58 research outputs found

    Fabrication and Characterization of Chromium Nanotube Using (AAO) Template

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     في البحث الحالي تم تصنيع Cr Nanotube بعملية الترسيب الكهروكيميائي وذلك بترسيبها على أساس من الألمنيوم المؤنود AAO كذلك تم تشخيص الأنابيب الكروم النانوية بواسطة XRD, SEM/EDS and TEM . وقد تبين من خلال هذه التقنيات إن الأنابيب الكروم النانوية كانت تمتلك نقاوة عالية جدا , ومن خلال تقنية SEM لوحظ نمو منتظم للأنابيب النانوية على مستوى عمودي للـ AAO. وكذلك يتضح ذلك من  خلال تقنية TEM والتي يظهر فيها الأنابيب ذات جدار منفرد single wall  بقطر مقارب إلى 60nm.In the current research, the fabricating of Cr nanotubes was done by electrochemical deposition in anodic aluminum oxide (AAO) as template. Characterization of fabricated Cr nanotubes were a achieved by XRD, SEM/EDS and TEM. These techniques indicated that the deposited chromium nanotubes have high purity within experimental conditions, the peaks in XRD was good agreement with JCPDS cards, SEM images showed the growth of ordered nanotubes in one plane perpendicular to the template (AAO). The purity of fabricating nanotubes was confirmed by EDS analysis, while the produced single walled nanotubes was shown from TEM images with open ends of tubes. 60 nm as diameter was obtained for fabricating Cr nanotubes. The fabrication of Cr nanotubes suggests producing quintuple bonds (Cr ≡ Cr) to form tubes without any chance to deposit chromium as particles

    Electrodeposition of NiCr Nanowires Using Anodic Aluminum Oxide

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     يشير هذا البحث الى تصنيع اسلاك نانوية لسبيكة نيكل-كروم بواسطة الترسيب الكهروكيميائي. انجز الترسيب الكهروكيميائي على اساس من اوكسيد الالمنيوم المؤنود ( AAO ) ذات ثقوب نانوية قطرها ( 70 nm ). تمت عملية الانودة للالمنيوم بأستعمال حامض الاوكزالك وذلك بخطوتين من الانودة للحصول على الاساس AAO ثم تلاها ترسيب سبيكة نيكل-كروم من املاح كبريتات النيكل وكبريتات الكروم وكانت نسب العناصر الناتجة للسبيكة هي 72.3Ni27.7Cr . الاسلاك النانوية الناتجة تم تشخيصها بأستعمال المجهر الالكتروني SEM والمجهر الالكتروني TEM.ان الاسلاك النانوية الناتجة تمتلك قطر بمقدار( 70 nm ) وطول ( 420-500 nm ).This research highlights fabrication of NiCr nanowires by electrochemical deposition. The deposition was achieved using anodic aluminum oxide AAO template with 70 nm diameter of pores. The anodization was performed using oxalic acid with two steps to obtain AAO template. 72.3Ni27.7Cr nanowires were obtained using nickel and chromium sulfate. The nanowires were characterized by SEM and TEM. The obtained nanowires with 70 nm diameter and 420-500 nm length

    Peroxisome proliferator-activated receptor γ1 expression is diminished in human osteoarthritic cartilage and is downregulated by interleukin-1β in articular chondrocytes

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    Peroxisome proliferator-activated receptor γ (PPARγ) is a nuclear receptor involved in the regulation of many cellular processes. We and others have previously shown that PPARγ activators display anti-inflammatory and chondroprotective properties in vitro and improve the clinical course and histopathological features in an experimental animal model of osteoarthritis (OA). However, the expression and regulation of PPARγ expression in cartilage are poorly defined. This study was undertaken to investigate the quantitative expression and distribution of PPARγ in normal and OA cartilage and to evaluate the effect of IL-1β, a prominent cytokine in OA, on PPARγ expression in cultured chondrocytes. Immunohistochemical analysis revealed that the levels of PPARγ protein expression were significantly lower in OA cartilage than in normal cartilage. Using real-time RT-PCR, we demonstrated that PPARγ1 mRNA levels were about 10-fold higher than PPARγ2 mRNA levels, and that only PPARγ1 was differentially expressed: its levels in OA cartilage was 2.4-fold lower than in normal cartilage (p < 0.001). IL-1 treatment of OA chondrocytes downregulated PPARγ1 expression in a dose- and time-dependent manner. This effect probably occurred at the transcriptional level, because IL-1 decreases both PPARγ1 mRNA expression and PPARγ1 promoter activity. TNF-α, IL-17, and prostaglandin E2 (PGE2), which are involved in the pathogenesis of OA, also downregulated PPARγ1 expression. Specific inhibitors of the mitogen-activated protein kinases (MAPKs) p38 (SB203580) and c-Jun N-terminal kinase (SP600125), but not of extracellular signal-regulated kinase (PD98059), prevented IL-1-induced downregulation of PPARγ1 expression. Similarly, inhibitors of NF-κB signaling (pyrrolidine dithiocarbamate, MG-132, and SN-50) abolished the suppressive effect of IL-1. Thus, our study demonstrated that PPARγ1 is downregulated in OA cartilage. The pro-inflammatory cytokine IL-1 may be responsible for this downregulation via a mechanism involving activation of the MAPKs (p38 and JNK) and NF-κB signaling pathways. The IL-1-induced downregulation of PPARγ expression might be a new and additional important process by which IL-1 promotes articular inflammation and cartilage degradation

    Alterations of metabolic activity in human osteoarthritic osteoblasts by lipid peroxidation end product 4-hydroxynonenal

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    4-Hydroxynonenal (HNE), a lipid peroxidation end product, is produced abundantly in osteoarthritic (OA) articular tissues, but its role in bone metabolism is ill-defined. In this study, we tested the hypothesis that alterations in OA osteoblast metabolism are attributed, in part, to increased levels of HNE. Our data showed that HNE/protein adduct levels were higher in OA osteoblasts compared to normal and when OA osteoblasts were treated with H(2)O(2). Investigating osteoblast markers, we found that HNE increased osteocalcin and type I collagen synthesis but inhibited alkaline phosphatase activity. We next examined the effects of HNE on the signaling pathways controlling cyclooxygenase-2 (COX-2) and interleukin-6 (IL-6) expression in view of their putative role in OA pathophysiology. HNE dose-dependently decreased basal and tumour necrosis factor-α (TNF-α)-induced IL-6 expression while inducing COX-2 expression and prostaglandin E(2 )(PGE(2)) release. In a similar pattern, HNE induces changes in osteoblast markers as well as PGE(2 )and IL-6 release in normal osteoblasts. Upon examination of signaling pathways involved in PGE(2 )and IL-6 production, we found that HNE-induced PGE(2 )release was abrogated by SB202190, a p38 mitogen-activated protein kinase (MAPK) inhibitor. Overexpression of p38 MAPK enhanced HNE-induced PGE(2 )release. In this connection, HNE markedly increased the phosphorylation of p38 MAPK, JNK2, and transcription factors (CREB-1, ATF-2) with a concomitant increase in the DNA-binding activity of CRE/ATF. Transfection experiments with a human COX-2 promoter construct revealed that the CRE element (-58/-53 bp) was essential for HNE-induced COX-2 promoter activity. However, HNE inhibited the phosphorylation of IκBα and subsequently the DNA-binding activity of nuclear factor-κB. Overexpression of IKKα increased TNF-α-induced IL-6 production. This induction was inhibited when TNF-α was combined with HNE. These findings suggest that HNE may exert multiple effects on human OA osteoblasts by selective activation of signal transduction pathways and alteration of osteoblastic phenotype expression and pro-inflammatory mediator production

    Association synchrone d’un cancer du sein bilatéral et d’une tumeur stromale gastrointestinale: à propos d’un rare cas

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    Les tumeurs stromales gastro-intestinales sont les tumeurs  mésenchymateuses les plus fréquentes, pourtant, leur association avec les tumeurs du sein sont rares, seulement quelques cas cliniques sont rapportés dans la littérature. Nous rapportons l'observation d'une jeune femme de 41 ans, suivie à l'institut national d'oncologie de Rabat, pour un carcinome canalaire du sein, bilatéral, chez qui le bilan d'extension a objectivé une tumeur stromale de type gastro-intestinale aux dépens de l'estomac. Nous décrivons à travers cette observation les aspects épidémiologiques, cliniques, et les particularités de la prise en charge de cette association rare

    A theoretical review on the preventive measures to landslide disaster occurrences in Penang State, Malaysia

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    Based on the frequently unanticipated occurrences of natural landslide disaster across Malaysia, it can be seen that Malaysia is still not fully prepared for occurrences of natural landslide disaster.The lack of predictive and warning systems for the disaster in the country is creating panic and apprehension among citizens alongside with both economic and property losses. The general objectives of this research are: to identify the meteorological factors that cause landslide natural disaster occurrences in Malaysia and to suggest a predictive model for landslide disaster occurrence in Malaysia. This research therefore explored modelling disasters occurrences in order to predict, warn, and prevent huge impact of landslide disasters in Penang, Malaysia. This research shall make use of past literatures and data from Malaysian Meteorological department considering climatic parameters such as daily mean temperature and daily rainfall only. Data mining and Artificial Neural Networks (ANN) shall be suggested to predict landslide disaster occurrences in Malaysia. Thus, the need for a predictive model for occurrence of landslide natural disaster is imperative to the safety of lives and protection of both environmental and economy of the region

    Online Theme Landscaping Decision Support System

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    The landscape theme has become an important feature for home exterior design. However, selecting a landscape theme based on client preference is difficult due to multiple criteria and budget constraint during the selection process. This paper proposed online decision support systems for selecting landscape theme design that can be use by exterior designer consultant in assisting home owner to make decision within their own budget range. This prototype is constructed using a decision tree as an analysis tool. This online application was developed using PHP as programming language and mySQL as the database platform. This system may not provide the best theme but it will assist the home owner in deciding which one of the design concepts is most suitable according to their needs and preferences

    Leiomyosarcome de la vessie chez une patiente de 64 ans

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    Le leiomyosarcome représente une tumeur rare de la vessie. Sa présentation clinique est non spécifique et dominée par l'hématurie. La résection endoscopique de la vessie avec un examen anathomopathologique permet de poser le diagnostic. La rareté de cette localisation ne permet pas d'établir une stratégie  thérapeutique standard, néanmoins la chirurgie reste le traitement le plus utilisé. Nous rapportons le cas d'une patiente âgée de 64 ans, ayant présenté une hématurie. L'examen anatomopathologique d'une résection endoscopique de la vessie a posé le diagnostic d'un leiomyosarcome.Key words: Sarcome de vessie, leiomyosarcome, tumeur de vessie

    Smart driving simulation using agent approach

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    Road accidents have become a major problem in Malaysia for the last few years.This research focused on minimizing the drivers’ errors by training them to be smart drivers and observe courtesy on the road.New and inexperienced driver can use smart driving system which acts as a simulation of a real driving experience.The multimedia simulation embed with agent will reward the driver with marks based on the actions taken to manage the obstacles along the drive.In conclusion, the system can be used as an alternative training module in familiarizing new drivers with real driving experience
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