Search results for: Hartree-Fock method

Authors: Ashokkumar Subbiah

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This study investigates the impact of factors that influenced the success of construction planning for a major construction project in Qatar. An approach of participant observation is adopted which is informed by the principles of ethnography: one that reports the participants’ view of their world rather than imposing an artificial theoretical framework upon it. As participant observant, key factors were observed and identified that had an impact on the management and execution of the construction planning. It is found that a ‘shadow culture’ exists between the project participants which, it is argued, is only observable from the perspective of an embedded participant observer. The shadow culture acts to enable the management of the planning process, and its efficacy relates to the ‘quality’ of human inter-relationships amongst immediate stakeholders. Whilst this study uses the concept of shadow culture, it is treated as both a methodological stance and one of the findings of this research in the context of the major construction project in Qatar. The concept of shadow culture is not imposed upon the findings, but instead is used as a research tool: respondents report their own worldview and this is reported from the view of a participant observant in a manner that is understandable and useful to those who are not part of the construction project. The findings of this study identify similar factors influencing the planning process of the Qatar project, but the shadow culture predominantly influences these factors towards the failure of planning process. The research concludes by questioning the assumption that construction planning is a mechanistic process that has to be conducted solely by the planning team. Instead, it is a highly social phenomenon in which the seemingly mechanistic process is made workable by the quality of relationships that exist in the project. Drawing on this the final section provides a series of recommendations that may be helpful in enhancing the efficacy of project planning; these include better training/education at the pre-construction phase; recognition of the importance of shadow processes at management levels, and better appreciation of the impact of contract type and chosen procurement route.

Keywords: construction planning, participant observation, project participants, shadow culture

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Authors: Smriti, Ajeet Kumar

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We present a variant of the Irving-Kirkwood procedure to obtain the microscopic expressions of the cross-section averaged continuum fields such as internal force and moment in one-dimensional nanostructures in the non-equilibrium setting. In one-dimensional continuum theories for slender bodies, we deal with quantities such as mass, linear momentum, angular momentum, and strain energy densities, all defined per unit length. These quantities are obtained by integrating the corresponding pointwise (per unit volume) quantities over the cross-section of the slender body. However, no well-defined cross-section exists for these nanostructures at finite temperature. We thus define the cross-section of a nanorod to be an infinite plane which is fixed in space even when time progresses and defines the above continuum quantities by integrating the pointwise microscopic quantities over this infinite plane. The method yields explicit expressions of both the potential and kinetic parts of the above quantities. We further specialize in these expressions for helically repeating one-dimensional nanostructures in order to use them in molecular dynamics study of extension, torsion, and bending of such nanostructures. As, the Irving-Kirkwood procedure does not yield expressions of stiffnesses, we resort to a thermodynamic equilibrium approach to obtain the expressions of axial force, twisting moment, bending moment, and the associated stiffnesses by taking the first and second derivatives of the Helmholtz free energy with respect to conjugate strain measures. The equilibrium approach yields expressions independent of kinetic terms. We then establish the equivalence of the expressions obtained using the two approaches. The derived expressions are used to understand the extension, torsion, and bending of single-walled carbon nanotubes at non-zero temperatures.

Keywords: thermoelasticity, molecular dynamics, one dimensional nanostructures, nanotube buckling

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Authors: Abdela Bulbula

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Background: Marek’s disease virus is a devastating infection, causing high morbidity and mortality in chickens in Ethiopia. Methods: The current study was conducted from March to November, 2021 with the general objective of performing antemortem and postmortem, isolation, and molecular detection of Marek’s disease virus from outbreak cases in southwestern Ethiopia. Accordingly, based on outbreak information reported from the study sites namely, Bedelle, Yayo, and Bonga towns in southwestern Ethiopia, 50 sick chickens were sampled. The backyard and intensive farming systems of chickens were included in the sampling and priorities were given for chickens that showed clinical signs that are characteristics of Marek’s disease. Results: By clinical examinations, paralysis of legs and wings, gray eye, loss of weight, difficulty in breathing, and depression were recorded on all chickens sampled for this study and death of diseased chickens was observed. In addition, enlargement of the spleen and gross lesions of the liver and heart were recorded during postmortem examination. The death of infected chickens was observed in both vaccinated and non-vaccinated flocks. Out of 50 pooled feather follicle samples, Marek’s disease virus was isolated from 14/50 (28%) by cell culture method and out of six tissue samples, the virus was isolated from 5/6(83.30%). By Real time polymerization chain reaction technique, which was targeted to detect the Meq gene, Marek’s disease virus was detected from 18/50 feather follicles which accounts for 36% of sampled chickens. Conclusion: In general, the current study showed that the circulating Marek’s disease virus in southwestern Ethiopia was caused by the oncogenic Gallid herpesvirus-2 (Serotype-1). Further research on molecular characterization of revolving virus in current and other regions is recommended for effective control of the disease through vaccination.

Keywords: Ethioi, Marek's disease, isolation, molecular

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Authors: Philippa Hunter

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How might history education support teachers and students to see the past as a provocation, be open to possible futures, and act differently? As teacher educators in an age of diversity and uncertainty, we need to question history’s curriculum nature, pedagogy, and policy intent. The cultural politics of history’s identity in the senior secondary curriculum influences educational socialization (disciplinary, professional, research) and engagement with curriculum decision-making. This paper reflects on curriculum disturbance that shaped a critical pedagogy stance to problematize school history’s certainties. The context is situated in an Aotearoa New Zealand university-based initial teacher education programme. A pedagogic innovation was activated whereby problematized history pedagogy [PHP] was conceptualized as the phenomenon and method of inquiry and storied in doctoral work. The PHP was a reciprocal research process involving history class’ participants and the teacher as researcher, in fashioning teaching identities, identifying with, and thinking critically about history pedagogy. PHP findings revealed evocative discourses of embodiment, nostalgia, and connectedness about living ‘inside the past’. Participants expressed certainty about their abilities as teachers living ‘outside the past’ to interpret historical perspectives. However, discomfort was evident in relation to ‘difficult knowledge’ or unfamiliar contexts of the past that exposed exclusion, powerlessness, or silenced voices. Participants identified history programmes as strongly masculine and conflict-focused. A normalized inquiry-transmission approach to history pedagogy was identified and critiqued. Individuals’ reflexive accounts of PHP implemented whilst on practicum indicate possibilities of history pedagogy as; inclusive and democratic, social and ethical reconstruction, and as a critical project. The PHP sought to reimagine history curriculum and identify spaces of possibility in secondary postgraduate teacher education.

Keywords: curriculum, pedagogy, problematise, reciprocal

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Authors: Ting Shen, Spyros Konstantopoulos

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During the past three decades, class size effects have been a focal debate in education. The idea of having smaller class is enormously popular among parents, teachers and policy makers. The rationale of its popularity is that small classroom could provide a better learning environment in which there would be more teacher-pupil interaction and more individualized instruction. This early stage benefits would also have a long-term positive effect. It is a common belief that reducing class size may result in increases in student achievement. However, the empirical evidence about class-size effects from experimental or quasi-experimental studies has been mixed overall. This study sheds more light on whether class size reduction impacts reading achievement in eight European countries: Bulgaria, Germany, Hungary, Italy, Lithuania, Romania, Slovakia, and Slovenia. We examine class size effects on reading achievement using national probability samples of fourth graders. All eight European countries had participated in the Progress in International Reading Literacy Study (PIRLS) in 2001, 2006 and 2011. Methodologically, the quasi-experimental method of instrumental variables (IV) has been utilized to facilitate causal inference of class size effects. Overall, the results indicate that class size effects on reading achievement are not significant across countries and years. However, class size effects are evident in Romania where reducing class size increases reading achievement. In contrast, in Germany, increasing class size seems to increase reading achievement. In future work, it would be valuable to evaluate differential class size effects for minority or economically disadvantaged student groups or low- and high-achievers. Replication studies with different samples and in various settings would also be informative. Future research should continue examining class size effects in different age groups and countries using rich international databases.

Keywords: class size, reading achievement, instrumental variables, PIRLS

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Authors: Warda Jabeen, Romaisa Shamim Khan, Osama Shakeel, Ahmed Faraz Bhatti, Raza Hussain

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Background: The worldwide incidence of cutaneous melanoma (CM) has been on the rise over the past few decades. Primary prevention and early treatment remain the focus of management to reduce the burden of disease. This entails identification of risk factors to prompt early diagnosis. In Pakistan, there is a scarcity of clinico-pathological data relating to cutaneous malignant melanoma. Objective: The purpose of this study was to analyze the epidemiological and clinical characteristics of patients presenting with cutaneous malignant melanoma in Pakistan, and to compare the results with other studies. Method: Shaukat Khanum Memorial Cancer Hospital and Research Centre is currently the only dedicated cancer hospital in the country, accepting patients from all over Pakistan. Majority of the patients, however, belong to the northern half of the country. From the recorded data of the hospital, all cutaneous melanoma cases were identified and evaluated. Results: Between 1997 and 2017, a total of 169 cutaneous melanoma patients were registered at Shaukat Khanum. Mean age was 47.5 years. The highest incidence of melanoma was seen in the age group 40-59 years (n=69, 40.8%). Most commonly reported clinical subtype was unspecified melanoma (n=154, 91%). Amongst those in which T stage was reported, the most frequently observed T-stage at presentation was T4 (n=23, 13.6%). With regards to body distribution, in our study CM was seen most commonly in the lower limb including the hip. The yearly incidence of melanoma has increased/remained stable from 2007 to 2017. Conclusion: cutaneous malignant melanoma is a fairly common disease in Pakistan. Patients tend to present at a more advanced stage as compared to patients in developed countries. Identification of risk factors and tumor characteristics is therefore of paramount importance to deal with these patients.

Keywords: epidemiology of cutaneous malignant melanoma, cutaneous malignant melanoma, Pakistan, skin cancer

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Authors: S. B. D. Samarasinghe, Malini Herath

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Participatory planning is a very important process for decision making and choosing the best alternative options for community welfare, development of the society and its interactions among community and professionals. People’s involvement is considered as the key guidance in participatory planning. Presently, Participatory planning is being used in many fields. It's not only limited to planning but also to disaster management, poverty, housing, etc. In the past, Disaster management practice was a top-down approach, but it raised many issues as it was converted to a bottom-up approach. There are several approaches that can aid disaster management. Community-Based Disaster Risk Management (CBDRM) is a very successful participatory approach to risk management that is often successfully applied by other disaster-prone countries. In the local context, CBDRM has been applied to prevent Diseases as well as to prevent disasters such as landslides, tsunamis and floods. From three years before, Sri Lanka has initiated the CBDRM approach to minimize landslide vulnerability. Hence, this study mainly focuses on the impact of CBDRM approaches on landslide hazards. Also to identify their successes and failures from both implementing parties and community. This research is carried out based on a qualitative method combined with a descriptive research approach. A successful framework was prepared via a literature review. Case studies were selected considering landslide CBDRM programs which were implemented by Disaster Management Center and National Building Research Organization in Badulla. Their processes were evaluated. Data collection is done through interviews and informal discussions. Then their ideas were quantified by using the Relative Effectiveness index. The resulting numerical value was used to rank the program effectiveness and their success, failures and impacting factors. Results show that there are several failures among implementing parties and the community. Overcoming those factors can make way for better conduction of future CBDRM programs.

Keywords: community-based disaster risk management, disaster management, preparedness, landslide

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Authors: Kanupriya Rawat, Aleksandra Błachnio, Paweł Izdebski

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Achievement motivation, which drives a person to strive for success, is an important construct in sports psychology. This systematic review aims to analyze the methods of measuring achievement motivation used in previous studies published over the past four decades and to find out which method of measuring achievement motivation is the most prevalent and the most effective by thoroughly examining measures of achievement motivation used in each study and by evaluating most highly cited achievement motivation measures in sport. In order to understand this latent construct, thorough measurement is necessary, hence a critical evaluation of measurement tools is required. The literature search was conducted in the following databases: EBSCO, MEDLINE, APA PsychARTICLES, Academic Search Ultimate, Open Dissertations, ERIC, Science direct, Web of Science, as well as Wiley Online Library. A total of 26 articles met the inclusion criteria and were selected. From this review, it was found that the Achievement Goal Questionnaire- Sport (AGQ-Sport) and the Task and Ego Orientation in Sport Questionnaire (TEOSQ) were used in most of the research, however, the average weighted impact factor of the Achievement Goal Questionnaire- Sport (AGQ-Sport) is the second highest and most relevant in terms of research articles related to the sport psychology discipline. Task and Ego Orientation in Sport Questionnaire (TEOSQ) is highly popular in cross-cultural adaptation but has the second last average IF among other scales due to the less impact factor of most of the publishing journals. All measures of achievement motivation have Cronbach’s alpha value of more than .70, which is acceptable. The advantages and limitations of each measurement tool are discussed, and the distinction between using implicit and explicit measures of achievement motivation is explained. Overall, both implicit and explicit measures of achievement motivation have different conceptualizations of achievement motivation and are applicable at either the contextual or situational level. The conceptualization and degree of applicability are perhaps the most crucial factors for researchers choosing a questionnaire, even though they differ in their development, reliability, and use.

Keywords: achievement motivation, task and ego orientation, sports psychology, measures of achievement motivation

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Authors: Sneha Kumari, Ravi Krishnan Elangovan

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This abstract describes the development of a high-speed tracking method by modification in motor components for nanoparticle attachment. Myosin motors are nano-sized protein machines powering movement that defines life. These miniature molecular devices serve as engines utilizing chemical energy stored in ATP to produce useful mechanical energy in the form of a few nanometre displacement events leading to force generation that is required for cargo transport, cell division, cell locomotion, translated to macroscopic movements like running etc. With the advent of in vitro motility assay (IVMA), detailed functional studies of the actomyosin system could be performed. The major challenge with the currently available IVMA for tracking actin filaments is a resolution limitation of ± 50nm. To overcome this, we are trying to develop Single Molecule IVMA in which nanoparticle (GNP/QD) will be attached along or on the barbed end of actin filaments using CapZ protein and visualization by a compact TIRF module called ‘cTIRF’. The waveguide-based illumination by cTIRF offers a unique separation of excitation and collection optics, enabling imaging by scattering without emission filters. So, this technology is well equipped to perform tracking with high precision in temporal resolution of 2ms with significantly improved SNR by 100-fold as compared to conventional TIRF. Also, the nanoparticles (QD/GNP) attached to actin filament act as a point source of light coffering ease in filament tracking compared to conventional manual tracking. Moreover, the attachment of cargo (QD/GNP) to the thin filament paves the way for various nano-technological applications through their transportation to different predetermined locations on the chip

Keywords: actin, cargo, IVMA, myosin motors and single-molecule system

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Authors: B. L. Avanthi Isaka, P. G. Ranjith

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The development of technically-sound enhanced geothermal systems (EGSs) is identified as a viable solution for world growing energy demand with immense potential, low carbon dioxide emission and importantly, as an environmentally friendly option for renewable energy production. The use of supercritical carbon dioxide (ScCO₂) as the working fluid in EGSs by replacing traditional water-based method is promising due to multiple advantages prevail in ScCO₂-injection for underground reservoir stimulation. The evolution of reservoir stimulation using ScCO₂ and the understanding of the flow behavior of a ScCO₂-stimulated geothermal reservoir is vital in applying ScCO₂-EGSs as a replacement for water-based EGSs. The study is therefore aimed to investigate the flow behavior of a ScCO₂-fractured rock medium at in-situ stress and temperature conditions. A series of permeability tests were conducted for ScCO₂ fractured Harcourt granite rock specimens at 90ºC, under varying confining pressures from 5–60 MPa using the high-pressure and high-temperature tri-axial set up which can simulate deep geological conditions. The permeability of the ScCO₂-fractured rock specimens was compared with that of water-fractured rock specimens. The results show that the permeability of the ScCO₂-fractured rock specimens is one order higher than that of water-fractured rock specimens and the permeability exhibits a non-linear reduction with increasing confining pressure due to the stress-induced fracture closure. Further, the enhanced permeability of the ScCO₂-induced fracture with multiple secondary branches was explained by exploring the CT images of the rock specimens. However, a single plain fracture was induced under water-based fracturing.

Keywords: supercritical carbon dioxide, fracture permeability, granite, enhanced geothermal systems

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Authors: L. Freeman, D. Bax, V. K. Sapong

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Community-based, preventative approaches to violent extremism may be effective and yet remain an underutilised method. In a realm where security approaches dominate, with the focus on countering violence extremism and combatting radicalisation, community resilience programming remains sparse. This paper will present a survey tool that aims to measure the risk and protective factors that can lead to violent extremism in Mozambique and Tanzania. Conducted in four districts in the Cabo Delgado region of Mozambique and one district in Pwani, Tanzania, the survey uses a combination of BRAVE-14, Afrocentric and context-specific questions in order to more fully understand community resilience opportunities and challenges in preventing and countering violent extremism. Developed in Australia and Canada to measure radicalisation risks in individuals and communities, BRAVE-14 is a tool not yet applied in the African continent. Given the emerging threat of Islamic extremism in Northern Mozambique and Eastern Tanzania, which both experience a combination of socio-political exclusion, resource marginalisation and religious/ideological motivations, the development of the survey is timely and fills a much-needed information gap in these regions. Not only have these Islamist groups succeeded in tapping into the grievances of communities by radicalising and recruiting individuals, but their presence in these regions has been characterised by extreme forms of violence, leaving isolated communities vulnerable to attack. The expected result of these findings will facilitate the contextualisation and comparison of the protective and risk factors that inhibit or promote the radicalisation of the youth in these communities. In identifying sources of resilience and vulnerability, this study emphasises the implementation of context-specific intervention programming and provides a strong research tool for understanding youth and community resilience to violent extremism.

Keywords: community resilience, Mozambique, preventing violent extremism, radicalisation, Tanzania

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Authors: Mindaugas Liaudanskas, Monika Tallat-Kelpsaite, Darius Kviklys, Jonas Viskelis, Pranas Viskelis, Norbertas Uselis, Juozas Lanauskas, Valdimaras Janulis

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Apples are an important source of various biologically active compounds used for human health. Phenolic compounds detected in apples are natural antioxidants and have antimicrobial, anti-inflammatory, anticarcinogenic, and cardiovascular protective activity. The quantitative composition of phenolic compounds in apples may be affected by various factors. It is important to investigate it in order to provide the consumer with high-quality well-known composition apples and products made out of it. The objective of this study was to evaluate phenolic compounds quantitative composition in apple fruits grown in a different geographical region. In this study, biological replicates of apple cv. 'Ligol', grown in Lithuania, Latvia, Poland, and Estonia, were investigated. Three biological replicates were analyzed; one of each contained 10 apples. Samples of lyophilized apple fruits were extracted with 70% ethanol (v/v) for 20 min at 40∘C temperature using the ultrasonic bath. The ethanol extracts of apple fruits were analyzed by the high-performance liquid chromatography method. The study found that the geographical location of apple-trees had an impact on the composition of phenolic compounds in apples. The number of quercetin glycosides varied from 314.78±9.47 µg/g (Poland) to 648.17±5.61 µg/g (Estonia). The same trend was also observed with flavan-3-ols (from 829.56±47.17 µg/g to 2300.85±35.49 µg/g), phloridzin (from 55.29±1.7 µg/g to 208.78±0.35 µg/g), and chlorogenic acid (from 501.39±28.84 µg/g to 1704.35±22.65 µg/g). It was observed that the amount of investigated phenolic compounds tended to increase from apples grown in the southern location (Poland) (1701.02±75.38 µg/g) to apples grown northern location (Estonia) (4862.15±56.37 µg/g). Apples (cv. 'Ligol') grown in Estonia accumulated approx. 2.86 times higher amount of phenolic compounds than apples grown in Poland. Acknowledgment: This work was supported by a grant from the Research Council of Lithuania, project No. S-MIP-17-8.

Keywords: apples, cultivar 'Ligol', geographical regions, HPLC, phenolic compounds

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Authors: Homa Hedayat

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Public spaces have been a central concern of urban planners for centuries but have been neglected for a long time. In the modernist planning, the focus has been on the requirements of cars rather than the needs and expectations of pedestrians, and therefore, cities have lost many qualities. Urban public space is a space within the city area which is accessible to all people and is the ground for their activity. People’s public life occurs in urban public spaces in a complex set of forms and functions. These spaces must facilitate diverse behavior, uses, and activities such as shopping, walking, conversation, entertainment, relaxation or even passing the time during festivities and events. One of the public spaces is the surrounding space of public transportation stations. Subway stations, although potentially encompass many different groups of people accommodate few social interactions. Making the surrounding areas of subway stations pedestrian-oriented, potentially increases the socialization capacity. The Sadeghieh Subway Station can be considered as the most important subway station in Tehran, which on the one hand is the rail port of Tehran's western entrance, and on the other is the port for railway journeys inside the city. The main concern of this study is to assess the success or failure of the interventions made by the municipality for changing the surrounding area of the Sadeghieh Subway Station into a pedestrian-oriented space and examine the amount of the area's improvement into a desirable space. The method used in this study is surveying, in which the data were collected using a questionnaire and interview. The study's population is all people who use Sadeghieh Subway, and the sample size for the study was 140 subjects. Using parametric one-sample t-test, we found improvement in factors such as transportation, security, pedestrian infrastructure, vitality and climate comfort. However, there was no improvement in mix use, recreational activity, readability.

Keywords: public space, public transportation stations, pedestrian-oriented space, socialization

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Authors: Harish Aryal

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The safe and reliable operation of nuclear reactors has always been one of the topmost priorities in the nuclear industry. Transient testing allows us to understand the time-dependent behavior of the neutron population in response to either a planned change in the reactor conditions or unplanned circumstances. These unforeseen conditions might occur due to sudden reactivity insertions, feedback, power excursions, instabilities, and accidents. To study such behavior, we need transient testing, which is like car crash testing, to estimate the durability and strength of a car design. In nuclear designs, such transient testing can simulate a wide range of accidents due to sudden reactivity insertions and helps to study the feasibility and integrity of the fuel to be used in certain reactor types. This testing involves a high neutron flux environment and real-time imaging technology with advanced instrumentation with appropriate accuracy and resolution to study the fuel slumping behavior. With the aid of transient testing and adequate imaging tools, it is possible to test the safety basis for reactor and fuel designs that serves as a gateway in licensing advanced reactors in the future. To that end, it is crucial to fully understand advanced imaging techniques both analytically and via simulations. This paper presents an innovative method of supporting real-time imaging of fuel pins and other structures during transient testing. The major fuel-motion detection device that is studied in this dissertation is the Hodoscope which requires collimators. This paper provides 1) an MCNP model and simulation of a Transient Reactor Test (TREAT) core with a central fuel element replaced by a slotted fuel element that provides an open path between test samples and a hodoscope detector and 2) a choice of good filter to improve image resolution.

Keywords: hodoscope, transient testing, collimators, MCNP, TREAT, hodogram, filters

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Authors: T. Radu, R. Sreenivas, H. Albuflasa, A. Mustafa Khan, W. Aloqab

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The Kingdom of Bahrain, a small island country in the Gulf region, is experiencing fast economic growth resulting in a sharp increase in population and greater than ever amounts of waste being produced. However, waste management in the country is still very basic, with landfilling being the most popular option. Recycling is still a scarce practice, with small recycling businesses and initiatives emerging in recent years. This scenario is typical for other countries in the region, with similar amounts of per capita waste being produced. In this paper, we are reviewing current waste management practices in Bahrain by collecting data published by the Government and various authors, and by visiting the country’s only landfill site, Askar. In addition, we have performed a survey of the residents to learn more about the awareness and attitudes towards sustainable waste management strategies. A review of the available data on waste management indicates that the Askar landfill site is nearing its capacity. The site uses open tipping as the method of disposal. The highest percentage of disposed waste comes from the building sector (38.4%), followed by domestic (27.5%) and commercial waste (17.9%). Disposal monitoring and recording are often based on estimates of weight and without proper characterization/classification of received waste. Besides, there is a need for assessment of the environmental impact of the site with systematic monitoring of pollutants in the area and their potential spreading to the surrounding land, groundwater, and air. The results of the survey indicate low awareness of what happens with the collected waste in the country. However, the respondents have shown support for future waste reduction and recycling initiatives. This implies that the education of local communities would be very beneficial for such governmental initiatives, securing greater participation. Raising awareness of issues surrounding recycling and waste management and systematic effort to divert waste from landfills are the first steps towards securing sustainable waste management in the Kingdom of Bahrain.

Keywords: landfill, municipal solid waste, survey, waste management

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Authors: Amir Sattari, Mac Panah, Naeim Rashidfarokhi

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To enhance the mixing of fluid in a rectangular enclosure with a circular inlet and outlet, an energy-efficient approach is further investigated through computational fluid dynamics (CFD). Particle image velocimetry (PIV) measurements help confirm that the pulsation of the inflow velocity improves the mixing performance inside the enclosure considerably without increasing energy consumption. In this study, multiple CFD simulations with different turbulent models were performed. The results obtained were compared with experimental PIV results. This study investigates small-scale representations of flow patterns in a ventilated rectangular room. The objective is to validate the concept of an energy-efficient ventilation strategy with improved thermal comfort and reduction of stagnant air inside the room. Experimental and simulated results confirm that through pulsation of the inflow velocity, strong secondary vortices are generated downstream of the entrance wall-jet. The pulsatile inflow profile promotes a periodic generation of vortices with stronger eddies despite a relatively low inlet velocity, which leads to a larger boundary layer with increased kinetic energy in the occupied zone. A real-scale study was not conducted; however, it can be concluded that a constant velocity inflow profile can be replaced with a lower pulsated flow rate profile while preserving the mixing efficiency. Among the turbulent CFD models demonstrated in this study, SST-kω is most advantageous, exhibiting a similar global airflow pattern as in the experiments. The detailed near-wall velocity profile is utilized to identify the wall-jet instabilities that consist of mixing and boundary layers. The SAS method was later applied to predict the turbulent parameters in the center of the domain. In both cases, the predictions are in good agreement with the measured results.

Keywords: CFD, PIV, pulsatile inflow, ventilation, wall-jet

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Authors: Tharaki Hetti Arachchi

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Sri Lanka has undergone numerous changes in the fields of social-economic and cultural processors during the past decades. Consequently, the Sri Lankan construction industry was subjected to rapid growth while contributing a considerable amount to the national economy. The prevailing situation under the Covid-19 pandemic exhibited challenges to almost all of the sectors of the country in attaining success. Although productivity is one of the dimensions that measure the degree of project success, achieving sufficient productivity has become challengeable due to the Covid-19 outbreak. As employee motivation is an influential factor in defining productivity, the present study becomes significant in discovering ways of enhancing construction productivity via employee motivation. The study has adopted a combination of qualitative and quantitative methodologies in attaining the study objectives. While the research population refers to construction professionals in Sri Lanka, the study sample is aimed at Quantity Surveyors in the bottom and middle managements of organizational hierarchies. The data collection was implemented via primary and secondary sources. The primary data collection was accomplished by undertaking semi-structured interviews and online questionnaire surveys while sampling the overall respondents based on the purposive sample method. The responses of the questionnaire survey were gathered in a form of a ‘Likert Scale’ to examine the degree of applicability on each respondent. Overall, 76.36% of primary data were recovered from the expected count while obtaining 60 responses from the questionnaire survey and 24 responses from interviews. Secondary data were obtained by reviewing sources such as research articles, journals, newspapers, books, etc. The findings suggest adopting and enhancing sixteen motivational factors in achieving greater productivity in the Sri Lankan construction sector.

Keywords: Covid 19 pandemic, motivation, quantity surveying, Sri Lanka

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Authors: D. Naranchimeg, G. Ulziisaikhan

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Student dropout problem has not been recently investigated within the Mongolian higher education. A student dropping out is a personal decision, but it may cause unemployment and other social problems including low quality of life because students who are not completed a degree cannot find better-paid jobs. The research aims to determine percentage of at-risk students, and understand reasons for dropouts and to find a way to predict. The study based on the students of the Mongolian National University of Education including its Arkhangai branch school, National University of Mongolia, Mongolian University of Life Sciences, Mongolian University of Science and Technology, Mongolian National University of Medical Science, Ikh Zasag International University, and Dornod University. We conducted the paper survey by method of random sampling and have surveyed about 100 students per university. The margin of error - 4 %, confidence level -90%, and sample size was 846, but we excluded 56 students from this study. Causes for exclusion were missing data on the questionnaire. The survey has totally 17 questions, 4 of which was demographic questions. The survey shows that 1.4% of the students always thought to dropout whereas 61.8% of them thought sometimes. Also, results of the research suggest that students’ dropouts from university do not have relationships with their sex, marital and social status, and peer and faculty climate, whereas it slightly depends on their chosen specialization. Finally, the paper presents the reasons for dropping out provided by the students. The main two reasons for dropouts are personal reasons related with choosing wrong study program, not liking the course they had chosen (50.38%), and financial difficulties (42.66%). These findings reveal the importance of early prevention of dropout where possible, combined with increased attention to high school students in choosing right for them study program, and targeted financial support for those who are at risk.

Keywords: at risk students, dropout, faculty climate, Mongolian universities, peer climate

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Authors: Harsha Nagar, Vineet Aniya, Alka Kumari, Satyavathi B.

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In the present study, engineered bio-coal was produced from pressed seed cake, which otherwise is non-edible in origin. The production process involves a slow pyrolysis wherein, based on the optimization of process parameters; a substantial reduction in H/C and O/C of 77% was achieved with respect to the original ratio of 1.67 and 0.8, respectively. The bio-coal, so the product was found to have a higher heating value of 29899 kJ/kg with surface area 17 m²/g and pore volume of 0.002 cc/g. The functional characterization of bio-coal and its subsequent modification was carried out to enhance its active sites, which were further used as an adsorbent material for removal of 2,4,6-Trichlorophenol (2,4,6-TCP) herbicide from the aqueous stream. The point of zero charge for the bio-coal was found to be pH < 3 where its surface is positively charged and attracts anions resulting in the maximum 2, 4, 6-TCP adsorption at pH 2.0. The parametric optimization of the adsorption process was studied based on the Box-Behken design with the desirability approach. The results showed optimum values of adsorption efficiency of 74.04% and uptake capacity of 118.336 mg/g for an initial metal concentration of 250 mg/l and particle size of 0.12 mm at pH 2.0 and 1 g/L of bio-coal loading. Negative Gibbs free energy change values indicated the feasibility of 2,4,6-TCP adsorption on biochar. Decreasing the ΔG values with the rise in temperature indicated high favourability at low temperatures. The equilibrium modeling results showed that both isotherms (Langmuir and Freundlich) accurately predicted the equilibrium data, which may be attributed to the different affinity of the functional groups of bio-coal for 2,4,6-TCP removal. The possible mechanism for 2,4,6-TCP adsorption is found to be physisorption (pore diffusion, p*_p electron donor-acceptor interaction, H-bonding, and van der Waals dispersion forces) and chemisorption (phenolic and amine groups chemical bonding) based on the kinetics data modeling.

Keywords: engineered biocoal, 2, 4, 6-trichlorophenol, box behnken design, biosorption

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Authors: Manmeet Kaur, Madhu Vij

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The Board of Directors in a firm performs the primary role of an internal control mechanism. This Study seeks to understand the relationship between internal governance and performance of banks in India. The research paper investigates the effect of board structure (proportion of nonexecutive directors, gender diversity, board size and meetings per year) on the firm performance. This paper evaluates the impact of corporate governance mechanisms on bank’s financial performance using panel data for 28 listed banks in National Stock Exchange of India for the period of 2008-2014. Returns on Asset, Return on Equity, Tobin’s Q and Net Interest Margin were used as the financial performance indicators. To estimate the relationship among governance and bank performance initially the Study uses Pooled Ordinary Least Square (OLS) Estimation and Generalized Least Square (GLS) Estimation. Then a well-developed panel Generalized Method of Moments (GMM) Estimator is developed to investigate the dynamic nature of performance and governance relationship. The Study empirically confirms that two-step system GMM approach controls the problem of unobserved heterogeneity and endogeneity as compared to the OLS and GLS approach. The result suggests that banks with small board, boards with female members, and boards that meet more frequently tend to be more efficient and subsequently have a positive impact on performance of banks. The study offers insights to policy makers interested in enhancing the quality of governance of banks in India. Also, the findings suggest that board structure plays a vital role in the improvement of corporate governance mechanism for financial institutions. There is a need to have efficient boards in banks to improve the overall health of the financial institutions and the economic development of the country.

Keywords: board of directors, corporate governance, GMM estimation, Indian banking

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Authors: M. Mischopoulou, P. Naidis, S. Kalamaras, T. Kotsopoulos, P. Samaras

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The treatment of high strength wastewater by an Upflow Anaerobic Sludge Blanket (UASB) reactor has several benefits, such as high organic removal efficiency, short hydraulic retention time along with low operating costs. In addition, high volumes of biogas are released in these reactors, which can be utilized in several industrial facilities for energy production. This study aims at the examination of the application potential of anaerobic treatment of wastewater, with high molasses content derived from yeast manufacturing, by a lab-scale UASB reactor. The molasses wastewater and the sludge used in the experiments were collected from the wastewater treatment plant of a baker’s yeast manufacturing company. The experimental set-up consisted of a 15 L thermostated UASB reactor at 37 ◦C. Before the reactor start-up, the reactor was filled with sludge and molasses wastewater at a ratio 1:1 v/v. Influent was fed to the reactor at a flowrate of 12 L/d, corresponding to a hydraulic residence time of about 30 h. Effluents were collected from the system outlet and were analyzed for the determination of the following parameters: COD, pH, total solids, volatile solids, ammonium, phosphates and total nitrogen according to the standard methods of analysis. In addition, volatile fatty acid (VFA) composition of the effluent was determined by a gas chromatograph equipped with a flame ionization detector (FID), as an indicator to evaluate the process efficiency. The volume of biogas generated in the reactor was daily measured by the water displacement method, while gas composition was analyzed by a gas chromatograph equipped with a thermal conductivity detector (TCD). The effluent quality was greatly enhanced due to the use of the UASB reactor and high rate of biogas production was observed. The anaerobic treatment of the molasses wastewater by the UASB reactor improved the biodegradation potential of the influent, resulting at high methane yields and an effluent with better quality than the raw wastewater.

Keywords: anaerobic digestion, biogas production, molasses wastewater, UASB reactor

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Authors: Alicia Greenbank, Efrat Bengio

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The aim of this research was to examine the efficacy of the first course in Israel, whose objective is to train student teachers in the special education department to work cooperatively with parents of children with special needs. Studies often highlight the importance of cooperation between teachers and parents of students with special needs. Israel’s Special Education Law defines parents as complete partners, and the Ministry of Education encourages and even requires that partnership be present. Yet this partnership is difficult to achieve many kindergarten teachers, and teachers have a lot of difficulties establishing and managing a pattern of cooperation with their students’ parents. Often we see different perspectives on the child's development and needs, distrust, lack of appreciation, and communication difficulties on both sides – parents & teachers. The course describes a method of instilling the need for cooperation at an early stage of teacher training-in the teacher training program. 22 students in the special education program for early childhood education in the fourth year of learning took part in the course. The fourth-year is the experiential training year and the first time that students have worked in a school. The course consisted of 14 sessions. Seven parents of students with different disabilities participated at 6 of the sessions. The changes in the students' attitudes towards partnership and their ability to manage this partnership were carried out by examining the reports written by the students before the meetings with the parents and the reflections they wrote after each meeting with the parents and at the end of the course. Three themes emerged from the narrative analysis, corresponding to the three preconditions for joint activities with parents — Approach, Attitude, Appropriate Atmosphere, according to the Four A’s Model. The findings showed that a course combining meetings with parents of children with special needs offers many benefits for teacher training. The course raised student awareness of the question partnership, changed students’ approaches and attitudes towards the parents, stressed the importance of partnership, and provided students with tools for working with parents through the school. Based on the findings of this study, courses in this format can be applied in order to cooperate between teachers and parents, for example, parents of gifted children with special needs.

Keywords: Partnership with parents in special education, parents of children with disabilities, parents of children with special needs, parents’ involvement in special education

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Authors: Sebastiana Viphindratin, Silvi Asna

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The under ground economy phenomenon is exist in Indonesia. There are some factors which affect the existence this underground economy activity. One of them is a hierarchy power structure that handles the underground economy existence. The example of the existence of underground economy is the occurring informal market in Indonesia. Malang city is one of the city which has this kind of market. Junk night market (JNM) as an underground economy activity is arising in that city. The JNM is located in Gatot Subroto Sidewalk Street. The JNM is a illegal market which sell thrift, antique, imitation and black market goods. The JNM is interesting topic to be discussed, because this market is running in long time without any policy from local government. The JNM activity has their own “power” that run the market rules. Thus, it is important to analyze how the existence and power structure of JNM actors community are in Malang city. This research using qualitative method with phenomenological approach where we try to understand the phenomenon and related actors deeply. The aim of this research is to know the existence and power structure of JNM actors community in Malang. In JNM, there is no any entry barriers and tax charge from Malang government itself. Price competition also occurs because the buyer can do a bargain with the seller. In maintaining buyer loyalty, the JNM actors also do pre-order system. Even though, this market is an illegal market but the JNM actors also give the goods guarantee (without legal contract) as a formal market. In JNM actor’s community, there is no hierarchy and formal power structure. The role in JNM is managed by informal leaders who come up from the trading activity problems that are sidewalk and parking area dividing. Therefore, can be concluded that even the JNM is illegal market but it can survive with natural market pattern. In JNM development, JNM has positive and negative impact for Malang city. The positive impact of JNM is this market can open a new employment but the negative impact is there is no tax income from that market. Therefore, suggested that the government of Malang city should manage and give appropriate policies in this case.

Keywords: junk night market (JNM), Malang city, underground economy, illegal

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Authors: Neringa Bagdonaite

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Background: The main focus of this paper is to explore how self-determination interplays in suicidal and addictive context leading one to autonomously choose self-destructive addictive behaviour or suicidal intentions. Methods: Phenomenological descriptions of the experiential structure of self-determination in addiction and suicidal mental life are used. The phenomenological method describes structures of mental life from the first-person-perspective, with a focus on how an experienced object is given in a subject’s conscious experience. Results: A sense of self-determination in the context of suicidal and addictive behaviour is possibly impaired. In the context of suicide, it's proposed that suicide is always experienced at least minimally self-determined, as it's the last freely discovered self-efficient behaviour, in terms of radically changing one's desperate mental state. Suicide can never be experienced as fully self-determined because no future retrospective re-evaluation of behaviour is possible. Understanding self-determination in addiction is challenging because addicts perceive themselves and experience situations differently depending on: (I) their level of intoxication; (II) whether the situation is in the moment or in retrospect; and (III) the goals set out in that situation. Furthermore, within phenomenology addiction is described as an embodied custom, which‘s acquired and established while performing 'psychotropic technique'. The main goal of performing such a technique is to continue 'floating in an indifference state' or being 'comfortably numb'. Conclusions: Based on rich phenomenological descriptions of the studied phenomenon, this paper draws on the premise that to experience self-determination in both suicide and addiction, underlying desperate or negative emotional states are needed. Such underlying desperate or negative mental life experiences are required for one to pre-reflectively evaluate suicide or addictive behaviours as positive, relieving or effective in terms of changing one's emotional states. Such pre-reflective positive evaluations serve as the base for the continuation of behaviour and later are identified reflectively.

Keywords: addiction, phenomenology, self-determination, self-effectivity, suicide

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Authors: Hamidreza Khodaei, Behnaz Mahdavi, Leila Karshenas

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Nitric oxide (NO) is a small fast acting neurotransmitter, which is synthesized From L-arginine by nitric oxide synthase. Studies show that NO affects a wide range of reproductive functions. Steroidal hormones synthesis, LH surge during ovulation, follicular growth and ovulation are all affected by NO. Therefore, the objective of this study was to evaluate the relationship between NO and estradiol (E2) production in ovarian follicles and cysts in bovines. Two experiment groups were formed and serum and follicular fluid levels Of NO and estradiol (E2) was measured. In the first group, follicular fluids were obtained from 30 slaughtered cows. Follicles were divided into three groups according to follicular diameter: Small follicles, <5 mm, medium-sized follicles, 5 to 10 mm, and large follicles, >10 mm. 30 follicles were randomly selected within each group. Blood samples were obtained via jugular vein. NO concentrations in blood and ovarian follicular fluids were measured by Griess reaction method and radio-immunoassay respectively. In the second group: 12 cows in follicular phase and with cystic follicles were selected and a cystic follicle was obtained from each. NO and E2 levels were measured as done for the first experiment group. The data were analyzed by SAS software using ANOVA and Duncan’s test. NO concentrations of follicular fluids from large follicles were significantly higher than those of the medium and small-sized ones. There were significant differences in the concentrations of nitrite and nitrate (Stable metabolites of NO) between large and cystic follicles, with extremely low NO and high E2 levels in cystic follicles (p<0.01).The results suggest that paracrine effects of NO may play an important role in the control of ovarian follicle growth and development of cystic follicles in bovines. It seems that NO dictates its effects through inhibition of ovarian steroidal synthesis.

Keywords: nitric oxide, estradiol, cystic follicle, cow, oogenesis, oocyte maturation, follicular fluid

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Authors: Nida Iftikhar, Jamaluddin Thaheem, Bilal Iftikhar

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In the construction industry, adequate and effective decision-making can mean the difference between success and failure. Bidding is the most important element of the construction business since it is a mean by which contractors obtain work. This is probably the only option for any contractor firm to sustain in the market and achieve its objective of earning the profits by winning tenders. The capability to select most appropriate ventures not only defines the success and wellbeing of contractor firms but also their survival and sustainability in the industry. The construction practitioners are usually on their own when it comes to deciding on bidding for a project or not. Usually, experience-based solutions are offered where a lot of subjectivity is involved. This research has been opted considering the local construction industry of Pakistan in order to examine the critical success factors from contractors’ perspective while making bidding decisions, listing and evaluating critical factors in order of their importance, categorization of these factors into decision support & decision oppose groups and to develop a framework to help contractors in the decision-making process. Literature review, questionnaires, and structured interviews are used for identification and quantification of factors affecting bid/no bid decision-making. Statistical methods of ranking analysis and analytical hierarchy process of multi-criteria decision-making method are used for analysis. It is found that profitability, need for work and financial health of client are the most decisive factors in bid/no bid decision-making while project size, project type, fulfilling the tender conditions imposed by the client and relationship, identity & reputation of the client are least impact factors in bid/no bid decision-making. Further, to verify the developed framework, case studies have been conducted to evaluate the bid/no bid decision-making in building procurement. This is the first of its nature study in the context of the local construction industry and recommends using a holistic decision-making framework for such business-critical deliberations.

Keywords: bidding, bid decision-making, construction procurement, contractor

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Authors: Peifang Hsieh

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The prevention of child abuse has aroused serious concerns in Taiwan because of the disparity between the increasing amount of reported child abuse cases that doubled over the past decade and the scarcity of social workers. New Taipei city, with the most population in Taiwan and over 70% of its 4 million citizens are migrant families in which the needs of children can be easily neglected due to insufficient support from relatives and communities, sees urgency for a social support system, by preemptively identifying and outreaching high-risk families of child abuse, so as to offer timely assistance and preventive measure to safeguard the welfare of the children. Big data analysis is the inspiration. As it was clear that high-risk families of child abuse have certain characteristics in common, New Taipei city decides to consolidate detailed background information data from departments of social affairs, education, labor, and health (for example considering status of parents’ employment, health, and if they are imprisoned, fugitives or under substance abuse), to cross-reference for accurate and prompt identification of the high-risk families in need. 'The Service Center for High-Risk Families' (SCHF) was established to integrate data cross-departmentally. By utilizing the machine learning 'random forest method' to build a risk prediction model which can early detect families that may very likely to have child abuse occurrence, the SCHF marks high-risk families red, yellow, or green to indicate the urgency for intervention, so as to those families concerned can be provided timely services. The accuracy and recall rates of the above model were 80% and 65%. This prediction model can not only improve the child abuse prevention process by helping social workers differentiate the risk level of newly reported cases, which may further reduce their major workload significantly but also can be referenced for future policy-making.

Keywords: child abuse, high-risk families, big data analysis, risk prediction model

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Authors: Ramiz Kuliev, Fuad Kuliev-Smirnov

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The 'Shadow Sparring' training exercise is widely used in the training of boxers and martial artists. The main disadvantage of the usual shadow sparring is that the trainer cannot fully control such training and evaluate its results. During the competition, the athlete, preparing for the upcoming fight, imagines the Shadow (upcoming opponent) in accordance with his own imagination. A ‘Smart-Shadow Sparring’ (SSS) is an innovative version of the ‘Shadow Sparring’. During SSS, the fighter will see the Shadow (virtual opponent that moves, defends, and punches) and understand when he misses the punches from the Shadow. The task of a real athlete is to spar with a virtual one, move around, punch in the direction of unprotected areas of the Shadow and dodge his punches. Moves and punches of Shadow are set up before each training. The system will give the coach full information about virtual sparring: (i) how many and what type of punches has the fighter landed, (ii) accuracy of these punches, (iii) how many and what type of virtual punches (punches of Smart-Shadow) has the fighter missed, etc. SSS will be recorded as animated fighting of two fighters and will help the coach to analyze past training. SSS can be configured to fit the physical and technical characteristics of the next real opponent (size, techniques, speed, missed and landed punches, etc.). This will allow to simulate and rehearse the upcoming fight and improve readiness for the next opponent. For amateur fighters, SSS will be reconfigured several times during a tournament, when the real opponent becomes known. SSS can be used in three versions: (1) Digital Shadow: the athlete will see a Shadow on a monitor (2) VR-Shadow: the athlete will see a Shadow in a VR-glasses (3) Smart Shadow: a Shadow will be controlled by artificial intelligence. These technologies are based on the ‘semi-real simulation’ method. The technology allows coaches to train athletes remotely. Simulation of different opponents will help the athletes better prepare for competition. Repeat rehearsals of the upcoming fight will help improve results. SSS can improve results in Boxing, Taekwondo, Karate, and Fencing. 41 sets of medals will be awarded in these sports at the 2020 Olympic Games.

Keywords: boxing, combat sports, fight simulation, shadow sparring

Procedia PDF Downloads 136

Authors: Elucir Gir, Laelson Rochelle Milanês Sousa, Renata Karina Reis, Soraia Assad Nasbine Rabeh, Mayra Gonçalves Menegueti, Ana Cristina de Oliveira e Silva, Sheila Araújo Teles

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Context and significance: Nursing team professionals faced challenges in combating the COVID-19 pandemic around the world. They were subjected to exhausting workloads and prolonged use of Personal Protective Equipment. Using N95 masks for long periods of time can cause skin changes. In this context, health professionals who worked on the front lines of fighting the pandemic were more exposed to possible physical and psychological changes. Objective: The aim of the study was to analyze the factors associated with skin lesions resulting from the use of N95 masks among nursing team professionals. Method: The study was carried out in all regions of Brazil from October to December 2020, with professionals from the nursing team who worked in health care during the COVID-19 pandemic. Participants were recruited via social media, and information was collected electronically and stored on the Survey Monkey platform. Descriptive statistics were used to characterize the sample, association tests (Chi-square), with a statistical significance level of p < 0.05. Factors associated with skin lesions resulting from the use of an N95 mask were determined by Binary Logistic Regression, with a significance level of 5% (α = 0.05). Results: 8,405 nursing professionals participated in the study, 5,492 nurses (65.3%), 2,747 nursing technicians (32.7%), and 7,084 females (84.3%). Female nursing team professionals were 1.4 times more likely to develop skin lesions due to the use of N95 masks when compared to males (OR 1.4 [CI95% 1.22 – 1.59] p < 0.001). The following protective factors were identified: nursing technician (ORA 0.608 [CI95% 0.43 – 0.86] p = 0.005) and not having provided assistance in field hospitals for COVID-19 (0.73 [CI95% 0.65-0.81] p<0.000). Conclusion: It was concluded that female nursing team professionals were more likely to have skin changes related to the use of N95 masks. The need for intervention studies is emphasized in order to explore measures to prevent these types of injuries. Descritores: Nursing professionals; COVID-19; SARS-CoV-2; Brazil.

Keywords: nursing professionals, COVID-19, SARS-CoV-2, Brazil

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Authors: C. K. Ngaw

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Crystal facet engineering, which involves tuning and controlling a crystal surface and morphology, is a commonly employed strategy to optimize the performance of crystalline nanocrystals. The principle behind this strategy is that surface atomic rearrangement and coordination, which inherently determines their catalytic activity, can be easily tuned by morphological control. Because of this, the catalytic properties of a nanocrystal are closely related to the surface of an exposed facet, and it has provided great motivation for researchers to synthesize photocatalysts with high catalytic activity by maximizing reactive facets exposed through morphological control. In this contribution, octahedral NaInS₂ crystals have been successfully developed via solvothermal method. The formation of the octahedral NaInS₂ crystals was investigated using field emission scanning electron microscope (FESEM) and X-Ray diffraction (XRD), and results have shown that the concentration of sulphur precursor plays an important role in the growth process, leading to the formation of other NaInS₂ crystal structures in the form of hexagonal nanosheets and microspheres. Structural modeling analysis suggests that the octahedral NaInS₂ crystals were enclosed with {012} and {001} facets, while the nanosheets and microspheres are bounded with {001} facets only and without any specific facets, respectively. Visible-light photocatalytic H₂ evolution results revealed that the octahedral NaInS₂ crystals (~67 μmol/g/hr) exhibit ~6.1 and ~2.3 times enhancement as compared to the conventional NaInS₂ microspheres (~11 μmol/g/hr) and nanosheets (~29 μmol/g/hr), respectively. The H₂ enhancement of the NaInS₂ octahedral crystal is attributed to the presence of {012} facets on the surface. Detailed analysis of the octahedron model revealed obvious differences in the atomic arrangement between the {001} and {012} facets and this can affect the interaction between the water molecules and the surface facets before reducing into H₂ gas. These results highlight the importance of tailoring crystal morphology with highly reactive facets in improving photocatalytic properties.

Keywords: H₂ evolution, photocatalysis, octahedral, reactive facets

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