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1.
In this article, we present the optical design of a novel diagnostic on the HL-2 A tokamak, i.e. the20-channel edge Lyman-alpha beam emission spectroscopy, which is a promising solution for edge density turbulence research on tokamaks, as it offers the possibility of density fluctuation measurement with a 3.3 mm spatial resolution while maintains a high temporal resolution of1 μs. The optical path, including the reflective collection optics, the high-dispersion spectrometer, and the linear detector array, is carefully optimized to obtain a good image quality and a high throughput. The maximum root mean square radius of the collection optics is 64 μm.The detected photon flux is estimated to be about 10~(11) photons/s/channel.  相似文献   
2.
The diagnosis and treatment of prostate cancer (PCa) is a major health-care concern worldwide. This cancer can manifest itself in many distinct forms and the transition from clinically indolent PCa to the more invasive aggressive form remains poorly understood. It is now universally accepted that glycan expression patterns change with the cellular modifications that accompany the onset of tumorigenesis. The aim of this study was to investigate if differential glycosylation patterns could distinguish between indolent, significant, and aggressive PCa. Whole serum N-glycan profiling was carried out on 117 prostate cancer patients’ serum using our automated, high-throughput analysis platform for glycan-profiling which utilizes ultra-performance liquid chromatography (UPLC) to obtain high resolution separation of N-linked glycans released from the serum glycoproteins. We observed increases in hybrid, oligomannose, and biantennary digalactosylated monosialylated glycans (M5A1G1S1, M8, and A2G2S1), bisecting glycans (A2B, A2(6)BG1) and monoantennary glycans (A1), and decreases in triantennary trigalactosylated trisialylated glycans with and without core fucose (A3G3S3 and FA3G3S3) with PCa progression from indolent through significant and aggressive disease. These changes give us an insight into the disease pathogenesis and identify potential biomarkers for monitoring the PCa progression, however these need further confirmation studies.  相似文献   
3.
陕南山地烟田不同植烟年限土壤养分的变化   总被引:1,自引:0,他引:1  
为给陕南山地烟草生产布局及有针对性的施肥措施提供依据,分析了陕南山地烟田不同植烟年限(0~15年)与土壤养分含量的关系。结果表明:随着植烟年限延长,有机质线性下降,全氮和速效钾显著上升,有效磷先上升后下降;氯、有效铁、有效锰、有效硼和有效铜无显著变化或变化很小,有效锌则在第1年急剧下降,之后保持稳定,10年后再次显著下降。认为陕南山地烟区烟叶生产中应适当增加有机肥的施用而合理控制氮肥、磷肥和钾肥的施用,并要注意锌肥的补充。  相似文献   
4.
以二茂铁甲醛和对甲苯磺酰基异氰(TOSMIC)为原料,经过Van Leusen反应,一步合成目标化合物5-二茂铁基噁唑,通过~1HNMR、~(13)CNMR和ESI-MS对其结构进行表征,并对影响收率的主要因素进行考察。结果表明,在物料比n(TOSMIC)∶n(二茂铁甲醛)为1.1∶1、反应溶剂为甲醇、K_2CO_3用量即n(K_2CO_3)∶n(二茂铁甲醛)为2.0∶1、反应温度为65℃、反应时间为8 h的最佳条件下,目标化合物收率达到74.7%。该方法具有原料廉价易得、反应操作简单、收率高等优点,具有一定的应用价值。  相似文献   
5.
14 medicated hypertensive, 15 nonmedicated mild hypertensive, 39 normotensive, and 13 hypotensive adults participated in a 1–2 hr laboratory experiment that assessed each S's symptoms, moods, and estimates of systolic blood pressure (SBP) relative to actual SBP levels. Several self-reports and autonomic measures were collected during and after each of 22 tasks. Within-S correlations indicated that all Ss could estimate SBP at levels greater than chance. Further, 68% of the Ss evidenced at least 1 significant symptom–SBP correlation. Although medicated hypertensives believed they could estimate their BP more accurately than other groups, they were actually no more accurate than the other Ss. They also evidenced far fewer empirically derived symptom–SBP and emotion–SBP correlations than any other group. Overall, blood pressure (BP) beliefs were largely inaccurate. If these erroneous beliefs can be eliminated, Ss may be able to estimate BP fluctuations more accurately. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
For users of an executive information system (EIS), the EIS interface is the system and is crucial to the EIS's success. These guidelines for designing EIS interfaces are based on studies of actual EIS interfaces that meet the unique information needs of executives.  相似文献   
7.
Many current implementations of protocols such as the Transmission Control Protocol/Internet Protocol (TCP/IP) are inefficient because data are often accessed more frequently than necessary. Three techniques that reduce the need for memory bandwidth are proposed. The techniques are copy-on-write, page remapping, and single-copy. Afterburner, a network-independent card that provides the services that are necessary for a single-copy protocol stack, is described. The card has 1 MByte of local buffers and provides a simple interface to a variety of network link adapters, including HIPPI and asynchronous transfer mode (ATM). Afterburner can support transfers to and from the link adapter card at rates up to 1 Gbit/s. An implementation of TCP/IP that uses the features provided by Afterburner to reduce the movement of data to a single copy is discussed. Measurements of the end-to-end performance of Afterburner and the single-copy implementation of TCP/IP are presented  相似文献   
8.
本文提出了一处基于虚拟分割机制的可编程多服务器由器实现结构:PVSMR,并对它的三个层面的主要构成及其关键技术进行了深入研究。PVSMR基于一种有效而灵活的资源虚拟分割算法,它能够提供与多类应用相适应的、灵活的报文处理和转发控制能力。  相似文献   
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