Improving the timber quality of Sitka spruce through selection and breeding     

Lee  SJ 《Forestry》1999,72(2):123-146

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High-Tc superconductors in the two-dimensional limit:     

JH Choy  SJ Kwon  GS Park 《Science (New York, N.Y.)》1998,280(5369):1589-1592

The free modulation of interlayer distance in a layered high-transition temperature (high-Tc) superconductor is of crucial importance not only for the study of the superconducting mechanism but also for the practical application of high-Tc superconducting materials. Two-dimensional (2D) superconductors were achieved by intercalating a long-chain organic compound into bismuth-based high-Tc cuprates. Although the intercalation of the organic chain increased the interlayer distance remarkably, to tens of angstroms, the superconducting transition temperature of the intercalate was nearly the same as that of the pristine material, suggesting the 2D nature of the high-Tc superconductivity.  相似文献   

Magnetic Field and Plasma Observations at Mars: Initial Results of the Mars Global Surveyor Mission   总被引：2，自引：0，他引：2  

MH Acu?a  JEP Connerney  P Wasilewski  RP Lin  KA Anderson  CW Carlson  J McFadden  DW Curtis  D Mitchell  H Reme  C Mazelle  JA Sauvaud  C d'Uston  A Cros  JL Medale  SJ Bauer  P Cloutier  M Mayhew  D Winterhalter  NF Ness 《Science (New York, N.Y.)》1998,279(5357):1676-1680

The magnetometer and electron reflectometer investigation (MAG/ER) on the Mars Global Surveyor spacecraft has obtained magnetic field and plasma observations throughout the near-Mars environment, from beyond the influence of Mars to just above the surface (at an altitude of approximately 100 kilometers). The solar wind interaction with Mars is in many ways similar to that at Venus and at an active comet, that is, primarily an ionospheric-atmospheric interaction. No significant planetary magnetic field of global scale has been detected to date (<2 x 10(21) Gauss-cubic centimeter), but here the discovery of multiple magnetic anomalies of small spatial scale in the crust of Mars is reported.  相似文献   

Dictionary of Veterinary Epidemiology     

SJ More 《Australian veterinary journal》1999,77(12):813-813

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Isolation of Treponema hyodysenteriae from a wild rat living on a piggery     

DJ HAMPSON  BG COMBS  SJ HARDERS  ID CONNAUGHTON  VA FAHY 《Australian veterinary journal》1991,68(9):308-308

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Presettlement landscape heterogeneity: Evaluating grain of resolution using General Land Office Survey data     

Hazel R. Delcourt  Paul A. Delcourt 《Landscape Ecology》1996,11(6):363-381

General Land Office Survey (GLOS) records from the A.D. 1840s provide data for quantitative characterization of presettlement vegetation across western Mackinac County, Michigan, located within the mixed conifer-northern hardwoods forest region. We analyzed data from land survey plat maps and 1958 bearing, witness, and line trees from 162 surveyed section and quarter-section corners in order to map vegatation cover types at a level of spatial resolution appropriate for characterizing landscape heterogeneity using standard landscape ecological metrics. As also demonstrated by a number of both classic and contemporary plant-ecological studies, the distribution of landforms, soils properties, hydrology, and location of fire breaks all contribute to the heterogeneity in vegetation observed at a landscape scale in the region. Through a series of spatial landscape analyses with differing grain of resolution, in this study we determine that a grid cell size of 65 ha (0.5 mi×0.5 mi or 0.25 mi²) to 259 ha (1 mi²) gives a conservative characterization of landscape heterogeneity using standard metrics and is therefore appropriate for use of GLOS data to study historical landscape changes.  相似文献   

Concentrations of Prolactin, LH, Testosterone, TSH and Thyroxine in Normospermic Dogs of Different Breeds   总被引：1，自引：0，他引：1  

C Urhausen  A Seefeldt  FM Eschricht  A Koch  HO Hoppen  M Beyerbach  C Möhrke  SJ Dieleman  AR Günzel-Apel 《Reproduction in domestic animals》2009,44(S2):279-282

Concentrations of prolactin (PRL), LH, testosterone (T), TSH and thyroxine (T₄) were determined before and at 20, 120 and 180 min after a single iv injection of thyrotropin-releasing hormone (TRH) in eight Beagles, eight Fox Terriers, six Labrador Retrievers and five Great Danes that were normospermic. Mean basal PRL concentrations were lower in the Fox Terriers compared with the Great Danes (p < 0.05). Mean LH concentrations were higher in the Fox Terriers than in the Beagles, and T was lower in the Fox Terriers at some times but not others (p < 0.05). Thyroid Stimulating Hormone (TSH) concentrations did not differ among breeds, while mean basal T₄ values were lower in Fox Terriers compared with Labrador Retrievers and Great Danes (p < 0.05). Stimulation of T₄ secretion 120 and 180 min after iv TRH injection was most pronounced in the Beagles and less in the Fox Terriers (p < 0.05). The results of the present study indicate that potential breed differences in circulating concentrations of PRL, LH, T, TSH and T₄ in male dogs with apparently normal fertility can be encountered, but further studies are needed to determine whether the observed differences are typical features of these breeds, reflect subsets of dogs within breeds, or are in part because of possible uncontrolled parameters such as sample timing, ambient photoperiod, housing conditions or diet.  相似文献   

Extractant ph and the release of phenolic compounds from soils,plant roots and leaf litter     

D.C. Whitehead  Hazel Dibb  R.D. Hartley 《Soil biology & biochemistry》1981,13(5):343-348

The influence of pH was examined, over the range from 6 to 14, on the amounts of p-hydroxybenzoic, vanillic, p-coumaric, ferulic and syringic acids, p-hydroxybenzaldehyde and vanillin, extracted from four soils and associated roots or leaf litter. Adjustment of pH was obtained by the addition of graded amounts of Ca(OH)₂ to water or by 2 m NaOH. The roots associated with three of the soils were from permanent pasture, perennial ryegrass and red clover, while the leaf litter associated with the fourth soil was from beech.The amounts of each phenolic compound extracted increased continuously with increasing pH, from a “threshold” value which varied between pH 7.5 and 10.5. The amounts extracted by water alone from the soil under permanent pasture, at pH 5.8, were equivalent to concentrations in the soil solution ranging from 1.4 μm for p-hydroxybenzoic acid to < 10 nm for ferulie acid. Amounts of up to 2000 times greater than these were extracted by 2 m NaOH. Similar effects of extractant pH were found with the other soils.Comparisons of the amounts of the phenolic compounds extracted from the soils, with the amounts extracted from the associated roots or leaf litter, suggested that substantial proportions of the soil phenolic compounds were either derived from organic residues more than 4 yr old or were the result of microbial synthesis.  相似文献   

Ferripolyphosphate-whey protein powders. Their potential as nutritional iron supplements.     

S B Jones  E B Kalan  T C Jones  J F Hazel  L F Edmondson  A N Booth  J C Fritz 《Journal of agricultural and food chemistry》1975,23(5):981-984

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Impacts of major health conditions affecting the Australian sheepmeat value chain: a review     

E Dal Grande  C Caraguel  SJ Lee  TD Nielsen 《Australian veterinary journal》2021,99(1-2):32-39

Major health conditions in sheep contribute to substantial economic losses throughout the sheepmeat supply chain in Australia. A systematic review was undertaken to explore the measurable impact of six conditions: arthritis, sheep measles, pleurisy, pneumonia, grass seeds and rib fractures, on the production of lamb and mutton across the meat value chain. Peer‐reviewed scientific literature from three databases and non‐peer‐reviewed articles and reports from Australian government and non‐government websites were searched between 11 and 17 November 2019. Original articles, including studies conducted in Australia and New Zealand, that had measurable impacts on conditions of interest were included. The search yielded 16 articles and reports and were classified as producer impact and/or processor impact studies. Mortalities were quantified for pneumonia and arthritis, with pneumonia having the highest impact for producers. Grass seed infestation resulted in the highest impact on carcase and liveweight losses compared to arthritis and pneumonia. Arthritis had the highest trim weight losses for both lamb and mutton and the highest rate of carcase condemnation. Grass seed was the only condition where other impacts on the processor (chain speed and staff relocation to the boning room) were quantified. Although quantifiable production and processing losses were available for some conditions, this review has highlighted that limited quantifiable data based on scientifically sound research were not available for other conditions. The evidence for some conditions found in this review can be used to target future research activities and to further assist producers in making informed management decisions on prevention and control.  相似文献