The estimation of individual doses for radiation protection and for risk assessment puposes from a radioiodine intake requires
a knowledge of the distribution and retention of the radioiodine (primarily in the thyroid), and a knowledge of the average
energy deposited in each organ of interest per radioactive decay (S-factors). This paper reviews a model for distribution
and retention used previously for adults, and extends the model to include all ages. The extended model also includes the
effects of stable iodine intakes on radioiodine uptakes explicity. Included in the paper is a tabulation of existing adult
S-factors for selected radioiodines and the extension of S-factors for the thyroid to all age groups. Finally, doses per unit
intake are calculated and tabulated. A discussion and some calculations of the effects of stable iodine intake on committed
doses are given.
The fluorine contents of plastics, ranging from about 20 μg·g−1 to 66%, may be measured instrumentally using a conventional research nuclear reactor, an automated sample irradiation and
counting system, and a set of well-calibrated, in-house, fluorine standards. Plastics with low to medium fluorine contents
may be analyzed using 20F by placing the gamma-ray detector at appropriate distances from the irradiated sample. For high-F plastics, samples may
be irradiated in a cadmium lined irradiation site, using 19O and 20F. Counting statistics of <3% translate into reproducibility of measurements within ±3% and analytical accuracies of ±1% to
Authors:E. Westrum, B. Justice, J. Sommers and D. Johnson
This paper is concerned with the estimation of heat capacities in the IVA 3d-transition element compounds using especially Zr and Hf compounds as examples. Most prediction schemes routinely tacitly assume that volumes and masses trend in parallel. However, the lanthanide contraction here ensures for ZrX/HfX systems — and generally elsewhere — that this is not so in this portion of the periodic table. Available methods such as Latimer's, Volumetric Priority, Komada-Westrum, Grimvall's, and Sommers' are compared on IVA elements and compounds. Only the Sommers approach has volumetric input. It provides the best prediction.
Authors:I. Johnson, R. Ramjegathesh, J. Sheela, N. Shoba and H. P. Maheshwarappa
The leaf blight disease caused by Lasiodiplodia theobromae is an important foliar disease in coconut that results in a yield reduction of 10–24 per cent in Tamil Nadu, India. In the present study, five Trichoderma viride isolates, Pseudomonas fluorescens and Bacillus subtilis strains were isolated from the coconut rhizosphere and tested against L. theobromae. P. fluorescens Pf1, B. subtilis (Km1) and T. viride (TNAU) isolates were found highly effective against the leaf blight pathogen under in vitro conditions and hence, all the three antagonists were combined together to develop microbial consortia and tested against leaf blight disease under field conditions. Soil application of microbial consortia formulated using talc as a carrier material at 150 g (50 g each) and 300 g (100 g each) doses at different intervals (quarterly, half-yearly and annually) was evaluated for three years from 2011 to 2013. Among the treatments, the fungicide carbendazim was found to be the most effective against coconut leaf blight. Among the treatments with bioagents, soil application of microbial consortia @ 300 g+5 kg of farm yard manure at quarterly interval/palm/year was the best treatment which was followed by the treatment with TNAU Bacillus subtilis (Bs1) mixture in two locations. Confirmatory results were obtained in similar experiments carried out at two different locations during 2013–2014, too.
Authors:Martina Uvacsek, Zs. Kneffel, M. Tóth, A.W. Johnson, P. Vehrs, J.W. Myrer and R. Hager
Cardiovascular disease (CVD) is responsible for more than half of all deaths in the European region. The aim of the study was to compare body composition, blood pressure, total cholesterol (TC) and high density lipoprotein cholesterol (HDL-C), family history, activity behaviors, and the 10-year risk of having a heart attack between 166 university students (21.62 ± 2.59 yrs) from Utah (USA) and 198 students (22.11 ± 2.51 yrs) from Hungary. Ninety-two percent of the Hungarian students and 100% of the Utah students had an estimated 10-year Framingham risk score of 1% or less. The high prevalence of low risk was primarily due to the young age of study participants, healthy body composition and non-smoking behavior. Hungarians who had higher 10-year risk of heart attack had significantly higher waist hip ratio (WHR), TC, diastolic blood pressure (DBP) and were smokers compared to those Hungarians with lower risk. The self-reported physical activity levels between the two groups of students were not different. In conclusion the young men and women who participated in this study were, for the most part healthy; however the smoking habits and the lower physical activity of the Hungarian students likely elevated their risk of CVD.
Authors:J. Schwantes, R. Addleman, J. Davidson, M. Douglas, D. Meier, O. Mullen, M. Myjak, M. Jones, M. Woodring, B. Johnson and P. Santschi
We are developing a medium-resolution autonomous in situ gamma detection system for marine and coastal waters. The system
is designed to extract and preconcentrate isotopes of interest from natural waters prior to detection in order to eliminate
signal attenuation of the gamma rays traveling through water and lower the overall background from the presence of naturally
occurring radioactive isotopes (40K and U–Th series radionuclides). Filtration is used to preconcentrate target isotopes residing on suspended particles, while
chemosorption is employed to preferentially extract truly dissolved components from the water column. Used filter and chemosorbent
media will be counted autonomously using two LaBr3 detectors in a near 4-π configuration around the samples. A compact digital pulse processing system, developed in-house and
capable of running in coincidence mode, is used to process the signal from the detectors to a small on-board computer. The
entire system is extremely compact (9″ dia. × 30″ len.) and platform independent, but designed for initial deployment on a
research buoy. A variety of commercial and in-house nano-porous chemosorbents have been selected, procured or produced, and
these and filter and detector components have been tested.