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111.
Dystrophic neurites are major components of neuritic (both immature and mature) senile plaques in Alzheimer disease. Previous studies have shown strong immunoreactivity for different neuropeptides, and chromogranin A, a protein associated with dense-core vesicles, in dystrophic neurites. In the present study, antibodies to synaptophysin, synapsin, Rab3a and synaptotagmin (synaptic vesicle proteins), and SNAP-25 (synaptosomal-associated protein of 25 kD) and syntaxin (presynaptic plasma membrane proteins) have been used to learn about the dystrophic neurite equipment of proteins that are necessary for the docking and fusion of synaptic vesicles, and then for exocytosis and neurotransmission. The present results have shown that, although most neuritic senile plaques have chromogranin A- and SNAP-25-immunoreactive dystrophic neurites, only a percentage of them contain synaptophysin, and a minority contain synaptotagmin and Rab3a. Dystrophic neurites do not contain synapsin and syntaxin. These results show that dystrophic neurites of senile plaques are defective in proteins that control exocytosis and neurotransmission. 相似文献
112.
RC Anton RW Brown M Younes MM Gondo MA Stephenson PT Cagle 《Canadian Metallurgical Quarterly》1997,28(9):1079-1082
The bcl-2 gene product inhibits apoptosis and is thought to participate in oncogenesis. Association of bcl-2 immunopositivity with improved prognosis of non-small cell lung cancers (NSCLC) is controversial. Although two studies have reported better survival in bcl-2-immunopositive NSCLCs, a third series has contradicted this finding. The authors studied a relatively larger case series involving 427 patients for whom detailed information on long-term follow-up was available to determine the prognostic significance of bcl-2 expression. The study included 252 adenocarcinomas (AC), 111 squamous cell carcinomas (SCC), and 64 large cell carcinomas (LC). After antigen retrieval, sections were immunostained using a monoclonal anti-bcl-2 antibody (1:60, Clone 124, Dako) and the avidin-biotin complex technique. Staining was scored as positive or negative and also on a semiquantitative scale as 0, low (<10%), moderate (10% to 75%), or extensive (>75%). Bcl-2 immunoreactivity was correlated with survival using the actuarial survival method, Kaplan-Meier method, and log-rank test and was not associated with statistically significant differences in survival for NSCLCs (P = .5537). Differences in survival remained insignificant even after NSCLCs were stratified for cell type, stage, or grade, singly or in combination. Therefore, using this method, bcl-2 immunopositivity does not appear to act as an independent prognostic indicator in NSCLCs. 相似文献
113.
Reliability-based design optimization (RBDO) aims to find the best compromise between cost reduction and safety assurance. Traditionally, component optimization is defined by minimizing the structural cost under a prescribed reliability target for a single limit state. However, as structural failure is rarely devoted to only one component, the system approach becomes necessary to deal with realistic applications. In this paper, a methodology for system reliability-based design optimization (SRBDO) is proposed. Instead of specifying identical predefined component targets, the method is based on adaptive target reliabilities for structural components. An updating procedure is included in the optimization process to ensure the required system reliability. The proposed method aims to find the best compromise between satisfying the target system reliability and optimizing the component performance. The application to reinforced concrete structures shows the interest of the adaptive target reliabilities as well as the efficiency of the updating procedure. 相似文献
114.
Babak Mirtamizdoust Dariusz C. Bieńko Younes Hanifehpour Edward R. T. Tiekink Veysel T. Yilmaz Pejman Talemi Sang Woo Joo 《Journal of Inorganic and Organometallic Polymers and Materials》2016,26(4):819-828
A novel nano-cauliflower-shaped lead(II) metal–organic coordination polymer, [Pb(μ-2-pinh)N3 H2O]n (1), was synthesized using an ultrasonic method. The nanostructure was characterized by scanning electron microscopy (SEM), X-ray powder diffraction, IR spectroscopy, elemental analysis, and thermal analysis. The compound was structurally characterized by single-crystal X-ray diffraction. The coordination compound takes the form of a zig-zag one-dimensional polymer in solid state. The coordination number of the lead(II) ions is six (PbN4O2) with three nitrogen atoms and one oxygen atom from two linker organic ligands, as well as one oxygen from coordinated water and one nitrogen atom from terminal coordinated azide anion. It has a stereo-chemically active lone electron pair, and the coordination sphere is hemidirected. The zig-zag 1D chains interact with neighbouring chains through weak interactions, creating a 3D supramolecular metal–organic framework. Lead oxide nanoparticles were obtained by thermolysis of the new nano coordination compound at 180 °C with oleic acid as a surfactant. The morphology and size were further studied using SEM. Natural bond orbital analyses demonstrate the electronic properties of the lead centre and other atoms. 相似文献
115.
Younes Hanifehpour Babak Mirtamizdoust Sang Woo Joo 《Journal of Inorganic and Organometallic Polymers and Materials》2012,22(4):916-922
The preparation of micro hexagonal-rods of a new 1D polymeric lead(II) complex containing the Pb2-(μ-N3)2 motif, [Pb(dmp)(N3)2] n (dmp is the abbreviation of 2,9-dimethyl-1,10-phenanthroline) by the sonochemical method is described. The new microcrystal is characterized by scanning electron microscopy, X-ray diffraction (XRD), elemental analyses and infrared spectroscopy. A single crystalline material is obtained by applying a heat gradient applied to a solution of the reagents. The single-crystal XRD analyses show that the coordination number for the Pb(II) ions is six, PbN6, with “stereo-chemically active” electron lone pairs and the coordination sphere being hemidirected. The single-crystal X-ray data show the chains of [Pb(dmp)(N3)2] n interact with each other through the π–π stacking interactions, which create a 3D framework. 相似文献
116.
The influence of the concentration of a commercial photochromic dye, incorporated into as-spun and drawn fibres produced from polyethylene and polypropylene, on their mechanical properties was investigated. As-spun fibres were produced by incorporating a commercial photochromic dye at different concentrations at the extrusion stage of the production process of polypropylene, polyethylene and polyester. The fibres from polypropylene and polyethylene, which showed photochromism when exposed to UV light, were then drawn, and their mechanical properties evaluated and analysed using a factorial experimental design, applying appropriate statistical methods. No further investigation was carried out on the polyester as the dye appeared to degrade at the higher temperatures required for its extrusion, leading to a brown fibre, which was not photochromic. According to the analyses, the most significant parameter influencing the mechanical properties of the as-spun fibres was the polymer type; the effect of the dye concentration was dominated by the significance of the polymer type. The effects of the multi-stage hot-drawing process used to produce the fibres on the mechanical properties of the drawn polypropylene and polyethylene fibres were characterised and statistically modelled. It was found that the dyeing concentration had a negative effect on the tenacity and the modulus of the drawn polypropylene fibres but a positive effect on the tenacity and the modulus of the drawn polyethylene fibres. A dye concentration of 0.2% on mass of polymer had a positive effect on the elongation of the drawn polypropylene and polyethylene fibres, whereas the higher dye concentration of 0.4% had a negative effect on the elongation of both drawn fibres. A new forecasting data source was obtained to optimise the selection of the polymer and the dye concentration and to specify the direction of modification, either increasing or decreasing, the significant process parameters. 相似文献
117.
Khaled ZIZOUNI Leyla FALI Younes SADEK Ismail Khalil BOUSSERHANE 《Frontiers of Structural and Civil Engineering》2019,13(5):1171
Structural safety of building particularly that are intended for exposure to strong earthquake loads are designed and equipped with high technologies of control to ensure as possible as its protection against this brutal load. One of these technologies used in the protection of structures is the semi-active control using a Magneto Rheological Damper device. But this device need an adequate controller with a robust algorithm of current or tension adjustment to operate which is further discussed in the following of this paper. In this study, a neural network controller is proposed to control the MR damper to eliminate vibrations of 3-story scaled structure exposed to Tōhoku 2011 and Boumerdès 2003 earthquakes. The proposed controller is derived from a linear quadratic controller designed to control an MR damper installed in the first floor of the structure. Equipped with a feedback law the proposed control is coupled to a clipped optimal algorithm to adapt the current tension required to the MR damper adjustment. To evaluate the performance control of the proposed design controller, two numerical simulations of the controlled structure and uncontrolled structure are illustrated and compared. 相似文献
118.
Experimental and numerical studies were conducted on the performance and capacity of structured packings for mixture separation with very low separation factor. Different formations and conditions of the innovative structured packing PACK‐2100 with high surface area were studied to evaluate the main characteristics such as dry pressure drop. In addition, numerical simulation was performed to describe the details of the flow structure in these modified structured packings. Three‐dimensional computational fluid dynamics modeling of PACK‐2100 allowed for comparing the pressure drop in both laminar and turbulent flow regime. The obtained experimental and numerical data demonstrate the potential contribution of the packing to high‐efficiency systems with low separation factor. 相似文献
119.
Rasoul Moradi Saeed Mahruz Monfared Younes Amini Abolfazl Dastbaz 《Korean Journal of Chemical Engineering》2016,33(7):2160-2168
Electrospun hybrid membranes were synthesized using electrospinning of Poly (vinylidenefluoride) - titanium tetraisopropoxide (PVDF-TTIP) sol. Asymmetric post-treatment of membrane conducted for deprotonation of titanate and making hydrophilic/hydrophobic dual characteristics. The membranes were characterized by various methods such as wettability, scanning electron microscopy, infrared spectroscopy, X-ray diffraction and liquid entry pressure tests. For evaluating the separation performance, these membranes were applied in the VMD process to treat water heavy metal contaminants. The effects of operating parameters such as flow rate, temperature and membrane properties as porosity, on contaminant removal and producing ultra-pure water have been studied. 相似文献
120.
Phasing genotypes to haplotypes is becoming increasingly important due to its applications in the study of diseases, population and evolutionary genetics, imputation, and so on. Several studies have focused on the development of computational methods that infer haplotype phase from population genotype data. The aim of this study was to compare phasing algorithms implemented in Beagle, Findhap, FImpute, Impute2, and ShapeIt2 software using 50k and 777k (HD) genotyping data. Six scenarios were considered: no-parents, sire-progeny pairs, sire-dam-progeny trios, each with and without pedigree information in Holstein cattle. Algorithms were compared with respect to their phasing accuracy and computational efficiency. In the studied population, Beagle and FImpute were more accurate than other phasing algorithms. Across scenarios, phasing accuracies for Beagle and FImpute were 99.49–99.90% and 99.44–99.99% for 50k, respectively, and 99.90–99.99% and 99.87–99.99% for HD, respectively. Generally, FImpute resulted in higher accuracy when genotypic information of at least one parent was available. In the absence of parental genotypes and pedigree information, Beagle and Impute2 (with double the default number of states) were slightly more accurate than FImpute. Findhap gave high phasing accuracy when parents’ genotypes and pedigree information were available. In terms of computing time, Findhap was the fastest algorithm followed by FImpute. FImpute was 30 to 131, 87 to 786, and 353 to 1,400 times faster across scenarios than Beagle, ShapeIt2, and Impute2, respectively. In summary, FImpute and Beagle were the most accurate phasing algorithms. Moreover, the low computational requirement of FImpute makes it an attractive algorithm for phasing genotypes of large livestock populations. 相似文献