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排序方式: 共有482条查询结果,搜索用时 15 毫秒
1.
Gin Swen Ham Elise Lahaye Massimiliano Rosso Aurelie Moulins Ellen Hines Paola Tepsich 《水产资源保护:海洋与淡水生态系统》2021,31(8):2257-2277
- Mediterranean fin whales aggregating in the Pelagos Sanctuary in summer to feed are exposed to vessel collision risk, particularly from high-speed ferries.
- This study developed models to predict summer fin whale distribution using a generalized additive model (GAM) and MaxEnt, with the aim of providing a tool to identify potential high whale–ferry collision risk areas along ferry routes within the Pelagos Sanctuary during summertime.
- Models were trained using sightings data collected in the summer months of 2009–2018 on board ferries crossing the central area of the Pelagos Sanctuary. Environmental predictors were bathymetry and mean sea surface chlorophyll concentration of the annual spring bloom period.
- The predictive ability of GAM and MaxEnt was assessed using existing knowledge of summer fin whale distribution in the region. GAM (deviance explained = 20.2%) predictions matched documented distributions more closely than that of MaxEnt, with highest predicted fin whale occurrence in deep offshore waters (>2000 m) encompassing the central north-western and western regions, and in the south-eastern region, consistent with known fin whale habitats within the Pelagos Sanctuary. Inter-annual variability was evident, influencing collision risk areas.
- Collision risk was estimated as a function of the overlap between the predicted probability of fin whale occurrence and ferry density estimated from Automated Identification System data. Ferry routes that cross the northern and eastern regions of the Pelagos Sanctuary presented relatively higher collision risk.
- Areas with changes in risk intensity between the years were temporally and spatially dynamic: some appeared intermittently throughout the study period while others persisted over consecutive years or recurred in different years.
- Due to the vastness of the Pelagos Sanctuary, vessel speed reduction maybe a more practical measure to manage collision risk than re-routing shipping lanes. A combination of Seasonal Management Areas and Dynamic Management Areas approaches could be adopted for high-risk areas.
2.
Diego F. Vasquez Anngie Hernandez Diana Torres Felipe Borrero-Echeverry Paola Zuluaga Diego F. Rincon 《Plant pathology》2022,71(6):1282-1292
Plant–virus interactions are affected by environmental conditions that determine plant vulnerability to pathogens and the population dynamics of insect vectors. We hypothesize that drought enhances horizontal transmission by dampening the basal immunity of plants, which triggers symptom expression and vector manipulation. The potato yellow vein virus (PYVV) causes potato yellow vein disease (PYVD), a re-emerging epidemic of potato crops in South America, and is transmitted horizontally by the greenhouse whitefly (GWF), Trialeurodes vaporariorum (Hemiptera: Aleyrodidae), or vertically through infected seed tubers. We investigated the role of drought and temperature as modulators of PYVD symptom expression, plant immune response, and vector survival, development and host preference. We found that drought induced symptom expression, suppressed the salicylic acid pathway and increased PYVV replication. GWF survival was reduced on PYVV-infected hosts and development was slowest when they fed on plants with PYVD symptoms, which also triggered adults’ attraction to PYVV-infected plants. However, adults previously fed on infected plants showed the opposite effect, being more attracted to PYVV-free plants. We propose a theoretical model that explains the role of drought in modulating potato–PYVV–GWF interactions and provides new insights into plant–virus–vector coevolution. 相似文献
3.
Carlos Magni Paola Poch Betsabé Abarca Iván Grez Eduardo Martínez 《Southern Forests》2019,81(2):103-109
Information on the morphological and physiological responses of seedlings to stressors, such as water stress, is required for successful early establishment of seedlings. We examined provenance variation in morphological and physiological traits of Quillaja saponaria Molina seeds from nine provenances representing a latitudinal transect across the species range in Chile. The seedlings were subjected to two water regimes (well-watered vs water restriction) in a nursery experiment, and growth, biomass, survival, and gas exchange traits were measured. As expected, well-watered seedlings exhibited a superior performance in all traits analysed. Provenance effects were significant for most of the morphological and physiological traits. In the growth and biomass analysis, the northernmost provenance showed the lowest survival, growth and dry biomass, whereas in the gas exchange analysis, the southern interior provenance showed the highest net photosynthesis, transpiration, stomatal conductance and water use efficiency. The interaction between water regimes and provenance was only significant for diameter and net photosynthesis. These results indicate that different provenances of Q. saponaria show a stable performance across different controlled drought conditions. This information is of relevance for sourcing seeds for the restoration of the species. 相似文献
4.
Laura Marconato Carmit Chalfon Riccardo Finotello Gerry Polton Maria E. Vasconi Maurizio Annoni Damiano Stefanello Paola Mesto Ombretta Capitani Chiara Agnoli Maria Amati Silvia Sabattini 《Veterinary and comparative oncology》2019,17(4):537-544
Treatment options for dogs with metastatic (stage III) splenic hemangiosarcoma are limited. A doxorubicin‐based chemotherapy regimen is commonly administered; however, there are no published data to support this practice. The aim of this study was to investigate the impact of maximum‐tolerated‐dose chemotherapy (MTD), metronomic chemotherapy (MC) and no adjuvant treatment on outcome in dogs with stage III splenic hemangiosarcoma undergoing splenectomy. Medical records of dogs with stage III splenic hemangiosarcoma that underwent splenectomy followed by MTD chemotherapy, MC or no adjuvant treatment were retrieved. Time to progression (TTP), survival time (ST) and toxicity were evaluated. One hundred three dogs were identified: 23 received adjuvant MTD, 38 MC and 42 were not medically treated. Overall median TTP and ST were 50 (95% confidence interval [CI], 39‐61) and 55 days (95% CI, 43‐66), respectively. Dogs treated with adjuvant MTD had a significantly longer TTP and ST compared with dogs receiving MC (median TTP, 134 vs 52 days, P = .025; median ST, 140 vs 58 days, P = .023, respectively). Dogs treated by splenectomy only had the shortest median TTP (28 days) and ST (40 days). However, treatment‐related adverse events (AEs) were significantly more frequent in the MTD group (P = .017). The outcome for dogs with metastatic splenic hemangiosarcoma is poor. While MTD showed greater efficacy compared to MC, toxicity was higher in this group. Treatment‐related AEs need to be carefully balanced against this modest survival prolongation when offering adjuvant MTD to dogs with advanced stage hemangiosarcoma. 相似文献
5.
Gabriela Noronha de Toledo Pamela Rodrigues Reina Moreira Daniele Santos Rolemberg Andréia Coutinho Facin Julio Edward Hough Monteiro Mareliza Possa de Menezes Maria Eduarda Bastos Andrade Moutinho da Conceição Felipe Augusto Ruiz Sueiro Rosemeri de Oliveira Vasconcelos Paola de Castro Moraes Mirela Tinucci Costa Andrigo Barboza de Nardi 《Topics in companion animal medicine》2018,33(2):35-39
Osteosarcoma is the most commonly reported bone tumor in dogs, typically affecting the axial and appendicular skeleton. Involvement of the paranasal sinuses and the nasal cavity is extremely rare. This report describes a 6-year-old, female, cross-breed dog presented with signs of 90 days duration and diagnosed with a mass located in the right nasal cavity. Radiography, rhinoscopy, and computed tomography findings suggested the presence of an intranasal tumor. Osteosarcoma in the nasal cavity was diagnosed based on histopathological examination and clinical and imaging findings. Survival time was 12 months from diagnosis. 相似文献
6.
7.
Loss of genetic variability in the captive stocks of tambaqui,Colossoma macropomum (Cuvier, 1818), at breeding centres in Brazil,and their divergence from wild populations 下载免费PDF全文
Jonas da Paz Aguiar Paola Fabiana Fazzi Gomes Igor Guerreiro Hamoy Sidney Emanuel Batista dos Santos Horacio Schneider Iracilda Sampaio 《Aquaculture Research》2018,49(5):1914-1925
The loss of variability in farmed populations and the risks of interactions with wild populations support the need for the genetic monitoring of species farmed throughout the world. In Brazil, the tambaqui is the most widely farmed native fish species. Despite this, there are no data on the pedigree of the farmed stocks, and the potential for interactions with wild populations in the Amazon basin has raised concerns with regard to the genetic variability of these stocks. The present study analysed sequences of the mitochondrial Control Region and 12 microsatellites to characterize the genetic variability of seven historically important commercial tambaqui breeding centres located in four different regions of Brazil, and compared these sequences with those obtained from individuals collected from a wild population. High levels of genetic diversity were found in the wild population, whereas genetic diversity was reduced in both markers in most captive populations, except for the broodstock located near the Amazon River. High FST and DEST indices were recorded between the wild population and most of the captive stocks analysed. The drastic reduction in genetic diversity found in most captive stocks and the difference between these stocks and the wild population may have been the result of the small size of the founding populations and the absence of breeding management. The renewal of the broodstocks and the application of breeding management techniques are recommended. In the Amazon region, in addition, the use of broodstocks that are genetically very different from local wild populations should be avoided. 相似文献
8.
Overall development of a bioprocess for the outdoor production of Nannochloropsis gaditana for aquaculture 下载免费PDF全文
Karina Riveros Claudia Sepulveda Jazmín Bazaes Paola Marticorena Carlos Riquelme Gabriel Acién 《Aquaculture Research》2018,49(1):165-176
In this paper, a systematic methodology is shown for the scaling‐up of Nannochloropsis gaditana production for aquaculture uses. First, an adequate culture medium was developed, prepared using fertilizers instead of pure chemicals. Subsequently, the performance of N. gaditana was modelled as a function of average irradiance; this model being validated in continuous culture experiments. The model was used to determine the optimal dilution rate as well as the expected biomass concentration and productivity at optimal conditions. Finally, outdoor experiments were performed to confirm the model's validity and to determine optimal conditions at real production step. Biomass productivity values of up to 0.08 g L?1 day?1 were obtained at an optimal dilution rate of 0.25 per day in 0.2 m wide flat‐panel reactors using culture medium containing 0.4 g/L NO?3 and 0.034 g/L·PO4?3. Fish trials with Atlantic Salmon demonstrated that the inclusion of produced biomass into fed increase the final weight up to 5%, thus confirming the adequacy of the biomass produced for aquaculture uses. The growth model and the scaling‐up strategy proposed here are necessary to develop real industrial‐scale processes capable of supplying microalgal biomass to the aquaculture markets, which in turn require a guaranteed supply and quality of the raw materials provided. 相似文献
9.
Journal of Plant Diseases and Protection - In 2016, symptoms of stem canker with branches dieback were detected in several Cannabis sativa L. crops, located in the northeast part of Italy (Rovigo... 相似文献