Probabilistic assessment of the impact of bottom sediment on doses to humans from a groundwater-mediated radionuclide release in a farm-lake scenario.

Radionuclide transport with groundwater flow and subsequent doses to people are an aspect to be studied when assessing the long-term safety of geological nuclear waste repositories. A scenario where the radionuclide release migrates through a three-layer sediment structure of a lake in a farming environment is presented in this paper. The sediment column consists of deep (till), intermediate (glacio-aquatic sediment) and top layers (clay). The radionuclide release is assumed to enter the deep sediment layer from a bedrock fracture system at a rate of 1 Bq yr-1. The main objectives of the paper are to investigate the most contributing parameters, especially linked to the sediment layers, to the overall dose estimates for humans. The sensitivity analysis was conducted in two phases where the Morris method was used for screening and the Extended Fourier Amplitude Sensitivity Testing and Sobol's methods were used for estimating total-order indices. The studied radionuclides, 36Cl, 135Cs, 129I, 94Nb, 237Np, 90Sr, 99Tc and 238U, exhibit differences in how the sediment layers affect the concentration in the lake water used for drinking, irrigation and watering cattle and subsequently the dose conversion factors for humans through ingestion, inhalation and external radiation.

Self-esteem in children in joint physical custody and other living arrangements.

OBJECTIVES: Parental support has been shown to be important for children's self-esteem, which in turn is related to later important life outcomes. Today, an increasing number of children in the Western world spend time in both the parents' respective households after a separation. Children who live with both parents report more parental support than children who live only with one parent after a divorce. We took the opportunity of the commonness of children sharing their time between their parents' homes in Sweden to investigate children's self-esteem in relation to family type. STUDY DESIGN AND METHODS: With nationally representative survey data (ULF) collected from both parents and children, we analyze differences in children's self-esteem among 4823 10-18 year olds in nuclear families, joint physical custody and those living mostly or only with one parent after a separation using ordinary least squares regression, adjusting for demographic and socioeconomic characteristics. RESULTS: We found no significant difference in self-esteem between children who lived equally much with both parents, mostly with one parent and those in nuclear families, whereas children in single care showed lower self-esteem compared with children in the other living arrangements. The difference was not explained by socioeconomic factors. CONCLUSION: The self-esteem of children who share their time between their parent's respective homes after a separation does not deviate from that in their peers in nuclear families. Instead, those in single care reported lower self-esteem than those in the other living arrangements. These differences were not explained by socioeconomic factors. Longitudinal studies are needed to establish pre- and post-separation family characteristics that influence self-esteem and well-being in young people.

Conversion electron spectrometry of Pu isotopes with a silicon drift detector.

An electron spectrometry set-up was built at IRMM consisting of a vacuum chamber with a moveable source holder and windowless Peltier-cooled silicon drift detector (SDD). The SDD is well suited for measuring low-energy x rays and electrons emitted from thin radioactive sources with low self-absorption. The attainable energy resolution is better than 0.5keV for electrons of 30keV. It has been used to measure the conversion electron spectra of three plutonium isotopes, i.e. (238)Pu, (239)Pu, (240)Pu, as well as (241)Am (being a decay product of (241)Pu). The obtained mixed x-ray and electron spectra are compared with spectra obtained with a close-geometry set-up using another SDD in STUK and spectra measured with a Si(Li) detector at IRMM. The potential of conversion electron spectrometry for isotopic analysis of mixed plutonium samples is investigated. With respect to the (240)Pu/(239)Pu isotopic ratio, the conversion electron peaks of both isotopes are more clearly separated than their largely overlapping peaks in alpha spectra.

Production of pure samples of 131mXe and 135Xe.

Pure samples of (131m)Xe, (133m)Xe, (133)Xe and (135)Xe facilitate the calibration and testing of noble gas sampler stations and related laboratory instrumentation. We have earlier reported a Penning trap-based production method for pure (133m)Xe and (133)Xe samples. Here we complete the work by reporting the successful production of pure (131m)Xe and (135)Xe samples using the same technique. In addition, we present data on xenon release from graphite.

Comparison of gamma-ray coincidence and low-background gamma-ray singles spectrometry.

Aerosol samples have been studied under different background conditions using gamma-ray coincidence and low-background gamma-ray singles spectrometric techniques with High-Purity Germanium detectors. Conventional low-background gamma-ray singles counting is a competitive technique when compared to the gamma-gamma coincidence approach in elevated background conditions. However, measurement of gamma-gamma coincidences can clearly make the identification of different nuclides more reliable and efficient than using singles spectrometry alone. The optimum solution would be a low-background counting station capable of both singles and gamma-gamma coincidence spectrometry.

Towards athermal organic-inorganic guided mode resonance filters.

We demonstrate guided-mode resonance filters featuring an amorphous TiO(2) layer fabricated by atomic layer deposition on a polymeric substrate. The thermal properties of such filters are studied in detail by taking into account both thermal expansion of the structure and thermo-optic coefficients of the materials. We show both theoretically and experimentally that these two effects partially compensate for each other, leading to nearly athermal devices. The wavelength shift of the resonance reflectance peak (< 1 nm) is a small fraction of the peak width (~11 nm) up to temperatures exceeding the room temperature by tens of degrees centigrade.

Energy loss measurement of protons in liquid water.

The proton stopping power of liquid water was, for the first time, measured in the energy range 4.7-15.2 MeV. The proton energies were determined by the time-of-flight transmission technique with the microchannel plate detectors, which were especially developed for timing applications. The results are compared to the literature values (from ICRU Report 49 (1993) and Janni's tabulation (1982 At. Data Nucl. Data Tables 27 147-339)) which are based on Bethe's formula and an agreement is found within the experimental uncertainty of 4.6%. Thus, earlier reported discrepancy between the experimental and literature stopping power values at lower energies was not observed at the energies considered in this experiment.

Ultra-high resolution mass separator--application to detection of nuclear weapons tests.

A Penning trap-based purification process having a resolution of about 1 ppm is reported. In this context, we present for the first time a production method for the most complicated and crucially important nuclear weapons test signature, (133m)Xe. These pure xenon samples are required by the Comprehensive Nuclear-Test-Ban Treaty Organization to standardize and calibrate the worldwide network of xenon detectors.

Generating hypergeometric laser beams with a diffractive optical element.

We derive explicit analytical relations to describe paraxial light beams that represent a particular case of the hypergeometric (HyG) laser beams [J. Opt. Soc. Am. A25, 262-270 (2008)JOAOD60740-323210.1364/JOSAA.25.000262]. Among these are modified quadratic Bessel-Gaussian beams, hollow Gaussian optical vortices, modified elegant Laguerre-Gaussian beams, and gamma-HyG beams. Using e-beam microlithography, a binary diffractive optical element capable of producing near-HyG beams is synthesized. Theory and experiment are in sufficient agreement. We experimentally demonstrate the ability to rotate dielectric microparticles using the bright diffraction ring of a HyG beam.

The decay of 133mXe.

The decay of (133m)Xe has been re-measured using an electron-transporter spectrometer and a planar HPGe detector. The sample of (133m)Xe was produced by means of proton-induced fission using an ion-guide based on-line mass separator. The deduced K and L+M+... shell conversion coefficients, alpha(Kappa)=6.5(9) and alpha(L+M+...)=2.9(4), agree within the uncertainty limits with the theoretical values and remove the inconsistencies between the previous experimental studies of (133m)Xe.

Design and investigation of color separation diffraction gratings.

Color separation gratings (CSGs) are designed within the framework of the rigorous electromagnetic theory using a gradient method. The optimality of the scalar-theory-based solutions is estimated. The results of the experimental study of a CSG to separate three wavelengths are presented.

Incorporating serotypes into family based association studies using the MFG test.

Family based association tests are widely used to detect genetic effects. The focus of this paper is the maternal-fetal genotype (MFG) incompatibility test, a family based association test which can be used to detect genetic effects that contribute to disease, including alleles in the child that increase disease risk, maternal alleles that increase disease risk in the child, and maternal-fetal genotype incompatibilities. Consideration of incomplete data resulting from using serotypes could expand the power of the MFG test for detecting genetic effects. Serotypes may be all that are available in certain families, or preferred because of convenience or low cost, and thus a modification of the MFG test will allow optimal use of such data. The modified MFG likelihood can accommodate the incomplete data that result from using serotypes rather than the corresponding codominant genotypes. The modified MFG test was evaluated with serotypes and genotypes from families with members affected with schizophrenia. In addition, simulation studies were performed. Results of the data analyses and simulation studies showed that serotypes can be used to augment genotypes within a sample, to increase power to detect effects when the candidate gene produces serotypes.

Diffraction of a plane, finite-radius wave by a spiral phase plate.

We derive analytical expressions containing a hypergeometric function to describe the Fresnel and Fraunhofer diffraction of a plane wave of circular and ringlike cross section by a spiral phase plate (SPP) of an arbitrary integer order. Experimental diffraction patterns generated by an SPP fabricated in resist through direct e-beam writing are in good agreement with the theoretical intensity distribution.

UV-absorbing compounds in subarctic herbarium bryophytes.

The UV-B-absorbing compounds of herbarium specimens of 10 subarctic bryophyte species collected during the years 1926-1996 and available at the Botanical Museum, University of Oulu, were studied. We studied whether herbarium specimens reflect changes in the past radiation climate through their methanol-extractable compounds. The order of gametophytes based on the average amount of total compounds (sum of A280-320 nm) per mass from the lowest to the highest was Polytrichum commune, Pleurozium schreberi, Hylocomium splendens, Sphagnum angustifolium, Dicranum scoparium, Funaria hygrometrica, Sphagnum fuscum, Sphagnum warnstorfii, Sphagnum capillifolium and Polytrichastrum alpinum, and the amount of UV-B-absorbing compounds per specific surface area correlated with the summertime daily global radiation and latitude. P. alpinum, F. hygrometrica and three Sphagnum species seem to be good indicators for further studies. The amount of UV-B-absorbing compounds revealed no significant trends from the 1920s till the 1990s, with the exception of S. capillifolium, which showed a significant decreasing trend.

Tenascin-C in primary malignant melanoma of the skin.

AIMS: To investigate the expression and the prognostic role of glycoprotein Tenascin-C (Tn-C) in primary melanoma of the skin. METHODS AND RESULTS: The immunohistochemical expression of Tn-C was studied in 98 primary melanomas and related to inflammation, invasion, and patient outcome. Patients were followed up for disease recurrence for 0.04-7.4 years (median 3.9) and for survival for 0.5 to 12.1 years (median 9.3). The expression of Tn-C was evaluated for each tumour invasion border; the stromal and intracytoplasmic Tn-C of the melanoma islets were also recorded. Tn-C is widely expressed in primary melanoma samples, the staining pattern varying from focal to diffuse in different parts of the tumour. No correlation existed between intensity of Tn-C staining and inflammation. No stromal Tn-C was detected at the upper dermal lateral border in 12 patients, nor at the deep, dermal or subcutaneous border in 14 patients. These patients showed better disease-free survival (DFS) than did those cases with focal or diffuse staining (P = 0.06, P = 0.05). Also, absence of intracytoplasmic Tn-C was a beneficial prognostic factor for DFS (P = 0.04). In multivariate analysis, tumour ulceration and intracytoplasmic Tn-C expression of melanoma cells were independent adverse prognostic factors for DFS. CONCLUSIONS: In primary melanoma of the skin, absence of Tn-C in the stroma of invasion fronts and within tumour cells seems to be related to a more benign disease behaviour with a lower risk of developing metastases.

Genome-wide scan in a nationwide study sample of schizophrenia families in Finland reveals susceptibility loci on chromosomes 2q and 5q.

We have previously carried out two genome-wide scans in samples of Finns ascertained for schizophrenia from national epidemiological registers. Here, we report data from a third genome scan in a nationwide Finnish schizophrenia study sample of 238 pedigrees with 591 affected individuals. Of the 238 pedigrees, 53 originated from a small internal isolate (IS) on the eastern border of Finland with a well established genealogical history and a small number of founders, who settled in the community 300 years ago. The total study sample of over 1200 individuals were genotyped, using 315 markers. In addition to the previously identified chromosome 1 locus, two new loci were identified on chromosomes 2q and 5q. The highest LOD scores were found in the IS families with marker D2S427 (Z(max) = 4.43) and in the families originating from the late settlement region with marker D5S414 (Z(max) = 3.56). In addition to 1q, 2q and 5q, some evidence for linkage emerged at 4q, 9q and Xp, the regions also suggested by our previous genome scans, whereas, in the nationwide study sample, the region at 7q failed to show further evidence of linkage. The chromosome 5q finding is of particular interest, since several other studies have also shown evidence for linkage in the vicinity of this locus.

Further evidence for linkage of autosomal-dominant medullary cystic kidney disease on chromosome 1q21.

BACKGROUND: Autosomal-dominant medullary cystic kidney disease (ADMCKD) is characterized by the development of cysts at the corticomedullary border of the kidneys. It resembles nephronophthisis (NPH) with an autosomal-recessive mode of inheritance. Genetic linkage has been shown either on chromosome 1q21 (ADMCKD1) or 16p12 (ADMCKD2), and families exist who are not linked to the aforementioned loci. No disease-causing gene underlying this disorder has been reported. METHODS: The Finnish Transplantation Register and hospital records were searched to identify all of the ADMCKD families in the Finnish population. Detailed clinical information of the patients was collected. Linkage analysis was used to study whether the Finnish families originating from a homogeneous population showed genetic linkage to the ADMCKD1 or ADMCKD2 loci. Also, the coding region of a strong candidate gene, natriuretic peptide receptor A (NPRA), located on the chromosome 1q21 critical region, was sequenced using polymerase chain reaction sequencing with an ABI 377XL Automated DNA sequencer (Applera Corp., Norwalk, CT, USA). RESULTS: Five of the six families showed linkage to the previously identified region of chromosome 1q21. Family 6 with hyperuricemia as a prominent clinical feature was linked to neither of the ADMCKD loci. Wide interfamiliar and intrafamiliar variability in the clinical picture of the patients was detected. The NPRA gene mutation was excluded as a causative gene by sequencing. CONCLUSION: This study locates the gene for ADMCKD1 close to a marker D1S1595 in a region <5 cM, and further confirms the existence of at least three loci for the medullary cystic kidney disease. Heterogeneity of the symptoms complicates the clinical diagnosis and classification of the patients. Further studies are needed to identify the disease-causing gene.

Effects of abrupt surface-profile transitions in nonparaxial diffractive optics.

It is shown that the failure of the thin-element approximation of diffractive optics may, in the first approximation, be attributed to local diffraction effects caused by the abrupt vertical transitions in binary surface-relief profiles. We determine the field disturbance caused by a single-step transition (of given height) by rigorous diffraction theory. Associating such a disturbance with each individual transition point in the profile, we obtain a computationally efficient refinement of the thin-element approximation for the analysis and design of diffractive elements in the nonparaxial domain. The results agree well with those obtained by global application of rigorous diffraction theory, provided that the smallest features in the binary profile are larger than approximately one optical wavelength.

Percutaneous transcatheter renal embolization with absolute ethanol for uncontrolled nephrotic syndrome. Case reports.

PURPOSE: To retrospectively evaluate renal ethanol embolization in 2 patients with uncontrolled nephrotic syndrome. MATERIAL AND METHODS: Three kidneys in 2 patients with uncontrolled nephrotic syndrome were embolized with absolute ethanol. The embolization technique, patient outcome and complications were analyzed retrospectively. RESULTS: The treatment was successful in both patients, with angiography-verified exclusion of blood flow to the renal arteries. Elimination of proteinuria was achieved in both patients and their body weight decreased by 25 and 10 kg, respectively. Hospitalization and protein substitution were no longer needed. No complications occurred. CONCLUSION: Permanent bilateral ethanol embolization of the renal arteries is a feasible method of managing a treatment-resistant nephrotic syndrome in selected patients. Non-target embolization can be avoided by using a balloon occlusion catheter.