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1.
WENXI GAO QIANQIAN MA CHENYU TANG YUELI ZHAN YINONG DUAN HUIHUA NI YUNZHAO XU 《Biocell》2020,44(4):597-605
Cervical cancer (CESC) is one of the most common cancers and affects the female genital tract. Consistent HPV
infection status has been determined to be a vital cause of tumorigenesis. HPV infection may induce changes to the
immune system and limit the host’s immune response. Immunotherapy is therefore essential to improving the overall
survival of both locally advanced and recurrent CESC patients. Using 304 relevant samples from TCGA, we assessed
immune cell function in CESC patients to better understand the status of both tumor micro-environment cells and
immune cells in CESC. Functional enrichment analysis, pathway enrichment analysis, and PPI network construction
were performed to explore the differentially expressed genes (DEGs). The analysis identified 425 DEGs, which
included 295 up-regulated genes and 130 down-regulated genes. We established that upregulation of CCL5 was
correlated with significantly better survival, meaning that CCL5 expression could serve as a novel prognostic
biomarker for CESC patients. We further focused on CCL5 as a hub gene in CESC, as it had significant correlations
with increased numbers of several types of immune cells. Cell-type fractions of M1 macrophages were significantly
higher in the high-immune-scores group, which was associated with better overall survival. Finally, we concluded that
CCL5 is a promising prognostic biomarker for CESC, as well as a novel chemotherapeutic target. 相似文献
2.
Preacher Kristopher J.; Rucker Derek D.; MacCallum Robert C.; Nicewander W. Alan 《Canadian Metallurgical Quarterly》2005,10(2):178
Analysis of continuous variables sometimes proceeds by selecting individuals on the basis of extreme scores of a sample distribution and submitting only those extreme scores to further analysis. This sampling method is known as the extreme groups approach (EGA). EGA is often used to achieve greater statistical power in subsequent hypothesis tests. However, there are several largely unrecognized costs associated with EGA that must be considered. The authors illustrate the effects EGA can have on power, standardized effect size, reliability, model specification, and the interpretability of results. Finally, the authors discuss alternative procedures, as well as possible legitimate uses of EGA. The authors urge researchers, editors, reviewers, and consumers to carefully assess the extent to which EGA is an appropriate tool in their own research and in that of others. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
Bayazit Mahmut; Hammer Tove Helland; Wazeter David L. 《Canadian Metallurgical Quarterly》2004,89(4):738
Methodological problems in studies of union commitment were identified and illustrated with data from 4,641 members and 479 stewards in 297 local teachers' unions. Using a 20-item union commitment scale, results confirmed the existence of 3 substantive factors and 1 method factor at the individual level of analysis: loyalty to the union, responsibility to the union, willingness to work for the union, and a factor of negatively worded items. Tests of measurement invariance showed that the scale captured commitment for rank-and-file members but not for union stewards. The authors also found partial measurement invariance between long-time and newer members and full measurement invariance between men and women. Finally, the authors found that violation of the statistical assumption of independence reduced model fit when individual commitment scores were analyzed without attention to the hierarchical nature of the data. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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绩优问题生,指学业成绩优异、但心理有疾患的大学生。为增强教育的针对性,促进绩优问题生的健康成长和全面发展,本文从家庭、学校、个人三个方面对其进行成因分析,并提出相应教育对策。 相似文献
6.
An effective dual watermark scheme for image tamper detection and recovery is proposed in this paper. In our algorithm, each block in the image contains watermark of other two blocks. That is to say, there are two copies of watermark for each non-overlapping block in the image. Therefore, we maintain two copies of watermark of the whole image and provide second chance for block recovery in case one copy is destroyed. A secret key, which is transmitted along with the watermarked image, and a public chaotic mixing algorithm are used to extract the watermark for tamper recovery. By using our algorithm, a 90% tampered image can be recovered to a dim yet still recognizable condition (PSNR ). Experimental results demonstrate that our algorithm is superior to the compared techniques, especially when the tampered area is large. 相似文献
7.
不确定可再生能源并入电热综合能源系统后将引发系统运行风险,而通过合理量化风险,实现风险可控性和调度经济性平衡是电热综合能源系统风险调度的关键。依据随机风电功率的单峰分布特性构建矩模糊集并以此刻画风电功率的不确定性,同时采用分布鲁棒机会约束方法来刻画系统的运行风险,进而建立了电热综合能源系统的分布鲁棒风险调度模型。在此基础上,从风险发生概率和经济成本的角度,提出了评估不确定风电功率引发运行风险的量化指标:均值风险概率和风险调度成本。最后,以改进的巴厘岛电热综合能源系统为例进行算例分析,验证了所提模型及其风险评估指标的可行性和有效性,并给出了电热综合能源系统的最优调度决策。 相似文献
8.
为充分利用跨区调度资源,提出一种基于分区电价的跨区电力调度双层优化模型。采用等效发电成本曲线对区域内部的煤电机组出力进行建模,采用一种基于整数规划的机会约束方法对风电和光伏出力进行建模。建立与分级调度模式相适应的双层优化模型,作为上级调度机构的上层模型以区域间送受电量为决策变量,以区域间送受电量价值最大化为目标,下层模型实现区域内部的经济调度。根据卡罗需-库恩-塔克(KKT)条件将双层模型转化为单层模型进行求解。算例结果验证了所提模型的有效性。所提模型在送电区域和受电区域之间维持一定的电价差异,通过传输较少的电量缓解受电区域的电力供需矛盾。 相似文献
9.
风光和火电打捆外送是新能源消纳的重要方式,如何确定其容量比成为难题。储能调节灵活,可以平抑新能源出力不确定性造成的影响,但频繁充放电会对电池储能的寿命造成影响。考虑储能的放电深度和循环次数建立了电池寿命量化模型,提出了计及储能寿命的风光火储打捆外送系统双层容量优化模型。上层以系统总成本最小为目标,下层以典型日调度成本最小为目标。利用机会约束处理新能源出力不确定性对系统备用容量的影响,基于序列运算将概率性机会约束转换为确定性约束,将问题转换为易于求解的混合整数线性规划问题。算例结果表明,配置储能可以有效降低系统成本。同时考虑储能寿命可以在保证经济性的前提下制定更合理的调度策略,延长储能使用寿命,验证了模型的有效性。 相似文献
10.
新能源大规模接入电网对电力系统灵活调节能力带来巨大挑战,针对目前电力系统灵活性评估及优化调度集中于供需匹配而缺乏对线路传输能力的考虑,提出了计及线路传输能力的新能源电力系统灵活性评估及优化调度方法。首先,分析线路传输能力对灵活性需求实现的影响,并计及新能源及负荷的波动性和不确定性,量化节点灵活性需求及其在线路上的分配。然后,从资源灵活性裕量和线路灵活性传输裕量两个角度提出系统灵活性不足量评估指标,多方面评估系统灵活性。将该评估指标作为机会约束条件,构建考虑资源-线路双重裕量的优化调度模型。采用线性化手段和基于拉丁超立方抽样的机会约束确定性转化方法将优化调度模型化简为混合整数线性规划模型以降低求解难度。最后,采用改进IEEE39节点系统和某实际电网进行仿真验证,结果表明所提方法能够减轻线路阻塞,减少切负荷量,提高新能源消纳。 相似文献