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51.
P. Betsch D. Bonal N. Breda P. Montpied M. Peiffer A. TuzetA. Granier 《Agricultural and Forest Meteorology》2011,151(5):531-543
The exceptional soil drought and heat wave that occurred in Europe in summer 2003 provided a good opportunity to analyze the response of forest ecosystems to extreme climatic conditions. This work aimed at studying the functioning of exchangeable water reservoirs of beech trees under climatic and edaphic constraints, in a 37-year-old beech stand located in north-eastern France. We characterised the impact of drought on seasonal variations in water fluxes at the tree (sap flow measurements) and the forest (eddy covariance measurements) scales and estimated (i) the daily water storage capacity of beech trees as the difference between stand-scaled sap flow and water vapour flux over the stand and (ii) the contribution of exchangeable water in tree reservoirs to the total tree transpiration, under non-limiting soil water (summer 2002) or severe soil drought conditions (summer 2003). In parallel, daily variations in trunk circumference were analyzed to estimate the contribution of elastic tissues as a compartment for water storage to tree transpiration.Stand transpiration was strongly reduced by soil water shortage (up to 80% at the peak of drought in August 2003). From the beginning of August 2003, we observed daytime contraction of stem circumference, with only partial, or even no night recovery, suggesting that trees were less and less able to refill the elastic and strongly depleted reservoirs. Even if those elastic reservoirs were active throughout the season, the corresponding volume of water withdrawn for tree transpiration remained very low (maximum 1% of the daily transpiration). Thus, elastic tissue reservoirs play a minor role in the total water budget of beech trees.The amount of water depleted daily from the whole reservoirs was much higher than the water extracted from elastic tissues. Furthermore, the contribution of total exchangeable water within trees to the transpiration stream increased during the dry period (from a few percent to 67% at the peak of the drought) and was positively correlated with soil water shortage. Our results thus clearly demonstrated the strong sensitivity of beech to both climate and drought and the major role of whole tree water reservoirs to maintain leaf transpiration under severe drought. 相似文献
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53.
Julia Deutsch Colette Jolliffe Emma Archer Elizabeth A. Leece 《Veterinary anaesthesia and analgesia》2017,44(4):794-802
Objective
To assess quality of sedation following intramuscular (IM) injection of two doses of alfaxalone in combination with butorphanol in cats.Study design
Prospective, randomized, ‘blinded’ clinical study.Animals
A total of 38 cats undergoing diagnostic imaging or noninvasive procedures.Methods
Cats were allocated randomly to be administered butorphanol 0.2 mg kg?1 combined with alfaxalone 2 mg kg?1 (group AB2) or 5 mg kg?1 (group AB5) IM. If sedation was inadequate, alfaxalone 2 mg kg?1 IM was administered and cats were excluded from further analysis. Temperament [1 (friendly) to 5 (aggressive)], response to injection, sedation score at 2, 6, 8, 15, 20, 30, 40, 50 and 60 minutes, overall sedation quality scored after data collection [1 (excellent) to 4 (inadequate)] and recovery quality were assessed. Heart rate (HR), respiratory rate (fR) and arterial haemoglobin saturation (SpO2) were recorded every 5 minutes. Groups were compared using t tests and Mann–Whitney U tests. Sedation was analysed using two-way anova, and additional alfaxalone using Fisher's exact test (p < 0.05).Results
Groups were similar for sex, age, body mass and response to injection. Temperament score was lower in group AB2 [2 (1–3)] compared to AB5 [3 (1–5)] (p = 0.006). Group AB5 had better sedation at 6, 8, 20 and 30 minutes and overall sedation quality was better in AB5 [1 (1–3)], compared to AB2 [3 (1–4)] (p = 0.0001). Additional alfaxalone was required for 11 cats in AB2 and two in AB5 (p = 0.005). Recovery quality, HR, fR and SpO2 were similar. Seven cats required oxygen supplementation. Complete recovery times were shorter in AB2 (81.8 ± 24.3 versus 126.6 ± 33.3 minutes; p = 0.009). Twitching was the most common adverse event.Conclusions and clinical relevance
In combination with butorphanol, IM alfaxalone at 5 mg kg?1 provided better quality sedation than 2 mg kg?1. Monitoring of SpO2 is recommended. 相似文献54.
OBJECTIVE: To describe an assisted anesthetic recovery technique using a tilt table for horses after high-risk orthopedic-related procedures and to evaluate outcome. STUDY DESIGN: Retrospective study. SAMPLE POPULATION: Anesthetic recoveries (n=54) for 36 horses. METHODS: Medical records (April 1994-October 2005) for horses that had high-risk orthopedic surgery and recovery from general anesthesia on a tilt table were reviewed. Information about the surgical procedure, anesthetic and recovery period was analyzed. RESULTS: Of 54 anesthetic recoveries, 1 horse (1.9%) had complete failure of internal fixation during recovery and was euthanatized. Six (11% recoveries) horses failed to adapt to the tilt table system, which necessitated transfer to a conventional recovery room. Complications without important consequences for clinical outcome (skin abrasions, myositis, cast breakage, partial implant failure) occurred during 8 (15%) recoveries. CONCLUSIONS: A tilt table recovery system was associated with minimal incidence of serious complications. Potential disadvantages of the system are the number of personnel required, longer recovery time, and the need for a specialized table. CLINICAL RELEVANCE: A tilt table is a useful system for recovering horses believed to be at increased risk of injury during anesthetic recovery after high-risk orthopedic-related procedures. 相似文献
55.
Lynn Kay Carta Zafar A. Handoo Shiguang Li Mihail Kantor Gary Bauchan David McCann Colette K. Gabriel Qing Yu Sharon Reed Jennifer Koch Danielle Martin David J. Burke 《Forest Pathology》2020,50(2)
Symptoms of beech leaf disease (BLD), first reported in Ohio in 2012, include interveinal greening, thickening and often chlorosis in leaves, canopy thinning and mortality. Nematodes from diseased leaves of American beech (Fagus grandifolia) sent by the Ohio Department of Agriculture to the USDA, Beltsville, MD in autumn 2017 were identified as the first recorded North American population of Litylenchus crenatae (Nematology, 21, 2019, 5), originally described from Japan. This and other populations from Ohio, Pennsylvania and the neighbouring province of Ontario, Canada showed some differences in morphometric averages among females compared to the Japanese population. Ribosomal DNA marker sequences were nearly identical to the population from Japan. A sequence for the COI marker was also generated, although it was not available from the Japanese population. The nematode was not encountered in Fagus crenata (its host in Japan) living among nematode‐infested Fagus grandifolia in the Holden Arboretum, nor has L. crenatae been reported in American beech in Japan. The morphological and host range differences in North American populations are nomenclaturally distinguished as L. crenatae mccannii ssp. n. from the population in Japan. Low‐temperature scanning electron microscopy (LT‐SEM) demonstrated five lip annules and a highly flexible cuticle. Females, juveniles and eggs were imaged within buds with a Hirox Digital microscope and an LT‐SEM. Nematodes swarmed to the tips of freshly cut beech buds, but explants could not be maintained. Inoculation of fresh nematodes from infested leaves or buds to buds or leaves of F. grandifolia seedlings resulted in BLD leaf symptoms. Injuring dormant buds prior to nematode application, in fall or spring, promoted the most reliable symptom expression. The biogeography and physiology of anguinid nematode leaf galling, and potential co‐factors and transmission are discussed. 相似文献
56.
Helio Garcia Leite Mayra Luiza Marques da Silva Daniel Henrique Breda Binoti Leonardo Fardin Fausto Hissashi Takizawa 《European Journal of Forest Research》2011,130(2):263-269
The objective of this study was to obtain neural networks that would precisely estimate inside-bark diameter (d ib ) and heartwood diameter (d h ) and compare to the results obtained by the Taper models. The databank was formed so as to eliminate inconsistent and biased data, and stratified: minimum d ib of 4, 6 and 8 cm and minimum d h of 10, 15 and 20 cm. The adjusted Taper model used was the Kozak model. For the fitting of artificial neural networks (ANN), tests were performed to identify the independent variables and the database scope level, i.e., the following input variables were tested: diameter at breast height (dbh), total height (H), height at diameter d ib or d h (h) and outside-bark diameter at h (d ob ), bark thickness at 1.3 m and project, and the scope at database level or project level. The estimates obtained by the neural networks and Kozak model were evaluated by residual graphs in function of the respective diameter observed and graph of the observed versus estimated values. ANN were found to be more efficient in estimating inside-bark and heartwood diameters for Tectona grandis trees than the Kozak model. The variables that must be used to fit the networks are dbh, H, h and d ob . Stratification by project results in precision gain, with precision being higher for wider commercial diameters. Thus, linear-type artificial neural networks can be efficient in describing the taper of Tectona grandis trees. 相似文献
57.
58.
Mark A. Brady Jeffrey S. Dennis Colette Wagner‐Mann 《Journal of Veterinary Emergency and Critical Care》2003,13(1):1-6
Objective: To determine whether plasma from a heparinized hematocrit tube placed on a urine dipstick would accurately reflect (positive or negative) urine ketone results in diabetic dogs and cats. Design: Prospective study, 37 dogs and 43 cats, with a known history of diabetes or hyperglycemia, glucosuria, and symptoms of undiagnosed diabetes mellitus were tested. Setting: Veterinary Referral Hospital. Animals: Client owned dogs and cats. Interventions: None. Measurement and main results: Heparinized plasma and urine ketone results were recorded using urine reagent strips. Plasma dipstick results were compared to urine dipstick results as the standard. Results were recorded based on the color chart provided by the manufacturer. Two individuals were responsible for verifying the results of the colorimetric test. Test efficiency was 97% (sensitivity = 96%, specificity = 100%) for the canine population, 93% (sensitivity = 100%, specificity = 83%) for the feline population, and 95% (sensitivity = 98%, specificity = 91%) for the total population. Four of 80 animals were found to have discordant results (1 dog and 3 cats). Conclusion: Plasma from heparinized hematocrit tubes is clinically useful for detecting the presence or absence of ketonuria, and therefore ketosis, in diabetic dogs and cats using urine dipstick colorimetric methodology. 相似文献
59.
Terrell A. Holliday DVM PhD Holly J. Nelson DVM D. Colette Williams BS Neil Willits PhD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1992,6(3):166-174
In a survey of 900 Dalmatian dogs, brainstem auditory-evoked responses (BAER) and clinical observations were used to determine the incidence and sex distribution of bilateral and unilateral BAER abnormalities and their association with heterochromia iridis (HI). To assess the efficacy of BAER testing in guiding breeding programs, data from 749 dogs (subgroup A), considered to be a sample of the population at large, were compared with data from a subgroup (subgroup B; n = 151) in which selection of breeding stock had been based on BAER testing from the beginning of the 4-year survey. Brainstem auditory-evoked responses were elicited by applying click stimuli unilaterally, while applying a white noise masking sound to the contralateral ear. Under these conditions, BAER were either normal, unilaterally absent, or bilaterally absent. Dogs with bilaterally absent BAER were clinically deaf; dogs with unilaterally absent BAER were not clinically deaf but appeared dependent on their BAER-normal ears for their auditory-cued behavior. Dogs with unilaterally absent BAER often were misidentified as normal by uninformed observers. Among the 900 dogs, 648 (72.0%) were normal, 189 (21.0%) had unilateral absence of BAER, and 63 (7.0%) had bilateral absence of BAER or were clinically deaf and assumed to have bilaterally absent BAER (n = 4). Total incidence in the population sampled was assumed to be higher, because some bilaterally affected dogs that would have been members of subgroup A undoubtedly did not come to our attention. Among females, 24.0% were unilaterally abnormal and 8.2% were bilaterally abnormal whereas, among males, 17.8% were unilaterally abnormal and 5.7% were bilaterally abnormal.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
60.
Michael D. Matthewson Graham Hughes Ian S. Macpherson Colette P. Bernard 《Pest management science》1981,12(4):455-462
Screening techniques are described for the evaluation of the activity of tick repellents in vitro and in vivo, for the control of ticks of veterinary importance. In addition a modification of the in-vitro technique is described whereby the knockdown activity of chemicals may be assessed. There was a lack of correlation between results obtained in vitro and those obtained in vivo. Butopyranoxyl and N, N-diethyl-m-toluamide, which were highly active in vitro, showed only medium to low activity in vivo. Conversely, benzyl benzoate and dimethyl carbate, which were highly active in vivo, showed only low activity in vitro. Chemical breakdown, volatility, the ability of the chemical to bind to hair and skin, and differences in the behaviour and the morphology and physiology of the sense organs between larval and adult Rhipicephalus evertsi evertsi (Neumann 1897) are suggested as likely explanations for these differences in activity. Of the four synthetic pyrethroids tested, cypermethrin, deltamethrin, permethrin and fenvalerate, only the first three were shown to have good knockdown activity but only two, deltamethrin and permethrin, produced significant mortality of the exposed larvae. Further tests would be required to determine whether there is a correlation between knockdown and mortality. 相似文献