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Article
Density Functional Theory Calculations of Thiophene - Phenylene Systems And Their Adducts
Density Functional Theory Calculations of Thiophene - Phenylene Systems And Their Adducts

Authors: A. H. Raheem, عباس حسن رحيم --- H. M. Abduljalil H. M. Abduljalil --- T. A. Hussein طالب عبد الرضا حسين
Journal: Journal of Kufa - physics مجلة الكوفة للفيزياء ISSN: 20775830 Year: 2013 Volume: 5 Issue: 2 Pages: 21-26
Publisher: University of Kufa جامعة الكوفة

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Abstract

Density functional theory was employed to investigate the electronic properties of phynelene and thiophene compounds and their adducts, the interaction between the two structures changes to include six systems. Many important electronic properties were studied in two ways, the vertical energy method and vertical orbital method include the chemical potential, chemical molecular hardness, chemical softness, electrophilic index and polarizability. Full geometry optimization was calculated at the same level of theory. The results showed that the new structures have low chemical hardness with large electrophilicity, and they are more reactive .

Density functional theory was employed to investigate the electronic properties of phynelene and thiophene compounds and their adducts, the interaction between the two structures changes to include six systems. Many important electronic properties were studied in two ways, the vertical energy method and vertical orbital method include the chemical potential, chemical molecular hardness, chemical softness, electrophilic index and polarizability. Full geometry optimization was calculated at the same level of theory. The results showed that the new structures have low chemical hardness with large electrophilicity, and they are more reactive .


Article
Functional Analysis of ‘’Anticipatory It Lexical Bundles’’in Political Speeches

Author: Sawsan Kareem Zughyyir
Journal: journal of Human Sciences مجلة العلوم الانسانية ISSN: 19922876/25239899 Year: 2011 Volume: 1 Issue: 8( خاص بالمؤتمر) Pages: 362-378
Publisher: Babylon University جامعة بابل

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Abstract

This paper investigates a particular structural group of frequent word combinations referred to as ‘anticipatory it lexical bundles’. Lexical bundles are words formed that often co- occur in longer sequences. They are not idiomatic or structurally complete, but the sequences are building blocks in discourse and are so common and recurrent that the readers and listeners should pay much attention to them. The paper aims at showing and exploring structures and functions of the 'anticipatory it lexical bundles' presented in political speeches. It adopts Hewings and Hewings's categorization of interpersonal functions of 'anticipatory it lexical bundles'. Furthermore, the present investigation scrutinizes the interpersonal functions of 'anticipatory it lexical bundles'


Article
Incidence of Recurrent Nasal Polyposis After Endoscopic Polypectomy

Authors: Harith Fathi Hameed --- Lateef Hussien Alwan --- Safaa Sahib Naji
Journal: Medical Journal of Babylon مجلة بابل الطبية ISSN: 1812156X 23126760 Year: 2016 Volume: 13 Issue: 4 Pages: 801 -809
Publisher: Babylon University جامعة بابل

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Abstract

This a prospective study done to provide reference information about the incidence of recurrent nasal polyposis and associated risk factors among 30 patients operated on by means of Endoscopic Sinus Surgery between Jan. 2012 –Jan 2014. These patients presented in otorhinolaryngology dept. in Hilla General Teaching Hospital presented with symptoms and signs of sinonasal polyposis not responding to medical treatment, the diagnosis confirmed by history taken, clinical examination which involved: anterior and posterior rhinoscopy, flexible and rigid nasoendoscopy, with radiological examinations as plain X-ray films and CT- scan of nose &paranasal sinuses (mainly coronal view) taken to all patients to see middle meatal complex. Then the patients underwent polypectomy by means of Endoscopic Sinus Surgery, after that follow-up done during mean period of 12 months (range 3 months – 24 months) included: regular flexible & rigid nasoendoscopy. In our study we estimated the incidence of recurrent nasal polyposis after Endoscopic Sinus Surgery which was 30% and highlighted the risk factors affected this incidence as: age (mostly affected patients at 4th& 5th decade 66.67%), gender (males more than females 3.5:1), presence of some conditions (allergic rhinitis in 33.33%,allergic fungal sinusitis in 22.22%,childhood asthma in 22.22%, eczema in 11.11%, aspirin intolerance in 11.11%, and Samter's triad in 11.11%), previous nasal surgery(simple polypectomy) in 44.44%, and polyp extension as extensive polyposis in 77.78% .


Article
Theoretical Study of the Ground State Intramolecular Proton Transfer in Cytidines
دراسة نظرية للانتقال الظمني للبروتون في الحالة المستقرة للسايتيدينات

Author: Bahjat A. Saeed بهجت علي سعيد
Journal: Journal of Basrah Researches (Sciences) مجلة ابحاث البصرة ( العلميات) ISSN: 18172695 Year: 2009 Volume: 35 Issue: 3A Pages: 98-104
Publisher: Basrah University جامعة البصرة

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Abstract

Four isomers of 1-methyl-N-methoxycytosine and their mutual interconversion were studied theoretically at the B3LYP level using variety of basis sets and a different number of polarization and diffuse functions. It was found that the imino form of the studied molecule is the most stable form within the tautomeric mixture. Transition state of interconversion were studied at the B3LYP/6-31G(d,p) level of theory . The study has shown the exclusion the possibility of direct proton transfer in the gas phase due to the strain in the four-centered transition state, in which the proton being transferred is forced to come close to the positively charged carbon atom at the opposite corner of the four-membered ring.

تمت في هذا البحث دراسة نظرية لاربعة ايزوميرات للمركب 1- مثيل – ن – هيدروكسي سايتوسين باستخدام نظرية الكثافة الدالية و عند مستويات مختلفة من الدوال الاساسية و باستخدام دوال انتشار و استقطاب مختلفة.لقد بينت الدراسة ان توتومر الايمينو هو الشكل الاكثر استقرارا من بين جميع التوتومرات التي يمكن ان تتواجد بها الجزيئة. لقد درست الحالة الانتقالية للتحول التوتومري باستخدام نظرية الكثافة الدالية و بينت الدراسة استبعاد امكانية حصول انتقال بروتوني مباشر في الحالة الغازية كنتيجة للتوتر العالي في الحالة الانتقالية رباعية الحلقة و التي يجبر فيها البروتون المنتفل للاقتراب من ذرة الكاربون سالبة الشحنة الواقعة عند الزاوية المقابلة من الحلقة الرباعية.


Article
A Study of the electronic structure of CdS Nanocrystals using density functional theory
دراسة التركيب الالكتروني لـبلورات كربيتيت الكادميوم (CdS) النانوية باستخدام نظرية دالة الكثافة

Author: Thekra Kasim ذكرى قاسم عبد الرحيم
Journal: Iraqi Journal of Physics المجلة العراقية للفيزياء ISSN: 20704003 Year: 2014 Volume: 12 Issue: 24 Pages: 25-32
Publisher: Baghdad University جامعة بغداد

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Abstract

Density Functional Theory at the generalized-gradient approximation level coupled with large unit cell method is used to simulate the electronic structure of (II-VI) zinc-blende cadmium sulfide nanocrystals that have dimensions 2-2.5 nm. The calculated properties include lattice constant, conduction and valence bands width, energy of the highest occupied orbital, energy of the lowest unoccupied orbital, energy gap, density of states etc. Results show that lattice constant and energy gap converge to definite values. However, highest occupied orbital, lowest unoccupied orbital fluctuates indefinitely depending on the shape of the nanocrystal.

باستخدام نظرية دوال الكثافة (DFT) مع طريقة (LUC) تمت دراسة التركيب الالكتروني لكبريتيت الكادميوم ذات تركيب الزنك بليند للمجموعة (II-VI) بالابعاد (2-2.5) نانومتر. تضمنت الخواص حساب ثابت الشبيكة، عرض حزمتي التكافؤ والتوصيل، طاقة اعلى مستوى مشغول، طاقة اقل مستوى غير مشغول، فجوة الطاقة ، كثافة المستويات ....الخ. النتائج بينت ان ثابت الشبيكة وفجوة الطاقة تصل الى قيم محددة. بالاضافة الى ذلك كلا من طاقة اعلى مستوى مشغول واقل مستوى مشغول تكون غير محددة تعتمد على شكل البلورة النانوية.


Article
Studies on the morphology of the olfactory organ in the freshwater teleost, Labeo bata (Hamilton).
دراسة مظهرية للعضو السمعي لسمكة المياه العذبة Labeo bata (Hamilton)

Authors: P. Chakrabarti بي. جاكرابارتي --- S.K. Ghosh أس. كي. غوش
Journal: Mesopotamian Journal of Marine Science مجلة وادي الرافدين لعلوم البحار ISSN: 18152058 Year: 2013 Volume: 28 Issue: 2 Pages: 163-174
Publisher: Basrah University جامعة البصرة

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Abstract

Abstract - The structural components of the olfactory apparatus of Labeo bata (Hamilton, 1822) were studied morphologically as well as histologically. The oval shaped olfactory rosette was comprised of 24-26 lamellae of different sizes on each side of the median raphe. Histologically each lamella was composed of two layers of olfactory epithelium separated by narrow central core which made up of loose connective tissues, nerve fibres and blood vessels. The sensory olfactory epithelium contained principally three types of receptor cells: primary, secondary and microvillous cells. The non-sensory epithelium was typified with a series of mucous cells, stratified epithelial cells and mast cells. Basal cells were situated at the base of the epithelium, adjacent to the central core. Various cells on the olfactory epithelium were correlated with their functional consequence of fish concerned.

المستخلص – جرت دراسة التركيب المظهري والنسيجي للجهاز السمعي لسمكةLabeo bata وأتضح أن الشكل البيضوي للزهرة السمعية يتكون من 24 - 26 صفيحة دقيقة مختلفة الاحجام وتقع على جانبي الخط الوسطي. نسيجياً، تتكون كل صفيحة من طبقتين من النسيج الطلائي السمعي يفصلهما طبقة وسطية من نسيج رابط رخو وألياف عصبية وشعيرات دموية. النسيج الطلائي السمعي الحسي يحتوي على ثلاثة أنواع من الخلايا المستقبلة وهي الأولية والثانوية والمايكروفيلوس. أما النسيج الطلائي السمعي غير الحسي فيتكون من سلسلة من الخلايا المخاطية ونسيج طلائي طبقي مع خلايا سارية. الخلايا القاعدية توجد عند أسفل النسيج الطلائي بجوار الطبقة الوسطية. جرى ربط مختلف الخلايا السمعية بالوظيفة التي تقوم بها.


Article
Orthodontic considerations of functional occlusion in Class І normal occlusion

Authors: Doaa B. Al-Nassar دعاء باسل النصار --- Hadeel A. Al-Hashimi
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2015 Volume: 27 Issue: 3 Pages: 130-139
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: The therapeutic goal of orthodontic treatment is to establish ideal occlusion which includes both staticand functional aspects. The objective of this study was to clarify functional occlusal treatment goals by analyzingfunctional occlusion in subjects with established normal occlusion and identify the differences between canineprotected occlusion and group function occlusion.Materials and Methods: The sample consisted of 62 subjects with normal occlusion and with an age range of (18-25years).Functional occlusal contacts during lateral excursion were identified on a fully adjustable articulator, and thenthe samples were classified according to:1) Type of functional occlusion:A) Canine protected occlusion group (canine protected occlusion on both working sides).B) Group function occlusion group (group function occlusion on both working sides).C) Mixed functional occlusion group (canine protected occlusion on one side and group function occlusion on theother side.)2) Working side contact into: Canine protected occlusion (62 sides) and group function occlusion (62 sides). Thendifferent variables were analyzed.Results: Results revealed that vertical canine overlap, position of maxillary canine and 1st molar mesiobuccal cusp tipto the center of opposing embrasure/groove, and arch form analysis had significant difference between groups.Adding to that, some of the maxillary and mandibular teeth were significantly differed between groups in regard tocrown angulation and inclination.Conclusions: It was concluded that the vertical canine overlap, position of maxillary canine and 1st molarmesiobuccal cusp tip to the center of the opposing embrasure/groove, arch form harmony were importantfunctional aspects of orthodontic treatment goals


Article
The outcome of stroke: A six month follow-up study
نتائج السكتة الدماغية: دراسة متابعة لمدة ستة أشهر

Author: Kameran Hassan Ismail
Journal: Zanco Journal of Medical Sciences مجلة زانكو للعلوم الطبية ISSN: 19955588/19955596 Year: 2018 Volume: 22 Issue: 1 Pages: 82-88
Publisher: Hawler Medical Univeristy جامعة هولير الطبية

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Abstract

Background and objective: Stroke is an increasing problem in developing countries and is the principal cause of disability and dependency in the western world. This study aimed to find out the one- and six-month case fatality, dependency and recurrence rates of stroke in Erbil teaching hospitals. Methods: This hospital-based prospective study included 293 stroke patients hospitalized in Erbil teaching hospitals from January 1st, 2015 through December 31st, 2015. Stroke was diagnosed by a consultant internist or neurologist and confirmed by brain CT-scan and/or MRI. Patients were followed-up for six months, then one- and six-month outcomes were measured including case-fatality, dependency and recurrences rates.Results: The one and six month case fatality rates were 28.3% and 37.5%, respectively. The rates in females (33.3%, 42.6%, respectively) were higher than that in males (23.7%, 32.9%, respectively), but there was no significant association between case-fatality rate and gender. A total of 74.3% and 45.4% of patients at one- and six-month were functionally dependent. The majority (88.9%) of diabetic patients were functionally dependent. Also, the one and six month recurrence rates of stroke patients were 15.7% and 23.2%, respectively. For both one and six month post stroke more recurrence occurred from ischemic (16.2%, 14.3%, respectively) than from hemorrhagic (24.5%, 19.5%, respectively) strokes, but there was no significant association between the recurrence and stroke subtype (P = 0.691, P = 0.367, respectively).Conclusion: The reported outcomes are relatively comparable to that reported in other developing countries, although it is still more than the rates of developed countries. Outcome measures can help to give information and develop guidelines for clinical practice and research.


Article
Zinc Metal Ion Affected the Structural Stability of Amyloid-Like Nanofibrils

Author: Zahraa S. Al-Garawi
Journal: Al-Mustansiriyah Journal of Science مجلة علوم المستنصرية ISSN: 1814635X Year: 2018 Volume: 29 Issue: 3 ICSSSA 2018 Conference Issue Pages: 50-62
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Synthetic peptides that self-assemble into well-defined structures with a cross-β arrangement are called amyloid-like fibrils. Amyloids are associated with a list of disorders and neuro-degenerative diseases, such as Alzheimer's and Parkinson`s disease. We previously showed that amyloid-like nanofibrils with a repeating motif “IHIH” were functional fibrils. They were able to bind a metal ion through imidazole moieties and mimic the native carbonic anhydrase enzyme by hydrolysing the CO2 molecule. Thus, these synthetic amyloid fibrils were suggest-ed to be good candidates to moderate and update the modern enzymatic molecules. This study aims to shed a light on the stability of these amyloid nanofibrils over a study period of 25 days, in the presence/absence of a metal ion. The work continued for approximately 7 months in the Biochemistry department, School of Life Sciences at the University of Sussex in the United Kingdom. A set of designed peptides with a repeating motif “IHIH” were ex-plored, based on some structural studies. Short and long peptides with free ends as well as closed ends were investigated. Peptides allowed to self-assemble with and without a metal ion (zinc) were then examined using circular dichroism, fluorimetry and electron microscopy for structural biophysical analysis. Regardless of the metal ion contribution, peptides showed stable secondary structures with a -sheet conformation for the incubation time of 25 days. Their morphologies did not appear to change over time. However, the presence of a zinc ion has an effect on the secondary structure of the mature fibrils. Results indicated that fibrils grown with the zinc ion have a significantly higher propensity to form -sheets secondary structures during incubation time. The presence of a zinc ion also affected the dimensions of the amyloid-like fibrils by the end of the study course, at which point they significantly re-duced. This effect of zinc ion on synthetic amyloid fibrils has not been previously reported. The stabilities of the zinc-nanofibrils point to their potential for use in modifying or updating the enzyme-mimic analytical reactions. The effect of adding zinc on the fibrillation seems to be crucial. Although it apparently improved the -sheet assembly, it affected the width/length of the synthetic amyloids. This effect could be promising toward reducing the generation of amyloid fibrils and ultimately understanding the pathogenesis of Alzheimer disease.

الببتيدات الاصطناعية التي لها قابلية التجمع الذاتي وتكوين هياكل ليفية محددة ذات تركيب  الرباعي تسمى بشبيهات ألاميلويد. يرتبط الاميلويد مع قائمة من الاضطرابات والأمراض العصبية، مثل مرض الزهايمر ومرض باركنسون. وضحت دراستنا السابقة أن ألالياف النانوية شبيهة الأميلويد ذات التعاقب المتكرر IHIH" " كانت الياف وظيفية، اذ أظهرت محاكاة ناجحة للانزيم الطبيعي (carbonic anhydrase) عن طريق تآصر مجاميع الاميدازول في الحامض الاميني الهيستدين مع أيون معدني (الخارصين) وتحليل جزيئة p-nitrophenyl acetate التي طالما عمل الانزيم على تحليلها. اقترحت تلك الدراسة ان هذه الالياف الاصطناعية مرشحات جيدة لتطوير نماذج الجزيئات الأنزيمية الحديثة.تهدف الدراسة الحالية إلى إلقاء الضوء على مدى استقرارية هذه الألياف الاميلويدية النانوية بوجود وعدم وجود ألايون المعدني، إذ استمرالعمل بجمع البيانات مدة ٧ أشهر تقريبا في قسم الكيمياء الحيوية، كلية علوم الحياة في جامعة ساسكس في المملكة المتحدة. تم استكشاف وفحص مجموعة من الببتيدات المصممة على اساس تكرار التعاقب "IHIH" " بناءً على بعض الدراسات البنيوية سابقة، بعض هذه الببتيدات قصيرة السلسلة (٧ احماض امينية) وأخرى طويلة ( ١١ حامض اميني) ، وبعضها ذات نهايات لحرة بينما أخرى كانت ذات نهايات مغلقة، كما تم فحص استقرارية جميع الببتيدات بوجود وعدم وجود الخارصين باستخدام عدة تقنيات فيزياحياتية مثل ثنائي اللون الدائري، وجهاز الفلورة، والمجهر إلالكتروني، اذ جمعت البيانات من كل تقنية ثلاث مرات متعاقبة على الأقل وحُلّلت احصائياً.أظهر معدل النتائج ان لهذه الببتيدات الاصطناعية شكل شبيه الاميلويد مستقر طيلة فترة المتابعة (٢٥ يوماً)، بوجد وعدم وجود الخارصين، ومع ذلك، كان لوجود أيون الخارصين تأثير على البنية الثانوية للألياف الناضجة. أشارت النتائج إلى أن ميل الألياف النامية بوجود أيون الخارصين لتشكيل بنية ثانوية ذات صفائح  يتزايد معنويا بمرور الوقت أكثر من تلك الالياف النامية بعدم وجود الخارصين. ان وجود أيون الخارصين ضمن الياف شبيهات بالأميلويد لفترة طويلة قد أثر على أبعاد هذه الالياف، اذ لوحظ تقلص معنوي في الطول والعرض في نهاية فترة المتابعة، لم تكن مثل هذه التأثيرات قد دُرست وأُدرجت في الادبيات سابقاً. على اساس ما تقدم، يبدو أن إضافة الخارصين كان له تأثير مهم على التفاف الالياف، فعلى الرغم من تكوين تركيب ثانوي ذو صفائح  بشكل جيد ومُحّسن، كان هناك تأثيراً معنوياً في طول وعرض الالياف الاصطناعية، وهنا، قد يكون هذا التأثير واعداَ نحو الحد من توليد الألياف الاميلويدية وفهم مسببات مرض الزهايمر، وبالتالي كيفية علاجه.


Article
Heun Method Using to Solve System of NonLinear Functional Differential Equations
أستخدام طريقة هون لحل منظومة معادلات الدوال التفاضلية غير الخطية

Author: Shymaa Hussain Salih شيماء حسين صالح
Journal: Baghdad Science Journal مجلة بغداد للعلوم ISSN: 20788665 24117986 Year: 2007 Volume: 4 Issue: 4 Pages: 666-669
Publisher: Baghdad University جامعة بغداد

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Abstract

In this paper Heun method has been used to find numerical solution for first order nonlinear functional differential equation. Moreover, this method has been modified in order to treat system of nonlinear functional differential equations .two numerical examples are given for conciliated the results of this method.

في هذا البحث أستخدمت طريقة هون لأيجاد الحلول العددية لمنظومة معادلات الدوال التفاضلية غير الخطية . طريقة هون أدت الى نتائج دقيقة من خلال أعطاء بعض الامثله العددية.

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