449 research outputs found

    A Lightweight High-sensitivity Chemical Mass Spectrometer for Organic Compounds

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    Comparing properties of natural biogenic with biomass burning particles in Amazonia.

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    The Large Scale Biosphere Atmosphere Experiment in\ud Amazonia (LBA) is a long-term (20 years) research effort\ud aimed at the understanding of the functioning of the\ud Amazonian ecosystem. The strong biosphere-atmosphere\ud interaction is a key component of the ecosystem functioning.\ud Two aerosol components are the most visible: The natural\ud biogenic emissions of particles and VOCs, and the biomass\ud burning emissions.\ud Two aerosol and trace gases monitoring stations were\ud operated for 4 years in Manaus and Porto Velho, two very\ud distinct sites, with different land use change. Manaus is a very\ud clean and pristine site and Porto Velho is representative of\ud heavy land use change in Amazonia. Aerosol composition,\ud optical properties, size distribution, vertical profiling and\ud optical depth were measured from 2008 to 2012. Aerosol\ud radiative forcing was calculated over large areas. It was\ud observed that the natural biogenic aerosol has significant\ud absorption properties. Organic aerosol dominates the aerosol\ud mass with 80 to 95%. Light scattering and light absorption\ud shows an increase by factor of 10 from Manaus to Porto\ud Velho. Very few new particle formation events were\ud observed. Strong links between aerosols and VOC emissions\ud were observed. Aerosol radiative forcing in Rondonia shows\ud a high -15 watts/m² during the dry season of 2010, showing\ud the large impacts of aerosol loading in the Amazonian\ud ecosystem. The increase in diffuse radiation changes the\ud forest carbon uptake by 20 to 35%, a large increase in this\ud important ecosystem

    A PRÁTICA DO ACOLHIMENTO NA ESTRATÉGIA SAÚDE DA FAMÍLIA

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    To analyze the practice of reception in the family health strategy using scientific evidence. Methods: This is a qualitative integrative literature review. The search for works involved in the research was carried out in the following databases: SCIELO, LILACS, BDENF and MEDLINE, using the descriptors in health sciences: "Welcoming", "Family health strategy" and "Humanization of care". The inclusion criteria were: published between 2014 and 2024, with free access to full texts, articles in Portuguese, English and Spanish and related to the theme. Exclusion criteria were: duplicate articles, incomplete articles, abstracts, reviews, debates, articles published in event proceedings and unavailable in full. Results: The practice of welcoming patients goes beyond qualified listening; this method of care is capable of identifying problems and promoting resolutive interventions. Conclusion: It can be concluded that welcoming is an important tool in the primary care process, since it is responsible for establishing a bond between members of the health team and users.Analisar por meio das evidências cientificas a prática do acolhimento na estratégia saúde da família. Métodos: Trata-se de uma revisão integrativa da literatura de caráter qualitativo. A busca dos trabalhos envolvidos na pesquisa foi realizada nas seguintes bases de dados: SCIELO, LILACS, BDENF e MEDLINE, a partir dos descritores em ciências da saúde: “Acolhimento”, “Estratégia saúde da família” e “Humanização da assistência”. Os critérios de inclusão foram: publicados no período entre 2014 e 2024, cujo acesso ao periódico era livre aos textos completos, artigos em idioma português, inglês e espanhol e relacionados a temática. Critérios de exclusão foram: artigos duplicados, incompletos, resumos, resenhas, debates, artigos publicados em anais de eventos e indisponíveis na íntegra. Resultados: A prática da realização do acolhimento vai além da escuta qualificada esse método de cuidado é capaz de identificar problemas e promover intervenções resolutivas. Conclusão: Conclui-se que o acolhimento é uma ferramenta importante no processo de cuidado na atenção primária, visto que, ele é responsável pelo estabelecimento de vínculo entre os membros da equipe de saúde e os usuários

    Intercomparison and characterization of 23 Aethalometers under laboratory and ambient air conditions : procedures and unit-to-unit variabilities

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    Aerosolized black carbon is monitored worldwide to quantify its impact on air quality and climate. Given its importance, measurements of black carbon mass concentrations must be conducted with instruments operating in quality-checked and ensured conditions to generate data which are reliable and comparable temporally and geographically. In this study, we report the results from the largest characterization and intercomparison of filter-based absorption photometers, the Aethalometer model AE33, belonging to several European monitoring networks. Under controlled laboratory conditions, a total of 23 instruments measured mass concentrations of black carbon from three well-characterized aerosol sources: synthetic soot, nigrosin particles, and ambient air from the urban background of Leipzig, Germany. The objective was to investigate the individual performance of the instruments and their comparability; we analyzed the response of the instruments to the different aerosol sources and the impact caused by the use of obsolete filter materials and the application of maintenance activities. Differences in the instrument-to-instrument variabilities from equivalent black carbon (eBC) concentrations reported at 880 nm were determined before maintenance activities (for soot measurements, average deviation from total least square regression was -2.0% and the range -16% to 7 %; for nigrosin measurements, average deviation was 0.4% and the range -15% to 17 %), and after they were carried out (for soot measurements, average deviation was 1:0% and the range -14% to 8 %; for nigrosin measurements, the average deviation was 0.5% and the range -12% to 15 %). The deviations are in most of the cases explained by the type of filter material employed by the instruments, the total particle load on the filter, and the flow calibration. The results of this intercomparison activity show that relatively small unit-to-unit variability of AE33-based particle light absorbing measurements is possible with well-maintained instruments. It is crucial to follow the guidelines for maintenance activities and the use of the proper filter tape in the AE33 to ensure high quality and comparable black carbon (BC) measurements among international observational networks.Peer reviewe

    Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

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    The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

    Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

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    Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

    The Amazon Tall Tower Observatory (ATTO): Overview of pilot measurements on ecosystem ecology, meteorology, trace gases, and aerosols

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    The Amazon Basin plays key roles in the carbon and water cycles, climate change, atmospheric chemistry, and biodiversity. It has already been changed significantly by human activities, and more pervasive change is expected to occur in the coming decades. It is therefore essential to establish long-term measurement sites that provide a baseline record of present-day climatic, biogeochemical, and atmospheric conditions and that will be operated over coming decades to monitor change in the Amazon region, as human perturbations increase in the future. The Amazon Tall Tower Observatory (ATTO) has been set up in a pristine rain forest region in the central Amazon Basin, about 150 km northeast of the city of Manaus. Two 80 m towers have been operated at the site since 2012, and a 325 m tower is nearing completion in mid-2015. An ecological survey including a biodiversity assessment has been conducted in the forest region surrounding the site. Measurements of micrometeorological and atmospheric chemical variables were initiated in 2012, and their range has continued to broaden over the last few years. The meteorological and micrometeorological measurements include temperature and wind profiles, precipitation, water and energy fluxes, turbulence components, soil temperature profiles and soil heat fluxes, radiation fluxes, and visibility. A tree has been instrumented to measure stem profiles of temperature, light intensity, and water content in cryptogamic covers. The trace gas measurements comprise continuous monitoring of carbon dioxide, carbon monoxide, methane, and ozone at five to eight different heights, complemented by a variety of additional species measured during intensive campaigns (e.g., VOC, NO, NO2, and OH reactivity). Aerosol optical, microphysical, and chemical measurements are being made above the canopy as well as in the canopy space. They include aerosol light scattering and absorption, fluorescence, number and volume size distributions, chemical composition, cloud condensation nuclei (CCN) concentrations, and hygroscopicity. In this paper, we discuss the scientific context of the ATTO observatory and present an overview of results from ecological, meteorological, and chemical pilot studies at the ATTO site. © Author(s) 2015

    Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

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    Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis
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