Chemical Examination of a Core from Lake Zeribar, Iran     

Hutchinson GE  Cowgill UM 《Science (New York, N.Y.)》1963,140(3562):67-69

Chemical studies indicate that during the first half of the history of Lake Zeribar, since about 14,800 years ago, the outlet ran very intermittently, thus resulting in a carbonate deposition and a moderate chloride content of the water. The later sediments are largely littoral and cannot easily be interpreted. A fall in exchangeable potassium at the top is probably correlated with the development of extensive beds of aquatic macrophytes. The data appear to be in harmony with those derived from pollen analysis.  相似文献   

Atmospheric ammonia: absorption by plant leaves   总被引：12，自引：0，他引：12  

G L Hutchinson  R J Millington  D B Peters 《Science (New York, N.Y.)》1972,175(23):771-772

By monitoring the disappearance of ammonia from an airstream flowing through a small growth chamber containing a single plant seedling, it was discovered that plant leaves absorb significant quantities of ammonia from the air, even at naturally occurring low atmospheric concentrations. The measured absorption rates of ammonia showed large diurnal fluctuations and varied somewhat among species, but differed little with the nitrogen fertility level of plants within a species.  相似文献   

Widespread monoallelic expression on human autosomes     

Gimelbrant A  Hutchinson JN  Thompson BR  Chess A 《Science (New York, N.Y.)》2007,318(5853):1136-1140

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Sustainability. USGS goals for the coming decade     

Myers MD  Ayers MA  Baron JS  Beauchemin PR  Gallagher KT  Goldhaber MB  Hutchinson DR  Labaugh JW  Sayre RG  Schwarzbach SE  Schweig ES  Thormodsgard J  van Riper C  Wilde W 《Science (New York, N.Y.)》2007,318(5848):200-201

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Compost Maturity Effects on Nitrogen and Carbon Mineralization and Plant Growth     

T.S. Griffin  M. Hutchinson 《Compost science & utilization》2013,21(4):228-236

Improved predictive relationships between compost maturity and nitrogen (N) availability are needed. A total of 13 compost samples were collected from a single windrow over a 91 d period. Compost stability and maturity were assessed using both standard chemical analyses (total C and N, mineral N, total volatile solids) and other methods (CO₂ evolution, commercial maturity kits, and neutral detergent fiber, and lignin). Compost N and carbon (C) were evaluated during a 130 d aerobic incubation in a sandy loam soil after each compost was applied at 200 mg total kg^?1 soil. The effect of compost maturity on plant growth was evaluated by growing two ryegrass (Lolium perenne L.) crops and one barley (Hordeum vulgare L.) crop in succession in compost-amended soil under greenhouse conditions. Potential phytotoxicity from compost was assessed by growing tomato (Lypersicum esculentum L.) seedlings in compost-amended soil. Regression and correlation analyses were used to evaluate the relationship between compost maturity parameters, the rate and extent of net N and C mineralization, plant yield and N uptake, and phytotoxicity. Commonly used maturity parameters like total C, total N, and C:N ratio were poorly correlated with the rate and extent of mineralization, and with plant growth parameters. The N mineralization rate during the first 48 d of aerobic incubation was strongly correlated (r= ?0.82 to ?0.86) to compost fiber and lignin concentration, and to the Maturity Index (r=0.85). Trends in C mineralization were similar. There were few differences in C mineralization between composts after 48 d of aerobic incubation in soil. Ryegrass harvested 35 and 70 d after compost application was not strongly affected by compost maturity, and relatively immature composts were phytotoxic to tomato seedlings. Methods of characterizing compost maturity and stability that more realistically reflect the composting process are better predictors of N release and potential plant inhibition after incorporation into soil.  相似文献   

Self-mode-locking of quantum cascade lasers with giant ultrafast optical nonlinearities     

Paiella R  Capasso F  Gmachl C  Sivco DL  Baillargeon JN  Hutchinson AL  Cho AY  Liu HC 《Science (New York, N.Y.)》2000,290(5497):1739-1742

We report on the generation of picosecond self-mode-locked pulses from midinfrared quantum cascade lasers, at wavelengths within the important molecular fingerprint region. These devices are based on intersubband electron transitions in semiconductor nanostructures, which are characterized by some of the largest optical nonlinearities observed in nature and by picosecond relaxation lifetimes. Our results are interpreted with a model in which one of these nonlinearities, the intensity-dependent refractive index of the lasing transition, creates a nonlinear waveguide where the optical losses decrease with increasing intensity. This favors the generation of ultrashort pulses, because of their larger instantaneous intensity relative to continuous-wave emission.  相似文献   

Mr Dick Powell: an appreciation     

M. Hutchinson 《Grass and Forage Science》2004,59(4):309-309

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Interfirm comparisons     

J.D. Hutchinson 《New Zealand veterinary journal》2013,61(10):244-245

Interfirm comparisons are a method of assisting business firms and other organisations to improve their efficiency and profitability.

Interfirm comparisons (IFC) adjust your financial accounts to allow for anomalies which distort the figures from a managerial decision-making point of view. A full IFC survey provides useful and meaningful information for the individual participant, and for the industry, which is not available from any other source. Decisions then need to be made in order to develop a sound set of strategies and plans that will result in a formal budget based on the IFC study. The results discussed in this paper are not adjusted, and they are from a small sample survey only.  相似文献   

Distribution of glutathione peroxidase activity and selenium in the blood of dairy cows.   总被引：1，自引：0，他引：1  

R W Scholz  L J Hutchinson 《American journal of veterinary research》1979,40(2):245-249

The distribution of glutathione peroxidase (GSH-Px) activity and selenium concentrations among several components in the blood of dairy cows was examined. Approximately 98% of the GSH-Px activity in peripheral blood was associated with the erythrocytes when enzyme activity was expressed as units per milliliter of blood. The GSH-Px activity expressed per cell was approximately fourfold greater for peripheral leukocytes than for erythrocytes. The cellular component contained a greater proportion (approx 73%) of whole blood selenium than did the plasma. A positive linear relationship (r = 0.958) between blood GSH-Px activity and blood selenium concentrations was found in dairy cattle under practical field conditions.  相似文献   

Factors affecting shoot proliferation and root initiation in organ cultures of the apple ‘Northern Spy’     

James F. Hutchinson 《Scientia Horticulturae》1984,22(4):347-358

Factors affecting the establishment, proliferation and adventitious root initiation of ‘Northern Spy’ are described. Shoot-tips established best in Linsmaier and Skoog medium with 5 μM BAP and 1 μM IBA supplemented with 1 mM phloroglucinol, but after the fourth sub-culture, proliferation was similar in media without phloroglucinol. Shoot proliferation was influenced by cytokinin type and concentration, light level and ex-plant type. Of the cytokinins tested, BAP was superior to zeatin, kinetin and 2iP. Proliferation was better with 10 μM BAP than with 5 or 1 μM BAP, but at 10 μM shoots were dwarfed. Single nodes and basal mass expiants produced significantly more shoots than did shoot-tips. Shoot proliferation was maximum at photon flux densities of 75 μmolm^?2s^?1. Roots can be readily induced with IBA, but salt concentration and the physical support on which shoot-tips are grown influence both root initiation and growth. Half-strength salts and 1 μM IBA gave best root initiation. With agar, coarse sand, perlite and rotated liquid medium, 90–100% root initiation occurs, but root growth was poor in agar.  相似文献