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Although understandings of scientific inquiry (as opposed to conducting inquiry) are included in science education reform documents around the world, little is known about what students have learned about inquiry during their elementary school years. This is partially due to the lack of any assessment instrument to measure understandings about scientific inquiry. However, a valid and reliable assessment has recently been developed and published, Views About Scientific Inquiry (VASI; Lederman et al. [2014], Journal of Research in Science Teaching, 51, 65-83). The purpose of this large-scale international project was to collect the first baseline data on what beginning middle school students have learned about scientific inquiry during their elementary school years. Eighteen countries/regions spanning six continents including 2,634 students participated in the study. The participating countries/regions were: Australia, Brazil, Chile, Egypt, England, Finland, France, Germany, Israel, Mainland China, New Zealand, Nigeria, South Africa, Spain, Sweden, Taiwan, Turkey, and the United States. In many countries, science is not formally taught until middle school, which is the rationale for choosing seventh grade students for this investigation. This baseline data will simultaneously provide information on what, if anything, students learn about inquiry in elementary school, as well as their beginning knowledge as they enter secondary school. It is important to note that collecting data from all of the approximately 200 countries globally was not humanly possible, and it was also not possible to collect data from every region of each country. The results overwhelmingly show that students around the world at the beginning of grade seven have very little understandings about scientific inquiry. Some countries do show reasonable understandings in certain aspects but the overall picture of understandings of scientific inquiry is not what is hoped for after completing 6 years of elementary education in any country.

[sup137]Cs sources are widely used in calibrations of radiation protection dosemeters and doserate meters. In these calibrations, conversion coefficients from the air kerma to various dose equivalent quantities are needed. These conversion quantities are functions of photon energy. In this work, Monte Carlo simulations and measurements are used for quantifying the energy distributions of the photon fluence from two [sup137]Cs sources used for calibration purposes. The results indicate that the standard set of conversion coefficients, obtained from a monoenergetic spectrum, do not sufficiently take into account the scattered radiation (most of which is scattered by the source itself): For the large (14 x 15.6 mm) and small (3.5 x 3 mm) [sup137]Cs sources, the simulated values for the conversion coefficients H'(0.07)/K[suba] and H*(10)/K[suba] (which were nearly equal for the both quantities) showed around 1.0 and 1.5% deviations from the ISO standard value 1.20 (for the large and small sources, respectively). Similarly, the conversion coefficient H[subp](10)/K[suba] showed around 1.5 and 2.5% deviations from the ISO standard value 1.21 for the large and small [sup137]Cs sources, respectively, whereas H[subp](0.07)/K[suba] had the values 1.22 and 1.23. The amplitude of the variation of the conversion coefficients due to varying [sup137]Cs source size did not exceed 1%. Thus, the overall uncer- tainty (with coverage factor k = 2) due to varying source size for the average values of the conversion coefficients can be estimated as low as 0.6%. [ABSTRACT FROM AUTHOR]

A thermoluminescence dosemeter (TLD)—entrance surface dose (ESD) phantom combination was calibrated in terms of air-kerma in IEC RQR X-ray radiation qualities between 50 and 150 kV. The ESD phantom was designed and constructed as a part of the work. With the combination, air-kermas were measured for four radiological examinations (two chest and two lumbar spine examinations in two hospitals), and converted to ESDa using Monte-Carlo calculated BSF data tabulated for different tube voltages, filtrations and beam diameters at 1 m distance. The results agreed with the ionisation-chamber measurements within the reported overall uncertainty of the TLD method. In the calibration, the ESD phantom can be replaced by the ISO water slab phantom unaffecting the reported overall uncertainty Backscatter-related parameters for the ISO water slab phantom and the newly designed ESD phantom were determined for the IEC RQR qualities used in the secondary standard dosimetry laboratory of STUK at 1 m distance, including an approximate Hp(10)/Hp(0.07) ratio. [ABSTRACT FROM AUTHOR]

The conversion coefficients from air kerma to ICRU operational dose equivalent quantities for STUK's realisation of the X-radiation qualities N-15 to N-60 of the ISO narrow (N) spectrum series were determined by utilising X-ray spectrum measurements. The pulse-height spectra were measured using a planar high-purity germanium spectrometer and unfolded to fluence spectra using Monte Carlo generated data of the spectrometer response. To verify the measuring and unfolding method, the first and second half-value layers and the air kerma rate were calculated from the fluence spectra and compared with the values measured using an ionisation chamber. For each radiation quality, the spectrum was characterised by the parameters given in ISO 4037-1. The conversion coefficients from the air kerma to the ICRU operational quantities Hp(10), Hp(0.07), H′(0.07) and H*(10) were calculated using monoenergetic conversion coefficients at zero angle of incidence. The results are discussed with respect to ISO 4037-4, and compared with published results for low-energy X-ray spectra. [ABSTRACT FROM AUTHOR]

Abstract: Design, spectrum measurements and simulations for an α-particle irradiator for bystander effect and genomic instability experiments are presented. Measured α-particle energy spectra were used to confirm the characteristics of the source of the irradiator specified by the manufacturer of the source. The spectra were measured in vacuum with a high-resolution spectrometer and simulated with an AASI Monte Carlo code. As a next step, we simulated α-particle energy spectra at the target plane of the irradiator for three different source-to-target distances. In these simulations, helium was used as the medium between the source and the exit window of the irradiator; its pressure and temperature corresponded to those of the ambient air. Mean energies and full-widths at half-maximum (FWHM) were calculated for the three different helium gas tracks. [Copyright &y& Elsevier]

137Cs sources are widely used in calibrations of radiation protection dosimeters and doserate meters. In these calibrations, conversion coefficients from the air kerma to various dose equivalent quantities are needed. These conversion quantities are functions of photon energy. In this work, Monte Carlo simulations and measurements are used for quantifying the energy distributions of the photon fluence from two 137Cs sources used for calibration purposes. The results indicate that the standard set of conversion coefficients, obtained from a monoenergetic spectrum, do not sufficiently take into account the scattered radiation (most of which is scattered by the source itself): For the large (14x15.6 mm) and small (3.5x3 mm) 137Cs sources, the simulated values for the conversion coefficients H'(0.07)/Ka and H*(10)/Ka (which were nearly equal for the both quantities) showed around 1.0 and 1.5% deviations from the ISO standard value 1.20 (for the large and small sources, respectively). Similarly, the conversion coefficient Hp(10)/Ka showed around 1.5 and 2.5% deviations from the ISO standard value 1.21 for the large and small 137Cs sources, respectively, whereas Hp(0.07)/Ka had the values 1.22 and 1.23. The amplitude of the variation of the conversion coefficients due to varying 137Cs source size did not exceed 1%. Thus, the overall uncertainty (with coverage factor k=2) due to varying source size for the average values of the conversion coefficients can be estimated as low as 0.6%.