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3.
J Exp Bot ; 74(16): 4825-4846, 2023 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-37490359

RESUMO

Adequate management of N supply, plant density, row spacing, and soil cover has proved useful for increasing grain yields and/or grain yield stability of rainfed crops over the years. We review the impact of these management practices on grain yield water-related determinants: seasonal crop evapotranspiration (ET) and water use efficiency for grain production per unit of evapotranspired water during the growing season (WUEG,ET,s). We highlight a large number of conflicting results for the impact of management on ET and expose the complexity of the ET response to environmental factors. We analyse the influence of management practices on WUEG,ET,s in terms of the three main processes controlling it: (i) the proportion of transpiration in ET (T/ET), (ii) transpiration efficiency for shoot biomass production (TEB), and (iii) the harvest index. We directly relate the impact of management practices on T/ET to their effect on crop light interception and provide evidence that management practices significantly influence TEB. To optimize WUEG,ET,s, management practices should favor soil water availability during critical periods for seed set, thereby improving the harvest index. The need to improve the performance of existing crop growth models for the prediction of water-related grain yield determinants under different management practices is also discussed.


Assuntos
Solo , Água , Água/fisiologia , Grão Comestível , Produtos Agrícolas , Sementes
4.
Salud ment ; 46(2): 97-104, Mar.-Apr. 2023. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1450420

RESUMO

Abstract Introduction Previous data suggest that healthcare students, such as nursing students, might have a differential risk of presenting burnout syndrome caused by the stress they are subjected to. However, the evidence is still scarce and inconclusive. Objective To evaluate the association between nursing training and burnout syndrome among undergraduate students in Hidalgo, Mexico. Method A cross-sectional analytical study was conducted on 566 undergraduate students (56% were nursing students and the rest were non-healthcare students). Burnout syndrome was identified using the Spanish version of the Maslach Burnout Inventory-Student Survey, consisting of subscales: emotional exhaustion, depersonalization, and diminished academic efficacy. The association between the variables of interest was evaluated using logistic regression models adjusted for confounders. Results In the depersonalization subscale, nursing students, compared with non-healthcare students, had an adjusted Odds Ratio (aOR) of moderate/high burnout syndrome of 2.08 (95% confidence interval [CI] = [1.34, 3.22]). In addition, the association was stronger among students in the third and fourth school years (aOR = 3.58; 95% CI = [1.62, 7.89]) compared with those in the first and second school years (aOR = 1.20; 95% CI = [.71, 2.03]). Discussion and conclusion It is necessary that universities provide nursing students with tools that allow them to cope with stressful situations during their academic training and their future life as health professionals.


Resumen Introducción Datos previos sugieren que los estudiantes del cuidado a la salud, como es el caso de enfermería, podrían tener un riesgo diferencial de presentar síndrome de burnout debido al estrés al que están sometidos, no obstante, la evidencia aun es escaza y no concluyente. Objetivo Evaluar la asociación entre la formación académica en enfermería con el síndrome de burnout en estudiantes universitarios de Hidalgo, México. Método Estudio trasversal analítico realizado en una muestra de 566 estudiantes universitarios (56% eran estudiantes de enfermería y el resto de las áreas diferentes a la salud). Para determinar la presencia de síndrome de burnout se utilizó la versión en español de la escala Maslach Burnout Inventory-Student Survey, conformada por las subescalas: agotamiento, eficacia académica y despersonalización. La asociación entre las variables de interés se evalúo mediante modelos de regresión logística ajustados por confusores. Resultados En la subescala de despersonalización los estudiantes de enfermería tuvieron mayores posibilidades de presentar síndrome de burnout medio/alto en comparación con los de las otras formaciones académicas (razón de momios ajustada [RMa] = 2.08; intervalo de confianza [IC] al 95% = [1.34, 3.22]). Además, la asociación fue más fuerte entre aquellos que cursaban el tercer y cuarto año escolar (RMa = 3.58; IC 95% = [1.62, 7.89]) a diferencia de los que cursaban los primeros dos años escolares (RMa = 1.20; IC 95% = [.71, 2.03]). Discusión y conclusión Es importante que las universidades brinden a los estudiantes de enfermería herramientas que les permitan sobrellevar las situaciones estresantes durante su formación académica y su futura vida profesional.

11.
Ann Bot ; 130(1): 97-108, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35652517

RESUMO

BACKGROUND AND AIMS: The petaline operculum that covers the inner whorls until anthesis and the woody capsule that develops after fertilization are reproductive structures of eucalypts that protect the flower and seeds. Although they are distinct organs, they both develop from flower buds and this common ontogeny suggests shared genetic control. In Eucalyptus globulus their morphology is variable and we aimed to identify the quantitative trait loci (QTL) underlying this variation and determine whether there is common genetic control of these ecologically and taxonomically important reproductive structures. METHODS: Samples of opercula and capsules were collected from 206 trees that belong to a large outcrossed F2E. globulus mapping population. The morphological variation in these structures was characterized by measuring six operculum and five capsule traits. QTL analysis was performed using these data and a linkage map consisting of 480 markers. KEY RESULTS: A total of 27 QTL were detected for operculum traits and 28 for capsule traits, with the logarithm of odds ranging from 2.8 to 11.8. There were many co-located QTL associated with operculum or capsule traits, generally reflecting allometric relationships. A key finding was five genomic regions where co-located QTL affected both operculum and capsule morphology, and the overall trend for these QTL was to affect elongation of both organs. Some of these QTL appear to have a significant effect on the phenotype, with the strongest QTL explaining 26.4 % of the variation in operculum shape and 16.4 % in capsule shape. Flower bud measurements suggest the expression of these QTL starts during bud development. Several candidate genes were found associated with the QTL and their putative function is discussed. CONCLUSIONS: Variation in both operculum and capsule traits in E. globulus is under strong genetic control. Our results suggest that these reproductive structures share a common genetic pathway during flower bud development.


Assuntos
Eucalyptus , Mapeamento Cromossômico , Eucalyptus/genética , Flores/genética , Ligação Genética , Fenótipo , Locos de Características Quantitativas/genética
12.
Int J Hyg Environ Health ; 239: 113865, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34700204

RESUMO

BACKGROUND: Experimental evidence suggests that p,p'-DDE might be involved in the development of diabetes and hypertension (HTN); however, the evidence in humans is inconclusive. OBJECTIVE: To summarize the epidemiological evidence for the association of p,p'-DDT exposure and its breakdown products with the risk of diabetes and HTN from prospective studies. METHODS: We performed a systematic review and meta-analysis based on the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. Eligible studies (prospective) were search in PubMed, Web of Science, EBSCO, and SciELO databases (July 11, 2020). Different search algorithms were used for diabetes and HTN. Pooled odds ratios (ORs) were estimated from meta-analysis with random effects for each exposure and outcome. RESULTS: A total of 23 prospective studies were included in this review, 16 assessed diabetes and seven HTN; very few measured p,p'-DDT. Exposure to p,p'-DDE was associated with a slightly increased risk of type 2 diabetes (T2D) (pooled OR = 1.44; 95%CI: 1.00, 2.07; p = 0.049) and HTN (pooled OR = 1.21; 95%CI: 1.07, 1.38). Dose-response meta-analysis suggested a non-linear relation between p,p'-DDE and T2D. Exposure to p,p'-DDE was not associated with gestational diabetes (pooled OR = 1.01; 95%CI: 0.94, 1.09); similarly, p,p'-DDT was not associated with T2D (pooled OR = 1.03; 95%CI: 0.79, 1.35). CONCLUSIONS: Evidence from prospective studies suggests that exposure to p,p'-DDE, the main breakdown product of p,p'-DDT, might increase the risk of developing T2D; such increase may be apparent only at low levels. Exposure to p,p'-DDE may also increase the risk of having HTN; however, further evidence is required.


Assuntos
Diabetes Mellitus Tipo 2 , Hipertensão , Praguicidas , DDT , Diabetes Mellitus Tipo 2/epidemiologia , Diclorodifenil Dicloroetileno , Humanos , Hipertensão/epidemiologia , Estudos Prospectivos
15.
Salud Publica Mex ; 63(2, Mar-Abr): 253-261, 2021 Jan 14.
Artigo em Espanhol | MEDLINE | ID: mdl-33989483

RESUMO

 Objetivo. Resumir la evidencia científica sobre las altera-ciones renales asociadas con la infección por SARS-CoV-2. Material y métodos. Se realizó una revisión rápida con la metodología Cochrane. Resultados. La enfermedad renal crónica (ERC) preexistente en pacientes con SARS-CoV-2 varió de 1 a 38% y la lesión renal aguda (LRA), de 2.9 a 86.4%. El pronóstico de la infección fue peor en pacientes con ERC y en aquellos con reserva renal remanente (RRR) intacta que desarrollaron LRA. El riesgo de muerte fue mayor (riesgo relativo combinado = 1.49; IC95%: 1.09-2.04) en pacientes infectados por SARS-CoV-2 con ERC preexistente. Los mar-cadores de RRR mostraron alteraciones en pacientes con SARS-CoV-2 graves y fatales; el marcador más utilizado fue la creatinina sérica. Conclusiones. La evidencia científica muestra la relevancia de la evaluación y monitoreo perma-nente de la RRR en pacientes hospitalizados por SARS-CoV-2 para mejorar el pronóstico de aquellos con ERC preexistente, así como de aquellos sin ERC que desarrollan LRA.


Assuntos
COVID-19/fisiopatologia , Rim/fisiopatologia , Humanos
16.
Salud Publica Mex ; 63(2, Mar-Abr): 242-252, 2021 Feb 26.
Artigo em Espanhol | MEDLINE | ID: mdl-33989487

RESUMO

Objetivo. Resumir la evidencia científica sobre efectos maternos y neonatales del Covid-19 durante el embarazo. Material y métodos. Se realizó una revisión rápida Cochrane y un metaanálisis de proporciones y razones de momios (RM). Resultados. Los eventos maternos más comunes fueron la ventilación mecánica invasiva y admisión a la unidad de cuidados intensivos (UCI); las complicaciones del embarazo fueron el sufrimiento fetal y la ruptura prematura de membranas; las comorbilidades fueron la obesidad y el asma. Las cesáreas indicadas por Covid-19 fueron frecuentes (51%). Los eventos neonatales comunes fueron bajo peso y prematuridad; se identificaron neonatos SARS-CoV-2 posi-tivos (14%). Las embarazadas con Covid-19 experimentaron más cesáreas (RM combinada=6.7) y partos pretérmino (RM combinada=2.9); los neonatos experimentaron más admisio-nes a la UCI neonatal (RM combinada=5.9). Conclusión. La evidencia sobre los efectos adversos del Covid-19 durante el embarazo es limitada. No se pueden descartar riesgos a la salud del binomio, particularmente debido a las cesáreas y prematuridad.


Assuntos
COVID-19 , Complicações Infecciosas na Gravidez , COVID-19/complicações , COVID-19/diagnóstico , COVID-19/transmissão , Feminino , Humanos , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Resultado da Gravidez
19.
Salud pública Méx ; 63(2): 242-252, 2021. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1432233

RESUMO

Resumen: Objetivo: Resumir la evidencia científica sobre efectos maternos y neonatales del Covid-19 durante el embarazo. Material y métodos Se realizó una revisión rápida Cochrane y un metaanálisis de proporciones y razones de momios (RM). Resultados: Los eventos maternos más comunes fueron la ventilación mecánica invasiva y admisión a la unidad de cuidados intensivos (UCI); las complicaciones del embarazo fueron el sufrimiento fetal y la ruptura prematura de membranas; las comorbilidades fueron la obesidad y el asma. Las cesáreas indicadas por Covid-19 fueron frecuentes (51%). Los eventos neonatales comunes fueron bajo peso y prematuridad; se identificaron neonatos SARS-CoV-2 positivos (14%). Las embarazadas con Covid-19 experimentaron más cesáreas (RM combinada=6.7) y partos pretérmino (RM combinada=2.9); los neonatos experimentaron más admisiones a la UCI neonatal (RM combinada=5.9). Conclusión: La evidencia sobre los efectos adversos del Covid-19 durante el embarazo es limitada. No se pueden descartar riesgos a la salud del binomio, particularmente debido a las cesáreas y prematuridad.


Abstract: Objective: To summarize the scientific evidence of adverse health effects of Covid-19 during pregnancy. Materials and methods We conducted a Cochrane rapid review. Meta-analysis of proportions and odds ratios (OR) were performed. Results: Frequent maternal events included invasive mechanic ventilation and admission to the intensive care unit (ICU); pregnancy complications were fetal distress and premature rupture of membranes; common comorbidities were obesity and asthma. Deliveries by cesarean section (C-section) due to Covid-19 were frequent (51%). The most frequent neonatal outcomes were low birthweight and prematurity; we identified cases of SARS-CoV-2 positive neonates (14%). Pregnant women with Covid-19 were more likely to deliver by C-section (pooled OR=6.7) and prematurely (pooled OR=2.9); neonates were more likely to be admitted to the neonatal ICU (pooled OR=5.9). Conclusion: The available evidence on Covid-19 during pregnancy is limited. Therefore, we cannot disregard adverse health effects on the mother-child pair, particularly those related to C-sections and premature deliveries.

20.
Salud pública Méx ; 63(2): 253-261, 2021. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1432234

RESUMO

Resumen Objetivo: Resumir la evidencia científica sobre las alteraciones renales asociadas con la infección por SARS-CoV-2. Material y métodos: Se realizó una revisión rápida con la metodología Cochrane. Resultados: La enfermedad renal crónica (ERC) preexistente en pacientes con SARS-CoV-2 varió de 1 a 38% y la lesión renal aguda (LRA), de 2.9 a 86.4%. El pronóstico de la infección fue peor en pacientes con ERC y en aquellos con reserva renal remanente (RRR) intacta que desarrollaron LRA. El riesgo de muerte fue mayor (riesgo relativo combinado = 1.49; IC95%: 1.09-2.04) en pacientes infectados por SARS-CoV-2 con ERC preexistente. Los marcadores de RRR mostraron alteraciones en pacientes con SARS-CoV-2 graves y fatales; el marcador más utilizado fue la creatinina sérica. Conclusiones: La evidencia científica muestra la relevancia de la evaluación y monitoreo permanente de la RRR en pacientes hospitalizados por SARS-CoV-2 para mejorar el pronóstico de aquellos con ERC preexistente, así como de aquellos sin ERC que desarrollan LRA.


Abstract: Objective: To summarize the scientific literature on kidney abnormalities associated with SARS-CoV-2 infection. Materials and methods: It was conducted a rapid review using the Cochrane methodology. Results: Pre-existing chronic kidney disease (CKD) in SARS-CoV-2 infected patients ranged from 1-38% and acute kidney injury (AKI) ranged from 2.9-86.4%. The prognosis of patients with SARS-CoV-2 infection was worse among those with CKD and those with normal remnant kidney function (RKF) that developed AKI. The risk of death was higher (pooled risk ratio =1.49; 95%CI: 1.09-2.04) among SARS-CoV-2 infected patients with pre-existing CKD. The RKF markers showed alterations among severe and non-surviving SARS-CoV-2 patients; the most common marker was serum creatinine. Conclusions: The scientific evidence shows the relevance of the evaluation and permanent monitoring of the RKF in SARS-CoV-2 hospitalized patients to improve the prognosis of those with pre-existing CKD as well as the prognosis of those without CKD who develop AKI.

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