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Availability and fragmentation of habitat are today identified as key determinants of population maintenance. Disentangling their relative effects is of crucial importance to adequately manage landscapes. However, the classical use of occurrence or abundance data as proxy to assess the responses of populations could be insufficient to detect less drastic impacts than short-term population extinction. We evaluated the effects of both habitat availability and fragmentation at three spatial scales on both the occurrence and two “physiological state” indicators (body condition and level of stress hormone) reflecting the physical state of common toads (Bufo bufo). Our study showed that occurrence was negatively affected only by habitat availability at the largest spatial scale whereas the both physiological state indicators studied at the population scale are significantly altered by both habitat availability and fragmentation at the finest spatial scale. Results obtained with occurrence and physiological state approaches substantially diverge, which highlights the need to also investigate proximal processes to deeply understand how populations are threatened by landscape modifications. The use of physiological state indicators, particularly of body condition, powerful and easy to obtain, could be particularly relevant to detect early warnings of population decline allowing a management before extinction. Only a complete investigation of the potential impacts of landscape on the different population processes could offer a realistic picture of the requirements of populations to avoid drastic alterations. 相似文献
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Bradley A Mullens William G Reifenrath Sarah M Butler 《Pest management science》2009,65(12):1360-1366
BACKGROUND: Straight‐chain, saturated fatty acids (particularly C8, C9 and C10) have some known behavioral effects on insects such as mosquitoes, and were tested in combination for potential repellency/antifeedant activity in bioassays against three significant muscoid flies of medical/veterinary importance: houseflies, horn flies and stable flies. RESULTS: Mixtures of C8, C9 and C10 (1:1:1; 15% total actives in formulation) were highly repellent to houseflies and horn flies at or below 1 mg formulation cm?2. Repellency time varied from < 1 day for houseflies to usually at least 3 days for horn flies. Individual longer‐chain‐length fatty acids were tested, and C11 repelled houseflies for up to 5–8 days, while C12 lasted 2 days. Minimum statistically significant repellency levels of the C8, C9 and C10 mixture (3 h after application) against horn flies were 0.06–0.12 mg cm?2. A liquid formulation of the 15% C8, C9 and C10 mixture in a silicone oil carrier (at 2.8 mg AI cm?2) was highly repellent against hungry stable flies in a blood‐feeding membrane bioassay for at least 8 h. CONCLUSION: The low toxicity and reasonable activity and persistence of these carboxylic acids make them good candidates for development as protective materials against pest flies in livestock settings. Copyright © 2009 Society of Chemical Industry 相似文献
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Colorimetry of wood specimens from French Guiana 总被引：1，自引：0，他引：1
Yoshihiko Nishino Gérard Janin Bernard Chanson Pierre Détienne Joseph Gril Bernard Thibaut 《Journal of Wood Science》1998,44(1):3-8
The color of 97 species of wood specimens from French Guiana was measured on their radial and tangential surfaces with a colorimeter. We obtained the tristimulus values of X, Y, and Z of the 10° standard observer under the illuminant of D
65, and the values of the CIELAB color system, L
*, a*, b*, C*, and h. When the lightness index (L
*) was <54, b
*, C
*, and h showed positive correlations against L
*. When L
* was >54, a
* and C
* showed negative correlations against L
*. These results imply that wood color should be discussed by separating wood specimens into the high and low-lightness groups. A good positive correlation was found between the L
* and h throughout the whole range of L
*. It is thought that the value of h can be an important index, as can L
*, for comparing of wood color because h shows a simple relation with L
*. 相似文献
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Journal of Pest Science - Organic anion-transporting polypeptides (OATPs) are integral membrane transporters that mediate cellular uptake of a broad range of substrates in humans. The functions of... 相似文献
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Hennig-Pauka I Baltes N Jacobsen I Stratmann-Selke J Gerlach GF Selbitz HJ Waldmann KH 《Berliner und Münchener tier?rztliche Wochenschrift》2008,121(5-6):189-197
For vaccine licensing data about efficiency and duration of protection are essential. Within the scope of the developement of a new subunit vaccine against Actinobacillus pleuropneumoniae (A.pp.) the protective efficiency over the whole length of the fattening period must be proven. This required infection experiments in finishing pigs. Eight pigs in the age of six months were infected experimentally into the trachea with an A.pp. serotyp 2 strain. To our knowledge data about the susceptibility of pigs of this age do not exist, so that the infectious dose for pigs of this age and this route of infection had to be determined. Two pigs each were infected with different doses of 10(10), 6 x 10(5), 8 x 10(3) and 2 x 10(3) CFU (colony forming units). The aim of the study was to produce a typical pleuropneumonia with fever and severe respiratory symptoms as well as characteristic pathomorphological lung alterations without loss of animals during the acute stage of infection. The pathogen should be cultivated from lung tissue. The recommended dose for testing the efficiency of vaccines turned out to be approximately 10(3) CFU A.pp. serotyp 2. 相似文献
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Torsten Meyer Janin Stratmann-Selke Jochen Meens Thomas Schirrmann Gerald F. Gerlach Ronald Frank Stefan Dübel Katrin Strutzberg-Minder Michael Hust 《Veterinary microbiology》2011,147(1-2):162-169
Pork meat is one of the major sources for human infections with Salmonella enterica subspecies enterica serovars. Further, zoonoses caused by S. enterica subspecies enterica serovars are responsible for substantial economical losses in industrial countries. Quick and reliable detection of this infection is urgently needed to improve consumer security. Due to its capability to identify infections independent of the species, a competitive ELISA is the preferable method for the detection of anti-Salmonella antibodies in serum. Recombinant antibody fragments (scFvs) were isolated from the naive human antibody gene library HAL7 by phage display. Recombinant produced outer membrane protein D (OmpD) of Salmonella Typhimurium was used as antigen. The characterization of the isolated single chain Fv (scFv) antibodies was done by enzyme-linked immunosorbent assay (ELISA), immunoblot, sequencing, epitope mapping and size exclusion chromatography (SEC). The detection of anti-OmpD IgGs in swine sera by competitive ELISA was shown in a proof of principle concept. Furthermore, the developed competitive ELISA would be compatible to a recently published DIVA vaccine, allow to distinguish between infected and vaccinated pigs. 相似文献
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The terminal branches of the recurrent laryngeal nerve (RLN) of three normal ponies and six horses with sub-clinical laryngeal disease were examined qualitatively and quantitatively in an attempt to explain the preferential denervation of the laryngeal adductor muscles in the neuropathy of idiopathic laryngeal hemiplegia (ILH). The myelinated fibre spectra of all the motor nerve fibres in the left and right abductor and adductor branches of the RLN in three normal ponies were measured. The density of myelinated fibres was also calculated. There was no significant difference between the larger group of myelinated fibres in the adductor or abductor branches. In the six horses with laryngeal hemiparesis, however, there was a marked preferential loss of the medium/large size myelinated fibres in the left adductor branch, although nerve fibre densities were not significantly different. While no simple morphometrical feature was found to explain the selective muscle denervation, the greater loss of large diameter myelinated fibres in the adductor branches confirms the earlier observation of adductor muscle susceptibility in the neuropathy of ILH. 相似文献
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Janin Reifenrath Daniel Gottschalk Nina Angrisani Silke Besdo Andrea Meyer-Lindenberg 《Acta veterinaria Scandinavica》2012,54(1):21
Background
Different animal models are used as fracture models in orthopaedic research prior to implant use in humans, although biomechanical forces can differ to a great extend between species due to variable anatomic conditions, particularly with regard to the gait. The rabbit is an often used fracture model, but biomechanical data are very rare. The objective of the present study was to measure axial forces, bending moments, and bending axis directly in the rabbit tibia in vivo. The following hypothesis was tested: Axial forces and bending moments in the mid-diaphysis of rabbit tibia differ from other experimental animals or indirectly calculated data.Methods
A minifixateur system with 4 force sensors was developed and attached to rabbit tibia (n = 4), which were subsequently ostectomised. Axial forces, bending moments and bending angles were calculated telemetrically during weight bearing in motion between 6 and 42 days post operation.Results
Highest single values were 201% body weight [% bw] for axial forces and 409% bw cm for bending moments. Whereas there was a continous decrease in axial forces over time after day 10 (P = 0.03 on day 15), a decrease in bending moments was inconsistent (P = 0.03 on day 27). High values for bending moments were frequently, but not consistently, associated with high values for axial forces.Conclusion
Axial forces in rabbit tibia exceeded axial forces in sheep, and differed from indirectly calculated data. The rabbit is an appropriate fracture model because axial loads and bending moments in rabbit tibia were more closely to human conditions than in sheep tibia as an animal model. 相似文献10.
Yoshihiko Nishino Gérard Janin Yuji Yainada Daisuke Kitano 《Journal of Wood Science》2000,46(4):267-272
Color measurements were made for sapwood specimens of 26 hardwood species. The densities of the specimens ranged from 258.5 to 945.6kg/m3. The colorimetric values and densities were compared among the species. The tristimulus values ofX, Y, andZ were poorly correlated with the densities. The chromaticity coordinatex had a good linear correlation with the densities of the wood specimens, especially in the transverse planes. The transverse plane of wood fibers is thought to emphasize the relative values in the long wavelength region of the visible ray.Part of this report was presented at the 49th annual meeting of the Japan Wood Research Society, Tokyo, April 1999 相似文献
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