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Data Services Middleware for Data Sharing in Peer-to-Peer Environment
No full textThe advances in network computing models evolve the way people are sharing their resources. Nowadays, users are considered as peers and as such they are able to share their processing power, their applications and their data with each other. File sharing model is one of P2P models that allow peers to share and exchange files between them. This model isn’t sufficient for current demands of sharing. It doesn’t benefit from the huge amount of data which was stored in data sources and located locally in peers’ machines. So, to take advantage of the data stored in heterogeneous and autonomous data sources that spread across the enterprise, we intend to develop in this thesis a middleware that facilitates data sharing between different users regardless of their heterogeneity. This middleware adopts a service-oriented architecture and relies on peer-to-peer computing techniques in order to provide a set of ready-made and easy to use components that allow inexperienced users to publish and advertize their own data sources as well as discover and consume those of others. Also, this middleware relies on process oriented approach to provide data service composition engine to deliver a semi-dynamic service composition. This type of service composition composes a set of data services to provide virtual data integration through a set of rich functionalities.
By using such middleware, sharing data services between peers will become more easily as well as more reliable in P2P environment. It masks the heterogeneity between peers and the heterogeneity between data sources. Moreover, it meets user’s need of data availability and data integration through service composition. However, the proposed middleware will be able to use from any peer interested in the providing and consuming data services, and wants to take advantages of data integration that obtain from heterogeneous data sources
Purification and biochemical characterization of a novel thermoactive fungal pectate lyase from Penicillium occitanis
No full textWe purified a novel, thermoactive pectate lyase (Pel), designated Pel1, from the hyperpectinolytic mutant (CT1) of Penicillium occitanis using single-step, anion-exchange chromatography. The purified Pel1 had a pI of 6.5 and a molecular mass of approximately 39 kDa as estimated by SDS-PAGE. The activity of Pel1 was assayed in the presence of several divalent cations at different concentrations. Although we noted that the tested divalent cations are required for maximum activity, we found that none of them could substitute for the effects of 2 mM Ca2+. Using three different carbon sources, our results showed that the highest level of Pel1 activity (434 U/ml) was obtained in a medium supplemented with apple pectin. With polygalacturonic acid, Pel1 exhibited a Km of 0.0199 mg/ml and a Vmax of 17.19 μmol/min/mg at pH 7.0. However, at pH 9.0, the Km and Vmax values were 0.0136 mg/ml and 19.23 μmol/min/mg, respectively. The optimum temperature and pH value required for maximal enzymatic activity were found to be 60 °C and pH 9.0, respectively. At this pH, the half-life time stability at 60 °C was measured to be 16.4 min. The novel Pel1 is very thermally stable and presents alkalophilic parameters; such features are rarely exhibited by fungal Pels.Persona
Review on some antioxidant plants growing in Arab world
No full textScientific
Research at King Saud University for the work through
the research group project NO RGP-VPP-060
تقويم برنامج إعداد معلم صعوبات التعلم بقسم التربية الخاصة
No full textهدفت الدراسة لتقويم برنامج إعداد معلم صعوبات التعلم بقسم التربية الخاصة في جامعة الملك سعود. وبعد دراسة كثير من الأدبيات المتعلقة ببرنامج صعوبات التعلم وتقويمها خلصت الباحثة إلى إعداد أداة مكونة من ثلاثة أجزاء.الجزء الأول يتكون من (4) أسئلة تقيم أهداف البرنامج, والخطة الدراسية والمقررات الدراسية, ثم استراتيجيات التدريس والتقنيات المستخدمة وأخيراً أساليب التقويم المستخدمة في التدريس. أما الجزء الثاني فيتكون من سؤالين تتعرف الباحثة من خلالهما عن مستوى الفائدة من المقررات المضمنة في الخطة لإعداد معلمي صعوبات التعلم للتعامل مع تلاميذ صعوبات التعلم والسؤال الثاني يناقش مدى ارتباط هذه المقررات بإكساب معلم صعوبات التعلم بالمهارات التي تؤهله لتدريس ذوي صعوبات التعلم. أما الجزء الثالث فمجموعة من الأسئلة المفتوحة التي تحدد الصعوبات ومؤهلات مشرف التدريب وقدرة البرنامج على إكساب المعلم المهارات الضرورية لنجاحه في عمله وأخيرا أي مقترحات يقترحها أفراد العينة. وقد تكونت العنيه من جميع أعضاء هيئة التدريس ومن في حكمهم وعينة من المعلمين والمشرفين الذين تخرجوا من القسم وكذلك جميع الطلاب المتوقع تخرجهم في الفصل الدراسي الأول للعام1430هـ/ 1431هـ الذي طبقت فيه الأداة. وقد توصلت نتائج الدراسة إلى أن البرنامج يحقق أهدافه. بينما رأى أفراد العينة ضرورة تطوير الخطة ومحتوى المقررات واستراتيجيات وأساليب التدريس والتقويم لتواكب الطموحات المرجوة ولتؤهل معلم المستقبل بشكل أكثر كفاءة. كما توصلت إلى ترتيب منطقيي لمدى الاستفادة والتطبيق لبعض المقررات. حيث جاءت المقررات ذات الصلة الوثيقة بالصعوبات في مراتب متقدمة وبمتوسطات مرتفعة. وختمت الدراسة بتحليل, إجابات الأسئلة المفتوحة وكان من أبرز توصيات هذه الدراسة ضرورة رفع كفاءة الخريجين واكسابهم المهارات الضرورية لتدريس ذوي صعوبات التعلم مهارات القراءة والكتابة والإملاء وحل المشاكل، وكذلك تطوير خطة البرنامج ومحتوى المقررات واستراتيجيات التدريس وأساليب التقويم
New oxorhenium(V) complex with Imidazol [NN] / Hydantion [SN] mixed ligand system , and radiochemical behavior of its oxotechentuim(V) complex analog
No full textA [ReO(Imz)(Hyd)(H2O)2OH] complex was successfully synthesized by the ligand exchange method using oxorhenuim citrate and an imidazole /Hydanton mixed ligand system. Geometry optimization of complex has been carried out using DFT at the B3LYP/LANL2DZ functional in singlet state. B3LYP predicated infrared spectrum of the geometrically optimized structure using the same level of the theory and the same base set showed good agreement with experimentally observed values. The spin allowed singlet-singlet electronic transition of the [ReO(Imz)(Hyd) (H2O)2OH] complex was calculated with time dependent density function theory (TD-DFT) and the UV-Vis spectra has been discussed on this basis. The complex was characterized using microanalysis and IR, UV-Vis, NMR and mass spectroscopic.
The technetium tracer [99mTcO(Imz)(Hyd) (H2O)2OH] has also been synthesized by two methods using 99mTc-gluconate as a precursor or; by direct reduction. The radiochemical purity of the complex was over 95% as measured by thin layer chromatography. In vitro studies showed that the complex possessed good stability under physiological conditions. The partition coefficient indicated that the complex hydrophilic and the electrophoresis results showed that the complex cationic. Biodistrbution in mice showed that the complex accumulated in heart uptake of 9.53±3.87 % ID/gm at 5 min and good retention (6.37±1.21) % ID/gm at 60 min. One hour after the injection, the heart/liver, heart/lung and heart/blood radioactivity ratios were 0.46, 1.04 and 0.56, respectively. These findings indicate that the complex might be suitable for myocardial imaging
Diabetes Mellitus and Hearing loss
No full textObjective: Diabetes mellitus is a common disease in Saudi population and hearing loss is one of the problems experienced by diabetics. In this study we evaluate the effect of duration, type of diabetes mellitus and age intervals on the auditory function of diabetics.
Materials& methods: A random sample survey of 110 Saudi females, 55 diabetics and 55 non-diabetics (control). Detailed history was taken and they were audologicaly tested this study was performed from October, 2009 to October, 2010.
Results: This study showed that diabetic patients had worse hearing thresholds than control group. The degree of hearing impairment correlated positively with duration and type of diabetes, however it did not affected by age.
Conclusion: Due to the high prevalence of diabetes mellitus in the Saudi community and the presence of hearing loss more among diabetics, it’s recommended to carry out a complete hearing evaluation for all diabetics and to repeat these tests regularly
Assessment of pulmonary function tests in cardiac patients
No full textThis study was aimed to assess the pulmonary function tests (PFTs) in cardiac patients; with ischemic or rheumatic heart diseases as well as in patients who underwent coronary artery bypass graft (CABG) or valvular procedures. For the forty eligible participants, the pulmonary function was measured using the spirometry test before and after the cardiac surgery. Data collection sheet was used for the patient’s demographic and intra-operative information. Cardiac diseases and surgeries had restrictive negative impact on PFTs. Before surgery, vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), ratio between FEV1 and FVC, and maximum voluntary ventilation (MVV) recorded lower values for rheumatic patients than ischemic patients (P values were 0.01, 0.005, 0.0001, 0.031, and 0.035, respectively). Moreover, patients who underwent valvular surgery had lower PFTs than patients who underwent CABG with significant differences for VC, FVC, FEV1, and MVV tests (P values were 0.043, 0.011, 0.040, and 0.020, respectively). No definite causative factor appeared to be responsible for those results although mechanical deficiency and incisional chest pain caused by cardiac surgery are doubtful. More comprehensive investigation is required to resolve the case
Balance performance of community-dwelling older people.
No full textObjectives: To investigate the association of 4 common clinical balance tests and history of fall in Saudi community-dwelling older people.
Methods: This retrospective study took place in the Rehabilitation Health Sciences Department, College of Applied Medical Sciences, King Saud University. Older people were recruited from Riyadh, Kingdom of Saudi Arabia from September 2009 to June 2010. Four balance performance tests were used. Inclusion criteria for 60-85 year-old participants (n=48) were checked.
Results: Fallers had lower balance performance than non-fallers in the test-battery measures with significance difference for one leg stance test with open (p=0.001) and closed eyes (p=0.0001). One leg stance with closed eyes test showed an overall prediction capability (83.2%), high sensitivity (79.2%), and specificity (87.5%).
Conclusion: This study shows that Saudi community-dwelling older people fallers had compromised balance performance, and that one leg stance test with closed eyes was the best balance test associated with history of fall
Obesity: Preventive Role Of Pomegranate (Punica Granatum) And Its Extracts
No full textObesity represents a rapidly growing threat to the health of populations in an increasing number of countries. Diet intervention has been proposed as one of the strategies for weight loss and weight maintenance. Traditionally, pomegranate including its roots, bark of the tree, the fruit juice, its leaf and flower has been used to treat a number of diseases such as diarrhea, hemorrhage, acidosis and microbial infections. Pomegranate extracts have been found to have strong anti-inflammatory, antioxidant and even anti-tumor properties both in in vivo and in vitro. More recently, positive effects on fat reduction have been shown using pomegranate and its extracts. Many of the beneficial effects are related to the presence of antocyanins, tannins and very high levels of antioxidants including polyphenols and flavoinoids. A number of studies have explored the effects of pomegranate in obesity and various mechanisms have also been proposed as to how these different extracts help in fat reduction.
This article provides an overview of the work done addressing the potential benefits of pomegranate on obesity and assesses the efficacy of intervention by pomegranate and its extracts. Human studies in this field are still limited and needs more attention and would help in understanding the preventive as well as protective role pomegranate extracts have on obesity
In Vitro Antimicrobial and Anti-Tumor Activities of Intracellular and
No full textFungi are known to produce a vast array of secondary metabolites that are gaining importance for their biotechnological applications. In the present study, the crude methanolic extracts of Aspergillus niger and Aspergillus flavus var. columinaris were tested by the disc diffusion method and minimal inhibitory concentration (MIC) determination for detection of antimicrobial activity against ten species of microorganisms: Escherichia coli ATCC 25922, Klebsiella pneumoniae ATCC 31488, Pseudomonas aeruginosa ATTC 27853,
Shigella dysenteriae ATCC 13313, Proteus vulgaris ATCC 6380, Salmonella typhimurium (LIO, locally isolated organism), Bacillus cereus ATCC 11778, Enterococcus faecalis (LIO), Staphylococcus aureus ATCC 25923 and Candida albicans ATCC 10231 and by the sulforhodamine B (SRB) assay method to test their in vitro anti-tumor activity. The extracellular extracts of both fungi showed their activity against Gram-negative bacteria only. The antibacterial activity of extracellular extract of Aspergillus flavus var. columinaris was higher than that of extracellular extract of Aspergillus niger. Candida albicans was sensitive to the intracellular extract of Aspergillus flavus var. columinaris. The extracellular extracts of both isolated fungi were having more cytotoxic effect than their intracellular extracts. IC50 (concentration of extract required to reduce cell survival
by 50%) of extracellular extract of Aspergillus niger was the most reducible one (0.905 μg/ml) followed by the extracellular extract of Aspergillus flavus var. columinaris (1.48 μg/ml). The IC50 of the intracellular extracts
was approximately similar among two isolates (3.50 μg/ml for Aspergillus niger and 3.03 μg/ml for Aspergillus flavus var. columinaris). In conclusion, the extracellular extract of Aspergillus flavus var. columinaris possesses
antibacterial activity against Gram-negative bacteria. While the extracellular extracts of Aspergillus niger and Aspergillus flavus var. columinaris have in vitro anti-tumor activity, which support their use in medicines. It is hoped that this study would lead to the establishment of some extracts that could be used to formulate new and more potent antimicrobial and anticancer drugs.King Saud Universit