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Abstract: To investigate the possible variations of Rn concentration in crystalline rocks as a function of flow conditions, a field study was carried out of a fractured aquifer in granite. The method is based on the in situ measurement of Rn in groundwater, aquifer tests for the determination of hydraulic characteristics of the aquifer and laboratory measurement of Rn exhalation rate from rocks. A simple crack model that simulates the Rn concentration in waters circulating in a fracture intersecting a borehole was also tested. The Rn concentrations in groundwaters from boreholes of the study site ranged from 192 to 1597BqL−1. The Rn exhalation rates of selected samples of granite and micaschist were determined from laboratory experiments. The results yielded fluxes varying from 0.5 to 1.3mBqm−2 s−1 in granite and from 0.5 to 0.9mBqm−2 s−1 in micaschists. Pumping tests were performed in the studied boreholes to estimate the transmissivity and calculate the equivalent hydraulic aperture of the fractures. Transmissivities ranged from 10−5 to 10−3 m2 s−1. Using the cubic law, hydraulic equivalent fracture apertures were calculated to be in the range of 0.5–2.3mm. To gain a better insight into the spatial variability of Rn contents in groundwater, theoretical Rn concentrations were calculated from an available simple crack model using results from field and laboratory experiments. This model gave satisfactory results for boreholes characterized by low-flow conditions, in which case, the calculated Rn contents were in the range of Rn concentrations set by the analytical uncertainty of concentrations measured in water. However, for boreholes characterized by high-flow conditions, the model underestimated the Rn concentration in groundwater. The higher the flow in the fracture, the larger the difference between calculated and measured Rn concentrations in water. These observations led to performing pumping tests to obtain a better understanding of the hydrogeological control of Rn content in water. The results clearly show an increase of Rn content in groundwater after the pumping test, which could be explained by the input of Rn-rich waters from the host matrix. [Copyright &y& Elsevier]

Volcanism can cause major impacts, including climate change and mass extinctions. However, the impact of monogenetic volcanism is often considered as limited in volcanological research. This work provides for the first time an interdisciplinary approach to the socio-ecological impact of monogenetic volcanism in a key region, the La Garrotxa Volcanic Field (GVF, Girona, NE Iberia), where intense monogenetic volcanic activity occurred in the past. The analyses of a sedimentary sequence from the GVF enabled identifying previously unknown volcanic eruptions in the time interval 14-8.4 ka cal BP, constrain their volcanic stratigraphy and age, and unfold the effects of environmental change on geomorphology, vegetation, aquatic organisms and humans. Moreover, we reconstruct the major palaeoenvironmental changes caused by the eruptions in terms of fire episodes and subsequent disturbance on vegetation, hydrology and limnological conditions. When put in context with the archaeological record, it appears that the last hunter-gatherer communities were resilient at an extra-local scale, facing episodes of vulnerability due to volcanic activity, suggesting that their flexible nomadic patterns and foraging economies were an efficient source of risk management against the volcanic eruptions and their ecological impacts., (© 2023. The Author(s).)

Defined as the unpleasant sensation that causes the desire to scratch, pruritus is the most common skin symptom associated with uremia and appears in almost half of patients with advanced chronic kidney disease (CKD). Beyond its direct impact on quality of life, CKD-associated pruritus (CKD-aP) is an independent predictor of mortality that also has a synergistic effect with other quality of life-related symptoms, such as insomnia, depression, and anxiety. Although different mechanisms have been proposed to explain the origin of Pa-ERC, its etiopathogenesis is still not fully understood. Since new therapeutic targets have been identified and several clinical trials have recently shown promising results, our current understanding of the interrelationships has expanded significantly and the pathophysiological mechanisms underlying CKD-aP are now considered to be multifactorial. The potential triggers of pruritus in patients with CKD are discussed in this review, including hypotheses about skin xerosis, accumulation of uremic toxins, dysregulation of the immune system and systemic inflammation, uremic neuropathy, and imbalances in the endogenous opioid system. Other non-uremic causes of pruritus are also discussed, with the aim of guiding the physicians to apply an adequate aetiopathogenic approach to CKD-aP in their day-to-day clinical practice., (Copyright © 2022 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.)

Background: The clinical effectiveness of coronavirus disease 2019 (COVID-19) vaccination in kidney transplant (KT) recipients is lower than in the general population., Methods: From April to October 2021, 481 KT recipients with COVID-19, included in the Spanish Society of Nephrology COVID-19 Registry, were analyzed. Data regarding vaccination status and vaccine type were collected, and outcomes of unvaccinated or partially vaccinated patients (n = 130) were compared with fully vaccinated patients (n = 351)., Results: Clinical picture was similar and survival analysis showed no differences between groups: 21.7% of fully vaccinated patients and 20.8% of unvaccinated or partially vaccinated died (P = 0.776). In multivariable analysis, age and pneumonia were independent risk factors for death, whereas vaccination status was not related to mortality. These results remained similar when we excluded patients with partial vaccination, as well as when we analyzed exclusively hospitalized patients. Patients vaccinated with mRNA-1273 (n = 213) showed a significantly lower mortality than those who received the BNT162b2 vaccine (n = 121) (hazard ratio: 0.52; 95% confidence interval, 0.31-0.85; P = 0.010)., Conclusions: COVID-19 severity in KT patients has remained high and has not improved despite receiving 2 doses of the mRNA vaccine. The mRNA-1273 vaccine shows higher clinical effectiveness than BNT162b2 in KT recipients with breakthrough infections. Confirmation of these data will require further research taking into account the new variants and the administration of successive vaccine doses., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

The present study reports the evidence of a radioactive contamination in a wetland located downstream from a former French U mine in Brittany. This situation is demonstrated according to the measurements of gamma dose rates and activity ratios of 238 U and 232 Th-decay series nuclides, which give the justification regarding the accumulation of significant amounts of 238 U, 230 Th and 226 Ra in this wetland. The dose rate map highlights an increase of radiation level along the former mine water pathway compared to the background value, with a maximum value of 1500 nSv.h -1 reached in the wetland. Activities of 238 U, 230 Th and 226 Ra and 232 Th/ 238 U ratios measured in surface wetland soils are significantly higher than the geochemical background. 230 Th/ 238 U ratios less than unity suggest a preferential accumulation of U in the wetland, compared to its daughter isotopes. Moreover, the loss of 226 Ra compared to 230 Th raises its higher mobility compared to its parent isotope. In far-field sediments, 226 Ra/ 238 U ratio of 1.76 implies a different geochemical behavior of U, which could be explained by the occurrence of mobile U species. The results suggest that contamination of wetland soils and far-field sediments could result from discharges of underground mine waters., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The addition of stationary phases or sample modifiers can be used to modify the separation achievable in the diffusion domain of diffusion NMR experiments or provide information on the nature of the analyte-sample modifier interaction. Unfortunately, the addition of insoluble chromatographic stationary phases can lead to line broadening and degradation in spectral resolution, largely because of differences in magnetic susceptibility between the sample and the stationary phase. High-resolution magic angle spinning (HR-MAS) techniques can be used to remove this broadening. Here, we attempt the application of HR-MAS to size-exclusion chromatographic NMR with limited success. Observed diffusion coefficients for polymer molecular weight reference standards are shown to be larger than those obtained on static samples. Further investigation reveals that under HR-MAS it is possible to obtain reasonably accurate estimates of diffusion coefficients, using either full rotor synchronisation or sophisticated pulse sequences. The requirement for restricting the sample to the centre of the MAS rotor to ensure homogeneous magnetic and RF fields is also tested. Copyright © 2016 John Wiley & Sons, Ltd., (Copyright © 2016 John Wiley & Sons, Ltd.)

Knowledge of sedimentation rates in lakes is required to understand and quantify the geochemical processes involved in scavenging and remobilization of contaminants at the Sediment-Water Interface (SWI). The well-known 210 Pb excess ( 210 Pb ex ) method cannot be used for quantifying sedimentation rates in uranium-enriched catchments, as large amounts of 210 Pb produced by weathering and human activities may dilute the atmospheric 210 Pb. As an alternative dating method in these cases, we propose an original method based on 232 Th decay series nuclides. This study focuses on an artificial lake located in a granitic catchment downstream from a former uranium mine site. The exponential decay of 228 Ra excess ( 228 Ra ex ) with depth in two long cores yields sedimentation rates of 2.4 and 5.2 cm yr -1 respectively. These sedimentation rates lead to the attribution of the 137 Cs activity peak observed at depth to the Chernobyl fallout event of 1986. The 228 Ra ex method was also applied to two short cores which did not display the 137 Cs peak, and mean sedimentation rates of 2.1 and 4.0 cm y -1 were deduced. The proposed method may replace the classical radiochronological methods ( 210 Pb ex , 137 Cs) to determine sedimentation rates in granitic catchments., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Background: Emergency department (ED) readmissions are considered an indicator of healthcare quality that is particularly relevant in older adults. The primary objective of this study was to identify key factors for predicting patients returning to the ED within 30 days of being discharged., Methods: We analysed patients who attended our ED in June 2014, stratified into four groups based on the Kaiser pyramid. We collected data on more than 100 variables per case including demographic and clinical characteristics and drug treatments. We identified the variables with the highest discriminating power to predict ED readmission and constructed classifiers using machine learning methods to provide predictions., Results: Classifier performance distinguishing between patients who were and were not readmitted (within 30 days), in terms of average accuracy (AC). The variables with the greatest discriminating power were age, comorbidity, reasons for consultation, social factors, and drug treatments., Conclusions: It is possible to predict readmissions in stratified groups with high accuracy and to identify the most important factors influencing the event. Therefore, it will be possible to develop interventions to improve the quality of care provided to ED patients.

The use of chromatographic stationary phases or solvent modifiers to modulate diffusion properties in NMR experiments is now well established. Their use can be to improve resolution in the diffusion domain or to provide an insight into analyte-modifier interactions and, hence, the chromatography process. Here, we extend previous work using size-exclusion chromatographic stationary phases to the investigation of polymer mixtures. We demonstrate that similar diffusion modulation behaviour is observed with a size-exclusion chromatographic stationary phase that can be understood in terms of size-exclusion behaviour., (Copyright © 2014 John Wiley & Sons, Ltd.)

Introduction and Objectives: The Sociedad Española de Cardiología (Spanish Society of Cardiology) every year awards grants to finance research in the field of cardiovascular diseases. The aim of this study is to identify the impact of these investments during the period 2000-2006 from the subsequently published articles in scientific journals., Methods: Using the identifying data of each project as search terms, all articles that resulted from these grants were located in the Spanish Índice Médico Español and Índice Bibliográfico Español en Ciencias de la Salud databases, and in Science Citation Index-Expanded and Scopus. Descriptive statistical analysis of these articles included type of grant, number and amount awarded per year, and the recipient's sex and institutional affiliation., Results: The Sociedad Española de Cardiología awarded €3,270,877 to 207 recipients, an average annual total of €467,268. We identified 231 publications that resulted from 123 (59.42%) of these grants. The average number of articles per grant awarded was 1.12, and 1.9 when taking into account only the awards that led to publication., Conclusions: During the period 2000 to 2006, the Sociedad Española de Cardiología/ Fundación Española del Corazón (Spanish Heart Foundation) provided about €500,000 per year to fund research grants, thereby contributing to the fight against cardiovascular diseases. Almost 60% of grants have led to publications, 73% of which were published in international journals, and 91.34% in national or international journals with an impact factor in the Journal Citation Reports., (Copyright © 2011 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.)

Adhesion molecules appear on leukocytes and endothelial cells mediating the localization and migration of leukocytes to sites of inflammation. Rejecting kidney grafts have shown an increased expression of these molecules. Recent reports have detected in serum soluble forms of adhesion molecules that could play a role in regulating inflammation. We have measured by ELISA the circulating serum levels of ICAM-1, VCAM-1 and E-selectin in: 23 controls, 33 chronic renal failure patients (CRF), 20 hemodialysis patients (HD), 17 samples from 6 patients with stable kidney graft function (STx), 25 samples from 8 patients with steroid-responsive rejection proven by biopsy, and 28 samples from 9 patients with steroid-resistant rejection and good response to OKT3. There was not a rise in cICAM-1 or cE-selectin levels during rejection compared with the steady phase before and after rejection. In the case of cVCAM-1, only the OKT3 group showed increased rejection levels (P < 0.05) that were maintained after rejection. For ICAM-1, CRF and HD groups had higher levels than the remaining groups. cVCAM-1 levels were elevated in all groups when compared with control, furthermore, OKT3 and HD groups had higher levels than the STx, CRF, or steroid-responsive groups. For cE-selectin, we only found differences between the CRF and both rejection groups. Serum creatinine correlated significantly with c-ICAM-1 and cVCAM-1 R = 0.30 and R = 0.22), but not with cE-selectin. We conclude that soluble adhesion molecules levels are not valuable markers for rejection. Patients with chronic renal failure have increased levels of adhesion molecules, which could reflect an impaired elimination.