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1.
Front Plant Sci ; 14: 1102340, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37223780

RESUMO

The high-elevation peatlands of the páramos of the northern Andes constitute a diverse environment that harbors large numbers of species and several types of plant communities along altitudinal, latitudinal, and environmental gradients. However, little is known about the structure and functioning of these ecosystems, including peatland vegetation types and their relative contribution to the production and accumulation of peat soils. In this paper we characterized the structure of peatland plant communities of the humid páramos of northern Ecuador by describing the distribution of plant growth-forms and their aboveground biomass patterns. Along an elevation gradient of 640 m we sampled vegetation in 16 peatlands and aboveground biomass in four peatlands. Three distinct peatland vegetation types were identified: High elevation Cushion peatlands, dominated by Plantago rigida and Distichia muscoides, Sedge and rush peatlands dominated by Carex spp. and Juncus spp., and Herbaceous and shrubby peatlands, with a more heterogenous and structurally complex vegetation. In terms of aboveground biomass, we found an 8-fold reduction in the higher peatlands compared to the lower sites, suggesting that the steep elevational gradients characteristic of Andean environments might be crucial in structuring the physiognomy and composition of peatland vegetation, either through its effects on temperature and other environmental factors, or through its effects on the age and development of soils. Additional studies are needed to evaluate the potential effects of temperature, hydrology, micro-topography, geological setting, and land-use, which are likely to influence vegetation patters in these peatlands.

2.
Forensic Sci Int ; 325: 110879, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34174769

RESUMO

Tsantsas are shrunken human heads originally made for ceremonial purposes by Amazonian indigenous groups of the Shuar and Achuar family, previously called Jivaroan tribes. A significant demand of these objects during the first half of the 20th century led to the manufacture of counterfeit shrunken heads for commercial purposes. For museums where these collections are held, as well as for the indigenous groups who claim their ownership, it is important to identify the origin and authenticity of these tsantsas. We hypothesized that a collection of 14 tsantsas from 3 different museum collections in Ecuador are human and aimed to characterize their sex and potential origin. We amplified the amelogenin gene and performed a high resolution melting analysis to determine their human origin and characterize their sex. We also analyzed a fragment (16209-16402) from the HVR-1 region to identify the mtDNA haplogroups present in the tsantsa collection. Our exploratory results show that all the tsantsas are human and that the collection is comprised of 13 males and 1 female. A total of seven mtDNA haplogroups were found among the tsantsa collection using the mtDNA EMPOP database. These results show a predominance of the Amerindian mtDNA haplogroups B, C and D. Additional principal component analysis, genetic distance tree and haplotype network analyses suggest a relationship between the tsantsa specimens and Native American groups.


Assuntos
Amelogenina/genética , DNA Mitocondrial/genética , Análise para Determinação do Sexo , Crânio , Antropologia Cultural/história , Equador , Etnicidade/genética , Feminino , Genética Forense , Haplótipos , História do Século XIX , História do Século XX , Humanos , Masculino , Museus
3.
Molecules ; 25(3)2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31991810

RESUMO

In the present work, a number of R-X⋯NH3 (X = Cl, Br, and I) halogen bonded systems were theoretical studied by means of DFT calculations performed at the ωB97XD/6-31+G(d,p) level of theory in order to get insights on the effect of the electron-donating or electron-withdrawing character of the different R substituent groups (R = halogen, methyl, partially fluorinated methyl, perfluoro-methyl, ethyl, vinyl, and acetyl) on the stability of the halogen bond. The results indicate that the relative stability of the halogen bond follows the Cl < Br < I trend considering the same R substituent whereas the more electron-withdrawing character of the R substituent the more stable the halogen bond. Refinement of the latter results, performed at the MP2/6-31+G(d,p) level showed that the DFT and the MP2 binding energies correlate remarkably well, suggesting that the Grimme's type dispersion-corrected functional produces reasonable structural and energetic features of halogen bond systems. DFT results were also observed to agree with more refined calculations performed at the CCSD(T) level. In a further stage, a more thorough analysis of the R-Br⋯NH3 complexes was performed by means of a novel electron localization/delocalization tool, defined in terms of an Information Theory, IT, based quantity obtained from the conditional pair density. For the latter, our in-house developed C++/CUDA program, called KLD (acronym of Kullback-Leibler divergence), was employed. KLD results mapped onto the one-electron density plotted at a 0.04 a.u. isovalue, showed that (i) as expected, the localized electron depletion of the Br sigma-hole is largely affected by the electron-withdrawing character of the R substituent group and (ii) the R-X bond is significantly polarized due to the presence of the NH3 molecule in the complexes. The afore-mentioned constitutes a clear indication of the dominant character of electrostatics on the stabilization of halogen bonds in agreement with a number of studies reported in the main literature. Finally, the cooperative effects on the [Br-CN]n system (n = 1-8) was evaluated at the MP2/6-31+G(d,p) level, where it was observed that an increase of about ~14.2% on the complex stability is obtained when going from n = 2 to n = 8. The latter results were corroborated by the analysis of the changes on the Fermi-hole localization pattern on the halogen bond zones, which suggests an also important contribution of the electron correlation in the stabilization of these systems.


Assuntos
Compostos de Amônio/química , Halogênios/química , Modelos Teóricos , Algoritmos , Elétrons , Modelos Moleculares , Eletricidade Estática
4.
Salud Publica Mex ; 54 Suppl 1: S42-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22965442

RESUMO

OBJECTIVE: In this evaluation we assess the quality of the general and clinical structure in medical units that deliver health services for the Medical Insurance for a New Generation (SMNG) enrollees. MATERIALS AND METHODS: The study population included 82 medical units that deliver health services to enrollees of the SMNG in 15 states of Mexico, during 2009. Two indexes: the general structure index and the clinical structure index were created. RESULTS: It was found an unequal quality of the general and clinical structure in the different levels of care. The results suggest that the first level of care lacks both important general and clinical structural items. They also show on average a regular quality in the second level of care and a good quality in the third level of care medical units. CONCLUSIONS: Our results support the main conclusion of the work of Bulatao, "Improving services requires moving beyond policy reform to strengthening implementation of services".


Assuntos
Seguro Saúde , Qualidade da Assistência à Saúde , Humanos , México
5.
Salud Publica Mex ; 54 Suppl 1: S50-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22965443

RESUMO

OBJECTIVE: To assess the quality of care provided at medical units that provide services to Medical Insurance for a New Generation (SMNG) enrollees. MATERIALS AND METHODS: The tracer methodology was used in a sample of 82 medical units selected in fifteen states of Mexico and data collected in November 2009. RESULTS: Problems were found to locate the minimal number of the 18 medical charts requested in three of the tracers. The first level of care on the average reports that the quality of the process of care is 6, in a 10 point scale. In the second level improves and the third level of care is better qualified. CONCLUSIONS: The tracer methodology has enabled us to assess the quality of care. There is room for improvement in the medical units of the state health services, to that end should be directed the efforts in the health system in Mexico.


Assuntos
Seguro Saúde , Garantia da Qualidade dos Cuidados de Saúde/métodos , Indicadores de Qualidade em Assistência à Saúde , Qualidade da Assistência à Saúde , Cobertura Universal do Seguro de Saúde , Pré-Escolar , Humanos , Lactente , México
6.
Salud pública Méx ; 54(supl.1): s42-s49, 2012. graf, tab
Artigo em Inglês | LILACS | ID: lil-647986

RESUMO

OBJECTIVE: In this evaluation we assess the quality of the general and clinical structure in medical units that deliver health services for the Medical Insurance for a New Generation (SMNG) enrollees. MATERIALS AND METHODS: The study population included 82 medical units that deliver health services to enrollees of the SMNG in 15 states of Mexico, during 2009. Two indexes: the general structure index and the clinical structure index were created. RESULTS: It was found an unequal quality of the general and clinical structure in the different levels of care. The results suggest that the first level of care lacks both important general and clinical structural items. They also show on average a regular quality in the second level of care and a good quality in the third level of care medical units. CONCLUSIONS: Our results support the main conclusion of the work of Bulatao, "Improving services requires moving beyond policy reform to strengthening implementation of services".


OBJETIVO: Se evalúa la calidad de la estructura física y clínica en las unidades médicas que proveen servicios de salud a los afiliados al Seguro Médico para una Nueva Generación (SMNG). MATERIALES Y MÉTODOS: La población de estudio incluyó 82 unidades médicas de los tres niveles de atención del SMNG en 15 estados de México, en 2009. Se elaboraron dos índices: el índice de estructura general y el índice de estructura clínica. RESULTADOS: Se encontró calidad variable en las unidades médicas. Los resultados sugieren que el primer nivel de atención tiene deficiencias en la estructura general y la estructura clínica. También se muestra una calidad regular en unidades de segundo y la mayor calidad en las de tercer nivel. CONCLUSIONES: nuestros resultados están en armonía con la conclusión de Bulatao: "la mejora de los servicios requiere moverse más allá de la reforma de las políticas, hacia la implementación de una estrategia de fortalecimiento de los servicios".


Assuntos
Humanos , Seguro Saúde , Qualidade da Assistência à Saúde , México
7.
Salud pública Méx ; 54(supl.1): s50-s56, 2012. tab
Artigo em Inglês | LILACS | ID: lil-647987

RESUMO

OBJECTIVE: To assess the quality of care provided at medical units that provide services to Medical Insurance for a New Generation (SMNG) enrollees. MATERIALS AND METHODS: The tracer methodology was used in a sample of 82 medical units selected in fifteen states of Mexico and data collected in November 2009. RESULTS: Problems were found to locate the minimal number of the 18 medical charts requested in three of the tracers. The first level of care on the average reports that the quality of the process of care is 6, in a 10 point scale. In the second level improves and the third level of care is better qualified. CONCLUSIONS: The tracer methodology has enabled us to assess the quality of care. There is room for improvement in the medical units of the state health services, to that end should be directed the efforts in the health system in Mexico.


OBJETIVO: Evaluar la calidad de la atención en unidades médicas que prestan servicios a afiliados al Seguro Médico para una Nueva Generación (SMNG). MATERIAL Y MÉTODOS: Se utilizó la metodología de trazadores en una muestra de 82 unidades médicas seleccionadas en quince estados de la República mexicana y los datos fueron recolectados en noviembre de 2009. RESULTADOS: En tres de los trazadores no se encontró el número de expedientes en las 18 unidades médicas. En el primer nivel de atención se reporta que la calidad del proceso de atención es de 6 en una escala de 0 a 10. La calidad mejora en el segundo nivel, y es la más alta en el tercer nivel. CONCLUSIONES: Se evaluó la calidad e identificaron oportunidades de mejora en la calidad de las unidades médicas del SMNG. Hacia ese objetivo deben ser dirigidos los esfuerzos en el sistema de salud en México.


Assuntos
Pré-Escolar , Humanos , Lactente , Seguro Saúde , Garantia da Qualidade dos Cuidados de Saúde/métodos , Indicadores de Qualidade em Assistência à Saúde , Qualidade da Assistência à Saúde , Cobertura Universal do Seguro de Saúde , México
8.
Cochabamba; UMSS-Fac. Agronomía. TESIS; 1991. 66 ; 28 cm p.
Tese em Espanhol | LIBOCS, LIBOSP | ID: biblio-1334739
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