493 research outputs found

    Grazing impact on soil chemical and biological properties under different plant cover types in a mountain area of Southern Italy.

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    Grazing can contribute to soil degradation by compaction due to roaming of livestock and loss of herbaceous cover, affecting also soil microbial community. Aim of this study was to assess grazing impact on soil microbial community and nutrient status under different plant cover types (i.e., fernery, chestnut wood, garigue). Grazed and ungrazed soils were analysed for water holding capacity, pH, organic carbon, N, S, K, Mg, Fe, Mn, Zn and Cu content, microbial biomass, fungal mycelium and potential respiration. Moreover, some ecophysiological indices, as microbial quotient, coefficient of endogenous mineralization (CEM), metabolic quotient (qCO2) and fungal fraction of microbial carbon were calculated. The results of present study showed that a moderate intensity grazing had low or no impact on chemical characteristics of soils and affects microbial community mainly in grazed areas with lower vegetation cover and lower content of nutrient and organic carbon, compared to areas with a thick layer of vegetation

    An alternative SNR-based weighted-LSM algorithm to classify and measure the concentration of Biological Agents from Laser-Induced Fluorescence

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    Optical spectroscopic techniques, such as Laser-Induced Breakdown Spectroscopy (LIBS) or Laser-Induced Fluorescence (LIF), have already been used to study and detect Biological Agents (BAs). Unfortunately, BAs usually share similar-shaped emitted spectra and low-signal intensities, making their detection and classification difficult to assess. Least-Square Minimisation (LSM) based algorithms are usually deployed to measure the concentration of agents from spectra. Recently, it has been shown how the use of ad hoc weights can help in improving the performance of the concentration evaluation. More specifically, it has been observed that the “weight matrix” should be modelled as a function of the boundary conditions of the problem. This work proposes a new weight matrix that is based on the Signal-to-Noise Ratio (SNR) of the measurements. The idea is based on the fact that more noisy data are less reliable and therefore weight should be lowered. The paper, after a brief introduction and review of the LSM applied to spectra, will show the new methodology. A systematic analysis of the new algorithm is done and the comparison with the other LSM algorithms is presented. The results clearly show that there is a range of parameters for which the new algorithm performs better

    Atomic and molecular data for spacecraft re-entry plasmas

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    The modeling of atmospheric gas, interacting with the space vehicles in re-entry conditions in planetary exploration missions, requires a large set of scattering data for all those elementary processes occurring in the system. A fundamental aspect of re-entry problems is represented by the strong non-equilibrium conditions met in the atmospheric plasma close to the surface of the thermal shield, where numerous interconnected relaxation processes determine the evolution of the gaseous system towards equilibrium conditions. A central role is played by the vibrational exchanges of energy, so that collisional processes involving vibrationally excited molecules assume a particular importance. In the present paper, theoretical calculations of complete sets of vibrationally state-resolved cross sections and rate coefficients are reviewed, focusing on the relevant classes of collisional processes: resonant and non-resonant electron-impact excitation of molecules, atom-diatom and molecule-molecule collisions as well as gas-surface interaction. In particular, collisional processes involving atomic and molecular species, relevant to Earth (N2, O2, NO), Mars (CO2, CO, N2) and Jupiter (H2, He) atmospheres are considered

    Critical range of soil organic carbon in southern Europe lands under desertification risk

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    Soil quality is fundamental for ecosystem long term functionality, productivity and resilience to current climatic changes. Despite its importance, soil is lost and degraded at dramatic rates worldwide. In Europe, the Mediterranean areas are a hotspot for soil erosion and land degradation due to a combination of climatic conditions, soils, geomorphology and anthropic pressure. Soil organic carbon (SOC) is considered a key indicator of soil quality as it relates to other fundamental soil functions supporting crucial ecosystem services. In the present study, the functional relationships among SOC and other important soil properties were investigated in the topsoil of 38 sites under different land cover and management, distributed over three Mediterranean regions under strong desertification risk, with the final aim to define critical SOC ranges for fast loss of important soil functionalities. The study sites belonged to private and public landowners seeking to adopt sustainable land management practices to support ecosystem sustainability and productivity of their land. Data showed a very clear relationship between SOC concentrations and the other analyzed soil properties: total nitrogen, bulk density, cation exchange capacity, available water capacity, microbial biomass, C fractions associated to particulate organic matter and to the mineral soil component and indirectly with net N mineralization. Below 20 g SOC kg−1, additional changes of SOC concentrations resulted in a steep variation of all the analyzed soil indicators, an order of magnitude higher than the changes occurring between 50 and 100 g SOC kg−1 and 3–4 times the changes observed at 20–50 g SOC kg−1. About half of the study sites showed average SOC concentration of the topsoil centimetres <20 g SOC kg−1. For these areas the level of SOC might hence be considered critical and immediate and effective recovery management plans are needed to avoid complete land degradation in the next future

    Atomic and molecular data for spacecraft re-entry plasmas

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    The modeling of atmospheric gas, interacting with the space vehicles in re-entry conditions in planetary exploration missions, requires a large set of scattering data for all those elementary processes occurring in the system. A fundamental aspect of re-entry problems is represented by the strong non-equilibrium conditions met in the atmospheric plasma close to the surface of the thermal shield, where numerous interconnected relaxation processes determine the evolution of the gaseous system towards equilibrium conditions. A central role is played by the vibrational exchanges of energy, so that collisional processes involving vibrationally excited molecules assume a particular importance. In the present paper, theoretical calculations of complete sets of vibrationally state-resolved cross sections and rate coefficients are reviewed, focusing on the relevant classes of collisional processes: resonant and non-resonant electron-impact excitation of molecules, atom-diatom and molecule-molecule collisions as well as gas-surface interaction. In particular, collisional processes involving atomic and molecular species, relevant to Earth (N-2, O-2, NO), Mars (CO2, CO, N-2) and Jupiter (H-2, He) atmospheres are considered

    Metabolomic Approaches for Detection and Identification of Biomarkers and Altered Pathways in Bladder Cancer

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    Metabolomic analysis has proven to be a useful tool in biomarker discovery and the molecular classification of cancers. In order to find new biomarkers, and to better understand its pathological behavior, bladder cancer also has been studied using a metabolomics approach. In this article, we review the literature on metabolomic studies of bladder cancer, focusing on the different available samples (urine, blood, tissue samples) used to perform the studies and their relative findings. Moreover, the multi-omic approach in bladder cancer research has found novel insights into its metabolic behavior, providing excellent start-points for new diagnostic and therapeutic strategies. Metabolomics data analysis can lead to the discovery of a “signature pathway” associated with the progression of bladder cancer; this aspect could be potentially valuable in predictions of clinical outcomes and the introduction of new treatments. However, further studies are needed to give stronger evidence and to make these tools feasible for use in clinical practice

    Evaluation of air contamination in orthopaedic operating theatres in hospitals in Southern Italy: The IMPACT project

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    Postoperative infections are a concern, especially in total knee and total hip arthroplasty. We evaluated the air quality in orthopaedic operating theatres in southeastern Italy to determine the level of bacterial contamination as a risk factor for postoperative infection. Thirty-five hospitals with operating theatres focused on total knee and total hip arthroplasty participated. We sampled the air passively and actively before surgeries began for the day (at rest) and 15 min after the surgical incision (in operation). We evaluated bacterial counts, particle size, mixed vs turbulent airflow systems, the number of doors, number of door openings during procedures and number of people in the operating theatre. We found no bacterial contamination at rest for all sampling methods, and significantly different contamination levels at rest vs in operation. We found no association between the number of people in the surgical team and bacteria counts for both mixed and turbulent airflow systems, and low bacterial loads, even when doors were always open. Overall, the air quality sampling method and type of ventilation system did not affect air quality

    Diagnostic Targeted Resequencing in 349 Patients with Drug-Resistant Pediatric Epilepsies Identifies Causative Mutations in 30 Different Genes

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    Targeted resequencing gene panels are used in the diagnostic setting to identify gene defects in epilepsy. We performed targeted resequencing using a 30-genes panel and a 95-genes panel in 349 patients with drug-resistant epilepsies beginning in the first years of life. We identified 71 pathogenic variants, 42 of which novel, in 30 genes, corresponding to 20.3% of the probands. In 66% of mutation positive patients, epilepsy onset occurred before the age of 6 months. The 95-genes panel allowed a genetic diagnosis in 22 (6.3%) patients that would have otherwise been missed using the 30-gene panel. About 50% of mutations were identified in genes coding for sodium and potassium channel components. SCN2A was the most frequently mutated gene followed by SCN1A, KCNQ2, STXBP1, SCN8A, CDKL5, and MECP2. Twenty-nine mutations were identified in 23 additional genes, most of them recently associated with epilepsy. Our data show that panels targeting about 100 genes represent the best cost-effective diagnostic option in pediatric drug-resistant epilepsies. They enable molecular diagnosis of atypical phenotypes, allowing to broaden phenotype-genotype correlations. Molecular diagnosis might influence patients' management and translate into better and specific treatment recommendations in some conditions

    Validation of the Italian version of the Non-Communicating Children's Pain Checklist-Postoperative Version

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    BACKGROUND: This study evaluated the validity and reliability of the Italian version of the Non-Communicating Children's Pain Checklist-Postoperative version (I-NCCPC-PV). METHODS: The original NCCPC-PV version was translated into Italian following the guidelines for "the translation, adaptation, and validation of instruments or scales for cross-cultural healthcare research". We tested the Italian NCCPC-PV version (I-NCCPC-PV) in 40 children (3-18 years of age) with severe to profound Intellectual Disability and no verbal communication. Each child's behavior was observed by a parent or caregiver and by an external observer in a quiet situation and a painful one. They independently assessed the child's level of pain using the translated Italian version of the NCCPCPV (I-NCCPC-PV). RESULTS: The results from 80 assessments showed that children's behavioral signs differed significantly between painful and calm situations (p < 0.001). The inter-rater reliability was poor in a quiet condition (ICC 0.62) and fair in a painful situation (ICC 0.77). The inter-rater agreement was good in both calm and painful conditions (72.50% and 77.50% respectively). CONCLUSION: The Italian version of the NCCPC-PV (I-NCCPC-PV) can be used for pain assessment in children with Intellectual Disability who lack verbal communication
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