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القانون الدولي ألاتفاقي ومشاكل الإثبات في التجارة الإلكترونية"
No full textيتمثل عنوان بحثنا في القانون الدولي الاتفاقي ومشاكل الإثبات في التجارة الإلكترونية" . وتتجلي أهمية هذا الموضوع في أن هناك تناقضات كثيرة فيما بين الاتفاقيات الدولية سواء في شأن إجراءات ووسائل الإثبات أو بخصوص تنقيح أو تعديل تلك الاتفاقيات، مما يترتب عليه صعوبة تطبيقها في مجال عقود التجارة الإلكترونية التي تتم عبر شبكات الاتصال الإلكترونية.
ونتيجة لذلك أجمعت الآراء على عدم ملاءمة إجراء تعديل لمختلف الاتفاقيات التي تتضمن مفاهيم – الكتابة والتوقيع والمستند – حسب كل حالة على حدَة؛ لأن هذا الإجراء سيكون مرهونا بالخطوات المنصوص عليها في الاتفاقية المراد تعديلها، وبالتالي لن يكون هناك مفهومًا موحدًا لهذا التعديل. هذا بالإضافة إلى أن تحقيق الانسجام بين الاتفاقيات المعنية سيحتاج إلى سنوات عديدة، وأثناء ذلك، سيكون هناك المزيد من عدم اليقين القانوني. وترتيباً على ما تقدم, نعتقد أن إصلاح تلك الاتفاقيات وتطويعها لتقبل التطبيق في الوسط الإلكتروني يمكن أن يتحقق من خلال وضع "اتفاق تفسيري" يتجلى فيه إيضاح وافٍ لتلك المفاهيم، على أن يكون مفهوماً أن هذا الاتفاق يحدث تغييراً في التفسيرات القائمة لا مجرد توضيح لها. وهذا الحل يجد سنداً له اتفاقية فيينا لقانون المعاهدات لسنة 1969, ومؤتمر لاهاي للقانون الدولي الخا
Activity and carbon formation of A Low Ni-Loading Alumina-Supported
No full textOxidative carbon dioxide reforming of methane to synthesis gas over alumina-supported Ni catalysts was investigated at atmospheric pressure. The reforming reactions were carried out using a CO2 to CH4 feed ratio of one and reaction temperatures range of 600-800°C. The activity and stability of the catalyst, carbon deposition, and synthesis gas (H2/CO) ratio were determined. Catalyst deactivation was primarily due to coke formation. EDS, SEM and TGA techniques were used to confirm carbon deposition. It was observed that increasing the oxygen feed concentration and/or reaction temperatures, enhanced methane conversion and reduced coke formation. Catalyst stability test revealed that the highest CH4 conversion of 99.7% associated with the lowest drop in CH4 conversion of 1% and lowest carbon formation of 1% were obtained when 20% O2 was introduced with the feed at 800°C
Comparative bioavailability study of cefuroxime axetil (equivalent to 500 mg cefuroxime/tablet) tablets (Zednad® versus Zinnat®) in healthy male volunteers
No full textThis study was performed to investigate the bioequivalence of cefuroxime axetil tablets between a generic test product (A) Zednad® Tablet (500 mg cefuroxime/ tablet, Diamond Pharma, Syria), and the Reference Product (B) Zinnat® Tablet (500 mg cefuroxime/tablet, GlaxoSmithKline, Saudi Arabia). The bioavailability study was carried out for 24 healthy male volunteers. The subjects received 1 Zednad® Tablet (500 mg/ tablet) and 1 Zinnat® Tablet (500 mg/tablet) in a randomized, two-way crossover design fashion on 2 treatment days, after an overnight fast of at least 10 h, with a washout period of 7 days. 24 volunteers plus 2 alternatives completed the crossover. The bioanalysis of clinical plasma samples was accomplished by HPLC method, which was developed and validated in accordance with international guidelines. Pharmacokinetic parameters, determined by standard non-compartmental methods, and ANOVA statistics were calculated using SAS Statistical Software. The significance of a sequence effect was tested using the subjects nested in sequence as the error term. The 90% confidence intervals for the ratio between the test and reference product pharmacokinetic parameters of AUC0→t, AUC0→∞, and Cmax were calculated and found to be within the confidence limits of 80.00 - 125.00% for AUC0→t, AUC0→∞ and Cmax. The study demonstrated that the test product (A) was found bioequivalent to the reference product (B) following an oral dose of 500 mg tablet. Therefore, the two formulations were considered to be bioequivalent
Sample stacking microemulsion electrokinetic capillary chromatography induced by reverse migrating pseudostationary phase for the quantification of phenobarbital and its p-hydroxyphenobarbital metabolite in rat urine
No full textFor the first time, a capillary electrophoretic (CE) method with sample stacking induced by a reverse migrating pseudostationary phase (SRMP) technique has been developed and validated for sensitive determination of phenobarbital (PB) and its p-hydroxyphenobarbital (PHPB) metabolite in rat urine samples. Separation and determination were optimized on a fused-silica capillary with a total length of 50 cm (effective length 40 cm) and 75 μm ID. The microemulsion background electrolyte consisted of 0.8% (v/v) ethyl acetate, 6.6% (v/v) butan-2-ol, 1.0% (v/v) acetonitrile, 2.0% (w/v) sodium n-dodecyl sulfate (SDS), and 89.6% (v/v) of 7.5 mM ammonium formate at pH 8. When this preconcentration technique was used, the sample stacking and the separation processes took place successively with changing the voltage with an intermediate polarity switching step. For practical application, a solid-phase extraction (SPE), C18 sorbent with n-hexane/ethyl acetate (1 : 1%, v/v) as the elution solvent was used for sample purification and concentration. The SPE method gave good extraction yields for all the analytes, with absolute recovery values of 96.9% and 99.1% for PB and PHPB, respectively. The regression equations for PB and PHPB showed excellent linearity over a concentration range of 55–1386 ng mL−1 for PB and PHPB (r = 0.998). The developed microemulsion electrokinetic capillary chromatography (MEEKC) method for separation of the studied compounds with SRMP as the electrophoretic preconcentration technique allowed detection limits in urine samples at 16.8 ng mL−1 for PB and PHPB which are 15-fold lower than the reported CE method in the literature. The precision results, expressed by the intra-day and inter-day relative standard deviation (RSD) values range from 3.6 to 7.1% (repeatability) and from 3.2 to 7.2% (intermediate precision) for PB and PHPB, respectively, which were in line with Food and Drug Administration (FDA) criteria
Sentence Boundary Detection in Colloquial Arabic Text: A Preliminary Result
No full textRecently, natural language processing tasks are more frequently conducted over online content. This poses a special problem for applications over Arabic language. Online Arabic content is usually written in informal colloquial Arabic, which is characterized to be ill-structured and lacks specific linguistic standardization. In this paper, we investigate a preliminary step to conduct successful NLP processing which is the problem of sentence boundary detection. As informal Arabic lacks basic linguistic rules, we establish a list of commonly used punctuation marks after extensively studying a large amount of informal Arabic text. Moreover, we evaluated the correct usage of these punctuation marks as sentence delimiters; the result yielded a preliminary accuracy of 70%.King Saud Universit
Mobile Devices Exploitation by Malware
No full textIn recent years, mobile phones have evolved from supporting only telephonic functions to supporting multiple features, ranging from capturing and playing digital media, to e-mail access, to e-banking [10,11], to remote access to personal files. As the capabilities of mobile phones increased, the threat of more and more malicious software (malware) targeting them also increased. It is widely believed that the evolution of malware for mobile devices will take a similar direction as the evolution of PC malwares. Because mobile phones now have all the features of modern PCs connected to Internet. Many critical operations such as financial transactions, online selling and buying of goods are being done excessively through mobiles. Therefore security is one of the most important issues to be considered for mobiles. The security issues of mobile phones is very much similar to the ones that arise with the PCs. Open platforms are becoming popular in Smartphones, for example the Symbian Operating System is used in millions of mobile phones.
The mobile viruses discovered so far have little damaged as they require explicit user interaction for installation and activation. However, potential harm from future malware can be severer in the form of handset downtime, service disruption due to Denial of Service (DoS) attacks, and theft of sensitive data on the device. Similar to e-mail viruses, these malware may also target Short Messaging Service/ Multimedia Messaging Service (SMS/MMS) for distributing spam and phishing messages
Rheological and mucoadhesive characterization of poly(vinylpyrrolidone) hydrogels designed for nasal mucosal drug delivery
No full textPoly(vinylpyrrolidone) (PVP) hydrogels were crosslinked by gamma irradiation to add structure and rigidity, and then rheological and mucoadhesive properties were evaluated. The effects of PVP concentration, radiation dose, and additives, such as poly(ethylene glycol) (PEG) and glycerol, on rheological properties were investigated. In an oscillatory analysis, an increase in polymer concentrations increased the storage modulus (G') and the loss modulus (G″) but decreased the loss tangent (tan δ < 1). The relationships between G'or G″ and the frequency levelled off at higher frequencies, which is indicative of polymer chain entanglement and network formation. Each of the 6% PVP hydrogels exhibited plastic flow with rheopectic behavior. PVP concentration, radiation dose, and the presence of PEG or glycerol influenced the rheological and mucoadhesive properties of the hydrogels. However, adding acyclovir to the formulation did not have a profound effect on the rheological behavior of the hydrogels. The results suggest that a 3% PVP hydrogel with 1% PEG crosslinked with 20 kGy is the most appropriate hydrogel. The results demonstrated the successful complementary application of oscillatory and flow rheometry to characterize and develop a hydrogel for mucosal drug administration.
DOI: 10.1007/s12272-011-0407-
Mobile Devices Exploitation by Malware
No full textIn recent years, mobile phones have evolved from supporting only telephonic functions to supporting multiple features, ranging from capturing and playing digital media, to e-mail access, to e-banking [10,11], to remote access to personal files. As the capabilities of mobile phones increased, the threat of more and more malicious software (malware) targeting them also increased. It is widely believed that the evolution of malware for mobile devices will take a similar direction as the evolution of PC malwares. Because mobile phones now have all the features of modern PCs connected to Internet. Many critical operations such as financial transactions, online selling and buying of goods are being done excessively through mobiles. Therefore security is one of the most important issues to be considered for mobiles. The security issues of mobile phones is very much similar to the ones that arise with the PCs. Open platforms are becoming popular in Smartphones, for example the Symbian Operating System is used in millions of mobile phones.
The mobile viruses discovered so far have little damaged as they require explicit user interaction for installation and activation. However, potential harm from future malware can be severer in the form of handset downtime, service disruption due to Denial of Service (DoS) attacks, and theft of sensitive data on the device. Similar to e-mail viruses, these malware may also target Short Messaging Service/ Multimedia Messaging Service (SMS/MMS) for distributing spam and phishing messages
Author Assertion of furtive Write Print Using Character n-Grams
No full textThe exceptionality of shape and style of authors can be used for author's identification. The goalmouth of authorship attribution is to identify a set of features that remain relatively constant among a number of writings by a particular author. This paper deals with text author identification problem using character n-grams. However, the commonly usage is total n-gram for identification purpose but we consider all types of n-grams e.g. initial, medial, final and total bi.grams and tri.grams. Experiments show that authors profiles generated with initial bi.grams and initial tri.grams are effective in identifying texts authors in comparison with other n-gram profiles. The results disclosed in this paper leads to approximate 100% accuracy in identifying the author from unknown text.King Saud Universit