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81.
Little data are available on the role of blood rheology in atherosclerosis in hemodialysis (HD) patients. This study sought to assess the relationship between leukocytes conjugated with platelets (leukocyte aggregates [LA]) and atherosclerosis in patients with HD. The present study included 118 patients on HD. As surrogate markers of atherosclerosis, aortic stiffness measured by brachial-ankle pulse wave velocity, and carotid intima-media thickness (IMT) were measured. As an assessment of LA, a method, microchannel array flow analyzer, which makes it possible to directly observe the flow of blood cell elements through the microchannel, was used. We measured a number of LA during 50 μL flow of whole blood through microchannels. In 12 age-matched healthy individuals, a number of LA during 50 μL flow of whole blood was 25.7±5.4, whereas in HD patients it was significantly increased up to 48.2±16.4 (P<0.001). Flow cytometry demonstrated that LA were predominantly monocytes. Leukocyte aggregates were positively associated with plasma levels of fibrinogen (P<0.01), or serum high-sensitive C-reactive protein (P<0.01). Moreover, LA had highly significant associations with brachial-ankle pulse wave velocity (P<0.001) and IMT (P<0.001). In conclusion, we demonstrated hemorheologically that monocyte-platelet conjugates play an important role in aortic stiffness and IMT in HD patients.  相似文献   
82.
The effect of a thermal annealing treatment at various temperatures on the performance of bulk heterojunction photovoltaic cells based on poly[2-methoxy-5-(2′-ethyl-hexyloxy)-p-phenylene vinylene] (MEH-PPV) and buckminsterfullerene (C60) composites was investigated. With the increase in temperature, three stages were observed: from 60 to 120 °C, the photovoltaic performance of the composite devices became better with the rising temperature; from 120 to 180 °C, the photovoltaic performance decreased to a minimum; but, at about 200 °C, a sharp rise occurred, followed by a gradual decline. The obvious red-shift of the photoluminescence (PL) spectra and the new PL peak and shoulder at about 620 and 660 nm, respectively, indicated the formation of molecular aggregation and the lengthened and the ordered conjugated segments. It was suggested that the crystallization of C60 after thermal annealing at 200 °C, which matched the nano-sized ordered domains of MEH-PPV led to a sharp enhancement in photovoltaic performance.  相似文献   
83.
初仁生 《钢铁》2015,50(7):26-31
 利用Aspex Explorer自动扫描电镜对探伤不合格试样中非金属夹杂物CA2和CA6(C为CaO,A为Al2O3)的尺寸、面积、成分、类型及分布等进行全面分析。从非金属夹杂物本身性质、连铸机本身特性和凝固过程非金属夹杂物行为3个方面集中探讨了高熔点钙铝酸盐类非金属夹杂物聚集行为。结果表明:高熔点钙铝酸盐类非金属夹杂物本身聚集能力很强,极易聚集;弧形连铸机拉速慢,铸坯厚度较一般的中厚板薄,凝固较快,使得凝固终点提前,造成在凝固过程中夹杂物在靠近中心处形成容易聚集区,同时上浮的空间和时间减少,加上推动捕捉的作用,使得中心处聚集形成大型非金属夹杂物。  相似文献   
84.
杨立君  丁超  吴蒙 《电子与信息学报》2015,37(12):2808-2814
该文针对无线传感器网络(WSNs)数据聚合与安全目标之间的矛盾,基于隐私同态和聚合消息验证码技术提出一种同时保障数据隐私性与完整性的可恢复数据聚合方案。该方案支持由聚合结果恢复出各感知数据,从而一方面能够验证感知数据和聚合数据的完整性,另一方面能够对原始数据进行任意所需的处理,不受聚合函数类型的限制。安全分析表明该方案不仅支持数据隐私性、完整性,还能够抵抗未授权聚合攻击,聚合节点俘获攻击,且能够在一定范围内检测及定位恶意节点。性能分析表明,该方案相比其他算法在通信和计算开销方面具有显著优势。为了评估方案性能和可行性,基于TinyOS给出了算法的原型实现。实验结果表明,该方案开销较低,对于资源受限的WSNs是高效可行的。  相似文献   
85.
本文以自行设计的适时观察-显微照相装置,对微细粒赤铁矿的异向凝聚过程进行了动态照相,并用图象分析仪测定了凝聚体尺寸,从而更好地揭示了微细粒赤铁矿的异向凝聚过程与凝聚剂浓度、浆体浓度、pH值等之间的关系。  相似文献   
86.
It has been apparent to the authors that a new generation of software writers is attempting to re-invent the wheel so far as the allocation of resources is concerned. This paper is intended to give an outline of the history and development of this field and a review of the basic techniques that have been implemented. In order to assist the general reader to realise some of the reasoning that went into the derivations of these schedulers it is necessary to give a brief history of the commercial packages which were the foundation of this topic. The second part of the paper describes the design of the basic procedures without the frills that accompanied them in the generally available products.  相似文献   
87.
鲁智勇  安成锦  焦波  毕建权  庞训龙 《电子学报》2015,43(12):2449-2454
针对现有群组AHP(Analytic Hierarchy Process)判断矩阵集结算法,偏重于专家权重的选择,而忽略判断矩阵元素之间联系的不足,提出一种基于生成树集结算子的群组AHP判断矩阵集结算法.该算法依据判断矩阵与简单无向图生成树之间的关系,采用生成树集结算子获取完全一致集结矩阵,并利用完全一致集结矩阵和群组关联集结矩阵,综合考虑判断矩阵元素之间的个体一致性和群组关联性,计算获得满足一致性约束和最优相似性的群组集结结果.通过算例分析,说明该算法的可行性与有效性.  相似文献   
88.
马慧芳  邴睿  赵卫中  常亮 《电子学报》2021,49(1):132-139
图聚集技术是在保留原始图的结构和属性信息的同时,将一个大规模图聚集成简洁的小规模图的技术.随着图的规模不断增加使得图数据变得难以查询和存储,而基于距离的查询,例如最短路径查询,非常依赖图的规模大小.本文提出了面向距离查询的属性加权图聚集算法,在保证节点之间结构和属性相似的同时,保护了节点之间的距离,并有效地减小了图规模...  相似文献   
89.
Magnetron-based gas aggregation cluster source (GAS) was used to prepare high-purity CuO (cupric oxide) nanoclusters on top of sputter-deposited thin film of tungsten trioxide (WO3). The material was assembled as a conductometric hydrogen gas sensor and its response was tested and evaluated. It is demonstrated that addition of CuO clusters noticeably enhances the sensitivity of the pure WO3 thin film. With an increasing amount of CuO clusters the sensitivity of CuO/WO3 system rises further. When CuO clusters form a sufficiently thick and compact layer, the resistance response is reversed. Based on the sensorial behavior, conventional and near-ambient pressure X-Ray photoemission spectroscopies, and resistivity measurements, we propose that the sensing mechanism is based on the formation of nano-sized p-n junctions in between p-type CuO and n-type WO3. The advantages of the GAS technique for preparing sensorial and/or catalytically active materials are emphasized.  相似文献   
90.
China's total energy consumption, according to the official data, decreased impressively during 1997–1998 and increased sharply during 2003–2007, which in turn resulted in energy intensity fluctuation. Many literatures explained this “unusual phenomenon” from the perspectives of technical change, economic structure shifting and statistical data quality. They measured aggregate energy in thermal units by using linear summation approaches. In this paper, from the perspectives of heterogeneity and imperfect substitutability among diverse energy types, we further examine China's aggregate energy consumption by using Divisia (Sato-Vartia) approach. The results show that China's aggregate energy consumption and intensity fluctuated slightly less than values calculated by using conventional linear approaches, and the “unusual phenomenon” is partly explained. It also implies that China's energy intensity changes in 2006–2007 are slightly more optimistic than those officially reported, and the official communiqué of provincial energy intensity reduction achievements are partly bias. Some provincial achievement are underestimated or overestimated on some provinces. Our empirical results are also helpful to further research, such as energy–economic modeling, energy price elasticity, and elasticity of substitution among capital–labor–energy–material (KLEM). The difficulties or defects when using Divisia approach are also discussed in this paper.  相似文献   
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