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21.
Food fraud, including the more defined subcategory of economically motivated adulteration, is a food risk that is gaining recognition and concern. Regardless of the cause of the food risk, adulteration of food is both an industry and a government responsibility. Food safety, food fraud, and food defense incidents can create adulteration of food with public health threats. Food fraud is an intentional act for economic gain, whereas a food safety incident is an unintentional act with unintentional harm, and a food defense incident is an intentional act with intentional harm. Economically motivated adulteration may be just that-economically motivated-but the food-related public health risks are often more risky than traditional food safety threats because the contaminants are unconventional. Current intervention systems are not designed to look for a near infinite number of potential contaminants. The authors developed the core concepts reported here following comprehensive research of articles and reports, expert elicitation, and an extensive peer review. The intent of this research paper is to provide a base reference document for defining food fraud-it focuses specifically on the public health threat-and to facilitate a shift in focus from intervention to prevention. This will subsequently provide a framework for future quantitative or innovative research. The fraud opportunity is deconstructed using the criminology and behavioral science applications of the crime triangle and the chemistry of the crime. The research provides a food risk matrix and identifies food fraud incident types. This project provides a starting point for future food science, food safety, and food defense research. PRACTICAL APPLICATION: Food fraud, including the more defined subcategory of economically motivated adulteration, is a food protection threat that has not been defined or holistically addressed. The terrorist attacks of September 11, 2001, led to the development of food defense as an autonomous area of study and a new food protection discipline. As economically motivated adulteration grows in scope, scale, and awareness, it is conceivable that food fraud will achieve the same status as an autonomous concept, between food safety and food defense. This research establishes a starting point for defining food fraud and identifying the public health risks.  相似文献   
22.
Addition of t-butylcyclohexano-15-crown-5 (tBC-15C5) induces a synergistic effect in the extraction of Mn2+ ion with didodecylnaphthalenesulfonic acid (HDDNS). This synergism is the result of the inner-sphere complexation of the crown ether to the manganese(II) ion. The formation of this complex, first suggested by distribution studies, has been confirmed by FTIR experiments. The C-O-C stretching bands for the crown ether ligand shift to lower frequency when Mn2+ ion is extracted into a CC14 solution of HDDNS and tBC15C5. A similar C-O-C Btretching band is observed for the crystalline complex [Mn(15C5 ) (Bu3CS03)2] (where 15C5 = 15-crown-5 and Bu = n-butyl).Formation of analogous complexes is not observed for Fe3+, co2+,N2+,cu2+, or zn2+ under similar conditions.  相似文献   
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24.
S. M. Monroe and K. L. Harkness (see record 2005-02750-005) reviewed the empirical evidence supporting R. M. Post's (see record 1992-43211-001) kindling model, which suggests the 1st episode of depression is more likely to be preceded by major stressors than are subsequent episodes. Their review highlighted the diverse interpretations of Post's premise in the current literature and the changes in research methods that have contributed to this interpretive shift. The authors conducted a meta-analysis (N=13 studies) to test Post's premise that integrated early and recent research and examined potential moderators. A proportion difference effect size was used. Results indicated that 1st onsets of depression were more likely than recurrences to be preceded by severe life events, supporting Post's premise. The moderator analyses suggested that support may be most evident in patient samples and may vary according to age and gender, with less support for Post's premise evidenced in younger samples and in women. Although these results are preliminary, as the analysis included a small number of studies, they suggest that future research should further examine factors that influence the stress-depression relationship with successive recurrences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
25.
We describe a novel fungal expression system which utilizes the Quorn myco-protein fungus Fusarium graminearum A 3/5. A transformation system was developed for F. graminearum and was used to introduce the coding and regulatory regions of a trypsin gene from Fusarium oxysporum. The protein was efficiently expressed, processed and secreted by the recombinant host strain. In addition, the promoter and terminator of the F. oxysporum trypsin gene have been successfully utilized to drive the expression of a cellulase gene from Scytalidium thermophilum and a lipase gene from Thermomyces lanuginosus in F. graminearum.  相似文献   
26.
Existing and emerging methods in computational mechanics are rarely validated against problems with an unknown outcome. For this reason, Sandia National Laboratories, in partnership with US National Science Foundation and Naval Surface Warfare Center Carderock Division, launched a computational challenge in mid-summer, 2012. Researchers and engineers were invited to predict crack initiation and propagation in a simple but novel geometry fabricated from a common off-the-shelf commercial engineering alloy. The goal of this international Sandia Fracture Challenge was to benchmark the capabilities for the prediction of deformation and damage evolution associated with ductile tearing in structural metals, including physics models, computational methods, and numerical implementations currently available in the computational fracture community. Thirteen teams participated, reporting blind predictions for the outcome of the Challenge. The simulations and experiments were performed independently and kept confidential. The methods for fracture prediction taken by the thirteen teams ranged from very simple engineering calculations to complicated multiscale simulations. The wide variation in modeling results showed a striking lack of consistency across research groups in addressing problems of ductile fracture. While some methods were more successful than others, it is clear that the problem of ductile fracture prediction continues to be challenging. Specific areas of deficiency have been identified through this effort. Also, the effort has underscored the need for additional blind prediction-based assessments.  相似文献   
27.
The usefulness of an arificial intelligence approach to some deterministic problems is discussed. An expert system approach to fracture mechanics problems is devised. Production rules for a simple expert system for crack tip mesh mapping are given. The knowledge acquisition process described in the references is used. Linear 2D fracture problems can be solved by the given program, though the methodology would be similar for non-linear or 3D problems.  相似文献   
28.
Hepatitis A virus infection is major cause of acute hepatitis in the United States, accounting for approximately 75,000 cases of clinical illness each year. These infections occur among persons in every age group and are associated with a variety of exposures related to fecal-oral transmission. Recently, the U.S. Food and Drug Administration approved licensure of two inactivated hepatitis A vaccines. Both vaccines are highly immunogenic and have been licensed in pediatric and adult formulations. The prevention of hepatitis A virus infection is directly related to many aspects of family practice, and family physicians may see patients in a variety of settings that warrant administration of hepatitis A vaccine. Groups for whom vaccination is currently recommended include international travelers, children in communities with high rates of hepatitis A virus infection, men who have sex with men, Illicit drug users, patients with chronic liver disease and persons with clotting factor disorders.  相似文献   
29.
Pulsed Nd:YAG lasers have been developed to achieve high peak power and high pulse repetition rate. These systems are being used as drivers for laser-produced plasmas which efficiently convert the 1064-nm laser output to extreme ultraviolet (EUV) light at 13.5 nm for future microlithography systems. The requirements for laser-produced plasma EUV light sources and their integration in lithography tools for high-volume manufacturing are reviewed to establish the key design issues for high-power lasers and plasma targets. Xenon has been identified as a leading target material to realize the goals of intense EUV emission and clean operation. Recent progress in high-power diode-pumped Nd:YAG lasers and xenon targets for EUV generation is reviewed, showing that laser-produced plasma sources meet the needs for current EUV lithography development tools. Future directions to meet EUV source requirements for high-volume manufacturing tools are discussed.  相似文献   
30.
Although self-administered questionnaires are major sources of information in epidemiology, comparatively little has been done to study practical aspects of design and mailing. The objective of this study was to evaluate various measures taken to increase the response rate. A questionnaire was mailed in July 1995 to a random sample (n = 2,000) of the Swedish population aged 20-79 years. Using a randomized factorial study design, the questionnaire and mailing procedures were changed in three ways: preliminary notification, length of the questionnaire, and mention of telephone contact. The overall questionnaire retrieval rate was 49%. Preliminary notification (adjusted odds ratio of receiving a completed questionnaire = 1.30, 95% confidence interval (CI) 1.08-1.56 relative to the absence of preliminary notification) and short length of the questionnaire (odds ratio = 1.24, 95% CI 1.04-1.48 relative to a long questionnaire) were both independently associated with a higher retrieval rate. Of eight possible combinations, the one comprising preliminary notification, a short questionnaire, and no mention of telephone contact gave the highest retrieval rate, 56%. The lowest retrieval rate, 40%, was observed for the combination of no preliminary notification, a long questionnaire, and mention of telephone contact. Young age, male sex, and urban residence significantly lowered the retrieval rate. Although there was a positive association between the questionnaire retrieval rate and partial nonresponse (missing answers in retrieved questionnaires), the marginal losses due to the latter did not cancel the gains by optimized mailing routines. Old age was the strongest determinant of partial nonresponse. The data provide evidence that design and mailing strategies, as well as demographic characteristics, may greatly influence the response rate of mailed epidemiologic questionnaires.  相似文献   
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