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31.
Probabilistic estimation of dietary exposure to DON, including its acetylated derivatives, and type B trichothecenes from cereals and cereal-based products in Chinese populations was investigated in the current work. Different cut-offs as proposed Maximum levels (MLs) for DON in various raw cereals and/or cereal-based foods were assessed based on the risk assessment results. Occurrence data was documented from 31 provinces of China over the year 2010–2013. Food consumption data was obtained from the National Diet and Nutrition Survey conducted in 2002. Dietary exposure was implemented by Monte Carlo (MC) simulations and Bootstrap resampling. The exposure distributions were specified as percentiles with confidence intervals (95% CIs) and compared with the group provisional maximum tolerable daily intake (PMTDI) of 1 μg/kg bw/day and the group acute reference dose (ARfD) of 8 μg/kg bw/day for DON and its acetylated derivatives. Results indicate that 75% of children and 90% of the general population and the adults are under the group PMTDI value, while 99% of the three populations are under ARfD value. However, under the assumptions of the proposed cut-offs, the P99.9 percentiles would decrease significantly. The probabilistic assessment in this study indicated that high-end exposure to DON and its derivatives should be concerned, especially for children. Rigorous formulation of maximum limits for DON and its derivatives in the relevant foodstuffs combined with increased monitoring should be considered as an effective way to reduce risk.  相似文献   
32.
董箫欢  吴璟 《建筑与文化》2016,(12):120-122
特殊教育学校(以下简称特教学校)的康复训练领域在近十几年间有了长足的发展。感觉统合作为一种新型的有效康复训练手段,今后会被特教学校广泛采用,为了保证其康复治疗效果,感统教室应具有一定的规定性。而现有的《特殊教育学校建筑设计规范》JGJ76-2003中尚未对感统教室有明确的设计要求。浙江省的特殊教育发展较为成熟,省内的特教学校已普遍设置了感统教室,具有一定的代表性。因此本文将调研浙江省内既有的感统教室,梳理其现状特点,对其设计要点进行总结。期望本文的研究成果能为规范的修编及今后感统教室的建设提供有益的借鉴或指导。  相似文献   
33.
本文分析了我国纺织品服装批发市场的现状和存在的问题,并以实例描述了纺织品服装批发市场的发展演变过程及入世后我国纺织品服装批发市场在新的竞争环境中的发展趋势。  相似文献   
34.
汉语韵律边界的声学实验研究   总被引:2,自引:4,他引:2  
本文以带有韵律标注的语料库ASCCD为基础,从语音信号分析的角度,研究了汉语普通话韵律间断模式在语音的时长、基频和音强等三个方面的表现特征,并在大量统计分析的基础上建立了识别分类的决策树模型,实验证明,这些特征能较好地描述朗读话语的韵律间断模式。  相似文献   
35.
本文以面向敏捷企业的智能制造执行系统(I-MES)为研究对象,采用多Agent技术作为系统的实现形式,对系统的多Agent组织结构、系统中多Agent间的通信和协作机制以及多Agent的基于事件和周期的动态调度策略等理论问题和关键技术进行了研究,针对可集成制造执行系统中最常见的资源冲突问题,提出了一种基于多Agent合作的冲突消解模型;在此基础上针对敏捷环境下传统的制造执行系统的不足,以烟草企业这类流程性工艺企业为背景,基于多代理技术,构建了一个基于多代理具有开放性、集成性、动态性、敏捷性和可互操作的敏捷制造智能执行系统,  相似文献   
36.
Autonomous robots must be designed to function in real-world domains. These domains are characterized by uncertainty, yet little work has been done to quantify the effects of uncertainty on goal satisfaction. Our research on simulated repair robots indicates that different types of uncertainty have fundamentally different relationships to plan success. This paper investigates the impacts of sensor inaccuracies, exogenous events and failures in both motion and gripper operations. Extensive simulations provide the basis for mathematical models of the relationship between these types of uncertainties and plan success. In addition, the impact of current heuristics such as ‘retry on failure’, and ‘tell me three times’ is investigated. Concluding that even low levels of uncertainty can significantly impact goal satisfaction in a stimulated repair robot domain and that repeated attempts provide significant improvement in plan success rates in the face of uncertainty.  相似文献   
37.
The presented work is part of a larger research program dealing with developing tools for coupling biogeochemical models in contaminated landscapes. The specific objective of this article is to provide researchers with a data porting tool to build hexagonal raster using information from a rectangular raster data (e.g. GIS format). This tool involves a computational algorithm and an open source software (written in C). The method of extending the reticulated functions defined on 2D networks is an essential key of this algorithm and can also be used for other purposes than data porting. The algorithm allows one to build the hexagonal raster with a cell size independent from the geometry of the rectangular raster. The extended function is a bi-cubic spline which can exactly reconstruct polynomials up to degree three in each variable. We validate the method by analyzing errors in some theoretical case studies followed by other studies with real terrain elevation data. We also introduce and briefly present an iterative water routing method and use it for validation on a case with concrete terrain data.  相似文献   
38.
Among Fusarium mycotoxins, deoxynivalenol (DON) is the most common contaminant in case of cereals and cereal-based foods in Hungary. In this study, Hungarian wheat (n = 305), maize (n = 108), wheat flour (n = 179) and pasta (n = 226) samples were analysed (N = 818). The samples were collected during 2008–2015 in Hungary. Applied methods of analysis were enzyme-linked immunosorbent assay and liquid-chromatography coupled with a mass spectrometer. Results were compared and evaluated with Hungarian weather data. Among cereal samples, in 2011, wheat was contaminated with DON (overall average ± standard deviation was 2159 ± 2818 µg kg?1), which was above the maximum limit (ML). In case of wheat flour and pasta, no average values above ML were found during 2008–2015, but higher DON contamination could be observed in 2011 as well (wheat flour: 537 ± 573 µg kg?1; pasta: 511 ± 175 µg kg?1).  相似文献   
39.
紫花苜蓿生物活性与应用的研究现状   总被引:2,自引:0,他引:2  
紫花苜蓿的茎、叶中含有多种营养素及未知生长因子,紫花苜蓿次生代谢物具有多种独特的生物活性,如抗氧化、抑菌等。本文简述了紫花苜蓿叶蛋白、皂苷、类黄酮、膳食纤维等主要活性成分及其营养保健作用,并谈及紫花苜蓿活性成分营养保健的应用前景。  相似文献   
40.
Five commonly consumed pulses, Mah (Vigna mungo), Green mung (Vigna radiata), Arhar (Cajanas cajan), Masur (Lens esculantus), and Moth (Vigna aconitifolia), were studied for their total phenolic content and antioxidant activity after germination (12 and 24 h) and pressure cooking. Arhar had the highest total phenolic content (6.71 mg ferulic acid/g flour) whereas Moth had the least (1.54 mg/g). All pulses, except Moth, showed a significant decrease in total phenolic content after germination. The antioxidant activity of the pulses varied from 10.61 to 36.38% (DPPH radical scavenging activity), which significantly decreased with germination in all pulses except Moth. The total phenolic content highly correlated with the antioxidant activity in the pulses. Cooking lowered the total phenolic content by 10–45% and antioxidant activity by 27–68% in the control and germinated pulses.  相似文献   
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