93 research outputs found

    Modelagem espaço-temporal do padrão de infestação da broca do café levando em consideração excesso de zeros e dados faltantes

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    The study of pest distributions in space and time in agricultural systems provides important information for the optimization of integrated pest management programs and for the planning of experiments. Two statistical problems commonly associated to the space-time modelling of data that hinder its implementation are the excess of zero counts and the presence of missing values due to the adopted sampling scheme. These problems are considered in the present article. Data of coffee berry borer infestation collected under Colombian field conditions are used to study the spatio-temporal evolution of the pest infestation. The dispersion of the pest starting from initial focuses of infestation was modelled considering linear and quadratic infestation growth trends as well as different combinations of random effects representing both spatially and not spatially structured variability. The analysis was accomplished under a hierarchical Bayesian approach. The missing values were dealt with by means of multiple imputation. Additionally, a mixture model was proposed to take into account the excess of zeroes in the beginning of the infestation. In general, quadratic models had a better fit than linear models. The use of spatially structured parameters also allowed a clearer identification of the temporal increase or decrease of infestation patterns. However, neither of the space-time models based on standard distributions was able to properly describe the excess of zero counts in the beginning of the infestation. This overdispersed pattern was correctly modelled by the mixture space-time models, which had a better performance than their counterpart without a mixture component.O estudo da distribuição de pragas em espaço e tempo em sistemas agrícolas fornece informação importante para a otimização de programas de manejo integrado de pragas e para o planejamento de experimentos. Dois problemas estatísticos comumente associados à modelagem espaço-temporal desse tipo de dados que dificultam sua implementação são o excesso de zeros nas contagens e a presença de dados faltantes devido ao esquema de amostragem adotado. Esses problemas são considerados no presente artigo. Para estudar a evolução da infestação da broca do café a partir de focos iniciais de infestação foram usados dados de infestação da praga coletados em condições de campo na Colômbia. Foram considerados modelos com tendência de crescimento da infestação linear e quadrática, assim como diferentes combinações de efeitos aleatórios representando variabilidade espacialmente estruturada e não estruturada. As análises foram feitas sob uma abordagem Bayesiana hierárquica. O método de imputação múltipla foi usado para abordar o problema de dados faltantes. Adicionalmente, foi proposto um modelo de mistura para levar em consideração o excesso de zeros nas contagens no início da infestação. Em geral, os modelos quadráticos tiveram um melhor ajuste que os modelos lineares. O uso de parâmetros espacialmente estruturados permitiu uma identificação mais clara dos padrões temporais de acréscimo ou decréscimo na infestação. No entanto, nenhum dos modelos espaço-tempo baseados em distribuições padrões descreveu, apropriadamente, o excesso de zeros no início da infestação. Esse padrão de sobredispersão foi corretamente modelado pelos modelos de mistura espaço-tempo, os quais tiveram um melhor desempenho que seus homólogos sem mistura.CNP

    La formación espacial de los valores comerciales, un análisis para las principales ciudades catalanas

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    La presente comunicación reporta los resultados de una investigación que tiene por objeto conocer cuáles son los factores que determinan el valor de los locales comerciales en las principales ciudades catalanas. A través de un análisis econométrico, construido a partir de un estudio de mercado propio, se analiza cuál es el peso que los factores locativos y las características de los locales tienen, sobre la formación espacial de los valores. A estos efectos, la información de los locales ubicados a pie de calle en venta y alquiler (antigüedad del inmueble, estado de conservación de los acabados e instalaciones, tipos de acabados, lementos accesorios, geométricos y configuración espacial de los locales) ha sido complementada, mediante un SIG, con otra derivada de la localización (cercanía a los ejes principales, composición socioeconómica del entorno, nivel de accesibilidad, estructura edificada, usos del suelo predominantes, etc.) procedente del Censo de Edificios, Locales, Población y Vivienda del 2001, así como del Corine Landcover 2000. Los resultados sugieren que detrás de los factores locativos están otros asociados a las características estructurales de los locales, como su configuración, y que tienen una directa relación con el nivel de accesibilidad y visualización que se tiene del local desde la vía pública.This communication reports the results of an investigation that seeks to identify the factors that determine the value of commercial premises in the main cities in Catalonia. Through an econometric analysis, built from a separate market study, we analyze what are the weight factors and the characteristics of rental premises are on the spatial formation of values. For this purpose, information from the premises to the street for sale and rent (length of the property, the conservation status of finishes and facilities, types of finishes, accessories, geometric and spatial configuration of the premises) has been supplemented through a GIS, with another due to location (proximity to the main composition of the socioeconomic environment, level of accessibility, built structure, land use dominate, etc..) from the Census of Buildings, Local Population and Housing 2001, and the Corine Landcover 2000. The results suggest that behind the rental are other factors associated with the structural characteristics of the premises, as its configuration, and have a direct relation to the level of accessibility and visualization that is from the local public roads.Peer Reviewe

    Highly porous and conductive functional carbon fibers from electrospun phosphorus-containing lignin fibers

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    Functional carbon fibers were prepared by carbonization of thermostabilized electrospun lignin-fibers at 500–900 °C followed by a high temperature thermal treatment at 1200–1600 °C. The effect of the preparation temperature on their surface chemistry, structural order, textural properties and electrochemical behavior has been stablished. Maximum porosity development is obtained at 900 °C. The addition of phosphoric acid in the electrospinning lignin solution shortens the stabilization time of the fibers, increases the carbonization yield, generates phosphorus functional groups (P content as high as 3% wt.) and increases the BET surface area of carbon fibers from 840 to 1143 m2 g−1. Interestingly, when phosphorus-containing carbon fibers are treated even at very high temperature, 1600 °C, most of the porosity is preserved (ABET = 822 m2 g−1). XPS depth profile reveals the presence of reduced phosphorus in the core of carbonized fibers. XRD and TEM analysis make evident that the presence of phosphorus induces curvature of the graphitic layers, which seems to hinder the stacking of the graphene layers, explaining the preservation of microporosity after the thermal treatment at high temperature. However, Raman and XRD analyses point out that the presence of phosphorus does not affect the lateral growing of the crystallites. Thus, phosphorus preserves the porosity and allows the development of the electrical conductivity after the thermal treatments. Gravimetric capacitances of 79 F g−1 and capacitance retention of 63% at 68 A g−1 have been determined for phosphorus-containing carbon fibers prepared at 1200 °CWe gratefully thank MICINN (RTI2018-097555-B-100) and Junta de Andalucía (UMA18-FEDERJA-110 and P18-RT-4592) for financial support. Funding for open access charge: Universidad de M ́alaga / CBUA

    Role of bacterial community composition as a driver of the small-sized phytoplankton community structure in a productive coastal system

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    Financiado para publicación en acceso aberto: Universidade de Vigo/CISUGWe present here the first detailed description of the seasonal patterns in bacterial community composition (BCC) in shelf waters off the Ría de Vigo (Spain), based on monthly samplings during 2 years. Moreover, we studied the relationship between bacterial and small-sized eukaryotic community composition to identify potential biotic interactions among components of these two communities. Bacterial operational taxonomic unit (OTU) richness and diversity systematically peaked in autumn–winter, likely related to low resource availability during this period. BCC showed seasonal and vertical patterns, with Rhodobacteraceae and Flavobacteriaceae families dominating in surface waters, and SAR11 clade dominating at the base of the photic zone (30 m depth). BCC variability was significantly explained by environmental variables (e.g., temperature of water, solar radiation, or dissolved organic matter). Interestingly, a strong and significant correlation was found between BCC and small-sized eukaryotic community composition (ECC), which suggests that biotic interactions may play a major role as structuring factors of the microbial plankton in this productive area. In addition, co-occurrence network analyses revealed strong and significant, mostly positive, associations between bacteria and small-sized phytoplankton. Positive associations likely result from mutualistic relationships (e.g., between Dinophyceae and Rhodobacteraceae), while some negative correlations suggest antagonistic interactions (e.g., between Pseudo-nitzchia sp. and SAR11). These results support the key role of biotic interactions as structuring factors of the small-sized eukaryotic community, mostly driven by positive associations between small-sized phytoplankton and bacteria.Xunta de Galicia | Ref. EM2013/023Xunta de Galicia | Ref. ED481A-2019/290Xunta de Galicia | Ref. ED431I 2020/03Ministerio de Economía y Competitividad | Ref. CTM2017-83362-RMinisterio de Ciencia e Innovación | Ref. PID2019-110011RB-C3

    Cisplatin resistance involves a metabolic reprogramming through ROS and PGC-1α in NSCLC which can be overcome by OXPHOS inhibition

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    Background: Platinum-based chemotherapy remains the standard of care for most lung cancer cases. However chemoresistance is often developed during the treatment, limiting clinical utility of this drug. Recently, the ability of tumor cells to adapt their metabolism has been associated to resistance to therapies. In this study, we first described the metabolic reprogramming of Non-Small Cell Lung Cancer (NSCLC) in response to cisplatin treatment. Methods: Cisplatin-resistant versions of the A549, H1299, and H460 cell lines were generated by continuous drug exposure. The long-term metabolic changes, as well as, the early response to cisplatin treatment were analyzed in both, parental and cisplatin-resistant cell lines. In addition, four Patient-derived xenograft models treated with cisplatin along with paired pre- and post-treatment biopsies from patients were studied. Furthermore, metabolic targeting of these changes in cell lines was performed downregulating PGC-1α expression through siRNA or using OXPHOS inhibitors (metformin and rotenone). Results: Two out of three cisplatin-resistant cell lines showed a stable increase in mitochondrial function, PGC1-α and mitochondrial mass with reduced glycolisis, that did not affect the cell cycle. This phenomenon was confirmed in vivo. Post-treatment NSCLC tumors showed an increase in mitochondrial mass, PGC-1α and a decrease in the GAPDH/MT-CO1 ratio. In addition, we demonstrated how a ROS-mediated metabolism reprogramming, involving PGC-1α and increased mitochondrial mass, is induced during short-time cisplatin exposure. Moreover, we tested how cells with increased PGC-1a induced by ZLN005 treatment, showed reduced cisplatin-driven apoptosis. Remarkably, the long-term metabolic changes, as well as the metabolic reprogramming during short-time cisplatin exposure can be exploited as an Achilles’ heel of NSCLC cells, as demonstrated by the increased sensitivity to PGC-1α interference or OXPHOS inhibition using metformin or rotenone. Conclusion: These results describe a new cisplatin resistance mechanism in NSCLC based on a metabolic reprogramming that is therapeutically exploitable through PGC-1α downregulation or OXPHOS inhibitors.Work in the authors’ laboratories is supported by ‘‘Instituto de Salud Carlos III’’ PI13/01806 and PIE14/0064 to M.P. A.C-B, received a Spanish Lung Cancer Group fellowship. R.L-B, is supported by Comunidad Autónoma de Madrid “Garantía juvenil” contrac

    New direct alcohol and hydrogen fuel cells for naval and aeronautical applications (PILCONAER)

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    In the current context of demand for reliable, low cost and low environmental impact energy sources, many countries and companies are mostly focused on fuel cells (FC) in fields as transportation and stationary power generation and portable devices. Lately, FCs have begun to be applied in naval and aeronautical systems due to its high efficiency, low noise and environmental advantages. These applications could range from propulsion systems to auxiliary power units(APU). The main problems associated with the use of FCs in these areas are the current high cost due to the materials used, i.e. Nafion and Pt, the lack of durability testing in these specific conditions, security issues to flammability and high H2 pressures and low availability as a fuel, or the toxicity of methanol used as a fuel, and specific parameters such as weight in aircraft applications and volume in marine applications. Currently it is working on each of these issues, and at this point the ethanol as direct fuel is considered crucial. The use of ethanol as fuel has the advantage of easy transportation, storage and refueling, and is nontoxic. Bioethanol is a promising energy source, produced from raw materials containing sugar or starch. These raw materials exists in all parts of the world and is renewable, which involves the use of local energy sources contributing to the diversification of energy supply, reducing import dependence, increasing security of supply and generating new opportunities for agriculture. The main objective of the project is the development of low power stacks (stacks) fed with methanol (DMFC)and ethanol (DEFC) based on the development of new catalysts and membranes. PILCONAER aims contributing to the development of a sustainable use technology, further commitment to the restoration of the natural environment and biodiversity conservation

    Central nervous system involvement in systemic lupus erythematosus: data from the Spanish Society of Rheumatology Lupus Register (RELESSER)

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    Objectives: To analyze the prevalence, incidence, survival and contribution on mortality of major central nervous system (CNS) involvement in systemic lupus erythematosus (SLE). Methods: Patients fulfilling the SLE 1997 ACR classification criteria from the multicentre, retrospective RELESSER-TRANS (Spanish Society of Rheumatology Lupus Register) were included. Prevalence, incidence and survival rates of major CNS neuropsychiatric (NP)-SLE as a group and the individual NP manifestations cere-brovascular disease (CVD), seizure, psychosis, organic brain syndrome and transverse myelitis were calculated. Furthermore, the contribution of these manifestations on mortality was analysed in Cox regression models adjusted for confounders. Results: A total of 3591 SLE patients were included. Of them, 412 (11.5%) developed a total of 522 major CNS NP-SLE manifestations. 61 patients (12%) with major CNS NP-SLE died. The annual mortality rate for patients with and without ever major CNS NP-SLE was 10.8% vs 3.8%, respectively. Individually, CVD (14%) and organic brain syndrome (15.5%) showed the highest mortality rates. The 10% mortality rate for patients with and without ever major CNS NP-SLE was reached after 12.3 vs 22.8 years, respectively. CVD (9.8 years) and organic brain syndrome (7.1 years) reached the 10% mortality rate earlier than other major CNS NP-SLE manifestations. Major CNS NP-SLE (HR 1.85, 1.29-2.67) and more specifically CVD (HR 2.17, 1.41-3.33) and organic brain syndrome (HR 2.11, 1.19-3.74) accounted as independent prognostic factors for poor survival. Conclusion: The presentation of major CNS NP-SLE during the disease course contributes to a higher mortality, which may differ depending on the individual NP manifestation. CVD and organic brain syndrome are associated with the highest mortality rates.Pathophysiology and treatment of rheumatic disease

    A Contribution of the HAWC Observatory to the TeV era in the High Energy Gamma-Ray Astrophysics: The case of the TeV-Halos

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    We present a short overview of the TeV-Halos objects as a discovery and a relevant contribution of the High Altitude Water \v{C}erenkov (HAWC) observatory to TeV astrophysics. We discuss history, discovery, knowledge, and the next step through a new and more detailed analysis than the original study in 2017. TeV-Halos will contribute to resolving the problem of the local positron excess observed on the Earth. To clarify the latter, understanding the diffusion process is mandatory.Comment: Work presented in the 21st International Symposium on Very High Energy Cosmic Ray Interactions(ISVHECRI 2022) as part of the Ph. D. Thesis of Ramiro Torres-Escobedo (SJTU, Shanghai, China). Accepted for publication in SciPost Physics Proceedings (ISSN 2666-4003). 11 pages, 3 Figures. Short overview of HAWC and TeV Halos objects until 202

    Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

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    The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality
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