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Abstract: In-situ gamma-ray spectrometry is widely used for monitoring of natural as well as man-made radionuclides and corresponding gamma fields in the environment or working places. It finds effective application in the operational and accidental monitoring of nuclear facilities and their vicinity, waste depositories, radioactive contamination measurements and environmental mapping or geological prospecting. In order to determine accurate radionuclide concentrations in these research fields, Monte Carlo codes have recently been used to obtain the efficiency calibration of in-situ gamma-ray detectors. This work presents an inter-comparison between two Monte Carlo codes applied to in-situ gamma-ray spectrometry. On the commercial market, Canberra has its LABSOCS/ISOCS software which is relatively inexpensive. The ISOCS mathematical efficiency calibration software uses a combination of Monte Carlo calculations and discrete ordinate attenuation computations. Efficiencies can be generated in a few minutes in the field and can be modified easily if needed. However, it has been reported in the literature that ISOCS computation method is accurate on average only within 5%, and additionally in order to use LABSOCS/ISOCS it is necessary a previous characterization of the detector by Canberra, which is an expensive process. On the other hand, the multipurpose and open source GEANT4 takes significant computer time and presents a non-friendly but powerful toolkit, independent of the manufacturer of the detector. Different experimental measurements of calibrated sources were performed with a Canberra portable HPGe detector and compared to the results obtained using both Monte Carlo codes. Furthermore, a variety of efficiency calibrations for different radioactive source distributions were calculated and tested, like plane shapes or containers filled with different materials such as soil, water, etc. LabSOCS simulated efficiencies for medium and high energies were given within an accuracy of below 5% for point sources and 10% maximum accuracy for more complicated geometries. Accuracy for LabSOCS decreased for low energy emissions. Finally an analysis and discussion of the results and the main differences found between LabSOCS and GEANT4 were performed. [Copyright &y& Elsevier]

A nondestructive method based on low-energy, high-resolution photon spectrometry is presented which allows accurate determination of 239Pu, 240Pu, and 241Am (as a daughter of 241Pu) activities in radioactive particles containing relatively high levels of plutonium isotopes. The proposed method requires only one measurement for the establishment of an absolute efficiency curve. Since the density and composition of the radioactive particles of interest may vary, a self-absorption correction is required for the accurate determination of isotopic activities and ratios. This correction is carried out for each individual particle using the convenient gamma-ray emissions of 241Am. [ABSTRACT FROM AUTHOR]

In this paper coincidence summing corrections in gamma-ray spectrometry have been analyzed in depth. Experimental setup included a n-type germanium detector and two efficient geometries of measurement (Marinelli beaker and air filter) calibrated with multi gamma radionuclides in the energy range of 40-1500 keV. Monte Carlo simulations were carried out using the GEANT4 code in order to develop this work. Firstly an optimization of the detector dimensions was performed to obtain the full-energy peak efficiency curve. Next, the simulation of the decay schemes for involved multi gamma radionuclides were appended to the GEANT4 code including beta, alpha, EC decay, together with the subsequent relaxation process consisting of a cascade of fluorescent X-rays and Auger electrons. In order to test the simulations an comparison between an experimental and a calculated spectra of 133Ba point source was carried out. Finally coincidence summing effects for gamma-ray emission and X-ray, Auger electron, beta and EC electron were studied in detail. [ABSTRACT FROM AUTHOR]

Abstract: In this work several mathematical functions are compared in order to perform the full-energy peak efficiency calibration of HPGe detectors using a HPGe coaxial detector and gamma-ray energies ranging from 36 to 1460keV. Statistical tests and Monte Carlo simulations were used to study the performance of the fitting curve equations. Furthermore the fitting procedure of these complex functional forms to experimental data is a non-linear multi-parameter minimization problem. In gamma-ray spectrometry usually non-linear least-squares fitting algorithms (Levenberg–Marquardt method) provide a fast convergence while minimizing , however, sometimes reaching only local minima. In order to overcome that shortcoming a hybrid algorithm based on simulated annealing (HSA) techniques is proposed. Additionally a new function is suggested that models the efficiency curve of germanium detectors in gamma-ray spectrometry. [Copyright &y& Elsevier]

Abstract: This work presents an intercomparison between commercial software for alpha-particle spectrometry, Genie 2000, and the new free available software, Winalpha, developed by International Atomic Energy Agency (IAEA). In order to compare both codes, different environmental spectra containing plutonium, uranium, thorium and polonium have been analyzed, together with IAEA test alpha spectra. A statistical study was performed in order to evaluate the precision and accuracy in the analyses, and to enhance the confidence in using the software on alpha spectrometric studies. [Copyright &y& Elsevier]

The solid state photodimerization of ethyl coumarin-3-carboxylate and its 6-Cl and 6-Br (1a-c) derivatives as well as the methyl and ethyl alcoholysis derivatives of ethyl coumarin-3-carboxylate photodimer are reported in the context of crystal engineering. Ethyl coumarin-3-carboxylates photodimerize topochemically to form anti head-to-tail stereoisomers (2a-c). The extent of lactone methanolysis of 2a depends on the boiling temperature of the solvent to produce 2-(2-hydroxyphenyl)-3-oxo-8bH-4-oxa-cyclobuta[a]naphthalene-1,1,2a-tricarboxylic acid 1,2a-diethyl ester 1-methyl ester (3a) and 2,4-bis-[(2-hydroxyphenyl]cyclobutane-1,1,3,3-tetracarboxylic acid diethyl ester dimethyl ester (4a) in 1:2 proportion, whereas the ethanolysis of 2a only yields 2-(2-hydroxyphenyl)-3-oxo-8bH-4-oxa-cyclobuta[a]naphthalene-1,1,2a-tricarboxylic acid triethyl ester (5a). The molecular structure of 2a-c and 3-5a were elucidated by 1H and 13C NMR spectroscopy. Also the molecular and supramolecular structures of 2a,b and 3,4a were studied by X-ray diffraction. Most of the C-H...X (X = O, Ph), π...π and dipolar interactions in the photodimers 2a,b and derivative 3a are preserved from the corresponding original coumarin monomers. Thus the supramolecular structure of ethyl coumarin-3-carboxylate is conserved through this group of compounds as if they would have a "supramolecular memory". [image omitted] [ABSTRACT FROM AUTHOR]

Abstract: An experimental procedure has been developed for a rapid and accurate determination of the activity concentration of 210Pb in sediments by liquid scintillation counting (LSC). Additionally, an alternative technique using -spectrometry and Monte Carlo simulation has been developed. A radiochemical procedure, based on radium and barium sulphates co-precipitation have been applied to isolate the Pb-isotopes. 210Pb activity measurements were done in a low background scintillation spectrometer Quantulus 1220. A calibration of the liquid scintillation spectrometer, including its / discrimination system, has been made, in order to minimize background and, additionally, some improvements are suggested for the calculation of the 210Pb activity concentration, taking into account that 210Pb counting efficiency cannot be accurately determined. Therefore, the use of an effective radiochemical yield, which can be empirically evaluated, is proposed. 210Pb activity concentration in riverbed sediments from an area affected by NORM wastes has been determined using both the proposed method. Results using -spectrometry and LSC are compared to the results obtained following indirect -spectrometry (210Po) method. [Copyright &y& Elsevier]

Abstract: This paper presents a self-sufficient and general method for measurement of the activity of low-level gamma-emitters in voluminous samples by gamma-ray spectrometry with a coaxial germanium detector. Due to self-absorption within the sample, the full-energy peak efficiency of low-energy emitters in semiconductor gamma-spectrometers depends strongly on a number of factors including sample composition, density, sample size and gamma-ray energy. As long as those commented factors are well characterized, the influence of self-absorption in the full-energy peak efficiency of low-energy emitters can be calculated using Monte Carlo method based on GEANT4 code for each individual sample. However this task is quite tedious and time consuming. In this paper, we propose an alternative method to determine this influence for voluminous samples of unknown composition. Our method combines both transmission measurements and Monte Carlo simulations, avoiding the application of Monte Carlo full-energy peak efficiency determinations for each individual sample. To test the accuracy and precision of the proposed method, we have calculated 210Pb activity in sediments samples from an estuary located in the vicinity of several phosphates factories with the proposed method, comparing the obtained results with the ones determined in the same samples using two alternative radiometric techniques. [Copyright &y& Elsevier]

This study proposes an empirically based model with a strong theoretical foundation in higher education and social psychology to better understand how the college experience influences the development of attitudes of acceptance towards lesbian, gay, and bisexual (LGB) persons. Our results demonstrated that students develop more accepting attitudes toward LGB persons when they enroll in diversity courses, interact across race, or interact with LGB peers. In addition, we found that students' thoughts about their identity in college as well as their comfort around LGB persons are important influences on LGB attitude development. [ABSTRACT FROM AUTHOR]

Abstract: The background of a coaxial Ge detector placed at a surface laboratory has been reduced by means of a background reduction setup consisting of a passive shield of low-activity lead, a simple radon suppression system and an active shield with a plastic scintillation plate. In particular, we have devoted our efforts to in-depth optimization of each parameter associated with different anticoincidence setups and to their subsequent intercomparison. The overall performance of the active shield was improved by using the optimum time parameters for each setup. The final objective is to decrease the cosmic-ray background and, by this way, to reduce the detection limits of gamma-ray spectrometers at conventional laboratories, and consequently make them competitive for different measurements like 210Pb dating. [Copyright &y& Elsevier]

The use of Web-based programs for a variety of health education, risk reduction, and health promotion purposes can be a valuable tool in the effort to improve the health of a population. Providing theory-based personalized feedback through such a method can be particularly useful in alcohol misuse prevention efforts. A brief alcohol use feedback program was developed for members of the U.S. Marine Corps, and user-satisfaction ratings were collected from 167 participants. Approximately 44% of the sample found the program to be useful or very useful, and 46% of the sample reported that they were likely or very likely to recommend the Web site to others. The Web-based format with tailored responses was preferred by 85% of respondents over other more traditional methods of alcohol training, and 80% of participants felt that the feedback was appropriate for Marines in their community. Significantly higher usefulness, likelihood of recommending the program to others, and overall ratings of the program were reported among younger and nonheavy-drinking participants (p < .05). Results indicate that this computerized assessment and feedback program is a promising mechanism with which to provide personalized alcohol misuse prevention information. [ABSTRACT FROM AUTHOR]

Abstract: The energy and resolution calibration of germanium detectors being basic procedures in gamma-ray spectrometry have not been usually studied in depth. In this paper a new approach to these calibration methods based on the Orthogonal Distance Regression (ODR) algorithm is presented. This algorithm treats more adequately all uncertainties involved in the calibration process and produces better results than the usual Ordinary Least Squares (OLS) algorithm. Additionally a study of the functions involved in energy and resolution calibration of germanium detectors has been also carried out. [Copyright &y& Elsevier]

Abstract: For a series of 3-substituted-thietane-1-oxide (3-R-TOX) derivatives (R=chloro, methyl, ethyl, acetate, t-buthyl, phenyl and p-chlorophenyl), the cis⇔trans isomerization reactions have been theoretically studied in the frame of molecular orbital theory. Optimized geometries have been obtained at HF/6-31G** level, whereas the energetics and thermodynamics were calculated with basis sets that include polarization, diffuse functions and electron correlation at the second-order Møller–Plesset perturbation theory. The size and nature of the substituent seems to exert no influence on the structure of the thietane-1-oxide ring. Gas phase thermodynamics predict the cis isomers to be the preferred structure in these compounds as a result of the H10⋯O9 non-bonded interaction. The exception to this trend are the chloro and acetate derivatives where a 14 and 46% of the trans isomer, respectively, is predicted. In CCl4 solution, the isomerization reaction would take place in large extent. The calculated 1H-NMR chemical shifts correlate well with the experimental data and demonstrate that the β-protons (H10) are magnetically sensible enough to allow the cis and trans isomeric forms to be distinguished. The β-protons chemical shifts calculated in CCl4 do not differ appreciably from the gas phase values. The 17O-NMR signals have also been derived and the potentiality of this nucleus to be used to assign the preferred geometry as well as to follow the isomerization reaction, in this kind of compounds is pointed out. The present work also indicates that the Sing mode can be used to assign either a cis or trans conformation in these species, though this vibrational mode is strongly coupled with some ring and H–C–H angle deformation modes. [Copyright &y& Elsevier]

In this paper, we will expose the work performed for the adaptation and refinement of the GEANT4 simulation toolkit (originally designed for Monte Carlo simulations in High-Energy Physics) in order to simulate Ge detectors in low-level gamma spectrometry. Special emphasis will be given to show and validate our own algorithms implemented in GEANT4 code for variance reduction and data analysis, that have been used for a quicker and precise efficiency calibration at different source-detector configurations of one of the low-level germanium gamma systems available in our laboratory. [Copyright &y& Elsevier]

The GEANT4 software was developed by RD44, a world-wide collaboration of national institutes, laboratories and large High-Energy Physics experiments. GEANT4 is a public software package composed of tools which can be used to accurately simulate the passage of particles through matter. In this article, the first attempt to use GEANT4 to model a reverse electrode germanium detector (REGe), and to improve also its efficiency calibration procedure, is presented. A variance reduction algorithm based on a directional bias scheme is implemented into GEANT4 in order to accelerate the efficiency computations. A fast optimisation method to model the detector geometry using standard point sources is also presented and validated for point, Marinelli and air filter sources. The simulated full-energy peak efficiencies agreed with the measured values to within 1% between 36 and 1460 keV for these three counting geometries. [Copyright &y& Elsevier]

: BackgroundHypertension (HT), a prevalent complication in renal transplant patient (RT), must be accurately treated because cardiovascular disease is the leading cause of death and of chronic graft dysfunction. Sympathetic activity may contribute to HT in RT, yielding the rationale to suspect that doxazosin, an α1-adrenergic receptor inhibitor, may lower blood pressure (BP). The aim of this study was to evaluate the efficacy and safety of doxazosin GITS (4 and 8 mg) in RT.: MethodsTwenty-three hypertensive RT received doxazosin 4 mg once daily for 4 weeks (W4) followed by a 4-week washout (W0) and 17/23 treated with doxazosin 8 mg for 4 more weeks (W8) due to persistent HT. All patients underwent 24-hour ambulatory blood pressure monitoring (ABPM) after W0, W4, and W8. Laboratory tests were performed, adverse events recorded, and prostatic symptomatology examined. Statistical analysis included Saphiro-Wilks, Student t, ANOVA, Wilcoxon, or Friedman tests.: ResultsThe systolic, diastolic, and mean BP were significantly lowered at W4 in awake (P < .001) and 24 hour period (P < .005) but not sleep recordings. Doxazosin 8 mg had no significant additional effect to lower BP at any period. Normotension was reached in 13% and 21.7% of patients at W4 and W8, respectively. Palpitations were the only reported adverse event after treatment (incidence similar to placebo). There was no significant change in the laboratory values.: ConclusionsDoxazosin (−4 mg) effectively decreased BP in awake and 24-hour periods without a significant improvement during sleep. A double dose of the drug added little benefit. Optimal BP was reached by an insufficient number of patients. Doxazosin proved to have a good tolerance and safe profile. This results suggest that doxazosin should be considered a good add-on treatment to other antihypertensive drugs in RT. [Copyright &y& Elsevier]

Summary As willow (Salix ) cultivation grows globally, worldwide monitoring of pathotypes for Melampsora rust, the most serious disease in willow, becomes increasingly important. We compared the pathotype composition of the Melampsora rust population in Chile with that in Sweden and assessed inocula exchange for the rust between the continents. For pathotyping rust isolates, a willow differential was used (a standardized set of willow test clones) to obtain clone-virulence patterns. These patterns were used to identify virulence components involved in determining which willow clones a given individual pathogen isolate (genotype) can successfully attack. Each virulence component detected earlier in Sweden's rust population was present in Chile's rust population. Using isoenzyme analysis to classify willow species in Chile, a low genetic variation of Salix viminalis (an introduced willow species) was found, compared with the endemic species Salix humboldtiana . Comparison of rust populations for the two countries supports the present hypothesis that intercontinental inocula exchange can be a significant determinant of local pathotype structure, and consequently can be important for willow-resistance breeding. [ABSTRACT FROM AUTHOR]

210Pb radioimpurities in different lead pieces used for shielding low-level gamma-ray spectrometers have been determined through the application of two independent radiometric techniques: alpha-particle spectrometry (210Po) and Cherenkov counting (210Bi). Associated to each technique, simple radiochemical procedures have been developed for the isolation of the radionuclides of interest and/or their adaption to the measurement conditions. These determinations are very useful in designing low-level gamma-spectrometric systems as well as in the interpretation, evaluation and even simulation of their background spectra. [Copyright &y& Elsevier]

Melampsora epitea , the causal agent of leaf rust on willow (Salix spp.) in short-rotation forestry, was sampled over four consecutive years (1993–96) in Sweden. The pathotype patterns of 332 single-spore isolates were examined for virulence characteristics using a defined set of willow hosts. Thirty-seven pathotypes of M. epitea were identified and grouped into three formae speciales . No race or morph subdivision was observed among the isolates, other than the three formae speciales . For monitoring and studying the ecological and evolutionary dynamics of virulence for M. epitea , an internationally useful naming system for pathotypes is proposed, with a three-digit code referring to virulence on a specified set of standard test clones. [ABSTRACT FROM AUTHOR]

Vitamins A, E, and those of the B complex were determined in 59 standard and 11 specialized infant milks from the Spanish market. Water-soluble vitamin levels were lower than those declared by manufacturers in 50% of the standard infant milk products. Vitamin A ranged from 58.8 µg/100mL to 170.9 µg/100mL and vitamin E from 0.8 mg/100mL to 3.3 mg/100ml. Most of the samples had a higher vitamin A content than that stated by the manufacturer, and 13% and 42% of them exceeded the Spanish legislation and the ESPGAN recommendation levels respectively. Vitamin E levels were between 2 and 10 times higher than the minimum established by these organizations and in general were over the declared level. [ABSTRACT FROM AUTHOR]

Two infant milks claimed to have the same final composition in liquid and powdered form respectively were stored for 12 mo at 20, 30, and 37 °C. Vitamin E, thiamin, riboflavin, pyridoxine, folic acid, and nicotinamide remained constant at the three temperatures. However, there were statistically significant losses of vitamin A (approximately 35%) in samples stored at 37 °C. No differences were observed in vitamin stability between the two infant milks studied. Final levels of vitamin A were always higher than the minimum set by Spanish legislation. Vitamin A overfortification (approximately 200%) was more than that needed to compensate for losses during storage. [ABSTRACT FROM AUTHOR]

One of the major constraints for studies on the sporogonic cycle of the parasites causing human malaria, and on the protective efficacy of pre-erythrocytic vaccines, is the scarcity of laboratory-reared Anopheles mosquitoes as a source of infective sporozoites. The aim of the present study was to reproduce the life-cycles of Plasmodium falciparum and P. vivax in the laboratory and so develop the ability to produce infective sporozoites of these two species regularly under laboratory conditions. Colonized Anopheles albimanus, of Buenaventura and Tecojate strains, were infected by feeding either on Plasmodium-infected blood, from human patients or experimentally inoculated Aotus monkeys, or on gametocytes of the P. falciparum NF-54 isolate grown in vitro. The monkeys were infected with the blood stages of a Colombian P. vivax isolate and then, after recovery, with the Santa Lucia strain of P. falciparum from El Salvador. Although both of the mosquito strains used were successfully infected with both parasite species, the Buenaventura strain of mosquito was generally more susceptible to infection than the Tecojate strain, and particularly to infection with the parasites from the patients, who lived where this strain of mosquitoes was originally isolated. Monkeys injected intravenously with the P. vivax sporozoites produced in the mosquitoes developed patent sexual and asexual parasitaemias; the gametocytes that developed could then be used to infect mosquitoes, allowing the development of more sporozoites. However, experimental infections failed to establish after the P. falciparum sporozoites were used to inoculate monkeys. The ability to reproduce the complete life cycle of P. vivax in the laboratory, from human to mosquito and then to monkey, should greatly facilitate many studies on vivax malaria and on the efficacy of candidate malaria vaccines. The availability of the sporogonic cycles of P. falciparum from three different sources should also permit a variety of biological studies. [ABSTRACT FROM AUTHOR]

The aim of this study was to check for equivalence of computer codes that are capable of performing calculations of true coincidence summing (TCS) correction factors. All calculations were performed for a set of well-defined detector parameters, sample parameters and decay scheme data. The studied geometry was a point source of 133 Ba positioned directly on the detector window of a low-energy (n-type) detector. Good agreement was established between the TCS correction factors computed by the different codes. [ABSTRACT FROM AUTHOR]

Industrial activities involving Naturally Occurring Radioactive Materials (NORM) are found among the most important industrial sectors worldwide as oil/gas facilities, metal production, phosphate Industry, zircon treatment, etc. being really significant the radioactive characterization of the materials involved in their production processes in order to assess the potential radiological risk for workers or natural environment. High resolution gamma spectrometry is a versatile non-destructive radiometric technique that makes simultaneous determination of several radionuclides possible with little sample preparation. However NORM samples cover a wide variety of densities and composition, as opposed to the standards used in gamma efficiency calibration, which are either water-based solutions or standard/reference sources of similar composition. For that reason self-absorption correction effects (especially in the low energy range) must be considered individually in every sample. In this work an experimental and a semi-empirical methodology of self-absorption correction were applied to NORM samples, and the obtained results compared critically, in order to establish the best practice in relation to the circumstances of an individual laboratory. This methodology was applied in samples coming from a TiO 2 factory (NORM industry) located in the south-west of Spain where activity concentration of several radionuclides from the Uranium and Thorium series through the production process was measured. These results will be shown in this work. [ABSTRACT FROM AUTHOR]

The goal of this study is to provide a benchmark for the use of Monte Carlo simulation when applied to coincidence summing corrections. The examples are based on simple geometries: two types of germanium detectors and four kinds of sources, to mimic eight typical measurement conditions. The coincidence corrective factors are computed for four radionuclides. The exercise input files and calculation results with practical recommendations are made available for new users on a dedicated webpage. • Examples of the use of Monte Carlo simulation to calculate coincidence summing corrections. • Simple cases with two types of germanium detectors and four kinds of sources were investigated. • Calculation of coincidence summing correction factors for 60Co, 134Cs, 133Ba and 22Na is presented. • Input files, correction factors and recommendations are available on a dedicated webpage. [ABSTRACT FROM AUTHOR]

Abstract: This work focuses on the monitoring of the potential pollution in scenarios that involve NORM-related industrial activities (environmental or in-door scenarios). The objective was to develop a method to determine extent and origin of the contamination, suitable for monitoring (i.e. simple, fast and economical) and avoiding the use of too many different instruments. It is presented a radiochemical method that allows the determination of trace element concentrations and 206Pb/207Pb/208Pb, 238U/234U and 232Th/230Th isotope ratios using a single sample aliquot and a single instrument (ICP-QMS). Eichrom UTEVA® extraction chromatography minicolumns were used to separate uranium and thorium in sample leachates. Independent ICP-MS determinations of uranium and thorium isotope ratios were carried out afterwards. Previously a small aliquot of the leachate was used for the determination of trace element concentrations and lead isotope ratios. Several radiochemical arrangements were tested to get maximum performances and simplicity of the method. The performances of the method were studied in terms of chemical yields of uranium and thorium and removal of the potentially interfering elements. The established method was applied to samples from a chemical industry and sediments collected in a NORM-polluted scenario. The results obtained from our method allowed us to infer not only the extent, but also the sources of the contamination in the area. [Copyright &y& Elsevier]

In this work a method used conventionally for ICP-MS measurements have been modified and readapted for the determination of actinides (U and Th isotopes) in refractory samples by alpha-spectrometry. The method is based in a total dissolution of the sample by alkali fusion. In the first stages of our studies, we try to digest refractory samples by leaching with aqua regia followed by the application of a liquid-liquid solvent extraction process for the sequential isolation of the uranium and thorium isotopes from the dissolved fraction. These actinides were finally electroplated in stainless steel discs and measured in an alpha-spectrometer using PIPS detectors. On the other hand, gamma measurements were carried out in aliquots of the same samples in order to check the results produced by alpha spectrometry. Clear disagreements were found between the results obtained by both techniques. This problem was solved by the application of an alkali fusion technique where a total dissolution of the sample is performed. It was found in addition that the alkali fusion is easily applicable, less time-consuming, needs less reagents than leaching and it does not require sophisticated apparatus to be executed. In this paper the whole procedure for U and Th determination in refractory samples by alpha-spectrometry with alkali fusion is presented and validated. [ABSTRACT FROM AUTHOR]

Abstract: The Huelva Estuary in Huelva, Spain, has been one of the most studied environmental compartments in the past years from the point of view of naturally occurring radioactive material (NORM) releases. It has been historically affected by waste releases, enriched in radionuclides from the U-decay series, from factories located in the area devoted to the production of phosphoric acid and phosphate fertilizers. Nevertheless, changes in national regulations forced a new waste management practice in 1998, prohibiting releases of phosphogypsum into the rivers. The input of natural radionuclides from phosphate factories to rivers was drastically reduced. Because of this there was a unique opportunity for the study of the response of a contaminated environmental compartment, specifically an estuary affected by tidal influences, after the cessation of the contaminant releases to, in this case, the Huelva Estuary (henceforth referred to as the Estuary). To investigate the environmental response to this new discharge regime, the specific activities of radionuclides 226Ra and 210Pb in water and sediment samples collected in four campaigns (from 1999 to 2005) were determined and compared with pre-1998 values. From this study it is possible to infer the most effective mechanisms of decontamination for the Estuary. Decontamination rates of 210Pb and 226Ra in the sediments and water have been calculated using exponential fittings and corresponding half-lives have been deduced from them. The cleaning half-life in the whole area of the Estuary is about 6 and 3.5years for 226Ra and 210Pb respectively. The observed trend clearly shows that contamination of the Estuary by natural radionuclides is now decreasing and radioactive levels in waters and sediments are approaching the natural background references. This work attempts to evaluate whether it can be expected that the decontamination of the enhanced levels of natural radioactivity in the Estuary can be performed via natural processes. [Copyright &y& Elsevier]

Background: Hypertension (HT) accounts for nearly 60% to 80% of renal transplant patients (RT). It is one of the most important risk factors for cardiovascular diseases and may cause chronic graft dysfunction. Therefore, it is important to accurately detect and treat HT. We aimed to evaluate the changes in ambulatory blood pressure monitoring (ABPM) parameters among hypertensive RT after active treatment compared with baseline values.Methods: Thirty seven RT (25 men, 12 women, aged 49.4 ± 11.2 year) diagnosed with mild to moderate HT underwent 24-hour ABPM after a 4-week washout period (W0). For the 23 RT with confirmed HT of a second 24-hour ABPM was recorded after 4 weeks of treatment with doxazosin GITS (-4 mg once daily in the morning), a new formulation of an α1-receptor inhibitor (W4). Nondippers were considered when mean blood pressure (BP) showed a ≤10% reduction during sleep. Statistical analyses included Saphiro-Wilks test, Student t test, and ANOVA.Results: After active treatment systolic, diastolic, and mean BP (SBP, DBP, MBP) significantly decreased during diurnal and 24 hours but not the nocturnal period. No significant change was observed for heart rate nor for pulse pressure during any period. The prevalence dippers increased from 0% to 17% after treatment. After placebo administration 8 among 37 RT with HT diagnosed according to casual BP remained hypertensive at nighttime (but not at daytime) according to 24-hour ABPM.Conclusions: Diurnal and 24-hour periods of ABPM showed significant changes in SBP, DBP, and MBP after active treatment with doxazosin GITS. No significant BP changes were observed in the nocturnal period or in dipper status. Further studies using ABPM must be undertaken to determine the optimal dosage and time of administration of antihypertensive drugs in RT. [Copyright &y& Elsevier]

Cities are gaining prominence committing to respond to the threat of climate change, e.g., by developing local climate plans or strategies. However, little is known regarding the approaches and processes of plan development and implementation, or the success and effectiveness of proposed measures. Mainstreaming is regarded as one approach associated with (implementation) success, but the extent of integration of local climate policies and plans in ongoing sectoral and/or development planning is unclear. This paper analyses 885 cities across the 28 European countries to create a first reference baseline on the degree of climate mainstreaming in local climate plans. This will help to compare the benefits of mainstreaming versus dedicated climate plans, looking at policy effectiveness and ultimately delivery of much needed climate change efforts at the city level. All core cities of the European Urban Audit sample were analyzed, and their local climate plans classified as dedicated or mainstreamed in other local policy initiatives. It was found that the degree of mainstreaming is low for mitigation (9% of reviewed cities; 12% of the identified plans) and somewhat higher for adaptation (10% of cities; 29% of plans). In particular horizontal mainstreaming is a major effort for local authorities; an effort that does not necessarily pay off in terms of success of action implementation. This study concludes that climate change issues in local municipalities are best tackled by either, developing a dedicated local climate plan in parallel to a mainstreamed plan or by subsequently developing first the dedicated and later a mainstreaming plan (joint or subsequent "dual track approach"). Cities that currently provide dedicated local climate plans (66% of cities for mitigation; 26% of cities for adaptation) may follow-up with a mainstreaming approach. This promises effective implementation of tangible climate actions as well as subsequent diffusion of climate issues into other local sector policies. The development of only broad sustainability or resilience strategies is seen as critical. • Trends in mainstreaming climate change issues were analyzed for 885 cities EU-28. • EU cities provide numerous local mitigation (#664) and/or adaptation (#321) plans. • Mainstreaming was investigated as vertical and horizontal approach. • 9% of cities have mainstreamed mitigation LCP; 12% of mitigation LCPs mainstreamed. • 10% of cities have mainstreamed adaptation LCP; 29% of adaptation LCPs mainstreamed. [ABSTRACT FROM AUTHOR]

Abstract: It has been analyzed samples of portland cement (PC) with and without admixtures, samples of calcium aluminate cement (CAC) with different content of Al2O3 and specimens of concrete made with PC and CAC using High Resolution Gamma Spectrometry. The activity concentration index (I) is much less than 0.5 mSv y−1 for all the concrete specimens according to the Radiation protection document 112 of the European Commission. The PC without admixtures (CEM I 52,5 R) and the PC with addition of limestone (CEM II/BL 32,5 N) also have an I value much lower than 0.5 and the PC with the addition of fly ash and blast furnace slag (CEM IV/B (V) 32,5 N and III/A 42.5 N/SR) have an I value close to 0.6. The I value of the CAC used in the manufacture of structural precast concrete is of the order of 1 mSv y−1. Some of the CAC used in refractory concrete reaches a value close to 2 mSv y−1. [Copyright &y& Elsevier]

Globally, efforts are underway to reduce anthropogenic greenhouse gas emissions and to adapt to climate change impacts at the local level. However, there is a poor understanding of the relationship between city strategies on climate change mitigation and adaptation and the relevant policies at national and European level. This paper describes a comparative study and evaluation of cross-national policy. It reports the findings of studying the climate change strategies or plans from 200 European cities from Austria, Belgium, Estonia, Finland, France, Germany, Ireland, Italy, Netherlands, Spain and the United Kingdom. The study highlights the shared responsibility of global, European, national, regional and city policies. An interpretation and illustration of the influences from international and national networks and policy makers in stimulating the development of local strategies and actions is proposed. It was found that there is no archetypical way of planning for climate change, and multiple interests and motivations are inevitable. Our research warrants the need for a multi-scale approach to climate policy in the future, mainly ensuring sufficient capacity and resource to enable local authorities to plan and respond to their specific climate change agenda for maximising the management potentials for translating environmental challenges into opportunities. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the study was to check for equivalence of computer codes that can perform calculations of true coincidence summing correction factors. All calculations were performed for a set of well-defined detector and sample parameters, without any reference to empirical data. For a p-type detector model the application of different codes resulted in satisfactory agreement in the calculated correction factors. For high-efficiency geometries in combination with an n-type detector and a radionuclide emitting abundant X-rays the results were scattered. [Copyright &y& Elsevier]

Urban areas are pivotal to global adaptation and mitigation efforts. But how do cities actually perform in terms of climate change response? This study sheds light on the state of urban climate change adaptation and mitigation planning across Europe. Europe is an excellent test case given its advanced environmental policies and high urbanization. We performed a detailed analysis of 200 large and medium-sized cities across 11 European countries and analysed the cities' climate change adaptation and mitigation plans. We investigate the regional distribution of plans, adaptation and mitigation foci and the extent to which planned greenhouse gas (GHG) reductions contribute to national and international climate objectives. To our knowledge, it is the first study of its kind as it does not rely on self-assessment (questionnaires or social surveys). Our results show that 35 % of European cities studied have no dedicated mitigation plan and 72 % have no adaptation plan. No city has an adaptation plan without a mitigation plan. One quarter of the cities have both an adaptation and a mitigation plan and set quantitative GHG reduction targets, but those vary extensively in scope and ambition. Furthermore, we show that if the planned actions within cities are nationally representative the 11 countries investigated would achieve a 37 % reduction in GHG emissions by 2050, translating into a 27 % reduction in GHG emissions for the EU as a whole. However, the actions would often be insufficient to reach national targets and fall short of the 80 % reduction in GHG emissions recommended to avoid global mean temperature rising by 2 °C above pre-industrial levels. [ABSTRACT FROM AUTHOR]

Abstract: The second part of an intercomparison of the coincidence summing correction methods is presented. This exercise concerned three volume sources, filled with liquid radioactive solution. The same experimental spectra, decay scheme and photon emission intensities were used by all the participants. The results were expressed as coincidence summing corrective factors for several energies of 152Eu and 134Cs, and different source-to-detector distances. They are presented and discussed. [Copyright &y& Elsevier]

Abstract: A comparison of the coincidence summing correction methods is presented. Since there are several ways for computing these corrections, each method has advantages and drawbacks that could be compared. This part of the comparison was restricted to point sources. The same experimental spectra, decay scheme and photon emission intensities were used by all the participants. The results were expressed as coincidence summing correction factors for several energies of 152Eu and 134Cs, and three source-to-detector distances. They are presented and discussed. [Copyright &y& Elsevier]

Abstract: Potentially harmful phosphate-based products derived from the wet acid digestion of phosphate rock represent one of the most serious problems facing the phosphate industry. This is particularly true for dicalcium phosphate (DCP), a food additive produced from either sulphuric acid or hydrochloric acid digestion of raw rock material. This study determined the natural occurring radionuclide concentrations of 12 DCP samples and 4 tricalcium phosphate (TCP) samples used for animal and human consumption, respectively. Metal concentrations (Al, Fe, Zn, Cd, Cr, As, Hg, Pb and Mg) were also determined. Samples were grouped into three different clusters (A, B, C) based on their radionuclide content. Whereas group A is characterized by high activities of 238U, 234U (∼103 Bqkg−1), 210Pb (2×103 Bqkg−1) and 210Po (∼800Bqkg−1); group B presents high activities of 238U, 234U and 230Th (∼103 Bqkg−1). Group C was characterized by very low activities of all radionuclides (<50Bqkg−1). Differences between the two groups of DCP samples for animal consumption (groups A and B) were related to the wet acid digestion method used, with group A samples produced from hydrochloric acid digestion, and group B samples produced using sulphuric acid. Group C includes more purified samples required for human consumption. High radionuclide concentrations in some DCP samples (reaching 2×103 and 103 Bqkg−1 of 210Pb and 210Po, respectively) may be of concern due to direct or indirect radiological exposure via ingestion. Our experimental results based on 210Pb and 210Po within poultry consumed by humans, suggest that the maximum radiological doses are 11±2μSvy−1. While these results suggest that human health risks are small, additional testing should be conducted. [Copyright &y& Elsevier]

Abstract: In an intercomparison exercise, the Monte Carlo codes most commonly used in gamma-ray spectrometry today were compared with each other in order to gauge the differences between them in terms of typical applications. No reference was made to experimental data; instead, the aim was to confront the codes with each other, as they were applied to the calculation of full-energy-peak and total efficiencies. Surprising differences between the results of different codes were revealed. [Copyright &y& Elsevier]

Heavy drinking and associated problems are relatively common in young men, including those in a military setting. This article explores characteristics of alcohol intake and associated difficulties and their relationship to a self-report of the usual intensity of response to alcohol in a sample of U.S. Marines. Two questionnaires related to demography and alcohol use histories, along with a simple, 12-item self-report measure of the usual number of drinks to experience an effect (the Self-Rating of the Effects of Alcohol, SRE) were administered to 1320 U.S. Marines. The sample had an average age of 22 years, 78% were Caucasian, and 92% were enlisted personnel. The relationships and correlations among drinking characteristics and problems and the usual number of drinks for an effect were determined. These subjects drank an average of 6 days per month, consuming an average of almost six drinks per drinking day, and reported more than three times per month in which they consumed six or more drinks per occasion. Consistent with studies of other populations, the SRE measures of intensity of response to alcohol showed a positive correlation with both drinking practices and problems, with the latter remaining significant even after controlling for recent drinking practices. The prodigious level of alcohol intake and associated problems, along with the SRE scores, indicate that the Marine Corps personnel are at especially high risk for alcohol-related life problems. These data also support the potential usefulness of the SRE both in identifying individuals likely to have more severe alcohol profiles and in educating individuals regarding their levels of risk for alcohol abuse and dependence. [ABSTRACT FROM AUTHOR]

An internal consistency test of the calculation of coincidence-summing correction factors F C for volume sources is presented. The test is based on exact equations relating the values of F C calculated for three ideal measurement configurations. The test is applied to a number of 33 sets of F C values sent by 21 teams. Most sets passed the test, but not the results obtained using the quasi-point source approximation; in the latter case the test qualitatively indicated the magnitude of the bias of F C. • A self-consistency test of coincidence summing calculations is presented. • It is based on equations relating F C values for 3 ideal volume geometries. • Can be easily applied in any laboratory for checking the quality of F C software. • 33 sets of F C values (various computations) for 60Co, 133Ba, 134Cs, 152Eu evaluated. • Inconsistency and bias of F C based on quasi-point source approximation revealed. [ABSTRACT FROM AUTHOR]

Monte Carlo (MC) simulation is widely used in gamma-ray spectrometry, however, its implementation is not always easy and can provide erroneous results. The present action provides a benchmark for several MC software for selected cases. The examples are based on simple geometries, two types of germanium detectors and four kinds of sources, to mimic eight typical measurement conditions. The action outputs (input files and efficiency calculation results, including practical recommendations for new users) are made available on a dedicated webpage. • Examples of the use of Monte Carlo simulation using different software. • Simple cases with two types of germanium detectors and four kinds of sources. • Calculation of full-energy peak and total efficiencies for 5 energies. • Input files and efficiency calculation results available on a dedicated webpage. [ABSTRACT FROM AUTHOR]