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21.
Hay AE 《Science (New York, N.Y.)》1984,225(4667):1154-1156
Acoustic backscatter observations at 200 kilohertz were made of the buoyant plume from a submarine spring at a depth of 47 meters in Cambridge Fiord, Baffin Island. Vertical velocities of up to 37 centimeters per second are inferred from the ascent rates of discrete scattering structures in the plume. 相似文献
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23.
Seasonal changes in respiration rates of copepodite stage V Calanus finmarchicus (Gunnerus) 总被引:1,自引:0,他引:1
Copepodite stage V Calanus finmarchicus were collected at locations on the continental shelf north of Scotland, in the Faroe–Shetland Channel and west of Ireland on six occasions covering winter, spring and summer from October 1993 to June 1995. Oxygen consumption by the overwintering and active spring/summer population of animals was determined at temperatures close to in situ temperatures. Laboratory measurements of oxygen consumption were also made at standardized temperatures (0°C, 5°C, 7°C and 12.5°C) to determine the sensitivity of animals to temperature change in the different seasons. Rates of oxygen consumption were very low (7–30 μmol O2 gC−1 h−1 ) at in situ temperatures during the winter and early spring and significantly higher (105–219 μmol O2 gC−1 h−1 ) for the active surface population in May and June. Animals collected from the overwintering population showed no significant response to changes in temperature. Due to the low respiration rates, the calculated rate of decrease in carbon content in diapausing copepodite stage CV was very low (approximately 0.250 μgC day−1 ). The respiration rates were used to construct a model to estimate survival of the animals with an initial carbon content equivalent to that expected of animals in October. The results showed that in order to survive during winter and have enough energy for moulting and migration to the surface in the spring, these animals have to live at temperatures close to 0°C and be in a diapause state. 相似文献
24.
In the Upper Zambezi and Okavango ecoregions, Brycinus lateralis, Hepsetus cuvieri, Schilbe intermedius and Serranochromis macrocephalus are important in subsistence fisheries, while S. intermedius and S. macrocephalus are often caught in commercial catches. Despite their importance, there is little information on their age and growth and age validation. Growth zone deposition rate in otoliths of B. lateralis, H. cuvieri, S. intermedius and S. macrocephalus was validated as annual using edge analysis in this study. Annual deposition of growth zones was corroborated by a fluorochrome marking experiment. Both methods demonstrated that one growth zone was deposited annually. Edge analysis demonstrated that the highest proportion of opaque zones was detected between August and December, most likely as a result of slow growth during lower temperature water during the preceding winter. With growth zone deposition validated as annual, future research should focus on determining the growth, maturity and mortality rates of these species, parameters which are important for their management. 相似文献
25.
A six-month-old male golden retriever was presented with a shortened radius and ulna and valgus deformity of the carpus secondary to premature closure of the distal radial and ulnar physes. Osteotomies of the radius and ulna were performed and the antebrachium was lengthened over eight weeks using a Wagner apparatus. This external fixation distractor is used in humans for limb-lengthening procedures. In this case, it was used to correct the angular deformity and to lengthen the limb. 相似文献
26.
K. L. Hepworth‐Warren B. L. Hay Kraus D. M. Wong A. C. Krull G. L. Metcalf 《Equine Veterinary Education》2017,29(11):603-608
This report describes an 11‐year‐old Percheron mare that presented with signs of colic and was ultimately diagnosed with bacterial peritonitis of unknown origin. Bacterial culture of a peritoneal fluid sample isolated 2 Clostridial species, one of which was strongly suspected to be Clostridium haemolyticum. The horse was markedly hypoalbuminaemic at presentation, leading to the development of low oncotic pressure and ventral oedema. The mare was administered a low molecular weight/low molar substitution hydroxyethyl starch solution in conjunction with other therapies that resulted in marked improvement of clinical signs. The purpose of this report is to describe the clinical findings associated with equine peritonitis associated with C. haemolyticum, a rarely identified pathogen in the horse. Secondly, this report serves to describe the beneficial effects of tetrastarch administration in a clinical case with severe hypoalbuminaemia and ventral oedema. 相似文献
27.
Niel A. Karrow Qiumei You Carl McNicoll Jack Hay 《Canadian journal of veterinary research》2010,74(1):30-33
Sheep were subjected to immune challenge with either recombinant human interleukin-6 (rhIL-6; 2.0 μg/kg; n = 5), Escherichia coli lipopolysaccharide (LPS) endotoxin (400 ng/kg; n = 7), or saline (n = 6) to determine if IL-6 activates the febrile and hypothalamic-pituitary-adrenal axis (HPAA) responses in sheep, and to compare these responses with those associated with endotoxemia. Blood was collected over time to measure plasma adrenocorticotropic hormone (ACTH) and serum cortisol concentrations as indicators of HPAA activity. Unlike LPS, rhIL-6 was not pyrogenic in sheep at this challenge dose. In contrast, rhIL-6 elicited ACTH and cortisol responses that peaked earlier than those induced by LPS. These results suggest that this dose of IL-6, alone, is not sufficient to elicit the febrile response in sheep, however, it is a potent activator of the ovine HPAA response. 相似文献
28.
M. Barimani S. J. Pethybridge N. Vaghefi F. S. Hay P. W. J. Taylor 《Plant pathology》2013,62(6):1248-1257
A new pathogen of pyrethrum (Tanacetum cinerariifolium) causing anthracnose was described as Colletotrichum tanaceti based on morphological characteristics and a four‐gene phylogeny consisting of rDNA‐ITS, β‐tubulin (TUB2), glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH) and actin (ACT) gene sequences. The fungus produced perithecia in culture, requiring an opposite mating type isolate in a heterothallic manner. The initial infection strategy on pyrethrum leaves involved the formation of appressoria followed by production of multilobed infection vesicles in the epidermal cells. Infection and colonization then proceeded through thinner secondary hyphae, which resulted in the initial production of water‐soaked lesions followed by black necrotic lesions. The infection process was suggestive of a hemibiotrophic infection strategy. Moreover, phylogenetic analysis clearly showed that C. destructivum, C. higginsianum and C. panacicola were separate species that also had similar intracellular hemibiotrophic infection strategies as C. tanaceti, which all clustered in the C. destructivum complex. Colletotrichum spp. were detected at 1% incidence in seed of 1 of 19 seed lines, indicating the potential for seed as a source of inoculum into crops. Colletotrichum tanaceti was detected in leaf lesions from 11 of 24 pyrethrum fields surveyed between April and July 2012, at a frequency of 1·3–25·0% of lesions. Anthracnose probably contributes to the complex of foliar diseases reducing green leaf area in pyrethrum fields in Australia. 相似文献
29.
K. P. Svoboda R. K. M. Hay P. G. Waterman 《The Journal of Horticultural Science and Biotechnology》2013,88(6):659-665
Stands of the annual culinary herb summer savory (Satureja hortensis L) were grown over four contrasting seasons, 1984-87, at Auchincruive in southwest Scotland. All crops matured in mid- to late August, yielding volatile oils of high quality. Total dry-matter yields per hectare were similar to those reported from eastern Europe, but oil yields were lower because of the genotype used, and there was considerable variation in dry-matter and oil yields between seasons. Variation in crop management (planting date, fertilization) affected oil yield only through changes in crop dry-matter production. Methods of increasing dry-matter and oil yields, and the potential of summer savory as an alternative crop for cool wet regions, are discussed. 相似文献
30.
Testicular seminoma associated with torsion of the spermatic cord in two cryptorchid stallions 总被引:1,自引:0,他引:1
R J Hunt W Hay C Collatos E Welles 《Journal of the American Veterinary Medical Association》1990,197(11):1484-1486
Two adult horses had colic attributable to spermatic cord torsion and strangulation of abdominally retained neoplastic testes. Both horses had caudal abdominal soft tissue masses palpable per rectum. One horse was treated successfully by surgical removal of the testis, and the other was euthanatized without treatment. Histopathologic diagnosis of the involved testes was testicular seminoma. Spermatic cord torsion of an abdominally retained testis should be considered in the differential diagnosis of signs of abdominal pain in cryptorchid stallions, especially those with a palpable caudal abdominal mass. 相似文献