Search results for: Gas Chromatography- Mass Spectrometry (GC-MS)
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1185

Search results for: Gas Chromatography- Mass Spectrometry (GC-MS)

495 The Effects of Different Amounts of Additional Moisture on the Physical Properties of Cow Pea (Vigna unguiculata (L.) Walp.) Extrudates

Authors: L. Strauta, S. Muižniece-Brasava

Abstract:

Even though legumes possess high nutritional value and have a rather high protein content for plant origin products, they are underutilized mostly due to their lengthy cooking time. To increase the presence of legume-based products in human diet, new extruded products were made of cow peas (Vigna unguiculata (L.) Walp.). But as it is known, adding different moisture content to flour before extrusion can change the physical properties of the extruded product. Experiments were carried out to estimate the optimal moisture content for cow pea extrusion. After extrusion, the pH level had dropped from 6.7 to 6.5 and the lowest hardness rate was observed in the samples with additional 9 g 100g-1 of moisture - 28±4N, but the volume mass of the samples with additional 9 g100g-1 of water was 263±3 g L-1; all samples were approximately 7±1mm long.

Keywords: Cow pea, extrusion-cooking, moisture, size.

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494 Relationship between Gender, BMI, and Lifestyle with Bone Mineral Density of Adolescent in Urban Areas

Authors: Ari Istiany

Abstract:

The purpose of this study was to analyze relationship between gender, BMI, and lifestyle with bone mineral density (BMD) of adolescent in urban areas . The place of this study in Jakarta State University, Indonesia. The number of samples involved as many as 200 people, consisting of 100 men and 100 women. BMD was measured using Quantitative Ultrasound Bone Densitometry. While the questionnaire used to collect data on age, gender, and lifestyle (calcium intake, smoking habits, alcohol consumption, tea, coffee, sports, and sun exposure). Mean age of men and women, respectively as much as 20.7 ± 2.18 years and 21 ± 1.61 years. Mean BMD values of men was 1.084 g/cm ² ± 0.11 while women was 0.976 g/cm ² ± 0.10. Men and women with normal BMD respectively as much as 46.7% and 16.7%. Men and women affected by osteopenia respectively as much as 50% and 80%. Men and women affected by osteoporosis respectively as much as 3.3% and 3.3%. Mean BMI of men and women, respectively as much as 21.4 ± 2.07 kg/m2 and 20.9 ± 2.06 kg/m2. Mean lifestyle score of men and women , respectively as much as 71.9 ± 5.84 and 70.1 ± 5.67 (maximum score 100). Based on Spearman and Pearson Correlation test, there were relationship significantly between gender and lifestyle with BMD.

Keywords: Adolescents, Body Mass Index (BMI), Bone Mineral Density (BMD), gender, and lifestyle.

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493 Data-organization Before Learning Multi-Entity Bayesian Networks Structure

Authors: H. Bouhamed, A. Rebai, T. Lecroq, M. Jaoua

Abstract:

The objective of our work is to develop a new approach for discovering knowledge from a large mass of data, the result of applying this approach will be an expert system that will serve as diagnostic tools of a phenomenon related to a huge information system. We first recall the general problem of learning Bayesian network structure from data and suggest a solution for optimizing the complexity by using organizational and optimization methods of data. Afterward we proposed a new heuristic of learning a Multi-Entities Bayesian Networks structures. We have applied our approach to biological facts concerning hereditary complex illnesses where the literatures in biology identify the responsible variables for those diseases. Finally we conclude on the limits arched by this work.

Keywords: Data-organization, data-optimization, automatic knowledge discovery, Multi-Entities Bayesian networks, score merging.

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492 An Unstructured Finite-volume Technique for Shallow-water Flows with Wetting and Drying Fronts

Authors: Rajendra K. Ray, Kim Dan Nguyen

Abstract:

An unstructured finite volume numerical model is presented here for simulating shallow-water flows with wetting and drying fronts. The model is based on the Green-s theorem in combination with Chorin-s projection method. A 2nd-order upwind scheme coupled with a Least Square technique is used to handle convection terms. An Wetting and drying treatment is used in the present model to ensures the total mass conservation. To test it-s capacity and reliability, the present model is used to solve the Parabolic Bowl problem. We compare our numerical solutions with the corresponding analytical and existing standard numerical results. Excellent agreements are found in all the cases.

Keywords: Finite volume method, Projection method, Shallow water, Unstructured grid, wetting/drying fronts.

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491 EHD Effect on the Dynamic Characteristics of a Journal Bearing Lubricated with Couple Stress Fluids

Authors: B. Chetti, W. A. Crosby

Abstract:

This paper presents a numerical analysis for the dynamic performance of a finite journal bearing lubricated with couple stress fluid taking into account the effect of the deformation of the bearing liner. The modified Reynolds equation has been solved by using finite difference technique. The dynamic characteristics in terms of stiffness coefficients, damping coefficients, critical mass and whirl ratio are evaluated for different values of eccentricity ratio and elastic coefficient for a journal bearing lubricated with a couple stress fluids and a Newtonian fluid. The results show that the dynamic characteristics of journal bearings lubricated with couple stress fluids are improved compared to journal bearings lubricated with Newtonian fluids.

Keywords: Circular bearing, elastohydrodynamic, stability, couple stress.

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490 Density Wave Instability of Supercritical Kerosene in Active Cooling Channels of Scramjets

Authors: N. Wang, Y. Pan, J. Zhou, J. Lei, X. Z. Yang

Abstract:

Experimental investigations were made on the instability of supercritical kerosene flowing in active cooling channels. Two approaches were used to control the pressure in the channel. One is the back-pressure valve while the other is the venturi. In both conditions, a kind of low-frequency oscillation of pressure and temperature is observed. And the oscillation periods are calculated. By comparison with the flow time, it is concluded that the instability occurred in active cooling channels is probably one kind of density wave instability. And its period has no relationship with the cooling channel geometry, nor the pressure, but only depends on the flow time of kerosene in active cooling channels. When the mass flow rate, density and pressure drop couple with each other, the density wave instability will appear.

Keywords: scramjets, active cooling, instability, density wave

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489 Analysis of OPG Gene Polymorphism T245G (rs3134069) in Slovak Postmenopausal Women

Authors: I. Boroňová, J. Bernasovská, J. Kľoc, Z. Tomková, E. Petrejčíková, S. Mačeková, J. Poráčová, M. M. Blaščáková

Abstract:

Osteoporosis is a common multifactorial disease with a strong genetic component characterized by reduced bone mass and increased risk of fractures. Genetic factors play an important role in the pathogenesis of osteoporosis. The aim of our study was to identify the genotype and allele distribution of T245G polymorphism in OPG gene in Slovak postmenopausal women. A total of 200 unrelated Slovak postmenopausal women with diagnosed osteoporosis and 200 normal controls were genotyped for T245G (rs3134069) polymorphism of OPG gene. Genotyping was performed using the Custom Taqman®SNP Genotyping assays. Genotypes and alleles frequencies showed no significant differences (p=0.5551; p=0.6022). The results of the present study confirm the importance of T245G polymorphism in OPG gene in the pathogenesis of osteoporosis.

Keywords: OPG gene, osteoporosis, Real-time PCR, T245G polymorphism.

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488 Mechanical and Hydric Properties of High- Performance Concrete Containing Natural Zeolites

Authors: E. Vejmelková, M. Ondráček, R. Černý

Abstract:

Mechanical and water transport properties of high performance concrete (HPC) containing natural zeolite as partial replacement of Portland cement are studied. Experimental results show that in the investigated mixes the use of natural zeolite leads to an increase of porosity, decrease of compressive strength and increase of moisture diffusivity and water vapor diffusion coefficient, as compared with the reference HPC. However, for the replacement level up to 20% of the mass of Portland cement the concretes still maintain their high performance character and exhibit acceptable water transport properties. Therefore, natural zeolite can be considered an environmental friendly binder with a potential to replace a part of Portland cement in concrete in building industry.

Keywords: Natural zeolites, high-performance concrete; hydric properties, mechanical properties

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487 Effect of Robot Configuration Parameters, Masses and Friction on Painlevé Paradox for a Sliding Two-Link (P-R) Robot

Authors: Hassan M. Alkomy, Hesham A. Elkaranshawy, Ahmed S. Ashour, Khaled T. Mohamed

Abstract:

For a rigid body sliding on a rough surface, a range of uncertainty or non-uniqueness of solution could be found, which is termed: Painlevé paradox. Painlevé paradox is the reason of a wide range of bouncing motion, observed during sliding of robotic manipulators on rough surfaces. In this research work, the existence of the paradox zone during the sliding motion of a two-link (P-R) robotic manipulator with a unilateral constraint is investigated. Parametric study is performed to investigate the effect of friction, link-length ratio, total height and link-mass ratio on the paradox zone.

Keywords: Dynamical system, friction, multibody system, Painlevé paradox, robotic systems, sliding robots, unilateral constraint.

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486 Influence of Surface Area on Dissolution of Additively Manufactured Polyvinyl Alcohol Tablets

Authors: Seyedebrahim Afkhami, Meisam Abdi, Reza Baserinia

Abstract:

Additive manufacturing is revolutionizing production in different industries, including pharmaceuticals. This case study explores the influence of surface area on the dissolution of additively manufactured polyvinyl alcohol parts as a polymer candidate. Specimens of different geometries and constant mass were fabricated using a Fused Deposition Modeling (FDM) 3D printer. The dissolution behavior of these samples was compared with respect to their surface area. Improved and accelerated dissolution was observed for samples with a larger surface area. This study highlights the capabilities of additive manufacturing to produce samples of complex geometries that cannot be manufactured otherwise to control the dissolution behavior for pharmaceutical and biopharmaceutical applications.

Keywords: Additive manufacturing, polymer dissolution, fused deposition modelling, geometry optimization.

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485 Analytical Study on Threats to Wetland Ecosystems and their Solutions in the Framework of the Ramsar Convention

Authors: Ehsan Daryadel, Farhad Talaei

Abstract:

Wetlands are one of the most important ecosystems on Earth. Nevertheless, various challenges threaten these ecosystems and disrupt their ecological character. Among these, the effects of human-based threats are more devastating. Following mass degradation of wetlands during 1970s, the Ramsar Convention on Wetlands (Ramsar, Iran, 1971) was concluded to conserve wetlands of international importance and prevent destruction and degradation of such ecosystems through wise use of wetlands as a mean to achieve sustainable development in all over the world. Therefore, in this paper, efforts have been made to analyze threats to wetlands and then investigate solutions in the framework of the Ramsar Convention. Finally, in order to operate these mechanisms, this study concludes that all states should in turn make their best effort to improve and restore global wetlands through preservation of environmental standards and close contribution and also through taking joint measures with other states effectively.

Keywords: Ramsar Convention, Threats, Wetland Ecosystems, Wise Use.

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484 A Frequency Dependence of the Phase Field Model in Laminar Boundary Layer with Periodic Perturbations

Authors: Yasuo Obikane

Abstract:

The frequency dependence of the phase field model(PFM) is studied. A simple PFM is proposed, and is tested in a laminar boundary layer. The Blasius-s laminar boundary layer solution on a flat plate is used for the flow pattern, and several frequencies are imposed on the PFM, and the decay times of the interfaces are obtained. The computations were conducted for three cases: 1) no-flow, and 2) a half ball on the laminar boundary layer, 3) a line of mass sources in the laminar boundary layer. The computations show the decay time becomes shorter as the frequency goes larger, and also show that it is sensitive to both background disturbances and surface tension parameters. It is concluded that the proposed simple PFM can describe the properties of decay process, and could give the fundamentals for the decay of the interface in turbulent flows.

Keywords: Phase field model, two phase flows, Laminarboundary Layer

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483 Target Trajectory Design of Parametrically Excited Inverted Pendulum for Efficient Bipedal Walking

Authors: Toyoyuki Honjo, Takeshi Hayashi, Akinori Nagano, Zhi-Wei Luo

Abstract:

For stable bipedal gait generation on the level floor, efficient restoring of mechanical energy lost by heel collision at the ground is necessary. Parametric excitation principle is one of the solutions. We dealt with the robot-s total center of mass as an inverted pendulum to consider the total dynamics of the robot. Parametrically excited walking requires the use of continuous target trajectory that is close to discontinuous optimal trajectory. In this paper, we proposed the new target trajectory based on a position in the walking direction. We surveyed relations between walking performance and the parameters that form the target trajectory via numerical simulations. As a result, it was found that our target trajectory has the similar characteristics of a parametrically excited inverted pendulum.

Keywords: Dynamic Bipedal Walking, Parametric Excitation, Target Trajectory Design.

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482 Design and Analysis of a Solar Refrigeration System with a Rotating Generator

Authors: K. Bouhadef, S. Chikh, A. Boumedien, A. Benabdesselam

Abstract:

A solar refrigeration system based on the adsorptiondesorption phenomena is designed and analyzed. An annular tubular generator filled with silica gel adsorbent and with a perforated inner cylinder is integrated within a flat solar collector. The working fluid in the refrigeration cycle is water. The thermodynamic analysis and because of the temperature level that could be attained with a flat solar collector it is required that the system operates under vacuum conditions. In order to enhance the performance of the system and to get uniform temperature in the silica gel and higher desorbed mass, an apparatus for rotation of the generator is incorporated in the system. Testing is carried out and measurements are taken on the designed installation. The effect of rotation is checked on the temperature distribution and on the performance of this machine and compared to the flat solar collector with fixed generator.

Keywords: Refrigeration cycle, solar energy, rotating collector, adsorption, silica gel.

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481 Influence of Gas-Liquid Separator Design on Performance of Airlift Bioreactors

Authors: Mateus N. Esperança, Marcel O. Cerri, Alberto C. Badino

Abstract:

The performance of airlift bioreactors are closely related with their geometry, especially the gas-liquid separator design. In this study, the influence of the gas-liquid separator geometry on oxygen transfer and gas hold-up was evaluated in 10-L concentric-tube airlift bioreactor operating with distilled water and xanthan gum solution. The specific airflow rate (ɸAIR) exhibited the higher effect on the oxygen transfer coefficient (kLa) for both fluids. While the gas-liquid separator openness angle (α) and liquid volume fraction on the gas-liquid separator (VGLS) have presented opposite effects on oxygen mass transfer, they affected negatively the global gas hold-up of distilled water system. The best degassing zone geometry corresponded to a 90° openness angle with 10% of the liquid on it.

Keywords: Airlift bioreactor, gas holdup, gas-liquid separator, oxygen transfer.

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480 The Effect of X-Ray on Plasma and Erythrocyte Concentration of Zn and Cu in Radiology Staff of Tehran Oil Hospital

Authors: L. Nekoozad, M. Salehi Barough, B. Salmasian

Abstract:

Introduction: Some parameters should be considered to investigate the chronic effects of radiation absorption in radiation workers. Trace elements are parameters which small changes in them can cause significant effects on live systems. The role of trace element concentration in human health is significant. These elements play an important role in the developing and functioning of the immune system, cellular respiration, and oxidation processes. Considering the importance and necessity of this issue and few studies, measurements of concentration changes of these elements due to the absorbed dose are important. Purpose: This study aimed to determine the biological effects of occupational dose absorption on plasma and erythrocyte concentration of Zn and Cu in the radiology staff of Tehran Oil Hospital. Material and methods: In this analytical-comparative study, 72 people have entered. 36 people (18 males and 18 females) were selected as radiology staff in the diagnostic and therapeutic departments of Tehran Oil Hospital. And 36 people (18 males and 18 females) were selected as general section staff in the same hospital as a control group. Radiology and control groups’ age and sex were matched. 10 ml of venous blood was taken from all people.  An atomic absorption spectrometer was used to obtain zinc and copper plasma concentrations. Levine test was used to compare these results validity. Results: The mean concentrations of copper and zinc were measured as 0.951 and 0.754 mg/L in the plasma phase and 3.2  and 0.401 mg/L in the RBC phase for the radiology group.  Copper and zinc average concentrations, respectively 0.976 and 0.813 mg/L in the plasma phase and 2.906 and 0.476 mg/L in the RBC phase, were measured for the control group. These elements Concentrations in the plasma phase were significantly different from that of the control group, but the concentrations in the red blood cell phase did not show a significant difference compared to the control group. In comparison, a separate comparison between men and women in the experimental and control groups showed a significant difference in the values of the elements mentioned. With a significant increase in samples, a better justification than the available statistical results can be extracted. Conclusions: Within this study results, chronic occupational probabilistic absorption destructive effects (even within the permitted range) on blood trace element concentration have been confirmed.

Keywords: Chronic absorption, atomic absorption spectrometry, radiology staff, trace element concentration.

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479 Prediction Heating Values of Lignocellulosics from Biomass Characteristics

Authors: Kaltima Phichai, Pornchanoke Pragrobpondee, Thaweesak Khumpart, Samorn Hirunpraditkoon

Abstract:

The paper provides biomasses characteristics by proximate analysis (volatile matter, fixed carbon and ash) and ultimate analysis (carbon, hydrogen, nitrogen and oxygen) for the prediction of the heating value equations. The heating value estimation of various biomasses can be used as an energy evaluation. Thirteen types of biomass were studied. Proximate analysis was investigated by mass loss method and infrared moisture analyzer. Ultimate analysis was analyzed by CHNO analyzer. The heating values varied from 15 to 22.4MJ kg-1. Correlations of the calculated heating value with proximate and ultimate analyses were undertaken using multiple regression analysis and summarized into three and two equations, respectively. Correlations based on proximate analysis illustrated that deviation of calculated heating values from experimental heating values was higher than the correlations based on ultimate analysis.

Keywords: Heating value equation, Proximate analysis, Ultimate analysis.

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478 An Approach Based on Statistics and Multi-Resolution Representation to Classify Mammograms

Authors: Nebi Gedik

Abstract:

One of the significant and continual public health problems in the world is breast cancer. Early detection is very important to fight the disease, and mammography has been one of the most common and reliable methods to detect the disease in the early stages. However, it is a difficult task, and computer-aided diagnosis (CAD) systems are needed to assist radiologists in providing both accurate and uniform evaluation for mass in mammograms. In this study, a multiresolution statistical method to classify mammograms as normal and abnormal in digitized mammograms is used to construct a CAD system. The mammogram images are represented by wave atom transform, and this representation is made by certain groups of coefficients, independently. The CAD system is designed by calculating some statistical features using each group of coefficients. The classification is performed by using support vector machine (SVM).

Keywords: Wave atom transform, statistical features, multi-resolution representation, mammogram.

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477 A Numerical Model Simulation for an Updraft Gasifier Using High Temperature Steam

Authors: T. M. Ismail, M. Abd El-Salam

Abstract:

A mathematical model study was carried out to investigate gasification of biomass fuels using high temperature air and steam as a gasifying agent using high-temperature air up to 1000°C. In this study, a 2D computational fluid dynamics model was developed to study the gasification process in an updraft gasifier, considering drying, pyrolysis, combustion, and gasification reactions. The gas and solid phases were resolved using a Euler−Euler multiphase approach, with exchange terms for the momentum, mass, and energy. The standard k−ε turbulence model was used in the gas phase, and the particle phase was modeled using the kinetic theory of granular flow. The results show that the present model giving a promise way in its capability and sensitivity for the parameter affects that influence the gasification process.

Keywords: Computational fluid dynamics, gasification, biomass fuel, fixed bed gasifier

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476 Changes of Power-Velocity Relationship in Female Volleyball Players during an Annual Training Cycle

Authors: K. Busko

Abstract:

The aim of the study was to follow changes of powervelocity relationship in female volleyball players during an annual training cycle. The study was conducted on eleven female volleyball players: age 21.6±1.7 years, body height 177.9±4.7 cm, body mass 71.3±6.6 kg and training experience 8.6±3.3 years. Power–velocity relationship was determined from five maximal 10-second cycloergometer efforts with external loads equal: 2.5, 5.0, 7.5, 10.0 and 12.5% of body weight (BW) before (I) and after (II) the preparatory period, after the first (III) and second (IV) competitive season. The maximal power output increased from 9.30±0.85 W•kg–1 (I) to 9.50±0.96 W•kg–1 (II), 9.77±0.96 W•kg–1 (III) and 9.95±1.13 W•kg–1 (IV, p<0,05). The power output at the load of 2.5, 5.0, 7.5, 10.0% BW were statistically significant increased after the first and second competitive season. Power output at load of 12.5% BW was insignificant increased.

Keywords: Female, Force-velocity relationship, Power output, Volleyball

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475 Biodiesel Production from High Iodine Number Candlenut Oil

Authors: Hary Sulistyo, Suprihastuti S. Rahayu, Gatot Winoto, I M. Suardjaja

Abstract:

Transesterification of candlenut (aleurites moluccana) oil with methanol using potassium hydroxide as catalyst was studied. The objective of the present investigation was to produce the methyl ester for use as biodiesel. The operation variables employed were methanol to oil molar ratio (3:1 – 9:1), catalyst concentration (0.50 – 1.5 %) and temperature (303 – 343K). Oil volume of 150 mL, reaction time of 75 min were fixed as common parameters in all the experiments. The concentration of methyl ester was evaluated by mass balance of free glycerol formed which was analyzed by using periodic acid. The optimal triglyceride conversion was attained by using methanol to oil ratio of 6:1, potassium hydroxide as catalyst was of 1%, at room temperature. Methyl ester formed was characterized by its density, viscosity, cloud and pour points. The biodiesel properties had properties similar to those of diesel oil, except for the viscosity that was higher.

Keywords: biodiesel, candlenut, methyl ester, transestrification

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474 Denitrification of Wastewater Containing High Nitrate Using a Bioreactor System Packed by Microbial Cellulose

Authors: H. Godini, A. Rezaee, A. Jafari, S. H. Mirhousaini

Abstract:

A Laboratory-scale packed bed reactor with microbial cellulose as the biofilm carrier was used to investigate the denitrification of high-strength nitrate wastewater with specific emphasis on the effect the nitrogen loading rate and hydraulic retention time. Ethanol was added as a carbon source for denitrification. As a result of this investigation, it was found that up to 500 mg/l feed nitrate concentration the present system is able to produce an effluent with nitrate content below 10 ppm at 3 h hydraulic retention time. The highest observed denitrification rate was 4.57 kg NO3-N/ (m3 .d) at a nitrate load of 5.64 kg NO3- N/(m3 .d), and removal efficiencies higher than 90% were obtained for loads up to 4.2 kg NO3-N/(m3 .d). A mass relation between COD consumed and NO3-N removed around 2.82 was observed. This continuous-flow bioreactor proved an efficient denitrification system with a relatively low retention time.

Keywords: Biological nitrate removal, Denitrification, Microbial cellulose, Packed-bed reactor.

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473 Gender Differences in Morbid Obese Children: Clinical Significance of Two Diagnostic Obesity Notation Model Assessment Indices

Authors: Mustafa M. Donma, Orkide Donma, Murat Aydin, Muhammet Demirkol, Burcin Nalbantoglu, Aysin Nalbantoglu, Birol Topcu

Abstract:

Childhood obesity is an ever increasing global health problem, affecting both developed and developing countries. Accurate evaluation of obesity in children requires difficult and detailed investigation. In our study, obesity in children was evaluated using new body fat ratios and indices. Assessment of anthropometric measurements, as well as some ratios, is important because of the evaluation of gender differences particularly during the late periods of obesity. A total of 239 children; 168 morbid obese (MO) (81 girls and 87 boys) and 71 normal weight (NW) (40 girls and 31 boys) children, participated in the study. Informed consent forms signed by the parents were obtained. Ethics Committee approved the study protocol. Mean ages (years)±SD calculated for MO group were 10.8±2.9 years in girls and 10.1±2.4 years in boys. The corresponding values for NW group were 9.0±2.0 years in girls and 9.2±2.1 years in boys. Mean body mass index (BMI)±SD values for MO group were 29.1±5.4 kg/m2 and 27.2±3.9 kg/m2 in girls and boys, respectively. These values for NW group were calculated as 15.5±1.0 kg/m2 in girls and 15.9±1.1 kg/m2 in boys. Groups were constituted based upon BMI percentiles for age-and-sex values recommended by WHO. Children with percentiles >99 were grouped as MO and children with percentiles between 85 and 15 were considered NW. The anthropometric measurements were recorded and evaluated along with the new ratios such as trunk-to-appendicular fat ratio, as well as indices such as Index-I and Index-II. The body fat percent values were obtained by bio-electrical impedance analysis. Data were entered into a database for analysis using SPSS/PASW 18 Statistics for Windows statistical software. Increased waist-to-hip circumference (C) ratios, decreased head-to-neck C, height ‘to’ ‘two’-‘to’-waist C and height ‘to’ ‘two’-‘to’-hip C ratios were observed in parallel with the development of obesity (p≤0.001). Reference value for height ‘to’ ‘two’-‘to’-hip ratio was detected as approximately 1.0. Index-II, based upon total body fat mass, showed much more significant differences between the groups than Index-I based upon weight. There was not any difference between trunk-to-appendicular fat ratios of NW girls and NW boys (p≥0.05). However, significantly increased values for MO girls in comparison with MO boys were observed (p≤0.05). This parameter showed no difference between NW and MO states in boys (p≥0.05). However, statistically significant increase was noted in MO girls compared to their NW states (p≤0.001). Trunk-to-appendicular fat ratio was the only fat-based parameter, which showed gender difference between NW and MO groups. This study has revealed that body ratios and formula based upon body fat tissue are more valuable parameters than those based on weight and height values for the evaluation of morbid obesity in children.

Keywords: Anthropometry, childhood obesity, gender, Morbid obesity.

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472 Parameters Affecting the Removal of Copper and Cobalt from Aqueous Solution onto Clinoptiloliteby Ion-Exchange Process

Authors: John Kabuba, Hilary Rutto

Abstract:

Ion exchange is one of the methods used to remove heavy metal such as copper and cobalt from wastewaters. Parameters affecting the ion-exchange of copper and cobalt aqueous solutions using clinoptilolite are the objectives of this study. Synthetic solutions were prepared with the concentration of 0.02M, 0.06M and 0.1M. The cobalt solution was maintained to 0.02M while varying the copper solution to the above stated concentrations. The clinoptilolite was activated with HCl and H2SO4 for removal efficiency. The pHs of the solutions were found to be acidic hence enhancing the copper and cobalt removal. The natural clinoptilolite performance was also found to be lower compared to the HCl and H2SO4 activated one for the copper removal ranging from 68% to 78% of Cu2+ uptake with the natural clinoptilolite to 66% to 51% with HCl and H2SO4 respectively. It was found that the activated clinoptilolite removed more copper and cobalt than the natural one and found that the electronegativity of the metal plays a role in the metal removal and the clinoptilolite selectivity.

Keywords: Clinoptilolite, cobalt and copper, Ion-exchange, mass dosage, pH.

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471 The Impact of Online Advertising on Consumer Purchase Behavior Based on Malaysian Organizations

Authors: Naser Zourikalatehsamad, Seyed Abdorreza Payambarpour, Ibrahim Alwashali, Zahra Abdolkarimi

Abstract:

The paper aims to evaluate the effect of online advertising on consumer purchase behavior in Malaysian organizations. The paper has potential to extend and refine theory. A survey was distributed among Students of UTM university during the winter 2014 and 160 responses were collected. Regression analysis was used to test the hypothesized relationships of the model. Result shows that the predictors (cost saving factor, convenience factor and customized product or services) have positive impact on intention to continue seeking online advertising.

Keywords: Consumer purchase, convenience, customized product, cost saving, customization, flow theory, mass communication, online advertising ads, online advertising measurement, online advertising mechanism, online intelligence system, self-confidence, willingness to purchase.

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470 Contact Drying Simulation of Particulate Materials: A Comprehensive Approach

Authors: Marco Intelvi, Apolinar Picado, Joaquín Martínez

Abstract:

In this work, simulation algorithms for contact drying of agitated particulate materials under vacuum and at atmospheric pressure were developed. The implementation of algorithms gives a predictive estimation of drying rate curves and bulk bed temperature during contact drying. The calculations are based on the penetration model to describe the drying process, where all process parameters such as heat and mass transfer coefficients, effective bed properties, gas and liquid phase properties are estimated with proper correlations. Simulation results were compared with experimental data from the literature. In both cases, simulation results were in good agreement with experimental data. Few deviations were identified and the limitations of the predictive capabilities of the models are discussed. The programs give a good insight of the drying behaviour of the analysed powders.

Keywords: Agitated bed, Atmospheric pressure, Penetrationmodel, Vacuum

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469 Current Deflecting Wall: A Promising Structure for Minimising Siltation in Semi-Enclosed Docks

Authors: A. A. Purohit, A. Basu, K. A. Chavan, M. D. Kudale

Abstract:

Many estuarine harbours in the world are facing the problem of siltation in docks, channel entrances, etc. The harbours in India are not an exception and require maintenance dredging to achieve navigable depths for keeping them operable. Hence, dredging is inevitable and is a costly affair. The heavy siltation in docks in well mixed tide dominated estuaries is mainly due to settlement of cohesive sediments in suspension. As such there is a need to have a permanent solution for minimising the siltation in such docks to alter the hydrodynamic flow field responsible for siltation by constructing structures outside the dock. One of such docks on the west coast of India, wherein siltation of about 2.5-3 m/annum prevails, was considered to understand the hydrodynamic flow field responsible for siltation. The dock is situated in such a region where macro type of semi-diurnal tide (range of about 5m) prevails. In order to change the flow field responsible for siltation inside the dock, suitability of Current Deflecting Wall (CDW) outside the dock was studied, which will minimise the sediment exchange rate and siltation in the dock. The well calibrated physical tidal model was used to understand the flow field during various phases of tide for the existing dock in Mumbai harbour. At the harbour entrance where the tidal flux exchanges in/out of the dock, measurements on water level and current were made to estimate the sediment transport capacity. The distorted scaled model (1:400 (H) & 1:80 (V)) of Mumbai area was used to study the tidal flow phenomenon, wherein tides are generated by automatic tide generator. Hydraulic model studies carried out under the existing condition (without CDW) reveal that, during initial hours of flood tide, flow hugs the docks breakwater and part of flow which enters the dock forms number of eddies of varying sizes inside the basin, while remaining part of flow bypasses the entrance of dock. During ebb, flow direction reverses, and part of the flow re-enters the dock from outside and creates eddies at its entrance. These eddies do not allow water/sediment-mass to come out and result in settlement of sediments in dock both due to eddies and more retention of sediment. At latter hours, current strength outside the dock entrance reduces and allows the water-mass of dock to come out. In order to improve flow field inside the dockyard, two CDWs of length 300 m and 40 m were proposed outside the dock breakwater and inline to Pier-wall at dock entrance. Model studies reveal that, during flood, major flow gets deflected away from the entrance and no eddies are formed inside the dock, while during ebb flow does not re-enter the dock, and sediment flux immediately starts emptying it during initial hours of ebb. This reduces not only the entry of sediment in dock by about 40% but also the deposition by about 42% due to less retention. Thus, CDW is a promising solution to significantly reduce siltation in dock.

Keywords: Current deflecting wall, eddies, hydraulic model, macro tide, siltation.

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468 A Family of Distributions on Learnable Problems without Uniform Convergence

Authors: César Garza

Abstract:

In supervised binary classification and regression problems, it is well-known that learnability is equivalent to uniform convergence of the hypothesis class, and if a problem is learnable, it is learnable by empirical risk minimization. For the general learning setting of unsupervised learning tasks, there are non-trivial learning problems where uniform convergence does not hold. We present here the task of learning centers of mass with an extra feature that “activates” some of the coordinates over the unit ball in a Hilbert space. We show that the learning problem is learnable under a stable RLM rule. We introduce a family of distributions over the domain space with some mild restrictions for which the sample complexity of uniform convergence for these problems must grow logarithmically with the dimension of the Hilbert space. If we take this dimension to infinity, we obtain a learnable problem for which the uniform convergence property fails for a vast family of distributions.

Keywords: Statistical learning theory, learnability, uniform convergence, stability, regularized loss minimization.

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467 An Investigation into Air Ejector with Pulsating Primary Flow

Authors: Václav Dvořák, Petra Dančová

Abstract:

The article deals with pneumatic and hot wire anemometry measurement on subsonic axi-symmetric air ejector. Performances of the ejector with and without pulsations of primary flow are compared, measuring of characteristic pressures and mass flow rates are performed and ejector efficiency is evaluated. The pulsations of primary flow are produced by a synthetic jet generator, which is placed in the supply line of the primary flow just in front of the primary nozzle. The aim of the pulsation is to intensify the mixing process. In the article we present: Pressure measuring of pulsation on the mixing chamber wall, behind the mixing chamber and behind the diffuser measured by fast pressure transducers and results of hot wire anemometry measurement. It was found out that using of primary flow pulsations yields higher back pressure behind the ejector and higher efficiency. The processes in this ejector and influences of primary flow pulsations on the mixing processes are described.

Keywords: Air ejector, pulsation flow

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466 Experimental Study of the Extraction of Copper(II) from Sulphuric Acid by Means of Sodium Diethyldithiocarbamate (SDDT)

Authors: S.Touati, A.H. Meniai

Abstract:

The present work presents the extraction of copper(II) from sulphuric acid solutions with Sodium diethyldithiocarbamate (SDDT), and six different organic diluents: Dichloromethane, Chloroform, Carbon tetrachloride, Toluene, xylene and Cyclohexane, were tested. The pair SDDT/Chloroform showed to be the most selective in removing the copper cations, and hence was considered throughout the experimental study. The effects of operating parameters such as the initial concentration of the extracting agent, the agitation time, the agitation speed and the acid concentration were considered. For an initial concentration of Cu (II) of 63 ppm in a 0.5 M sulphuric acid solution, both with a mass of the extracting agent of 20 mg, an extraction percentage of about 97.8 % and a distribution coefficient of 44.42 were obtained, respectively, confirming the performance of the SDDT-Chloroform pair.

Keywords: Copper (II), Distribution coefficient, Extraction, SDDT, Sulphuric acid.

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