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131.
132.
Inmaculada Farran Alicia Fernandez-San Millan Maria Ancin Luis Larraya Jon Veramendi 《Molecular breeding : new strategies in plant improvement》2014,34(2):457-469
Bioethanol is mainly produced from food crops such as sugar cane and maize, and this has been held partly responsible for the rise of food commodity prices. Tobacco, integrated in biorefinery facilities for the extraction of different compounds, could become an alternative feedstock for biofuel production. When grown for energy production, using high plant densities and several mowings during the growing season, tobacco can produce large amounts of inexpensive green biomass. We have bred two commercial tobacco cultivars (Virginia Gold and Havana 503B) to increase the carbohydrate content by the overexpression of thioredoxin f in the chloroplast. Marker-free transplastomic plants were recovered and their agronomic performance under field conditions was evaluated. These plants were phenotypically equivalent to their wild types yet showed increased starch (up to 280 %) and soluble sugar (up to 74 %) contents in leaves relative to their control plants. Fermentable sugars released from the stalk were also higher (up to 24 %) for transplastomic plants. After heat pretreatment, enzymatic hydrolysis and yeast fermentation of leaf and stalk hydrolysates, an average of 20–40 % more ethanol was obtained from transplastomic plants than their wild-type controls. We propose an integral exploitation of the entire tobacco plant managed as a forage crop (harvesting sugar and starch-rich leaves and lignocellulosic stalks) that could considerably cheapen the entire production process. 相似文献
133.
134.
M. Carmen Martínez-Ballesta Luis López-Pérez Mercedes Hernández Carmen López-Berenguer Nieves Fernández-García Micaela Carvajal 《Phytochemistry Reviews》2008,7(2):251-260
Phytochemicals in vegetables are known to be responsible for protective effects against many human diseases, including cardiovascular
diseases and different types of cancer. Environmental conditions and physiological factors may modify the amounts of these
compounds present in vegetables and fruits, but also crop management strategies could increase the production of phytochemicals.
Therefore, the effects of mineral nutrition, soil composition and water content on the production of phytochemicals have been
considered in the development of different fertilisation strategies, efficient water management and techniques such as grafting.
Finally, the contents of health-promoting compounds in vegetables and fruits depend both quantitatively and qualitatively
on their genetic bases. Thus, conventional breeding and genetic modification have been developed as new methodologies to enhance
the nutritional properties of plants.
M. C. Martínez-Ballesta, L. López-Pérez, M. Hernández, C. López-Berenguer, N. Fernández-García contributed equally. 相似文献
135.
136.
Catherine Fabre Assou El Battari Catherine Bellan Eric Pasqualini Jacques Marvaldi Dominique Lombardo Jos Luis 《Peptides》1993,14(6):1331-1338
The human pancreatic cell line BxPC-3 displays two classes of binding sites with high and low affinity for VIP. The order of potency of VIP-related peptides in inhibiting either [125I]VIP or [125I]N-AcPACAP27 binding and in stimulating cAMP production was typical of the human VIP receptor. By combining affinity labeling with glycosidase treatments, we have characterized the VIP receptor as a Mr = 68,200 glycoprotein, consisting of a Mr = 39,300 polypeptide core with at least three N-linked oligosaccharide chains. In addition, our results revealed the presence of a low amount of sialic acid residues in the carbohydrate moiety of receptor. 相似文献
137.
Julien Foucaud Céline Moreno Marta Pascual Enrico L. Rezende Luis E. Castañeda Patricia Gibert Frederic Mery 《Ecology and evolution》2016,6(6):1725-1736
The success of invasive species is tightly linked to their fitness in a putatively novel environment. While quantitative components of fitness have been studied extensively in the context of invasive species, fewer studies have looked at qualitative components of fitness, such as behavioral plasticity, and their interaction with quantitative components, despite intuitive benefits over the course of an invasion. In particular, learning is a form of behavioral plasticity that makes it possible to finely tune behavior according to environmental conditions. Learning can be crucial for survival and reproduction of introduced organisms in novel areas, for example, for detecting new predators, or finding mates or oviposition sites. Here we explored how oviposition performance evolved in relation to both fecundity and learning during an invasion, using native and introduced Drosophila subobscura populations performing an ecologically relevant task. Our results indicated that, under comparable conditions, invasive populations performed better during our oviposition task than did native populations. This was because invasive populations had higher fecundity, together with similar cognitive performance when compared to native populations, and that there was no interaction between learning and fecundity. Unexpectedly, our study did not reveal an allocation trade‐off (i.e., a negative relationship) between learning and fecundity. On the contrary, the pattern we observed was more consistent with an acquisition trade‐off, meaning that fecundity could be limited by availability of resources, unlike cognitive ability. This pattern might be the consequence of escaping natural enemies and/or competitors during the introduction. The apparent lack of evolution of learning may indicate that the introduced population did not face novel cognitive challenges in the new environment (i.e., cognitive “pre‐adaptation”). Alternatively, the evolution of learning may have been transient and therefore not detected. 相似文献
138.
In this paper, we further investigate the new paradigm for the rupture of thin cap fibroatheroma (TCFA) proposed in Vengrenyuk et al. (2006 PNAS 103:14678) using a multilevel micro-CT based 3D numerical modeling. The new paradigm proposes that the rupture of TCFA is due to stress-induced interfacial debonding of cellular--level, 10-20 microm microcalcifications in the fibrous cap proper. Such microcalcifications, which lie below the visibility of current in vivo imaging techniques, were detected for the first time using confocal microscopy and high resolution microcomputed tomography (micro-CT) imaging in Vengrenyuk et al. (2006) In the present study, we use high resolution (7 microm) micro-CT imaging to construct accurate geometries of both these microcalcifications and larger mm size macrocalcifications at the cap shoulders to evaluate their biomechanical stability. The analysis shows that cellular-level calcifications by themselves are not dangerous unless they lie in a region of high background stress. This high level of background stress only occurs in caps whose thickness is < approximately 80 microm. Whereas a spherical microcalcification will increase peak circumferential stress (PCS) by a factor of two, in agreement with previous local analytical solutions, this can be increased several fold by elongated microcalcifications. The most dangerous situation is when a microinclusion appears in close proximity to a region where the PCS is already high. This stress will be substantially increased if the inclusion is elongated. In contrast, macrocalcifications at the cap shoulders are shown to actually increase plaque stability. 相似文献
139.
Luis Giménez-Benavides Raúl García-Camacho José María Iriondo Adrián Escudero 《Evolutionary ecology》2011,25(4):777-794
Under climate warming, plants will undergo novel selective pressures to adjust reproductive timing. Adjustment between reproductive
phenology and environment is expected to be higher in arctic and alpine habitats because the growing season is considerably
short. As early- and late-flowering species reproduce under very different environmental conditions, selective pressures on
flowering phenology and potential effects of climate change are likely to differ between them. However, there is no agreement
on the magnitude of the benefits and costs of early- vs. late-flowering species under a global warming scenario. In spite
of its relevance, phenotypic selection on flowering phenology has rarely been explored in alpine plants and never in Mediterranean
high mountain species, where selective pressures are very different due to the summer drought imposed over the short growth
season. We hypothesized that late-flowering plants in Mediterranean mountains should present stronger selective pressures
towards early onset of reproduction than early-flowering species, because less water is available in the soil as growing season
progresses. We performed selection analyses on flowering onset and duration in two high mountain species of contrasting phenology.
Since phenotypic selection can be highly context-dependent, we studied several populations of each species for 2 years, covering
their local altitudinal ranges and their different microhabitats. Surrogates of biotic selective agents, like fruitset for
pollinators and flower and fruit loss for flower and seed predators, were included in the analysis. Differences between the
early- and the late-flowering species were less than expected. A consistent negative correlational selection of flowering
onset and duration was found affecting plant fitness, i.e., plants that bloomed earlier flowered for longer periods improving
plant fitness. Nevertheless, the late-flowering species may experience higher risks under climate warming because in extremely
warm and dry years the earlier season does not bring about a longer flowering duration due to summer drought. 相似文献
140.
Julio Álvarez Andrés Perez Sergio Marqués Javier Bezos Anna Grau Maria Luisa de la Cruz Beatriz Romero Jose Luis Saez Maria del Rosario Esquivel Maria del Carmen Martínez Olga Mínguez Lucía de Juan Lucas Domínguez 《BMC veterinary research》2014,10(1):1-10