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مخالفة الحاشية للمتن .. حضور عنترة وغيابه في المسرح العربي
No full textالمتأمل في المنجز الأدبي المسرحي في الوطن العربي ، بداية من مرحلة الريادة ، يرى للتراث حضوراً ظاهراً في مرحلة الريادة ، وتميزاً ملحوظاً في المراحل التالية عليها، ولعل ذلك راجع إلي قدرة التراث على تعميق دلالات العمل الأدبي، وزيادة تشعبها، بالإضافة إلى اتفاقه في طبيعته مع المسرح اتفاقاً كبيراً.
ولعل أكثر الشخصيات التي استحضرها ووظفها الكتاب شخصية عنترة بن شداد ، لجمعها بين مجموعة من الثنائيات المتضادة، جعلت منها شخصية كونية صالحة للاستحضار والتوظيف في أي عصر، وفي أي مكان
وتطمح هذه الدراسة الناظرة إلى النصوص الحديثة والمعاصرة المستدعية التراث ، والموظِّفة شخصياته وحوادثه على أنها حاشية على المتن { أي القصة التراثية }، في رصد الاختلاف والاتفاق بين الحاشية والمتن، بالوقوف على مستويات حضور ثوابت المتن ـ التي لا خلاف عليها ـ وغيابها، ودلالات الحضور والغياب ، وغياب المتن وحضور المتخيل، ودلالات هذا الحضور، بالتطبيق على مسرحية "حواء الخالدة " لـ محمود تيمور، معتمدة أشعار عنترة وما يوافقها في كتب سير الأعلام، والسيرة الشعبية مصدراً أساسياً لحياته. مسبوقاً ذلك برأي في حضور التراث، وعنترة بين الحقيقة والأسطورة، كجزء لا تكتمل الدراسة إلا به .
Detection and Quantification of Some Antiepileptic Drugs in Human Plasma using Hydrophilic Interaction Liquid Chromatography- Triple Quadrupole Mass Spectrometry
No full textMastersA fast, sensitive and selective methods for the detection and quantification of Carbamazepine (CBZ) , Vigabatrin (VGB), Phenytoin (PHT) and Lamotrigine (LTG) in plasma are described using high-performance liquid chromatographic separation with Triple Quadrupole Mass Spectrometry (QQQ). Samples were purified using liquid–liquid extraction and separated on a Phenomenex Luna HILIC 3 μ (2× 150 mm) column using 5 μL as volume of injection. The first method determined the CBZ and VGB in plasma using a mobile phase consisting (75:25, v/v) acetonitril/ ammonium formate (5 mM, pH 3.5) at a flow-rate of 0.4 ml/min. Detection was performed by a triple quadrupole model G6410A mass spectrometer in the multiple reaction monitoring mode (MRM) using electro spray ionisation (ESI), monitoring the transition of the protonated molecular ion for CBZ at m/z 237 and VGB at m/z 130 to the predominant ions of m/z 194 and 71, respectively. The mean recovery was 81% for CBZ and 100% for VGB. The calibration curves were linear (r=0.991) over the concentration ranges 250–8000 ng/ml for CBZ and 15-960 ng/ml (r=0.999) for VGB. The limits of detection (LODs) for CBZ and VGB in human plasma were 5.43 ng/ml and 3 ng/mL, respectively. The limits of quantification (LOQs) for both analytes in human plasma were 18.2 ng/ml and 10 ng/ml, respectively. Both intra-and inter-day coefficient of variation (CV % or RSD %) values ranged from 1.79–5.89% at three QC levels (750, 4000 and 6400 ng/ml.) for carbamazepine and 1.145-7.03% at three QC levels (i.e., 45, 480 and 768 ng/ml.) for vigabatrin. The second method determined PHT and LTG in plasma using a mobile phase consisting (97.5:2.5, v/v) acetonitril/ ammonium formate (5 mM, pH 3.5) at a flow-rate of 0.2 ml/min. Detection was performed by a triple quadrupole model G6410A mass spectrometer in the MRM mode for PHT and single ion monitoring mode (SIM) for LTG , monitoring the transition of the deprotonated molecular ion for PHT at m/z 251 to the predominant ions of m/z 102 and protonated molecular ion for LTG at m/z 256. The mean recovery was 90% for PHT and 80% for LTG. The calibration curves were linear over the concentration range 250–1885 ng/mL for PHT (r=0.997) and LTG (r=0.998). The LODs for PHT and LTG in human plasma were 5.17 ng/ml and 0.13 ng/ml, respectively. The LOQs for both analytes in human plasma were 17.24 ng/ml and 0.46 ng/ml, respectively. Both intra- and inter-day CV values ranged from 1.66–8 % at three QC levels (250, 500 and 1250 ng/ml) for PHT and 0.71-3.7 % at three QC levels (250, 500 and 1250 ng/ml) for LTG
Pharmacognostical and Biological Study of Caralluma sinaica Growing in Saudi Arabia
No full textPhDCaralluma sinaica (Decne.) is a succulent edible plant, found in the western (Taif) and south western (Asir) region of Saudi Arabia. The plant is sold in the local market and is reputed to have aphrodisiac, anti-diabetic and anti-cancer activities. The diverse applications of Caralluma plants in folk medicine have prompted the phytochemical and biological investigations of their constituents.
This thesis involved pharmacognostical study of C. sinaica, family Asclepiadaceae, growing in Saudi Arabia. A comprehensive review of past pertinent studies and literature review indicated no previous work concerning the chemical constituents and botanical characters of the species under investigation.
The goals of the thesis were:
1- Preliminary phytochemical and mass spectrometric screening for the total alcoholic extract and different fractions of the investigated plant.
2- Isolation and characterization of the main constituents of the plant.
3- Evaluation of the biological activity of the different extracts, fractions, and some selected pure compounds in certain in vitro assays for cytotoxic, chemopreventive, antiplasmodial, antileishmanial and antitrypanosomal activities.
4- Study of the macro and micro morphological characters of the plant both in entire and powdered forms to facilitate the identification of the plant.
The thesis is composed of an introduction (45 pages) and five other parts. Different results are presented in 26 tables and illustrated by 99 figures. At the end of the thesis a list of 149 references used in the different parts is given.
I. Introduction; included a brief discussion in the taxonomy of Asclepiadaceae, folk uses of different Caralluma species. The phytochemistry of genus Caralluma was discussed with emphasis on pregnane glycosides constituents and their reported biological activities in literature.
II. Experimental; listed all materials, equipment and techniques used in spectroscopic, phyto-chemical, biological and botanical studies.
III. Phytochemical Study of the Aerial Parts of C. sinaica; preliminary phytochemical screening revealed the presence of sterol glycosides and flavonoids. This section included detailed description for extraction and solvent partitioning of C. sinaica. and different chromatographic techniques used to isolate pure metabolites. In addition, it included chromatograms of UPLC-TOF-MS analysis for total alcoholic extract and the different fractions obtained.
IV. Results and Discussion of Isolated Compounds; this section illustrated the methodology used for characterization of all isolated compounds. A total of 16 compounds were isolated and identified from the chloroform, ethyl acetate and n-butanol
extracts based on physical, chemical and spectroscopic techniques, including IR, UV, MS and 1D and 2D NMR (Table A, pages xiv-xvi).
The current literature was scrutinized for the novelty of the isolated compounds and it revealed the following:
i. The pregnane glycosides: 5.7, 12.2, 12.6a1, 12.6a2, 16.9 and 16.13 are new compounds.
ii. The pregnane glycosides: 3.1, 8.6, 12.3, 12.5, 12.6, 12.7 and B.7 were previously isolated from different Caralluma species.
iii. The flavone aglycone (luteolin) and the flavonol glycoside (rutin) are reported for the first time from genus Caralluma.
iv. The flavone glycoside (luteolin 4`-O-£]-D-neohesperidoside) was previously isolated from several species of Caralluma.
V. Pharmacological Study; included the cytotoxicity and cancer chemoprotective potential in vitro bioassays performed for total alcoholic extract of the plant, different fractions and some of the isolated compounds. Compounds 3.1 and 8.6 demonstrated the highest cytotoxicity and QR induction activity with CD values of 5.8 and 6.5 ƒÝg/ml, respectively. In addition, In vitro antiplasmodial, antileishmanial and antitrypanosomal activities were determined for the different extracts by In vitro assays and indicated that the chloroformic extract is active against L. infantum and P. falciparum (K1) with IC50 9.41 and 8.23 £gg/ml, respectively.
VI. Botanical study; represented the macroscopical and microscopical characters of different organs of the plant (old stem, young stem, root and modified leaf) as well as the microscopical features of the powdered plant organs
Increasing the Performance of Iris Recognition System Using Image Processing Techniques
No full textNewly, iris recognition system plays an important role in safety and
protection of environments which need high security measures. The system
starts by capturing an image from an individual's eye. Then, the iris is
localized and normalized for feature encoding process. The performance of
iris recognition system highly depends on the iris localization stage. Feature
encoding stage wouldn’t be able to encode useful information from an iris
image if the iris wasn’t segmented properly. The contribution of our thesis is
to enhance the performance of iris recognition system by enhancing the iris
localization stage. Iris localization or segmentation stage depends mainly on
the pupil detection step. However, due to the nature of eye imaging, the
images always suffer from poor quality caused by noises, reflections, low
contrast, blurred edge and shadow effect. It takes considerable efforts for
pupil detection in order to localize the boundaries of iris and the manual
localization is not reproducible.
The most previous iris segmentation or localization algorithms failed to
detect pupil in presence of variations and reflections in pupil which will be
lead to fail the iris localization. So, the iris recognition system will be
inefficient and inaccurate. To enhance the accuracy of iris localization, a new
approach has been proposed to localize the iris based on pupil detection and
sclera detection. Pupil detection has been done by using a region growing
algorithm. Region growing algorithm needs a seed point. The seed point can
be selected by dividing the eye image into nine sub-images and finding the
mean of minimum pixel intensity values for each sub-image. Sclera detection
has been done by using a global thresholding method, morphological
operations, and simple rules. The approach was able to localize the iris with
high accuracy results and reduce time execution. We also proposed a novel
iris noise detection approach based on a multi-stage 2D entropy
segmentation technique. The experimental results demonstrate that the two
proposed approaches perform better than the previous methods
Synthesis and Biological Evaluation of Some New Thiazolodiazepine Analogues as CNS Active Agents
No full textPhDThe ultra‐short ac ng ac vity of ethyl 8‐oxo‐5,6,7,8‐tetrahydro‐thiazolo[3,2‐a]
[1,3]diazepin‐3‐carboxylate (HIE‐124, 12), as a member of a novel class, which might overcome
many of the disadvantages and problems that usually associated the use of thiopental or
benzodiazepines as intravenous anesthetic agents has been reported.
The present investigation is directed toward the synthesis of new derivatives of the
parent thiazolo[3,2‐a][1,3]diazepine (HIE‐124, 12), in continuation to the previous patented
efforts in this area. These derivatives possess the potential to exhibit a promising and varying
range of CNS activities, including, among others, hypnotic and anticonvulsant activities.
The proposed compounds were synthesized according to the designed strategy.
Structure elucidation of the synthesized intermediates and final products was attained by the
aid of IR, 1H, 13C NMR, and mass spectrometry. The synthesized compounds were evaluated for
various CNS activities.
The new analogues Ethyl 3‐methyl‐8‐oxo‐5,6,7,8‐tetrahydro‐thiazolo[3,2‐a]
[1,3]diazepine‐2‐carboxylate (35) and 2‐Bromo‐3‐methyl‐6,7‐dihydro‐thiazolo[3,2‐a]
[1,3]diazepin‐8(5H)‐one (40) showed marginal hypnotic potency compared to what was
reported about the parent compound HIE‐124 (12).
Biological screening results allowed the allocation of two potent anticonvulsant agents
worth patency. Compounds 35 and 40 proved to be the most active compounds in the present
inves ga on as an convulsants with remarkable 100% protec on against PTZ induced
convulsions as compared with the standard drug valproic acid. It is worth mentioning that
compounds 35 (0.78 mmole/kg) and 40 (0.39 mmole/kg) proved to be almost two and four fold
more ac ve, respec vely; than the used posi ve control sodium valproate (1.38 mmole/kg).
Structure activity correlation of the obtained results revealed that, CNS activity is
embedded in the structure core (8‐oxo‐5,6,7,8‐tetrahydro‐thiazolo[3,2‐a][1,3]diazepine) of the
investigated compounds. Structure activity relationships (SAR) were deduced from the obtained
data.
These studied 8‐oxo‐5,6,7,8‐tetrahydro‐thiazolo[3,2‐a][1,3]diazepine analogues could be
considered as useful templates for future development and further derivatization or
modification to obtain more potent CNS active compounds
Wole Soyinka‘s Drama: A Model of Cultural Representation
No full textThis study examines the dramaturgy of the Nigerian Nobel Laureate, Wole Soyinka as a model of an authentic discourse of cultural representation. It has four parts: the first part illustrates the epistemological background of the issue of representation in general, and the representation of the African identity in particular. The second part examines Soyinka’s writings as a system based on his theory of "self-apprehension," and therefore, asserts its reliability and credibility as an authentic system of cultural representation. The third part delves into the technical details of Soyinka’s dramaturgy as his chosen milieu for presenting his culture. Finally, the fourth part analyzes the components of Soyinka’s unique concept of tragedy in relation to the relationship between Western and African theatrical arts.
In the introduction, the study discusses the epistemological background of representation in reference to the theories of colonial discourse developed by Edward Said in Orientalism. Then it moves on to examine the 1950s movement of Negritude—established and developed by African intellectuals from the African Diaspora—as a system of representation that was dominated by the colonial discourse of power. Afterwards, the chapter addresses Soyinka’s response to Negritude as the foundation from which he developed his theory of "self-apprehension." From there, the chapter elicits Soyinka’s view of cultural
representation in relation to his proposed theory of "self-apprehension." Finally, as an introductory chapter, it draws a general outline of individual chapters in the dissertation, and their premises regarding the core issue of Soyinka’s drama as a model of cultural representation. The first chapter, which is entitled “A Nigerian Voice,” starts from Soyinka’s theory of "self-apprehension" to discuss the mainstream of his writings. The chapter then comments on the trajectory of Soyinka’s dramaturgy in relation to its linear relationship to his immersion in the socio-political changes in Nigeria. In the second chapter, entitled “A Successful Blend,” the study progresses to examine techniques Soyinka implemented to blend traits from Yoruba theatre with elements from Western theatrical tradition. The purpose of this chapter is to highlight Soyinka’s approach to represent Yoruba culture and theatrical tradition via the milieu of drama. In the third chapter, entitled “Soyinka and the Yoruba Concept of Tragedy,” the study addresses Soyinka’s unique concept of tragedy. Soyinka developed his tragedy from a combination of a Yoruba-oriented essence of the tragic action with a Classical-based frame. The chapter is composed of two parts, the first part synthesizes Soyinka’s theory of tragedy; and the second part examines Soyinka’s play, Death and the King’s Horseman, as a practical manifestation of his theory of tragedy. Finally, the conclusion knits all the threads of the individual chapters, and asserts the main premise of this study on the dramaturgy of Wole Soyinka as a model of an authentic cultural representation
Iterative Algorithms for Radar Signal Processing
No full textIn this paper, we are interested in the application and the evaluation of the performances of adaptive recursive subspace-based algorithms of linear complexity for the suppression of interferences in Space Time Adaptive Processing (STAP), namely PAST and OPAST. To highlight their application in the STAP, we present the reduction of the rank by the principal components (PC) and the SINR metric methods. The simulation results will be presented and the performances of the STAP for a reduced rank will be discussed with a comparative study made between the used methods
Two-Dimensional Signal Adaptive Processing for Airborne Radar
No full textIn static radars, all the ground returns are received with a Doppler frequency almost null. However, in airborne radars, they present a wide spectrum for the Doppler frequencies because of the platform in motion. Space-time adaptive processing (STAP) was introduced to improve the capacity of radars to detect slow moving targets which can be masked by clutter or jammer. In this paper, we present the principles of STAP and we discuss the properties of optimum detector, as well as problems associated with estimating the adaptive weights such as ambiguities and the high computational cost. The performances are evaluated highlighting the influence of radar parameters on the detection of slow targets. To resolve problem of high computational cost of optimal space-time processing, reduced-rank methods are used. And to resolve Doppler ambiguities staggering of PRF is used. The simulation results are presented and the performances of STAP are discussed
A Pilot Study for Evaluating Arabic Websites Using Automated WCAG 2.0 Evaluation Tools
No full textAbstract
Nowadays, automatic WCAG 2.0 evaluation tools are increasing in numbers, however, there is little evidence of whether these tools are able to evaluate Arabic websites and provide reflective recommendations to improve their accessibility. To gain insight into this issue, we conducted a pilot study to evaluate a set of WCAG 2.0 tools and report on their results. We believe that our study is the first study to consider evaluating WCAG 2.0 automated evaluation tools for Arabic websites.King Saud Universit
On the Development of a Web-Based M-Learning System for Dual Screen Handheld Game Consoles.
No full textThis paper presents our experience on the design and development of an M-Learning web-based system for the Nintendo DSi game console. The paper starts by addressing the difficulties that emerged from the lack of resources on design guidelines for dual screen devices also the absence of adequate techniques and methods to support the design decisions. Then it explains how we overcame these challenges by adopting a design decision suitable for the screen requirements of the Nintendo DSi console. Finally, we present the components of our M-Learning system and the results of a preliminary usability evaluation.King Saud Universit