Search results for: higher education studies

Authors: Atefeh Abedini, Fatemeh Razavi, Mihan Pourabdollah Toutkaboni, Hossein Mehravaran, Arda Kiani

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In countries with the highest prevalence of tuberculosis, such as Iran, the differentiation of malignant tumors from non-malignant is very important. In this study, which was conducted for the first time among the Iranian population, the utility of the ultrasonographic morphological characteristics in patients undergoing EBUS was used to distinguish the non-malignant versus malignant lymph nodes. The morphological characteristics of lymph nodes, which consist of size, shape, vascular pattern, echogenicity, margin, coagulation necrosis sign, calcification, and central hilar structure, were obtained during Endobronchial Ultrasound-Guided Trans-Bronchial Needle Aspiration and were compared with the final pathology results. During this study period, a total of 253 lymph nodes were evaluated in 93 cases. Round shape, non-hilar vascular pattern, heterogeneous echogenicity, hyperechogenicity, distinct margin, and the presence of necrosis sign were significantly higher in malignant nodes. On the other hand, the presence of calcification and also central hilar structure were significantly higher in the benign nodes (p-value ˂ 0.05). Multivariate logistic regression showed that size>1 cm, heterogeneous echogenicity, hyperechogenicity, the presence of necrosis signs and, the absence of central hilar structure are independent predictive factors for malignancy. The accuracy of each of the aforementioned factors is 42.29 %, 71.54 %, 71.90 %, 73.51 %, and 65.61 %, respectively. Of 74 malignant lymph nodes, 100% had at least one of these independent factors. According to our results, the morphological characteristics of lymph nodes based on Endobronchial Ultrasound-Guided Trans-Bronchial Needle Aspiration can play a role in the prediction of malignancy.

Keywords: EBUS-TBNA, malignancy, nodal characteristics, pathology

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Authors: Dumont Maxime, Correia Carlos, Sauvage Jean-François, Schwartz Noah, Gray Morgan

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Context: The concept of the segmented telescope is unavoidable to build extremely large telescopes (ELT) in the quest for spatial resolution, but it also allows one to fit a large telescope within a reduced volume of space (JWST) or into an even smaller volume (Standard Cubesat). Cubesats have tight constraints on the computational burden available and the small payload volume allowed. At the same time, they undergo thermal gradients leading to large and evolving optical aberrations. The pupil segmentation comes nevertheless with an obvious difficulty: to co-phase the different segments. The CubeSat constraints prevent the use of a dedicated wavefront sensor (WFS), making the focal-plane images acquired by the science detector the most practical alternative. Yet, one of the challenges for the wavefront sensing is the non-linearity between the image intensity and the phase aberrations. Plus, for Earth observation, the object is unknown and unrepeatable. Recently, several studies have suggested Neural Networks (NN) for wavefront sensing; especially convolutional NN, which are well known for being non-linear and image-friendly problem solvers. Aims: We study in this paper the prospect of using NN to measure the phasing aberrations of a segmented pupil from the focal-plane image directly without a dedicated wavefront sensing. Methods: In our application, we take the case of a deployable telescope fitting in a CubeSat for Earth observations which triples the aperture size (compared to the 10cm CubeSat standard) and therefore triples the angular resolution capacity. In order to reach the diffraction-limited regime in the visible wavelength, typically, a wavefront error below lambda/50 is required. The telescope focal-plane detector, used for imaging, will be used as a wavefront-sensor. In this work, we study a point source, i.e. the Point Spread Function [PSF] of the optical system as an input of a VGG-net neural network, an architecture designed for image regression/classification. Results: This approach shows some promising results (about 2nm RMS, which is sub lambda/50 of residual WFE with 40-100nm RMS of input WFE) using a relatively fast computational time less than 30 ms which translates a small computation burder. These results allow one further study for higher aberrations and noise.

Keywords: wavefront sensing, deep learning, deployable telescope, space telescope

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Authors: Uraib Sharaha, Ahmad Salman, Eladio Rodriguez-Diaz, Elad Shufan, Klaris Riesenberg, Irving J. Bigio, Mahmoud Huleihel

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Antimicrobial drugs have an important role in controlling illness associated with infectious diseases in animals and humans. However, the increasing resistance of bacteria to a broad spectrum of commonly used antibiotics has become a global health-care problem. Rapid determination of antimicrobial susceptibility of a clinical isolate is often crucial for the optimal antimicrobial therapy of infected patients and in many cases can save lives. The conventional methods for susceptibility testing like disk diffusion are time-consuming and other method including E-test, genotyping are relatively expensive. Fourier transform infrared (FTIR) microscopy is rapid, safe, and low cost method that was widely and successfully used in different studies for the identification of various biological samples including bacteria. The new modern infrared (IR) spectrometers with high spectral resolution enable measuring unprecedented biochemical information from cells at the molecular level. Moreover, the development of new bioinformatics analyses combined with IR spectroscopy becomes a powerful technique, which enables the detection of structural changes associated with resistivity. The main goal of this study is to evaluate the potential of the FTIR microscopy in tandem with machine learning algorithms for rapid and reliable identification of bacterial susceptibility to antibiotics in time span of few minutes. The bacterial samples, which were identified at the species level by MALDI-TOF and examined for their susceptibility by the routine assay (micro-diffusion discs), are obtained from the bacteriology laboratories in Soroka University Medical Center (SUMC). These samples were examined by FTIR microscopy and analyzed by advanced statistical methods. Our results, based on 550 E.coli samples, were promising and showed that by using infrared spectroscopic technique together with multivariate analysis, it is possible to classify the tested bacteria into sensitive and resistant with success rate higher than 85% for eight different antibiotics. Based on these preliminary results, it is worthwhile to continue developing the FTIR microscopy technique as a rapid and reliable method for identification antibiotic susceptibility.

Keywords: antibiotics, E. coli, FTIR, multivariate analysis, susceptibility

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Authors: Fangyuan Shao, Wei Liu, Deli Gao

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Polycrystalline diamond compact (PDC) bits have occupied a large market of unconventional oil and gas drilling. The application of PDC bits benefits from the efficient rock breaking of PDC cutters. In response to increasingly complex formations, many shaped cutters have been invited, but many of them have not been solved by the mechanism of rock breaking. In this paper, two kinds of PDC cutters: a new axe-shaped (NAS) cutter and cylindrical cutter (benchmark) were studied by laboratory experiments. NAS cutter is obtained by optimizing two sides of axe-shaped cutter with curved surfaces. All the cutters were put on a vertical turret lathe (VTL) in the laboratory for cutting tests. According to the cutting distance, the VTL tests can be divided into two modes: single-turn rotary cutting and continuous cutting. The cutting depth of cutting (DOC) was set at 1.0 mm and 2.0 mm in the former mode. The later mode includes a dry VTL test for thermal stability and a wet VTL test for wear resistance. Load cell and 3D optical profiler were used to obtain the value of cutting forces and wear area, respectively. Based on the findings of the single-turn rotary cutting VTL tests, the performance of A NAS cutter was better than the benchmark cutter on elastoplastic material cutting. The cutting forces (normal forces, tangential force, and radial force) and special mechanical energy (MSE) of a NAS cutter were lower than that of the benchmark cutter under the same condition. It meant that a NAS cutter was more efficient on elastoplastic material breaking. However, the wear resistance of a new axe-shaped cutter was higher than that of a benchmark cutter. The results of the dry VTL test showed that the thermal stability of a NAS cutter was higher than that of a benchmark cutter. The cutting efficiency can be improved by optimizing the geometric structure of the PDC cutter. The change of thermal stability may be caused by the decrease of the contact area between cutter and rock at given DOC. The conclusions of this paper can be used as an important reference for PDC cutters designers.

Keywords: axe-shaped cutter, PDC cutter, rotary cutting test, vertical turret lathe

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Authors: A. H. Nanher, N. P. Singh

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In India, Agriculture is largely in rice- based cropping system. It has indicated decline in factor productivity along with emergence of multi - nutrient deficiency, buildup of soil pathogen and weed flora because it operates and removes nutrients from the same rooting depth. In designing alternative cropping systems, the common approaches are crop intensification, crop diversification and cultivar options. The intensification leads to the diversification of the cropping system. Intensification is achieved by introducing an additional component crop in a pre-dominant sequential system by desirable adjustments in cultivars of one or all the component crops. Invariably, this results in higher land use efficiency and productivity per unit time Crop Diversification through such crop and inclusion of fodder crops help to improve the economic situation of small and marginal farmers because of higher income. Inclusion of crops in sequential and intercropping systems reduces some obnoxious weeds through formation of canopies due to competitive planting pattern and thus provides an opportunity to utilize cropping systems as a tool of weed management with non-chemical means. Use of organic source not only acts as supplement for fertilizer (nitrogen) but also improve the physico-chemical properties of soils. Production and use of nitrogen rich biomass offer better prospect for supplementing chemical fertilizers on regular basis. Such biological diversity brings yield and economic stability because of its potential for compensation among components of the system. In a particular agro-climatic and resource condition, the identification of most suitable crop sequence is based on its productivity, stability, land use efficiency as well as production efficiency and its performance is chiefly judged in terms of productivity and net return.

Keywords: integrated farming systems, sustainable intensification, system of crop intensification, wheat

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Authors: B. I. Waziri, M. A. Yahaya

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Background: Practice of shisha smoking involves the use of a multi-stemmed instrument to smoke tobacco or non-tobacco herbal mixture where the smoke is designed to pass through water or other liquid before reaching the smoker. The presence of tobacco content and the use of charcoal when burning the ingredients in this popular practice necessitate for investigation of many physiological parameters of habitual shisha smokers in our environment. Methods: 103 young shisha smokers, regular in the practice for more than three years living in Nasarawa, Kano state, Nigeria, were recruited for the study. The controls were 100 university students (nonsmokers) match for age (18 - 30 years), sex and BMI (20 - 24) with the smokers. Participants with known history of cigarette smoking, cardiovascular or respiratory diseases were excluded. Ethical approval was obtained from the Ministry of Health, Kano Nigeria. Hear rate, blood pressure and percentage oxygen saturation (SPO₂) were measured using stethoscope, sphygmomanometer and pulse oximeter respectively. Data were analyzed using IBM SPSS version 20 and mean values of the measured parameters were compared between the smokers and controls using independent sample t-test. P-values < 0.05 were considered significant. Results: The mean Heart rate was found to be significantly higher (p = 0.01) in the shisha smokers (91.32 ± 0.84) compared to controls (79.19 ± 1.18). Systolic and diastolic blood pressure was also higher (p = 0.00) in the shisha smokers (128.75 ± 1.11 and 85.85 ± 0.78 respectively) compared to controls with the systolic and diastolic pressure of 116.64 ± 0.82 and 80.39 ± 0.83 respectively. SPO₂ was significantly lower (p = 0.00) in the shisha smokers (91.98% ± 0.42%) compared to the controls (97.98 ± 0.18). Conclusion: Habitual Shisha Smoking caused a significant increase in Heart rate, both systolic and diastolic blood pressure and a significant decrease in SPO2 among youth in Kano State, Nigeria.

Keywords: blood pressure, heart rate, shisha, youth

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Authors: Randall E. Osborne, Seth A. Doty

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As participation in organized sports increases, so does the risk of sustaining an athletic injury. These unfortunate injuries result in missed time from practice and, inevitably, the field of competition. Recovery time plays a pivotal role in the overall rehabilitation of the athlete. With time and rehabilitation, an athlete’s physical injury can be properly treated. However, there seem to be few measures assessing psychological recovery from injury. Although an athlete has been cleared to return to play, there may still be lingering doubt about their injury. Overall, there is a vast difference between being physically cleared to play and being psychologically ready to return to play. Certain personality traits might serve as predictors of an individual’s rate of psychological recovery from an injury. The purpose of this research study is to explore the correlations between athletes’ personality and their recovery from an athletic injury, specifically, examining how locus of control has been utilized through other studies and can be beneficial to the current study. Additionally, this section will examine the link between hardiness and coping strategies. In the current study, mental toughness is being tested, but it is important to determine the link between these two concepts. Hardiness and coping strategies are closely related and can play a major role in an athlete’s mental toughness. It is important to examine competitive trait anxiety to illustrate perceived anxiety during athletic competition. The Big 5 and Social Support will also be examined in conjunction with recovery from athletic injury. Athletic injury is a devastating and common occurrence that can happen in any sport. Injured athletes often require resources and treatment to be able to return to the field of play. Athletes become more involved with physical and mental treatment as the length of recovery time increases. It is very reasonable to assume that personality traits would be predictive of athlete recovery from injury. The current study investigated the potential relationship between personality traits and recovery time; more specifically, the personality traits of locus of control, hardiness, social support, competitive trait anxiety, and the “Big 5” personality traits. Results indicated that athletes with a higher internal locus of control tend to report being physically ready to return to play and “ready” to return to play faster than those with an external locus of control. Additionally, Openness to Experience (among the Big 5 personality dimensions) was also related to the speed of return to play.

Keywords: athlete, injury, personality, readiness to play, recovery

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Authors: Amani Jaber-Awida

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This study examines two bilingual phenomena in the narratives of Arabic Hebrew and Hebrew-English bilingual adults in Israel: CO memories and code-switching (CS). The study examined these phenomena in the context of autobiographical memory, using a cue word technique. Student experimenters held two sessions in the homes of the participants. In separate language sessions, the participant was asked to look first at each of 16 cue words and then to state a concrete memory. After stating the memory, participants reported whether their memories were in the same language of the experiment session or different. Memories were classified as ‘Crossovers’ (CO) or ‘Same Language’ (SL) according to participants' self-reports. Participants were also required to elaborate about the setting, interlocutors and other languages involved in the specific memory. Beyond replicating the procedure of cuing technique, one memory from a specific lifespan period was chosen per participant, and the participant was required to provide further details about it. For the more detailed memories, CS count was conducted. Both bilingual groups confirmed the Reminiscence Bump phenomenon, retrieving more memories in the 10-30 age period. CO memories prevailed in second language sessions (L2). Same language memories were more abundant in first language sessions (L1). Higher CS frequency was found in L2 sessions. Finally, as predicted, 'individual' CS was prevalent in L2 sessions, but 'community-based' CS was not higher in L1 sessions. The two bilingual measures in this study, crossovers, and CS came from different research traditions, the former from an experimental paradigm in the psychology of autobiographical memory based on self-reported judgments, the latter a behavioral measure from linguistics. This merger of approaches offers new insight into the field of bilingual autobiographical memory. In addition, the study attempted to shed light on the investigation of motivations for CS, beginning with Walters’ SPPL Model and concluding with a distinction between ‘community-based’ and individual motivations.

Keywords: bilinguals, code-switching, crossover memories, narratives

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Authors: Malik Shoeb Ahmad

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The aim of the present study is to carry out investigations on Class F fly ash obtained from NTPC thermal power plant, Dadri, U.P. (India) and electroplating waste sludge from Aligarh, U.P. (India) along with geofibre for its subsequent utilization in various geotechnical and highway engineering applications. The experimental studies such as California bearing ratio (CBR) tests were carried out to evaluate the strength of plain fly ash as well as fly ash-waste sludge mix reinforced with geofibre, as the CBR value is the vital parameters used in the design of flexible and rigid pavements. Results of the study show that the strength of the mix is highly dependent on the curing period and the sludge and geofibre content. The CBR values were determined for mix containing fly ash (83.5-93.5%), waste sludge (5-15%) and 1-2% geofibre. However, out of the various combinations of mixes the CBR value of the mix 88.5%FA+10%S+1.5%GF at 28 days of curing was found to be 53.52% when compared with the strength of plain fly ash. It has been observed that the fibre inclusion increases the strength of the plain fly ash and fly ash-waste sludge specimens by changing their brittle to ductile behavior. The TCLP leaching test was also conducted to determine the heavy metal concentration in the optimized mix. The results of TCLP test show that the heavy metal concentration in the mix 88.5%FA+10%S+1.5%G at 28 days of curing reduced substantially from 24 to 98% when compared with the concentration of heavy metals in the waste sludge collected from source. It has also been observed that the pH of the leachate of this mix is between 9-11, which ensures the proper stabilization of the heavy metals present in the mix. Hence, this study will certainly help in mass scale utilization of two industrial wastes viz., electroplating waste and fly ash, which are causing pollution to the environment to a great extent.

Keywords: Dadri fly ash, geofibre, electroplating waste sludge, CBR, TCLP

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Authors: Daniela Lamaison Sepulveda

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Critical media literacy teaches people to think analytically about the information they receive through the media. It is heavily influenced by Paulo Freire’s critical pedagogy and the necessity of becoming conscious of one’s reality in order to transform it. This qualitative research examines the case of Bolivia, which experienced dramatic political change after the first indigenous president, Evo Morales, was elected in 2006. In 2010, the government passed an education reform — the Avelino Siñani Elizardo Pérez (ASEP) —that draws heavily on decolonial thought and the Freirean notion of critical consciousness. The extent to which these theories were implemented in practice is evaluated in context of a media literacy project, run by an NGO, that trains secondary school teachers from public schools across Bolivia through yearly workshops ranging from producing media to identifying fake news. This context is examined against the backdrop of the highly contested general elections in October 2019. While there is plenty of literature that outlines the benefits of teaching media literacy in the classroom and different ways to apply it, little research has been done analysing implementation at an institutional level and how to best enable teachers who are motivated to teach the subject. Through semi-structured interviews, document analysis and naturalistic observations, this study aims to identify the struggles faced by teachers who are dedicated to teaching critical media literacy in their classrooms and how they navigate educational spaces while being subject to a demanding national curriculum that supposedly also seeks to promote critical thinking. The interplay between the aspirations of teachers and NGOs in contrast to the top-down discourse and policy of governmental institutions provides for a very enlightening case. By exploring these institutional, cultural, sociopolitical and economic barriers the teachers face, this research attempts to contribute to the debate in media literacy theories concerned with implementing the practice in schools.

Keywords: media literacy, critical pedagogy, teacher agency, misinformation, education reform, Bolivia

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Authors: Ivan Zupan, Tomislav Saric, Suzana Tkalcic

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IMUNO-2865® is a commercially available, β–glucan based, natural hemicellulose compound with proven immunostimulative properties in people, domestic and some aquatic animals. During the experimental feeding trial with IMUNO-2865® in juvenile wild-caught chub under laboratory conditions, supplementation resulted in overall higher growth performance for all experimental groups regardless of the concentration of the added compound. The maximum, 5% concentration of the supplement, resulted in highest weight gain and calculated specific growth rate. In sea bream, as economically most important species in the Mediterranean aquaculture, significant increases in numbers of monocytes and heterophils were observed in the group supplemented with 2.5 % of IMUNO-2865® in the feed. An overall increase of erythrocytes was noted by the end of the experiment, although with variable distribution among groups. Blood Ca++ levels, total proteins, and total NH₃ were significantly higher after 60 days of feeding in all treatment groups compared to the control and remained elevated in the treated group following the secession of supplementation. Superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and serum paraoxonase PON1 (U/L) showed similar trends. All these parameters are playing a significant role in either oxygen supplementation of tissues, or anabolic and catabolic processes that on molecular levels contribute to the overall health and immune-building capacity of cells and tissues. The complete lack of mortality in sea bream and presented increases in cellular, biochemical and oxidative stress parameters in the blood suggest that the IMUNO-2865® represents a safe dietary supplement for in aquaculture, with an overall positive and potentially immunostimulative effect on farmed fish.

Keywords: IMUNO-2865®, β–glucans, Mediterranean aquaculture, fish imunnostimulans

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Authors: Anne Hovgaard Jorgensen

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This study investigates how Muslim fathers in Denmark are struggling to overcome notions of mistrust from teachers and educators. Starting from school-home-cooperation (parent conferences, school-home communication, etc.), the study finds that many Muslim fathers do not feel acknowledged as a resource in the upbringing of their children. To explain these experiences further, the study suggest the notion of ‘mistrusted masculinity’ to grasp the controlling image these fathers meet in various schools and child-care-institutions in the Danish Welfare state. The paper is based on 9 months of fieldwork in a Danish school, a social housing area and in various ‘father groups’ in Denmark. Additional, 50 interviews were conducted with fathers, children, mothers, schoolteachers, and educators. By using Connell's concepts 'hegemonic' and 'marginalized' masculinity as steppingstones, the paper argues that these concepts might entail a too static and dualistic picture of gender. By applying the concepts of 'emergent masculinity' and 'emergent fatherhood' the paper brings along a long needed discussion of how Muslim men in Denmark are struggling to overcome and change the controlling images of them as patriarchal and/or ignorant fathers regarding the upbringing of their children. As such, the paper shows how Muslim fathers are taking action to change this controlling image, e.g. through various ‘father groups’. The paper is inspired by the phenomenological notions of ‘experience´ and in the light of this notion, the paper tells the fathers’ stories about their upbringing of their children and aspirations for fatherhood. These stories share light on how these fathers take care of their children in everyday life. The study also shows that the controlling image of these fathers have affected how some Muslim fathers are actually being fathers. The study shows that fear of family-interventions from teachers or social workers e.g. have left some Muslim fathers in a limbo, being afraid of scolding their children, and being confused of ‘what good parenting in Denmark is’. This seems to have led to a more lassie fair upbringing than these fathers actually wanted. This study is important since anthropologists generally have underexposed the notion of fatherhood, and how fathers engage in the upbringing of their children. Over more, the vast majority of qualitative studies of fatherhood have been on white middleclass fathers, living in nuclear families. In addition, this study is crucial at this very moment due to the major refugee crisis in Denmark and in the Western world in general. A crisis, which has resulted in a vast number of scare campaigns against Islam from different nationalistic political parties, which enforces the negative controlling image of Muslim fathers.

Keywords: fatherhood, Muslim fathers, mistrust, education

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Authors: Sekena H. Abd El-Aziem, Heba A. M. Abd El-Kader, Sally S. Alam, Othman E. Othman

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Growth hormone (GH) is an anabolic hormone synthesized and secreted by the somatotroph cells of the anterior lobe of the pituitary gland in a circadian and pulsatile manner, the pattern of which plays an important role in postnatal longitudinal growth and development, tissue growth, lactation, reproduction as well as protein, lipid and carbohydrate metabolism. The aim of this study was to detect the genetic polymorphism of GH gene in five camel breeds reared in Egypt; Sudany, Somali, Mowaled, Maghrabi and Falahy, using PCR-RFLP technique. Also this work aimed to identify the single nucleotide polymorphism between different genotypes detected in these camel breeds. The amplified fragment of camel GH at 613-bp was digested with the restriction enzyme MspI and the result revealed the presence of three different genotypes; CC, CT and TT in tested breeds and significant differences were recorded in the genotype frequencies between these camel breeds. The result showed that the Maghrabi breed that is classified as a dual purpose camels had higher frequency for allele C (0.75) than those in the other tested four breeds. The sequence analysis declared the presence of a SNP (C→T) at position 264 in the amplified fragment which is responsible for the destruction of the restriction site C^CGG and consequently the appearance of two different alleles C and T. The nucleotide sequences of camel GH alleles T and C were submitted to nucleotide sequences database NCBI/Bankit/GenBank and have accession numbers: KP143517 and KP143518, respectively. It is concluded that only one SNP C→T was detected in GH gene among the five tested camel breeds reared in Egypt and this nucleotide substitution can be used as a marker for the genetic biodiversity between camel breeds reared in Egypt. Also, due to the possible association between allele C and higher growth rate, we can used it in MAS for camels and enter the camels possess this allele in breeding program as a way for enhancement of growth trait in camel breeds reared in Egypt.

Keywords: camel breeds in Egypt, GH, PCR-RFLP, SNPs

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Authors: Priscilla Echeverria

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For us grown up in neoliberal societies, it is not always clear that we have not only incorporated an economic logic into our subjectivities, but a technical reason, an instrumental way of relationship with the environment inspired in a control interest that constantly dehumanizes us as takes away our capacity of action, becoming mere objects or bureaucrats, stripped of our citizen dimension to participate in social and political issues responsibly and creatively. To restore the capacity of action -agency- is urgent in our societies to strengthen better democracies. On this, the formal educational system plays a crucial role, which in turn needs teachers prepared to understand their role as integral educators instead of mere curriculum managers. For this reason, initial teacher formation (ITF) programs must assume the responsibility of helping them to develop an ethical/political/epistemic pedagogical agency to deal with a technical school culture and, in turn, able to relate to their students in democratic ways to help them to develop their agency capacities. By highlighting a perspective of education as the opposite of technocracy and bureaucracy, this talk precisely addresses ITF as a crucial and formative space to restore a perspective of what a critical education can look like, enabling pedagogy students with pedagogical agency capacities to, in turn, allow their future students to develop it. This discussion is part of my doctoral research, "The importance of developing the capacity for ethical-political-epistemic agency in novice teachers during initial teacher formation to contribute to social justice", which I currently develop in the Educational Research program of the University of Lancaster, United Kingdom, as a Conicyt fellow for the 2019 cohort. This presentation specifically offers preliminary results of the analysis of critical incidents as a research methodological tool to analyse the capacity of pedagogical agency deployed by novice teachers in their first pedagogical experiences in the Chilean context.

Keywords: initial teacher formation, pedagogical agency, pedagogical interaction, hidden curriculum, critical pedagogy, social justice

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Authors: Ghazal Mortazavi, S. M. J. Mortazavi

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Although seems to be ultra-conservative, it has recently been suggested that whenever it is possible, pregnant women should postpone dental amalgam restorations to avoid the toxic effect of mercury on the foetus. Dental amalgam fillings cause significant exposure to elemental mercury vapour in the general population. Over the past several years, our lab has focused on the health effects of exposure of laboratory animals and humans to different sources of electromagnetic fields such as mobile phones and their base stations, mobile phone jammers, laptop computers, radars, dentistry cavitrons and MRI. Today, substantial evidence indicates that mercury even at low doses may lead to toxicity. Increased release of mercury from dental amalgam fillings after exposure to MRI or microwave radiation emitted by mobile phones has been previously shown by our team. Moreover, our recent studies on the effects of stronger magnetic fields entirely confirmed our previous findings. From the other point of view, we have also shown that papers which reported no increased release of mercury after MRI, may have some methodological flaws. As a strong positive correlation between maternal and cord blood mercury levels has been found in some studies, our findings regarding the effect of exposure to electromagnetic fields on the release of mercury from dental amalgam fillings lead us to this conclusion that pregnant women with dental amalgam fillings should limit their exposure to electromagnetic fields to prevent toxic effects of mercury in their foetuses.

Keywords: pregnancy, foetus, mercury release, dental amalgam, electromagnetic fields, MRI, mobile phones

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Authors: Waleed Aly Sayed Ahmed, Eman Kishk, Tahani Shams

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Aim: To study the effects of co-administration of phosphodiesterase-5 inhibitor (PDE-5) and sodium selenite against the damage induced by ovarian ischemia-reperfusion in rats. Materials and Methods: A total of forty-two sexually mature, virgin, female rats were divided randomly into six groups of seven each: sham group (C), ischemia group (I), ischemia/reperfusion group (I/R), ischemia/reperfusion plus 1.4mg/kg sildenafil (I/R+S) group, ischemia/reperfusion plus 0.2mg/kg selenium (I/R+Se) group and ischemia/reperfusion plus combination of sildenafil and selenium (I/R+S+Se) group. In ischemia group (I), rats were exposed to ischemia for 3 hours (h). In ischemia/reperfusion group (I/R), rats were exposed to ischemia for 3 h followed by 6 h of reperfusion. Treated groups received 1.4mg/kg sildenafil or 0.2 mg/kg selenium or both 30 min before reperfusion. Both ovaries were surgically removed carefully. One ovary was examined for histopathological changes and the other was subject to biochemical analysis including malondialdehyde (MDA), catalase (CAT) and glutathione peroxidase (GPx). Results: Assessment of ovarian tissue damage using a scoring system showed marked vascular congestion, interstitial edema, leukocyte infiltration, hemorrhage, and follicular degeneration in ischemia and ischemia/reperfusion groups. Tissue damage score for I, IR and all treated groups were significantly higher than those of the sham group (p<0.001), while tissue damage score decreased significantly in I/R+S and I/R+Se groups compared to I/R group (p<0.05), and notably, the difference was highly significant in I/R+S+Se group (p<0.001). There was significant increase in MDA levels and reduction in activities of CAT and GPx in I/R group compared to the sham group (p < 0.05). In I/R+S and I/R+Se groups, MDA was significantly decreased compared to the I/R group (p<0.05) and the difference was highly significant with co-administration of sildenafil and selenium (p<0.001). CAT and GPx were higher in all treated groups compared to I/R group (p<0.05). Conclusion: The co-administration of sildenafil citrate and selenium are highly protective against damage induced by ovarian ischemia/reperfusion in rats.

Keywords: phosphodiesterase-5 inhibitor, sildenafil, antioxidant, selenium, ovarian ischemia

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Authors: Toumi Khamari

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This abstract presents an ecolinguistic investigation of the role of language in cultivating environmental consciousness within the Algerian context. Grounded in the field of applied linguistics, this study aims to explore how language shapes perceptions, attitudes, and behaviors related to the environment in Algeria. By examining linguistic practices and discourse patterns, this research sheds light on the potential for language to inspire ecological sustainability and foster environmental awareness. Employing a qualitative research design, the study incorporates discourse analysis and ethnographic methods to analyze language use and its environmental implications. Drawing from Algerian linguistic and cultural contexts, we investigate the unique ways in which language reflects and influences environmental consciousness among Algerian individuals and communities. This research explores the impact of linguistic features, metaphors, and narratives on environmental perceptions, addressing the complex interplay between language, culture, and the natural world. Previous studies have emphasized the significance of language in shaping environmental ideologies and worldviews. In the Algerian context, linguistic representations of nature, such as traditional proverbs and indigenous knowledge, hold immense potential in cultivating a harmonious relationship between humans and the environment. This research delves into the multifaceted connections between language, cultural heritage, and ecological sustainability, aiming to identify linguistic practices that promote environmental stewardship and conservation in Algeria. Furthermore, the study investigates the effectiveness of ecolinguistic interventions tailored to the Algerian context. By examining the impact of eco-education programs, eco-literature, and language-based environmental campaigns, we aim to uncover the potential of language as a catalyst for transformative environmental change. These interventions seek to engage Algerian individuals and communities in dialogue, empowering them to take active roles in environmental advocacy and decision-making processes. Through this research, we contribute to the field of ecolinguistics by shedding light on the Algerian perspective and its implications for environmental consciousness. By understanding the linguistic dynamics at play and leveraging Algeria's rich linguistic heritage, we can foster environmental awareness, encourage sustainable practices, and nurture a deeper appreciation for Algeria's unique ecological landscapes. Ultimately, this research seeks to inspire a collective commitment to environmental stewardship and contribute to the global discourse on language, culture, and the environment.

Keywords: eco-linguistics, environmental consciousness, language and culture, Algeria and North Africa

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Authors: M. G. Ghanem, A. M. M. A. Allam, Diaa E. Fawzy, Mehmet Faruk Cengiz

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This paper is devoted to the design and implementation of a smartwatch textile antenna for Wi-Fi bio-medical applications in millimetric wave bands. The antenna is implemented on a leather textile-based substrate to be embedded in a smartwatch. It enables the watch to pick Wi-Fi signals without the need to be connected to a mobile through Bluetooth. It operates at 60 GHz or WiGig (Wireless Gigabit Alliance) band with a wide band for higher rate applications. It also could be implemented over many stratified layers of the body organisms to be used in the diagnosis of many diseases like diabetes and cancer. The structure is designed and simulated using CST (Studio Suite) program. The wearable patch antenna has an octagon shape, and it is implemented on leather material that acts as a flexible substrate with a size of 5.632 x 6.4 x 2 mm3, a relative permittivity of 2.95, and a loss tangent of 0.006. The feeding is carried out using differential feed (discrete port in CST). The work provides five antenna implementations; antenna without ground, a ground is added at the back of the antenna in order to increase the antenna gain, the substrate dimensions are increased to 15 x 30 mm2 to resemble the real hand watch size, layers of skin and fat are added under the ground of the antenna to study the effect of human body tissues human on the antenna performance. Finally, the whole structure is bent. It is found that the antenna can achieve a simulated peak realized gain in dB of 5.68, 7.28, 6.15, 3.03, and 4.37 for antenna without ground, antenna with the ground, antenna with larger substrate dimensions, antenna with skin and fat, and bent structure, respectively. The antenna with ground exhibits high gain; while adding the human organisms absorption, the gain is degraded because of human absorption. The bent structure contributes to higher gain.

Keywords: bio medical engineering, millimetric wave, smart watch, textile antennas, Wi-Fi

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Authors: Carla Silva

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The aim of this research is to study the relationship between the performance of humanities students in different statistics classes and their performance in their specific courses. Several factors are been studied, such as gender and final grades in statistics and math. Participants of this study comprised a sample of students at a Lisbon University during their academic year. A significant relationship tends to appear between these factors and the performance of these students. However this relationship tends to be stronger with students who had previous studied calculus and math.

Keywords: education, performance, statistic, humanities

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Authors: A. A. Yakub, Omavudu Ikogho

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Land subdivision in most peri-urban areas of Kano metropolis is the entrenched prerogative of ‘KAFADA’ a group of informal plot partitioners who oversee the demarcation of mainly previous farmland into residential plots popularly called 'awon igiya' for those in need. With time these areas are engulfed in the milieu of the rapidly expanding urban landscape and form clusters of poorly planned settlements with tendencies to become future slums. This paper studies the practice of informal land subdivision in Kano metropolis with emphasis on the practitioners, the institutional framework, and the demand and supply scenario that sustains this trend as well as the extent of infrastructural development in these areas. Using three selected informally planned settlements as case-studies, a series of interviews and questionnaires are administered to 'KAFADA,' residents and the state land officers to generate data in these areas. Another set of data was similarly generated in three government subdivided residential layouts, and both sets analysed comparatively. The findings identify varying levels of infrastructural deficits in the informal communities compared to the planned neighbourhoods which are seen to be as a result of the absence of government participation and an informal subdivision process which did not provide for proper planning standards. This study recommends that the regulatory agencies concerned register and partner with KAFADA to ensure that minimal planning standards are maintained in future settlements.

Keywords: peri-urban, informal land markets, land subdivision, infrastructure

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Authors: Shweh Fern Loo, Jun Yin Ong, Than Zaw Oo

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Acute respiratory distress syndrome (ARDS) is a common serious condition of bilateral lung infiltrates that develops secondary to various underlying conditions such as diseases or injuries. ARDS with severe hypercapnia is associated with higher ICU mortality and morbidity. Venovenous Extracorporeal membrane oxygenation (VV-ECMO) support has been established to avert life-threatening hypoxemia and hypercapnic respiratory failure despite optimal conventional mechanical ventilation. However, VV-ECMO is relatively not advisable in particular groups of patients, especially in multi-organ failure, advanced age, hemorrhagic complications and irreversible central nervous system pathology. We presented a case of a 79-year-old Chinese lady without any pre-existing lung disease admitted to our hospital intensive care unit (ICU) after acute presentation of breathlessness and chest pain. After extensive workup, she was diagnosed with rapidly progressing acute interstitial pneumonia with ARDS and hypercapnia respiratory failure. The patient received lung protective strategies of mechanical ventilation and neuromuscular blockage therapy as per clinical guidelines. However, hypercapnia respiratory failure was refractory, and she was deemed not a good candidate for VV-ECMO support given her advanced age and high vasopressor requirements from shock. Alternative therapy with extracorporeal CO2 removal (ECCO2R) was considered and implemented. The patient received 12 days of ECCO2R paired with muscle paralysis, optimization of lung-protective mechanical ventilation and dialysis. Unfortunately, the patient still had refractory hypercapnic respiratory failure with dual vasopressor support despite prolonged therapy. Given failed and futile medical treatment, the family opted for withdrawal of care, a conservative approach, and comfort care, which led to her demise. The effectivity of extracorporeal CO2 removal may depend on disease burden, involvement and severity of the disease. There is insufficient data to make strong recommendations about its benefit-risk ratio for ECCO2R devices, and further studies and data would be required. Nonetheless, ECCO2R can be considered an alternative treatment for refractory hypercapnic respiratory failure patients who are unsuitable for initiating venovenous ECMO.

Keywords: extracorporeal CO2 removal (ECCO2R), acute respiratory distress syndrome (ARDS), acute interstitial pneumonia (AIP), hypercapnic respiratory failure

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Authors: Boularas El-Alia, Arbi Raja, Bachir Bouiadjra Sara, Rezk-Kallah Haciba, Rezkkallah Baghdad

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Objectives : To determine the handling practices of cytotoxic drugs and to describe clinical manifestations expressed by hospital personnel of Sidi Bel Abbes during the year 2014. Methods: Sectional descriptive study conducted in 3 center university hospital units (Hematology, Oncology and Urology) and Gynecology of EHS Sidi Bel Abbes. A questionnaire was administered to hospital workers regulary exposed to cytotoxic drugs. A work-place visit was performed to have an overview about working conditions. The Cytotoxic Contact Index (CCI) was calculated for each nurse on a period of 15 working days. Treatment of the results was done using SPSS software. Results: The survey reveals that 22 men and 58 women are exposed to cytotoxic drugs for an average of 7 years. Many symptoms such as ocular irritation (38,75%), throat irritation (56,25%), headache (68,75%), dizziness (43,75%), nausea (37,5%), metallic taste (30%), were reported with high frequency. Are noted in the offspring, 3 congenital anomalies,2 diaphragmatic hernia and a cleft palate. The Cytotoxic Contact Index (CCI) was higher than 3 among Oncology nurses and higher than 1 for most of the nurses of Hematology and Gynecology service. The wearing of personal protective clothing was not respected by all workers: (22/23) wear gloves and (20/23) wear a mask,(5/23) wear a cap, (2/23) wear glasses. Only 3 nurses have benefited from continuous training on handling cytotoxic drugs. Conclusion: This study shows a high occupational exposure risk to cytotoxic drugs among persons handling these drugs and the necessity to apply rigorously all measures related to personal protection awareness and training of personnel to minimize these exposure.

Keywords: cytotoxic drugs, handling, clinical manifestations, hospital staff

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Authors: Heesuk Seo, Yongtae Kim

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Online learning started in the 1990s, the spread of the Internet has been through the era of e-learning paradigm of online education in the era of smart learning change. Reflecting the different nature of the mobile to anywhere anytime, anywhere was also allows the form of learning, it was also available through the learning content and interaction. We are developing a cloud system, 'TLINKS CLOUD' that allows you to configure the environment of the smart learning without the need for additional infrastructure. Using the big-data analysis for e-learning contents, we provide an integrated solution for e-learning tailored to individual study.

Keywords: authority tool, big data analysis, e-learning, HTML5

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Authors: Ali Kassem

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Background: In the last few years, factors such as insulin resistance (IR) and hepatic steatosis have been linked to progression of hepatic fibrosis.Patients with chronic liver disease, and cirrhosis in particular, are known to be prone to IR. However, chronic HCV (hepatitis C) infection may induce IR, regardless of the presence of liver cirrhosis. Our aims are to study insulin resistance (IR) assessed by HOMA-IR (Homeostatic Model Assessment Insulin Resistance) as a possible risk factor in disease progression in cirrhotic patients and to evaluate the role of IR in hepatic fibrosis progression. The correlations of HOMA-IR values to laboratory, virological and histopathological parameters of chronic HCV are also examined. Methods: The study included 50 people divided into 30 adult chronic hepatitis C patients diagnosed by PCR (polymerase chain reaction) within previous 6 months and 20 healthy controls. The functional and morphological status of the liver were evaluated by ultrasonography and laboratory investigations including liver function tests and by liver biopsy. Fasting blood glucose and fasting insulin levels were measured and body mass index and insulin resistance were calculated. Patients having HOMA-IR >2.5 were labeled as insulin resistant. Results: Chronic hepatitis C patients with IR showed significantly higher mean values of BMI (body mass index) and fasting insulin than those without IR (P < 0.000). Patients with IR were more likely to have steatosis (p = 0.006), higher necroinflammatory activity (p = 0.05). No significant differences were found between the two groups regarding hepatic fibrosis. Conclusion: HOMA-IR measurement could represent a novel marker to identify the cirrhotic patients at greater risk for the progression of liver disease. As IR is a potentially modifiable risk factor, these findings may have important prognostic and therapeutic implications. Assessment of IR by HOMA-IR and improving insulin sensitivity are recommended in patients with HCV and related chronic liver disease.

Keywords: hepatic fibrosis, hepatitis C virus infection, hepatic steatosis, insulin resistance

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Authors: Osakwe Jude Odiakaosa

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Today’s digital society is characterized by e-education or e-learning, e-commerce, and so on. All these have been propelled by digital revolution. Digital technology such as computer technology, Global Positioning System (GPS) and Geographic Information System (GIS) has been having a tremendous impact on the field of technology. This development has positively affected the scope, methods, speed of data acquisition, data management and the rate of delivery of the results (map and other map products) of data processing. This paper tries to address the impact of revolution brought by digital technology.

Keywords: digital revolution, internet, technology, data management

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Authors: Iva Buchberger, Vesna Kovač

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Global education policy trends and recommendations underline the importance of (distributive) school leadership as a school effectiveness key factor. In this context, the broader aim of this research (supported by the Croatian Science Foundation) is to identify school leadership characteristics in Croatian schools and to examine the correlation between school leadership and school effectiveness. The aim of the proposed conference paper is to focus on the school leadership characteristics which are additionally explained with school leadership facilitators that contribute to (distributive) school leadership development. The aforementioned school leadership characteristics include the following dimensions: (a) participation in the process of making different types of decisions, (b) influence in the decision making process, (c) social interactions between different stakeholders in the decision making process in schools. Further, the school leadership facilitators are categorized as follows: (a) principal’s activities (such as providing support to different stakeholders and developing mutual trust among them), (b) stakeholders’ characteristics (such as developed stakeholders’ interest and competence to participate in decision-making process), (c) organizational and material resources (such as school material conditions, the necessary information and time as resources for making decisions). The data were collected by a constructed and validated questionnaire for examining the school leadership characteristics and facilitators from teachers’ perspective. The main population in this study consists of all primary schools in Croatia while the sample is comprised of 100 primary schools, selected by random sampling. Furthermore, the sample of teachers was selected by an additional procedure taking into consideration the independent variables of sex, work experience, etc. Data processing was performed by standard statistical methods of descriptive and inferential statistics. Statistical program IBM SPSS 20.0 was used for data processing. The results of this study show that there is a (positive) correlation between school leadership characteristics and school leadership facilitators. Specifically, it is noteworthy to mention that all the dimensions of school leadership characteristics are in positive correlation with the categories of school leadership facilitators. These results are indicative for the education policy creators who should ensure positive and supportive environment for the school leadership development including the development of school leadership characteristics and school leadership facilitators.

Keywords: distributive school leadership, school effectiveness , school leadership characteristics, school leadership facilitators

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Authors: J. Subbalakshmi, G. Dhruvasamhith, S. M. Hussain

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Polyaniline (PANI) is one of the most extensively studied material among the conducting polymers due to its simple synthesis by chemical and electrochemical routes. PANIs have advantages of chemical stability and high conductivity making their commercial applications quite attractive. However, to our knowledge, very little work has been reported on the tensile strength properties of templated PANIs processed with polyvinyl alcohol and also, detailed study has not been carried out. We have investigated the effect of small molecule and polymers as templates on PANI. Stable aqueous colloidal suspensions of trisodium citrate (TSC), poly(ethylenedioxythiophene)-polystyrene sulfonate (PEDOT-PSS), and polyethylene glycol (PEG) templated PANIs were prepared through chemical synthesis, processed with polyvinyl alcohol (PVA) and were fabricated into films by solution casting. Absorption and infra-red spectra were studied to gain insight into the possible molecular interactions. Surface morphology was studied through scanning electron microscope and optical microscope. Interestingly, tensile testing studies revealed least strain for pure PVA when compared to the blends of templated PANI. Furthermore, among the blends, TSC templated PANI possessed maximum elasticity. The ultimate tensile strength for PVA processed, PEG-templated PANI was found to be five times more than other blends considered in this study. We establish structure–property correlation with morphology, spectral characterization and tensile testing studies.

Keywords: surface morphology, processed films, polyvinyl alcohol, templated polyanilines, tensile testing

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Authors: Azadeh Mottaghi, Zeynab Shakeri

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Background: Eating disorders (ED) are group of psychological disorders that significantly impair physical health and psychosocial function. EDconsists wide range of morbidity such as loss of eating control, binge eating disorder(BED), night eating syndrome (NES), and bulimia nervosa. Eating behavior is a wide range term that includes food choices, eating patterns, eating problems. In this study, current knowledge will be discussed aboutcomparison of eating disorders and eating behaviors in morbid obese women with and without type 2 diabetes. Methods: 231 womenwith morbid obesity were included in the study.Loss of eating control, Binge eating disorder and Bulimia nervosa, Night eating syndrome, and eating behaviors and psychosocial factorswere assessed. SPSS version 20 was used for statistical analysis. A p-value of <0.05 was considered significant. Results: There was a significant difference between women with and without diabetes in case of binge eating disorder (76.3% vs. 47.3%, p=0.001). Women with the least Interpersonal support evaluation list (ISEL) scores had a higher risk of eating disorders, and it is more common among diabetics (29.31% vs. 30.45%, p= 0.050). There was no significant difference between depression level and BDI score among women with or without diabetes. Although 38.5% (n=56) of women with diabetes and 50% (n=71) of women without diabetes had minimal depression. The logistic regression model has shown that women without diabetes had lower odds of exhibiting BED (OR=0.28, 95% CI 0.142-0.552).Women with and without diabetes with high school degree (OR=5.54, 95% CI 2.46-9.45, P= 0.0001 & OR=6.52, 95% CI 3.15-10.56, respectively) and moderate depression level (OR=2.03, 95% CI 0.98-3.95 & OR=3.12, 95% CI 2.12-4.56, P= 0.0001) had higher odds of BED. Conclusion: The result of the present study shows that the odds of BED was lower in non-diabetic women with morbid obesity. Women with morbid obesity who had high school degree and moderate depression level had more odds for BED.

Keywords: eating disorders binge eating disorder, night eating syndrome, bulimia nervosa, morbid obesity

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Authors: Essam Mansour

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The key purpose of this study is to show information-seeking behaviour of Kuwaiti Judges (KJs). Being one of the few studies about the information needs and information-seeking behaviour conducted in Arab and developing countries, this study is a pioneer one among many studies conducted in information seeking, especially with this significant group of information users. The authors tried to investigate this seeking behavior in terms of KJs' thoughts, perceptions, motivations, techniques, preferences, tools and barriers met when seeking information. The authors employed a questionnaire, with a response rate 77.2 percent. This study showed that most of KJs were likely to be older, educated and with a work experience ranged from new to old experience. There is a statistically reliable significant difference between KJs' demographic characteristics and some sources of information, such as books, encyclopedias, references and mass media. KJs were using information moderately to make a decision, to be in line with current events, to collect statistics and to make a specific/general research. The office and home were the most frequent location KJs were accessing information from. KJs' efficiency level of the English language is described to be moderately good, and a little number of them confirmed that their efficiency level of French was not bad. The assistance provided by colleagues, followed by consultants, translators, sectaries and librarians were found to be most strong types of assistance needed when seeking information. Mobile apps, followed by PCs, information networks (the Internet) and information databases were the highest technology tool used by KJs. Printed materials, followed by non-printed and audiovisual materials were the most preferred information formats KJs use. The use of languages, the recency of information and the place of information, the deficit role of the library to deliver information were at least significant barriers to KJs when seeking information.

Keywords: information users, information-seeking behaviour, information needs, judges, Kuwait

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Authors: Sofia N. Gonçalves, Duarte M. S. Albuquerque, José C. F. Pereira

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Microwave technology has been gaining importance in contributing to decarbonization processes in high energy demand industries. Despite the several numerical models presented in the literature, a proper Verification and Validation exercise is still lacking. This is important and required to evaluate the physical process model accuracy and adequacy. Another issue addresses impedance matching, which is an important mechanism used in microwave experiments to increase electromagnetic efficiency. Such mechanism is not available in current computational tools, thus requiring an external numerical procedure. A numerical model was implemented to study the continuous processing of limestone with microwave heating. This process requires the material to be heated until a certain temperature that will prompt a highly endothermic reaction. Both a 2D and 3D model were built in COMSOL Multiphysics to solve the two-way coupling between Maxwell and Energy equations, along with the coupling between both heat transfer phenomena and limestone endothermic reaction. The 2D model was used to study and evaluate the required numerical procedure, being also a benchmark test, allowing other authors to implement impedance matching procedures. To achieve this goal, a controller built in MATLAB was used to continuously matching the cavity impedance and predicting the required energy for the system, thus successfully avoiding energy inefficiencies. The 3D model reproduces realistic results and therefore supports the main conclusions of this work. Limestone was modeled as a continuous flow under the transport of concentrated species, whose material and kinetics properties were taken from literature. Verification and Validation of the coupled model was taken separately from the chemical kinetic model. The chemical kinetic model was found to correctly describe the chosen kinetic equation by comparing numerical results with experimental data. A solution verification was made for the electromagnetic interface, where second order and fourth order accurate schemes were found for linear and quadratic elements, respectively, with numerical uncertainty lower than 0.03%. Regarding the coupled model, it was demonstrated that the numerical error would diverge for the heat transfer interface with the mapped mesh. Results showed numerical stability for the triangular mesh, and the numerical uncertainty was less than 0.1%. This study evaluated limestone velocity, heat transfer, and load influence on thermal decomposition and overall process efficiency. The velocity and heat transfer coefficient were studied with the 2D model, while different loads of material were studied with the 3D model. Both models demonstrated to be highly unstable when solving non-linear temperature distributions. High velocity flows exhibited propensity to thermal runways, and the thermal efficiency showed the tendency to stabilize for the higher velocities and higher filling ratio. Microwave efficiency denoted an optimal velocity for each heat transfer coefficient, pointing out that electromagnetic efficiency is a consequence of energy distribution uniformity. The 3D results indicated the inefficient development of the electric field for low filling ratios. Thermal efficiencies higher than 90% were found for the higher loads and microwave efficiencies up to 75% were accomplished. The 80% fill ratio was demonstrated to be the optimal load with an associated global efficiency of 70%.

Keywords: multiphysics modeling, microwave heating, verification and validation, endothermic reactions modeling, impedance matching, limestone continuous processing

Procedia PDF Downloads 128