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971.
软件构架在对可靠性、可移植性、安全性等性能要求比较高的软件开发过程中起着重要的作用.构架的好坏直接关系到系统的成功与否.根据实际需求,在设计中采用了模块视图分层风格,把系统的责任分解成小模块,使变更被隔离在一个模块内,大大提高了软件复用率,符合企业信息化的发展要求. 相似文献
972.
电感式接近开关的封装形式中,全金属封装是比较常见的一种类型.目前,市场上的电感式接近开关,包括具有内腔的外壳和设置在内腔中的开关组件,其开关组件多采用环氧树脂固定在内腔中.在这类接近开关的失效分析工作中,由于难以去除金属外壳及内部灌封树脂,常使失效分析工作难以开展.论文结合一款全金属封装的电感式接近开关的失效案例,在不... 相似文献
973.
974.
富氧炭浸提金工艺在哈德门金矿的应用 总被引:2,自引:1,他引:1
介绍了富氧炭浸提金工艺在哈德门金矿二期扩建工程中的应用。在不增加浸出设备的前提下,生产能力由一期的300t/d提高到600t/d,浸出时间由30h缩短为15h,氰化物消耗下降,而富氧前后浸出率相当;节省了基建投资,降低了生产成本。 相似文献
975.
为了有效控制红外弱小目标检测过程中的虚警率,提高复杂云背景下的目标检测准确度,提出了基于空域-频域映射与虚警抑制的弱小目标检测算法。根据红外中心像素不同方向上的强度值,构建了方向最大中值滤波器,有效消除噪声;并利用中心像素与其邻域像素的强度差异,形成背景抑制滤波,充分增强弱小目标;考虑云区域的特有属性,联合非线性滤波,定义了云区域识别机制,提取空域映射;引入Butterworth差异低通滤波器,对去噪图像中的显著目标完成初步识别;基于其幅度信息,进行显著目标的精细检测;再利用细显著性检测结果,计算阈值,利用二值分割方法来获取去噪红外图像的频域映射;联合空域映射与频域映射,提取红外图像中的候选目标;根据真实动目标与虚警之间的运动特征差异,利用多尺度改进的管道滤波来抑制虚警,准确识别出真实目标。实验数据表明,相对于已有的弱小目标识别方案,所提方案能够准确地识别出真实目标,拥有更好的ROC特性曲线。 相似文献
976.
Binwen Tan Miaomiao Wang Li Cai Sanyue Li Wei Zhu Lili Xu Yi Wang Jian Zeng Xing Fan Lina Sha Dandan Wu Yiran Cheng Haiqin Zhang Guoyue Chen Yonghong Zhou Houyang Kang 《International journal of molecular sciences》2022,23(18)
Powdery mildew caused by Blumeria graminis f. sp. tritici is a devastating disease that reduces wheat yield and quality worldwide. The exploration and utilization of new resistance genes from wild wheat relatives is the most effective strategy against this disease. Psathyrostachys huashanica Keng f. ex P. C. Kuo (2n = 2x = 14, NsNs) is an important tertiary gene donor with multiple valuable traits for wheat genetic improvement, especially disease resistance. In this study, we developed and identified a new wheat—P. huashanica disomic addition line, 18-1-5—derived from a cross between P. huashanica and common wheat lines Chinese Spring and CSph2b. Sequential genomic and multicolor fluorescence in situ hybridization analyses revealed that 18-1-5 harbored 21 pairs of wheat chromosomes plus a pair of alien Ns chromosomes. Non-denaturing fluorescence in situ hybridization and molecular marker analyses further demonstrated that the alien chromosomes were derived from chromosome 7Ns of P. huashanica. The assessment of powdery mildew response revealed that line 18-1-5 was highly resistant at the adult stage to powdery mildew pathogens prevalent in China. The evaluation of agronomic traits indicated that 18-1-5 had a significantly reduced plant height and an increased kernel length compared with its wheat parents. Using genotyping-by-sequencing technology, we developed 118 PCR-based markers specifically for chromosome 7Ns of P. huashanica and found that 26 of these markers could be used to distinguish the genomes of P. huashanica and other wheat-related species. Line 18-1-5 can therefore serve as a promising bridging parent for wheat disease resistance breeding. These markers should be conducive for the rapid, precise detection of P. huashanica chromosomes and chromosomal segments carrying Pm resistance gene(s) during marker-assisted breeding and for the investigation of genetic differences and phylogenetic relationships among diverse Ns genomes and other closely related ones. 相似文献
977.
978.
Yan-Ruide Li Yang Zhou Matthew Wilson Adam Kramer Ryan Hon Yichen Zhu Ying Fang Lili Yang 《International journal of molecular sciences》2022,23(14)
Invariant natural killer T (iNKT) cells have the capacity to mount potent anti-tumor reactivity and have therefore become a focus in the development of cell-based immunotherapy. iNKT cells attack tumor cells using multiple mechanisms with a high efficacy; however, their clinical application has been limited because of their low numbers in cancer patients and difficulties in infiltrating solid tumors. In this study, we aimed to overcome these critical limitations by using α-GalCer, a synthetic glycolipid ligand specifically activating iNKT cells, to recruit iNKT to solid tumors. By adoptively transferring human iNKT cells into tumor-bearing humanized NSG mice and administering a single dose of tumor-localized α-GalCer, we demonstrated the rapid recruitment of human iNKT cells into solid tumors in as little as one day and a significantly enhanced tumor killing ability. Using firefly luciferase-labeled iNKT cells, we monitored the tissue biodistribution and pharmacokinetics/pharmacodynamics (PK/PD) of human iNKT cells in tumor-bearing NSG mice. Collectively, these preclinical studies demonstrate the promise of an αGC-driven iNKT cell-based immunotherapy to target solid tumors with higher efficacy and precision. 相似文献
979.
980.
Zahirul I. Talukder William Underwood Christopher G. Misar Gerald J. Seiler Xiwen Cai Xuehui Li Lili Qi 《International journal of molecular sciences》2022,23(14)
Sclerotinia head rot (HR), caused by Sclerotinia sclerotiorum, is an economically important disease of sunflower with known detrimental effects on yield and quality in humid climates worldwide. The objective of this study was to gain insight into the genetic architecture of HR resistance from a sunflower line HR21 harboring HR resistance introgressed from the wild perennial Helianthus maximiliani. An F2 population derived from the cross of HA 234 (susceptible-line)/HR21 (resistant-line) was evaluated for HR resistance at two locations during 2019–2020. Highly significant genetic variations (p < 0.001) were observed for HR disease incidence (DI) and disease severity (DS) in both individual and combined analyses. Broad sense heritability (H2) estimates across environments for DI and DS were 0.51 and 0.62, respectively. A high-density genetic map of 1420.287 cM was constructed with 6315 SNP/InDel markers developed using genotype-by-sequencing technology. A total of 16 genomic regions on eight sunflower chromosomes, 1, 2, 10, 12, 13, 14, 16 and 17 were associated with HR resistance, each explaining between 3.97 to 16.67% of the phenotypic variance for HR resistance. Eleven of these QTL had resistance alleles from the HR21 parent. Molecular markers flanking the QTL will facilitate marker-assisted selection breeding for HR resistance in sunflower. 相似文献