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201.
Observations obtained with a mobile pencil-beam Doppler radar revealed many previously unresolved structures within tornadic storms and tornadoes and helped verify various aspects of conceptual models. Radar data from the parent circulations indicate the existence of spiral reflectivity bands, intense radial wind shear zones, and multiple larger-scale velocity maxima. Tornado structures observed include debris shields, clear axial (eye) regions, multiple reflectivity bands surrounding the center of the eye, and occasional reflectivity protrusions into the eye. Velocity and reflectivity data from tornado-scale circulations show evidence of axial downdrafts. 相似文献
202.
Clarissa MR. Moreira Renato LS. Oliveira Gilberto A. Costa Katia B. Corgozinho Stelio PL. Luna Heloisa JM. Souza 《Veterinary anaesthesia and analgesia》2021,48(1):134-141
ObjectiveTo evaluate the analgesic efficacy and safety of tumescent local anesthesia (TLA) in cats undergoing unilateral mastectomy.Study designProspective clinical trial.AnimalsA total of 12 ovariohysterectomized female cats.MethodsAll animals were premedicated with pethidine (4 mg kg–1) intramuscularly (IM), followed by induction of anesthesia with propofol (5 mg kg–1) intravenously and maintenance with isoflurane in oxygen. A refrigerated TLA solution (15 mL kg–1, 8 °C) was injected using a Klein cannula. The solution was composed of 0.5 mL of epinephrine (1 mg mL–1) and 40 mL of 2% lidocaine added to 210 mL lactated Ringer’s solution (final lidocaine concentration 0.32%). Heart and respiratory rates, systolic arterial blood pressure, temperature and oxygen saturation were measured during anesthesia. Blood samples were collected from the jugular vein for measurement of plasma lidocaine concentration using high performance liquid chromatography. Postoperative pain scores were evaluated hourly for 6 hours. Analgesic rescue was performed with tramadol (2 mg kg–1) IM and meloxicam (0.15 mg kg–1) subcutaneously.ResultsPlasma lidocaine concentration peaked at 90 minutes after injection of TLA, but no concentration considered toxic for the species was measured. The median postoperative analgesia time was 6 hours after injection of TLA.ConclusionsThis study found that TLA prevented sympathetic response to noxious stimuli during anesthesia and provided satisfactory postoperative analgesia in cats submitted to total unilateral mastectomy, with no apparent signs of toxicity.Clinical relevanceTLA can prevent sympathetic stimulation resulting from noxious stimuli during anesthesia, promoting good intraoperative conditions, proving to be a viable addition to analgesia in cats submitted to a total unilateral mastectomy. 相似文献
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204.
Two switchable, mesoscopically periodic materials were created by combining crystalline colloidal array (CCA) self-assembly with the temperature-induced volume phase transition of poly(N-isopropylacrylamide) (PNIPAM). Body-centered-cubic CCAs of hydrated, swollen PNIPAM particles Bragg-diffract infrared, visible, and ultraviolet light weakly, whereas arrays of compact shrunken particles diffract efficiently. A tunable diffracting array was also created by embedding a CCA of polystyrene spheres within a PNIPAM hydrogel that swells and contracts with temperature; thus the array lattice constant varies with temperature, and the diffracted wavelength was thermally tunable across the entire visible spectrum. These materials may find applications in many areas of optics and materials science. 相似文献
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206.
JM Vazquez J Roca MA Gil C Cuello I Parrilla I Caballero JL Vazquez EA Martínez 《Reproduction in domestic animals》2008,43(S2):347-354
Low-dose AI procedures are required by the pig industry to efficiently utilize emerging sperm technologies, such as cryopreservation and sex-sorting. Currently, several different procedures for inseminating with a low or very low number of spermatozoa have been described. Deep intrauterine insemination allows the deposition of the spermatozoa in the depth of the uterine horn, allowing a significant reduction in the number of spermatozoa inseminated with maintenance of optimal reproductive performance. Intra-oviductal laparoscopic insemination has been recently applied in pigs. This technique has proved to be applicable with diluted and sex-sorted spermatozoa. This review discusses several problems encountered during the development of deep intrauterine insemination and intra-oviductal laparoscopic insemination of pigs and provides potential solutions for the practical application of both the technologies. 相似文献
207.
R Kasimanickam M Asay S Schroeder V Kasimanickam JM Gay JP Kastelic JB Hall WD Whittier 《Reproduction in domestic animals》2014,49(6):1063-1067
Profitability of a beef operation is determined by the proportion of cows attaining pregnancy early in the breeding season and those that are pregnant at the end of breeding season. Many factors, including temperament, contribute to those reproductive parameters. The objective of this study was to evaluate effects of temperament on reproductive performance of beef cows. In Experiment 1, Angus and Angus‐cross beef cows (n = 1546) from eight locations were assigned a body condition score (BCS; 1 = emaciated; 9 = obese) and chute exit and gait score (1 = slow exit, walk; calm temperament; 2 = jump, trot or run; excitable temperament). Cows were grouped with bulls (1 : 25 to 1 : 30; with satisfactory breeding potential and free of venereal disease) for an 85‐day breeding season. Pregnancy status and stage of gestation were determined (transrectal palpation) 35 days after the end of the breeding season. Controlling for BCS (p < 0.01) and handling facility (p < 0.0001) and handling facility by temperament score interaction (p < 0.001), breeding season pregnancy rate was lower in excited versus calm cows [88.6% (798/901) vs 94.1% (607/645); p < 0.001]. Cows with an excitable temperament took 24 more days to become pregnant compared to calm cows (median days to pregnancy, 35 vs 59 days; p < 0.0001). In Experiment 2, Angus and Angus‐cross beef cows (n = 1407) from 8 locations were assigned scores for body condition and chute exit and gait (as described in Experiment 1) and assigned to bulls (breeding sound and free of venereal disease; 1 : 25 to 1 : 30) for 85 days. Pregnancy status was determined by transrectal palpation at 2 and 6 months after the onset of the breeding season. Controlling for BCS (p < 0.05), pregnancy loss was higher in excited versus calm cows [5.5% (36/651) vs 3.2% (20/623), p < 0.0001]. In conclusion, beef cows with an excitable temperament had significantly lower reproductive performance than calmer cows. The modified two‐point chute exit–gait scoring method was repeatable and identified cattle with an excitable temperament. 相似文献
208.
Single layer centrifugation of fresh dromedary camel semen improves sperm quality and in vitro fertilization capacity compared with simple sperm washing 下载免费PDF全文
C Malo EG Crichton JM Morrell BS Pukazhenthi JA Skidmore 《Reproduction in domestic animals》2017,52(6):1097-1103
Single layer centrifugation (SLC) through a colloid is a tool for selecting viable mammalian spermatozoa but has not been used previously for fresh dromedary camel sperm. Semen from six camels (2 ejaculates/male) was diluted 1:5 (v:v) or 1:10 (v:v) in a Tris–citrate–fructose buffer for mechanical liquefaction by gentle pipetting. Following liquefaction, semen was processed either by SLC or by centrifugation without a colloid (control). Total and progressive motilities, CASA kinematics, vitality and acrosome integrity (eosin–nigrosin) and plasma membrane integrity (Hypo‐osmotic swelling test; HOST), and fertilizing ability in a heterologous assay (zona‐free goat oocytes) were evaluated. Both total (p = .003) and progressive motilities (p = .003) were higher in SLC‐processed than in control semen samples, irrespective of dilution. Positive HOST values increased when using colloid in 1:5 (p = .001) and 1:10 dilution (p = .010). Colloid‐selected sperm had higher penetration rates than controls (p < .001 and p = .02 for 1:5 and 1:10 dilutions, respectively). However, only the SLC sperm at 1:5 dilution showed higher percentages of pronuclear formation (p = .02) than controls. Dilution effect was only significant for total motility before in vitro fertilization, with higher values for the 1:5 dilution (p = .033). The recovery rates of motile sperm between dilutions were similar (26.1% vs 35.4%; p = .226). In conclusion, SLC is a promising tool for selecting functional dromedary camel sperm and warrants more research. 相似文献
209.
This case report describes the successful management of a stingray laceration and suspected envenomation using a combination of opioid analgesia, heat compression, antimicrobial therapy, surgical debridement and closure. Stingray envenomation in the dog is a rare clinical presentation and is yet to be documented in the Australian veterinary literature. Envenomation can be markedly painful and may cause swelling and local tissue necrosis. No consensus on treatment guidelines has been published. Diagnostics and treatments performed are outlined with recommendations on a management plan for future cases. 相似文献