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Theophylline colon specific tablets for chronotherapeutic treatment of nocturnal asthma.
No full textThe ultimate goal is to design a new chronotherapeutic system for theophylline (TPH) with high potential benefits in treating nocturnal asthma. TPH core tablets were prepared by wet granulation using a developed formula. Compression coating over core tablets containing 200 mg TPH was done using granulated chitosan with 10% PVP K30. Different formulae F1, F2 and F3 were prepared using coat weights 260, 300 and 360 mg, respectively. The in vitro release characteristics in both variant pH media mimicking the gastrointestinal media and in media containing rat cecal content were monitored. The in vivo performance of the optimum formula was compared with Avolen(®) SR in Beagle dogs. F3 with high coat thickness exhibited a minimal release after 5-h release study. Both F2 and F3 showed more than 50% drug release after 4 h in the rat cecal medium. This reflects the colon selectivity of the system. The C(max) values were found to be 5.49 ± 0.46 and 5.12 ± 0.85 μg/mL for F3 and Avolen(®) SR, respectively, F3 showed higher mean plasma concentration than Avolen(®) SR from the beginning and continued till 7 h post administration indicating high potential as chronotherapeutic treatment of nocturnal asthma.
DOI: 10.3109/10837450.2011.57289
Phytochemical Analysis and In Vitro Antimicrobial and Free-Radical-Scavenging Activities of the Essential Oils from Euryops arabicus and Laggera decurrens.
No full textThe essential oils of the aerial part of two Asteraceae species, namely Euryops arabicus Steud. and Laggera decurrens (Vahl.) Hepper and Wood, were studied by GC and GC/MS. In parallel the antimicrobial and antioxidant activities were evaluated. The investigation led to the identification of 48 and 44 compounds for both plants, respectively. The essential oil of E. arabicus was rich in oxygenated sesquiterpenes (39.9%). The oil also contained a high content of sesquiterpene hydrocarbons (24.1%). Compounds such as caryophyllene oxide (8.6%), T-cadinol (7.0%), spathulenol (5.2%), (E)-β-caryophyllene (6.0%) and 2-epi-(E)-β-caryophyllene (6.0%) were the main constituents of the oil. Oxygenated monoterpenes also predominated in L. decurrens (46.3%). The thymoquinone-derivative, 3-methoxy-2-methyl-5-(1-methylethyl)-2,5-cyclohexadiene-1,4-dione (28.1%), thymol (5.7%) and eudesma-11-en-4a-ol (7.0%) were the most abundant constituents. Both essential oils showed antimicrobial activity with MIC-values between 0.13-5.25 mg/mL. Furthermore, only the essential oil of L. decurrens exhibited a strong antioxidant activity (91%) at 500 µg/mL.
DOI: 10.3390/molecules1606514
Incorporating Prisoners' Dilemma in Peer-Assessment: an Experimental Study
No full textAbstract
In this paper, we will discuss a new approach for peer assessment based on the well-known Prisoners' Dilemma game. The approach uses collaborative translation activity assisted by prisoner's dilemma game. The result shows an overall satisfaction of the new knowledge gained in this activity, where more than 70% of the students acknowledge that the activity increased their understanding of the subject knowledge.King Saud Universit
A Review of Malicious Code Detection Techniques for Mobile Devices
No full textWith the advent and rising popularity of wireless systems, there is a proliferation of small-enabled devices such as PDAs, mobile phones, etc. While these devices are becoming more and more preferable by all age groups, they also pose the threat of being vulnerable to malicious code (e.g.: viruses, trojans, worms, etc). In fact, the mobile devices rely on open and public transmission media. Besides, open platforms are becoming popular in smart phones. In this context, these devices have become more capable, providing users with all conveniences, ranging from traditional phone usage to supporting multiple features like e-mail access, playing games, software downloading and also e-banking. As the capabilities of these devices increase, the threat of malicious code (also called malware) targeting them also increased. It is believed that the evolution of mobile malware will take a similar direction as the PC malware. In this paper, we conducted a questionnaire based survey to know about the mobile device security concern among the users. The results indicate a high awareness but a low use of strong security measures. Then, we explore the various mobile phone vulnerabilities. A review of malicious code detection techniques for mobile devices are presented and discussed.IEEE, IACSI
استخدام مجموعة المصنفات لمصادقة التوقيع الديناميكي
No full text. مع التطور والتقدم السريع في التكنولوجيا أصبحت تقريباً كل التعاملات رقمية، كما أصبحت الحاجة لأمن المعلومات ملحّة جداً. وعلاوة على ذلك فإن الأجهزة المتطورة التي تقوم بالتقاط التوقيع الديناميكي للشخص متاحة حالياً. ولذلك فإن الإعتماد على التوقيع الديناميكي لتحديد الهوية في الأنظمة الآمنة أصبح مسألة حاسمة. نهدف في هذة الورقة إلى بحث موضوع تحديد هوية الشخص سواءً بواسطة التحقق من توقيعه الديناميكي أوالتعرف على هذا التوقيع وذلك باستخدام مجموعة المصنّفات، حيث قمنا باستخدام مجموعة مصنفات والمكونة من شبكات عصبية احتمالية معتمدة على تحليل فيشر Fisher. وفي هذا البحث نقوم بدراسة مسألتين هامتين، الأولى هي كيف يتم بناء مجموعة المصنفات، وتتمحور الثانية حول كيفية اتخاذ القرار وذلك استناداً للتوقعات التي يتم الحصول عليها من كل من هذه المصنّفات. تم اختبار مجموعة المصنّفات باستخدام مجموعة البيانات أسفيسي(SVC) الخاصة بالتوقيعات الديناميكية وتم الحصول على نتائج جيدة جداً ومشجعة تعكس قدرة مجموعة المصنفات على حل المشكلة المتعلقة بمصادقة التوقيع الديناميكي.King Saud Universit
THE INFLUENCE OF ACADEMIC ORGANIZATIONAL CLIMATE ON NURSING FACULTIES COMMITMENT IN SAUDI ARABIA
No full textHigher education in the Kingdom of Saudi Arabia was established to enhance the nation‘s growth and well-being of Saudis. The nurse faculty in Saudi university and college settings have mission. Typically this mission covers teaching, research, and community service. The interaction of these factors may influence the climate of the academic setting and has impact on the organizational commitment of faculty. The purpose of this study is to examine how dimensions of organizational commitment is influenced by organizational climate and nurse faculty work role in nursing academic settings in Saudi Arabia.
Method: this study non-experimental descriptive crossactional correlational was conducted. Three oldest and largest universities under The Ministry of Higher Education responsibility were selected. Full-time nurse faculties employed in the selected universities were recruited to participate in the study.
Instrument: The Meyer and Allen Organizational Commitment Instrument (1993) and the Organizational Climate Description Questionnaire- Higher Education (partial) (Borrevik, 1972) were used for data collection. In addition, the Nursing Academic Index Form, which was develop by the researcher to collect the faculty characteristics and to measure work role. Self-reported survey procedures were used to collect the study data. Descriptive procedures, Pearson‘s product-moment correlation coefficients were used in this study.
Results: The mean age of nursing faculty is 36.86years and the majority is non Saudi. The results revealed that the high mean score of nursing faculty commitment was normative commitment followed by continuance commitment then affective commitment. In addition the results showed that the intimacy was reflect lowest mean score. Organizational climate of consideration, intimacy, and production emphasis were significantly related to all dimensions of organizational commitment affective, continuance, and normative organizational commitment.
Discussion and recommendations: With caution to the assumption regarding commitment impact on performance, this result designated that the nursing faculty commitment is obligation base and they have to do so but their commitment is not desire based and they want to. These findings have implications for the recruitment and retention of nurse faculty. Efforts should be made by university deans to match institutional and individual goals, and open discussions should take place between administrators and faculty about role expectations, criteria for permanent status and promotion, and other institutional rewards
Metformin attenuates streptozotocin-induced diabetic nephropathy in rats through modulation of oxidative stress genes expression.
No full textDiabetes mellitus is a group of metabolic diseases characterized by hyperglycemia resulting from defects in insulin secretion and/or action. One of the most important complications of this metabolic disease is diabetic nephropathy. Hyperglycemia promotes oxidative stress and hence generation of reactive oxygen species (ROS), which is known to play a crucial role in the pathogenesis of diabetic nephropathy. Recent studies have established that metformin, an oral hypoglycemic drug, possesses antioxidant effects. However, whether metformin can protect against diabetic nephropathy has not been reported before. The overall objectives of the present study are to elucidate the potential nephroprotective effect of metformin in a rat diabetic nephropathy model and explore the exact underlying mechanism(s) involved. The effect of metformin on the biochemical changes associated with hyperglycemia induced by streptozotocin was investigated in rat kidney tissues. In addition, energy nucleotides (AMP and ATP), and Acetyl-CoA in the kidney homogenates and mitochondria, and the mRNA expression of oxidative stress and pro-inflammatory mediators were assessed. Our results showed that treatment of normoglycemic rats with metformin caused significant increase in ATP, Acetyl-CoA, and CoA-SH contents in kidney homogenates and mitochondria along with profound decrease in AMP level. On the other hand, treatment of diabetic nephropathy rats with metformin normalized all biochemical changes and the energy status in kidney tissues. At the transcriptional levels, metformin treatment caused significant restoration in diabetic nephropathy-induced oxidative stress mRNA levels, particularly GSTα, NQO1, and CAT genes, whereas inhibited TNF-α and IL-6 pro-inflammatory genes. Our data lend further credence for the contribution of metformin in the nephroprotective effect in addition to its well known hypoglycemic action
استقلال ونهائية خطاب الضمان فى ضوء قواعد التجارة الدولية الموحدة
No full textنظرا لأهمية خطاب الضمان فى الميدان القانونى ، والدليل على ذلك الإشكالات التى يثيرها فى الحياة العملية ، ونظرا لأن إستعمال خطاب الضمان بصوره المختلفة أصبح شائعا فى أنحاء العالم وخاصة فى التجارة الدولية بين الشركات والبنوك ، كان من الضرورى البحث فى نظام خطاب الضمان من ناحية استقلاله ونهائيته . وقد سمح تحديد تعريف خطاب الضمان بإبراز التزام البنك المستقل والنهائى والبات فى خطاب الضمان كما تبين أن اهمية خطاب الضمان على الصعيد الداخلى والخارجى أمر ثابت وغير مشكوك فيه. وعند بيان التزام البنك المستقل تبين أن التزام البنك ليس تابعا لألتزام العميل فى وجوده وصحته ، ومن اهم نتائج التزام البنك المستقل قبل المستفيد استخلص أنه يمتنع على البنك التمسك بالمقاصة بين دين على المستفيد للعميل وبين قيمة خطاب الضمان ، كم لا يجوز للبنك التمسك بالمقاصة فى مواجهة المستفيد بدين مستحق للبنك فى ذمة العميل ، بيد أنه يجوز التمسك بالمقاصة بين دين على المستفيد للبنك - ناشئ بسبب علاقة اخرى بينهما – وبين قيمة خطاب الضمان ،ورغم ألاستقرار على استقلال التزام البنك إلا أن هذا الاستقلال يتراجع فى حالة غش المستفيد فى طلبه خطاب الضمان . وفى التزام البنك البات والنهائى فى خطاب الضمان تبين أنه بمجرد إصدار خطاب الضمان ووصوله إلى علم المستفيد ولم يرفضه ، أصبح حق المستفيد على الخطاب نهائيا لا رجوع فيه إلا إذا اتفق على غير ذلك فى نصوص خطاب الضمان وعبارات .
ومما لا شك فيه أن اعتبار التزام البنك الناشئ عن خطاب الضمان مستقلا وباتا فى مواجهة المستفيد يجعل الخطاب صالحا لتأدية الوظيفة التى نشأ من أجله
Effects of Calcination and Activation Temperature on Dry Reforming Catalysts
No full textThe effect of calcination temperatures on dry reforming catalysts supported on high surface area alumina Ni/γ-Al2O3 (SA-6175), was studied experimentally. In this study, the prepared catalyst was tested in a micro tubular reactor using temperature ranges of 500, 600, 700 and 800°C at atmospheric pressure, using a total flow rate of 33 ml/min. consisting of 3 ml/min of N2, 15 ml/min of CO2 and 15 ml/min of CH4. The calcination was carried out in the range of 500-900°C. The catalyst is activated inside the reactor at 500-800°C using hydrogen gas. It was observed that calcination enhances catalyst activity which increases as calcination and reaction temperatures were increased. The highest conversion was obtained at 800°C reaction temperature by using catalyst calcined at 900°C and activation at 700°C. The catalyst characterization conducted supported the observed experimental results
Investigation of Suitable Pretreatment for Dry Reforming of Methane Over Ni/Al2O3
No full textCarbon dioxide reforming of methane to synthesis gas over an alumina-supported 1% Ni-based catalyst was investigated at atmospheric pressure. The effects of activation and calcinations temperatures and the addition of calcium promoted on dry reforming catalysts supported on low surface area alumina Ni/α-Al2O3 (SA-5239) were studied experimentally. In this study, the prepared catalyst was tested in a micro tubular reactor at temperature ranges of 500, 600, 700 and 800°C, atmospheric pressure, using a total flow rate of 33 ml/min. of feed gas 3 ml/min of N2, 15 ml/min of CO2 and 15 ml/min of CH4. The calcination was carried out in the range of 500-900°C. The catalysts were activated inside the reactor at 500-800°C using hydrogen gas. It was observed that calcinations catalyst activity which increases as calcination and reaction temperatures were increased. It was found essential activating reforming catalysts with H2. The highest process activity was obtained at 800°C reaction temperature by using catalyst calcined and activated at 900°C and 700°C respectively. The addition of Ca promoter decreases the coke formation on catalyst, however, It initially reduces the activity. The catalyst characterization conducted supported the observed xperimental resultChin