Search results for: S. Reaz Ahmed

Authors: Mohammad Noor Hisham Osman, Ahmed Razman Abdul Latiff, Zaidi Mat Daud, Zulkarnain Muhamad Sori

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The problem that Malaysian auditors do not issue going concern opinion (GC opinion) to seriously financially distressed companies is still a pressing issue. Policy makers, particularly the Financial Statement Review Committee (FSRC) of Malaysian Institute of Accountant, have raised this issue as early as in 2009. Similar problem happened in the US, UK, and many developing countries. It is important for auditors to issue GC opinion properly because such opinion is one signal about the viability of a company much needed by stakeholders. There are at least two unanswered questions or research gaps in the literature on determinants of GC opinion. Firstly, is client’s probability of failure associated with GC opinion issuance? Secondly, to what extent influential owners (management, family, and institution) moderate the association between client probability of failure and GC opinion issuance. The objective of this study is, therefore, twofold; (1) To examine the extent of the relationship between the probability of client failure and the issuance of GC opinion and (2) To examine the level of management, family, and institutional ownerships moderate the association between client probability of failure and the issuance of GC opinion. This study is quantitative in nature, and the sources of data are secondary (mainly company’s annual reports). A total of four hypotheses have been developed and tested on data accumulated from annual reports of seriously financially distressed Malaysian public listed companies. Data from 2006 to 2012 on a sample of 644 observations have been analyzed using panel logistic regression. It is found that certainty (rather than probability) of client failure affects the issuance of GC opinion. In addition, it is found that only the level of family ownership does positively moderate the relationship between client probability of failure and GC opinion issuance. This study is a contribution to auditing literature as its findings can enhance our understanding about audit quality; particularly on the variables that are associated with the issuance of GC opinion. The findings of this study shed light on the roles family owners in GC opinion issuance process, and this would open ways for the researcher to suggest measures that can be used to tackle the problem of auditors do not want to issue GC opinion to financially distressed clients. The measures to be suggested can be useful to policy makers in formulating future promulgations.

Keywords: audit quality, auditing, auditor characteristics, going concern opinion, Malaysia

Procedia PDF Downloads 239

Authors: Mohammed Elghazy, Ahmed El Refai, Usama Ebead, Antonio Nanni

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Rehabilitating corrosion-damaged reinforced concrete (RC) structures has been accomplished using various techniques such as steel plating, external post-tensioning, and external bonding of fiber reinforced polymer (FRP) composites. This paper reports on the use of an innovative technique to strengthen corrosion-damaged RC structures using fabric-reinforced cementitious matrix (FRCM) composites. FRCM consists of dry-fiber fabric embedded in cement-based matrix. Twelve large-scale RC beams were constructed and tested in flexural monotonic and fatigue loads. Prior to testing, ten specimens were subjected to accelerated corrosion process for 140 days leading to an average mass loss in the tensile steel bars of 18.8 %. Corrosion was restricted to the main reinforcement located in the middle third of the beam span. Eight corroded specimens were repaired and strengthened while two virgin and two corroded-unrepaired/unstrengthened beams were used as benchmarks for comparison purpose. The test parameters included the FRCM materials (Carbon-FRCM, PBO-FRCM), the number of FRCM plies, the strengthening scheme, and the type of loading (monotonic and fatigue). The effects of the pervious parameters on the flexural response, the mode of failure, and the fatigue life were reported. Test results showed that corrosion reduced the yield and ultimate strength of the beams. The corroded-unrepaired specimen failed to meet the provisions of the ACI-318 code for crack width criteria. The use of FRCM significantly increased the ultimate strength of the corroded specimen by 21% and 65% more than that of the corroded-unrepaired specimen. Corrosion significantly decreased the fatigue life of the corroded-unrepaired beam by 77% of that of the virgin beam. The fatigue life of the FRCM repaired-corroded beams increased to 1.5 to 3.8 times that of the corroded-unrepaired beam but was lower than that of the virgin specimen. The specimens repaired with U-wrapped PBO-FRCM strips showed higher fatigue life than those repaired with the end-anchored bottom strips having similar number of PBO-FRCM-layers. PBO-FRCM was more effective than Carbon-FRCM in restoring the fatigue life of the corroded specimens.

Keywords: corrosion, concrete, fabric-reinforced cementitious matrix (FRCM), fatigue, flexure, repair

Procedia PDF Downloads 282

Authors: M. Gulam Kibria, Shourav Ahmed, Kais Zaman

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In system analysis, the information on the uncertain input variables cause uncertainty in the system responses. Different probabilistic approaches for uncertainty representation and propagation in such cases exist in the literature. Different uncertainty representation approaches result in different outputs. Some of the approaches might result in a better estimation of system response than the other approaches. The NASA Langley Multidisciplinary Uncertainty Quantification Challenge (MUQC) has posed challenges about uncertainty quantification. Subproblem A, the uncertainty characterization subproblem, of the challenge posed is addressed in this study. In this subproblem, the challenge is to gather knowledge about unknown model inputs which have inherent aleatory and epistemic uncertainties in them with responses (output) of the given computational model. We use two different methodologies to approach the problem. In the first methodology we use sampling-based uncertainty propagation with first order error analysis. In the other approach we place emphasis on the use of Percentile-Based Optimization (PBO). The NASA Langley MUQC’s subproblem A is developed in such a way that both aleatory and epistemic uncertainties need to be managed. The challenge problem classifies each uncertain parameter as belonging to one the following three types: (i) An aleatory uncertainty modeled as a random variable. It has a fixed functional form and known coefficients. This uncertainty cannot be reduced. (ii) An epistemic uncertainty modeled as a fixed but poorly known physical quantity that lies within a given interval. This uncertainty is reducible. (iii) A parameter might be aleatory but sufficient data might not be available to adequately model it as a single random variable. For example, the parameters of a normal variable, e.g., the mean and standard deviation, might not be precisely known but could be assumed to lie within some intervals. It results in a distributional p-box having the physical parameter with an aleatory uncertainty, but the parameters prescribing its mathematical model are subjected to epistemic uncertainties. Each of the parameters of the random variable is an unknown element of a known interval. This uncertainty is reducible. From the study, it is observed that due to practical limitations or computational expense, the sampling is not exhaustive in sampling-based methodology. That is why the sampling-based methodology has high probability of underestimating the output bounds. Therefore, an optimization-based strategy to convert uncertainty described by interval data into a probabilistic framework is necessary. This is achieved in this study by using PBO.

Keywords: aleatory uncertainty, epistemic uncertainty, first order error analysis, uncertainty quantification, percentile-based optimization

Procedia PDF Downloads 219

Authors: Ahmed Auda, Manjree Agarwala, Giles Hardya, Yonglin Rena

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Botrytis cinerea is a major pest for many plants. It can attack a wide range of plant parts. It can attack buds, flowers, and leaves, stems, and fruit. However, B. cinerea can be mixed with other diseases that cause the same damage. There are many species of botrytis and more than one different strains of each. Botrytis might infect the foliage of nursery stock stored through winter in damp conditions. There are no known resistant plants. Botrytis must have nutrients or food source before it infests the plant. Nutrients leaking from wounded plant parts or dying tissue like old flower petals give the required nutrients. From this food, the fungus becomes more attackers and invades healthy tissue. Dark to light brown rot forms in the ill tissue. High humidity conditions support the growth of this fungus. However, we suppose that selection pressure can act on the morphological and neurophysiologic filter properties of the receiver and on both the biochemical and the physiological regulation of the signal. Communication is implied when signal and receiver evolves toward more and more specific matching, culminating. In other hand, receivers respond to portions of a body odor bouquet which is released to the environment not as an (intentional) signal but as an unavoidable consequence of metabolic activity or tissue damage. Each year Botrytis species can cause considerable economic losses to plant crops. Even with the application of strict quarantine and control measures, these fungi can still find their way into crops and cause the imposition of onerous restrictions on exports. Blueberry fruit mould caused by a fungal infection usually results in major losses during post-harvest storage. Therefore, the management of infection in early stages of disease development is necessary to minimize losses. The overall purpose of this study will develop sensitive, cheap, quick and robust diagnostic techniques for the detection of B. cinerea in blueberry. The specific aim was designed to investigate the performance of volatile organic compounds (VOCs) in the detection and discrimination of blueberry fruits infected by fungal pathogens with an emphasis on Botrytis in the early storage stage of post-harvest.

Keywords: botrytis cinerea, blueberry, GC/MS, VOCs

Procedia PDF Downloads 222

Authors: Rizwan Ahmed Bhutto, Noor ul ain Hira Bhutto, Mingwei Wang, Shahid Iqbal, Jiang Yi

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Curcumin, a natural polyphenolic compound, boasts numerous health benefits; however, its industrial applications are hindered by instabilities and poor solubility. Encapsulating curcumin in Pickering emulsion presents a promising strategy to enhance its bioavailability. Yet, the development of an efficient and straightforward method to fabricate a natural emulsifier for Pickering emulsion poses a significant challenge. Chitosan has garnered attention due to its non-toxicity and excellent emulsifying properties. This study aimed to prepare four distinct types of self-aggregated chitosan particles using a pH-responsive self-assembling approach. The properties of the aggregated particles were adjusted by pH, degree of deacetylation (DDA), and molecular weight (MW), thereby controlling surface charge, size (ranging from nano to micro and floc), and contact angle. Pickering emulsions were then formulated using these various aggregated particles. As MW and pH increased and DDA decreased, the networked structures of the aggregated particles formed, resulting in highly elastic gels that were more resistant to the breakdown of Pickering emulsion at ambient temperature. With elevated temperatures, the kinetic energy of the aggregated particles increased, disrupting hydrogen bonds and potentially transforming the systems from fluids to gels. The Pickering emulsion based on aggregated particles served as a carrier for curcumin encapsulation. It was observed that DDA and MW played crucial roles in regulating drug loading, encapsulation efficiency, and release profile. This research sheds light on selecting suitable chitosan for controlling the release of bioactive compounds in Pickering emulsions, considering factors such as adjustable rheological properties, microstructure, and macrostructure. Furthermore, this study introduces an environmentally friendly and cost-effective synthesis of pH-responsive aggregate particles without the need for high-pressure homogenizers. It underscores the potential of aggregate particles with various MWs and DDAs for encapsulating other bioactive compounds, offering valuable applications in industries including food, flavor/fragrance, cosmetics, and medicine.

Keywords: chitosan, molecular weight, rheological properties, curcumin encapsulation

Procedia PDF Downloads 45

Authors: Hanaa M. Abu El Einin, Ahmed T. Sharaf El- Din

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Biomphalaria snails play an integral role in the transmission of Schistosoma mansoni, the causative agent for human schistosomiasis. Two species of Biomphalaria were reported from Egypt, Biomphalaria alexandrina and Biomphalaria glabrata, and later on a hybrid of B. alexandrina and B. glabrata was reported in streams at Nile Delta. All were known to be excellent hosts of S. mansoni. Host-parasite relationship can be viewed in terms of snail susceptibility and parasite infectivity. The objective of this study will highlight the progress that has been made in using molecular approaches to describe the correct identification of snail species that participating in transmission of schistosomiasis, rapid diagnose of infection in addition to susceptibility and resistance type. Snails were identified using of molecular methods involving Randomly Amplified Polymorphic DNA (RAPD), Polymerase Chain Reaction, Restriction Fragment Length Polymorphisms (PCR-RFLP) and Species - specific- PCR. Molecular approaches to diagnose parasite in snails from Egypt: Nested PCR assay and small subunit (SSU) rRNA gene. Also RAPD PCR for study susceptible and resistance phenotype. The results showed that RAPD- PCR, PCR-RFLP and species-specific-PCR techniques were confirmed that: no evidence for the presence of B. glabrata in Egypt, All Biomphalaria snails collected identified as B. alexandrina snail i-e B alexandrinia is a common and no evidence for hybridization with B. glabrata. The adopted specific nested PCR assay revealed much higher sensitivity which enables the detection of S. mansoni infected snails down to 3 days post infection. Nested PCR method for detection of infected snails using S. mansoni fructose -1,6- bisphosphate aldolase (SMALDO) primer, these primers are specific only for S. mansoni and not cross reactive with other schistosomes or molluscan aldolases Nested PCR for such gene is sensitive enough to detect one cercariae. Genetic variations between B. alexandrina strains that are susceptible and resistant to Schistosoma infec¬tion using a RAPD-PCR showed that 39.8% of the examined snails collected from the field were resistant, while 60.2% of these snails showed high infection rates. In conclusion the genetics of the intermediate host plays a more important role in the epidemiological control of schistosomiasis.

Keywords: biomphalaria, molecular differentiation, parasite detection, schistosomiasis

Procedia PDF Downloads 182

Authors: Wasan Ismail Khalil, Hisham Khalid Ahmed, Zainab Ali

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Structural Lightweight Aggregate Concrete (SLWAC) has been developed in recent years because it reduces the dead load, cost, thermal conductivity and coefficient of thermal expansion of the structure. So SLWAC has the advantage of being a relatively green building material. Lightweight Aggregate (LWA) is either occurs as natural material such as pumice, scoria, etc. or as artificial material produced from different raw materials such as expanded shale, clay, slate, etc. The use of SLWAC in Iraq is limited due to the lack in natural LWA. The existence of Iraqi clay deposit with different types and characteristics leads to the idea of producing artificial expanded clay aggregate. The main aim in this work is to present of the properties of artificial LWA produced in the laboratory. Available local bentonite clay which occurs in the Western region of Iraq was used as raw material to produce the LWA. Sodium silicate as liquid industrial waste material from glass plant was mixed with bentonite clay in mix proportion 1:1 by weight. The manufacturing method of the lightweight aggregate including, preparation and mixing of clay and sodium silicate, burning of the mixture in the furnace at the temperature between 750-800˚C for two hours, and finally gradually cooling process. The produced LWA was then crushed to small pieces then screened on standard sieve series and prepared with grading which conforms to the specifications of LWA. The maximum aggregate size used in this investigation is 10 mm. The chemical composition and the physical properties of the produced LWA are investigated. The results indicate that the specific gravity of the produced LWA is 1.5 with the density of 543kg/m3 and water absorption of 20.7% which is in conformity with the international standard of LWA. Many trail mixes were carried out in order to produce LWAC containing the artificial LWA produced in this research. The selected mix proportion is 1:1.5:2 (cement: sand: aggregate) by weight with water to cement ratio of 0.45. The experimental results show that LWAC has oven dry density of 1720 kg/m3, water absorption of 8.5%, the thermal conductivity of 0.723 W/m.K and compressive strength of 23 N/mm2. The SLWAC produced in this research can be used in the construction of different thermal insulated buildings and masonry units. It can be concluded that the SLWA produced in this study contributes to sustainable development by, using industrial waste materials, conserving energy, enhancing the thermal and structural efficiency of concrete.

Keywords: expanded clay, lightweight aggregate, structural lightweight aggregate concrete, sustainable

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Authors: Ahmed Slami, Med El Amine Brixi Nigassa, Nassima Labdelli, Sofiane Soulimane, Arnaud Pothier

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Many people suffer from diabetes, a disease marked by abnormal levels of sugar in the blood; 285 million people have diabetes, 6.6% of the world adult population (in 2010), according to the International Diabetes Federation. Insulin medicament is invented to be injected into the body. Generally, the injection requires the patient to do it manually. However, in many cases he will be unable to inject the drug, saw that among the side effects of hyperglycemia is the weakness of the whole body. The researchers designed a medical device that injects insulin too autonomously by using micro-pumps. Many micro-pumps of concepts have been investigated during the last two decades for injecting molecules in blood or in the body. However, all these micro-pumps are intended for slow infusion of drug (injection of few microliters by minute). Now, the challenge is to develop micro-pumps for fast injections (1 microliter in 10 seconds) with accuracy of the order of microliter. Recently, studies have shown that only piezoelectric actuators can achieve this performance, knowing that few systems at the microscopic level were presented. These reasons lead us to design new smart microsystems injection drugs. Therefore, many technological advances are still to achieve the improvement of materials to their uses, while going through their characterization and modeling action mechanisms themselves. Moreover, it remains to study the integration of the piezoelectric micro-pump in the microfluidic platform features to explore and evaluate the performance of these new micro devices. In this work, we propose a new micro-pump model based on piezoelectric actuation with a new design. Here, we use a finite element model with Comsol software. Our device is composed of two pumping chambers, two diaphragms and two actuators (piezoelectric disks). The latter parts will apply a mechanical force on the membrane in a periodic manner. The membrane deformation allows the fluid pumping, the suction and discharge of the liquid. In this study, we present the modeling results as function as device geometry properties, films thickness, and materials properties. Here, we demonstrate that we can achieve fast injection. The results of these simulations will provide quantitative performance of our micro-pumps. Concern the spatial actuation, fluid rate and allows optimization of the fabrication process in terms of materials and integration steps.

Keywords: COMSOL software, piezoelectric, micro-pump, microfluidic

Procedia PDF Downloads 330

Authors: Ajved Ahmed

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This research paper explores the intricate relationship between sports activities and disability, aiming to shed light on the multifaceted impacts of sports participation on individuals with disabilities. As the world grapples with the challenges posed by the growing population of people with disabilities, understanding the role of sports in their lives becomes increasingly important. The paper begins by providing a comprehensive overview of the diverse forms of disabilities, emphasizing the wide spectrum of physical, sensory, and cognitive impairments. It then delves into the benefits of sports activities for individuals with disabilities, highlighting the profound physical, psychological, and social advantages that engagement in sports can offer. These benefits encompass improved physical fitness, enhanced self-esteem and mental well-being, increased social integration, and a sense of empowerment and independence. Furthermore, the paper examines the barriers and challenges that individuals with disabilities often encounter when attempting to participate in sports activities, ranging from inaccessible facilities to societal prejudices and stereotypes. It underscores the critical role of inclusive sports programs, adaptive equipment, and policy initiatives in overcoming these barriers and fostering an environment where everyone can enjoy the benefits of sports. Through a comprehensive review of existing research and case studies, the paper also explores specific sports and their suitability for various types of disabilities. It discusses adapted sports like wheelchair basketball, blind soccer, and para-swimming, showcasing how these tailored activities not only accommodate disabilities but also promote excellence and competition at the highest levels. Additionally, the research paper delves into the economic and societal implications of increased sports participation among individuals with disabilities. It explores the potential for greater inclusion in the workforce, reduced healthcare costs, and the fostering of a more inclusive and accepting society. This research paper underscores the profound impact of sports activities on individuals with disabilities, highlighting their potential to improve physical health, mental well-being, and social integration. It calls for continued efforts to break down barriers and promote inclusive sports programs to ensure that everyone, regardless of their abilities, can access the transformative power of sports. Ultimately, this study contributes to a broader understanding of disability and sports, emphasizing the importance of inclusivity and accessibility in creating a more equitable and healthier society.

Keywords: sports and health, sports and disability, curing disability through sports, health benefits of sports

Procedia PDF Downloads 42

Authors: Bahaa Eldin A. Fouda, Khaled N. Yossef, Mohamed Elhosseny, Ahmed Lotfy, Mohamed Salama, Mohamed Sobh

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Developmental neurotoxicity (DNT) entails the toxic effects imparted by various chemicals on the brain during the early childhood period. As human brains are vulnerable during this period, various chemicals would have their maximum effects on brains during early childhood. Some toxicants have been confirmed to induce developmental toxic effects on CNS e.g. lead, however; most of the agents cannot be identified with certainty due the defective nature of predictive toxicology models used. A novel alternative method that can overcome most of the limitations of conventional techniques is the use of 3D neurospheres system. This in-vitro system can recapitulate most of the changes during the period of brain development making it an ideal model for predicting neurotoxic effects. In the present study, we verified the possible DNT of epoxomicin which is a naturally occurring selective proteasome inhibitor with anti-inflammatory activity. Rat neural progenitor cells were isolated from rat embryos (E14) extracted from placental tissue. The cortices were aseptically dissected out from the brains of the fetuses and the tissues were triturated by repeated passage through a fire-polished constricted Pasteur pipette. The dispersed tissues were allowed to settle for 3 min. The supernatant was, then, transferred to a fresh tube and centrifuged at 1,000 g for 5 min. The pellet was placed in Hank’s balanced salt solution cultured as free-floating neurospheres in proliferation medium. Two doses of epoxomicin (1µM and 10µM) were used in cultured neuropsheres for a period of 14 days. For proliferation analysis, spheres were cultured in proliferation medium. After 0, 4, 5, 11, and 14 days, sphere size was determined by software analyses. The diameter of each neurosphere was measured and exported to excel file further to statistical analysis. For viability analysis, trypsin-EDTA solution were added to neurospheres for 3 min to dissociate them into single cells suspension, then viability evaluated by the Trypan Blue exclusion test. Epoxomicin was found to affect proliferation and viability of neuropsheres, these effects were positively correlated to doses and progress of time. This study confirms the DNT effects of epoxomicin on 3D neurospheres model. The effects on proliferation suggest possible gross morphologic changes while the decrease in viability propose possible focal lesion on exposure to epoxomicin during early childhood.

Keywords: neural progentor cells, epoxomicin, neurosphere, medical and health sciences

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Authors: Elsadig Naseraddeen Ahmed Mohamed

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In contrast to the uncertainty and complementary principle, it will be shown in the present paper that the probability of the simultaneous occupation event of any definite values of coordinates by any definite values of momentum and energy at any definite instance of time can be described by a binary definite function equivalent to the difference between their numbers of occupation and evacuation epochs up to that time and also equivalent to the number of exchanges between those occupation and evacuation epochs up to that times modulus two, these binary definite quantities can be defined at all point in the time’s real-line so it form a binary signal represent a complete mechanical description of physical reality, the time of these exchanges represent the boundary of occupation and evacuation epochs from which we can calculate these binary signals using the fact that the time of universe events actually extends in the positive and negative of time’s real-line in one direction of extension when these number of exchanges increase, so there exists noninvertible transformation matrix can be defined as the matrix multiplication of invertible rotation matrix and noninvertible scaling matrix change the direction and magnitude of exchange event vector respectively, these noninvertible transformation will be called actual transformation in contrast to information transformations by which we can navigate the universe’s events transformed by actual transformations backward and forward in time’s real-line, so these information transformations will be derived as an elements of a group can be associated to their corresponded actual transformations. The actual and information model of the universe will be derived by assuming the existence of time instance zero before and at which there is no coordinate occupied by any definite values of momentum and energy, and then after that time, the universe begin its expanding in spacetime, this assumption makes the need for the existence of Laplace’s demon who at one moment can measure the positions and momentums of all constituent particle of the universe and then use the law of classical mechanics to predict all future and past of universe’s events, superfluous, we only need for the establishment of our analog to digital converters to sense the binary signals that determine the boundaries of occupation and evacuation epochs of the definite values of coordinates relative to its origin by the definite values of momentum and energy as present events of the universe from them we can predict approximately in high precision it's past and future events.

Keywords: binary-signal mechanics, actual-information model of the universe, actual-transformation, information-transformation, uncertainty principle, Laplace's demon

Procedia PDF Downloads 161

Authors: R. M. Shabbir Ahmed, Mohamed Haneef, A. R. Anwar Khan

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Analysis of stresses plays important role in the optimization of structures. Prior stress estimation helps in better design of the products. Composites find wide usage in the industrial and home applications due to its strength to weight ratio. Especially in the air craft industry, the usage of composites is more due to its advantages over the conventional materials. Composites are mainly made of orthotropic materials having unequal strength in the different directions. Composite materials have the drawback of delamination and debonding due to the weaker bond materials compared to the parent materials. So proper analysis should be done to the composite joints before using it in the practical conditions. In the present work, a composite plate with elastic pin is considered for analysis using finite element software Ansys. Basically the geometry is built using Ansys software using top down approach with different Boolean operations. The modelled object is meshed with three dimensional layered element solid46 for composite plate and solid element (Solid45) for pin material. Various combinations are considered to find the strength of the composite joint under uniaxial loading conditions. Due to symmetry of the problem, only quarter geometry is built and results are presented for full model using Ansys expansion options. The results show effect of pin diameter on the joint strength. Here the deflection and load sharing of the pin are increasing and other parameters like overall stress, pin stress and contact pressure are reducing due to lesser load on the plate material. Further material effect shows, higher young modulus material has little deflection, but other parameters are increasing. Interference analysis shows increasing of overall stress, pin stress, contact stress along with pin bearing load. This increase should be understood properly for increasing the load carrying capacity of the joint. Generally every structure is preloaded to increase the compressive stress in the joint to increase the load carrying capacity. But the stress increase should be properly analysed for composite due to its delamination and debonding effects due to failure of the bond materials. When results for an isotropic combination is compared with composite joint, isotropic joint shows uniformity of the results with lesser values for all parameters. This is mainly due to applied layer angle combinations. All the results are represented with necessasary pictorial plots.

Keywords: bearing force, frictional force, finite element analysis, ANSYS

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Authors: Diaa Ahmed Mohamed Ahmedien

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Nowadays, it cannot be denied that the most important interactive arts trends have appeared as a result of significant scientific mutations in the modern sciences, and holographic art is not an exception, where it is considered as a one of the most important major contemporary interactive arts trends in visual arts. Holographic technique had been evoked through the modern physics application in late 1940s, for the improvement of the quality of electron microscope images by Denis Gabor, until it had arrived to Margaret Benyon’s art exhibitions, and then it passed through a lot of procedures to enhance its quality and artistic applications technically and visually more over 70 years in visual arts. As a modest extension to these great efforts, this research aimed to invoke extraordinary attempt to enroll sample of normal people in Egyptian community in holographic recording program to record their appreciated objects or antiques, therefore examine their abilities to interact with modern techniques in visual communication arts. So this research tried to answer to main three questions: 'can we use the analog holographic techniques to unleash new theoretical and practical knowledge in interactive arts for public in Egyptian community?', 'to what extent holographic art can be familiar with public and make them able to produce interactive artistic samples?', 'are there possibilities to build holographic interactive program for normal people which lead them to enhance their understanding to visual communication in public and, be aware of interactive arts trends?' This research was depending in its first part on experimental methods, where it conducted in Laser lab at Cairo University, using Nd: Yag Laser 532 nm, and holographic optical layout, with selected samples of Egyptian people that they have been asked to record their appreciated object, after they had already learned recording methods, and in its second part on a lot of discussion panel had conducted to discuss the result and how participants felt towards their holographic artistic products through survey, questionnaires, take notes and critiquing holographic artworks. Our practical experiments and final discussions have already lead us to say that this experimental research was able to make most of participants pass through paradigm shift in their visual and conceptual experiences towards more interaction with contemporary visual arts trends, as an attempt to emphasize to the role of mature relationship between the art, science and technology, to spread interactive arts out in our community through the latest scientific and artistic mutations around the world and the role of this relationship in our societies particularly with those who have never been enrolled in practical arts programs before.

Keywords: Egyptian community, holographic art, laser art, visual art

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Authors: Ahmed Al Ansari, Khalid Al Khalifa

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Objective: Multisource feedback (MSF), also called the 360-Degree evaluation is an evaluation process by which questionnaires are distributed amongst medical peers and colleagues to assess physician performance from different sources other than the attending or the supervising physicians. The aim of this study was to design, implement, and evaluate a 360-Degree process in assessing emergency physicians trainee in the Kingdom of Bahrain. Method: The study was undertaken in Bahrain Defense Force Hospital which is a military teaching hospital in the Kingdom of Bahrain. Thirty emergency physicians (who represent the total population of the emergency physicians in our hospital) were assessed in this study. We developed an instrument modified from the Physician achievement review instrument PAR which was used to assess Physician in Alberta. We focused in our instrument to assess professionalism, communication skills and collaboration only. To achieve face and content validity, table of specification was constructed and a working group was involved in constructing the instrument. Expert opinion was considered as well. The instrument consisted of 39 items; were 15 items to assess professionalism, 13 items to assess communication skills, and 11 items to assess collaboration. Each emergency physicians was evaluated with 3 groups of raters, 4 Medical colleague emergency physicians, 4 medical colleague who are considered referral physicians from different departments, and 4 Coworkers from the emergency department. Independent administrative team was formed to carry on the responsibility of distributing the instruments and collecting them in closed envelopes. Each envelope was consisted of that instrument and a guide for the implementation of the MSF and the purpose of the study. Results: A total of 30 emergency physicians 16 males and 14 females who represent the total number of the emergency physicians in our hospital were assessed. The total collected forms is 269, were 105 surveys from coworkers working in emergency department, 93 surveys from medical colleague emergency physicians, and 116 surveys from referral physicians from different departments. The total mean response rates were 71.2%. The whole instrument was found to be suitable for factor analysis (KMO = 0.967; Bartlett test significant, p<0.00). Factor analysis showed that the data on the questionnaire decomposed into three factors which counted for 72.6% of the total variance: professionalism, collaboration, and communication. Reliability analysis indicated that the instrument full scale had high internal consistency (Cronbach’s α 0.98). The generalizability coefficients (Ep2) were 0.71 for the surveys. Conclusions: Based on the present results, the current instruments and procedures have high reliability, validity, and feasibility in assessing emergency physicians trainee in the emergency room.

Keywords: MSF system, emergency, validity, generalizability

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Authors: Ahmed Tamer AlMotasem, Jens Bergström, Anders Gåård, Pavel Krakhmalev, Thijs Jan Holleboom

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In sheet metal forming processes, accumulation and transfer of sheet material to tool surfaces, often referred to as galling, is the major cause of tool failure. Initiation of galling is assumed to occur due to local adhesive wear between two surfaces. Therefore, reducing adhesion between the tool and the work sheet has a great potential to improve the tool materials galling resistance. Experimental observations and theoretical studies show that the presence of primary micro-sized carbides and/or nitrides in alloyed steels may significantly improve galling resistance. Generally, decreased adhesion between the ceramic precipitates and the sheet material counter-surface are attributed as main reason to the latter observations. On the other hand, adhesion processes occur at an atomic scale and, hence, fundamental understanding of galling can be obtained via atomic scale simulations. In the present study, molecular dynamics simulations are used, with utilizing second nearest neighbor embedded atom method potential to investigate the influence of nano-sized cementite precipitates embedded in tool atoms. The main aim of the simulations is to gain new fundamental knowledge on galling initiation mechanisms. Two tool/work piece configurations, iron/iron and iron-cementite/iron, are studied under dry sliding conditions. We find that the average frictional force decreases whereas the normal force increases for the iron-cementite/iron system, in comparison to the iron/iron configuration. Moreover, the average friction coefficient between the tool/work-piece decreases by about 10 % for the iron-cementite/iron case. The increase of the normal force in the case of iron-cementite/iron system may be attributed to the high stiffness of cementite compared to bcc iron. In order to qualitatively explain the effect of cementite on adhesion, the adhesion force between self-mated iron/iron and cementite/iron surfaces has been determined and we found that iron/cementite surface exhibits lower adhesive force than that of iron-iron surface. The variation of adhesion force with temperature was investigated up to 600 K and we found that the adhesive force, generally, decreases with increasing temperature. Structural analyses show that plastic deformation is the main deformation mechanism of the work-piece, accompanied with dislocations generation.

Keywords: adhesion, cementite, galling, molecular dynamics

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Authors: Sharifullah Ahmed, Sarwar Jahan Md. Yasin

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Shallow foundations on unimproved soft natural soils can undergo a high consolidation and secondary settlement. For low and medium rise building projects on such soil condition, pile foundation may not be cost effective. In such cases an alternative to pile foundations may be shallow strip footings placed on a double layered improved soil system soil. The upper layer of this system is untreated or cement treated compacted sand and underlying layer is natural soft clay. This system will reduce the settlement to an allowable limit. The current research has been conducted with the settlement of a rigid plane-strain strip footing of 2.5 m width placed on the surface of a soil consisting of an untreated or cement treated sand layer overlying a bed of homogeneous soft clay. The settlement of the mentioned shallow foundation has been studied considering both cases with the thicknesses of the sand layer are 0.3 to 0.9 times the width of footing. The response of the clay layer is assumed as undrained for plastic loading stages and drained during consolidation stages. The response of the sand layer is drained during all loading stages. FEM analysis was done using PLAXIS 2D Version 8.0. A natural clay deposit of 15 m thickness and 18 m width has been modeled using Hardening Soil Model, Soft Soil Model, Soft Soil Creep Model, and upper improvement layer has been modeled using only Hardening Soil Model. The groundwater level is at the top level of the clay deposit that made the system fully saturated. Parametric study has been conducted to determine the effect of thickness, density, cementation of the sand mat and density, shear strength of the soft clay layer on the settlement of strip foundation under the uniformly distributed vertical load of varying value. A set of the chart has been established for designing shallow strip footing on the sand mat over thick, soft clay deposit through obtaining the particular thickness of sand mat for particular subsoil parameter to ensure no punching shear failure and no settlement beyond allowable level. Design guideline in the form of non-dimensional charts has been developed for footing pressure equivalent to medium-rise residential or commercial building foundation with strip footing on soft inorganic Normally Consolidated (NC) soil of Bangladesh having void ratio from 1.0 to 1.45.

Keywords: design charts, ground improvement, PLAXIS 2D, primary and secondary settlement, sand mat, soft clay

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Authors: Christopher Pullen

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This paper explores the significance of British cinema in the late 1950s and early 1960s as offering a renaissance of realist discourse, in the representation of everyday social issues. Offering a rejection of Hollywood cinema and the superficially of the middle classes, these ‘kitchen sink dramas’ often set within modest and sometimes squalid domestic and social environments, focused on the political struggle of the disenfranchised examining poverty, the oppressed and the outsider. While films like Look Back in Anger and Room at the Top looked primarily at male heterosexual subjectivity, films like A Taste of Honey and Victim focused on female and queer male narratives. Framing the urban landscape as a discursive architectural arena, representing basic living conditions and threatening social worlds, these iconic films established new storytelling processes for the outsider. This paper examines this historical context foregrounding the contemporary films Beautiful Thing (Hettie Macdonald, 1996), Weekend (Andrew Haigh, 2011) and Pride (Marcus Warchus, 2014), while employing the process of textual analysis in relation to theories of affect, defined by writers such as Lisa U. Marks and Sara Ahmed. Considering both romance narratives and public demonstrations of unity, where the queer ‘affective’ body is placed within architectural and social space, Beautiful Thing tells the story of gay male teenagers falling in love despite oppression from family and school, Weekend examines a one-night stand between young gay men and the unlikeliness of commitment, but the drive for sensitivity, and Pride foregrounds an historical relationship between queer youth activists and the miner’s union, who were on strike between 1984-5. These films frame the queer ‘affective’ body within politicized public space, evident in lower class men’s working clubs, tenement housing and brutal modernist tower blocks, focusing on architectural features such as windows, doorways and staircases, relating temporality, desire and change. Through such an examination a hidden history of gay male performativity is revealed, framing the potential of contemporary cinema to focus on the context of the outsider in encouraging social change.

Keywords: queer, affect, cinema, architecture, life chances

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Authors: Ahmed O. Apampa, Yinusa A. Jimoh

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The potential economic viability and environmental benefits of using a biomass waste, such as corn cob ash (CCA) as pozzolan in stabilizing soils for road pavement construction in a sub-tropical region was investigated. Corn cob was obtained from Maya in South West Nigeria and processed to ash of characteristics similar to Class C Fly Ash pozzolan as specified in ASTM C618-12. This was then blended with ordinary Portland cement in the CCA:OPC ratios of 1:1, 1:2 and 2:1. Each of these blends was then mixed with lateritic soil of ASHTO classification A-2-6(3) in varying percentages from 0 – 7.5% at 1.5% intervals. The soil-CCA-Cement mixtures were thereafter tested for geotechnical index properties including the BS Proctor Compaction, California Bearing Ratio (CBR) and the Unconfined Compression Strength Test. The tests were repeated for soil-cement mix without any CCA blending. The cost of the binder inputs and optimal blends of CCA:OPC in the stabilized soil were thereafter analyzed by developing algorithms that relate the experimental data on strength parameters (Unconfined Compression Strength, UCS and California Bearing Ratio, CBR) with the bivariate independent variables CCA and OPC content, using Matlab R2011b. An optimization problem was then set up minimizing the cost of chemical stabilization of laterite with CCA and OPC, subject to the constraints of minimum strength specifications. The Evolutionary Engine as well as the Generalized Reduced Gradient option of the Solver of MS Excel 2010 were used separately on the cells to obtain the optimal blend of CCA:OPC. The optimal blend attaining the required strength of 1800 kN/m2 was determined for the 1:2 CCA:OPC as 5.4% mix (OPC content 3.6%) compared with 4.2% for the OPC only option; and as 6.2% mix for the 1:1 blend (OPC content 3%). The 2:1 blend did not attain the required strength, though over a 100% gain in UCS value was obtained over the control sample with 0% binder. Upon the fact that 0.97 tonne of CO2 is released for every tonne of cement used (OEE, 2001), the reduced OPC requirement to attain the same result indicates the possibility of reducing the net CO2 contribution of the construction industry to the environment ranging from 14 – 28.5% if CCA:OPC blends are widely used in soil stabilization, going by the results of this study. The paper concludes by recommending that Nigeria and other developing countries in the sub-tropics with abundant stock of biomass waste should look in the direction of intensifying the use of biomass waste as fuel and the derived ash for the production of pozzolans for road-works, thereby reducing overall green house gas emissions and in compliance with the objectives of the United Nations Framework on Climate Change.

Keywords: corn cob ash, biomass waste, lateritic soil, unconfined compression strength, CO2 emission

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Authors: Jeh Patel, Chandrahas Paidi, Ahmed Hambaba

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Traditional methods for analyzing athlete movement often lack the detail and immediacy required for optimal training. This project aims to address this limitation by developing a Real-time human pose estimation system specifically designed to enhance athlete training across various sports. This system leverages the power of convolutional neural networks (CNNs) to provide a comprehensive and immediate analysis of an athlete’s movement patterns during training sessions. The core architecture utilizes dilated convolutions to capture crucial long-range dependencies within video frames. Combining this with the robust encoder-decoder architecture to further refine pose estimation accuracy. This capability is essential for precise joint localization across the diverse range of athletic poses encountered in different sports. Furthermore, by quantifying movement efficiency, power output, and range of motion, the system provides data-driven insights that can be used to optimize training programs. Pose estimation data analysis can also be used to develop personalized training plans that target specific weaknesses identified in an athlete’s movement patterns. To overcome the limitations posed by outdoor environments, the project employs strategies such as multi-camera configurations or depth sensing techniques. These approaches can enhance pose estimation accuracy in challenging lighting and occlusion scenarios, where pose estimation accuracy in challenging lighting and occlusion scenarios. A dataset is collected From the labs of Martin Luther King at San Jose State University. The system is evaluated through a series of tests that measure its efficiency and accuracy in real-world scenarios. Results indicate a high level of precision in recognizing different poses, substantiating the potential of this technology in practical applications. Challenges such as enhancing the system’s ability to operate in varied environmental conditions and further expanding the dataset for training were identified and discussed. Future work will refine the model’s adaptability and incorporate haptic feedback to enhance the interactivity and richness of the user experience. This project demonstrates the feasibility of an advanced pose detection model and lays the groundwork for future innovations in assistive enhancement technologies.

Keywords: computer vision, deep learning, human pose estimation, U-NET, CNN

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Authors: Hanadi Mohamed Shawgi Gamal, Ashraf Mohamed Ahmed Abdalla

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Sudan is endowed by a great diversity of tree species; nevertheless, the utilization of wood resources has traditionally concentrated on a few number of species. With the great variation in the climatic zones of Sudan, great variations are expected in the anatomical properties between and within species. This variation needs to be fully explored in order to suggest the best uses for the species. Modern research on wood has substantiated that the climatic condition where the species grow has significant effect on wood properties. Understanding the extent of variability of wood is important because the uses for each kind of wood are related to its characteristics; furthermore, the suitability or quality of wood for a particular purpose is determined by the variability of one or more of these characteristics. The present study demonstrates the effect of rainfall zones in some anatomical properties of Acacia seyal var. seyal growing in Sudan. For this purpose, twenty healthy trees were collected randomly from two zones (ten trees per zone). One zone with relatively low rainfall (273mm annually) which represented by North Kordofan state and White Nile state and the second with relatively high rainfall (701 mm annually) represented by Blue Nile state and South Kordofan state. From each sampled tree, a stem disc (3 cm thick) was cut at 10% from stem height. One radius was obtained in central stem dices. Two representative samples were taken from each disc, one at 10% distance from pith to bark, the second at 90% in order to represent the juvenile and mature wood. The investigated anatomical properties were fibers length, fibers and vessels diameter, lumen diameter, and wall thickness as well as cell proportions. The result of the current study reveals significant differences between zones in mature wood vessels diameter and wall thickness, as well as juvenile wood vessels, wall thickness. The higher values were detected in the drier zone. Significant differences were also observed in juvenile wood fiber length, diameter as well as wall thickness. Contrary to vessels diameter and wall thickness, the fiber length, diameter as well as wall thickness were decreased in the drier zone. No significant differences have been detected in cell proportions of juvenile and mature wood. The significant differences in some fiber and vessels dimension lead to expect significant differences in wood density. From these results, Acacia seyal var. seyal seems to be well adapted with the change in rainfall and may survive in any rainfall zone.

Keywords: Acacia seyal var. seyal, anatomical properties, rainfall zones, variation

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Authors: Elidrissi Laila, El Rhaoussi Fatima-Zahra, Haddad Fouad, Tahiri Mohamed, Hliwa Wafaa, Bellabah Ahmed, Badre Wafaa

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Introduction: Metabolic Dysfunction Associated with Non-Alcoholic Fatty Liver Disease (MASLD), formerly known as Non-Alcoholic Fatty Liver Disease (NAFLD), is the leading cause of chronic liver disease. The cardiometabolic risk factors associated with MASLD represent common health issues and significant public health challenges. Medical students, being active participants in the healthcare system and a young demographic, are particularly relevant for understanding this entity to prevent its occurrence on a personal and collective level. The objective of our study is to assess the level of knowledge among medical students regarding MASLD, its risk factors, and its long-term consequences. Materials and Methods: We conducted a descriptive cross-sectional study using an anonymous questionnaire distributed through social media over a period of 2 weeks. Medical students from various faculties in Morocco answered 22 questions about MASLD, its etiological factors, diagnosis, complications, and principles of treatment. All responses were analyzed using the Jamovi software. Results: A total of 124 students voluntarily provided complete responses. 59% of our participants were in their 3rd year, with a median age of 21 years. Among the respondents, 27% were overweight, obese, or diabetic. 83% correctly answered more than half of the questions, and 77% believed they knew about MASLD. However, 84% of students were unaware that MASLD is the leading cause of chronic liver disease, and 12% even considered it a rare condition. Regarding etiological factors, overweight and obesity were mentioned in 93% of responses, and type 2 diabetes in 84%. 62% of participants believed that type 1 diabetes could not be implicated in MASLD. For 83 students, MASLD was considered a diagnosis of exclusion, while 41 students believed that a biopsy was mandatory for diagnosis. 12% believed that MASLD did not lead to long-term complications, and 44% were unaware that MASLD could progress to hepatocellular carcinoma. Regarding treatment, 85% included weight loss, and 19% did not consider diabetes management as a therapeutic approach for MASLD. At the end of the questionnaire, 89% of the students expressed a desire to learn more about MASLD and were invited to access an informative sheet through a hyperlink. Conclusion: MASLD represents a significant public health concern due to the prevalence of its risk factors, notably the obesity pandemic, which is widespread among the young population. There is a need for awareness about the seriousness of this emerging and long-underestimated condition among young future physicians.

Keywords: MASLD, medical students, obesity, diabetes

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Authors: Vilas Warudkar, Dinkar Janghel, Siraj Ahmed

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Rapid development experienced by India requires huge amount of energy. Actual supply capacity additions have been consistently lower than the targets set by the government. According to World Bank 40% of residences are without electricity. In 12th five year plan 30 GW grid interactive renewable capacity is planned in which 17 GW is Wind, 10 GW is from solar and 2.1 GW from small hydro project, and rest is compensated by bio gas. Renewable energy (RE) and energy efficiency (EE) meet not only the environmental and energy security objectives, but also can play a crucial role in reducing chronic power shortages. In remote areas or areas with a weak grid, wind energy can be used for charging batteries or can be combined with a diesel engine to save fuel whenever wind is available. India according to IEC 61400-1 belongs to class IV Wind Condition; it is not possible to set up wind turbine in large scale at every place. So, the best choice is to go for small scale wind turbine at lower height which will have good annual energy production (AEP). Based on the wind characteristic available at MANIT Bhopal, rotor for small scale wind turbine is designed. Various Aero foil data is reviewed for selection of airfoil in the Blade Profile. Airfoil suited of Low wind conditions i.e. at low Reynold’s number is selected based on Coefficient of Lift, Drag and angle of attack. For designing of the rotor blade, standard Blade Element Momentum (BEM) Theory is implanted. Performance of the Blade is estimated using BEM theory in which axial induction factor and angular induction factor is optimized using iterative technique. Rotor performance is estimated for particular designed blade specifically for low wind Conditions. Power production of rotor is determined at different wind speeds for particular pitch angle of the blade. At pitch 15o and velocity 5 m/sec gives good cut in speed of 2 m/sec and power produced is around 350 Watts. Tip speed of the Blade is considered as 6.5 for which Coefficient of Performance of the rotor is calculated 0.35, which is good acceptable value for Small scale Wind turbine. Simple Load Model (SLM, IEC 61400-2) is also discussed to improve the structural strength of the rotor. In SLM, Edge wise Moment and Flap Wise moment is considered which cause bending stress at the root of the blade. Various Load case mentioned in the IEC 61400-2 is calculated and checked for the partial safety factor of the wind turbine blade.

Keywords: annual energy production, Blade Element Momentum Theory, low wind Conditions, selection of airfoil

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Authors: Gurleen Kour, Mowkshi Khullar, B. K. Chandan, Parvinder Pal Singh, Kushalava Reddy Yumpalla, Gurunadham Munagala, Ram A. Vishwakarma, Zabeer Ahmed

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New chemotherapeutic compounds against multidrug-resistant Mycobacterium tuberculosis (Mtb) are urgently needed to combat drug resistance in tuberculosis (TB). Apart from in-vitro potency against the target, physiochemical properties and pharmacokinetic properties play an imperative role in the process of drug discovery. We have identified novel nitroimidazole derivatives with potential activity against mycobacterium tuberculosis. One lead candidates, MCD-017, which showed potent activity against H37Rv strain (MIC=0.5µg/ml) and was further evaluated in the process of drug development. Methods: Basic physicochemical parameters like solubility and lipophilicity (LogP) were evaluated. Thermodynamic solubility was determined in PBS buffer (pH 7.4) using LC/MS-MS. The partition coefficient (Log P) of the compound was determined between octanol and phosphate buffered saline (PBS at pH 7.4) at 25°C by the microscale shake flask method. The compound followed Lipinski’s rule of five, which is predictive of good oral bioavailability and was further evaluated for metabolic stability. In-vitro metabolic stability was determined in rat liver microsomes. The hepatotoxicity of the compound was also determined in HepG2 cell line. In vivo pharmacokinetic profile of the compound after oral dosing was also obtained using balb/c mice. Results: The compound exhibited favorable solubility and lipophilicity. The physical and chemical properties of the compound were made use of as the first determination of drug-like properties. The compound obeyed Lipinski’s rule of five, with molecular weight < 500, number of hydrogen bond donors (HBD) < 5 and number of hydrogen bond acceptors(HBA) not more then 10. The log P of the compound was less than 5 and therefore the compound is predictive of exhibiting good absorption and permeation. Pooled rat liver microsomes were prepared from rat liver homogenate for measuring the metabolic stability. 99% of the compound was not metabolized and remained intact. The compound did not exhibit cytoxicity in hepG2 cells upto 40 µg/ml. The compound revealed good pharmacokinetic profile at a dose of 5mg/kg administered orally with a half life (t1/2) of 1.15 hours, Cmax of 642ng/ml, clearance of 4.84 ml/min/kg and a volume of distribution of 8.05 l/kg. Conclusion : The emergence of multi drug resistance (MDR) and extensively drug resistant (XDR) Tuberculosis emphasize the requirement of novel drugs active against tuberculosis. Thus, the need to evaluate physicochemical and pharmacokinetic properties in the early stages of drug discovery is required to reduce the attrition associated with poor drug exposure. In summary, it can be concluded that MCD-017 may be considered a good candidate for further preclinical and clinical evaluations.

Keywords: mycobacterium tuberculosis, pharmacokinetics, physicochemical properties, hepatotoxicity

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Authors: Ahmed Borg, Elsa Aristodemou, Attia Attia

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Well control involves managing the circulating drilling fluid within the wells and avoiding kicks and blowouts as these can lead to losses in human life and drilling facilities. Current practices for good control incorporate predictions of pressure losses through computational models. Developing a realistic hydraulic model for a good control problem is a very complicated process due to the existence of a complex multiphase region, which usually contains a non-Newtonian drilling fluid and the miscibility of formation gas in drilling fluid. The current approaches assume an inaccurate flow fluid model within the well, which leads to incorrect pressure loss calculations. To overcome this problem, researchers have been considering the more complex two-phase fluid flow models. However, even these more sophisticated two-phase models are unsuitable for applications where pressure dynamics are important, such as in managed pressure drilling. This study aims to develop and implement new fluid flow models that take into consideration the miscibility of fluids as well as their non-Newtonian properties for enabling realistic kick treatment. furthermore, a corresponding numerical solution method is built with an enriched data bank. The research work considers and implements models that take into consideration the effect of two phases in kick treatment for well control in conventional drilling. In this work, a corresponding numerical solution method is built with an enriched data bank. Software STARCCM+ for the computational studies to study the important parameters to describe wellbore multiphase flow, the mass flow rate, volumetric fraction, and velocity of each phase. Results showed that based on the analysis of these simulation studies, a coarser full-scale model of the wellbore, including chemical modeling established. The focus of the investigations was put on the near drill bit section. This inflow area shows certain characteristics that are dominated by the inflow conditions of the gas as well as by the configuration of the mud stream entering the annulus. Without considering the gas solubility effect, the bottom hole pressure could be underestimated by 4.2%, while the bottom hole temperature is overestimated by 3.2%. and without considering the heat transfer effect, the bottom hole pressure could be overestimated by 11.4% under steady flow conditions. Besides, larger reservoir pressure leads to a larger gas fraction in the wellbore. However, reservoir pressure has a minor effect on the steady wellbore temperature. Also as choke pressure increases, less gas will exist in the annulus in the form of free gas.

Keywords: multiphase flow, well- control, STARCCM+, petroleum engineering and gas technology, computational fluid dynamic

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Authors: E. Rommes, Els Toonen, Rahil Roodsaz, Suborna Camellia, Farhana Alam, Saad Khan, Jhalok Ranjon Talukder, Tanveer Hassan, Syeda Farjana Ahmed, Sabina Faiz Rashid

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In Bangladesh, a country in which adults (both parents and teachers) find it particularly hard to speak with youth about sexuality, adolescents seem to struggle with various insecurities about their sexual feelings, thoughts, behavior and physical characteristics. On the basis of a large number of interviews and focus groups with rural and urban Bangla adolescent girls and boys of lower and middle class as part of the large-scale three-year project ‘Breaking the Shame’, we have identified ten sexual themes or ‘myths’ that youth struggle with most. These encompass amongst others beliefs and insecurities on masturbation, discharge, same-sex behavior and feelings, the effects of watching porn and gender norms. We argue that the Internet is a particularly suitable medium to ‘debunk’ those myths, as youth can consult it anonymously and privately and so avoid social shame. Moreover, amongst the myths, we have identified two kinds which may need different debunking techniques. One kind of myth concerns scientifically uncontested, generally biological related information, such as the effects of having sex with a pregnant woman, questions on the effects of a penile or vaginal discharge or questions on the effects of masturbation. The second kind of myths concerns more diverse information sources and deals with e.g. religious or culturally specific norms, such as on the meaning and existence of homosexuality or gender appropriate norms of behavior in Bangladesh. For addressing both kinds of myths, expert information including a wealth of references to information resources needs to be provided, which the Internet is very suitable for. For the second kind of myths, adolescents also need to learn how to deal with sometimes conflicting norms and information sources, and they need to develop and reflect on their own opinions as part of their identity formation. On the basis of a literature review, we thus distinguish general information needs from identity formation needs, which includes the need to be able to relate information and opinions to one’s own opinions and situation. Hence, we argue that youth not only need abstract expert information to be able to debunk sexual myths, but also the option to discuss this information with other adolescents and compare their own situation and opinions with other peers, who in that way serve as ‘warm experts’ for each other. In this paper, we will describe the outcomes of our qualitative study above. In addition, we will present our findings of an intervention by presenting youth with general, uncontested information on the Internet with additional peer discussion options to compare the debunking effects on different kinds of myths.

Keywords: peer discussion, intervention, sexual myths, shame

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Authors: Md Iqbal Hossain, Tahmeed Ahmed, Kenneth H. Brown

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Objective: To assess the effect of community-based follow up, with or without food-supplementation and/or psychosocial stimulation, as an alternative to current hospital-based follow-up of children with moderate-acute-malnutrition (WHZ < -2 to -3) (MAM). Design/methods: The study was conducted at the ICDDR,B Dhaka Hospital and in four urban primary health care centers of Dhaka, Bangladesh during 2005-2007. The efficacy of five different randomly assigned interventions was compared with respect to the rate of completion of follow-up, growth and morbidity in 227 MAM children aged 6-24 months who were initially treated at ICDDR,B for diarrhea and/or other morbidities. The interventions were: 1) Fortnightly follow-up care (FFC) at the ICDDR,B’s outpatient-unit, including growth monitoring, health education, and micro-nutrient supplementation (H-C, n=49). 2) FFC at community follow-up unit (CNFU) [established in the existing urban primary health-care centers close to the residence of the child] but received the same regimen as H-C (C-C, n=53). 3) As per C-C plus cereal-based supplementary food (SF) (C-SF, n=49). The SF packets were distributed on recruitment and at every visit in CNFU [@1 packet/day for 6–11 and 2 packets/day for 12-24 month old children. Each packet contained 20g toasted rice-powder, 10g toasted lentil-powder, 5g molasses, and 3g soy bean oil, to provide a total of ~ 150kcal with 11% energy from protein]. 4) As per C-C plus psychosocial stimulation (PS) (C-PS, n=43). PS consisted of child-stimulation and parental-counseling conducted by trained health workers. 5) As per C-C plus both SF+PS (C-SF+PS, n=33). Results: A total of 227children (48.5% female), with a mean ± SD age of 12.6 ±3.8 months, and WHZ of - 2.53±0.28 enrolled. Baseline characteristics did not differ by treatment group. The rate of spontaneous attendance at scheduled follow-up visits gradually decreased in all groups. Follow-up attendance and gain in weight and length were greater in groups C-SF, C-SF+PS, and C-PS than C-C, and these indicators were observed least in H-C. Children in the H-C group more often suffered from diarrhea (25 % vs. 4-9%) and fever (28% vs. 8-11%) than other groups (p < 0.05). Children who attended at least five of the total six scheduled follow-up visits gained more in weight (median: 0.86 vs. 0.62 kg, p=0.002), length (median: 2.4 vs. 2.0 cm, p=0.009) than those who attended fewer. Conclusions: Community-based service delivery, especially including supplementary food with or without psychosocial stimulation, permits better rehabilitation of children with MAM compared to current hospital outpatients-based care. By scaling the community-based follow-up including food supplementation with or without psychosocial stimulation, it will be possible to rehabilitate a greater number of MAM children in a better way.

Keywords: community-based management, moderate acute malnutrition, psychosocial stimulation, supplementary food

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Authors: Ahmed Abdallatif

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Background: Patients with malignant germ cell tumors have age distribution in two peaks, with the first one during infancy and the second after the onset of puberty. Gonadal germ cell tumors are the most common malignant ovarian tumor in females aged below twenty years. Sacrococcygeal and retroperitoneal abdominal tumors usually presents in a large size before the onset of symptoms. Methods: Patients with pediatric germ cell tumors presenting to Children’s Cancer Hospital Egypt and National Cancer Institute Egypt from January 2008 to June 2011 Patients underwent stratification according to risk into low, intermediate and high risk groups according to children oncology group classification. Objectives: Assessment of the clinicopathologic features of all cases of pediatric germ cell tumors and classification of malignant cases according to their stage, and the primary site to low, intermediate and high risk patients. Evaluation of surgical management in each group of patients focusing on surgical approach, the extent of surgical resection according to each site, ability to achieve complete surgical resection and perioperative complications. Finally, determination of the three years overall and disease-free survival in different groups and the relation to different prognostic factors including the extent of surgical resection. Results: Out of 131 cases surgically explored only 26 cases had re exploration with 8 cases explored for residual disease 9 cases for remote recurrence or metastatic disease and the other 9 cases for other complications. Patients with low risk kept under follow up after surgery, out of those of low risk group (48 patients) only 8 patients (16.5%) shifted to intermediate risk. There were 20 patients (14.6%) diagnosed as intermediate risk received 3 cycles of compressed (Cisplatin, Etoposide and Bleomycin) and all high risk group patients 69patients (50.4%) received chemotherapy. Stage of disease was strongly and significantly related to overall survival with a poorer survival in late stages (stage IV) as compared to earlier stages. Conclusion: Overall survival rate at 3 three years was (76.7% ± 5.4, 3) years EFS was (77.8 % ±4.0), however 3 years DFS was much better (89.8 ± 3.4) in whole study group with ovarian tumors had significantly higher Overall survival (90% ± 5.1). Event Free Survival analysis showed that Male gender was 3 times likely to have bad events than females. Patients who underwent incomplete resection were 4 times more than patients with complete resection to have bad events. Disease free survival analysis showed that Patients who underwent incomplete surgery were 18.8 times liable for recurrence compared to those who underwent complete surgery, and patients who were exposed to re-excision were 21 times more prone to recurrence compared to other patients.

Keywords: extragonadal, germ cell tumors, gonadal, pediatric

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Authors: Ram V. Mohan, John Rivas-Murillo, Ahmed Mohamed, Wayne D. Hodo

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Cementitious materials, an excellent example of highly complex, heterogeneous material systems, are cement-based systems that include cement paste, mortar, and concrete that are heavily used in civil infrastructure; though commonly used are one of the most complex in terms of the material morphology and structure than most materials, for example, crystalline metals. Processes and features occurring at the nanometer sized morphological structures affect the performance, deformation/failure behavior at larger length scales. In addition, cementitious materials undergo chemical and morphological changes gaining strength during the transient hydration process. Hydration in cement is a very complex process creating complex microstructures and the associated molecular structures that vary with hydration. A fundamental understanding can be gained through multi-scale level modeling for the behavior and properties of cementitious materials starting from the material chemistry level atomistic scale to further explore their role and the manifested effects at larger length and engineering scales. This predictive modeling enables the understanding, and studying the influence of material chemistry level changes and nanomaterial additives on the expected resultant material characteristics and deformation behavior. Atomistic-molecular dynamic level modeling is required to couple material science to engineering mechanics. Starting at the molecular level a comprehensive description of the material’s chemistry is required to understand the fundamental properties that govern behavior occurring across each relevant length scale. Material chemistry level models and molecular dynamics modeling and simulations are employed in our work to describe the molecular-level chemistry features of calcium-silicate-hydrate (CSH), one of the key hydrated constituents of cement paste, their associated deformation and failure. The molecular level atomic structure for CSH can be represented by Jennite mineral structure. Jennite has been widely accepted by researchers and is typically used to represent the molecular structure of the CSH gel formed during the hydration of cement clinkers. This paper will focus on our recent work on the shear and compressive deformation and failure behavior of CSH represented by Jennite mineral structure that has been widely accepted by researchers and is typically used to represent the molecular structure of CSH formed during the hydration of cement clinkers. The deformation and failure behavior under shear and compression loading deformation in traditional hydrated CSH; effect of material chemistry changes on the predicted stress-strain behavior, transition from linear to non-linear behavior and identify the on-set of failure based on material chemistry structures of CSH Jennite and changes in its chemistry structure will be discussed.

Keywords: cementitious materials, deformation, failure, material chemistry modeling

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Authors: Belaynesh Tefera, Ahmed Mohammed, Zelalem Bayisa

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This study focuses on the issue of underage internal migration from rural to urban areas in Ethiopia, specifically in the context of child labor. It addresses the significant disparities in living standards between rural and urban areas, which motivate individuals from rural areas to migrate to urban areas in search of better economic opportunities. The study was conducted in Addis Ababa, where there is a high prevalence of underage internal migrants engaged in child labor due to extreme poverty in rural parts of the country. The aim of this study is to explore the life experiences of shoe-makers who have migrated from rural areas of Ethiopia to Addis Ababa. The focus is on understanding the factors that push these underage individuals to migrate, the challenges they face, and the implications for child labor. This study adopts a qualitative approach, using semistructured face-to-face interviews with underage migrants. A total of 27 interviews were conducted in Addis Ababa, Ethiopia, until the point of data saturation. The criteria for selecting interviewees include working as shoemakers and migrating to Addis Ababa underage, below 16 years old. The interviews were audio-taped, transcribed into Amharic, and then translated into English for analysis. The study reveals that the major push factors for underage internal migration are socioeconomic and environmental factors. Despite improvements in living standards for underage migrants and their families, there is a high prevalence of child labor and lack of access to education among them. Most interviewees migrated without the accompaniment of their family members and faced various challenges, including sleeping on the streets. This study highlights the role of social marketing in addressing the issues of underage internal migration and child labor. It suggests that social marketing can be an effective strategy to protect children from abuse, loneliness, and harassment during their migration process. The data collection involved conducting in-depth interviews with the underage migrants. The interviews were transcribed and translated for analysis. The analysis focused on identifying common themes and patterns within the interview data. The study addresses the factors contributing to underage internal migration, the challenges faced by underage migrants, the prevalence of child labor, and the potential role of social marketing in addressing these issues. The study concludes that although Ethiopia has policies against child internal migration, it is difficult to protect underage laborers who migrate from rural to urban areas due to the voluntary nature of their migration. The study suggests that social marketing can serve as a solution to protect children from abuse and other challenges faced during migration.

Keywords: underage, internal migration, social marketing, child labor, Ethiopia

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Authors: Ibrahim Rassoul, A. Serir, E-K. Si Ahmed, J. Legrand

Abstract:

The acronym PEM refers to Proton Exchange Membrane or alternatively Polymer Electrolyte Membrane. Due to its high efficiency, low operating temperature (30–80 °C), and rapid evolution over the past decade, PEMFCs are increasingly emerging as a viable alternative clean power source for automobile and stationary applications. Before PEMFCs can be employed to power automobiles and homes, several key technical challenges must be properly addressed. One technical challenge is elucidating the mechanisms underlying water transport in and removal from PEMFCs. On one hand, sufficient water is needed in the polymer electrolyte membrane or PEM to maintain sufficiently high proton conductivity. On the other hand, too much liquid water present in the cathode can cause “flooding” (that is, pore space is filled with excessive liquid water) and hinder the transport of the oxygen reactant from the gas flow channel (GFC) to the three-phase reaction sites. The experimental transparent fuel cell used in this work was designed to represent actual full scale of fuel cell geometry. According to the operating conditions, a number of flow regimes may appear in the microchannel: droplet flow, blockage water liquid bridge /plug (concave and convex forms), slug/plug flow and film flow. Some of flow patterns are new, while others have been already observed in PEMFC microchannels. An algorithm in MATLAB was developed to automatically determine the flow structure (e.g. slug, droplet, plug, and film) of detected liquid water in the test microchannels and yield information pertaining to the distribution of water among the different flow structures. A video processing algorithm was developed to automatically detect dynamic and static liquid water present in the gas channels and generate relevant quantitative information. The potential benefit of this software allows the user to obtain a more precise and systematic way to obtain measurements from images of small objects. The void fractions are also determined based on images analysis. The aim of this work is to provide a comprehensive characterization of two-phase flow in an operating fuel cell which can be used towards the optimization of water management and informs design guidelines for gas delivery microchannels for fuel cells and its essential in the design and control of diverse applications. The approach will combine numerical modeling with experimental visualization and measurements.

Keywords: polymer electrolyte fuel cell, air-water two phase flow, gas diffusion layer, microchannels, advancing contact angle, receding contact angle, void fraction, surface tension, image processing

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