Variaciones de la comunidad de copépodos plánticos en el gradiente estuarino-costero de Celestún,Yucatán, México

Zooplankton samples were collected monthly (from July 1994 to June 1995) to determine variations inabundance of planktonic copepods along the estuarine-coastal gradient in Celestun, Yucatan, México. From 17 copepod species, Acartia tonsa (51.8 %), A. lilljeborgii (12.2 %) and Pseudodiaptomus cokeri (30.8 %) were the most abundant species. Labidocera was the most diverse genus. Variation in species abundance was related mainly with gradients in salinity, temperature and biomass. The highest species richness was recorded in the mouth of the estuary due to a bigger exchange and mixture between the estuarine and marine fauna. The main features of the copepod community at Celestun are similar to those found in other regional coastal lagoons.Se efectuaron recolectas mensuales (julio de 1994 a junio de 1995) de zooplancton para determinar las variaciones de la abundancia de los copépodos pláncticos a través del gradiente estuarino-costero en Celestún, Yucatán. Se identificaron 17 especies de copépodos con Acartia tonsa (51.8 %), A. lilljeborgii (12.2 %) y Pseudodiaptomus cokeri (30.8 %) como las especies más abundantes, mientras que Labidocera fue el género más diverso. La variación en la abundancia de las especies se relacionó principalmente con los gradientes de temperatura, salinidad y biomasa zooplánctica . La mayor riqueza de especies se encontró en la boca del estero lo cual se debió a un mayor intercambio y mezcla de las faunas estuarina y marina. Las principales características de la comunidad de copépodos son similares a las encontradas en otras lagunas costeras de la región

Larvas de peces del litoral arrecifal del norte de Quintana Roo, Mar Caribe de México

Neuston samples (144) collected monthly from January to December 2004 from the north of the Mexican Caribbean Sea were analyzed. Trawlings were made at twelve sites along the coast, from Puerto Morelos to Cancun with a neuston net (0.60X 0.80 m; mesh 330µ) for 10 min., near surface. Salinity (spu), temperature (°C), and Oxygen (mg/l), were measured in situ, allowing the characterization of two climatic regimes: dry and wet season, and three environments: coastal (with oceanic characteristics), lagoon, and reef areas. A total of 5,577 fish larvae were captured (4,398.5 larvae/100 m3 ) corresponding to 55 families and 115 taxa. Gobies were the most conspicuous taxa, they were found in all three environments and ratify previous reports by other workers. Ctenogobius sp. (26.6%), Gobionellus sp.1 (17.9%), and Harengula jaguana (6.7%), made up more than 51%. Seasonally, highest average abundance was recorded in the dry season (56.9%) peaking in March (9.1±4.5 larvae/100 m3 ). The lagoon environment contained the lowest species richness (44) than the coastal (78) or reef (82) areas, but more larvae were caught (2,865.6 larvas/100 m3 ), a number higher than those collected at the other two environments put together.Se analizaron 144 muestras de neuston recolectadas mensualmente de enero a diciembre del 2004 en el Estado de Quintana Roo, Mar Caribe de México. Los arrastres se realizaron cerca de la superficie por 10 min., en 12 sitios de captura con una red de Neuston (0.60 X 0.80 m; malla 330 µm). Se registraron la temperatura (°C), salinidad (ups) y el oxígeno disuelto (mg/L), que permitieron caracterizar las condiciones hidrográficas de los lugares de muestreo. Se identificaron dos regímenes climáticos: secas y lluvias, y tres ambientes: costero (con características oceánicas), lagunar y arrecifal, cada uno con condiciones ambientales propias. Se capturaron un total de 5,577 larvas (4,398.5 larvas/100 m3 ) distribuidas en 55 familias y 115 taxa. La familia Gobiidae fue la más conspícua y se encontró en todos los ambientes, lo cual ratifica estudios previos de otros autores. Ctenogobius sp. (26.6%), Gobionellus sp. (17.9%) y Harengula jaguana (6.7%), sumaron más del 51% de las capturas. Temporalmente las mayores densidades promedio se encontraron en la época de secas (56.9%) con marzo como el mes de mayor abundancia (9.1±4.5 larvas/100 m3 ). El sistema Lagunar Nichupté presentó una menor riqueza de especies (42) que la zona costera (78) o arrecifal (82), pero en cambio, registró una abundancia (2,865.6 larvas/100 m3 ) inclusive mayor que los otros dos ambientes juntos

Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

Background Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories. Methods We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5–19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI <18·5 kg/m2) and obesity (BMI ≥30 kg/m2). For schoolaged children and adolescents, we report thinness (BMI <2 SD below the median of the WHO growth reference) and obesity (BMI >2 SD above the median). Findings From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining underweight or thinness. Interpretation The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesit

Diminishing benefits of urban living for children and adolescents’ growth and development

Optimal growth and development in childhood and adolescence is crucial for lifelong health and well-being1–6. Here we used data from 2,325 population-based studies, with measurements of height and weight from 71 million participants, to report the height and body-mass index (BMI) of children and adolescents aged 5–19 years on the basis of rural and urban place of residence in 200 countries and territories from 1990 to 2020. In 1990, children and adolescents residing in cities were taller than their rural counterparts in all but a few high-income countries. By 2020, the urban height advantage became smaller in most countries, and in many high-income western countries it reversed into a small urban-based disadvantage. The exception was for boys in most countries in sub-Saharan Africa and in some countries in Oceania, south Asia and the region of central Asia, Middle East and north Africa. In these countries, successive cohorts of boys from rural places either did not gain height or possibly became shorter, and hence fell further behind their urban peers. The difference between the age-standardized mean BMI of children in urban and rural areas was <1.1 kg m–2 in the vast majority of countries. Within this small range, BMI increased slightly more in cities than in rural areas, except in south Asia, sub-Saharan Africa and some countries in central and eastern Europe. Our results show that in much of the world, the growth and developmental advantages of living in cities have diminished in the twenty-first century, whereas in much of sub-Saharan Africa they have amplified

Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

Background: Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories. Methods: We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5-19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI &lt;18·5 kg/m2) and obesity (BMI ≥30 kg/m2). For school-aged children and adolescents, we report thinness (BMI &lt;2 SD below the median of the WHO growth reference) and obesity (BMI &gt;2 SD above the median). Findings: From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining underweight or thinness. Interpretation: The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesity. Funding: UK Medical Research Council, UK Research and Innovation (Research England), UK Research and Innovation (Innovate UK), and European Union