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C Otani

Publications and source records attributed to C Otani.

4 recordsLinked to original sources

Terahertz surface-wave resonant sensor with a metal hole array.

A surface-wave sensor based on the resonant transmission characteristics of metal hole arrays is demonstrated in the terahertz (THz) region. Since the frequency of the transmission peak of a metal hole array, which corresponds to the resonant frequency of the surface waves, is particularly sensitive to the refractive index in the vicinity of the metal surface, a very small change in the substances attached to the surface can be detected by monitoring the transmission spectrum. By attaching a layer of substance (thickness t < 5 microm) much thinner than the wavelength of the THz wave (lambda(THz) = 1 mm at 0.3 THz) to the surface of a metal hole array, we demonstrated that the existence of such a small amount of substance can be detected more easily than without the metal hole array. This demonstration of THz sensing with metal hole arrays indicates the possibility of realizing THz surface-wave sensors for biochemical molecules in the THz region.

Journal Article↗

Criterion validity of the cross-cultural cognitive examination in Japan.

Criterion validity of a two-stage Cross-Cultural Cognitive Examination (CCCE) designed for epidemiologic use was evaluated in Japanese subjects by comparison with a physician's DSM-III-R diagnosis of dementia and the Hasegawa Dementia Rating Scale (the standard Japanese instrument similar to the Mini-Mental State Exam). We report on 188 subjects tested in three locations in Japan: Tokyo area, Ise, and Osaka. Subjects ranged in age (50-93 years) and education (1-22 years) and included neurology outpatients, community volunteers, and inpatients. The CCCE was 97.4% specific for dementia, with sensitivity of 88%. The correlation with the Hasegawa scale was significant (r(175) = .8230, p less than .0001). Diagnosis using the CCCE showed good validity when compared with Japanese criteria for dementia. If the instrument could be shown to be reliable and more "culture fair" than the currently available tests, it may be useful in cross-cultural epidemiologic studies of dementia.

Aged↗

Lack of reactivity of paracoccidioidomycosis sera in the double immunodiffusion test with the gp43 antigen: report of two cases.

Sera from two patients with chronic active paracoccidioidomycosis yielded negative double immunodiffusion results with a culture filtrate antigen from Paracoccidioides brasiliensis routinely used in our laboratory. Complement fixation tests were positive for both sera using a polysaccharide-rich antigen. This study reports the results of a more extensive serological investigation of these two sera. Both a somatic antigen and a saline extract from the fungus yielded positive results in the double immunodiffusion. However, the immunodominant 43 kDa glycoprotein antigen showed negative results, although it was recognized by both sera in the Western blot assay. The value of the double immunodiffusion as a single serological test in paracoccidioidomycosis diagnosis is discussed.

Adult↗