The Illinois Soil N Test: Should it be used in Iowa?

What is the Illinois Soil N Test (ISNT)? The test was developed several years ago at the University of Illinois by researchers in the Department of Natural Resources and Environmental Sciences. It is a laboratory procedure designed to measure N liberated from soil heated for 5 hours with dilute alkali solution (sodium hydroxide). The test does not measure nitrate, but does measure exchangeable ammonium and a fraction of soil organic N. The theory behind the test is to extract a specific component of organic N from soil collected before planting and N application that can reflect the amount of N mineralized in a growing season to plant-available N forms (converted to inorganic ammonium and nitrate). The concept of estimating mineralized soil organic N is not new, as many biological and chemical methods have been proposed for the past 50 years. At best some of those tests predict available soil N in closed systems, such as in pots under greenhouse conditions, and none have been proved useful in predicting plant-available N in open systems such as field conditions. Unfortunately, it is extremely difficult to predict mineralization that might occur in the field with a lab test. This is the reason there has not been a reliable test developed or recommended to date

Investigation of Reclamation Procedure for Saline and Alkali Soils in Oklahoma

Soil

Three dimensional wave propagation in axially loaded pressurized FG cylindrical shells using Frobenius power series and Rayleigh-Ritz methods

In the present study, the behavior of vibratory cylindrical shells composed of functionally graded material (FGM) containing copper and tungsten under internal pressure and axial compression loads is investigated. An exact solution of free harmonic wave propagation using the theory of three dimensional elasticity is extracted. Then, the dispersion equation is analyzed in conjunction with a Frobenius power series method and natural frequency (eigenvalue) of the shell is obtained using Rayleigh-Ritz method. Furthermore, the present analysis is validated by comparing results with those available in the literature

Intracerebral atypical calcification in nongalenic pial arteriovenous fistula: a case report

Nongalenic intradural arteriovenous fistulas, although uncommon, are clinically important. Choosing the appropriate therapeutic approach has been a controversial issue within the last decade

Effect of Offloading Plantar Pressure on Peak Pressure in Ten Plantar Regions and Gait Speed in Men With Diabetes and Active Diabetic Foot Ulcers, and Healthy Men

Background and Aims Diabetes is associated with dysfunction and damage in various organs due to abnormal pressure on ten plantar regions. This study aims to compare the effect of offloading plantar pressure on peak pressure of ten plantar regions and gait speed in men with diabetes and active diabetic foot ulcers, and healthy men.Methods This is a causal-comparative study. Participants were 30 healthy men, 30 diabetic men and 30 men with active diabetic foot ulcers who needed no leg amputation according to their physicians. Sampling was done using random and convenience methods. Diabetic foot ulcers were classified based on the Meggitt-Wagner classification criteria, according to which grade 1 indicates grade 1 indicates a superficial ulcer and was used as a criterion for selecting people with diabetic foot ulcers. Plantar pressure variables were recorded using RSscan software (RSscan International, Belgium; 0.5×0.5×0.02 m, 4363 sensors) at a sampling frequency of 300 Hz and the gait speed was measured using a digital stopwatch. Correct walking considered as the full impact of the foot on the middle of the foot scan machine. Data were analyzed using independent t-test in SPSS software, version 24.Results The peak pressure in the metatarsal 3 (P<0.001), metatarsal 4 (P= 0.020), medial heel (P= 0.004) and lateral heel (P= 0.007) in the diabetic foot ulcer group significantly increased compared to the diabetic group. In addition, the peak pressure in the medial heel (P= 0.013) and lateral heel (P= 0.019) in the diabetic group significantly decreased compared to the healthy group.Conclusion Men with diabetic foot ulcers are more exposed to abnormal peak pressures in different plantar regions, which can cause irreversible clinical injuries. Diabetic men have a lower gait speed than healthy men which can be important in their rehabilitation