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Neutrophils are being increasingly recognized as an important element in tumor progression. They have been shown to exert important effects at nearly every stage of tumor progression with a number of studies demonstrating that their presence is critical to tumor development. Novel aspects of neutrophil biology have recently been elucidated and its contribution to tumorigenesis is only beginning to be appreciated. Neutrophil extracellular traps (NETs) are neutrophil-derived structures composed of DNA decorated with antimicrobial peptides. They have been shown to trap and kill microorganisms, playing a critical role in host defense. However, their contribution to tumor development and metastasis has recently been demonstrated in a number of studies highlighting NETs as a potentially important therapeutic target. Here, studies implicating NETs as facilitators of tumor progression and metastasis are reviewed. In addition, potential mechanisms by which NETs may exert these effects are explored. Finally, the ability to target NETs therapeutically in human neoplastic disease is highlighted.  相似文献   
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In this article we discuss how an interdisciplinary research team partnered with a variety of stakeholders concerned with and/or affected by the impacts of climate change in the Red River Delta of Vietnam. The research, undertaken from 2016 to 2018, drew upon a wide range of methods to investigate systemically these impacts – with a view to the research inputting into the development of (more) sustainable ways of living. The research solicited various accounts of the experience of climate change in the community, set up learning processes in community meetings, and created an interface with government officials positioned at commune, district, provincial, and national levels. The intention was to offer support towards developing a learning process (broadly defined as including learnings/systemic inquiry across organizational levels of the society) to pursue options for sustainable living. The article offers our post-facto reflections which render more explicit (to ourselves and for the benefit of audiences) how the research team, with Hoang as lead researcher, facilitated the inquiry process towards developing a synthesis which underscored the assets for resilience to climate change and supported interventions to strengthen such (defined) assets.

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Science Bulletin - The Mid-Miocene Climatic Optimum (MMCO; ~15–17 Ma) was one of the short-term climatic warm events that punctuated the Cenozoic long-term cooling trend. Because...  相似文献   
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The range of possibilities for future climate evolution needs to be taken into account when planning climate change mitigation and adaptation strategies. This requires ensembles of multi-decadal simulations to assess both chaotic climate variability and model response uncertainty. Statistical estimates of model response uncertainty, based on observations of recent climate change, admit climate sensitivities--defined as the equilibrium response of global mean temperature to doubling levels of atmospheric carbon dioxide--substantially greater than 5 K. But such strong responses are not used in ranges for future climate change because they have not been seen in general circulation models. Here we present results from the 'climateprediction.net' experiment, the first multi-thousand-member grand ensemble of simulations using a general circulation model and thereby explicitly resolving regional details. We find model versions as realistic as other state-of-the-art climate models but with climate sensitivities ranging from less than 2 K to more than 11 K. Models with such extreme sensitivities are critical for the study of the full range of possible responses of the climate system to rising greenhouse gas levels, and for assessing the risks associated with specific targets for stabilizing these levels.  相似文献   
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辽宁本溪地区条带状铁矿(BIF)与其玄武质火山围岩之间的时空关联非常密切.对于玄武质火山围岩高场强元素(HFSE)的研究表明:wNb/wTa比值(7.00~19.93)表现出明显的分异,而wZr/wHf比值(33.46~38.28)则变化不大;从弓长岭到南芬、歪头山样品的wNb/wTa比值变化具有明显的循序性.这种高场强元素的迁移和分异特征反映出俯冲作用与盆地演化之间的关联.研究区玄武质火山围岩(wNb/wYb)N比值大于1(1.21~18.45,平均2.72),这进一步表明,其形成的构造背景为陆内弧后盆地提供了有利于BIF形成的条件.  相似文献   
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为了从不锈钢粉尘中回收利用Fe,Cr和Ni等,对不锈钢粉尘热压块制备及其自还原过程进行了研究.在热压温度为200℃,热压压力为35 MPa条件下,抗压强度达到900 N/个以上.高温条件下,煤热解产生的挥发分可参与不锈钢粉尘还原反应,当还原温度为1 400,1 450℃时,挥发分还原作用率达到0.4.据XRD分析和热力学计算,自还原过程中含铬物质的物相转变顺序为Fe Cr2O4,Cr2O3,Cr7C3,[Cr]Fe-Cr-Ni-C.当还原温度为1 450℃,烟煤中固定碳与粉尘中可去除氧的物质量的比(xc/xo)为0.72时,不锈钢粉尘热压块不能完全还原;当xc/xo大于0.8,还原20 min时,不锈钢粉尘热压块能完全还原.  相似文献   
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Constant elevation of southern Tibet over the past 15 million years   总被引:53,自引:0,他引:53  
The uplift of the Tibetan plateau, an area that is 2,000 km wide, to an altitude of about 5,000 m has been shown to modify global climate and to influence monsoon intensity. Mechanical and thermal models for homogeneous thickening of the lithosphere make specific predictions about uplift rates of the Tibetan plateau, but the precise history of the uplift of the plateau has yet to be confirmed by observations. Here we present well-preserved fossil leaf assemblages from the Namling basin, southern Tibet, dated to approximately 15 Myr ago, which allow us to reconstruct the temperatures within the basin at that time. Using a numerical general circulation model to estimate moist static energy at the location of the fossil leaves, we reconstruct the elevation of the Namling basin 15 Myr ago to be 4,689 +/- 895 m or 4,638 +/- 847 m, depending on the reference data used. This is comparable to the present-day altitude of 4,600 m. We conclude that the elevation of the southern Tibetan plateau probably has remained unchanged for the past 15 Myr.  相似文献   
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