149 research outputs found

    Gas Exchange Relations of Ungrafted Grapevines (cv. Carménère) Growing Under Irrigated Field Conditions

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    A study was carried out to evaluate the leaf gas exchange relations and water-use efficiency (WUE) of ungrafted Carménère (Vitis vinifera L.) grapevines growing under field conditions and different levels of water stress. Stomatal conductance (gs), transpiration (E), net CO2 assimilation (AN) and stem water potential (Ψs) were measured at midday in a drip-irrigated commercial vineyard located in the Maule Valley (Chile) during three growing seasons (2005 to 2009). In addition, the instantaneous (AN/E) and intrinsic (AN/gs) water-use efficiencies and stomatal sensitivity factor (k) were estimated for the own-rooted grapevines. In this study a significant non-linear relationship was observed between AN and gs (r2 = 0.82), with values of AN decreasing from 14.9 to 3.5 μmol/m2/sec as gs diminished from 0.5 to 0.05 mol/m2/sec. This resulted in a progressive increase in WUEi (intrinsic water use efficiency). A significant linear relationship was observed between Ψs and gs (r2 = 0.39) for measurements taken before and after véraison, with an increasing scattering from -1.6 to -0.4 MPa. Finally, k decreased as water stress increased, with values of 234 and 120 for no and severe water stress respectively, while k ranged from 264 to 480 and 255 to 297 for the measurements taken before and after véraison respectively. Based on the results obtained in the present study, the cultivar Carménère could be classified as drought tolerant at low water potentials, with a large range of physiological parameters changing in response to water stress

    Hydric behaviour and gas exchange in different grapevine varieties (Vitis vinifera L.) from the Maule Valley (Chile)

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    In the near future, stomatal behaviour will be crucial to counteract conditions arising from climate change.  Grapevine varieties are classified as either isohydric or anisohydric, depending on the sensitivity of stomatato water deficit and on their water potential homeostasis. However, the great variability observed in different studies indicates that a continuum exists in the range of stomatal sensitivity to water stress. Thus, more knowledge about the hydric behaviour and the gas exchange of isohydric and anisohydric grapevine varieties under different water conditions could lead to the development of irrigation strategies oriented at improving water-use efficiency, yield and berry composition. In this study, research was conducted in order to characterise the stomatal regulation of four different Vitis vinifera L. varieties, namely Pinot noir, Sauvignon blanc, Chardonnay and Merlot, according to soil water status. Measurements of leaf gas exchange, together with measurements of stem water potential (Ψs) and leaf water potential (Ψl), were taken during two seasons. Under conditions of water stress, Chardonnay and Merlot reached a minimum Ψs of -1.67 and -1.68 MPa respectively, and higher levels of water-use efficiency (AN/gs), of 62.3 and 69.7 μmol CO2/mol H2O respectively. In Sauvignon blanc and Pinot noir, the minimum Ψs was -1.26 and -1.40 MParespectively, with lower levels of AN/gs (53.1 and 50.5 μmol CO2/mol H2O, respectively). Under conditions of water stress (Ψl < -0.9 MPa and Ψs < -0.6 MPa), all varieties had a significantly increased AN/gs1, despitea significant reduction in gas exchange. Therefore, the hydric behaviour and gas exchange observed in this study suggest that Chardonnay and Merlot could be characterised as anisohydric varieties, as they present less sensitive stomatal control, while Pinot noir can be classified as a near-anisohydric variety and Sauvignon blanc as an isohydric variety. New investigations should consider other characteristics of the varieties to classify them better

    Computing Exact Solutions to a Generalized Lax-Sawada-Kotera-Ito Seventh-Order KdV Equation

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    The Cole-Hopf transform is used to construct exact solutions to a generalization of both the seventh-order Lax KdV equation (Lax KdV7) and the seventh-order Sawada-Kotera-Ito KdV equation (Sawada-Kotera-Ito KdV7)

    Towards an empirical model to estimate the spatial variability of grapevine phenology at the within field scale

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    The aim of this study is to propose an empirical spatial model to estimate the spatial variability of grapevine phenology at the within-field scale. This spatial model allows the characterization of the spatial variability of a given variable of the fields through a single measurement performed in the field (reference site) and a combination of site-specific coefficients calculated through historical information. This approach was compared to classical approaches requiring extensive sampling and phenology models based on climatic data, which do not consider the spatial variability of the field. The study was conducted on two fields of Vitis vinifera, one of cv Cabernet Sauvignon (CS, 1.56 ha) and the other one of cv Chardonnay (CH, 1.66 ha) located in Maule Valley, Chile. Date of occurrence of grapevine phenology (budburst, flowering and veraison) were observed at the within field level following a regular sampling grid during 4 seasons for cv CS and 2 seasons for cv CH. The best results were obtained with the devised spatial model in almost all cases, with a Root Mean Square Errors (RMSE) lower than 3 days. However, if the variability of phenology is low, the traditional method of sampling could lead to better results. This study is the first step towards a modeling of the spatial variability of grapevine phenology at the within-field scale. To be fully operational in commercial vineyards, the calibration process needs simplification, for example, using low cost, inexpensive ancillary information to zone vineyards according to grapevine phenology

    Lactancia materna ineficaz: prevalencia y factores asociados

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    RESUMENIntroducción: Es posible evitar muertes neonatales mediante la lactancia materna desde el primer día devida, pues la leche materna es el alimento óptimo para el lactante por su contenido nutricional necesariofavorecer el crecimiento y desarrollo. Objetivo: Determinar la prevalencia y factores asociados aldiagnóstico de enfermería “Lactancia materna ineficaz” en lactantes menores de 6 meses hospitalizados enuna institución de tercer nivel.Metodología: Estudio de corte transversal. Se seleccionaron 108 binomios(madre e hijo) hospitalizados en una institución de tercer nivel de atención en el año 2009, se aplicó unformato validado para identificar el diagnóstico. Se realizó análisis Rasch a las variables que representanlas características definitorias del diagnóstico, con el cual se creó una escala de 0 a 100 y se construyóun modelo de regresión lineal con las variables asociadas a la medida del diagnóstico.Resultados:la prevalencia del diagnóstico fue de 93,5 %, la característica definitoria más fácil de encontrar fueIncapacidad del lactante para agarrarse al pecho materno y la más difícil fue agitación y llanto del lactantedentro de la primera hora después de la lactancia materna. La regresión lineal mostró factores asociadoscomo: género femenino, peso del lactante y necesidad de la madre de ir a orinar.Conclusiones: Existeuna tendencia desfavorable tanto en la prevalencia como en la duración de la lactancia materna para loslactantes hospitalizados; la promoción de la lactancia materna debe ser un trabajo interdisciplinario;modificar las normas hospitalarias favoreciendo el contacto del binomio y la puesta temprana al pechomaterno. Salud UIS 2011; 43 (3): 271-279Palabras clave: Lactancia materna, diagnóstico de enfermería, lactante, prevalencia,factores asociadosABSTRACTIntroduction: neonatal deaths can be prevented by breastfeeding from the first day of life, as is the optimal foodfor infants by their nutritional content required for better growth and development.Objective: To determine theprevalence and associated factors with nursing diagnosis “ineffective breastfeeding” in infants under than 6 monthshospitalized in a tertiary institution.Methodology: Cross sectional study. We selected 108 pairs (mother and child)hospitalized in an institution of tertiary care in 2009, we applied a validated format to identify the diagnosis. Raschanalysis was performed for variables that represent the defining characteristics of the diagnosis, which created ascale of 0 to 100 and built a linear regression model the variables associated with the extent of diagnosis.Results:Prevalence of diagnosis was 93,5 %, the defining characteristic was easier to find the infant’s inability to hold onto the breast and the hardest was shaking and crying of the infant within the first hour after breastfeeding. Linearregression was associated factors such as: female gender, weight infant and the mother need to urinate.Conclusions:There is an unfavorable trend in both the prevalence and duration of breastfeeding for infants hospitalized, promotionof breastfeeding should be an interdisciplinary, modify hospital policies favoring the contact of the binomial and theearly start to the chest maternal. Salud UIS 2011; 43 (3): 271-279Keywords: Breastfeeding, nursing diagnosis, infant, prevalence, associated factor

    Lactancia materna ineficaz: prevalencia y factores asociados

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    RESUMENIntroducción: Es posible evitar muertes neonatales mediante la lactancia materna desde el primer día devida, pues la leche materna es el alimento óptimo para el lactante por su contenido nutricional necesariofavorecer el crecimiento y desarrollo. Objetivo: Determinar la prevalencia y factores asociados aldiagnóstico de enfermería “Lactancia materna ineficaz” en lactantes menores de 6 meses hospitalizados enuna institución de tercer nivel.Metodología: Estudio de corte transversal. Se seleccionaron 108 binomios(madre e hijo) hospitalizados en una institución de tercer nivel de atención en el año 2009, se aplicó unformato validado para identificar el diagnóstico. Se realizó análisis Rasch a las variables que representanlas características definitorias del diagnóstico, con el cual se creó una escala de 0 a 100 y se construyóun modelo de regresión lineal con las variables asociadas a la medida del diagnóstico.Resultados:la prevalencia del diagnóstico fue de 93,5 %, la característica definitoria más fácil de encontrar fueIncapacidad del lactante para agarrarse al pecho materno y la más difícil fue agitación y llanto del lactantedentro de la primera hora después de la lactancia materna. La regresión lineal mostró factores asociadoscomo: género femenino, peso del lactante y necesidad de la madre de ir a orinar.Conclusiones: Existeuna tendencia desfavorable tanto en la prevalencia como en la duración de la lactancia materna para loslactantes hospitalizados; la promoción de la lactancia materna debe ser un trabajo interdisciplinario;modificar las normas hospitalarias favoreciendo el contacto del binomio y la puesta temprana al pechomaterno. Salud UIS 2011; 43 (3): 271-279Palabras clave: Lactancia materna, diagnóstico de enfermería, lactante, prevalencia,factores asociadosABSTRACTIntroduction: neonatal deaths can be prevented by breastfeeding from the first day of life, as is the optimal foodfor infants by their nutritional content required for better growth and development.Objective: To determine theprevalence and associated factors with nursing diagnosis “ineffective breastfeeding” in infants under than 6 monthshospitalized in a tertiary institution.Methodology: Cross sectional study. We selected 108 pairs (mother and child)hospitalized in an institution of tertiary care in 2009, we applied a validated format to identify the diagnosis. Raschanalysis was performed for variables that represent the defining characteristics of the diagnosis, which created ascale of 0 to 100 and built a linear regression model the variables associated with the extent of diagnosis.Results:Prevalence of diagnosis was 93,5 %, the defining characteristic was easier to find the infant’s inability to hold onto the breast and the hardest was shaking and crying of the infant within the first hour after breastfeeding. Linearregression was associated factors such as: female gender, weight infant and the mother need to urinate.Conclusions:There is an unfavorable trend in both the prevalence and duration of breastfeeding for infants hospitalized, promotionof breastfeeding should be an interdisciplinary, modify hospital policies favoring the contact of the binomial and theearly start to the chest maternal. Salud UIS 2011; 43 (3): 271-279Keywords: Breastfeeding, nursing diagnosis, infant, prevalence, associated factor

    Lactancia materna ineficaz: prevalencia y factores asociados

    Get PDF
    RESUMENIntroducción: Es posible evitar muertes neonatales mediante la lactancia materna desde el primer día devida, pues la leche materna es el alimento óptimo para el lactante por su contenido nutricional necesariofavorecer el crecimiento y desarrollo. Objetivo: Determinar la prevalencia y factores asociados aldiagnóstico de enfermería “Lactancia materna ineficaz” en lactantes menores de 6 meses hospitalizados enuna institución de tercer nivel.Metodología: Estudio de corte transversal. Se seleccionaron 108 binomios(madre e hijo) hospitalizados en una institución de tercer nivel de atención en el año 2009, se aplicó unformato validado para identificar el diagnóstico. Se realizó análisis Rasch a las variables que representanlas características definitorias del diagnóstico, con el cual se creó una escala de 0 a 100 y se construyóun modelo de regresión lineal con las variables asociadas a la medida del diagnóstico.Resultados:la prevalencia del diagnóstico fue de 93,5 %, la característica definitoria más fácil de encontrar fueIncapacidad del lactante para agarrarse al pecho materno y la más difícil fue agitación y llanto del lactantedentro de la primera hora después de la lactancia materna. La regresión lineal mostró factores asociadoscomo: género femenino, peso del lactante y necesidad de la madre de ir a orinar.Conclusiones: Existeuna tendencia desfavorable tanto en la prevalencia como en la duración de la lactancia materna para loslactantes hospitalizados; la promoción de la lactancia materna debe ser un trabajo interdisciplinario;modificar las normas hospitalarias favoreciendo el contacto del binomio y la puesta temprana al pechomaterno. Salud UIS 2011; 43 (3): 271-279Palabras clave: Lactancia materna, diagnóstico de enfermería, lactante, prevalencia,factores asociadosABSTRACTIntroduction: neonatal deaths can be prevented by breastfeeding from the first day of life, as is the optimal foodfor infants by their nutritional content required for better growth and development.Objective: To determine theprevalence and associated factors with nursing diagnosis “ineffective breastfeeding” in infants under than 6 monthshospitalized in a tertiary institution.Methodology: Cross sectional study. We selected 108 pairs (mother and child)hospitalized in an institution of tertiary care in 2009, we applied a validated format to identify the diagnosis. Raschanalysis was performed for variables that represent the defining characteristics of the diagnosis, which created ascale of 0 to 100 and built a linear regression model the variables associated with the extent of diagnosis.Results:Prevalence of diagnosis was 93,5 %, the defining characteristic was easier to find the infant’s inability to hold onto the breast and the hardest was shaking and crying of the infant within the first hour after breastfeeding. Linearregression was associated factors such as: female gender, weight infant and the mother need to urinate.Conclusions:There is an unfavorable trend in both the prevalence and duration of breastfeeding for infants hospitalized, promotionof breastfeeding should be an interdisciplinary, modify hospital policies favoring the contact of the binomial and theearly start to the chest maternal. Salud UIS 2011; 43 (3): 271-279Keywords: Breastfeeding, nursing diagnosis, infant, prevalence, associated factor

    Efectividad y seguridad comparada de inhibidores del cotransportador sodio-glucosa tipo 2 (iSGLT2) en diabetes mellitus tipo 2: revisión rápida de revisiones sistemáticas y metaanálisis

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    Objetivo: recopilar y evaluar la evidencia disponible respecto a la efectividad y seguridad comparada de inhibidores del cotransportador de sodio glucosa tipo 2 (iSGLT2) en pacientes con diabetes mellitus tipo 2. Metodología: se realizó una revisión sistemática rápida de revisiones sistemáticas de iSGLT2 en las bases de datos Medline y Embase hasta septiembre de 2019. El desenlace primario cardiovascular incluyó eventos adversos cardiovasculares mayores (MACE) que corresponden a muerte por causa cardiovascular, ataque cerebrovascular (ACV) no fatal, infarto agudo de miocardio (IAM) no fatal, además de hospitalización por insuficiencia cardíaca; desenlace renal (definido como progresión de enfermedad renal), disminución de la tasa de filtración glomerular (TFG) y de la relación albuminuria-creatinuria. El desenlace de seguridad agrupó hipoglucemia, fracturas, infecciones urinarias, entre otros. La calidad metodológica de las revisiones se evaluó con el instrumento A measurement Tool to Assess Systematic Review (AMSTAR-2) modificado. Resultados: se incluyeron 5 revisiones sistemáticas de la literatura de calidad media y alta según AMSTAR-2 modificado, entre las cuales se encontró que los iSGLT2 reducen el riesgo de mortalidad cardiovascular en un 23 %, de mortalidad por todas las causas en 20 % y en admisión hospitalaria por insuficiencia cardíaca en un 33 %, en comparación con el cuidado estándar. En cuanto al desenlace renal, los iSGLT2 enlentecen el deterioro de la enfermedad renal y reducen la progresión a albuminuria en pacientes con proteinuria ya documentada. En el desenlace de seguridad se observa una mayor posibilidad de desarrollar infecciones del tracto genitourinario respecto a antidiabéticos orales. Conclusiones: la evidencia sugiere que los iSGLT2 son efectivos en la reducción del riesgo de mortalidad cardiovascular, de mortalidad por todas las causas, de admisión hospitalaria por insuficiencia cardíaca, de progresión de la nefropatía y del desarrollo de enfermedad renal en estadio final. En desenlaces de seguridad, la evidencia sugiere que los iSGLT2 tienen menor riesgo de eventos de hipoglucemia

    Red deer reveal spatial risks of Crimean-Congo haemorrhagic fever virus infection

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    In press.Crimean-Congo haemorrhagic fever virus (CCHFV) continues to cause new human cases in Iberia while its spatial distribution and ecological determinants remain unknown. The virus remains active in a silent tick-animal cycle to which animals contribute maintaining the tick populations and the virus itself. Wild ungulates, in particular red deer, are essential hosts for Hyalomma ticks in Iberia, which are the principal competent vector of CCHFV. Red deer could be an excellent model to understand the ecological determinants of CCHFV as well as to predict infection risks for humans because it is large, gregarious, abundant and the principal host for Hyalomma lusitanicum. We designed a cross-sectional study, analysed the presence of CCHFV antibodies in 1444 deer from 82 populations, and statistically modelled exposure risk with host and environmental predictors. The best-fitted statistical model was projected for peninsular Spain to map infection risks. Fifty out of 82 deer populations were seropositive, with individual population prevalence as high as 88%. The highest prevalence of exposure to CCHFV occurred in the southwest of the Iberian Peninsula. Climate and ungulate abundance were the most influential predictors of the risk of exposure to the virus. The highest risk regions were those where H. lusitanicum is most abundant. Eight of the nine primary human cases occurred in or bordering these regions, demonstrating that the model predicts human infection risk accurately. A recent human case of CCHF occurred in northwestern Spain, a region that the model predicted as low risk, pointing out that it needs improvement to capture all determinants of the CCHFV infection risk. In this study, we have been able to identify the main ecological determinants of CCHFV, and we have also managed to create an accurate model to assess the risk of CCHFV infection.This study has been funded by the Spanish Ministry for the Science and Innovation (MCI) through projects CGL2017-89866-R & E-RTA2015-0002-C02-02, and by the Regional Government of Castilla-La Mancha and the European Social Fund (ESF) through project SBPLY/19/180501/000321. RC-M, LC-M, SJ-R and JM-G would like to thank the MCI, ESF and the University of Castilla-La Mancha for their support through contracts PRE2018-083801, PEJ2018-003155-A, 2018/12504 and BES-2015-072206, respectively. BC was supported by FCT-Fundação para a Ciência e Tecnologia (2020.04872.BD). DG-B would like to thank MCI and Instituto de Salud Carlos III (CD19CIII/00011) for funding him.Peer reviewe

    Bead-assisted SARS-CoV-2 multi-antigen serological test allows effective identification of patients

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    Many new aspects of COVID-19 disease, including different clinical manifestations, have been identified during the pandemic. The wide array of symptoms and variation in disease severity after SARS-CoV-2 infection might be related to heterogeneity in the immune responses of different patients. Here we describe a new method for a simple multi-antigen serological test that generates a full picture of seroconversion in a single reaction. The assay is based on the detection by flow cytometry of multiple immunoglobulin classes (isotypes) specific for four SARS-CoV-2 antigens: the Spike glycoprotein (one of the highly immunogenic proteins), its RBD fragment (the major target for neutralising antibodies), the nucleocapsid protein and the main cysteine-like protease. Until now, most diagnostic serological tests measured antibodies to only one antigen and some patients seemed to not make any antibody response. Our data reveal that while most patients respond against all the viral antigens tested, others show a marked bias to make antibodies against either proteins exposed on the viral particle or those released after cellular infection. Combining all the four antigens and using machine learning techniques, it was possible to clearly discriminate between patients and healthy controls with 100% confidence. Further, combination of antigens and different immunoglobulin isotypes in this multi-antigen assay improved the classification of patients with mild and severe disease. Introduction of this method will facilitate massive screenings of patients to evaluate their immune response. It could also support vaccination campaigns both to select non-immune individuals and to distinguish infected patients from vaccine responders.This work was supported by the Spanish National Research Council (CSIC, project numbers 202020E079 and CSIC-COVID19-028) and grants from Madrid Regional Government “IMMUNOTHERCAN” [S2017/BMD-3733-2 (MVG)]; the Spanish Ministry of Science and Innovation [(MCIU/AEI/FEDER, EU): RTI2018-093569-B-I00 (MVG), SAF2017-82940-R (JMRF), SAF2017-83265-R (HTR); SAF2017-82886-R (FSM)]; Health Institute Carlos III (ISCIII) [RETICS Program RD16/0012/0006; RIER (JMRF); PI19/00549 (AA)]. The study was also funded by “La Caixa Banking Foundation” (HR17-00016 to FSM) and Fondo Supera COVID (CRUE-Banco de Santander) to FSM.N
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