 230 HV. The second microhardness profile showed high values in the weld metal, ~400 HV, this was due to the formation of a martensitic microstructure by dilution of the first welding pass with the second. The third profile crossed the third and fourth welding passes and an average value of 240 HV was measured. In the tensile tests, yield strength was between 400 to 450 MPa with a tensile strength of ~512 MPa. In the Charpy impact tests, the results were 86 and 96 J for specimens with the notch in the face and in the root of the weld bead, respectively. The results of the mechanical properties were in the range of the API 5L X-60 base material. The overlap welding process used for cladding is not suitable for large components, however, it guarantees a metallurgical bond, unlike the most commonly used processes such as thermal expansion. For welding bimetallic plates, control of the temperature gradients is key to avoid distortions. Besides, the dissimilar nature of the bimetallic plates gives rise to the formation of a martensitic microstructure during welding.

Keywords: clad pipe, dissimilar welding, gas metal arc welding, magnetic fields

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Authors: Yuki Matsumoto, Yuma Ishimoto

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Cognitive Behavior Therapy (CBT) with children has shown effective application to various problems such as anxiety and depression. Although there are barriers to access to mental health services including lack of professional services in communities and parental concerns about stigma, school has a significant role to address children’s health problems. Schools are regarded as a suitable arena for prevention and early intervention of mental health problems. In this line, CBT can be adaptable to school education and useful to enhance students’ social and emotional skills. However, Japanese school curriculum is rigorous so as to limit available time for implementation of CBT in schools. This paper describes Brief Cognitive Behavior Therapy (BCBT) with children in a Japanese school setting. The program has been developed in order to facilitate acceptability of CBT in schools and aimed to enhance students’ skills to manage anxiety and difficult behaviors. The present research used a single arm design in which 30 students aged 9-10 years old participated. The authors provided teachers a CBT training workshop (two hours) at two primary schools in Tokyo metropolitan area and recruited participants in the research. A homeroom teacher voluntarily delivered a 6-session BCBT program (15 minutes each) in classroom periods which is called as Kaerinokai, a meeting before leaving school. Students completed a questionnaire sheet at pre- and post-periods under the supervision of the teacher. The sheet included the Spence Child Anxiety Scale (SCAS), the Depression Self-Rating Scale for Children (DSRS), and the Strengths and Difficulties Questionnaire (SDQ). The teacher was asked for feedback after the completion. Significant positive changes were found in the total and five of six sub-scales of the SCAS and the total difficulty scale of the SDQ. However, no significant changes were seen in Physical Injury Fear sub-scale of the SCAS, in the DSRS or the Prosocial sub-scale of the SDQ. The effect sizes are mostly between small and medium. The teacher commented that the program was easy to use and found positive changes in classroom activities and personal relationships. This preliminary research showed the feasibility of the BCBT in a school setting. The results suggest that the BCBT offers effective treatment for reduction in anxiety and in difficult behaviors. There is a good prospect of the BCBT suggesting that BCBT may be easier to be delivered than CBT by Japanese teachers to promote child mental health. The study has limitations including no control group, small sample size, or a short teacher training. Future research should address these limitations.

Keywords: brief cognitive behavior therapy, cognitive behavior therapy, mental health services in schools, teacher training workshop

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Authors: Lan Cheng, Harry Qin, Yang Wang

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Background: COVID-19 has induced the largest digital learning experiment in history. There is also emerging research evidence that students have paid a high cost of learning loss from virtual learning. University-wide survey results demonstrate that digital learning remains difficult for students who struggle with learning challenges, isolation, or a lack of resources. Large-scale efforts are therefore increasingly utilized for digital education. To better prepare students in higher education for this grand scientific and technological transformation, STEM education has been prioritized and promoted as a strategic imperative in the ongoing curriculum reform essential for unfinished learning needs and whole-person development. Building upon five key elements identified in the STEM education literature: Problem-based Learning, Community and Belonging, Technology Skills, Personalization of Learning, Connection to the External Community, this case study explores the potential of pedagogical innovation that integrates computational and experimental methodologies to support, enrich, and navigate STEM education. Objectives: The goal of this case study is to create a high-fidelity prototype design for STEM education with knowledge transfer technology that contains a Cooperative Multi-Agent System (CMAS), which has the objectives of (1) conduct assessment to reveal a virtual learning mechanism and establish strategies to facilitate scientific learning engagement, accessibility, and connection within and beyond university setting, (2) explore and validate an interactional co-creation approach embedded in project-based learning activities under the STEM learning context, which is being transformed by both digital technology and student behavior change,(3) formulate and implement the STEM-oriented campaign to guide learning network mapping, mitigate the loss of learning, enhance the learning experience, scale-up inclusive participation. Methods: This study applied a case study strategy and a methodology informed by Social Network Analysis Theory within a cross-disciplinary communication paradigm (students, peers, educators). Knowledge transfer technology is introduced to address learning challenges and to increase the efficiency of Reinforcement Learning (RL) algorithms. A co-creation learning framework was identified and investigated in a context-specific way with a learning analytic tool designed in this study. Findings: The result shows that (1) CMAS-empowered learning support reduced students’ confusion, difficulties, and gaps during problem-solving scenarios while increasing learner capacity empowerment, (2) The co-creation learning phenomenon have examined through the lens of the campaign and reveals that an interactive virtual learning environment fosters students to navigate scientific challenge independently and collaboratively, (3) The deliverables brought from the STEM educational campaign provide a methodological framework both within the context of the curriculum design and external community engagement application. Conclusion: This study brings a holistic and coherent pedagogy to cultivates students’ interest in STEM and develop them a knowledge base to integrate and apply knowledge across different STEM disciplines. Through the co-designing and cross-disciplinary educational content and campaign promotion, findings suggest factors to empower evidence-based learning practice while also piloting and tracking the impact of the scholastic value of co-creation under the dynamic learning environment. The data nested under the knowledge transfer technology situates learners’ scientific journey and could pave the way for theoretical advancement and broader scientific enervators within larger datasets, projects, and communities.

Keywords: co-creation, cross-disciplinary, knowledge transfer, STEM education, social network analysis

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Authors: Qi Peng

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The Chinese sport sector is currently undergoing a dramatic institutional change. A sport system that was heavily dominated by the government is starting to shift towards one that is driven by the market. During the past sixty years, the Chinese Football Association (CFA), although ostensibly a ‘non-governmental organization’, has been in fact operated under the close supervision and control of the government. The double-identity of CFA has taken most of the blame for the poor performance of the Chinese football team, especially the men’s team. In 2015, a policy initiated by the Chinese government introduced a potentially radical change to the institutional structure of CFA by delegating the power of government agency – the General Administration of Sport of China - to the organization (CFA) itself. Against such background, an overarching research question was brought up- will an organization remained institutionalized within the system change in response to the external (policy) jolt? To answer this question, three principal data collection methods were employed: document review, participant observation and semi-structured interviews. Document review provides the mapping of the structural and cultural framework in which the CFA functions during the change process. The author have had the chance to interact closely with the organization as participant observer in the organization for a period of time, long enough to collect the data, but never too long to get biased view of the situation. This stage enables the author to gain an in-depth understanding of how CFA managed to restructure the governance and legitimacy. Conducting semi-structured interviews with staff within the CFA and from staff within selected stakeholders of CFA also provided a crucial step to gain an insight into the factors for change as well as the implications of the change. A wide range of interviewees that have been and to be interviewed include: CFA members (senior officials and staff); local football associations members; senior Chinese Super League football club managers; CFA Super League Co., LTD (senior officials and staff); CSL broadcasters; Chinese Olympic Committee members. The preliminary research data shows that the CFA is currently undergoing two levels of change: although the settings of CFA has been gradually restructured (organizational framework), the organizational values and beliefs remain almost the same as the CFA before the reform. This means that the plan of shifting from a governmental agency to an autonomous association is an going process, and that organizational core beliefs and values are more difficult to change than its structural framework. This is due to the inertia of the organizational history and the effect of institutionalization. The change of Chinese Football Association is looked at as a pioneering sport organization in China to undertake the “decoupling” road. It is believed that many other sport organizations, especially sport governing bodies will follow the step of CFA in the near future. Therefore, the experience of CFA change is worthy of studying.

Keywords: Chinese Football Association, Organizational Change, Organizational Culture, Structural Framework

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Authors: Cristina Costescu, Carmen David, Adrian Roșan

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Executive functions (EF) and emotion regulation strategies are processes that allow individuals to function in an adaptative way and to be goal-oriented, which is essential for success in daily living activities, at school, or in social contexts. The Emotion Regulation and Executive Functioning Scale for Children and Adolescents (REMEX) represents an empirically based tool (based on the model of EF developed by Diamond) for evaluating significant dimensions of child and adolescent EFs and emotion regulation strategies, mainly in school contexts. The instrument measures the following dimensions: working memory, inhibition, cognitive flexibility, executive attention, planning, emotional control, and emotion regulation strategies. Building the instrument involved not only a top-down process, as we selected the content in accordance with prominent models of FE, but also a bottom-up one, as we were able to identify valid contexts in which FE and ER are put to use. For the construction of the instrument, we implemented three focus groups with teachers and other professionals since the aim was to develop an accurate, objective, and ecological instrument. We used the focus group method in order to address each dimension and to yield a bank of items to be further tested. Each dimension is addressed through a task that the examiner will apply and through several items derived from the main task. For the validation of the instrument, we plan to use item response theory (IRT), also known as the latent response theory, that attempts to explain the relationship between latent traits (unobservable cognitive processes) and their manifestations (i.e., observed outcomes, responses, or performance). REMEX represents an ecological scale that integrates a current scientific understanding of emotion regulation and EF and is directly applicable to school contexts, and it can be very useful for developing intervention protocols. We plan to test his convergent validity with the Childhood Executive Functioning Inventory (CHEXI) and Emotion Dysregulation Inventory (EDI) and divergent validity between a group of typically developing children and children with neurodevelopmental disorders, aged between 6 and 9 years old. In a previous pilot study, we enrolled a sample of 40 children with autism spectrum disorders and attention-deficit/hyperactivity disorder aged 6 to 12 years old, and we applied the above-mentioned scales (CHEXI and EDI). Our results showed that deficits in planning, bebavior regulation, inhibition, and working memory predict high levels of emotional reactivity, leading to emotional and behavioural problems. Considering previous results, we expect our findings to provide support for the validity and reliability of the REMEX version as an ecological instrument for assessing emotion regulation and EF in children and for key features of its uses in intervention protocols.

Keywords: executive functions, emotion regulation, children, item response theory, focus group

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Authors: Maria Jose Granero Paris, Ana Isabel Jimenez Zarco, Agustin Pablo Alvarez Herranz

Abstract:

In the industrial sector collaboration with suppliers is key to the development of innovations in the field of processes. Access to resources and expertise that are not available in the business, obtaining a cost advantage, or the reduction of the time needed to carry out innovation are some of the benefits associated with the process. However, the success of this collaborative process is compromised, when from the beginning not clearly rules have been established that govern the relationship. Abundant studies developed in the field of innovation emphasize the strategic importance of the concept of “Governance”. Despite this, there have been few papers that have analyzed how the governance process of the relationship must be designed and managed to ensure the success of the collaboration process. The lack of literature in this area responds to the wide diversity of contexts where collaborative processes to innovate take place. Thus, in sectors such as the car industry there is a strong collaborative tradition between manufacturers and suppliers being part of the value chain. In this case, it is common to establish mechanisms and procedures that fix formal and clear objectives to regulate the relationship, and establishes the rights and obligations of each of the parties involved. By contrast, in other sectors, collaborative relationships to innovate are not a common way of working, particularly when their aim is the development of process improvements. It is in this case, it is when the lack of mechanisms to establish and regulate the behavior of those involved, can give rise to conflicts, and the failure of the cooperative relationship. Because of this the present paper analyzes the similarities and differences in the processes of governance in collaboration with suppliers in the European aerospace industry With these ideas in mind, we present research is twofold: Understand the importance of governance as a key element of the success of the collaboration in the development of product and process innovations, Establish the mechanisms and procedures to ensure the proper management of the processes of collaboration. Following the methodology of the case study, we analyze the way in which manufacturers and suppliers cooperate in the development of new products and processes in two industries with different levels of technological intensity and collaborative tradition: the automotive and aerospace. The identification of those elements playing a key role to establish a successful governance and relationship management and the compression of the mechanisms of regulation and control in place at the automotive sector can be use to propose solutions to some of the conflicts that currently arise in aerospace industry. The paper concludes by analyzing the strategic implications for the aerospace industry entails the adoption of some of the practices traditionally used in other industrial sectors. Finally, it is important to highlight that in this paper are presented the first results of a research project currently in progress describing a model of governance that explains the way to manage outsourced services to suppliers in the European aerospace industry, through the analysis of companies in the sector located in Germany, France and Spain.

Keywords: supplier collaboration, supplier relationship governance, innovation management, product innovation, process innovation

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Authors: C. P. Mallapur, U. K. Hulihalli, D. N. Kambrekar

Abstract:

Maize (Zea mays L.) an important cereal crop in the world has diversified uses including human consumption, animal feed, and industrial uses. A major constraint in low productivity of maize in India is undoubtedly insect pests particularly two species of stem borers, Chilo partellus (Swinhoe) and Sesamia inferens (Walker). The stem borers cause varying level of yield losses in different agro-climate regions (25.7 to 80.4%) resulting in a huge economic loss to the farmers. Although these pests are rather difficult to manage, efforts have been made to combat the menace by using effective insecticides. However, efforts have been made in the present study to integrate various possible approaches for sustainable management of these borers. Two field experiments were conducted separately during 2016-17 at Main Agricultural Research Station, University of Agricultural Sciences, Dharwad, Karnataka, India. In the first experiment, six treatments were randomized in RBD. The insect eggs at pinhead stage (@ 40 eggs/plant) were stapled to the under surface of leaves covering 15-20 % of plants in each plot after 15 days of sowing. The second experiment was planned with nine treatments replicated thrice. The border crop with NB -21 grass was planted all around the plots in the specific treatments while, cowpea intercrop (@6:1-row proportion) was sown along with the main crop and later, the insecticidal spray with chlorantraniliprole and nimbecidine was taken upon need basis in the specific treatments. The results indicated that the leaf injury and dead heart incidence were relatively more in the treatments T₂ and T₄ wherein, no insect control measures were made after the insect release (58.30 & 40.0 % leaf injury and 33.42 and 25.74% dead heart). On the contrary, these treatments recorded higher stem tunneling (32.4 and 24.8%) and resulted in lower grain yield (17.49 and 26.79 q/ha) compared to 29.04, 32.68, 40.93 and 46.38 q/ha recorded in T₁, T₃, T₅ and T₆ treatments, respectively. A maximum yield loss of 28.89 percent was noticed in T₂ followed by 19.59 percent in T₄ where no sprays were imposed. The data on integrated management trial revealed the lowest stem borer damage (19.28% leaf injury and 1.21% dead heart) in T₅ (seed treatment with thiamethoxam 70FS @ 8ml/kg seed + cow intercrop along with nimbecidine 0.03EC @ 5.0 ml/l and chlorantraniliprole 18.5SC spray @ 0.2 ml/l). The next best treatment was T₆ (ST+ NB-21 borer with nimbecidine and chlorantraniliprole spray) with 21.3 and 1.99 percent leaf injury and dead heart incidence, respectively. These treatments resulted in highest grain yield (77.71 and 75.53 q/ha in T₅ and T₆, respectively) compared to the standard check, T₁ (ST+ chlorantraniliprole spray) wherein, 27.63 percent leaf injury and 3.68 percent dead heart were noticed with 60.14 q/ha grain yield. The stem borers can cause yield loss up to 25-30 percent in maize which can be well tackled by seed treatment with thiamethoxam 70FS @ 8ml/kg seed and sowing the crop along with cowpea as intercrop (6:1 row proportion) or NB-21 grass as border crop followed by application of nimbecidine 0.03EC @ 5.0 ml/l and chlorantraniliprole 18.5SC @ 0.2 ml/l on need basis.

Keywords: Maize stem borers, Chilo partellus, Sesamia inferens, crop loss, integrated management

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Authors: Fabio N. Moreno, Letícia B. Marinho, Beatriz D. Ruiz, Maria Helena R. B. Martins

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Brazil is a top consumer of pesticides worldwide, and the São Paulo State is one of the highest consumers among the Brazilian federative states. However, representative data about the occurrence of pesticides in surface waters of the São Paulo State is scarce. This paper aims to present the results of pesticides monitoring executed within the Water Quality Monitoring Network of CETESB (The Environmental Agency of the São Paulo State) between the 2018-2022 period. Surface water sampling points (21 to 25) were selected within basins of predominantly agricultural land-use (5 to 85% of cultivated areas). The samples were collected throughout the year, including high-flow and low-flow conditions. The frequency of sampling varied between 6 to 4 times per year. Selection of pesticide molecules for monitoring followed a prioritizing process from EMBRAPA (Brazilian Agricultural Research Corporation) databases of pesticide use. Pesticides extractions in aqueous samples were performed according to USEPA 3510C and 3546 methods following quality assurance and quality control procedures. Determination of pesticides in water (ng L-1) extracts were performed by high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS) and by gas chromatography with nitrogen phosphorus (GC-NPD) and electron capture detectors (GC-ECD). The results showed higher frequencies (20- 65%) in surface water samples for Carbendazim (fungicide), Diuron/Tebuthiuron (herbicides) and Fipronil/Imidaclopride (insecticides). The frequency of observations for these pesticides were generally higher in monitoring points located in sugarcane cultivated areas. The following pesticides were most frequently quantified above the Aquatic life benchmarks for freshwater (USEPA Office of Pesticide Programs, 2023) or Brazilian Federal Regulatory Standards (CONAMA Resolution no. 357/2005): Atrazine, Imidaclopride, Carbendazim, 2,4D, Fipronil, and Chlorpiryfos. Higher median concentrations for Diuron and Tebuthiuron in the rainy months (october to march) indicated pesticide transport through surface runoff. However, measurable concentrations in the dry season (april to september) for Fipronil and Imidaclopride also indicates pathways related to subsurface or base flow discharge after pesticide soil infiltration and leaching or dry deposition following pesticide air spraying. With exception to Diuron, no temporal trends related to median concentrations of the most frequently quantified pesticides were observed. These results are important to assist policymakers in the development of strategies aiming at reducing pesticides migration to surface waters from agricultural areas. Further studies will be carried out in selected points to investigate potential risks as a result of pesticides exposure on aquatic biota.

Keywords: pesticides monitoring, são paulo state, water quality, surface waters

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Authors: Syed Benazir Firdaus, Debosree Ghosh, Aindrila Chattyopadhyay, Kuladip Jana, Debasish Bandyopadhyay

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Gastro-toxic effect of piroxicam, a classical non-steroidal anti-inflammatory drug (NSAID), has restricted its use in arthritis and similar diseases. The present study aims to find if a combination of melatonin and Murraya koenigii leaf extract therapy can protect against piroxicam induced ulcerative damage in rats. For this study, rats were divided into four groups namely control group where rats were orally administered distilled water, only combination treated group, piroxicam treated group and combination pre-administered piroxicam treated group. Each group of rats consisted of six animals. Melatonin at a dose of 20mg/kg body weight and antioxidant rich Murraya koenigii leaf extract at a dose of 50 mg /kg body weight were successively administered at 30 minutes interval one hour before oral administration of piroxicam at a dose of 30 mg/kg body weight to Wistar rats in the combination pre-administered piroxicam treated group. The rats of the animal group which was only combination treated were administered both the drugs respectively without piroxicam treatment whereas the piroxicam treated animal group was administered only piroxicam at 30mg/kg body weight without any pre-treatment with the combination. Macroscopic examination along with histo-pathological study of gastric tissue using haemotoxylin-eosin staining and alcian blue dye staining showed protection of the gastric mucosa in the combination pre-administered piroxicam treated group. Determination of adherent mucus content biochemically and collagen content through Image J analysis of picro-sirius stained sections of rat gastric tissue also revealed protective effects of the combination in piroxicam mediated toxicity. Gelatinolytic activity of piroxicam was significantly reduced by pre-administration of the drugs which was well exhibited by the gelatin zymography study of the rat gastric tissue. Mean ulcer index determined from macroscopic study of rat stomach reduced to a minimum (0±0.00; Mean ± Standard error of mean and number of animals in the group=6) indicating the absence of ulcer spots on pre-treatment of rats with the combination. Gastro-friendly prostaglandin (PGE2) which otherwise gets depleted on piroxicam treatment was also well protected when the combination was pre-administered in the rats prior to piroxicam treatment. The requirement of the individual drugs in low doses in this combinatorial therapeutic approach will possibly minimize the cost of therapy as well as it will eliminate the possibility of any pro-oxidant side effects on the use of high doses of antioxidants. Beneficial activity of this combination therapy in the rat model raises the possibility that similar protective actions might be also observed if it is adopted by patients consuming NSAIDs like piroxicam. However, the introduction of any such therapeutic approach is subject to future studies in human.

Keywords: gastro-protective action, melatonin, Murraya koenigii leaf extract, piroxicam

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Authors: Tso Sheng-Yang, Wang Tien-Ni

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Introduction and Purpose: Previous researchers have documented children with ASD (Autism Spectrum Disorders) prefer to escaping internal privates and external privates when they face tough conditions they can’t control or they don’t like.Especially, when children with ASD need to learn challenging tasks, such us Chinese language, their inappropriate behaviors will occur apparently. Recently, researchers apply positive behavior support strategies for children with ASD to enhance their self-efficacy and therefore to reduce their adverse behaviors. Thus, the purpose of this research was to design a series of lecture based on art therapy and to evaluate its effectiveness on the child’s self-efficacy. Method: This research was the single-case design study that recruited a high school boy with ASD. Whole research can be separated into three conditions. First, baseline condition, before the class started and ended, the researcher collected participant’s competencies of self-efficacy every session. In intervention condition, the research used dramatic conventions to teach the child in Chinese language twice a week.When the data was stable across three documents, the period entered to the maintenance condition. In maintenance condition, the researcher only collected the score of self-efficacynot to do other interventions five times a month to represent the effectiveness of maintenance.The time and frequency of data collection among three conditions are identical. Concerning art therapy, the common approach, e.g., music, drama, or painting is to use art medium as independent variable. Due to visual cues of art medium, the ASD can be easily to gain joint attention with teachers. Besides, the ASD have difficulties in understanding abstract objectives Thus, using the drama convention is helpful for the ASD to construct the environment and understand the context of Classical Chinese. By real operation, it can improve the ASD to understand the context and construct prior knowledge. Result: Bassd on the 10-points Likert scale and research, we product following results. (a) In baseline condition, the average score of self-efficacyis 1.12 points, rangedfrom 1 to 2 points, and the level change is 0 point. (b)In intervention condition, the average score of self-efficacy is 7.66 points rangedfrom 7 to 9 points, and the level change is 1 point. (c)In maintenance condition, the average score of self-efficacy is 6.66 points rangedfrom 6 to 7 points, and the level change is 1 point. Concerning immediacy of change, between baseline and intervention conditions, the difference is 5 points. No overlaps were found between these two conditions. Conclusion: According to the result, we find that it is effective that using dramatic conventions a s teaching strategies to teach children with ASD. The result presents the score of self-efficacyimmediately enhances when the dramatic conventions commences. Thus, we suggest the teacher can use this approach and adjust, based on the student’s trait, to teach the ASD on difficult task.

Keywords: dramatic conventions, autism spectrum disorder, slef-efficacy, teaching strategy

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Authors: Andres Mejia-Ortiz, Catalina Lozada, German R. Santos, Rafael Angulo-Jaramillo, Bernardo Caicedo

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The interaction between atmospheric variables and soil properties is a determining factor when evaluating the flow of water through the soil. This interaction situation directly determines the behavior of the soil and greatly influences the changes that occur in it. The atmospheric variations such as changes in the relative humidity, air temperature, wind velocity and precipitation, are the external variables that reflect a greater incidence in the changes that are generated in the subsoil, as a consequence of the water flow in descending and ascending conditions. These environmental variations have a major importance in the study of the soil because the conditions of humidity and temperature in the soil surface depend on them. In addition, these variations control the thickness of the unsaturated zone and the position of the water table with respect to the surface. However, understanding the relationship between the atmosphere and the soil is a somewhat complex aspect. This is mainly due to the difficulty involved in estimating the changes that occur in the soil from climate changes; since this is a coupled process where act processes of mass transfer and heat. In this research, an experimental field was implemented to study in-situ the interaction between the atmosphere and the soft soils of the city of Bogota, Colombia. The soil under study consists of a 60 cm layer composed of two silts of similar characteristics at the surface and a deep soft clay deposit located under the silky material. It should be noted that the vegetal layer and organic matter were removed to avoid the evapotranspiration phenomenon. Instrumentation was carried on in situ through a field disposal of many measuring devices such as soil moisture sensors, thermocouples, relative humidity sensors, wind velocity sensor, among others; which allow registering the variations of both the atmospheric variables and the properties of the soil. With the information collected through field monitoring, the water balances were made using the Hydrus-1D software to determine the flow conditions that developed in the soil during the study. Also, the moisture profile for different periods and time intervals was determined by the balance supplied by Hydrus 1D; this profile was validated by experimental measurements. As a boundary condition, the actual evaporation rate was included using the semi-empirical equations proposed by different authors. In this study, it was obtained for the rainy periods a descending flow that was governed by the infiltration capacity of the soil. On the other hand, during dry periods. An increase in the actual evaporation of the soil induces an upward flow of water, increasing suction due to the decrease in moisture content. Also, cracks were developed accelerating the evaporation process. This work concerns to the study of soil-atmosphere interaction through the experimental field and it is a very useful tool since it allows considering all the factors and parameters of the soil in its natural state and real values of the different environmental conditions.

Keywords: field monitoring, soil-atmosphere, soft soils, soil-water balance

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