1,595 research outputs found

    Soil health—a new challenge for microbiologists and chemists

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    Soil health refers to the biological, chemical, and physical features of soil that are essential to long-term, sustainable agricultural productivity with minimal environmental impact. Thus, soil health provides an overall picture of soil functionality. Although it cannot be measured directly, soil health can be inferred by measuring specific soil properties (e.g. organic matter content) and by observing soil status (e.g. fertility). There is also increased interest in studying soil microorganisms in their particular environments, as microbial diversity is intimately related to soil structure and function. One of the key objectives in determining soil health is to acquire indicators that can be used to evaluate the soil’s current status and hence to develop sustainable agricultural systems. In this regard, significant progress has been made over the last few years in the development of specific biomarkers and macromolecular probes, enabling rapid and reliable measurements of soil microbial communities. In addition, modern molecular biological techniques, such as fluorescence in situ hybridization (FISH), reverse transcriptase polymerase chain reaction (RT-PCR), denaturing gradient gel electrophoresis (DGGE), and terminal restriction fragment length polymorphism (T-RFLP), have facilitated the analysis of microbial biodiversity and activity, whereas the application of modern analytical techniques, such as nuclear magnetic resonance (NMR) and pyrolysisgas chromatography-mass spectrometry (Py-GC-MS), have provided data on soil chemistry. The combination of these two approaches offers promise in determining soil health status. [Int Microbiol 2005; 8(1):13-21

    Pyrolysis-compound-specific hydrogen isotope analysis (δ2H Py-CSIA) of Mediterranean olive oils

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    The analysis of the hydrogen stable isotope composition (δ2H) of organic compounds provides information about its geographical origin. In this work, δ2H composition of specific compounds released by direct analytical pyrolysis (Py-CSIA) of extra virgin olive oils EVOOs was studied avoiding the use of any chemical and/or physical treatments, derivatization or previous separation steps. A collection of EVOOs from Mediterranean countries (Portugal, Spain, France, Tunisia and Turkey) was used for authentication of the olive oil samples. The δ2H value for 9 pyrolysis compounds present in all EVOOs, ranged between −112 and −267 mUr. These compounds were selected as possible surrogate descriptors linked to the olive oil geographic origin. Principal Component Analysis showed that δ2H was highly correlated with geographical longitude and annual temperature. Multiple Linear Regression analysis revealed that δ2H value of pyrolysis compounds can significantly (P < 0.05) predicts longitude, mean annual temperature and distance to the sea. The results suggest that the methodology used has a high potential to assess EVOOs geographic origin. This is the first report that evaluates δ2H directly from the pyrolysis products of olive oil using Py-CSIA. The approach used represents an innovative, fast, reproducible and reliable authentication technique

    Extracción Automática de la Línea Central de Estructuras Tubulares: Implementación Matricial

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    Se propone una nueva implementación matricial de un algoritmo para la extracción automática de la línea central de estructuras tubulares. El algoritmo seleccionado calcula la línea central de estructuras complejas sin la necesidad de interacción con el usuario. En el trabajo se explica detalladamente cómo llevar a cabo la implementación matricial utilizando el lenguaje de computación de Matlab. La implementación matricial permite el cálculo de la línea central en pocos segundos, mejorando en varios grados de magnitud la implementación disponible en ITK

    Organic carbon and environmental quality of riverine and off-shore sediments from the Gulf of Cádiz, Spain

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    6 páginas, 2 figuras, 3 tablas, 14 referencias.-- [email protected] we show that heavy metal geoaccumulation is apparent in the Tinto and Odiel estuary and, at a lower magnitude, in off-shore sediments. Values above probable effects level (PEL) are recorded for As, Cu, Hg, Pb and Zn in the Tinto and Odiel estuary, for As and Hg in the associated off-shore sediments and for As in the Guadiana River. Significant correlations were found between total organic carbon (TOC) and Cr, Cu, Ni and Zn in the Tinto and Odiel estuary, and Cr, Cu, Ni, Pb, Hg and As in the Guadiana River. PCA analysis differentiated the three studied locations.Peer reviewe

    Organic carbon and environmental quality of riverine and off-shore sediments from the Gulf of Cádiz, Spain

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    6 páginas, 2 figuras, 3 tablas, 14 referencias.-- [email protected] we show that heavy metal geoaccumulation is apparent in the Tinto and Odiel estuary and, at a lower magnitude, in off-shore sediments. Values above probable effects level (PEL) are recorded for As, Cu, Hg, Pb and Zn in the Tinto and Odiel estuary, for As and Hg in the associated off-shore sediments and for As in the Guadiana River. Significant correlations were found between total organic carbon (TOC) and Cr, Cu, Ni and Zn in the Tinto and Odiel estuary, and Cr, Cu, Ni, Pb, Hg and As in the Guadiana River. PCA analysis differentiated the three studied locations.Peer reviewe

    Organic matter sources for tidal marsh sediment over the past two millennia in the Minho River estuary (NW Iberian Peninsula)

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    Environmental changes during the last 2 millennia in the Minho River tidal marsh (NW Portugal-Spain border) were reconstructed. Changes in the sources of organic matter (OM) delivered to the marsh were evaluated from elemental, isotopic and molecular composition using a 1 m sediment core. Carbon isotopic composition (delta13C) and organic carbon to total nitrogen ratio (Corg/N) provided valuable information concerning the origin of the OM. These parameters indicated a major input from land plants, reaching a maximum at 1100–1200 and 1750–1850 AD. These periods match with major flood events in the NW of the Iberian Peninsula, as reported by several authors. A significant reduction in the terrestrial signature occurred at 6–4 cm (ca. 1960–1985 AD), which is contemporaneous with the construction of several major dams on the Minho River. The distribution of selected lipid biomarkers, including n-alkanes, n-fatty acids and n-alkan-2-ones and specific parameters derived from the molecular distributions, were useful for refining bulk geochemical results. Long chain n- alkanes with an odd number of carbons are indicators of soil-and vascular plant derived terrestrial OM and were dominant throughout the core. In addition, a greater contribution of plankton-derived lipids was observed in the sections corresponding to ca. 1960–1985 AD (6–4 cm) and ca. 100–200 AD (96–94 cm). Although different degradation rates for individual compounds might have partly affected biomarker assemblages, the variations could be attributed to a sharp decrease in the freshwater contribution to the Minho River Estuary (dam construction) and a possible marine highstand, respectively. In addition, several parameters suggested changes in land use (including deforestation and farming) and probably the effects of mining exploitation during the Roman occupation of the area.We acknowledge the funding by the Foundation for Science and Technology (FCT) of Portugal for J.M. M’s PhD. Grant (SFRH/BD/45528/2008) and for the WestLog Project (PTDC/CTE-GIX/105370/2008). E.L. was awarded a Ralph E. Powe Junior Faculty Enhancement Award. This is a contribution to the IGCP Project 588 and to the Geo-Q Research Unit (Aranzadi).Peer reviewe

    Cost‐effectiveness and cost‐utility evaluation of individual vs. group transdiagnostic psychological treatment for emotional disorders in primary care (PsicAP‐Costs): a multicentre randomized controlled trial protocol

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    Background: Emotional disorders are common, and they have become more prevalent since the COVID‐19 pan‐ demic. Due to a high attendance burden at the specialized level, most emotional disorders in Spain are treated in primary care, where they are usually misdiagnosed and treated using psychotropic drugs. This contributes to perpetu‐ ate their illness and increase health care costs. Following the IAPT programme and the transdiagnostic approach, the PsicAP project developed a brief group transdiagnostic cognitive‐behavioural therapy (tCBT) as a cost‐effective alternative. However, it is not suitable for everyone; in some cases, one‐on‐one sessions may be more effective. The objective of the present study is to compare, in cost‐benefit terms, group and individual tCBT with the treatment usu‐ ally administered in Spanish primary care (TAU). Methods: A randomized, controlled, multicentre, and single‐blinded trial will be performed. Adults with mild to moderate emotional disorders will be recruited and placed in one of three arms: group tCBT, individual tCBT, or TAU. Medical data and outcomes regarding emotional symptoms, disability, quality of life, and emotion regulation biases will be collected at baseline, immediately after treatment, and 6 and 12 months later. The data will be used to calcu‐ late incremental cost‐effectiveness and cost‐utility ratios. Discussion: This trial aims to contribute to clinical practice research. The involvement of psychologists in primary care and the implementation of a stepped‐care model for mental disorders are recommended. Group therapy and a transdiagnostic approach may help optimize health system resources and unblock waiting lists so that people can spend less time experiencing mental health problems. Trial registration: ClinicalTrials.gov: NCT04847310; Protocols.io: bx2npqde. (April 19, 2021

    Motion of CMS detector and mechanical structures during Magnet Cycles and Stability Periods from 2008 to 2013 as observed by the Link Alignment System

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    Magnet Cycles and Stability Periods of the CMS Experiment are studied with the Alignment Link System data recorded along the 2008-2013 years of operation. The motions of the mechanical structures due to the magnetic field forces are studied and the mechanical stability of the detector during the physics data taking periods is verified.Peer Reviewe

    Fire effects on C and H isotopic composition in plant biomass and soil: Bulk and particle size fractions

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    This work studies carbon (C) and hydrogen (H) isotope composition of plant biomass and soil organic matter (SOM) in an attempt to assess both, changes exerted by fire and possible inputs of charred materials to the soil after a wildfire. Isotope composition of bulk soil, soil particle size fractions and biomass of the dominant standing vegetation in the area (Quercus suber) from Doñana National Park (SW-Spain) were studied by isotope ratio mass spectrometry (IRMS). SOM C isotope composition indicates the occurrence of two SOM pools with different degree of alteration. Coarse soil fractions (>0.5 mm) were found 13C depleted with δ13C values close to those in leaf biomass, pointing to a predominance of poorly transformed SOM. Conversely, fine fractions (0.5 mm) displayed significant lower δ2H values than the intermediate and fine ones (<0.5 mm), again similar to those in leaf biomass (c. -80‰), whereas the fine fractions were found deuterium (2H)-enriched with significant higher δ2H values (c. 50‰), suggesting physical speciation of H depending on soil particle size. The fire produced a significant 2H depletion (Δ2H c. -10‰) in the finer fractions (<0.1 mm). The study of stable isotope analysis added new information and complements the results obtained by other proxies to better understand the effect of fire on SO

    Commissioning and performance of the CMS silicon strip tracker with cosmic ray muons

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    46 páginas, 17 figuras, 8 tablas.-- Open Access.-- CMS Collaboration: et al.During autumn 2008, the Silicon Strip Tracker was operated with the full CMS experiment in a comprehensive test, in the presence of the 3.8 T magnetic field produced by the CMS superconducting solenoid. Cosmic ray muons were detected in the muon chambers and used to trigger the readout of all CMS sub-detectors. About 15 million events with a muon in the tracker were collected. The efficiency of hit and track reconstruction were measured to be higher than 99% and consistent with expectations from Monte Carlo simulation. This article details the commissioning and performance of the Silicon Strip Tracker with cosmic ray muons.Individuals have received support from the Marie-Curie IEF program (European Union); the Leventis Foundation; the A. P. Sloan Foundation; and the Alexander von Humboldt Foundation.Peer reviewe
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