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111.
112.
Joan Marull Carme Font Enric Tello Nofre Fullana Elena Domene Manel Pons Elena Galán 《Landscape Ecology》2016,31(2):317-336
Context
The role of agricultural landscapes in biodiversity conservation is an emerging topic in a world experiencing a worrying decrease of species richness. Farm systems may either decrease or increase biological diversity, depending on land-use intensities and management.Objectives
We present an intermediate disturbance-complexity model (IDC) of cultural landscapes aimed at assessing how different levels of anthropogenic disturbance on ecosystems affect the capacity to host biodiversity depending on the land matrix heterogeneity. It is applied to the Mallorca Island, amidst the Mediterranean biodiversity hotspot.Methods
The model uses the disturbance exerted when farmers alter the Net Primary Production through land-use change as well as when they remove a share of it (HANPP), together with Shannon–Wiener index (H′) of land-cover diversity. The model is tested with a twofold-scalar experimental design (1:50,000 and 1:5000) of a set of landscape units along three time points (1956, 1989, 2011). Species richness of breeding and wintering birds, taken as a biodiversity proxy, is used in an exploratory factor analysis.Results
The results clearly show that when intermediate levels of HANPP are performed within intermediate levels of complexity (H′) in landscape patterns, like agro-forest mosaics, great bird species richness and high socio-ecological resilience can be maintained. Yet, these complex-heterogeneous landscapes are currently vanishing due to industrial farm intensification, rural abandonment and urban sprawl.Conclusions
The results make apparent the usefulness of transferring the concept of intermediate disturbance-complexity interplay to cultural landscapes. Our spatial-explicit IDC model can be used as a tool for strategic environmental assessment of land-use planning.113.
A severe crown rot of pear trees of cultivar ‘Kondoula’ grafted on quince rootstock was observed in Greece. Isolations from
the affected tissues repeatadly yielded aPhytophthora sp. that was determined by morphological and physiological characteristics to beP. citrophthora. The pathogenicity of two of theP. citrophthora isolates was tested by inoculating trunks of 2-year-old pear trees by mycelial agar disks. Thirty-two days after inoculation
all inoculated trees were infected. Although the pear isolates could not be differentiated from isolates ofP. palmivora orP. nicotianae based on isozyme profiles of α-esterase or lactate dehydrogenase, RAPD profiles with one selected primer differentiated the
pear isolates from the other species and revealed an electrophoretic banding pattern similar to that of aP. citrophthora standard. This is the first report ofP. citrophthora on pear trees in Greece. 相似文献
114.
Robles Esperanza Ramírez Pedro Elena González Ma. de Guadalupe Sáinz Ma. Martínez Blanca Durán Angel Elena Martínez Ma. 《Water, air, and soil pollution》1999,113(1-4):217-226
Bacteriological and physico-chemical parameters of 265 samples from 39 brands sold in 5-gallon plastic and glass bottles and 2-5 L plastic containers were analyzed to determine the quality of bottled water distributed in Mexico City. Tests included fecal and total coliform counts, alkalinity, total hardness, chloride, calcium and magnesium concentrations, pH and conductivity. Correlation and cluster analyses and ANOVA were carried out, and a comparison made of the averages with the maximum permissible levels established in the Official Mexican Norms. Concerning the investigated parameters no differences (p > 0.05) between the brands were found. Physico-chemical parameters were studied and all the samples were within the permissible limits. Most samples taken from the 5-gallon containers exceeded the maximum bacteriological limits. It was concluded that the bacteriological quality of the brands studied was extremely variable. Appropriate sanitary measures, should be established to control this aspect. 相似文献
115.
Donatella Lotti DVM PhD Maria Tresa Capucchio DVM Elena Gaidolfi DM Monica Merlo DVM 《Veterinary radiology & ultrasound》1999,40(6):622-626
A 5-year-old, male Yorkshire Terrier had chronic and progressive neurologic signs compatible with lesions in the right brain stem and right forebrain. In magnetic resonance images of the brain there were multifocal lesions at different stages of evolution, consistent with an inflammatory disease. The lesions were located in the white matter of the cerebrum, in the diencephalon and mesencephalon. These lesions were hypointense in T1-weighted images and hyperintense in T2-weighted images with no mass effect and minimal enhancement with gadolinium. Necrotizing encephalitis was confirmed post mortem. 相似文献
116.
Victor Manuel Ocaño‐Higuera Alfonso Nivardo Maeda‐Martínez María Elena Lugo‐Sánchez Gillermina García‐Sánchez Enrique Márquez‐Ríos Silvia Gómez‐Jimenez Ramón Pacheco‐Aguilar 《Aquaculture Research》2011,42(8):1087-1095
Currently, there is an increasing interest in shipping live adult scallops to markets and broodstock to hatcheries; nevertheless, information about the shipping effect on live scallops physiology is very scarce. In a previous study, a method in emersion was developed to ship scallop seed out of water, but it was not known whether this method is useful to transport adult organisms. As a consequence, the purpose of this study was to evaluate the effects of transportation by the emersion method on the physiological status of the adductor muscle of adult giant lion's paw scallop. Live specimens were packaged in a container and transported in emersion for 11 h. Six scallops were frozen in a farm and a similar number were frozen as soon as they arrived to the laboratory. Physiological indices were determined in each lot and the survival was estimated 24 h after re‐immersion. As a result of the transportation, a significant loss (P<0.05) of total carbohydrates, glycogen, adenosine 5′‐triphosphate and adenilated energetic charge, and a significant increase (P<0.05) in the free amino acids concentration were observed. Eighty‐eight per cent survival was achieved; therefore, we conclude that this method is appropriate for shipping live adult scallops of Nodipecten subnodosus. 相似文献
117.
118.
Antioxidant activity and lipid peroxidation in Artemia nauplii enriched with DHA‐rich oil emulsion and the effect of adding an external antioxidant based on hydroxytyrosol 下载免费PDF全文
Elena Viciano Óscar Monroig Carlos Barata Carlos Peña Juan Carlos Navarro 《Aquaculture Research》2017,48(3):1006-1019
Artemia nauplii catabolize polyunsaturated fatty acids (PUFA); in particular, they retroconvert docosahexaenoic acid (DHA, 22:6n‐3), so enrichment is a continuous quest towards increasing PUFA through the use of PUFA‐rich enrichment products. However, optimal conditions during enrichment (aeration, illumination and temperatures around 28°C) tend to accelerate autoxidation of PUFA and the formation of potentially toxic oxidation products. Water‐soluble antioxidants like the polyphenolic compound hydroxytyrosol (3,4‐dihydroxyphenylethanol), a polar molecule found in the water fraction resulting after the milling process of olives, arise as promising compounds to prevent oxidation during Artemia enrichments. We investigated the antioxidant activity and lipid peroxidation in Artemia nauplii during enrichment and the effect of adding an external antioxidant based on hydroxytyrosol during the enrichment with a PUFA‐rich emulsion (M70). For this purpose, the activity of antioxidant enzymes (catalase, superoxide dismutase, glutathione‐S‐transferase, glutathione peroxidase), as well as lipid peroxidation, was determined in enriched and unenriched Artemia nauplii. To validate antioxidant activity and lipid peroxidation, in a first experiment, nauplii were enriched with microalgae (Tetraselmis suecica), yeast (Saccharomyces cerevisiae) and M70 emulsion. In a second experiment, enrichment with a commercial emulsion (DC Super Selco), M70, and a combination of M70 and hydroxytyrosol (Hytolive, HYT) added as an external antioxidant were performed. The combination of M70 with HYT produced the best results, in terms of activity of antioxidant enzymes. The analysis of the fatty acids from total lipids showed that the addition of hydroxytyrosol preserved the DHA percentage of enriched nauplii. 相似文献
119.
Aeromonas spp. are generally found in aquatic environments, although they have also been isolated from both fresh and processed food. These Gram-negative, rod-shaped bacteria are mostly infective to poikilothermic animals, although they are also considered opportunistic pathogens of both aquatic and terrestrial homeotherms, and some species have been associated with gastrointestinal and extraintestinal septicemic infections in humans. Among the different pathogenic factors associated with virulence, several cell-surface glucans have been shown to contribute to colonization and survival of Aeromonas pathogenic strains, in different hosts. Lipopolysaccharide (LPS), capsule and α-glucan structures, for instance, have been shown to play important roles in bacterial–host interactions related to pathogenesis, such as adherence, biofilm formation, or immune evasion. In addition, glycosylation of both polar and lateral flagella has been shown to be mandatory for flagella production and motility in different Aeromonas strains, and has also been associated with increased bacterial adhesion, biofilm formation, and induction of the host proinflammatory response. The main aspects of these structures are covered in this review. 相似文献
120.
Rubn Alonso Contreras‐Tapia María Elena Castellanos‐Pez S. Nandini Marcela Ivonne Benítez‐Díaz‐Mirn Gabriela Garza‐Mourio 《Aquaculture Research》2020,51(5):2102-2111
The effect of a commercial probiotic (NanoCrusta, Altacrusta, Mexico City, Mexico) on the growth performance of Brachionus calyciflorus Pallas, 1766, was evaluated. In a first approach, probiotics were supplied in four densities (2.0 × 103, 1.1 × 105, 2.1 × 105 and 2.1 × 106 cells/ml), alone and in combination with Chlorella vulgaris (1 × 106 cells/ml). The test rotifer did not grow on the probiotic alone. However, when probiotics + C. vulgaris were added, the maximum densities (Dmax; ind/ml) and population growth rates (r) observed were higher. In the second experiment, probiotics were supplied at five higher densities (2.1 × 106, 4.2 × 106, 8.5 × 106, 1.7 × 107 and 3.4 × 107 cells/ml) with C. vulgaris and a control treatment with only C. vulgaris (probiotic‐free). Treatments supplied with probiotics between 2.1 × 106 and 1.7 × 107 cells/ml showed significantly higher Dmax and r than the control treatment. The results showed a positive effect of probiotic bacteria when supplied with C. vulgaris. The best outcome showed a Dmax 2.16 times and an r 1.63 times higher than the density of the control treatment. Growth rates were higher in the treatments with probiotics compared to the control. We conclude that application of NanoCrusta is feasible to improve B. calyciflorus production, but the effects need to be tested in larger scales. 相似文献