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21.
Climate and vegetation history of the midcontinent from 75 to 25 ka: A speleothem record from crevice cave, missouri, USA 总被引:3,自引:0,他引:3
Four Missouri stalagmites yield consistent overlapping records of oxygen and carbon isotopic changes and provide a climate and vegetation history with submillennial resolution from 75 to 25 thousand years ago (ka). The thorium-230-dated records reveal that between 75 and 55 ka, the midcontinental climate oscillated on millennial time scales between cold and warm, and vegetation alternated among forest, savanna, and prairie. Temperatures were highest and prairie vegetation peaked between 59 and 55 ka. Climate cooled and forest replaced grassland at 55 ka, when global ice sheets began to build during the early part of Marine Oxygen Isotope Stage 3. 相似文献
22.
Cohen Abigail L. Illan Javier Gutierrez Pfeiffer Vera W. Wohleb Carrie H. Crowder David W. 《Journal of pest science》2022,95(1):315-325
Journal of Pest Science - Long-term monitoring networks that generate data on pest abundance are the foundation of integrated pest management. Monitoring can estimate local risk from pests and... 相似文献
23.
de Campos Mateus Ribeiro Béarez Philippe Amiens-Desneux Edwige Ponti Luigi Gutierrez Andrew Paul Biondi Antonio Adiga Abhijin Desneux Nicolas 《Journal of pest science》2021,94(3):829-842
Journal of Pest Science - The South American tomato pinworm, Tuta absoluta, (SATP) is now a devastating pest worldwide of crops in the family Solanaceae. Most prior studies of SATP’s thermal... 相似文献
24.
Pharmacokinetic variables of amikacin in cows were determined after administration of amikacin sulphate either intravenously (IV) or intramuscularly (IM) at a dose of 25 mg/kg per day for three days. Amikacin concentrations at time zero and maximum serum concentrations were 240.8 microg/mL and 122.53 microg/mL, respectively. The elimination half-life remained unchanged during the three days of administration (T1/2beta = 1.33 +/- 0.029 h for the IV route and T1/2beta = 2.75 +/- 0.38 h for the IM route). Apparent volumes of distribution suggest limited distribution out of the central compartment (VdAUC = 0.154 +/- 0.005 L/kg; Vdc = 36.50 +/- 2.35 L; Vdss = 0.092 +/- 0.004 L/kg). Bioavailability after IM administration was 95%. Serum profiles of urea, creatinine, albumin, electrolytes and pH after 5-day treatment with amikacin at a dose of 25 mg/kg per day IM revealed no changes. Assessment of diffusion of amikacin to milk by a commercially available screening method to detect antibiotic residues revealed that amikacin could not be detected by the fifth milking period after the last treatment. These results suggest that it would be rational to use a large single-daily dose of amikacin for future clinical trials in cows. 相似文献
25.
Rodrigo Gutierrez‐Quintana Julien Guevar Catherine Stalin Kiterie Faller Carmen Yeamans Jacques Penderis 《Veterinary radiology & ultrasound》2014,55(6):585-591
Congenital vertebral malformations are common in brachycephalic “screw‐tailed” dog breeds such as French bulldogs, English bulldogs, Boston terriers, and pugs. The aim of this retrospective study was to determine whether a radiographic classification scheme developed for use in humans would be feasible for use in these dog breeds. Inclusion criteria were hospital admission between September 2009 and April 2013, neurologic examination findings available, diagnostic quality lateral and ventro‐dorsal digital radiographs of the thoracic vertebral column, and at least one congenital vertebral malformation. Radiographs were retrieved and interpreted by two observers who were unaware of neurologic status. Vertebral malformations were classified based on a classification scheme modified from a previous human study and a consensus of both observers. Twenty‐eight dogs met inclusion criteria (12 with neurologic deficits, 16 with no neurologic deficits). Congenital vertebral malformations affected 85/362 (23.5%) of thoracic vertebrae. Vertebral body formation defects were the most common (butterfly vertebrae 6.6%, ventral wedge‐shaped vertebrae 5.5%, dorsal hemivertebrae 0.8%, and dorso‐lateral hemivertebrae 0.5%). No lateral hemivertebrae or lateral wedge‐shaped vertebrae were identified. The T7 vertebra was the most commonly affected (11/28 dogs), followed by T8 (8/28 dogs) and T12 (8/28 dogs). The number and type of vertebral malformations differed between groups (P = 0.01). Based on MRI, dorsal, and dorso‐lateral hemivertebrae were the cause of spinal cord compression in 5/12 (41.6%) of dogs with neurologic deficits. Findings indicated that a modified human radiographic classification system of vertebral malformations is feasible for use in future studies of brachycephalic “screw‐tailed” dogs. 相似文献
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27.
F. H. Gutierrez Boem R. S. Lavado C. A. Porcelli 《Journal of Agronomy and Crop Science》1997,178(3):135-140
Due mainly to alterations in plant metabolism, lack of oxygen and excess salts are disturbances that affect crop yields. In different parts of the world crops are subjected t o those disttirbances, simultaneously or successively. Our objective was to determine the effects of a winter waterlogging followed by a spring salt peak on rapeseed yield, A pot experiment, combining waterlogging and salinization was carried out. The waterlogging duration was: 0 (control), 3, 7 and 14 days and the sahnity treatments were peaks of Electrical Conductivity of 5 and 8 dSm−1 and the control. The yield started decreasingfrotn 3 days during waterlogging, mainly due to the lower number of seeds per plant. The salt peak from 5 dSm−1 affected the yield only in plants which had suffered a waterlogging lower than 7 days, showing interaction between salinity and waterlogging, Only salinity reduced oil content. The saline peak affected the K, Ca and Na concentration in plant tissues, but the effect of salinity on rapeseed could be more related to soil water potential than specific ion toxicities or imbalance. 相似文献
28.
Two populations of common bean, Phaseolus vulgaris L., were used to make three independent location-specific selections at Palmira, Quilichao, and Popayán, Colombia. Also, three across-location selections were made by alternating generations between Palmira and Popayan, between Quilichao and Popayán, and among Palmira, Quilichao, and Popayán. The seven highest yielding lines selected from each environment and population along with 14 parents and two checks were evaluated for seed yield, seed weight, maturity, and reaction to an-thracnose, angular leaf spot, and common bacterial blight. Mean squares due to evaluation and selection environments, selected lines, and their interactions were significant for all traits. Mean yields of selected lines were higher than the mean of parents in both populations. Among location-specific selections, lines yielded higher at their respective selection site. Moreover, selections made at Popayán were higher yielding than those made at Quilichao or Palmira when tested across locations and years. Use of Popayán, a relatively wetter and cooler site, either alone or in combination with other locations resulted in higher yield, higher seed weight, and higher resistance to anthracnose. On the average, location-specific selections were lower yielding than the across-location selections. Among across-location selections, those selected between Palmira and Popayán were the highest yielding in both populations. Selections at Palmira and across all three locations resulted in greater stability. 相似文献
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30.
Keller HU Jorda L Küppers M Gutierrez PJ Hviid SF Knollenberg J Lara LM Sierks H Barbieri C Lamy P Rickman H Rodrigo R 《Science (New York, N.Y.)》2005,310(5746):281-283
The OSIRIS cameras (optical, spectroscopic, and infrared remote imaging system) onboard the European Space Agency's Rosetta spacecraft observed comet 9P/Tempel 1 for 17 days continuously around the time of NASA's Deep Impact mission. The cyanide-to-water production ratio was slightly enhanced in the impact cloud, compared with that of normal comet activity. Dust particles were flowing outward in the coma at >160 meters per second, accelerated by the gas. The slope of the brightness increase showed a dip about 200 seconds after the impact. Dust Afrho values before and long after the impact confirm the slight decrease of cometary activity. The dust-to-water mass ratio was much larger than 1. 相似文献