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991.
ABSTRACTIn view of the risk characteristics of large group decision-making in emergencies and the difficultly in forming the decision scheme with low risk, the causes of generating risk in urgent group decisions are analyzed. The coordination framework for risk elimination in emergency decisions is constructed. The methods of risk measure and elimination for emergency decisions are proposed to construct the risk elimination coordination mechanism for emergency decisions so that the risk of emergency group decisions is gradually constringed to obtain the emergency decision scheme with risk degree low enough. Finally, an example case is used to validate the realization process and the validity of risk elimination coordination method and mechanism. 相似文献
992.
993.
994.
In this study we provide an update to the taxonomy of the ant genus Tetramorium Mayr in Madagascar. We report the first record of the Tetramorium
setigerum species group in Madagascar and describe the only Malagasy representative as Tetramorium
cavernicola
sp. n., which is known only from a cave in Ankarana. In addition, we provide an overview of the 19 proposed Malagasy species groups, and discuss their zoogeography and relationships to other groups and larger lineages within the hyper-diverse genus Tetramorium. At present, we recognise a highly unique Malagasy Tetramorium fauna with 113 species endemic to the island of Madagascar out of a total of 125 translating into an endemism rate of 93%. We hypothesise that this fauna is based on one or a few colonisation events from the Afrotropical region, with subsequent adaptive radiation in Madagascar. Furthermore, we present an updated and illustrated identification key to the Tetramorium species groups in the Malagasy region. 相似文献
995.
Redox status of high‐mobility group box 1 performs a dual role in angiogenesis of colorectal carcinoma 下载免费PDF全文
Lingyin Zhu Lin Ren Yingxuan Chen Jingyuan Fang Zhizheng Ge Xiaobo Li 《Journal of cellular and molecular medicine》2015,19(9):2128-2135
During inflammation, high‐mobility group box 1 in reduced all‐thiol form (at‐HMGB1) takes charge of chemoattractant activity, whereas only disulfide‐HMGB1 (ds‐HMGB1) has cytokine activity. Also as pro‐angiogenic inducer, the role of HMGB1 in different redox states has never been defined in tumour angiogenesis. To verify which redox states of HMGB1 induces angiogenesis in colorectal carcinoma. To measure the expression of VEGF‐A and angiogenic properties of the endothelial cells (ECs), at‐HMGB1 or ds‐HMGB1 was added to cell medium, further with their special inhibitors (DPH1.1 mAb and 2G7 mAb) and antibodies of corresponding receptors (RAGE Ab and TLR4 Ab). Also, a co‐culture system and conditioned medium from tumour cells were applied to mimic tumour microenvironment. HMGB1 triggered VEGF‐A secretion mainly through its disulfide form interacting with TLR4, while co‐operation of at‐HMGB1 and RAGE mediated migratory capacity of ECs. Functional inhibition of HMGB1 and its receptors abrogated HMGB1‐induced angiogenic properties of ECs co‐cultured with tumour cells. HMGB1 orchestrates the key events of tumour angiogenesis, migration of ECs and their induction to secrete VEGF‐A, by adopting distinct redox states. 相似文献
996.
Delphine Durieux Bérénice Fassotte Jean‐Louis Deneubourg Yves Brostaux Axel Vandereycken Emilie Joie Eric Haubruge François J. Verheggen 《Insect Science》2015,22(5):670-678
The invasive multicolored Asian ladybeetle, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), aggregates inside dwellings during winter to avoid cold weather. This adaptive behavior disturbs homeowners, because of the large numbers of individuals that aggregate, which induces allergic reactions. The migratory flight patterns of this species have been well documented, with individuals preferentially moving toward prominent and high color contrast elements. However, the factors involved in the selection of aggregation sites by this species have yet to be elucidated. Here, we evaluated the influence of (i) the density of individuals and (ii) the type of available shelters on decisions by H. axyridis to settle and aggregate under shelters. A dual choice bioassay conducted in the laboratory demonstrated the presence of mutual attraction to conspecifics. We also found that individuals preferentially settled under red covered shelters compared to transparent shelters, and that the type of shelter outweighed the effect of social interactions among conspecifics. Moreover, this experiment was performed under non‐wintering conditions, providing the first evidence that aggregative behavior in this species can also occur under those specific conditions. 相似文献
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998.
Aditya Sudheer Vaidya Raghupathi Neelarapu Antonett Madriaga He Bai Emma Mendonca Hazem Abdelkarim Richard B. van Breemen Sylvie Y. Blond Pavel A. Petukhov 《Bioorganic & medicinal chemistry letters》2012,22(21):6621-6627
A novel series of HDAC8 inhibitors without a zinc-chelating hydroxamic acid moiety is reported. Photoaffinity labeling and molecular modeling studies suggest that these ligands are likely to bind in an ‘upside-down’ fashion in a secondary binding site proximal to the main catalytic site. The most potent ligand in the series exhibits an IC50 of 28 μM for HDAC8 and is found to inhibit the deacetylation of H4 but not α-tubulin in SH-SY5Y cell line. 相似文献
999.
选取黄土高原区黑岱沟露天煤矿不同复垦阶段(1995~2010年)样地4块,以原地貌样地为对照,以时空替代的方法,对煤矿复垦地的植物群落的功能群结构及生物多样性进行研究.结果表明:(1)随着复垦时间的延长,植物群落功能群组成以多年生禾草和多年生杂类草为主,其累积优势度均呈现增加的趋势,而一、二年生草本的累积优势度减小;复垦初期,群落功能群单一、组成种类贫乏,多为一、二年生植物;复垦后期,羊草及冰草逐步出现,复垦地最终形成以克氏针茅、本氏针茅、赖草及糙隐子草为主的植物群落.(2)复垦过程中,中生植物及中旱生植物所占比例逐步增加,而旱生植物比例逐步减少;多年生禾草及多年生杂类草生物量随着复垦时间的增加而递增,而一、二年生草本植物生物量递减;群落总生物量呈先急剧增加、又急剧减少、后缓慢增加的规律.(3)群落的Shan-non-Wiener多样性指数(H)、Patrick丰富度指数(Pa)及Pielou均匀度指数(JP)随着复垦时间延长而增加. 相似文献
1000.
Dongmei Zhang Linlin Sun Haiyan Zhu Lan Wang Weicheng Wu Jianhui Xie Jianxin Gu 《Neurochemistry international》2012
Chronic neurodegeneration is in part caused by a vicious cycle of persistent microglial activation and progressive neuronal cell loss. However, the driving force behind this cycle remains poorly understood. In this study, we used medium conditioned by necrotic differentiated-PC12 cells to confirm that damaged neurons can release soluble injury signals, including heat shock protein 60 (HSP60), to efficiently promote the neurotoxic cycle involving microglia. Since lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) has previously been identified as a novel receptor for HSP60, we hypothesize that LOX-1 through binding to extracellular HSP60 promotes microglia-mediated neuroinflammation. In this study, we observed that LOX-1 expression is induced upon toxic microglial activation, and discovered that LOX-1 is necessary in microglia for sensing soluble neuronal injury signal(s) in the conditioned medium to induce generation of pro-inflammatory mediators (IL-1β, TNF-α, NO and ROS) that promote neurotoxicity. Employing a unique eukaryotic HSP60-overexpression method, we further demonstrated that extracellular HSP60 acts on microglial LOX-1 to boost the production of pro-inflammatory factors (IL-1β, NO and ROS) in microglia and to propagate neuronal damage. These results indicate that LOX-1 is essential in microglia for promoting an inflammatory response in the presence of soluble neuronal-injury signals such as extracellular HSP60, thereby linking neuroinflammation and neurotoxicity. 相似文献