Al Qurayyāt, Saudi Arabia
Al Qurayyāt, Saudi Arabia

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Ben Bacha H.,University of Sfax | Ben Bacha H.,Salman bin Abdul Aziz University
Desalination | Year: 2013

The present study investigates the dynamic functioning of a new solar desalination process based on the humidification/dehumidification (HD) principle. The design and the principle of working of the desalination system are described. The paper deals with the modeling, simulation aspects, and experimental validation of the main components of the system. Mathematical models were established including the mechanism of heat and mass transfer in the various components. These models use real meteorological data to predict the performance of a thermal solar driven system. Series of experiments were conducted and experimental results were then compared with the simulation results. Our findings showed that the developed models could be used to design and help in predicting the behavior of the installation in various meteorological conditions. © 2013 Elsevier B.V.


Ziyad S.,Salman Bin Abdul Aziz University | Kannammal A.,Coimbatore Institute of Technology
Advances in Intelligent Systems and Computing | Year: 2014

The omnipresence of high-speed Internet has paved a promising future for cloud computing. Cloud computing technology deals with providing software, platform, and infrastructure as a service to the clients. This ultimately leads to transmission of the client’s confidential data in the cloud. This factor is the motivation to provide a secure biometric authentication framework to the cloud. This paper proposes a multifactor biometric authentication system for cloud computing environment. The biometric features adopted here are palm vein and fingerprint. The idea is to handle the biometric data in a secure fashion by storing the palm vein biometric data in multicomponent smart cards and fingerprint data in the central database of the cloud security server. In order to enhance security, the part of biometric data matching process is performed on the card with Match-on-Card technology and data never leave the smart card. © Springer India 2014.


Hussain Z.,King Saud University | Khan M.I.,Innsbruck Medical University | Shahid M.,Salman bin Abdul Aziz University | Almajhdi F.N.,King Saud University
Genetics and Molecular Research | Year: 2013

DNA methylation is a fundamental epigenetic mechanism in regulating the expression of genes controlling crucial cell functions in cancer development. Gene silencing via CpG island methylation/demethylation in the promoter region is one of the mechanisms by which different genes are inactivated/activated in human cancers. Tissue inhibitor of metalloproteinase-2 (TIMP-2) is known to antagonize matrix metalloproteinase (MMP) activity and to suppress tumor growth, angiogenesis, invasion, and metastasis. TIMP-2 expression has been found to be both upregulated and downregulated in various cancers. The inconsistent TIMP-2 expression and unclear epigenetic regulation lead us to investigate its role in colorectal cancer in the presence of a methylating agent. Highly invasive human colorectal cells SW-620 were treated with the methyl donor S-adenosylmethionine (SAM) and its effect was evaluated by cell proliferation, cell cycle, invasion and migration assay. The ability of SAM to down regulate a panel of activated prometastatic, angiogenesis and growth- and cell cycle-regulatory genes was evaluated using end-point and real-time PCR. Treatment of SW-620 with SAM diminished cell proliferation and altered cell cycle kinetic G2/M phase cell cycle arrest. An in vitro matrigel invasion assay of SAM-treated cells showed a significant reduction in the invasive potential compared to untreated SW-620 cells. Treatment of SW-620 cells with SAM resulted in activation of TIMP-2 and inhibition of the expression of genes such as MMP (MMP-2, MT1-MMP), urokinase plasminogen activator, and vascular endothelial growth factors. The level of expression of tumor suppressor and apoptotic genes was not significantly higher compared to the untreated control. No changes in the levels of expression of genes (growth and cell cycle regulator), such as TGF-β, Smad2, Smad4, and p21 were observed. Our data support the hypothesis that TIMP-2, along with other prometastatic genes, is hypomethylated and expressed differently in colorectal cancer. Further in-depth analysis is warranted to confirm the promoter region CpG methylation pattern of the TIMP-2 gene. © FUNPEC-RP.


Qureshi S.,Salman bin Abdul Aziz University
World Journal of Medical Sciences | Year: 2013

The investigation on general and genetic toxicity of Bakhour smoke inhalation in Swiss albino mice was undertaken in view of the literature reports on adverse effects of incense smoke and a paucity of literature on the general and genetic toxicity of Bakhour. The present study was conducted on both the sexes of Swiss albino mice. Treatment included exposure to a dose of 115 gram Bakhour burning smoke for a period of 2 hour, daily for 7 days. The observations on toxicity involved; behavioral changes (autonomic responses, motor activity and central nervous system), effect on body and organ weight and rate of mortality. Micronucleus test was used to determine the genetic toxicity. The different parameters studied were subjected to statistical analysis with one way ANOVA and Post hoc Tukey-Kramer multiple comparison test. The sub-acute treatment with Bakhour smoke failed to induce any significant changes in the symptoms of general toxicity as compared to the control. The animals remained calm during the treatment. There was moderate increase in respiration and mild increase in pilo erection and allergic symptoms. There was no mortality and effect on body weight. But weight of lungs altered significantly. The treatment failed to affect the frequency of micronucleatedpolychromatic erythrocytes (PCE) and the ratio of PCE/normochromatic erythrocytes (NCE). The results of this preliminary report showed that Bakhour smoke is non- toxic. Nevertheless, there is a need for more extensive studies that include analyzing composition of Bakhour smoke, comparing the smoke of Bakhour with that of the smoke from other sources, in addition to extensive studies on chronic toxicity. © IDOSI Publications, 2013.


Rad A.,University of Technology Malaysia | Mohd Rahim M.S.,University of Technology Malaysia | Rehman A.,Salman Bin Abdul Aziz University | Altameem A.,King Saud University | Saba T.,Prince Sultan University
IETE Technical Review (Institution of Electronics and Telecommunication Engineers, India) | Year: 2013

With a wide variety researches on Image segmentation techniques in biomedical and bioinformatics area, it is important to analyze the performance of these approaches in specific problems. Image segmentation is one of the most significant processes of dental X-ray image analysis. Therefore, to obtain the proper result, it is required to perform the accurate and efficient segmentation approach which proved itself in the aspect of X-ray image segmentation. The aim of this review paper is to understand the different image segmentation approaches which have been used for dental X-ray image analysis over the past studies. In this paper, different available approaches of dental X-ray image segmentation, reviewed and their advantages, disadvantages, and limitations are discussed.


Ahmad S.,Salman Bin Abdul Aziz University
Bangladesh Medical Research Council Bulletin | Year: 2012

Antibiotic resistance of urinary tract pathogens has increased worldwide. The purpose of this study is to provide information regarding the causative agents of urinary tract infection in Kashmiri patients, identify the uropathogens responsible for the infection and study the antibiotic susceptibility patterns of the uropathogens. Clean voided mid-stream urine samples were collected from 2190 patients. The specimens were cultured and the isolates were identified using standard microbiological techniques. The antibiotic susceptibilities of the isolates were also determined. Of 2190 specimens, 591 (27%) showed significant growth upon culture. Approximately 84.1 % (497/591) of the 591 patients with UTI were females, most of which belonged to the 21-30 age group (206). The males accounted for 15.9% (94/591) UTI cases. Most of the male patients belonged to the 21-30 age group (34). The lowest incidence of urinary tract infections was seen among the 13-20 years age group. Throughout this study males accounted for only 16% of all UTI cases. Esherichia coli was the most predominant isolate, 53.8% followed by Klebsiella pneumoniae 22.4% and Pseudomonas aeruginosa 7.6%. All isolates were fully sensitive to ofloxacin, and more than 94% were sensitive to cefuroxime. Apart from group D Streptococcus , the overall response to ampicillin by all isolates was less than 15%. The prevalence of multi-resistant Pseudomonas aeruginosa in community-acquired urinary tract infections is increasing. All Pseudomonas aeruginosa isolates were fully susceptible to cefuroxime and ofloxacin. It is recommended that cefuroxime and ofloxacin or both are used in the blind treatment of urinary tract infection while awaiting the culture and sensitivity results. Concurrent with the necessary shift in the prescription pattern, attention should be paid to restriction of antibiotic abuse in the community to retard development of further drug resistance.


Neamah K.,University of Technology Malaysia | Mohamad D.,University of Technology Malaysia | Saba T.,Prince Sultan University | Rehman A.,Salman Bin Abdul Aziz University
3D Research | Year: 2014

Signature verification is an active research area in the field of pattern recognition. It is employed to identify the particular person with the help of his/her signature's characteristics such as pen pressure, loops shape, speed of writing and up down motion of pen, writing speed, pen pressure, shape of loops, etc. in order to identify that person. However, in the entire process, features extraction and selection stage is of prime importance. Since several signatures have similar strokes, characteristics and sizes. Accordingly, this paper presents combination of orientation of the skeleton and gravity centre point to extract accurate pattern features of signature data in offline signature verification system. Promising results have proved the success of the integration of the two methods. © 2014 3D Research Center, Kwangwoon University and Springer-Verlag Berlin Heidelberg.


Khan M.S.,Salman Bin Abdul Aziz University
Journal of Pure and Applied Microbiology | Year: 2014

Candida albicans is a widespread opportunistic pathogen in immunocompromised patients. ATPase activity and protein concentration using spectrophotometric method and antifungal activity by Microtitre/ELISA technique in terms of Minimum Inhibitory Concentration (MIC) was studied to understand the pattern of Candida albicans. Minimum Inhibitory Concentration for Clotrimazole and Nystatin showed 6.25μg/ml and 8.0μg/ml "respectively". At optimum pH (7.0) and temperature (28°C), 100% activity of ATPase was recorded. pH showed inverse relationship while temperature showed no remarkable variation of activity. ATPase was found to be 5.0% reduced by Clotrimazole, whereas Nystatin caused 39% inhibition at the optimum pH and temperature.


Ahmad S.,Salman bin Abdul Aziz University
Bangladesh Journal of Medical Science | Year: 2013

Background: Methicillin resistant Staphylococcus aureus (MRSA) is a multidrug resistant organism that threatens the effectiveness of antibiotics worldwide and is a threat in hospitals and long-term care settings. Aims: To determine the proportion of MRSA strains and their in vitro antibiotic susceptibility patterns against various antibiotics. Material and Methods: Different clinical specimens (n= 679) received at Al-Haram Diagnostic, Research and Training Center, Kashmir during a two year period commencing January, 2009 to December, 2010 were cultured, the isolates identified using standard microbiological techniques and their antibiotic susceptibilities determined. Results: Of the 679 specimens, Staphylococcus. aureus was isolated in 127 and 32 (25.2%) of these 127 were found be MRSA. No significant association with age or sex were observed in the MRSA positive specimens. MRSA were mainly isolated from burns, and skin and superficial soft tissue infections. MRSA isolates were found to be 100% sensitive to Vancomycin and 94%, 87%, 81%, 78% and 75% of isolates were resistant to Gentamycin, Tetracycline, Clindamycin, Erythromycin and Co-trimoxazole respectively. Conclusions: The relatively high proportion of MRSA and the associated antibiotic resistance seen in this study emphasizes the need for local or country based surveillance to characterize and monitor MRSA and to develop strategies that will improve MRSA treatment and control.


Alshaaer M.,University of Jordan | Alshaaer M.,Salman Bin Abdul Aziz University
Applied Clay Science | Year: 2013

The effect of immersion in alkali solution as a second-phase geopolymerization of kaolinite-based geopolymers on their properties was investigated in this study. The aim of this work was to improve the geopolymer properties by increasing both its resistance to water absorption and mechanical performance. It was found that immersion in alkali solution as a second-phase geopolymerization - or a secondary treatment - at 80° C for 1 h resulted in a high gain in compressive strength, and formation of secondary geopolymer gel. A dense stable layer,with severalmicrometers depth,was formed on the surface of kaolinite-based geopolymerwithout causing swelling or shrinkage. These surface and microstructural modifications led to reduction of water absorption and thus induced high durability. As a result of second-phase geopolymerization, the produced geopolymers exhibited an increase in compressive strength from 46MPa to 59MPa, and from 22MPa to 27MPa after drying and water immersion, respectively. The water absorption of the geopolymers decreased from 10% (w/w) to 4% (w/w), and the overall shrinkage after curing decreased from 0.18% to 0.01%. © 2013 Elsevier B.V.

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