275 research outputs found

    Emission of Microbial Aerosols from Polluted Waters in Densely Populated Regions

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    The air surrounding three activated sludge tanks was sampled over a two year period for the emission of bacterial aerosols under a variety of climatic conditions and at varying distances upwind and downwind of the aerated tanks. All plants emitted species of enteric bacteria which are significant as index organisms and as frank pathogens. The emission pattern of these bacteria were influenced by distance from the plant and wind direction. Within the parameters of a plant, defined arbitrarily in this study by sampling sites less than 150 m upwind and less than 900 m downwind, distance from the source was the only reliable predictor of emissions, and no statistical significance was found in the differences between upwind and downwind samples at the same distances from the plant. Multiple regression analysis revealed no consistent influences of any environmental factor on emission rate, but relative humidity, wind speed, air temperature, and ozone levels showed some contribution on the bacterial count, while light intensity appeared to have little influence. The deposition and retention of enteric bacteria on foliage plants near aerated basins was used as an alternate sampling method, and it emphasized the potential hazard of these aerosols. This method confirmed the inability to predict the emission rate by climatic factors, but wind speed contributed directly to the counts, and there was a pronounced difference in the average counts of upwind and downwind samples. The LD50 in mice was the same for aerosolized Klebsiella pneumoniae as for a strain of Klebsiella pneumoniae recovered from the sputum of a patient with pneumonia. Escherichia, Enterobacter and Klebsiella were recovered from the respiratory tract of mice forced to inhale air at a sewage treatment plant when the respiratory organs were assayed immediately after exposure, but not when the assay followed a prolonged period of observation, during which there was also an absence of clinical symptoms. This investigation also included a pilot study of the numbers of viable cells in the colony forming units on plates exposed in an Andersen Sampler, and CFU was found to be an unreliable index of viable cell counts. The study concludes that bacterial aerosols are a hazard for residents living near package plants, and recommends adopting alternate methods of sewage treatment that would remove the emissions of numerous package plants from the environment of densely populated regions

    ENVIRONMENTAL AND HEALTH STUDIES OF KENTUCKY BLACKBIRD ROOSTS

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    At the present time we are under contract from the Kentucky Environmental Quality Commission to study three aspects of Kentucky starling-blackbird roost problems: (1) a study of birds killed this coming winter through PA-14 treatments, to obtain more accurate data on species composition, sex ratios, kill success and food items; (2) a compilation of breeding and wintering data on Kentucky populations through analysis of U.S. Fish and Wildlife Service summer bird counts and banding returns; and (3) a study of spore dispersal of various fungal species, most notably Histoplasma capsulatum, from roost sites. The winter sampling is yet to be done, as sprayings most likely will not be undertaken until December. The analysis of population figures is complete and will be partially reported herein, as some data may be of significance for application to future management efforts. The histoplasmosis study began in June 1976 and will continue throughout the winter and spring; some preliminary results are deemed of significance to management efforts and are also reported herein

    Late Eocene 3He and Ir anomalies associated with ordinary chondritic spinels

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    Abstract During the late Eocene there was an enigmatic enhancement in the flux of extraterrestrial material to Earth. Evidence comes from sedimentary 3He records indicating an increased flux of interplanetary dust during ca. 2 Myr, as well as two very large impact structures, Popigai (100 km diameter) and Chesapeake Bay (40–85 km), that formed within 10–20 kyr at the peak of the 3He delivery. The Massignano section in Italy has one of the best sedimentary records of these events, including a well-defined 3He record, an Ir-rich ejecta bed related to the Popigai impact event, and two smaller Ir anomalies. Recently we showed that the Popigai ejecta is associated with a significant enrichment of chromite grains (>63 μm) with an H-chondritic elemental composition (17 grains in 100 kg of rock). Most likely these grains are unmelted fragments from the impactor. Slightly higher up (ca. 20 cm) in the section, where a small Ir anomaly possibly related to the Chesapeake Bay impact has been measured, we found a weak enrichment in L-chondritic grains (8 grains in 208 kg of rock). Here we report an extended data set increasing the total amount of sediment dissolved in acid and searched for extraterrestrial chromite grains from 658 to 1168 kg. In altogether 760 kg of background sediment from 17 levels over 14 m of strata outside the interval corresponding to the Popigai and Chesapeake Bay impacts, we only found 2 extraterrestrial chromite grains. Both grains have L-chondritic compositions and were found in a 100 kg sample from the ca. 10.25 m level in the section where the second of the smaller Ir anomalies has been reported. A correlation appears to exist between Ir, 3He and chromite from ordinary chondrites. We also report oxygen three-isotope measurements of the extraterrestrial chromite grains associated with the Popigai ejecta and confirm an H-chondritic composition. The new results strengthen our scenario that the upper Eocene 3He and Ir enrichments originate from the asteroid belt rather than the Oort cloud as originally proposed when the 3He anomaly was discovered. The generally low background concentrations of extraterrestrial chromite through the section speak against any major single asteroid breakup event such as in the mid-Ordovician after the break-up of the L-chondrite parent body. Instead the data reconcile with a small, possibly a factor of 2–3, increase in the flux of extraterrestrial material to Earth, but of both H- and L-chondritic composition. We also report the composition of all the 2310 terrestrial chrome spinel grains recovered, and show that their chemical composition indicates a dominantly regional ophiolitic source. Four anomalous chrome spinel grains with high Ti and V concentrations were found in the Popigai ejecta. These grains originate from Siberian Traps basalts in the Popigai crater at the time of impact

    Enteric Virus Survival in Package Plants and the Upgrading of the Small Treatment Plants Using Ozone

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    Post-chlorinated effluent collected with a portable viral concentrator from four treatment plants in Jefferson County, Kentucky, yielded infective viral particles from three plants from spring through late fall. The pH, ,chlorine, turbidity, and coliform levels of these effluents indicated that viral persistence was correlated with inefficient processing which produced effluent environments that inhibited disinfection by chlorine. The disinfection potential of ozone was tested on secondary effluent and finished water seeded with poliovirus and Esaheriahia coli. Low doses of ozone inactivated viruses and bacteria in treated water, but not in effluent. The inactivation of bacteria by ozone does not appear to be caused by cell lysis. Inability of poliovirus to form plaques correlated with inhibition of capsid penetration. Electron micrographs revealed that ozone degrades capsids. Ozonation produced low levels of COD and TOC reduction in package plant effluent. Since the reaction rates were not a simple function of COD levels and ozone dose it would be difficult to standardize dose rates. The relative inefficiency of ozone in reduction of biological and non-biological pollutants in effluents, combined with its high cost, does not favor a recommendation for ozonation as a tack-on process to upgrade these plants

    How Do Bone Marrow Lesions Cause Osteoarthritis Pain? a Structural and Functional Tissue-Based Study

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    Background/Purpose: Susceptibility to ankylosing spondylitis (AS) is primarily genetic; thus far 113 susceptibility variants for AS have been identified. However, most of the AS associated SNPs do not directly affect protein-coding genes. Studies of disease- and trait-associated SNPs suggest they may act by affecting gene regulatory regions in specific cell types or tissues. Therefore, identifying the AS relevant cell types is crucial for further mechanistic studies. Methods: We applied several bioinformatics methods to utilize epigenetic, gene and protein expression information to identify the primary relevant cell types through which genetic variants associated with AS operate. In total, there are 113 AS associated loci; 39 of them show genome-wide significance in AS-only analyses, whereas the remainder are genome-wide significant in analyses leveraging pleiotrophy with other related diseases (Crohn’s disease (CD), psoriasis, primary sclerosing cholangitis (PSC) and ulcerative colitis (UC))1. Results: AS-associated SNPs are disproportionately found in regions bearing epigenetic marks indicating transcriptional activity found in immune cell types including monocytes, CD4+ and CD8+ T cells, NK cells, regulatory T cells, and B cells. Gene expression studies showed enrichment of AS associated loci in genes specifically expressed in monocytes and NK cells while protein expression study shows protein products of AS associated loci were significantly enriched in CD8+ T cells. Epigenetic analyses also showed evidence that AS-associated signals operate in gut cell types including in mucosa from the small intestine, sigmoid colon and rectum. These findings particularly relate to pleiotropic loci also associated with IBD, psoriasis, and PSC. Conclusion: These findings highlight the role of key immune cell types in the mechanism by which genetic associations with AS drive the disease, as well as providing further evidence for the involvement of the gut in the pathogenesis of AS. 1Ellinghaus D. at al, Nature Genetics 201

    Rare meteorites common in the Ordovician period

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    © 2017 Macmillan Publishers Limited, part of Springer Nature. All rights reserved. Most meteorites that fall today are H and L type ordinary chondrites, yet the main belt asteroids best positioned to deliver meteorites are LL chondrites 1,2. This suggests that the current meteorite flux is dominated by fragments from recent asteroid breakup events 3,4 and therefore is not representative over longer (100-Myr) timescales. Here we present the first reconstruction of the composition of the background meteorite flux to Earth on such timescales. From limestone that formed about one million years before the breakup of the L-chondrite parent body 466 Myr ago, we have recovered relict minerals from coarse micrometeorites. By elemental and oxygen-isotopic analyses, we show that before 466 Myr ago, achondrites from different asteroidal sources had similar or higher abundances than ordinary chondrites. The primitive achondrites, such as lodranites and acapulcoites, together with related ungrouped achondrites, made up ∼15-34% of the flux compared with only ∼0.45% today. Another group of abundant achondrites may be linked to a 500-km cratering event on (4) Vesta that filled the inner main belt with basaltic fragments a billion years ago 5. Our data show that the meteorite flux has varied over geological time as asteroid disruptions create new fragment populations that then slowly fade away from collisional and dynamical evolution. The current flux favours disruption events that are larger, younger and/or highly efficient at delivering material to Earth

    Сенсибилизация к аллергенам клещей домашней пыли у детей

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    ДЫХАТЕЛЬНАЯ ГИПЕРЧУВСТВИТЕЛЬНОСТЬАЛЛЕРГОЗЫ РЕСПИРАТОРНЫЕГИПЕРСЕНСИБИЛИЗАЦИЯ РЕСПИРАТОРНАЯРЕСПИРАТОРНАЯ АЛЛЕРГИЯАЛЛЕРГЕНЫКЛЕЩИ ПЫЛЕВЫЕ ДОМАШНИЕDERMATOPHAGOIDES PTERONYSSINUSDERMATOPHAGOIDES FARINAEСЕНСИБИЛИЗАЦИЯ БИОЛОГИЧЕСКАЯСЕНСИБИЛИЗАЦИЯ К АЛЛЕРГЕНАМДЕТИОБЗОР ЛИТЕРАТУРЫАллергические заболевания представляют серьезную проблему современной медицины. Сенсибилизация к ингаляционным аллергенам является одним из ключевых факторов формирования респираторных аллергозов. Среди аэроаллергенов важное значение играют аллергенные компоненты домашней пыли – клещи Dermatophagoides pteronyssinus и Dermatophagoides farinae, составляющие до 90% акарофауны жилых помещений. В формировании сенсибилизации к клещам домашней пыли также предполагается роль индивидуальных источников аллергенов. Сенсибилизация к мажорным компонентам аллергена клещей домашней пыли ассоциируется с риском развития бронхиальной астмы, к минорным (Der p 10) – риском развития перекрестных реакций с тропомиозином других беспозвоночных, тропомиозином человека. Аллергены клещей домашней пыли (Der p 2 и Der f 2) могут быть ответственны за симптомы оральной клещевой анафилаксии, а также способствовать развитию сенсибилизации к бактериальным антигенам Staphylococcus aureus и Escherichia coli. В 1 части статьи изложены биология и источники клеща домашней пыли. Представлена классификация аллергенов, пути сенсибилизации и распространенность сенсибилизации к клещу домашней пыли у детей.Allergic diseases are a serious problem in modern medicine. Sensitization to inhalation allergens is one of the key factors in the formation of respiratory allergoses. Among aeroallergens, allergenic components of domestic dust play an important role – mites Dermatophagoides pteronyssinus and Dermatophagoides farinae, that make up to 90% of the acarofauna of residential premises. In the formation of sensitization to domestic dust mites, the role of individual sources of allergens is also considered. Sensitization to the major components of the domestic dust mite allergens is associated with the risk of developing bronchial asthma, to minor ones (Der p 10) – the risk of cross-reactions with tropomyosin of other invertebrates, human tropomyosin. Domestic dust mite allergens (Der p 2 and Der f 2) may be responsible for the symptoms of oral tick-born anaphylaxis as well as for the development of sensitization to bacterial antigens of Staphylococcus aureus and Escherichia coli. Part 1 of this article outlines biology and sources of the domestic dust mite. The classification of allergens, sensitization pathways and the prevalence of sensitization to domestic dust mite in children are presented

    Patient perceptions of glucocorticoids in anti-neutrophil cytoplasmic antibody-associated vasculitis

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    © 2017, The Author(s). Granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA) are multisystem diseases of small blood vessels, collectively known as the anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV). This study explores the patient’s perspective on the use of glucocorticoids, which are still a mainstay of treatment in AAV. Patients with AAV from the UK, USA, and Canada were interviewed, using purposive sampling to include a range of disease manifestations and demographics. The project steering committee, including patient partners, designed the interview prompts and cues about AAV, its treatment, and impact on health-related quality of life. Interviews were transcribed and analysed to establish themes grounded in the data. A treatment-related code was used to focus analysis of salient themes related to glucocorticoid therapy. Fifty interviews were conducted. Individual themes related to therapy with glucocorticoids emerged from the data and were analysed. Three overarching themes emerged: (1) Glucocorticoids are effective at the time of diagnosis and during relapse, and withdrawal can potentiate a flare, (2) glucocorticoids are associated with salient emotional, physical, and social effects (depression, anxiety, irritation, weight gain and change in appearance, diabetes mellitus, effect on family and work); and (3) patient perceptions of balancing the risks and benefits of glucocorticoids. Patients identified the positive aspects of treatment with glucocorticoids; they are fast-acting and effective, but, they voiced concerns about adverse effects and the uncertainty of the dose-reduction process. These results may be informative in the development of novel glucocorticoid-sparing regimens
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