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We described two female patients with primary Sjögren's syndrome associated with localized cutaneous nodular amyloidosis (LCNA), in which amyloid protein was derived from immunoglobulin light chain. Case 1; a 70-year-old female had complained with polyarthralgia, low-grade fever and parotid gland swelling. She was diagnosed as primary Sjögren's syndrome. Three years later she noticed brown color small tumor on the thigh and yellow to brown nodules on the bilateral calves of legs. Skin biopsy from the left thigh revealed amyloid L protein deposition, which was positive for anti-lambda light chain staining, in almost entire dermis. Infiltration of lymphocytes and plasma cells around the amyloid deposit were prominent. Case 2; a 51-year-old female had noticed increasing eruption on the hip. Skin biopsy revealed amyloid L protein deposition in the dermis, which was negative for anti-lambda nor kappa light chain staining. When she was refereed to our hospital, she complained of xerostomia and xerophthalmia. She was diagnosed as primary Sjögren's syndrome. In both cases, histological examination of a minor salivary gland biopsy revealed infiltration of lymphocytes and plasma cells but not amyloid deposit. Serum M protein and urine Bence-Jones protein were not detected. These cases represent localized amyloidosis without systemic involvement. It is widely recognized that Sjögren's syndrome is frequently accompanied by B cell lymphoproliferative disorders. In LCNA, infiltration of plasma cells around the amyloid deposits was frequently prominent. The relation between these two disorders is discussed.

The time dependency of filter performance across a high-efficiency particulate air (HEPA) filter was experimentally studied. The experimental study was carried out using a HEPA filter (203×203×150mm) clogged with liquid particles (mosquito stick aerosol). The aerosol concentration for filter loading was 0.84mg/m3 and the size distribution was similar to lognormal distribution (CMD=0.21μm, δg=1.65). The mass loading was about 60g/m2 when the pressure drop across the HEPA filter reached twice the initial pressure drop. The DOP particle penetrations through the HEPA filter were evaluated when relative pressure drops (ΔP/ΔP0) were nearly 1.0, 1.3, 1.4, 1.6, 1.8 and 2.1. The most penetrating particle size (MPPS) was almost independent of the mass loading if the face velocity was constant. However, the DOP particle penetration increased remarkably with mass loading, and the tendency of increase was not affected by particle size or face velocity.

To characterize airborne radioactivity induced by the operation of high-energy accelerators, the fractions of aerosol and gaseous components, and the chemical forms of 11 C, 13 N, and 15 O produced in the air of a target room of a 100 MeV electron linear accelerator were studied. Measurements of radioactivity using a particulate air sampling filter and a gas flow-through ionization chamber showed that more than 98% of 11 C, 13 N, and 15 O were present as gaseous forms. Their chemical forms, detected by means of radio-gas chromatography, were 11 C as CO 2 ; 13 N as N 2 and NO; and 15 O as O 2 and NO. Machine operating conditions, which affect the compositions of the induced radionuclides and of their chemical forms, and the resulting effect on the estimation of internal doses are discussed

From a practical angle of view to estimate the protection factors (PFs) provided by full-face masks, a number of protection factors were measured with a man-test apparatus just before the wearers started to do radiation work in radiation controlled area. PFs of the total number of 2, 279 cases were measured under five simulated working conditions. The measured PFs were widely distributed from 2.3 to 6, 700. About 95% of workers obtained PFs more than 50, and about 64% showed much higher PFs more than 1, 000 due to good fitting. In the case of some persons, the measured PFs irregularly varied and changed to a large degree. This method is a reliable technique that has been confirmed to protect unexpected internal exposure. From the results obtained, the method should be necessary to provide a better mask and higher PF for each worker.

Recently artificial intelligence (AI) which has functions of our interpretations and judgments has been applied to various fields of science.In the first application of AI to the transport procedure of the radioactive material, a prototype of expert system was developed with UTI-LISP programming language to appropriately classify mainly the packages and packagings according to regulations for the safe transport of radioactive material.Classification of the packages and packagings for the consignment is mainly determined from input informations such as radionuclides, its activities, states and conveyances through a forward reasoning method of the expert system.The rationalization of practice on our interpretations and judgments for transport of radioactive material including uniformity and reliability of our decision were confirmed as the result of an application to radiation control.

A mechanical breathing simulator has been developed to produce the human respiration for use in respirator test. The respirations were produced through the strokes of piston controlled by a rockerarm with adjustable fulcrum. The respiration rate was governed by motor-speed control, independent of the tidal volume achieved by adjustment of the piston stroke.By the breather, the simulated respirations for work rate 0, 208, 415, 622 and 830kg-m/min could be produced through the typical dummy head.

The performance of a respirator is governed mostly by the leakage through between mask and face. The leakage has been measured for three types of half mask and two types of full-face mask, worn by about forty persons, in order to examine the usefullness in actual application of the test method using NaCl particles. The particles generated with a nebulizer were fed into the hood in which the subject wore his respirator, and the concentration of NaCl in exhaled air was measured by a flame photometer. The measured values were corrected for the deposition of NaCl particles in the respiratory tract.The leakage of full-face masks differed largely with experience of the wearer. However, a few of persons tested could not be adjusted so as to avoid serious leakage.The problems in application of the present method to field test are also discussed.

The collection efficiency of nine types of filter papers for air sampling was determined for monodispersed polystyrene latex aerosols by using a forward light scattering photometer. The aerosols were 0.091, 0.198, 0.365, 0.500 and 1.099 mu m in dia., which flowed through a test filter paper at a face velocity from 4.2 to 200 cm/sec. Toyo No. 660, No. 60 and No. LP filter papers exhibited minimum efficiencies at the face velocity range between 10 and 80 cm/ sec, and in the particle size range between 0.1 and 0.5 mu m. The collection efficiencies of Toyo No. 5A and Whatman No. 41 filter papers were over 95% for all the particle sizes at a face velocity higher than 100 cm/sec. Toyo HE-40, HV- 70, Toyo GB-100 and Gelman E filter papers showed collection efficiencies higher than 99%. The theoretical filter efficiency based on single fiber filtering mechanisms and the effect of neighboring fiber interference on the collection efficiency are also discussed. (auth)

For the estimation of tritium surface contamination by a smear technique, some experiments have been made on the optimum content of glycerol loaded in the smear paper, the fraction of tritium removed by the paper from the surface contamination (i. e., removal efficiency), the counting efficiency for a 2π gas flow counter, and the desorption of tritium from contaminated smear papers.Of the total contamination, 1% and 10% can be removed using a 25w/o glycerol loaded smear paper from a permeable material such as synthetic polymer resin tile and a non-permeable one like stainless steel plate, respectively. The counting efficiency for a tritium smear sample is about 10% for the counter. It is therefore appropriate to assume that the overall counting efficiency in this method (removal efficiency multiplied by counting efficiency) is 0.1% and 1% for the above two materials, respectively. The desorption of tritium is much less from a glycerol loaded smear paper, being only 20% in 40min, while it is as high as 70% from the non-glycerol loaded one.

This experimental study has been performed to obtain fundamental data for in situ tests of activated charcoal filters installed in reactor exhaust systems using "R-112" as a tracer.The results have shown that the leakage flow less than 0.1% by channelings around gasket seals and the defects caused by settling in activated charcoal filters could be evaluated by analyzing the "R-112" adsorption efficiency curves. Moreover, it was found that the very high adsorption of "R-112" tracer on activated charcoal (more than 99.995%) was not affected by in situ test conditions such as temperature, humidity, flow velocity. These results agreed with those determined by the theoretical calculation, assuming that mass transfer through a gas film was the controlling factor in adsorption of "R-112" by activated charcoal.

A smear survey was performed under various experimental conditions, and the results obtained were compared with those of field tests. Non-permeable surface materials such as vinyl sheet were contaminated with various radioisotopes and smeared. The experiments showed that 50 approximates 80% of loose contamination and about 50% of total contamination were detected in the model experimertal conditions. On the other hand, the same experiments were also carried out using permeable materials. In this case, 50 approximates 80% of loose contamination and 2 approximates 50% of total contamination were detected. From these results, it was possible to estimate the amount of surface contamination, by assuming that 10 and 50% of the amount of total contamination are transferred to the smear disk for permeable and nonpermeable surface materials with contaminants, respectively. (P.C.H.)