Search results for: random effect

Authors: Manfred F. Maute, Olga Naumenko, Raymond T. Kong

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Using data from a nationally representative financial panel of Canadian households, this study develops a psychographic segmentation of the customers of a value-expressive credit card service and tests for effects on relational response differences. The variety of segments elicited by agglomerative and k means clustering and the familiar profiles of individual clusters suggest that the face validity of the psychographic segmentation was quite high. Segmentation had a significant effect on customer satisfaction and relationship depth. However, when socio-demographic characteristics like household size and income were accounted for in the psychographic segmentation, the effect on relational response differences was magnified threefold. Implications for the segmentation of financial services markets are considered.

Keywords: customer satisfaction, financial services, psychographics, response differences, segmentation

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Authors: Jubee Varghese, Pouria Hafiz

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Increased use of lightweight concrete in the construction industry is mainly due to its reduction in the weight of the structural elements, which in turn reduces the cost of production, transportation, and the overall project cost. However, the structural application of these lightweight concrete structures is limited due to its reduced density. Hence, further investigations are in progress to study the effect of fiber inclusion in improving the mechanical properties of lightweight concrete. Incorporating structural steel fibers, in general, enhances the performance of concrete and increases its durability by minimizing its potential to cracking and providing crack arresting mechanism. In this research, Geometric and Materially Non-linear Analysis (GMNA) was conducted for Finite Element Modelling using a software known as ABAQUS, to investigate the structural behavior of lightweight concrete with and without the addition of steel fibers and shear reinforcement. 21 finite element models of beams were created to study the effect of steel fibers based on three main parameters; fiber volume fraction (Vf = 0, 0.5 and 0.75%), shear span to depth ratio (a/d of 2, 3 and 4) and ratio of area of shear stirrups to spacing (As/s of 0.7, 1 and 1.6). The models created were validated with the previous experiment conducted by H.K. Kang et al. in 2011. It was seen that the lightweight fiber reinforcement can replace the use of fiber reinforced normal weight concrete as structural elements. The effect of an increase in steel fiber volume fraction is dominant for beams with higher shear span to depth ratio than for lower ratios. The effect of stirrups in the presence of fibers was very negligible; however; it provided extra confinement to the cracks by reducing the crack propagation and extra shear resistance than when compared to beams with no stirrups.

Keywords: ABAQUS, beams, fiber-reinforced concrete, finite element, light weight, shear span-depth ratio, steel fibers, steel-fiber volume fraction

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Authors: Ajay Likhite, Prashant Parhad, D. R. Peshwe, S. U. Pathak

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Chromium bearing Austempered Ductile Iron (ADI) has been recently in the news for its improved wear performance over the ADI. The work presented below was taken up to study the effect of different austenitisation temperatures on the microstructure and wear performance of the Carbidic Austempered Ductile Iron (CADI). In this investigation Cr bearing ductile iron was subjected to austempering treatment to obtain an ausferritic microstructure. Two different austenitisation temperatures were selected whereas, the austempering temperature and time was kept unchanged. Microstructure and wear performance of this alloy, austenitized at two different temperatures was studied.

Keywords: austempered ductile iron, carbidic austempered ductile iron, austenitization temperature, wear behavior

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Authors: Gul Muhammad, Amanullah Marri, Asif Abbas

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Thermal treatment changes the physical and mechanical properties of clayey soils. Thermally treated soils have been used since ancient times for making trails for access and bricks for residence. In this study, it has been focused to observe and analyze the effect of baking (burning) temperature on the mechanical properties of clayey soils usually used for the construction of adobe houses in the rural areas of many of the developing countries. In the first stage of experimental work, a series of tests on clayey soil moulds (100 mm height and 50 mm diameter in size) added different percentages of lime and wheat straw (typically 2%, 4%, 6%, 8%, and 10%) were conducted. In the second stage; samples were made of clayey soils and were subjected to six level of temperatures i.e., 25, 100, 200, 300, 400, and 500⁰C. In the third stage, the moulds of clayey soil were submerged in water prior to testing in order to investigate the flood resilience of the moulds prepared with and without the addition of lime and wheat straw. The experimental results suggest that samples with 6% of lime content and on 2% of wheat straw contents have shown the maximum value of compressive strength. The effect of baking temperature on the clayey soils has shown that maximum UCS is obtained at 200⁰C. The results also suggest reinforcement with 2% wheat straw, give 70.8% increase in the compressive strength compared to soil only, whereas the flooding resilience can be better resist by adding 6% lime and 2% wheat straw.

Keywords: baked temperature, submersion, lime, uniaxial, wheat straw

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Authors: Yonas Shuke Kitawa

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Background: Although malaria incidence has substantially fallen sharply over the past few years, the rate of decline varies by district, time, and malaria type. Despite this turn-down, malaria remains a major public health threat in various districts of Ethiopia. Consequently, the present study is aimed at developing a predictive model that helps to identify the spatio-temporal variation in malaria risk by multiple plasmodium species. Methods: We propose a multivariate spatio-temporal Bayesian model to obtain a more coherent picture of the temporally varying spatial variation in disease risk. The spatial autocorrelation in such a data set is typically modeled by a set of random effects that assign a conditional autoregressive prior distribution. However, the autocorrelation considered in such cases depends on a binary neighborhood matrix specified through the border-sharing rule. Over here, we propose a graph-based optimization algorithm for estimating the neighborhood matrix that merely represents the spatial correlation by exploring the areal units as the vertices of a graph and the neighbor relations as the series of edges. Furthermore, we used aggregated malaria count in southern Ethiopia from August 2013 to May 2019. Results: We recognized that precipitation, temperature, and humidity are positively associated with the malaria threat in the area. On the other hand, enhanced vegetation index, nighttime light (NTL), and distance from coastal areas are negatively associated. Moreover, nonlinear relationships were observed between malaria incidence and precipitation, temperature, and NTL. Additionally, lagged effects of temperature and humidity have a significant effect on malaria risk by either species. More elevated risk of P. falciparum was observed following the rainy season, and unstable transmission of P. vivax was observed in the area. Finally, P. vivax risks are less sensitive to environmental factors than those of P. falciparum. Conclusion: The improved inference was gained by employing the proposed approach in comparison to the commonly used border-sharing rule. Additionally, different covariates are identified, including delayed effects, and elevated risks of either of the cases were observed in districts found in the central and western regions. As malaria transmission operates in a spatially continuous manner, a spatially continuous model should be employed when it is computationally feasible.

Keywords: disease mapping, MSTCAR, graph-based optimization algorithm, P. falciparum, P. vivax, waiting matrix

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Authors: Nail Nazarov, Vladimir Zobov, Alexandra Vyshtakalyuk, Vyacheslav Semenov, Irina Galyametdinova, Vladimir Reznik

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There have been studied effects of xymedon and six new pyrimidine derivatives, that are close and distant analogs of xymedon, on rats' working capacity in the test 'swimming to failure'. It has been shown that a single administration of the studied compounds did not have a statistically significant effect in the test. In the conditions of multiple intraperitoneal administration of the studied pyrimidine derivatives, the compound L-ascorbate, 1-(2-hydroxyethyl)-4.6-dimethyl-1.2-dihydropyrimidine-2-one had the lowest toxicity and the most pronounced actoprotective effect. Introduction in the dose of 20 mg/kg caused a statistically significant increase 440 % in the duration of swimming of rats on the 14th day of the experiment compared with the control group. Multiple administration of the compound in the conditions of physical load did not affect leucopoiesis but stimulates erythropoiesis resulting in an increase in the number of erythrocytes and a hemoglobin level. The substance introduction under mixed exhausting loads prevented such changes of blood biochemical parameters as reduction of glucose, increased of urea and lactic acid levels, what indicates improvement in the animals' tolerability of loads and an anti-catabolic effect of the compound. Absence of hepato and cardiotoxic effects of the substance has been shown. This work was performed with the financial support of Russian Science Foundation (grant № 14-50-00014).

Keywords: actoprotectors, physical working capacity, pyrimidine derivatives, xymedon

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Authors: Elizabeth Spink

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Providing safe and affordable drinking water to low-income households in developing countries remains a challenge. Policy goals of increasing household piped-water access and cost recovery for utility providers are often at odds. Nonpayment of utility bills is frequently cited as a constraint to improving the quality of utility service. However, nonpayment is widely tolerated, and households often accumulate significant debt to the utility provider. This study examines the effect of enforcement of water bill payment through supply disconnections in Livingstone, Zambia. This research uses a dynamic model of household monthly payments and accumulation of arrears, which determine the probability of disconnection, and simulates the effect of exogenous changes in enforcement levels. This model is empirically tested using an event-study framework of exogenous increases in enforcement capacity that occur during administrative rezoning events, which reduce the number of households that one enforcement agent is responsible for. The results show that households are five percentage points more likely to make a payment in the months following a rezoning event, but disconnections for low-income households increase as well, resulting in little change in revenue collected by the water utility. The results suggest that high enforcement of water bill payments toward credit-constrained households may be ineffective and lead to reduced piped-water access.

Keywords: enforcement, nonpayment, piped-water access, water utilities

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Authors: Ming-Tzu Tsai, Jui-Ting Hsu, Chia-Chieh Lin, Feng-Tsai Chiang, Cheng-Chin Huang

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Far infrared (FIR), an invisible and short electromagnetic waves ranges from 6-14 μm also defines as the “growth ray.” Although the mechanism of FIR is still unknown, most data have suggested that FIR could accelerate the skin microcirculation by elevating the blood flow and nitric-oxide (NO) synthesis. In this present work, the effect of FIR irradiation and endothelial cell growth supplement (ECGS) on human umbilical vascular endothelial cells (HUVECs) was evaluated. To understand whether the cell viability and NO production of HUVECs affected by NO, cells with/without ECGS were treated in the presence or absence of L-NAME, an eNOS inhibitor. For FIR exposure, FIR-emitted ceramic powders consisted of a variety of well-mixed metal oxides were developed. The results showed that L-NAME did had a strong effect on the inhibition of NO production, especially in the ECGS-treated group. However, the cell viability of each group was rarely affected in the presence of L-NAME. Cells with the incubation of ECGS showed much higher cell viability compared to the control. Moreover, NO production of HUVECs exposed to FIR irradiation was significantly inhibited in the presence of L-NAME. It suggested that NO could play a role modulating the downstream signals of HUVECs during FIR exposure.

Keywords: far-infrared irradiation (FIR), nitric oxide (NO), endothelial nitric oxide synthase (eNOS), endothelial cell growth supplement (ECGS)

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Authors: Krisada Lekdee, Sunee Sammatat, Nittaya Boonsit

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This paper proposes a GLMM with spatial and temporal effects for malaria data in Thailand. A Bayesian method is used for parameter estimation via Gibbs sampling MCMC. A conditional autoregressive (CAR) model is assumed to present the spatial effects. The temporal correlation is presented through the covariance matrix of the random effects. The malaria quarterly data have been extracted from the Bureau of Epidemiology, Ministry of Public Health of Thailand. The factors considered are rainfall and temperature. The result shows that rainfall and temperature are positively related to the malaria morbidity rate. The posterior means of the estimated morbidity rates are used to construct the malaria maps. The top 5 highest morbidity rates (per 100,000 population) are in Trat (Q3, 111.70), Chiang Mai (Q3, 104.70), Narathiwat (Q4, 97.69), Chiang Mai (Q2, 88.51), and Chanthaburi (Q3, 86.82). According to the DIC criterion, the proposed model has a better performance than the GLMM with spatial effects but without temporal terms.

Keywords: Bayesian method, generalized linear mixed model (GLMM), malaria, spatial effects, temporal correlation

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Authors: Olusegun Adeleke Adenuga

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The study examined effect of fishbone creative thinking strategy on problem-solving skills of public teachers in Ogun state, Nigeria. A 2x2x2 factorial design was employed for the study which consisted of 80 participants made up of 40 male and 40 female public teachers randomly selected among public teaching personnel from the two local government area headquarters (Ijebu-ode and Ijebu-Igbo) within Ogun East Senatorial District. Each treatment group received 45minutes instructions and training per week for 8weeks. Data was collected from participants with the use of standardized instrument tagged ‘Problem Solving Inventory’ (PSI) developed by the researchers prior to the training to form a pre-test and immediately after eight weeks of training to form a post-test. One hypothesis was tested; the data obtained was analyzed using Analysis of Covariance (ANCOVA) tested at significance level of 0.05. The result of the data analysis shows that there was a significant effect of the fishbone creative thinking technique on the participants (F (2,99) = 12.410; p <.05). Based on the findings, it is therefore recommended that the report of this study be used to effect organizational change and development of teaching service in Nigeria through teachers’ retraining and capacity building.

Keywords: fishbone, creative thinking strategy, and problem-solving skills, public teachers

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Authors: Zhou BingHai, Fradet Victor

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Lean philosophy follows the simple principle of “creating more value with fewer resources”. In accordance with this policy, material handling can be managed by the mean of Kanban which by triggering every feeding tour only when needed regulates the flow of material in one of the most efficient way. This paper focuses on Kanban Supermarket’s parameters and their optimization on a purely cost-based point of view. Number and size of forklifts, as well as size of the containers they carry, will be variables of the cost function which includes handling costs, inventory costs but also shortage costs. With an innovative computational approach encoded into industrial engineering software Tecnomatix and reproducing real-life conditions, a fictive assembly line is established and produces a random list of orders. Multi-scenarios are then run to study the impact of each change of parameter and the variation of costs it implies. Lastly, best-case scenarios financially speaking are selected.

Keywords: Kanban, supermarket, parts-feeding policies, multi-scenario simulation, assembly line

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Authors: Kyung Min Kwom, Young Joo Lee

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Purpose: Up to 90% of pancreatic cancer patient suffer from neuropathic pain. In palliative care setting, pain control in a pancreatic cancer patient is one of the major goals. Ketamine is a NMDA receptor antagonist effective in neuropathic pain. Also, there have been studies about opioid sparing effect of ketamine. This study was held in palliative care unit among pancreatic cancer patients to find out the factors related to ketamine use and the opioid sparing effect. Methods: Medical records of pancreatic cancer patients admitted to St. Mary’s hospital palliative care unit from 2013.1 to 2014.12 were reviewed. Patients were divided into two categories according to ketamine use. Also, opioid use before and after ketamine use was compared in ketamine group. Results: Compared to non ketamine use group, patients in ketamine group required a higher dose of opioid. Total opioid dose, daily opioid dose, number of daily rescue medication, daily average rescue dose were statistically significantly higher in ketamine group. Opioid requirement was increased after ketamine administration. Conclusion: In this study, ketamine group required more opioid. Ketamine is frequently considered in patients with severe pain, requiring high amount of opioid. Also, ketamine did not have an opioid sparing effect. Future studies about palliative use of ketamine in a larger number of patients are required.

Keywords: ketamine, opioid sparing, palliative care, pancreatic cancer

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Authors: Nanteza Rachel

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Background: Worldwide, there were 36.7 million people living with Human Immunodeficiency Virus (HIV) in 2015, up from 35 million at the end of 2013. Wakiso district is one of the hotspots for the Human Immunodeficiency Virus (HIV)/ Acquired Immune Deficiency Syndrome (AIDS) infection in Uganda, with the prevalence of 8.1 %. Herbal medicine has gained popularity among Human Immunodeficiency Virus (HIV)/ Acquired Immune Deficiency Syndrome (AIDS) patients as adjuvant therapy to reduce the adverse effects of ART. Regardless of the subsidized and physical availability of the Anti-Retroviral Therapy (ART), majority of Africans living with Human Immunodeficiency Virus (HIV)/ Acquired Immune Deficiency Syndrome (AIDS) resort to adding to their ART traditional medicine. Result found out from a pilot observation made by the PI that indicate 13 out of 30 People Living with AIDS(PLWA) who are attending Human Immunodeficiency Virus (HIV) clinics in Wakiso district reported to be using herbal preparations despite the fact that they were taking Anti Retro Viral (ARVs) this prompted this study to be done. Purpose of the study: To determine the prevalence and factors associated with concurrent use of herbal medicine and anti-retroviral therapy among HIV/AIDS patients attending selected HIV clinics in Wakiso district. Methodology: This was a cross sectional study with both quantitative data collection (use of a questionnaire) and qualitative data collection (key informants’ interviews). A mixed method of sampling was used, that is, purposive and random sampling. Purposive sampling was based on the location in the district and used to select 7 health facilities basing on the 7 health sub districts from Wakiso. Simple random sampling was used to select one HIV clinic from each of the 7 health sub districts. Furthermore, the study units were enrolled in to the study as they entered into the HIV clinics, and 105 respondents were interviewed. Both manual and computer packages (SPSS) were used to analyze the data Results: The prevalence of concurrent use of herbal medicine and ART was 38 (36.2%). Commonly HIV symptom treated with herbs was fever 27(71.1%), diarrhea 3(7.9%) and cough 2(5.3%). Commonly used herbs for fever (Omululuza (Vernonica amydalina), Ekigagi (Aloe sp), Nalongo (Justicia betonica Linn) while for diarrhea was Ntwatwa. The side effects also included; too much pain, itchy pain of HIV, aneamia,felt sick, loss/gain appetite, joint pain and bad dreams. Herbs used to sooth the side effects were; for aneamia was avocado leaves Parea Americana mill The significant factors associated with concurrent use of herbal medicine were being familiar with herbs and conventional medicine for management HIV symptoms being expensive. The other significant factor was exhibiting hostility to patients by health personnel providing HIV care. Conclusion: Herbal medicine is widely used by clients in HIV/AIDS care. Patients being familiar with herbs and conventional medicine being expensive were associated with concurrent use of herbal medicine and ART. The exhibition of hostility to the HIV/AIDS patients by the health care providers was also associated with concurrent use of herbal medicine and ART among HIV/AIDS patients.

Keywords: HIV patients, herbal medicine, antiretroviral therapy, factors associated

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Authors: Muhammad Rafiq Shahid, Ali Hassan, Umm-e- Rubab, Muhammad Nadeem

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Insecticidal property of plant extracts was assessed toward dusky bug of cotton. Plant extracts consisted of bari pata (Ziziphus jajuba), Ak (Calotropis gigantean), Tobacco (Nicotiana tabacum), Bakine (Melia azedarach),Kanar (Nerium oleander),Kurtuma (Mitragyna speciosa) and one Control was also included with distilled water treatment. Forced feeding experiment was used to determine the antibiotic effect of bug plant extracts on dusky bug whereas Multi-choice experiment to determine the antixenosis/ repellent property of botanicals. It is evident from the results that mortality and antibiosis percentage of dusky bug due to the use of botanicals ranged from 15-95% and 20-87.3% respectively that was maximum in tobacoo extract followed by bakain and kurtama, minimum was on Ak, kanair and bakain extract. Non preference ranged from 14.28 to 85.7 where maximum non preference of dusky bug was found on bakain and kurtama followed by ak and kanair however minimum was on Bari pata extract. It was further found that local plant extract possessed insecticidal property toward dusky bug as well as also possesses repellency effect toward dusky bug, thus should be included in integrated pest management program of cotton in order to minimize the ill effects of pesticides it is compulsory to adopt eco-friendly methods of insect pest management.

Keywords: botanical extract, insecticidal and repellency activity, Gossypium hirsutum, oxycarenus laetus

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Authors: Imad H. Hameed, Mohammad A. Jebor, Ammera J. Omer

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The aim of this research is to study the mitochonderial coding region by using the Sanger sequencing technique and establish the degree of variation characteristic of a fragment. FTA® Technology (FTA™ paper DNA extraction) utilized to extract DNA. Portion of coding region encompassing positions 11719 –12384 amplified in accordance with the Anderson reference sequence. PCR products purified by EZ-10 spin column then sequenced and Detected by using the ABI 3730xL DNA Analyzer. Five new polymorphic positions 11741, 11756, 11878, 11887 and 12133 are described may be suitable sources for identification purpose in future. The calculated value D= 0.95 and RMP=0.048 of the genetic diversity should be understood as high in the context of coding function of the analysed DNA fragment. The relatively high gene diversity and a relatively low random match probability were observed in Iraq population. The obtained data can be used to identify the variable nucleotide positions characterized by frequent occurrence which is most promising for various identifications.

Keywords: coding region, Iraq, mitochondrial DNA, polymorphic positions, sanger technique

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Authors: Ashish Kumar, Kaptan Singh, Amit Saxena

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Today, it is believed that crimes have the greatest impact on a person's ability to progress financially and personally. Identifying places where individuals shouldn't go is crucial for preventing crimes and is one of the key considerations. As society and technologies have advanced significantly, so have crimes and the harm they wreak. When there is a concentration of people in one place and changes happen quickly, it is even harder to prevent. Because of this, many crime prevention strategies have been embraced as a component of the development of smart cities in numerous cities. However, crimes can occur anywhere; all that is required is to identify the pattern of their occurrences, which will help to lower the crime rate. In this paper, an analysis related to crime has been done; information related to crimes is collected from all over India that can be accessed from anywhere. The purpose of this paper is to investigate the relationship between several factors and India's crime rate. The review has covered information related to every state of India and their associated regions of the period going in between 2001- 2014. However various classes of violations have a marginally unique scope over the years.

Keywords: K-nearest neighbor, random forest, decision tree, pre-processing

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Authors: N. Choobkar, M. Rezaeimanesh, A. M. Emami Rad, M. Ghaeni, H. Norouzi, S. Pahlavani, M. S. Tamasoki, E. Nezafatian

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Antibiotics are used to increase the immune and wound healing in many animals . But due to the residual effects of a drug , researchers sought to replace them with natural materials such as Plant extracts. Falcaria vulgaris is the most attractive sources of the new drugs. Falcaria vulgaris (locally named Ghazzyaghi/Poghazeh) is a member of Umbelliferae family which grows near farmlands and is consumed as a vegetable in some regions of Iran. In the West of the country, in the wound healing and irregularities in the digestive system is also used. There were no scientific reports available in literature in support of the traditional claims of F. vulgaris in fish. The present study is therefore an attempt to assess the efficacy of this indigenous herb for its healing effect in common carp (Cyprinus carpio). Falcaria vulgaris at concentrations of 0, 2 and 10 % with Lophag foods used on wound healing of common carp and immune response, and weight grow and survival during periods of 21 days with feeding 2 times per day on the basis of body weight. The results showed that, compared with the control group, using of concentration 10 % F. vulgaris have significant effect on wound healing and stimulates the immune system by increasing white blood cells (WBC) and weight grow and survival of carp. The herb can used in wound healing, increased resistance to disease and weight grow in fish and the beneficial effects of this combination goes back to man.

Keywords: common carp, falcaria vulgaris, immune response, wound healing

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Authors: A. Satty, H. Mwambi

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Much clinical trials data-based research are characterized by the unavoidable problem of dropout as a result of missing or erroneous values. This paper aims to review some of the various techniques to address the dropout problems in longitudinal clinical trials. The fundamental concepts of the patterns and mechanisms of dropout are discussed. This study presents five general techniques for handling dropout: (1) Deletion methods; (2) Imputation-based methods; (3) Data augmentation methods; (4) Likelihood-based methods; and (5) MNAR-based methods. Under each technique, several methods that are commonly used to deal with dropout are presented, including a review of the existing literature in which we examine the effectiveness of these methods in the analysis of incomplete data. Two application examples are presented to study the potential strengths or weaknesses of some of the methods under certain dropout mechanisms as well as to assess the sensitivity of the modelling assumptions.

Keywords: incomplete longitudinal clinical trials, missing at random (MAR), imputation, weighting methods, sensitivity analysis

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Authors: Gülşen Akın Evingür, Önder Pekcan

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The fractal analysis is a bridge between the microstructure and macroscopic properties of gels. Fractal structure is usually provided to define the complexity of crosslinked molecules. The complexity in gel systems is described by the fractal dimension (Df). In this study, polyacrylamide- graphene oxide (GO) composite gels were prepared by free radical crosslinking copolymerization. The fractal analysis of polyacrylamide- graphene oxide (GO) composite gels were analyzed in various GO contents during gelation and were investigated by using Fluorescence Technique. The analysis was applied to estimate Df s of the composite gels. Fractal dimension of the polymer composite gels were estimated based on the power law exponent values using scaling models. In addition, here we aimed to present the geometrical distribution of GO during gelation. And we observed that as gelation proceeded GO plates first organized themselves into 3D percolation cluster with Df=2.52, then goes to diffusion limited clusters with Df =1.4 and then lines up to Von Koch curve with random interval with Df=1.14. Here, our goal is to try to interpret the low conductivity and/or broad forbidden gap of GO doped PAAm gels, by the distribution of GO in the final form of the produced gel.

Keywords: composite gels, fluorescence, fractal, scaling

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Authors: Konstantza Tonova, Ivan Svinyarov, Milen G. Bogdanov

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Ionic liquids consisting of pairs of imidazolium or phosphonium cation and chloride or saccharinate anion were synthesized and compared with respect to their extraction efficiency towards the fermentative L-lactic acid. The acid partitioning in the equilibrated biphasic systems of ionic liquid and water was quantified through the extraction degree and the partition coefficient. The water transfer from the aqueous into the ionic liquid-rich phase was also always followed. The effect of pH, which determines the state of lactic acid in the aqueous source was studied. The effect of other salting-out substances that modify the ionic liquid/water equilibrium was also investigated in view to reveal the best liquid-liquid system with respect to low toxicity, high extraction and back extraction efficiencies and performance simplicity.

Keywords: ionic liquids, biphasic system, extraction, lactic acid

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Authors: M. Meenasaranya, S. Saravanan

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Nonlinear stability analysis is carried out to determine the effect of surface temperature modulation in an infinite horizontal porous layer heated from below. The layer is saturated by an electrically conducting, viscous, incompressible and Newtonian fluid. The Brinkman model is used for momentum equation, and the Boussinesq approximation is invoked. The system is assumed to be bounded by rigid boundaries. The energy theory is implemented to find the global exponential stability region of the considered system. The results are analysed for arbitrary values of modulation frequency and amplitude. The existence of subcritical instability region is confirmed by comparing the obtained result with the known linear result. The vertical magnetic field is found to stabilize the system.

Keywords: Brinkman model, energy method, magnetic field, surface temperature modulation

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Authors: Ayman Abd-Elhamed, Sayed Mahmoud

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The present research work investigates the seismic response of reinforced concrete (RC) frame building considering the effect of modeling masonry infill (MI) walls. The seismic behavior of a residential 6-storey RC frame building, considering and ignoring the effect of masonry, is numerically investigated using response spectrum (RS) analysis. The considered herein building is designed as a moment resisting frame (MRF) system following the Egyptian code (EC) requirements. Two developed models in terms of bare frame and infill walls frame are used in the study. Equivalent diagonal strut methodology is used to represent the behavior of infill walls, whilst the well-known software package ETABS is used for implementing all frame models and performing the analysis. The results of the numerical simulations such as base shear, displacements, and internal forces for the bare frame as well as the infill wall frame are presented in a comparative way. The results of the study indicate that the interaction between infill walls and frames significantly change the responses of buildings during earthquakes compared to the results of bare frame building model. Specifically, the seismic analysis of RC bare frame structure leads to underestimation of base shear and consequently damage or even collapse of buildings may occur under strong shaking. On the other hand, considering infill walls significantly decrease the peak floor displacements and drifts in both X and Y-directions.

Keywords: masonry infill, bare frame, response spectrum, seismic response

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Authors: Serge Provost, Yishan Zang

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Copulas are currently utilized in finance, reliability theory, machine learning, signal processing, geodesy, hydrology and biostatistics, among several other fields of scientific investigation. It follows from Sklar's theorem that the joint distribution function of a multidimensional random vector can be expressed in terms of its associated copula and marginals. Since marginal distributions can easily be determined by making use of a variety of techniques, we address the problem of securing the distribution of the copula. This will be done by using several approaches. For example, we will obtain bivariate least-squares approximations of the empirical copulas, modify the kernel density estimation technique and propose a criterion for selecting appropriate bandwidths, differentiate linearized empirical copulas, secure Bernstein polynomial approximations of suitable degrees, and apply a corollary to Sklar's result. Illustrative examples involving actual observations will be presented. The proposed methodologies will as well be applied to a sample generated from a known copula distribution in order to validate their effectiveness.

Keywords: copulas, Bernstein polynomial approximation, least-squares polynomial approximation, kernel density estimation, density approximation

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Authors: E. H. Walsh, J. McMahon, M. P. Herring

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Post-primary school-based suicide prevention (PSSP) is a valuable avenue to reduce suicidal behaviours in adolescents. The aims of this meta-analysis and meta-regression were 1) to quantify the effect of PSSP interventions on adolescent suicide ideation (SI) and suicide attempts (SA), and 2) to explore how intervention effects may vary based on important contextual and intervention factors. This study provides further support to the benefits of PSSP by demonstrating lower suicide outcomes in over 30,000 adolescents following PSSP and mental health interventions and tentatively suggests that intervention effectiveness may potentially vary based on intervention factors. The protocol for this study is registered on PROSPERO (ID=CRD42020168883). Population, intervention, comparison, outcomes, and study design (PICOs) defined eligible studies as cluster randomised studies (n=12) containing PSSP and measuring suicide outcomes. Aggregate electronic database EBSCO host, Web of Science, and Cochrane Central Register of Controlled Trials databases were searched. Cochrane bias tools for cluster randomised studies demonstrated that half of the studies were rated as low risk of bias. The Egger’s Regression Test adapted for multi-level modelling indicated that publication bias was not an issue (all ps > .05). Crude and corresponding adjusted pooled log odds ratios (OR) were computed using the Metafor package in R, yielding 12 SA and 19 SI effects. Multi-level random-effects models accounting for dependencies of effects from the same study revealed that in crude models, compared to controls, interventions were significantly associated with 13% (OR=0.87, 95% confidence interval (CI), [0.78,0.96], Q18 =15.41, p=0.63) and 34% (OR=0.66, 95%CI [0.47,0.91], Q10=16.31, p=0.13) lower odds of SI and SA, respectively. Adjusted models showed similar odds reductions of 15% (OR=0.85, 95%CI[0.75,0.95], Q18=10.04, p=0.93) and 28% (OR=0.72, 95%CI[0.59,0.87], Q10=10.46, p=0.49) for SI and SA, respectively. Within-cluster heterogeneity ranged from no heterogeneity to low heterogeneity for SA across crude and adjusted models (0-9%). No heterogeneity was identified for SI across crude and adjusted models (0%). Pre-specified univariate moderator analyses were not significant for SA (all ps < 0.05). Variations in average pooled SA odds reductions across categories of various intervention characteristics were observed (all ps < 0.05), which preliminarily suggests that the effectiveness of interventions may potentially vary across intervention factors. These findings have practical implications for researchers, clinicians, educators, and decision-makers. Further investigation of important logical, theoretical, and empirical moderators on PSSP intervention effectiveness is recommended to establish how and when PSSP interventions best reduce adolescent suicidal behaviour.

Keywords: adolescents, contextual factors, post-primary school-based suicide prevention, suicide ideation, suicide attempts

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Authors: Nwamaka Patricia Ibeme, Musa Zakari

Abstract:

E-learning is made more effective because; it is enable student to students to easily interact, share, and collaborate across time and space with the help of e-governance platform. Zoom and the Microsoft classroom team can invite students from all around the world to join a conversation on a certain subject simultaneously. E-governance may be able to work on problem solving skills, as well as brainstorming and developing ideas. As a result of the shared experiences and knowledge, students are able to express themselves and reflect on their own learning." For students, e-governance facilities provide greater opportunity for students to build critical (higher order) thinking abilities through constructive learning methods. Students' critical thinking abilities may improve with more time spent in an online classroom. Students' inventiveness can be enhanced through the use of computer-based instruction. Discover multimedia tools and produce products in the styles that are easily available through games, Compact Disks, and television. The use of e-learning has increased both teaching and learning quality by combining student autonomy, capacity, and creativity over time in developed countries." Teachers are catalysts for the integration of technology through Information and Communication Technology, and e-learning supports teaching by simplifying access to course content." Creating an Information and Communication Technology class will be much easier if educational institutions provide teachers with the assistance, equipment, and resources they need. The study adopted survey research design. The populations of the study are Students and staff. The study adopted a simple random sampling technique to select a representative population. Both primary and secondary method of data collection was used to obtain the data. A chi-square statistical technique was used to analyze. Finding from the study revealed that e-learning has increase accesses to universities educational by public servants in Nigeria. Public servants in Nigeria have utilized e-learning and Online Distance Learning (ODL) programme to into various degree programmes. Finding also shows that E-learning plays an important role in teaching because it is oriented toward the use of information and communication technologies that have become a part of the everyday life and day-to-day business. E-learning contributes to traditional teaching methods and provides many advantages to society and citizens. The study recommends that the e-learning tools and internet facilities should be upgrade to foster any network challenges in the online facilitation and lecture delivery system.

Keywords: E-governance, E-learning, online distance learning, university education public servants, Nigeria

Procedia PDF Downloads 53

Authors: Nadia A. Mohamed, Mehrevan M. Abdel-Moniem

Abstract:

Zingiber officinale (ginger) has been cultivated for medicinal purposes due to their various proprieties both in vitro and in vivo, so we designed to evaluate the ginger’s potential effect on nephrin m RNA expression in cisplatin-induced nephrotoxic rats. Method: Forty male albino rats were divided into group I was injected (IP) with one ml saline, group II(cisplatin) injected (IP) with a single dose of 12 mg/kg cisplatin, group III (ginger) received (PO) 310 mg/kg for 30 successive days, and group IV(cisplatin and ginger) rats received ginger extract (310 mg/kg) daily for 20 successive days (PO), and then on day 20 of ginger extract administration each rat was injected(IP) with a single dose of 12 mg/kg cisplatin. The blood was sampled to assess urea, creatinine (SC), while the levels of malondialdehyde (MDA), nitric oxide (NO) and paraoxonase (PON1) were measured in kidney tissue homogenate. Expression of urinary nephrin gene (nephrin mRNA) was detected using qRT-PCR. Results: Treatment with ginger significantly decreased the levels of kidney function parameters as well as MDA and NO elevated by cisplatin injection, while PON1 was significantly reduced in the cisplatin group. However, the protection of male rats with ginger significantly increased the levels of nephrin gene expression and PON1 compared with the cisplatin-treated group. Our results generated a proposal on the ameliorating effect of ginger on nephrin mRNA gene expression reduction in cisplatin-induced nephrotoxicity.

Keywords: nephrin mRNA, ginger, cisplatin, nephrotoxicity

Procedia PDF Downloads 133

Authors: Fawehinmi Olabisi Alaba, O. R. Adeniyi

Abstract:

Farming households faces lots of disaster which contribute to endemic poverty. Anticipated increases in extreme weather events will exacerbate this. Primary data was administered to farming household using multi-stage random sampling technique. The result of the analysis shows that majority of the respondents (69.9%) are male, have mean household size, years of formal education and age of 5±1.14, 6±3.41, and 51.06±10.43 respectively. The major (48.9%) type of disaster experienced is flooding. Major coping mechanism adopted is sourcing for support from family and friends. Age, education, experience, access to extension agent, and mitigation control method contribute significantly to vulnerability to disaster. The major adaptation method (62.3%) is construction of drainage. The study revealed that the coping mechanisms employed may become less effective as increasingly fragile livelihood systems struggle to withstand disaster shocks. Thus there is need for training of the farmers on measures to adapt to mitigate the shock from disasters.

Keywords: adaptation, disasters, flooding, vulnerability

Procedia PDF Downloads 245

Authors: Arun Kumar Singh, Rupesh M. Das, Shailendra Saini

Abstract:

The effect of solar cycle and seasons on the total electron content has been investigated over high latitude region during 24th solar cycle (2010-2014). The total electron content data has been observed with the help of Global Ionospheric Scintillation and TEC monitoring (GISTM) system installed at Indian permanent scientific 'Maitri station' [70˚46’00”S 11˚43’56” E]. The dependence of TEC over a solar cycle has been examined by the performing linear regression analysis between the vertical total electron content (VTEC) and daily total sunspot numbers (SSN). It has been found that the season and level of geomagnetic activity has a considerable effect on the VTEC. It is observed that the VTEC and SSN follow better agreement during summer seasons as compared to winter and equinox seasons and extraordinary agreement during minimum phase (during the year 2010) of the solar cycle. There is a significant correlation between VTEC and SSN during quiet days of the years as compared to overall days of the years (2010-2014). Further, saturation effect has been observed during maximum phase (during the year 2014) of the 24th solar cycle. It is also found that Ap index and SSN has a linear correlation (R=0.37) and the most of the geomagnetic activity occurs during the declining phase of the solar cycle.

Keywords: high latitude ionosphere, sunspot number, correlation, vertical total electron content

Procedia PDF Downloads 176

Authors: Shirin Shafaei, James R. Bolton, Mohamed Gamal El Din

Abstract:

Ultraviolet (UV) disinfection causes damage to the DNA or RNA of microorganisms, but many microorganisms can repair this damage after exposure to near-UV or visible wavelengths (310–480 nm) by a mechanism called photoreactivation. Photoreactivation is gaining more attention because it can reduce the efficiency of UV disinfection of wastewater several hours after treatment. The focus of many photoreactivation research activities on the single species has caused a considerable lack in knowledge about complex natural communities of microorganisms and their response to UV treatment. In this research, photoreactivation experiments were carried out on the influent of the UV disinfection unit at a municipal wastewater treatment plant (WWTP) in Edmonton, Alberta after exposure to a Medium-Pressure (MP) UV lamp system to evaluate the effect of environmental factors on photoreactivation of microorganisms in the actual municipal wastewater. The effect of reactivation fluence, temperature, and river water on photoreactivation of total coliforms was examined under indoor conditions. The results showed that higher effective reactivation fluence values (up to 20 J/cm²) and higher temperatures (up to 25 °C) increased the photoreactivation of total coliforms. However, increasing the percentage of river in the mixtures of the effluent and river water decreased the photoreactivation of the mixtures. The results of this research can help the municipal wastewater treatment industry to examine the environmental effects of discharging their effluents into receiving waters.

Keywords: photoreactivation, reactivation fluence, river water, temperature, ultraviolet disinfection, wastewater effluent

Procedia PDF Downloads 292

Authors: Muhammad Azeem Qureshi, Hammad Tahir, Fawwad Mahmood Butt

Abstract:

Purpose: This study examines empirically the effect of brand satisfaction, brand trust and brand experience on brand loyalty which can be helpful to retain and increase customer base and satisfying customer needs as well. Methodology: Data has been collected on convenient sampling method and cause and effect among variables has been measured by applying regression analysis technique. Findings: Finding of this study have supported the proposed hypotheses and results show that brand loyalty is significantly explained by brand satisfaction, brand trust and brand experience. Practical Implications: The outcome of this study provides a useful framework and importance of brand loyalty culture in Pakistan. Marketers can be benefited trough the findings of this study.

Keywords: brand experience, brand satisfaction, brand trust, brand loyalty, hair-care products

Procedia PDF Downloads 308