Madera juvenil en Populus deltoides 'Stoneville 67': análisis de la variación de la densidad en el fuste / Juvenile wood in Populus deltoides 'Stoneville 67': analysis of density variation in the stem

Resumen El objetivo del presente trabajo fue determinar la edad de transición de madera juvenil a madura a partir del estudio de la variación axial y radial de la densidad y realizar modelos descriptivos de distribución de madera juvenil y madura en el fuste de Populus deltoides, clon 'Stoneville 67' de 20 años de edad. La densidad presentó un aumento de sus valores de médula a corteza y desde la base hacia el ápice. La edad de transición se determinó entre los 10-12 años de edad, el volumen de madera juvenil y madura fue del 40 % y 60 % respectivamente. La distribución de la madera juvenil coincidió con el modelo de cilindro central.

Abstract The objective of the present work was to determine the age of transition from juvenile to mature wood from the study of the axial and radial variation of density and to carry out descriptive models of distribution of juvenile and mature wood in the stem of Populus deltoides, clone 'Stoneville 67' of 20 years of age. The density presented an increase in its values ​​from the medulla to the cortex and from the base to the apex. The transition age was determined between 10-12 years of age, the volume of juvenile and mature wood was 40% and 60%, respectively. The distribution of juvenile wood coincided with the central cylinder model.

Using government data to understand the use and availability of medicines for hypertension and diabetes: lessons from Peru.

BACKGROUND: Regular measurement of the availability and use of key medicines for non-communicable diseases allows the tracking of progress to achieve equitable access to medicines. Using a country-level public sector monitoring system for medicine supply, we aim to evaluate the availability and use of losartan 50 mg tablets and metformin 850 mg tablets between 2015 and 2020 investigating the impact of different policy changes and the COVID-19 pandemic. METHODS: Data from the Peruvian National System of Medicine Supply were analyzed using an interrupted time series analysis with known and unknown structural breaks. The outcomes assessed were medicine use (monthly doses dispensed at facilities over time) and medicine availability (proportion of facilities that reported having the medicine available). RESULTS: The use of losartan and metformin at the primary level of care had a linear increasing trend over the period of analysis. In secondary and tertiary levels of care, there were no increases but some significant level and trend changes of doses dispensed at different times between 2017 to 2019, but none were related to the change of procurement procedures. At all levels of care, the COVID-19 onset in April 2020 caused an abrupt drop in doses dispensed especially at the primary level. Regarding availability, we found an increasing linear trend in the primary level of care for both medicines. In secondary and tertiary levels of care, the availability fluctuated between 40 and 95%. The onset of the COVID-19 pandemic did not significantly impact medicine availability, except for losartan in the tertiary level of care. CONCLUSION: The availability and proper dispensing of first-line medicines for hypertension and diabetes is an essential factor for sustainable and equitable treatment. Health care systems need to be prepared for forecasting the increasing demand of medicines for chronic diseases, but also to maintain effective medicine supply chains during humanitarian crisis like pandemics.

Use of Interrupted Time Series Analysis in Understanding the Course of the Congenital Syphilis Epidemic in Brazil.

Background: To fight against the rising incidence of syphilis, the Brazilian Ministry of Health (MoH) launched the "Syphilis No!" Project (SNP), with specific resources funded by a parliamentary amendment. Then, in 2018, a national rapid response started to be implemented on the Brazilian Unified Health System (SUS, Sistema Único de Saúde) in two strategic lines (1) to reinforce SUS's universal actions and (2) to implement specific ones to 100 municipalities chosen by the MoH as priorities for syphilis congenital response. In 2015, such localities represented 6895% of congenital syphilis cases in Brazil. In this context, SNP has implemented actions to strengthen epidemiological surveillance of acquired syphilis and congenital syphilis by instituting an integrated and collaborative response through health services networks and reinforcing interstate relations. Methods: A quasi-experimental study using time series analysis was conducted to assess immediate impacts and changes to the trend in national congenital syphilis before and after the project, from September 2016 to December 2019. Data were assessed considering rates of congenital syphilis per 1,000 live births in all priority municipalities (n=100) covered by the project and in non-priority municipalities (n=5,470) from all five macro-regions of Brazil. Findings: Priority municipalities showed a greater reduction (change in trend) in comparison to non-priority. The linear regression model revealed trend changes after the intervention, with both groups of municipalities showing a drop in the average monthly number of cases per 1,000 live births, with a reduction of -0·21 (CI 95% -0·33 to -0·09; p=0·0011) in priority municipalities and of -0·10 (CI 95% -0.19 to -0.02; p=0·0216) in non-priority municipalities. Interpretation: The study using ITS provides important evidence on the direction, timing, and magnitude of the effects of interventions introduced as part of the SNP on congenital syphilis in Brazil. Our results suggest that the Syphilis No! Project influenced the trends of congenital syphilis in Brazil from 2018, with higher reductions achieved in the priority municipalities. Funding: The research is funded by a grant to the Syphilis No! Project from Brazilian Ministry of Health (Project Number: 54/2017). The funders had no role in study design, analysis, decision to publish, or preparation of the manuscript.

Regression models to stratify the copper toxicity responses and tolerance mechanisms of Glycine max (L.) Merr. plants.

MAIN CONCLUSION: Root antioxidant defense, restricted root-to-shoot Cu translocation, altered nutrient partition, and leaf gas exchange adjustments occurred as tolerance mechanisms of soybean plants to increasing soil Cu levels. The intensive application of copper (Cu) fungicides has been related to the accumulation of this metal in agricultural soils. This study aimed to evaluate the effects of increasing soil Cu levels on soybean (Glycine max) plants. Soybean was cultivated under greenhouse conditions in soils containing different Cu concentrations (11.2, 52.3, 79.4, 133.5, 164.0, 205.1, or 243.8 mg kg-1), and biochemical and morphophysiological plant responses were analyzed through linear and nonlinear regression models. Although Cu concentrations around 50 mg kg-1 promoted some positive effects on the initial development of soybean plants (e.g., increased root length and dry weight), these Cu concentrations also induced root oxidative stress and activated defense mechanisms (such as the induction of antioxidant response, N and S accumulation in the roots). At higher concentrations, Cu led to growth inhibition (mainly of the root), nutritional imbalance, and damage to the photosynthetic apparatus of soybean plants, resulting in decreased CO2 assimilation and stomatal conductance. In contrast, low translocation of Cu to the leaves, conservative water use, and increased carboxylation efficiency contributed to the partial mitigation of Cu-induced stress. These responses allowed soybean plants treated with Cu levels in the soil as high as 90 mg kg-1 to maintain growth parameters higher than or similar to those of plants in the non-contaminated soil. These data provide a warning for the potentially deleterious consequences of the increasing use of Cu-based fungicides. However, it is necessary to verify how the responses to Cu contamination are affected by different types of soil and soybean cultivars.

Dose-Dependent Dual Effect of Soil Copper on the Initial Development of Glycine max (L.) Merr. cv. BRS 257 Seedlings.

The aim of this study was to evaluate, through nonlinear regression models, the initial development of soybean (Glycine max L. Merr. cv. BRS 257) in soil supplemented with different copper levels. The experiment was performed in a greenhouse under natural light and temperature conditions. The seeds were sowed in soil containing different copper levels (11.20, 32.28, 52.31, 64.51, 79.42, 117.70, 133.53, 144.32, or 164.00 mg kg- 1). Germination percentage was not affected by the increase of copper content in the soil, but there was a delay in the germination process. There was no influence of copper levels on the seedling emergence speed index until 98.42 mg kg- 1; however, higher copper amounts reduced this parameter. Low copper concentrations increased plant development, but higher concentrations compromised mainly root growth. Overall, these results suggest that copper supplementation in the soil exerted dose-dependent dual effects on soybean seedlings.

Segmented regression analysis of interrupted time series data to assess outcomes of a South American road traffic alcohol policy change.

BACKGROUND: In Chile, a new law introduced in March 2012 decreased the legal blood alcohol concentration (BAC) limit for driving while impaired from 1 to 0.8 g/l and the legal BAC limit for driving under the influence of alcohol from 0.5 to 0.3 g/l. The goal is to assess the impact of this new law on mortality and morbidity outcomes in Chile. METHODS: A review of national databases in Chile was conducted from January 2003 to December 2014. Segmented regression analysis of interrupted time series was used for analyzing the data. In a series of multivariable linear regression models, the change in intercept and slope in the monthly incidence rate of traffic deaths and injuries and association with alcohol per 100,000 inhabitants was estimated from pre-intervention to postintervention, while controlling for secular changes. In nested regression models, potential confounding seasonal effects were accounted for. All analyses were performed at a two-sided significance level of 0.05. RESULTS: Immediate level drops in all the monthly rates were observed after the law from the end of the prelaw period in the majority of models and in all the de-seasonalized models, although statistical significance was reached only in the model for injures related to alcohol. After the law, the estimated monthly rate dropped abruptly by -0.869 for injuries related to alcohol and by -0.859 adjusting for seasonality (P < 0.001). Regarding the postlaw long-term trends, it was evidenced a steeper decreasing trend after the law in the models for deaths related to alcohol, although these differences were not statistically significant. CONCLUSIONS: A strong evidence of a reduction in traffic injuries related to alcohol was found following the law in Chile. Although insufficient evidence was found of a statistically significant effect for the beneficial effects seen on deaths and overall injuries, potential clinically important effects cannot be ruled out.

Inflection and stability points of diphasic logistic analysis of growth

Growth functions with inflection points following a diphasic model, can be adjusted by two approaches using segmented regression or the sum of two functions. In both cases, there are two functions, one for each phase, with inflection and stability points. However, when they are summed, the result is a new function and the points of inflection and stability are different from those obtained from using each function individually. A method to determine these points in a diphasic logistics sum of functions is suggested and the results obtained from fitting the models to eucalyptus growth data showed a better fit of the logistic diphasic sum as compared with segmented regression and monophasic logistic models.(AU)

Inflection and stability points of diphasic logistic analysis of growth

Growth functions with inflection points following a diphasic model, can be adjusted by two approaches using segmented regression or the sum of two functions. In both cases, there are two functions, one for each phase, with inflection and stability points. However, when they are summed, the result is a new function and the points of inflection and stability are different from those obtained from using each function individually. A method to determine these points in a diphasic logistics sum of functions is suggested and the results obtained from fitting the models to eucalyptus growth data showed a better fit of the logistic diphasic sum as compared with segmented regression and monophasic logistic models.

Modelos de regressão com platô na estimativa do tamanho de parcelas em experimento de conservação in vitro de maracujazeiro / Using of regression plateau models in estimation of plot sizes for experiments with passion fruit

A determinação do tamanho de parcela é uma prática pertinente ao planejamento experimental e sua caracterização otimizada, em conjunto com o controle do material experimental, permite a obtenção de resultados com maior precisão e qualidade. Neste trabalho, determinou-se o tamanho de parcelas para experimentos de conservação in vitro de maracujazeiro, em dez ensaios de uniformidade com a espécie Passiflora Giberti N. E. Brown, utilizando-se o modelo de regressão linear segmentado com platô e o modelo de regressão quadrática segmentado com platô, que utilizam a técnica de resposta com platô a modelos que possuam mínimo. Os ensaios de uniformidade foram oriundos de experimento conduzido no delineamento inteiramente casualizado, com 20 unidades básicas (ub), e os tratamentos dispostos em esquema fatorial com três concentrações de sacarose, três concentrações de sorbitol e uma testemunha. A coleta dos dados foi realizada aos 60 dias após a incubação, medindo-se o comprimento das brotações. Os tamanhos de parcelas variaram com o método utilizado, encontrando-se parcelas formadas por seis explantes pelo modelo da regressão linear segmentado com platô e de dez explantes pelo modelo de regressão quadrática segmentado com platô.

The determination of the plot size is a practical question to the experimental design, and its characterization in an optimized way allows obtaining larger precision and quality results. This research aimed to determine the plot size in experiments in vitro that seek the passion fruit plant conservation in ten uniformity assays with the species Passiflora Giberti N. E. Brown. The tests of uniformity came from an experiment conducted in a completely randomized design with treatments in a factorial design with three concentrations of sucrose, three concentrations of sorbitol and a control. Each treatment was considered as a uniformity assay, with 20 basic units. The evaluations of the experiments were done in the 60 days of incubation, being measured the shoots' length. For the estimate of the optimal plot size it was used the models segmented with linear- plateau, and the quadratic-plateau. The plot size varied with the method used, with values from 6 basic units for the linear-plateau model segmented, and from 10 basic units, for quadratic-plateau model.

Modelos de regressão com platô na estimativa do tamanho de parcelas em experimento de conservação in vitro de maracujazeiro

The determination of the plot size is a practical question to the experimental design, and its characterization in an optimized way allows obtaining larger precision and quality results. This research aimed to determine the plot size in experiments in vitro that seek the passion fruit plant conservation in ten uniformity assays with the species Passiflora Giberti N. E. Brown. The tests of uniformity came from an experiment conducted in a completely randomized design with treatments in a factorial design with three concentrations of sucrose, three concentrations of sorbitol and a control. Each treatment was considered as a uniformity assay, with 20 basic units. The evaluations of the experiments were done in the 60 days of incubation, being measured the shoots' length. For the estimate of the optimal plot size it was used the models segmented with linear- plateau, and the quadratic-plateau. The plot size varied with the method used, with values from 6 basic units for the linear-plateau model segmented, and from 10 basic units, for quadratic-plateau model.

A determinação do tamanho de parcela é uma prática pertinente ao planejamento experimental e sua caracterização otimizada, em conjunto com o controle do material experimental, permite a obtenção de resultados com maior precisão e qualidade. Neste trabalho, determinou-se o tamanho de parcelas para experimentos de conservação in vitro de maracujazeiro, em dez ensaios de uniformidade com a espécie Passiflora Giberti N. E. Brown, utilizando-se o modelo de regressão linear segmentado com platô e o modelo de regressão quadrática segmentado com platô, que utilizam a técnica de resposta com platô a modelos que possuam mínimo. Os ensaios de uniformidade foram oriundos de experimento conduzido no delineamento inteiramente casualizado, com 20 unidades básicas (ub), e os tratamentos dispostos em esquema fatorial com três concentrações de sacarose, três concentrações de sorbitol e uma testemunha. A coleta dos dados foi realizada aos 60 dias após a incubação, medindo-se o comprimento das brotações. Os tamanhos de parcelas variaram com o método utilizado, encontrando-se parcelas formadas por seis explantes pelo modelo da regressão linear segmentado com platô e de dez explantes pelo modelo de regressão quadrática segmentado com platô.

Modelos de regressão com platô na estimativa do tamanho de parcelas em experimento de conservação in vitro de maracujazeiro

The determination of the plot size is a practical question to the experimental design, and its characterization in an optimized way allows obtaining larger precision and quality results. This research aimed to determine the plot size in experiments in vitro that seek the passion fruit plant conservation in ten uniformity assays with the species Passiflora Giberti N. E. Brown. The tests of uniformity came from an experiment conducted in a completely randomized design with treatments in a factorial design with three concentrations of sucrose, three concentrations of sorbitol and a control. Each treatment was considered as a uniformity assay, with 20 basic units. The evaluations of the experiments were done in the 60 days of incubation, being measured the shoots' length. For the estimate of the optimal plot size it was used the models segmented with linear- plateau, and the quadratic-plateau. The plot size varied with the method used, with values from 6 basic units for the linear-plateau model segmented, and from 10 basic units, for quadratic-plateau model.

A determinação do tamanho de parcela é uma prática pertinente ao planejamento experimental e sua caracterização otimizada, em conjunto com o controle do material experimental, permite a obtenção de resultados com maior precisão e qualidade. Neste trabalho, determinou-se o tamanho de parcelas para experimentos de conservação in vitro de maracujazeiro, em dez ensaios de uniformidade com a espécie Passiflora Giberti N. E. Brown, utilizando-se o modelo de regressão linear segmentado com platô e o modelo de regressão quadrática segmentado com platô, que utilizam a técnica de resposta com platô a modelos que possuam mínimo. Os ensaios de uniformidade foram oriundos de experimento conduzido no delineamento inteiramente casualizado, com 20 unidades básicas (ub), e os tratamentos dispostos em esquema fatorial com três concentrações de sacarose, três concentrações de sorbitol e uma testemunha. A coleta dos dados foi realizada aos 60 dias após a incubação, medindo-se o comprimento das brotações. Os tamanhos de parcelas variaram com o método utilizado, encontrando-se parcelas formadas por seis explantes pelo modelo da regressão linear segmentado com platô e de dez explantes pelo modelo de regressão quadrática segmentado com platô.

Implicações da aplicação de fungicida na adaptabilidade e estabilidade de rendimento de grãos em aveia branca

Twenty oat genotypes (Avena sativa L.) tested in thirteen environments were submitted to adaptability and stability analyses aiming at evaluating the effects of fungicide utilization following the segmented regression model of CRUZ et al. (1989). Fungicide application affected the parameters of adaptability (b1), responsiveness (b1 + b²) and stability ( img border=0 id="_x0000_i1028" src="../../../../img/revistas/cr/v34n3/a07img01.jpg">) indicating that estimatives must be performed individually in environments with and without fungicide. Fungicide application had a favorable effect on the stability of grain yield, inasmuch as four of the tested genotypes were shown to be stable (UPF 19, UPF 20, OR-3 e OR-4); however, all genotypes revealed instability of grain yield in the absence of fungicide. No tested cultivar showed characteristics of the ideal genotype, as predicted by the adopted model.

Vinte genótipos de aveia (Avena sativa L.), testados em 13 ambientes, foram submetidos à análise de adaptabilidade e estabilidade com o objetivo de avaliar o efeito da utilização de fungicida nestes parâmetros, através do modelo de regressão segmentado de CRUZ et al. (1989). A aplicação de fungicida afetou os parâmetros de adaptabilidade (b1), responsividade (b1+b2) e estabilidade ( img border=0 id="_x0000_i1026" src="../../../../img/revistas/cr/v34n3/a07img01.jpg">), indicando que as estimativas devam ser realizadas em separado nos ambientes com e sem fungicida. Além disso, o uso de fungicida proporcionou efeito favorável sobre a estabilidade de rendimento de grãos, sendo que quatro genótipos testados mostraram ser estáveis (UPF 19, UPF 20, OR-3 e OR-4), enquanto que na ausência de fungicida todos os genótipos revelaram instabilidade de rendimento de grãos. Entretanto, nenhuma cultivar testada evidenciou características de genótipo ideal, conforme preconizado pelo modelo adotado.