Long-term fructose-enriched diet introduced immediately after weaning does not induce oxidative stress in the rat liver
Journal ArticleIncreased fructose consumption is correlated with the rising prevalence of obesity, metabolic
syndrome, and type 2 diabetes. It is believed that reactive oxygen species contribute to the
development and progression of metabolic disturbances, especially those associated with
insulin resistance. Dietary fructose produces both pro-oxidative and antioxidative effects,
depending upon the experimental conditions, dosage, duration of treatment, and
pathophysiological milieu. The effects of fructose overconsumption on young populations,
which have an increased risk of developing metabolic disorders in adulthood, have not been
fully elucidated.Wehavepreviously shownthat rats subjected toa long-termfructose-enriched
diet immediately after weaning display impaired hepatic insulin sensitivity. In this study, we
tested the hypothesis that long-term fructose consumption induces alterations in the redox
setting of the liver. Starting fromthe 21st day after birth,maleWistar ratsweremaintained for 9
weeks on a standard diet (control) or a fructose-enriched diet that consisted of standard food
and 10%fructose solution instead of drinkingwater. The expression and activity of antioxidant
enzymes aswell as lipid peroxidation and protein damagemarkersweremeasured. The results
showed that a fructose-enriched diet led to an increased expression of mitochondrial
manganese superoxide dismutase but did not affect antioxidant enzymes activity, lipid
peroxidation, thiol content, and the level of protein oxidation. Therefore, our results suggest
that the decrease in hepatic insulin sensitivity that was previously observed in rats that were
kept on the same diet regimemight be attributed to molecular mechanisms other than redox
disbalance. A possible fructose-related micronutrient deficiency should be examined.
- © 2014 Elsevier Inc. All rights reserved.
Alhadi Mohamed Ali Jelban, (09-2014), Serbian national center for biological research: Elsevier, 34
EFFECT OF PYROLYSIS ON SHRINKAGE PROPERTIES OF SU-8 POLYMER
Master ThesisAbstract
SU-8 has drawn a lot of attention during the last decades due to its promising mechanical and electrical properties. Extensive research regarding the mechanical properties of negative photoresists SU-8 has been carried out during the last decades. A lot of effort has been put into developing methods to properly characterize features such as effect of pyrolysis temperature and the pyrolysis time on shrinkage properties and morphology of SU-8. In this work photo patterned SU-8 were fabricated on silicon wafers by spin process for different speed steps (step (1) 250rpm and time 10sec, step (2) 450rpm and time 30sec, step (3) 0rpm and time 5sec), then Soft baked at 95°C for 4min before cooling for 10min. Exposure to ultraviolet (UV) light was necessary to obtain the shape of the mask, increase crosslinking degree in the irradiated areas and stabilizes them against the action of solvents during development step. The density of UV used was 6 mW/cm2 at 365 nm and exposure time was 5min, while the volume of SU-8 developer was 40cm3 at 10min. Samples were cut into 2cmx2cm dimensions. The pyrolysis was carried out in a closed quartz tube furnace in an inert nitrogen gas (N2) flow at 1500 standard cubic centimeters per minute (SCCM) and different parameter of temperature (350oC, 400oC, 450oC and 500oC) and time (10min and 20min). Peeling of the SU-8 occurs due to a poor adhesion of the resist to the substrate, thicker films or faster heating rates during the pyrolysis of SU-8. Increasing pyrolysis parameters (temperature and time) lead to larger vertical and horizontal shrinkage, lower sheet resistivity and roughness. The scanning electron microscope (SEM), atomic force microscopy (AFM) and profilometer were used to examine the shrinkage and roughness of SU-8, in order to gain an understanding of how it can affect the shrinkage properties and determine the optimized pyrolysis conditions.
Waled Ashor Mftah Galy, (08-2014), جامعة برليس الماليزية: University Malaysia Perlise,
Exploitation survey of sea water in agriculture of coastal deserts in Libya
Journal ArticleThis paper examines the possibility of exploitation sea water in the agriculture of coastal deserts in Libya, some of which salt-tolerant plants (Halophyte), especially that used to feed animals, and convert marshes coastal useless life to nature reserves attract many kinds of migratory birds and marine lives after the cultivation of these marshes by type of plants, which grow in saltwater. In other words this paper will present a study of how to use the seawater as a renewable resource for agriculture in Libya and how this will contribute in sustainable development in this sprawling country. The advantage of this resource can be taken to fill up the gap of natural grassland and the growing demand for animal feed which has caused rising prices of livestock and meats, not to mention the tribal conflicts that occur because of the dispute over grasslands. The most significant reasons that force us to exploit the seawater are:(1) Lack of inventory of underground water in the coastal areas and overlapping with seawater in several areas. In contrast, Libya has the longest coastline on the Mediterranean with a length of more than 1,900 kilometers;(2) Fluctuation rate of the amount of rainfall, which has affected negatively on the natural grassland;(3) More than 90% of the country's population in the coastal areas, that causing a large drain of groundwater which already meager in this region, for this reason the government has worked to establish Artificial River project, which delivers water from the south to the northern areas to reduce this problem, and (4) Depletion and degradation of natural grassland is largely due to overgrazing.
Mohamed Nasar, (06-2014), بلغراد، صربيا: International Academy of Ecology and Environmental Sciences (IAEES, 2
Dynamic oxygen-enhanced MRI of cerebrospinal fluid
Journal ArticleOxygen causes an increase in the longitudinal relaxation rate of tissues through its T1-shortening effect owing to its paramagnetic properties. Due to such effects, MRI has been used to study oxygen-related signal intensity changes in various body parts including cerebrospinal fluid (CSF) space. Oxygen enhancement of CSF has been mainly studied using MRI sequences with relatively longer time resolution such as FLAIR, and T1 value calculation. In this study, fifteen healthy volunteers were scanned using fast advanced spin echo MRI sequence with and without inversion recovery pulse in order to dynamically track oxygen enhancement of CSF. We also focused on the differences of oxygen enhancement at sulcal and ventricular CSF. Our results revealed that CSF signal after administration of oxygen shows rapid signal increase in both sulcal CSF and ventricular CSF on both sequences, with statistically significant predominant increase in sulcal CSF compared with ventricular CSF. CSF is traditionally thought to mainly form from the choroid plexus in the ventricles and is absorbed at the arachnoid villi, however, it is also believed that cerebral arterioles contribute to the production and absorption of CSF, and controversy remains in terms of the precise mechanism. Our results demonstrated rapid oxygen enhancement in sulcal CSF, which may suggest inhaled oxygen may diffuse into sulcal CSF space rapidly probably due to the abundance of pial arterioles on the brain sulci.
Taha M Mehemed, (06-2014), PLoS One: Public Library of Science, 9
Visualization of Lenticulostriate Arteries at 3T: Optimization of Slice-selective Off-resonance Sinc Pulse–prepared TOF-MRA and Its Comparison with Flow-sensitive Black-blood MRA
Journal ArticleRationale and Objectives
To optimize visualization of lenticulostriate artery (LSA) by time-of-flight (TOF) magnetic resonance angiography (MRA) with slice-selective off-resonance sinc (SORS) saturation transfer contrast pulses and to compare capability of optimal TOF-MRA and flow-sensitive black-blood (FSBB) MRA to visualize the LSA at 3T.
Materials and Methods
This study was approved by the local ethics committee, and written informed consent was obtained from all the subjects. TOF-MRA was optimized in 20 subjects by comparing SORS pulses of different flip angles: 0, 400°, and 750°. Numbers of LSAs were counted. The optimal TOF-MRA was compared to FSBB-MRA in 21 subjects. Images were evaluated by the numbers and length of visualized LSAs.
Results
LSAs were significantly more visualized in TOF-MRA with SORS pulses of 400° than others (P < .003). When the optimal TOF-MRA was compared to FSBB-MRA, the visualization of LSA using FSBB (mean branch numbers 11.1, 95% confidence interval (CI) 10.0–12.1; mean total length 236 mm, 95% CI 210–263 mm) was significantly better than using TOF (4.7, 95% CI 4.1–5.3; 78 mm, 95% CI 67–89 mm) for both numbers and length of the LSA (P < .0001).
Conclusions
LSA visualization was best with 400° SORS pulses for TOF-MRA but FSBB-MRA was better than TOF-MRA, which indicates its clinical potential to investigate the LSA on a 3T magnetic resonance imaging.
TAHA M Mehemed, (06-2014), Academic Radiology: Elsevier, 21
Acute mercury toxicity modulates cytochrome P450, soluble epoxide hydrolase and their associated arachidonic acid metabolites in C57Bl/6 mouse heart
Journal ArticleMercury exposure is associated with increased risk of cardiovascular disease and profound cardiotoxicity. However, the correlation between Hg(2+)-mediated toxicity and alteration in cardiac cytochrome P450s (Cyp) and their dependent arachidonic acid metabolites has never been investigated. Therefore, we investigated the effect of acute mercury toxicity on the expression of Cyp-epoxygenases and Cyp-ω-hydroxylases and their associated arachidonic acid metabolites in mice hearts. In addition, we examined the expression and activity of soluble epoxide hydrolase (sEH) as a key player in arachidonic acid metabolism pathway. Mercury toxicity was induced by a single intraperitoneal injection (IP) of 2.5 mg/kg of mercuric chloride (HgCl₂). Our results showed that mercury treatment caused a significant induction of the cardiac hypertrophy markers, atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP); in addition to Cyp1a1, Cyp1b1, Cyp2b9, Cyp2b10, Cyp2b19, Cyp2c29, Cyp2c38, Cyp4a10, Cyp4a12, Cyp4a14, Cyp4f13, Cyp4f15, Cyp4f16 and Cyp4f18 gene expression. Moreover, Hg(2+) significantly increased sEH protein expression and activity levels in hearts of mercury-treated mice, with a consequent decrease in 14,15-, and 11,12-epoxyeicosatrienoic acids (EETs) levels. Whereas the formation of 14,15-, 11,12-, 8,9-dihydroxyeicosatrienoic acids (DHETs) was significantly increased. In conclusion, acute Hg(2+) toxicity modulates the expression of several Cyp and sEH enzymes with a consequent decrease in the cardioprotective EETs which could represent a novel mechanism by which mercury causes progressive cardiotoxicity. Furthermore, inhibiting sEH might represent a novel therapeutic approach to prevent Hg(2+)-induced hypertrophy.
Issa Emhemmed Alemyani Amara, (04-2014), Toxicology Letters: Elsevier, 219
"واقع إدارة التغير وواقع تطبيقاتها لدى رؤساء أقسام كلية التربية قصر بن غشير من وجهة نظر أعضاء هيئة التدريس"- جامعة الطفيلة التقنية- الأردن/ المؤتمر التربوي الدولي السادس بالاشتراك مع جامعة (Bridgewater State University (BSU),USA)- نحو سياسات تربوية فاعلة
مقال في مؤتمر علميهدف البحث إلى التعرف على واقع إدارة التغيير لدى رؤساء أقسام كلية التربية قصر بن غشير جامعة طرابلس من وجهة نظر أعضاء هيئة التدريس. وتقديم مقترحات لتطوير أداء رؤساء أقسام كلية التربية قصر بن غشير جامعة طرابلس في ظل إدارة التغيير. واتبع البحث المنهج الوصفي التحليلي للتعرف على واقع إدارة التغير من خلال تطبيق أداة البحث على مجتمع البحث، وتم الإجابة على أسئلة البحث من خلال إعداد وتصميم الأداة، لمحاولة تحقيق أهداف البحث والوصول إلى النتائج، وتم اختيار عينة عشوائية بسيطة من أعضاء هيئة التدريس بكلية التربية قصر بن غشير والبالغ عددهم ( 22 ) عضو هيئة تدريس وبنسبة (% 20) من مجتمع البحث.
وكانت أهم النتائج:
-1 العبارة التي تنص على أن رئيس القسم ) يتصف بالمرونة الإدارية لتحقيق التغيير المطلوب(، بمتوسط مرجح (4.05) وبنسبة (78%) والتي تتوافق مع مدخل التغيير وفق كيفية إدخال التغيير بشكل عام، وكان الرأي السائد من خلال استجابات أفراد العينة بأنها )مهمة(.
2- حازت العبارتان التي تنصان على )يشترك رئيس القسم مع أعضاء هيئة التدريس في وضع رؤية مشتركة للقسم، يتسم بقدرته على إدارة النزااع وحل الصراع داخل القسم( على نفس الاستجابات من عينة البحث، بمتوسط مرجح (3.95) وبنسبة )74%)، حيث تتوافق مع مدخل المشاركة في صنع القرار، المدخل الإنساني، ويرى الباحثان بإيجابية هذا الجانب في إدارة التغيير، وكان الرأي السارد من خلال استجابات أفراد العينة بأنها )مهمة(.
-3 كانت العبارة التي تنص على ) يراعي أهداف القسم وأولوياته أثناء اتخاذ القرارات المتعلقة بالتغيير(، بمتوسط مرجح (3.85) وبنسبة (71%) والتي تتوافق مع المدخل الوظيفي لإدارة التغيير، وكان الرأي السارد من خلال استجابات أفراد العينة بأنها )مهمة(.
-4 تحصلت العبارات التي تنص على )يحفزا أعضاء هيئة التدريس على إتقان العمل لإحداث التغيير، يحفزا أعضاء هيئة التدريس على إعداد البحوث الإجرائية والدراسات التربوية، يشُرك أعضاء هيئة التدريس في جميع مراحل التغيير تخطيطًا) على نفس الاستجابات من عينة البحث بمتوسط مرجح3.6 ) ) وبنسبة (65%) حيث تتوافق مع المدخل الهيكلي ومدخل المشاركة في إدارة التغيير، وكان الرأي السارد من خلال استجابات أفراد العينة بأنها )مهمة(.
سهيل كامل عبد الفتاح كلاب، أمال عبد الله البوسيفي، (04-2014)، جامعة الطفيلة التقنية الأردن: تم اختياره، 6
"التعلم متعدد المداخل استراتيجية مبتكرة نحو تقنيات أكثر فاعلية في التعليم"- جامعة الطفيلة التقنية- الأردن/ المؤتمر التربوي الدولي السادس بالاشتراك مع جامعة (Bridgewater State University (BSU),USA)- نحو سياسات تربوية فاعلة في مخرجات التعليم في عالم متطور ف
مقال في مؤتمر علميهدف البحث إلى تسليط الضوء على إستراتيجية حديثة، تختلف عن الطرق التقليدية المعتادة في التدريس دون تركها ، والاهتمام بمداخل أخرى تعتمد على دمجها مع أساليب حديثة تتأسس على استخدام مستحدثات تكنولوجيا المعلومات والاتصالات ، واستخدم الباحث المنهج الوصفي التحليلي من خلال الاطلاع على الأدب المنشور والدراسات السابقة في موضوع البحث وذلك للإجابة على تساؤلاته والوصول إلى مجموعة من التوصيات . وتوصل البحث إلى مجموعة من التوصيات منها:
-1 تبني استخدام التعلم متعدد المداخل لتدريس المقررات الدراسية للمراحل التعليمية المختلفة
-2 تفعيل استخدام الإستراتيجية التدريسية القارمة على التعلم متعدد المداخل من قبل أعضاء هيئة التدريس في مؤسسات التعليم
المختلفة، مما قد يسهم في زيادة تحصيل الطلبة.
-3 عقد دورات خاصة لأعضاء هيئة التدريس باستخدام الإستراتيجيات التدريسية الحديثة للخروج من النمط التقليدي في
التدريس، وتطوير طرق التدريس المستخدمة.
سهيل كامل عبد الفتاح كلاب، (04-2014)، جامعة الطفيلة التقنية الأردن: تم اختياره، 6
Electrical conductivity and dielectric relaxation of 2-(antipyrin-4-ylhydrazono)-2-(4-nitrophenyl)acetonitrile
Journal ArticleThe electrical and dielectric properties of the synthesized 2-(antipyrin-4-ylhydrazono)-2-(4-nitrophenyl)acetonitrile (AHNA) have been studied. The direct and alternating current (DC and AC) conductivities and complex dielectric constant were investigated in temperature range 303–403 K. The AC conductivity and dielectric properties of AHNA were investigated over frequency range 100 Hz–5 MHz. From DC and AC measurements, electrical conduction is found to be a thermally activated process. The frequency-dependent AC conductivity obeys Jonscher's universal power law in which the frequency exponent decreases with increasing temperature. The correlated barrier hopping (CBH) is the predominant model for describing the charge carrier transport in which the electrical parameters are evaluated. The activation energy is found to decrease with increasing frequency. The behaviors of dielectric and dielectric loss are discussed in terms of a polarization mechanism. The dielectric loss shows frequency power law from which the maximum barrier height is determined as 0.19 eV in terms of the Guintini model.
Hagar Hussien Hussien Nawar, (03-2014), Physica B: Condensed Matter: North-Holland, 437
NEW AND ONE POT-SYNTHESIS OF FUNCTIONALLY SUBSTITUTED PYRIDINES FROM ENAMINOKETONES
Journal ArticleSeveral new pyridine derivatives were prepared via reacting the enaminoketones 1a-d with active hydrogen reagents. Reaction of the enaminoketones 1a-c with 4-acetyl-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one 2a yielded the pyridines 3a-c. Condensation of the enaminonitrile 1d with 2b-d or 3-(1,5-dimethyl-3-oxo-2-phenyl-2,3- dihydro-1H-pyrazol-4-yl)-3-oxopropanenitrile 8 give the pyridine derivatives 6a-c and 10 respectivly. Also, (E)-3- (3-(dimethylamino)acryloyl)-2H-chromen-2-one 1a reacted with active methylenes in diethyl 3-oxopentanedioate 12 and 4-methyl-6-oxo-2-thioxo-1,2,5,6-tetrahydropyridine-3-carbonitrile 15 to afford the pyridine derivatives 14 and 16 respectively.
Hagar Hussien Hussien Nawar, (03-2014), GLOBAL JOURNAL OF ENGINEERING SCIENCE AND RESEARCHES: gjesr, 1