980 resultados para 63-20 µm gU
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综合采集20世纪前、中期全国多种宝贵的土地利用数据,特别是早期的一些土地利用资料,利用聚类分析方法将中国大陆部分省区按土地利用变化差异分为7个区:东北区、华北区、西北及黄土高原区、东南沿海区、西南区、青藏高原区和蒙新区,分别对各区的农林土地利用,即耕地、林地的时空变化进行了分析.结果表明,大部分地区耕地面积有较为明显的增加趋势,20世纪50~60年代,各区的耕地面积增加较多,最大年增长率为2.63%,区域差异较大;20世纪前、中期林地面积以1949年为界,此前总体下降、此后有一定的增加趋势.有林地面积也呈
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The impulse response of wireless channels between the N-t transmit and N-r receive antennas of a MIMO-OFDM system are group approximately sparse (ga-sparse), i.e., NtNt the channels have a small number of significant paths relative to the channel delay spread and the time-lags of the significant paths between transmit and receive antenna pairs coincide. Often, wireless channels are also group approximately cluster-sparse (gac-sparse), i.e., every ga-sparse channel consists of clusters, where a few clusters have all strong components while most clusters have all weak components. In this paper, we cast the problem of estimating the ga-sparse and gac-sparse block-fading and time-varying channels in the sparse Bayesian learning (SBL) framework and propose a bouquet of novel algorithms for pilot-based channel estimation, and joint channel estimation and data detection, in MIMO-OFDM systems. The proposed algorithms are capable of estimating the sparse wireless channels even when the measurement matrix is only partially known. Further, we employ a first-order autoregressive modeling of the temporal variation of the ga-sparse and gac-sparse channels and propose a recursive Kalman filtering and smoothing (KFS) technique for joint channel estimation, tracking, and data detection. We also propose novel, parallel-implementation based, low-complexity techniques for estimating gac-sparse channels. Monte Carlo simulations illustrate the benefit of exploiting the gac-sparse structure in the wireless channel in terms of the mean square error (MSE) and coded bit error rate (BER) performance.
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新外显子的起源是一种重要的增加转录组和蛋白质组多样性的分子机制。 对于新外显子及其父本基因的进化和功能特征方面还有很多重要的问题有待于 解决。本研究首先在全基因组水平上鉴定在人和小鼠中产生的新外显子,随后 对这些外显子及其父本基因作进化和功能上的分析。我们发现新外显子倾向于 位于基因的UTR 区域,尤其是5’ UTR 区域,这表明可能有些新外显子的出现 与基因的表达调控相关。我们还发现,产生新外显子的基因具有较高的组织表 达特异性,其基因功能倾向于细胞调控和与外界环境相互作用。通过对外群中 直系同源基因的分析,我们的结果表明进化速率较高的基因更容易获得新的外 显子,纠正了先前认为的获得新外显子会加速基因进化速率的看法。 我们对哺乳类CDYL 基因家族中产生的新外显子进行了具体的进化分析和 功能研究。我们的结果表明CDYL 基因在哺乳类分化前在原先的基因上游区域 获得了一个新的启动子和三个新的外显子。随后在哺乳动物各个支系的分化中, CDYL 基因在小鼠,狗和人中分别独立的进化出一个新的外显子。同源比对的 结果表明,这些新外显子是通过内含子序列的外显子化这一分子机制产生。近 缘物种间的进化速率的计算结果表明这些新产生的外显子具有快速进化的模 式,并且其快速进化可能是由正选择所驱动。在人中,多种突变包括新外显子 的获得,启动子的改变,选择性剪切的发生使得人的CDYL 基因获得了一种新 的编码更长蛋白质的剪切体。在人Hela 细胞系中的实验表明,新产生的蛋白质 与原有的蛋白质相比都具有显著的转录抑制活性,但新的蛋白质的转录抑制活 性较弱,且两者之间存在相互干扰的关系。这一结果表明通过新外显子的获得 产生的新的蛋白质可以丰富原有的基因表达调控体系,使得生物体的调控网络 更加精确。 嵌合RNA 通常认为是由来源于不同的pre-mRNA 的外显子通过反式剪切连 接在一起形成的。这一现象在包括多种动物和植物中被广泛的报道。我们的研 究首先通过大规模表达序列(ESTs)的搜索,在酵母,果蝇,小鼠和人中鉴定 到了大量的嵌合RNA。这一结果表明形成嵌合RNA 在真核生物中是一种普遍 的生物学过程,是一种重要的增加转录组和蛋白质组的多样性的分子机制。对 嵌合RNA 的序列分析表明,仅有<20%的嵌合RNA 在接合处可以找到典型的剪切位点 GU-AG,可以用经典的反式剪切模型来解释其产生机制。然而有意思的 是,我们在大约一半的嵌合RNA 的供体基因之间找到了短的同源序列,这一发 现使我们提出了一种新的分子机制来解释这些嵌合RNA 的形成,我们称之为 “转录滑动”模型。在酵母我们,我们用实验的方法验证了短同源序列对形成嵌 合RNA 的必要性,有力地支持了我们这一模型。
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A new tri-functional ligand iBu2NCOCH2SOCH2CONiBu2 was prepared and characterized. The coordination chemistry of this ligand with uranyl nitrate was studied with IR, 1H NMR, electrospray mass-spectrometry, thermogravimetry, and elemental analysis. The structure of [UO2(NO3)2(iBu2NCOCH2SOCH2CONiBu2)] was determined by single-crystal X-ray diffraction. The uranium(VI) ion is surrounded by eight oxygens in a hexagonal bipyramidal geometry. Four oxygens from two nitrates and two oxygens from the ligand form a planar hexagon. The ligand is a bidentate chelate, bonding through sulfoxo and one of the carbamoyl groups to uranyl nitrate.
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O estudo pretende identificar características demográficas e epidemiológicas em homens com câncer de próstata, atendidos no Hospital das Clínicas da Faculdade de Medicina de Botucatu/UNESP, entre 01/01/2000 e 31/01/2003. Foram colhidos dados em 78 de 94 prontuários, observando-se escolaridade, uso de tabaco, estado civil, idade, diagnóstico e sintomatologia. Utilizou-se metodologia quantitativa associada à estatística descritiva. Foram encontrados 50% com 1º grau incompleto, 27,39% não tabagistas, 87% casados, 43% entre 64 e 73 anos. Observou-se que 27,58% foram diagnosticados em 2000, sendo 63,20% aposentados e 20,70% com sintoma de jato urinário fraco. Apenas 20% tinham realizado exames preventivos e, desses, 77,90% possuíam 1º grau incompleto. O estudo foi feito nesse hospital por ser considerado de referência terciária da Direção Regional de Saúde de Botucatu -DIR XI¹. da amostra, 80% procuraram o serviço apresentando sintomas, o que leva a crer que ainda haja falta de orientação da população quanto ao câncer de próstata, principalmente quanto à incidência e prevalência relacionadas à idade, como fator de risco. O estudo evidencia subsídios para um melhor direcionamento da assistência a esses pacientes, permitindo um diagnóstico precoce e conseqüente possibilidade de cura, além da melhora na qualidade de vida.
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In the recent years, the wild boar (Sus scrofa) trade has increased in Brazil. The present study aimed to detect Leptospira spp. infection in 308 blood samples from wild boars bred in São Paulo state, Brazil. The microscopic agglutination test (MAT) was performed using 29 serovars. Sixty three (63; 20.45%) animals tested positive against the serovars Hardjo (29/63; 46.0%), Copenhageni (11/63; 17.4%), Pomona (8/63; 12.7%), Pyrogenes (4/63; 6.3%), Wolfii (4/63; 6.3%), Autumnalis (3/63; 4.7%), Icterohaemorraghiae (2/63; 3.1%), and Hardjo-miniswajezak (1/63; 15.8%). These results indicate that captive wild boars were infected with Leptospira spp. and may represent a source of infection to humans and other animals.
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During the retaining wall project in soil reinforced with geogrids and face milling system for segmental blocks is essential to determine the maximum connection resistance between the block and the geogrid. Thus, the aim of this study was to analyze the connection resistance based on ASTM D- 6638-01 between the segmental block model MW of Muros Terrae® company with the geogrids model Fortrac® M 35 / 20x20, Fortrac® M 55 / 30x20, Fortrac® M 80 / 30x20 and Fortrac® M 110 / 30x20 of HUESKER Synthetic GmbH using gravel 1 as a filling material. As a result, the resistance curves were obtained for the four models of geogrids and was described how it fracture. An additional investigation was the average gain connection resistance percentage when it is applied to geogrid a second layer instead of a single layer. The average percentage gains in the connection resistance to the geogrids model Fortrac® M 35 / 20x20, Fortrac® M 55 / 30x20, Fortrac® M 80 / 30x20 and Fortrac® M 110 / 30x20 were, respectively, 63.20 %, 63, 47%, 62.23 % and 51.34 %. Finally, we made a comparative analysis of the results of this study with those obtained by Guimarães (2006), Urashima et. al (2008) and Almeida and Toma (2011) to evaluate which combinations offered higher connection resistance
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In patients with acute cancer-associated thrombosis, current consensus guidelines recommend anticoagulation therapy for an indefinite duration or until the cancer is resolved. Among 1,247 patients with acute venous thromboembolism (VTE) enrolled in the prospective Swiss Venous Thromboembolism Registry (SWIVTER) II from 18 hospitals, 315 (25%) had cancer of whom 179 (57%) had metastatic disease, 159 (50%) ongoing or recent chemotherapy, 83 (26%) prior cancer surgery, and 63 (20%) recurrent VTE. Long-term anticoagulation treatment for >12 months was more often planned in patients with versus without cancer (47% vs. 19%; p<0.001), with recurrent cancer-associated versus first cancer-associated VTE (70% vs. 41%; p<0.001), and with metastatic versus non-metastatic cancer (59% vs. 31%; p<0.001). In patients with cancer, recurrent VTE (OR 3.46; 95%CI 1.83-6.53), metastatic disease (OR 3.04; 95%CI 1.86-4.97), and the absence of an acute infection (OR 3.55; 95%CI 1.65-7.65) were independently associated with the intention to maintain anticoagulation for >12 months. In conclusion, long-term anticoagulation treatment for more than 12 months was planned in less than half of the cancer patients with acute VTE. The low rates of long-term anticoagulation in cancer patients with a first episode of VTE and in patients with non-metastatic cancer require particular attention.
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Understanding past changes in sea surface temperatures (SSTs) is crucial; however, existing proxies for reconstructing past SSTs are hindered by unknown ancient seawater composition (foraminiferal Mg/Ca and d18O), or reflect subsurface temperatures (TEX86) or have a limited applicable temperature range (Uk'37). We examine clumped isotope (D47) thermometry to fossil coccolith-rich material as an SST proxy, as clumped isotopes are independent of original seawater composition and applicable to a wide temperature range and coccolithophores are widespread and dissolution resistant. The D47-derived temperatures from <63, <20, <10 and 2-5 µm size fractions of two equatorial Pacific late Miocene-early Pliocene sediment samples (c1; c2) range between ~18-29 {degree sign}C, with c1 temperatures consistently above c2. Removing the >63 µm fraction removes most non-mixed layer components; however, the D47-derived temperatures display an unexpected slight decreasing trend with decreasing size fraction. This unexpected trend could partly arise because larger coccoliths (5-12 µm) are removed during the size fraction separation process. The c1 and <63 µm c2 D47-derived temperatures are comparable to concurrent Uk'37 SSTs. The <20, <10 and 2-5 µm c2 D47-derived temperatures are consistently cooler than expected. The D47-Uk'37 temperature offset is probably caused by abiotic/diagenetic calcite present in the c2 2-5 µm fraction (~53% by area), which potentially precipitated at bottom water temperatures of ~6 {degree sign}C . Our results indicate that clumped isotopes on coccolith-rich sediment fractions have potential as an SST proxy, particularly in tropical regions, providing that careful investigation of the appropriate size fraction for the region and timescale is undertaken.
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Contient : Ce premier extrait est suivi de la « coppie de tiltres et admortissemens de l'eglise et abbaye N. D. du Pont aux Dames, de l'ordre de Cisteaulx, ou diocese de Meauls en Brye, faicte par l'ordonnance du roy, en l'an 1547 »
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