Search results for: infection size
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1948

Search results for: infection size

1918 The Effect of Nonnormality on CB-SEM and PLS-SEM Path Estimates

Authors: Z. Jannoo, B. W. Yap, N. Auchoybur, M. A. Lazim

Abstract:

The two common approaches to Structural Equation Modeling (SEM) are the Covariance-Based SEM (CB-SEM) and Partial Least Squares SEM (PLS-SEM). There is much debate on the performance of CB-SEM and PLS-SEM for small sample size and when distributions are nonnormal. This study evaluates the performance of CB-SEM and PLS-SEM under normality and nonnormality conditions via a simulation. Monte Carlo Simulation in R programming language was employed to generate data based on the theoretical model with one endogenous and four exogenous variables. Each latent variable has three indicators. For normal distributions, CB-SEM estimates were found to be inaccurate for small sample size while PLS-SEM could produce the path estimates. Meanwhile, for a larger sample size, CB-SEM estimates have lower variability compared to PLS-SEM. Under nonnormality, CB-SEM path estimates were inaccurate for small sample size. However, CB-SEM estimates are more accurate than those of PLS-SEM for sample size of 50 and above. The PLS-SEM estimates are not accurate unless sample size is very large.  

Keywords: CB-SEM, Monte Carlo simulation, Normality conditions, Nonnormality, PLS-SEM.

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1917 Impact of Hepatitis C Virus Chronic Infection on Quality of Life in Egypt

Authors: Ammal M. Metwally, Ghada A. Abdel-Latif, Walaa A. Fouad, Thanaa M. Rabah, Amira Mohsen, Fatma A. Shaaban, Iman I. Salama

Abstract:

The study aimed at determining the impact of chronic hepatitis C virus (HCV) infection on patients’ Quality of Life (QoL), its relation to geographical characteristics of patients, awareness of the disease, treatment regimen, co-morbid psychiatric or other diseases. 457 patients were randomly selected from ten National Treatment Reference Centers of Ministry of Health hospitals from four community locations representing Egypt. Health related QoL assessment questionnaire with the 36-item Short Form used for assessment of the enrolled patients. The study showed no significant difference between HCV patients in different governorates as regards total QoL. Females, illiterate patients and those had bilharziasis, diabetes mellitus, hypertension or were depressed had significantly the lowest QoL score. HCV patients who knew the danger of the disease had significant lower mean score of physical and mental health components. Optimal care of overall well-being of HCV patients requires adequate knowledge of their neurological and psychological status. It is important to know how to cope with having a family member with hepatitis C and more importantly to know what should you say and what shouldn’t you say as a positive hopeful attitude is essential for combating HCV chronic infection.

Keywords: Hepatitis C virus chronic infection, physical health component and mental health component of QoL, total quality of life.

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1916 Stabilization of Angular-Shaped Riprap under Overtopping Flows

Authors: Dilavar Khan, Z. Ahmad

Abstract:

Riprap is mostly used to prevent erosion by flows down the steep slopes in river engineering. A total of 53 stability tests performed on angular riprap with a median stone size ranging from 15 to 278 mm and slope ranging from 1 to 40% are used in this study. The existing equations for the prediction of medium size of angular stones are checked for their accuracy using the available data. Predictions of median size using these equations are not satisfactory and results show deviation by more than ±20% from the observed values. A multivariable power regression analysis is performed to propose a new equation relating the median size with unit discharge, bed slope, riprap thickness and coefficient of uniformity. The proposed relationship satisfactorily predicts the median angular stone size with ±20% error. Further, the required size of the rounded stone is more than the angular stone for the same unit discharge and the ratio increases with unit discharge and also with embankment slope of the riprap.

Keywords: Angularity, Gradation, Riprap, Stabilization

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1915 The Influence of Clayey Pellet Size on Adsorption Efficiency of Metal Ions Removal from Waste Printing Developer

Authors: Kiurski S. Jelena, Ranogajec G. Jonjaua, Oros B. Ivana, Kecić S. Vesna

Abstract:

The adsorption efficiency of fired clayey pellets of 5 and 8 mm diameter size for Cu(II) and Zn(II) ion removal from a waste printing developer was studied. In order to investigate the influence of contact time, adsorbent mass and pellet size on the adsorption efficiency the batch mode was carried out. Faster uptake of copper ion was obtained with the fired clay pellets of 5 mm diameter size within 30 minutes. The pellets of 8 mm diameter size showed the higher equilibrium time (60 to 75 minutes) for copper and zinc ion. The results pointed out that adsorption efficiency increases with the increase of adsorbent mass. The maximal efficiency is different for Cu(II) and Zn(II) ion due to the pellet size. Therefore, the fired clay pellets of 5 mm diameter size present an effective adsorbent for Cu(II) ion removal (adsorption efficiency is 63.6%), whereas the fired clay pellets of 8 mm diameter size are the best alternative for Zn(II) ion removal (adsorption efficiency is 92.8%) from a waste printing developer.

Keywords: Adsorption efficiency, clayey pellet, metal ions, waste printing developer.

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1914 A Report on Occurrence and Parasite-Host of Ligula intestinalis in Sattarkhan Lake(East Azerbaijan-Iran)

Authors: Mahbobeh Hajirostamloo

Abstract:

Ligula intestinalis is a three-host life-cycle Pseudophyllidean Cestode which in its plerocercoid stage infests a range of fresh water species. The objective of the present study was the worm occurrence within planctonic copepods, fishes and piscivorous birds and examine of parasite-hosts samples in the Lake of Sattarkhan Dam (near the city of Ahar, East Azerbaijan, Iran). Fish sample were collected with fyke and gill nets and the abdominal cavity was examined for the presence of ligula. Zooplanktons were captured using a planktonic net and occurrence of parasitic larval form in the body cavity was determined. Piscivorous birds were selected by telescope, they hunted and dissected for presence of parasite eggs in their gut. Results indicated that prevalence of infection was 16% for cyclopid copepoda and majority of infected cyclopid were female Cyclops. Investigation of 310 fishes specimens were indicated to infection of five species of cyprinid fishes. In addition, results indicated to manipulation of six species of migratory aquatic and semi aquatic birds by ligula. Obtained results are in agreement by previous studies. Its definite in this study that all of fishes in Sattarkhan Lake capable to infection, its important for health because they capture by native people and it is documented that ligula can be introduce as a zoonose. It's seemed that to prevent from disperses of parasite and restricted of infection, biological elimination can be effective and it's necessary to inform native people about sanitation.

Keywords: Ligula intestinalis, parasite-host, Sattarkhan Lake, Iran.

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1913 An Adequate Choice of Initial Sample Size for Selection Approach

Authors: Mohammad H. Almomani, Rosmanjawati Abdul Rahman

Abstract:

In this paper, we consider the effect of the initial sample size on the performance of a sequential approach that used in selecting a good enough simulated system, when the number of alternatives is very large. We implement a sequential approach on M=M=1 queuing system under some parameter settings, with a different choice of the initial sample sizes to explore the impacts on the performance of this approach. The results show that the choice of the initial sample size does affect the performance of our selection approach.

Keywords: Ranking and Selection, Ordinal Optimization, Optimal Computing Budget Allocation, Subset Selection, Indifference-Zone, Initial Sample Size.

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1912 Negative RT-PCR in a Newborn Infected with Zika Virus: A Case Report

Authors: Vallejo Michael, Acuña Edgar, Roa Juan David, Peñuela Rosa, Parra Alejandra, Casallas Daniela, Rodriguez Sheyla

Abstract:

Congenital Zika Virus Syndrome is an entity composed by a variety of birth defects presented in newborns that have been exposed to the Zika Virus during pregnancy. The syndrome characteristic features are severe microcephaly, cerebral tissue abnormalities, ophthalmological abnormalities such as uveitis and chorioretinitis, arthrogryposis, clubfoot deformity and muscular tone abnormalities. The confirmatory test is the Reverse transcription polymerase chain reaction (RT-PCR) associated to the physical findings. Here we present the case of a newborn with microcephaly whose mother presented a confirmed Zika Virus infection during the third trimester of pregnancy, despite of the evident findings and the history of Zika infection the RT-PCR in amniotic and cerebrospinal fluid of the newborn was negative. RT-PCR has demonstrated a low sensibility in samples with low viral loads, reason why, we propose a clinical diagnosis in patients with clinical history of Zika Virus infection during pregnancy accompanied by evident clinical manifestations of the child.

Keywords: Zika Virus, polymerase chain reaction, microcephaly, amniotic fluid.

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1911 Effect of Particle Size on Alkali-Activation of Slag

Authors: E. Petrakis, V. Karmali, K. Komnitsas

Abstract:

In this study grinding experiments were performed in a laboratory ball mill using Polish ferronickel slag in order to study the effect of the particle size on alkali activation and the properties of the produced alkali activated materials (AAMs). In this regard, the particle size distribution and the specific surface area of the grinding products in relation to grinding time were assessed. The experimental results show that products with high compressive strength, e.g. higher than 60 MPa, can be produced when the slag median size decreased from 39.9 μm to 11.9 μm. Also, finer fractions are characterized by higher reactivity and result in the production of AAMs with lower porosity and better mechanical properties.

Keywords: Alkali activated materials, compressive strength, particle size distribution, slag.

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1910 Identification of COVID-SARS Variants Based on Lactate Test Results

Authors: Zoltan Horvath, Dora Nagy

Abstract:

In this research, it was examined whether individual COVID variants cause differences in the lactate curve of cyclists. After all, the virus variants attacked different organs in our body during the infections. During our tests, we used a traditional lactate step test, the results of which were compared with the values before the infection. In the tests, it has been proven that different virus variants show unique lactate curves. In this way, based on the lactate curve, it is possible to identify which variant caused the disease. Thanks to this, the return time has been shorten, because we can apply the best return protocol after infection to the competitors.

Keywords: SARS-CoV-2, lactate step test, virus mutation, lactate profile.

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1909 Preparation of ATO Conductive Particles with Narrow Size Distribution

Authors: Yueying Wu, Fengzhu Lv, Yihe Zhang, Zixian Xu

Abstract:

Antimosy-doped tin oxide (ATO) particles were prepared via chemical coprecipitation and reverse emulsion. The size and size distribution of ATO particles were obviously decreased via reverse microemulsion method. At the relatively high yield the ATO particles were nearly spherical in shape, meanwhile the crystalline structure and excellent conductivity were reserved, which could satisfy the requirement as composite fillers, such as dielectric filler of polyimide film.

Keywords: ATO particle, Conductivity, Distribution, Reverse emulsion

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1908 Modelling, Simulation and Validation of Plastic Zone Size during Deformation of Mild Steel

Authors: S. O. Adeosun, E. I. Akpan, S. A. Balogun, O. O. Taiwo

Abstract:

A model to predict the plastic zone size for material under plane stress condition has been developed and verified experimentally. The developed model is a function of crack size, crack angle and material property (dislocation density). Simulation and validation results show that the model developed show good agreement with experimental results. Samples of low carbon steel (0.035%C) with included surface crack angles of 45o, 50o, 60o, 70o and 90o and crack depths of 2mm and 4mm were subjected to low strain rate between 0.48 x 10-3 s-1 – 2.38 x 10-3 s-1. The mechanical properties studied were ductility, tensile strength, modulus of elasticity, yield strength, yield strain, stress at fracture and fracture toughness. The experimental study shows that strain rate has no appreciable effect on the size of plastic zone while crack depth and crack angle plays an imperative role in determining the size of the plastic zone of mild steel materials.

Keywords: Applied stress, crack angle, crack size, material property, plastic zone size, strain rate.

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1907 Identification of Binding Proteins That Interact with BVDV E2 Protein in Bovine Trophoblast Cell

Authors: Yan Ren, Fei Guo, Jun Qiao, Shengwei Hu, Hui Zhang, Yuanzhi Wang, Pengyan Wang, Jinliang Sheng, Xinli Gu, Xiaojun Liu, Chuangfu Chen

Abstract:

Bovine viral diarrhea virus (BVDV) can cause lifelong persistent infection. One reason for the phenomena is attributed to BVDV infection to placenta tissue. However the mechanisms that BVDV invades into placenta tissue remain unclear. To clarify the molecular mechanisms, we investigated the possible means that BVDV entered into bovine trophoblast cells (TPC). Yeast two-hybrid system was used to identify proteins extracted from TPC, which interact with BVDV envelope glycoprotein E2. A PGbkt7-E2 yeast expression vector and TPC cDNA library were constructed. Through two rounds of screening, three positive clones were identified. Sequencing analysis indicated that all the three positive clones encoded the same protein clathrin. Physical interaction between clathrin and BVDV E2 protein was further confirmed by coimmunoprecipitation experiments. This result suggested that the clathrin might play a critical role in the process of BVDV entry into placenta tissue and might be a novel antiviral target for preventing BVDV infection.

Keywords: Bovine viral diarrhea virus, clathrin, glycoprotein E2, yeast two-hybrid system.

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1906 Preparation of Size Controlled Silver on Carbon from E-waste by Chemical and Electro-Kinetic Processes

Authors: Mahmoud A. Rabah

Abstract:

Preparation of size controlled nano-particles of silver catalyst on carbon substrate from e-waste has been investigated. Chemical route was developed by extraction of the metals available in nitric acid followed by treatment with hydrofluoric acid. Silver metal particles deposited with an average size 4-10 nm. A stabilizer concentration of 10- 40 g/l was used. The average size of the prepared silver decreased with increase of the anode current density. Size uniformity of the silver nano-particles was improved distinctly at higher current density no more than 20mA... Grain size increased with EK time whereby aggregation of particles was observed after 6 h of reaction.. The chemical method involves adsorption of silver nitrate on the carbon substrate. Adsorbed silver ions were directly reduced to metal particles using hydrazine hydrate. Another alternative method is by treatment with ammonia followed by heating the carbon loaded-silver hydroxide at 980°C. The product was characterized with the help of XRD, XRF, ICP, SEM and TEM techniques.

Keywords: e-waste, silver catalyst, metals recovery, electrokinetic process.

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1905 Effect of Specimen Thickness on Probability Distribution of Grown Crack Size in Magnesium Alloys

Authors: Seon Soon Choi

Abstract:

The fatigue crack growth is stochastic because of the fatigue behavior having an uncertainty and a randomness. Therefore, it is necessary to determine the probability distribution of a grown crack size at a specific fatigue crack propagation life for maintenance of structure as well as reliability estimation. The essential purpose of this study is to present the good probability distribution fit for the grown crack size at a specified fatigue life in a rolled magnesium alloy under different specimen thickness conditions. Fatigue crack propagation experiments are carried out in laboratory air under three conditions of specimen thickness using AZ31 to investigate a stochastic crack growth behavior. The goodness-of-fit test for probability distribution of a grown crack size under different specimen thickness conditions is performed by Anderson-Darling test. The effect of a specimen thickness on variability of a grown crack size is also investigated.

Keywords: Crack size, Fatigue crack propagation, Magnesium alloys, Probability distribution, Specimen thickness.

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1904 Particle Size Effect on Shear Strength of Granular Materials in Direct Shear Test

Authors: R. Alias, A. Kasa, M. R. Taha

Abstract:

The effect of particle size on shear strength of granular materials are investigated using direct shear tests. Small direct shear test (60 mm by 60 mm by 24 mm deep) were conducted for particles passing the sieves with opening size of 2.36 mm. Meanwhile, particles passing the standard 20 mm sieves were tested using large direct shear test (300 mm by 300 mm by 200 mm deep). The large direct shear tests and the small direct shear tests carried out using the same shearing rate of 0.09 mm/min and similar normal stresses of 100, 200 and 300 kPa. The results show that the peak and residual shear strength increases as particle size increases.

Keywords: Particle size, shear strength, granular material, direct shear test.

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1903 Some Immunological Characteristics of Tick- Borne Encephalitis in Perm Region

Authors: Some Immunological Characteristics of Tick- Borne Encephalitis in Perm Region

Abstract:

It is shown that the relationship of tick-borne encephalitis virus with the human body comes in two ways, the development of acute infection with the outcome in convalescence and long stay by the virus in the body, its persistence in the nervous tissue with periodic reactivation and prolonged circulating immunoglobulin M. In spite of the fact that tick-borne encephalitis virus has a tropism for nerve tissue, involvement in the process of blood cells is an integral component of the infection. Comprehensive study of the relation of factors of innate and adaptive immunity in the tick-borne encephalitis providing insight into the features of chronic disease.

Keywords: Tick-borne encephalitis, phagocytic activity, a progressive.

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1902 An Optimal Algorithm for HTML Page Building Process

Authors: Maryam Jasim Abdullah, Bassim. H. Graimed, Jalal. S. Hameed

Abstract:

Demand over web services is in growing with increases number of Web users. Web service is applied by Web application. Web application size is affected by its user-s requirements and interests. Differential in requirements and interests lead to growing of Web application size. The efficient way to save store spaces for more data and information is achieved by implementing algorithms to compress the contents of Web application documents. This paper introduces an algorithm to reduce Web application size based on reduction of the contents of HTML files. It removes unimportant contents regardless of the HTML file size. The removing is not ignored any character that is predicted in the HTML building process.

Keywords: HTML code, HTML tag, WEB applications, Document compression, DOM tree.

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1901 Safe, Effective, and Cost-Efficient Air Cleaning for Populated Rooms and Entire Buildings Based on the Disinfecting Power of Vaporized Hypochlorous Acid

Authors: D. Boecker, R. Breves, F. Herth, Z. Zhang, C. Bulitta

Abstract:

Pathogen-carrying aerosol particles are recognized as important infection carriers like those in the current Corona pandemic. This infection route is often underestimated yet represents the infection route that has been least systematically countered to date. Particularly, the transmission indoors is of the highest concern but current indoor safety measures (e.g.: distancing, masks, filters) provide only limited protection. Inhalation of hypochlorous acid (HOCl) containing aerosols may become an alternate route to attack the incubating microbes in-situ and so potentially lead to a reduction of symptoms of already infected individuals. We investigated a facility-wide air-disinfection concept utilizing the potential of vaporized HOCl to become a disinfecting agent for populated indoor atmospheres. Aerosolized bacterial microbes were used as surrogates for a viral contamination, particularly the enveloped coronavirus. For the room air purification tests we aerosolized bacterial suspensions into lab chambers preloaded with vaporized HOCl solutions. Concentration of ‘free active chlorine’ in the test chamber atmosphere was determined with a special gas sensor system (Draeger AG, Lübeck, Germany) controlling the amount of vaporized HOCl via an aerosolis® device (oji Europe GmbH, Nauen, Germany). We could confirm the disinfecting power of HOCl in suspensions and determined the high efficacy of vaporized HOCl to disinfect atmospheres of populated indoor places at safe and non-irritant levels.

Keywords: Hypochlorous acid, HOCl, indoor air cleaning, infection control, microbial air burden, protective atmosphere.

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1900 Microalbuminuria in Human Immunodeficiency Virus Infection and Acquired Immunodeficiency Syndrome

Authors: Sharan Badiger, Prema T. Akkasaligar, Patil LS, Manish Patel, Biradar MS

Abstract:

Human immunodeficiency virus infection and acquired immunodeficiency syndrome is a global pandemic with cases reporting from virtually every country and continues to be a common infection in developing country like India. Microalbuminuria is a manifestation of human immunodeficiency virus associated nephropathy. Therefore, microalbuminuria may be an early marker of human immunodeficiency virus associated nephropathy, and screening for its presence may be beneficial. A strikingly high prevalence of microalbuminuria among human immunodeficiency virus infected patients has been described in various studies. Risk factors for clinically significant proteinuria include African - American race, higher human immunodeficiency virus ribonucleic acid level and lower CD4 lymphocyte count. The cardiovascular risk factors of increased systolic blood pressure and increase fasting blood sugar level are strongly associated with microalbuminuria in human immunodeficiency virus patient. These results suggest that microalbuminuria may be a sign of current endothelial dysfunction and micro-vascular disease and there is substantial risk of future cardiovascular disease events. Positive contributing factors include early kidney disease such as human immunodeficiency virus associated nephropathy, a marker of end organ damage related to co morbidities of diabetes or hypertension, or more diffuse endothelial cells dysfunction. Nevertheless after adjustment for non human immunodeficiency virus factors, human immunodeficiency virus itself is a major risk factor. The presence of human immunodeficiency virus infection is independent risk to develop microalbuminuria in human immunodeficiency virus patient. Cardiovascular risk factors appeared to be stronger predictors of microalbuminuria than markers of human immunodeficiency virus severity person with human immunodeficiency virus infection and microalbuminuria therefore appear to potentially bear the burden of two separate damage related to known vascular end organ damage related to know vascular risk factors, and human immunodeficiency virus specific processes such as the direct viral infection of kidney cells.The higher prevalence of microalbuminuria among the human immunodeficiency virus infected could be harbinger of future increased risks of both kidney and cardiovascular disease. Further study defining the prognostic significance of microalbuminuria among human immunodeficiency virus infected persons will be essential. Microalbuminuria seems to be a predictor of cardiovascular disease in diabetic and non diabetic subjects, hence it can also be used for early detection of micro vascular disease in human immunodeficiency virus positive patients, thus can help to diagnose the disease at the earliest.

Keywords: Acquired immunodeficiency syndrome, Human immunodeficiency virus, Microalbuminuria.

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1899 User’s Susceptibility Factors to Malware Attacks: A Systemic Literature Review

Authors: Awad A. Younis, Elise Stronberg, Shifa Noor

Abstract:

Users’ susceptibility to malware attacks have been noticed in the past few years. Investigating the factors that make a user vulnerable to those attacks is critical because they can be utilized to set up proactive strategies such as awareness and education to mitigate the impacts of those attacks. Demographic, behavioral, and cultural vulnerabilities are the main factors that make users susceptible to malware attacks. It is challenging, however, to draw more general conclusions based on those factors due to the varieties in the type of users and different types of malware. Therefore, we conducted a systematic literature review (SLR) of the existing research for user susceptibility factors to malware attacks. The results showed that all demographic factors are consistently associated with malware infection regardless of the users' type except for age and gender. Besides, the association of culture and personality factors with malware infection is consistent in most of the selected studies and for all types of users. Moreover, malware infection varies based on age, geographic location, and host types. We propose that future studies should carefully take into consideration the type of users because different users may be exposed to different threats or targeted based on their user domains’ characteristics. Additionally, as different types of malware use different tactics to trick users, taking the malware types into consideration is important.

Keywords: cybersecurity, malware, users, demographics, personality, culture, systematic literature review

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1898 Effect of Mesh Size on the Supersonic Viscous Flow Parameters around an Axisymmetric Blunt Body

Authors: Rabah Haoui

Abstract:

The aim of this work is to analyze a viscous flow around the axisymmetric blunt body taken into account the mesh size both in the free stream and into the boundary layer. The resolution of the Navier-Stokes equations is realized by using the finite volume method to determine the flow parameters and detached shock position. The numerical technique uses the Flux Vector Splitting method of Van Leer. Here, adequate time stepping parameter, CFL coefficient and mesh size level are selected to ensure numerical convergence. The effect of the mesh size is significant on the shear stress and velocity profile. The best solution is obtained with using a very fine grid. This study enabled us to confirm that the determination of boundary layer thickness can be obtained only if the size of the mesh is lower than a certain value limits given by our calculations.

Keywords: Supersonic flow, viscous flow, finite volume, blunt body.

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1897 A Prediction Method for Large-Size Event Occurrences in the Sandpile Model

Authors: S. Channgam, A. Sae-Tang, T. Termsaithong

Abstract:

In this research, the occurrences of large size events in various system sizes of the Bak-Tang-Wiesenfeld sandpile model are considered. The system sizes (square lattice) of model considered here are 25×25, 50×50, 75×75 and 100×100. The cross-correlation between the ratio of sites containing 3 grain time series and the large size event time series for these 4 system sizes are also analyzed. Moreover, a prediction method of the large-size event for the 50×50 system size is also introduced. Lastly, it can be shown that this prediction method provides a slightly higher efficiency than random predictions.

Keywords: Bak-Tang-Wiesenfeld sandpile model, avalanches, cross-correlation, prediction method.

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1896 Approximate Confidence Interval for Effect Size Base on Bootstrap Resampling Method

Authors: S. Phanyaem

Abstract:

This paper presents the confidence intervals for the effect size base on bootstrap resampling method. The meta-analytic confidence interval for effect size is proposed that are easy to compute. A Monte Carlo simulation study was conducted to compare the performance of the proposed confidence intervals with the existing confidence intervals. The best confidence interval method will have a coverage probability close to 0.95. Simulation results have shown that our proposed confidence intervals perform well in terms of coverage probability and expected length.

Keywords: Effect size, confidence interval, Bootstrap Method.

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1895 Analyzing the Factors Influencing Exclusive Breastfeeding Using the Generalized Poisson Regression Model

Authors: Cheika Jahangeer, Naushad Mamode Khan, Maleika Heenaye-Mamode Khan

Abstract:

Exclusive breastfeeding is the feeding of a baby on no other milk apart from breast milk. Exclusive breastfeeding during the first 6 months of life is of fundamental importance because it supports optimal growth and development during infancy and reduces the risk of obliterating diseases and problems. Moreover, in developed countries, exclusive breastfeeding has decreased the incidence and/or severity of diarrhea, lower respiratory infection and urinary tract infection. In this paper, we study the factors that influence exclusive breastfeeding and use the Generalized Poisson regression model to analyze the practices of exclusive breastfeeding in Mauritius. We develop two sets of quasi-likelihood equations (QLE)to estimate the parameters.

Keywords: Exclusive breastfeeding, Regression model, Quasilikelihood.

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1894 Computational Model for Prediction of Soil-Gas Radon-222 Concentration in Soil-Depths and Soil Grain Size Particles

Authors: I. M. Yusuff, O. M. Oni, A. A. Aremu

Abstract:

Percentage of soil-gas radon-222 concentration (222Rn) from soil-depths contributing to outdoor radon atmospheric level depends largely on some physical parameters of the soil. To determine its dependency in soil-depths, survey tests were carried out on soil depths and grain size particles using in-situ measurement method of soil-gas radon-222 concentration at different soil depths. The measurements were carried out with an electronic active radon detector (RAD-7) manufactured by Durridge Company USA. Radon-222 concentrations (222Rn) in soil-gas were measured at four different soil depths of 20, 40, 60 and 100 cm in five feasible locations. At each soil depth, soil samples were collected for grain size particle analysis using soil grasp sampler. The result showed that highest value of radon-222 concentration (24,680 ± 1960 Bqm-3) was measured at 100 cm depth with utmost grain size particle of 17.64% while the lowest concentration (7370 ± 1139 Bqm-3) was measured at 100 cm depth with least grain size particle of 10.75% respectively. A computational model was derived using SPSS regression package. This model could be a yardstick for prediction on soil gas radon concentration reference to soil grain size particle at different soil-depths.

Keywords: Concentration, radon, porosity, diffusion, colorectal, emanation, yardstick.

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1893 Analyzing Data on Breastfeeding Using Dispersed Statistical Models

Authors: Naushad Mamode Khan, Cheika Jahangeer, Maleika Heenaye-Mamode Khan

Abstract:

Exclusive breastfeeding is the feeding of a baby on no other milk apart from breast milk. Exclusive breastfeeding during the first 6 months of life is very important as it supports optimal growth and development during infancy and reduces the risk of obliterating diseases and problems. Moreover, it helps to reduce the incidence and/or severity of diarrhea, lower respiratory infection and urinary tract infection. In this paper, we make a survey of the factors that influence exclusive breastfeeding and use two dispersed statistical models to analyze data. The models are the Generalized Poisson regression model and the Com-Poisson regression models.

Keywords: Exclusive breastfeeding, regression model, generalized poisson, com-poisson.

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1892 The Effect of Granule Size on the Digestibility of Wheat Starch Using an in vitro Model

Authors: Mee-Lin Lim Chai Teo, Darryl M. Small

Abstract:

Wheat has a bimodal starch granule population and the dependency of the rate of enzymatic hydrolysis on particle size has been investigated. Ungelatinised wheaten starch granules were separated into two populations by sedimentation and decantation. Particle size was analysed by laser diffraction and morphological characteristics were viewed using SEM. The sedimentation technique though lengthy, gave satisfactory separation of the granules. Samples (<10μm, >10μm and original) were digested with a-amylase using a dialysis model. Granules of <10μm showed significantly higher rate of reducing sugar release than those >10μm (p<0.05). In contrast, the rate was not significantly different between the original sample and granules >10μm. Moreover, the digestion rate was dependent on particle size whereby smaller granules produced higher rate of release. The methodology and results reported here can be used as a basis for further evaluations designed to delay the release of glucose during the digestion of native starches.

Keywords: in vitro Digestion, a-amylase, wheat starch, granule size.

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1891 Designing Pictogram for Food Portion Size

Authors: Y.C. Liu, S.J. Lu, Y.C. Weng, H. Su

Abstract:

The objective of this paper is to investigate a new approach based on the idea of pictograms for food portion size. This approach adopts the model of the United States Pharmacopeia- Drug Information (USP-DI). The representation of each food portion size composed of three parts: frame, the connotation of dietary portion sizes and layout. To investigate users- comprehension based on this approach, two experiments were conducted, included 122 Taiwanese people, 60 male and 62 female with ages between 16 and 64 (divided into age groups of 16-30, 31-45 and 46-64). In Experiment 1, the mean correcting rate of the understanding level of food items is 48.54% (S.D.= 95.08) and the mean response time 2.89sec (S.D.=2.14). The difference on the correct rates for different age groups is significant (P*=0.00<0.05). In Experiment 2, the correcting rate of selecting the right life-size measurement aid is 65.02% (S.D.=21.31). The result showed the potential of the approach for certain food potion sizes. Issues raised for discussions including comprehension on numerous food varieties in an open environment, selection of photograph or drawing, reasons of different correcting rates for the measurement aid. This research also could be used for those interested in systematic and pictorial representation of dietary portion size information.

Keywords: Comprehension, Food Portion Size, Model of DietaryInformation, Pictogram Design, USP-DI.

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1890 Determination of Strain Rate Sensitivity (SRS) for Grain Size Variants on Nanocrystalline Material Produced by ARB and ECAP

Authors: P. B. Sob, A. A. Alugongo, T. B. Tengen

Abstract:

Mechanical behavior of 6082T6 aluminum is investigated at different temperatures. The strain rate sensitivity is investigated at different temperatures on the grain size variants. The sensitivity of the measured grain size variants on 3-D grain is discussed. It is shown that the strain rate sensitivities are negative for the grain size variants during the deformation of nanostructured materials. It is also observed that the strain rate sensitivities vary in different ways with the equivalent radius, semi minor axis radius, semi major axis radius and major axis radius. From the obtained results, it is shown that the variation of strain rate sensitivity with temperature suggests that the strain rate sensitivity at the low and the high temperature ends of the 6082T6 aluminum range is different. The obtained results revealed transition at different temperature from negative strain rate sensitivity as temperature increased on the grain size variants.

Keywords: Nanostructured materials, grain size variants, temperature, yield stress, strain rate sensitivity.

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1889 Human Immunodeficiency Virus Infection and Cardiac Autonomic Neuropathy

Authors: Sharan Badiger, Prema T. Akkasaligar, Deepak Kadeli

Abstract:

Human Immunodeficiency Virus is known to affect almost all organ systems in the body. In addition to central nervous system it also affects the autonomic nervous system. Autonomic nervous dysfunction has been known to severely affect the quality of life in human immunodeficiency virus positive patients. It is known to have caused fatal consequences in late stages of the disease in patients who go in for invasive diagnostic or therapeutic procedures. The aim of this review is to determine the incidence, clinical significance and frequency of cardiac autonomic neuropathy in patients human immunodeficiency virus infection.

Keywords: Autonomic nervous system, autonomic nervous dysfunction, cardiac autonomic dysfunction, human immunodeficiency virus.

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