Weaving marine food webs from end to end under global change

Marine food web dynamics are determined by interactions within and between species and between species and their environment. Global change directly affects abiotic conditions and living organisms, impinging on all trophic levels in food webs. Different groups of marine researchers traditionally study different aspects of these changes. However, over medium to long time scales perturbations affecting food webs need to be considered across the full range from nutrients to top predators. Studies of end-to-end marine food webs not only span organism sizes and trophic levels, but should also help align multidisciplinary research to common goals and perspectives. Topics are described that bridge disciplinary gaps and are needed to develop new understanding of the reciprocal impacts of global change on marine food webs and ocean biogeochemistry. These include (1) the effects of nutrients on biomass and production, (2) the effects of varying element ratios on food web structure and food quality, (3) bulk flows of energy and material in food webs and their efficiencies of transfer, (4) the ecological effects of species richness and the roles of microbial organisms, (5) the role of feeding behaviour in food web dynamics and trophic controls, (6) the spatial dynamics of communities and links between different food webs, (7) the combined effects of body size and behaviour in determining dynamics of food webs, and (8) the extent to which the ability of marine organisms (and communities) to adapt will influence food web dynamics. An overriding issue that influences all topics concerns the time and space scales of ecosystem variability. Threads link different nodes of information among various topics, emphasizing the importance of tackling food web studies with a variety of modelling approaches and through a combination of field and experimental studies with a strong comparative approach.     

TUMOR NECROSIS FACTOR－ALPHA SERUM LEVELS AND IN VITRO PRODUCTION IN PATIENTS WITH HUMAN IMMUNODEFICIENCY VIRUS（HIV） INFECTION

ＴＵＭＯＲＮＥＣＲＯＳＩＳＦＡＣＴＯＲ－ＡＬＰＨＡＳＥＲＵＭＬＥＶＥＬＳＡＮＤＩＮＶＩＴＲＯＰＲＯＤＵＣＴＩＯＮＩＮＰＡＴＩＥＮＴＳＷＩＴＨＨＵＭＡＮＩＭＭＵＮＯＤＥＦＩＣＩＥＮＣＹＶＩＲＵＳ（ＨＩＶ）ＩＮＦＥＣＴＩＯＮＷａｎｇＹｉｌｉ（王一理）；Ｓ...     

多抗甲素对同种移植物的保护作用

多抗甲素是从甲型链球菌培养物中提取的一种生物反应调节剂（ＢＲＭ），在体外同种混合淋巴细胞反应（ＭＬＲ）中能抑制特异性ＣＴＬ的产生（对照组：ｌ０２±７６溶解单位，实验组：３４±３４溶解单位，Ｐ＝０．００５），而对ＮＫ活性并无显著影响。滴定实验测定，１０ｍｇ／Ｌ时抑制作用尤为明显。同时用ＢＡＬＢ／Ｃ和Ｃ５７Ｂ／Ｌ小鼠间行皮肤移植，结果表明多抗甲素能明显延长移植物存活时间，可望用于临床移植，其作用机理需进一步研究。     

ESI,专业化的虚拟仿真技术推动数字化造船

在工程仿真领域,有一家以提供专业化的仿真解决方案享誉业界的公司引起了记者的注意,这家公司何以能在激烈的全球CAE行业中赢得越来越多的市场?其解决方案的特点是什么?其未来发展和技术研发方向是什么?面对中国技术创新的巨大机遇,以及中国已成为造船大国并向造船强国转型的时机下,该公司如何布局中国的CAE市场?其仿真技术和方案能给中国船舶工业转型过程技术创新带来什么益处?带着这些问题,在一个初冬的早晨,本刊记者对这家的全球运营官ChristopherSt.John博士进行了专访。     

Sail-assisted motor vessels weather routing using a fuzzy logic model

In this study sail-assisted motor vessels weather routing is investigated to establish the most economical route by applying available information of the ship's behavior regarding the encountered sea-conditions. To derive the vessel’s fuel use on a route, a fuzzy logic model is constructed through an automated identification process. Only data collected from actual integrated bridge measurements systems is used. Fuzzy modeling is a framework providing a flexible and transparent mathematical structure to describe the physical relationships in a vessel's behavior. This consumption model is integrated into a determinist weather-routing optimization workflow based on a systematic meshing scheme of the sailing area. Pareto-optimization with a multi-objective genetic algorithm is used to maximize fuel economy in a limited or optimum time. The benefits of the developed decision helping tool in sail-assisted motor vessel routing are highlighted on a westbound north Transatlantic journey.     

Forecasting Freight Flows

Trade patterns and transport markets are changing as a result of the growth and globalization of international trade, and forecasting future freight flow has to rely on trade forecasts. Forecasting freight flows is critical for matching infrastructure supply to demand and for assessing investment. This article models long-term dynamic physical trade flows and estimates a dynamic panel data model for foreign trade for the EU15 and two countries from the EFTA (European Free Trade Association) 1967–2002. The analysis suggests that a dynamic three-way-effects gravity equation is the best-fitted econometric model. The analysis uses a structural relationship to explain the structure of the exchange of the goods—a relationship that can be used in the year of forecast. This article also provides a new methodology for converting monetary aggregates into quantity aggregates. The resulting commodity growth rates constitute a valuable input to freight models for forecasting future capacity problems.     

Traffic congestion and economic context: changes of spatiotemporal patterns of traffic travel times during crisis and post-crisis periods

Transportation - This paper aims to evaluate the impacts of the economic context on traffic congestion and its consequential effects on private vehicle accessibility. We conduct a long-term...     

沙眼衣原体D型MOMP基因的克隆和序列分析

目的　从D型沙眼衣原体培养物中克隆主要外膜蛋白(MOMP)基因。方法　利用细胞培养法扩增沙眼衣原体后,提取基因组为模板,经聚合酶链反应(PCR)扩增全长MOMP基因,并用酶切、PCR扩增及序列测定等方法对重组质粒进行鉴定。结果　成功扩增了MOMP基因,并插入克隆载体 pUCmT中。结论　MOMP基因的克隆为进一步开展沙眼衣原体的疫苗研究奠定了基础。     

pSVL/GM-CSF真核表达质粒的构建及其表达活性观察

以真核瞬时表达质粒ｐＳＶＬ为载体构建ｐＳＶＬ／ＧＭ－ＣＳＦ真核表达质粒，用电穿孔法导入Ｃｏｓ－７细胞，以ＧＭ－ＣＳＦ依赖株ＴＦ１为靶细胞，检测其生物学活性；将不同剂量的ＰＳＶＬ／ＧＭ－ＣＳＦ质粒直接注射Ｂａ１ｂ／Ｃ小鼠股四头肌，动态观察小鼠血清中ＧＭ－ＣＳＦ的表达；将ｐＳＶＬ／ＧＭ－ＣＳＦ质粒导入Ｋ５６２细胞，观察ＧＭ－ＣＳＦ对瘤细胞生长状态的影响。结果表明：构建的ｐＳＶＬ／ＧＭ－ＣＳＦ真核表达质粒可在Ｃｏｓ－７细胞中有效表达ＧＭ－ＣＳＦ；小鼠骨骼肌直接注射ｐＳＶＬ／ＧＭ－ＣＳＦ（１００μｇ／及２００μｇ），在血清中可检出ＧＭ－ＣＳＦ，在１０～１５ｄ达高峰（８Ｕ／ｍｌ），为临床应用提供了实验基础；导入ＧＭ－ＣＳＦ基因的Ｋ５６２细胞可表达ＧＭ－ＣＳＦ，且经ＧＭ－ＣＳＦ基因修饰的Ｋ５６２细胞增殖状态明显优于对照组，提示对造血细胞肿瘤单用ＧＭ－ＣＳＦ应慎重，而与其它细胞因子联合应用可能是一个合理的方案。     

迈腾B8L轿车电动车窗故障诊断分析

文章以一汽大众2018款迈腾B8L2.0TSI轿车为例,分析电动车窗系统电路,并结合一起真实的故障案例,诊断分析出故障原因,为汽车类似的系统故障诊断分析提供一定的参考。