Search results for: cumulative exposure model
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 18751

Search results for: cumulative exposure model

18181 Edmodo and the Three Powerful Strategies to Maximize Students Learning

Authors: Aziz Soubai

Abstract:

The primary issue is that English as foreign language learners don’t use English outside the classroom. The only little exposure is inside the classroom, and that’s not enough to make them good language learners! Edmodo, like the other Learning Management Systems, can be used to encourage students to collaborate with each other and with global classrooms on projects where English is used- Some examples of collaboration with different schools will be mentioned and how the Substitution Augmentation Modification Redefinition (SAMR) model and its stages can be applied in the activities, especially for teachers who are hesitant to introduce technology or don’t have a lot of technical knowledge. There will also be some focus on Edmodo groups and on how flipped and blended learning can be used as an extension for classroom time and to help the teacher address language problems and improve students’ language skills, especially writing, reading and communication. It is also equally important to use Edmodo badges and certificates for motivating and engaging learners and gamifying the lesson.

Keywords: EFL learners, language classroom-learning management system, edmodo, SAMR, language skills

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18180 Structural Equation Modeling Semiparametric Truncated Spline Using Simulation Data

Authors: Adji Achmad Rinaldo Fernandes

Abstract:

SEM analysis is a complex multivariate analysis because it involves a number of exogenous and endogenous variables that are interconnected to form a model. The measurement model is divided into two, namely, the reflective model (reflecting) and the formative model (forming). Before carrying out further tests on SEM, there are assumptions that must be met, namely the linearity assumption, to determine the form of the relationship. There are three modeling approaches to path analysis, including parametric, nonparametric and semiparametric approaches. The aim of this research is to develop semiparametric SEM and obtain the best model. The data used in the research is secondary data as the basis for the process of obtaining simulation data. Simulation data was generated with various sample sizes of 100, 300, and 500. In the semiparametric SEM analysis, the form of the relationship studied was determined, namely linear and quadratic and determined one and two knot points with various levels of error variance (EV=0.5; 1; 5). There are three levels of closeness of relationship for the analysis process in the measurement model consisting of low (0.1-0.3), medium (0.4-0.6) and high (0.7-0.9) levels of closeness. The best model lies in the form of the relationship X1Y1 linear, and. In the measurement model, a characteristic of the reflective model is obtained, namely that the higher the closeness of the relationship, the better the model obtained. The originality of this research is the development of semiparametric SEM, which has not been widely studied by researchers.

Keywords: semiparametric SEM, measurement model, structural model, reflective model, formative model

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18179 Acrylamide-Induced Acute Nephrotoxicity in Rats

Authors: Keivan Jamshidi, Afshin Zahedi

Abstract:

Acrylamide (ACR) has been shown to cause neurotoxic effects in humans and neurotoxic, genotoxic, reproductive, and carcinogenic effects in laboratory animals. To investigate the nephrotoxic effect of Acrylamide (ACR), 50 adult male rats (Wistar, approximately 250 g) housed in polycarbonate boxes as 5 per each, and randomly assigned in 5 groups including 4 exposure groups as A, B, C, and D groups of rats (10 rats per exposure group., total) and were exposed to 0.5, 5, 50, 100 mg/kg ACR per day×11days i.p. respectively. The remaining 10 rats were housed in group (E) as control group. Control rats received daily i.p. injections of 0.9% saline (3ml/kg). On day 12, four rats, were randomly selected, perfused , dissected and proper samples were collected from their kidneys. Results of histopathological studies based on H&E technique did show no morphologic changes in kidneys of rats belong to groups A, B and E, while moderate to severe morphologic changes including glomerular hypercellularity, global pattern of proliferative glomerulonephritis, occupation of capsular space, tubular cell swelling and hyaline cast formation, were observed in different stained sections obtained from the kidneys of rats belong to group, C, and D. This finding, beside neurotoxic, reproductive and carcinogenic effects, seems to indicate for the first time another important aspect of toxic effect of ACR, i.e., acute nephrotoxicity.

Keywords: acrylamide, nephrotoxicity, glomerulonephritis, rats

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18178 Concomitant Exposure of Bacoside A and Bromelain Relieves Dichlorvos Toxicity in Mice Serum

Authors: Sonam Agarwal, Renu Bist

Abstract:

Current study emphasizes the toxic effects of dichlorvos on serum in terms of oxidative stress. Meanwhile, a protective action of bacoside A and bromelain was investigated against the biochemical alterations in serum. The experimental design included six groups of mice: saline was given as a vehicle to the control mice (group I). Mice belonging to groups II, III and IV, were administered with dichlorvos (40 mg/kg b.w.), bromelain and bacoside A, respectively. The fifth group received a combination of bromelain and bacoside A. In group VI, Bacoside A, and bromelain were administered 20 minutes prior to exposure of dichlorvos. Thiobarbituric acid reactive substances (TBARS), protein carbonyl content (PCC), catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) and reduced glutathione (GSH) level were used as biochemical test of toxic action for dichlorvos intoxication. Significantly increased TBARS and PCC level in second group suggests that dichlorvos enhances the production of free radicals in serum of mice (p< 0.05). Antioxidants treatment significantly decreased the levels of TBARS and PCC (p< 0.05). Dichlorvos administration causes a significant reduction in the level of CAT, SOD, GPx and GSH (p< 0.05) which was restored significantly by co-administration of bromelain and Bacoside A in dichlorvos exposed mice (p< 0.05). Treatment of bromelain and Bacoside A in combination served as better scavengers of toxicity induced by dichlorvos.

Keywords: bacoside A, bromelain, dichlorvos, serum

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18177 Metabolic Predictive Model for PMV Control Based on Deep Learning

Authors: Eunji Choi, Borang Park, Youngjae Choi, Jinwoo Moon

Abstract:

In this study, a predictive model for estimating the metabolism (MET) of human body was developed for the optimal control of indoor thermal environment. Human body images for indoor activities and human body joint coordinated values were collected as data sets, which are used in predictive model. A deep learning algorithm was used in an initial model, and its number of hidden layers and hidden neurons were optimized. Lastly, the model prediction performance was analyzed after the model being trained through collected data. In conclusion, the possibility of MET prediction was confirmed, and the direction of the future study was proposed as developing various data and the predictive model.

Keywords: deep learning, indoor quality, metabolism, predictive model

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18176 The Positive Effects of Processing Instruction on the Acquisition of French as a Second Language: An Eye-Tracking Study

Authors: Cecile Laval, Harriet Lowe

Abstract:

Processing Instruction is a psycholinguistic pedagogical approach drawing insights from the Input Processing Model which establishes the initial innate strategies used by second language learners to connect form and meaning of linguistic features. With the ever-growing use of technology in Second Language Acquisition research, the present study uses eye-tracking to measure the effectiveness of Processing Instruction in the acquisition of French and its effects on learner’s cognitive strategies. The experiment was designed using a TOBII Pro-TX300 eye-tracker to measure participants’ default strategies when processing French linguistic input and any cognitive changes after receiving Processing Instruction treatment. Participants were drawn from lower intermediate adult learners of French at the University of Greenwich and randomly assigned to two groups. The study used a pre-test/post-test methodology. The pre-tests (one per linguistic item) were administered via the eye-tracker to both groups one week prior to instructional treatment. One group received full Processing Instruction treatment (explicit information on the grammatical item and on the processing strategies, and structured input activities) on the primary target linguistic feature (French past tense imperfective aspect). The second group received Processing Instruction treatment except the explicit information on the processing strategies. Three immediate post-tests on the three grammatical structures under investigation (French past tense imperfective aspect, French Subjunctive used for the expression of doubt, and the French causative construction with Faire) were administered with the eye-tracker. The eye-tracking data showed the positive change in learners’ processing of the French target features after instruction with improvement in the interpretation of the three linguistic features under investigation. 100% of participants in both groups made a statistically significant improvement (p=0.001) in the interpretation of the primary target feature (French past tense imperfective aspect) after treatment. 62.5% of participants made an improvement in the secondary target item (French Subjunctive used for the expression of doubt) and 37.5% of participants made an improvement in the cumulative target feature (French causative construction with Faire). Statistically there was no significant difference between the pre-test and post-test scores in the cumulative target feature; however, the variance approximately tripled between the pre-test and the post-test (3.9 pre-test and 9.6 post-test). This suggests that the treatment does not affect participants homogenously and implies a role for individual differences in the transfer-of-training effect of Processing Instruction. The use of eye-tracking provides an opportunity for the study of unconscious processing decisions made during moment-by-moment comprehension. The visual data from the eye-tracking demonstrates changes in participants’ processing strategies. Gaze plots from pre- and post-tests display participants fixation points changing from focusing on content words to focusing on the verb ending. This change in processing strategies can be clearly seen in the interpretation of sentences in both primary and secondary target features. This paper will present the research methodology, design and results of the experimental study using eye-tracking to investigate the primary effects and transfer-of-training effects of Processing Instruction. It will then provide evidence of the cognitive benefits of Processing Instruction in Second Language Acquisition and offer suggestion in second language teaching of grammar.

Keywords: eye-tracking, language teaching, processing instruction, second language acquisition

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18175 Model Averaging in a Multiplicative Heteroscedastic Model

Authors: Alan Wan

Abstract:

In recent years, the body of literature on frequentist model averaging in statistics has grown significantly. Most of this work focuses on models with different mean structures but leaves out the variance consideration. In this paper, we consider a regression model with multiplicative heteroscedasticity and develop a model averaging method that combines maximum likelihood estimators of unknown parameters in both the mean and variance functions of the model. Our weight choice criterion is based on a minimisation of a plug-in estimator of the model average estimator's squared prediction risk. We prove that the new estimator possesses an asymptotic optimality property. Our investigation of finite-sample performance by simulations demonstrates that the new estimator frequently exhibits very favourable properties compared to some existing heteroscedasticity-robust model average estimators. The model averaging method hedges against the selection of very bad models and serves as a remedy to variance function misspecification, which often discourages practitioners from modeling heteroscedasticity altogether. The proposed model average estimator is applied to the analysis of two real data sets.

Keywords: heteroscedasticity-robust, model averaging, multiplicative heteroscedasticity, plug-in, squared prediction risk

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18174 Reliability Prediction of Tires Using Linear Mixed-Effects Model

Authors: Myung Hwan Na, Ho- Chun Song, EunHee Hong

Abstract:

We widely use normal linear mixed-effects model to analysis data in repeated measurement. In case of detecting heteroscedasticity and the non-normality of the population distribution at the same time, normal linear mixed-effects model can give improper result of analysis. To achieve more robust estimation, we use heavy tailed linear mixed-effects model which gives more exact and reliable analysis conclusion than standard normal linear mixed-effects model.

Keywords: reliability, tires, field data, linear mixed-effects model

Procedia PDF Downloads 563
18173 A Fast and Cost-Effective Method to Monitor Microplastics in Compost and Soiduration of Enterococcus Faecalis Penetration in Environmentally Exposed Root Canals Obturated With Lateral Condensation Technique

Authors: N. Thawornwisit, P. Pradoo, S. Nuypree, L. Jarukasetrporn, S. Jitpukdeebodintra

Abstract:

Objective: The aim of this study was to evaluate the duration of the Enterococcus faecalis (E. faecalis) penetration into the gap between root canal wall and filling material at a 3 to 6 mm distance from the cementoenamel junction (CEJ) in the dislodged temporary filling, in vitro. Material and methods: Thirty-four single root canal mandibular premolars were divided into two experimental groups (N = 15) and one negative control (N = 4). Root canals were prepared and obturated with gutta-percha using lateral condensation technique, X-ray checked, and sterilized. Leakages were set up using the modified bacterial leakage model, and E. faecalis was used as a microbial marker. Leakages were evaluated at 3 and 7 days by culturing gutta-percha and dentine drilled from a 3-6 mm distance from CEJ. Broth turbidity was recorded and compared. Result: All four negative control and the 3-day experimental group showed no broth turbidity. For the 7-day experimental group, there was 33.3% leakage. Conclusion: Penetration of E. faecalis into the gap between root canal wall and filling material at a 3 to 6 mm distance from CEJ in the dislodged temporary filling were not found at three days. However, at seven days of exposure, bacteria could penetrate into the interface of the root canal and filling materials.

Keywords: coronal leakage, bacterial leakage model, enterococcus faecalis

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18172 Towards a Measurement-Based E-Government Portals Maturity Model

Authors: Abdoullah Fath-Allah, Laila Cheikhi, Rafa E. Al-Qutaish, Ali Idri

Abstract:

The e-government emerging concept transforms the way in which the citizens are dealing with their governments. Thus, the citizens can execute the intended services online anytime and anywhere. This results in great benefits for both the governments (reduces the number of officers) and the citizens (more flexibility and time saving). Therefore, building a maturity model to assess the e-government portals becomes desired to help in the improvement process of such portals. This paper aims at proposing an e-government maturity model based on the measurement of the best practices’ presence. The main benefit of such maturity model is to provide a way to rank an e-government portal based on the used best practices, and also giving a set of recommendations to go to the higher stage in the maturity model.

Keywords: best practices, e-government portal, maturity model, quality model

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18171 Changing Body Ideals of Ethnically Diverse Gay and Heterosexual Men and the Proliferation of Social and Entertainment Media

Authors: Cristina Azocar, Ivana Markova

Abstract:

A survey of 565 male undergraduates examined the effects of exposure to social networking sites and entertainment media on young men’s body image. Exposure to social and to entertainment media was found to have negative effects on men’s body satisfaction, social comparison, and thin ideal internalization. Findings indicated significant differences in those men who were more exposed to social and to entertainment media than those who were not as exposed. Consistent with past studies, gay men were found to be more dissatisfied with their bodies than straight men. Gay men compared themselves to other better-looking individuals and internalized ideal body types seen in media significantly more than their straight counterparts. Surprisingly, straight men seem to care as much about their physical attractiveness/appearance as gay men do, but only in public settings such as at the beach, at athletic events (including gyms) and social events. Although on average ethnic groups were more similar than different, small but significant differences occurred with Asian men indicating significantly higher body dissatisfaction than White/European men and Middle Eastern/Arab men their counterparts. The study increases our knowledge about SNS and entertainment use and its associated body image, and body satisfaction affects among low-income ethnic minority men.

Keywords: body dissatisfaction, body image, entertainment media, gay men, race and ethnicity, social economic status, social comparison, social media

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18170 Impact of Mhealth Tools on Psycho-Social Predictors of Behaviour Regarding Contraceptive Use

Authors: Preeti Tiwari, Jay Wood, Duncan Babbage

Abstract:

Family planning plays a role in saving lives across the globe by preventing unwanted pregnancies. The purpose of this multidisciplinary research was to determine the impact of mHealth tools have on psychosocial determinants of behaviour for family planning. The present study examines a topic that is very relevant in times where human-technology interaction is at its peak. It is probably one of the first studies that have investigated the impact of mobile phone technology on the underlying mechanisms of behaviour change for family planning using primary data. To examine the association between exposure to mHealth tools and predictors of behaviour, data was collected from mHealth intervention areas in India. A post-intervention quasi-experimental study with a 2x2 factorial design was conducted among 831 men and women from the state of Bihar. The quantitative data analysis evaluated the extent of influence that predictors of behaviour (beliefs, social norms, perceived behaviour control, and outcome behaviour) have on a woman’s decisions about family planning. The results indicated an association between exposure to mHealth tools and improved communication about family planning among various family members after receiving health information from a health worker (H1). A relationship between exposure to mHealth tools and increased support women received from their husbands and extended family (mothers-in-law specifically) and peers (H2) was also found. A further result showed that knowledge about family planning was greater among users of family planning (H4). mHealth tools empower women to communicate with family members. This has important implications for developing mobile phone-based tools, as they can be used as a crucial communication channel that can be an effective method of increasing communication among family members about contraceptives. Thus, it can be implied that where women feel nervous talking about contraception, the successful application of mHealth tools can strengthen the interactivity of the health communication and could increase the likelihood of using contraception. However, while it may improve health communication that can inform health decisions, it may be insufficient on its own to cause behaviour change.

Keywords: contraceptive, e-health, psycho-social, women

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18169 CFD Simulation of a Large Scale Unconfined Hydrogen Deflagration

Authors: I. C. Tolias, A. G. Venetsanos, N. Markatos

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In the present work, CFD simulations of a large scale open deflagration experiment are performed. Stoichiometric hydrogen-air mixture occupies a 20 m hemisphere. Two combustion models are compared and are evaluated against the experiment. The Eddy Dissipation Model and a Multi-physics combustion model which is based on Yakhot’s equation for the turbulent flame speed. The values of models’ critical parameters are investigated. The effect of the turbulence model is also examined. k-ε model and LES approach were tested.

Keywords: CFD, deflagration, hydrogen, combustion model

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18168 A Framework for Consumer Selection on Travel Destinations

Authors: J. Rhodes, V. Cheng, P. Lok

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The aim of this study is to develop a parsimonious model that explains the effect of different stimulus on a tourist’s intention to visit a new destination. The model consists of destination trust and interest as the mediating variables. The model was tested using two different types of stimulus; both studies empirically supported the proposed model. Furthermore, the first study revealed that advertising has a stronger effect than positive online reviews. The second study found that the peripheral route of the elaboration likelihood model has a stronger influence power than the central route in this context.

Keywords: advertising, electronic word-of-mouth, elaboration likelihood model, intention to visit, trust

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18167 Using Teachers' Perceptions of Science Outreach Activities to Design an 'Optimum' Model of Science Outreach

Authors: Victoria Brennan, Andrea Mallaburn, Linda Seton

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Science outreach programmes connect school pupils with external agencies to provide activities and experiences that enhance their exposure to science. It can be argued that these programmes not only aim to support teachers with curriculum engagement and promote scientific literacy but also provide pivotal opportunities to spark scientific interest in students. In turn, a further objective of these programmes is to increase awareness of career opportunities within this field. Although outreach work is also often described as a fun and satisfying venture, a plethora of researchers express caution to how successful the processes are to increases engagement post-16 in science. When researching the impact of outreach programmes, it is often student feedback regarding the activities or enrolment numbers to particular science courses post-16, which are generated and analysed. Although this is informative, the longevity of the programme’s impact could be better informed by the teacher’s perceptions; the evidence of which is far more limited in the literature. In addition, there are strong suggestions that teachers can have an indirect impact on a student’s own self-concept. These themes shape the focus and importance of this ongoing research project as it presents the rationale that teachers are under-used resources when it comes to considering the design of science outreach programmes. Therefore, the end result of the research will consist of a presentation of an ‘optimum’ model of outreach. The result of which should be of interest to the wider stakeholders such as universities or private or government organisations who design science outreach programmes in the hope to recruit future scientists. During phase one, questionnaires (n=52) and interviews (n=8) have generated both quantitative and qualitative data. These have been analysed using the Wilcoxon non-parametric test to compare teachers’ perceptions of science outreach interventions and thematic analysis for open-ended questions. Both of these research activities provide an opportunity for a cross-section of teacher opinions of science outreach to be obtained across all educational levels. Therefore, an early draft of the ‘optimum’ model of science outreach delivery was generated using both the wealth of literature and primary data. This final (ongoing) phase aims to refine this model using teacher focus groups to provide constructive feedback about the proposed model. The analysis uses principles of modified Grounded Theory to ensure that focus group data is used to further strengthen the model. Therefore, this research uses a pragmatist approach as it aims to focus on the strengths of the different paradigms encountered to ensure the data collected will provide the most suitable information to create an improved model of sustainable outreach. The results discussed will focus on this ‘optimum’ model and teachers’ perceptions of benefits and drawbacks when it comes to engaging with science outreach work. Although the model is still a ‘work in progress’, it provides both insight into how teachers feel outreach delivery can be a sustainable intervention tool within the classroom and what providers of such programmes should consider when designing science outreach activities.

Keywords: educational partnerships, science education, science outreach, teachers

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18166 A Combined AHP-GP Model for Selecting Knowledge Management Tool

Authors: Ahmad Sarfaraz, Raiyad Herwies

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In this paper, a multi-criteria decision making analysis is used to help any organization selects the best KM tool that fits and serves its needs. The AHP model is used based on a previous study to highlight and identify the main criteria and sub-criteria that are incorporated in the selection process. Different KM tools alternatives with different criteria are compared and weighted accurately to be incorporated in the GP model. The main goal is to combine the GP model with the AHP model to ensure that selecting the KM tool considers the resource constraints. Two important issues are discussed in this paper: how different factors could be taken into consideration in forming the AHP model, and how to incorporate the AHP results into the GP model for better results.

Keywords: knowledge management, analytical hierarchy process, goal programming, multi-criteria decision making

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18165 Theoretical Research for Influence of Irradiation on Transient Creep of Metals

Authors: Pavlo Selyshchev, Tetiana Didenko

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Via formalism of the Complex systems and in the framework of the climb - glide model a theoretical approach to describe the influence of irradiation on transient creep of metals. We consider metal under such stress and conditions of irradiation at which creep is determined by dislocation motion that consists in climb and glide. It is shown that there are qualitatively different regimes of a creep as a result of irradiation. Simulation and analysis of this phenomenon are performed. The time dependence of creep rate of metal under an irradiation is theoretically obtained. The conditions of zero minimums of the creep-rate existence as well as the times of their appearance are determined. The changing of the position of creep-rate dips in the conditions of the temperature exposure change is investigated. The obtained results are compared with the experimentally observed dependence of the creep rate on time.

Keywords: creep, climb and glide of dislocations, irradiation, non-linear feed-back, point defects

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18164 Diversity for Safety and Security of Autonomous Vehicles against Accidental and Deliberate Faults

Authors: Anil Ranjitbhai Patel, Clement John Shaji, Peter Liggesmeyer

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Safety and security of autonomous vehicles (AVs) is a growing concern, first, due to the increased number of safety-critical functions taken over by automotive embedded systems; second, due to the increased exposure of the software-intensive systems to potential attackers; third, due to dynamic interaction in an uncertain and unknown environment at runtime which results in changed functional and non-functional properties of the system. Frequently occurring environmental uncertainties, random component failures, and compromise security of the AVs might result in hazardous events, sometimes even in an accident, if left undetected. Beyond these technical issues, we argue that the safety and security of AVs against accidental and deliberate faults are poorly understood and rarely implemented. One possible way to overcome this is through a well-known diversity approach. As an effective approach to increase safety and security, diversity has been widely used in the aviation, railway, and aerospace industries. Thus, the paper proposes fault-tolerance by diversity model takes into consideration the mitigation of accidental and deliberate faults by application of structure and variant redundancy. The model can be used to design the AVs with various types of diversity in hardware and software-based multi-version system. The paper evaluates the presented approach by employing an example from adaptive cruise control, followed by discussing the case study with initial findings.

Keywords: autonomous vehicles, diversity, fault-tolerance, adaptive cruise control, safety, security

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18163 Long Short-Time Memory Neural Networks for Human Driving Behavior Modelling

Authors: Lu Zhao, Nadir Farhi, Yeltsin Valero, Zoi Christoforou, Nadia Haddadou

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In this paper, a long short-term memory (LSTM) neural network model is proposed to replicate simultaneously car-following and lane-changing behaviors in road networks. By combining two kinds of LSTM layers and three input designs of the neural network, six variants of the LSTM model have been created. These models were trained and tested on the NGSIM 101 dataset, and the results were evaluated in terms of longitudinal speed and lateral position, respectively. Then, we compared the LSTM model with a classical car-following model (the intelligent driving model (IDM)) in the part of speed decision. In addition, the LSTM model is compared with a model using classical neural networks. After the comparison, the LSTM model demonstrates higher accuracy than the physical model IDM in terms of car-following behavior and displays better performance with regard to both car-following and lane-changing behavior compared to the classical neural network model.

Keywords: traffic modeling, neural networks, LSTM, car-following, lane-change

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18162 Acrylamide-Induced Thoracic Spinal Cord Axonopathy

Authors: Afshin Zahedi, Keivan Jamshidi

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This study was conducted to determine the neurotoxic effects of different doses of ACR on the thoracic axons of the spinal cord of rat. To evaluate this hypothesis in the thoracic axons, amino-cupric silver staining technique of the de Olmos was conducted to define the histopathologic characteristic (argyrophilia) of axonal damage following ACR exposure. For this purpose 60 adult male rats (Wistar, approximately 250 g) were selected. Rats were hosed in polycarbonate boxes as two per each. Randomly assigned groups of rats (10 rats per exposure group, total 5 exposure groups as A, B, C, D and E) were exposed to 0.5, 5, 50, 100 and 500 mg/kg per day×11days intraperitoneal injection (IP injection) respectively. The remaining 10 rats were housed in group (F) as control group. Control rats received daily injections of 0.9% saline (3ml/kg). As indices of developing neurotoxicity, weight gain, gait scores and landing hindlimb foot splay (LHF) were determined. Weight gains were measured daily prior to injection. Gait scoring involved observation of spontaneous open field locomotion, included evaluations of ataxia, hopping, rearing and hind foot placement, and hindlimb foot splay were determined 3-4 times per week. Gait score was assigned from 1-4. After 11 days, two rats for silver stain, were randomly selected, dissected and proper samples were collected from thoracic portion of the spinal cord of rat. Results did show no neurological behavior in groups A, B and F, whereas severe neurotoxicity was observed in groups C and D. Rats in groups E died within 1-2 hours due to severe toxemia. In histopathological studies based on the de Olmos technique no argyrophilic neurons or processes were observed in stained sections obtained from the thoracic portion of the spinal cord of rats belong to groups A, B and F, while moderate to severe argyrophilic changes were observed in different stained sections obtained from the thoracic portion of the spinal cord of rats belong to groups C and D.

Keywords: acrylamide, rat, axonopathy, argyrophily, de Olmos

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18161 Assessment of the Photovoltaic and Solar Thermal Potential Installation Area on Residential Buildings: Case Study of Amman, Jordan

Authors: Jenan Abu Qadourah

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The suitable surface areas for the ST and PV installation are determined based on incident solar irradiation on different surfaces, shading analysis and suitable architectural area for integration considering limitations due to the constructions, available surfaces area and use of the available surfaces for other purposes. The incident solar radiation on the building surfaces and the building solar exposure analysis of the location of Amman, Jordan, is performed with Autodesk Ecotect analysis 2011 simulation software. The building model geometry within the typical urban context is created in “SketchUp,” which is then imported into Ecotect. The hourly climatic data of Amman, Jordan selected are the same ones used for the building simulation in IDA ICE and Polysun simulation software.

Keywords: photovoltaic, solar thermal, solar incident, simulation, building façade, solar potential

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18160 AgriFood Model in Ankara Regional Innovation Strategy

Authors: Coskun Serefoglu

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The study aims to analyse how a traditional sector such as agri-food could be mobilized through regional innovation strategies. A principal component analysis as well as qualitative information, such as in-depth interviews, focus group and surveys, were employed to find the priority sectors. An agri-food model was developed which includes both a linear model and interactive model. The model consists of two main components, one of which is technological integration and the other one is agricultural extension which is based on Land-grant university approach of U.S. which is not a common practice in Turkey.

Keywords: regional innovation strategy, interactive model, agri-food sector, local development, planning, regional development

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18159 Effect of Electromagnetic Fields at 27 GHz on Sperm Quality of Mytilus galloprovincialis

Authors: Carmen Sica, Elena M. Scalisi, Sara Ignoto, Ludovica Palmeri, Martina Contino, Greta Ferruggia, Antonio Salvaggio, Santi C. Pavone, Gino Sorbello, Loreto Di Donato, Roberta Pecoraro, Maria V. Brundo

Abstract:

Recently, a rise in the use of wireless internet technologies such as Wi-Fi and 5G routers/modems have been demonstrated. These devices emit a considerable amount of electromagnetic radiation (EMR), which could interact with the male reproductive system either by thermal or non-thermal mechanisms. The aim of this study was to investigate the direct in vitro influence of 5G radiation on sperm quality in Mytilus galloprovincialis, considered an excellent model for reproduction studies. The experiments at 27 GHz were conducted by using a no commercial high gain pyramidal horn antenna. To evaluate the specific absorption rate (SAR), a numerical simulation has been performed. The resulting incident power density was significantly lower than the power density limit of 10 mW/cm2 set by the international guidelines as a limit for nonthermal effects above 6 GHz. However, regarding temperature measurements of the aqueous sample, it has been verified an increase of 0.2°C, compared to the control samples. This very low-temperature increase couldn’t interfere with experiments. For experiments, sperm samples taken from sexually mature males of Mytilus galloprovincialis were placed in artificial seawater, salinity 30 + 1% and pH 8.3 filtered with a 0.2 m filter. After evaluating the number and quality of spermatozoa, sperm cells were exposed to electromagnetic fields a 27GHz. The effect of exposure on sperm motility and quality was evaluated after 10, 20, 30 and 40 minutes with a light microscope and also using the Eosin test to verify the vitality of the gametes. All the samples were performed in triplicate and statistical analysis was carried out using one-way analysis of variance (ANOVA) with Turkey test for multiple comparations of means to determine differences of sperm motility. A significant decrease (30%) in sperm motility was observed after 10 minutes of exposure and after 30 minutes, all sperms were immobile and not vital. Due to little literature data about this topic, these results could be useful for further studies concerning a great diffusion of these new technologies.

Keywords: mussel, spermatozoa, sperm motility, millimeter waves

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18158 Mechanistic Structural Insights into the UV Induced Apoptosis via Bcl-2 proteins

Authors: Akash Bera, Suraj Singh, Jacinta Dsouza, Ramakrishna V. Hosur, Pushpa Mishra

Abstract:

Ultraviolet C (UVC) radiation induces apoptosis in mammalian cells and it is suggested that the mechanism by which this occurs is the mitochondrial pathway of apoptosis through the release of cytochrome c from the mitochondria into the cytosol. The Bcl-2 family of proteins pro-and anti-apoptotic is the regulators of the mitochondrial pathway of apoptosis. Upon UVC irradiation, the proliferation of apoptosis is enhanced through the downregulation of the anti-apoptotic protein Bcl-xl and up-regulation of Bax. Although the participation of the Bcl-2 family of proteins in apoptosis appears responsive to UVC radiation, to the author's best knowledge, it is unknown how the structure and, effectively, the function of these proteins are directly impacted by UVC exposure. In this background, we present here a structural rationale for the effect of UVC irradiation in restoring apoptosis using two of the relevant proteins, namely, Bid-FL and Bcl-xl ΔC, whose solution structures have been reported previously. Using a variety of biophysical tools such as circular dichroism, fluorescence and NMR spectroscopy, we show that following UVC irradiation, the structures of Bcl-xlΔC and Bid-FL are irreversibly altered. Bcl-xLΔC is found to be more sensitive to UV exposure than Bid-FL. From the NMR data, dramatic structural perturbations (α-helix to β-sheet) are seen to occur in the BH3 binding region, a crucial segment of Bcl-xlΔC which impacts the efficacy of its interactions with pro-apoptotic tBid. These results explain the regulation of apoptosis by UVC irradiation. Our results on irradiation dosage dependence of the structural changes have therapeutic potential for the treatment of cancer.

Keywords: Bid, Bcl-xl, UVC, apoptosis

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18157 Effect of Inoculum Ratio on Dark Fermentative Hydrogen Production

Authors: Zeynep Yilmazer Hitit, Patrick C. Hallenbeck

Abstract:

Fuel reserve requirements due to depletion of fossil fuels have increased interest in biohydrogen since the 1990’s. In fermentative hydrogen production, pure, mixed, and co-cultures can be used to produce hydrogen. Several previous studies have evaluated hydrogen production by pure cultures of Clostridium butyricum or Enterobacter aerogenes. Evaluating hydrogen production by co-culture of these microorganisms is an interestıng approach since E. aerogenes is a facultative microorganism with resistance to oxygen in contrast to the strict anaerobe C. butyricum, and therefore has the ability to maintain anaerobic conditions. It was found that using co-cultures of facultative E. aerogenes (as a reducing agent and H2 producer) and the obligate anaerobe C. butyricum for producing hydrogen increases the yield of hydrogen by about 50% compared to C. butyricum by itself. Also, using different types of microorganisms for hydrogen production eliminates the need to use expensive reducing agents. C. butyricum strain pre-cultured anaerobically at 37 0C for 15h by inoculating 100 mL of GP medium (pH 6.8) consisting of 1% glucose, 2% polypeptone, 0.2% KH2PO4, 0.05% yeast extract, 0.05% MgSO4. 7H2O and E. aerogenes strain was pre-cultured aerobically at 30 0C, 150 rpm for 9 h by inoculating 100 mL of TGY medium (pH 6.8), consisting of 0.1% glucose, 0.5% tryptone, 0.1% K2HPO4, 0.5% yeast extract. All duplicate batch experiments were conducted in 100 mL bottles with different inoculum ratios of Clostridium butyricum and Enterobater aerogenes (C:E) using 5x diluted rich media (GP) consisting of 2 g/L glucose, 4g/L polypeptone, 0.4 g/L KH2PO4, 0.1 g/L yeast extract, 0.1 MgSO4.7H2O. The range of inoculum ratio of C. butyricum to E. aerogenes were 2:1,4:1,8:1, 1:2,1:4, 1:8, 1:0, 0:1. Using glucose as a carbon source aided in the observation of microbial behavior as well as making the effect of inoculum ratio more evident. Nearly all the glucose in the medium was used to produce hydrogen, except at a 1:0 ratio of inoculum (i.e. containing only C. butyricum). Low glucose consumption leads to a higher hydrogen yield due to cumulative hydrogen production and consumption of glucose, but not as much as C:E, 8:1. The lowest hydrogen yield was achieved in 1:8 inoculum ratio of C:E, 71.9 mL, 1.007±0.01 mol H2/mol glucose and the highest cumulative hydrogen, hydrogen yield and dry cell weight were achieved in 8:1 inoculum ratio of C:E, 117.4 mL, 2.035±0.082 mol H2/mol glucose, 0.4 g/L respectively. In this study effect of inoculum ratio on dark fermentative biohydrogen production using C. butyricum and E. aerogenes was investigated. The maximum hydrogen yield of 2.035mol H2/mol glucose was obtained using 2g/L glucose, an initial pH of 6 and an inoculum ratio of C. butyricum to E. aerogenes of 8:1. Results showed that inoculum ratio is an important parameter on hydrogen production due to competition between the two microorganisms in using substrate for growth and production of by-products. The results presented here could be of great significance for further waste management studies using co-culture hydrogen production.

Keywords: biohydrogen, Clostridium butyricum, dark fermentation, Enterobacter aerogenes, inoculum ratio in biohydrogen production

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18156 Applying the Underwriting Technique to Analyze and Mitigate the Credit Risks in Construction Project Management

Authors: Hai Chien Pham, Thi Phuong Anh Vo, Chansik Park

Abstract:

Risks management in construction projects is important to ensure the positive feasibility of the projects in which financial risks are most concerned while construction projects always run on a credit basis. Credit risks, therefore, require unique and technical tools to be well managed. Underwriting technique in credit risks, in its most basic sense, refers to the process of evaluating the risks and the potential exposure of losses. Risks analysis and underwriting are applied as a must in banks and financial institutions who are supporters for constructions projects when required. Recently, construction organizations, especially contractors, have recognized the significant increasing of credit risks which caused negative impacts to project performance and profit of construction firms. Despite the successful application of underwriting in banks and financial institutions for many years, there are few contractors who are applying this technique to analyze and mitigate the credit risks of their potential owners before signing contracts with them for delivering their performed services. Thus, contractors have taken credit risks during project implementation which might be not materialized due to the bankruptcy and/or protracted default made by their owners. With this regard, this study proposes a model using the underwriting technique for contractors to analyze and assess credit risks of their owners before making final decisions for the potential construction contracts. Contractor’s underwriters are able to analyze and evaluate the subjects such as owner, country, sector, payment terms, financial figures and their related concerns of the credit limit requests in details based on reliable information sources, and then input into the proposed model to have the Overall Assessment Score (OAS). The OAS is as a benchmark for the decision makers to grant the proper limits for the project. The proposed underwriting model is validated by 30 subjects in Asia Pacific region within 5 years to achieve their OAS, and then compare output OAS with their own practical performance in order to evaluate the potential of underwriting model for analyzing and assessing credit risks. The results revealed that the underwriting would be a powerful method to assist contractors in making precise decisions. The contribution of this research is to allow the contractors firstly to develop their own credit risk management model for proactively preventing the credit risks of construction projects and continuously improve and enhance the performance of this function during project implementation.

Keywords: underwriting technique, credit risk, risk management, construction project

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18155 Stability Analysis of SEIR Epidemic Model with Treatment Function

Authors: Sasiporn Rattanasupha, Settapat Chinviriyasit

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The treatment function adopts a continuous and differentiable function which can describe the effect of delayed treatment when the number of infected individuals increases and the medical condition is limited. In this paper, the SEIR epidemic model with treatment function is studied to investigate the dynamics of the model due to the effect of treatment. It is assumed that the treatment rate is proportional to the number of infective patients. The stability of the model is analyzed. The model is simulated to illustrate the analytical results and to investigate the effects of treatment on the spread of infection.

Keywords: basic reproduction number, local stability, SEIR epidemic model, treatment function

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18154 Prevalence of Rituximab Efficacy Over Immunosuppressants in Therapy of Systemic Sclerosis

Authors: Liudmila Garzanova, Lidia Ananyeva, Olga Koneva, Olga Ovsyannikova, Oxana Desinova, Mayya Starovoytova, Rushana Shayahmetova, Anna Khelkovskaya-Sergeeva

Abstract:

Abstract Objectives. Rituximab (RTX) shown a positive effect in the treatment of systemic sclerosis (SSc). But there is still not enough data on comparing the effectiveness of RTX with immunosuppressants (IS). The aim of our study was to compare changes of lung function and skin score in SSc between two groups of patients (pts) - on RXT therapy (prescribed after ineffectiveness of previous therapy with IS) and on therapy with IS only. Methods. This study included 103 pts received RTX as an addition to previous therapy (group 1) and 65 pts received therapy with IS and prednisolone (group 2). The mean follow-up period was 12.6±10.7months. In group 1 the mean age was 47±12.9 years, female – 88 pts (84%), the diffuse cutaneous subset of the disease had 55 pts (53%). The mean disease duration was 6.2±5.5 years. 82% pts had interstitial lung disease (ILD) and 92% were positive for ANA, 67% of them were positive for antitopoisomerase-1. All pts received prednisolone at a dose of 11.3±4.5 mg/day, IS at inclusion received 47% of them. The cumulative mean dose of RTX was 1.7±0.6 g. In group 2 the mean age was 50.8±13.8 years, female-53 pts (82%), the diffuse cutaneous subset of the disease had 44 pts (68%). The mean disease duration was 8.8±7.7 years. 81% pts had ILD and 88% were positive for ANA, 58% of them were positive for antitopoisomerase-1. All pts received prednisolone at a dose of 8.69±4.28 mg/day, IS received 57% of them. Cyclophosphamide (CP) received 45% of pts. The cumulative mean dose of CP was 10.2±15.1g. D-penicillamine received 30% of pts. Other pts was on mycophenolate mofetil or methotrexate therapy in single cases. The pts of the compared groups did not differ in the main demographic and clinical parameters. The results are presented as delta (Δ) - difference between the baseline parameter and follow up point. Results. In group 1 there was an improvement of all outcome parameters: increased of forced vital capacity, % predicted - ΔFVC=4% (p=0.0004); Diffusing capacity for carbon monoxide, % predicted remained stable (ΔDLCO=0.1%); improvement of the Rodnan skin score-ΔmRss=3.4 (p=0.001); decrease of Activity index (EScSG-AI) - ΔActivity index=1.7 (p=0.001). In group 2 the changes was insignificant: ΔFVC=-2.3%, ΔmRss=0.87, ΔActivity index=0.3. But there was a significant decrease of DLCO: ΔDLCO=-5.1% (p=0.001). Conclusion. The results of our study confirm the data on the positive effect of RTX in complex therapy in pts with SSc (decrease of skin induration, increase of FVC, stabilization of DLCO). Meantime, pts on IS and prednisolone therapy shown the worsening of lung function and insignificant changes of other clinical parameters. RTX could be considered as a more effective option in complex treatment of SSc in comparison with IS therapy

Keywords: immunosuppressants, interstitial lung disease, systemic sclerosis, rituximab

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18153 Synthesis of NiO and ZnO Nanoparticles and Charactiration for the Eradication of Lead (Pb) from Wastewater

Authors: Sadia Ata, Anila Tabassum, Samina ghafoor, Ijaz ul Mohsin, Azam Muktar

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Heavy metal ions such as Pb2+, Cd2+, Zn2+, Ni2+ and Hg2+, in wastewater are considered as the serious environmental problem. Among these heavy metals, Lead or Pb (II) is the most toxic heavy metal. Exposure to lead causes damage of nervous system, mental retardation, renal kidney disease, anemia and cancer in human beings. Adsorption is the most widely used method to remove metal ions based on the physical interaction between metal ions and sorbents. With the development of nanotechnology, nano-sized materials are proved to be effective sorbents for the removal of heavy metal ions from wastewater due to their unique structural properties. The present work mainly focuses on the synthesis of NiO and ZnO nanoparticles for the removal of Lead ions, their preparation, characterization by XRD, FTIR, SEM, and TEM, adsorption characteristics and mechanism, along with adsorption isotherm model and adsorption kinetics to understand the adsorption procedure.

Keywords: heavy metal, adsorption isotherms, nanoparticles, wastewater

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18152 Assessment of Genotoxic Effects of a Fungicide (Propiconazole) in Freshwater Fish Gambusia Affinis Using Alkaline Single-Cell Gel Electrophoresis (Comet Essay)

Authors: Bourenane Bouhafs Naziha

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ARTEA330EC is a fungicide used to inhibit the growth of many types of fungi on and cereals and rice, it is the single largest selling agrochemical that has been widely detected in surface waters in our area (Northeast Algerian). The studies on long-term genotoxic effects of fugicides in different tissues of fish using genotoxic biomarkers are limited. Therefore, in the present study DNA damage by propiconazole in freshwater fish Gambusia affinis by comet assays was investigated. The LC(50)- 96 h of the fungicide was estimated for the fish in a semi-static system. On this basis of LC(50) value sublethal and nonlethal concentrations were determined (25; 50; 75; and 100 ppm). The DNA damage was measured in erythrocytes as the percentage of DNA in comet tails of fishes exposed to above concentrations the fungicide. In general,non significant effects for both the concentrations and time of exposure were observed in treated fish compared with the controls. However It was found that the highest DNA damage was observed at the highest concentration and the longest time of exposure (day 12). The study indicated comet assay to be sensitive and rapid method to detect genotoxicity of propiconasol and other pesticides in fishes.

Keywords: genotoxicity, fungicide, propiconazole, freshwater, Gambusia affinis, alkaline single-cell gel electrophoresis

Procedia PDF Downloads 298