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[en] Results achieved by bio technical experts in radiometric control of subjects under veterinary-sanitary and phytate-sanitary supervision during the past decade (from 1985 to 1995), are presented. These results refer to radioactive cesium in relevant samples of the food chain during pre accidental, accidental and post accidental periods. In connection with this, the significant role of bio technical experts was emphasized in radiation protection of the human population. 5 refs.; 4 tabs
[en] Ensuring food safety (FS) is a persistent concern frequently faced by many countries. Safeguarding the quality of food that is fit for human consumption is the primary responsibility of the governmental regulatory agencies. For most part, agro-industries and food processors assume voluntary leadership for producing safe food. However, in the event of FS breach, the regulatory responsibility kicks into identify and rectify the situation. Notwithstanding whether it is the regulator or the industry that institutes the remedial action (e.g. improved hygiene and refined agricultural and manufacturing practices), the role of laboratory measurements is central in safeguarding the integrity of a functioning FS system. There are many analytical tools available to implement this task, such as validated analytical methods, natural matrix reference materials, field tested monitoring systems (proactive assessment) and effective surveillance systems (constant vigilance to prevent repeat safety violations). Way forward: existing FS tools are insufficient and should be strengthened with innovative approaches. Examples are: assembling swift intervention logistics to face FS breaches; rapid response systems including communication; robust metrology based measurement systems located at strategic locations in the country; and inter-disciplinary human resource to match the need for capacity development. These issues are discussed. (author)
[en] A useful endpoint of accident consequence assessment codes is the distribution of doses among the population. To produce this information for doses arising from ingestion, data are needed on the distribution of food between the point of production and the point of consumption. This paper describes the results of a preliminary investigation of the broad patterns of food distribution in the UK for six basic categories of food. The food categories considered were fresh milk, beef, mutton/lamb, grain, root crops and green vegetables. In the course of the investigation a wide range of individuals and organisations involved in food production, distribution and marketing were approached. The extent and quality of the information received varied with the foodstuff. This information was then supplemented with data derived from agricultural and population grids which indicated the patterns of supply and demand for each food category. For the purposes of the study the UK was subdivided into 9 regions, and the percentage of food produced in each source region that is consumed in each target region was then estimated for each food category. Although the data obtained were not detailed, they were sufficient to enable scoping calculations of the likely significance of food distribution patterns to be performed. The results of these calculations are discussed
[en] The contribution of this research is to propose a new problem of linear-mixed programming model (LMPM) for the allocation-packing of multiple pantries personalized for Food Banks (FB) considering the opinion of the Decision Maker (DM) in the selection of the best solution. Design/methodology/approach: A food allocation-packing system is modeled as a mixed integer problem (MIP) and a fuzzy mixed integer linear problem (FMILP). 250 families and 100 products were considered. The solutions were found using Lingo 13® (for both deterministic and fuzzy model). To select a good solution in the fuzzy model, this research adapted an interactive method proposed in the literature. The relevance of this modification is that the opinion of a decision maker (DM) is included and considered. Findings: The results for the deterministic and fuzzy model are compared in terms of their accomplishment of the restrictions (mainly nutritional and logistic) and the time needed to achieve a solution. Research limitations/implications: This paper was done considering quantity, weight and volume restrictions so that the pantry will contain a variety of products; it is not considered how the products will be stored into the pantry. Practical implications: This research proposes an alternative food management system at a food bank. The proposed system organizes the content of customized food pantries by the bias of a food allocation model. Social implications: Our paper analyzes a Food Bank (FB) in México. With this proposal, food will be distributed to families in poverty considering their particular nutritional needs. Originality/value: The main contribution of this article lies in the proposal of a new model of mixed integer linear problem (MILP) for the allocation-packing of food, solved with fuzzy possibilistic programming that simultaneously considers nutritional and logistic restrictions applied to a type of organization that has been little studied in the literature and where the opinion of Decision Maker (DM) is very important in the operational decisions involved in the Food Supply Chain (FSC) of a Food Bank (FB).
[en] The studies carried out by the Geographical Institute of Aix-en-Provence and the B.E.G.E.A. are in three forms: the first studies the local rural production (farming, animal rearing and fishing); the second is concerned with the food intake of the population within a radius of 5 to 10 km around the site; the third consists in working out a soil utilization map covering an area of about 2500 hectares around the site in order to determine the agricultural and urban areas as well as the open spaces, and the exact sort of cultivation carried out, plot by plot. The map also represents all the phenomena concerning hydrography, irrigation, watering and the supply of potable water. All these studies concern only a few parishes and enable an accurate knowledge of the environment to be acquired. The food studies seek an order of magnitude of the amount of local produce consumed by the populations of the nuclear power station sites with a view to determining radioactive contamination levels. The results show the specific food consumption features of a population bearing the deep stamp of its environment and its rural origin
[fr]Les etudes realisees par l'Institut de Geographie d'Aix-en-Provence, puis par le B.E.G.E.A., se presentent sous trois formes: la premiere etudie la production rurale locale (agriculture, elevage, peche); la seconde, s'interesse a la ration alimentaire de la population dans un rayon de 5 a 10 kilometres autour du site; la troisieme, consiste a elaborer une carte d'utilisation du sol couvrant une superficie de 2500 ha environ autour d'un site de facon a determiner les zones agricoles urbaines, et les espaces naturels, ainsi que la nature exacte des cultures pratiquees, parcelle par parcelle. La carte represente egalement tous les phenomenes ayant trait a l'hydrographie, l'irrigation, l'arrosage et l'alimentation en eau potable. Toutes ces etudes ne concernent que quelques communes et permettent une connaissance precise du milieu. Les etudes alimentaires recherchent un ordre de grandeur chiffre de la consommation des produits d'origine locale par les populations des sites electro-nucleaires en vue de la determination des niveaux de contamination radioactive. Les resultats montrent des traits specifiques de la consommation d'une population fortement marquee par son milieu ou ses origines rurales
[en] The present report about an EC-Workshop 'The transfer of Radionuclides in Natural and Semi-Natural Environments', which took place in Udine (Passariano), 11th to 15th september 1989, deals with the manifold new results of radioecology, which were obtained after the reactor accident in Chernobyl. Especially those mechanisms, which lead to the increased radionuclide concentration in foodstuff from natural and seminatural ecosystems are elucidated and some possibilities to decrease the radionuclide transfer to man are discussed. (Authors)
[en] A flexible and interactive code, NEPTUN, has been written in FORTRAN IV for the PDP-10 computer to assess the impact on man of radionuclides in aquatic food chains. NEPTUN is based on an equilibrium model of the linear-chain type, and calculates aquatic food concentrations and doses to man. A decay term is included for the holdup time of the various food types. A total of seven food types can be selected, which include drinking water, freshwater and salt-water plants, inverebrates and fish. Thirty different diets can be implemented and five different dose factor files can be chosen. These include dose conversion factors for infants and adults based on ICRP 2 and ICRP 26 methodologies. All dose factors involve a dose commitment of 50 years, or equivalently, 50 years of chronic exposure. To date, only stochastic ICRP 26 dose caluclations have been implemented. The basic concentration factor file contains data for 211 different radionuclides; the dose factor files are less comprehensive. However, all files can be readily expanded. The output includes tables of concentrations and doses for individual radionuclides, as well as summaries for groups of radionuclides. Existing aquatic food chain models and the sources of currently-used generic concentration factors are briefly reviewed, and dose factors based on ICRP 2 and ICRP 26 methodologies are contrasted. (auth)
[en] Radioecology - according to W. Whicker - can be understood as being the science, which attempts to comprehend and predict the transport of radionuclides through natural and agricultural ecosystems to a number of receptors such as plants, animals and man, which studies the impacts of environmental radioactivity on plants and animals, especially at the population and community levels, and, ultimately, which uses radioisotopes as tracers in order to understand ecological processes. During the approximately 90 years of radioecology research much progress has been made in this field which has been stimulated by the perception of environmental radioactivity at the beginning of this century, by atomic bomb tests carried out above ground, by the detection of areas with greatly enhanced natural radioactivity, the development of tracer techniques, and by a number of problems emerging in nuclear engineering (licensing procedures, accidents, etc.). In this survey paper the progress mentioned above will be illustrated by some examples; some recent results of relevant activities will be discussed, and the present limits of understanding of important processes and of modeling of the most important transport mechanisms will be indicated. It seems that significant further progress will heavily depend on the status of knowledge accumulated in a broad field of general environmental sciences. (orig.)
[de]Radiooekologie kann - nach W. Whicker - verstanden werden als die Wissenschaft, die den Transport von Radionukliden durch natuerliche und landwirtschaftliche Oekosysteme hin zu verschiedenen Rezeptoren wie Pflanzen, Tiere und den Menschen zu verstehen und vorherzusagen versucht, die Wirkungen von Umweltradioaktivitaet auf Pflanzen und Tiere, insbesondere auf der Populations- und Gemeinschaftsebene studiert, und schliesslich Radioisotope als Tracer einsetzt, um oekologische Prozesse zu verstehen. In den etwa 90 Jahren Radiooekologie hat es grosse Fortschritte auf diesem Gebiet gegeben, die durch die Wahrnehmung der Umweltradioaktivitaet zu Beginn dieses Jahrhunderts, die oberirdischen Atombombentests, die Entdeckung von Gebieten stark erhoehter natuerlicher Radioaktivitaet, die Entwicklung von Tracertechniken und durch verschiedene kerntechnische Fragestellungen (Genehmigungsverfahren, Unfaelle, etc.) stimuliert wurden. In diesem Uebersichtsbericht soll auf diese Fortschritte anhand einiger Beispiele eingegangen werden, einige neuere Ergebnisse derartiger Forschungen diskutiert und die gegenwaertigen Grenzen des Verstaendnisses wichtiger Prozesse und der Modellierung der wichtigsten Transportmechanismen aufgezeigt werden. Es scheint, dass signifikante weitere Fortschritte stark vom jeweiligen Erkenntnisstand auf einem breiten Bereich von allgemeinen Umweltwissenschaften abhaengen. (orig.)
[en] Resource partitioning is a central issue in ecology because it can establish to which point similar species can coexist in the same habitat. Great tits and blue tits have been classical model species in studies of trophic competence. However, most studies on the topic have been conducted at localities where caterpillars are by far the most relevant prey brought to the nestlings. In Mediterranean mixed forests, nevertheless, the abundance of caterpillars is relatively low and it is spiders that play a key role in the diet of great tits, at least for nestlings. The aim of this paper was to study nest food provisioning to establish the degree of diet overlap of these two tit species in a Mediterranean forest. Our results showed that blue tit feeding rates were higher than those of great tits, probably to compensate for the smaller prey delivered to nestlings by blue tits. Blue tits brought more spiders than great tits, while grey tits brought larger prey and more caterpillars. This may be because larger great tits can prey upon larger prey items than blue tits. As a main result, this study supports the view of resource partitioning by great and blue tits in sclerophyllous Mediterranean forest ecosystem. (Author)
[en] A three-species food chain model is proposed with dynamically variable adaptive traits in the intermediate consumer. We prove that its solutions are non-negative and bounded, and we analyze the existence and stability of its equilibria. By applying Li and Muldowney's [Li MY, Muldowney J. On Bendixson's criterion. J Differ Equ 1993;106:27-39] high-dimensional Bendixson criterion, we show that the positive equilibrium is globally stable under specific conditions. We support our analytical findings with numerical simulations.