Use of chromatographic pre-concentration for routine uranium bioassay analysis by ICP-MS

Routine monitoring of urine is an effective way to detect occupational intake of radioactive material. Historically, determinations of uranium isotopic ratios have been performed by radiochemical separation followed by alpha spectrometry. With recent advancements in technology, inductively coupled plasma-mass spectrometry (ICP-MS) has become widely available for the determination of trace metals as well as radioactive nuclides with long half-lives, such as ²³⁸U in urine. Furthermore, ICP-MS measurements of ²³⁸U do not require radiochemical separation since the number of atoms in the sample is determined instead of the number of alpha particles emitted. However, this method does not provide good sensitivity for the determination of ²³⁵U due to its shorter half-life. An improved procedure using pre-concentration of uranium and determination by ICP-MS decreases the detection limit by a factor of ten or greater with only slight increase in total analysis time. The method also has the capability of accurately determining the isotopic ratio of the sample, which is very important in cases where enriched or depleted uranium is involved.     

Differential inhibition of postnatal brain,spinal cord and body growth by a growth hormone antagonist

Background  

Growth hormone (GH) plays an incompletely understood role in the development of the central nervous system (CNS). In this study, we use transgenic mice expressing a growth hormone antagonist (GHA) to explore the role of GH in regulating postnatal brain, spinal cord and body growth into adulthood. The GHA transgene encodes a protein that inhibits the binding of GH to its receptor, specifically antagonizing the trophic effects of endogenous GH.     

Fusion around the barrier for 7Li+12C

Fusion cross-sections for the ⁷Li + ¹²C reaction have been measured at energies above the Coulomb barrier by the direct detection of evaporation residues. The heavy evaporation residues with energies below 3 MeV could not be separated out from the α-particles in the spectrum and hence their contribution was estimated using statistical model calculations. The present work indicates that suppression of fusion cross-sections due to the breakup of ⁷Li may not be significant for ⁷Li + ¹²C reaction at energies around the barrier.     

Automorphism groups of free geometries revisited

The number of types of free constructions introduced into geometry has increased steadily since the birth (2) of the free projective planes in 1943. The present paper is a follow up of (3) which introduces free geometries in terms ofsimple extensions. This point of view embeds a family of such constructions, here called the freelocally affine planes, into the discipline ofpartial order with noticeable technical simplifications as a consequence.Dedicated to Professor Helmut Mäurer on the occasion of his sixtieth birthday     

Radionuclides in produced water from Norwegian oil and gas installations — concentrations and bioavailability

Substantial amounts of produced water, containing elevated levels of radionuclides (mainly ²²⁶Ra and ²²⁸Ra) are discharged to the sea as a result of oil and gas production on the Norwegian Continental Shelf. So far no study has assessed the potential radiological effects on marine biota in connection with radionuclide discharges to the North Sea. The main objective of the project is to establish radiological safe discharge limits for radium, lead and polonium associated with other components in produced water from oil and gas installations on the Norwegian continental shelf.This study reports results indicating that the presence of added chemicals such as scale inhibitors in produced water has a marked influence on the formation of radium and barium sulphates when produced water is mixed with sea water. Thus, the mobility and bioavailability of radium (and barium) will be larger than anticipated. Also, the bioavailability of food-borne radium is shown to increase due to presence of such chemicals.     

Improving access to and utilization of genetic services in Arizona's Hispanic population

This abstract presents a model project aimed to train community lay health workers about genetics, increase cultural competency of genetic services providers, and provide local access to genetic services in primarily Hispanic communities in the state of Arizona. Health Start, a community-based prenatal outreach program, served as the basis for providing genetic education and services. A genetics training curriculum was developed and training of community lay health workers was provided. Cultural and Spanish language training was provided for all genetic services providers. Pediatric genetics outreach clinics were established in eight communities. Community-based lay health workers eagerly incorporate genetic information into their public health knowledge base, but this may not lead to acceptance of these personnel by local health care providers as sources of referrals for specialized health services such as genetics. Cultural competence training of genetic service providers is enthusiastically accepted and utilized in the provision of locally accessible genetics clinics.