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1.
Physiol Plant ; 175(6): e14080, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38148199

RESUMEN

The development of light emitting diodes (LED) gives new possibilities to use the light spectrum to manipulate plant morphology and physiology in plant production and research. Here, vegetative Chrysanthemum × morifolium were grown at a photosynthetic photon flux density of 230 µmol m-2 s-1 under monochromatic blue, cyan, green, and red, and polychromatic red:blue or white light with the objective to investigate the effect on plant morphology, gas exchange and metabolic profile. After 33 days of growth, branching and leaf number increased from blue to red light, while area per leaf, leaf weight fraction, flavonol index, and stomatal density and conductance decreased, while dry matter production was mostly unaffected. Plants grown under red light had decreased photosynthesis performance compared with blue or white light-grown plants. The primary and secondary metabolites, such as organic acids, amino acids and phenylpropanoids (measured by non-targeted metabolomics of polar metabolites), were regulated differently under the different light qualities. Specifically, the levels of reduced ascorbic acid and its oxidation products, and the total ascorbate pool, were significantly different between blue light-grown plants and plants grown under white or red:blue light, which imply photosynthesis-driven alterations in oxidative pressure under different light regimens. The overall differences in plant phenotype, inflicted by blue, red:blue or red light, are probably due to a shift in balance between regulatory pathways controlled by blue light receptors and/or phytochrome. Although morphology, physiology, and metabolism differed substantially between plants grown under different qualities of light, these changes had limited effects on biomass accumulation.


Asunto(s)
Chrysanthemum , Biomasa , Fotosíntesis/fisiología , Hojas de la Planta/metabolismo , Plantas
2.
Plants (Basel) ; 12(3)2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36771521

RESUMEN

Three genotypes of wheat grown at two CO2 concentrations were used in a drought experiment, where water was withheld from the pots at anthesis until stomatal conductance (gs) dropped below 10% of the control and photosynthesis (A) approached zero. The genotypes had different leaf area (Gladius < LM19 < LM62) and while photosynthesis and shoot growth were boosted by elevated CO2, the water use and drying rate were more determined by canopy size than by stomatal density and conductance. The genotypes responded differently regarding number of fertile tillers, seeds per spike and 1000 kernel weight and, surprisingly, the largest genotype (LM62) with high water use showed the lowest relative decrease in grain yield. The maximum photochemical efficiency of photosystem II (Fv/Fm) was only affected on the last day of the drought when the stomata were almost closed although some variation in A was still seen between the genotypes. A close correlation was found between Fv/Fm and % loss of grain yield. It indicates that the precise final physiological stress level measured by Fv/Fm at anthesis/early kernel filling could effectively predict percentage final yield loss, and LM62 was slightly less stressed than the other genotypes, due to only a small discrepancy in finalising the drying period. Therefore, Fv/Fm can be used as a proxy for estimating the yield performance of wheat after severe drought at anthesis.

3.
Scand J Psychol ; 50(1): 47-54, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18980602

RESUMEN

This study examines reliability and validity and establish Danish norms for the Danish version of the Beck Youth Inventories (BYI) (Beck, Beck & Jolly, 2001), which consists of five self-report scales; Self-Concept (BSCI), Anxiety (BAI), Depression (BDI), Anger (BANI) and Disruptive Behavior (BDBI). A total of 1,116 school children and 128 clinical children, aged 7-14, completed BYI. Internal consistency coefficients were high. Most test-retest correlations were >0.70. A test-retest difference was found for BAI. Exploratory and confirmatory factor analysis indicated that the five factor structure of the instrument was justified. The BSCI, BAI and BDI discriminated moderately between the norming sample and the clinical group, and the latter group included more children who exceeded the 90th percentile of the norming sample. Diagnostic groups scored higher on relevant scales than norms. Only BSCI and BDI differentiated between diagnostic groups. The BYI showed acceptable internal consistency and test-retest stability, except for BAI. The BYI did not adequately differentiate between internalizing disorders.


Asunto(s)
Trastornos Mentales/diagnóstico , Pruebas Psicológicas , Adolescente , Estudios de Casos y Controles , Niño , Dinamarca , Análisis Factorial , Femenino , Humanos , Masculino , Valores de Referencia , Reproducibilidad de los Resultados
4.
Eur Child Adolesc Psychiatry ; 13 Suppl 3: 39-63, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15692879

RESUMEN

The Five to Fifteen parent questionnaire (FTF) was developed to offer a neuropsychological dimension to the assessment of children with Attention Deficit/Hyperactivity Disorder and other child psychiatric disorders. The domains included in the FTF were motor skills, executive functions, perception, memory, language, social skills and learning, in addition to a domain for emotional and behavioural problems. The aim of the present study was to test the clinical validity and utility of the FTF with a main focus on discriminant and criterion validity. The clinical sample consisted of 155 clinically diagnosed children (ICD-10 criteria), 102 were tested with WISC-III. The parents rated their children independent of the diagnostic evaluation. The results were presented as profiles. These clinical profiles were compared to those of a Swedish norm sample consisting of 854 children from the age of five to fifteen. Results demonstrated that the profiles for the clinical groups were similar in forms and levels to those of the upper 10 percent of the norm sample (those with most difficulties). Five out of eight FTF domains discriminated significantly between diagnostic groups in the clinical sample. Influence of IQ, gender and age on the results were low. Three out of four relevant FTF domains correlated significantly with corresponding WISC-III indexes/measures. The clinical utility of individual children's profiles were demonstrated. On the whole, the findings supported the clinical validity and utility of the FTF.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/diagnóstico , Trastornos de la Conducta Infantil/diagnóstico , Escalas de Valoración Psiquiátrica , Encuestas y Cuestionarios , Niño , Comorbilidad , Femenino , Humanos , Discapacidades para el Aprendizaje/diagnóstico , Masculino , Relaciones Padres-Hijo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
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