Efecto de incendios en la vegetación de sotobosque y propiedades químicas de suelo de bosques templados

Objective: to assess the severity of a forest fire and its impact on understory vegetation(shrubs, herbs, grasses) and on the chemical properties of the soil.Design/methodology/approach: in an area of 100 m 2 , individuals of shrubs, herbs andgrasses were recorded. Soil was also collected in 60 x 60 cm subsites in all samplingsites in three regions of a temperate forest considering the severity of the fire as intact,intermediate and severe.Results: it was found that the relative abundance of different life forms varied in relationto severity, only herbaceous benefited in intermediate severity, shrubs and grassesdecreased. Soil pH and exchangeable cations Mg++, Na+, K+ and Ca++ increased asfire severity increased. N, P, K nutrients increased mainly in the intermediate severity,contrary to expectations for N.Limitations of the study/implications: not having more temperate forest zonesreplicated reduces the ecological patterns of understory vegetation succession andchemical soil changes. Findings/conclusions: The intermediate fire severity presented greater abundance ofherbaceous plants. Similarly, the interchangeable cations, nitrogen, phosphorus andpotassium increased in the same severity.Objetivo: evaluar la severidad de un incendio forestal y su impacto en la vegetación de sotobosque (arbustos, hierbas, pastos) y en las propiedades químicas del suelo.Diseño/metodología/aproximación: en un área de 100 m 2 se registraron los individuos de arbustos, herbáceas y pastos. También se recolectó suelo en cuadros de 60 x 60 cm en todos los sitios de muestreo en tres regiones de un bosque templado considerando la severidad del incendio como intacto, intermedio y severo.Resultados: se encontró que la abundancia relativa de las diferentes formas de vida varió en relación a la severidad, solo las herbáceas se beneficiaron en severidades intermedias, los arbustos y pastos disminuyeron. El pH del suelo y los cationes intercambiables Mg ++ , Na + , K + y Ca ++ aumentaron conforme aumentó la severidad del incendio. Los nutrientes N, P, K aumentaron principalmente en las severidades intermedias, contrario a lo esperado para N.Limitaciones del estudio/implicaciones: no contar con réplicas de más zonas de bosques templados reduce los patrones ecológicos de la sucesión de la vegetación del sotobosque y los cambios químicos del suelo.Hallazgos/conclusiones: la severidad intermedia del incendio presento mayor abundancia de herbáceas. De igual manera, los cationes intercambiables, el nitrógeno, fósforo y potasio aumentaron en la misma en severidad

Familial hypercholesterolaemia in children and adolescents from 48 countries: a cross-sectional study

Background: Approximately 450 000 children are born with familial hypercholesterolaemia worldwide every year, yet only 2·1% of adults with familial hypercholesterolaemia were diagnosed before age 18 years via current diagnostic approaches, which are derived from observations in adults. We aimed to characterise children and adolescents with heterozygous familial hypercholesterolaemia (HeFH) and understand current approaches to the identification and management of familial hypercholesterolaemia to inform future public health strategies. Methods: For this cross-sectional study, we assessed children and adolescents younger than 18 years with a clinical or genetic diagnosis of HeFH at the time of entry into the Familial Hypercholesterolaemia Studies Collaboration (FHSC) registry between Oct 1, 2015, and Jan 31, 2021. Data in the registry were collected from 55 regional or national registries in 48 countries. Diagnoses relying on self-reported history of familial hypercholesterolaemia and suspected secondary hypercholesterolaemia were excluded from the registry; people with untreated LDL cholesterol (LDL-C) of at least 13·0 mmol/L were excluded from this study. Data were assessed overall and by WHO region, World Bank country income status, age, diagnostic criteria, and index-case status. The main outcome of this study was to assess current identification and management of children and adolescents with familial hypercholesterolaemia. Findings: Of 63 093 individuals in the FHSC registry, 11 848 (18·8%) were children or adolescents younger than 18 years with HeFH and were included in this study; 5756 (50·2%) of 11 476 included individuals were female and 5720 (49·8%) were male. Sex data were missing for 372 (3·1%) of 11 848 individuals. Median age at registry entry was 9·6 years (IQR 5·8-13·2). 10 099 (89·9%) of 11 235 included individuals had a final genetically confirmed diagnosis of familial hypercholesterolaemia and 1136 (10·1%) had a clinical diagnosis. Genetically confirmed diagnosis data or clinical diagnosis data were missing for 613 (5·2%) of 11 848 individuals. Genetic diagnosis was more common in children and adolescents from high-income countries (9427 [92·4%] of 10 202) than in children and adolescents from non-high-income countries (199 [48·0%] of 415). 3414 (31·6%) of 10 804 children or adolescents were index cases. Familial-hypercholesterolaemia-related physical signs, cardiovascular risk factors, and cardiovascular disease were uncommon, but were more common in non-high-income countries. 7557 (72·4%) of 10 428 included children or adolescents were not taking lipid-lowering medication (LLM) and had a median LDL-C of 5·00 mmol/L (IQR 4·05-6·08). Compared with genetic diagnosis, the use of unadapted clinical criteria intended for use in adults and reliant on more extreme phenotypes could result in 50-75% of children and adolescents with familial hypercholesterolaemia not being identified. Interpretation: Clinical characteristics observed in adults with familial hypercholesterolaemia are uncommon in children and adolescents with familial hypercholesterolaemia, hence detection in this age group relies on measurement of LDL-C and genetic confirmation. Where genetic testing is unavailable, increased availability and use of LDL-C measurements in the first few years of life could help reduce the current gap between prevalence and detection, enabling increased use of combination LLM to reach recommended LDL-C targets early in life

Total Organic Carbon Assessment in Soils Cultivated with Agave tequilana Weber in Jalisco, Mexico

The Agave tequilana Weber is an important commercial crop in the State of Jalisco, Mexico. However, the agave cultivation generates significant soil loss. For that reason, knowledge about the implementation of the agriculture management practices, such as manure application and the combination of inorganic fertilizers and manure, are relevant. The objective of this research was to determine the effect of agricultural management practices on the total organic carbon (TOC) in the soil in three study locations: Arandas, Tepatitlán, and Acatic in the Altos Sur region of Jalisco. A random sampling was carried out in each study location, 12 samples were obtained for each location at 0–30 cm deep, and a total of 36 samples were analyzed. The evaluated parameters were the potential hydrogen (pH), electrical conductivity (EC), bulk density (BD), soil-water saturation (SWS), total nitrogen (TN), and total organic carbon (TOC). Basic statistics and correlations between parameters were generated. In addition, to estimate TOC from a multivariate analysis, models were developed based on the lowest Akaike information criterion (AIC) and of the classification and regression trees (CART). ANOVA and Tukey test were determined. Results demonstrated a significant difference in the TOC percentages between the study locations. The Tukey test showed that there is no difference in TOC content between the Tepatitlán and Arandas sites, but there is a difference between these two sites and the Acatic. The latter resulted with the lowest values of TOC. Long-term studies are recommended to develop crop management strategies