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2.
Proc Natl Acad Sci U S A ; 109(23): 8812-9, 2012 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-22615401

RESUMEN

Cultural ecosystem services (ES) are consistently recognized but not yet adequately defined or integrated within the ES framework. A substantial body of models, methods, and data relevant to cultural services has been developed within the social and behavioral sciences before and outside of the ES approach. A selective review of work in landscape aesthetics, cultural heritage, outdoor recreation, and spiritual significance demonstrates opportunities for operationally defining cultural services in terms of socioecological models, consistent with the larger set of ES. Such models explicitly link ecological structures and functions with cultural values and benefits, facilitating communication between scientists and stakeholders and enabling economic, multicriterion, deliberative evaluation and other methods that can clarify tradeoffs and synergies involving cultural ES. Based on this approach, a common representation is offered that frames cultural services, along with all ES, by the relative contribution of relevant ecological structures and functions and by applicable social evaluation approaches. This perspective provides a foundation for merging ecological and social science epistemologies to define and integrate cultural services better within the broader ES framework.


Asunto(s)
Cultura , Ecología/métodos , Ecosistema , Modelos Teóricos , Ciencias Sociales/métodos , Humanos , Comunicación Interdisciplinaria , Espiritualidad , Viaje
3.
PLoS One ; 5(7): e11877, 2010 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-20686709

RESUMEN

BACKGROUND: Knowledge of the relationship between accumulated thermal units and developmental stages of Chinook salmon embryos can be used to determine the approximate date of egg fertilization in natural redds, thus providing insight into oviposition timing of wild salmonids. However, few studies have documented time to different developmental stages of embryonic Chinook salmon and no reference color photographs are available. The objectives of this study were to construct an index relating developmental stages of hatchery-reared fall Chinook salmon embryos to time and temperature (e.g., degree days) and provide high-quality color photographs of each identified developmental stage. METHODOLOGY/PRINCIPAL FINDINGS: Fall Chinook salmon eggs were fertilized in a hatchery environment and sampled approximately every 72 h post-fertilization until 50% hatch. Known embryonic developmental features described for sockeye salmon were used to describe development of Chinook salmon embryos. A thermal sums model was used to describe the relationship between embryonic development rate and water temperature. Mean water temperature was 8.0 degrees C (range; 3.9-11.7 degrees C) during the study period. Nineteen stages of embryonic development were identified for fall Chinook salmon; two stages in the cleavage phase, one stage in the gastrulation phase, and sixteen stages in the organogenesis phase. The thermal sums model used in this study provided similar estimates of fall Chinook salmon embryonic development rate in water temperatures varying from 3.9-11.7 degrees C (mean=8 degrees C) to those from several other studies rearing embryos in constant 8 degrees C water temperature. CONCLUSIONS/SIGNIFICANCE: The developmental index provides a reasonable description of timing to known developmental stages of Chinook salmon embryos and was useful in determining developmental stages of wild fall Chinook salmon embryos excavated from redds in the Columbia River. This index should prove useful to other researchers who wish to approximate fertilization dates of Chinook salmon eggs from natural redds, assuming the thermal history of embryos is known.


Asunto(s)
Salmón/embriología , Temperatura , Animales , Embrión no Mamífero/citología , Embrión no Mamífero/fisiología , Fertilización/fisiología
4.
Steroids ; 73(2): 171-83, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18155739

RESUMEN

The syntheses and antimitotic activity of several novel analogs of 2-methoxyestradiol are described. Structural modifications include ring-D homologation, aromatization of the six-membered ring-D to a chrysine type molecule, and introduction of unsaturation in five-membered ring-D along with substitution of alkyl and ethynyl groups for the 17beta-hydroxy function. Of nine analogs synthesized, five have demonstrated superior antiproliferative activities compared to 2-methoxyestradiol.


Asunto(s)
Antimitóticos/síntesis química , Estradiol/análogos & derivados , 2-Metoxiestradiol , Antimitóticos/farmacología , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Endotelio Vascular/citología , Estradiol/síntesis química , Estradiol/farmacología , Humanos , Concentración 50 Inhibidora , Estructura Molecular , Relación Estructura-Actividad , Venas Umbilicales
5.
Steroids ; 73(2): 158-70, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18155740

RESUMEN

The syntheses and antimitotic activity of several novel 18a-homo-analogs of 2-methoxyestradiol are described. Structural modifications of the parent 2-methoxy-18a-homoestradiol include introduction of unsaturation in the D-ring and methylation of the 17-OH. Of seven analogs synthesized, one has demonstrated superior biological activities compared to 2-methoxyestradiol. The relationship between biological activity and the conformational preference of the 13-ethyl group as determined by computational analysis is discussed.


Asunto(s)
Antimitóticos/síntesis química , Estradiol/análogos & derivados , 2-Metoxiestradiol , Antimitóticos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Estradiol/síntesis química , Estradiol/farmacología , Humanos , Modelos Moleculares , Conformación Molecular , Relación Estructura-Actividad , Moduladores de Tubulina
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