Why Do We Let Our Soil Erode?

This is the third report on the progress being made in erosion control in western Iowa. Soil losses have been reduced, but they still exceed levels that operators themselves believe necessary to maintain soil productivity

Soil erosion control in western Iowa: progress and problems

The study on which this analysis is based was concerned with the socio-economic factors that prevented erosion control in western Iowa from coinciding with goals of erosion-control programs. Information was obtained by personal interview from 138 farm operators and 49 nonoperating owners of farms in the area in 1957 in a continuing investigation of the obstacles preventing adoption of erosion-control practices and of possible remedies for these obstacles. The same sample of farms had been included in two previous studies in 1949 and 1952. Data from these three studies were used to analyze the effects of changes in obstacles to erosion control on changes in soil loss. The average estimated annual soil loss for the sample decreased from 21.1 to 14.1 tons per acre from 1949-57. In an effort to determine why the 5- ton-per-acre goal of public programs in the area had not been attained in 1957, multiple variable linear regression was used to analyze the relationships between obstacles, farm characteristics and soil losses. The statistically significant obstacles preventing the reduction of soil losses by farm operators were (1) operators\u27 need for immediate income, (2) their failure to see the need for recommended practices (custom and inertia) and (3) field and road layout of the farms. Characteristics which explained a significant amount of variation in the estimated soil loss were (1) topography of the farm, (2) soil conservation district participation, (3) the operator\u27s ability to borrow funds for erosion-control practices, (4) days of off-farm work and (5) recognition of the seriousness of the erosioncontr01 problem by farm operators. While not statistically significant, the most important obstacles for nonoperating landowners were (1) need for immediate income and (2) insufficient roughage-consuming livestock on tenant-operated farms

Experimental investigation of optical atom traps with a frequency jump

We study the evolution of a trapped atomic cloud subject to a trapping frequency jump for two cases: stationary and moving center of mass. In the first case, the frequency jump initiates oscillations in the cloud's momentum and size. At certain times we find the temperature is significantly reduced. When the oscillation amplitude becomes large enough, local density increases induced by the anharmonicity of the trapping potential are observed. In the second case, the oscillations are coupled to the center of mass motion through the anharmonicity of the potential. This induces oscillations with even larger amplitudes, enhancing the temperature reduction effects and leading to nonisotropic expansion rates while expanding freely.Comment: 8 figures, Journal of Physics B: At. Mol. Op. Phy

Soil erosion and some means for its control

The control of soil erosion on the many farms where it is still a problem would not be difficult if it required only an understanding of the critical physical relationships between climate, topography, plant cover, water and soil as well as an ability to prescribe the proper engineering and agronomic measures for each situation. Soil losses, when greatly in excess of those produced by natural geological processes, result from the use of particular farming practices and cropping systems. While an understanding of the physical conditions which produce this erosion is essential, so is an understanding of the reasons that farmers choose the methods of farming which expose their soil to the hazard of heavy erosion losses.https://lib.dr.iastate.edu/specialreports/1027/thumbnail.jp

Inpatient glycemic variability and long-term mortality in hospitalized patients with type 2 diabetes

Aims/Hypothesis: To determine the association between inpatient glycemic variability and long-term mortality in patients with type 2 diabetes mellitus. Methods: Capillary blood glucose (CBG) of inpatients from 8 hospitals was analysed. 28,353 admissions identified were matched for age, duration of diabetes and admission and median and interquartile range of CBG. 6 year mortality was investigated for (i) those with CBG IQR in the top half of all IQR measurements (matched for all except IQR), vs those in the lower half and (ii) those with the lowest quartile median glucose (matched for all except median). Results: 1. Glycemic variability 3165 matched pairs were analysed. Mortality was greater in those with IQR in upper 50% (≥ 50.9 mg/dl) over follow-up from day 90 post-discharge to a maximum of 6 years (p<0.01, HR 1.17). 2. Median glucose 2.3755 matched pairs were analysed. Mortality was lower in those with a median glucose in upper 50% (≥ 148.5 mg/dl) over follow-up from day 90 post-discharge to a maximum of 6 years (p < 0.01, HR 0.87). Conclusion: Higher inpatient glycemic variability is associated with increased mortality on long-term follow up. When matched by IQR, we have demonstrated higher median CBG is associated with lower long-term mortality. CBG variability may increase cardiovascular morbidity by increasing exposure to hypoglycaemia or to variability per se. In hospitalized patients with diabetes, glycemic variability should be minimised and when greater CBG variability is unavoidable, a less stringent CBG target considered

Subpoena, Marshall County, M.S, 2 December 1837

https://egrove.olemiss.edu/aldrichcorr_a/1081/thumbnail.jp

Using the organ to teach the fourth suite prelude for violoncello solo by J.S. Bach

Among the Bach unaccompanied suites for violoncello, the fourth suite in E-flat major is probably the least familiar to listeners and young cellists. It is also the least idiomatic for the cello, and the most difficult movement is the prelude. Musically speaking, it can be frustratingly abstract. For these reasons, it is not as popular as the other preludes and some students and teachers avoid its study. Taking into account Bach's famous and primary skill as an organist, the cello idiom can be enhanced by studying the organ idiom and using this knowledge to study this prelude. Watching organists perform the music of Bach and listening to more of Bach's organ works, especially the praeludia, toccatas, and fantasias can give cellists ideas for this fourth suite prelude. An organ performance of a transcription of this fourth suite prelude will be available online in the near future as a resource for cellists interested in this relationship between the cello and organ idioms where genres like the prelude are concerned. Discussing the timbres and technical issues of the organ can guide the cellist toward ideas of phrasing and articulation. Organ issues of registration, manual changes, and performance style can aid the performer, teacher, and student in large-scale analysis and phrasing, thus making this prelude more accessible and shedding a more positive musical light upon this movement to make it less intimidating and abstract

Heliophysics Event Knowledgebase for the Solar Dynamics Observatory and Beyond

The immense volume of data generated by the suite of instruments on SDO requires new tools for efficient identifying and accessing data that is most relevant to research investigations. We have developed the Heliophysics Events Knowledgebase (HEK) to fill this need. The HEK system combines automated data mining using feature-detection methods and high-performance visualization systems for data markup. In addition, web services and clients are provided for searching the resulting metadata, reviewing results, and efficiently accessing the data. We review these components and present examples of their use with SDO data.Comment: 17 pages, 4 figure