Positive and negative effects of widespread badger culling on tuberculosis in cattle

Human and livestock diseases can be difficult to control where infection persists in wildlife populations. For three decades, European badgers (Meles meles) have been culled by the British government in a series of attempts to limit the spread of Mycobacterium bovis, the causative agent of bovine tuberculosis (TB), to cattle. Despite these efforts, the incidence of TB in cattle has risen consistently, re-emerging as a primary concern for Britain's cattle industry. Recently, badger culling has attracted controversy because experimental studies have reached contrasting conclusions (albeit using different protocols), with culled areas showing either markedly reduced or increased incidence of TB in cattle. This has confused attempts to develop a science-based management policy. Here we use data from a large-scale, randomized field experiment to help resolve these apparent differences. We show that, as carried out in this experiment, culling reduces cattle TB incidence in the areas that are culled, but increases incidence in adjoining areas. These findings are biologically consistent with previous studies but will present challenges for policy development.     

《圣经》对英美语言的影响

《圣经》是基督教的经典,是希伯来民族文化的宝贵遗产。基督教文化深深地渗透在英美国家的语言中,《圣经》对英语词汇、习语和格言的形成和发展起了不可估量的作用。     

世界牛邮票赏析

以收集到的142枚世界牛邮票为线索,阐释世界常见的牛类群、牛与人类的物质关联、牛的文化内涵。从物质层面,千百年来,人类依赖牛耕地种田,靠牛拉车载物,养牛改善膳食营养,牛在人类的生产、生活中发挥了无可替代的作用;从文化层面,牛稳健刚毅、吃苦耐劳、无私奉献、忠诚淳朴的精神也逐渐深入人心,形成了蕴藉深厚,蔚为大观的世界牛文化。     

High incidence area of cattle cancer with a possible interaction between an environmental carcinogen and a papilloma virus.

Cattle in upland areas of Scotland and northern England are substantially more prone to alimentary cancer than those of the immediately neighbouring lowlands, and epidemiological evidence implicates a combination of papilloma virus and bracken in the aetiology of the disease. Here Professor Jarrett outlines the circumstantial case against these agents and discusses its implications.     

抗结核治疗对肺结核患者血清中细胞因子的影响研究

目的：研究抗结核治疗对肺结核患者血清中细胞因子的影响。方法：选择肺结核患者70名作为研究对象,依据患者治疗情况将其划分成抗结核治疗组和对照组。结果：血清中细胞在治疗组中以胞质和胞膜为主呈淡棕黄色变化,在对照组中以胞质和胞膜为主呈棕黄、褐黄色变化。治疗组血清中的细胞因子和对照组相比差异具有非常显著性(P<0.01);治疗组血清中的细胞因子明显低于对照组,差异具有统计学意义(P<0.05)。抗结核治疗组血清中的细胞因子和对照组相比有非常显著性差异(P<0.01)。治疗组血清中的细胞因子mRNA表达结果明显低于对照组,差异具有统计学意义(P<0.05)。治疗组血清中细胞因子mRNA表达结果均低于对照组,差异无统计学意义(P>0.05)。血清中IFN-γ含量随菌量负荷的增加而增加,痰液中IFN-γ含量随菌量负荷的增加而降低,相关性存在统计学意义(P<0.01)。血清TNF-α含量随菌量负荷的增加而降低,血清中TNF-α含量随菌量负荷的增加而增加,相关性具有非常显著性(P<0.01)。血清中IL-10含量随菌量负荷的增加而增加,相关性具有非常显著性(P<0.01)。结论：抗结核治疗对肺结核患者血清中细胞因子具有重要作用。     

英国企业参与职业教育初探

我国职业教育在长期的发展过程中遇到许多难题，造成这些难题的主要原因是企业没有积极参与职业教育。英国企业参与职业教育的历史悠久，研究和借鉴英国企业参与职业教育的保障措施、主要途径及发展态势，对于促进我国企业参与职业教育具有重要的现实意义。     

非金属夹杂物对弹簧钢局部腐蚀的影响

Certain inclusions in high-strength 60Si2Mn–Cr spring steel result in poor resistance to localized corrosion. In this work, to study the effect of inclusions on the localized corrosion behavior of spring steel, accelerated corrosion tests were performed by immersing spring steel in 3wt% FeCl₃ solution for different times. The results show that severe corrosion occurred in areas of clustered CaS inclusions. Sulfide inclusions containing Ca and Mg induced the strongest localized corrosion susceptibility. For the case of (Ca,Mn,Mg)S inclusions, the ability to induce localized corrosion susceptibility is ranked as follows: MgS > CaS > MnS. Moreover, CaS, (Ca,Mn)S, and (Ca,Mn,Mg)S inclusions were mainly responsible for inducing environmental embrittlement.     

局域表面等离子体研究进展

阐述了局域表面等离子体特性,金属纳米粒子的常用制备方法,以及不同形状、尺寸等因素对局域表面等离子体光谱和灵敏度的影响,分析了表面增强拉曼散射的增强因子与金属纳米粒子的等离子共振波长和拉曼激发波长之间的关系,介绍了局域表面等离子体在生物传感方面的应用.     

局域表面等离子体研究进展

阐述了局域表面等离子体特性,金属纳米粒子的常用制备方法,以及不同形状、尺寸等因素对局域表面等离子体光谱和灵敏度的影响,分析了表面增强拉曼散射的增强因子与金属纳米粒子的等离子共振波长和拉曼激发波长之间的关系,介绍了局域表面等离子体在生物传感方面的应用.     

Effect of nonmetallic inclusions on localized corrosion of spring steel

Certain inclusions in high-strength 60 Si2Mn–Cr spring steel result in poor resistance to localized corrosion. In this work, to study the effect of inclusions on the localized corrosion behavior of spring steel, accelerated corrosion tests were performed by immersing spring steel in 3 wt% FeCl_3 solution for different times. The results show that severe corrosion occurred in areas of clustered Ca S inclusions. Sulfide inclusions containing Ca and Mg induced the strongest localized corrosion susceptibility. For the case of(Ca,Mn,Mg)S inclusions, the ability to induce localized corrosion susceptibility is ranked as follows: Mg S Ca S Mn S. Moreover, Ca S,(Ca,Mn)S, and(Ca,Mn,Mg)S inclusions were mainly responsible for inducing environmental embrittlement.     

超数排卵与采卵对供体牛产奶量及繁殖性能影响的实验研究

目前,超数排卵和胚胎移植技术是良种奶牛快速扩繁的最佳手段和途径,但有人担心超数排卵、采卵等不良刺激会对供体牛的产奶量和繁殖性能产生不良影响.2003-2004年对90头供体牛超数排卵和采卵后的繁殖情况和产奶量进行了记录,并与未经超排的成乳牛和育成牛进行比较,发现超数排卵与采卵对供体牛的产奶量和繁殖性能均无显著影响.     

Effect of British hunting ban on fox numbers

Pressure to ban the hunting of foxes with hounds in Britain has fuelled debate about its contribution to the control of fox populations. We took advantage of a nationwide one-year ban on fox-hunting during the outbreak of foot-and-mouth disease (FMD) in 2001 to examine this issue and found that the ban had no measurable impact on fox numbers in randomly selected areas. Our results argue against suggestions that fox populations would increase markedly in the event of a permanent ban on hunting.     

沙能杂种山羊的生长发育研究

本研究对英国沙能山羊的杂种,进行了长达十数年的系列研究,不仅测定了一、二、三代杂种羊从初生到成年8个主要阶段的生长发育特点,而且将处于同等饲养条件下的父、母系品种作为对照,进行了同样测定,从而揭示了各代杂种羊的生长发育规律和体重体尺等性状的遗传特点。     

A Study on the Uniqueness of British Political System

这篇论文旨在研究英国政治体制的特点。作者将从君主制和行政体制两方面阐述英国政治体制的独特性。在文中,作者将对比英国政治体制与中美政治体制的异同。通过这篇文章,读者能很好的理解英国政治体制的独特性。     

对象中的指针对封装的影响

提出了在C++编程环境中把对象内的指针区别对待的思想.对于内部含有指针的对象,根据对象与其中的指针所指向内容的关系,可以把指针分为内含式和外联式两类.内含式指针所指向的内容是对象的一个组成部分,外联式指针则描述对象与外部的联系.C++程序设计环境并不支持这样的划分,需要设计人员自己处理.对内含式的指针必须设计相应的拷贝构造函数,并且对赋值运算符进行重载,否则有可能破坏对象的封装特性.     

几类图的关联图的边色数

给出了图Wn、Fn及(～F)m(n)的关联图I(Wn)、I(Fn)、I((～F)m(n))的边色数.