820,667 research outputs found

    Strategies for estimating human exposure to mycotoxins via food

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    In this review, five strategies to estimate mycotoxin exposure of a (sub-) population via food, including data collection, are discussed with the aim to identify the added values and limitations of each strategy for risk assessment of these chemicals. The well-established point estimate, observed individual mean, probabilistic and duplicate diet strategies are addressed, as well as the emerging human biomonitoring strategy. All five exposure assessment strategies allow the estimation of chronic (long-term) exposure to mycotoxins, and, with the exception of the observed individual mean strategy, also acute (short-term) exposure. Methods for data collection, i.e. food consumption surveys, food monitoring studies and total diet studies are discussed. In food monitoring studies, the driving force is often enforcement of legal limits, and, consequently, data are often generated with relatively high limits of quantification and targeted at products suspected to contain mycotoxin levels above these legal limits. Total diet studies provide a solid base for chronic exposure assessments since they provide mycotoxin levels in food based on well-defined samples and including the effect of food preparation. Duplicate diet studies and human biomonitoring studies reveal the actual exposure but often involve a restricted group of human volunteers and a limited time period. Human biomonitoring studies may also include exposure to mycotoxins from other sources than food, and exposure to modified mycotoxins that may not be detected with current analytical methods. Low limits of quantification are required for analytical methods applied for data collection to avoid large uncertainties in the exposure due to high numbers of left censored data, i.e. with levels below the limit of quantification

    The Solid-Phase Part of Supported Small-Molecule Synthesis

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    The synthesis of small molecules on solid phase must not only address the vagaries of C–C-bond formation and functional-group manipulation, but must also take into account solid-support issues such as 'point of attachment', 'resin compatibility', 'reagent accesibility', and 'product liberation'. Hence, the resin plays a vital role in the solid-phase venture and the polymer advantages can be summarized as reactions can be driven to completion by addition of excess solution-phase reagents, reaction products are 'isolated' by filtration and washing, and multiple-step synthesis terminating with a 'selective' liberation step can deliver essentially pure product. These issues, as well as a number of strategies for the preparation and functionalization of resin supports, are discussed

    Optimistic search strategy: Change point detection for large-scale data via adaptive logarithmic queries

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    As a classical and ever reviving topic, change point detection is often formulated as a search for the maximum of a gain function describing improved fits when segmenting the data. Searching through all candidate split points on the grid for finding the best one requires O(T)O(T) evaluations of the gain function for an interval with TT observations. If each evaluation is computationally demanding (e.g. in high-dimensional models), this can become infeasible. Instead, we propose optimistic search strategies with O(log⁥T)O(\log T) evaluations exploiting specific structure of the gain function. Towards solid understanding of our strategies, we investigate in detail the classical univariate Gaussian change in mean setup. For some of our proposals we prove asymptotic minimax optimality for single and multiple change point scenarios. Our search strategies generalize far beyond the theoretically analyzed univariate setup. We illustrate, as an example, massive computational speedup in change point detection for high-dimensional Gaussian graphical models. More generally, we demonstrate empirically that our optimistic search methods lead to competitive estimation performance while heavily reducing run-time.Comment: extended Table 1; added Model II and Lemma 5.3; added further minor explanation

    Effective ways of teaching children with Autism Spectrum Disorder in Inclusive Physical Education Setting

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    The purpose of this synthesis is to provide effective teaching strategies for inclusion of students with autism in adapted physical education settings. To that end, a literature review produced a critical mass of 16 relevant articles identifying strategies such as prompting, video modeling, variable intensity prompting (i.e., flexible and most-to-least), antecedent-based intervention, peer tutoring and self-management. These strategies are further discussed to provide practical ways physical educators can use to include students with autism to general or adapted physical education settings. Based on gathered data, there is strong evidence supporting the benefits of variable intensity prompting strategies like most-to-least. Evidence also supports that antecedent-based methodology provides a solid starting point to develop interventions that can incorporate other teaching strategies. As an educator, using proper and effective teaching methods provides the opportunity to improve the students’ quality of life

    Critical analysis of the integration of residual municipal solid waste incineration and selective collection in two Italian tourist areas

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    Municipal solid waste management is not only a contemporary problem, but also an issue at world level. In detail, the tourist areas are more difficult to be managed. The dynamics of municipal solid waste production in tourist areas is affected by the addition of a significant amount of population equivalent during a few months. Consequences are seen in terms of the amount of municipal solid waste to be managed, but also on the quality of selective collection. In this article two case studies are analyzed in order to point out some strategies useful for a correct management of this problem, also taking into account the interactions with the sector of waste-to-energy. The case studies concern a tourist area in the north of Italy and another area in the south. Peak production is clearly visible during the year. Selective collection variations demonstrate that the tourists' behavior is not adequate to get the same results as with the resident population. © The Author(s) 2014

    Platonic solids back in the sky: icosahedral inflation

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    We generalize the model of solid inflation to an anisotropic cosmic solid. Barring fine tunings, the observed isotropy of the cosmological background and of the scalar two-point function isolate the icosahedral group as the only possible symmetry group of such a solid. In such a case, higher-point correlation functions—starting with the three-point one—are naturally maximally anisotropic, which makes the standard detection strategies highly inefficient and calls for a dedicated analysis of CMB data. The tensor two-point function can also be highly anisotropic, but only in the presence of sizable higher-derivative couplings

    Europeana communication bug: which intervention strategy for a better cooperation with creative industry?

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    Although Europeana as well as many GLAMs are very engaged - beside the main mission, i.e. spreading cultural heritage knowledge- in developing new strategies in order to make digital contents reusable for creative industry, these efforts have been successful just only in sporadic cases. A significant know how deficits in communication often compromises expected outcomes and impact. Indeed, what prevails is an idea of communication like an enhancement “instrument” intended on the one hand in purely economic (development) sense, on the other hand as a way for increasing and spreading knowledge. The main reference model is more or less as follows: digital objects are to be captured and/or transformed by digital technologies into sellable goods to put into circulation. Nevertheless, this approach risks neglecting the real nature of communication, and more in detail the one of digital heritage where it is strategic not so much producing objects and goods as taking part into sharing environments creation (media) by engaged communities, small or large they may be. The environments act as meeting and interchange point, and consequently as driving force of enhancing. Only in a complex context of network interaction on line accessible digital heritage contents become a strategic resource for creating environments in which their re/mediation can occur – provided that credible strategies exist, shared by stakeholders and users. This paper particularly describes a case study including proposals for an effective connection among Europeana, GLAMs and Creative Industry in the framework of Food and Drink digital heritage enhancement and promotion. Experimental experiences as the one described in this paper anyway confirm the relevance of up-to-date policies based on an adequate communication concept, on solid partnerships with enterprise and association networks, on collaborative on line environments, on effective availability at least for most of contents by increasing free licensing, and finally on grassroots content implementation involving prosumers audience, even if filtered by GLAMs

    Biosorbents in the Metallic Ions Determination

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    This chapter provides an overview and discusses analytical strategies for metallic ions determination using solid phase extraction. Solid phase extraction (SPE) is a much-used technique for extraction and/or concentration of complex samples, so that the analytes present in low concentration were detected mainly using chromatographic methods. However, in recent years, this technique has been widely used in the development of methodologies for metallic ions determination in the deferential samples. This technique shows simplicity and rapidity comparing with other conventional techniques, liquid–liquid extraction, cloud point extraction and others. Solid phase extraction procedures become even more interesting when commercial adsorbents are exchanged for others with higher adsorptive capacity, selectivity, flexibility, economy and low environmental impacts. For this purpose, some inorganic, organic and several natural adsorbents are used. New approaches to obtain adsorbent materials from natural sources such as fungi, bacteria, industrial residues and composting materials have received attention. These materials have been used in the development of analytical methods with varied proposals, such as preconcentration or speciation of metal ions

    Determinanty zaangaĆŒowania i efektywnoƛci zawodowej

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    Psychological research on work engagement and effectiveness has been predominantly conducted in relation to people management styles, work environment characteristics, as well as psychological determinants of individual's work involvement. Due to the complexity of a model being a combination of all the above mentioned factors, the reality analyzed within organizational research is usually simplified. An effort to combine these three areas leads to conclusions which provide solid foundations for efficient motivational strategies. At the same time, the article outlines a strong necessity to research the topic of motivation management and employee involvement, which are due should be considered from holistic point of view
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