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71.
Reusser LJ Bierman PR Pavich MJ Zen EA Larsen J Finkel R 《Science (New York, N.Y.)》2004,305(5683):499-502
The direct and secondary effects of rapidly changing climate caused large rivers draining the Atlantic passive margin to incise quickly into bedrock beginning about 35,000 years ago. Measured in samples from bedrock fluvial terraces, 10-beryllium shows that both the Susquehanna and Potomac Rivers incised 10- to 20-meter-deep gorges along steep, convex lower reaches during the last glacial cycle. This short-lived pulse of unusually rapid down-cutting ended by 13,000 to 14,000 years ago. The timing and rate of downcutting are similar on the glaciated Susquehanna and unglaciated Potomac Rivers, indicating that regional changes, not simply glacial meltwater, initiated incision. 相似文献
72.
Soluble plutonium is oxidized to the Pi(VI) oxidation state by chlorine during water treatment. Under certain conditions Pi(VI) is readily absorbed from the gastrointestinal tract. It appears that due consideration has not been given to the effect that the presence of plutonium in this oxidation state may have on the maximum permissible concentration of plutonium in drinking water. 相似文献
73.
The volume transport of the Florida Current is determined from the motionally induced voltage difference between Florida and Grand Bahama Island. Simultaneous measurements of potential differences and of volume transport by velocity profiling have a correlation of 0.97. The calibration factor is 25+/- 0.7 sverdrups per volt, and the root-mean-square discrepancy is 0.7 sverdrup. The induced voltage is about one-half the open-circuit value, implying that the conductance of the sediments and lithosphere is about equal to that of the water column. 相似文献
74.
75.
兰州市生态农业旅游开发 总被引:4,自引:1,他引:4
系统分析了兰州市发展生态农业旅游的有利条件、开发现状和存在问题,提出了发展兰州市生态农业旅游的建议。 相似文献
76.
S Backhaus SV Pereverzev A Loshak JC Davis RE Packard 《Science (New York, N.Y.)》1997,278(5342):1435-1438
Direct measurements of the current-phase relation, I versus Deltaphi, for a weak link coupling two reservoirs of B-phase superfluid helium-3 (3He-B) were made over a wide range of temperatures. The weak link consists of a square array of 100-nanometer-diameter apertures. For temperatures T such that T/Tc >/= 0.6 (where Tc is the superfluid transition temperature), I approximately sin(Deltaphi). At lower temperatures, I(Deltaphi) approaches a straight line. Several remarkable phenomena heretofore inaccessible to superconducting Josephson junctions, including direct observation of quantum oscillations and continuous knowledge of Deltaphi, were also observed. 相似文献
77.
J.B. Million J.T. Ritchie T.H. Yeager C.A. Larsen C.D. Warner J.P. Albano 《Scientia Horticulturae》2011
Container Crop Resource Optimization Program (CCROP) is an integrative model which simulates the growth and water and nutrient requirements of a woody ornamental shrub grown in small (2.8–11.4 L) containers in a field environment with overhead sprinkler irrigation. The model was developed for producers, producer advisers and researchers to support best management practice decision-making in container nursery production. We describe the primary processes simulated by CCROP particularly how they differ from traditional crops grown in-ground and assess the ability of CCROP to simulate measured values for a range of irrigation and fertilizer trials and transplanting dates. Results of model testing with 11 trials indicate that CCROP provided reasonable outcomes for biomass and leaf area growth as well as evapotranspiration, runoff (container drainage plus un-intercepted irrigation and rainfall) and nitrogen loss. 相似文献
78.
A 19-yr-old intact male Coquerel's sifaka (Propithecus coquereli) was evaluated for a crusting facial dermatopathy. Fungal culture and histopathology of skin biopsies were consistent with dermatophytosis caused by Trichophyton mentagrophytes, and treatment with the antifungal medication terbinafine was initiated. After 1 mo of treatment, all clinical signs had resolved and a fungal culture of the skin was negative. The sifaka was treated with terbinafine for a total of 81 days. Two additional fungal cultures were taken and found to be negative for the presence of dermatophytes, the last culture being taken 1 mo after discontinuation of terbinafine. To the authors' knowledge, this is the first reported case of dermatophytosis in a prosimian species and the first reported treatment of a prosimian with the antifungal drug terbinafine. 相似文献
79.
Wild ring-tailed lemurs (Lemur catta) can be anesthetized with Telazol via blow dart, but improved techniques are needed so that each lemur is reliably induced with a single dart. Medetomidine-butorphanol (MB) is a good supplemental protocol to be administered once the lemurs are captured, but other protocols may provide longer periods of sedation and immobility. One possible way of increasing the efficacy of each dart is to increase the time it is retained in the leg. In this investigation, a "double-sleeve" technique was used to try to increase the time of dart retention. This technique used a standard silicone sleeve on the needle, along with a second sleeve at the needle hub. Induction values were compared between lemurs darted with double-sleeve needles and those induced with needles that each had a single silicone sleeve. Once the lemurs were induced, supplementation with MB (0.04 mg/kg and 0.2 mg/kg) was compared with supplementation with ketamine-medetomidine (KM) (10 mg/ kg and 0.04 mg/kg). Twenty-three lemurs were darted with Telazol by using single-sleeve needles, and 24 were darted with double-sleeve needles. The number of darts per lemur and number of escapes were not different between animals darted with a single sleeve compared with a double-sleeve; thus, there were no significant improvements in induction success with the double-sleeve technique. Adequate sedation and muscle relaxation were achieved with both MB and KM; however, lemurs that received MB were more relaxed and needed fewer additional supplements that those that received KM. Single-sleeve dart needles are recommended for Telazol induction of ring-tailed lemurs via blow dart and MB is preferable to KM for supplemental sedation and muscle relaxation. 相似文献
80.