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61.
WC Feldman BL Barraclough S Maurice RC Elphic DJ Lawrence DR Thomsen AB Binder 《Science (New York, N.Y.)》1998,281(5382):1489-1493
Global maps of thermal and fast neutron fluxes from the moon suggest three end-member compositional units. A high thermal and low fast neutron flux unit correlates with the lunar highlands and is consistent with feldspathic rocks. The South Pole-Aitken basin and a strip that surrounds the nearside maria have intermediate thermal and fast neutron flux levels, consistent with more mafic rocks. There appears to be a smooth transition between the most mafic and feldspathic compositions, which correspond to low and high surface altitudes, respectively. The maria show low thermal and high fast neutron fluxes, consistent with basaltic rocks. 相似文献
62.
Are extinctions of marine vertebrates as rare and unlikely as current data indicate? Long-term research surveys on the continental shelf between the Grand Banks of Newfoundland and southern New England reveal that one of the largest skates in the northwest Atlantic, the barndoor skate (Raja laevis), is close to extinction. Forty-five years ago, research surveys on St. Pierre Bank (off southern Newfoundland) recorded barndoor skates in 10% of their tows; in the last 20 years, none has been caught, and this pattern of decline is similar throughout the range of the species. 相似文献
63.
RC Elphic DJ Lawrence WC Feldman BL Barraclough S Maurice AB Binder PG Lucey 《Science (New York, N.Y.)》1998,281(5382):1493-1496
The Lunar Prospector neutron spectrometer data correlate well with iron and titanium abundances obtained through analysis of Clementine spectral reflectance data. With the iron and titanium dependence removed, the neutron spectrometer data also reveal regions with enhanced amounts of gadolinium and samarium, incompatible rare earth elements that are enriched in the final phases of magma crystallization. These regions are found mainly around the ramparts of the Imbrium impact basin but not around the other basins, including the much larger and deeper South Pole-Aitken basin. This result confirms the compositional uniqueness of the surface and interior of the Imbrium region. 相似文献
64.
The effects of maturity on grain quality and wet‐milling properties were investigated for two hybrids of corn. Significant differences for hybrid and maturity were observed for all grain quality parameters. Test weight, absolute density, and thousand‐grain weight all increased as the corn matured. Kernel hardness increased and breakage susceptibility varied with increased maturity. Water uptake parameters decreased with maturity of the grain. The starch yield results from wet milling showed that the starch yield increased significantly within each cultivar in the early stages of grain maturity, but there were no significant differences between hybrids. Mathematical models using selected grain quality parameters accurately predicted trends in starch yield for the immature and mature corn samples in this study. 相似文献
65.
Fish assemblage production estimates in Appalachian streams across a latitudinal and temperature gradient 下载免费PDF全文
Bonnie J.E. Myers C. Andrew Dolloff Jackson R. Webster Keith H. Nislow Brandon Fair Andrew L. Rypel 《Ecology of Freshwater Fish》2018,27(1):363-377
Production of biomass is central to the ecology and sustainability of fish assemblages. The goal of this study was to empirically estimate and compare fish assemblage production, production‐to‐biomass (P/B) ratios and species composition for 25 second‐ to third‐order streams spanning the Appalachian Mountains (from Vermont to North Carolina) that vary in their temperature regimes. Fish assemblage production estimates ranged from 0.15 to 6.79 g m?2 year?1, and P/B ratios ranged from 0.20 to 1.07. There were no significant differences in mean assemblage production across northern cold‐water, southern cold‐water and southern cool‐water streams (p = .35). Two warm‐water streams, not included in these comparisons, had the highest mean production and biomass values. Mean assemblage P/B was significantly higher in northern cold‐water streams relative to southern cold‐water and cool‐water streams (p = .01). Species evenness in production declined with stream temperature and differed significantly across the lower latitude cold‐water, cool‐water and warm‐water streams and the higher latitude (i.e. more northern) cold‐water streams. Our fish assemblage production estimates and P/B ratios were both lower and higher compared to previously published estimates for similar stream habitats. This study provides empirical fish assemblage production estimates to inform future research on southern Appalachian streams and on the potential impacts of varying temperature regimes on cold‐water, cool‐water and warm‐water fish production in the coming decades as climate change continues to threaten fish assemblages. 相似文献
66.
Myers CJ Magdesian KG Kass PH Madigan JE Rhodes DM Marks SL 《Veterinary journal (London, England : 1997)》2009,181(2):137-144
This retrospective study describes the use of and complications associated with parenteral nutrition (PN) administration to 53 equine neonates at the University of California Veterinary Medical Teaching Hospital. Medical records were examined and information obtained on signalment, physical examination, clinical diagnosis, outcome, total hospitalization time, insulin administration, microbiology culture results, other complications (i.e. thrombophlebitis) and necropsy findings. Complete blood count and serum biochemistry analytes, venous blood gas, serum electrolyte and glucose concentrations, and blood lactate concentration results were compared before and during PN administration in all foals. Seventeen foals (32%) developed hypertriglyceridemia (>200mg/dL). Triglyceride concentrations >200mg/dL were significantly (P=0.049) associated with non-survival. Forty-seven foals (89%) developed hyperglycemia (blood glucose >120mg/dL) and eight (15%) developed catheter-related complications (thrombosis or local sepsis). Packed cell volume, total protein, creatinine, blood urea nitrogen, and sorbitol dehydrogenase concentrations decreased while foals were on PN, while serum chloride concentration increased. This study highlighted that hypertriglyceridemia during the acute phase of neonatal illness may be detrimental to outcome, and that the safety of lipid-containing solutions in foals warrants further study. 相似文献
67.
Wohlmuth H Smith MK Brooks LO Myers SP Leach DN 《Journal of agricultural and food chemistry》2006,54(4):1414-1419
Ginger oil, obtained by steam distillation of the rhizome of Zingiber officinale Roscoe, is used in the beverage and fragrance industries. Ginger oil displays considerable compositional diversity, but is typically characterized by a high content of sesquiterpene hydrocarbons, including zingiberene, ar-curcumene, beta-bisabolene, and beta-sesquiphellandrene. Australian ginger oil has a reputation for possessing a particular "lemony" aroma, due to its high content of the isomers neral and geranial, often collectively referred to as citral. Fresh rhizomes of 17 clones of Australian ginger, including commercial cultivars and experimental tetraploid clones, were steam distilled 7 weeks post-harvest, and the resulting oils were analyzed by GC-MS. The essential oils of 16 of the 17 clones, including the tetraploid clones and their parent cultivar, were found to be of substantially similar composition. These oils were characterized by very high citral levels (51-71%) and relatively low levels of the sesquiterpene hydrocarbons typical of ginger oil. The citral levels of most of these oils exceeded those previously reported for ginger oils. The neral-to-geranial ratio was shown to be remarkably constant (0.61 +/- 0.01) across all 17 clones. One clone, the cultivar "Jamaican", yielded oil with a substantially different composition, lower citral content and higher levels of sesquiterpene hydrocarbons. Because this cultivar also contains significantly higher concentrations of pungent gingerols, it possesses unique aroma and flavor characteristics, which should be of commercial interest. 相似文献
68.
Debbie A. Myers Chris D. Smith Ellis C. Greiner Ellen Wiedner Jeffrey Abbott Rosanna Marsella Catherine Nunnery 《Veterinary dermatology》2010,21(5):527-530
A 6‐year‐old castrated dromedary camel (Camelus dromedarius) presented with a non‐healing, severely pruritic, ulcerative fibrotic plaque located at the medial canthus. Histological examination of surgical biopsies identified degenerating nematode larvae within eosinophilic granulomas. Treatment involved repeated debridement of the lesion, injectable ivermectin and anti‐inflammatory therapies, and injectable and topical antibiotics . A specially constructed mask with goggles to prevent the camel from continuing to self‐traumatize the eye and lesion was also placed. Full recovery occurred approximately 1 month after diagnosis. Because of the location of the lesion, time of year, the gross and microscopic characteristics of the lesion, the presence of a likely nematode larva and the response to treatment, a diagnosis of cutaneous habronemiasis was made. 相似文献
69.
Hazel Wetzstein S. C. Myers 《The Journal of Horticultural Science and Biotechnology》2013,88(4):747-753
SUMMARYEvaluations were made of the field performance of micropropagated (tissue cultured axillary buds) versus conventionally rooted softwood cuttings of muscadine grape, Vitis rotundifolia Michx. Trunk cross-sectional area did not differ between treatments during three years of field evaluation following planting. There were no differences in leaf area and dry weight or shoot number in the two propagation types; leaf morphology was normal with no apparent juvenile characteristics. Yield components including flower number per shoot and inflorescence, fruit number, total fruit weight and yield efficiency were greater in micropropagated plants during the second year, the first year of cropping; differences diminished and yield components were not different in year three. Performance of tissue cultured plants was therefore as good as, or surpassed, conventionally propagated plants during early vine establishment. 相似文献
70.
Janzen AM Wiles D Myers S Marqués FJ 《The Canadian veterinary journal. La revue veterinaire canadienne》2011,52(12):1345-1349
A juvenile Cashmere goat was evaluated and treated for generalized pustular and crusting dermatitis. A diagnosis of pemphigus foliaceus was made based on histopathology and immunohistochemistry. Treatment with prednisolone resulted in resolution of the lesions. Despite tapering doses and combination with methylprednisolone for monthly maintenance, the kid was euthanized for poor growth and fiber quality. 相似文献