New fluorinated quinazolinone derivatives as anticonvulsant agents

AbstractObjectivesThe aim of the present work was to synthesize some novel fluorinated quinazolinones and to evaluate them for anticonvulsant activity and neurotoxicity.MethodsEight compounds were synthesized. Their anticonvulsant activity was evaluated from maximal electroshock-induced seizures in eight groups of six Swiss mice given the test compounds (100mg/kg intraperitoneally), one control group given 10% DMSO (10ml/kg) and one given the reference compound phenytoin (100mg/kg). Neurotoxicity was evaluated by the rotarod test in eight groups of four Swiss mice given the test compounds (100mg/kg), one given saline (10ml/kg) and one given phenytoin (100mg/kg). The structure–activity relations of the compounds and ClogP correlations were determined to explain the results.ResultsFour compounds showed significant anticonvulsant activity with low neurotoxicity when compared with the reference drug.ConclusionThe newly designed compounds could be useful templates for the design and optimization of more active analogues as anticonvulsant agents with low neurotoxicity

On the origins of antiferromagnetic order in a frustrated spin system at high pressure

In this letter, I would like to complement the discussion on the antiferromagnetic (AFM) order in the model-frustrated quantum magnet SrCu2(BO3)2 at high pressure

Melting and Solidification Study of Indium and Bismuth Nanocrystals Using Reflection High-Energy Electron Diffraction

As technology begins to utilize nanocrystals for many chemical, biological, medical, electrical, and optoelectrical applications, there is a growing need for an understanding of their fundamental properties. The study of melting and solidification of nanocrystals is of interest to fundamental understanding of the effect of reduced size and crystal shape on the solid-liquid phase transition. Melting and solidification of as-deposited and recrystallized indium and bismuth nanocrystals were studied using reflection high-energy electron diffraction (RHEED). The nanocrystals were thermally deposited on highly oriented 002-graphite substrate at different deposition temperatures. The growth dynamics of the nanocrystals was studied using in situ RHEED while the morphology and size distributions were studied using ex situ real image technique (atomic force microscopy (AFM) or scanning electron microscopy (SEM)). RHEED observation during deposition showed that 3D nanocrystals of indium are directly formed from the vapor phase within the investigated temperature range, 300 K up to 25 K below the bulk melting point of indium. On the other hand, bismuth condensed in the form of supercooled liquid droplets at temperatures above its maximum supercooling point, 125 K below the bulk melting point of bismuth. Below the maximum supercooling point, bismuth condensed in the solid phase. Post deposition real images showed that the formed nanocrystals have morphologies and size distributions that depend on the deposition temperature, heat treatment, and the amount of the deposited material. As-deposited nanocrystals are found to have different shapes and sizes, while those recrystallized from melt were formed in similar shapes but different sizes. The change in the RHEED pattern with temperature was used to probe the melting and solidification of the nanocrystals. Melting started early before the bulk melting point and extended over a temperature range that depends on the size distribution of the nanocrystals. Nanocrystals at the lower part of the distribution melt early at lower temperatures. With the increase in temperature, more nanocrystals completely melt with the thickness of the liquid shell on the remaining crystals continuing to grow. Due to size increase after melting, recrystallized bismuth nanocrystals showed a melting range at temperatures higher than that of as-deposited. However, recrystallized indium nanocrystals showed an end melting point nearly equal to that of-the recrystallized ones except for the 1.5-ML film which showed an end melting point ∼10 K higher than that of as-deposited

The Holy Book of Tao and Its Arabic Translations - An Introduction

أهداف البحث: يهدف البحث إلى توجيه النظر إلى الدراسة المباشرة للكتب المقدسة غير الكتابية، بتناول أحد أهم الكتب المقدسة في الصين، وإبراز مركزها الفكري والعقدي في العالم، من خلال رؤية تحليلية لبعض متضمنات "كتاب التاو"، وترجماته العربية، حيث تناوله في دراسات غير أكاديمية أُناس ليسوا مختصين فدرسوه بتحيزات غير موضوعية، وهذه الدراسة تقوم بالتعريف بالكتاب وتقييم تلك الدراسات، ونقل ذلك كله إلى المجال الأكاديمي التخصصي. منهج البحث: يقوم البحث على المنهج الاستقرائي، من حيث تتبع ما يتعلق بالكتاب من ترجمات وشروح بالعربية، ثم المنهج الوصفي الذي يعرِّف بالكتاب، ثم المنهج التحليلي والنقدي المتعلق ببعض قضاياه وما كُتب حوله من دراسات. النتائج: أبرز البحث المكانة الدينية لكتاب "التاو"، وبيان مدى تأثيره في الحقل الديني العالمي، وضرورة توجه أنظار الباحثين إلى مزيد من دراسات حوله، وبيَّن أنَّنا في حاجة أكثر لدراسة ثقافة وأديان وتاريخ الصين؛ لاعتبارات عديدة منها: محاولة البحث في قضية النبوة والأنبياء والرسالات في هذه المنطقة، ثم لكون الصين حضارة كبيرة منافسة للعالم الإسلامي، ولعلنا بفهم هذه اللغة والثقافة والتاريخ والأديان نتمكن من التواصل الديني والحضاري مع هذه الحضارة الصاعدة والمنافسة. أصالة البحث: تظهر أصالة البحث في كونه أول بحث على المستوى الأكاديمي، يتناول هذا النص المقدس مباشرة باللغة العربية، وفي كونه معرِّفًا بكافة ما نُشر عنه بالعربية في السياق غير الأكاديمي. مع دراسة ومناقشة هذه الدراسات.Purpose: This research aims to draw attention to the direct study of nondivine books. The research discusses one of the most important holy books in China and highlights its intellectual and ideological status in the world through analytical insight into some of Book of Tao’s implications and its Arabic translations. This book has been discussed in nonacademic studies by nonspecialist persons, who therefore studied it subjectively. This research identifies the book, evaluates those studies and translates them to the specialized academic arena. Methodology: The research is based on an inductive approach by tracking Arabic translations and explanations of the book; a descriptive approach, which involves reviewing the book; and an analytical and critical approach that examines some of the issues in and studies that have been written about the book. Findings: The research highlights the religious status of the "Book of Tao", the extent of its influence in the international religious field, and the necessity of conducting more studies about it. This research showed that we need further studies on China's culture, religions, and history in many areas, including the issue of prophethood, prophets, and messages in this region. Furthermore, as China is a great civilization competing for dominance in the Islamic world, if we can understand the relevant languages, cultures, history, and religions, we can make religious and civilization outreach more effective in this rising civilization and competition. Originality: The originality of this research comes from many points, such as it is the first academic research to address this holy text directly in Arabic. Moreover, this research reviews, studies, and discusses all of the works in this book in the Arabic language in a nonacademic context

Nanoparticles Decorated on Resin Particles and Their Flame Retardancy Behavior for Polymer Composites

New nanocomposites have been developed by doping of amberlite IR120 resin with spherical TiO2 nanoparticles in the presence of maleate diphosphate. Polystyrene composites of resin, maleate diphosphate, and resin-maleate diphosphate were prepared individually. This is in addition to preparation of polymer nanocomposites of polystyrene-resin doped TiO2 nanoparticles-maleate diphosphate. The flame retardancy and thermal stability properties of these developed polymer composites were evaluated. The inclusion of resin and resin doped nanoparticles improved the fire retardant behavior of polystyrene composites and enhanced their thermal stability. Synergistic behavior between flame retardant, resin, and nanoparticles was detected. The rate of burning of the polymer nanocomposites was recorded as 10.7 mm/min achieving 77% reduction compared to pure polystyrene (46.5 mm/min). The peak heat release rate (PHRR) of the new polymer composites has reduced achieving 46% reduction compared to blank polymer. The morphology and dispersion of nanoparticles on resin and in polymer nanocomposites were characterized using transmission and scanning electron microscopy, respectively. The flame retardancy and thermal properties were evaluated using UL94 flame chamber, cone tests, and thermogravimetric analysis, respectively

PHYTOCHEMICAL CONSTITUENTS OF THE LEAVES OF LEUCAENA LEUCOCEPHALA FROM MALAYSIA

Objective: This study was conducted to identify the phytochemical constituents of Leucaena leucocephala leaf extracts using gas chromatography-mass spectrometry (GC-MS).Methods: Hexane, petroleum ether, chloroform, ethyl acetate and methanol leaves extract of L. leucocephala were analyzed using GC-MS, while the mass spectra of the compounds found in the extract were matched with the National Institute of Standards and Technology (NIST) library.Results: GC-MS analysis of L. leucocephala leaves revealed the presence of 30 compounds and the major chemical constituents were Squalene (41.02%), Phytol (33.80%), 3,7,11,15-Tetramethyl-2-hexadecen-1-ol (30.86%) and 3,7,11-Tridecatrienenitrile, 4,8,12-trimethyl (25.64%). Some of these compounds have been reported to possess various biological activities such as antioxidant, antimicrobial, hepatoprotective, antiparasitic, insecticide, nematicide, pesticide, anti coronary, antiarthritic, antiandrogenic, hypocholesterolemic, cancer preventive, anti-cancer, analgesic, anesthetic, allergenic and etc.Conclusion: The findings of this study indicating that L. leucocephala leaves possess various potent bioactive compounds and is recommended as a plant of phytopharmaceutical importance

Modification of phosphoric acid with polyphenol-rich plant extracts: assessment of bond strength to non-eroded and eroded dentine

This study aimed at developing phosphoric acids modified with different polyphenol-rich plant extracts and to verify their effect on the 24h shear bond strength (SBS) to non-eroded and eroded dentine. In this view, the groups contained experimental phosphoric acid (PA), either plain or modified with polyphenol-rich plant extracts, and a commercially available phosphoric acid was used as positive control. The groups were: 1) LabPA (37% phosphoric acid prepared in the laboratory); 2) PA-GSE (LabPA+2% Grape seed extract); 3) PA-Blueberry (LabPA+2% Blueberry extract); 4) PA-Cranberry (LabPA+2% Cranberry extract); 5) PA-GT (LabPA+2% Green tea extract); 6) CommPA (commercial PA, Kerr Gel Etchant, 37.5% phosphoric acid). For SBS, a total of 192 dentine specimens were prepared from sound extracted permanent human molars, by grounding the teeth until the mid-coronal dentine. All specimens underwent a standard smear layer, half of them were straight restored (non-eroded dentine, n=96) and the other half underwent erosion challenge (eroded dentine, n=96; 10 cycles of 1h exposure to human saliva followed by 5 min immersion in 1% citric acid). Consequently, 96 non-eroded and 96 eroded specimens were etched (15s) with the PAs, according to the experimental groups (n=16 specimens/group) and subjected to an etch-and-rinse adhesive system, followed by standardized restoration with a composite resin. After 24 h incubation in humid chamber, the specimens were subjected to SBS using a universal testing machine. The failure mode of each specimen was determined under a stereomicroscope and described qualitatively. Data was analysed with Q-Q plots, Shapiro-Wilk and Levene’s tests for normality and equality of variances, and General Linear Model (GLM) with SBScalc as outcome variable, and “Acid Group” and “Presence of Erosion” as factors. Both factors individually caused an effect to the outcome (p<0.001), but there was no interaction between the factors (p=0.818). All LabPAs (modified or not with plant extracts) had higher SBS than CommPA, and the presence of extract did not influence the results. Non-eroded dentine had significantly higher SBS than eroded specimens. In conclusion, erosion decreases SBS, and the addition of plant extracts did not influence SBS after 24h of restoration

Novel States in Magnetic Materials under Extreme Conditions: A High Pressure Neutron Scattering Study of the Shastry-Sutherland compound SrCu2(BO3)2

This thesis is at the crossing point of dierent elds: Quantum Magnetism which studies the collective properties of low spin systems, Neutron Scattering a powerful technique that enables to probe the microscopic properties of matter, and High Pressure where the use of ultra hard materials allows discoveries in a previously unexplored range. Combining these, we shall search for novel states in magnetic materials under extreme conditions. The extreme conditions are the quantum spin s=1/2, the low dimensionality, the low temperatures, and the high pressures. The material is the Shastry-Sutherland compound SrCu2(BO3)2, a model quantum magnet which has attracted considerable interest over the last decade