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1.
Philos Trans A Math Phys Eng Sci ; 368(1913): 783-99, 2010 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-20083506

RESUMO

In this paper, I review to what extent we can understand the photometric properties of star clusters, and of low-mass, unresolved galaxies, in terms of population-synthesis models designed to describe 'simple stellar populations' (SSPs), i.e. groups of stars born at the same time, in the same volume of space and from a gas cloud of homogeneous chemical composition. The photometric properties predicted by these models do not readily match the observations of most star clusters, unless we properly take into account the expected variation in the number of stars occupying sparsely populated evolutionary stages, owing to stochastic fluctuations in the stellar initial mass function. In this case, population-synthesis models reproduce remarkably well the full ranges of observed integrated colours and absolute magnitudes of star clusters of various ages and metallicities. The disagreement between the model predictions and observations of cluster colours and magnitudes may indicate problems with or deficiencies in the modelling, and does not necessarily tell us that star clusters do not behave like SSPs. Matching the photometric properties of star clusters using SSP models is a necessary (but not sufficient) condition for clusters to be considered SSPs. Composite models, characterized by complex star-formation histories, also match the observed cluster colours.

2.
Col. med. estado Táchira ; 17(3): 22-26, jul.-sept. 2008. tab, graf
Artigo em Espanhol | LILACS | ID: lil-531272

RESUMO

Determinar factores de riesgo y modalidades diagnóstico-terapéuticas del Embarazo Ectópico (EE). Estudio descriptivo, analítico de 353 casos de EE. Período 2000-2006. Servicio de Gineco-obstetricia de IAHULA, Estado Mérida, Venezuela. 353 historias con diagnóstico de EE. Grupo predominante: 19-34 años (75,1 por ciento). Nuliparidad (25,5 por ciento). Antecedentes Gineco-obstétricos (27,2 por ciento); Anticonceptivos (45,3 por ciento); ITS (23, 2 por ciento); DIU (10,8 por ciento); Cirugía Ginecológica y/o Abdominal anterior (33,4 por ciento). ß-hCG positivas 94,3 por ciento; Culdocentesis positivas 78,16 por ciento. Hallazgo Ultrasonográfico: 88,33 por ciento, Hallazgo Quirúrgico: 310 casos; localización Tubarica (97,09 por ciento); Salpingectomía total: 84,1 por ciento. El EE es una emergencia obstétrica frecuente, pone en riesgo la vida de la paciente con patogénesis multifactorial.


Assuntos
Humanos , Adulto , Feminino , Gravidez , Gravidez Ectópica/diagnóstico , Infertilidade Feminina/história , Laparotomia/métodos , Ultrassom/efeitos adversos , Complicações na Gravidez/diagnóstico , Prontuários Médicos
3.
Familia ; 4(2): 4-5, 1992.
Artigo em Espanhol | MEDLINE | ID: mdl-12178188

RESUMO

PIP: Studies by WHO and the US National Research Council have concluded that early pregnancy is associated with elevated health risks for both the mother and infant. Adolescent pregnancy is a problem that should be confronted before the end of the century in the southern hemisphere, where the large majority of the population is comprised of young people. The International Medical Advisory Group of the IPPF has identified specific functions for programs directed to adolescents. Which should contribute to social development and prepare young people to understand and cope with the physical and emotional changes of adolescence and to make responsible decisions about sexuality and reproduction. A strategy for adolescent pregnancy prevention should include specific objectives. The adolescent should acquire adequate knowledge of human sexuality as part of integrated personality development. A more effective sex education program in the formal educational system could contribute to this goal. Efforts should be made to promote postponement of intercourse until a later age. A study in Atlanta, Georgia, indicated that such programs can succeed. Contraception should be easily accessible in adolescent clinics and elsewhere. Postcoital contraception should be available for occasional use. Venezuelan laws should be reviewed and legal barriers to contraception should be eliminated. At present, Ministry of Health facilities are prohibited from offering family planning (FP) services to minors unless they have previously been pregnant. Actions to meet these objectives include reinforcing the sex education curricula of primary and secondary schools, creating adolescent centers to channel the activities of young people and provide accessible health and FP services, and creating FP centers for young people where information and reliable and low cost contraception would be available. In 1991 PLAFAM, the Association for Family Planning, reached 4662 adolescents and their parents and teachers through its Services for Adolescents program. It contracted 39 institutions, gave 64 talks in educational centers, and held 3 workshops for students. An FP center exclusively for adolescents is planned for Caracas. A survey of fertility and contraceptive usage is badly needed. PLAFAM has initiated planning and the search for funding but as yet little interest has been shown by the Ministry of Health.^ieng


Assuntos
Serviços de Planejamento Familiar , Planejamento em Saúde , Filosofia , Gravidez na Adolescência , Educação Sexual , América , Demografia , Países em Desenvolvimento , Educação , Fertilidade , América Latina , Organização e Administração , População , Dinâmica Populacional , Comportamento Sexual , América do Sul , Venezuela
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