845 research outputs found

    Assessment of Indoor Air Quality Problems in Office-Like Environments : Role of Occupational Health Services

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    There is an increasing concern about indoor air quality (IAQ) and its impact on health, comfort, and work-performance in office-like environments and their workers, which account for most of the labor force. The Scientific Committee on Indoor Air Quality and Health of the ICOH (Int. Comm. Occup. Health) has discussed the assessment and management of IAQ problems and proposed a stepwise approach to be conducted by a multidisciplinary team. It is recommended to integrate the building assessment, inspection by walk-through of the office workplace, questionnaire survey, and environmental measurements, in that order. The survey should cover perceived IAQ, symptoms, and psychosocial working aspects. The outcome can be used for mapping the IAQ and to prioritize the order in which problems should be dealt with. Individual health surveillance in relation to IAQ is proposed only when periodical health surveillance is already performed for other risks (e.g., video display units) or when specific clinical examination of workers is required due to the occurrence of diseases that may be linked to IAQ (e.g., Legionnaire's disease), recurrent inflammation, infections of eyes, respiratory airway effects, and sensorial disturbances. Environmental and personal risk factors should also be compiled and assessed. Workplace health promotion should include programs for smoking cessation and stress and IAQ management

    Global analysis of the sugarcane microtranscriptome reveals a unique composition of small RNAs associated with axillary bud outgrowth

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    Axillary bud outgrowth determines shoot architecture and is under the control of endogenous hormones and a fine-tuned gene-expression network, which probably includes small RNAs (sRNAs). Although it is well known that sRNAs act broadly in plant development, our understanding about their roles in vegetative bud outgrowth remains limited. Moreover, the expression profiles of microRNAs (miRNAs) and their targets within axillary buds are largely unknown. Here, we employed sRNA next-generation sequencing as well as computational and gene-expression analysis to identify and quantify sRNAs and their targets in vegetative axillary buds of the biofuel crop sugarcane (Saccharum spp.). Computational analysis allowed the identification of 26 conserved miRNA families and two putative novel miRNAs, as well as a number of trans-acting small interfering RNAs. sRNAs associated with transposable elements and protein-encoding genes were similarly represented in both inactive and developing bud libraries. Conversely, sequencing and quantitative reverse transcription-PCR results revealed that specific miRNAs were differentially expressed in developing buds, and some correlated negatively with the expression of their targets at specific stages of axillary bud development. For instance, the expression patterns of miR159 and its target GAMYB suggested that they may play roles in regulating abscisic acid-signalling pathways during sugarcane bud outgrowth. Our work reveals, for the first time, differences in the composition and expression profiles of diverse sRNAs and targets between inactive and developing vegetative buds that, together with the endogenous balance of specific hormones, may be important in regulating axillary bud outgrowth

    Asymmetry determines the effects of natural ceramides on model membranes

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    Ceramides can dramatically influence the lateral organization of biological membranes. In particular, ceramide-induced alterations of protein-lipid domains can be involved in several cellular processes, ranging from senescence to immune response. In this context, an important role is played by the length of the fatty acid bound to the sphingosine moiety. Asymmetric, heterogeneous ceramides,with more than 20 or less than 16 carbon atoms in the fatty acyl chain, in fact exert diverging effects in vivo if compared to their symmetric counterparts. In this work, we investigated the role of ceramide asymmetry and heterogeneity in model membranes showing raft-like phase separation, using a combination of fluorescence imaging, atomic force microscopy, fluorescence correlation spectroscopy and differential scanning calorimetry. We show that ceramide produced enzymatically from natural mixtures of sphingomyelin can dramatically alter the mixing behaviour of proteins and lipids in the membrane, inducing a homogenization of the bilayer. Furthermore, we characterized the physical properties of coexisting lipid phases at equilibrium in membranes with varying ceramide content, emphasizing the differences between symmetric-homogeneous and asymmetric-heterogeneous ceramides. While symmetric ceramides always produce enhanced order, asymmetric ceramides display a more complex behavior similar to that of cholesterol. Our results might help contribute to a more precise understanding of the rearrangements induced by different kinds of ceramide generation in cellular membranes

    442-Pos B197

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    Hard probes in heavy ion collisions at the LHC: heavy flavour physics

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    We present the results from the heavy quarks and quarkonia working group. This report gives benchmark heavy quark and quarkonium cross sections for pppp and pApA collisions at the LHC against which the AAAA rates can be compared in the study of the quark-gluon plasma. We also provide an assessment of the theoretical uncertainties in these benchmarks. We then discuss some of the cold matter effects on quarkonia production, including nuclear absorption, scattering by produced hadrons, and energy loss in the medium. Hot matter effects that could reduce the observed quarkonium rates such as color screening and thermal activation are then discussed. Possible quarkonium enhancement through coalescence of uncorrelated heavy quarks and antiquarks is also described. Finally, we discuss the capabilities of the LHC detectors to measure heavy quarks and quarkonia as well as the Monte Carlo generators used in the data analysis.Comment: 126 pages Latex; 96 figures included. Subgroup report, to appear in the CERN Yellow Book of the workshop: Hard Probes in Heavy Ion Collisions at the LHC. See also http://a.home.cern.ch/f/frixione/www/hvq.html for a version with better quality for a few plot

    Caracterização preliminar do cacho e da qualidade da uva de onze clones putativos da cultivar "Moscato Branco".

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    O cacho da cultivar ?Moscato Branco? apresenta compacidade elevada, o que favorece a ocorrência de podridões. Onze clones putativos da cultivar ?Moscato Branco? foram coletados na Serra Gaúcha e estão sendo avaliados para confirmar diferenças em relação à cultivar original

    The EFA Project: Indoor air quality in European schools. In:

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    ABSTRACT The objectives of the EFA project 'Indoor Air Pollution in Schools' were to collect information on indoor air quality (IAQ) in European schools, to review the related policies and preventive programs and to formulate recommendations aimed at providing a healthy school environment. IAQ in schools should be recognized as a priority topic for public health. School buildings are used by a large number of people for a long time but its IAQ has been much less studied than in other buildings. Schools frequently have serious indoor problems because of poor building construction, maintenance, cleaning and ventilation; high levels of VOCs and allergens are reported. The IAQ in schools can cause various short-and long-term negative health effects and discomfort, particularly in subjects with allergy. Nowadays only a very few European countries have guidelines aimed at improving IAQ. A multidisciplinary European program aimed at improving the IAQ in schools is needed. INDEX TERMS Schools, air pollutants, allergies and asthma, policy. INTRODUCTION The European Federation of Asthma and Allergy Associations (EFA) is a patients' network representing 250,000 individuals who are members of 33 associations in 17 European countries. The aim of this Federation is to improve the health conditions and quality of life of people with asthma and allergy throughout Europe. In 1995 an EFA study clearly illustrated the need for investigations about the impact of environmental factors on the health conditions of people with asthma and allergy (EFA, 1997). It was in this light that EFA received a grant from the European Commission, DG SANCO, for the project 'Indoor Air Pollution in Schools'. This project focussed on indoor air quality (IAQ) and its health effects (primarily asthma and allergy) in nursery, primary, and secondary schools in Europe. The objectives of this project were: to collect information on IAQ in European schools; to review policies and preventive programs of European countries in this field; to formulate recommendations aimed at providing a healthy school environment

    Correlations of Heavy Quarks Produced at Large Hadron Collider

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    We study the correlations of heavy quarks produced in relativistic heavy ion collisions and find them to be quite sensitive to the effects of the medium and the production mechanisms. In order to put this on a quantitative footing, as a first step, we analyze the azimuthal, transverse momentum, and rapidity correlations of heavy quark-anti quark (QQ‾Q\overline{Q}) pairs in pppp collisions at O\cal{O}(αs3\alpha_{s}^{3}). This sets the stage for the identification and study of medium modification of similar correlations in relativistic collision of heavy nuclei at the Large Hadron Collider. Next we study the additional production of charm quarks in heavy ion collisions due to multiple scatterings, {\it viz.}, jet-jet collisions, jet-thermal collisions, and thermal interactions. We find that these give rise to azimuthal correlations which are quite different from those arising from prompt initial production at leading order and at next to leading order.Comment: 26 pages, 15 figures. Three new figures added, comparison to experimental data included, abstract and discussion expande

    I valori limite per agenti chimici alla luce del Regolamento REACH

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    The European Regulation 1907/2006 (REACH - Registration, Evaluation, Authorization and Restriction of Chemicals) obliges manufacture companies and import chemicals to assess the risks arising from their use and to take the necessary measures to manage the risks identified. The Chemical Safety Report provides an accurate assessment of hazards to human health and the environment necessary to prepare an exposure scenario for the \u201cidentified uses\u201d of the substance. An exposure scenario is the set of conditions that describe how the substance is manufactured or used during its life cycle and how the manufacturer or importer controls, or recommends downstream users to control the \u2018exposure to humans and the environment. Firms therefore need specific skills. The spectrum of toxicological risk is extremely large, the information required in some cases are very complex and undoubtedly require a thorough knowledge in toxicology and environmental industry. The expertise and experience in toxicology of the occupational physician in this case may become useful in the environmental field as well as another familiar figure of relevant importance is the occupational hygienist who develop exposure scenarios for workers and their uses experience for the exposure scenarios for the consumer. It provides an obvious involvement of medical toxicologists and occupational hygienists for public tasks of control and inspection of chemical safety reports and, locally, even the accuracy of risk that arise from this
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