检索结果-南通市图书馆

Fluoroacetate in plants - a review of its distribution, toxicity to livestock and microbial detoxification

Journal of Animal Science and Biotechnology 2017年第4期8卷 813-823页

作者： lex ee xiang leong Shahjalal Khan Carl K. Davis Stuart E. Denman Chris S. McSweeney School of Chemistry and Molecular Bioscience University of Queensland St Lucia 4072 QLD Australia. School of Agriculture and Food Sciences University of Queensland St Lucia 4072 QLD Australia CSIRO Agriculture and Food Queensland Bioscience Precinct St Lucia 4072 QLD Australia

Fluoroacetate producing plants grow worldwide and it is believed they produce this toxic compound as a defence mechanism against grazing by herbivores. Ingestion by livestock often results in fatal poisonings, which causes significant economic problems to commercial farmers in many countries such as Australia, Brazil and South *** approaches have been adopted to protect livestock from the toxicity with limited success including fencing,toxic plant eradication and agents that bind the toxin. Genetically modified bacteria capable of degrading fluoroacetate have been able to protect ruminants from fluoroacetate toxicity under experimental conditions but concerns over the release of these microbes into the environment have prevented the application of this ***, a native bacterium from an Australian bovine rumen was isolated which can degrade fluoroacetate. This bacterium, strain MFA1, which belongs to the Synergistetes phylum degrades fluoroacetate to fluoride ions and acetate. The discovery and isolation of this bacterium provides a new opportunity to detoxify fluoroacetate in the rumen. This review focuses on fluoroacetate toxicity in ruminant livestock, the mechanism of fluoroacetate toxicity,tolerance of some animals to fluoroaceate, previous attempts to mitigate toxicity, aerobic and anaerobic microbial degradation of fluoroacetate, and future directions to overcome fluoroacetate toxicity.

关键词： Aerobic Anaerobic Degradation Dehalogenase Fluoroacetate 1080 Synergistetes TCA Toxicity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effectiveness of mindfulness-based interventions on the well-being of healthcare workers:a systematic review and meta-analysis

引用

General Psychiatry 2024年第3期37卷 335-344页

作者： Natasha Yixuan Ong Finn Jing Jie Teo Jane Zi Ying ee Chun En Yau Julian Thumboo Hiang Khoon Tan Qin xiang Ng NUS Yong Loo Lin School of Medicine National University of SingaporeSingapore Health Services Research Unit Singapore General HospitalSingapore SingHealth Duke-NUS Medicine Academic Clinical Programme Duke-NUS Medical SchoolSingapore Singhealth Duke-NUS Global Health Institute Singapore Duke Global Health Institute Duke UniversityDurhamNorth CarolinaUSA Division of Surgery and Surgical Oncology Singapore General HospitalSingapore Saw Swee Hock School of Public Health National University of Singapore and National University Health SystemSingapore

Background Growing evidence attests to the efficacy of mindfulness-based interventions(MBIs),but their effectiveness for healthcare workers remains *** To evaluate the evidence for MBIs in improving healthcare workers’psychological *** A systematic literature search was conducted on Medline,Embase,Cumulative Index for Nursing and Allied Health Literature,PsycINFO and Cochrane Central Register of Controlled Trials up to 31 August 2022 using the keywords‘healthcare worker’,‘doctor’,‘nurse’,‘allied health’,‘mindfulness’,‘wellness’,‘workshop’and‘program’.Randomised controlled trials with a defined MBI focusing on healthcare workers and quantitative outcome measures related to subjective or psychological well-being were eligible for inclusion.R V.4.0.3 was used for data analysis,with the standardised mean difference as the primary outcome,employing DerSimonian and Laird’s random effects *** of Recommendations,Assessment,Development and Evaluation framework was used to evaluate the quality of ***’s Risk of Bias 2 tool was used to assess the risk of bias in the included *** A total of 27 studies with 2506 participants were included,mostly from the USA,involving various healthcare *** such as stress reduction programmes,apps,meditation and training showed small to large effects on anxiety,burnout,stress,depression,psychological distress and job strain outcomes of the *** effects were also seen in self-compassion,empathy,mindfulness and ***,long-term outcomes(1 month or longer postintervention)varied,and the effects were not consistently *** MBIs offer short-term benefits in reducing stress-related symptoms in healthcare *** review also highlights limitations such as intervention heterogeneity,reduced power in specific subgroup analyses and variable study quality.

关键词： nurse sustained workers

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Distortion-aware beamforming design for multi-beam satellite communications with nonlinear power amplifiers

引用

Science China(Information Sciences) 2024年第6期67卷 359-369页

作者： xiang XIAO Li YOU Kezhi WANG Xiqi GAO National Mobile Communications Research Laboratory Southeast University Purple Mountain Laboratories Department of Computer Science Brunel University London

Hardware components can cause different impairments, including power amplifier(PA) nonlinearities, which inevitably impact the system performance of satellite communications(SATCOM). In this work, we consider a multi-beam SATCOM downlink system and investigate the distortion-aware beamforming scheme with the characteristics of PA non-linearities. Notably, we aim to maximize the resource efficiency(RE), defined as the weighted sum of energy efficiency(ee) with spectral efficiency(SE), to obtain a flexible ee-SE tradeoff while accounting for the characteristics of PA distortion and the total power *** that the optimization objective is a sum of ratios and the high non-convexity involved in constraints,we propose an efficient approach that exploits the quadratic transformation, the Lagrange multiplier method,and the gradient ascent approach to handle this issue. Simulation results demonstrate the effectiveness of the distortion-aware beamforming approach in achieving the ee-SE tradeoff and exhibit a substantial RE performance gain over the conventional approach with ideal linear PAs assumed at the satellite transmitters.

关键词： multi-beam satellite communications nonlinear power amplifier energy and spectral efficiency tradeoff resource efficiency robust beamforming

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Inherently Chiral and Symmetrical Heteroatom-Doped Zigzag-Type Hydrocarbon Belts

引用

CCS Chemistry 2024年第5期6卷 1198-1210页

作者： Xue-Yuan Wang Xin-Yu Zhang Shuo Tong Qing-Hui Guo Mei-Ling Tan Cheng-Jun Li Mei-xiang Wang Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084

hydrocarbon belts due to their potential applications in carbon *** contrast,heteroatomembedded zigzag hydrocarbon belts as advanced design strategies with fascinating structures and desirable,unique properties have remained largely unexplored,and inherently chiral ones are ***,we report the synthesis of a diversity of symmetric and highly enantiopure inherently chiral O-and N-doped zigzag-type hydrocarbon belts starting from strainless macrocycles based on fjord-stitching *** readily available pertriflated resorcin[6]arene underwent partial hydrolyses and intramolecular S_(N)Ar reactions to form a calix[3](9H-xanthene)derivative and a prochiral half-belt *** transformations of calix[3](9H-xanthene)into C_(3v)-symmetric molecular belts were achieved by closing the rest of the fjords with triple intramolecular S_(N)Ar reactions and Yamamoto homo coupling reactions,as well as palladiumcatalyzed intermolecular acridination reactions with primary *** prochiral half-belt underwent enantioselective desymmetrizative mono-acridination to afford an inherently chiral N,O_(4)-bridged pseudo-belt with an enantiomeric excess(ee)value of>99%under the catalysis of Pd(OAc)_(2)and(R)-*** closure reactions of the pseudo-belt produced diverse heteroatom-inlayed zigzag-type hydrocarbon belts of inherent ***,we showed the unique cavity structures of the belts and demonstrated interesting chiroptic properties of the inherently enantiopure chiral *** research opens the door for the exploration of novel and sophisticated symmetric and inherently chiral molecular nanobelt structures with outstanding physical and chemical properties,as well as potential applications.

关键词： zigzag-type molecular belt heterocycle chiroptical property fjord-stitching strategy resorcinarene

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

地震产品与信息可视化平台设计与实现

引用

中国地震 2024年第1期40卷 234-241页

作者：杨斌董翔刘钦山西省地震局太原030021 中国地震台网中心北京100045

地震信息可视化表达可有效地减轻地震灾害损失。地震产品与信息可视化平台基于Javaee开发,后端采用SpringMVC,前端采用REAT框架,业务信息通过ActiveMQ消息中间件传输,实现了多个地震信息产出平台的数据自动汇集。面向不同用户对象时,通... 详细信息

地震信息可视化表达可有效地减轻地震灾害损失。地震产品与信息可视化平台基于Javaee开发,后端采用SpringMVC,前端采用REAT框架,业务信息通过ActiveMQ消息中间件传输,实现了多个地震信息产出平台的数据自动汇集。面向不同用户对象时,通过内容重构形成用户所需地震信息产品,并采用匹配的可视化手段,实现各类数据资源面向不同用户对象的可视化集成展示,提升了地震产品与信息的服务效能。

关键词：地震信息可视化系统设计

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

国际人道法与人权法对使用致命武力攻击儿童兵的限制

引用

人权研究 2024年第2期 66-91页

作者：李想武汉大学法学院

为保护儿童权利免遭武装冲突所害,国际法禁止征募儿童、使用儿童直接参加敌对行动。然而,国际人道法的现有规则默认参战儿童可以像成年战斗员那样被视为合法攻击目标,并且没有对使用致命武力攻击儿童兵施加限制。这不仅与前述禁止性规... 详细信息

为保护儿童权利免遭武装冲突所害,国际法禁止征募儿童、使用儿童直接参加敌对行动。然而,国际人道法的现有规则默认参战儿童可以像成年战斗员那样被视为合法攻击目标,并且没有对使用致命武力攻击儿童兵施加限制。这不仅与前述禁止性规范的保护目标背道而驰,而且也忽视了国际法对儿童生命权的特别尊重与保护。就对儿童兵使用不加限制的致命武力而言,当国际人道法和人权法均具备可适用性时,仅在前者被确立为特别法因而优先于后者时,其合法性才得以证成。分析表明,特别法原则无法证成不加限制的致命武力的合法性。妥善的做法是限制对儿童兵使用致命武力,当具体情况表明致命武力为明显不必要时,应优先考虑俘虏或非致命方法。采取这一立场既可以最大程度地保护武装冲突中儿童的权利,也不至于妨碍交战双方追求军事胜利。

关键词：儿童兵国际人道法国际人权法特别法原则生命权

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

基于CNN计算局部复杂度的可逆信息隐藏算法

引用

计算机学报 2024年第4期47卷 776-789页

作者：胡润文项世军李晓龙欧博暨南大学信息科学技术学院/网络空间安全学院广州510632 北京交通大学信息科学研究所北京100044 湖南大学信息科学与工程学院长沙410082

在可逆信息隐藏领域,选择较小的预测误差有助于减少信息嵌入过程引起的失真.现有选择方法主要计算预测误差的局部复杂度,将信息嵌入到局部复杂度小的预测误差中.这些局部复杂度计算方法只使用部分相邻像素计算局部复杂度,且计算方法与... 详细信息

在可逆信息隐藏领域,选择较小的预测误差有助于减少信息嵌入过程引起的失真.现有选择方法主要计算预测误差的局部复杂度,将信息嵌入到局部复杂度小的预测误差中.这些局部复杂度计算方法只使用部分相邻像素计算局部复杂度,且计算方法与预测部分使用的预测器无关,因此其选择性能有待提高.本文提出了一种基于CNN的局部复杂度计算方法LCCN,该方法与预测部分的预测器相关,可以使用更多的相邻像素计算局部复杂度,提高局部复杂度与预测误差的相似性.与现有的局部复杂度计算方法相比,所提LCCN利用了CNN的多感受野特性和深度学习的全局优化能力,能使用更多相邻像素计算局部复杂度,从而选择更多数值较小的预测误差,提高嵌入算法性能.此外,我们还提出了一种适用于LCCN的两阶段RDH方案,该方案可以将LCCN应用于多种嵌入方法.实验结果表明,与现有的几种局部复杂度计算方法相比,本文所提方法在标准测试图像和Kodak数据集上嵌入性能更好,在基于LPVO的嵌入技术中,本文所提LCCN模型嵌入10000bits后图像Lena的PSNR为62.09dB,分别高于LV、FV、ee和LAE算法1.05dB、1.02dB、0.78dB和0.90dB.与现有的先进RDH算法比较,本文所提LCCN模型在不同图像上均取得较好效果.

关键词：可逆信息隐藏局部复杂度深度学习卷积神经网络预测误差隐私计算

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

基于硬件损伤与离散相移的IRS辅助MU-MISO通信系统鲁棒能效优化算法

引用

电子学报 2024年第6期52卷 1832-1841页

作者：熊迎香徐勇军陈前斌黄崇文重庆邮电大学通信与信息工程学院重庆400065 浙江大学信息与电子工程学院浙江杭州310027

针对现有工作仅考虑理想信道状态信息(Channel State Information,CSI)与硬件调控能力导致在实际系统中用户传输中断过高的问题,该文综合考虑不完美CSI、有限相移调控、硬件损伤的影响,提出了一种基于智能反射面(Intelligent Reflecting... 详细信息

针对现有工作仅考虑理想信道状态信息(Channel State Information,CSI)与硬件调控能力导致在实际系统中用户传输中断过高的问题,该文综合考虑不完美CSI、有限相移调控、硬件损伤的影响,提出了一种基于智能反射面(Intelligent Reflecting Surface,IRS)辅助的鲁棒能效优化算法.考虑基站最大发射功率与IRS离散相移约束及差异化用户传输速率需求,基于高斯CSI误差模型和加性硬件损伤模型,将基站主动波束成形与IRS被动相移优化问题建模为含不确定性参数的多变量耦合能效最大化问题.考虑波束向量与相移矩阵的耦合性,利用交替优化策略将原问题转化为主动波束子问题和离散相移子问题.利用伯恩斯坦不等式、丁克尔巴赫方法及连续凸近似将波束子问题转化为凸优化问题求解;基于求解的主动波束向量,利用罚函数法和投影定理求解离散相移子问题.仿真结果表明,与传统非鲁棒算法相比,所提算法能效性能提升15.8%,平均中断概率间隙达86.7%.

关键词：智能反射面能效优化鲁棒性

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Competitive sorption between 17α-ethinyl estradiol and bisphenol A/4-n-nonylphenol by soils

引用

Journal of Environmental Sciences 2013年第6期25卷 1154-1163页

作者： Jianzhong Li Lu Jiang Xi xiang Shuang Xu Rou Wen xiang Liu School of Environment Tsinghua University

The sorption of 17α-ethinyl estradiol （ee2）, bisphenol A （BPA）, and 4-n-nonylphenol （NP） in single systems and the sorption of ee2 with different initial aqueous concentrations of BPA or NP were examined using three soils. Results showed that all sorption isotherms were nonlinear and fit the Freundlich model. The degree of nonlinearity was in the order BPA （0.537-0.686）〉 ee2 （0.705-0.858）〉 NP （0.875-0.0.951） in single systems. The isotherm linearity index of ee2 sorption calculated by the Freundlich model for Loam, Silt Loam and Silt increased from 0.758, 0.705 and 0.858, to 0.889, 0.910 and 0.969, respectively, when BPA concentration increased from 0 to 1000 μg/L, but the effect of NP was comparably minimal. Additionally, ee2 significantly suppressed the sorption of BPA, but insignificantly suppressed that of NE These findings can be attributed to the difference of sorption affinity of ee2, NP and BPA on the hard carbon （e.g., black carbon） of soil organic matter that dominated the sorption in the low equilibrium aqueous concentration range of endocrine-disrupting chemicals （EDCs）. Competitive sorption among EDCs presents new challenges for predicting the transport and fate of EDCs under the influence of co-solutes.

关键词： competitive sorption 17α-ethinyl estradiol endocrine-disrupting chemicals distributed reactivity model black carbon

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

基于eeI体验模型的农村旅游信息导向系统设计——以泰安里峪村为例

引用

设计 2024年第8期37卷 99-101页

作者：梁斌向飞帆泰山学院艺术学院燕山大学艺术与设计学院

以设计艺术的手法改善农村旅游信息视觉导向系统的建设,提升新农村旅游环境品质。将eeI体验模型引入到里峪村旅游信息视觉导向系统进行设计与运用研究中,从体验模式的视角出发,以建设标识系统、视觉导向地图、导视系统装置、信息技术交... 详细信息

以设计艺术的手法改善农村旅游信息视觉导向系统的建设,提升新农村旅游环境品质。将eeI体验模型引入到里峪村旅游信息视觉导向系统进行设计与运用研究中,从体验模式的视角出发,以建设标识系统、视觉导向地图、导视系统装置、信息技术交互体验和完善公共设施等作为设计手段,改善农村导向系统设计。基于eeI体验模型的泰安里峪村导视系统的策划,进一步丰富了新农村旅游资源,改善了农村旅游品质,为乡村振兴、打造特色村镇以及发展新农村旅游产业提供了具体可行的办法。

关键词： eeI体验模型农村旅游信息视觉导向系统泰安里峪村设计策略

来源：

维普期刊数据库

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：