617 research outputs found

    EL CULTIVO DE LA PITAYA DE AGOSTO (Stenocereus stellatus Pfeiffer) EN LA MONTAÑA DE GUERRERO

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    Objective: To characterize the cultivation of the August pitaya (Stenocereus stellatus Pfeiffer) in two communities of the Mountain of Guerrero, Mexico.Design/methodology/approach: A questionnaire was applied to a sample of 29 producers out of a total of 105 Rural Production Units (UPR), with variables on management practices of the August pitaya and its contribution in the income of rural families. The information was analyzed with descriptive statistics.Results: In the study communities, the cultivation of August pitaya is carried out by producers over 40 years old, both men and women, with an average experience of 9.8 years in crop production and few management practices. The harvest period is on average 66 days, with an estimated production of 3375.9 kg per unit of production and an average price of 7.48MXperkg.Anincomeof7.48 MX per kg. An income of 25,000 MX per year per unit of production and a total regional income of 3,044,435.07MXwasestimated.Limitationsofthestudy/Implications:ThewiderangeoftheharvestperiodandthecharacteristicthattheAugustpitayaisahighlyperishablefoodmakesitdifficulttoquantifytheproductioninahighsampleofproductionunits.Findings/Conclusions:TheAugustpitayaisalowinvestmentcropintheGuerreroMountainregion,bothineconomicandhumanresources.However,itisacropthatcontributessignificantly,especiallyseasonally,totheeconomicincomeoffamiliesintheregion.Objetivo:Caracterizarelcultivodelapitayadeagosto(StenocereusstellatusPfeiffer)endoscomunidadesdelaMontan~adeGuerrero,Meˊxico.Disen~o/metodologıˊa/aproximacioˊn:Seaplicoˊuncuestionarioconvariablessobrepraˊcticasdemanejodelapitayadeagostoydesucontribucioˊnenlosingresosdelasfamiliasruralesaunamuestrade29productoresdeuntotalde105UnidadesdeProduccioˊnRural(UPR).Lainformacioˊnseanalizoˊconestadıˊsticasdescriptivas.Resultados:Enlascomunidadesdeestudioelcultivodelapitayadeagostoesrealizadaporproductoresmayoresde40an~os,tantohombrescomomujeres,conunaexperienciapromediode9.8an~osenlaproduccioˊndelcultivoyrealizanpocaspraˊcticasdemanejo.Elperiododecosechaesenpromediode66dıˊas,conunaproduccioˊnestimadade3375.9kgporunidaddeproduccioˊnyunpreciopromediode7.48MXporkg.Seestimoˊuningresode 3,044,435.07 MX was estimated.Limitations of the study/Implications: The wide range of the harvest period and the characteristic that the August pitaya is a highly perishable food makes it difficult to quantify the production in a high sample of production units.Findings/Conclusions: The August pitaya is a low investment crop in the Guerrero Mountain region, both in economic and human resources. However, it is a crop that contributes significantly, especially seasonally, to the economic income of families in the region.Objetivo: Caracterizar el cultivo de la pitaya de agosto (Stenocereus stellatus Pfeiffer) en dos comunidades de la Montaña de Guerrero, México.Diseño/metodología/aproximación: Se aplicó un cuestionario con variables sobre prácticas de manejode la pitaya de agosto y de su contribución en los ingresos de las familias rurales a una muestra de 29 productores de un total de 105 Unidades de Producción Rural (UPR). La información se analizó conestadísticas descriptivas. Resultados: En las comunidades de estudio el cultivo de la pitaya de agosto es realizada por productores mayores de 40 años, tanto hombres como mujeres, con una experiencia promedio de 9.8 años en la producción del cultivo y realizan pocas prácticas de manejo. El periodo de cosecha es en promedio de 66 días, con una producción estimada de 3375.9 kg por unidad de producción y un precio promediode 7.48 MX por kg. Se estimó un ingreso de 25000.00 MX por año por unidad de producción y un ingreso regional total de $3,044,435.07 MX.Limitaciones del estudio/Implicaciones: El amplio rango del periodo de cosecha y la característica de que la pitaya de agosto es un cultivo altamente perecedero dificulta la cuantificación de cosecha en unamuestra alta de unidades de producción.Hallazgos/conclusiones: Al cultivo de la pitaya de agosto se le invierte poco en la región de la Montaña de Guerrero, tanto en recursos económicos como humanos. Sin embargo, es un cultivo que contribuye, sobre todo estacionalmente, de manera importante en el ingreso económico de las familias de la región

    Large-scale temperature response to external forcing in simulations and reconstructions of the last millennium

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    Understanding natural climate variability and its driving factors is crucial to assessing future climate change. Therefore, comparing proxy-based climate reconstructions with forcing factors as well as comparing these with paleo-climate model simulations is key to gaining insights into the relative roles of internal versus forced variability. A review of the state of modelling of the climate of the last millennium prior to the CMIP5-PMIP3 (Coupled Model Intercomparison Project Phase 5-Paleoclimate Modelling Intercomparison Project Phase 3) coordinated effort is presented and compared to the available temperature reconstructions. Simulations and reconstructions broadly agree on reproducing the major temperature changes and suggest an overall linear response to external forcing on multidecadal or longer timescales. Internal variability is found to have an important influence at hemispheric and global scales. The spatial distribution of simulated temperature changes during the transition from the Medieval Climate Anomaly to the Little Ice Age disagrees with that found in the reconstructions. Thus, either internal variability is a possible major player in shaping temperature changes through the millennium or the model simulations have problems realistically representing the response pattern to external forcing. A last millennium transient climate response (LMTCR) is defined to provide a quantitative framework for analysing the consistency between simulated and reconstructed climate. Beyond an overall agreement between simulated and reconstructed LMTCR ranges, this analysis is able to single out specific discrepancies between some reconstructions and the ensemble of simulations. The disagreement is found in the cases where the reconstructions show reduced covariability with external forcings or when they present high rates of temperature change

    Inter-species differences in polychlorinated biphenyls patterns from five sympatric species of odontocetes : Can PCBs be used as tracers of feeding ecology?

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    The authors gratefully acknowledge the assistance of volunteers from the Galician (CEMMA) and Portuguese (SPVS) stranding networks. The authors would like to thank R. Gallois and C. Trichet for their participation on total lipid content analysis. P. Méndez-Fernandez was supported during the research period through a PhD grant from the Fundação do Ministério de Ciência e Tecnologia de Portugal and ANIMATE project (SFRH/BD/36766/2007) and through a Science Without Borders (CSF) young talent postdoctoral grant of the Brazilian government. G. J. Pierce acknowledges support from the EU ANIMATE project (MEXC-CT-2006-042337), University of Aveiro and Caixa Geral de Depósitos (Portugal).Peer reviewedPostprin

    Emergent global patterns of ecosystem structure and function from a mechanistic general ecosystem model

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    Anthropogenic activities are causing widespread degradation of ecosystems worldwide, threatening the ecosystem services upon which all human life depends. Improved understanding of this degradation is urgently needed to improve avoidance and mitigation measures. One tool to assist these efforts is predictive models of ecosystem structure and function that are mechanistic: based on fundamental ecological principles. Here we present the first mechanistic General Ecosystem Model (GEM) of ecosystem structure and function that is both global and applies in all terrestrial and marine environments. Functional forms and parameter values were derived from the theoretical and empirical literature where possible. Simulations of the fate of all organisms with body masses between 10 µg and 150,000 kg (a range of 14 orders of magnitude) across the globe led to emergent properties at individual (e.g., growth rate), community (e.g., biomass turnover rates), ecosystem (e.g., trophic pyramids), and macroecological scales (e.g., global patterns of trophic structure) that are in general agreement with current data and theory. These properties emerged from our encoding of the biology of, and interactions among, individual organisms without any direct constraints on the properties themselves. Our results indicate that ecologists have gathered sufficient information to begin to build realistic, global, and mechanistic models of ecosystems, capable of predicting a diverse range of ecosystem properties and their response to human pressures

    Evolution of Disease Response Genes in Loblolly Pine: Insights from Candidate Genes

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    BACKGROUND: Host-pathogen interactions that may lead to a competitive co-evolution of virulence and resistance mechanisms present an attractive system to study molecular evolution because strong, recent (or even current) selective pressure is expected at many genomic loci. However, it is unclear whether these selective forces would act to preserve existing diversity, promote novel diversity, or reduce linked neutral diversity during rapid fixation of advantageous alleles. In plants, the lack of adaptive immunity places a larger burden on genetic diversity to ensure survival of plant populations. This burden is even greater if the generation time of the plant is much longer than the generation time of the pathogen. METHODOLOGY/PRINCIPAL FINDINGS: Here, we present nucleotide polymorphism and substitution data for 41 candidate genes from the long-lived forest tree loblolly pine, selected primarily for their prospective influences on host-pathogen interactions. This dataset is analyzed together with 15 drought-tolerance and 13 wood-quality genes from previous studies. A wide range of neutrality tests were performed and tested against expectations from realistic demographic models. CONCLUSIONS/SIGNIFICANCE: Collectively, our analyses found that axr (auxin response factor), caf1 (chromatin assembly factor) and gatabp1 (gata binding protein 1) candidate genes carry patterns consistent with directional selection and erd3 (early response to drought 3) displays patterns suggestive of a selective sweep, both of which are consistent with the arm-race model of disease response evolution. Furthermore, we have identified patterns consistent with diversifying selection at erf1-like (ethylene responsive factor 1), ccoaoemt (caffeoyl-CoA-O-methyltransferase), cyp450-like (cytochrome p450-like) and pr4.3 (pathogen response 4.3), expected under the trench-warfare evolution model. Finally, a drought-tolerance candidate related to the plant cell wall, lp5, displayed patterns consistent with balancing selection. In conclusion, both arms-race and trench-warfare models seem compatible with patterns of polymorphism found in different disease-response candidate genes, indicating a mixed strategy of disease tolerance evolution for loblolly pine, a major tree crop in southeastern United States

    Distribution and status of living colonies of Acropora spp. in the reef crests of a protected marine area of the Caribbean (Jardines de la Reina National Park, Cuba)

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    The reef crests of the Jardines de la Reina National Park (JRNP) are largely formed by Acropora palmata, but colonies of A. cervicornis and the hybrid A. prolifera are also present. This study shows spatial distribution of colonies, thickets and live fragments of these species in the fore reefs. Snorkeling was used to perform the direct observations. The maximum diameter of 4,399 colonies of A. palmata was measured and the health of 3,546 colonies was evaluated. The same was done to 168 colonies of A. cervicornis and 104 colonies of A. prolifera. The influence of the location and marine currents on a number of living colonies of A. palmata was analyzed. For such purpose, reef crests were divided into segments of 500 m. The marine park was divided into two sectors: East and West. The Caballones Channel was used as the reference dividing line. The park was also divided into five reserve zones. We counted 7,276 live colonies of Acropora spp. 1.4% was A. prolifera, 3.5% A. cervicornis and 95.1% A. palmata. There were 104 thickets of A. palmata, ranging from eight to 12 colonies, and 3,495 fragments; 0.6% was A. cervicornis and the rest A. palmata (99.4%). In the East sector, 263 colonies (3.8% of the total), six thickets (5.8%) and 32 fragments (1%) of A. palmate were recorded. In the same sector, there were 11 fragments (50%) of A.cervicornis and two (2%) colonies of A. prolifera. Health of A. palmata was evaluated as good and not so good in the study area. Health of A. cervicornis was critical and health of A. prolifera was good in all five reserve zones. There was a significant increase in the number of colonies from east to west (Χ2 = 11.5, gl = 3.0, p = 0.009). This corroborates the existence of an important abundance differences between the eastern and the western region of the JRNP. A negative relationship was observed between the number of colonies and the distance from the channel (Χ2 = 65.0, df = 3.0, p < 0.001). The influence of the channel, for the live colonies of A. palmata is greater within the first 2,000 m. It then decreases until approximately 6,000 m, and no significant increase beyond. The orientation of the reef crests significantly influenced the abundance of the colonies (Χ2 = 15.5, df = 2.9, p = 0.001). The results presented here provide a baseline for future research on the status of the populations of Acropora spp., considering that there has been a certain recovery of the species A. palmata during the last 10–16 years. Given the current status of the populations of Acropora spp., conservation actions focusing A. cervicornis should be prioritized

    Additional value of screening for minor genes and copy number variants in hypertrophic cardiomyopathy

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    Introduction: Hypertrophic cardiomyopathy (HCM) is the most prevalent inherited heart disease. Next-generation sequencing (NGS) is the preferred genetic test, but the diagnostic value of screening for minor and candidate genes, and the role of copy number variants (CNVs) deserves further evaluation. Methods: Three hundred and eighty-seven consecutive unrelated patients with HCM were screened for genetic variants in the 5 most frequent genes (MYBPC3, MYH7, TNNT2, TNNI3 and TPM1) using Sanger sequencing (N = 84) or NGS (N = 303). In the NGS cohort we analyzed 20 additional minor or candidate genes, and applied a proprietary bioinformatics algorithm for detecting CNVs. Additionally, the rate and classification of TTN variants in HCM were compared with 427 patients without structural heart disease. Results: The percentage of patients with pathogenic/likely pathogenic (P/LP) variants in the main genes was 33.3%, without significant differences between the Sanger sequencing and NGS cohorts. The screening for 20 additional genes revealed LP variants in ACTC1, MYL2, MYL3, TNNC1, GLA and PRKAG2 in 12 patients. This approach resulted in more inconclusive tests (36.0% vs. 9.6%, p<0.001), mostly due to variants of unknown significance (VUS) in TTN. The detection rate of rare variants in TTN was not significantly different to that found in the group of patients without structural heart disease. In the NGS cohort, 4 patients (1.3%) had pathogenic CNVs: 2 deletions in MYBPC3 and 2 deletions involving the complete coding region of PLN. Conclusions: A small percentage of HCM cases without point mutations in the 5 main genes are explained by P/LP variants in minor or candidate genes and CNVs. Screening for variants in TTN in HCM patients drastically increases the number of inconclusive tests, and shows a rate of VUS that is similar to patients without structural heart disease, suggesting that this gene should not be analyzed for clinical purposes in HCM

    Posaconazole MIC Distributions for Aspergillus fumigatus Species Complex by Four Methods: Impact of cyp51A Mutations on Estimation of Epidemiological Cutoff Values

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    ABSTRACT Estimating epidemiological cutoff endpoints (ECVs/ECOFFS) may be hindered by the overlap of MICs for mutant and nonmutant strains (strains harboring or not harboring mutations, respectively). Posaconazole MIC distributions for the Aspergillus fumigatus species complex were collected from 26 laboratories (in Australia, Canada, Europe, India, South and North America, and Taiwan) and published studies. Distributions that fulfilled CLSI criteria were pooled and ECVs were estimated. The sensitivity of three ECV analytical techniques (the ECOFFinder, normalized resistance interpretation [NRI], derivatization methods) to the inclusion of MICs for mutants was examined for three susceptibility testing methods (the CLSI, EUCAST, and Etest methods). The totals of posaconazole MICs for nonmutant isolates (isolates with no known cyp51A mutations) and mutant A. fumigatus isolates were as follows: by the CLSI method, 2,223 and 274, respectively; by the EUCAST method, 556 and 52, respectively; and by Etest, 1,365 and 29, respectively. MICs for 381 isolates with unknown mutational status were also evaluated with the Sensititre YeastOne system (SYO). We observed an overlap in posaconazole MICs among nonmutants and cyp51A mutants. At the commonly chosen percentage of the modeled wild-type population (97.5%), almost all ECVs remained the same when the MICs for nonmutant and mutant distributions were merged: ECOFFinder ECVs, 0.5 μg/ml for the CLSI method and 0.25 μg/ml for the EUCAST method and Etest; NRI ECVs, 0.5 μg/ml for all three methods. However, the ECOFFinder ECV for 95% of the nonmutant population by the CLSI method was 0.25 μg/ml. The tentative ECOFFinder ECV with SYO was 0.06 μg/ml (data from 3/8 laboratories). Derivatization ECVs with or without mutant inclusion were either 0.25 μg/ml (CLSI, EUCAST, Etest) or 0.06 μg/ml (SYO). It appears that ECV analytical techniques may not be vulnerable to overlap between presumptive wild-type isolates and cyp51A mutants when up to 11.6% of the estimated wild-type population includes mutants. KEYWORDS Aspergillus fumigatus, CLSI ECVs, ECVs, EUCAST ECVs, Etest, SYO, cyp51A mutants, posaconazole, triazole resistance, wild typ

    Charge separation relative to the reaction plane in Pb-Pb collisions at sNN=2.76\sqrt{s_{\rm NN}}= 2.76 TeV

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    Measurements of charge dependent azimuthal correlations with the ALICE detector at the LHC are reported for Pb-Pb collisions at sNN=2.76\sqrt{s_{\rm NN}} = 2.76 TeV. Two- and three-particle charge-dependent azimuthal correlations in the pseudo-rapidity range η<0.8|\eta| < 0.8 are presented as a function of the collision centrality, particle separation in pseudo-rapidity, and transverse momentum. A clear signal compatible with a charge-dependent separation relative to the reaction plane is observed, which shows little or no collision energy dependence when compared to measurements at RHIC energies. This provides a new insight for understanding the nature of the charge dependent azimuthal correlations observed at RHIC and LHC energies.Comment: 12 pages, 3 captioned figures, authors from page 2 to 6, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/286

    A note on comonotonicity and positivity of the control components of decoupled quadratic FBSDE

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    In this small note we are concerned with the solution of Forward-Backward Stochastic Differential Equations (FBSDE) with drivers that grow quadratically in the control component (quadratic growth FBSDE or qgFBSDE). The main theorem is a comparison result that allows comparing componentwise the signs of the control processes of two different qgFBSDE. As a byproduct one obtains conditions that allow establishing the positivity of the control process.Comment: accepted for publicatio
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