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961.
A new method based on image matching and frame coupling to handle the problems of object detection caused by a moving camera and object motion is presented in this paper. First, feature points are extracted from each frame. Then, motion parameters can be obtained. Sub-images are extracted from the corresponding frame via these motion parameters. Furthermore, a novel searching method for potential orientations improves efficiency and accuracy. Finally, a method based on frame coupling is adopted, which improves the accuracy of object detection. The results demonstrate the effectiveness and feasibility of our proposed method for a moving object with changing posture and with a moving camera.  相似文献   
962.
963.
Declined vasorelaxation function in aging resistance arteries is responsible for aging-related multiple organ dysfunctions. The aim of the present study is to explore the role of peroxynitrite (ONOO-) in aging resistance arterial vasorelaxation dysfunction and the possible mechanism. In the present study, young (3–4 months olds) and aging (20 months olds) male SD rats were randomized to receive vehicle (Saline) or FeTMPyP (ONOO- scavenger) for 2 weeks. The vasorelaxation of resistance arteries was determined in vitro; NOx level was tested by a colorimetric assay; the expression of nitrotyrosine (NT), soluble Guanylate Cyclase (sGC), vasodilator-stimulated phosphoprotein (VASP), phosphorylated VASP (P-VASP) and cGMP in resistance arteries were detected by immunohistochemical staining. In the present study, endothelium-dependent dilation in aging resistance arteries was lower than in those from young rats (young vs. aging: 68.0%±4.5% vs. 50.4%±2.9%, P<0.01). And the endothelium-independent dilation remained constant. Compared with young rats, aging increased nitrative stress in resistance arteries, evidenced by elevated NOx production in serum (5.3±1.0 nmol/ml vs. 3.3±1.4 nmol/ml, P<0.05) and increased NT expression (P<0.05). ONOO- was responsible for the vasorelaxation dysfunction, evidenced by normalized vasorelaxation after inhibit ONOO- or its sources (P<0.05) and suppressed NT expression after FeTMPyP treatment (P<0.05). The expression of sGC was not significantly different between young and aging resistance arteries, but the cGMP level and P-VASP/VASP ratio (biochemical marker of NO-sGC-cGKs signaling) decreased, which was reversed by FeTMPyP treatment in vivo (P<0.05). The present study suggested that ONOO- mediated the decline of endothelium-dependent vasorelaxation of aging resistance arteries by induction of the NO-sGC-cGKs pathway dysfunction.  相似文献   
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966.
With the rapid growth of the Internet and overwhelming amount of information and choices that people are confronted with, recommender systems have been developed to effectively support users’ decision-making process in the online systems. However, many recommendation algorithms suffer from the data sparsity problem, i.e. the user-object bipartite networks are so sparse that algorithms cannot accurately recommend objects for users. This data sparsity problem makes many well-known recommendation algorithms perform poorly. To solve the problem, we propose a recommendation algorithm based on the semi-local diffusion process on the user-object bipartite network. The simulation results on two sparse datasets, Amazon and Bookcross, show that our method significantly outperforms the state-of-the-art methods especially for those small-degree users. Two personalized semi-local diffusion methods are proposed which further improve the recommendation accuracy. Finally, our work indicates that sparse online systems are essentially different from the dense online systems, so it is necessary to reexamine former algorithms and conclusions based on dense data in sparse systems.  相似文献   
967.
Molecular mechanisms and gene regulation are of interest in the area of geomicrobiology in which the interaction between microbes and minerals is studied. This paper focuses on the regulation of the expression of carbonic anhydrase (CA) genes in Bacillus mucilaginosus and the effects of the expression product of the B. mucilaginosus CA gene in Escherichia coli on calcite weathering. Real-time fluorescent quantitative PCR (RT-qPCR) was used to explore the relationship between CA gene expression in B. mucilaginosus and promotion of calcite dissolution under condition of Ca2+ deficiency. The results showed that adding calcite to the medium, which lacks Ca2+, can up-regulate the expression of the bacterial CA genes to accelerate calcite dissolution for bacterial growth. CA genes from B. mucilaginosus were transferred into E. coli by cloning. We then employed crude enzyme extract from the resultant E. coli strain in calcite dissolution experiments. The enzyme extract promoted calcite dissolution. These findings provide direct evidence for the role of microbial CA on mineral weathering and mineral nutrition release.  相似文献   
968.
Xu  Simin  Cao  Jiayi  Wu  Minnan  Xu  Yijun  Wu  Yuanyuan  Shang  Kaixi  Ma  Bin  Zhang  Lin  Chen  Deshui  Liu  Xinyu  Yan  Xiaojun  Xu  Jilin 《Marine biotechnology (New York, N.Y.)》2023,25(3):463-472
Marine Biotechnology - Isochrysis zhangjiangensis is an important microalgal species used as bait in aquaculture. However, its optimal cultivation temperature is around 25&nbsp;°C,...  相似文献   
969.

Auxin response factor (ARF) is a key component of auxin signal. The study of MdARF8 gene in apple shows that it is involved in the process of jasmonate regulating plant growth and development. Methyl jasmonate (MeJA) treatment inhibited the growth process of apple calli, and ARF8 played a negative regulatory role in this pathway. The results of ectopic expression in Arabidopsis showed that MdARF8 could reduce the sensitivity of Arabidopsis to MeJA and alleviate the phenotype of promoting leaf senescence and inhibiting taproot elongation. Further results showed that the dysplastic phenotype of transgenic Arabidopsis root hair could be partially recovered by MeJA treatment. This study provided valuable clues for functional characterization of ARF8 and signal crosstalk between jasmonate and auxin in apple.

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970.
本文作者采用基因克隆手段,以pAt153为载体,从一份山西襄坦宫颈癌高发区宫颈癌患者的手术标本中,成功地克隆到2株与HPV16同源的基因片段。经PstI、KpnI、TaqvI、PvuII等16种限制性内切酶酶谱分析及其部分基因序列的鉴定,证明这是在国内首次克姓到一株分子量约为8.0kb完整的HPV16型全序列DNA及一株分子量为5.4kb的HPV6基因片段。经实验证明:该基因片段E6、E7及部分LI基因丢失,在750单核苷酸处发生变异,产生一新的BamHI酶切位点。该完整的HPV16基因组被命名为HPV16Z,HPV16基因片段被命名为HPV16F。用新分离到的HPV16Z作分子探针,检测襄坦337份宫颈癌及阴道活检标本的HPV16型同源序列的结果显示,慢性阴道炎阳性率为17.28%(14/81);宫颈炎为11.89%(17/143);宫颈癌前病变46.81%(22/47);宫颈癌为72.73%(48/66)。证明山西宫颈癌高发区宫颈癌前病变及宫颈癌组织中主要为HPV16Z感染。  相似文献   
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