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Search Results: 1 - 10 of 362728 matches for " J. I.; "
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Adjustment of Infiltration Models in Poorly Developed Soils  [PDF]
Alberto I. J. Vich
Open Journal of Modern Hydrology (OJMH) , 2013, DOI: 10.4236/ojmh.2013.31002
Abstract:

Infiltration is a fundamental component of the rainfall-runoff process. It was characterized through the adjustment and comparison of the Smith-Parlange, Green-Amptd, Philip, Horton and Kostiakov equations, using simulated rain in poorly developed soils from three geological formations and from different ages (Marino Fm., Mogotes Fm., quaternary cover). Trials with the rainfall simulator were run in piedmont areas west of the city of Mendoza. Adjustments were performed separately for each of the trials and globally for each surface cover. The adjustment was satisfactory when the observed and the simulated infiltration velocity curves were compared using lumped parameters. The Green-Amptd model exhibited the best behavior for the three covers, while the Smith-Parlange equation was the least accurate, al- though it had little dispersion in the prediction errors. The Kostiakov and Horton equations yielded satisfactory results in view of the fact that the development of the infiltration rate curve was simulated after the impoundment time was determined with the Green-Amptd formula. The Philip model is not consistent, with the exception of the results obtained for the Marino cover. In the post-calibration procedure the parameters showed no noticeable differences with respect to those obtained during calibration. In every case the relative squared error of the infiltration curve was very satisfactory, below 5%.

The Antihypertensive Effect of ASA Lasts Less than 24 Hours?  [PDF]
I. Suomela, J. Varis, I. Kantola
World Journal of Cardiovascular Diseases (WJCD) , 2015, DOI: 10.4236/wjcd.2015.53009
Abstract: Objectives: Some studies suggest that acetylsalicylic acid (ASA) administered in the evening may have a lowering effect on the blood pressure. The purpose of this study was to measure the effect of the time of ASA administration on blood pressure, markers of arterial stiffness as well as various plasma parameters. Methods and Results: The study included 34 patients (20 men and 14 women) ranging in age from 47 to 82 years. Low-dose ASA (50 - 250 mg/day) was used by all the patients, first in the morning and later in the evening for three months. Home, office and ambulatory blood pressure and pulse wave velocity (PWV) were measured. Compared with the morning administration of ASA, significantly lower office systolic blood pressure (p = 0.017) and significantly higher carotid-femoral PWV (p = 0.010) as well as plasma triglycerides (p = 0.002) were found after the evening administration. There were no statistically significant changes in the average ambulatory blood pressure values, carotid-radial PWV or other parameters measured. However, the time of ASA administration seemed to affect the circadian variation in blood pressure. Conclusions: The results suggest that ASA administration may lower blood pressure, but for less than 24 hours. Our results should be verified by larger, randomized studies.
Prevalence of Glucose-6-Phosphate Dehydrogenase (G6PD) Deficiency in India: A Systematic Review  [PDF]
I. I. Shah, J. Jarullah, B. Jarullah
Advances in Bioscience and Biotechnology (ABB) , 2018, DOI: 10.4236/abb.2018.99033
Abstract: Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency is the most common enzyme deficiency of human erythrocyte affecting more than 400 million people worldwide. In India, G6PD deficiency was first reported in 1963 and since then various investigations have been conducted across country. The objective of this work was to study the prevalence of G6PD deficiency in different ethnic, caste and linguistic groups of Indian population. A systematic search of published literature was undertaken and the wide variability of G6PD deficiency has been observed ranging from 0% - 30.7% among the different caste, ethnic, and linguistic groups of India. It was observed that the incidence of G6PD deficiency was found to be considerably higher among the tribes (9.86%) as compared to other ethnic groups (7.34%) and significantly higher in males as compared to females.
Modeling Structures and Spectra of Fluorescent Proteins in the Coordinate-Locking Cluster Approach: Application to the Photoswitchable Protein AsFP595  [PDF]
I. Topol, J. Collins, A. Nemukhin
Computational Molecular Bioscience (CMB) , 2012, DOI: 10.4236/cmb.2012.23008
Abstract: An interest in the fluorescent protein asFP595 is due to unexplained puzzles in its photophysical behavior. We report the results of calculations of structures, absorption, and emission bands in asFP595 by considering model molecular clusters in the coordinate-locking scheme. Both trans and cis conformations of the anionic chromophore are considered. Equilibrium geometry coordinates on the ground potential energy surface were optimized in the density functional theory approaches by considering both large- and reduced-size clusters. The cluster size was reduced to locate positions of the minimum energy points on the excited-state potential surface by using the configuration interaction singles approach. Vertical excitation energies and oscillator strengths were computed by using the ZINDO method. We show that consideration of large clusters mimicking the protein-containing pocket is an essential issue to calculate positions of absorption and emission bands with the accuracy compatible to experiments.
Sustainable Polymers Derived From Naturally Occurring Materials  [PDF]
Bimlesh Lochab, I K. Varma, J. Bijwea
Advances in Materials Physics and Chemistry (AMPC) , 2012, DOI: 10.4236/ampc.2012.24B056
Abstract:

Nearly 95% of monomers or chemical intermediates used today are based on fossilized carbon such as coal and petroleum. This has resulted in a high rate of depletion of fossilized reserves, continuous escalation in petroleum prices, environmental impact with the increase in emission of greenhouse gases, and accumulation of non-biodegradable waste on earth. Current global main challenges are moving towards green sources - need for vast new and sustainable material resources; supplement, reuse and replace petroleum based polymeric materials; biodegradability of materials to prevent build up of waste; toxicity associated with the preparation, usage and environmental safety. Recent investigations are therefore, focused on procuring materials from the plant resources, agricultural waste and their utility in synthesis of polymeric materials. Amongst the polymers derived from natural resources poly(lactic acid) is a leading candidate. Commercial quantities of natural oil-based polyols such as castor, soya bean oil have been available over the past several years and currently used for synthesis of  polyesters, polyurethanes etc, but today many other  natural materials are also being investigated. It should be possible to produce sustainable polymers commercially and economically.

 

 


 

Impact of Climate Change on Aquatic Fauna of Economic Importance in Niger Delta, Nigeria  [PDF]
E. I. Elenwo, J. A. Akankali
Atmospheric and Climate Sciences (ACS) , 2014, DOI: 10.4236/acs.2014.44064
Abstract:

The study discusses the impact of climate change on aquatic lives in the Niger Delta region. To realise this, the study basically adopted a library search design of reviewing literatures of climate change impact on aquatic lives in the Niger Delta region. Meteorological data (rainfall, temperature and humidity) were also extracted from literatures to explain the evidence of climate change in the areas. The meteorological data showed that, temperature, rainfall and humidity have changed over the last 10 years. This change translates to climate change because it is at least up to a decade (10-year period), and it showed a 1.5°C rise in temperature from 2003 to 2013 and an increase of 342.2 mm in the amount of rainfall in Niger Delta. These clearly paint the picture of global warming. Furthermore, in the same period, there was a decrease of 9% in the amount of humidity in the area. Thus, it is very clear that the climate is changing over time within this region. This certainly has some effects on the aquatic Fauna in the region. In fact, for the next 10 years, the aquatic fauna that now inhabit various habitats may no longer be able to adapt to the changes, leading to their extinction and total elimination from the habitats in question. And as such, these aquatic fauna will either modify their body structure and function in order to tolerate the change in climate, migrate to new and comfortable habitat or even stand the risk of becoming extinct. To abate the impact of climate change in the region, introduction of new water management reform and policy implementation, and carbon sequestration amongst others were recommended. This electronic document is a “live” template. The various components of your paper [title, text, heads, etc.] are already defined on the style sheet, as illustrated by the portions given in this document.

Modeling and Simulation of Mechanical Properties of Nano Particle Modified Polyamide 6  [PDF]
I. Yi, J. Wiedmaier, S. Schmauder
Journal of Materials Science and Chemical Engineering (MSCE) , 2015, DOI: 10.4236/msce.2015.31012
Abstract:

This paper discusses the utilization of nano-sized fillers in Polyamide 6 to increase the fracture resistance of the composites, which are crucial for various engineering applications. The toughening of the composites is achieved by using dispersed nano-scaled rubber particles (Polyether block copolymer) as the inclusion in Polyamide 6 matrix. For a better understanding of the mechanical behavior of the composites, it is indispensable to use analytical and numerical models for evaluating the overall mechanical behavior and damage mechanism of the composite. In this work the toughening mechanism is studied through literature review and by analytical modeling. The mechanical behavior of the composites such as elastic plastic and damage properties are calculated numerically with 3D representative volume element (RVE) models. The numerical results are compared with previously obtained experiments. The influence of volume fraction and aspect ratio of inclusions on the macroscopic stress strain curve as well as the size effect of inclusions and also the failure properties of the composite are studied in detail.

Sources of Marine Pollution on Nigerian Coastal Resources: An Overview  [PDF]
J. A. Akankali, E. I. Elenwo
Open Journal of Marine Science (OJMS) , 2015, DOI: 10.4236/ojms.2015.52018
Abstract: Little is known about the full impacts of marine litter, especially in the open ocean where there is almost no information. The ocean is a vital source of nourishment, especially to the people in the world’s poorest nations. Many depend on fish for their source of protein; fisheries and aquaculture support the livelihoods of about 540 million people directly or indirectly[1]. Overfishing, loss of biodiversity and possible extinction of species put stress on these limited resources. Some beaches are already closed to public because the water is unsuitable for bathing and beach is covered with litters of plastics, discharge of sewage, agricultural run-off, and discharge of nutrients and pesticides accounts for approximately 80% of marine pollution[2]. The scenario is not different in Nigeria as there are reported cases of major industries such as fertilizer and petrochemical and oil producing companies that have polluted the marine environment in recent times. Therefore, this paper advocates by way of education and enlightenment to the populace the myriad of problems associated with marine pollution in the Nigerian coastal waters. Some suggested solution includes education, laws and collaboration amongst organization to create a sustainable marine ecosystem in Nigeria.
Analytical and Computational Analysis of Flow Splitting in Multiple, Parallel Channels Systems  [PDF]
Alejandro I. Lazarte, J. C. Ferreri
World Journal of Nuclear Science and Technology (WJNST) , 2016, DOI: 10.4236/wjnst.2016.63019
Abstract: Previous analytical results on flow splitting are generalized to consider multiple boiling channels systems. The analysis is consistent with the approximations usually adopted in the use of systems codes (like RELAP5 and TRACE5, among others) commonly applied to perform safety analyses of nuclear power plants. The problem is related to multiple, identical, parallel boiling channels, connected through common plena. A theoretical model limited in scope explains this flow splitting without reversal. The unified analysis performed and the confirmatory computational results found are summarized in this paper. New maps showing the zones where this behavior is predicted are also shown considering again twin pipes. Multiple pipe systems have been found not easily amenable for analytical analysis when dealing with more than four parallel pipes. However, the particular splitting found (flow along N pipes dividing in one standalone pipe flow plus N?-1 identical pipe flows) has been verified up to fourteen pipes, involving calculations in systems with even and odd number of pipes using the RELAP5 systems thermal-hydraulics code.
An Evaluation of Air Pollution Tolerance Index and Anticipated Performance Index of Some Tree Species Considered for Green Belt Development: A Case Study of Nandesari Industrial Area, Vadodara, Gujarat, India  [PDF]
Dhruti Patel, J. I. Nirmal Kumar
Open Journal of Air Pollution (OJAP) , 2018, DOI: 10.4236/ojap.2018.71001
Abstract: It is well renowned that trees have capacity to reduce the air pollution. It is mandatory to expand tree plantation in industrial area to minimize the threat of pollutants. For green belt development, it is necessary to use plants that are tolerant to air pollution. The present study includes Air pollution tolerance index (APTI) of selected plant species with the help of biochemical analysis. On the basis of APTI and some other socioeconomic and biological parameters of plants, Anticipated Performance Index (API) was calculated. Out of twelve species, Ficus benghalensis showed to be the most efficient among others. As per classification of API, Ficus religiosa tree species is classified into the moderate category. Based on the APTI and API, appropriate plant species for green belt development in industrial area were identified and recommended for mitigating the pollution.
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