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51.
In this article, the performance objectives (POs) for Bacillus cereus group (BC) in celery, cheese, and spelt added as ingredients in a ready‐to‐eat mixed spelt salad, packaged under modified atmosphere, were calculated using a Bayesian approach. In order to derive the POs, BC detection and enumeration were performed in nine lots of naturally contaminated ingredients and final product. Moreover, the impact of specific production steps on the BC contamination was quantified. Finally, a sampling plan to verify the ingredient lots' compliance with each PO value at a 95% confidence level (CL) was defined. To calculate the POs, detection results as well as results above the limit of detection but below the limit of quantification (i.e., censored data) were analyzed. The most probable distribution of the censored data was determined and two‐dimensional (2D) Monte Carlo simulations were performed. The PO values were calculated to meet a food safety objective of 4 log10 cfu of BC for g of spelt salad at the time of consumption. When BC grows during storage between 0.90 and 1.90 log10 cfu/g, the POs for BC in celery, cheese, and spelt ranged between 1.21 log10 cfu/g for celery and 2.45 log10 cfu/g for spelt. This article represents the first attempt to manage the concept of PO and 2D Monte Carlo simulation in the flow chart of a complex food matrix, including raw and cooked ingredients.  相似文献   
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European Journal of Population - In the last decades, conventional patterns of assortative mating have been challenged by changes in the gender-gap in education. In many countries, educationally...  相似文献   
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Abstract

European and Italian libraries are strongly involved in efforts to facilitate access to European information resources. The Italian union catalogue of serials has evolved from a traditional catalog to a sophisticated resource that provides access to serials services. Serials control is the most recent service of the union catalog with features for end users and professional staff. The software is BASIS Techlib by ID Technology (Italy), affinity partner of Open Text (USA). The ability to customize features presents a very satisfactory, easy-to-use product that might be considered interesting for union catalogs in other countries. Serials Review 2003; 29:169–178.  相似文献   
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Students’ performance is a crucial aspect for university programs effectiveness and organization. In this paper, we introduce and analyze a performance index for the first-year students of a private Italian university, namely the Libera Università Maria Ss. Assunta. We use administrative data on 532 undergraduate students enrolled in any of the eight available bachelor degrees in 2015. Our aim is to improve the general understanding of performance linking it with personal student’s characteristics and with degree-specific aspects. A beta inflated latent class approach is employed to identify clusters of performance establishing a link with all available explanatory variables. The empirical analysis unveils that a good and balanced degree organization may improve students’ performance. The student’s ability plays a crucial role in discriminating between good and bad performances, and also strongly depends on individual-specific characteristics, such as the final mark obtained at high school.

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In recent years, the term social entrepreneur has become increasingly common in academic and business circles. Social entrepreneurs engage in a variety of activities, but always with the intention of solving social problems. Social entrepreneurs are not merely people who perform acts of charity; they have an evident desire to improve social well‐being and develop projects with long‐term vision. The creation of sustainable social value is a key characteristic that differentiates them from well‐meaning individuals who simply engage in charitable works. There are, however, significant gaps in our understanding of social entrepreneurs and few empirical studies on the subject. This present study attempts to identify the characteristics of more socially oriented entrepreneurs, using sociodemographic variables and the theory of universal values toward work. Analysis of a sample of approximately 400 people shows that more than half of entrepreneurial orientation can be explained through the possession of the values of self‐enhancement (with an inverse relationship in this case), self‐transcendence, and conservation. The theory of universal values has proved extraordinarily useful for studying the characteristics of social entrepreneurs.  相似文献   
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A closer look at the rich world of California feminisms demonstrates how Judy Grahn served as a central figure in bay area feminism, working to establish and support lesbian activist organizations, feminist publications, women's cultural events, and more. Two of Grahn's early political writings consider how lesbians sat at the nexus of homophobia and sexism. These writings demonstrate the formative role played by San Francisco lesbians in reframing ideas about “women-loving women” and the intersections of gender and sexuality in creating the oppressions faced by all women.  相似文献   
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Effective implementation of likelihood inference in models for high‐dimensional data often requires a simplified treatment of nuisance parameters, with these having to be replaced by handy estimates. In addition, the likelihood function may have been simplified by means of a partial specification of the model, as is the case when composite likelihood is used. In such circumstances tests and confidence regions for the parameter of interest may be constructed using Wald type and score type statistics, defined so as to account for nuisance parameter estimation or partial specification of the likelihood. In this paper a general analytical expression for the required asymptotic covariance matrices is derived, and suggestions for obtaining Monte Carlo approximations are presented. The same matrices are involved in a rescaling adjustment of the log likelihood ratio type statistic that we propose. This adjustment restores the usual chi‐squared asymptotic distribution, which is generally invalid after the simplifications considered. The practical implication is that, for a wide variety of likelihoods and nuisance parameter estimates, confidence regions for the parameters of interest are readily computable from the rescaled log likelihood ratio type statistic as well as from the Wald type and score type statistics. Two examples, a measurement error model with full likelihood and a spatial correlation model with pairwise likelihood, illustrate and compare the procedures. Wald type and score type statistics may give rise to confidence regions with unsatisfactory shape in small and moderate samples. In addition to having satisfactory shape, regions based on the rescaled log likelihood ratio type statistic show empirical coverage in reasonable agreement with nominal confidence levels.  相似文献   
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The deposition of amyloid beta protein (Abeta) in the human brain and the generation of neurofibrillary tangles are the histopathological hallmarks of Alzheimer's disease. Accumulation of Abeta takes place in senile plaques and in cerebrovascular deposits as a result of an imbalance between Abeta production and clearance. This Review describes the different types of Abeta deposits, which can be distinguished by their morphology and by the hierarchical involvement of distinct areas of the brain in Abeta deposition. The role of intracellular Abeta in Abeta deposition and the mechanism of Abeta toxicity are also discussed.  相似文献   
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