Three dimensional ultra-high-density electro-anatomical cardiac mapping in horses: methodology     

Glenn Van Steenkiste  Dominique De Clercq  Tim Boussy  Lisse Vera  Stijn Schauvliege  Annelies Decloedt  Gunther van Loon 《Equine veterinary journal》2020,52(5):765-772

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Conservation of Amazonian aquatic mammals     

Sannie Brum  Patrícia Rosas-Ribeiro  Rodrigo de Souza Amaral  Diogo Alexandre de Souza  Leandro Castello  Vera Maria Ferreira da Silva 《水产资源保护:海洋与淡水生态系统》2021,31(12):1068-1086

1. Aquatic mammals worldwide are highly threatened in freshwater ecosystems where they are affected by direct human activities (e.g. hunting) as well as indirect human alteration of freshwater ecosystems (e.g. dams, mining activity). Although aquatic mammals of the Amazon Basin are experiencing many growing threats, little is known about the escalating impacts on them, current limitations in protection mechanisms, and possible strategies to ensure their conservation. This study synthesizes the available information on Amazonian aquatic mammals, including the ecological characteristics of these species, key threats, population status and conservation prospects.
2. Amazonian aquatic mammals comprise seven species – Inia geoffrensis, Inia boliviensis, Inia araguaiaensis, Sotalia fluviatilis, Trichechus inunguis, Pteronura brasiliensis and Lontra longicaudis – which are characterized by low reproductive rates and keystone ecosystem roles. These species are endangered mainly by biological resource use, natural ecosystem modifications, energy production and mining, and climate change. Although information is sparse, there is evidence that these threats are inducing population declines of Inia spp., and hindering the recovery of populations of P. brasiliensis.
3. Protection mechanisms for these species mostly include national and international laws and agreements, legislation governing environmental licensing and protected areas. Each of these protection mechanisms, however, has limited capacity to protect Amazonian aquatic mammals, largely because they are poorly enforced, lack transnational coordination or require population trend data that do not exist.
4. Reversing the current state of affairs for Amazonian aquatic mammals requires an integrated research and policy approach that, at a minimum, substantially increases the present capacity to monitor their population responses to human impacts, establishes effective enforcement of existing legislation and prevents further impacts from hydropower development. To implement such an approach, information on the ecology of these species is necessary to create public and scientific awareness.

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Comparison of freshwater and marine performances of all‐female diploid and triploid Atlantic salmon (Salmo salar L.)     

Deirdre Cotter  Vera O'Donovan  Alan Drumm  Nicola Roche  E Nigel Ling  & Noel P Wilkins 《Aquaculture Research》2002,33(1):43-53

The performance of all‐female diploid (AF2N) and triploid (AF3N) Atlantic salmon were compared in fresh water, under commercial production conditions in 1995 and 1996 year classes. The performance of the 1996 year class was also assessed for 14 months in a commercial sea farm. Freshwater mortality was higher in the triploid groups. The majority of losses occurred in the early stages of egg development and during the first feeding period, when the incidence of non‐feeding fry was consistently higher. In growth studies, although diploid fry were significantly heavier during first feeding there were no significant differences in weight between groups some 8 months after fertilization or in presmolt growth periods from February to April in 1996 and 1997. Smolting rates were high (range 93.5–95.3%) and the incidence of deformities was low (< 1%) in both groups. Marine survival was lower in the triploid group, largely as a consequence of higher losses sustained during a period of chronic stress, when triploid losses were 9% higher. Growth patterns were similar for the first 11 months in sea water. Although graded triploid salmon were heavier in January 1998 (AF3N 1.62 ± 0.033 kg, AF2N 1.46 ± 0.36 kg, P < 0.05), when the fish were harvested in May 1998 diploid salmon were significantly heavier than triploid salmon although there was no significant difference in weights after evisceration (AF3N 2.40 kg ± 0.04 AF2N 2.49 kg ±0.03). The increase in weight of the diploids between winter and harvest reflects the growth spurt that occurs in maturing fish in the spring. Overall yields of triploid salmon in salt water were lower as a result of inferior survival.  相似文献   

Self-inhibition of spore germination via reactive oxygen in the fungus Cladosporium cucumerinum, causal agent of cucurbit scab     

Andrey A. Aver��yanov  Vera P. Lapikova  Tatiana D. Pasechnik  Tatiana S. Zakharenkova  Con Jacyn Baker 《European journal of plant pathology / European Foundation for Plant Pathology》2011,130(4):541-550

Cladosporium cucumerinum spore germination in vitro depended on spore suspension density. Different fungal isolates displayed germination maxima at different spore concentrations. For one isolate, the maximum was observed at the same spore density at both 18 and 25°C, although germination percentage increased slightly at the higher temperature. Diffusates originating in other spore suspensions of the same isolate reduced germination percentage of spores taken at optimal concentration. The least effect occurred in diffusate taken from spores kept at their optimal concentration. Self-suppression of spore germination at unfavourable concentrations was diminished more or less by antioxidants (superoxide dismutase, catalase, mannitol or formate). The same compounds, added to spore diffusates, reduced their fungitoxicities. All diffusates generated superoxide radical (assayed by adrenalin oxidation sensitive to superoxide dismutase). This activity correlated positively with diffusate toxicity. Leaf inoculation of the susceptible cucumber cultivar at 18°C with spore suspensions at extreme densities, at which they germinated poorly in vitro, led to less disease severity then that at optimal density. In contrast, no disease symptoms appeared at 25°C. It is suggested that spores germinating at their extreme concentrations produced reactive oxygen species, suppressing the pathogen; this effect could reduce disease development at low temperatures. At high temperatures, however, this mechanism seems not to work, suggesting that plant infection may be reduced by other disease inhibiting factors.  相似文献   

Fluctuations of element concentrations during the growing season of Polytrichum formosum (Hedw.)     

Bernd Markert  Vera Weckert 《Water, air, and soil pollution》1989,43(1-2):177-189

Fourteen elements (Al, Ba, Ca, Cd, Cr, Cu, Fe, K, Mg, Ni, Pb, Sr, Ti, and Zn) were quantitatively determined by AES/ICP in aboveground parts of the endohydric moss Polytrichum formosum (Hedw.) after sampling over regular intervals from 1985 to 1987. With the exception of K, Mg, and Zn all elements showed a large continuous fluctuation (> 30%) during the growing season. Four different patterns of seasonal variation were found: (1) large seasonal variations of element concentrations (～80%) with maximum concentrations in winter and lowest concentrations in the summer months (Al, Fe, Cr, Mg, Pb, and Ti), (2) smaller seasonal variations (～50%) with maximum concentrations in winter and lowest concentrations in summer (Ba, Ca, Cd, Cu, Sr), (3) slight seasonal variations (～30%) with maximum concentrations in the summer (K), and (4) slight seasonal changes (～30%) with maximum concentrations in the winter (Mg and Zn). The relative biological variance of element concentrations between 9 different stands of Polytrichum formosum decreases in the following sequence: Ti, Al, Pb, Fe, Cr, Ni, Ba, Ca, Cu, Cd, K, Mg, Sr, Zn. The relative biological variance of individual elements is generally lower than the variance in element concentrations caused by seasonal changes. Because of its high biological variance for most elements investigated (seasonal as well as between different stands of Polytrichum formosum) this moss should only be used as a passive bioindicator, if all other environmental parameters are standardized.  相似文献   

Nutrient concentrations of peach‐tree leaves under deficit irrigation     

Isabel Abrisqueta  Rosario Quezada‐Martin  Juan P. Munguía‐López  M. Carmen Ruiz‐Sánchez  José M. Abrisqueta  Juan Vera 《植物养料与土壤学杂志》2011,174(6):871-873

The effect of different deficit‐irrigation treatments on the dynamics of mineral nutrients in leaves of peach trees growing under Mediterranean conditions was studied. Treatments consisted of a control, continuous deficit irrigation, regulated deficit irrigation, and partial root drying. The dynamics of nutrients were unchanged by the water deficits, though the amount absorbed was slightly modified. The advantages of deficit‐irrigation strategies with regard to water‐use efficiency were accompanied by the absence of any harmful effect on leaf mineral nutrition.  相似文献   

Determination of roasted pistachio (Pistacia vera L.) key odorants by headspace solid-phase microextraction and gas chromatography-olfactometry     

Aceña L  Vera L  Guasch J  Busto O  Mestres M 《Journal of agricultural and food chemistry》2011,59(6):2518-2523

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Acaricidal properties of extracts from the aerial parts of Hypericum polyanthemum on the cattle tick Boophilus microplus     

Ribeiro VL  Toigo E  Bordignon SA  Gonçalves K  von Poser G 《Veterinary parasitology》2007,147(1-2):199-203

Laboratory tests were carried out on larvae and adults of the cattle tick Boophilus microplus to determine the toxicity of n-hexane and crude methanolic extracts of Hypericum polyanthemum (Guttiferae) using the larval immersion test (LIT) and adult immersion test (AIT). In the AIT, the effectiveness of treatment against engorged females was assessed by measuring egg production: the n-hexane extract was found to have a small effect on the egg laying at the highest concentration (19.2% of egg-laying inhibition) whilst the crude methanolic extract did not affect the egg production. For the LIT the n-hexane extracts were highly toxic to the larvae at all the concentrations (100% of mortality). The crude methanolic extract was also toxic to the larvae at higher concentrations killing 100, 96.7, 84.7 and 52.7% at the concentrations of 50, 25, 12.5, and 6.25 mg/ml, respectively, 48 h after the immersion of the acarus.  相似文献   

Expression of select mRNA in Thoroughbreds with catastrophic racing injuries     

Allen E. Page  Emma Adam  Rick Arthur  Virginia Barker  Forrest Franklin  Ron Friedman  Timothy Grande  Michael Hardy  Bruce Howard  Emma Partridge  Matthew Rutledge  Mary Scollay  John C. Stewart  Alina Vale  David W. Horohov 《Equine veterinary journal》2022,54(1):63-73

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Unilateral jugular vein stenosis in five horses and experience with percutaneous transluminal angioplasty     

Ellen Paulussen  Annelies Decloedt  Lisse Vera  Laurence Lefere  Gunther van Loon 《Equine veterinary journal》2022,54(4):710-718

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