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排序方式: 共有880条查询结果,搜索用时 15 毫秒
851.
852.
Rita Bastos Mário Santos Jaime Albino Ramos Joana Vicente Carlos Guerra Joaquim Alonso João Honrado Ricardo Santos Ceia Sérgio Timóteo João Alexandre Cabral 《Biological conservation》2012,147(1):243-254
The Azores bullfinch (Pyrrhula murina) is an endemic bird of São Miguel island (Azores Archipelago, Portugal), currently threatened by two of the major causes of biodiversity loss worldwide: invasion of native habitats by exotic plants and habitat destruction by land use changes. The aim of this research was to develop and test a novel spatially explicit modelling framework that predicts the Azores bullfinch responses to alternative realistic scenarios of native forest management. This was done by integrating Multi-Model Inference statistical analysis, Stochastic-Dynamic Modelling and Geographic Information Systems under a common framework relating bird population trends to changes in the surrounding habitats. Overall, in the next 25 years, the Azores bullfinch breeding population was predicted to increase around 19% as a consequence of habitat management actions already implemented (“LIFE Priolo” project) or around 27% in the context of realistic future habitat restoration scenarios. These results represent, respectively, a supplementary increase of more 6% or more 13% in the Azores bullfinch abundance when compared with the trends simulated for the scenario without management. Nevertheless, those actions seemed to be relatively ineffective in promoting the expansion of the species from the actual restricted favourable area, essentially due to local forestry dynamics and on-going plant invasion processes. This novel integrative approach provides a promising baseline to support ecological models with increased realism and predictive power, making the outputs more useful and intuitive to decision-makers and environmental managers. 相似文献
853.
854.
Agostina Collavino Andrea A. Zanini Ricardo Medina Silvia Schaller Liliana Di Feo 《Plant pathology》2022,71(4):980-989
Cassava is an important crop with great economic and social significance in many countries. Most of its biomass is usable: storage roots can be destined for industry or fresh consumption, leaves are a source of protein, vitamins, and minerals, and stems can be used as propagation material. Due to its vegetative propagation, cassava yield is greatly constrained by viral diseases. Cassava common mosaic virus (CsCMV), one of the most widely spread viruses in Latin America, is the only cassava-infecting potexvirus able to cause disease in a single infection: cassava common mosaic disease (CCMD). Here, we evaluated the effect of an Argentinian strain of CsCMV on several agronomic traits. Field trials were established in north-eastern Argentina for three successive cropping seasons, 2016/17, 2017/18, and 2018/19. CsCMV presence was confirmed by PCR or ELISA tests in mechanically inoculated cassava plants. The evaluated traits were plant height (PH), total fresh weight (TFW), shoot fresh weight (SFW), diameter and FW of tuberous root per plant (TRD and FWTR), FW of each individual tuberous root (FWiTR), length and number of tuberous roots (TRL and TRN), harvest index (HI), and estimated yield of tuberous root (EY) in both infected and noninfected plants. Significant yield losses were recorded in infected plants. The most affected traits were EY and FWTR (both showing 44.3% of losses), followed by TFW, SFW, TRN, and FWiTR (37.8%, 33.5%, 29.9%, and 24.8% of losses, respectively). These losses are extremely high for Argentina, where this crop provides food security and demand for the raw material is unsatisfied. 相似文献
855.
Nugroho Cipto Cumagun Christian Joseph R. Oliva Ricardo 《European journal of plant pathology / European Foundation for Plant Pathology》2022,163(4):951-960
European Journal of Plant Pathology - Rice bacterial blight is caused by Xanthomonas oryzae pv. oryzae (Xoo), which is one of the most common diseases in most rice-growing countries. The study aims... 相似文献
856.
Ruiz R Kang H Detcheverry FA Dobisz E Kercher DS Albrecht TR de Pablo JJ Nealey PF 《Science (New York, N.Y.)》2008,321(5891):936-939
Self-assembling materials spontaneously form structures at length scales of interest in nanotechnology. In the particular case of block copolymers, the thermodynamic driving forces for self-assembly are small, and low-energy defects can get easily trapped. We directed the assembly of defect-free arrays of isolated block copolymer domains at densities up to 1 terabit per square inch on chemically patterned surfaces. In comparing the assembled structures to the chemical pattern, the density is increased by a factor of four, the size is reduced by a factor of two, and the dimensional uniformity is vastly improved. 相似文献
857.
Martinez RN Sereno PC Alcober OA Colombi CE Renne PR Montañez IP Currie BS 《Science (New York, N.Y.)》2011,331(6014):206-210
Upper Triassic rocks in northwestern Argentina preserve the most complete record of dinosaurs before their rise to dominance in the Early Jurassic. Here, we describe a previously unidentified basal theropod, reassess its contemporary Eoraptor as a basal sauropodomorph, divide the faunal record of the Ischigualasto Formation with biozones, and bracket the formation with (40)Ar/(39)Ar ages. Some 230 million years ago in the Late Triassic (mid Carnian), the earliest dinosaurs were the dominant terrestrial carnivores and small herbivores in southwestern Pangaea. The extinction of nondinosaurian herbivores is sequential and is not linked to an increase in dinosaurian diversity, which weakens the predominant scenario for dinosaurian ascendancy as opportunistic replacement. 相似文献
858.
859.
Ricardo Bressani Eloisa Hernandez J. Edgar Braham 《Plant foods for human nutrition (Dordrecht, Netherlands)》1988,38(1):5-21
The purpose of this study was to determine the effect of bean polyphenolics on bean protein digestibility in humans. Steam pressure cooking decreased tannic acid in beans by: 38.2 (white), 23.9 (red), 38.5 (white:black mixture, 50:50), 20.5 (Ipala black) and 44.4% (Jalpatagua black). The reduction in catechin was: 57.5, 97.6, 83.0, 78.7 and 88.4%, respectively. The content of tannic acid in dried cooked beans was: 284.9 in white, 834.5 in red, 620.2 in the white:black mixture, 1,021 in Ipala black and 1,009 mg/100 g in the Jalpatagua black bean. These percentages correlate significantly with fecal nitrogen (r=0.29, p<0.05). Catechin of the dried cooked beans was 7.5 in white, 27.4 in red, 25.4 in the white:black mixture (50:50), and 60.1 and 55.5 mg/100 g in each of the black cultivars, and correlated significantly with fecal nitrogen (r=0.34, p<0.01), absorbed nitrogen (r=–0.37, p<0.01) and protein digestibility (r=–0.35, p<0.01). It was concluded that one of the factors that reduces bean protein digestibility is the polyphenlic compound. 相似文献
860.
Arlene Wolzak Dr. Ricardo Bressani Roberto Gomez Brenes 《Plant foods for human nutrition (Dordrecht, Netherlands)》1981,31(1):31-43
Research was performed to determine the suitability of the rapid multienzymatic assay for in vitro protein digestibility estimation by using a group of native and thermally processed vegetable proteins which constitute the staple foods in developing countries. The in vitro digestibility was assessed by measuring the extent to which the pH of the protein suspension dropped when treated with a multienzyme system consisting of trypsin, chymotrypsin, and peptidase for 10 min, andStreptomyces griseus protease for 10 min more. The best correlation occurred between in vivo rat protein digestibility and the pH of the protein suspension after 15 min enzymatic treatment. The response of different types of proteins to the multienzyme assay was different, and thus distinct equations were derived for the in vitro digestibility estimation of the samples assayed. The first group included nonprocessed cereal grains and oilseeds, and cereal grain-leguminous seed mixtures. The second group was formed by leguminous seeds, and the third by thermally processed cereal and oilseed products. Although highly significant correlations between in vivo and in vitro estimates for the three groups were found, important differences occurred in the group of processed samples; therefore, more research is required with these types of samples. 相似文献