我国涉外协议管辖制度的完善

当代国际社会在协议管辖制度上形成了扩大其适用范围、放宽其形式要件、弱化被选择法院与案件联系因素的宽松化趋势,并同时出现了公共政策和弱者保护原则对其加以限制的倾向。我国的涉外协议管辖制度基本上没有反映出上述趋向,因而应进行适当的完善。不过,在目前,由于案件国际转移现象的可能性,我国还须坚持"实际联系原则"

美国风险收费制度对我国的启示

美国风险收费制度是根据案件的具体结果来支付律师费用的一种制度,案件胜诉则支付约定的费用,反之则不需或少付律师费用。虽然对于我国是否可采纳风险收费制度有不同的观点,但由于风险收费制度有利于解决我国目前面临的诉讼难的困境,以及对公益诉讼有不可低估的意义,因而在一定限度内采用应该是可行的。Contingent Fees System is such a system in which the plaintiff may pay for lawyer according to the final results of the case, if he won, he pays, otherwise, no pay There are some different opinions on whether to adopt the system in China, but because it can extricate from the difficult position of litigation and enforcement, and it is significant for Public Benefit Litigation, it can be adopted in limited scop

Effects of mowing plus waterlogging on germination and seedling growth of Spartina alterniflora

互花米草(Spartina alterniflora)是我国危害最严重的外来入侵植物之一,探索环保、经济、有效地防治互花米草的技术对保护我国海滩生态环境具有重要意义。本研究通过人工气候室(20~25℃)的盆栽实验,研究刈割与淹水对互花米草萌发和幼苗生长的影响。实验持续4个月,对互花米草地上部分进行了2次刈割,首次刈割是在互花米草生长季结束时,3个月后进行第二次刈割。首次刈割后持续淹水至实验结束,淹水处理设计0、5、10、20 cm四个淹水深度。首次刈割后各淹水处理互花米草根茎上迅速萌发克隆苗,种子的萌发比克隆苗晚约3个月。不同淹水深度对克隆苗的萌发和生长均有抑制作用,克隆苗株数、株高和地上生物量均随淹水深度增加而减少。第二次刈割后各淹水处理均没有再萌发克隆苗,但有少量种子实生苗,其中20 cm水深处理的实生苗数量最少。刈割加淹水可以很好地抑制互花米草的萌发和幼苗生长,据此建议互花米草防治方案为:在春季萌芽前,修筑堤坝,保持淹水20 cm,在营养生长期后期贴地刈割互花米草,继续淹水,第二年重复同样的刈割和淹水。为防止二次入侵,需要在邻近的互花米草分布区同时进行治理。&nbsp;</p

土壤养分和下行效应对滨海湿地植被的 联合调控机制研究进展

In coastal wetland ecology, most studies only consider the bottom-up effect, that is, the effect of abiotic factors on plant survival, growth and reproduction, while ignoring the top-down effect (i. e. , herbivory). On the other hand, the eutrophication situation is more serious than ever before in global coastal wetland, soil nutrient enrichment may affect the top-down effect and then in fluence the coastal wetland vegetation. Therefore, this paper aims to synthesize the mechanisms of soil nutrient and the top-down effect jointly regulating the coastal wetland plant population and community. Then we pointed out the limitations in current studies to provide references for the future studies: (1) How the unique plant groups and environmental factors of the coastal wetland responding to the joint influences of soil nutrient enrichment and the top-down effect needs to be studied; (2) lack of the long-term mechanism of soil nutrient enrichment and top-down effect on the coastal wetland vegetation; (3) investigating the top-down effect of parasitic and bacte rial consumers on the coastal wetland vegetation is rare. Additionally, we introduced the long-term experimental platform of soil nutri ents and top-down effects of the coastal wetland in Yellow River Delta, and it may provide important information to guide the conserva tion of coastal wetland vegetaion of the Yellow River Delta under the background of global change

基于峭度的VMD分解中k值的确定方法研究

在变分模态分解（Variational mode decomposition,VMD）中,因为分解层数k值属于自定义变量,所以在取值时分解结果会随着k值的变化而得到不同的结果,k值的取值直接影响着结果的准确性,k值取得过大或者过小都会对结果造成影响。基于以上问题,提出了一种利用峭度确定k值的方法。选取k值为2n的整数,计算当k值为2n时,每一个k值相关系数最大分量的峭度,并绘制峭度的变化曲线,若在该曲线内峭度没有峰值且单调递增,则继续计算当k为n+1时相关系数最大分量的峭度值,重复以上步骤,以峭度最大作为优化的标准,当峭度最大的时候,k为最佳值。用实际故障信号验证了方法的可行性,为VMD方法的研究提出了一种新的思路

不同发育阶段社会隔离对成年大鼠潜伏抑制的影响

&nbsp;观察青春期和成年早期社会隔离对不同发育阶段大鼠的潜伏抑制的影响，并进一步探讨其神经机制。实验1：雄性Wistar大鼠在PND38-51天被给予2周的社会隔离，然后分别在PND52天及恢复2周群居后的PND66天，即青春期和成年早期，测定潜伏抑制；实验2：雄性Wistar大鼠在PND58-71天被给予2周的社会隔离，然后分别在PND72天及恢复2周群居后的PND86天，测定潜伏抑制；实验3：利用实验1的社会隔离模式，然后在PND52天及PND66天测定其伏隔核的多巴胺水平。实验发现：1）青春期社会隔离不影响青春期大鼠的潜伏抑制及伏隔核多巴胺水平，但能诱发成年早期大鼠的潜伏抑制缺失及伏隔核内多巴胺水平的提高；2）成年早期的社会隔离不影响大鼠的潜伏抑制。实验结果表明：与成年早期社会隔离相比，青春期社会隔离能诱发大鼠的潜伏抑制缺失，且此行为异常直至成年期后才表现出来，伏隔核的多巴胺可能和参与这一过程的神经机制相关

古尔班通古特沙漠区大沙鼠对荒漠植物群落的扰动效应

2006年5月,调查了大沙鼠洞区和对照区植物种类组成、盖度、密度、地上生物量,研究了大沙鼠对古尔班通古特沙漠植物群落物种组成和植被结构的影响。使用Mann-Whitney U检验表明,洞区植物种数(16.1)显著高于对照区(13.8)(Z=2.436,P<0.05);洞区半灌木种数(0.8)显著低于对照区(1.9)(Z=3.442,P<0.01)。受大沙鼠扰动影响,大沙鼠洞区植被平均盖度(2.40%±2.30%)显著低于对照区(14.46%±6.82%)(Z=3.63,P<0.01);大沙鼠洞区地上植物生物量(6.52g.m-2±6.30g.m-2)显著低于对照区(23.3g.m-2±12.85g.m-2,Z=3.708,P<0.01)。大沙鼠洞区Simpson指数(0.75±0.10,n=10)和Shannon-Wiener指数(0.78±0.12,n=10)显著高于对照区Simpson指数(0.61±0.16)和Shannon-Wiener指数(0.60±0.16)(t=2.362,P<0.05;t=2.948,P<0.01)。结果表明:大沙鼠的掘洞、采食行为能够提高古尔班通古特沙漠1年生植物的物种多样性,并导致半灌木衰败。洞区的植物群落在一定程度上显现出次生演替的特征

Effects of Pubertal and Adult Social Isolation on the Latent Inhibition of Rats

&nbsp;观察青春期和成年早期社会隔离对不同发育阶段大鼠的潜伏抑制的影响，并进一步探讨其神经机制。实验1：雄性Wistar大鼠在PND38-51天被给予2周的社会隔离，然后分别在PND52天及恢复2周群居后的PND66天，即青春期和成年早期，测定潜伏抑制；实验2：雄性Wistar大鼠在PND58-71天被给予2周的社会隔离，然后分别在PND72天及恢复2周群居后的PND86天，测定潜伏抑制；实验3：利用实验1的社会隔离模式，然后在PND52天及PND66天测定其伏隔核的多巴胺水平。实验发现：1）青春期社会隔离不影响青春期大鼠的潜伏抑制及伏隔核多巴胺水平，但能诱发成年早期大鼠的潜伏抑制缺失及伏隔核内多巴胺水平的提高；2）成年早期的社会隔离不影响大鼠的潜伏抑制。实验结果表明：与成年早期社会隔离相比，青春期社会隔离能诱发大鼠的潜伏抑制缺失，且此行为异常直至成年期后才表现出来，伏隔核的多巴胺可能和参与这一过程的神经机制相关。</p

非正交弧线齿面齿轮齿面设计及可视化

设计了一种新型非正交弧线齿面齿轮，其以弧线齿圆柱齿轮为假想刀具，包络展成面齿轮工作齿面及过渡曲面，并在Matlab中得到面齿轮的数学模型，推导出非正交弧线齿面齿轮全齿面齿面方程，并通过Matlab编程实现了齿面可视化，为后续对非正交弧线齿面齿轮的研究奠定了理论基础

Error of large-eddy simulation in the wall pressure fluctuation of a turbulent channel flow

We analyze the error of large-eddy simulation (LES) in wall pressure fluctuation of a turbulent channel flow. To separate different sources of the error, we conduct both direct numerical simulations (DNS) and LES, and apply an explicit filter on DNS data to obtain filtered DNS (FDNS) data. The error of LES is consequently decomposed into two parts: The first part is the error of FDNS with respect to DNS, which quantifies the influence of the filter operation. The second part is the difference between LES and FDNS induced by the error of LES in velocity field. By comparing the root-mean-square value and the wavenumber-frequency spectrum of the wall pressure fluctuation, it is found that the inaccuracy of the velocity fluctuations is the dominant source that induces the error of LES in the wall pressure fluctuation. The present study provides a basis on future LES studies of the wall pressure fluctuation. (C) 2021 The Authors. Published by Elsevier Ltd on behalf of The Chinese Society of Theoretical and Applied Mechanics