In case of a nuclear reactor accident affecting a large population the internal contamination of the workers and the public can be assessed through in vivo measurements. Since iodine-131 is one of ...the most important releases and since it is of health concern, thyroid monitoring of this radionuclide is of special interest.
Intercomparisons of thyroid in vivo measurements usually focus on the adult case. Here we report about a European intercomparison exercise for spectroscopic devices. Three sets of thyroid phantoms of unknown activity were circulated, representing the following ages: 5 years-old, 10 years-old and the adult.
Nineteen institutions from twelve countries in Europe took part in an intercomparison exercise. Twenty-nine measurement devices have been tested. In the adult case, 5 results were outside the acceptance criteria and 10 in the 10-years old case. In the 5 years-old case, the result was not reported for one measurement device and 11 results were outside the acceptance criteria. Devices that have been tested during this intercomparison now dispose of calibration coefficients for the three age groups.
•Children thyroid measurements are important in case of nuclear reactor accident.•Laboratories could check their ability to measure iodine contamination in thyroid.•Opportunity was given to calibrate for children thyroid measurement.•Measurement capacity in Europe increased from this intercomparison exercises.
In an examination of how adolescents reason about several factors related to division of childcare labor, 38 adolescents, including 20 girls (M age = 16.36 years, SD = .50) and 18 boys (M age = ...16.59 years, SD = .62) were interviewed about conflicts between a mother and a father over which parent should stay home with the child, the authority of the father, and similar issues in a traditional culture. The relative income of each parent was varied. Participants considered the needs of the child most when reasoning about infants, and the right to work most frequently when reasoning about preschoolers (p < .001, η
2
= .35). The majority (71%) did not endorse the husband's authority over the wife. However, boys were more likely than girls to emphasize the mother's responsibility to the child over her right to work (p < .01, η
2
= .23). Implications for gender equity and adolescents' future goals were discussed.
BABAR CsI calorimeter design and first beam test results Brose, J
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/1996, Letnik:
379, Številka:
3
Journal Article
Recenzirano
The BABAR detector at the PEP-II B-factory at SLAC is designed to measure CP violation in the decays of B mesons. In order to meet the physics aims of the experiment the target energy resolution for ...photons at a polar angle of 90° is:
σ
E/E=(1%/
4
E GeV
)
⊕ 1.2%. This requires a minimum equivalent noise energy of about 150 keV per crystal. Using two 1 × 2 cm
2 photodiodes for direct readout of full-size crystals a photoelectron yield of about 8000 e
−/MeV and equivalent noise energies below 100 keV were obtained in the laboratory.
A first beam test using a 5 × 5 array of crystals was performed in the fall of 1995 at an electron/pion beam at PSI. Data were collected at different energies between 100 MeV and 400 MeV allowing the determination of energy and angular resolution as a function of energy, impact position and angle of incidence. Results of a first analysis of these data are presented.
Patients with cancer are at high risk to develop venous thromboembolism, and they are also more likely to develop complications from anticoagulant treatment. Because little research has focused on ...the oncology population to date, the optimal methods of prophylaxis and treatment remain uncertain in some clinical situations. Currently, low molecular weight heparin and warfarin are the most frequently used pharmacologic agents; however, they have their limitations. Other therapeutic options, such as inferior caval filters, are poorly studied and remain controversial. A summary of the most recent evidence on the prevention and treatment of venous thromboembolism in cancer patients is presented here.
A photomultiplier setup for precise relative CsI(Tl) crystal light yield and uniformity measurements is described. It is used for wrapping material studies to optimize the uniformity and the yield of ...the light output of 36
cm long crystals. The uniformity is an important property in high energy photon calorimetry. Results of an optimization of photodiode coupling to crystals, the influence of temperature and radiation damage to light and photoelectron yield are also presented.
The mass and total width of the eta_c meson have been measured in two-photon interactions at the SLAC asymmetric B-Factory with the BABAR detector. With a sample of approximately 2500 reconstructed ...eta_c -> Ks K pi decays in 88 fb-1 of data, the measured eta_c mass and width are respectively 2982.5 +- 1.1 (stat) +- 0.9 (syst) MeV/c2 and 34.3 +- 2.3 (stat) +- 0.9 (syst) MeV/c2. Using the same decay mode, a second resonance with 112 +- 24 events is observed with a mass of 3630.8 +- 3.4 (stat) +- 1.0 (syst) MeV/c2 and width of 17.0 +- 8.3 (stat) +- 2.5 (syst) MeV/c2. This observation is consistent with expectations for the eta_c(2S) state.
A membrane‐based extraction process is described for the fractionation of citrus oils to produce an oil stream enriched in oxygenated components. The process relies on the high selectivity of ...cyclodextrins (CDs) to preferentially bind the desirable oxygenates. In the process, low‐temperature citrus oil flows on one side of a nonporous membrane, and an aqueous CD solution flows on the other side of the membrane. Oxygenates diffuse through the water‐swollen hydrophilic membrane and preferentially partition into the aqueous CD solution. The aqueous CD solution is then heated and circulated past a second membrane, where the CD/oxygenate complex dissociates and the liberated oxygenates diffuse into a citrus oil solution. Disassociated CD is recycled to the first membrane. Data are presented on the effect of temperature and CD type on the partitioning of oxygenates from orange oil into aqueous CD solutions. Operation of a pilot‐scale test loop that capitalizes on the high selectivity of CDs and the temperature dependence of the CD binding is described for the production of oxygenate‐enriched orange oil.
This double blind, placebo-controlled study examined the effects of an opiate antagonist, naltrexone, on nociceptive flexion reflex (NFR) thresholds and subjective pain in individuals with and ...without a parental history of hypertension. Using a repeated measures design, NFR threshold was repeatedly assessed on two testing days after administration of either placebo or naltrexone. Immediately after NFR threshold was determined, participants rated the level of pain experienced during the preceding NFR assessment, and at the end of each session participants’ electrocutaneous pain threshold was assessed. Two primary findings were obtained. First, individuals with a parental history of hypertension exhibited attenuated pain sensitivity. Second, endogenous opioid blockade was associated with increased pain ratings in women but with increased pain threshold in men. In sum, the present study did not support a direct involvement of the endogenous opioid system in the attenuated pain sensitivity observed in individuals at increased risk for hypertension.
The BB detector: Upgrades, operation and performance Martinelli, M.; Zhu, Y.S.; Gill, M.S. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/2013, Letnik:
729, Številka:
C
Journal Article
The inhalation of 222Rn and its short-lived decay products results in the exposure of the respiratory tract followed by the skeletal deposition of 210Pb originating in the lung from 214Po. By ...measurement of the 210Pb activity in the skull it could be possible to estimate previous exposures for a known relationship between 210Pb content in the skeleton and exposure. The measurement technique consists of two arrays of low energy germanium detectors (LEGe) with a total active area of 8000 mm2 installed in a large shielded chamber. The interpretation of estimated 210Pb deposit in terms of exposure can be made by using 'conversion coefficients' KE(tm) for the relationship between the 210Pb activity A(tm) and cumulative exposure. The decision limit of 210Pb for the total skeleton in a counting time of 7200 s was estimated to be 17 Bq, or about 0.9 J.h.m-3 (250 WLM) of exposure. The results of the first measurements of a group of individuals living in high radon prone areas show a good qualitative correspondence with the expected 210Pb content of the skeleton.
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