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991.
di Girolamo FA Sabatini DJ Fasan RA Echegoyen M Vela M Pereira CA Maure P 《Veterinary immunology and immunopathology》2012,145(1-2):563-566
In this work two cytokines were used in combination with inactivated bacteria (bacterin) to test the bovine conjuctival immune response to the pathogen Moraxella bovis, the causative agent of Infectious bovine keratoconjunctivitis (IBK). Treatments using the bacterin vaccine combined with interleukin-2 and interferon-α as adjuvants (Group A), the bacterin vaccine only (Group B), and controls without treatment (Group C), were applied by ocular spraying to evaluate the local immune response in the corneal structure of cattle experimentally infected with M. bovis. Six weeks after infection, 14 out of a total of 34 animals presented different corneal lesions; 9 corresponding to the control group C, 4 to the group B and only one to the group A. According to the clinical manifestations, a numeric score was calculated. Control animals presented the highest score value (12 points), followed by group B (7.5 points) and group A (1 point). These results suggest that the addition of cytokines to M. bovis treatments can reduce not only eye injuries caused by IBK but also the number of diseased animals. 相似文献
992.
Rosilei A. Garcia Alexandre Monteiro de Carvalho Jo?o Vicente de Figueiredo Latorraca Jorge Luis Monteiro de Matos Wanessa A. Santos Rafael Fonseca de Medeiros Silva 《Wood Science and Technology》2012,46(1-3):41-52
The objectives of this study were to evaluate the effect of heat treatment of eucalypt wood (Eucalyptus grandis Hill ex Maiden) on the dynamic modulus of elasticity by using the stress wave nondestructive method and also to determine the air-dry density variation, weight loss and equilibrium moisture content following treatment. Heat treatments were performed at four different temperatures (180, 200, 215 and 230°C) and for three different durations (15?min, 2 and 4?h). The results revealed a significant reduction in air-dry density following heat treatment independent of temperature and time. A significant weight loss was observed between and within treatments. The treatment at 230°C for 2 and 4?h produced a weight loss of 20.5 and 26.5%, respectively, which was statistically different from other treatment conditions. The dynamic modulus of elasticity decreased by about 13% in the most severe treatment (230°C for 4?h). Depending on the temperature and time, the equilibrium moisture content was significantly reduced within the range of 40–74%. 相似文献
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995.
Diogo Alagador Maria Trivi?o Jorge Orestes Cerdeira Raul Brás Mar Cabeza Miguel Bastos Araújo 《Landscape Ecology》2012,27(2):291-301
Habitat fragmentation is one of the greatest threats to biodiversity. To minimise the effect of fragmentation on biodiversity,
connectivity between otherwise isolated habitats should be promoted. However, the identification of linkages favouring connectivity
is not trivial. Firstly, they compete with other land uses, so they need to be cost-efficient. Secondly, linkages for one
species might be barriers for others, so they should effectively account for distinct mobility requirements. Thirdly, detailed
information on the auto-ecology of most of the species is lacking, so linkages need being defined based on surrogates. In
order to address these challenges we develop a framework that (a) identifies environmentally-similar habitats; (b) identifies
environmental barriers (i.e., regions with a very distinct environment from the areas to be linked), and; (c) determines cost-efficient
linkages between environmentally-similar habitats, free from environmental barriers. The assumption is that species with similar
ecological requirements occupy the same environments, so environmental similarity provides a rationale for the identification
of the areas that need to be linked. A variant of the classical minimum Steiner tree problem in graphs is used to address
c). We present a heuristic for this problem that is capable of handling large datasets. To illustrate the framework we identify
linkages between environmentally-similar protected areas in the Iberian Peninsula. The Natura 2000 network is used as a positive
‘attractor’ of links while the human footprint is used as ‘repellent’ of links. We compare the outcomes of our approach with
cost-efficient networks linking protected areas that disregard the effect of environmental barriers. As expected, the latter
achieved a smaller area covered with linkages, but with barriers that can significantly reduce the permeability of the landscape
for the dispersal of some species. 相似文献
996.
Angaman DM Petrizzo R Hernández-Gras F Romero-Segura C Pateraki I Busquets M Boronat A 《Plant methods》2012,8(1):1
Background
Carotenoids are the most widespread group of pigments found in nature. In addition to their role in the physiology of the plant, carotenoids also have nutritional relevance as their incorporation in the human diet provides health benefits. In non-photosynthetic tissues, carotenoids are synthesized and stored in specialized plastids called chromoplasts. At present very little is known about the origin of the metabolic precursors and cofactors required to sustain the high rate of carotenoid biosynthesis in these plastids. Recent proteomic data have revealed a number of biochemical and metabolic processes potentially operating in fruit chromoplasts. However, considering that chloroplast to chromoplast differentiation is a very rapid process during fruit ripening, there is the possibility that some of the proteins identified in the proteomic analysis could represent remnants no longer having a functional role in chromoplasts. Therefore, experimental validation is necessary to prove whether these predicted processes are actually operative in chromoplasts. 相似文献997.
Aurelio Hernández-Bautista Ricardo Lobato-Ortiz J. Jesús García-Zavala Mario Rocandio-Rodríguez José Apolinar Mejía-Contreras José Luis Chávez-Servia José Armando García-Velazquez 《Euphytica》2018,214(2):37
Previous findings in some crops suggest that parental distance is correlated with heterosis and agronomic performance. However, this pattern is not always evident in the progeny. The present study aimed to assess the relationship of parental distance with the agronomic performance of raspberry families and three estimators based on non-environmental effects: specific combining ability, general combining ability, and best linear unbiased prediction. A total of 35 genotypes, including eight open-pollinated raspberry cultivars and their 28 F1 hybrids, were scored for vegetative and fruit traits. The relationship between estimators and parental distance ranged from 0.02 to 0.66. The estimators based on purely additive effects were superior to the per se performance of raspberry crosses. Additionally, it was observed that the specific combining ability—as an estimator associated with the parental genetic relatedness—performed poorly, and low correlation coefficients were observed for most of the traits. It was found that the degree of association for the estimators increased when narrow-sense heritability was high. It is concluded that the estimators based on only additive effects show a better association with parental relatedness, and therefore parental distance was an effective parameter in identifying crosses with high yield and large fruit size. 相似文献
998.
Juan Paulo Xavier de Freitas Rafael Parreira Diniz Vanderlei da Silva Santos Eder Jorge de Oliveira 《Euphytica》2018,214(7):127
The objective of this study was to estimate and compare genetic parameters in early cassava breeding phases (clonal evaluation trials—CET and preliminary yield trials—PYT) in full-sib (F1) and self-pollinated (S1) families, besides estimating the genetic gains. Twenty-three F1 and six S1 families were evaluated using the augmented block design in CET and the randomized complete block design in PYT for fresh root yield (FRY), root dry matter content (DMC) and starch yield (STY). In CET, most of the variance was due to environmental (\(\sigma_{e}^{2}\)) followed by variance within F1 and S1 (\(\sigma_{Clone/Fam}^{2}\)) families, with the exception of DMC in S1 families. PYT presented the opposite behavior. In contrast, specifically for S1 families, the variance between families (\(\sigma_{ Fam}^{2}\)) was more important than \(\sigma_{e}^{2}\) and \(\sigma_{Clone/Fam}^{2}\) in PYT. The heritability of families (\(h_{Fam}^{2}\)) was lower than individual broad-sense heritability (\(h_{g}^{2}\)) in all trials and families. Regardless of the family type and trial, family accuracy (\(r_{ggFam}\)) was lower than the clone accuracies (\(r_{ggCl}\)). Predicted gains using the selection index (SI) applied to best linear unbiased prediction (BLUP) were higher in PYT compared with CET and higher in F1 families in comparison with S1. There was also low coincidence in clone selection in both trials (30 and 45% for F1 and S1 families, respectively). For cassava breeding, it is recommended to obtain a higher number of clones per family and to use the SI with moderate intensity, particularly in CET. 相似文献
999.
Paulo Henrique Gomes Alves de Oliveira Ana Claudia Oliveira Barbosa Rafael Parreira Diniz Claudia Fortes Ferreira Eder Jorge de Oliveira 《Euphytica》2018,214(6):92
The need to develop new cassava (Manihot esculenta Crantz) varieties with different starch characteristics has greatly motivated new research. The aim of this study was to evaluate morphological alterations in starch granules as well as genetic gains in segregating S1 cassava populations. Starch from accessions (S0): BGM0222, BGM1378 and BGM1662 and from their self-fertilized progenies (S1): F0222, F1378 and F1662, with 78, 80 and 76 individuals, respectively, were evaluated for the following traits: area (ArStGr, µm2), perimeter (PrStGr, µm), length (LeStGr, µm) and number of starch granules (NuStGr). Moreover, some agronomic traits of the S1 progenies were evaluated at harvest such as: plant height (PlaHei), shoot yield (ShoYi), root yield (RoYi), starch yield (StYi), and root dry matter content (DMC). With the selection of transgressive individuals in S1 progenies, it is possible to obtain selection gains for values higher and lower than the average of the S0 genitors, whereas selection gains can reach up to 16.58, 8.39, 7.87 and 34.18% for ArStGr, LeStGr, PrStGr, and NuStGr, respectively. Average size of the starch granule varied from 9.8 to 12.37 µm among individuals in an S1 progeny. Positive and high correlations between the individuals were found for some morphological characteristics of the cassava starch granule but not strongly correlated with agronomic traits. Therefore, it is possible to select S1 cassava individuals for agronomic characteristics without losing other important starch traits. Cassava-segregating populations allow the obtainment of individuals with different morphological characteristics as for starch granules, enabling obtainment of genetic gains with the selection. 相似文献
1000.
Carmen Pérez-Sirvent Carmen Hernández-Pérez María José Martínez-Sánchez Mari Luz García-Lorenzo Jaume Bech 《Journal of Soils and Sediments》2017,17(5):1384-1393