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191.
A. P. Walker P. K. Mutuo M. van Noordwijk A. Albrecht G. Cadisch 《Agroforestry Systems》2007,70(3):197-209
Poor soil fertility is the biggest obstacle to agricultural productivity in Sub-Saharan Africa. Improved fallows can help
to raise agricultural productivity in these systems of low financial capital, however, experimental testing of their potential
application domain and design is costly and time consuming. Models can evaluate alternative systems relatively quickly and
at relatively low cost, but must first be validated to assess satisfactory simulation of the target systems. Specific climatic,
edaphic, crop and fallow growth data was used from five sites in Western Kenya to calibrate and validate simulations of maize
and improved fallow growth using the Water, Nutrient and Light Capture in Agroforestry Systems (WaNuLCAS) model. The model
predicted continuous maize yields across the sites with an R
2
of 0.72, an EF (model efficiency) of 0.66 and a CD (coefficient of determination) of 2.73, although the default pedotransfer
functions (PTF) for volumetric soil water content used in the model had to be substituted for a tropical soils specific PTF
before this was achieved. Predicted maize yield was consistently related to fallow biomass (i.e. higher fallow biomass correlated
with higher subsequent maize yields) at two sites and the model predicted maize yields following fallow growth from this subset
of the data with an R
2
of 0.42. This relationship of fallow biomass to subsequent maize yield was not observed across the whole data set due to
incomplete fallow litterfall data, factors not included in the model and associated poor model prediction of recycled tree
biomass. After site and tree calibration, the model can thus be applied to assess fallow management strategies for sites limited
by water and nitrogen. 相似文献
192.
James L. Cook Kurt S. Schulz G. Josh Karnes Samuel P. Franklin Sherman O. Canapp Jr. Peter J. Lotsikas Noel Fitzpatrick Jason L. Wheeler Kevin S. Stiffler Mitchell Gillick Alan R. Cross Charles M. Walls Mark R. Albrecht Ned Williams David T. Crouch Daniel D. Lewis Antonio Pozzi Patrick Ridge 《The Canadian veterinary journal. La revue veterinaire canadienne》2015,56(9):971-977
We evaluated mid- to long-term outcomes with respect to function and complications in dogs undergoing canine unicompartmental elbow (CUE) arthroplasty for treatment of medial compartment disease of the elbow. This prospective multicenter case series is the first group of clinical cases to receive CUE arthroplasty. Cases (each elbow that underwent CUE performed by a participating surgeon) were enrolled into an electronic database and prospectively followed to determine and record all associated complications, as well as functional outcomes. There were 103 cases from 18 surgeons. Final follow-up time ranged from 6 to 47 mo with a mean and median of 10 mo. Canine unicompartmental elbow was associated with 1 catastrophic (1%), 11 major (10.7%), and 28 minor (27.2%) complications. Outcomes following CUE were reported as full function in 49 cases (47.6%), acceptable function in 45 cases (43.7%), and unacceptable function in 9 cases (8.7%). We conclude that CUE arthroplasty is an appropriate consideration for treatment of medial compartment disease of the elbow in dogs. 相似文献
193.
Albrecht Hase 《Journal of pest science》1932,8(7):73-82
Ohne Zusammenfassung
Mit 5 Abbildungen. 相似文献
194.
Albrecht Hase 《Journal of pest science》1939,15(12):133-142
Ohne Zusammenfassung
Mit 11 Abbildungen 相似文献
195.
Albrecht Hase 《Journal of pest science》1939,15(8):95-96
196.
Aerosols, cloud microphysics, and fractional cloudiness 总被引:16,自引:0,他引:16
Albrecht BA 《Science (New York, N.Y.)》1989,245(4923):1227-1230
Increases in aerosol concentrations over the oceans may increase the amount of low-level cloudiness through a reduction in drizzle-a process that regulates the liquid-water content and the energetics of shallow marine clouds. The resulting increase in the global albedo would be in addition to the increase due to enhancement in reflectivity associated with a decrease in droplet size and would contribute to a cooling of the earth's surface. 相似文献
197.
L Sch?berlein K Renatus G von Lengerken H Hennebach V Albrecht 《Archiv fuer experimentelle veterinaermedizin》1979,33(3):337-345
The following methods of insensitisation were tested for their effects on muscle pork quality: Electrocoma, 75 V, 15 sec; Electrocoma following intensive electrical stimulation and irritation of various parts of the animals's body, using the insensitising forceps; Dart gun insensitisation. Also tested was the action of muscle relaxants on pork quality. Minor deviation from proper practice of electrical insensitisation was found to cause no significant deterioration in cutlet muscle and ham muscle quality. However, intensive irritation immediately before insensitisation caused higher percentages of PSE (16.7 per cent) and DFD (16.7 per cent). Dart gun insensitisation was quite often followed by poorer quality in the form of watery and bright pork (25.0 per cent). This had detrimental consequences for boiled ham processing (higher loss rates). Sensorial assessment of boiled ham obtained from animals in various categories did not reveal any significant discrepancy between the above techniques. When muscle relaxants were used, muscle pork quality of pigs relaxed by means of succicholine dichloride was much better than that in animals to which electrical insensitisation had been applied. Characteristics of such better quality included slower decline in pH over 45 minutes after death and lower drip loss. 相似文献
198.
Polar lipids of archaebacteria in sediments and petroleums 总被引:1,自引:0,他引:1
Glycerol tetraethers with head-to-head isoprenoid 40-carbon chains that are typical of archaebacteria, in particular of methanogens, were identified in the polar lipids of sediments and petroleums. These structures are at least partially preserved in the subsurface beyond the stage of petroleum formation. Their identification provides further evidence that a significant part of geological organic matter derives from the lipids of membranes of microorganisms. 相似文献
199.
Volker Mohler Theresa Albrecht Kolumbina Mrva Günther Schweizer Lorenz Hartl 《Plant Breeding》2014,133(4):448-453
The objective of the present study was to analyse the genetic basis of falling number in three winter wheat populations. Samples for falling number determination for each population originated from at least three test environments that were free from the occurrence of preharvest sprouting at harvest time. Quantitative trait locus (QTL) analysis employing falling number values from single environments identified eight, five and three QTL in the populations Dream/Lynx, Bussard/W332‐84 and BAUB469511/Format, respectively. A major QTL common to all three populations and consistently detected in each environment mapped to the long arm of chromosome 7B. The QTL was located to a similar genomic region as the previously described major QTL for high‐isoelectric point α‐amylase content. The T1BL.1RS wheat‐rye translocation and the dwarfing gene Rht‐D1 segregating in Dream/Lynx and BAUB469511/Format were found to be important factors of falling number variation. In both populations, the presence of Rht‐D1b or the absence of T1BL.1RS increased falling number. The results indicate that late maturity α‐amylase, responsible for low falling numbers, has now been documented in German wheat germplasm. 相似文献
200.
Jadwiga Andrzejewska Francisco E. Contreras-Govea Anna Pastuszka Kenneth A. Albrecht 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2016,66(6):516-522
Kura clover (Trifolium ambiguum M. Bieb.) is a rhizomatous perennial legume that is native to Caucasia, is extremely persistent in North America, but its performance has not been adequately evaluated in Europe. The objective of this research was to compare forage yield and nutritive value of Kura clover to lucerne (Medicago sativa L.), red clover (Trifolium pretense L.) and white clover (Trifolium repens L.) at two locations in Poland. All clover stands thinned markedly by spring of the second production year because of infection by Sclerotinia crown and stem rot, but lucerne stands remained dense and this legume produced the highest total yield over 3 or 4 production years. Kura clover yields of 7.2–8.3?Mg?ha?1 were second to lucerne by the third production year but long-term performance was diminished by stand thinning. Kura clover and white clover had lower fiber concentrations and greater protein concentrations and forage digestibility than red clover and lucerne. Kura clover can be a source of high-quality forage in Europe, but cannot be recommended for use in areas with known Sclerotinia trifoliorum presence until resistance to this pathogen is developed. 相似文献