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Search Results: 1 - 10 of 9706 matches for " Ahmed Selim "
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Groundwater Rising as Environmental Problem, Causes and Solutions: Case Study from Aswan City, Upper Egypt  [PDF]
Sayed A. Selim, Ali M. Hamdan, Ahmed Abdel Rady
Open Journal of Geology (OJG) , 2014, DOI: 10.4236/ojg.2014.47025

This paper examines the rise in the level of the groundwater in the Quaternary aquifer at Aswan city, Upper Egypt. Since the 1960’s, the areal extent of Aswan City and the urban populations are growing at a high pace which introduces new sources of water that increase groundwater recharge. As a result of leakages or infiltrations from different sources, the natural groundwater balance is overturned into an unbalance where the input to water table is comparatively much more than the natural groundwater flow towards the Nile River. The present study shows a variation in the groundwater level, from 1971 up to 2014, where the water table rising ranges between 12.55 and 13.69 m. Also, it shows an abrupt increase in the water levels in 2010 continuing up till now. The groundwater rising phenomena that happened in 2010 can be directly refereed to the cessation of groundwater pumping from El-Shallal wells, and to the reduction of pumping from KIMA factory wells. Generally, the rate of water rising is much higher in the western side of the city and in Kima factory area, where they are characterized by low relief and dense population. The most troublesome groundwater mounds under urban areas are likely to develop in low-lying areas of relatively high permeability aquifer, which is not exploited for water supply. These damages will become more widespread if the rising groundwater table remains uncontrolled. The environmental impact of the water rising includes: forming ponds in low lying areas (Kima and El Shallal ponds), flooding building’s basements, and inundating underground infrastructure. A general deterioration in groundwater quality was identified.

Study on Periodic MHD Flow with Temperature Dependent Viscosity and Thermal Conductivity past an Isothermal Oscillating Cylinder  [PDF]
Rubel Ahmed, Reaz Uddin, B. M. Jewel Rana, Rafrafin Selim, Sarder Firoz Ahmmed
World Journal of Mechanics (WJM) , 2016, DOI: 10.4236/wjm.2016.611030
Abstract: Temperature dependent viscosity and thermal conducting heat and mass transfer flow with chemical reaction and periodic magnetic field past an isothermal oscillating cylinder have been considered. The partial dimensionless equations governing the flow have been solved numerically by applying explicit finite difference method with the help Compaq visual 6.6a. The obtained outcome of this inquisition has been discussed for different values of well-known flow parameters with different time steps and oscillation angle. The effect of chemical reaction and periodic MHD parameters on the velocity field, temperature field and concentration field, skin-friction, Nusselt number and Sherwood number have been studied and results are presented by graphically. The novelty of the present problem is to study the streamlines by taking into account periodic magnetic field.
Circulating rotaviral RNA in children with rotavirus antigenemia
Ahmed Kamruddin,Bozdayi Gulendam,Mitui Marcelo T,Ahmed Selim
Journal of Negative Results in BioMedicine , 2013, DOI: 10.1186/1477-5751-12-5
Abstract: Background Rotavirus antigenemia is a common phenomenon in children with rotavirus diarrhea, but information is scarce on aspects of this phenomenon, such as genotype specificity, presence of intact viruses and correlation between genomic RNA and antigen concentration. Such information may help in understanding rotavirus pathogenesis and eventually be useful for diagnosis, treatment and prevention. Methods and findings Serum samples were collected from children who presented at hospitals with diarrhea. Antigenemia was present in 162/250 (64.8%) samples from children with rotavirus diarrhea. No specific rotavirus genotype was found to be associated with antigenemia. Rotavirus particles could not be found by electron microscopy in concentrated serum from children with high levels of antigenemia. In passaged rotavirus suspension a significant correlation (r = 0.9559; P = 0.0029) was found between antigen level and viral copy number, but no significant correlation (r = 0.001480; P = 0.9919) was found between antigenemia level and viral copy number in serum. When intact rotavirus was treated with benzonase endonuclease, genomic double-stranded (ds) RNA was not degraded, but when sera of patients with antigenemia were treated with benzonase endonuclease, genomic dsRNA was degraded, indicating genomic dsRNA was free in sera and not inside virus capsid protein. Conclusions Antigenemia is present in a significant number of patients with rotavirus diarrhea. Rotavirus viremia was absent in the children with rotavirus diarrhea who participated in our study, and was not indicated by the presence of antigenemia. The significance of circulating rotavirus antigen and genomic dsRNA in serum of patients with diarrhea deserves further study.
Utilization of Trimethylolpropane Based Hyperbranched Poly(Amine-Ester) as New Polymeric Admixture  [PDF]
Amal Amin Ibrahim, Ahmed El-Sayed Abdel-Magied, Mohamed Sayed Selim, Magdy Mohamed Hussein Ayoub
Open Journal of Organic Polymer Materials (OJOPM) , 2012, DOI: 10.4236/ojopm.2012.22004
Abstract: Hyperbranched poly(amine-ester) (HBPAE) was synthesized via pseudo-one-step process between trimethylolpropane as a core molecule and N, N-diethylol-3-amine methylpropionate as the AB2 branched monomer. The prepared polymer was analyzed by IR, GPC, 1H-NMR and thermal analysis (TGA and DSC). The performance of the polymer in cement was tested by measuring the effect of 1, 3 and 5 wt% of HBPAE solutions on the properties of Ordinary Portland Cement. Water of consistency, setting times, bulk density, apparent porosity, compressive strength and combined water content of the polymer/cement pastes were studied. The results showed that water of consistency and apparent porosity decreased while setting times, compressive strength, combined water and bulk density increased with the polymer addition.
An Evaluation on Antioxidant Activity, Total Phenolic and Total Flavaonoid Contents of Extracts from Adina cordifolia (Roxb.)  [PDF]
Md. Ali Akbar Hossain, Md. Selim Hossain, Kaniz Fatema, Benazir Ahmed Siddique, Hanif Sikder, Md. Sohel Sarker, Preeti Jain
American Journal of Plant Sciences (AJPS) , 2015, DOI: 10.4236/ajps.2015.65068
Abstract: In this study, in vitro antioxidant activity, total phenolic content and concentration of flavonoids of four different extracts of Adina cordifolia (Roxb.) were determined using spectrophotometric methods. Antioxidant activity of extracts was expressed as percentage of DPPH radicals’ inhibition and IC50 values (μg/ml). IC50 values ranged from 20.39 to 38.96 μg/ml. The total phenolic content ranged from 17.48 to 20.83 mg/g of dry weight of extract, expressed as gallic acid equivalents. The total flavonoid concentrations varied from 17.49 to 22.48 mg/g, expressed as quercetin equivalents. The significant linear correlation was confirmed between the values for the total phenolic content and antioxidant activity of plant extracts. Adina cordifolia (Roxb.) can be regarded as promising candidates for natural plant sources of antioxidants with high value.
Severity of Rotavirus Diarrhea in Children: One Year Experience in a Children Hospital of Bangladesh
Selim Ahmed,ARM Luthful Kabir,Aminur Rahman,Maleeha Hussain
Iranian Journal of Pediatrics , 2009,
Abstract: Objective:This study was conducted to determine the hospital prevalence, clinical severity and treatment outcome of rotavirus versus non-rotavirus diarrhea in children attending a secondary level children hospital of Bangladesh. Methods: Total 601 children aged from 1 month to 5 years with watery diarrhea were enrolled and their stool samples were analyzed by ELISA for rotavirus antigen. Findings: Total 601 children aged from 1 month to 5 years with watery diarrhea were enrolled and their stool samples were analyzed by ELISA for rotavirus antigen. Conclusion:Despite high prevalence of Rotavirus diarrhea in Bangladesh, majority of this illness can be managed at home and/or in primary health care centers, since clinical severity and outcome of rotavirus diarrhea remains similar to that of non-rotavirus diarrhea. This message is expected to reduce frequent and sometimes un-necessary referral of diarrhea patients to higher centers thereby saving the working hours of the attending parents as well as disease burden to children hospitals having limited beds against the huge demand.
Analytical Third Order Solution for Coupling Effects of Earth Oblateness and Direct Solar Radiation Pressure on the Motion of Artificial Satellites  [PDF]
Hadia Hassan Selim
International Journal of Astronomy and Astrophysics (IJAA) , 2014, DOI: 10.4236/ijaa.2014.43049
Abstract: Coupling effects of Earth oblateness and direct solar radiation pressure on the motion of an artificial satellite are evaluated. Secular and periodic terms are retained up to order three and two respectively, where the coefficient of the second zonal harmonic of the geopotential is considered of first order. The solution revealed the existence of secular terms at order three that arises from the couplings between terms, of lower orders, resulting from the solar radiation pressure.
Impedance Matched Compact ZIGZAG Multiband Inverted-F Antenna for WI-FI, Mobile Wimax, Bluetooth and WLAN Operations in Portable Devices
S.M. Shibbir Alam,Md. Selim Hasan,Bulbul Ahmed,Md. Kafil Uddin
International Journal of Ad Hoc, Sensor & Ubiquitous Computing , 2011,
Abstract: Multiband loaded inverted-F antennas suitable to be applied in a portable device as an internal antennahaving high gain property for mobile WiMAX , Wi-Fi, Bluetooth and WLAN operations are presented.Numerical simulation is carried out using method of moments in Numerical Electromagnetic Code(NEC-2). The proposed dual inverted-F antenna is suitable for 3.5/5 GHz and compact triple bandinverted-F antenna is for 2.4/3.5/5.2 GHz operations. Total areas occupied by the antennas are24mm×37mm and 29mm×37mm in case of dual IFA and triple IFA respectively. The antennas containan incredibly high peak gain of 7.72 dBi at 5 GHz band and the gain variations at all frequency bandsare less than 1 dBi . In addition, the antennas have satisfactory radiation characteristics at all thefrequency bands. Due to compact area occupied, the proposed antennas are promising to be embeddedwithin the different portable devices.
Histomorphological Studies on the Prostate Gland of Donkey Equus Asinus during Different Seasons
Alaa S. Abou-Elhamd,Ahmed O. Salem,Aziza A. Selim
Journal of Histology , 2013, DOI: 10.1155/2013/643287
Abstract: The objective of this study is to describe the histological and histochemical structures of the prostate gland during different seasons of the year. The experiment was carried out on the prostate gland of 24 sexually mature apparently healthy male donkeys (5 to 7 years) distributed over the four seasons of the year. The prostate gland was enveloped externally by a thick fibromuscular capsule. Fibromuscular septa arose from the deep aspect of the capsule dividing the prostate into variable numbers of lobules of different sizes and shapes. Each prostatic lobe was made up of compound tubuloalveolar glands and duct system. The secretory end pieces were lined with principal secretory cells with occasional few basal ones. The principal cells varied from columnar to cuboidal in shape, depending upon the studied season. The principal cells showed PAS-positive reactivity. Seasonal variations were observed in the height of the principal cell lining the secretory end pieces, in the interstitial tissue/glandular tissue ratio, and in the PAS reactivity in the principal cells. In conclusion, the prostate gland of donkey appeared more active during spring. This reactivity decreased during other seasons of the year. Minimal reactivity was recorded during winter. 1. Introduction The accessory genital glands were a series of glands situated between the vas deferens and the root of the penis. These glands are responsible for the secretion of the seminal plasma, which provides the substrate for conveying the sperm to the female and ensuring final maturation [1, 2]. The accessory genital glands of donkey were made up of ampulla ductus deferentis, seminal vesicles, prostate gland, bulbourethral glands, and urethral glands [3]. The secretory portions of the prostate were tubuloalveolar in rabbits [4], dogs [5], boars [6], elephants [7], bulls [8], equines [9], men [10], camels [11], and buffalo bulls [12]. In rams, the prostate was compound tubular [13], while in red deer and goats [14–16], it was of branched tubular type. The epithelial lining of the secretory end pieces varied from low cuboidal to high columnar cells as observed in rabbits, boars, elephants, bulls, common marmoset, camels, buffalo bulls, domestic animals, and men ([4, 6–8, 17–21], resp.). In dogs, the lining epithelium was simple, stratified, or pseudostratified [5, 22]. Frequently, flattened, large rounded, ovoid, wedged, or pyramidal-shaped cells were recorded between the lining cells of the secretory units of the prostate of dogs [22], shrew [23], camels [24], men [10], and buffalo bulls [17]. These
Deep Activity Recognition Models with Triaxial Accelerometers
Mohammad Abu Alsheikh,Ahmed Selim,Dusit Niyato,Linda Doyle,Shaowei Lin,Hwee-Pink Tan
Computer Science , 2015,
Abstract: Despite the widespread installation of accelerometers in almost all mobile phones and wearable devices, activity recognition using accelerometers is still immature due to the poor recognition accuracy of existing recognition methods and the scarcity of labeled training data. We consider the problem of human activity recognition using triaxial accelerometers and deep learning paradigms. This paper shows that deep activity recognition models (a) provide better recognition accuracy of human activities, (b) avoid the expensive design of handcrafted features in existing systems, and (c) utilize the massive unlabeled acceleration samples for unsupervised feature extraction. Moreover, a hybrid approach of deep learning and hidden Markov models (DL-HMM) is presented for sequential activity recognition. This hybrid approach integrates the hierarchical representations of deep activity recognition models with the stochastic modeling of temporal sequences in the hidden Markov models. We show substantial recognition improvement on real world datasets over state-of-the-art methods of human activity recognition using triaxial accelerometers.
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