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991.
民航运输在LTO(Landing and take-off)循环阶段的大气污染物排放对地面人员和近地环境危害较大,应主要通过减少地面滑行时间进行控制。考虑支线机场常见的单跑滑结构给出飞机地面滑行时间计算方法,基于该方法提出了污染物评价指标并建立了支线机场航空器污染物排放评估模型。以某支线机场为例,使用Matlab建模计算得出污染物评价指数最小滑行道口位置。利用AirTOp仿真验证了模型计算结果有效性,优化后的跑道出口位置将使该机场污染物总指数较原位置降低21.7%。  相似文献   
992.
针对时间反演(time reversal, TR)技术无法较好地解决聚焦区内非法用户窃听的问题,提出了一种TR技术联合接收端人工噪声的物理层安全传输方案。首先,利用时间反演技术的空时聚焦性提高合法用户接收端的信噪比(signal to noise ratio, SNR)。其次,通过在接收端加入人工噪声来干扰非法用户对合法用户保密信息的窃听,以聚焦区内外系统安全性能为基础,推导出保密信干噪比(signal to interference plus noise ratio, SINR)、可达保密速率和误码率(bit error rate, BER)的解析表达式。最后,通过仿真分析证明了所提方案能提高系统的SINR和可达保密速率,同时还能降低合法用户的BER,使系统拥有更好的安全性能。  相似文献   
993.
王嘉力  Xie  Zongwu  Liu  Hong  Jiang  Li  Gao  Xiaohui 《高技术通讯(英文版)》2006,12(3):235-238
This paper presents a new designed miniature six DOF (degree of freedom) force/torque sensor. This sensor is fully integrated with a micro DSP (digital signal processor), so all the signal conditioning, A/D, decoupling, digital-signals serial output are performed in the sensor. Some experimental results are presented to demonstrate the capability of the proposed design. Finally, a neural network was used for decoupling the interacting signals, compared with the conventional method using the inverse matrix, this new method is more accurate.  相似文献   
994.
995.
Mutations of cystic fibrosis transmembrane conductance regulator (CFTR) cause cystic fibrosis, the most common life-limiting recessive genetic disease among Caucasians. CFTR mutations have also been linked to increased risk of various cancers but remained controversial for a long time. Recent studies have begun to reveal that CFTR is not merely an ion channel but also an important regulator of cancer development and progression with multiple signaling pathways identified. In this review, we will first present clinical findings showing the correlation of genetic mutations or aberrant expression of CFTR with cancer incidence in multiple cancers. We will then focus on the roles of CFTR in fundamental cellular processes including transformation, survival, proliferation, migration, invasion and epithelial–mesenchymal transition in cancer cells, highlighting the signaling pathways involved. Finally, the association of CFTR expression levels with patient prognosis, and the potential of CFTR as a cancer prognosis indicator in human malignancies will be discussed.  相似文献   
996.
本文研究了煤层瓦斯解吸-扩散-渗流的运移规律;分析了多分支水平井技术的增透机理:增大瓦斯解吸影响面积,沟通煤层裂隙并促进裂隙发育,降低瓦斯流动阻力。以山西晋城煤层气田为例,通过分支井产量模型研究分析得出分支数目和分支段长对产能的影响关系:分支井数目越大,抽采效果越好;分支井长度越长,抽采效果越好。  相似文献   
997.
998.
Hu Z  Xia Y  Guo X  Dai J  Li H  Hu H  Jiang Y  Lu F  Wu Y  Yang X  Li H  Yao B  Lu C  Xiong C  Li Z  Gui Y  Liu J  Zhou Z  Shen H  Wang X  Sha J 《Nature genetics》2012,44(2):183-186
Non-obstructive azoospermia (NOA) is one of the most severe forms of male infertility. Its pathophysiology is largely unknown, and few genetic influences have been defined. To identify common variants contributing to NOA in Han Chinese men, we performed a three-stage genome-wide association study of 2,927 individuals with NOA and 5,734 controls. The combined analyses identified significant (P < 5.0 × 10(-8)) associations between NOA risk and common variants near PRMT6 (rs12097821 at 1p13.3: odds ratio (OR) = 1.25, P = 5.7 × 10(-10)), PEX10 (rs2477686 at 1p36.32: OR = 1.39, P = 5.7 × 10(-12)) and SOX5 (rs10842262 at 12p12.1: OR = 1.23, P = 2.3 × 10(-9)). These findings implicate genetic variants at 1p13.3, 1p36.32 and 12p12.1 in the etiology of NOA in Han Chinese men.  相似文献   
999.
Opisthorchis viverrini-related cholangiocarcinoma (CCA), a fatal bile duct cancer, is a major public health concern in areas endemic for this parasite. We report here whole-exome sequencing of eight O. viverrini-related tumors and matched normal tissue. We identified and validated 206 somatic mutations in 187 genes using Sanger sequencing and selected 15 genes for mutation prevalence screening in an additional 46 individuals with CCA (cases). In addition to the known cancer-related genes TP53 (mutated in 44.4% of cases), KRAS (16.7%) and SMAD4 (16.7%), we identified somatic mutations in 10 newly implicated genes in 14.8-3.7% of cases. These included inactivating mutations in MLL3 (in 14.8% of cases), ROBO2 (9.3%), RNF43 (9.3%) and PEG3 (5.6%), and activating mutations in the GNAS oncogene (9.3%). These genes have functions that can be broadly grouped into three biological classes: (i) deactivation of histone modifiers, (ii) activation of G protein signaling and (iii) loss of genome stability. This study provides insight into the mutational landscape contributing to O. viverrini-related CCA.  相似文献   
1000.
Gui Y  Guo G  Huang Y  Hu X  Tang A  Gao S  Wu R  Chen C  Li X  Zhou L  He M  Li Z  Sun X  Jia W  Chen J  Yang S  Zhou F  Zhao X  Wan S  Ye R  Liang C  Liu Z  Huang P  Liu C  Jiang H  Wang Y  Zheng H  Sun L  Liu X  Jiang Z  Feng D  Chen J  Wu S  Zou J  Zhang Z  Yang R  Zhao J  Xu C  Yin W  Guan Z  Ye J  Zhang H  Li J  Kristiansen K  Nickerson ML  Theodorescu D  Li Y  Zhang X  Li S  Wang J  Yang H  Wang J  Cai Z 《Nature genetics》2011,43(9):875-878
Transitional cell carcinoma (TCC) is the most common type of bladder cancer. Here we sequenced the exomes of nine individuals with TCC and screened all the somatically mutated genes in a prevalence set of 88 additional individuals with TCC with different tumor stages and grades. In our study, we discovered a variety of genes previously unknown to be mutated in TCC. Notably, we identified genetic aberrations of the chromatin remodeling genes (UTX, MLL-MLL3, CREBBP-EP300, NCOR1, ARID1A and CHD6) in 59% of our 97 subjects with TCC. Of these genes, we showed UTX to be altered substantially more frequently in tumors of low stages and grades, highlighting its potential role in the classification and diagnosis of bladder cancer. Our results provide an overview of the genetic basis of TCC and suggest that aberration of chromatin regulation might be a hallmark of bladder cancer.  相似文献   
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