Nitrogen transformations and its underlying microbial communities in differently managed soils under future projected rainfall variability

Soil microbial communities play a fundamental role in maintaining a broad range of soil functions and ecosystem services. Especially nutrient provisioning to cultivated crops are of prime interest in agricultural contexts in order to maintain the production of food, fibre and fuel for the ever increasing human population. Since Nitrogen (N) is the most limiting nutrient in agroecosystem and it’s cycling and availability is highly dependent on microbial driven processes, we investigated the impact of farming systems on related ecosystem processes and herein involved soil microbial communities. Considering global climate change, also the potential to withstand rainfall variability was assessed

A Cost-Effectiveness Protocol for Flood-Mitigation Plans Based on Leeds’ Boxing Day 2015 Floods

Inspired by the Boxing Day 2015 flood of the River Aire in Leeds, UK, and subsequent attempts to mitigate adverse consequences of flooding, the goals considered are: (i) to revisit the concept of flood-excess volume (FEV) as a complementary diagnostic for classifying flood events; (ii) to establish a new roadmap/protocol for assessing flood-mitigation schemes using FEV; and, (iii) to provide a clear, graphical cost-effectiveness analysis of flood mitigation, exemplified for a hypothetical scheme partially based on actual plans. We revisit the FEV concept and present it as a three-panel graph using thresholds and errors. By re-expressing FEV as a 2m -deep square lake of equivalent capacity, one can visualise its dimensions in comparison with the river valley considered. Cost-effectiveness of flood-mitigation measures is expressed within the FEV square-lake; different scenarios of our hypothetical flood-mitigation scheme are then presented and assessed graphically, with each scenario involving a combination, near and further upstream of Leeds, of higher (than existing) flood-defence walls, enhanced flood-plain storage sites, giving-room-to-the-river bed-widening and natural flood management. Our cost-effectiveness analysis is intended as a protocol to compare and choose between flood-mitigation scenarios in a quantifiable and visual manner, thereby offering better prospects of being understood by a wide audience, including citizens and city-council planners. Using techniques of data analysis combined with general river hydraulics, common-sense and upper-bound estimation, we offer an accessible check of flood-mitigation plans

Review of the mechanisms of debris-flow impact against barriers

Our limited understanding of the mechanisms pertaining to the force exerted by debris flows on barriers makes it difficult to ascertain whether a design is inadequate, adequate, or over-designed. The main scientific challenge is because flow-type landslides impacting a rigid barrier is rarely captured in the field, and no systematic, physical experimental data is available to reveal the impact mechanisms. An important consideration in flow-structure interaction is that the impact dynamics can differ radically depending on the composition of the flow. Currently, no framework exists that can characterize the impact behavior for a wide range of flow compositions. This review paper examines recent works on debris-flow structure interactions and the limitations of commonly used approaches to estimate the impact load for the design of barriers. Key challenges faced in this area and outlook for further research are discussed

Produção animal na Região Metropolitana de Campinas.

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Compared to conventional, ecological intensive management promotes beneficial proteolytic soil microbial communities for agro-ecosystem functioning under climate change-induced rain regimes

Projected climate change and rainfall variability will affect soil microbial communities, biogeochemical cycling and agriculture. Nitrogen (N) is the most limiting nutrient in agroecosystems and its cycling and availability is highly dependent on microbial driven processes. In agroecosystems, hydrolysis of organic nitrogen (N) is an important step in controlling soil N availability. We analyzed the effect of management (ecological intensive vs. conventional intensive) on N-cycling processes and involved microbial communities under climate change-induced rain regimes. Terrestrial model ecosystems originating from agroecosystems across Europe were subjected to four different rain regimes for 263 days. Using structural equation modelling we identified direct impacts of rain regimes on N-cycling processes, whereas N-related microbial communities were more resistant. In addition to rain regimes, management indirectly affected N-cycling processes via modifications of N-related microbial community composition. Ecological intensive management promoted a beneficial N-related microbial community composition involved in N-cycling processes under climate change-induced rain regimes. Exploratory analyses identified phosphorus-associated litter properties as possible drivers for the observed management effects on N-related microbial community composition. This work provides novel insights into mechanisms controlling agro-ecosystem functioning under climate change

Prevalence of Metabolic Syndrome and Risks of Abnormal Serum Alanine Aminotransferase in Hispanics: A Population-Based Study

Study the prevalence of metabolic syndrome (MS) and risk factors for and association with elevated alanine aminotransferase (ALT) as markers of hepatic injury in a large Hispanic health disparity cohort with high rates of obesity.Analysis of data from a prospective cross-sectional population based study. From 2004-7, we randomly recruited 2000 community participants to the Cameron County Hispanic Cohort collecting extensive socioeconomic, clinical and laboratory data. We excluded 153 subjects due to critical missing data. Pearson chi-square tests and Student's t-tests were used for categorical and continuous variable analysis, respectively. Logistic regression analysis was performed to determine the risk factors for elevated ALT.The mean age of the cohort was 45 years and 67% were females. The majority of the cohort was either overweight (32.4%) or obese (50.7%). Almost half (43.7%) had MS and nearly one-third diabetes. Elevated ALT level was more prevalent in males than females. Obesity was a strong risk for abnormal ALT in both genders. Hypertriglyceridemia, hypercholesterolemia and young age were risks for elevated ALT in males only, whereas increased fasting plasma glucose was associated with elevated ALT in females only.We identified high prevalence of MS and markers of liver injury in this large Mexican American cohort with gender differences in prevalence and risk factors, with younger males at greatest risk

Structural Insights into the Quinolone Resistance Mechanism of Mycobacterium tuberculosis DNA Gyrase

Mycobacterium tuberculosis DNA gyrase, an indispensable nanomachine involved in the regulation of DNA topology, is the only type II topoisomerase present in this organism and is hence the sole target for quinolone action, a crucial drug active against multidrug-resistant tuberculosis. To understand at an atomic level the quinolone resistance mechanism, which emerges in extensively drug resistant tuberculosis, we performed combined functional, biophysical and structural studies of the two individual domains constituting the catalytic DNA gyrase reaction core, namely the Toprim and the breakage-reunion domains. This allowed us to produce a model of the catalytic reaction core in complex with DNA and a quinolone molecule, identifying original mechanistic properties of quinolone binding and clarifying the relationships between amino acid mutations and resistance phenotype of M. tuberculosis DNA gyrase. These results are compatible with our previous studies on quinolone resistance. Interestingly, the structure of the entire breakage-reunion domain revealed a new interaction, in which the Quinolone-Binding Pocket (QBP) is blocked by the N-terminal helix of a symmetry-related molecule. This interaction provides useful starting points for designing peptide based inhibitors that target DNA gyrase to prevent its binding to DNA

An Accurate Definition of the Status of Inactive Hepatitis B Virus Carrier by a Combination of Biomarkers (FibroTest-ActiTest) and Viral Load

BACKGROUND: The combination of transaminases (ALT), biopsy, HBeAg and viral load have classically defined the inactive status of carriers of chronic hepatitis B. The use of FibroTest (FT) and ActiTest (AT), biomarkers of fibrosis and necroinflammatory activity, has been previously validated as alternatives to biopsy. We compared the 4-year prognostic value of combining FT-AT and viral load for a better definition of the inactive carrier status. METHODS AND FINDINGS: 1,300 consecutive CHB patients who had been prospectively followed since 2001 were pre-included. The main endpoint was the absence of liver-related complications, transplantation or death. We used the manufacturers' definitions of normal FT (< = 0.27), normal AT (< = 0.29) and 3 standard classes for viral load. The adjustment factors were age, sex, HBeAg, ethnic origin, alcohol consumption, HIV-Delta-HCV co-infections and treatment. RESULTS: 1,074 patients with baseline FT-AT and viral load were included: 41 years old, 47% African, 27% Asian, 26% Caucasian. At 4 years follow-up, 50 complications occurred (survival without complications 93.4%), 36 deaths occurred (survival 95.0%), including 27 related to HBV (survival 96.1%). The prognostic value of FT was higher than those of viral load or ALT when compared using area under the ROC curves [0.89 (95%CI 0.84-0.93) vs 0.64 (0.55-0.71) vs 0.53 (0.46-0.60) all P<0.001], survival curves and multivariate Cox model [regression coefficient 5.2 (3.5-6.9; P<0.001) vs 0.53 (0.15-0.92; P = 0.007) vs -0.001 (-0.003-0.000;P = 0.052)] respectively. A new definition of inactive carriers was proposed with an algorithm combining "zero" scores for FT-AT (F0 and A0) and viral load classes. This new algorithm provides a 100% negative predictive value for the prediction of liver related complications or death. Among the 275 patients with the classic definition of inactive carrier, 62 (23%) had fibrosis presumed with FT, and 3 died or had complications at 4 year. CONCLUSION: In patients with chronic hepatitis B, a combination of FibroTest-ActiTest and viral load testing accurately defined the prognosis and the inactive carrier status