Search results for: media studies
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 13518

Search results for: media studies

4008 Shortening Distances: The Link between Logistics and International Trade

Authors: Felipe Bedoya Maya, Agustina Calatayud, Vileydy Gonzalez Mejia

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Encompassing inventory, warehousing, and transportation management, logistics is a crucial predictor of firm performance. This has been extensively proven by extant literature in business and operations management. Logistics is also a fundamental determinant of a country's ability to access international markets. Available studies in international and transport economics have shown that limited transport infrastructure and underperforming transport services can severely affect international competitiveness. However, the evidence lacks the overall impact of logistics performance-encompassing all inventory, warehousing, and transport components- on global trade. In order to fill this knowledge gap, the paper uses a gravitational trade model with 155 countries from all geographical regions between 2007 and 2018. Data on logistics performance is obtained from the World Bank's Logistics Performance Index (LPI). First, the relationship between logistics performance and a country’s total trade is estimated, followed by a breakdown by the economic sector. Then, the analysis is disaggregated according to the level of technological intensity of traded goods. Finally, after evaluating the intensive margin of trade, the relevance of logistics infrastructure and services for the extensive trade margin is assessed. Results suggest that: (i) improvements in both logistics infrastructure and services are associated with export growth; (ii) manufactured goods can significantly benefit from these improvements, especially when both exporting and importing countries increase their logistics performance; (iii) the quality of logistics infrastructure and services becomes more important as traded goods are technology-intensive; and (iv) improving the exporting country's logistics performance is essential in the intensive margin of trade while enhancing the importing country's logistics performance is more relevant in the extensive margin.

Keywords: gravity models, infrastructure, international trade, logistics

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4007 The Synthesis, Structure and Catalytic Activity of Iron(II) Complex with New N2O2 Donor Schiff Base Ligand

Authors: Neslihan Beyazit, Sahin Bayraktar, Cahit Demetgul

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Transition metal ions have an important role in biochemistry and biomimetic systems and may provide the basis of models for active sites of biological targets. The presence of copper(II), iron(II) and zinc(II) is crucial in many biological processes. Tetradentate N2O2 donor Schiff base ligands are well known to form stable transition metal complexes and these complexes have also applications in clinical and analytical fields. In this study, we present salient structural features and the details of cathecholase activity of Fe(II) complex of a new Schiff Base ligand. A new asymmetrical N2O2 donor Schiff base ligand and its Fe(II) complex were synthesized by condensation of 4-nitro-1,2 phenylenediamine with 6-formyl-7-hydroxy-5-methoxy-2-methylbenzopyran-4-one and by using an appropriate Fe(II) salt, respectively. Schiff base ligand and its metal complex were characterized by using FT-IR, 1H NMR, 13C NMR, UV-Vis, elemental analysis and magnetic susceptibility. In order to determine the kinetics parameters of catechol oxidase-like activity of Schiff base Fe(II) complex, the oxidation of the 3,5-di-tert-butylcatechol (3,5-DTBC) was measured at 25°C by monitoring the increase of the absorption band at 390-400 nm of the product 3,5-di-tert-butylcatequinone (3,5-DTBQ). The compatibility of catalytic reaction with Michaelis-Menten kinetics also investigated by the method of initial rates by monitoring the growth of the 390–400 nm band of 3,5-DTBQ as a function of time. Kinetic studies showed that Fe(II) complex of the new N2O2 donor Schiff base ligand was capable of acting as a model compound for simulating the catecholase properties of type-3 copper proteins.

Keywords: catecholase activity, Michaelis-Menten kinetics, Schiff base, transition metals

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4006 Behavioural Studies on Multidirectional Reinforced 4-D Orthogonal Composites on Various Preform Configurations

Authors: Sriram Venkatesh, V. Murali Mohan, T. V. Karthikeyan

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The main advantage of multi-directionally reinforced composites is the freedom to orient selected fibre types and hence derives the benefits of varying fibre volume fractions and there by accommodate the design loads of the final structure of composites. This technology provides the means to produce tailored composites with desired properties. Due to the high level of fibre integrity with through thickness reinforcement those composites are expected to exhibit superior load bearing characteristics with capability to carry load even after noticeable and apparent fracture. However a survey of published literature indicates inadequacy in the design and test data base for the complete characterization of the multidirectional composites. In this paper the research objective is focused on the development and testing of 4-D orthogonal composites with different preform configurations and resin systems. A preform is the skeleton 4D reinforced composite other than the matrix. In 4-D preforms fibre bundles are oriented in three directions at 1200 with respect to each other and they are on orthogonal plane with the fibre in 4th direction. This paper addresses the various types of 4-D composite manufacturing processes and the mechanical test methods followed for the material characterization. A composite analysis is also made, experiments on course and fine woven preforms are conducted and the findings of test results are discussed in this paper. The interpretations of the test results reveal several useful and interesting features. This should pave the way for more widespread use of the perform configurations for allied applications.

Keywords: multi-directionally reinforced composites, 4-D orthogonal preform, course weave, fine weave, fibre bundle spools, unit cell, fibre architecture, fibre volume fraction, fibre distribution

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4005 Determining Factors for Successful Blended Learning in Higher Education: A Qualitative Study

Authors: Pia Wetzl

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The learning process of students can be optimized by combining online teaching with face-to-face sessions. So-called blended learning offers extensive flexibility as well as contact opportunities with fellow students and teachers. Furthermore, learning can be individualized and self-regulated. The aim of this article is to investigate which factors are necessary for blended learning to be successful. Semi-structured interviews were conducted with students (N = 60) and lecturers (N = 21) from different disciplines at two German universities. The questions focused on the perception of online, face-to-face and blended learning courses. In addition, questions focused on possible optimization potential and obstacles to practical implementation. The results show that on-site presence is very important for blended learning to be successful. If students do not get to know each other on-site, there is a risk of loneliness during the self-learning phases. This has a negative impact on motivation. From the perspective of the lecturers, the willingness of the students to participate in the sessions on-site is low. Especially when there is no obligation to attend, group work is difficult to implement because the number of students attending is too low. Lecturers would like to see more opportunities from the university and its administration to enforce attendance. In their view, this is the only way to ensure the success of blended learning. In addition, they see the conception of blended learning courses as requiring a great deal of time, which they are not always willing to invest. More incentives are necessary to keep the lecturers motivated to develop engaging teaching material. The study identifies factors that can help teachers conceptualize blended learning. It also provides specific implementation advice and identifies potential impacts. This catalogue has great value for the future-oriented development of courses at universities. Future studies could test its practical use.

Keywords: blended learning, higher education, teachers, student learning, qualitative research

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4004 The Paleoenvironment and Paleoclimatological Variations during Aptian in North Central Tunisia

Authors: Houda Khaled, Frederic Boulvain, Fredj Chaabani

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This paper focuses on the sedimentological and mineralogical studies of Aptian series outcrops in the Serdj and Bellouta Mountain situated in north-central Tunisia. In the Serdj Mountain, the Aptian series is about 590 meters thick and it is defined by tow formations corresponding respectively to the Sidi Hamada formation (Barremian-Gragasian) and the Serdj formation (Middle Gragasian-Late Clansaysian). This later is consisting of five limestones sequences separated by marly levels limestones associated to some siltstones bed. The Bellouta section is especially composed of carbonate rocks and it is attributed to the Middle Gragasian - Late Clansaysian. These sections are studied in detail regarding lithology, micropaleontology, microfacies, magnetic susceptibility and mineralogical composition in order to provide new insights into the paleoenvironmental evolution and paleoclimatological implications during Aptian. The following facies associations representing different ramp palaeoenvironments have been identified: mudstone-wackestone outer ramp facies; skeletal grainstone-packstone mid-ramp facies, packstone-grainstone inner-ramp facies which include a variety of organisms such as ooliths, rudists ostracods associated to athor bioclats. The coastal facies is especially defined by a mudstone -wackestone texture coastal rich with miliolidea and orbitolines. The magnetic susceptibility (Xin) of all samples was compared with the lithological and microfacies variation. The MS curves show that the high values are correlated with the distal facies and the low values are registred in the coastal environment. The X-ray diffractometer analysis show the presence of kaolinite and illite.

Keywords: Aptian, Serdj formation, mineralogy, petrography

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4003 Cigarette Smoking and Alcohol Use among Mauritian Adolescents: Analysis of 2017 WHO Global School-Based Student Health Survey

Authors: Iyanujesu Adereti, Tajudeen Basiru, Ayodamola Olanipekun

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Background: Substance abuse among adolescents is of public health concern globally. Despite being the most abused by adolescents, there are limited studies on the prevalence of alcohol use and cigarette smoking among adolescents in Mauritius. Objectives: To determine the prevalence of cigarette smoking, alcohol use and associated correlates among school-going adolescents in Mauritius. Methodology: Data obtained from 2017 WHO Global School-based Student Health Survey (GSHS) survey of 3,012 school-going adolescents in Mauritius was analyzed using STATA. Descriptive statistics were used to obtain prevalence. Bivariate and multivariate logistic regression analysis was used to evaluate predictors of cigarette smoking and alcohol use. Results: Prevalence of alcohol consumption and cigarette smoking were 26.0% and 17.1%, respectively. Smoking and alcohol use was more prevalent among males, younger adolescents, and those in higher school grades (p-value <.000). In multivariable logistic regression, male gender was associated with a higher risk of cigarette smoking (adjusted Odds Ratio (aOR) [95%Confidence Interval (CI)]= 1.51[1.06-2.14]) but lower risk of alcohol use (aOR[95%CI]= 0.69[0.53-0.90]) while older age (mid and late adolescence) and parental smoking were found to be associated with increased risk of alcohol use (aOR[95%CI]= 1.94[1.34-2.99] and 1.36[1.05-1.78] respectively). Marijuana use, truancy, being in a fight and suicide ideation were associated with increased odds of alcohol use (aOR[95%CI]= 3.82[3.39-6.09]; 2.15[1.62-2.87]; 1.83[1.34-2.49] and 1.93[1.38-2.69] respectively) and cigarette smoking (aOR[95%CI]= 17.28[10.4 - 28.51]; 1.73[1.21-2. 49]; 1.67[1.14-2.45] and 2.17[1.43-3.28] respectively) while involvement in sexual activity was associated with reduced risk of alcohol use (aOR[95%CI]= 0.50[0.37-0.68]) and cigarette smoking (aOR[95%CI]= 0.47[0.33-0.69]). Parental support and parental monitoring were uniquely associated with lower risk of cigarette smoking (aOR[95%CI]= 0.69[0.47-0.99] and 0.62[0.43-0.91] respectively). Conclusion: The high prevalence of alcohol use and cigarette smoking in this study shows the need for the government of Mauritius to enhance policies that will help address this issue putting into accounts the various risk and protective factors.

Keywords: adolescent health, alcohol use, cigarette smoking, global school-based student health survey

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4002 Into Composer’s Mind: Understanding the Process of Translating Emotions into Music

Authors: Sanam Preet Singh

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Music in comparison to any other art form is more reactive and alive. It has the capacity to directly interact with the listener's mind and generate an emotional response. All the major research conducted in the area majorly relied on the listener’s perspective to draw an understanding of music and its effects. There is a very small number of studies which focused on the source from which music originates, the music composers. This study aims to understand the process of how music composers understand and perceive emotions and how they translate them into music, in simpler terms how music composers encode their compositions to express determining emotions. One-to-one in-depth semi structured interviews were conducted, with 8 individuals both male and female, who were professional to intermediate-level music composers and Thematic analysis was conducted to derive the themes. The analysis showed that there is no single process on which music composers rely, rather there are combinations of multiple micro processes, which constitute the understanding and translation of emotions into music. In terms of perception of emotions, the role of processes such as Rumination, mood influence and escapism was discovered in the analysis. Unique themes about the understanding of their top down and bottom up perceptions were also discovered. Further analysis also revealed the role of imagination and emotional trigger explaining how music composers make sense of emotions. The translation process of emotions revealed the role of articulation and instrumentalization, in encoding or translating emotions to a composition. Further, applications of the trial and error method, nature influences and flow in the translation process are also discussed. In the end themes such as parallels between musical patterns and emotions, comfort zones and relatability also emerged during the analysis.

Keywords: comfort zones, escapism, flow, rumination

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4001 Appropriation of Cryptocurrencies as a Payment Method by South African Retailers

Authors: Neliswa Dyosi

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Purpose - Using an integrated Technology-Organization-Environment (TOE) framework and the model of technology appropriation (MTA) as a theoretical lens, this interpretive qualitative study seeks to understand and explain the factors that influence the appropriation, non-appropriation, and disappropriation of bitcoin as a payment method by South African retailers. Design/methodology/approach –The study adopts the interpretivist philosophical paradigm. Multiple case studies will be adopted as a research strategy. For data collection, the study follows a qualitative approach. Qualitative data will be collected from the six retailers in various industries. Semi-structured interviews and documents will be used as the data collection techniques. Purposive and snowballing sampling techniques will be used to identify participants within the organizations. Data will be analyzed using thematic analysis. Originality/value - Using the deduction approach, the study seeks to provide a descriptive and explanatory contribution to theory. The study contributes to theory development by integrating the MTA and TOE frameworks as a means to understand technology adoption behaviors of organizations, in this case, retailers. This is also the first study that looks at an integrated approach of the Technology-Organization-Environment (TOE) framework and the MTA framework to understand the adoption and use of a payment method. South Africa is ranked amongst the top ten countries in the world on cryptocurrency adoption. There is, however, still a dearth of literature on the current state of adoption and usage of bitcoin as a payment method in South Africa. The study will contribute to the existing literature as bitcoin cryptocurrency is gaining popularity as an alternative payment method across the globe.

Keywords: cryptocurrency, bitcoin, payment methods, blockchain, appropriation, online retailers, TOE framework, disappropriation, non-appropriation

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4000 Need for E-Learning: An Effective Method in Educating the Persons with Hearing Impairment Using Sign Language

Authors: S. Vijayakumar, S. B. Rathna Kumar, Navnath D Jagadale

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Learning and teaching are the challenges ahead in the education of the students with hearing impairment using sign language (SHISL). Either the students or teachers face difficulties in the process of learning/teaching. Communication is one of the main barriers while teaching SHISL. Further, the courses of study or the subjects are limited to SHISL at least in countries like India. Students with hearing impairment mainly opt for sign language as a communication mode. Subjects like physics, chemistry, advanced mathematics etc. are not available in the curriculum for the SHISL since their content and ideas are complex. In India, exemption for language papers is being given for the students with hearing impairment. It may give opportunity to them to secure secondary/ higher secondary qualifications. It is a known fact that students with hearing impairment are facing difficulty in their future carrier. They secure neither a higher study nor a good employment opportunity. Vocational training in various trades will land them in few jobs with few bucks in pocket. However, not all of them are blessed with higher positions in government or private sectors in competitive fields or where the technical knowledge is required. E learning with sign language instructions can be used for teaching languages and science subjects. Computer Based Instruction (CBI), Computer Based Training (CBT), and Computer Assisted Instruction (CAI) are now part-and-parcel of Modern Education. It will also include signed video clip corresponding to the topic. Learning language subjects will improve the understanding of concepts in different subjects. Learning other science subjects like their hearing counterparts will enable the SHISL to go higher in studies and increase their height to pluck a fruit of the tree of employment.

Keywords: students with hearing impairment using sign language, hearing impairment, language subjects, science subjects, e-learning

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3999 A Conceptual Framework and a Mathematical Equation for Managing Construction-Material Waste and Cost Overruns

Authors: Saidu Ibrahim, Winston M. W. Shakantu

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The problem of construction material waste remains unresolved, as a significant percentage of the materials delivered to some project sites end up as waste which might result in additional project cost. Cost overrun is a problem which affects 90% of the completed projects in the world. The argument on how to eliminate it has been on-going for the past 70 years, but there is neither substantial improvement nor significant solution for mitigating its detrimental effects. Research evidence has proposed various construction cost overruns and material-waste management approaches; nonetheless, these studies failed to give a clear indication on the framework and the equation for managing construction material waste and cost overruns. Hence, this research aims to develop a conceptual framework and a mathematical equation for managing material waste and cost overrun in the construction industry. The paper adopts the desktop methodological approach. This involves comparing the causes of material waste and those of cost overruns from the literature to determine the possible relationship. The review revealed a relationship between material waste and cost overrun that; increase in material waste would result to a corresponding increase in the amount of cost overrun at both the pre-contract and the post contract stages of a project. It was found from the equation that achieving an effective construction material waste management must ensure a “Good Quality-of-Planning, Estimating, and Design Management” and a “Good Quality- of-Construction, Procurement and Site Management”; a decrease in “Design Complexity” which would reduce “Material Waste” and subsequently reduce the amount of cost overrun by 86.74%. The conceptual framework and the mathematical equation developed in this study are recommended to the professionals of the construction industry.

Keywords: conceptual framework, cost overrun, material waste, project stags

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3998 Influencing Factors to Mandatory versus Non-Mandatory E-Government Services Adoption in India: An Empirical Study

Authors: Rajiv Kumar, Amit Sachan, Arindam Mukherjee

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Government agencies around the world, including India, are incorporating digital technologies and processes into their day-to-day operations to become more efficient. Despite low internet penetration (around 34.8% of total population) in India, Government of India has made some public services mandatory to access online (e.g. passport, tax filing).This is insisting citizens to access mandatory public services online. However, due to digital divide, all citizens do not have equal access to internet. In light of this, it is an interesting topic to explore how citizens are able to access mandatory online public services. It is important to understand how citizens are adopting these mandatory e-government services and how the adoption behavior of these mandatory e-government services is different or similar to adoption behavior of non-mandatory e-government services. The purpose of this research is to investigate the factors that influence adoption of mandatory and non-mandatory e-government services in India. A quantitative technique is employed in this study. A conceptual model has been proposed by integrating the influencing factors to adopt e-government services from previous studies. The proposed conceptual model highlights a comprehensive set of potential factors influencing the adoption of e-government services. The proposed model has been validated by keeping in view the local context of Indian society. Online and paper based survey was administered, collected data was analyzed and results have been discussed. A total of 463 valid responses were received and further the responses were analyzed. The research reveals that the influencing factors to adopt e-government services are not same for both mandatory and non-mandatory e-government services. There are some factors that influence adoption of both mandatory and non-mandatory e-government services but there are some which are relevant for either of mandatory and non-mandatory e-government services. The research findings may help government or concerned agencies in successfully implementing e-government services.

Keywords: adoption, e-government, India, mandatory, non-mandatory

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3997 The Effect of Neurocognitive Exercise Program on ADHD Symptoms, Attention, and Dynamic Balance in Medication Naive Children with ADHD: A Pilot Study

Authors: Nurullah Buker, Ezgi Karagoz, Yesim Salik Sengul, Sevay Alsen Guney, Gokhan Yoyler, Aylin Ozbek

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Attention Deficit Hyperactivity Disorder (ADHD) is one of the most common neurodevelopmental disorders with heterogeneous clinical features such as inattention, hyperactivity, and impulsivity. Many different types of exercise interventions were employed for children with ADHD. However, previous studies have usually examined the effects of non-specific exercise programs or short-term effects of exercise. The aim of this study is to investigate the effect of the Neurocognitive Exercise Program (NEP), which is a structured exercise program derived from Life Kinetik, and a relatively new for children with ADHD, on symptoms, attention, and dynamic balance in medication-naïve children with ADHD. Fourteen medication-naive children (7-12 years) with ADHD were included in the intervention group. NEP was performed once a week for ten weeks. The intervention group also performed a structured home exercise program for another six days, for ten weeks. The children in the intervention group were assessed at baseline, in the third month, in the sixth month, and in the twelfth month regarding ADHD-related symptoms, attention, and dynamic balance. Fifteen age-matched typically developing children were assessed once for establishing normative values. Hyperactivity-Impulsivity score and dynamic balance were found to improve after NEP in the ADHD group in the 3rd month (p<0.05). In addition, these results were similar for both groups after NEP and at the end of the 12th month (p>0.05). The NEP may provide beneficial effects on hyperactivity-impulsivity, oppositional defiant, and dynamic balance in children with ADHD, and the improvements may be maintained in the long term.

Keywords: ADHD, attention problems, dynamic balance, neurocognitive exercise

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3996 Increasing Solubility and Bioavailability of Fluvastatin through Transdermal Nanoemulsion Gel Delivery System for the Treatment of Osteoporosis

Authors: Ramandeep Kaur, Makula Ajitha

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Fluvastatin has been reported for increasing bone mineral density in osteoporosis since last decade. Systemically administered drug undergoes extensive hepatic first-pass metabolism, thus very small amount of drug reaches the bone tissue which is highly insignificant. The present study aims to deliver fluvastatin in the form of nanoemulsion (NE) gel directly to the bone tissue through transdermal route thereby bypassing hepatic first pass metabolism. The NE formulation consisted of isopropyl myristate as oil, tween 80 as surfactant, transcutol as co-surfactant and water as the aqueous phase. Pseudoternary phase diagrams were constructed using aqueous titration method and NE’s obtained were subjected to thermodynamic-kinetic stability studies. The stable NE formulations were evaluated for their droplet size, zeta potential, and transmission electron microscopy (TEM). The nano-sized formulations were incorporated into 0.5% carbopol 934 gel matrix. Ex-vivo permeation behaviour of selected formulations through rat skin was investigated and compared with the conventional formulations (suspension and emulsion). Further, in-vivo pharmacokinetic study was carried using male Wistar rats. The optimized NE formulations mean droplet size was 11.66±3.2 nm with polydispersity index of 0.117. Permeation flux of NE gel formulations was found significantly higher than the conventional formulations i.e. suspension and emulsion. In vivo pharmacokinetic study showed significant increase in bioavailability (1.25 fold) of fluvastatin than oral formulation. Thus, it can be concluded that NE gel was successfully developed for transdermal delivery of fluvastatin for the treatment of osteoporosis.

Keywords: fluvastatin, nanoemulsion gel, osteoporosis, transdermal

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3995 An Initial Evaluation of Newly Proposed Biomarker of Zinc Status in Humans: The Erythrocyte Linoleic Acid: Dihomo-γ-Linolenic Acid (LA:DGLA) Ratio

Authors: Marija Knez, James C.R. Stangoulis, Manja Zec, Zoran Pavlovic, Jasmina D. Martacic, Mirjana Gurinovic, Maria Glibetic

Abstract:

Background: Zinc is an essential micronutrient for humans with important physiological functions. A sensitive and specific biomarker for assessing Zn status is still needed. Objective: The major aim of this study was to examine if the changes in the content of plasma phospholipid LA, DGLA and LA: DGLA ratio can be used to efficiently predict the dietary Zn intake and plasma Zn status of humans. Methods: The study was performed on apparently healthy human volunteers. The dietary Zn intake was assessed using 24h recall questionnaires. Plasma phospholipid fatty acid analysis was done by gas chromatography and plasma analysis of minerals by atomic absorption spectrometry. Biochemical, anthropometrical and hematological parameters were assessed. Results: No significant relationship was found between the dietary and plasma zinc status (r=0.07; p=0.6). There is a statistically significant correlation between DGLA and plasma Zn (r=0.39, p=0.00). No relationship was observed between the linoleic acid and plasma Zn, while there was a significant negative correlation between LA: DGLA ratio and plasma Zn status (r=-0.35, p=0.01). Similarly, there were statistically significant difference in DGLA status (p=0.004) and LA: DGLA ratio (p=0.042) between the Zn formed groups. Conclusions: This study is an initial step in evaluating LA: DGLA ratio as a biomarker of Zn status in humans. The results are encouraging as they show that concentration of DGLA is decreased and LA: DGLA ratio increased in people with lower dietary Zn intake. However, additional studies are needed to fully examine the sensitivity of this biomarker.

Keywords: dietary Zn intake Zinc, fatty acid composition, LA: DGLA, healthy population, plasma Zn status, Zn biomarker

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3994 Framework for the Assessment of National Systems of Innovation in Biotechnology

Authors: Andrea Schiffauerova, Amnah Alzeyoudi

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This paper studies patterns of innovation within national constitutional context. Its objective is to examine national systems of innovation in biotechnology in six leading innovative countries: the US, Japan, Germany, the UK, France and Canada. The framework proposed for this purpose consists of specific factors considered critical for the development of national systems of innovation, which are industry size, innovative activities, area of specialization, industry structure, national policy, the level of government intervention, the stock of knowledge in universities and industries, knowledge transfer from universities to industry and country-specific conditions for start-ups. The paper then uses the framework to provide detailed cross-country comparisons while highlighting particular features of national institutional context which affect the creation and diffusion of scientific knowledge within the system. The study is primarily based on the extensive survey of literature and it is complemented by the quantitative analysis of the patent data extracted from the United States Patent and Trademark Office (USPTO). The empirical analysis provides numerous insights and greatly complements the data gained from the literature and other sources. The final cross-country comparative analysis identifies three patterns followed by the national innovation systems in the six countries. The proposed cross-country relative positioning analysis may help in drawing policy implications and strategies leading to the enhancement of national competitive advantage and innovation capabilities of nations.

Keywords: comparative analysis, framework, national systems of innovation, patent analysis, United States Patent and Trademark Office (USPTO)

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3993 Magnetic Cellulase/Halloysite Nanotubes as Biocatalytic System for Converting Agro-Waste into Value-Added Product

Authors: Devendra Sillu, Shekhar Agnihotri

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The 'nano-biocatalyst' utilizes an ordered assembling of enzyme on to nanomaterial carriers to catalyze desirable biochemical kinetics and substrate selectivity. The current study describes an inter-disciplinary approach for converting agriculture waste, sugarcane bagasse into D-glucose exploiting halloysite nanotubes (HNTs) decorated cellulase enzyme as nano-biocatalytic system. Cellulase was successfully immobilized on HNTs employing polydopamine as an eco-friendly crosslinker while iron oxide nanoparticles were attached to facilitate magnetic recovery of material. The characterization studies (UV-Vis, TEM, SEM, and XRD) displayed the characteristic features of both cellulase and magnetic HNTs in the resulting nanocomposite. Various factors (i.e., working pH, temp., crosslinker conc., enzyme conc.) which may influence the activity of biocatalytic system were investigated. The experimental design was performed using Response Surface Methodology (RSM) for process optimization. Analyses data demonstrated that the nanobiocatalysts retained 80.30% activity even at elevated temperature (55°C) and excellent storage stabilities after 10 days. The repeated usage of system revealed a remarkable consistent relative activity over several cycles. The immobilized cellulase was employed to decompose agro-waste and the maximum decomposition rate of 67.2 % was achieved. Conclusively, magnetic HNTs can serve as a potential support for enzyme immobilization with long term usage, good efficacy, reusability and easy recovery from solution.

Keywords: halloysite nanotubes, enzyme immobilization, cellulase, response surface methodology, magnetic recovery

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3992 Specific Language Impirment in Kannada: Evidence Form a Morphologically Complex Language

Authors: Shivani Tiwari, Prathibha Karanth, B. Rajashekhar

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Impairments of syntactic morphology are often considered central in children with Specific Language Impairment (SLI). In English and related languages, deficits of tense-related grammatical morphology could serve as a clinical marker of SLI. Yet, cross-linguistic studies on SLI in the recent past suggest that the nature and severity of morphosyntactic deficits in children with SLI varies with the language being investigated. Therefore, in the present study we investigated the morphosyntactic deficits in a group of children with SLI who speak Kannada, a morphologically complex Dravidian language spoken in Indian subcontinent. A group of 15 children with SLI participated in this study. Two more groups of typical developing children (15 each) matched for language and age to children with SLI, were included as control participants. All participants were assessed for morphosyntactic comprehension and expression using standardized language test and a spontaneous speech task. Results of the study showed that children with SLI differed significantly from age-matched but not language-matched control group, on tasks of both comprehension and expression of morphosyntax. This finding is, however, in contrast with the reports of English-speaking children with SLI who are reported to be poorer than younger MLU-matched children on tasks of morphosyntax. The observed difference in impairments of morphosyntax in Kannada-speaking children with SLI from English-speaking children with SLI is explained based on the morphological richness theory. The theory predicts that children with SLI perform relatively better in morphologically rich language due to occurrence of their frequent and consistent features that mark the morphological markers. The authors, therefore, conclude that language-specific features do influence manifestation of the disorder in children with SLI.

Keywords: specific language impairment, morphosyntax, Kannada, manifestation

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3991 Hypervirulent Klebsiella Pneumoniae in a South African Tertiary Hospital – Clinical Profile, Genetic Determinants and Virulence in Caenorhabditis Elegans

Authors: Dingiswayo Likhona, Arko-Cobbah Emmanuel, Carolina Pohl, Nthabiseng Z. Mokoena, Jolly Musoke

Abstract:

A distinct strain of Klebsiella pneumoniae (K. pneumoniae), referred to as hypervirulent (hvKp), is associated with invasive infections such as an invasive pyogenic liver abscess in young and healthy individuals. In South Africa, limited information is known about the prevalence and virulence of this hvKp strain. Thus, this study aimed to determine the prevalence of hvKp and virulence-associated factors in K. pneumoniae isolates from one of the largest Tertiary hospitals in a South African province. A total of 74 K. pneumoniae isolates were received from Pelonomi National Health Laboratory Services (NHLS), Bloemfontein. Virulence-associated genes (rmpA, capsule serotype K1/K2, iroB, and irp2) were screened, and the virulence of hvKp vs. classical Klebsiella pneumoniae (cKp) was investigated using Caenorhabditis elegans nematode model. The iutA (aerobactin transporter) gene was used as a primary biomarker of hvKp. An average of 12% (9/74) of cases were defined as hvKp. Moreover, hvKp was found to be significantly more virulent in vivo Caenorhabditis elegans relative to cKp. The virulence-associated genes (rmpA, iroB, hmv phenotype, and capsule K1/K2) were significantly (p< 0.05) associated with hvKp. Findings from this study confirm the presence of hvKp in one large Tertiary hospital in South Africa. However, the low prevalence and mild to moderate clinical presentation suggest a marginal threat to public health. Further studies in different settings are required to establish the true potential impact of hvKp in developing countries.

Keywords: hypervirulent klebsiella pneumoniae, virulence, caenorhabditis elegans, aerobactin (iutA)

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3990 The Role of Long-Chain Ionic Surfactants on Extending Drug Delivery from Contact Lenses

Authors: Cesar Torres, Robert Briber, Nam Sun Wang

Abstract:

Eye drops are the most commonly used treatment for short-term and long-term ophthalmic diseases. However, eye drops could deliver only about 5% of the functional ingredients contained in a burst dosage. To address the limitations of eye drops, the use of therapeutic contact lenses has been introduced. Drug-loaded contact lenses provide drugs a longer residence time in the tear film and hence, decrease the potential risk of side effects. Nevertheless, a major limitation of contact lenses as drug delivery devices is that most of the drug absorbed is released within the first few hours. This fact limits their use for extended release. The present study demonstrates the application of long-alkyl chain ionic surfactants on extending drug release kinetics from commercially available silicone hydrogel contact lenses. In vitro release experiments were carried by immersing drug-containing contact lenses in phosphate buffer saline at physiological pH. The drug concentration as a function of time was monitored using ultraviolet-visible spectroscopy. The results of the study demonstrate that release kinetics is dependent on the ionic surfactant weight percent in the contact lenses, and on the length of the hydrophobic alkyl chain of the ionic surfactants. The use of ionic surfactants in contact lenses can extend the delivery of drugs from a few hours to a few weeks, depending on the physicochemical properties of the drugs. Contact lenses embedded with ionic surfactants could be potential biomaterials to be used for extended drug delivery and in the treatment of ophthalmic diseases. However, ocular irritation and toxicity studies would be needed to evaluate the safety of the approach.

Keywords: contact lenses, drug delivery, controlled release, ionic surfactant

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3989 Perceptions of Cognitive Behavioural Therapy in Physiotherapy Management for Chronic Low Back Pain: A Qualitative Exploration of Stakeholder Views

Authors: Latifa Alenezi, Liz Croot, Janet Harris

Abstract:

Chronic Low Back Pain (CLBP) is one of the most common and recurrent musculoskeletal problems that causes patients to access health care services frequently. The Bio-psychosocial Model emphasises that psychological, behavioural and social factors contribute to the development and persistence of CLBP. Cognitive behavioural therapy (CBT) is a psychological pain management strategy that can be used by physiotherapists treating chronic low back pain. However, evidence of the effectiveness of CBT for CLBP varies between different studies. The proposed study was preceded by a mixed methods systematic review that found that CBT has a beneficial effect for CLBP patients when compared to waiting list or other treatments; however, there is variation in effectiveness across different settings. Little is known about how CBT is applied by physiotherapists in physiotherapy settings. The interest of this study is directed towards generating an explanation and understanding of why, when, and how some physiotherapists make decisions and choose to apply CBT for CLBP patients, whereas others do not. Also, how and for what type of CLBP patients does CBT work, and for whom might CBT not work? Therefore, the study will take a qualitative approach to explore CLBP patients’, physiotherapists’ and managers’ perceptions of CBT and how it is used in physiotherapy to enable a deeper understanding and richer explanation of CBT effectiveness and help to inform research and practice. The study will use grounded theory approach to generate an explanatory theory of the clinical application of CBT for CLBP in physiotherapy settings. Physiotherapists, patients and managers of physiotherapy services will be interviewed. Grounded theory techniques will be used to analyse the data. The presentation will describe findings from the interviews and the emerging theory. This research will help to further inform RCTs about the effectiveness of CBT for CLBP in physiotherapy.

Keywords: CBT, CLBP, perception, physiotherapy, theory

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3988 Anatomical Adaptations of Three Astragalus Species under Salt Stress

Authors: Faycal Boughalleb, Raoudha Abdellaoui

Abstract:

The effect of NaCl stress on root and leaf anatomy was investigated in three Astragalus species grown in 0-300 mM NaCl for 30 days under greenhouse conditions. Root cross section and cortex thickness was reduced under salt stress in both species while A. tenuifolius showed thinner cortex and the root cross section was unchanged. The epidermis stele thickness was unaffected by salinity in A. armatus and A. tenuifolius and was reduced in A. mareoticus with smaller xylem vessel size. In addition, vessel density and wall thickness of xylem was increased under salt conditions in the studies species. The entire lamina and mesophyll of the three species were thinner in salt-stressed plants. A. armatus and A. tenuifolius showed the higher thickness with increased size of the lower epidermis. NaCl (300 mM) reduced leaf water content by 41.5 % in A. mareoticus while it was unchanged in the other species. The size of the vascular bundle increased under salinity in A. tenuifolius leaves and it was unchanged in the other ones. A longer distance between leaf vascular bundle was occurred in A. mareoticus. The effects of NaCl on root and leaf ultrastructure are discussed in relation to the degree of salt resistance of these species. The unchanged biomass production under salt stress confirmed the higher tolerance oft A. tenuifolius to salinity. A. armatus was moderately salt tolerant with decrease of biomass production by 14.2 % while A. mareoticus was considered as salt sensitive plant when the decrease in biomass production reached 56.8%.

Keywords: Astragalus species, leaf ultrastructure, root anatomy, salt stress

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3987 Sustainable Urban Mobility: Rethinking the Bus Stop Infrastructures of Dhaka South

Authors: Hasnun Wara Khondker, M. Tarek Morad

Abstract:

Bangladesh is one of the most populous countries of the world in terms of density. Dhaka, the capital of Bangladesh currently has a population of approximately 15-16 million of which around 9 million people are accommodated in Dhaka South City Corporation (DSCC) within around 109 square kilometer area. Despite having various urban issues, country is at its pick of economic progress and Dhaka is the core of this economic growth. To ensure the proper economic development and citizens wellbeing, city needs an ingenious, congestion-free public transportation network. Bus stop/bus bay is an essential infrastructure for ensuring efficient public transportation flow within the city along with enhancing accessibility, user comfort, and safety through public amenities. At present, there is no established Mass Rapid Transit or Bus Rapid Transit network within the city and therefore these private owned buses are the only major mode of mass transportation of Dhaka city. DSCC has undertaken a project to re-design several bus stops and bus bays according to the universal standard for better urban mobility and user satisfaction. This paper will analyze the design approach of the bus stop/bay infrastructure within Dhaka South, putting the research lens on sustainable urban mobility with case studies of similar kind of urban context. The paper will also study the design process with setting several parameters, i.e., accessibility, passenger safety, comfort, sustainability, etc. Moreover, this research will recommend a guideline for designing a bus stop based on the analysis of the design methods.

Keywords: bus stop, Dhaka, public transportation, sustainable urban mobility, universal accessibility, user safety

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3986 A Comparative Study of the Effects of Vibratory Stress Relief and Thermal Aging on the Residual Stress of Explosives Materials

Authors: Xuemei Yang, Xin Sun, Cheng Fu, Qiong Lan, Chao Han

Abstract:

Residual stresses, which can be produced during the manufacturing process of plastic bonded explosive (PBX), play an important role in weapon system security and reliability. Residual stresses can and do change in service. This paper mainly studies the influence of vibratory stress relief (VSR) and thermal aging on residual stress of explosives. Firstly, the residual stress relaxation of PBX via different physical condition of VSR, such as vibration time, amplitude and dynamic strain, were studied by drill-hole technique. The result indicated that the vibratory amplitude, time and dynamic strain had a significant influence on the residual stress relief of PBX. The rate of residual stress relief of PBX increases first and then decreases with the increase of dynamic strain, amplitude and time, because the activation energy is too small to make the PBX yield plastic deformation at first. Then the dynamic strain, time and amplitude exceed a certain threshold, the residual stress changes show the same rule and decrease sharply, this sharply drop of residual stress relief rate may have been caused by over vibration. Meanwhile, the comparison between VSR and thermal aging was also studied. The conclusion is that the reduction ratio of residual stress after VSR process with applicable vibratory parameters could be equivalent to 73% of thermal aging with 7 days. In addition, the density attenuation rate, mechanical property, and dimensional stability with 3 months after VSR process was almost the same compared with thermal aging. However, compared with traditional thermal aging, VSR only takes a very short time, which greatly improves the efficiency of aging treatment for explosive materials. Therefore, the VSR could be a potential alternative technique in the industry of residual stress relaxation of PBX explosives.

Keywords: explosives, residual stresses, thermal aging, vibratory stress relief, VSR

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3985 Study of Demographic, Hematological Profile and Risk Stratification in Chronic Myeloid Leukemia Patients

Authors: Rajandeep Kaur, Rajeev Gupta

Abstract:

Background: Chronic myeloid leukemia (CML) is the most common leukaemia in India. The annual incidence of chronic myeloid leukemia in India was originally reported to be 0.8 to 2.2 per 1,00,000 population. CML is a clonal disorder that is usually easily diagnosed because the leukemic cells of more than 95% of patients have a distinctive cytogenetic abnormality, the Philadelphia chromosome (Ph1). The approval of tyrosine kinase inhibitors (TKIs), which target BCR-ABL1 kinase activity, has significantly reduced the mortality rate associated with chronic myeloid leukemia (CML) and revolutionized treatment. Material and Methods: 80 diagnosed cases of CML were taken. Investigations were done. Bone marrow and molecular studies were also done and with EUTOS, patients were stratified into low and high-risk groups and then treatment with Imatinib was given to all patients and the molecular response was evaluated at 6 months and 12 months follow up with BCR-ABL by RT-PCR quantitative assay. Results: In the study population, out of 80 patients in the study population, 40 were females and 40 were males, with M: F is 1:1. Out of total 80 patients’ maximum patients (54) were in 31-60 years age group. Our study showed a most common symptom of presentation is abdominal discomfort followed by fever. Out of the total 80 patients, 25 (31.3%) patients had high EUTOS scores and 55 (68.8%) patients had low EUTOS scores. On 6 months follow up 36.3% of patients had Complete Molecular Response, 16.3% of patients had Major Molecular Response and 47.5% of patients had No Molecular Response but on 12 months follow up 71.3% of patients had Complete Molecular Response, 16.25% of patients had Major Molecular Response and 12.5% patients had No Molecular Response. Conclusion: In this study, we found a significant correlation between EUTOS score and Molecular response at 6 months and 12 months follow up after Imatinib therapy.

Keywords: chronic myeloid leukemia, European treatment and outcome study score, hematological response, molecular response, tyrosine kinase inhibitor

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3984 Patterns of Change in Perception of Imagined and Physically Induced Pain over the Course of Repeated Thermal Stimulations

Authors: Boroka Gács, Tibor Szolcsányi, Árpad Csathó

Abstract:

Background: Individuals frequently show habituation to repeated noxious heat. However, given the defensive function of human pain processing, it is reasonable to assume that individuals imagine that they would become increasingly sensitive to repeated thermal pain stimuli. To the best of the authors' knowledge, no previous studies have, however, been addressed to this assumption. Therefore, in the current study, we investigated how healthy human individuals imagine the intensity of repeated thermal pain stimulations, and compared this with the intensity ratings given after physically induced thermal pain trials. Methods: Healthy participants (N = 20) gave pain intensity ratings in two conditions: imagined and real thermal pain. In the real pain condition thermal pain stimuli of two intensities (minimal and moderate pain) were delivered in four consecutive trials. The duration of the peak temperature was 20s, and stimulation was always delivered to the same location. In each trial, participants rated the pain intensity twice, 5s and 15s after the onset of the peak temperature. In the imagined pain condition, participants were subjected to a reference pain stimulus and then asked to imagine and rate the same sequence of stimulations as in the induced pain condition. Results: Ratings of imagined pain and physically induced pain followed opposite courses over repeated stimulation: Ratings of imagined pain indicated sensitization whereas ratings for physically induced pain indicated habituation. The findings were similar for minimal and moderate pain intensities. Conclusions: The findings suggest that, rather than habituating to pain, healthy individuals imagine that they would become increasingly sensitive to repeated thermal pain stimuli.

Keywords: habituation, imagined pain, pain perception, thermal stimulation

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3983 Revisiting the Link between Corporate Social Performance and Corporate Financial Performance Post 2008 Global Economic Crisis

Authors: Anand Choudhary

Abstract:

Following the global economic crisis in 2008, businesses and more especially the big multinational conglomerates were increasingly viewed by the people world over as one of the major causes of the economic problems faced by millions globally, in terms of job loss and lifetime savings being wiped out as banks and pension funds went bankrupt and people stared at an insecure financial future. This caused a lot of resentment in the public against big businesses and fueled several protest movements by the people such as “Occupy Wall Street” in different parts of the world. This forced the big businesses to respond to the challenge by adopting more people-centric policies and initiatives for local communities in societies where they operate as part of their corporate social responsibility (CSR), in order to regain their social acceptance among the people whilst earning their ‘social license to operate’. The current paper studies many of such large MNCs across the United States of America, India and South Africa, which changed the way they did business earlier, following the global economic crisis in 2008, by incorporating capacity building initiatives for local communities as part of their CSR strategy and explores whether it has contributed to improving their financial performance. It is a conceptual research paper using secondary source data. The findings reveal that there is a positive correlation between the companies’ corporate social performance and corporate financial performance. In addition, the findings also bring to light that the MNCs examined as part of the current paper have improved their image in the eyes of their stakeholders following the change in their CSR strategy and initiatives.

Keywords: corporate social responsibility (CSR), Corporate Social Performance (CSP), Corporate Financial Performance (CFP), local communities

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3982 Utilization of “Adlai” (Coix lacryma-jobi L) Flour as Wheat Flour Extender in Selected Baked Products in the Philippines

Authors: Rolando B. Llave Jr.

Abstract:

In many countries, wheat flour is used an essential component in production/preparation of bread and other baked products considered to have a significant role in man’s diet. Partial replacement of wheat flour with other flours (composite flour) in preparation of the said products is seen as a solution to the scarcity of wheat flour (in non-wheat producing countries), and improved nourishment. In composite flour, other flours may come from cereals, legumes, root crops, and those that are rich in starch. Many countries utilize whatever is locally available. “Adlai” or Job’s tears is a tall cereal plant that belongs to the same family of grass as wheat, rice, and corn. In some countries, it is used as an ingredient in producing many dishes and alcoholic and non-alcoholic beverages. As part of the Food Staple Self-Sufficiency Program (FSSP) of the Department of Agriculture (DA) in the Philippines, “adlai” is being promoted as alternative food source for the Filipinos. In this study, the grits coming from the seeds of “adlai” were turned into flour. The resulting flour was then used as partial replacement for wheat flour in selected baked products namely “pan de sal” (salt bread), cupcakes and cookies. The supplementation of “adlai” flour ranged 20%-45% with 20%-35% for “pan de sal”; 30%-45% for cupcakes; and 25% - 40% for cookies. The study was composed of four (4) phases. Phase I was product formulation studies. Phase II included the acceptability test/sensory evaluation of the baked products where the statistical analysis of the data gathered followed. Phase III was the computation of the theoretical protein content of the most acceptable “pan de sal”, cupcake and cookie, and lastly, in Phase IV, cost benefit was analyzed, specifically in terms of the direct material cost.

Keywords: “adlai”, composite flour, supplementation, sensory evaluation

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3981 The Role of Urban Development Patterns for Mitigating Extreme Urban Heat: The Case Study of Doha, Qatar

Authors: Yasuyo Makido, Vivek Shandas, David J. Sailor, M. Salim Ferwati

Abstract:

Mitigating extreme urban heat is challenging in a desert climate such as Doha, Qatar, since outdoor daytime temperature area often too high for the human body to tolerate. Recent studies demonstrate that cities in arid and semiarid areas can exhibit ‘urban cool islands’ - urban areas that are cooler than the surrounding desert. However, the variation of temperatures as a result of the time of day and factors leading to temperature change remain at the question. To address these questions, we examined the spatial and temporal variation of air temperature in Doha, Qatar by conducting multiple vehicle-base local temperature observations. We also employed three statistical approaches to model surface temperatures using relevant predictors: (1) Ordinary Least Squares, (2) Regression Tree Analysis and (3) Random Forest for three time periods. Although the most important determinant factors varied by day and time, distance to the coast was the significant determinant at midday. A 70%/30% holdout method was used to create a testing dataset to validate the results through Pearson’s correlation coefficient. The Pearson’s analysis suggests that the Random Forest model more accurately predicts the surface temperatures than the other methods. We conclude with recommendations about the types of development patterns that show the greatest potential for reducing extreme heat in air climates.

Keywords: desert cities, tree-structure regression model, urban cool Island, vehicle temperature traverse

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3980 Nutritional Importance and Functional Properties of Baobab Leaves

Authors: Khadijat Ayanpeju Abdulsalam, Bolanle Mary Olawoye, Paul Babatunde Ayoola

Abstract:

The potential of Baobab leaves is understudied and not yet fully documented. The purpose of this work is to highlight the important nutritional value and practical qualities of baobab leaves. In this research, proximate analysis was studied to determine the macronutrient quantitative analysis in baobab leaves. Studies were also conducted on other characteristics, such as moisture content, which is significant to the food business since it affects food quality, preservation, and resistance to deterioration. Dietary fiber, which was also studied, has important health benefits, such as lowering blood cholesterol levels by lowering low-density lipoprotein or "bad" cholesterol. It functions as an anti-obesity and anti-diabetic agent, lowering the likelihood of haemorrhoids developing. Additionally, increasing face bulk and short-chain fatty acid synthesis improves gastrointestinal health and overall wellness. Baobab leaves had a moisture content of 6.4%, fat of 16.1%, ash of 3.2%, protein of 18.7%, carbohydrate 57.2% and crude fiber of 4.1%. The minerals determined in the sample of baobab leaves are Ca, Fe, Mg, K, Na, P, and Zn with Potassium (347.6±0.70) as the most abundant mineral while Zn (9.31±0.60) is the least abundant. The functional properties studied include pH, gelation temperature, bulk density, water absorption capacity, oil absorption capacity, foaming property, emulsifying property, and stability and swelling capacity, which are 8.72, 29, 0.39, 138, 98.20, 0.80, 72.80, and 73.50 respectively. The Fourier Transform InfraRed absorption spectra show bands like C=O, C-Cl and N-H. Baobab leaves are edible, nutritious, and non-toxic, as the mineral contents are within the required range.

Keywords: dietary fibre, proximate analysis, macronutrients, minerals, baobab leaves, frequency range

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3979 Genetic Polymorphism in the Vitamin D Receptor Gene and 25-Hydroxyvitamin D Serum Levels in East Indian Women with Polycystic Ovary Syndrome

Authors: Dipanshu Sur, Ratnabali Chakravorty

Abstract:

Background: Polycystic ovary syndrome (PCOS) is the most common metabolic abnormality such as changes in lipid profile, diabetes, hypertension and metabolic syndrome occurring in young women of reproductive age. Low vitamin D levels were found to be associated with the development of obesity and insulin resistance in women with PCOS. Variants on vitamin D receptor (VDR) gene have also been related to metabolic comorbidities in general population. Aim: The aim of this case-control study was to investigate whether the VDR gene polymorphisms are associated with susceptibility to PCOS. Methods: Women with PCOS and a control group, all aged 16-40 years, were enrolled. Genotyping of VDR Fok-I (rs2228570), VDR Apa-I (rs7975232) as well as GC (rs2282679), DHCR7 (rs12785878) SNPs between groups were determined by using direct sequencing. Serum 25-hydroxyvitamin D [25(OH)] levels were measured by ELISA. Results: Mean serum 25(OH)D in the PCOS and control samples were 19.08±7 and 23.27±6.03 (p=0.048) which were significantly lower in PCOS patients compared with controls. CC genotype of the VDR Apa-I SNP was same frequent in PCOS (25.6%) and controls (25.6%) (OR: 0.9995; 95%CI: 0.528 to 1.8921; p= 0.9987). The CC genotype was also significantly associated with both lower E2 (p=0.031) and Androstenedione levels (p=0.062). We observed a significant association of GC polymorphism with 25(OH)D levels. PCOS women carrying the GG genotype (in GC genes) had significantly higher risk for vitamin D deficiency than women carrying the TT genotype. Conclusions: In conclusion, data from this study indicate that vitamin D levels are lower, and vitamin D deficiency more frequent, in PCOS than in controls. The present findings suggest that the Apa-I, Fok-I polymorphism of the VDR gene is associated with PCOS and seems to modulate ovarian steroid secretion. Further studies are needed to better clarify the biological mechanisms by which the polymorphism influences PCOS risk.

Keywords: vitamin D receptor, polymorphism, vitamin D, polycystic ovary syndrome

Procedia PDF Downloads 290