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141.
We use trivariate kernel density estimation to define spawning habitat of northern anchovy ( Engraulis mordax ) and Pacific sardine ( Sardinops sagax ) in the California Current using satellite data and in situ egg samples from the Continuous Underway Fish Egg Sampler (CUFES) deployed during surveys in April by the California Cooperative Oceanic Fisheries Investigations (CalCOFI). Observed egg distributions were compared with monthly composite satellite sea surface temperature (SST) and surface chlorophyll a (chl a ) data. Based on the preferred spawning habitat, as defined in SST and chl a space, the satellite data were used to predict potential spawning habitat along two areas of the west coast of North America. Data from the southern area (21.5 to 39°N) were compared to observations from the CUFES data for the period 1998–2005. Northern anchovy and Pacific sardine exhibited distinctly different spawning habitat distributions. A significant relationship was found between satellite-based spawning area and that measured during surveys for sardine. CUFES area estimated for sardine was similar in magnitude to that estimated from satellite data (∼60 000 km2 ). In contrast, spawning habitat of anchovy averaged between 1000 and 200 000 km2 for the period 1998–2005, for CUFES and satellite estimates, respectively. Interannual variability in the area (km2 ) and duration (months) of estimates of suitable habitat varied between species and between the northern (39 to 50.5°N) and southern portions of the California Current. Long-term monitoring of habitat variability using remote sensing data is possible in the southern portion of the California Current, and could be improved upon in the northern area with the addition of surveys better timed to describe relationships between observed and estimated spawning habitats. 相似文献
142.
Van Dover CL Humphris SE Fornari D Cavanaugh CM Collier R Goffredi SK Hashimoto J Lilley MD Reysenbach AL Shank TM Von Damm KL Banta A Gallant RM Gotz D Green D Hall J Harmer TL Hurtado LA Johnson P McKiness ZP Meredith C Olson E Pan IL Turnipseed M Won Y Young CR Vrijenhoek RC 《Science (New York, N.Y.)》2001,294(5543):818-823
Within the endemic invertebrate faunas of hydrothermal vents, five biogeographic provinces are recognized. Invertebrates at two Indian Ocean vent fields (Kairei and Edmond) belong to a sixth province, despite ecological settings and invertebrate-bacterial symbioses similar to those of both western Pacific and Atlantic vents. Most organisms found at these Indian Ocean vent fields have evolutionary affinities with western Pacific vent faunas, but a shrimp that ecologically dominates Indian Ocean vents closely resembles its Mid-Atlantic counterpart. These findings contribute to a global assessment of the biogeography of chemosynthetic faunas and indicate that the Indian Ocean vent community follows asymmetric assembly rules biased toward Pacific evolutionary alliances. 相似文献
143.
A continuous, underway fish egg sampler (CUFES) was employed to assess the abundance and distribution of eggs of both sardine, Sardinops sagax , and round herring, Etrumeus whiteheadi , on the Western Agulhas Bank, South Africa, during September 1996. Samples were collected while underway along six inshore/offshore transects, and at stations along the transects. Volumetric estimates of egg density (eggs m−3 ) from on-station CUFES samples were highly correlated with both volumetric and areal (eggs m−2 ) estimates of egg density from samples collected from CalVET net hauls at these stations, demonstrating the validity of this novel sampling technique. Sardine and round herring eggs were encountered in a band running parallel to the coast and extending from 10 to 30 nautical miles offshore to the shelf edge, and highest egg densities were associated with strong north-west-flowing currents in the region of the shelf edge. Collecting samples while underway increased the precision of the estimate of mean egg density for sardine eggs but not for round herring eggs. The use of CUFES in obtaining a fine-scale resolution of sardine egg distribution, and as a tool for stock assessment, are discussed. 相似文献
144.
Banta JP Lalman DL Owens FN Krehbiel CR Wettemann RP 《Journal of animal science》2006,84(9):2410-2417
This experiment was conducted to determine the effects of interval feeding of whole sunflower seeds on the performance of beef cows and their progeny. During mid to late gestation, 144 multiparous, spring-calving beef cows (588 kg of initial BW; 5.6 initial BCS; 4 to 13 yr old) were individually fed 1 of 3 supplements 4 d/wk for a 76-d period. Supplements (DM basis) included: 1) 0.68 kg of soybean meal/feeding (NCON); 2) 3.01 kg of a soybean hull-based supplement/feeding (PCON); and 3) 1.66 kg of whole sunflower seeds high in linoleic acid/feeding (WSUN). Supplements were formulated to provide similar amounts of CP and ruminally degraded intake protein; PCON and WSUN were also formulated to be isocaloric. During the supplementation period, cows had free-choice access to bermudagrass (Cynodon dactylon) and tall-grass prairie hay. By the end of the 76-d supplementation period, cows fed PCON (P < 0.01) and NCON (P < 0.01) had gained more BW than cows fed WSUN (33, 23, and 10 kg, respectively). However, from the end of this supplementation period to the beginning of the breeding season 84 d later, cows supplemented with PCON had lost more (P < 0.01) BW than cows supplemented with WSUN (-123 kg vs. -111 kg). Cow BW change through weaning (-50 kg, P = 0.43) and final cow BW (536 kg, P = 0.70) at weaning were not different among supplement groups. Furthermore, cow BCS was similar among supplement treatment groups at the end of the supplementation period (5.3, P = 0.09), at the beginning of the breeding season (4.8, P = 0.38), and at weaning (4.7, P = 0.08). No difference among treatments was detected for calf birth weight (36 kg, P = 0.42), calf weaning weight (235 kg, P = 0.67), percentage of cows exhibiting luteal activity at the beginning of the breeding season (57%, P = 0.29), or pregnancy rate (88%, P = 0.44). However, first service conception rate was greater (P = 0.01) for cows fed PCON (79%) and tended (P = 0.07) to be greater for cows fed WSUN (74%) than for cows fed NCON (53%). After weaning, all steer calves were placed in a feedlot and fed a high-concentrate finishing diet for an average of 188 d. Supplements fed to dams during gestation did not influence feedlot performance or carcass characteristics. Prepartum energy supplementation, regardless of energy source or prepartum energy balance, resulted in improved conception rate, but other measures of reproduction, calf and feedlot performance, and carcass characteristics were not affected. 相似文献
145.
CM Volk JW Elkins DW Fahey RJ Salawitch GS Dutton JM Gilligan MH Proffitt M Loewenstein JR Podolske K Minschwaner JJ Margitan KR Chan 《Science (New York, N.Y.)》1996,272(5269):1763-1768
Airborne in situ observations of molecules with a wide range of lifetimes (methane, nitrous oxide, reactive nitrogen, ozone, chlorinated halocarbons, and halon-1211), used in a tropical tracer model, show that mid-latitude air is entrained into the tropical lower stratosphere within about 13.5 months; transport is faster in the reverse direction. Because exchange with the tropics is slower than global photochemical models generally assume, ozone at mid-latitudes appears to be more sensitive to elevated levels of industrial chlorine than is currently predicted. Nevertheless, about 45 percent of air in the tropical ascent region at 21 kilometers is of mid-latitude origin, implying that emissions from supersonic aircraft could reach the middle stratosphere. 相似文献
146.
Three foals aged between 21 and 44 days were presented for evaluation of pyrexia and lameness. Each had subcutaneous abscessation associated with osteomyelitis of a rib at the costochondral junction and pathological fracture of the affected rib; one foal had more than one rib affected. Other localised sites of infection included other sites of osteomyelitis, omphalophlebitis, uveitis, enterocolitis, and calcaneal bursitis. The subcutaneous abscessation and rib osteomyelitis was treated surgically in two foals. Salmonella typhimurium was isolated from the subcutaneous abscess in one foal and from the faeces of another. Two of the three foals were euthanased. Ultrasonography was a more useful modality than radiography for establishing the diagnosis of costal osteomyelitis. 相似文献
147.
Widespread spontaneous evacuation, the tendency for people to evacuate even when not advised to do so, has been highlighted as one of the likely behavioral responses to a nuclear power plant emergency. Utility company representatives contend that protective action advisories can be structured so as to stifle the magnitude and geographic extent of spontaneous evacuation. Data from a utility-company-sponsored telephone survey of households on Long Island, New York, where the Shoreham Nuclear Power Station is located, are used in this paper to test this proposition. Analyses of responses given to three sets of increasingly serious reactor accident scenarios, with and without information instructing people what protective actions to take, raise serious questions about the ability of emergency notification messages to affect human behavior in a radiological emergency. The results suggest firstly, that even if people me specifically advised not to evacuate, most would be inclined to do so; and secondly, that attempts to stifle the propensity to evacuate among those who are not at risk are likely to increase the propensity to stay behind among those who are at risk and should evacuate. 相似文献
148.
Recordings of the middle latency of the auditory evoked potential (MLAEP) were made in eight conscious ponies. These traces were compared to those made under halothane anaesthesia with and without paralysis of the skeletal muscles. Recordings were also made from percutaneous electrodes placed along the neck with the same stimulus used for the auditory evoked potentials. The results of these experiments were used to deduce the origin of latencies in the auditory evoked potential occurring between 10 and 25 ms after the stimulus. The MLAEP was found to contain two positive peaks between the latencies of 10 and 25 ms. The first of these two peaks was not abolished by halothane anaesthesia or muscle paralysis. The second of these two peaks was abolished by halothane anaesthesia in all but one animal. In this animal the second peak was abolished by muscle paralysis. No peaks of corresponding latency were recorded from the percutaneous electrodes except from one electrode position at the caudal neck in one pony. The first peak of the middle latency auditory evoked potential seen in conscious ponies appeared to be of central nervous orign. The second peak appeared to be of muscular origin, possibly from the external auditory muscles. The second peak may be analogous to the post-auricular waveform described in man. 相似文献
149.
A Retrospective Comparison of Three Techniques for Femoral Head and Neck Excision in Dogs 总被引:1,自引:0,他引:1
R. D. MONTGOMERY DVM MS J. L. MILTON DVM MS R. D. HORNE DVM MS R. H. COBLE JR. DVM J. C. WILLIAMS PhD 《Veterinary surgery : VS》1987,16(6):423-426
Femoral head and neck excision was performed in 169 dogs over a 7 year period. A written questionnaire completed by 56 owners, evaluating a total of 72 joints, was the basis for retrospective evaluation of the efficacy of the procedures used. There were four surgical groups: femoral head and neck excision (FHNE) in dogs with body weights over 14 kg, the same procedure in dogs with body weights less than 14 kg (SMALL), femoral head and neck excision with muscle interposition (MI), and the wedge resection technique (WRT). Although differences in results were noted, there were no statistically significant differences between any of the groups for the percentage of leg use during normal activity (p greater than 0.05), mean postoperative time until leg use, use of the leg or hopping while running, or lameness with exercise (p greater than 0.10). The results of this study suggest that there is little advantage in performing the more time-consuming and traumatic muscle interposition and wedge resection procedures. 相似文献
150.
Jill E. Sackman DVM PhD Gregory B. Daniel DVM MS Michael B. Freeman MD Clinton D. Lothrop JR. DVM PhD 《Veterinary radiology & ultrasound》1997,38(2):150-155
Endothelial seeding of vascular grafts has been shown to decrease graft thrombogenicity and prolong longevity when implanted in vivo. Previous studies have utilized anatomic grafts to study endothelialization and healing. Anatomic thoracoabdominal grafts do not allow for sequential biopsy for evaluation of individual grafts nor do they approximate the environment for long bypass grafts used in limb salvage. This study evaluated the use of an extra-anatomic aortic bypass graft to assess the healing of endothelial cell seeded expanded polytetrafluoroethylene (ePTFE). Radionuclide angiography was used to evaluate graft patency and quantify blood flow through the graft. Dogs underwent placement of an extra-anatomic 60 cm long, 8 mm internal diameter, graft seeded with autologous endothelium. Grafts were biopsied from 2 weeks up to 1 year. Radionuclide studies were performed postimplantation and following each graft biopsy. Graft placement and biopsies were well tolerated in all dogs. Biopsied segments of graft allowed for sequential studies of the healing of implanted grafts by scanning electron and light microscopy. Flow through the implanted graft was close to 50% of the total caudal abdominal aortic flow. No significant difference in graft flow was noted either between animals or overtime. 相似文献