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1.
J Exp Bot ; 65(1): 249-60, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24218327

RESUMEN

Crop improvement for yield and drought tolerance is challenging due to the complex genetic nature of these traits and environmental dependencies. This study reports that transgenic over-expression of Zea mays AR GOS1 (ZAR1) enhanced maize organ growth, grain yield, and drought-stress tolerance. The ZAR1 transgene exhibited environmental interactions, with yield increase under Temperate Dry and yield reduction under Temperate Humid or High Latitude environments. Native ZAR1 allele variation associated with drought-stress tolerance. Two founder alleles identified in the mid-maturity germplasm of North America now predominate in Pioneer's modern breeding programme, and have distinct proteins, promoters and expression patterns. These two major alleles show heterotic group partitioning, with one predominant in Pioneer's female and the other in the male heterotic groups, respectively. These two alleles also associate with favourable crop performance when heterozygous. Allele-specific transgene testing showed that, of the two alleles discussed here, each allele differed in their impact on yield and environmental interactions. Moreover, when transgenically stacked together the allelic pair showed yield and environmental performance advantages over either single allele, resembling heterosis effects. This work demonstrates differences in transgenic efficacy of native alleles and the differences reflect their association with hybrid breeding performance.


Asunto(s)
Vigor Híbrido , Proteínas de Plantas/genética , Zea mays/genética , Alelos , Secuencia de Bases , Biomasa , Cruzamiento , Sequías , Expresión Génica , Interacción Gen-Ambiente , Variación Genética , Haplotipos , Datos de Secuencia Molecular , Familia de Multigenes , Fenotipo , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Semillas/genética , Semillas/crecimiento & desarrollo , Semillas/fisiología , Análisis de Secuencia de ADN , Transgenes , Zea mays/crecimiento & desarrollo , Zea mays/fisiología
2.
J Health Psychol ; 15(7): 982-92, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20616182

RESUMEN

Community health psychology provides a framework for local citizens themselves to systematically affect change in health and social inequalities, particularly through Participatory Action Research (PAR). The Cambodian NGO SiRCHESI launched a 24-month Hotel Apprenticeship Program (HAP) in 2006 to provide literacy, English, social skills, health education, hotel skills-training, work experience and a living wage to women formerly selling beer in restaurants; there they had faced workplace risks including HIV/AIDS, alcohol overuse, violence and sexual coercion. Quantitative and qualitative analyses indicate changes in health-related knowledge, behaviour, self-image and empowerment, as HAP trainees were monitored and evaluated within their new career trajectories.


Asunto(s)
Movilidad Laboral , Escolaridad , Pobreza/prevención & control , Poder Psicológico , Conducta de Reducción del Riesgo , Cambodia , Femenino , Humanos , Evaluación de Programas y Proyectos de Salud
3.
Perception ; 34(3): 319-40, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15895630

RESUMEN

Averaged face composites, which represent the central tendency of a familiar population of faces, are attractive. If this prototypicality contributes to their appeal, then averaged composites should be more attractive when their component faces come from a familiar, own-race population than when they come from a less familiar, other-race population. We compared the attractiveness of own-race composites, other-race composites, and mixed-race composites (where the component faces were from both races). In experiment 1, Caucasian participants rated own-race composites as more attractive than other-race composites, but only for male faces. However, mixed-race (Caucasian/Japanese) composites were significantly more attractive than own-race composites, particularly for the opposite sex. In experiment 2, Caucasian and Japanese participants living in Australia and Japan, respectively, selected the most attractive face from a continuum with exaggerated Caucasian characteristics at one end and exaggerated Japanese characteristics at the other, with intervening images including a Caucasian averaged composite, a mixed-race averaged composite, and a Japanese averaged composite. The most attractive face was, again, a mixed-race composite, for both Caucasian and Japanese participants. In experiment 3, Caucasian participants rated individual Eurasian faces as significantly more attractive than either Caucasian or Asian faces. Similar results were obtained with composites. Eurasian faces and composites were also rated as healthier than Caucasian or Asian faces and composites, respectively. These results suggest that signs of health may be more important than prototypicality in making average faces attractive.


Asunto(s)
Señales (Psicología) , Estética , Etnicidad , Fisiognomía , Pueblo Asiatico , Femenino , Humanos , Juicio , Masculino , Psicofísica , Grupos Raciales , Población Blanca
4.
Curr Biol ; 14(23): 2119-23, 2004 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-15589154

RESUMEN

Humans have an impressive ability to discriminate between faces despite their similarity as visual patterns. This expertise relies on configural coding of spatial relations between face features and/or holistic coding of overall facial structure. These expert face-coding mechanisms appear to be engaged most effectively by upright faces, with inverted faces engaging primarily feature-coding mechanisms. We show that opposite figural aftereffects can be induced simultaneously for upright and inverted faces, demonstrating that distinct neural populations code upright and inverted faces. This result also suggests that expert (upright) face-coding mechanisms can be selectively adapted. These aftereffects occur for judgments of face normality and face gender and are robust to changes in face size, ruling out adaptation of low-level, retinotopically organized coding mechanisms. Our results suggest a resolution of a paradox in the face recognition literature. Neuroimaging studies have found surprisingly little orientation selectivity in the fusiform face area (FFA) despite evidence that this region plays a role in expert face coding and that expert face-coding mechanisms are selectively engaged by upright faces. Our results, demonstrating orientation-contingent adaptation of face-coding mechanisms, suggest that the FFA's apparent lack of orientation selectivity may be an artifact of averaging across distinct populations within the FFA that respond to upright and inverted faces.


Asunto(s)
Cara , Efecto Tardío Figurativo/fisiología , Reconocimiento Visual de Modelos/fisiología , Distorsión de la Percepción/fisiología , Adulto , Análisis de Varianza , Femenino , Humanos , Masculino , Orientación , Estimulación Luminosa , Factores Sexuales
5.
Genetics ; 166(4): 1715-25, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15126392

RESUMEN

Classical quantitative genetics has applied linear modeling to the problem of mapping genotypic to phenotypic variation. Much of this theory was developed prior to the availability of molecular biology. The current understanding of the mechanisms of gene expression indicates the importance of nonlinear effects resulting from gene interactions. We provide a bridge between genetics and gene network theories by relating key concepts from quantitative genetics to the parameters, variables, and performance functions of genetic networks. We illustrate this methodology by simulating the genetic switch controlling galactose metabolism in yeast and its response to selection for a population of individuals. Results indicate that genes have heterogeneous contributions to phenotypes and that additive and nonadditive effects are context dependent. Early cycles of selection suggest strong additive effects attributed to some genes. Later cycles suggest the presence of strong context-dependent nonadditive effects that are conditional on the outcomes of earlier selection cycles. A single favorable allele cannot be consistently identified for most loci. These results highlight the complications that can arise with the presence of nonlinear effects associated with genes acting in networks when selection is conducted on a population of individuals segregating for the genes contributing to the network.


Asunto(s)
Galactosa/genética , Expresión Génica , Genética de Población , Modelos Moleculares , Fenotipo , Selección Genética , Alelos , Simulación por Computador , Galactosa/metabolismo , Genotipo , Dinámicas no Lineales , Levaduras
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