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371.
Priscilla Bettini Rita Baraldi Francesca Rapparini Lorenzo Melani Maria Luisa Mauro Daniela Bindi Marcello Buiatti 《Scientia Horticulturae》2010
In the present paper we report on the effects of the insertion of the Agrobacterium rhizogenes rolC gene in the tomato (Solanum lycopersicum L., formerly Lycopersicon esculentum Mill.) cultivar Tondino. Several transgenic lines were successfully obtained, between which two clones, rolC1 and rolC3, were chosen for the analysis of morpho-productive traits as well as of the endogenous levels of auxin and abscisic acid. Consistent with the known phenotypic effect of this gene, the transformed tomato plants were significantly shorter than the corresponding controls. On the other hand, even if yield was not affected by the transformation in terms of average number of fruits produced, fruit weight was significantly lower in the transgenics with respect to the controls. Therefore, insertion of the rolC gene does not lead to an improvement in plant productivity. 相似文献
372.
Clive A. McAlpine Leonie M. Seabrook Jonathan R. Rhodes Martine Maron Carl Smith Michiala E. Bowen Sarah A. Butler Owen Powell Justin G. Ryan Christine T. Fyfe Christine Adams-Hosking Andrew Smith Oliver Robertson Alison Howes Lorenzo Cattarino 《Landscape Ecology》2010,25(8):1155-1168
The need to avert unacceptable and irreversible environmental change is the most urgent challenge facing society. Landscape ecology has the capacity to help address these challenges by providing spatially-explicit solutions to landscape sustainability problems. However, despite a large body of research, the real impact of landscape ecology on sustainable landscape management and planning is still limited. In this paper, we first outline a typology of landscape sustainability problems which serves to guide landscape ecologists in the problem-solving process. We then outline a formal problem-solving approach, whereby landscape ecologists can better bring about disciplinary integration, a consideration of multiple landscape functions over long time scales, and a focus on decision making. This framework explicitly considers multiple ecological objectives and socio-economic constraints, the spatial allocation of scarce resources to address these objectives, and the timing of the implementation of management actions. It aims to make explicit the problem-solving objectives, management options and the system understanding required to make sustainable landscape planning decisions. We propose that by adopting a more problem-solving approach, landscape ecologists can make a significant contribution towards realising sustainable future landscapes. 相似文献
373.
Borruso Luigimaria Esposito Alfonso Bani Alessia Ciccazzo Sonia Papa Marianna Zerbe Stefan Brusetti Lorenzo 《Journal of Soils and Sediments》2017,17(1):253-265
Journal of Soils and Sediments - Spatial distribution on a regional scale of the rhizobacterial communities of Phragmites australis stands was investigated along the Yellow River watershed, China.... 相似文献
374.
After the development of the gastric function in juvenile fish, dietary proteins enter a two-phase digestive process comprising an acidic gastric phase followed by an alkaline intestinal phase. However, the main gastric protease, pepsin, is strictly dependent on the existence of a low-enough environmental pH. In 20-g gilthead sea bream, Sparus aurata, the mean minimal gastric pH is close to 4.5, while the mean pH in the duodenal portion of the intestine was nearly fixed at 6.5. The mean maximal gastric content of HCl was approximately 20 microEq for a low-buffering diet. Gastric proteases were more severely affected than intestinal proteases when assayed at actual sub-optimal pH values, 4.5 and 6.5, respectively. When the gastric proteases of juvenile fish were pre-incubated with a citric acid buffer at pH 6.0, the activity at pH 4.5 was very low, whereas when they were pre-incubated with the same buffer at pH 3.0, the activity at pH 4.5 was significantly increased; this fact suggests a deficient activation of zymogens during the gastric digestion and points to a potential approach to improve protein digestion in juvenile gilthead sea bream. 相似文献
375.
Núria Busquets Joaquim Segalés Lorena Córdoba Tufaria Mussá Elisa Crisci Gerard E. Martín-Valls Meritxell Simon-Grifé Marta Pérez-Simó Monica Pérez-Maíllo Jose I. Nú?ez Francesc X. Abad Lorenzo Fraile Sonia Pina Natalia Majó Albert Bensaid Mariano Domingo María Montoya 《Veterinary research》2010,41(5)
The recent pandemic caused by human influenza virus A(H1N1) 2009 contains ancestral gene segments from North American and Eurasian swine lineages as well as from avian and human influenza lineages. The emergence of this A(H1N1) 2009 poses a potential global threat for human health and the fact that it can infect other species, like pigs, favours a possible encounter with other influenza viruses circulating in swine herds. In Europe, H1N1, H1N2 and H3N2 subtypes of swine influenza virus currently have a high prevalence in commercial farms. To better assess the risk posed by the A(H1N1) 2009 in the actual situation of swine farms, we sought to analyze whether a previous infection with a circulating European avian-like swine A/Swine/Spain/53207/2004 (H1N1) influenza virus (hereafter referred to as SwH1N1) generated or not cross-protective immunity against a subsequent infection with the new human pandemic A/Catalonia/63/2009 (H1N1) influenza virus (hereafter referred to as pH1N1) 21 days apart. Pigs infected only with pH1N1 had mild to moderate pathological findings, consisting on broncho-interstitial pneumonia. However, pigs inoculated with SwH1N1 virus and subsequently infected with pH1N1 had very mild lung lesions, apparently attributed to the remaining lesions caused by SwH1N1 infection. These later pigs also exhibited boosted levels of specific antibodies. Finally, animals firstly infected with SwH1N1 virus and latter infected with pH1N1 exhibited undetectable viral RNA load in nasal swabs and lungs after challenge with pH1N1, indicating a cross-protective effect between both strains. 相似文献
376.
Lorenzo Gonz��lez Stuart Martin Stephen A.C. Hawkins Wilfred Goldmann Martin Jeffrey S��lvia Sis�� 《Veterinary research》2010,41(4)
After detection of a high prevalence of scrapie in a large dairy goat herd, 72 infected animals were examined by immunohistochemistry with prion protein (PrP) antibody Bar224 to study the pathogenesis of the infection. Tissues examined included the brain and thoracic spinal cord (TSC), a wide selection of lymphoreticular system (LRS) tissues, the distal ileum and its enteric nervous system (ENS), and other organs, including the mammary gland. The whole open reading frame of the PRNP gene was sequenced and antibodies to caprine arthritis-encephalitis virus (CAEV) infection were determined. Unexpectedly, accumulation of disease-associated PrP (PrPd) in the brain was more frequent in methionine carriers at codon 142 (24/32, 75.0%) than amongst isoleucine homozygotes (14/40, 35.0%). The latter, however, showed significantly greater amounts of brain PrPd than the former (average scores of 9.3 and 3.0, respectively). A significant proportion of the 38 goats that were positive in brain were negative in the ENS (44.7%) or in the TSC (39.5%). These results, together with the early and consistent involvement of the circumventricular organs and the hypothalamus, point towards a significant contribution of the haematogenous route in the process of neuroinvasion. Chronic enteritis was observed in 98 of the 200 goats examined, with no association with either scrapie infection or presence of PrPd in the gut. Lymphoproliferative interstitial mastitis was observed in 13/31 CAEV-positive and scrapie-infected goats; PrPd in the mammary gland was detected in five of those 13 goats, suggesting a possible contribution of CAEV infection in scrapie transmission via milk. 相似文献
377.
A case of an adult dog with multifocal, progressive neurological signs caused by Neospora caninum is reported. Pathological studies showed cerebellar lesions due to the parasite, which was also present in other parts of the nervous system and muscle. Cerebellar atrophy related to Neospora infection has been rarely reported in veterinary medicine, and has been shown to affect ruminants and dogs. The cerebellar involvement and the age of the present dog make this case uncommon. 相似文献
378.
Ciceroni L Fabbi M Ciarrocchi S Pinto A Ciervo A Kasten RW Chomel BB 《Comparative immunology, microbiology and infectious diseases》2002,25(4):217-228
Bartonella henselae has been identified and characterized for the first time in Italy. A strain, designed Pavia-1, was isolated from the blood of a cat whose owner developed cat scratch disease (CSD). Pavia-1 and two American B. henselae strains (Houston-1, ATCC 49882, type I and strain 269608, UC Davis, type II) were compared by whole-cell fatty analysis (CFA), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) for protein profiles, Western immunoblotting (WB) for reactivity with polyclonal antibodies, polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), type-specific 16S rRNA PCRs, and pulsed-field gel electrophoresis (PFGE). Bartonella clarridgeiae (ATCC 51734) was also included for comparison. Pavia-1 was identified as a B. henselae type I. PFGE allowed differentiation between B. clarridgeiae and B. henselae and furthermore, between all the B. henselae strains. The fingerprints of PFGE observed for Pavia-1 were distinct from those of B. henselae type II and also of Houston-1, suggesting that the two type I strains derived from two different clones. These results show the capability of B. henselae to develop genotypic variability between genetically related strains. 相似文献
379.
Lorenzo Cruces Myriam Rodríguez Óscar Monterroso Omar Álvarez Óscar Pérez Rodrigo Riera 《水产资源保护:海洋与淡水生态系统》2024,34(3):e4090
- This study analysed the catches of trap fishing in the Canary Archipelago, NE Atlantic Ocean. This study was conducted from October 2016 to September 2017, April to November 2018 and September 2020, in five ports (San Cristóbal, Taliarte, Castillo del Romeral, Arguineguín and Mogán).
- The primary gear were traps with small mesh size (31.6 mm) and large mesh size (50.8 mm). A total of 2587 small mesh size traps and 141 large mesh size traps were analysed from 20- to 130-m depth.
- The main target species were Dentex gibbosus and Stephanolepis hispidus.
- Catches of traps with large mesh size showed D. gibbosus above first maturity and S. hispidus in small mesh size traps. Both species exhibit larger specimens during reproductive periods.
- The most effective traps for D. gibbosus (large mesh) were located on the western coast (>30-m depth), with the highest catch per unit of effort (CPUE) in Mogán (857.7 g trap−1 day−1). The most effective traps for S. hispidus (small mesh) were located in southern areas, especially in sandy habitats (124.9 g trap−1 day−1 in Castillo del Romeral, 102.9 g trap−1 day−1 in Arguineguín).
- The highest catchability of D. gibbosus was observed in April (CPUE of 962.8 g trap−1 day−1), and the highest catchability of S. hispidus was found in June (CPUE of 165.9 g trap−1 day−1).
- The traps with small mesh size showed a great selectivity of sizes for S. hispidus; though high catch rates of immature specimens of D. gibbosus pose a threat to species conservation.
- The management recommendations' proposed measures include revising minimum catch sizes for both species. Additionally, we suggested depth limitations for mesh sizes of traps.
- The study highlights the need for new management strategies to ensure the conservation of targeted demersal species, with special emphasis on addressing the threat posed by small mesh sizes to immature D. gibbosus.
- The findings provide valuable insights for adapting fishery management practices to sustainably conserve the targeted species in the Canary Archipelago.
380.
Lorenzo Vilizzi Shaun N. Meredith Clayton P. Sharpe Rohan Rehwinkel 《Fisheries Research》2008,93(1-2):146-153
Amongst passive collecting gear types, light traps have been used extensively to sample the larvae and juveniles of fish in both marine and freshwater environments, and especially so in structurally complex habitats. Although a number of modifications have been proposed to increase efficiency, no account has hitherto been made of the possible loss of trapped larvae and juveniles as a result of within-trap predation by piscivorous fish. To address this issue, we evaluated the efficiency of modified light traps by the addition of mesh (3 mm knot-to-knot wrapped around the entrance chambers), by combining results from a long-term monitoring study with those from a designed field experiment. Abundance of larvae and juveniles collected during the monitoring program was higher in the years following mesh application (hence, beyond monthly variation), and this was supported by the experiment. Based on the latter, light/mesh traps consistently caught only larvae/juveniles, hence excluding adults; whereas the opposite was true of the light/no-mesh trap combination. Also, mesh/no-light traps did not capture any fish, unlike no-mesh/no-light traps, which sampled only adults. Our findings suggest that in situ predation on larvae and juveniles within light traps should not be overlooked. The occurrence of piscivorous and cannibalistic behaviour in Hypseleotris spp. is also discussed. 相似文献