996 research outputs found

    Use of TG-DSC-MS and gas analyzer data to investigate the reaction of CO2 and SO2 with Ca(OH)2 at low temperature

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    To investigate the reaction of calcium hydroxide with CO2 and SO2 simultaneously, a gas containing both gases reacted with the calcium base at 58 ºC and a relative humidity of 55 %. Different CO2 and SO2 concentrations were performed being the composition of the gas stream 12, 6 or 0 % CO2; 5000, 2500, 1000 or 0 ppm SO2, 9.5 % synthetic air and balanced N2, with a flue gas rate of 1000 mL/minute. A continuous gas analyzer controlled the CO2 and SO2 concentrations in the effluent gas and the breakthrough curves of both gases were obtained. The gas analyzer data show that SO2 and CO2 compete to react with the base reacting simultaneously. By using thermogravimetry (TG), differential scanning calorimetry (DSC) and mass spectrometry (MS) techniques, calcium sulphite hemihydrate, CaSO3.1/2H2O, was identified as the unique desulfurization product detected. CaSO4 was not identified although O2 was present in the gas mixture. CaCO3 was the main product of the reaction of calcium hydroxide and CO2 being the complex CaO.CO2 another possible product synthesized in low amounts. From analyzer data it was proved that a part of the CaCO3 present in the sorbent or synthesized in the process reacts with the SO2 and release CO2. Results of this work show that the combination of continuous gas analyzer data and TG-DSC-MS techniques, not used before to study this reaction, is a good and easy way to clarify the process and the products of reaction.Our acknowledgment to M.C. y T. for financial support of this work under Project MAT 2010-18862

    X-ray difraction analysis of desulfurant sorbents prepared by mixing calcined sewage sludge and CaO in distilled or seawater

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    Desulfurant sorbents prepared by hydration, in sea or distilled water, of calcined sewage sludge (ash) and CaO at CaO/ash weight ratios of 0.2 or 3 at room temperature or at 90 º C, were characterized by X-ray diffraction in order to relate the X-ray composition of the sorbents to the preparation process and to the specific surface area of the obtained sorbents. Results show that the main compounds detected in the sludge´s ash are the same than those found in bibliography for the calcined sludge. In all the sorbents, independently of the preparation conditions, Ca(OH)2 was found instead of CaO used as raw material. New and different crystalline products were found in the sorbents depending on the preparation conditions. All the sorbents prepared in seawater contain NaCl in their composition; the specific surface area of the sorbents increased with hydration time and temperature and was lower when seawater was used for hydration.We are thankful to MICINN in Spain, National Plan for scientific Research, Development and innovation, for financial support under Project: MAT2010-18862

    Study of the thermal behavior of sewage sludge from a WWTP in Cantabria (Spain) by TG-DSC-MS

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    According to European Directive and national regulations in Spain, techniques based on thermal decomposition are proposed for the sewage sludge disposal. In this work, the sludge from the wastewater treatment plant (WWTP) of Casar de Periedo, in Cantabria (Spain) is studied by Thermogravimetry – Differential Scanning Calorimetry – Mass Spectrometry (TG –DSC – MS). A sample of this sludge was submitted, after drying, to different atmospheres: 100 % He, N2 /air or He/air 80/20 and 100 % air, from 20 to 900 ºC, to study primary decomposition reactions in pyrolysis, gasification and combustion respectively. The purpose was to determine the weight loss at different temperatures, the heat flow at each atmosphere and the presence of some gas products like H2, CO, CO2, CH4, or HCl, SO2, SO3, NO and NO2 released, these last five gases to know the contaminants emitted. Combustion conditions (air) rend the greatest mass loss and energy production. Reactions take place at lower temperatures, being mainly CO2 and H2O the products detected in MS, with little amounts of CH4, as it is expected for mainly total oxidation reactions. In gasification conditions, essayed with two atmospheres (N2-air and He-air), quantitative results found are similar, but the highest thermal conductivity of He produces exothermic reactions at lower temperatures, observed in the mass loss and heat flow profiles. From reactions of decomposition, partial oxidation and total oxidation, CO2, H2, H2O and CH4, were identified by MS. Pyrolysis conditions (He) produce the lowest mass loss and slightly endothermic reactions, mainly because of decomposition reactions. Higher H2 amounts were obtained at higher temperatures than in gasification conditions. No gas contaminant (HCl, SO2, SO3, NO and NO2) has been detected by MS, considering this sewage sludge as a “clean sludge”. Comparing the thermal behaviour of the sewage sludge of this plant to that obtained in the WWTP of Santander, the sludge from Casar de Periedo is more appropriated to thermal valorization.We are thankful to MICINN in Spain, National Plan for scientific Research, Development and innovation, for financial support under Project: MAT2010-18862

    Cytogenetics of the razor clam "Solen marginatus" (Mollusca: Bivalvia: Solenidae)

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    [Abstract:] The razor clam Solen marginatus has a diploid chromosome number of 38. The karyotype consists of one metacentric/submetacentric, three submetacentric/metacentric, five submetacentric, one submetacentric/subtelocentric, one subtelocentric/submetacentric, six subtelocentric and two telocentric chromosome pairs. Staining with chromomycin A3 revealed bright positive bands subcentromerically in the long arms of one medium-sized subtelocentric pair, while DAPI staining showed uniform fluorescence in all chromosomes of the complement. Fluorescence in situ hybridization using an 18S-5.8S-28S rDNA probe locates these loci at the subcentromeric region of one subtelocentric pair and at the subtelomeric region of another subtelocentric pair.Xunta de Galicia; PGIDT99 MAR1030

    Genome sizes and karyotypes in the razor clams "Ensis arcuatus" (Jeffreys, 1865) and "E. siliqua" (Linnaeus, 1758)

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    [Abstract] The razor clams Ensis arcuatus and E. siliqua show a diploid DNA content of 3.85 ± 0.049 pg and 4.00 ± 0.050 pg, respectively. Both have a diploid chromosome number of 38 although their karyotypes show remarkable differences. The karyotype of E. arcuatus consists of 4 metacentric, 1 metacentric-submetacentric, 7 submetacentric and 7 telocentric chromosome pairs, whereas that of E. siliqua possesses 3 metacentric, 7 submetacentric and 9 telocentric pairs. In situ hybridization using an 18S-5.8S-28S rDNA probe located this ribosomal locus on one chromosome pair for both species. Results demonstrate that large differences exist between them, probably caused by chromosome rearrangements along evolution of these two species, and increase the number of studies on bivalve cytogenetics.Xunta de Galicia; PGIDT99 MAR1030

    The Effectiveness of Advanced Practice Nurses with Respect to Complex Chronic Wounds in the Management of Venous Ulcers

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    This study aims to evaluate the effectiveness of advanced practice nurses with respect to complex chronic wounds (APN-CCWs) in the care of patients with venous ulcers. A multicentric, quasi-experimental pre-post study was conducted without a control group in the sanitary management areas where the APN-CCW program is being piloted. The intervention consisted of a mass training of clinical nurses from the participating districts on the proper management of injuries and the use of compression therapy. The data were collected through a specifically constructed questionnaire with questions regarding descriptive variables of injuries and their treatment. A total of 643 professionals responded (response rate of 89.1%), attending to a total population of 707,814 inhabitants. An increase in multilayer bandage use by 15.67%, an increase in elastic bandage use by 13.24%, and a significant decrease in the referral of patients to consultation with hospital specialists was achieved, from 21.08% to 12.34%. The number of patients referred to the APNs was 13.25%, which implied a resolution rate of 94.08% of their injuries. In conclusion, the coordination by the APN-CCWs in patients with venous ulcers was effective in improving the continuity of care, in the optimization of resources, and in their care role

    The CHROMEVALOA Database: A Resource for the Evaluation of Okadaic Acid Contamination in the Marine Environment Based on the Chromatin-Associated Transcriptome of the Mussel Mytilus galloprovincialis

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    Okadaic Acid (OA) constitutes the main active principle in Diarrhetic Shellfish Poisoning (DSP) toxins produced during Harmful Algal Blooms (HABs), representing a serious threat for human consumers of edible shellfish. Furthermore, OA conveys critical deleterious effects for marine organisms due to its genotoxic potential. Many efforts have been dedicated to OA biomonitoring during the last three decades. However, it is only now with the current availability of detailed molecular information on DNA organization and the mechanisms involved in the maintenance of genome integrity, that a new arena starts opening up for the study of OA contamination. In the present work we address the links between OA genotoxicity and chromatin by combining Next Generation Sequencing (NGS) technologies and bioinformatics. To this end, we introduce CHROMEVALOAdb, a public database containing the chromatin-associated transcriptome of the mussel Mytilus galloprovincialis (a sentinel model organism) in response to OA exposure. This resource constitutes a leap forward for the development of chromatin-based biomarkers, paving the road towards the generation of powerful and sensitive tests for the detection and evaluation of the genotoxic effects of OA in coastal areas

    Caracterización de las reacciones adversas por alimentos en un servicio hospitalario de alergia

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    Introducción: Las reacciones adversas por alimentos están aumentando en todo el mundo, y constituyen un problema de salud que afecta la calidad de vida de aquellos que las padecen. Objetivo: Caracterizar las reacciones adversas por alimentos en pacientes atendidos en el servicio de Alergia, para diseñar estrategias de intervención que permitan su prevención y un adecuado tratamiento. Métodos: Estudio descriptivo de corte transversal que incluyó 116 pacientes adultos atendidos en el servicio de Alergia del Hospital Universitario "General Calixto García", durante el periodo comprendido entre marzo 2017 y febrero 2019. A los pacientes se les realizó historia clínica e interrogó mediante cuestionario elaborado para el estudio, luego que dieran su consentimiento por escrito. Resultados: La rinitis alérgica fue el antecedente que prevaleció en los pacientes (47 %) y el asma en los familiares (41 %). Las manifestaciones cutáneas fueron las más frecuentes (79 %), seguidas de las digestivas (50 %). Los alimentos más implicados fueron los mariscos (42 %) y el pescado (40 %). La mayoría de las reacciones se presentaron en el propio hogar del paciente (86 %) y en menos de una hora (71 %). La combinación de antihistamínicos y esteroides (57 %) fue la más utilizada como medicamentos en dicho tratamiento. Conclusiones: Las reacciones por alimentos predominaron en el sexo femenino y se asociaron a enfermedad alérgica, en casi la mitad de los casos. Los mariscos y pescados fueron los principales alimentos causales. Se requiere investigar sobre los factores de riesgo y la prevalencia de reacciones adversas a los alimentos en la población cubana

    SAFARI optical system architecture and design concept

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    SpicA FAR infrared Instrument, SAFARI, is one of the instruments planned for the SPICA mission. The SPICA mission is the next great leap forward in space-based far-infrared astronomy and will study the evolution of galaxies, stars and planetary systems. SPICA will utilize a deeply cooled 2.5m-class telescope, provided by European industry, to realize zodiacal background limited performance, and high spatial resolution. The instrument SAFARI is a cryogenic grating-based point source spectrometer working in the wavelength domain 34 to 230 μm, providing spectral resolving power from 300 to at least 2000. The instrument shall provide low and high resolution spectroscopy in four spectral bands. Low Resolution mode is the native instrument mode, while the high Resolution mode is achieved by means of a Martin-Pupplet interferometer. The optical system is all-reflective and consists of three main modules; an input optics module, followed by the Band and Mode Distributing Optics and the grating Modules. The instrument utilizes Nyquist sampled filled linear arrays of very sensitive TES detectors. The work presented in this paper describes the optical design architecture and design concept compatible with the current instrument performance and volume design drivers

    Effect of statin use on outcomes of adults with candidemia

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    Background: Statins have immunomodulatory properties and hinder Candida growth. However, it is unknown whether they may improve prognosis in patients with candidemia. We sought to determine the effect of prior statin use on the clinical outcomes of patients suffering candidemia. Methods and Findings: Multicenter cohort study of hospitalized adults with candidemia between 2005 and 2011 in six hospitals in Spain, Brazil and Argentina. Of 326 candidemias, 44 (13.5%) occurred in statin users and 282 (86.5%) in statin non-users. The median value of APACHE II at candidemia diagnosis was similar between groups (18 vs. 16; p=.36). Candida albicans was the most commonly isolated species, followed by C. parapsilosis, C. tropicalis, C. glabrata, and C. krusei. There were no differences regarding appropriate empirical antifungal treatment. Statin users had a lower early (5 d) case-fatality rate than non-users (4.5 vs. 17%; p=.031). This effect was not observed with other cardiovascular drugs (aspirin, beta blockers and ACE inhibitors). Independent factor related to early case-fatality rate was APACHE II score (AOR, 1.08; 95% CI, 1.03-1.14; p=.002). An appropriate empirical antifungal therapy (AOR, 0.11; 95% CI, 0.04-0.26; p=<.001) and prior statin use were independently associated with lower early case-fatality (AOR, 0.17; 95% CI, 0.03-0.93; p=.041). Fourteen days (14d) and overall (30d) case-fatality rates were similar between groups (27% vs. 29%; p=0.77 and 40% vs. 44%; p=.66). Conclusions: The use of statins might have a beneficial effect on outcomes of patients with candidemia. This hypothesis deserves further evaluation in randomized trials
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