28 research outputs found

    Hydrological thresholds and basin control over paleoflood records in lakes

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    The scarcity of long-term hydrological data is a barrier to reliably determining the likelihood of floods becoming more frequent and/or intense in a warmer world. Lake sediments preserve characteristic event layers, offering the potential to develop widely distributed and unique chronologies of historical floods. Inferring flood magnitude remains a greater challenge, previously overcome in part by analyzing sharply laminated polar or alpine sequences. Here we demonstrate an approach to obtain flood frequency and magnitude data from an unexploited resource, the largely visually homogeneous, organic sediments that typify most temperate lakes. The geochemical composition and end-member modeling of sediment trap and adjacent short core particle size data for Brotherswater (northwest England) discriminates the signature of infrequent, coarse-grained flood deposits from seasonal and longer-term allogenic (enhanced discharge and sediment supply during winter) and autogenic (summer productivity, thermal mixing) depositional processes. Comparing the paleoflood reconstruction to local river discharges shows that hydrological thresholds censor event signature preservation, with 4 yr recurrence intervals detectable in delta-proximal sediments declining to 9 yr in the lake center. Event threshold (discharge) and process characterization are essential precursors to discerning flood magnitude from sediment archives. Implementation of our approach in globally prevalent temperate lakes offers a vast, unique repository of long-term hydrological data for hydrologists, climate modelers, engineers, and policy makers addressing future flood risks

    Upwelling on the continental slope of the Alaskan Beaufort Sea : storms, ice, and oceanographic response

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    Author Posting. © American Geophysical Union, 2009. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 114 (2009): C00A13, doi:10.1029/2008JC005009.The characteristics of Pacific-born storms that cause upwelling along the Beaufort Sea continental slope, the oceanographic response, and the modulation of the response due to sea ice are investigated. In fall 2002 a mooring array located near 152°W measured 11 significant upwelling events that brought warm and salty Atlantic water to shallow depths. When comparing the storms that caused these events to other Aleutian lows that did not induce upwelling, interesting trends emerged. Upwelling occurred most frequently when storms were located in a region near the eastern end of the Aleutian Island Arc and Alaskan Peninsula. Not only were these storms deep but they generally had northward-tending trajectories. While the steering flow aloft aided this northward progression, the occurrence of lee cyclogenesis due to the orography of Alaska seems to play a role as well in expanding the meridional influence of the storms. In late fall and early winter both the intensity and frequency of the upwelling diminished significantly at the array site. It is argued that the reduction in amplitude was due to the onset of heavy pack ice, while the decreased frequency was due to two different upper-level atmospheric blocking patterns inhibiting the far field influence of the storms.The following grants provided support for this study: National Science Foundation grants OPP-0731928 (R.S.P.) and OPP-0713250 (R.S.P. and P.S.F.), Office of Naval Research grant N00014-07-1-1040 (D.J.T. and R.A.G.), Natural Sciences and Engineering Research Council of Canada (G.W.K.M.), Woods Hole Oceanographic Institution Arctic Initiative (J.Y.)

    Neutral sphingomyelinase mediates the co-morbidity trias of alcohol abuse, major depression and bone defects

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    Mental disorders are highly comorbid and occur together with physical diseases, which are often considered to arise from separate pathogenic pathways. We observed in alcohol-dependent patients increased serum activity of neutral sphingomyelinase. A genetic association analysis in 456,693 volunteers found associations of haplotypes of SMPD3 coding for NSM-2 (NSM) with alcohol consumption, but also with affective state, and bone mineralisation. Functional analysis in mice showed that NSM controls alcohol consumption, affective behaviour, and their interaction by regulating hippocampal volume, cortical connectivity, and monoaminergic responses. Furthermore, NSM controlled bone–brain communication by enhancing osteocalcin signalling, which can independently supress alcohol consumption and reduce depressive behaviour. Altogether, we identified a single gene source for multiple pathways originating in the brain and bone, which interlink disorders of a mental–physical co-morbidity trias of alcohol abuse—depression/anxiety—bone disorder. Targeting NSM and osteocalcin signalling may, thus, provide a new systems approach in the treatment of a mental–physical co-morbidity trias

    Economical impacts of alternatives to the castration of piglets without anaesthesia

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    The current practise of castrating piglets must be replaced by 2009. The economic viability of four alternative methods was examined: Rearing entire boars, vaccination against boar taint, anaesthesia by inhalation and anaesthesia by injection. The method used was a modified schema for the calculation of the gross margin in pig fattening. All economic affects, upstream and downstream the value chain, were integrated into the gross margin for pig fattening. All alternative methods led to a decrease of the gross margin. The reduction was moderate (2.30 to 3.70 SFr) with the vaccination against boar taint, with anaesthesia by inhalation in major and medium farms and with anaesthesia by injection. For small breeding farms, the gross margin was reduced by up to 10 SFr, mainly due to the high depreciation of the anaesthesia equipment. For these farms the question whether it will be feasible that several farms may commonly use one set of anaesthesia equipment is paramount. The costs of anaesthesia by injection are mainly determined by the price of the anaesthetic drug, thus there is no cost degression with increasing operation size. However, the price of the anaesthetic drug can, to this date, merely be estimated, as the product is not yet available on the market. The lower feed costs that are associated with the vaccination against boar taint cannot completely compensate for the cost of the vaccination drug and the expenses of two vaccinations. The increased percentage of lean meat of vaccinated boars can considerably influence their profitability. However, as the quality payment scheme in Switzerland is nonlinear, the aspects of carcass composition could not be incorporated into the comparison. The topic is picked up in annex 1. Fattening entire boars shows clear cost advantages (feed conversion, no costs for castration). However, the poor returns of carcasses affected by boar taint impact the profitability considerably. With a share of affected carcasses of 2.5%, the gross margin increases (marginally) by SFr. 0.10. However, with a share of 5% or 10% respectively, it decreases by SFr. 6.30 or 19.00, respectively. In the trials that have been conducted hitherto the share clearly exceeded 5%. As long as the part of tainted carcasses cannot be considerably decreased or as long as there is no better valorisation available for carcasses affected by boar taint, fattening of entire boars is not economically viable (exception: niche markets). The costs implied with the use of the electronic nose were estimated as a part of the calculation of the viability of fattening entire males. In major and medium slaughterhouses, the electronic nose can be used with moderate costs (up to SFr. 3.00/analysis). In medium slaughterhouses, however, this is only the case if the time that the carcasses are left to mature can be used for the analysis (no analysis in parallel to the slaughtering process). At the artisan slaughterer’s level, the electronic nose cannot be used in an economically viable way

    Mineralogia, química e micromorfologia de solos de uma microbacia nos tabuleiros costeiros do Espírito Santo

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    Solos dos tabuleiros costeiros do Estado do Espírito Santo foram estudados, com o objetivo de investigar e inter-relacionar suas características mineralógicas, químicas e micromorfológicas e fornecer subsídios para a reconstrução do ambiente pedogenético. Onze perfis de solos foram descritos, coletados e caracterizados analiticamente. Em amostras de perfis selecionados, determinou-se o Fe extraído pelo ditionito-citrato-bicarbonato de sódio. Determinou-se também o Fe menos cristalino pelo oxalato ácido de amônio e o Si amorfo pelo NaOH 0,5 mol L-1. Nas amostras de mosqueados e nódulos determinou-se a proporção de hematita e goethita e a substituição em Al na goethita. Análises mineralógicas foram realizadas por métodos óticos, difratometria de raios X e análise térmica diferencial. De amostras indeformadas dos horizontes subsuperficiais foram confeccionadas lâminas delgadas para análise micromorfológica. Constatou-se que o ambiente pedogenético atual está propiciando a estabilização da caulinita e formação de goethita, removendo a hematita e possivelmente sendo responsável pelo amarelecimento (xantização) dos horizontes superficiais. O processo de segregação de ferro é evidenciado pelo seu acúmulo nos nódulos e mosqueados em relação à matriz do solo, provavelmente por difusão, sendo a fonte a matriz. Os nódulos e mosqueados vermelhos estão em processo de destruição e não de formação. As gotículas de ferro, que com freqüência ocorrem no interior dos nódulos e concreções, constituem uma etapa do processo de formação ou destruição dessas estruturas

    The Age-Related Risk of Severe Outcomes Due to COVID-19 Infection: A Rapid Review, Meta-Analysis, and Meta-Regression

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    Increased age appears to be a strong risk factor for COVID-19 severe outcomes. However, studies do not sufficiently consider the age-dependency of other important factors influencing the course of disease. The aim of this review was to quantify the isolated effect of age on severe COVID-19 outcomes. We searched Pubmed to find relevant studies published in 2020. Two independent reviewers evaluated them using predefined inclusion and exclusion criteria. We extracted the results and assessed seven domains of bias for each study. After adjusting for important age-related risk factors, the isolated effect of age was estimated using meta-regression. Twelve studies met our inclusion criteria: four studies for COVID-19 disease severity, seven for mortality, and one for admission to ICU. The crude effect of age (5.2% and 13.4% higher risk of disease severity and death per age year, respectively) substantially decreased when adjusting for important age-dependent risk factors (diabetes, hypertension, coronary heart disease/cerebrovascular disease, compromised immunity, previous respiratory disease, renal disease). Adjusting for all six comorbidities indicates a 2.7% risk increase for disease severity (two studies), and no additional risk of death per year of age (five studies). The indication of a rather weak influence of age on COVID-19 disease severity after adjustment for important age-dependent risk factors should be taken in consideration when implementing age-related preventative measures (e.g., age-dependent work restrictions)

    Prevalence and predictors of MRSA carriage among employees in a non-outbreak setting: a cross-sectional study in an acute care hospital

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    Abstract Background Health care workers have an increased risk of being infected with Methicillin-resistant Staphylococcus aureus (MRSA), though little information is available about how prevalent (dormant) MRSA colonization is among health care workers. The aim of this study was to estimate the prevalence and predictors of MRSA carriage in a non-outbreak setting in a university hospital in Germany. Methods The entire staff of a university hospital heart center for cardiologic maximum medical care and cardiac surgery were invited to participate in a cross-sectional study (N = 575). The sampled population included health care workers as well as employees with no close patient contact. A questionnaire concerning personal and occupational risk factors as well as lifestyle and demographic factors was applied and nasal swabs were taken. In total 180 persons (31.3%) participated in the study. Results The majority of study participants had close contact to patients at work (n = 149, 82.8%). Thereof, about one-third had contact to MRSA-patients (n = 53, 35.6%), and most reported wearing protective clothing (n = 44, 83.0%). None of the administrative staff tested positive for MRSA and only one in 149 persons (0.7%, CI 0.00–0.02) with close patient contact carried MRSA (strain CC1-MRSA-IV). This person had close contact to patients with MRSA, less than 1 year of work experience, and had been treated with antibiotics within the last 12 months. Conclusion The results of our study suggest low point prevalence rates of MRSA colonization in health care workers in a non-outbreak setting
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