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1.
J Fish Biol ; 102(5): 1017-1028, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36794454

RESUMEN

Functional morphology investigates the relationships between morphological characters and external factors, such as environmental, physical and ecological features. Here, we evaluate the functional relationships between body shape and trophic ecology of a tropical demersal marine fish community using geometric morphometrics techniques and modelling, hypothesizing that shape variables could partially explain fish trophic level. Fish were collected over the continental shelf of northeast Brazil (4-9°S). Analysed fish were distributed into 14 orders, 34 families and 72 species. Each individual was photographed in lateral view, and 18 landmarks were distributed along the body. A principal component analysis (PCA) applied on morphometric indices revealed that fish body elongation and fin base shape were the main axes of variation explaining the morphology. Low trophic levels (herbivore and omnivore) are characterized by deep bodies and longer dorsal and anal fin bases, while predators present elongated bodies and narrow fin bases. Fin position (dorsal and anal fins) on the fish body is another important factor contributing to (i) body stability at high velocity (top predators) or (ii) manoeuvrability (low trophic levels). Using multiple linear regression, we verified that 46% of trophic level variability could be explained by morphometric variables, with trophic level increasing with body elongation and size. Interestingly, intermediate trophic categories (e.g., low predators) presented morphological divergence for a given trophic level. Our results, which can likely be expanded to other tropical and nontropical systems, show that morphometric approaches can provide important insights into fish functional characteristics, especially in trophic ecology.


Asunto(s)
Peces , Somatotipos , Animales , Brasil
2.
Molecules ; 25(6)2020 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-32213848

RESUMEN

Several previous studies on targeted food items using carbon and nitrogen stable isotope ratios in Brazil have revealed that many of the items investigated are adulterated; mislabeled or even fraud. Here, we present the first Brazilian isotopic baseline assessment that can be used not only in future forensic cases involving food authenticity, but also in human forensic anthropology studies. The δ13C and δ15N were determined in 1245 food items and 374 beverages; most of them made in Brazil. The average δ13C and δ15N of C3 plants were -26.7 ± 1.5‱, and 3.9 ± 3.9‱, respectively, while the average δ13C and δ15N of C4 plants were -11.5 ± 0.8‱ and 4.6 ± 2.6‱, respectively. The δ13C and δ15N of plant-based processed foods were -21.8 ± 4.8‱ and 3.9 ± 2.7‱, respectively. The average δ13C and δ15N of meat, including beef, poultry, pork and lamb were -16.6 ± 4.7‱, and 5.2 ± 2.6‱, respectively, while the δ13C and δ15N of animal-based processed foods were -17.9 ± 3.3‱ and 3.3 ± 3.5‱, respectively. The average δ13C of beverages, including beer and wine was -22.5 ± 3.1‱. We verified that C-C4 constitutes a large proportion of fresh meat, dairy products, as well as animal and plant-based processed foods. The reasons behind this high proportion will be addressed in this study.


Asunto(s)
Isótopos de Carbono/análisis , Isótopos de Nitrógeno/análisis , Animales , Bebidas/análisis , Brasil , Bovinos , Productos Lácteos/análisis , Aves de Corral , Ovinos , Vino/análisis
3.
Sci Total Environ ; 715: 136601, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32041036

RESUMEN

Solar radiation in general and UV radiation in particular have been recognized to stimulate plant litter decomposition through photochemical mineralization of organic molecules such as lignin and through facilitation of microbial decomposition in dryland ecosystems. However, little is known about how photodegradation may influence decomposition in other ecosystems not subject to moisture limitations and under what conditions photodegradation may be favored. Decomposition in humid tropical ecosystems is a complex process, and it can be influenced by a number of environmental factors that are distinct from arid and semi-arid ecosystems. To assess the mechanisms underlying photodegradation by ultraviolet B (UV-B) radiation in a humid tropical ecosystem, we designed a 300-day field experiment in a tropical site in Brazil with high levels of annual precipitation, compared to arid ecosystems, and exposed litter to three levels of radiation (full sun, UV-B removed, and shade) combined with a biocide treatment. Results show that after nearly one year of exposure, the microbial biomass was not affected by UV-B incidence, and this effect has not yet been fully understood for tropical ecosystems. Modeled using an exponential deceleration equation, the removal of UV-B radiation decelerated the plant litter decomposition rate for the control conditions by 21% compared to litter exposed to full sun. Interestingly, shaded litter exhibited similar mass loss compared to litter exposed to full sun. Furthermore, differences in the decay constant among radiation treatments due to the UV-B effect were independent of lignin loss. Overall, our study suggests that UV-B radiation contributed to plant litter decomposition through carbon losses but had no discernible effect on nitrogen, lignin, or cellulose loss specifically. Importantly, our results demonstrate that photodegradation occurs under humid tropical conditions, and further studies are necessary to examine the mechanisms of carbon loss.


Asunto(s)
Ecosistema , Hojas de la Planta , Brasil , Fotólisis , Plantas
4.
Am J Hum Biol ; 23(5): 642-50, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21630371

RESUMEN

OBJECTIVES: Amazonian populations are experiencing dietary changes characteristic of the nutrition transition. However, the degree of change appears to vary between urban and rural settings. To investigate this process, we determined carbon and nitrogen stable isotope ratios in fingernails and dietary intake of Amazonian populations living along a rural to urban continuum along the Solimões River in Brazil. METHODS: Carbon and nitrogen stable isotope ratios were analyzed from the fingernails of 431 volunteer subjects living in different settings ranging from rural villages, small towns to urban centers along the Solimões River. Data from 200 dietary intake surveys were also collected using food frequency questionnaires and 24-h recall interviews in an effort to determine qualitative aspects of diet composition. RESULTS: Fingernail δ(13) C values (mean ± standard deviation) were -23.2 ± 1.3, -20.2 ± 1.5, and -17.4 ± 1.3‰ and δ(15) N values were 11.8 ± 0.6, 10.4 ± 0.8, and 10.8 ± 0.7‰ for those living in rural villages, small towns, and major cities, respectively. We found a gradual increase in the number of food items derived from C(4) plant types (meat and sugar) and the replacement of food items derived from C(3) plant types (fish and manioc flour) with increasing size of urban centers. CONCLUSION: Increasing urbanization in the Brazilian Amazon is associated with a significant change in food habits with processed and industrialized products playing an increasingly important role in the diet and contributing to the nutrition transition in the region.


Asunto(s)
Isótopos de Carbono/análisis , Dieta , Conducta Alimentaria , Marcaje Isotópico/métodos , Isótopos de Nitrógeno/análisis , Urbanización , Adulto , Brasil , Análisis de los Alimentos/métodos , Humanos , Queratinas/análisis , Uñas/química , Población Rural , Encuestas y Cuestionarios , Población Urbana
5.
Ecol Evol ; 1(3): 421-34, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22393511

RESUMEN

We estimated carbon and nitrogen stocks in aboveground biomass (AGB) and belowground biomass (BGB) along an elevation range in forest sites located on the steep slopes of the Serra do Mar on the north coast of the State of São Paulo, southeast Brazil. In elevations of 100 m (lowland), 400 m (submontane), and 1000 m (montane) four 1-ha plots were established, and above- (live and dead) and belowground (live and dead) biomass were determined. Carbon and nitrogen concentrations in each compartment were determined and used to convert biomass into carbon and nitrogen stocks. The carbon aboveground stock (C(AGB)) varied along the elevation range from approximately 110 to 150 Mg·ha(-1), and nitrogen aboveground stock (N(AGB)), varied from approximately 1.0 to 1.9 Mg·ha(-1). The carbon belowground stock (C(BGB)) and the nitrogen belowground stock (N(BGB)) were significantly higher than the AGB and varied along the elevation range from approximately 200-300 Mg·ha(-1), and from 14 to 20 Mg·ha(-1), respectively. Finally, the total carbon stock (C(TOTAL)) varied from approximately 320 to 460 Mg·ha(-1), and the nitrogen total stock (N(TOTAL)) from approximately 15 to 22 Mg·ha(-1). Most of the carbon and nitrogen stocks were found belowground and not aboveground as normally found in lowland tropical forests. The above- and belowground stocks, and consequently, the total stocks of carbon and nitrogen increased significantly with elevation. As the soil and air temperature also decreased significantly with elevation, we found a significantly inverse relationship between carbon and nitrogen stocks and temperature. Using this inverse relationship, we made a first approach estimate that an increase of 1°C in soil temperature would decrease the carbon and nitrogen stocks in approximately 17 Mg·ha(-1) and 1 Mg·ha(-1) of carbon and nitrogen, respectively.

6.
Cad. saúde pública ; 25(12): 2612-2620, dez. 2009. ilus, tab
Artículo en Portugués | LILACS | ID: lil-538399

RESUMEN

O estudo analisa a confiabilidade dos dados relativos ao cumprimento da Emenda Constitucional nº. 29 (EC29) declarados ao Sistema de Informações sobre Orçamentos Públicos em Saúde (SIOPS) pelos municípios de Pernambuco, Brasil. Configura-se como um estudo quantitativo, do tipo transversal e de caráter analítico, tendo como referência o período de 2000 a 2005. Os demonstrativos contábeis auditados pelo Tribunal de Contas do Estado (TCE) foram tomados como parâmetro para verificar a confiabilidade dos percentuais de aplicação da EC29 declarados ao SIOPS, sendo utilizado o coeficiente de correlação intraclasses (CCI) como prova estatística na medição da concordância dos dados. Os resultados demonstram a dissonância existente entre as bases consultadas, sugerindo um nível de concordância discreto a moderado entre os dados do SIOPS e do TCE. A baixa concordância identificada pode ser decorrente da falta de consenso pelos municípios acerca da composição das receitas e despesas vinculadas à saúde ou da existência de critérios diferentes no cálculo da EC29 entre o SIOPS e a auditoria do TCE.


The present study analyzes the reliability of data on compliance with Constitutional Amendment 29 (CA29) reported to the Public Healthcare Budget Information System (known as SIOPS) by municipalities in the State of Pernambuco, Brazil. A quantitative, analytical cross-sectional study was conducted using the years 2000 to 2005 as the reference. Invoices audited by the State Accounts Court were used as the parameter for determining reliability of the percentage of compliance with CA29 as reported to SIOPS, using the intraclass correlation coefficient (ICC) to measure data agreement. The results show a mismatch between the databases, suggesting slight to moderate agreement between the SIOPS data and those from the State Accounts Court. The low degree of agreement may result from lack of consensus among municipalities regarding definition of health-related revenues and expenses or the existence of different criteria used by SIOPS and the State Accounts Court for calculating the CA29.


Asunto(s)
Humanos , Presupuestos/legislación & jurisprudencia , Atención a la Salud/legislación & jurisprudencia , Financiación Gubernamental/legislación & jurisprudencia , Sistemas de Información/legislación & jurisprudencia , Brasil , Estudios Transversales , Atención a la Salud/organización & administración , Gobierno Federal , Financiación Gubernamental/economía , Gastos en Salud/legislación & jurisprudencia , Sistemas de Información/normas , Sector Público
7.
Cad Saude Publica ; 25(12): 2612-20, 2009 Dec.
Artículo en Portugués | MEDLINE | ID: mdl-20191152

RESUMEN

The present study analyzes the reliability of data on compliance with Constitutional Amendment 29 (CA29) reported to the Public Healthcare Budget Information System (known as SIOPS) by municipalities in the State of Pernambuco, Brazil. A quantitative, analytical cross-sectional study was conducted using the years 2000 to 2005 as the reference. Invoices audited by the State Accounts Court were used as the parameter for determining reliability of the percentage of compliance with CA29 as reported to SIOPS, using the intraclass correlation coefficient (ICC) to measure data agreement. The results show a mismatch between the databases, suggesting slight to moderate agreement between the SIOPS data and those from the State Accounts Court. The low degree of agreement may result from lack of consensus among municipalities regarding definition of health-related revenues and expenses or the existence of different criteria used by SIOPS and the State Accounts Court for calculating the CA29.


Asunto(s)
Presupuestos/legislación & jurisprudencia , Atención a la Salud/legislación & jurisprudencia , Financiación Gubernamental/legislación & jurisprudencia , Sistemas de Información/legislación & jurisprudencia , Brasil , Estudios Transversales , Atención a la Salud/organización & administración , Gobierno Federal , Financiación Gubernamental/economía , Gastos en Salud/legislación & jurisprudencia , Humanos , Sistemas de Información/normas , Sector Público
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