浙江千岛湖地区苦槠叶片昆虫取食状类型和取食强度研究

选择千岛湖地区不同大小岛屿为样地,对苦槠(Castanopsis sclerophylla)叶片虫食状类型和取食强度进行了研究.结果表明,千岛湖地区苦槠叶片昆虫取食状类型为16种,但取食频率不同.取食频率和取食部位对叶片危害程度的分析结果显示,缘食状、掏食状、顶食状、阴面食状和叶中脉状对植物叶片的影响更大.16种取食状中,缘食状和顶食状、缘食状和阴面食状之间呈极显著正相关(P＜0.01),缘食状与大孔状、顶食状与大孔状、顶食状与掏食状、阳面食状与阴面食状之间呈显著正相关(P＜0.05).苦槠叶片被昆虫取食的频率为84%,但绝大多数受害程度低.     

华山松松茎象幼虫的危害及其防治研究

华山松松茎象是南岳景区松树上新发现的一种重要害虫,该虫严重危害华山松和黑松.本文介绍了其幼虫的取食危害特点及防治方法.该虫幼虫取食华山松和黑松的韧皮部,同时取食新鲜的松脂,越冬后的幼虫仅靠取食新鲜松脂就能正常发育,并化蛹、羽化.单株虫口数量与松树树干基部直径呈明显正相关,即树干基部直径在10.0~20.0 cm 、20.1~25.0 cm 、25.1~35.0 cm之间的松树,平均单株有虫数量分别为1.0头株-1、1.98头株-1和3.30头.株-1.在5~10月间,采用人工清除幼虫的方法可有效地控制该虫的危害,采用化学药剂防治该虫效果不明显.     

留兰香栽培管理与香油提取技术

作者介绍了留兰香的生长习性,从水土保持开发性治理的角度探讨了留兰香在红壤侵蚀区的栽培管理技术,并对留兰香油提取技术进行了对比研究。     

广州市居民食品砷摄入的健康风险评价

从暴露途径来看,食物是人体砷暴露的主要途径之一。从饮食结构来看,广州市居民膳食主要来源于谷类食品,同时鱼虾类总体平均摄入量约为全国总体平均摄入量的2倍。因此,在分析广州市市场大米和海鲜这2种典型食品中砷含量的基础上对广州市居民食品砷摄入的健康风险进行了评价。分析了广州市场上的26种不同品牌的大米中的总砷含量,其含量范围为0.082～0.171μg·g~(-1),平均浓度为(0.127±0.027)μg·g~(-1),满足绿色食品大米标准(≤0.40μg·g~(-1))。在14种鱼虾蟹贝类海鲜中的砷含量分析基础上,计算得出广州市场上鱼类中总砷的平均含量为0.488μg·g~(-1),虾蟹贝类中总砷的平均含量为3.44μg·g~(-1),相比较国内外,广州市场鱼虾蟹中砷的含量整体处于中间水平。最后综合文献调研中其他主要食品中砷的含量,计算得出广州市成人通过食品每日摄入总砷的量为5.08μg·kg~(-1)BW·d~(-1)。建议日常饮食需要特别控制每日海鲜的摄入量,尤其是砷含量较高的濑尿虾、红虾及红蟹、花蟹。     

Metal Interactions in carcinogenesis†

Mixed exposures to a number of metallic compounds may give rise to a carcinogenic response in humans.

An interaction between occupational exposure to arsenic and cigarette smoking has been documented epidemiologically. A multiplicative effect was indicated concerning the occurrence of lung cancer when both of the exposures were present. Several experimental studies have been reported in the literature concerning interactions between benzo(a)pyrene and Fe₂O₃ as well as some other metallic compounds like Ni₃S₂, PbO, MgO and TiO₂ in relation to respiratory carcinogenicity. There is also limited evidence of a positive interaction between arsenic trioxide and benzo(a)pyrene. Particles containing V and Ni were obtained from the flue gases of power plants burning heavy fuel oil. Such particles were not carcinogenic themselves but enhanced the carcinogenicity of benzo(a)pyrene even more efficiently than Fe₂O₃.

Increased dietary selenium intakes can decrease the carcinogenicity of several organic carcinogens in animals and dietary zinc can effectuate both enhancement and inhibition of carcinogenicity depending on dietary concentration.     

The behavioral ecology of cannibalism in cane toads (<Emphasis Type="Italic">Bufo marinus</Emphasis>)

Laboratory studies show that predatory cane toads (Bufo marinus) exhibit specialized toe-luring behavior that attracts smaller conspecifics, but field surveys of toad diet rarely record cannibalism. Our data resolve this paradox, showing that cannibalism is common under specific ecological conditions. In the wet–dry tropics of Australia, desiccation risk constrains recently metamorphosed toads to the edges of the natal pond. Juvenile toads large enough to consume their smaller conspecifics switch to a primarily cannibalistic diet (67% of prey biomass in stomachs of larger toads). Cannibalistic attack was triggered by prey movement, and (perhaps as an adaptive response to this threat) small (edible-sized) toads were virtually immobile at night (when cannibals were active). Smaller metamorphs were consumed more frequently than were larger conspecifics. The switch from insectivory to cannibalism reflects the high dry season densities of small conspecifics (in turn, due to desiccation-imposed constraints to dispersal) and the scarcity of alternative (insect) prey during dry weather. Our study pond (102 m in circumference) supported >400 juvenile toads, which consumed many metamorphs over the course of our study. Toads appear to be low-quality food items for other toads; in laboratory trials, juvenile toads that fed only on conspecifics grew less rapidly than those that ate an equivalent mass of insects. This effect was not due to parotoid gland toxins per se. Thus, cane toads switch to intensive cannibalism only when seasonal precipitation regimes increase encounter rates between large and small toads, while simultaneously reducing the availability of alternative prey.     

User Perceptions and Attitudes on Sustainable Urban Transport among Young Adults: Findings from Copenhagen,Budapest and Karlsruhe

Abstract

This paper addresses the relevance of the demand side for the achievement of sustainable transport in urban areas. The underlying thesis is that a better understanding of user habits, perceptions and attitudes with its specific dynamics is essential for a successful design of targeted transport policies. In line with this, the paper at hand is based on research that aims at improving the knowledge of urban-transport-related habits and attitudes of young adults. The results of three interview meetings that were held in Karlsruhe, Budapest, and Copenhagen with participants aged between 20 and 30 are presented. Background of the interviews is a range of studies that indicate that young people in urban areas seem to be less interested in cars than the generation before. And indeed, the interview meetings reveal that participants had a rather pragmatic attitude towards transport modes. They wished a transport system that is flexible, convenient and cheap. Despite many differences, most participants showed rather positive attitudes towards policies supporting alternatives to car-based transport. However, it will be crucial for policy shaping to what extent the observed behaviour patterns and attitudes will persist over time.     

Evoking trust in the nutrition counselor: why should we be trusted?

The virtue of trust is often spoken of as central to the work of dietitians working in nutrition counseling, especially in the context of disordered eating/eating disorders nutrition therapy. Indeed, dietitians are purported to be the most trusted source of information on nutrition and food by professional associations such as Dietitians of Canada. Here trust is explored through educational, relational, and virtue theory in order to elucidate trusts meaning and relevance to dietitians work and interactions with each other, including the general public. If dietitians are to continue to be trusted during times of skepticism in expert knowledge, reflexivity, active contestation, and moral testing in the context of our socio-political milieu need be employed so that we as a profession may respond to clients in respectful, authentic, meaningful ways; practices worthy of our trust.     

苏州旅游强市与旅游要素建设--从吃、住、行三要素说起

苏州要从旅游大市提升到旅游强市，必须强化旅游吃、住、行三要素建设。苏邦菜应借鉴成功经验，改良传统名菜，重建“吃在苏州”的格局。饭店既要满足基本接待需求，更要强化会议、商务功能，加快科技化、信息化、网络化建设，健全休闲娱乐功能。以提高苏州旅游接待业的总体水平和整体吸引力。为打开旅游交通这一瓶颈，应增加营运车辆，在线路安排和旅游集散中心建设上精心策划，调动民间资本参与旅游交通建设。     

关于革除滥食野生动物陋习决定的解读

为了预防公共卫生风险、保护生态环境,全国人大常委会于2020年2月通过了《关于全面禁止非法野生动物交易、革除滥食野生动物陋习、切实保障人民群众生命健康安全的决定》(以下简称《决定》)。《决定》通过黑名单和白名单明确了禁食野生动物范围和可食动物范围、人工繁育的特殊情形,从猎捕、交易、运输、食用环节全过程开展监管和协调执法。本文深入剖析了《决定》出台的意义和目的、《决定》的主要内容和亮点,并提出了贯彻落实《决定》的措施建议。建议科学制定国家级畜禽遗传资源保护名录和国家水产品遗传资源保护名录;建立全国统一的执法信息平台和违法举报平台,建立执法考核制度和问责办法;持续提供相应保障;加强国际合作和公众参与。