Sectional notes     

Frank E. Garrett  David N. Wright  Cecil W. Frutchey  W. B. Ward  Allen Purdy  John C. Campbell  H. J. Evans  C. A. Henderson  W. C. Barnes  John Noonan  Edwin W. Cake  Claude R. Kemper  R. E. Goodwin  J. W. Scannell 《American Journal of Potato Research》1948,25(5):192-208

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Sectional notes     

Frank Garrett  A. H. Eddins  Verne C. Beverly  Marx Koehnke  John C. Campbell  H. J. Evans  W. C. Barnes  John Noonan  Edwin W. Cake  Fred J. Martin  R. E. Goodin  C. L. Fitch 《American Journal of Potato Research》1948,25(4):134-146

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Sectional notes     

Frank E. Garrett  M. A. Lindsay  Elmo Ragsdale  W. B. Ward  John B. Gardner  Verne C. Beverly  H. A. Reilley  J. C. Campbell  W. G. Evans  E. B. Tussing  Avery E. Rich  John Noonan  Harold S. Schaad 《American Journal of Potato Research》1947,24(4):126-140

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Sectional notes     

L. M. Ware  Frank Garrett  M. A. Lindsay  Elmo Ragsdale  John R. Robertson  W. B. Ward  Verne C. Beverly  Marx F. Koehnke  J. C. Campbell  Henry R. Talmage  A. H. Henderson  W. C. Barnes  John Noonan  Chas D. Gaines 《American Journal of Potato Research》1946,23(6):234-246

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Sectional notes     

L. M. Ware  Frank Garrett  W. B. Ward  Marx Koehnke  John C. Campbell  C. A. Henderson  E. R. Jackman 《American Journal of Potato Research》1946,23(2):64-72

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A 0.5-million-year record of millennial-scale climate variability in the north atlantic   总被引：8，自引：0，他引：8  

JF McManus  DW Oppo  JL Cullen 《Science (New York, N.Y.)》1999,283(5404):971-975

Long, continuous, marine sediment records from the subpolar North Atlantic document the glacial modulation of regional climate instability throughout the past 0.5 million years. Whenever ice sheet size surpasses a critical threshold indicated by the benthic oxygen isotope (delta18O) value of 3.5 per mil during each of the past five glaciation cycles, indicators of iceberg discharge and sea-surface temperature display dramatically larger amplitudes of millennial-scale variability than when ice sheets are small. Sea-surface temperature oscillations of 1 degrees to 2 degreesC increase in size to approximately 4 degrees to 6 degreesC, and catastrophic iceberg discharges begin alternating repeatedly with brief quiescent intervals. The glacial growth associated with this amplification threshold represents a relatively small departure from the modern ice sheet configuration and sea level. Instability characterizes nearly all observed climate states, with the exception of a limited range of baseline conditions that includes the current Holocene interglacial.  相似文献   

Disc extrusion in a Rottweiler dog with caudal cervical spondylomyelopathy after failure of intervertebral distraction/stabilisation     

AM MARCHEVSKY  JL RICHARDSON 《Australian veterinary journal》1999,77(5):295-297

A Rottweiler dog was presented with an 8 week history of hindlimb ataxia. Neurological examination localised the lesion to the cervical spinal cord. Myelography demonstrated dynamic compressive lesions at C5-6 and C6-7 consistent with a diagnosis of caudal cervical spondylomyelopathy. Distraction/stabilisation of both discs was performed using interbody polymethyl methacrylate. Both implants subsequently failed leading to extrusion of the remaining dorsal annulus fibrosus of the C5-6 intervertebral disc and nonambulatory tetraparesis. A ventral slot combined with distraction/stabilisation using screws and polymethyl methacrylate was performed and resulted in nearly full neurological recovery.  相似文献   

Shade effects on forage crops with potential in temperate agroforestry practices     

C. H. Lin  R. L. McGraw  M. F. George  H. E. Garrett 《Agroforestry Systems》1998,44(2-3):109-119

Thirty forages, including eight introduced cool-season grasses, four native warm-season grasses, one introduced warm-season grass, eight introduced cool-season legumes, five native warm-season legumes, and four introduced warm-season legumes, were grown in 7.6 L (two gallon) pots in full sun, 50%, and 80% shade created by shade cloth over a greenhouse frame. Experiments were conducted during summer--fall 1994, spring--early summer 1995, and summer--fall 1995. A complete randomized experimental design was used and above ground dry weight was measured in each shade environment. Tukey's studentized range test was used to compare mean dry weights (MDW) within a species. Warm-season grasses displayed significant reductions in MDW under shade regardless of growing season. All cool-season forages grown during spring--early summer showed a decrease in MDW under shade; however, the reductions in dry weights of ‘Benchmark’ and ‘Justus’ orchardgrass, ‘KY 31’ tall fescue, Desmodium canescens and D. paniculatum were not significant under 50% shade. Cool-season grasses showed more shade tolerance when grown during the summer--fall than when grown during the spring--early summer. Seven of the selected cool-season grasses grown during the summer--fall did not display significant reductions in MDW under 50% shade as compared to full sun. Smooth bromegrass grown under 50% shade showed a significantly increased MDW production compared to growth in full sun. With the exception of Justus orchardgrass and smooth bromegrass, growth of cool-season grasses was inhibited at 80% shade. Among the legumes harvested during the fall, the dry weights of both Desmodium species tested and hog peanut (Amphicarpaea bracteata L.) increased significantly under 50% and 80% shade. In addition, ‘Cody’ alfalfa, white clover, slender lespedeza and ‘Kobe’ lespedeza showed no significant reductions in MDW under 50% shade. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

Comparison of continuous and rotational silvopastoral systems for established walnut plantations in southwest Missouri, USA     

J. W. Lehmkuhler  M. S. Kerley  H. E. Garrett  B. E. Cutter  R. L. McGraw 《Agroforestry Systems》1998,44(2-3):267-279

Forty-eight Holstein steers (average weight 243 kg ± 11.8) were utilized to study the performance of cattle grazing a mature walnut stand. Steers were grazed for 56 days in either a continuous (C) or rotational (R) silvopastoral system. Four 0.81 ha pastures were assigned to either the C or R system (two replications per treatment). Initial stocking rates for both treatments were 14.8 animals/ha which was reduced at the mid-point to 7.4 animals/ha. Forage quality, yield, and plant composition were measured weekly throughout the trial. Forage quality differences were determined by neutral detergent fiber (NDF), acid detergent fiber (ADF), and crude protein (CP) measurements. Forage composition was determined by separating material into four categories: grass, legume, weed and dead plant material. Tree response (diameter at breast height and height growth) was measured prior to and following the grazing period. No significant differences were observed for cattle average daily gain between treatments. Forage availability was higher (P > 0.05) for the R treatment. There were no differences for %NDF (P < 0.10) while %ADF was lower (P > 0.10) and %CP tended (P = 0.12) to be higher for R when compared to C. Rotational pastures had higher (P > 0.10) percentages of grass and legume with lower (P > 0.10) percentage dead material. There were no treatment differences (P < 0.10) for tree diameter at breast height. The average height growth for C was 1.67 m while R was 1.19 m which was only numerically different (P = 0.13). It is postulated that differences in height growth were due to increased water competition in R due to increased soil moisture loss by vegetative growth and transpiration. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

Reproductive dominance of pasture trees in a fragmented tropical forest mosaic   总被引：1，自引：0，他引：1  

PR Aldrich  JL Hamrick 《Science (New York, N.Y.)》1998,281(5373):103-105

Tropical forest fragmentation threatens biodiversity, yet basic information on population responses for major groups such as plants is lacking. Hypervariable genetic markers were used to reconstruct a population-level pedigree in fragmented tropical forest for the tree Symphonia globulifera. Though seedlings occurred only in remnant forest, the pedigree showed that most seedlings had been produced by sequentially fewer adults in pasture, creating a genetic bottleneck. The pedigree also implicated shifts in the foraging of animals that disperse pollen and seed in a secondary constriction of the bottleneck. These results suggest that tropical conservation strategies should anticipate complex, cryptic responses to fragmentation.  相似文献