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Eric Angelini Gerard Camerini Malick Diop Patrice Roche Thomas Rodi Christine Schippa Thierry Thomas 《PloS one》2016,11(2)
Although the flavor and fragrance industry is about 150 years old, the use of synthetic materials started more than 100 years ago, and the awareness of the respiratory hazard presented by some flavoring substances emerged only recently. In 2001, the US National Institute of Occupational Safety and Health (NIOSH) identified for the first time inhalation exposure to flavoring substances in the workplace as a possible occupational hazard. As a consequence, manufacturers must comply with a variety of workplace safety requirements, and management has to ensure the improvement of health and safety of the employees exposed to hazardous volatile organic compounds. In this sensitive context, MANE opened its facilities to an intensive measuring campaign with the objective to better estimate the real level of hazardous respiratory exposure of workers. In this study, exposure to 27 hazardous volatile substances were measured during several types of handling operations (weighing-mixing, packaging, reconditioning-transferring), 430 measurement results were generated, and were exploited to propose an improved model derived from the well-known ECETOC-TRA model. The quantification of volatile substances in the working atmosphere involved three main steps: adsorption of the chemicals on a solid support, thermal desorption, followed by analysis by gas chromatography-mass spectrometry. Our approach was to examine experimental measures done in various manufacturing workplaces and to define correction factors to reflect more accurately working conditions and habits. Four correction factors were adjusted in the ECETOC-TRA to integrate important exposure variation factors: exposure duration, percentage of the substance in the composition, presence of collective protective equipment and wearing of personal protective equipment. Verification of the validity of the model is based on the comparison of the values obtained after adaptation of the ECETOC-TRA model, according to various exposure scenarios, with the experimental values measured under real conditions. After examination of the predicted results, 98% of the values obtained with the proposed new model were above the experimental values measured in real conditions. This must be compared with the results of the classical ECETOC-TRA system, which generates only 37% of overestimated values. As the values generated by the new model intended to help decision-makers of the industry to implement adapted protective action and information, and considering the high variability of the working environments, it was of the utmost importance to us not to underestimate the exposure level. The proposed correction factors have been designed to achieve this goal. We wish to propose the present method as an improved monitoring tool to improve respiratory health and safety in the flavor and fragrance manufacturing facilities. 相似文献
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Jorge Angelini Tania Taurian Carolina Morgante Fernando Ibá?ez Stella Castro Adriana Fabra 《Plant Physiology and Biochemistry》2005,43(8):754-759
In this work, the peanut nodulation kinetics by acid-sensitive and tolerant isolates under acid stress condition was analyzed. The results demonstrated that the acid pH produced a decrease in the number of nodules formed only when peanut plants were inoculated with acid-sensitive isolates but increased steadily by the addition of 10 mM Ca2+, reaching higher values than those obtained at pH 7.0. On the contrary, the peanut nodulation by acid-tolerant isolates was not affected by this stressing condition. These data suggest that acid-tolerant isolates could be used as a potential source of strains for preparing highly effective inoculants for peanut plants growing in acid soils. 相似文献
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The subcellular distribution of acid (pH 4.0) and neutral (pH 6.5) α-glucosidases was investigated in biopsy specimens of human skeletal muscle obtained from six normal subjects, four adult cases of acid maltase deficiency, and a case of myophosphorylase deficiency. The highest relative specific activity of acid glucosidase, as well as of other acid hydrolases, was observed in the light mitochondrial fraction. Relatively high acid phosphatase activity was also found in the microsomal fraction. In all muscles the highest relative specific activity of neutral glucosidase was in the microsomal fraction. In acid glucosidase deficient muscle no neutral glucosidase could be detected in the light and heavy mitochondrial fractions but in normal and myophosphorylase deficient muscle neutral glucosidase activity was also detectable in these fractions. The final supernatant of all muscles contained neutral glucoamylase activity. The relevance of these data to the pathogenesis of the different forms of type II glycogenosis is considered. 相似文献
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Summary The adenohypophysis of the newt Triturus cristatus carnifex Laur. shows three types of cells: 1) cells with granules of about 350–550 m in diameter, 2) cells with small granules of 200–250 m in diameter and globules with a cristal-like arrangement containing cylinders with a diameter of about 960 Å and 3) cells containing small granules only.The AA. discuss the ultrastructural changes of the gland and the modifications of sexual secondary characters (S.S.C.) in animals given Cyproterone acetate (1/2 mg every three days). The animals have been treated for a period of time varying between 3 and 5 months, starting in October-November, when S.S.C. begin to develop again.At the end of the treatment the newths showed a loss of S.S.C., and the ultrastructure of the adenohypophysis resembled that of castrated animals, i.e.: great swelling of R.E.R. and partial degranulation of glycoprotein secreting cells which contain the 200 m granules and the globules. The S.E.R. showed also swelling and hyperactivity.A preliminary communication of this paper has been presented at the Sixth conference of European Comparative Endocrinologists (Montpellier, August 8, 1971).This work has been supported by the Italian National Research Council (grant n° 115–1121). The E. M. observations have been performed in the Centro di Studio di Microscopia Elettronica of the Faculty of Sciences, University of Naples, directed by Prof. G. Ghiara.We thank Schering AG, Berlin, and in particular Drs. Brunnemann and Merz, for the generous donation of Cyproterone-acetate. 相似文献
57.
Bezerra Luis Artur Valões Angelini Ronaldo Vitule Jean Ricardo Simões Coll Marta Sánchez-Botero Jorge Iván 《Hydrobiologia》2018,817(1):475-489
Hydrobiologia - Fish and invertebrates are introduced in freshwaters around the world for commercial purposes, despite widely known impacts on food webs and biological invasions. As a proxy for... 相似文献
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Maria Laurenzi Giuseppina Rea Rodolfo Federico Paraskevi Tavladoraki Riccardo Angelini 《Planta》1999,208(2):146-154
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Marco Cervellini Michele Di Musciano Piero Zannini Simone Fattorini Borja JimnezAlfaro Emiliano Agrillo Fabio Attorre Pierangela Angelini Carl Beierkuhnlein Laura Casella Richard Field JanChristopher Fischer Piero Genovesi Samuel Hoffmann Severin D. H. Irl Juri Nascimbene Duccio Rocchini Manuel Steinbauer Ole R. Vetaas Alessandro Chiarucci 《Ecology and evolution》2021,11(24):18111
Habitat richness, that is, the diversity of ecosystem types, is a complex, spatially explicit aspect of biodiversity, which is affected by bioclimatic, geographic, and anthropogenic variables. The distribution of habitat types is a key component for understanding broad‐scale biodiversity and for developing conservation strategies. We used data on the distribution of European Union (EU) habitats to answer the following questions: (i) how do bioclimatic, geographic, and anthropogenic variables affect habitat richness? (ii) Which of those factors is the most important? (iii) How do interactions among these variables influence habitat richness and which combinations produce the strongest interactions? The distribution maps of 222 terrestrial habitat types as defined by the Natura 2000 network were used to calculate habitat richness for the 10 km × 10 km EU grid map. We then investigated how environmental variables affect habitat richness, using generalized linear models, generalized additive models, and boosted regression trees. The main factors associated with habitat richness were geographic variables, with negative relationships observed for both latitude and longitude, and a positive relationship for terrain ruggedness. Bioclimatic variables played a secondary role, with habitat richness increasing slightly with annual mean temperature and overall annual precipitation. We also found an interaction between anthropogenic variables, with the combination of increased landscape fragmentation and increased population density strongly decreasing habitat richness. This is the first attempt to disentangle spatial patterns of habitat richness at the continental scale, as a key tool for protecting biodiversity. The number of European habitats is related to geography more than climate and human pressure, reflecting a major component of biogeographical patterns similar to the drivers observed at the species level. The interaction between anthropogenic variables highlights the need for coordinated, continental‐scale management plans for biodiversity conservation. 相似文献
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