1,971 research outputs found
Instability of the Ekman Spiral with Applications to the Planetary Boundary Layers
Spiral boundary layer instability applied to planetary boundary layer
LANDSAT menhaden and thread herring resources investigation
The author has identified the following significant results. The most significant achievement is the successful charting of high probability fishing areas from LANDSAT MSS data
LANDSAT follow-on experiment: Gulf of Mexico menhaden and thread herring resources investigation
The author has identified the following significant results. The most significant achievement realized is the successful mapping of high probability fishing areas from LANDSAT MSS data for two Mississippi Sound missions
Multicanonical Parallel Tempering
We present a novel implementation of the parallel tempering Monte Carlo
method in a multicanonical ensemble. Multicanonical weights are derived by a
self-consistent iterative process using a Boltzmann inversion of global energy
histograms. This procedure gives rise to a much broader overlap of
thermodynamic-property histograms; fewer replicas are necessary in parallel
tempering simulations, and the acceptance of trial swap moves can be made
arbitrarily high. We demonstrate the usefulness of the method in the context of
a grand-multicanonical ensemble, where we use multicanonical simulations in
energy space with the addition of an unmodified chemical potential term in
particle-number space. Several possible implementations are discussed, and the
best choice is presented in the context of the liquid-gas phase transition of
the Lennard-Jones fluid. A substantial decrease in the necessary number of
replicas can be achieved through the proposed method, thereby providing a
higher efficiency and the possibility of parallelization.Comment: 8 pages, 3 figure, accepted by J Chem Phy
LANDSAT menhaden and thread herring resources investigation, Gulf of Mexico
The author has identified the following significant results. The most significant achievements thus far include the successful charting of high probability fishing areas from LANDSAT MSS data and the successful simulation of an operational satellite system to provide tactical information for the commercial harvest of menhaden
FEASIBILITY OF A SHEEP COOPERATIVE FOR GRAZING LEAFY SPURGE
This report presents an economic feasibility study of a 5,000 head, cooperatively owned, sheep operation for leafy spurge control. The objectives were 1) determine the return on investment of the cooperative, 2) determine the proposed structure of the cooperative, and 3) ascertain the amount of capital investment required by members in the cooperative. Three sheep flock management alternatives were initially considered for the cooperative. These were 1) winter lambing, 2) spring lambing, and 3) fall lambing. The fall lambing scenario was determined to be infeasible because of logistics associated with gathering and transportation of pregnant ewes and lack of grazing pressure on leafy spurge throughout the grazing season. The total capital investment per ewe for the winter lambing scenario was more than the spring lambing scenario - - 216, respectively. The expected net income generated by the winter lambing scenario was negative. The minimum break-even lamb selling price or lambs sold per ewe for the winter lambing scenario was 124,000 annually. The minimum breakeven lamb selling price or lambs sold per ewe for the spring lambing scenario was $59.51/cwt and 0.94, respectively. The expected return on investment (50% equity) for cooperative members with the spring lambing scenario, assuming a 50-acre leafy spurge infestation in a 100-acre pasture and new fence, was 16 percent (stocking rate of 1 ewe and lambs per acre of leafy spurge). While these returns are not a guarantee of success for the spring lambing alternative, they do provide an indication of the potential that such a cooperative may have.Leafy Spurge, Cooperative, Weed Control, Sheep Grazing, Economics, Farm Management, Resource /Energy Economics and Policy, Agribusiness,
LANDSAT menhaden and thread herring resources investigation
The author has identified the following significant results. The relationship between the distribution of menhaden and selected oceanographic parameters (water color, turbidity, and possibly chlorophyll concentrations) was established. Similar relationships for thread herring were not established nor were relationships relating to the abundance of either species. Use of aircraft and LANDSAT remote sensing instruments to measure or infer a set of basic oceanographic parameters was evaluated. Parameters which could be accurately inferred included surface water temperature, salinity, and color. Water turbidity (Secchi disk) was evaluated as marginally inferrable from the LANDSAT MSS data and chlorophyll-a concentrations as less than marginal. These evaluations considered the parameters only as experienced in the two test areas using available sensors and statistical techniques
Optical interferometer in space
The present design concepts for a Laser Gravitational Wave Observatory in Space are described. Laser heterodyne distance measurements are made between test masses located in three spacecraft separated by roughly 10(exp 6) km. The major technology issues are: the reduction of spurious acceleration noise for the test masses to below 2 x 10(exp -15) cm/sq sec/Hz(0.5) from 10(exp -5) to 10(exp -3) Hz; and the measurement of changes in the difference of the antenna arm lengths to 5 x 10(exp -11) cm/Hz(0.5) from 10(exp -3) to 1 Hz with high reliability. The science objectives are: to measure discrete sinusoidal gravitational wave signals from individual sources with periods of 1 second to 1 day; to measure the stochastic background due to unresolved binaries; and to search for gravitational wave pulses with periods longer than 1 sec from possible exotic sources such as gravitational collapse of very massive objects
Ribose supplementation alone or with elevated creatine does not preserve high energy nucleotides or cardiac function in the failing mouse heart
Background: Reduced levels of creatine and total adenine nucleotides (sum of ATP, ADP and AMP) are hallmarks of chronic
heart failure and restoring these pools is predicted to be beneficial by maintaining the diseased heart in a more favourable
energy state. Ribose supplementation is thought to support both salvage and re-synthesis of adenine nucleotides by
bypassing the rate-limiting step. We therefore tested whether ribose would be beneficial in chronic heart failure in control
mice and in mice with elevated myocardial creatine due to overexpression of the creatine transporter (CrT-OE).
Methods and Results: Four groups were studied: sham; myocardial infarction (MI); MI+ribose; MI+CrT-OE+ribose. In a pilot
study, ribose given in drinking water was bioavailable, resulting in a two-fold increase in myocardial ribose-5-phosphate
levels. However, 8 weeks post-surgery, total adenine nucleotide (TAN) pool was decreased to a similar amount (8–14%) in all
infarcted groups irrespective of the treatment received. All infarcted groups also presented with a similar and substantial
degree of left ventricular (LV) dysfunction (3-fold reduction in ejection fraction) and LV hypertrophy (32–47% increased
mass). Ejection fraction closely correlated with infarct size independently of treatment (r2 = 0.63, p<0.0001), but did not
correlate with myocardial creatine or TAN levels.
Conclusion: Elevating myocardial ribose and creatine levels failed to maintain TAN pool or improve post-infarction LV
remodeling and function. This suggests that ribose is not rate-limiting for purine nucleotide biosynthesis in the chronically
failing mouse heart and that alternative strategies to preserve TAN pool should be investigated
A PRELIMINARY FEASIBILITY FOR ESTABLISHING A MULTI-SPECIES MEAT PROCESSING PLANT IN SOUTHWESTERN NORTH DAKOTA
The number of small commodity livestock slaughter plants in the Upper Northern Plains region continues to decline. Significant factors contributing to this decline include: 1) pressure to consolidate, thereby capturing economies of scale; 2) relatively stringent federal inspection specifications, along with; 3) HACCP (Hazardous Analysis Critical Control Points) requirements. At the same time, consumer demand (markets) for specialty, selected, and exotic meats appears to be growing. For example, the recent market successes in Europe evidenced by the North American Bison Cooperative based in New Rockford, North Dakota. Several alternative livestock producer groups have emerged which include lamb, ratite, elk, deer, goat, poultry, rabbit, specialty beef, and organic livestock. These groups have expressed a need for slaughter and processing facilities to meet market demand. The economic question which then becomes foremost to developing a viable business enterprise is: "What is the critical threshold volume (CTV) of product required to succeed in terms of economic profit?" Specialty livestock is relatively new and production volume small in comparison to established commodity livestock such as cattle or hogs. This fact led researchers to consider the preliminary feasibility of a multi-species processing facility as a means of addressing the expressed need.multi-species, specialty meats, specialty livestock, alternative livestock, economies of scale, HACCP (Hazardous Analysis Critical Control Points), slaughter plants, processing plants, Community/Rural/Urban Development, Agribusiness,
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