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401.
Detection of Single‐feature Polymorphisms (SFPs) between two tomato varieties and their application in defining the introgressions of resistance loci 下载免费PDF全文
Justyna Milc Alessandro Infantino Maria Aragona Nicola Pecchioni 《Plant Breeding》2015,134(2):226-232
The objectives of the study were to (i) demonstrate that the hybridization data from microarrays can yield information on sequence variation between two inbred lines, an introgression line ‘Mogeor’ and its genetic background ‘Moneymaker’; (ii) characterize, by means of the identified SFPs, the introgressed genomic segments of ‘Mogeor’, carrying resistance genes; and (iii) deliver a set of genetically anchored SFPs potentially useful for breeding. In this work, the GeSNP software was used to identify SFPs in tomato using Affymetrix data from a previous experiment. Sequencing of 12 putative polymorphism‐containing amplicons yielded a SFP probe set validation rate of 90%. In total, 92 Gene Models putatively harbouring SFPs were identified, distributed as following: 61 Gene Models on chromosome 9, and one to eight on the remaining tomato chromosomes apart from chromosomes 7, 8 and 12. Newly discovered SFPs from microarray data can thus provide not only useful information for definition of introgressed genomic regions, but also identification of candidate genes and new markers for MAS. 相似文献
402.
Otranto D Lia RP Agostini A Traversa D Milillo P Capelli G 《Preventive veterinary medicine》2005,69(1-2):153-159
Bovine hypodermosis is a myiasis caused by Hypoderma bovis and Hypoderma lineatum (Diptera, Oestridae) larvae, which has a severe economic impact on the livestock industry. Though myiasis is widespread throughout Italy, no nationwide eradication program has ever been planned, unlike in other European Countries. With a view to setting up a national control program, a pilot study was carried out in Southern Italy on 9939 cattle bred in an area with a high prevalence of cattle hypodermosis, using moxidectin 0.5% pour-on (Cydectin, Fort Dodge) and 1% injectable (Cydectin, Fort Dodge) formulations. At the recommended dosage, moxidectin displayed efficacy levels of 99.9% in the pour-on and 100% in the injectable formulation, whereas the microdose (1 mg per head regardless of body weight) was less effective (65.7%). This trial contributed to a significant reduction in infestation rates in the study area and represented the first step through which a national program for eradicating warble fly infestation in Italy. 相似文献
403.
Ascribing Ecological Meaning to Habitat Shape by Means of a Piecewise Regression Approach to Fractal Domains 总被引:1,自引:0,他引:1
Alessandro?Ferrarini Pierfrancesca?Rossi Orazio?Rossisgtpm@libero.it" title="o.rossi@unipr.it sgtpm@libero.it" itemprop="email" data-track="click" data-track-action="Email author" data-track-label="">Email author 《Landscape Ecology》2005,20(7):799-809
A fractal dimension (FD) indicates the ability of a set of structures to fill the Euclidean space where it is embedded. For habitat boundaries, FD is bound to a plane, thus 1 ≤ FD ≤ 2. FD is low for simple shapes and increases as patches become more irregular. Some authors have found that FD metric delineating area-perimeter relation (APR) is best fitted through piecewise linear curves, where the slope of each line segment is one-half the FD over the corresponding scaling region. The detection of shifts in boundary FD of landscape habitats is a significant issue in ecology, since discontinuities could be an index of a substantial modification of the processes and dynamics that generate and maintain habitats. This work makes use of fractal analysis to examine the relationship between anthropogenic processes and habitat spatial patterns. It proposes two goals (1) suggesting Multivariate Adaptive Regression Splines (MARS®) as a fast and effective approach to discover shifts in APR of landscape patches; (2) explaining the substantial existence of such shifts using a set of human-related predictor variables. MARS methodology has been applied to 6 types of habitats within the Baganza stream watershed (Parma, Italy) and the discovered patterns have been correlated with anthropogenic variables that could influence APR. A standardized linear discriminant analysis (DA) has been used to predict FDs from the set of the employed predictors. DA corroborated the existence of breakpoints in APR and explained the contribute of predictor variables in determining the discovered shifts. 相似文献
404.
Borrelli L Fioretti A Ruggiero V Santaniello A Cringoli G Ricci A Barco L Menna LF Dipineto L 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(3):385-387
A total of 1,000 rectal samples were collected from rabbits coming from 25 rabbit farms in southern Italy. All samples were processed for isolation of Salmonella spp. by standard culture method based on the ISO 6579:2002 method. Salmonella spp. was isolated from 1/25 rabbit farms analyzed. In particular, four out of 1,000 rectal swab samples, taken from young rabbits, were serotyped as S. Typhimurium and phage typed as S. Typhimurium DT104. All the isolates were resistant to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline (ACSSuT pentaresistance type). The findings of the present study suggest the rabbit as potential carrier of S. Typhimurium DT104. 相似文献
405.
Antonello Sala Joana dArc Prat Farran Josefina Antonijuan Alessandro Lucchetti 《Fisheries Research》2009,100(2):156-166
A new door has been designed to reduce hydrodynamic drag coefficient and increase spread of door commonly used in the Mediterranean commercial demersal trawl fisheries. Flume tank testing and engineering sea trials provide data which allow us to illustrate the performance and impact on the seabed of an existing door and a new door design. In the flume tank, each model was tested over a range of attack angles and for a limited range of otterboard heels. Curves of spreading-, drag- and down-force coefficients have been calculated. In the case of sea trials in order to extract the hydrodynamic coefficients an analysis has been applied and a mathematical model was used to calculate attack angle functions. From analysing the differences between engineering sea trials and flume tank tests we have deduced some conclusions about additional ground contact forces on sea trials that affect the performance of the doors. Moreover, a comparison between reaction forces of the flume tank and the estimation of reaction forces at sea has been given. Finally, this study allowed us to notice important differences between traditional and experimental otterboards. 相似文献
406.
407.
Paolo Casale Amedeo Ciccocioppo Giulia Vagnoli Alessandro Rigoli Daniela Freggi Livia Tolve Paolo Luschi 《水产资源保护:海洋与淡水生态系统》2020,30(1):123-130
- Spatio‐temporal distribution is fundamental information for species of conservation concern, like sea turtles, that are threatened by anthropogenic activities at sea such as fishing. While coarse‐scale distribution information is available for several sea turtle populations, fine‐scale distribution informing on hot‐spot areas for spatial management is more difficult to obtain.
- Here a citizen science approach involving tourism boats was undertaken to investigate the spatio‐temporal distribution of the loggerhead sea turtle (Caretta caretta) in the Pelagie Archipelago, located in a major foraging area for this species in the Mediterranean and where high fishing‐induced mortality occurs. The study was designed to provide data of absence and total sampling effort, commonly under‐reported in citizen science studies, allowing comparison among zones and periods. This was complemented by reports from fishing vessels.
- Tourism boats reported 584 loggerhead turtle sightings during 1718 daily trips and fishing vessels reported 280 loggerhead turtles captured during 1040 fishing days. The results indicate a strong heterogeneous distribution in the Archipelago, with a low turtle occurrence around the main island, Lampedusa, where the highest human presence and activity occur. This may represent rare evidence of displacement behaviour of turtles that is worth further investigation. This also suggests that the current small marine protected area around Lampedusa has a low conservation impact. Zones with higher loggerhead turtle occurrence appear to be in the south and the west parts of the Archipelago, suggesting that spatial management would be possible when relatively small hot‐spots have been identified through specific surveys.
- This study shows the potential of citizen science for providing preliminary information to guide more demanding and specific investigations. Such an approach may tremendously and rapidly improve the current knowledge on fine‐scale sea turtle distribution in regions with a great extension of coastlines and intensive tourist activities, such as the Mediterranean.
408.
Antonello Sala Alessandro Lucchetti Corrado Piccinetti Mario Ferretti 《Fisheries Research》2008,93(1-2):8-21
Mediterranean demersal trawl fisheries traditionally operate using small diamond-shape meshes in the codend, which tend to retain almost all animals. We investigated the effect of mesh configuration on the size selectivity of nine species (the scaldfish Arnoglossus laterna, the broad-tail shortfin squid Illex coindettii, the European hake Merluccius merluccius, the red mullet Mullus barbatus, the Norway lobster Nephrops norvegicus, the common pandora Pagellus erythrinus, the deepwater rose shrimp Parapenaeus longirostris, the Mediterranean horse mackerel Trachurus mediterraneus and the poor-cod Trisopterus minutus capelanus) commonly captured in the Mediterranean demersal trawls. Two codends having meshes with the same opening (ca. 38 mm) but different mesh configuration (DM38: diamond-mesh and SM38: square-mesh configuration) were fished daily and alternately on the same trawl. They demonstrated a substantial improvement in selectivity with square-mesh. Selectivity was measured using the covered codend technique, the cover being supported by circular hoops.The results were analysed taking into account the between-haul variation in selectivity. Two other important external variables were identified: the trawling depth and the codend catch, which for some species influenced between-haul variation, but there was no evidence of a coherent effect on selectivity parameters.The selectivity of 40 mm diamond-mesh codend has been reported to be rather poor because a large proportion of the codend catch is immature and smaller than the minimum landing size (MLS) or first maturity size. With the exception of the flatfish (A. laterna), the effect of a change of mesh configuration from diamond- to square-mesh on size selectivity positively affected the retention length at 50% (L50). However, square-meshes were found to be unsuitable for flat and/or deep-bodied fish as these escape more readily from diamond-meshes.The Council Regulation (EC) No. 1967/2006, concerning management measures for the sustainable exploitation of fishery resources in the Mediterranean, establishes the MLS of marine organisms. However, the increase in L50 with square-mesh would not avoid some of the existing contradictions in allowing the use of codend mesh which leads to lower L50 than the MLS. 相似文献
409.
Kåre Nolde Nielsen Michaela Maria Aschan Sveinn Agnarsson Marta Ballesteros Alan Baudron Maria de Fátima Borges Aida Campos Rosa Chapela Anna Kristín Daníelsdóttir Karim Erzini Ólavur Gregersen Petter Holm Alessandro Lucchetti Sveinn Margeirsson Hugo Vilela Mendes Petter Olsen Mafalda Rangel Antonello Sala José Luis Santiago Sigríður Sigurðardóttir Cristina Silva Daryl Sykes Jónas Rúnar Viðarsson Massimo Virgili Laura Wise Paul George Fernandes 《Fish and Fisheries》2018,19(2):363-376
We present a framework for results‐based management (RBM) of commercial fisheries. The core idea of RBM is to reduce micromanagement by delegating management responsibility to resource users. The RBM framework represents an industrial organization approach to co‐management and comprises three defining processes, conducted by three independent “agents”: (i) an “authority” defines specific and measurable and achievable objectives (outcome targets, OTs) for the utilization of fisheries resources, (ii) resource user organizations (termed “operators”) take responsibility for achieving these OTs and provide documentation that (iii) allows independent “auditors” to evaluate the achievement of OTs. Using incentive mechanisms, notably deregulation, RBM grants operators the flexibility to develop and implement innovative and cost‐effective ways to achieve OTs. The feasibility of implementing RBM in five European fisheries was investigated in cooperation with relevant stakeholders through artificial planning processes and computer simulations. The operators involved were enthusiastic, and new management plans were drafted based on the framework. These included socioeconomic OTs in addition to traditional stock objectives, encompassing an ecosystem approach. Several issues are in need of further research to consolidate the approach and prepare the ground for practical implementation, including: the specification of the legal and regulatory framework required to underpin RBM, details of transitional arrangements when shifting towards RBM (including cost‐sharing) and the development of necessary organizational capacity for operators. Initially, we therefore envisage the framework being applied to high‐value single‐species fisheries, with a limited number of participants, which are adequately represented by a competent organization. 相似文献
410.
Paolo Guidetti Piero Addis Fabrizio Atzori Simona Bussotti Antonio Cal Alessandro Cau Jean‐Michel Culioli Giuseppe De Lucia Antonio Di Franco Manfredi Di Lorenzo Maria Cristina Follesa Vittorio Gazale Giorgio Massaro Francesco Mura Augusto Navone David Pala Pier Augusto Panzalis Antonio Pusceddu Alberto Ruiu Angelo Cau 《水产资源保护:海洋与淡水生态系统》2019,29(4):537-545