Improved line weighting reduces seabird bycatch without affecting fish catch in the Brazilian pelagic longline fishery   总被引：1，自引：0，他引：1  

Rodrigo C. Santos  Augusto Silva‐Costa  Rodrigo Sant'Ana  Dimas Gianuca  Oliver Yates  Caio Marques  Tatiana Neves 《水产资源保护:海洋与淡水生态系统》2019,29(3):442-449

Tracking mite trophic interactions by multiplex PCR     

María Antonia Gmez‐Martínez  Tatiana Pina  Ernestina Aguilar‐Fenollosa  Josep A Jaques  Mnica A Hurtado 《Pest management science》2020,76(2):597-608

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Myeloperoxidase concentration in bronchoalveolar lavage fluid from healthy horses and those with recurrent airway obstruction          下载免费PDF全文

Tatiana Art  Thierry Franck  Pierre Lekeux  Brieuc de Moffarts  Laurent Couëtil  Martine Becker  Serge Kohnen  Ginette Deby-Dupont    Didier Serteyn 《Canadian journal of veterinary research》2006,70(4):291-296

The aim of this work was to measure the myeloperoxidase (MPO) concentration in bronchoalveolar lavage (BAL) fluid collected from horses with recurrent airway obstruction (RAO), both in crisis and in remission, as well as from healthy horses. Seven horses with RAO were exposed to moldy hay until the maximum change in pleural pressure was greater than 1.5 kPa. At that point, BAL was performed, and the total cell counts and percentages in the fluid were immediately determined. To measure the MPO concentration in BAL-fluid supernatant, we used a specific enzyme-linked immunosorbent assay with polyclonal antibodies against equine MPO. The tests were repeated on the horses with RAO after they had spent 2 mo on pasture. Six healthy horses serving as controls underwent the same tests. The absolute and relative neutrophil counts and the MPO concentration in the BAL fluid were significantly greater in the horses with an RAO crisis than in the control horses. After 2 mo on pasture, the horses that had been in RAO crisis were clinically normal, and their neutrophil counts and MPO levels in BAL fluid had significantly decreased; during remission their neutrophil counts were not significantly different from those in the healthy horses, but their MPO concentration remained significantly higher. This study showed that determining the MPO concentration in a horse's BAL fluid is technically possible and that during remission from RAO the concentration remains higher than normal. Thus, MPO may be a marker of neutrophil presence and activation in the lower airways.  相似文献   

Measurement of respiratory function by impulse oscillometry in horses     

van Erck E  Votion D  Art T  Lekeux P 《Equine veterinary journal》2004,36(1):21-28

REASONS FOR PERFORMING STUDY: Due to technical implementations and lack of sensitivity, pulmonary function tests are seldom used in clinical practice. Impulse oscillometry (IOS) could represent an alternative method. OBJECTIVES: To define feasibility, methodology and repeatability of IOS, a forced oscillation technique that measures respiratory resistance (Rrs) and reactance (Xrs) from 5 to 35 Hz during spontaneous breathing, in horses. METHODS: Using 38 healthy horses, Rrs and Xrs reference values were defined and influence of individual biometrical parameters was investigated. In addition, IOS measurements of 6 horses showing clinical signs of heaves were compared to those of 6 healthy horses. RESULTS: Airtightness and minimal dead space in the facemask were prerequisites to IOS testing and standardisation of head position was necessary to avoid variations in Rrs due to modified upper airway geometry. In both healthy and diseased animals, measurements were repeatable. In standard-type breeds, the influence of the horse's size on IOS parameters was negligible. An increase in R5Hz greater than 0.10 kPa/l/sec and R5Hz>R10Hz, combined with negative values of Xrs between 5 and 20 Hz, was indicative of heaves crisis. CONCLUSIONS: IOS is a quick, minimally invasive and informative method for pulmonary function testing in healthy and diseased horses. POTENTIAL RELEVANCE: IOS is a promising method for routine and/or field respiratory clinical testing in the equine species.  相似文献   

Direct determination of paclobutrazol residues in pear samples by liquid chromatography-electrospray tandem mass spectrometry     

Sancho JV  Pozo OJ  Zamora T  Grimalt S  Hernández F 《Journal of agricultural and food chemistry》2003,51(15):4202-4206

A rapid and sensitive liquid chromatography/electrospray ionization/tandem mass spectrometry (LC-ESI-MS-MS) method has been developed for the determination of the plant growth regulator paclobutrazol in pear samples. Extraction was performed with methanol by using a high-speed blender Ultra-Turrax, and 10 microL of pear extract was directly injected in the LC-ESI-MS-MS system without any previous sample treatment. The highest sensitivity of the method was achieved under MS-MS conditions obtaining a limit of detection of 0.7 microg/kg and a quantification limit of 5 microg/kg, with a run time of only 5.5 min. Recoveries for paclobutrazol from spiked pear samples at 0.005, 0.05, and 0.5 mg/kg were around 82-102% with relative standard deviations between 2 and 7%. The method was applied to real treated and untreated samples of pears, using quality control samples as a evaluation of the method reliability. Two MS-MS transitions were selected, one for quantification (294 > 70) and the other for confirmation of the analyte (296 > 70). All the experiments were performed in compliance with good laboratory practices.  相似文献   

Low genetic diversity threatens imminent extinction for the Hungarian meadow viper (Vipera ursinii rakosiensis)     

Beáta Újvári  Thomas Madsen  Tatiana KotenkoMats Olsson  Richard ShineHåkan Wittzell 《Biological conservation》2002,105(1):127-130

Meadow vipers (Vipera ursinii) are small venomous snakes whose range in Hungary has been greatly fragmented by anthropogenic habitat disturbance (especially, agriculture). We obtained DNA from a total of eight Hungarian snakes. Genetic variability at the major histocompatibility (Mhc) class I loci was much lower for these snakes than for specimens from two large Ukrainian populations. Within two Hungarian populations for which we had multiple individuals, band-sharing indices were 100 and 84.6% (versus 63.3 and 57% for the Ukraine populations). The Ukrainian snakes also displayed more RFLP fragments than the Hungarian vipers (mean 13.7 versus 9.0, respectively). In combination with reports of birth deformities, chromosomal abnormalities and low juvenile survival, these data strongly suggest that the Hungarian vipers are experiencing inbreeding depression. Genetic diversity is still present in the Hungarian vipers but among rather than within populations. Given the very low numbers of animals, the only feasible strategy to increase the genetic diversity and to save the Hungarian vipers from extinction is to implement a captive breeding program based on genetically screened animals.  相似文献   

Protected areas and frugivorous fish in tropical rivers: Small-scale fisheries,conservation and ecosystem services     

Paula Nagl  Gustavo Hallwass  Luís H. Tomazoni-Silva  Pedro P. Nitschke  Anais R. P. Rowedder  Astrid Tatiana Romero-Martinez  Renato A. M. Silvano 《水产资源保护:海洋与淡水生态系统》2021,31(10):2752-2771

1. Frugivorous fish provide often conflicting ecosystem services of seed dispersal and food provisioning in tropical rivers. Fishing may reduce the size and abundance of frugivorous fish, thus affecting their potential as seed dispersers, which could affect the conservation of these fish and of floodplain forests.
2. The goal of this study was to assess the influence of co-managed protected areas in the form of extractive reserves (RESEX) and small-scale fisheries on frugivorous fish in the Tapajós and Negro rivers, in the Brazilian Amazon. The study examined whether: (i) frugivorous fish are important for fisheries and selectively caught; and (ii) frugivorous fish abundance, size and fisheries catch per unit of effort are higher inside the RESEX than outside.
3. The analyses included fisheries-dependent data (3,753 fish landings) and independent data (12,730 sampled fish) collected in 16 fishing communities (eight for each river). In both rivers, frugivorous fish are among the 10 species caught the most and frugivorous biomass was proportionately higher in landings than in samplings, indicating fisheries selectivity towards these fishes.
4. In both rivers, catches of frugivorous fish were higher outside the RESEX than inside. Catch per unit effort and the proportion of frugivores in the catch were higher outside the RESEX in the Tapajós River but did not vary between sites inside and outside the RESEX in the Negro River. Frugivorous fish were larger inside the RESEX in the Negro, but smaller inside the RESEX in the Tapajós.
5. The results indicated that the ecosystem services of seed dispersal and food source provided by frugivorous fish are not in conflict in the tropical rivers studied. Therefore, these clearwater and blackwater rivers in the Brazilian Amazon show a balance between fisheries and conservation of frugivorous fish, which play an essential role in the functioning of tropical floodplain forest ecosystems.

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施肥对赣无系列油茶叶片SPAD值及养分的影响   总被引：3，自引：0，他引：3  

胡玉玲  胡冬南  周城师  汪峻  郭晓敏 《林业科技开发》2011,25(2)

以5年生赣无系列油茶为研究对象,采用随机区组试验设计,设置施鸡粪、复合肥、生物有机肥、油茶专用肥,不施肥对照(cK)5个处理,分别对春梢进行调查并采叶片样品进行分析,通过研究比较4种肥料对赣无油茶春季叶片叶绿度sPAD值、叶片养分及干物质积累量差异,并分析它们之间的关系,以期为赣无油茶品系丰产栽培、科学施肥及氮素丰缺指标测定优化提供依据.结果表明:(1)氮对油茶春季叶片sPAD值贡献率最高,钾对叶片干物质积累贡献率最高;(2)施油荼专用肥叶片叶绿度SPAD值和叶片干物质含量最高;(3)不施肥叶片养分含钾量最高,施有机肥叶片含磷最高,施复合肥叶片含氮磷钾都最低.  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   

A new approach for neutron moisture meter calibration: artificial neural network     

Ey��p Selim K?ksal  Bilal Cemek  Cengiz Art?k  Kadir Ersin Temizel  Mehmet Ta?an 《Irrigation Science》2011,29(5):369-377

The neutron moisture meter (NMM) is a widely used device for sensing soil water content (SWC). Calibration accuracy and precision of the NMM are critical to obtain reliable results, and linear regression analysis of SWC against NMM count data is the most common method of calibration. In this study, artificial neural network (ANN) calibration models were developed and compared with linear regression. For this purposes, training and validation data were obtained from 2 calibration and 16 testing plots, respectively. Calibration plots consist of wet and dry soil water conditions separately. Data measured in dry beans and red pepper plots that have four different water levels were used to determine validity of regression and ANN-based calibration models. Volumetric SWC and NMM count ratio measurements were taken for depth intervals of 30 cm throughout a 120-cm-deep soil profile. Several neural network architectures were explored in order to determine the optimal network architecture. Data analyses were conducted for each soil layer and for the whole profile, separately, based on both linear regression and ANN. Linear regression calibration equation coefficients of determination (r ²) for the 0–30, 30–60, 60–90 and 90–120 cm depth ranges calculated by regression models were 0.85, 0.84, 0.72 and 0.82, respectively, and r ² values were 0.94, 0.95, 0.87 and 0.88 based on ANN models, respectively. Using the data set from the entire 120-cm soil profile for calibration by ANN, the r ² value was raised to 0.97.  相似文献