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1.
Am J Bot ; 109(11): 1918-1938, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36380502

RESUMEN

PREMISE: Evolution of separate sexes from hermaphroditism often proceeds through gynodioecy, but genetic constraints on this process are poorly understood. Genetic (co-)variances and between-sex genetic correlations were used to predict evolutionary responses of multiple reproductive traits in a sexually dimorphic gynodioecious species, and predictions were compared with observed responses to artificial selection. METHODS: Schiedea (Caryophyllaceae) is an endemic Hawaiian lineage with hermaphroditic, gynodioecious, subdioecious, and dioecious species. We measured genetic parameters of Schiedea salicaria and used them to predict evolutionary responses of 18 traits in hermaphrodites and females in response to artificial selection for increased male (stamen) biomass in hermaphrodites or increased female (carpel, capsule) biomass in females. Observed responses over two generations were compared with predictions in replicate lines of treatments and controls. RESULTS: In only two generations, both stamen biomass in hermaphrodites and female biomass in females responded markedly to direct selection, supporting a key assumption of models for evolution of dioecy. Other biomass traits, pollen and ovule numbers, and inflorescence characters important in wind pollination evolved indirectly in response to selection on sex allocation. Responses generally followed predictions from multivariate selection models, with some responses unexpectedly large due to increased genetic correlations as selection proceeded. CONCLUSIONS: Results illustrate the power of artificial selection and utility of multivariate selection models incorporating sex differences. They further indicate that pollen and ovule numbers and inflorescence architecture could evolve in response to selection on biomass allocation to male versus female function, producing complex changes in plant phenotype as separate sexes evolve.


Asunto(s)
Caryophyllaceae , Flores , Animales , Flores/fisiología , Fitomejoramiento , Polinización , Caryophyllaceae/genética , Fenotipo
2.
Psychiatry J ; 2013: 872146, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24236288

RESUMEN

In a series of community mental health promotion studies in Lofoten, Norway, the concept of sociocultural integration is used to describe properties of a local community that are related to people's psychological health. Starting with Durkheim's description of a cohesive society, we compare different concepts that are related to sociocultural integration, for example, sense of community, social capital, and social cohesion. We then examine the relationship of various individual oriented social psychological concepts to sociocultural integration. These concepts often share theoretical and operational definitions. The concept of sociocultural integration in the Lofoten studies was proved to be very valuable in understanding how the properties of a community can affect people's mental health and their social psychological properties. It has also shown its value in the planning of mental health services and demonstrating its success in concrete community-based mental health promotion projects. Thus they could make important contributions to further studies and actions in local communities where the intersection between the individual, their social network, and their local community occurs.

3.
Am J Bot ; 94(10): 1716-25, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21636368

RESUMEN

Sexual dimorphism may be especially pronounced in wind-pollinated species because they lack the constraints of biotically pollinated species that must present their pollen and stigmas in similar positions to ensure pollen transfer. Lacking these constraints, the sexes of wind-pollinated species may diverge in response to the different demands of pollen dispersal and receipt, depending on the magnitude of genetic correlations preventing divergence between sexes. Patterns of sexual dimorphism and genetic variation were investigated for inflorescence traits in Schiedea adamantis (Caryophyllaceae), a species well adapted to wind-pollination, and compared to S. salicaria, a species with fewer adaptations to wind pollination. For S. adamantis, dimorphism was pronounced for inflorescence condensation and its components, including lateral flower number and pedicel length. Within sexes, genetic correlations between traits may constrain the relative shape of the inflorescence. Correlations detected across sexes may retard the evolution of sexual dimorphism in inflorescence structure, including features favoring enhanced dispersal and receipt of pollen. Despite genetic correlations across sexes, common principal components analysis showed that genetic variance-covariance matrices (G matrices) differed significantly between the sexes, in part because of greater genetic variation for flower number in hermaphrodites than in females. G matrices also differed between closely related S. adamantis and S. salicaria, indicating the potential for divergent evolution of inflorescence structure despite general similarities in morphology and pollination biology.

4.
Med J Aust ; 180(7): 333-5, 2004 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-15059053

RESUMEN

Kidsnet was established in 1997 at the Children's Hospital at Westmead as a paediatric telephone triage service. The demand for Kidsnet increased from 18 327 in 1997/98 to 22 844 in 2001/02, with an average of 1669 callers per month. Most callers were able to proceed to seeking care at a more appropriate time and were satisfied with the service provided. The service is highly valued and the advice given perceived to be accurate. Kidsnet has shown that it can play a key role in providing safe advice to families.


Asunto(s)
Líneas Directas/estadística & datos numéricos , Enfermería Pediátrica/estadística & datos numéricos , Triaje/estadística & datos numéricos , Australia , Niño , Preescolar , Comportamiento del Consumidor/estadística & datos numéricos , Femenino , Investigación sobre Servicios de Salud/estadística & datos numéricos , Atención Domiciliaria de Salud/estadística & datos numéricos , Humanos , Lactante , Masculino , Evaluación de Necesidades/estadística & datos numéricos , Nueva Gales del Sur , Garantía de la Calidad de Atención de Salud/estadística & datos numéricos , Derivación y Consulta/estadística & datos numéricos , Revisión de Utilización de Recursos/estadística & datos numéricos
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