土地使用系统评价：概念和方法论     

Stom.  TJ 薛紫华 《农业科技译丛(杭州)》1994,(2):1-7

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Biotin-pantothenic acid interrelationship and enteritis in the pantothenic acid deficient pig     

COLBY RW  CUNHA TJ 《Journal of the American Veterinary Medical Association》1948,113(861):589-593

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Variation in water relations of black spruce stock types planted in Ontario     

Blake TJ  Sutton RF 《Tree physiology》1987,3(4):331-344

Upland, intermediate and lowland sites in northeastern Ontario were planted between May 28 and June 8 with three types of black spruce (Picea mariana (Mill.) BSP) nursery stock: (1) spring-lifted, 1.5 + 1.5 bareroot plants (BR); (2) 24-week-old, winter-sown, container stock (CWS); and (3) spring-sown, overwintered, container stock (CO). At the beginning of the growing season, the BR stock had the lowest xylem pressure potentials (Psi(x)), stomatal conductances (g(wv)), and net photosynthetic (P(n)) rates. By the end of the growing season, the BR stock still had lower g(wv)s than the container stock types, but had higher shoot Psi(x) values. In August, the turgor loss points for the BR, CO and CWS stock types were -2.8, -1.93 and -1.6 MPa, respectively, while the minimum observed shoot Psi(x) values were -1.4, -1.7 and -1.9 MPa, respectively. The BR stock produced the greatest dry weight of new shoots and unsuberized roots. No new shoots were produced by the CWS stock, but they produced a greater dry weight of unsuberized roots than the CO stock. As a percent of the dry weight of suberized roots, the greatest production of unsuberized roots was by the CWS stock, the least by the BR trees.  相似文献   

Periodicity in tree rings from the corn belt     

Meko DM  Stockton CW  Blasing TJ 《Science (New York, N.Y.)》1985,229(4711):381-384

Previous tree-ring studies indicated that the total area affected by drought in the western United States has rhythmically expanded and contracted over the past 300 years, with a period near the 18.6-year lunar nodal and 22-year double-sunspot cycles. Recently collected tree-ring data from the U.S. Corn Belt for the years 1680 to 1980 were examined for evidence of either of these cycles on a regional scale. Spectral analysis indicated no periodicity in the eastern part of the Corn Belt, but a significant 18.33-year period in the western part. The period length changed from 17.60 to 20.95 years between the first 150 years and the last 151. High-resolution frequency analysis showed that the structure of the 18.33-year spectral peak was complex, with contributions from several frequencies near both the lunar nodal and double-sunspot periods. A t-test of difference of means in reconstructed annual precipitation weakly corroborated a previous finding of an association between drought area and the phase of the double-sunspot cycle. Both the high-resolution frequency analysis and the t-test results indicate that the periodic component of drought near 20 years is too weak and irregular to be of use in drought forecasting for the Corn Belt.  相似文献   

A nutritional myopathy enzootic in a group of yearling beef cattle          下载免费PDF全文

Smith DL  Palmer SJ  Hulland TJ  McSherry BJ  Blackwell TE 《The Canadian veterinary journal. La revue veterinaire canadienne》1985,26(12):385-386,387-390

Steers and bulls under feedlot conditions and on an apparently adequate ration developed transitory signs of diarrhea and unthriftiness. One animal became recumbent. Sick and clinically normal animals in the group had elevated serum creatine kinase and aspartate aminotransferase enzyme values and degenerative changes in muscle fibers on biopsy. Feed analysis was carried out and the animals were monitored over several weeks by means of muscle biopsy and serum enzyme analysis as well as by postmortem examination at slaughter. Subclinical myopathy was found in several animals and was thought to be related to low vitamin E content in the high moisture corn ration.  相似文献   

Cutaneous onchocerciasis in the horse: five cases in southwestern british columbia   总被引：3，自引：3，他引：0  

Lees MJ  Kleider N  Tuddenham TJ 《The Canadian veterinary journal. La revue veterinaire canadienne》1983,24(1):3-5

Five horses were presented because of a dermatitis of the forehead. Unlike previous reports, ventral midline dermatitis was not the major problem, and was present in only two of five cases. All five horses responded to levamisole therapy at a daily dosage of 5.5 g for one week. Owners were cautioned that repeat therapy may be necessary.  相似文献   

Epidural lymphosarcoma with myelomalacia in a seven-year-old Arabian gelding          下载免费PDF全文

Rousseaux CG  Doige CE  Tuddenham TJ 《The Canadian veterinary journal. La revue veterinaire canadienne》1989,30(9):751-753

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Integration of sapflow velocity in elliptical stems     

Hatton TJ  Greenslade D  Dawes WR 《Tree physiology》1992,11(2):185-196

The estimation of water flux through the stem of a plant by point estimates based on the heat pulse technique requires integration of the velocity profile. The polynomial integration method and the weighted average technique both assume radial symmetry about the bole. A method is introduced that solves the equations for the ellipse in the weighted average technique, and includes an optimizing algorithm for the placement of sensors. The sensitivity of sapflow estimates through stems to increasing eccentricity is examined by means of analytical solutions and simulation. The error in sap flux measurement resulting from the radial approximation of the sapwood conducting area is expressed analytically and shown to be small over the range of eccentricities (e < 0.8) expected in nature. Simulations where radial symmetry is assumed for elliptical stems show substantial error in mean velocity (and thus flux) with modest eccentricities (e > 0.4).  相似文献   

The golden bough     

Givnish TJ 《Science (New York, N.Y.)》1994,266(5190):1590-1591

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Views defended by debater          下载免费PDF全文

Hulland TJ 《The Canadian veterinary journal. La revue veterinaire canadienne》1977,18(7):200

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