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To predict how accurately neutron dosemeters can measure the neutron dose equivalent (rate) in MOX fuel fabrication facility work environments, the dose equivalent responses of neutron dosemeters were calculated by the spectral folding method. The dosemeters selected included two types of personal dosemeter, namely a thermoluminescent albedo neutron dosemeter and an electronic neutron dosemeter, three moderator-based neutron survey meters, and one special instrument called an Hp(10) monitor. The calculations revealed the energy dependences of the responses expected within the entire range of neutron spectral variations observed in neutron fields at workplaces. [ABSTRACT FROM PUBLISHER]

At the Nuclear Fuel Cycle Engineering Laboratories of the Japan Atomic Energy Agency (JAEA), small pieces of indium foil incorporated into personal dosemeters have been used for personnel screening in criticality accidents. Irradiation tests of the badges were performed using the SILENE reactor to verify the calibration of the indium activation that had been made in the 1980s and to recalibrate them for simulated criticalities that would be the most likely to occur in the solution process line. In addition, Monte Carlo calculations of the indium activation using the badge model were also made to complement the spectral dependence. The results lead to a screening level of 15 kcpm being determined that corresponds to a total dose of 0.25 Gy, which is also applicable in posterior–anterior exposure. The recalibration based on the latest study will provide a sounder basis for the screening procedure in the event of a criticality accident. [ABSTRACT FROM PUBLISHER]

The aim of this study is to propose action levels for chelation therapy in the case of inhalation of plutonium compounds using nose swabs. The relationship between the activity found in the nose swabs and early faecal excretion was investigated using actual cases at JAEA-NFCEL. The ratio was found to be in log-normal distribution. The action levels based on the activity of nose swab corresponding to 10 ALI ( 200 mSv) are determined for the facilities at JAEA-NFCEL by using the relationship and specific information such as isotopic ratio and physicochemical characteristics of plutonium compounds. [ABSTRACT FROM AUTHOR]

A new neutron-measuring instrument that is intended to measure a neutron personal dose equivalent, Hp(10) was developed. This instrument is composed of two parts: (1) a conventional moderator-based neutron dose equivalent meter and (2) a neutron shield made of borated polyethylene, which covers a backward hemisphere to adjust the angular dependence. The whole design was determined on the basis of MCNP calculations so as to have response characteristics that would generally match both the energy and angular dependencies of Hp(10). This new instrument will be a great help in assessing the reference values of neutron Hp(10) during field testing of personal neutron dosemeters in workplaces and also in interpreting their readings. [ABSTRACT FROM PUBLISHER]

The authors carried out an operational study that compared the use of TLD albedo dosemeters and solid state nuclear tracks detector in plutonium environments of Japan Nuclear Cycle Development Institute, Tokai Works. A selected group of workers engaged in the fabrication process of MOX (Plutonium-Uranium mixed oxide) fuel wore both TLD albedo dose- meters and solid state nuclear tracks detectors. The TL readings were generally proportional to the counted etch-pits, and thus the dose equivalent results obtained from TLD albedo dosemeter agreed with those from solid state nuclear tracks detector within a factor of 1.5. This result indicates that, in the workplaces of the MOX fuel plants, the neutron spectrum remained almost constant in terms of time and space, and the appropriate range of field-specific correction with spectrum variations was small in albedo dosimetry. [ABSTRACT FROM AUTHOR]

Olopatadine hydrochloride (olopatadine) is one of the second-generation antihistamines, which is prescribed for allergic disorders such as rhinitis, urticaria and eczema dermatitis.To investigate the possible anti-inflammatory effect of olopatadine on the chronic contact hypersensitivity response to repeated topical application of oxazolone in mice.The preventive and therapeutic effects of oral olopatadine were quantified by measurements of ear swelling, cytokine protein and mRNA expression in the ear lesion, and were compared with those of topical betamethasone 17-valerate (betamethasone).The ear receiving repeated applications of oxazolone exhibited erythema, oedema and abrasion. Both preventive and therapeutic administration of olopatadine (10 mg kg−1 day−1) significantly inhibited the ear swelling and the increased production of interleukin (IL)-4, IL-1β, granulocyte-macrophage colony-stimulating factor (GM-CSF) and nerve growth factor. In the histopathological analysis, olopatadine ameliorated epidermal hyperplasia and infiltration of inflammatory cells. Consistent with these results, olopatadine significantly reduced the increased expression of interferon-γ and IL-4 mRNA. Although betamethasone (0·012 mg ear−1 day−1) showed similar activities to olopatadine against these responses, it caused atrophy of the ear skin.These results indicate that olopatadine is an antihistamine agent having inhibitory activities against chronic inflammatory dermatitis, possibly resulting from its diminishing effect on elevated cytokines. [ABSTRACT FROM AUTHOR]