薄皮甜瓜新品种“陕甜一号”的选育

薄皮甜瓜新品种“陕甜1号”是以优良高代甜瓜自交系M33为母本、D4-1为父本配制的一代杂交种,该品种全生育期70 d左右,果实发育期25 d,果实长阔梨形,充分成熟时果面白亮有黄晕,果肉纯白,肉质脆爽香甜,可溶性固形物含量13％～15％.单瓜重500～650 g,667 m2产量3 800 kg.植株长势旺,抗病性强,适应性广,2010年通过陕西省农作物品种委员会审定.     

青春双歧杆菌凝固型酸奶研制及选择性培养基比较

以鲜牛奶、白砂糖为主要原料,以青春双歧杆菌、保加利亚乳杆菌、嗜热链球菌为发酵剂,制成营养保健的青春双歧杆菌凝固型酸奶.通过试验确定了青春双歧杆菌凝固型酸奶最佳工艺为:白砂糖8%,接种量3%,保加利亚乳杆菌:嗜热链球菌:青春双歧杆菌=1:1:4,发酵4h.结合MRS培养基和LM-MRS培养基可以对青春双歧杆菌凝固型酸奶中...     

肉鸡血浆VLDL浓度的选择效应——对产蛋性能的影响

以零世代和一世代高、低脂系肉鸡为素材 ,个体记录高、低脂系母鸡产蛋性能 ,屠宰测定零世代 54周龄母鸡腹脂重 (率 ) ,探讨肥度性状与产蛋性能的关系 ,并研究零世代、一世代高、低脂系产蛋性能选择效应。结果表明 :在限饲条件下 ,腹脂重 (率 )与开产日龄、产蛋量表型相关很弱。腹脂重 (率 )与蛋重呈负表型相关趋势 ;零世代高、低脂系产蛋性能差异不显著。一世代低脂系比高脂系早开产 6.7d,低脂系 4 0周龄和 54周龄产蛋量显著高于高脂系 ,表明对血浆 VLDL浓度的选择使产蛋性能产生了有益的间接反应     

利用共享对象实现基于Web的远程教学实时课件

本文介绍了Macromedia Flash Media Server(FMS)服务器平台中的共享对象的概念,通过实例详细描述了如何利用共享对象制作实时教学课件,并应用在基于Web的远程教学软件之中.     

Adverse impact of industrial animal agriculture on the health and welfare of farmed animals

Industrial animal agriculture is grounded in the concept of maximizing productivity and profit. Selective breeding for maximum productivity in one characteristic of the animal (e.g. milk yield in cows, or breast meat in broiler chickens) has resulted in genotypes and phenotypes that may predispose the animals to poor health and welfare. The conditions in which these individuals are kept may also frustrate many inherited behaviors that they are strongly motivated to perform. In order to curb the resulting harmful aberrant behaviors, such as feather‐pecking in chickens, we sometimes resort to mutilating the animals. In many places chickens are routinely de‐beaked by means of a hot metal guillotine. Compassion in World Farming (an international organization that promotes the humane treatment of farm animals) believes that it is unethical to treat sentient beings in such ways. We have a duty to respect farm animals' sentience by providing them with housing conditions that take their needs and wants into account, and by reverting to the use of dual‐purpose, slower‐growing breeds that have the potential for good welfare. Alternatives to current farming practices are available, and we owe it to the animals, and to our consciences, to pursue them.     

丝状真菌遗传转化系统研究进展

近年来,丝状真菌的分子生物学研究发展非常迅速,尤其是丝状真菌遗传转化研究取得了长足的进展。对丝状真菌遗传转化系统的最新研究进展进行综述,主要包括丝状真菌的转化方法、选择标记、转化系统的应用等。     

Michigan Mute Swan Management: A Case Study to Understand Contentious Natural Resource Management Issues

U.S. state fish and wildlife agencies have responded to perceived ecological and social threats posed by mute swans by implementing population control strategies. In Michigan, some stakeholder groups have vocally opposed particular control activities. To better understand and characterize key aspects of the underlying media dialogue about mute swan management in Michigan, one factor in the development of public perceptions about wildlife issues, we conducted a qualitative content analysis of Michigan-specific online news articles. Results revealed tensions between stakeholder groups about management priorities were rooted in differing ideas about healthy social and ecological systems, appropriate wildlife behavior, and the acceptability of lethal control (i.e., shooting living birds). Characterizing which stakeholder groups aligned with particular arguments might allow managers to tailor and direct messaging to specific audiences.     

Temporal changes in ascendance and in‐season exploitation of Atlantic salmon,Salmo salar,inferred by a video camera array

Abstract Weekly exploitation rates of Atlantic salmon, Salmo salar L., in the River Utsjoki, Finland, were estimated from catch reports during the 2003, 2004, 2006 and 2007 seasons, and recordings of all Atlantic salmon ascending the river using a submerged video camera array. In all years, mean weekly fishing mortality rates were significantly higher in June than July to August, with a falling trend throughout the fishing season. Owing to overlap in size between one‐sea‐winter (1SW) and multi‐sea‐winter (MSW) salmon, the estimated fishing mortality rates were based on all sea‐age categories combined. By the second week in June, 18.3–34.7% of large salmon (only MSW) had ascended, compared with 2.2–6.4% of small salmon (1SW and some MSW). Indirectly, the earlier start of ascent of large salmon to River Utsjoki indicated that in‐river fishing mortality of MSW salmon is higher than for 1SW salmon. A later opening of the fishing season may be used to reduce the in‐river fishing mortality, especially for the MSW component.     

Effect of different methods for the induction of spermiation on semen quality in European eel

Five hormonal treatments with human chorionic gonadotropin (hCG) were tested for the induction of maturation and spermiation in male farmed eels. The main aim was to optimize previously used hormonal treatments to achieve shorter induction treatments, longer spermiation periods and/or higher sperm quality. Fish treated for just 3 weeks (treatment E) or until the onset of spermiation (treatment C) showed the worst results, while the treatment consisting of weekly administration of 1.5 IU hCG g^?1 fish (treatment A) induced the highest percentage of spermiating males, the highest number of sperm samples and sperm volumes and densities similar to the rest of the treatments (B: half hormone dosage, or D: biweekly administration). Evaluation of the sperm quality was performed by computer‐assisted sperm analysis (CASA), considering the percentage of total motile spermatozoa, the percentage of fast and medium‐velocity spermatozoa, as well as different motility parameters. Sperm samples from A‐D groups showed between 44% and 54% motile spermatozoa, and between 10% and 15% fast spermatozoa, while samples from E‐treated males showed 0% motile cells. No significant differences were found in the spermatozoa straight line velocity (VSL), curvilinear velocity (VCL) or the angular velocity (VAP), neither spermatozoa beating cross frequency (BCF) between A–D groups.     

9种常用杀螨剂对巴氏新小绥螨和二斑叶螨的毒力及毒力选择性研究

为使化学防治和保护利用捕食螨的生物防治措施相协调, 实现以螨治螨, 采用叶片残毒法分别测定了甘肃省保护地常用的9种杀螨剂对巴氏新小绥螨和二斑叶螨的LC50, 计算出各药剂的益害生物毒性选择指数(TSR)。供试药剂的毒性选择指数大小依次为：毒死蜱＞螺螨酯＞哒螨灵＞炔螨特＞唑螨酯＞阿维菌素＞三唑锡＞甲氰菊酯＞噻螨酮。其中, 毒死蜱和螺螨酯的毒性选择指数分别为10.864 1和9.361 3, 对巴氏新小绥螨和二斑叶螨均有较高的正向选择性, 毒死蜱和螺螨酯可优先用于生产中害虫(螨)的防治, 同时最大限度地保护了捕食螨, 实现对害虫(螨)化学防治和生物防治的相互协调。