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61.
在世界范围内,由真菌毒素造成的经济损失估计达数十亿美元,给人类和动物带来安全风险。粮食中真菌毒素的预防可以通过食品加工过程中进行真菌毒素的消减处理。在过去几十年里,虽然发表的科技论文中报道了大量真菌毒素防控措施,但实际生产往往需要更容易实施的、简单易行的建议和指导方针。欧洲和东南亚在真菌毒素处理到数据分析、风险评估到污染防控、差异分析到流通途径等方面可以做到相互协作,互相补充。欧洲和东南亚政府及相关行业必须在综合考虑地域、农业系统和不同国家消费者偏好的背景下,寻求平衡食品安全和地区贸易二者关系,协同管控食品供应链。以谷物为例,加工过程包括初级加工(谷物清理和碾磨操作)和二次加工(如烘焙过程中的发酵和烘烤),欧洲尤其关注烘焙食品安全性及全麦面包生产工艺对呕吐毒素的影响。结合农业、咖啡工业和科学研究人员的专业知识及亚洲咖啡生产者的具体情况,重点关注东南亚地区咖啡中赭曲霉毒素A污染问题。在农场环境中减少真菌毒素的措施给咖啡农民带来了较大的挑战,包括在规范种植农场模式下咖啡生产者和消费者之间社会经济效益和个人行为模式的相关影响因素。随着世界变得更加全球化,食品和饲料供应链也变得日趋复杂,因此,需要制定更全面的策略来确保食品供给及品质安全。 相似文献
62.
Iara Rocha Antunes Pereira Bresolin Igor Tadeu Lazzarotto Bresohn Priscila Gava Mazzola Elias Basile Tambourgi 《化学与化工:英文版》2014,(3):270-277
This work aimed the incorporation of the enzyme bromelain from pineapple peel into dermatological bases for potential therapeutic application. The enzyme was incorporated into Lanette cream and lotion, as well as Carbopol gel and Chemyunion cream and lotion, at a concentration of 0.5% (w/w). These bases were subjected to centrifugation test and accelerated stability test during 90 days at 25 ℃(with and without sunlight), 37 ℃ and 4 ℃, in order to evaluate bromelain stability in dermatological bases. Total protein content and enzymatic activity were measured. The bases were stable as its organoleptic characteristics (appearance, color, smell and sensitivity to touch) only when kept at 4 ℃ with activity remaining 95.5%, 84,9%. 77.7%, 73.8% and 72.3%, alter 90 days of testing in Carbopol gel, Lanette and Chemyunion cream, and Lanette and Chemyunion lotion, respectively. Based on the results, it was possible to incorporate bromelain into dermatological bases, and the activity was well preserved when these bases were kept in refrigerator at 4 ℃. 相似文献
63.
Distributed System-level diagnosis allows the fault-free components of a fault-tolerant distributed system to determine which components of the system are faulty and which are fault-free. The time it takes for nodes running the algorithm to diagnose a new event is called the algorithm's latency. In this paper we present a new distributed system-level diagnosis algorithm which presents a latency of O(log N) testing rounds, for a system of N nodes. A previous hierarchical distributed system-level diagnosis algorithm, Hi-ADSD, presents a latency of O(log
2
N) testing rounds. Nodes are grouped in progressively larger logical clusters for the purpose of testing. The algorithm employs an isochronous testing strategy that forces all fault-free nodes to execute tests on clusters of the same size each testing round. This strategy is based on two main principles: a tested node must test its tester in the same round; a node only accepts tests according to a lexical priority order. We present formal proofs that the algorithm's latency is at most 2log N – 1 testing rounds and that the testing strategy of the algorithm leads to the execution of isochronous tests. Simulation results are shown for systems of up to 64 nodes. 相似文献
64.
International Regulations of Propolis Quality: Required Assays do not Necessarily Reflect their Polyphenolic‐Related In Vitro Activities 下载免费PDF全文
Raquel Bridi Gloria Montenegro Gabriel Nuñez‐Quijada Ady Giordano Maria Fernanda Morán‐Romero Isaac Jara‐Pezoa Hernán Speisky Elias Atala Camilo López‐Alarcón 《Journal of food science》2015,80(6):C1188-C1195
Propolis has been proposed as a polyphenolic‐rich natural product potentially able to be used for human consumption or even for medicinal proposes. To guarantee a minimum phenolic and flavonoid content and as consequence of their related‐biological activities, international requirements of propolis quality are commonly applied. In this work we assessed phenolic and flavonoid contents of propolis; the antioxidant capacity (toward peroxyl radicals and hypochlorous acid); the ability to generate nitric oxide (NO); and, finally the antimicrobial activity of 6 propolis samples from the VI region of Chile. Our results show that the total phenolic and flavonoid content of propolis samples are not always in agreement with their polyphenolic‐associated in vitro activities. For example, P03 and P06 samples showed the lowest (25 ± 4 GAE/g propolis) and the highest (105 ± 3 GAE/g propolis) total phenolic content, respectively. This was in agreement with flavonoid content and their Oxygen Radical Absorbance Capacity (ORAC) activity. However, this dependence was not observed toward HOCl, NO release and antimicrobial activity. Based on our results, we consider that, in order to guarantee the antioxidant or antimicrobial in vitro effects, the international regulations of propolis quality should contemplate the convenience of incorporating other simple analytical test such as ORAC or antimicrobial tests. 相似文献
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This paper deals with the reliability of a renewable three-unit system under preventive maintenance activity. The Laplace transform of the reliability function and the mean lifetime of the system have been obtained under the assumption that the failure times, repair times, inspection times and maintenance times are random variables having different distributions. Some special cases also have been obtained. 相似文献
69.
Numerous factors related to health and diseases have been studied in relation to cognitive function. It has been shown that across the life span, systemic medical diseases can negatively impact cognitive function. Factors that influence the development of medical diseases, such as poor health habits, biological risk factors, hormones, genetic factors, exposure to environmental toxins, and certain treatments for disease, can also have an adverse effect on cognitive function. Conversely, factors such as high levels of education, good health habits, and some treatments for disease can be protective. Included in this special section are 6 empirical articles that examine the relation of health or disease to cognitive function. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
Wayne C. Westerman David P. M. Northmore John. G. Elias 《Analog Integrated Circuits and Signal Processing》1997,13(1-2):167-184
We describe neuromorphic, variable-weight synapses onartificial dendrites that facilitate experimentation with correlativeadaptation rules. Attention is focused on those aspects of biologicalsynaptic function that could affect a neuromorphic network'scomputational power and adaptive capability. These include sublinearsummation, quantal synaptic noise, and independent adaptationof adjacent synapses. The diffusive nature of artificial dendritesadds considerable flexibility to the design of fast synapsesby allowing conductances to be enabled for short or for variablelengths of time. We present two complementary synapse designs:the shared conductance array and the self-timed synapse. Bothsynapse circuits behave as conductances to mimic biological synapsesand thus enable sublinear summation. The former achieves weightvariation by selecting different conductances from an on-chiparray, and the latter by modulating the length of time a constantconductance remains activated. Both work with our interchip communicationsystem, virtual wires. For the present purpose of comparing variousadaptation mechanisms in software, synaptic weights are storedoff chip. This simplifies the addition of quantal weight noiseand allows connections from different sources to the same dendriticcompartment to have independent weights. 相似文献