Are social embeddedness associated with food risk perception under media coverage?

Traceability system has received wide attention in solving food safety issues, via which food information could be tracked back to producer/farmers. Consumers need to obtain this information from producers or social networks, trust in the information,and consequently assess perceived risks, especially when food scandals are exposed to the media. In this study, we introduce the social embeddedness theory to understand how consumers' social activities affect their risk perceptions on traceable food. Specifically, we investigate how risk perceptions are predicted by the interpersonal relationships, organizational level and social-level relationships. Results show that the interpersonal relationships were associated with lower levels of risk perceptions, while organizational and social relationships impacted consumer's risk perceptions at middle and higher levels,respectively. Results also show that the "ripple effect" extended to effect of risk events with negative information, however,did not exist for the group exposed to positive information. Potential food safety implications have been proposed to identify for effective risk mitigation under media coverages.     

台湾食品安全监管法律制度及其借鉴意义

我国大陆近来频发的食品安全问题暴露出食品监管法律制度的缺陷,亟待解决。台湾地区的食品安全监管制度相对大陆来说比较完善,有比较健全的监管机构和法律制度、强有力的社会团体监督以及严厉的违法处罚措施。目前,我国大陆食品安全监管缺乏完善的食品安全认证和法律制度,应该借鉴台湾食品安全的监管经验,通过完善食品安全立法制度和法律制度,发挥食品行业协会的作用,以及制定严格的违法处罚措施来健全大陆的食品安全监管法律体系。     

Errorless discrimination, autoshaping, and conditioned inhibition

Pigeons were exposed to a discriminated autoshaping procedure in which brief presentation of a green light on a key was always followed by food whereas presentation of a vertical white line on the key was never followed by food. Pigeons acquired an errorless discrimination by pecking reliably in the presence of the green light but never in the presence of the line. The line inhibited pecking in later tests: when the white line was paired with food, key peck acquisition was retarded; and when the white line was superimposed on the green background, responding was suppressed.     

Neural correlate of behavioral plasticity in command neurons of Pleurobranchaea

Food stimuli normally excite the command neurons of Pleurobranchaea that cause feeding. In contrast, the same food stimuli selectively inhibit these neurons in specimens that have been trained to suppress feeding and withdraw from food by means of an avoidance conditioning paradigm consisting of paired food and conditional shock. Food stimuli excite the feeding command neurons of yoked control specimens exposed to unpaired food and shock, but inhibit the feeding command neurons of untrained specimens that have been satiated with food. These results suggest that the command neurons serve as a neural locus at which an animal's behavior is modulated by past experiences. These results also establish a neural correlate of behavioral plasticity, in the form of synaptic inhibition of the command neurons.     

提高河北省食用农产品质量安全水平的对策

总结了近几年河北省在食用农产品质量安全方面所做的工作和取得的主要成效,分析了省内外曝光的食用农产品质量安全事件的发生原因,就进一步提高河北省食用农产品质量安全水平提出了对策建议。     

Maternal influence in learning by observation in kittens

Kittens who observed their mothers perform a stimulus-controlled response (lever pressing to a visual stimulus for food) acquired and discriminated that response sooner than kittens who observed a strange female cat's performance. Kittens exposed to a trial and error condition never acquired the response. Initial differences in attentiveness to demonstrator performances disappeared by the second day. "Altruism" (food sharing) and other forms of social behavior were exhibited by both mother and stranger demonstrators.     

苏北农村饮食状况和食品安全意识——基于苏北3县的调查研究

以苏北3县为样本,调查了农村的饮食状况和消费者的食品安全意识并进行了分析,阐述了苏北农村食品安全隐患存在的原因,揭示了农村市场食品安全监管的漏洞,提出了在新农村建设的新形势下,改善苏北农村食品安全现状的对策和建议。     

于桥水库周边农业生态环境补偿制度研究

介绍了农业生态补偿机制的重要性,提出于桥水库周边农业生态环境补偿机制的重点内容,即鼓励农民发展绿色食品和有机食品,投资新建禽畜养殖污物无害化处理设施,控制地面裸露,重视培育和管理生态林,减少库区水质污染等,并指出在补偿机制的制定和实行过程中应注意的几点问题。     

艾比湖卤虫对不同粒径饵料藻的摄食选择性研究

为研究卤虫培养中饲料藻的利用状况,以艾比湖卤虫Artemia parthenogenetica Aibi Lake为对象,研究了艾比湖卤虫在3种不同粒径开口饵料藻(湛江等鞭金藻Isochrysis zhanjiangensis、杜氏盐生藻Dunaliella salina、青岛大扁藻Platymonas helgolondica)驯化培养下,对不同饵料藻的摄食率及对食物的摄食选择性。结果表明:艾比湖卤虫对等鞭金藻的最大摄食率为30.6×10~4cells/(ind.·h),对盐藻的最大摄食率为16.6×10~4cells/(ind.·h),对扁藻的最大摄食率为6.7×10~4cells/(ind.·h),即饵料粒径越小,卤虫的摄食率越高;混合饵料试验中,不论是2种藻混合还是3种藻等密度混合,卤虫对开口饵料藻的摄食率显著高于其他饵料藻(P0.05),以盐藻为开口饵料驯化的卤虫尤为明显,对盐藻的摄食率极显著高于其他组(P0.01),即卤虫在开口饵料驯化后,对开口饵料存在明显的习惯性摄食;卤虫的食物选择性指数结果显示,混合饵料中卤虫均是优先选择等鞭金藻,其次选择盐藻,最后是扁藻。本研究结果可为卤虫培养中饵料藻的选取提供参考。     

多溴联苯醚对鲫鱼组织DNA损伤及p53蛋白表达的影响

以鲫鱼(Carassius auratus)为试验材料,研究了经不同浓度的2,2’,4,4’-四溴联苯醚(PBDE-47)和十溴联苯醚(PBDE-209)暴露后,鲫鱼体内DNA损伤产物8-羟基脱氧鸟苷(8-OHdG)的含量及p53蛋白的水平。结果表明,采用浓度为0.10～5.00mg·L-1的PBDE-47和10.0～50.0mg·L-1的PBDE-209处理鲫鱼20d,除了0.10mg·L-1PBDE-47和10.0mg·L-1PBDE-209浓度组的8-OHdG和p53蛋白含量与对照组相比无显著差异(P>0.05),其余各浓度组的8-OHdG和p53蛋白含量均随PBDE-47和PBDE-209浓度增加而逐渐上升,呈显著的相关关系(P<0.01),且8-OHdG和p53蛋白之间也呈显著的正相关。说明PBDE-47和PBDE-209对鲫鱼组织的DNA产生了损伤,具有遗传毒性影响。     

Teosinte glume architecture 1: A Genetic Locus Controlling a Key Step in Maize Evolution

Teosinte, the probable progenitor of maize, has kernels that are encased in hardened fruitcases, which interfere with the use of the kernels as food. Although the components of the fruitcase are present in maize, their development is disrupted so that the kernels are not encased as in teosinte but exposed on the ear. The change from encased to exposed kernels represents a key step in maize evolution. The locus that largely controls this morphological difference between maize and teosinte, teosinte glume architecture 1, is described and genetically mapped.     

纳米氧化锌对人正常肝细胞HL-7702的毒性作用研究

[目的]研究食品添加剂纳米氧化锌对人正常肝细胞HL-7702的毒性作用。[方法]采用不同浓度（5、10、25、50、100、250μg/ml）的纳米氧化锌对HL-7702细胞进行染毒;光学显微镜下观察细胞的形态学变化;采用MTT法检测纳米氧化锌对HL-7702细胞生长活性的影响;应用荧光探针活性氧检测技术检测细胞内活性氧（ROS）的生成情况。[结果]纳米氧化锌可引起HL-7702细胞形态变化;MTT检测显示,纳米氧化锌对HL-7702细胞的生长活性具有明显的抑制作用;荧光探针活性氧检测发现,染毒后HL-7702细胞内ROS的生成量增加。[结论]纳米氧化锌作为一种新型锌源,建议控制其添加量或使用量。     

紫甘薯红色素与其他同类色素的稳定性比较

对紫甘薯红色素与紫葡萄、紫苏、黑米、紫李和黑豆等其它五种植物所含红色素进行了理化稳定性的比较研究.结果表明,紫甘薯红色素具有与其它几种红色素相似的理化稳定性,其热稳定性与紫米相似,但优于其它色素;光稳定性最强;对金属离子和食品添加剂等的稳定性则不明显.     

豆腐凝胶成型机理研究进展

豆腐凝胶形成过程是豆腐加工关键环节。其形成机制目前普遍认为是大豆贮藏蛋白(包括大豆球蛋白和β-伴大豆球蛋白)在加热条件下分子内部疏水集团暴露,聚集形成大豆蛋白聚集体;聚集体在盐离子、氢质子或酶等凝固剂作用下,形成致密、有序和稳定三维蛋白网络结构,呈宏观豆腐凝胶。豆腐凝胶形成受多种因素影响。本文综述大豆蛋白组成、豆浆热处理工艺和凝固剂使用等因素对豆腐品质和凝胶形成机理影响,旨在为豆腐凝胶成型理论探讨、加工工艺参数选择和新产品开发提供新思路。     

Supplemental lighting stimulates growth and lactation in cattle

Sixteen hours of light daily (114 to 207 lux) increased weight gains and milk yield 10 to 15% in Holstein cattle in comparison with cattle exposed to natural-length photoperiods (39 to 93 lux) of 9 to 12 hours. The weight gain was accomplished without increased consumption of feed. Manipulation of supplemental light may thus cause dramatic increases in food supplies from animals.     

盐度对口虾蛄假溞状幼体存活和摄食的影响

在实验室条件下,观测了盐度对口虾蛄Oratosquilla oratoria Z9～Z11期假溞状幼体存活和摄食的影响.设置盐度骤变和渐变两组试验,骤变试验以27为基础盐度,将假溞状幼体直接放入盐度为51、48、45、42、39、36、33、30、24、21、18、15、12、9的海水中;渐变试验盐度分别从24和33开始,每隔12h降低(低盐渐变)和升高(高盐渐变)一次盐度值,变化幅度为1,直至口虾蛄假溞状幼体全部死亡.以体长为5.19～8.91 mm(平均体质量为0.058 g)的鲜活糠虾作为饵料.试验结果表明:当盐度骤变到18～36时,口虾蛄假溞状幼体比较适应,24h时成活率在77.8％以上;盐度骤变情况下,24h半致死盐度为15.94和41.13;假溞状幼体适应骤变盐度的低盐度和高盐度极限分别为12和48,适应渐变盐度的低盐度和高盐度极限分别为6和54;当盐度低于15或高于45时,口虾蛄假溞状幼体基本不摄食,盐度为27、30和33时,假溞状幼体的摄食量明显高于其它盐度组.综合考虑成活率和摄食两方面的因素,培育口虾蛄Z9～Z11期假溞状幼体的适宜盐度为27 ～33.     

Insecticides: Effects on Cutthroat Trout of Repeated Exposure to DDT

Cutthroat trout were periodically exposed to p, pp-DDT, in acetone solution or in the food. Excessive mortality occurred only in lots treated with high concentrations of DDT, probably as a result of decreased resistance to nonspecific stressors. Surviving fish in these lots were significantly larger than those in the control lot, or in the lots treated with low concentrations of DDT. The number and volume of eggs produced was not reduced by DDT, but mortality among sac fry appeared to be highest in the lots treated with high concentrations. The data suggest that the sublethal concentrations of DDT ordinarily encountered in the environment are unlikely to damage a fishery.     

中国粮食宏观调控的成效和问题及改革建议

粮食市场化改革以来,我国逐渐形成了以价格干预机制和储备制度为核心的粮食宏观调控体系,切实保护了种粮农民利益、保持了粮食市场稳定、维护了国家粮食安全。宏观调控机制在发挥重要作用的同时,逐步暴露出一些问题,突出表现在:市场功能的作用不断弱化、调控政策的保障力和执行力出现下降的趋向,以及政策调整的步伐滞后于粮食形势、市场化形势、宏观调控形势的发展。我们对此必须予以重视,及时纠正偏差、加快改革完善,充分发挥市场机制的基础性作用,把市场机制与宏观调控有机地结合起来,不断加强和改善宏观调控,切实提高宏观调控的综合效能。     

毒死蜱在叶菜上的残留及降解动态分析

以芥菜为例,对露地条件下生产的叶菜类蔬菜中毒死蜱的残留及降解规律进行研究.结果表明,毒死蜱在芥菜中的降解速率在喷药后5 d内呈直线下降趋势,第5 d后降解趋于平稳;毒死蜱在芥菜中的残留量随着喷施浓度的增加而增加;以毒死蜱最高推荐浓度和低于最高推荐浓度3倍的药液量进行喷洒,在7 d安全间隔期及安全间隔期满2d后,毒死蜱在芥菜中的残留量均高于国家标准.因此,建议对毒死蜱的推荐使用浓度、施用次数、安全间隔期等做进一步的试验研究,以确保蔬菜的食用安全.     

Drug-resistant Salmonella in the United States: an epidemiologic perspective

Salmonellosis poses a health problem of large proportions in the United States. Annually, it accounts for more than 40,000 reported cases, 500 deaths, and financial costs well in excess of $50 million. Antimicrobial resistance is increasing in Salmonella strains, a finding that has important public health implications. Although the chain of transmission of the bacteria is often complex, combined epidemiologic and laboratory studies with the use of new methods in molecular biology make it possible to trace antimicrobial-resistant salmonellae to their primary source--foods of animal origin. These studies suggest that the antimicrobial drugs to which food animals are exposed provide selective pressure that leads to the appearance and persistence of resistant strains.