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91.
Sophie E. Hale Barry A. Gardiner Axel Wellpott Bruce C. Nicoll Alexis Achim 《European Journal of Forest Research》2012,131(1):203-217
Wind damage to forests is an important ecological disturbance factor. At the same time, it can have serious economic consequences
due to a reduction in timber production. Current models for predicting the risk of wind damage are useful, but generally only
focus on the “mean” tree within uniform stands. This paper presents measurements made of wind loading on trees of different
sizes within four forest stands of different structure and management history, but all well-acclimated to current wind conditions.
Each tree demonstrated a linear relationship between the maximum hourly turning moment and the square of the average hourly
wind speed at the canopy top; we defined this ratio (the gradient of the line M
max vs. u
2) as the turning moment coefficient (T
C). T
C was correlated with tree size, in a relationship that differed little between the four forest sites despite the differences
between the stands. The relationship between T
C and individual tree competition within each stand was investigated, using both distance-independent and distance-dependent
competition indices. All sites showed decreasing T
C with increasing competition. However, the relationships differed between sites and would also be expected to change through
time for a single site. The distance-dependent indices offered no improvement over the simpler, non-spatial indices that required
only a diameter distribution. We suggest how, subject to further work, the results presented could be applied to calculate
the risk of wind damage to trees of different sizes within a forest stand, and how the risk of wind damage to individual trees
might change in response to thinning. 相似文献
92.
Outbreaks of renal failure associated with melamine and cyanuric acid in dogs and cats in 2004 and 2007. 总被引:25,自引:0,他引:25
Cathy A Brown Kyu-Shik Jeong Robert H Poppenga Birgit Puschner Doris M Miller Angela E Ellis Kyung-Il Kang Steffen Sum Alexis M Cistola Scott A Brown 《Journal of veterinary diagnostic investigation》2007,19(5):525-531
Sixteen animals affected in 2 outbreaks of pet food-associated renal failure (2 dogs in 2004; 10 cats and 4 dogs in 2007) were evaluated for histopathologic, toxicologic, and clinicopathologic changes. All 16 animals had clinical and laboratory evidence of uremia, including anorexia, vomiting, lethargy, polyuria, azotemia, and hyperphosphatemia. Where measured, serum hepatic enzyme concentrations were normal in animals from both outbreaks. All animals died or were euthanized because of severe uremia. Distal tubular lesions were present in all 16 animals, and unique polarizable crystals with striations were present in distal tubules or collecting ducts in all animals. The proximal tubules were largely unaffected. Crystals and histologic appearance were identical in both outbreaks. A chronic pattern of histologic change, characterized by interstitial fibrosis and inflammation, was observed in some affected animals. Melamine and cyanuric acid were present in renal tissue from both outbreaks. These results indicate that the pet food-associated renal failure outbreaks in 2004 and 2007 share identical clinical, histologic, and toxicologic findings, providing compelling evidence that they share the same causation. 相似文献
93.
Florence Ollivet-Courtois Alexis Lécu Rebecca A Yates Lucy H Spelman 《Journal of zoo and wildlife medicine》2003,34(3):292-295
Regional digital i.v. perfusion was used to treat a severe sole abscess associated with a wire foreign body in a 19-yr-old female Asian elephant (Elephas maximus) housed at the Paris Zoo. The cow presented with acute right forelimb lameness and swelling that persisted despite 4 days of anti-inflammatory therapy. Under anesthesia, a 10- x 0.5- x 0.5-cm wire was extracted from the sole of the right foot. There was a 2-cm-deep, 7-cm-diameter abscess pocket that was subsequently debrided. Regional digital i.v. perfusion was performed and repeated 15 days later, using cefoxitin and gentamicin on both occasions. Between treatments, the cow received trimethoprim-sulfamethoxazole and phenylbutazone orally. Within 2 days of administering anesthesia and the first perfusion treatment, the lameness improved dramatically. When phenylbutazone was discontinued 1 wk after the first treatment, the lameness had completely resolved. At the second treatment, there was no evidence of further soft tissue infection, and the abscess pocket had resolved. 相似文献
94.
This case report describes for the first time sarcoids in tapirs (Tapirus bairdii), namely, a 2-year-old male and a 3.6-year-old female born and housed at the same facility. The male presented with a 3-cm nodular, red, pedunculated, hairless, ulcerated mass on the inner surface of the left pinna. No recurrence or additional growths were present during the 3 years following surgical excision of the mass. The female presented with a similar 2-cm mass on the inner surface of the right pinna, which recurred 2 months following surgical excision, but was subsequently successfully treated locally with liquid nitrogen with no further recurrence during a 2-year follow-up period. Histologically, these two masses closely resembled equine sarcoids. Similarly, an association with bovine papillomavirus 1 was demonstrated using polymerase chain reaction and in situ hybridization. 相似文献
95.
96.
Berrocal A López A 《The Canadian veterinary journal. La revue veterinaire canadienne》2007,48(3):305-306
A mass was removed from the nostril of a mule that exhibited unilateral epistaxis and nasal discharge. Impression smears revealed oval structures consistent with spores of Rhinosporidium seeberi. Microscopically, the mass was composed of fibrovascular granulomatous tissue containing sporangia R. seeberi. Surgical excision and antifungal treatment proved curative. 相似文献
97.
C. Marie-Magdeleine M. Mahieu S. D’Alexis L. Philibert H. Archimede 《Research in veterinary science》2010,89(1):88-92
Tabernaemontana citrifolia (Apocynaceae) is traditionally used as an anthelmintic preparation for ruminants in Guadeloupe (French West Indies). This study was carried out to evaluate the in vitro effect of this plant against the parasitic nematode of small ruminants Haemonchus contortus. Three extracts (aqueous, methanolic and dichloromethane) of T. citrifolia fruit, leaf and root were tested on four developmental stages of the parasite, using egg hatch assay (EHA), larval development assay (LDA), L3 migration inhibition assay (LMI), and adult worm motility assay (AWM). Compared to the negative control, significant effects were observed for the different parts of T. citrifolia but with differences depending on the parasitic stage; efficacies on the larval development of H. contortus from 88.9% to 99.8% for fruit, from 72.1% to 83.8% for root and from 33.5% to 85% for leaf with dose-dependent effect for the methanolic extract. The root gave the best result on EHA (22.7% efficacy for dichloromethane extract) and AWM (56% efficacy, with dose-dependent effect for dichloromethane extract) and the leaf on LMI (49.4% efficacy). These results suggest that T. citrifolia possess anthelmintic activity against H. contortus. The active ingredients responsible for the activity could be the alkaloid compounds present in the plant parts of the plant. 相似文献
98.
Irina Gladkikh Margarita Monastyrnaya Elena Zelepuga Oksana Sintsova Valentin Tabakmakher Oksana Gnedenko Alexis Ivanov Kuo-Feng Hua Emma Kozlovskaya 《Marine drugs》2015,13(10):6038-6063
Sea anemones are a rich source of Kunitz-type polypeptides that possess not only protease inhibitor activity, but also Kv channels toxicity, analgesic, antihistamine, and anti-inflammatory activities. Two Kunitz-type inhibitors belonging to a new Heteractis crispa RG (HCRG) polypeptide subfamily have been isolated from the sea anemone Heteractis crispa. The amino acid sequences of HCRG1 and HCRG2 identified using the Edman degradation method share up to 95% of their identity with the representatives of the HCGS polypeptide multigene subfamily derived from H. crispa cDNA. Polypeptides are characterized by positively charged Arg at the N-terminus as well as P1 Lys residue at their canonical binding loop, identical to those of bovine pancreatic trypsin inhibitor (BPTI). These polypeptides are shown by our current evidence to be more potent inhibitors of trypsin than the known representatives of the HCGS subfamily with P1Thr. The kinetic and thermodynamic characteristics of the intermolecular interactions between inhibitors and serine proteases were determined by the surface plasmon resonance (SPR) method. Residues functionally important for polypeptide binding to trypsin were revealed using molecular modeling methods. Furthermore, HCRG1 and HCRG2 possess anti-inflammatory activity, reducing tumor necrosis factor-α (TNF-α) and interleukin 6 (IL-6) secretions, as well as proIL-1β expression in lipopolysaccharide (LPS)-activated macrophages. However, there was no effect on nitric oxide (NO) generation. 相似文献
99.
Billard A Fillinger S Leroux P Lachaise H Beffa R Debieu D 《Pest management science》2012,68(5):684-691
BACKGROUND: Fenhexamid, a sterol biosynthesis inhibitor effective against Botrytis, inhibits the 3‐ketoreductase (Erg27) involved in C‐4 demethylation. Several fenhexamid‐resistant phenotypes have been detected in Botrytis cinerea populations from French vineyards. The field isolates with the highest resistance levels display amino acid changes in Erg27 (F412S, F412I or F412V). RESULTS: Fenhexamid‐resistant mutants were generated by site‐directed mutagenesis of the erg27 gene in a sensitive recipient strain to overcome the impact of different genetic backgrounds. The wild‐type erg27 allele was replaced by the three mutated alleles (erg27F412S/I/V) by homologous recombination. These isogenic strains were shown to be fenhexamid‐resistant and were used to quantify the impact of F412 mutations on fungal fitness. Several parameters, including radial growth, the production of sclerotia and conidia, freezing resistance and aggressiveness, were quantified in laboratory conditions. Analysis of variance demonstrated significant differences between the mutant and parental strains for some characters. In particular, the mutants grew more slowly than the wild‐type strain and displayed variations in the production of sclerotia and conidia with temperature and susceptibility to freezing. CONCLUSIONS: The results highlight a moderate but significant impact of F412 mutations on the survival capacity of B. cinerea strains displaying high levels of resistance to fenhexamid in laboratory conditions, potentially limiting their dispersal and persistence, particularly in terms of overwintering, in field conditions. Copyright © 2011 Society of Chemical Industry 相似文献
100.
Floudas D Binder M Riley R Barry K Blanchette RA Henrissat B Martínez AT Otillar R Spatafora JW Yadav JS Aerts A Benoit I Boyd A Carlson A Copeland A Coutinho PM de Vries RP Ferreira P Findley K Foster B Gaskell J Glotzer D Górecki P Heitman J Hesse C Hori C Igarashi K Jurgens JA Kallen N Kersten P Kohler A Kües U Kumar TK Kuo A LaButti K Larrondo LF Lindquist E Ling A Lombard V Lucas S Lundell T Martin R McLaughlin DJ Morgenstern I Morin E Murat C Nagy LG Nolan M Ohm RA Patyshakuliyeva A 《Science (New York, N.Y.)》2012,336(6089):1715-1719
Wood is a major pool of organic carbon that is highly resistant to decay, owing largely to the presence of lignin. The only organisms capable of substantial lignin decay are white rot fungi in the Agaricomycetes, which also contains non-lignin-degrading brown rot and ectomycorrhizal species. Comparative analyses of 31 fungal genomes (12 generated for this study) suggest that lignin-degrading peroxidases expanded in the lineage leading to the ancestor of the Agaricomycetes, which is reconstructed as a white rot species, and then contracted in parallel lineages leading to brown rot and mycorrhizal species. Molecular clock analyses suggest that the origin of lignin degradation might have coincided with the sharp decrease in the rate of organic carbon burial around the end of the Carboniferous period. 相似文献