Search results for: time difference between fajr and new moon

Authors: Hao Min Chuah, Tatsuya Yamazaki, Ryosui Iwasawa, Tatsumi Suto

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In recent years, with the advancement of digital technology, the movement to introduce so-called ICT (Information and Communication Technology), such as computer technology and network technology, to civil engineering construction sites and construction sites is accelerating. As part of this movement, attempts are being made in various situations to reproduce actual sites inside computers and use them for designing and construction planning, as well as for training inexperienced engineers. The installation of wave-dissipating blocks on coasts, etc., is a type of work that has been carried out by skilled workers based on their years of experience and is one of the tasks that is difficult for inexperienced workers to carry out on site. Wave-dissipating blocks are structures that are designed to protect coasts, beaches, and so on from erosion by reducing the energy of ocean waves. Wave-dissipating blocks usually weigh more than 1 t and are installed by being suspended by a crane, so it would be time-consuming and costly for inexperienced workers to train on-site. In this paper, therefore, a block installation simulator is developed based on Unity 3D, a game development engine. The simulator computes porosity. Porosity is defined as the ratio of the total volume of the wave breaker blocks inside the structure to the final shape of the ideal structure. Using the evaluation of porosity, the simulator can determine how well the user is able to install the blocks. The voxelization technique is used to calculate the porosity of the structure, simplifying the calculations. Other techniques, such as raycasting and box overlapping, are employed for accurate simulation. In the near future, the simulator will install an automatic block installation algorithm based on combinatorial optimization solutions and compare the user-demonstrated block installation and the appropriate installation solved by the algorithm.

Keywords: 3D simulator, porosity, user interface, voxelization, wave-dissipating blocks

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Authors: Saeeda Batool, Ather Maqsood Ahmed

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This study investigates the impact of public healthcare facilities and socio-economic circumstances on the status of child health in Pakistan. The complete analysis is carried out in correspondence with fourth and sixth millennium development goals. Further, the health variables chosen are also inherited from targeted indicators of the mentioned goals (MDGs). Trends in the Human Opportunity Index (HOI) for both health inequalities and coverage are analyzed using the Pakistan Social and Living Standards Measurement (PLSM) data set for 2001-02 to 2012-13 at the national and provincial level. To reveal the relative importance of each circumstance in achieving the targeted values for child health, Shorrocks decomposition is applied on HOI. The annual point average growth rate of HOI is used to simulate the time period for the achievement of target set by MDGs and universal access also. The results indicate an improvement in HOI for a reduction in child mortality rates from 52.1% in 2001-02 to 67.3% in 2012-13, which confirms the availability of healthcare opportunities to a larger segment of society. Similarly, immunization against measles and other diseases such as Diphtheria, Polio, Bacillus Calmette-Guerin (BCG), and Hepatitis has also registered an improvement from 51.6% to 69.9% during the period of study at the national level. On a positive note, no gender disparity has been found for child health indicators and that health outcome is mostly affected by the parental and geographical features and availability of health infrastructure. However, the study finds that this achievement has been uneven across provinces. Pakistan is not only lagging behind in achieving its health goals, disappointingly with the current rate of health care provision, but it will take many additional years to achieve its targets.

Keywords: socio-economic circumstances, unmet MDGs, public healthcare services, child and infant mortality

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Authors: S. Wakim, M. Nemer, B. Zeghondy, B. Ghannam, C. Bouallou

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Designing the optimal heat exchanger is still an essential objective to be achieved. Parametrical optimization involves the evaluation of the heat exchanger dimensions to find those that best satisfy certain objectives. This method contributes to an enhanced design rather than an optimized one. On the contrary, topology optimization finds the optimal structure that satisfies the design objectives. The huge development in metal additive manufacturing allowed topology optimization to find its way into engineering applications especially in the aerospace field to optimize metal structures. Using topology optimization in 3d heat and mass transfer problems requires huge computational time, therefore coupling it with CFD simulations can reduce this it. However, existed CFD models cannot be coupled with topology optimization. The CFD model must allow creating a uniform mesh despite the initial geometry complexity and also to swap the cells from fluid to solid and vice versa. In this paper, a porous media approach compatible with topology optimization criteria is developed. It consists of modeling the fluid region of the heat exchanger as porous media having high porosity and similarly the solid region is modeled as porous media having low porosity. The switching from fluid to solid cells required by topology optimization is simply done by changing each cell porosity using a user defined function. This model is tested on a plate and fin heat exchanger and validated by comparing its results to experimental data and simulations results. Furthermore, this model is used to perform a material reallocation based on local criteria to optimize a plate and fin heat exchanger under a constant heat duty constraint. The optimized fin uses 20% fewer materials than the first while the pressure drop is reduced by about 13%.

Keywords: computational methods, finite element method, heat exchanger, porous media, topology optimization

Procedia PDF Downloads 160

Authors: Aymen Laadhari

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During the last decade, an increasing number of contributions have been made in the fields of scientific computing and numerical methodologies applied to the study of the hemodynamics in the heart. In contrast, the numerical aspects concerning the interaction of pulsatile blood flow with highly deformable thin leaflets have been much less explored. This coupled problem remains extremely challenging and numerical difficulties include e.g. the resolution of full Fluid-Structure Interaction problem with large deformations of extremely thin leaflets, substantial mesh deformations, high transvalvular pressure discontinuities, contact between leaflets. Although the Lagrangian description of the structural motion and strain measures is naturally used, many numerical complexities can arise when studying large deformations of thin structures. Eulerian approaches represent a promising alternative to readily model large deformations and handle contact issues. We present a fully Eulerian finite element methodology tailored for the simulation of pulsatile blood flow in the aorta and sinus of Valsalva interacting with highly deformable thin leaflets. Our method enables to use a fluid solver on a fixed mesh, whilst being able to easily model the mechanical properties of the valve. We introduce a semi-implicit time integration scheme based on a consistent NewtonRaphson linearization. A variant of the classical Newton method is introduced and guarantees a third-order convergence. High-fidelity computational geometries are built and simulations are performed under physiological conditions. We address in detail the main features of the proposed method, and we report several experiments with the aim of illustrating its accuracy and efficiency.

Keywords: eulerian, level set, newton, valve

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Authors: Mateusz Frydrych

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The construction of diaphragm walls as excavation shoring as well as part of deep foundations is widely used in geotechnical engineering. Today's design challenges lie in the optimal dimensioning of the cross-section, which is demanded by technological considerations. Also in force is the issue of optimization and sustainable use of construction materials, including reduction of carbon footprint, which is currently a relevant challenge for the construction industry. The author presents the concept of an approach to achieving increased efficiency of diaphragm wall excavation shoring by using structural compression technology. The author proposes to implement prestressed tendons in a non-linear manner in the reinforcement cage. As a result bending moment is reduced, which translates into a reduction in the amount of steel needed in the section, a reduction in displacements, and a reduction in the scratching of the casing, including the achievement of better tightness. This task is rarely seen and has not yet been described in a scientific way in the literature. The author has developed a dynamic numerical model that allows the dimensioning of the cross-section of a prestressed shear wall, as well as the study of casing displacements and cross-sectional forces in any defined computational situation. Numerical software from the Sofistik - open source development environment - was used for the study, and models were validated in Plaxis software . This is an interesting idea that allows for optimizing the execution of construction works and reducing the required resources by using fewer materials and saving time. The author presents the possibilities of a prestressed diaphragm wall, among others, using. The example of a diaphragm wall working as a cantilever at the height of two underground floors without additional strutting or stability protection by using ground anchors. This makes the execution of the work more criminal for the contractor and, as a result, cheaper for the investor.

Keywords: prestressed diaphragm wall, Plaxis, Sofistik, innovation, FEM, optimisation

Procedia PDF Downloads 81

Authors: Eda Jazexhiu-Postoli, Gladiola Hoxha, Ada Simeoni, Sonila Biba

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Background Neonatal hypotonia represents a commonly encountered issue in the Neonatal Intensive Care Unit and newborn nursery. The differential diagnosis is broad, encompassing chromosome abnormalities, primary muscular dystrophies, neuropathies and inborn errors of metabolism. Aim of study Our study describes some of the main clinical features of hypotonia in newborns and presents clinical cases of neonatal hypotonia we treated in our Neonatal unit in the last 3 years. Case reports Four neonates born in our hospital presented with hypotonia after birth, one preterm newborn 35-36 weeks of gestational age and three other term newborns (38-39 weeks of gestational age). Prenatal data revealed a decrease in fetal movements in both cases. Intrapartum meconium-stained amniotic fluid was found in 75% of our hypotonic newborns. Clinical features included inability to establish effective respiratory movements and need for resuscitation in the delivery room, respiratory distress syndrome, feeding difficulties and need for oro-gastric tube feeding, dysmorphic features, hoarse voice and moderate to severe muscular hypotonia. The genetic workup revealed the diagnosis of Autosomal Recessive Congenital Myasthenic Syndrome 1-B, Sotos Syndrome, Spinal Muscular Atrophy Type 1 and Transient Hypotonia of the Newborn. Two out of four hypotonic neonates were transferred to the Pediatric Intensive Care Unit and died at the age of three to five months old. Conclusion Hypotonia is a concerning finding in neonatal care and it is suggested by decreased intrauterine fetal movements, failure to establish first breaths, respiratory distress and feeding difficulties in the neonate. Prognosis is determined by its etiology and time of diagnosis and intervention.

Keywords: hypotonic neonate, respiratory distress, feeding difficulties, fetal movements

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Authors: Ana Neves, John Leander, Ignacio Gonzalez, Raid Karoumi

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Systematic monitoring and inspection are needed to assess the present state of a structure and predict its future condition. If an irregularity is noticed, repair actions may take place and the adequate intervention will most probably reduce the future costs with maintenance, minimize downtime and increase safety by avoiding the failure of the structure as a whole or of one of its structural parts. For this to be possible decisions must be made at the right time, which implies using systems that can detect abnormalities in their early stage. In this sense, Structural Health Monitoring (SHM) is seen as an effective tool for improving the safety and reliability of infrastructures. This paper explores the decision-making problem in SHM regarding the maintenance of civil engineering structures. The aim is to assess the present condition of a bridge based exclusively on measurements using the suggested method in this paper, such that action is taken coherently with the information made available by the monitoring system. Artificial Neural Networks are trained and their ability to predict structural behavior is evaluated in the light of a case study where acceleration measurements are acquired from a bridge located in Stockholm, Sweden. This relatively old bridge is presently still in operation despite experiencing obvious problems already reported in previous inspections. The prediction errors provide a measure of the accuracy of the algorithm and are subjected to further investigation, which comprises concepts like clustering analysis and statistical hypothesis testing. These enable to interpret the obtained prediction errors, draw conclusions about the state of the structure and thus support decision making regarding its maintenance.

Keywords: artificial neural networks, clustering analysis, model-free damage detection, statistical hypothesis testing, structural health monitoring

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Authors: Danila Zuffetti, Lorenzo Chiesa

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Background: A hospice narrative interview aims at putting the sick at the core of disease and treatment allowing them to explore their most intimate facets. The aim of this work is to favor authentic narration by leading towards awareness and acceptance of terminality and to face death with serenity. Narration in palliative care aims at helping to reduce the chaos generated by the disease and to elaborate interpretations on the course of reality, besides, the narration delivered to the doctor is fundamental and communicates the meaning given to symptoms. Methods: The narrative interview has become a regular activity in the Castellini Foundation since 2017. Patients take part every week, and for more days, in one hour sessions, in a welcoming and empathic setting and the interaction with the operator leads to a gradual awareness of their terminality. Patients are submitted with free answer questions with the purpose of facilitating and stimulating self-narration. Narration has not always been linear, but patients are left free to shift in time to revisit their disease process by making use of different tools, such as digital storytelling. Results: The answers provided by the patients show to which extent the narrative interview is an instrument allowing the analysis of the stories and gives the possibility to better understand and deepen the different implications of patient and caregiver’s background. Conclusion: The narration work in the hospice demonstrates that narrative medicine is an added value. This instrument has proven useful not only in the support of patients but also for the palliative doctor to identify wishes for accompanying them to the end with dignity and serenity. The narrative interview favors the construction of an authentic therapeutic relationship. The sick are taken wholly in charge, and they are guaranteed a high quality of life until their very last instant.

Keywords: construction of an authentic therapy relationship, gradual awareness of their terminality, narrative interview, reduce the chaos generated by the desease

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Authors: Helen Pluut, Remus Ilies, Nikos Dimotakis, Maral Darouei

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This study aims to examine recovery from work as an important daily activity with implications for workplace behavior. Building on affective events theory and the stressor-detachment model as frameworks, this paper proposes and tests a comprehensive within-individual model that uncovers the role of recovery processes at home in linking workplace demands (e.g., workload) and stressors (e.g., workplace incivility) to next-day organizational citizenship behaviors (OCBs). Our sample consisted of 126 full-time employees in a large Midwestern University. For a period of 16 working days, these employees were asked to fill out 3 electronic surveys while at work. The first survey (sent out in the morning) measured self-reported sleep quality, recovery experiences the previous day at home, and momentary effect. The second survey (sent out close to the end of the workday) measured job demands and stressors as well as OCBs, while the third survey in the evening assessed job strain. Data were analyzed using Hierarchical Linear Modeling (HLM). Results indicated that job demands and stressors at work made it difficult to unwind properly at home and have a good night’s sleep, which had repercussions for next day’s morning effect, which, in turn, influenced OCBs. It can be concluded that processes of recovery are vital to an individual’s daily effective functioning and behavior at work, but recovery may become impaired after a hard day’s work. Thus, our study sheds light on the potentially persistent nature of strain experienced as a result of work and points to the importance of recovery processes to enable individuals to avoid such cross-day spillover. Our paper will discuss this implication for theory and practice as well as potential directions for future research.

Keywords: affect, job demands, organizational citizenship behavior, recovery, strain

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Authors: Sumeyra Sevim, Gulsum Gizem Topal, Mercan Merve Tengilimoglu-Metin, Banu Sancak, Mevlude Kizil

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Aflatoxin M1 (AFM1) represents mutagenic, carcinogenic, hepatotoxic and immunosuppressive properties, and shows adverse effect on human health. Recently the use of probiotics are focused on AFM1 detoxification because of the fact that probiotic strains have a binding ability to AFM1. Moreover, inulin is a prebiotic to improve the ability of probiotic bacteria. Therefore, the aim of the study is to investigate the effect of inulin on AFM1 binding ability of some probiotic bacteria. Yoghurt samples were manufactured by using skim milk powder artificially contaminated with AFM1 at concentration 100 pg/ml. Different samples were prepared for the study as: first sample consists of yoghurt starter bacteria (L. bulgaricus and S. thermophilus), the second sample consists of starter and L. plantarum, starter and B. bifidum ATCC were added to the third sample, starter and B. animalis ATCC 27672 were added to the forth sample, and the fifth sample is a binary culture consisted of starter and B. bifidum and B. animalis. Moreover, the same work groups were prepared with inulin (4%). The samples were incubated at 42°C for 4 hours, then stored for three different time interval (1,5 and 10 days). The toxin was measured by the ELISA. When inulin was added to work groups, there was significant change on AFM1 binding ability at least one sample in all groups except the one with L. plantarum (p<0.05). The highest levels of AFM1 binding ability (68.7%) in samples with inulin were found in the group which B. bifidum was added, whereas the lowest levels of AFM1 binding ability (44.4%) in samples with inulin was found in the fifth sample. The most impressive effect of inulin was found on B.bifidum. In this study, it was obtained that there was a significant effect of storage on AFM1 binding ability in the all groups with inulin except the one with L. plantarum (p<0.05). Consequently, results show that AFM1 detoxification by probiotics have a potential application to reduce toxin concentrations in yoghurt. Besides, inulin has different effects on AFM1 binding ability of each probiotic bacteria strain.

Keywords: aflatoxin M1, inulin, probiotics, storage

Procedia PDF Downloads 319

Authors: Abdul-Rahman Al-Ali

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As the number of mobile devices is growing exponentially, it is estimated to connect about 50 million devices to the Internet by the year 2020. At the end of this decade, it is expected that an average of eight connected devices per person worldwide. The 50 billion devices are not mobile phones and data browsing gadgets only, but machine-to-machine and man-to-machine devices. With such growing numbers of devices the Internet of Things (I.o.T) concept is one of the emerging technologies as of recently. Within the smart grid technologies, smart home appliances, Intelligent Electronic Devices (IED) and Distributed Energy Resources (DER) are major I.o.T objects that can be addressable using the IPV6. These objects are called the smart grid internet of things (SG-I.o.T). The SG-I.o.T generates big data that requires high-speed computing infrastructure, widespread computer networks, big data storage, software, and platforms services. A company’s utility control and data centers cannot handle such a large number of devices, high-speed processing, and massive data storage. Building large data center’s infrastructure takes a long time, it also requires widespread communication networks and huge capital investment. To maintain and upgrade control and data centers’ infrastructure and communication networks as well as updating and renewing software licenses which collectively, requires additional cost. This can be overcome by utilizing the emerging computing paradigms such as cloud computing. This can be used as a smart grid enabler to replace the legacy of utilities data centers. The talk will highlight the role of I.o.T, cloud computing services and their development models within the smart grid technologies.

Keywords: intelligent electronic devices (IED), distributed energy resources (DER), internet, smart home appliances

Procedia PDF Downloads 327

Authors: Edison A. Bonifaz

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In this work, a numerical procedure is proposed to design dense multi-material structures using the Directed Energy Deposition (DED) process. A thermo-mechanical finite element model to predict thermal cycles and residual stresses is presented. A numerical layer build-up procedure coupled with a moving heat flux was constructed to minimize strains and residual stresses that result in the multi-layer deposition of an AISI 316 austenitic steel on an AISI 304 austenitic steel substrate. To simulate the DED process, the automated interface of the ABAQUS AM module was used to define element activation and heat input event data as a function of time and position. Of this manner, the construction of ABAQUS user-defined subroutines was not necessary. Thermal cycles and thermally induced stresses created during the multi-layer deposition metal AM pool crystallization were predicted and validated. Results were analyzed in three independent metal layers of three different experiments. The one-way heat and material deposition toolpath used in the analysis was created with a MatLab path script. An optimal combination of feedstock and heat input printing parameters suitable for fabricating multi-material dense structures in the directed energy deposition metal AM process was established. At constant power, it can be concluded that the lower the heat input, the lower the peak temperatures and residual stresses. It means that from a design point of view, the one-way heat and material deposition processing toolpath with the higher welding speed should be selected.

Keywords: event series, thermal cycles, residual stresses, multi-pass welding, abaqus am modeler

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Authors: Konstantinos G. Kostinakis, Manthos K. Papadopoulos, Asimina M. Athanatopoulou

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An important area of research in seismic risk analysis is the evaluation of expected seismic damage of structures under a specific earthquake ground motion. Several conventional intensity measures of ground motion have been used to estimate their damage potential to structures. Yet, none of them was proved to be able to predict adequately the seismic damage of any structural system. Therefore, alternative advanced intensity measures which take into account not only ground motion characteristics but also structural information have been proposed. The adequacy of a number of advanced earthquake intensity measures in prediction of structural damage of 3D R/C buildings under seismic excitation which attacks the building with arbitrary incident angle is investigated in the present paper. To achieve this purpose, a symmetric in plan and an asymmetric 5-story R/C building are studied. The two buildings are subjected to 20 bidirectional earthquake ground motions. The two horizontal accelerograms of each ground motion are applied along horizontal orthogonal axes forming 72 different angles with the structural axes. The response is computed by non-linear time history analysis. The structural damage is expressed in terms of the maximum interstory drift as well as the overall structural damage index. The values of the aforementioned seismic damage measures determined for incident angle 0° as well as their maximum values over all seismic incident angles are correlated with 9 structure-specific ground motion intensity measures. The research identified certain intensity measures which exhibited strong correlation with the seismic damage of the two buildings. However, their adequacy for estimation of the structural damage depends on the response parameter adopted. Furthermore, it was confirmed that the widely used spectral acceleration at the fundamental period of the structure is a good indicator of the expected earthquake damage level.

Keywords: damage indices, non-linear response, seismic excitation angle, structure-specific intensity measures

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Authors: Ayeshmanthe Rathnayake, Siew Goh, Carmel Fenton, Ashutosh Hardikar

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Post-Operative Atrial Fibrillation (POAF) is the most frequent complication of cardiac surgery and is associated with reduced survival, increased rates of cognitive changes and cerebrovascular accident, heart failure, renal dysfunction, infection and length of stay, and hospital costs. Cardiac tamponade, although less common, carries high morbidity and mortality. Shed mediastinal blood in the pericardial space is a major source of intrapericardial oxidative stress and inflammation that triggers POAF. The utilisation of a left posterior pericardiotomy aims to shunt blood from the pericardium into the pleural space and have a role in the prevention of POAF as well as cardiac tamponade. 2118 patients had undergone isolated Coronary Artery Bypass Graft (CABG) at Royal Hobart Hospital from 2008-2021. They were divided into pericardiotomy vs control group. Patient baseline demographics, intraoperative data, and post-operative outcomes were reviewed retrospectively. Total incidence of new POAF and cardiac tamponade was 26.1% and 0.75%, respectively. Primary outcome of both the incidence of POAF(22.9% vs27.8%OR 0.77 p<0.05) and Cardiac Tamponade (0% vs 1.1% OR 0.85 p<0.05) were less in the pericardiotomy group.Increasing age, BMI, poor left ventricular function (EF <30%), and return to theatre were independent predictors of developing POAF. There were similar rates of return to theatre for bleeding however, no cases of tamponade in the pericardiotomy group. There were no complications attributable to left posterior pericardiotomy and the time added to the duration of surgery was minimal. Left posterior pericardiotomy is associated with a significant reduction in the incidence of POAFand cardiac tamponade and issafe and efficient.

Keywords: cardiac surgery, pericardiotomy, post-operative atrial fibrillation, cardiac tamponade

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Authors: S. Redjala, N. Ait Hocine, M. Gratton, N. Poirot, R. Ferhoum, S. Azem

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Polycarbonate (PC) is a promising polymer with high transparency in the range of the visible spectrum and is used in various fields, for example medical, electronic, automotive. Its low weight, chemical inertia, high impact resistance and relatively low cost are of major importance. In recent decades, some materials such as metals and ceramics have been replaced by polymers because of their superior advantages. However, some characteristics of the polymers are highly modified under the effect of ultraviolet (UV) radiation and temperature. The changes induced in the material by such aging depend on the exposure time, the wavelength of the UV radiation and the temperature level. The UV energy is sufficient to break the chemical bonds leading to a cleavage of the molecular chains. This causes changes in the mechanical, thermal, optical and morphological properties of the material. The present work is focused on the study of the effects of aging under ultraviolet (UV) radiation and under different temperature values on the physical-chemical and mechanical properties of a PC. Thus, various investigations, such as FTIR and XRD analyses, SEM and optical microscopy observations, micro-hardness measurements and monotonic and cyclic tensile tests, were carried out on the PC in the initial state and after aging. Results have shown the impact of aging on the properties of the PC studied. In fact, the MEB highlighted changes in the superficial morphology of the material by the presence of cracks and material de-bonding in the form of debris. The FTIR spectra reveal an attenuation of the peaks like the hydroxyl (OH) groups located at 3520 cm-1. The XRD lines shift towards a larger angle, reaching a maximum of 3°. In addition, Vickers micro-hardness measurements show that aging affects the surface and the core of the material, which results in different mechanical behaviours under monotonic and cyclic tensile tests. This study pointed out effects of aging on the macroscopic properties of the PC studied, in relationship with its microstructural changes.

Keywords: mechanical properties, physical-chemical properties, polycarbonate, UV aging, temperature aging

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Authors: Paul J Yazaki, Michael Bouvet, John Shively

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Surgery for solid gastrointestinal (GI) cancers such as pancreatic, colorectal, and gastric adenocarcinoma remains the mainstay of curative therapy. Complete resection of the primary tumor with negative margins (R0 resection), its draining lymph nodes, and distant metastases offers the optimal surgical benefit. Real-time fluorescence guided surgery (FGS) promises to improve GI cancer outcomes and is rapidly advancing with tumor-specific antibody conjugated fluorophores that can be imaged using near infrared (NIR) technology. Carcinoembryonic Antigen (CEA) is a non-internalizing tumor antigen validated as a surface tumor marker expressed in >95% of colorectal, 80% of gastric, and 60% of pancreatic adenocarcinomas. Our humanized anti-CEA hT84.66-M5A (M5A) monoclonal antibody (mAb)was conjugated with the NHS-IRDye800CW fluorophore and shown it can rapidly and effectively NIRoptical imageorthotopically implanted human colon and pancreatic cancer in mouse models. A limitation observed is that these NIR-800 dye conjugated mAbs have a rapid clearance from the blood, leading to a narrow timeframe for FGS and requiring high doses for effective optical imaging. We developed a novel antibody-fluorophore conjugate by incorporating a PEGylated sidearm linker to shield or mask the IR800 dye’s hydrophobicity which effectively extended the agent’s blood circulation half-life leading to increased tumor sensitivity and lowered normal hepatic uptake. We hypothesized that our unique anti-CEA linked to the fluorophore, IR800 by PEGylated sidewinder, M5A-SW-IR800 will become the next generation optical imaging agent, safe, effective, and widely applicable for intraoperative image guided surgery in CEA expressing GI cancers.

Keywords: optical imaging, anti-CEA, cancer, fluorescence-guided surgery

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Authors: Abdulkarim Yusuf

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Motivation: The Nigerian economy has seen significant macroeconomic instability, fuelled mostly by an overreliance on fluctuating oil revenues. The rising disparity between tax receipts and government spending in Nigeria necessitates government borrowing to fund the anticipated pace of economic growth. Rising public debt and fiscal sustainability are limiting the government's ability to invest in key infrastructure that promotes private investment and growth in Nigeria. Objective: This paper fills an empirical research vacuum by examining the impact of public debt on fiscal sustainability in Nigeria, given the significance of fiscal stability in decreasing poverty and the constraints that an unsustainable debt burden imposes on it. Data and method: Annual time series data covering the period 1980 to 2022 exposed to conventional and structural breaks stationarity tests and the Autoregressive Distributed Lag estimation approach were adopted for this study. Results: The results reveal that domestic debt stock, debt service payment, foreign reserve stock, exchange rate, and private investment all had a major adverse effect on fiscal stability in the long and short run, corroborating the debt overhang and crowding-out hypothesis. External debt stock, prime lending rate, and degree of trade openness, which boosted fiscal stability in the long run, had a major detrimental effect on fiscal stability in the short run, whereas foreign direct investment inflows had an important beneficial impact on fiscal stability in both the long and short run. Implications: The results indicate that fiscal measures that inspire domestic resource mobilization, sustainable debt management techniques, and dependence on external debt to boost deficit financing will improve fiscal stability and drive growth.

Keywords: ARDL co-integration, debt overhang, debt servicing, fiscal stability, public debt

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Authors: Md. Z. Alam, Amal A. Elgharbawy, Muhammad Moniruzzaman, Nassereldeen A. Kabbashi, Parveen Jamal

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The enzymatic hydrolysis of lignocellulosic biomass is one of the obstacles in the process of sugar production, due to the presence of lignin that protects the cellulose molecules against cellulases. Although the pretreatment of lignocellulose in ionic liquid (IL) system has been receiving a lot of interest; however, it requires IL removal with an anti-solvent in order to proceed with the enzymatic hydrolysis. At this point, introducing a compatible cellulase enzyme seems more efficient in this process. A cellulase enzyme that was produced by Trichoderma reesei on palm kernel cake (PKC) exhibited a promising stability in several ILs. The enzyme called PKC-Cel was tested for its optimum pH and temperature as well as its molecular weight. One among evaluated ILs, 1,3-diethylimidazolium dimethyl phosphate [DEMIM] DMP was applied in this study. Evaluation of six factors was executed in Stat-Ease Design Expert V.9, definitive screening design, which are IL/ buffer ratio, temperature, hydrolysis retention time, biomass loading, cellulase loading and empty fruit bunches (EFB) particle size. According to the obtained data, IL-enzyme system shows the highest sugar concentration at 70 °C, 27 hours, 10% IL-buffer, 35% biomass loading, 60 Units/g cellulase and 200 μm particle size. As concluded from the obtained data, not only the PKC-Cel was stable in the presence of the IL, also it was actually stable at a higher temperature than its optimum one. The reducing sugar obtained was 53.468±4.58 g/L which was equivalent to 0.3055 g reducing sugar/g EFB. This approach opens an insight for more studies in order to understand the actual effect of ILs on cellulases and their interactions in the aqueous system. It could also benefit in an efficient production of bioethanol from lignocellulosic biomass.

Keywords: cellulase, hydrolysis, lignocellulose, pretreatment

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Authors: Euripides Antoniades

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In 1821, the Greek Revolution movement, under the political influence that arose from the French revolution, and the corresponding movements in Italy, Germany and America, demanded the liberation of the nation and the establishment of an independent national state. Published topics in the British press regarding the Greek Revolution, focused on: a)the right of the Greeks to claim their freedom from Turkish domination in order to establish an independent state based on the principle of national autonomy, b)criticism regarding Turkish rule as illegal and the power of the Ottoman Sultan as arbitrary, c)the recognition of the Greek identity and its distinction from the Turkish one and d)the endorsement Greeks as the descendants of ancient Greeks. The London Times is a print publication that presents, in chronological or thematic order, the news, opinions or announcements about the most important events that have occurred in a place during a specified period of time. A combination of qualitative and quantitative content analysis was applied. An attempt was made to record Greek Revolution references along with the usage of specific words and expressions that contribute to the representation of the historical events and their exposure to the reading public. Key finds of this research reveal that a)there was a frequency of passionate daily articles concerning the events in Greece, their length, and context in The Times of London, b)he British public opinion was influenced by this particular newspaper and c) he newspaper published various news about the revolution by adopting the role of animator of the Greek struggle. In fact, this type of news was the main substance of the The London Times’ structure, establishing a positive image about the Greek Revolution contributing to the European diplomatic development. These factors offered a change in the attitude of the British and Russians respectively assuming a positive approach towards Greece.

Keywords: Greece, revolution, press, the london times, great britain, mass media

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Authors: Srinivas Vangari

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In the era of big data, ensuring the accuracy, consistency, and reliability of critical data assets is crucial for data-driven enterprises. Master Data Management (MDM) plays a crucial role in this endeavor. This paper investigates the role of Artificial Intelligence (AI) in enhancing MDM, focusing on how AI-driven solutions can automate and optimize various stages of the master data lifecycle. By integrating AI (Quantitative and Qualitative Analysis) into processes such as data creation, maintenance, enrichment, and usage, organizations can achieve significant improvements in data quality and operational efficiency. Quantitative analysis is employed to measure the impact of AI on key metrics, including data accuracy, processing speed, and error reduction. For instance, our study demonstrates an 18% improvement in data accuracy and a 75% reduction in duplicate records across multiple systems post-AI implementation. Furthermore, AI’s predictive maintenance capabilities reduced data obsolescence by 22%, as indicated by statistical analyses of data usage patterns over a 12-month period. Complementing this, a qualitative analysis delves into the specific AI-driven strategies that enhance MDM practices, such as automating data entry and validation, which resulted in a 28% decrease in manual errors. Insights from case studies highlight how AI-driven data cleansing processes reduced inconsistencies by 25% and how AI-powered enrichment strategies improved data relevance by 24%, thus boosting decision-making accuracy. The findings demonstrate that AI significantly enhances data quality and integrity, leading to improved enterprise performance through cost reduction, increased compliance, and more accurate, real-time decision-making. These insights underscore the value of AI as a critical tool in modern data management strategies, offering a competitive edge to organizations that leverage its capabilities.

Keywords: artificial intelligence, master data management, data governance, data quality

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Authors: Nwafia Ifeyinwa Nkeiruka, Nwafia Walter Chukwuma

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Since the early 1980’s fungi have emerged as major causes of human diseases, especially among immunocompromised. The most commonly isolated yeast is Candida albicans and constitutes the 4th most common nosocomial BSI in humans. It is progressive and cumulative and become more complex over time.It can even lead to leaky gut syndrome that causes food and environmental allergies. It is worthy of note that all the available data on oral Candida risk factors in humans were documented essentially using data from studies conducted in other areas, hence there is need for comparative and complementary information from the South eastern part of Nigeria. Method: 200 subjects of all age groups of both sexes were randomly examined,by swabbing their palatine mucosa and dorsal tongue with sterile cotton wool,then cultured into Sabouraud dextrose agar plates supplemented with antibiotics and incubated aerobically at 37 degree for 48 hrs. Identification of Candida albicans was done by germ tubes tests, chlamydospores production on cornmeal agar supplemented with 1% Tween 80.Sugar and nitrogen assimilation test using API 20C Auxanogram and potassium nitrate agar. Results: Out of 30 samples that were positive for candida, 15 (50%) were candida albicans. Using the anova test (P < 0.05) this variation is significant (P = 0016). followed by C. dublinensis 3 (13%), C. tropicalis 3 (10%), C. pseudotropicalis 3 (10%), C, glabrata 2 (7%), C. parapsilosis 2 (7%) and lastly C. krusei 1 (3%).However, 53% of the patients were female while 47% were male. Among the HIV positive isolates.67% were HIV isolates not on drugs while 33% positives isolates were on drugs and the percentages of candida species in these patients were as follows C. albicans were 45% followed by C. glabrata and C.tropicalis which were 17% each, C.parapsilosis, C.dubliensis and C.pseudotropicalis were all 8% each. Conclusion: Oral Candidiasis is a marker of systemic diseases and in some cases, it may be the first clinical presentation. There is need for more intensive clinical and laboratory monitoring and possible early intervention to prevent the reoccurrence and resistance to treatment.

Keywords: oral cavity, Candida species, oral Candidiasis, risk factors

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Authors: Hassen Mohammed, Michelle Clarke, Helen Marshall

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Maternal immunization is an effective strategy to protect pregnant women and their offspring from vaccine-preventable diseases. Despite the recommendation of maternal influenza and more recently pertussis immunization in Australia, uptake of these vaccines has been suboptimal. Monitoring the impact of the current funded vaccine programs for pregnant women is limited. The study aimed to assess the impact of the funded program and determine factors associated with vaccine uptake in pregnant women. This observational prospective study was undertaken between November 2014 and July 2016 at the Women’s and Children’s Hospital in South Australia (WCH). Demographic details and vaccination history from South Australian pregnant women who attended the WCH were reviewed. A standardized self-reported survey was conducted in antenatal care with a follow up telephone interview at 8-10 weeks post-delivery. A midwife delivered immunization program for pregnant women in antenatal clinic commenced in April 2015. Of the 180 pregnant women who completed the survey questionnaire, 75.5% and 80.5 % received maternal influenza and pertussis vaccines respectively. First-time mothers had twice the odds of having received influenza vaccine during pregnancy than multiparous women (OR 2.4; CI 1.14 - 4.94; p= 0.021). The proportion of women who received pertussis vaccine during pregnancy, following the introduction of the midwife delivered pertussis vaccination program (140/155, 90.3%) was significantly higher compared with women who received maternal pertussis vaccination prior to the introduction of the program (5/22, 23.7%, p < 0.001). The odds of women receiving maternal pertussis vaccine following the implementation of the midwife delivered program were 31 times higher than women who delivered babies prior to the program (OR 31.7, CI 10.24- 98.27; p < 0.001). High uptake of influenza and pertussis vaccines during pregnancy can be attained with health care provider recommendation and inclusion of maternal immunization as part of standard antenatal care.

Keywords: influenza, maternal immunization, pertussis, provider recommendation

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Authors: Irina Bondarenko, Olga Vandina

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The theory of evolutionary economics is the basis for preparation and application of methods forming the stock market infrastructure development concept. The authors believe that the basis for the process of formation and development of the stock market model infrastructure in Russia is the theory of large systems. This theory considers the financial market infrastructure as a whole on the basis of macroeconomic approach with the further definition of its aims and objectives. Evaluation of the prospects for interaction of securities market institutions will enable identifying the problems associated with the development of this system. The interaction of elements of the stock market infrastructure allows to reduce the costs and time of transactions, thereby freeing up resources of market participants for more efficient operation. Thus, methodology of the transaction analysis allows to determine the financial infrastructure as a set of specialized institutions that form a modern quasi-stable system. The financial infrastructure, based on international standards, should include trading systems, regulatory and supervisory bodies, rating agencies, settlement, clearing and depository organizations. Distribution of financial assets, reducing the magnitude of transaction costs, increased transparency of the market are promising tasks in the solution for questions of services level and quality increase provided by institutions of the securities market financial infrastructure. In order to improve the efficiency of the regulatory system, it is necessary to provide "standards" for all market participants. The development of a clear regulation for the barrier to the stock market entry and exit, provision of conditions for the development and implementation of new laws regulating the activities of participants in the securities market, as well as formulation of proposals aimed at minimizing risks and costs, will enable the achievement of positive results. The latter will be manifested in increasing the level of market participant security and, accordingly, the attractiveness of this market for investors and issuers.

Keywords: institutional infrastructure, financial assets, regulatory system, stock market, transparency of the market

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Authors: Davoud Maleki, Neda Zamani

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The purpose of this research was to investigate the factors affecting the organizational pathology of knowledge production in Islamic Azad University. The present research method is quantitative. It was a survey type and applied research in terms of its purpose. The statistical population of the present study included all full-time professors of the Islamic Azad Universities in the North, South, East, West and Central regions, including the Islamic Azad Universities of Sari, Isfahan, Kerman, Khorramabad and Shiraz, and their total number was 1389, based on the Cochran formula. 305 people were selected as the sample size by random sampling method. The research tool was a researcher-made questionnaire, whose validity was calculated from the professors' point of view and its reliability was calculated based on Cronbach's alpha and was 0.89. For data analysis, confirmatory factor analysis and structural equations were used with Smart3 Pls software. The findings showed that the variables of strategy, structure and process directly and the variable of strategy explained indirectly through the variables of structure and process 96.8% of the pathology of knowledge production. Also, structure 49.6% and process variable 58.4% explain the pathology of knowledge production. 38% of knowledge production changes related to the direct effect of strategy, 39% of knowledge production changes Related to the effect of structure, 32% of the changes in knowledge production are related to the direct effect of the process, 70.5% of the changes related to the structure are related to the direct effect of the strategy, 36.5% of the changes related to the process are related to the direct effect of the strategy, 46.3 Percentage of process variable changes It is related to the direct effect of the structure. According to the obtained results, it can be acknowledged that the pathology model of knowledge production in Islamic Azad University can be used as an effective model in the pathology of knowledge production and can improve the scientific level of knowledge producers.

Keywords: pathology of knowledge production, strategic issues, process issues, Islamic Azad University

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Authors: Muhammad Hardyan Prastyanto, Aisah Azhari Marwangi, Yulinda Rizky Pratiwi

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Globalization has become a driving force for the current technological developments. The presence of the Virtual Space provides opportunities for people to self-actualization through access to a wider world, quickly and easily. Cities that are part of the existence of life, witness the history of civilization over time, also has been the major object to upgrading on technological sector. A smart city is one where the government and citizenry are using the best available means, including ICT, to achieve their shared goals. This often includes economic development, environmental sustainability, and improved quality of life for citizens. Thus theory is the basis for research of this study. This study aimed to know the implementation of the Urban Retrofitting at Malioboro area based on Information and Communication Technologies. The method of this study is by reviewing the effectiveness of the E-commerce uses as a major system to identification the Malioboro Smart Central Business District. By using a significance level of 5 %, it can be concluded that addresses have a significant influence on the ratings obtained, namely regarding the location of the hotel establishment. But despite the use of the website does not have a significant influence on the rating of the hotel, using the website still has influence significantly on the rating, because the p -value (Sig.) of the variable website is not so much different from the significance level determined by the researcher. In the interpretation, if a hotel is located on the Pasar Kembang streets and not to use the website, so the hotel is likely to have a rating of the constant value which is 3.183. However, if a hotel located on the Sosrowijayan streets, so the hotel rating will be increased by 0,302. Then if a hotel has been using a website, so the hotel rating will increase by 0,264. It is possible to conclude the effectiveness of ICT’s (Website) uses and location to identification the urban retrofitting through increasing of building rating in Malioboro Central Business District.

Keywords: urban retrofitting, e-commerce, information and communication technology, statistic regression, SCBD, Malioboro

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Authors: Gargi Ghoshal, Ashay Jain, Deepika Thakur, U. S. Shivhare, O. P. Katare

Abstract:

The main objectives of this work were the rheological characterization of dispersions, emulsions at different pH used in the microcapsules preparation and the microcapsules obtain from gum arabic (A), guar gum (G), casein (C) and whey protein isolate (W) to keep β-carotene protected from degradation using the complex coacervation microencapsulation technique (CCM). The evaluation of rheological properties of dispersions, emulsions of different pH and so obtained microencapsules manifest the changes occur in the molecular structure of wall materials during the encapsulation process of β-carotene. These dispersions, emulsions of different pH and formulated microencapsules were subjected to go through various conducted experiments (flow curve test, amplitude sweep, and frequency sweep test) using controlled stress dynamic rheometer. Flow properties were evaluated as a function of apparent viscosity under steady shear rate ranging from 0.1 to 100 s-1. The frequency sweep test was conducted to determine the extent of viscosity and elasticity present in the samples at constant strain under changing angular frequency range from 0.1 to 100 rad/s at 25ºC. The dispersions and emulsion exhibited a shear thinning non-Newtonian behavior whereas microencapsules are considered as shear-thickening respectively. The apparent viscosity for dispersion, emulsions were decreased at low shear rates 20 s-1 and for microencapsules, it decreases up to ~50 s-1 besides these value, it has shown constant pattern. Oscillatory shear experiments showed a predominant viscous liquid behavior up to crossover frequencies of dispersions of C, W, A at 49.47 rad/s, 57.60 rad/s and 21.45 rad/s emulsion sample of AW at pH 5.0 it was 17.85 rad/s and GW microencapsules 61.40 rad/s respectively whereas no such crossover was found in G dispersion, emulsion with C and microencapsules still it showed more viscous behavior. Storage and loss modulus decreases with time also a shift of the crossover towards lower frequencies for A, W and C was observed respectively. However, their microencapsules showed more viscous behavior as compared to samples prior to blending.

Keywords: viscosity, gums, proteins, frequency sweep test, apparent viscosity

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Authors: Abbas Pourreza

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MicroRNAs (miRNAs) are small single-stranded non-coding RNAs. They are almost 18-25 nucleotides long and very conservative through evolution. They are involved in adjusting the expression of numerous genes due to the existence of a complementary region, generally in the 3' untranslated regions (UTR) of target genes, against particular mRNAs in the cell. Also, miRNAs have been proven to be involved in cell development, differentiation, proliferation, and apoptosis. More than 2000 miRNAs have been recognized in human cells, and these miRNAs adjust approximately one-third of all genes in human cells. Dysregulation of miRNA originated from abnormal DNA methylation patterns of the locus, cause to down-regulated or overexpression of miRNAs, and it may affect tumor formation or development of it. Breast cancer (BC) is the most commonly identified cancer, the most prevalent cancer (23%), and the second-leading (14%) mortality in all types of cancer in females. BC can be classified based on the status (+/−) of the hormone receptors, including estrogen receptor (ER), progesterone receptor (PR), and the Receptor tyrosine-protein kinase erbB-2 (ERBB2 or HER2). Currently, there are four main molecular subtypes of BC: luminal A, approximately 50–60 % of BCs; luminal B, 10–20 %; HER2 positive, 15–20 %, and 10–20 % considered Basal (triple-negative breast cancer (TNBC)) subtype. Aberrant expression of miR-145, miR-21, miR-10b, miR-125a, and miR-206 was detected by Stem-loop real-time RT-PCR in BC cases. Breast tumor formation and development may result from down-regulation of a tumor suppressor miRNA such as miR-145, miR-125a, and miR-206 and/or overexpression of an oncogenic miRNA such as miR-21 and miR-10b. MiR-125a, miR-206, miR-145, miR-21, and miR-10b are hugely predicted to be new tumor markers for the diagnosis and prognosis of BC. MiR-21 and miR-125a could play a part in the treatment of HER-2-positive breast cancer cells, while miR-145 and miR-206 could speed up the evolution of cure techniques for TNBC. To conclude, miRNAs will be presented as hopeful molecules to be used in the primary diagnosis, prognosis, and treatment of BC and battle as opposed to its developed drug resistance.

Keywords: breast cancer, HER2 positive, miRNA, TNBC

Procedia PDF Downloads 99

Authors: B. A. Alabadan, E. S. Ajayi, C. A. Okolo

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The storage losses recorded globally in maize (Zea mays) especially in the developing countries is worrisome. Certain degenerating changes in the physical characteristics (PC) of the grain occur due to the interaction between the stored maize and the immediate environment especially during long storage period. There has been tremendous reduction in the storage losses since the evolution of metallic silos. This study was carried out to assess the physical quality attributes of maize stored in 2500 MT and 1 MT metallic silos for a period of eight months. The PC evaluated includes percentage moisture content MC, insect damage ID, foreign matters FM, hectolitre weight HC, mould M and germinability VG. The evaluation of data obtained was done using statistical package for social sciences (SPSS 20) for windows evaluation version to determine significant levels and trend of deterioration (P < 0.05) for all the values obtained using Multiple Analysis of Variance (MANOVA) and Duncan’s multivariate test. The result shows that the PC are significant with duration of storage at (P < 0.05) except MI and FM that are significant at (P > 0.05) irrespective of the size of the metallic silos. The average mean deviation for physical properties from the control in respect to duration of storage are as follows: MC 10.0 ±0.00%, HC 72.9 ± 0.44% ID 0.29 ± 0.00%, BG 0.55±0.05%, MI 0.00 ± 0.65%, FM 0.80± 0.20%, VG 100 ± 0.03%. The variables that were found to be significant (p < 0.05) with the position of grain in the bulk are VG, MI and ID while others are insignificant at (p > 0.05). Variables were all significant (p < 0.05) with the duration of storage with (0.00) significant levels, irrespective of the size of the metallic silos, but were insignificant with the position of the grain in the bulk (p > 0.05). From the results, it can be concluded that there is a slight decrease of the following variables, with time, HC, MC, and V, probably due to weather fluctuations and grain respiration, while FM, BG, ID and M were found to increase slightly probably due to insect activity in the bigger silos and loss of moisture. The size of metallic silos has no remarkable influence on the PC of stored maize (Zea mays). Germinability was found to be better with the 1 MT silos probably due to its hermetic nature. Smaller size metallic silos are preferred for storage of seeds but bigger silos largely depend on the position of the grains in the bulk.

Keywords: maize, storage, silo, physical characteristics

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Authors: Ezra N. S. Lockhart

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The number of children diagnosed with autism spectrum disorder (ASD) has increased approximately 173% during the last decade making ASD the fastest growing developmental disability in the United States. This rise in prevalence rates indeed has an effect on schools. ASD is overwhelmingly the most reported primary special education eligibility category for students accessing special education, at a national average of 61.3%. ASD is regarded as an urgent public health concern at an estimated annual per capita cost of $3.2 million. Furthermore, considering that ASD is a lifelong disorder estimated lifetime per capita cost reach $35 billion. The resources available to special education programs are insufficient to meet the educational needs of the 6.4 million students receiving special educational services. This is especially true given that there has been and continues to be a chronic shortage of fully certified special education teachers for decades. Reports indicate that 81.1% of students with special needs spend 40% or more in general education classrooms. Regardless of whether support is implemented in the special education or general education classroom the resource demand is obvious. Schools are actively seeking to implement low-cost alternatives and budget saving measures in response to this demand. In public school settings, programs such as Applied Behavior Analysis are challenging to implement and fund at $40,000 per student per year. As an alternative, computer-based interventions are inexpensive, less time-consuming to implement, and require minimal teacher or paraprofessional training to administer. Affordability, pricing schemes, availability, and compatibility of computer-based interventions that support social and emotional skill development in individuals with ASD are discussed.

Keywords: affordability, autism spectrum disorder, computer-based intervention, emotional skills, social skills

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Authors: Ana Carolina Lima, Carlos Sérgio Agostinho, Amadeu M. V. M. Soares, Kieran A. Monaghan

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Neotropical freshwaters host some of the most biodiverse ecosystems in the world and are among the most threatened by habitat alterations. The high number of species and lack of basic ecological knowledge provides a major obstacle to understanding the effects of environmental change. We assessed the impact of dam closure on the fish communities of a neotropical river by applying simple descriptions of community organizations: Species Abundance Distribution (SAD) and Abundance Biomass Comparison (ABC) curves. Fish data were collected during three distinct time periods (one year before, one year after and five years after closure), at eight sites located downstream of the dam, in the reservoir and reservoir transition zone and upstream of the regulated flow. Dam closure was associated with changes in the structural and functional organization of fish communities at all sites. Species richness tended to increase immediately after dam closure while evenness decreased. Changes in taxonomic structure were accompanied by a change in the distribution of biomass with the proportionate contribution by smaller individuals significantly increased relative to larger individuals. Five years on, richness had fallen to below pre-closure levels at all sites, while the comparative stability of the transformed habitats was reflected by biomass-abundance distribution patterns that approximated pre-disturbance ratios. Despite initial generality, respective sites demonstrated distinct ecological responses that were related to the environmental characteristics of their transformed habitats. This simplistic analysis provides a sensitive and informative assessment of ecological conditions that highlights the impact to ecosystem process and ecological networks and has particular value in regions where detailed ecological knowledge precludes the application of traditional bioassessment methods.

Keywords: ABC curves, SADs, biodiversity, damming, tropical fish

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