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Effects of slip and heat transfer on the peristaltic flow of a third order fluid
No full textThe present investigation is concerned with the peristaltic flow of an incompressible and magnetohydrodynamicMHD third order fluid in an inclined asymmetric channel. Both thermal and velocity slip conditionshave been taken into account. The channel walls are maintained at different temperatures. Thegoverning differential systems subjected to their boundary conditions have been solved for small Deborahnumber. In the derived solution expressions, the long wavelength and low Reynolds number assumptionsare utilized. Graphical results are presented for the pressure rise, longitudinal velocity andtemperature. Comparison with the previous published work regarding viscous fluid and no-slip case isperformed. Pumping and trapping phenomena are displayed graphically just to examine the variousinteresting aspects of the present work
كيف تكتب بحثا علميا للمرة الأولي في حياتك : مرشد الباحثين المبتدئين .
No full textيقدم هذا الكتاب منهجية البحث العلمي للمبتدئين بلغة مبسطة ومباشرة تناقش مع الطالب او الطالبة المستجدة على لابحث لاعلمي كل مخاوفهما وقلقهما تجاه البدء في بحث او خطة علمي
موقف المنهج السلفي من الغلو والتطرف التعامل مع غير المسلمين (أنموذج)
No full text- إن سلف الأمة والتابعين لهم بإحسان إلى يوم الدين، يرون أن موالاة الكفار تنقسم إلى ولاء مكفر مخرج من الملة؛ وهو تولي الكفار ومحبتهم لدينهم، أو مظاهرتهم ونصرتهم على المسلمين، وولاء غير مخرج من الملة وهو المعاملة الحسنة معهم وعدم إهدار حقوقهم؛ فهم لم يعدوا جميع صور موالاة الكفار كفرًا أكبرًا كالطرف الأول (أهل الغلو والتفريط)، ولم يعدوها جميعها من الأمور غير المكفرة كالطرف الثاني أهل (التفريط والجفاء)؛ فهم وسط بين الطرفين كما أنهم يفرقون بين المداراة والتقية المشروعة وبين المداهنة والتقية المحرمة؛ فلا يلغون المدارة والتقية مطلقًا، ولا يفتحونها على مصراعيها.لعلمهم أن الإسلام لا ينهى عن بر كل من لا يعتدي على المسلمين بدلالة نصوص القرآن والسنة وإجماع سلف الأمة في كثير ، فالبر ثابت للمسلم وغير المسلم.
2- إنه في أثناء الحرب تنقطع العلاقات بين المسلمين والمحاربين بالفعل، أما رعايا الأعداء الذين لا يشتركون في القتال فإن (صلتهم) لا تنقطع وإن قامت أسبابها، ولذلك لا يمنع قيام الحرب وجود مستأمنين يقيمون في الديار الإسلامية ولا يمسون في أموالهم ولا أنفسهم، والمستأمنون هم الذين يقيمون في الديار الإسلامية مدة محدودة بعقد من ولي الأمر للعمل في تجار وتبادل البضائع وغيرها
Lack of association of G779A ZHX-2 gene variant with HbF levels in b-thalassemia major
No full textThe inherited disorders of hemoglobin synthesis are the most common monogenic disorders worldwide. They include thalassemias, hemoglobin variants, and hereditary persistence of fetal hemoglobin. b-thalassemia is the most common monogenic disorder in India. Clinical manifestations of b-thalassemia are extremely variable in severity. The reasons for this heterogeneity are not very well understood. Previous studies have shown that the genetic variants that modulate HbF levels have a very strong impact on ameliorating the clinical phenotype. In the present study, 5570 blood samples from suspected cases were analyzed using HPLC, amplification refractory mutation system-PCR and reverse dot blot techniques. Of 5570 individuals, we found 676 cases of b thalassemia disease. Molecular analysis revealed the presence of different b-thalassemia mutations in the population under study. Patients with b-thalassemia were classified into mild, moderate, and severe according to severity score based on Hb level, age of onset, age at which patients received their first blood transfusion, degree of growth retardation and splenectomy. Patients with b-thalassemia were analyzed for zinc finger and homeoboxes 2 (ZHX2) G779A polymorphism, and the association between ZHX2 gene polymorphism and severity of b-thalassemia was evaluated. We did not find a significant difference in genotypic and allelic frequency of ZHX2 gene between mild and
moderate, mild and severe, and moderate and severe cases. There was no significant difference in high and low percentage of HbF in GG, GA, and AA bearing individuals showing that ZHX2 gene variant has no role in ameliorating the severity of b-thalassemia major in the South Indian population from Andhra Pradesh
Molecular subtyping of multiresistant communityassociated methicillin-resistant Staphylococcus aureus isolates in Riyadh, Saudi Arabia
No full textA total of 550 subjects from the community and 190 subjects from health care-related facilities in Riyadh, Saudi Arabia were evaluated for the prevalence of nasal Staphylococcus aureus colonization and to identify risk factors associated with S. aureus and methicillin-resistant S. aureus (MRSA) colonization. Among the community subjects, 1% had nasal MRSA colonization. Subjects from health care-related facilities had a lower S. aureus colonization rate (4.2%) than community subjects (1.2%), but had a significantly higher rate of colonization with MRSA (1.65%). Age (P < 0.001) was a significant risk factor for S. aureus colonization, with subjects under age 21 years or between 52 and 61 years showing higher rates of colonization. Recent gastrointestinal disease (P = 0.010) and hospital admission (P = 0.011) were risk factors for nasal MRSA colonization. Comparison of hospital MRSA isolates with the colonization strains by staphylococcal cassette chromosome mec (SCCmec) gene typing and pulsedfield gel electrophoresis (PFGE) typing revealed that, most MRSA strains carried in the community were SCCmec type IV and that most clinical hospital isolates were type III, while health care facility-related carriage isolates were mainly SCCmec type III and type IV. Two new variant SCCmec types were identified. Six clusters of PFGE patterns were distinguished: two mainly comprised health care facility related MRSA strains, three mainly comprised community MRSA strains and one comprised mixed community and health care facility-related MRSA strains. In conclusion, a high prevalence of MRSA colonization was observed among people with no relationship to the hospital setting. The high level of multiple-drug resistance among community MRSA strains in association with the previously reported excessive use of antibiotics highlights the importance of the problem of antibiotic selective pressure. Our results indicate that, both the colonial spread of MRSA and the transmission of hospital isolates contribute to the high MRSA in the communit
Development of Recombinant Yeast and Bacterial Clones for the Production of Human Interferon Gamma
No full textMastersIn the light of modern therapeutic treatment, biodrugs are becoming the cornerstone in treatment of many diseases. This stems from the fact that a classical drug (chemical drugs) treats the symptom of the disease, while biodrugs interfere with the pathway of the disease. The pharmaceutical industry faces the challenges of supplying high amounts of high quality biodrugs, higher production efficiencies will consequently, lower the costs of the final product (Ronald, 2008).
A variety of strategies are being use to optimize the production yield by using recombinant protein production systems, such as Escherichia coli (E. coli) and yeast Saccharomyces cervisiae (S.cervisiae) and Pichia pastoris (P.pastoris) (Schmidt, 2004). Such strategies can be applied early in the development phase and involve the use of genetic engineering and molecular biology techniques, as well as in latter development stages that involve approaches such as high cell density (HCD)
cultivation, optimization of the culture environment, fermentation process engineering and downstream processing phase.
Interferon gamma (IFNγ) is one of these drugs. It is used to treat cancer and immunological disorders. In this work our main objective was to generate yeast and E. coli clones that produced recombinant human IFNγ (rhIFNγ). We used a genetic engineering approach to develop a P.pastoris clone that expresses a rhIFNγ from a wild type cDNA. Similarly we have developed a P.pastoris clone that expresses a rhIFNγ from a synthetic cDNA whose sequence was optimized according to the yeast codon-usage bias. Followed by the analytical production and purification of rhIFNγ from the two clones and controlled the recombinant protein on SDS-PAGE. Followed by identification by Western blot technique. Finally we compared the rhIFNγ production yield of the two clones.
We have also expressed rhIFNγ wild type cDNA in the E. coli origami strain as a soluble Glutathione S-transferase (GST) fusion protein. The expression was induced by Isopropyl-β-D.thiogalactopyranoside (IPTG) and the recombinant protein was controlled by SDS-PAGE and Western blot. This is the first instance of a successful production of rhIFNγ as a soluble recombinant protein in the E. coli expression system
Investigation of the Mechanisms of the Silk Intrauterine Contraceptive Device in Rats.
No full textMastersThe most widely used and studied Female contraceptive methods are the oral
contraceptives and Intrauterine Devices (IUDs). One of the IUDs proposed
mechanisms for inhibition of conception is the induction of local endometrial
inflammations resulting in inhibition of the implantation of the blastocysts. The exact
mechanism of action of IUDs remains incompletely characterized. It is hoped that the
identification of the actual mediator or mediators involved may pave the way for the
introduction of a simple local contraceptive vaginal or uterine gel or pessary with the
hopeful freedom from the reported IUDs- induced side effects.
IUDs induce chemotaxis of neutrophils and macrophages, lymphocytes and
mast cells and that a correlation exists between the accumulation of these cells and the
contraceptive action of the IUDs which may depend upon the release of one or more
of the mediators released by these cells. Thus, the aim of this investigation is to
investigate the possible involvement of the released mediators in the mechanisms of
silk suture IUD. This was approached via the use of some mediators inhibitors and the
measurement of the uterine levels of some of them using ELISA kits.
To execute such aims, female Wistar albino rats were fitted with silk sutures
into one uterine horn and the contralateral horn of each rat was used as a control. The
animals were mated and treatment with the mediators inhibitors started on day 1 till
day 6 of pregnancy. All drugs were injected (I.P). The drugs used were
Hydrocortisone (10mg/kg), Cyclosporine (10mg/kg), Dexamethasone
(2mg/kg), Pyrrolidine dithiocarbamate (100mg/kg) and Celecoxib (10mg/kg). The
animals were killed on day 10 of pregnancy. The influence of the different treatments
on the outcome of pregnancy in both of the IUD-carrying and the contralateral uterine
horns was evaluated. In separate experiments, the levels of the mediators PGE2,
LTB4, TNFα, IL-1α and IFN-γ were quantified in the endometrial scrapings of both
uterine horns using ELISA technique and the specific kits.
Insertion of the silk suture on one uterine horn completely inhibited pregnancy
in the horn carrying the silk suture in 36 rats. Treatment of pregnant rats pre-fitted
unilaterally with silk suture (IUD) from day 1 to day 6 of pregnancy with
hydrocortisone, cyclosporine, dexamethasone, celecoxib, pyrrolidine dithiocarbamate
or with the combination (Hydrocortisone + Cyclosporine + Celecoxib + pyrrolidine)
reduced the % on successful pregnancy in the control uterine horns by 22.2±14.7 to
63.85±14%, The inhibitions with dexamethasone , celecoxib and cyclosporine were
significant. None of the tested drugs induced significant reversal of the IUD-induced
inhibitions. Measurement of the endometrial mediators on late day 5 of pregnancy,
revealed the presence of PGE2, LTB4, TNFα, IL-1α and IFN-γ in both uterine horn.
The presence of the silk suture significantly decreased the endometrial levels of PGE2,
and IFNγ and elevated the level of IL-1α.
The mediator inhibitors used in this study seemed to mimic the silk suture
IUD in inhibiting pregnancy. It is suggested that the mechanisms of action of the
intrauterine silk suture induced inhibition of pregnancy probably resides in its ability
to inhibit synthesis and release of PGE2 and IFN-γ with the additional effect of
elevating the uterine level of IL-1α.
It can be suggested that a combination of dexamethasone that inhibits the
synthesis of both PGE2 and IFN-γ together with a lipopolysaccharide with the ability
to release IL-1α if formulated in an intrauterine tablet with slow release or formulated
into a gel to be administered intruterinally on days 14 or 19 to days 21-23 of the
menstrual cycle may prove to be an affective local contraceptive method with
hopefully none or only slight systemic side effects
Performance Evaluation of Novel Queuing and Scheduling Algorithms under Self-Similar Traffic Pattern
No full textThe area of quality of service (QoS) has matured rapidly over the past few years. Today, there are three main frameworks for providing service differentiation and support for sensitive applications, IntServ [1], DiffServ [2] and MPLS [3]. IntServ and DiffServ can be regarded as mechanisms for translations and descriptions of queueing and scheduling disciplines whereas
MPLS represents a more engineering style feat which relies on underlying mechanisms to provide wanted behavior. The three frameworks do have in common that they rely on fundamental techniques for separating traffic classes and treating these classes independently through queueing and scheduling disciplines. The different classes have set boundaries on certain traffic parameters such as average and peak bandwidth and delay and the combination of queueing and scheduling disciplines are engineered to meet these requirements. It is therefore vital to QoS frameworks that modeling of traffic behavior through domains is accurate so that resources can be assigned as accurately as possible.
Thus, the aim of the proposed project is to devise proper mathematical models for traffic and queueing behavior in multi service Internet using self-similar traffic distributions, and to apply them to practical tools for network engineering, planning and management
إشكالية التعريف في المعاجم العربية الحديثة (دراسة تحليلية مقارنة في نماذج مختارة)
No full textدرست في ىذا البحث قضية التعريف في المعاجم العربية الحديثة بوصفها إشكالية
ذات أبعاد متعددة، انطلاقا من وصف واقع التعريفات في نماذج من المعاجم العربية الحديثة،
ثم تسليط الضوء على مختلف جوانب القصور المأخوذة على تعريفات ىذه المعاجم للمداخل
المعجمية، من حيث مدى وفائها بالمتطلبات الدلالية أو تلبيتها لحاجات الفئات المستهدفة
)وعلى ىذين البعدين بنيت فصلَي البحث(، وأخيرًا تقدمت بمجموعة من المقترحات لمعالجة
مختلف جوانب القصور المبيّنة في الفصلين.
أما النماذج التي قامت عليها الدراسة فهي: المعجم الكبير ، والمعجم الوسيط ،
والمعجم الوجيز )كل ىذه الثلاثة صادرة من مجمع اللغة العربية بالقاىرة( ، المعجم العربي
الأساسي )الصادر من المنظمة العربية للتربية و العلوم والثقافة(. وتم ىذا الاختيار بناء على
النقاط الآتية:
حداثة المعاجم الأربعة. فقد تم إصدار كل واحد من النماذج الأربعة خلال القرن
العشرين.
كونها من وضع مؤسسات علمية لها اعتبار كبير في مجال تطوير الدراسات
اللغوية العربية بصفة عامة، والصناعة المعجمية بصفة خاصة.
تنوّع جماىيرىا واختلاف أىدافها ؛ فالأول موسوعي، والثاني لغوي عام
)ويستهدف كل واحد منهما فئة المثقفين(، والثالث موجو إلى فئة المتعلمين من
أبناء العرب، بينما استهدف الرابع فئة المتعلمين من غير أبناء العرب.
وسرت في دراسة ىذه النماذج على المنهج التحليلي المقارن
Tumour infiltrating CD25+ FoxP3+ regulatory T cells (Tregs) relate to tumour grade and stromal inflammation in oral squamous cell carcinoma
No full textThis research is aimed to quantitate and characterize the subtypes of tumour infiltrating lymphocytes (TILs), in particular the presence of FoxP3+ Tregs in different grades of oral squamous cell carcinoma using monospecific antibody staining of formalin-fixed, paraffin-embedded tissue sections. The correlation between tumour grade and the intensity of tumour infiltrating lymphocytes was tried to be tested, to assume a putative linkage between them. Thirty-four cases of histologically proven primary oral squamous cell carcinoma (OSCC) of different grades of differentiation were assorted to groups 1–3. Three-micron sections of tissue were cut and captured on electrically charged slides (Vision BioSystem, Mount Waverley, Australia) and stained using monospecific antibody against FoxP3+ Treg phenotype (dilution 1:40, Mouse monoclone No: 236A/E7, Ab 20034, IgG1; Abcam, Cambridge, UK). Automated protocols were employed for staining and scoring of staining intensity using Bond™ system (Vision BioSystem). Significant difference in staining intensities (Tregs) was noted among the histologic grades of tumour, where well-differentiated OSCC had significantly low expression of FoxP3+ Tregs in comparison with moderately and poorly differentiated tumours. A significant linear correlation was established between tumour grade and the intensity of TILs, where high grade tumours (poor differentiation) were more markedly infiltrated. There was also a significant positive correlation between FoxP3+ Tregs and TILs in cases studied. The correlation of these three variables noted in the study (FoxP3+ Tregs, tumour grade and TILs) and their significance in a meta-analysis may prove useful in targeting patients with high-risk neoplasms for more aggressive treatment protocols and management strategies.1600-071