161 research outputs found

    Application of different geothermometrical techniques to a low enthalpy thermal system

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    The reservoir temperature of the waters in the low temperature carbonate-evaporitic geothermal system of Arnedillo has been estimated by using two different techniques: 1) chemical geothermometers and 2) geothermometrical modelling. By combining the results of both techniques a reliable range of temperature of 90 ± 20 oC has been proposed for the waters in the reservoir. Despite being a carbonate-evaporitic system, the cationic geothermometers have provided good results, which, together with the geothermometrical modelling, indicate that the waters have reached equilibrium with anhydrite, quartz, calcite, dolomite, albite and K-feldspar in the reservoir

    Geochemical evolution of thermal waters in carbonate – evaporitic systems: The triggering effect of halite dissolution in the dedolomitisation and albitisation processes

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    The Fitero and Arnedillo geothermal systems are located in the NW part of the Iberian Range (Northern Spain). The geothermal reservoir is hosted in the Lower Jurassic carbonates, in contact with the evaporitic Keuper Facies. Thermal waters are of chloride-sodium type with discharge temperature of about 45 °C and near neutral pH. The Arnedillo waters are more saline with higher Na, Cl and sulphate contents, but lower Ca and Mg than the Fitero waters. All waters have attained mineral equilibrium at depth with calcite, dolomite, anhydrite, quartz, albite, K-feldspar and other aluminosilicates, except for the Fitero waters, which have not reached the equilibrium with the aluminosilicates. The calculated reservoir temperature is 81 ± 11 °C in Fitero and 87 ± 13 °C in Arnedillo. In order to identify the reasons for the differences found between the two systems some inverse and forward geochemical calculations were performed and the main water-rock interaction processes responsible for the chemical evolution of these waters have been evaluated. Halite dissolution has been found to be the triggering factor for the two most important geochemical processes in the system: a) albitisation process, due to the common ion effect (Na); and b) dedolomitisation process, associated with the salinity increase, which enhance the dissolution of anhydrite and, in turn, produces the precipitation of calcite (common ion effect, Ca) and the concomitant dissolution of dolomite. Halite dissolution may be an important driving force in the geochemical evolution of groundwater systems in contact with carbonates and evaporites, where equilibrium with K-feldspar, albite and anhydrite has already been attained. The evolution of the processes at pH, temperature and salinity ranges wider than those in the Fitero-Arnedillo system has been theoretically examined with additional reaction-path simulations, in order to generalise the geochemical behaviour of these processes in other environments

    Comparison of different thermodynamic databases used in a geothermometrical modelling calculation

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    Different thermodynamic databases usually have common thermodynamic data for some minerals or aqueous species, but in many cases they present important differences. Four different thermodynamic databases (WATEQ4F, LLNL, DATA0.YMP.R5 and SOLTHERM) have been used in a geothermometrical modelling problem and they are compared in this work. The main differences found in the thermodynamic data are related to the order, degree, crystallinity and composition of the considered aluminosilicate phases and the effects of these properties in the experimental, or theoretical, data used for the fitting of the equilibrium constant at different temperatures

    Relation among Caregivers’ Burden, Abuse and Behavioural Disorder in People with Dementia

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    Dementia produces a loss of independence to carry out the activities of daily life. The great demand for care that these people need usually falls on the family through informal care. This study aims to analyse the burden showed by the informal caregiver of a person with dementia. In addition, we analyse whether this burden present in informal caregivers could be related to abusive behaviour. We also study the relationship between the stage of the disease, the appearance of behavioural disorders and the level of burden in the caregiver using the Scales of Zarit, CASE and FAST. The data showed that 45.50 per cent of caregivers have light burden or burden. After the research, it was identified that the presence of behavioural disorders in patients with dementia showed a correlation with the increase in both the main caregiver burden and abuse. An increase in the level of burden is followed by an increase in the level of abuse (r = 0.844; p = 0.000). Furthermore, we analysed several conditions that could have a correlation with this burden and abuse. It was found that burden in the caregiver could be linked with the presence of behavioural disorders, like aggression (r = 0.577; p = 0.008) and irritability (r = 0.600; p = 0.005) at the moderate stage of the disease. On the other hand, there is a positive correlation between the probability that people with dementia suffer abuse in the moderate stage of the disease and the presence of aggression (r = 0.732; p = 0.000), lack of inhibition (r = 0.571; p = 0.009) and irritability (r = 0.827; p = 0.000). Taking this data into account, burden and abuse seem to be linked to the presence of behavioural disorders in patients with dementia in the moderate stage

    Salinity contamination response to changes in irrigation management. Application of geochemical codes

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    Salinity contamination caused by irrigation has been widely studied but the analysis of geochemical processes regarding agronomic variables has not adequately been considered yet. The research presented here analyzes the influence of changes in irrigation management on salinity contamination, through the use of geochemical modeling techniques, in an agricultural basin during the hydrological year of 2001 and within the period 2005-2008. The results indicate that the changes implemented in irrigation management reduced the masses of salts exported in 72%, although water salinity increased by 25% (this salinity level does not restrict its use for irrigation). The different ionic ratios in drainage water, the results of the salinity balances, and the results of geochemical calculations (mass balances and speciation-solubility) indicate, mainly, precipitation of calcite, dissolution of gypsum and halite and cation exchange. The salt contamination index decreased from approximately 70% to levels close to those presented in modern irrigation areas, indicating that the changes in irrigation management were effective. Petrocalcic genesis and punctual sodification of soils can constitute an agroenvironmental problem that requires adequate management of irrigation and drainage considering future modernization of irrigation areas

    Gold(I) complexes bearing alkylated 1, 3, 5-triaza-7-phosphaadamantane ligands as thermoresponsive anticancer agents in human colon cells

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    Overheating can affect solubility or lipophilicity, among other properties, of some an-ticancer drugs. These temperature-dependent changes can improve efficiency and selectivity of the drugs, since they may affect their bioavailability, diffusion through cell membrane or activity. One recent approach to create thermosensitive molecules is the incorporation of fluorine atoms in the chemical structure, since fluor can tune some chemical properties such as binding affinity. Herein we report the anticancer effect of gold derivatives with phosphanes derived from 1, 3, 5-triaza-7-phosphaadamantane (PTA) with long hydrocarbon chains and the homologous fluorinated chains. Besides, we analysed the influence of temperature in the cytotoxic effect. The studied gold(I) complexes with phosphanes derived from PTA showed antiproliferative effect on human colon carcinoma cells (Caco-2/TC7 cell line), probably by inhibiting cellular TrxR causing a dysfunction in the intracellular redox state. In addition, the cell cycle was altered by the activation of p53, and the complexes produce apoptosis through mitochondrial depolarization and the consequent activation of caspase-3. Furthermore, the results suggest that this cytotoxic effect is enhanced by hyperthermia and the presence of polyfluorinated chains. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

    Methodology for Hydrogeochemical Sampling to Characterise Groundwaters in Crystalline Bedrock: Developments Made within the Swedish Radwaste Programme

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    The search by SKB (Swedish Nuclear Fuel and Waste Management Co.) for a site to locate the deep geological repository for spent nuclear fuel in Sweden has involved geoscientific investigations at several locations since the 1970s. The objectives were to characterise geologically a bedrock volume as well as its hydrogeology and hydrochemistry. To acquire high-quality hydrogeochemical data, a complete system for groundwater sampling and analysis, as well as for interpretation strategies, has been developed through a continuous process of modification and refinement. Since the largest part of the Swedish bedrock is composed of granitoids, the site investigations had to adapt to the special difficulties of fractured crystalline rocks. This paper discusses the problems with groundwater sampling that are specific to fractured crystalline rocks and describes the solutions adopted and methods developed by SKB since the early 2000s during the site investigations. The methodology described in this paper for the characterisation of deep groundwaters in crystalline rocks is not only applicable in the context of radioactive waste disposal but also useful when sampling groundwaters for any purpose in such rocks. Sampling of groundwaters in fractured rocks at depth, often down to approximately 1, 000 m, involves special challenges since the natural conditions of the groundwater are easily disturbed, especially by the initial drilling, but also by every subsequent activity performed in the borehole, including the actual groundwater sampling. The sampling strategy presented in this paper shows that planning of the sampling preferably starts already when the drilling procedure is decided. Each following step is described in detail and includes tracing the drilling fluid, selecting the best borehole sections to sample, procedures for the actual sampling, and selection of analytical protocol; all this with the goal of taking representative samples. Although the evaluation of the sampling uncertainties is not a straightforward procedure, an adequate categorisation routine has been established to classify groundwater samples regarding sample quality, representativeness, and suitability for further interpretations and modelling

    Polypharmacy in older adults with human immunodeficiency virus infection compared with the general population

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    Background: The percentage of older HIV-positive patients is growing, with an increase in age-related comorbidities and concomitant medication. Objectives: To quantify polypharmacy and profile types of non-antiretroviral drugs collected at community pharmacies in 2014 by HIV-positive individuals on antiretroviral therapy and to compare these findings with those of the general population. Methods: HIV-positive patients (n=199) were compared with a group of patients from the general population (n=8, 172), aged between 50 and 64 years. The factors compared were prevalence of polypharmacy (=5 comedications with cumulative defined daily dose DDD] per drug over 180), percentage of patients who collected each therapeutic class of drug, and median duration for each drug class (based on DDD). Results were stratified by sex. Results: Polypharmacy was more common in HIV-positive males than in the male general population (8.9% vs 4.4%, P=0.010). Polypharmacy was also higher in HIV-positive females than in the female general population (11.3% vs 3.4%, P=0.002). Percentage of HIV-positive patients receiving analgesics, anti-infectives, gastrointestinal drugs, central nervous system (CNS) agents, and respiratory drugs was higher than in the general population, with significant differences between male populations. No differences were observed in proportion of patients receiving cardiovascular drugs. The estimated number of treatment days (median DDDs) were higher in HIV-positive males than in males from the general population for anti-infectives (32.2 vs 20.0, P<0.001) and CNS agents (238.7 vs 120.0, P=0.002). A higher percentage of HIV-positive males than males from the general population received sulfonamides (17.1% vs 1.5%, P, 0.001), macrolides (37.1% vs 24.9%, P=0.020), and quinolones (34.3% vs 21.2%, P=0.009). Conclusion: Polypharmacy is more common in HIV-positive older males and females than in similarly aged members of the general population. HIV-positive patients received more CNS drugs and anti-infectives, specifically sulfonamides, macrolides, and quinolones, but there were no differences in the percentage of patients receiving cardiovascular drugs. It is essential to investigate nonantiretroviral therapy medication use in the HIV-positive population to ensure these patients receive appropriate management

    Drugs use in pregnancy in the Valencia Region and the risk of congenital anomalies

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    Background Despite the potential risks of drug use during pregnancy, consumption has increased in recent decades. Objective To identify the risk of congenital anomalies (CA) associated with the use of drugs in primary care in pregnant women resident in the Valencia Region. Methods A case-control study, considering a case as a less than one year old live birth in 2009–2010, diagnosed with a CA and resident in the Valencia Region, obtained from the CA population-based registry. Controls were selected from the Metabolic Disease Registry, and the drugs prescribed and dispensed from the Integral Management of Pharmaceutical Services. Crude odds ratio (OR) was calculated with its 95% confidence intervals and adjusted OR was calculated using logistic regression. Results A total of 1.913 cases and 3.826 controls were identified. The most frequently used drug groups were those acting on the musculoskeletal, nervous and respiratory systems, on the blood and blood forming organs, and anti-infection drugs. The most common drugs used were ibuprofen, dexketoprofen, paracetamol, amoxicillin, ferrous sulphate, and a combination of folic acid. A significantly increased risk of CA was identified for drugs acting on the musculoskeletal system (adjusted OR 1.14 [95% confidence interval 1.02–1.28]). A significantly decreased risk was observed for drugs acting on the blood and blood forming organs (adjusted OR 0.87 [95% confidence interval 0.78–0.98]). Conclusions Associations between drugs and CA in pregnant women resident in the Valencia Region have been identified for drugs that act as risk factors of CA, and for drugs that act as protective factors of CA. Antecedentes El consumo de medicamentos durante el embarazo se ha incrementado en las últimas décadas. Objetivo Identificar el riesgo de anomalías congénitas (AC) asociado a la utilización de medicamentos en atención ambulatoria en embarazadas residentes en la Comunitat Valenciana. Métodos Estudio de casos-controles, considerando caso a menores de un año nacidos vivos en 2009-2010 diagnosticados de AC y residentes en la Comunitat Valenciana, obtenidos del registro poblacional de AC. Los controles se seleccionaron del Registro de Metabolopatías y la medicación prescrita y dispensada se obtuvo del módulo Gestión Integral de Prestación Farmacéutica. Se calcularon las odds ratio (OR) y los intervalos de confianza al 95% y las OR ajustadas mediante regresión logística. Resultados Se identificaron 1.913 casos y 3.826 controles. Los grupos de medicamentos más frecuentemente prescritos y dispensados fueron: los que actúan sobre los sistemas musculoesquelético, nervioso, respiratorio, sobre la sangre y órganos hematopoyéticos, y antiinfecciosos. Los medicamentos más habituales fueron: ibuprofeno, dexketoprofeno, paracetamol, amoxicilina, sulfato de hierro y una combinación de ácido fólico. Se identificó un aumento del riesgo de anomalías congénitas significativo para los fármacos de acción sobre el sistema musculoesquelético (OR ajustada de 1,14 [intervalo de confianza al 95% 1,02-1,28]). Se observó una disminución del riesgo significativa en el grupo que actúa sobre la sangre y los órganos hematopoyéticos (OR ajustada de 0,87 [intervalo de confianza al 95% 0,78-0,98]). Conclusiones Se han identificado asociaciones de medicamentos con AC en mujeres embarazadas residentes en la Comunitat Valenciana, tanto para fármacos que actúan como factores de riesgo de AC como para fármacos que actúan como factores protectores de AC

    La validez del Conjunto Mínimo Básico de Datos como fuente de identificación de las anomalías congénitas en la Comunitat Valenciana

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    Objetivo Evaluar la validez del Conjunto Mínimo Básico de Datos (CMBD) para identificar anomalías congénitas mayores en la Comunitat Valenciana. Métodos Se realizó un estudio epidemiológico retrospectivo. Del CMBD se seleccionaron las altas en menores de un año nacidos en 2007, residentes en la Comunitat Valenciana con código de anomalía congénita (740-759 CIE9-MC) y una muestra aleatoria de menores de un año sin altas con estos códigos. Tras revisar la documentación clínica, se clasificaron como verdaderos positivos y negativos y falsos positivos y negativos. Se calcularon el valor predictivo positivo y negativo y la sensibilidad. Se analizaron la concordancia de los diagnósticos entre el CMBD y la documentación clínica utilizando la prueba kappa. Resultados Se identificaron 2305 altas de 1651 pacientes. En los 544 pacientes de la muestra, 4 tenían alguna anomalía congénita mayor. El valor predictivo positivo fue del 56,4% (intervalo de confianza del 95% [IC95%]: 53,9-58,8) y el negativo fue del 99,3% (IC95%: 98,6-100,0). La sensibilidad del CMBD fue del 68,6% (IC95%: 66,1-71,1). Los códigos más frecuentes en los verdaderos positivos fueron: 745.5 (Comunicación interauricular), 745.4 (Comunicación interventricular) y 747.0 (Ductus arterioso persistente), y en los falsos positivos: 747.0, 745.5 y 752.51 (Criptorquidia). El 25,5% de los diagnósticos con anomalía congénita del CMBD no estaban en la historia clínica. Considerando todos los diagnósticos codificados en el CMBD, la concordancia fue de 0,70 (IC95%: 0,68-0,72). Conclusiones El CMBD es la principal fuente de información para la identificación de casos para el Registro Poblacional de Anomalías Congénitas de la Comunitat Valenciana, pero su principal limitación es el elevado número de casos falsos positivos que detecta. Objective To assess the validity of the Spanish Minimum Basic Data Set (MBDS) for identifying major congenital anomalies in the Valencian Community. Methods A retrospective epidemiological study was carried out. Children under the age of one year, born in 2007 and residing in the Valencian Community with congenital anomalies code 740-759 CIE9-MC, were selected from the MBDS, in addition to a random sample of children under the age of 1 year without these discharge codes. Having reviewed the clinical documentation, the cases were classified as true positives and negatives and false positives and negatives. Positive and negative predictive value and sensitivity were calculated. The kappa test was applied to analyse diagnostic consistency between the MBDS and the clinical documentation. Results A total of 2305 discharges of 1651 patients were identified. 4 out of the 5434 patients sampled had a major congenital abnormality. The positive predictive value was 56.4% (95% confidence interval [95%CI]: 53.9-58.8) and the negative predictive value was 99.3% (95%CI: 98.6-100.0). MBDS sensitivity was 68.6% (95%CI: 66.1-71.1). The most common codes in the true positives were: 745.5 (atrial septal defect), 745.4 (ventricular septal defect) and 747.0 (patent ductus arteriosus) and in the false positives: 747.0, 745.5 and 752.51 (cryptorchidism). 25.5% of diagnoses with congenital anomaly from the MBDS were not in the clinical documentation. Considering all diagnoses coded in the MBDS, the correlation was 0.70 (95%CI: 0.68-0.72) Conclusions The MBDS is the main source of information to detect cases in the registry of congenital anomalies of the Valencian Community. Its main limitation is the high number of false positive cases detected
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