Search results for: integrated audit quality model

Authors: Yousef M. Alammari, Mahmoud A. Gaddoury, Reem A. Almohaini, Sara A. Alharbi, Lena S. Alsaleem, Lujain H. Allowaihiq, Maha H. Alrashid, Abdullah H. Alghamdi, Abdullah A. Alaryni

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Objective: The goal of this study was to establish the prevalence of neuropsychiatric symptoms in systemic lupus erythematosus (NPSLE) patients in Saudi Arabia and the variables that are linked to it. Methods: During June 2021, this cross-sectional study was carried out among SLE patients in Saudi Arabia. The Saudi Rheumatism Association exploited social media platforms to provide a self-administered online questionnaire to SLE patients. All data analyses were performed using the Statistical Packages for Social Sciences (SPSS) version 26. Results: Two hundred and five SLE patients participated in the study (females 91.3 % vs. males 8.7 %). In addition, 13.5 % of patients had a family history of SLE, and 26% had SLE for one to three years. Alteration or loss of sensation (53.4%), Fear (52.4%), and headache (48.1%) were the most prevalent signs of neuropsychiatric symptoms in systemic lupus erythematosus (NPSLE) patients. The prevalence of patients with NPSLE was 40%. In a multivariate regression model, fear, altered sensations, cerebrovascular illness, sleep disruption, and diminished interest in routine activities were identified as independent risk variables for NPSLE. Conclusion: Nearly half of SLE patients demonstrated NP manifestations, with significant symptoms including fear, alteration of sensation, cerebrovascular disease, sleep disturbance, and reduced interest in normal activities. To detect the pathophysiology of NPSLE, it is necessary to understand the relationship between neuropsychiatric morbidity and other relevant rheumatic disorders in the SLE population.

Keywords: neuropsychiatric, systemic lupus erythematosus, NPSLE, prevalence, SLE patients

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Authors: Bastian Waduge Naveen Harindu Hemasiri, Jae-Kwan Kim, Ji-Myon Lee

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Indium tin oxide (ITO) remains the industrial standard transparent conducting oxides with better performances. Recently, graphene becomes as a strong material with unique properties to replace the ITO. However, graphene/ITO hybrid composite material is a newly born field in the electronic world. In this study, the graphene/ITO composite bi-film was synthesized by a two steps process. 10 wt.% tin-doped, ITO thin films were produced by an environmentally friendly aqueous sol-gel spin coating technique with economical salts of In(NO3)3.H2O and SnCl4 without using organic additives. The wettability and surface free energy (97.6986 mJ/m2) enhanced oxygen plasma treated glass substrates were used to form voids free continuous ITO film. The spin-coated samples were annealed at 600 0C for 1 hour under low vacuum conditions to obtained crystallized, ITO film. The crystal structure and crystalline phases of ITO thin films were analyzed by X-ray diffraction (XRD) technique. The Scherrer equation was used to determine the crystallite size. Detailed information about chemical composition and elemental composition of the ITO film were determined by X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDX) coupled with FE-SEM respectively. Graphene synthesis was done under chemical vapor deposition (CVD) method by using Cu foil at 1000 0C for 1 min. The quality of the synthesized graphene was characterized by Raman spectroscopy (532nm excitation laser beam) and data was collected at room temperature and normal atmosphere. The surface and cross-sectional observation were done by using FE-SEM. The optical transmission and sheet resistance were measured by UV-Vis spectroscopy and four point probe head at room temperature respectively. Electrical properties were also measured by using V-I characteristics. XRD patterns reveal that the films contain the In2O3 phase only and exhibit the polycrystalline nature of the cubic structure with the main peak of (222) plane. The peak positions of In3d5/2 (444.28 eV) and Sn3d5/2 (486.7 eV) in XPS results indicated that indium and tin are in the oxide form only. The UV-visible transmittance shows 91.35 % at 550 nm with 5.88 x 10-3 Ωcm specific resistance. The G and 2D band in Raman spectroscopy of graphene appear at 1582.52 cm-1 and 2690.54 cm-1 respectively when the synthesized CVD graphene on SiO2/Si. The determined intensity ratios of 2D to G (I2D/IG) and D to G (ID/IG) were 1.531 and 0.108 respectively. However, the above-mentioned G and 2D peaks appear at 1573.57 cm-1 and 2668.14 cm-1 respectively when the CVD graphene on the ITO coated glass, the positions of G and 2D peaks were red shifted by 8.948 cm-1 and 22.396 cm-1 respectively. This graphene/ITO bi-film shows modified electrical properties when compares with sol-gel derived ITO film. The reduction of sheet resistance in the bi-film was 12.03 % from the ITO film. Further, the fabricated graphene/ITO bi-film shows 88.66 % transmittance at 550 nm wavelength.

Keywords: chemical vapor deposition, graphene, ITO, Raman Spectroscopy, sol-gel

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Authors: Yang Zhao, Feng Zhang, Xuanchu Duan

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Trans-differentiation of human Tenon fibroblasts (HTFs) to myo-fibroblasts and fibrosis of episcleral tissue are the most common reasons for the failure of glaucoma filtration surgery, with limited treatment options like antimetabolites which always have side-effects such as leakage of filter bulb, infection, hypotony, and endophthalmitis. Rosiglitazone, a specific thiazolidinedione is a synthetic high-affinity ligand for PPAR-r, which has been used in the treatment of type2 diabetes, and found to have pleiotropic functions against inflammatory response, cell proliferation and tissue fibrosis and to benefit to a variety of diseases in animal myocardium models, steatohepatitis models, etc. Here, in vitro we cultured primary HTFs and stimulated with TGF- β to induced myofibrogenic, then treated cells with Rosiglitazone to assess for fibrogenic response. In vivo, we used rabbit glaucoma model to establish the formation of post- trabeculectomy scarring. Then we administered subconjunctival injection with Rosiglitazone beside the filtering bleb, later protein, mRNA and immunofluorescence of fibrogenic markers are checked, and filtering bleb condition was measured. In vitro, we found Rosiglitazone could suppressed proliferation and migration of fibroblasts through macroautophagy via TGF- β /Smad signaling pathway. In vivo, on postoperative day 28, the mean number of fibroblasts in Rosiglitazone injection group was significantly the lowest and had the least collagen content and connective tissue growth factor. Rosiglitazone effectively controlled human and rabbit fibroblasts in vivo and in vitro. Its subconjunctiiva application may represent an effective, new avenue for the prevention of scarring after glaucoma surgery.

Keywords: fibrosis, glaucoma, macroautophagy, rosiglitazone

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Authors: Chakraborty Sudipta, A. R. Kambekar, Sarma Arnab

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Sea-level rise being one of the most important impacts of anthropogenic induced climate change resulting from global warming and melting of icebergs at Arctic and Antarctic, the investigations done by various researchers both on Indian Coast and elsewhere during the last decade has been reviewed in this paper. The paper aims to ascertain the propensity of consistency of different suggested methods to predict the near-accurate future sea level rise along the coast of Mumbai. Case studies at East Coast, Southern Tip and West and South West coast of India have been reviewed. Coastal Vulnerability Index of several important international places has been compared, which matched with Intergovernmental Panel on Climate Change forecasts. The application of Geographic Information System mapping, use of remote sensing technology, both Multi Spectral Scanner and Thematic Mapping data from Landsat classified through Iterative Self-Organizing Data Analysis Technique for arriving at high, moderate and low Coastal Vulnerability Index at various important coastal cities have been observed. Instead of data driven, hindcast based forecast for Significant Wave Height, additional impact of sea level rise has been suggested. Efficacy and limitations of numerical methods vis-à-vis Artificial Neural Network has been assessed, importance of Root Mean Square error on numerical results is mentioned. Comparing between various computerized methods on forecast results obtained from MIKE 21 has been opined to be more reliable than Delft 3D model.

Keywords: climate change, Coastal Vulnerability Index, global warming, sea level rise

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Authors: T. Hopkin, S. Lu, P. Rogers, M. Sexton

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Housing Associations (HAs) contribute circa 20% of the UK’s housing supply. HAs are however under increasing pressure as a result of funding cuts and rent reductions. Due to the increased pressure, a number of processes are currently being reviewed by HAs, especially how they manage and learn from defects. Learning from defects is considered a useful approach to achieving defect reduction within the UK housebuilding industry. This paper contributes to our understanding of how HAs learn from defects by undertaking an initial round table discussion with key HA stakeholders as part of an ongoing collaborative research project with the National House Building Council (NHBC) to better understand how house builders and HAs learn from defects to reduce their prevalence. The initial discussion shows that defect information runs through a number of groups, both internal and external of a HA during both the defects management process and organizational learning (OL) process. Furthermore, HAs are reliant on capturing and recording defect data as the foundation for the OL process. During the OL process defect data analysis is the primary enabler to recognizing a need for a change to organizational routines. When a need for change has been recognized, new options are typically pursued to design out defects via updates to a HAs Employer’s Requirements. Proposed solutions are selected by a review board and committed to organizational routine. After implementing a change, both structured and unstructured feedback is sought to establish the change’s success. The findings from the HA discussion demonstrates that OL can achieve defect reduction within the house building sector in the UK. The paper concludes by outlining a potential ‘learning from defects model’ for the housebuilding industry as well as describing future work.

Keywords: defects, new homes, housing association, organizational learning

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Authors: Nadeem Akhtar, An Ran, Cornelius B. Pratt

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China’s President Xi' vision of Belt and Road Initiative, an infrastructural project of development and connectivity, is attracting international students to Chinese universities, with Pakistan and India among the top-10 countries of origin of those students (Ministry of Education China, 2018). An additional factor in international students’ interest in Chinese universities is their improving global rankings of Chinese universities. Against that backdrop, this study addresses two overarching questions: (a) What factors explain South Asian students’ study-away experiences, particularly in their multicultural environments? and (b) What role do new media play in their adaptation to that environment? This study is guided by Stephen’s (2011) theoretical model, which suggests that social networks influence immigrants’ interactions with host and home culture. The present study used a structured questionnaire distributed through both WeChat and other online platforms to international students studying in Chinese universities. Preliminary results are threefold: (a) that the frequency of use of social media is a predictor of the level of adjustment of the students to their multicultural environment; (b) that social engagement with their international-student peers is a moderating factor in their experiential outcomes; and (c) length of stay in Chinese universities, surprisingly, was not a predictor of adaptation. A major implication of these findings is that, even though social media tend to be criticized for contributing to anomie and to diminishing social capital among youths and millennials, they can be poignant tools for cultural adaptation, particularly among international students in China. It remains to be seen if such outcomes occur among international students in other countries or world regions.

Keywords: adaptation, China's Belt and Road Initiative, international students, social media

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Authors: Ferhat Erdal, Osman Tunca, Serkan Tas, Serdar Carbas

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Web-expanded steel beams provide an easy and economical solution for the systems having longer structural members. The main goal of manufacturing these beams is to increase the moment of inertia and section modulus, which results in greater strength and rigidity. Until recently, there were two common types of open web-expanded beams: with hexagonal openings, also called castellated beams, and beams with circular openings referred to as cellular beams, until the generation of sinusoidal web-expanded beams. In the present research, the optimum design of a new generation beams, namely sinusoidal web-expanded beams, will be carried out and the design results will be compared with castellated and cellular beam solutions. Thanks to a reduced fabrication process and substantial material savings, the web-expanded beam with sinusoidal holes (Angelina™ Beam) meets the economic requirements of steel design problems while ensuring optimum safety. The objective of this research is to carry out non-linear finite element analysis (FEA) of the web-expanded beam with sinusoidal holes. The FE method has been used to predict their entire response to increasing values of external loading until they lose their load carrying capacity. FE model of each specimen that is utilized in the experimental studies is carried out. These models are used to simulate the experimental work to verify of test results and to investigate the non-linear behavior of failure modes such as web-post buckling, shear buckling and vierendeel bending of beams.

Keywords: steel structures, web-expanded beams, angelina beam, optimum design, failure modes, finite element analysis

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Authors: Abid Kousay

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Appeared and developed essentially in large companies and multinationals, Talent Management (TM) in Small and Medium-Sized Enterprises (SMEs) has remained an under-explored subject till today. Although the literature on TM in the Anglo-Saxon context is developing, it remains monopolized in non-European contexts, especially in France. Therefore, this article aims to address these shortcomings through contributing to TM issues by adopting a multilevel approach holding the goal of reaching a global holistic vision of interactions between various levels while applying TM. A qualitative research study carried out within 12 SMEs in France, built on the methodological perspective of grounded theory, will be used in order to go beyond description, to generate or discover a theory or even a unified theoretical explanation. Our theoretical contributions are the results of the grounded theory, the fruit of context considerations and the dynamic of the multilevel approach. We aim firstly to determine the perception of talent and TM in SMEs. Secondly, we formalize TM in SME through the empowerment of all 3 levels in the organization (individual, collective, and organizational). And we generate a multilevel dynamic system model, highlighting the institutionalization dimension in SMEs and the managerial conviction characterized by the domination of the leader’s role. Thirdly, this first study sheds light on the importance of rigorous implementation of TM in SMEs in France by directing CEO and HR and TM managers to focus on elements that upstream TM implementation and influence the system internally. Indeed, our systematic multilevel approach policy reminds them of the importance of strategic alignment while translating TM policy into strategies and practices in SMEs.

Keywords: French context, multilevel approach, talent management, , TM system

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Authors: Lisa Rudolfsson

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Socio-cognitive factors, such as social support and attribution of blame, influence the victim’s psychological adjustment after the abuse. Furthermore, the response from the person that the victim first confides to effect adjustment following the abuse. In Sweden, although police are investigating most of the reported cases of rape, very few rape-cases leads to trial and sentence. For many women who have been raped, contact with the police officer when reporting the crime will, therefore, be the most notable experience of how representatives for the Swedish society regard and handle what has happened. Hence, it seems urgent to gather information about these initial meetings. This study is part of a three-year research project, titled 'Female rape victims: Quality of initial police and medical care contact', funded by the Swedish Crime Victim and Support Authority. The focus of this study was on police officers in Sweden: their thoughts and experiences of meeting with raped women. Forthcoming are interviews with raped women about their experiences of meeting with police. Sixteen police officers participated in three focus groups and one interview. The participants consisted of five men and eleven women. Focus groups and interview were audio recorded and transcribed verbatim. The material was analyzed using thematic analysis. Participants described how violence against women was not a priority in Swedish society or within the Police Authority. They talked about rape cases as a Sisyphean work-task that put high demands on them, while they also lacked training and support. They expressed a wish to offer the woman some kind of restoration, and they talked about their work as potentially making a difference for the woman – even if she did not get juridical justice. However, participants also described that they did not feel validated in their hard work. They talked about working rape cases as causing them a great deal of frustration - directed towards the Police Authority, the juridical system, colleagues, and sometimes towards the woman. Participants also described how meeting with raped women was a work that affected them in a personal manner. Listening to stories about sexual violence made the participants sad, and they described it as a struggle to understand. They described wondering how the woman’s life turned out and how they sometimes questioned if they had done enough. Some of the conclusions concern the lack of prerequisites needed for police officers to be able to offer a good-enough treatment of raped women, as well as the lack of tools needed for police officers to care for themselves. In lack of training, validation, and support, the knowledge of how to offer a good- enough treatment of raped women becomes a task learned by doing. Attempts to offer, if not legal justice, then at least some kind of restoration becomes a personal task, dependent on individual police officers. It seems urgent that we address the risk of police officers’ frustration building up to be detrimental for both the crime victim and the officer her/himself.

Keywords: focus groups, police, raped women, restoration

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Authors: Arup Pramanik

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Most of the cities in the developing countries like Siliguri Municipal Corporation Area (SMCA) and Raiganj Municipality (RM) in West Bengal, India are changing typically in terms of demographic, economic and social relationship due to rapid pace of urbanization. The mushrooming growth of slums in SMCA and RM is the direct consequence of urbanization and migration due to regional imbalance, unbalanced growth process which is posing a serious threat to sustainable development of the country. Almost all the slums happen to be a breeding ground for poverty, negligence, and disease. Unpredictable growth of slums and poverty alleviation has now become a serious challenge to the global and national policy makers for the development of the slum dwellers. The ethical dimension of the poor in the cities like SMCA and RM stands on equal opportunities, inclusive and harmonious living without discrimination of any kind. But, the migrant slum dwellers in SMCA and RM do not possess high skill or education to enable them to find well paid employment in the formal sector and the surplus urban labour force is compelled to generate its own means of employment and survival in the informal sector. The survey data of the households has been analysedin terms of percentage, descriptive statistics which includes mean, Standard Deviation (SD), ANOVA (Mean Difference) etc., to analyse the socio economic variables of the households. The study shows that the migrant labour forces living in the slums are derived from the social security measures in both the municipal areas of SMCA and RM. The urban poor in the cities of SMCA and RM rely heavily on social capital amongst all the capital assets to help them ‘get by’ and ‘get ahead’. Despite, the slum dwellers in the study areas are vulnerable with respect to other determinants of capital assets. It is noteworthy that Indian plans of anti-poverty programmes was in a proper place even after the neo-liberal regime, where the basic idea behind the massive shift of various welfare and service oriented strategy to poverty reduction strategy for the benefit of the urban poor with the trickle down effects. But, the overall impact of the trickledown effect was unsatisfactory. The objective of the Paper is to assess the magnitude of migration and absorption in the urban labour market. Issues relating to capital formation, social security measures and the support of the Welfare State in order to meet 'Sustainable Development Goals'. This study also highlights the quality of life of urban poor migrants in terms of capital formation and livelihoods.

Keywords: migration, slums, labour market, capital formation, social security

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Authors: Bibha Kumari, Nigel P. Brunton, Dilip K. Rai, Brijesh K. Tiwari

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Edible mushrooms possess numerous functional components like homo- and hetero- β-glucans [β(1→3), β(1→4) and β(1→6) glucosidic linkages], chitins, ergosterols, bioactive polysaccharides and peptides imparting health beneficial properties to mushrooms. Some of the proven biological activities of mushroom extracts are antioxidant, antimicrobial, immunomodulatory, cholesterol lowering activity by inhibiting a key cholesterol metabolism enzyme i.e. 3-hydroxy-3-methyl-glutaryl CoA reductase (HMGCR), angiotensin I-converting enzyme (ACE) inhibition. Application of novel extraction technologies like pulsed electric field (PEF) and high power ultrasound offers clean, green, faster and efficient extraction alternatives with enhanced and good quality extracts. Sequential PEF followed by ultrasound assisted extraction (UAE) were applied to recover bioactive enriched fractions from industrial white button mushroom (Agaricus bisporus) stalk waste using environmentally friendly and GRAS solvents i.e. water and water/ethanol combinations. The PEF treatment was carried out at 60% output voltage, 2 Hz frequency for 500 pulses of 20 microseconds pulse width, using KCl salt solution of 0.6 mS/cm conductivity by the placing 35g of chopped fresh mushroom stalks and 25g of salt solution in the 4x4x4cm3 treatment chamber. Sequential UAE was carried out on the PEF pre-treated samples using ultrasonic-water-bath (USB) of three frequencies (25 KHz, 35 KHz and 45 KHz) for various treatment times (15-120 min) at 80°C. Individual treatment using either PEF or UAE were also investigation to compare the effect of each treatment along with the combined effect on the recovery and bioactivity of the crude extracts. The freeze dried mushroom stalk powder was characterised for proximate compositional parameters (dry weight basis) showing 64.11% total carbohydrate, 19.12% total protein, 7.21% total fat, 31.2% total dietary fiber, 7.9% chitin (as glucosamine equivalent) and 1.02% β-glucan content. The total phenolic contents (TPC) were determined by the Folin-Ciocalteu procedure and expressed as gallic-acid-equivalents (GAE). The antioxidant properties were ascertained using DPPH and FRAP assays and expressed as trolox-equivalents (TE). HMGCR activity and molecular mass of β-glucans will be measured using the commercial HMG-CoA Reductase Assay kit (Sigma-Aldrich) and size exclusion chromatography (HPLC-SEC), respectively. Effects of PEF, UAE and their combination on the antioxidant capacity, HMGCR inhibition and β-glucans content will be presented.

Keywords: β-glucan, mushroom stalks, pulsed electric field (PEF), ultrasound assisted extraction (UAE)

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Authors: Ren Moses, Emmanuel Kidando, Eren Ozguven, Yassir Abdelrazig

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Although older drivers (defined as those of age 65 and above) are less involved with speeding, alcohol use as well as night driving, they are more vulnerable to severe crashes. The major contributing factors for severe crashes include frailty and medical complications. Several studies have evaluated the contributing factors on severity of crashes. However, few studies have established the impact of travel time reliability (TTR) on road safety. In particular, the impact of TTR on senior adults who face several challenges including hearing difficulties, decreasing of the processing skills and cognitive problems in driving is not well established. Therefore, this study focuses on determining possible impacts of TTR on the traffic safety with focus on elderly drivers. Historical travel speed data from freeway links in the study area were used to calculate travel time and the associated TTR metrics that is, planning time index, the buffer index, the standard deviation of the travel time and the probability of congestion. Four-year information on crashes occurring on these freeway links was acquired. The binary logit model estimated using the Markov Chain Monte Carlo (MCMC) sampling technique was used to evaluate variables that could be influencing elderly crash severity. Preliminary results of the analysis suggest that TTR is statistically significant in affecting the severity of a crash involving an elderly driver. The result suggests that one unit increase in the probability of congestion reduces the likelihood of the elderly severe crash by nearly 22%. These findings will enhance the understanding of TTR and its impact on the elderly crash severity.

Keywords: highway safety, travel time reliability, elderly drivers, traffic modeling

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Authors: Bidzina Matsaberidze

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It is known that, in emergency situations, multi-attribute group decision-making (MAGDM) models are characterized by insufficient objective data and a lack of time to respond to the task. Evidence theory is an effective tool for describing such incomplete information in decision-making models when the expert and his knowledge are involved in the estimations of the MAGDM parameters. We consider an emergency decision-making model, where expert assessments on humanitarian aid from distribution centers (HADC) are represented in q-rung ortho-pair fuzzy numbers, and the data structure is described within the data body theory. Based on focal probability construction and experts’ evaluations, an objective function-distribution centers’ selection ranking index is constructed. Our approach for solving the constructed bicriteria partitioning problem consists of two phases. In the first phase, based on the covering’s matrix, we generate a matrix, the columns of which allow us to find all possible partitionings of the HADCs with the service centers. Some constraints are also taken into consideration while generating the matrix. In the second phase, based on the matrix and using our exact algorithm, we find the partitionings -allocations of the HADCs to the centers- which correspond to the Pareto-optimal solutions. For an illustration of the obtained results, a numerical example is given for the facility location-selection problem.

Keywords: emergency MAGDM, q-rung orthopair fuzzy sets, evidence theory, HADC, facility location problem, multi-objective combinatorial optimization problem, Pareto-optimal solutions

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Authors: Saima Kalsoom, Sobia Masood, Muhammad Faran

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This study aimed to examine the association between emotional intelligence and gender role attitudes of married individuals. Another aim of this study was to test the moderating role of gender work status of married individuals for predicting gender role attitudes from emotional intelligence. A sample of (N = 500) married working men and women (both working & housewives) was approached through purposive convenience sampling technique. The data was collected employing cross-sectional research design. The indigenous versions of the Gender Role Attitudes Scale and perceived Emotional Intelligence Scale were used. The results of alpha coefficients for both the scales and subscales used in this study designated satisfactory evidence for internal consistency and reliability. Assessment of correlation coefficients showed significant positive correlation between gender role attitudes and emotional intelligence, subfactors of emotional intelligence i.e., emotional self-regulation, emotional self-awareness, and interpersonal skills with gender role attitudes. Results of model testing revealed that gender (the effect was significant for women) and work status (the effect was more significant for married working women than married working men and housewives) of the married individuals significantly moderated the relationship between emotional intelligence and gender role attitudes into the positive direction. Further, it was also found that gender and work status also moderated the relationship between emotional self-regulation (as sub factor of emotional intelligence) and gender role attitudes in a positive direction. In conclusion, this empirical evidence is vital contribution derived from the traditional and collectivistic socio-cultural background of Pakistan.

Keywords: gender role attitudes, emotional intelligence, emotional self-regulation, gender, work status, married working women

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Authors: Abdisalam Hassan Muse, Samuel Mwalili, Oscar Ngesa

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A generalized log-logistic distribution with variable shapes of the hazard rate was introduced and studied, extending the log-logistic distribution by adding an extra parameter to the classical distribution, leading to greater flexibility in analysing and modeling various data types. The proposed distribution has a large number of well-known lifetime special sub-models such as; Weibull, log-logistic, exponential, and Burr XII distributions. Its basic mathematical and statistical properties were derived. The method of maximum likelihood was adopted for estimating the unknown parameters of the proposed distribution, and a Monte Carlo simulation study is carried out to assess the behavior of the estimators. The importance of this distribution is that its tendency to model both monotone (increasing and decreasing) and non-monotone (unimodal and bathtub shape) or reversed “bathtub” shape hazard rate functions which are quite common in survival and reliability data analysis. Furthermore, the flexibility and usefulness of the proposed distribution are illustrated in a real-life data set and compared to its sub-models; Weibull, log-logistic, and BurrXII distributions and other parametric survival distributions with 3-parmaeters; like the exponentiated Weibull distribution, the 3-parameter lognormal distribution, the 3- parameter gamma distribution, the 3-parameter Weibull distribution, and the 3-parameter log-logistic (also known as shifted log-logistic) distribution. The proposed distribution provided a better fit than all of the competitive distributions based on the goodness-of-fit tests, the log-likelihood, and information criterion values. Finally, Bayesian analysis and performance of Gibbs sampling for the data set are also carried out.

Keywords: hazard rate function, log-logistic distribution, maximum likelihood estimation, generalized log-logistic distribution, survival data, Monte Carlo simulation

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Authors: Guermache Ahmed Chafik, Khelfellah Ismail, Ait-Ali Takfarines

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The Savonius vertical axis wind turbine is characterized by sufficient starting torque at low wind speeds, simple design and does not require orientation to the wind direction; however, the developed power is lower than other types of wind turbines such as Darrieus. To increase these performances several studies and researches have been developed, such as optimizing blades shape, using passive controls and also minimizing power losses sources like the resisting torque due to friction. This work aims to estimate the performance of a Savonius wind turbine introducing a User Defined Function to the CFD model analyzing resisting torque. This User Defined Function is developed to simulate the action of the wind speed on the rotor; it receives the moment coefficient as an input to compute the rotational velocity that should be imposed on computational domain rotating regions. The rotational velocity depends on the aerodynamic moment applied on the turbine and the resisting torque, which is considered a linear function. Linking the implemented User Defined Function with the CFD solver allows simulating the real functioning of the Savonius turbine exposed to wind. It is noticed that the wind turbine takes a while to reach the stationary regime where the rotational velocity becomes invariable; at that moment, the tip speed ratio, the moment and power coefficients are computed. To validate this approach, the power coefficient versus tip speed ratio curve is compared with the experimental one. The obtained results are in agreement with the available experimental results.

Keywords: resistant torque modeling, Savonius wind turbine, user-defined function, vertical axis wind turbine performances

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Authors: Eyüp S. Akbas, Betul Ayaz, Beyza S. Haksever, Sema Basat

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We aimed to evaluate the relationship between insulin resistance, muscle mass and muscle strength in patients with Hepatitis B virus-related cirrhosis. In our study, there were 65 patients with hepatitis B virus-related cirrhosis in Child A and B group and 65 healthy control individual. Control group was chosen between patients who admitted to the internal medicine clinic and had no pathological values in a routine examination. Muscle mass index was calculated with bioimpedance analysis for both groups to determine muscle strength and muscle mass. Handgrip strength, arm, and calf circumference were measured. In both groups, HOMA-IR was calculated to determine insulin resistance. Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) value was detected 3,47±3,80 in the study group and 1,83±1,20 in control group. There were significant differences between the two groups in arm circumference, fasting insulin, fasting glucose, HOMA-IR, High-density lipoprotein (HDL) and total cholesterol parameters. The correlation coefficient between muscle mass and insulin resistance was statistically insignificant, especially in the study group. In healthy individuals group and all the groups, there wasn’t a correlation between muscle mass and insulin resistance. The upper limit for HOMA-IR was determined as 3,2. In control group, %78,9 of individuals were in HOMA-IR ( < 3.2) group and %21,1 of them were in ( ≥ 3,2) group. In study group, %68,3 of individuals were in HOMA-IR ( < 3,2) group and %31.7 were in HOMA-IR ( ≥ 3,2) group. In our study, we did not find a relationship between muscle mass and insulin resistance in patients with liver cirrhosis. In the study group, we detected a positive relationship between muscle mass, handgrip strength, and calf circumference. We did not find a relationship between insulin resistance and handgrip strength in our study.

Keywords: cirrhosis, hepatitis B, Insulin resistance, muscle mass

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Authors: Chih-Yi Ho, Tzu-Fang Chang, Chih-Chia Huang, Chia-Yen Lee

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In dental clinics, the dentists use the periapical radiography image to assess the effectiveness of endodontic treatment of teeth with chronic apical periodontitis. Periapical radiography images are taken at different times to assess alveolar bone variation before and after the root canal treatment, and furthermore to judge whether the treatment was successful. Current clinical assessment of apical tissue recovery relies only on dentist personal experience. It is difficult to have the same standard and objective interpretations due to the dentist or radiologist personal background and knowledge. If periapical radiography images at the different time could be registered well, the endodontic treatment could be evaluated. In the image registration area, it is necessary to assign representative control points to the transformation model for good performances of registration results. However, detection of representative control points (feature points) on periapical radiography images is generally very difficult. Regardless of which traditional detection methods are practiced, sufficient feature points may not be detected due to the low-contrast characteristics of the x-ray image. Barnard detector is an algorithm for feature point detection based on grayscale value gradients, which can obtain sufficient feature points in the case of gray-scale contrast is not obvious. However, the Barnard detector would detect too many feature points, and they would be too clustered. This study uses the local extrema of clustering feature points and the suppression radius to overcome the problem, and compared different feature point detection methods. In the preliminary result, the feature points could be detected as representative control points by the proposed method.

Keywords: feature detection, Barnard detector, registration, periapical radiography image, endodontic treatment

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Authors: Jaballah Jamil

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KLD (Peter Kinder, Steve Lydenberg and Amy Domini) research & analytics is an independent intermediary of social performance information that adopts an investor-pay model. KLD rating agency does not have an explicit monitoring on the rated firm which suggests that KLD ratings may not include private informations. Moreover, the incapacity of KLD to predict accurately the extra-financial rating of Enron casts doubt on the reliability of KLD ratings. Therefore, we first investigate whether KLD ratings affect investors' perception by studying the effect of KLD rating changes on firms' financial performances. Second, we study the impact of the Enron scandal on investors' perception of KLD rating changes by comparing the effect of KLD rating changes on firms' financial performances before and after the failure of Enron. We propose an empirical study that relates a number of equally-weighted portfolios returns, excess stock returns and book-to-market ratio to different dimensions of KLD social responsibility ratings. We first find that over the last two decades KLD rating changes influence significantly and negatively stock returns and book-to-market ratio of rated firms. This finding suggests that a raise in corporate social responsibility rating lowers the firm's risk. Second, to assess the Enron scandal's effect on the perception of KLD ratings, we compare the effect of KLD rating changes before and after the Enron scandal. We find that after the Enron scandal this significant effect disappears. This finding supports the view that the Enron scandal annihilates the KLD's effect on Socially Responsible Investors. Therefore, our findings may question results of recent studies that use KLD ratings as a proxy for Corporate Social Responsibility behavior.

Keywords: KLD social rating agency, investors' perception, investment decision, financial performance

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Authors: Andrea Trevino Gavito, Diego Klabjan, Sanjiv Shah

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Echocardiograms serve as pivotal resources for clinicians in diagnosing cardiac conditions, offering non-invasive insights into a heart’s structure and function. When echocardiographic studies are conducted, no standardized labeling of the acquired views is performed. Employing machine learning algorithms for automated echocardiogram view detection has emerged as a promising solution to enhance efficiency in echocardiogram use for diagnosis. However, existing approaches predominantly rely on supervised learning, necessitating labor-intensive expert labeling. In this paper, we introduce a fully unsupervised echocardiographic view detection framework that leverages convolutional autoencoders to obtain lower dimensional representations and the K-means algorithm for clustering them into view-related groups. Our approach focuses on discriminative patches from echocardiographic frames. Additionally, we propose a trainable inverse average layer to optimize the decoding of average operations. By integrating both public and proprietary datasets, we obtain a marked improvement in model performance when compared to utilizing a proprietary dataset alone. Our experiments show boosts of 15.5% in accuracy and 9.0% in the F-1 score for frame-based clustering, 25.9% in accuracy, and 19.8% in the F-1 score for view-based clustering. Our research highlights the potential of unsupervised learning methodologies and the utilization of open-sourced data in addressing the complexities of echocardiogram interpretation, paving the way for more accurate and efficient cardiac diagnoses.

Keywords: artificial intelligence, machine learning, unsupervised learning, self-supervised representation learning, echocardiography, echocardiographic view detection

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Authors: Agah Tuğrul Korucu, Handan Atun

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Diversity and usefulness of information that used in education are have increased due to development of technology. Web technologies have made enormous contributions to the distance learning system especially. Mobile systems, one of the most widely used technology in distance education, made much easier to access web technologies. Not bounding by space and time, individuals have had the opportunity to access the information on web. In addition to this, the storage of educational information and resources and accessing these information and resources is crucial for both students and teachers. Because of this importance, development and dissemination of web technologies supply ease of access to information and resources are provided by web technologies. Dynamic web technologies introduced as new technologies that enable sharing and reuse of information, resource or applications via the Internet and bring websites into expandable platforms are commonly known as Web 2.0 technologies. Cloud systems are one of the dynamic web technologies that defined as a model provides approaching the demanded information independent from time and space in appropriate circumstances and developed by NIST. One of the most important advantages of cloud systems is meeting the requirements of users directly on the web regardless of hardware, software, and dealing with install. Hence, this study aims at using cloud services in education and investigating the services provided by the cloud computing. Survey method has been used as research method. In the findings of this research the fact that cloud systems are used such studies as resource sharing, collaborative work, assignment submission and feedback, developing project in the field of education, and also, it is revealed that cloud systems have plenty of significant advantages in terms of facilitating teaching activities and the interaction between teacher, student and environment.

Keywords: cloud systems, cloud systems in education, online learning environment, integration of information technologies, e-learning, distance learning

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Authors: Vilma Zydziunaite, Gitana Balezentiene, Vilma Zydziunaite

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Teaching is one of most responsible profession, and it is not only a job of an artisan. This profes-sion needs a developed ability to identify oneself with the chosen teaching profession. Research questions: How teachers characterize their authentic individual professional identity? What factors teachers exclude, which support and limit the professional identity? Aim was to develop the grounded theory (GT) about teacher’s professional identity (TPI). Research methodology is based on Charmaz GT version. Data were collected via semi-structured interviews with the he sample of 12 teachers. Findings. 15 extracted categories revealed that the core of TPI is teacher’s professional calling. Premises of TPI are family support, motives for choos-ing teacher’s profession, teacher’s didactic competence. Context of TPI consists of teacher compli-ance with the profession, purposeful preparation for pedagogical studies, professional growth. The strategy of TPI is based on teacher relationship with school community strengthening. The profes-sional frustration limits the TPI. TPI outcome includes teacher recognition, authority; professional mastership, professionalism, professional satisfaction. Dimensions of TPI GT the past (reaching teacher’s profession), present (teacher’s commitment to professional activity) and future (teacher’s profession reconsideration). Conclusions. The substantive GT describes professional identity as complex, changing and life-long process, which develops together with teacher’s personal identity and is connected to professional activity. The professional decision "to be a teacher" is determined by the interaction of internal (professional vocation, personal characteristics, values, self-image, talents, abilities) and external (family, friends, school community, labor market, working condi-tions) factors. The dimensions of the TPI development includes: the past (the pursuit of the teaching profession), the present (the teacher's commitment to professional activity) and the future (the revi-sion of the teaching profession). A significant connection emerged - as the teacher's professional commitment strengthens (creating a self-image, growing the teacher's professional experience, recognition, professionalism, mastery, satisfaction with pedagogical activity), the dimension of re-thinking the teacher's profession weakens. This proves that professional identity occupies an im-portant place in a teacher's life and it affects his professional success and job satisfaction. Teachers singled out the main factors supporting a teacher's professional identity: their own self-image per-ception, professional vocation, positive personal qualities, internal motivation, teacher recognition, confidence in choosing a teaching profession, job satisfaction, professional knowledge, professional growth, good relations with the school community, pleasant experiences, quality education process, excellent student achievements.

Keywords: grounded theory, teacher professional identity, semi-structured interview, school, students, school community, family

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Authors: Musa Miah

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Society and social activities are directly governed by political sociology. Political sociology has an impact on the whole of human society, the interrelationships of people in society, social responsibilities and duties, the nature of society, society and culture of different countries, conducting social activities, social change and social development. Through this, the correct knowledge and decision are made by analyzing the complexities of society in different ways. In modern civilized society, people need to get accurate knowledge about how they live, their behavior, customs and principles. The need for political sociology is undeniable, even if new plans are to be adopted for the development of society. The importance of practicing political sociology is immense if any country, nation, or society is to move forward on the path of sustainable development. Research has shown that political sociology is an essential aspect of the social impact of development, sociological analysis of poverty or underdevelopment, development of human values in individual life. The importance of political sociology for knowing the overall aspect of society is undeniable. Because, to know about social problems, to identify social problems, to find the cause of any social problem, one needs to know political sociology. Apart from knowing about the class structure of the society, people of different classes and professions live in the society. It is possible to gain knowledge about. He is also involved in various societies, communities and groups in the country and abroad. Therefore, research has shown that in order to successfully solve any task of the society, it is necessary to know the society in full. Media Studies: Media studies are directly related to socialization. Media strategy has had a positive impact on the management and direction of society. At present, Media Studies in Bangladesh is working towards providing opportunities for up-to-date and quality higher education. Introduced Department of Journalism, Communication and Media Studies in different universities of Bangladesh. The department has gained immense popularity since its inception. Here the top degree holders, as well as eminent editors, senior journalists, writers and researchers, are giving their opinions. Now there is ample scope for research in newspapers, magazines, radio, television and online media as well as outside of work as an advertising-documentary filmmaker or in domestic and foreign NGOs or other corporate organizations. According to the study, media studies have had a positive impact on the media in Bangladesh, especially television channels, the expansion and development of online media and the creation of clear ideas about communication, journalism and the media. Workshops, seminars and discussions are being held on contemporary national and international issues in addition to theoretical concepts. Journalism, communication and mass media are quite exceptional and challenging compared to the traditional subjects considering the present times. In this regard, there is a unique opportunity to build a modern society with taste and personality without mere employment.

Keywords: Bangladesh, Dhaka, social activities, political sociology

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Authors: M. N. Baig, F. N. Khan, M. Junaid

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Titanium alloys are widely employed in aerospace, medical, chemical, and marine applications. These alloys offer many advantages such as low specific weight, high strength to weight ratio, excellent corrosion resistance, high melting point and good fatigue behavior. These attractive properties make titanium alloys very unique and therefore they require special attention in all areas of processing, especially welding. In this work, 1.6 mm thick sheets of Ti-5Al-2,5Sn, an alpha titanium (α-Ti) alloy, were welded using electron beam (EBW) and laser beam (LBW) welding processes to achieve a full penetration Bead-on Plate (BoP) configuration. The weldments were studied using polarized optical microscope, SEM, EDS and XRD. Microhardness distribution across the weld zone and smooth and notch tensile strengths of the weldments were also recorded. Residual stresses using Hole-drill Strain Measurement (HDSM) method and deformation patterns of the weldments were measured for the purpose of comparison of the two welding processes. Fusion zone widths of both EBW and LBW weldments were found to be approximately equivalent owing to fairly similar high power densities of both the processes. Relatively less oxide content and consequently high joint quality were achieved in EBW weldment as compared to LBW due to vacuum environment and absence of any shielding gas. However, an increase in heat-affected zone width and partial ά-martensitic transformation infusion zone of EBW weldment were observed because of lesser cooling rates associated with EBW as compared with LBW. The microstructure infusion zone of EBW weldment comprised both acicular α and ά martensite within the prior β grains whereas complete ά martensitic transformation was observed within the fusion zone of LBW weldment. Hardness of the fusion zone in EBW weldment was found to be lower than the fusion zone of LBW weldment due to the observed microstructural differences. Notch tensile specimen of LBW exhibited higher load capacity, ductility, and absorbed energy as compared with EBW specimen due to the presence of high strength ά martensitic phase. It was observed that the sheet deformation and deformation angle in EBW weldment were more than LBW weldment due to relatively more heat retention in EBW which led to more thermal strains and hence higher deformations and deformation angle. The lowest residual stresses were found in LBW weldments which were tensile in nature. This was owing to high power density and higher cooling rates associated with LBW process. EBW weldment exhibited highest compressive residual stresses due to which the service life of EBW weldment is expected to improve.

Keywords: Laser and electron beam welding, Microstructure and mechanical properties, Residual stress and distortions, Titanium alloys

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Authors: Montserrat Crespi Vallbona, Marta Domínguez Pérez

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Globalization impacts on cities and especially on their centers, especially on those spaces more visible and coveted. Changes are involved in processes such as touristification, gentrification or studentification, in addition of shop trendiness. The city becomes a good of interchange rather than a communal good for its inhabitants and consequently, its value is monetized. So, these different tendencies are analyzed: on one hand, the presence of tourists, the home rental increase, the explosion of businesses related to tourism; on the other hand; the return of middle classes or gentries to the center in a socio-spatial model that has changed highlighting the centers by their culture and their opportunities as well as by the value of public space and centrality; then, the interest of students (national and international) to be part of these city centers as dynamic groups and emerging classes with a higher purchasing power and better cultural capital than in the past; and finally, the conversion of old stores into modern ones, where vintage trend and the renewal of antiquity is the essence. All these transforming processes impact the European cities and redefine their image. All these trends reinforce the impression and brand of the urban center as an attractive space for investment, keeping such nonsense meaningful. These four tendencies have been spreading correlatively impacting the centers and transforming them involving the displacement of former residents of these spaces and revitalizing the center that is financed and commercialized in parallel. The cases of Madrid and Barcelona as spaces of greater evidence in Spain of these tendencies serve to illustrate these processes and represent the spearhead. Useful recommendations are presented to urban planners to find the conciliation of communal and commercialized spaces.

Keywords: gentrification, shop trendiness, studentification, touristification

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Authors: Zhou Shangcheng, Yi Sicen

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Objective: To understand the mortality patterns of Zhangwan District in 2010 and provide the basis for the development of scientific and rational health policy. Methods: Data are collected from the Sixth Census of Zhangwan District and disease surveillance system. The statistical analysis include death difference between age, gender, region and time and the related factors. Methods developed for the Global Burden of Disease (GBD) Study by the World Bank and World Health Organization (WHO) were adapted and applied to Zhangwan District population health data. DALY rate per 1,000 was calculated for varied causes of death. SPSS 16 is used by statistic analysis. Results: From the data of death population of Zhangwan District we know the crude mortality rate was 6.03 ‰. There are significant differences of mortality rate in male and female population which was respectively 7.37 ‰ and 4.68 ‰. 0 age group population life expectancy in Zhangwan District in 2010 was 78.40 years old(Male 75.93, Female 81.03). The five leading causes of YLL in descending order were: cardiovascular diseases(42.63DALY/1000), malignant neoplasm (23.73DALY/1000), unintentional injuries (5.84DALY/1000), Respiratory diseases(5.43 DALY/1000), Respiratory infections (2.44DALY/1000). In addition, there are strong relation between the marital status , educational level and mortality in some to a certain extend. Conclusion Zhangwan District, as city level, is at lower mortality levels. The mortality of the total population of Zhangwan District has a downward trend and life expectancy is rising.

Keywords: sixth census, Zhangwan district, death level differences, influencing factors, cause of death

Procedia PDF Downloads 257

Authors: Wisam H. Benamer, Ehab A. Elfallah, Mohamed A. Elshaari, Farag A. Elshaari

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A challenge for laboratories is to provide bacterial identification and antibiotic sensitivity results within a short time. Hence, advancement in the required technology is desirable to improve timing, accuracy and quality. Even with the current advances in methods used for both phenotypic and genotypic identification of bacteria the need is there to develop method(s) that enhance the outcome of bacteriology laboratories in accuracy and time. The hypothesis introduced here is based on the assumption that the chromosome of any bacteria contains unique sequences that can be used for its identification and typing. The outcome of a pilot study designed to test this hypothesis is reported in this manuscript. Methods: The complete chromosome sequences of several bacterial species were downloaded to use as search targets for unique sequences. Visual basic and SQL server (2014) were used to generate a complete set of 18-base long primers, a process started with reverse translation of randomly chosen 6 amino acids to limit the number of the generated primers. In addition, the software used to scan the downloaded chromosomes using the generated primers for similarities was designed, and the resulting hits were classified according to the number of similar chromosomal sequences, i.e., unique or otherwise. Results: All primers that had identical/similar sequences in the selected genome sequence(s) were classified according to the number of hits in the chromosomes search. Those that were identical to a single site on a single bacterial chromosome were referred to as unique. On the other hand, most generated primers sequences were identical to multiple sites on a single or multiple chromosomes. Following scanning, the generated primers were classified based on ability to differentiate between medically important bacterial and the initial results looks promising. Conclusion: A simple strategy that started by generating primers was introduced; the primers were used to screen bacterial genomes for match. Primer(s) that were uniquely identical to specific DNA sequence on a specific bacterial chromosome were selected. The identified unique sequence can be used in different molecular diagnostic techniques, possibly to identify bacteria. In addition, a single primer that can identify multiple sites in a single chromosome can be exploited for region or genome identification. Although genomes sequences draft of isolates of organism DNA enable high throughput primer design using alignment strategy, and this enhances diagnostic performance in comparison to traditional molecular assays. In this method the generated primers can be used to identify an organism before the draft sequence is completed. In addition, the generated primers can be used to build a bank for easy access of the primers that can be used to identify bacteria.

Keywords: bacteria chromosome, bacterial identification, sequence, primer generation

Procedia PDF Downloads 182

Authors: Cristina Diaz, Lucia Perez-Gandarillas, Gonzalo Garcia-Fuentes, Simone Visigalli, Roberto Canziani, Giuseppe Di Florio, Paolo Gronchi

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During their lifetime, industrial machines are often subjected to chemical, mechanical and thermal extreme conditions. In some cases, the loss of efficiency comes from the degradation of the surface as a result of its exposition to abrasive environments that can cause wear. This is a common problem to be solved in industries of diverse nature such as food, paper or concrete industries, among others. For this reason, a good selection of the material is of high importance. In the machine design context, stainless steels such as AISI 304 and 316 are widely used. However, the severity of the external conditions can require additional protection for the steel and sometimes coating solutions are demanded in order to extend the lifespan of these materials. Therefore, the development of effective coatings with high wear resistance is of utmost technological relevance. In this research, bilayer coatings made of Titanium-Tantalum, Titanium-Niobium, Titanium-Hafnium, and Titanium-Zirconium have been developed using magnetron sputtering configuration by PVD (Physical Vapor Deposition) technology. Their tribological behavior has been measured and evaluated under different environmental conditions. Two kinds of steels were used as substrates: AISI 304, AISI 316. For the comparison with these materials, titanium alloy substrate was also employed. Regarding the characterization, wear rate and friction coefficient were evaluated by a tribo-tester, using a pin-on-ball configuration with different lubricants such as tomato sauce, wine, olive oil, wet compost, a mix of sand and concrete with water and NaCl to approximate the results to real extreme conditions. In addition, topographical images of the wear tracks were obtained in order to get more insight of the wear behavior and scanning electron microscope (SEM) images were taken to evaluate the adhesion and quality of the coating. The characterization was completed with the measurement of nanoindentation hardness and elastic modulus. Concerning the results, thicknesses of the samples varied from 100 nm (Ti-Zr layer) to 1.4 µm (Ti-Hf layer) and SEM images confirmed that the addition of the Ti layer improved the adhesion of the coatings. Moreover, results have pointed out that these coatings have increased the wear resistance in comparison with the original substrates under environments of different severity. Furthermore, nanoindentation hardness results showed an improvement of the elastic strain to failure and a high modulus of elasticity (approximately 200 GPa). As a conclusion, Ti-Ta, Ti-Zr, Ti-Nb, and Ti-Hf are very promising and effective coatings in terms of tribological behavior, improving considerably the wear resistance and friction coefficient of typically used machine materials.

Keywords: coating, stainless steel, tribology, wear

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Authors: Milad Abbasi

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Carbon fiber-reinforced polymer (CFRP) composite structures are increasingly being utilized in the automotive industry due to their lightweight and specific energy absorption capabilities. Although it is impossible to predict composite mechanical properties directly using theoretical methods, various research has been conducted so far in the literature for accurate simulation of CFRP structures' energy-absorbing behavior. In this research, axial compression experiments were carried out on hand lay-up unidirectional CFRP composite tubes. The fabrication method allowed the authors to extract the material properties of the CFRPs using ASTM D3039, D3410, and D3518 standards. A neural network machine learning algorithm was then utilized to build a robust prediction model to forecast the axial compressive properties of CFRP tubes while reducing high-cost experimental efforts. The predicted results have been compared with the experimental outcomes in terms of load-carrying capacity and energy absorption capability. The results showed high accuracy and precision in the prediction of the energy-absorption capacity of the CFRP tubes. This research also demonstrates the effectiveness and challenges of machine learning techniques in the robust simulation of composites' energy-absorption behavior. Interestingly, the proposed method considerably condensed numerical and experimental efforts in the simulation and calibration of CFRP composite tubes subjected to compressive loading.

Keywords: CFRP composite tubes, energy absorption, crushing behavior, machine learning, neural network

Procedia PDF Downloads 140

Authors: Elizabeta Sivevska, Sunchica Petrovska, Vaska Antevska, Lidija Todorovska, Sanja Manchevska, Beti Dejanova, Ivanka Karagjozova, Jasmina Pluncevic Gligoroska

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Introduction: Body composition plays an important role in the selection of young soccer players and it is associated with their successful performance. The most commonly used model of body composition divides the body into two compartments: fat components and fat-free mass (muscular and bone components). The aims of the study were to determine the body composition parameters of young male soccer players and to show the differences in age groups. Material and methods: A sample of 52 young male soccer players, with an age span from 9 to 14 years were divided into two groups according to the age (group 1 aged 9 to 12 years and group 2 aged 12 to 14 years). Anthropometric measurements were taken according to the method of Mateigka. The following measurements were made: body weight, body height, circumferences (arm, forearm, thigh and calf), diameters (elbow, knee, wrist, ankle) and skinfold thickness (biceps, triceps, thigh, leg, chest, abdomen). The measurements were used in Mateigka’s equations. Results: Body mass components were analyzed as absolute values (in kilograms) and as percentage values: the muscular component (MC kg and MC%), the bone component (BCkg and BC%) and the body fat (BFkg and BF%). The group up to 12 years showed the following mean values of the analyzed parameters: MM=21.5kg; MM%=46.3%; BC=8.1kg; BC%=19.1%; BF= 6.3kg; BF%= 15.7%. The second group aged 12-14 year had mean values of body composition parameters as follows: MM=25.6 kg; MM%=48.2%; BC = 11.4 kg; BC%=21.6%; BF= 8.5 kg; BF%= 14. 7%. Conclusions: The young soccer players aged 12 up to 14 years who are in the pre-pubertal phase of growth and development had higher bone component (p<0.05) compared to younger players. There is no significant difference in muscular and fat body component between the two groups of young soccer players.

Keywords: body composition, young soccer players, body fat, fat-free mass

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