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SiO 2 films were deposited on glass wafers using energy treatment sputtering (ETS). Surface roughness S a of ETS-SiO 2 film was 0.17 nm, which is remarkably smaller than that of films deposited using conventional sputtering (Sa=0.46 nm). Bonding using the extremely smooth surface was demonstrated.

Rutherford backscattering spectrometry (RBS) with swift ion probes is generally known as a non-destructive characterization technique for metal and semiconductor samples. On the other hand, it is also known that the technique may cause severe damages on organic insulators such as polyimide films. In this work, using the ERD (elastic recoil detection) and the RBS techniques simultaneously, the irradiation damage in a polyimide sample (Kapton-H) induced by 1.5 MeV helium ions has been evaluated by monitoring the evolution of depth profiles of hydrogen and oxygen while increasing the fluence of the primary helium ions from 1.4 × 10 14 to 2.8 × 10 15 cm −2 . In the surface region of the polyimide sample, where electronic stopping is predominant, a progressive hydrogen depletion approaching 50% of the amount contained in a pristine sample has been observed. At the same time, a gradual depletion of oxygen in the near surface region of the irradiated sample has been observed.

A characterization technique for oxide ferroelectric materials using high-energy ion beam is presented. In this study, depth profiles of chemical elements are obtained for SBT films grown by MOD method and by MOCVD method respectively. Hydrogen depth profiles are taken by ERD technique with an Al absorber foil. Depth profiles of other elements are determined with RBS technique. For the MOD-grown sample, the elemental amount ratio was determined as Sr1.00Bi2.06 ± 0.03Ta2.02 ± 0.03O8.33 ± 0.17. The oxygen deficiency in the MOD-grown SBT film was uniformly observed at every depths. For the MOCVD-sample and the MOD-sample, the underlying Pt electrode layers contained 4.7 at.% and 3.8 at.% of hydrogen respectively.

The modifying effects of flavonoids diosmin and hesperidin during the initiation and post-initiation phases of oesophageal carcinogenesis initiated with N-methyl-N-amylnitrosamine (MNAN) were investigated in male Wistar rats. At 7 weeks of age, all animals except those treated each test chemical alone and control groups were given weekly intraperitoneal injections of MNAN (12.5 mg/kg body weight/injection) for 12 weeks to induce oesophageal neoplasms. For examining the modifying effects of 'initiation' treatment of test compounds, groups of animals were fed the diets containing 1000 ppm diosmin and 1000 ppm hesperidin, and the diet containing both compounds (900 ppm diosmin and 100 ppm hesperidin) for 13 weeks, starting 7 days before the MNAN dosing and then switched to the basal diet. For examining the modifying effects of 'post-initiation' treatment of these compounds, the groups given MNAN and a basal diet were switched to the experimental diets containing diosmin, hesperidin or diosmin combined with hesperidin at 1 week after the stop of MNAN injection, and maintained on these diets for 7 weeks. The other groups consisted of rats given test compounds alone or untreated rats. All animals were necropsied at the termination of the study (week 20) to determine the incidences of oesophageal neoplasms and preneoplasms, blood polyamine levels, and cell proliferation activity estimated by 5-bromodeoxyuridine (BrdU)-labelling index and by morphometric analysis of silver-stained nucleolar organizer regions' protein (AgNORs). A number of oesophageal neoplasms developed in rats treated with MNAN alone (75% and 100% incidences of carcinoma and papilloma, respectively). 'Initiation' feeding of diosmin significantly decreased the incidence of squamous cell carcinoma (P < 0.05). Also, 'initiation feeding' of both compounds singly or in combination caused a significant reduction in the multiplicities of oesophageal carcinoma and papilloma (diosmin, 78 and 58% reduction; hesperidin, 70 and 50% reduction; and the combination regimen, 70 and 30% reduction, P < 0.005). 'Post-initiation' feeding slightly decreased the multiplicities of these oesophageal neoplasms. Also, these dietary regimens reduced the multiplicities of preneoplastic lesions (hyperplasia and severe dysplasia; P < 0.05). There were no pathological alterations in rats treated with both compounds alone or the combined regimen alone or those in an untreated control group. Similarly, feeding of these compounds significantly decreased the expression of cell proliferation biomarkers (BrdU-labelling index and AgNORs number) of the non-lesional oesophageal epithelium (P < 0.05). Blood polyamine concentrations were also lowered in rats given the carcinogen and test compounds, both alone and in combination, when compared with those of rats given MNAN alone (P < 0.05). These findings suggest that diosmin and hesperidin supplementation, individually or in combination, is effective in inhibiting the development of oesophageal cancer induced by MNAN when given during the initiation phase, and such inhibition might be related to suppression of increased cell proliferation caused by MNAN in the oesophageal mucosa.

To investigate the utilities of a shed snake skin as a model membrane for preclinical studies of transdermal drug delivery, the flux of indomethacin was determined under various conditions by using a diffusion cell. The flux of fatty alcohols was determined and compared with that in human skin reported in references. The esterase activity of shed snake skin was also determined. It was found that the flux of indomethacin decreased with an increase of pH and the amount of ethanol in a vehicle. The flux of indomethacin increased by the addition of Azone, N-methyl−2−pyrroridone and N,N-dimethyl-m-toluamide in the cream. The flux of fatty alcohols in shed snake skin was greater than that reported in human skin, and shed snake skin had similar esterase activity to human skin.

A magneto-active microwave plasma chemical vapour deposition technique was developed by pulse modulation of the discharge to reduce the time-averaged microwave power for diamond film synthesis at low temperature. Due to a threshold power being required to start growth, the practical growth rate obtained by using the pulse-modulated plasma became three times larger than that obtained by using a continuous plasma of time-averaged power near the threshold. The methyl radical density was measured in continuous or pulse-modulated plasma by infrared laser absorption spectroscopy and compared to the growth rate. The time-averaged radical density was also enhanced by pulse modulation; it was up to 1.3 times larger than that in the continuous plasma. Though the correlation between density and diamond growth rate was not clear, the number of carbon atoms supplied as radicals was larger than the actual growth rate by almost two orders of magnitude.

Co, Ni, and Pt metal thin films have been formed using the pulsed laser deposition method. Several fundamental properties of this method, e.g., deposition rate for the KrF excimer laser with various irradiation energy densities, distribution of film thickness, change of the deposition rate as a function of the number of shots, change of the target morphology, and corresponding film structure, are examined. It is found that the deposition rate and the film structure (amorphous and/or polycrystalline) depend on the state of the morphology of the target. An attempt to control the target morphology was performed, i.e., the rotation of the Co target restrained the target surface from the formation of laser cones and as a result, the amorphous Co films could be obtained.

The prevalence of thyroid dysfunction in relation to iodine intake was studied in adults (n = 1061) in five coastal areas of Japan that produce iodine-rich seaweed (kelp). The prevalence of hyperthyroidism (TSH0.15 mU/L) was similar in these areas, whereas that of hypothyroidism (TSH5.0 mU/L) varied from 0-9.7%. The relative frequency of above normal iodide concentration in the morning urine (or = 75 mumol/L) [high urinary iodide (UI)] varied from 3.7%-30.3%. Together with previously reported results of a noncoastal city, the frequency of high UI correlated significantly with that of hypothyroidism with negative thyroid autoantibody (r = 0.829, n = 6, P0.05) but not with positive thyroid autoantibody (r = 0.278, NS) or with that of hyperthyroidism (r = 0.038, NS). Hypothyroidism was more prevalent in thyroid autoantibody-negative subjects with high UI (group II, 12.1%) than with normal UI (group I, 2.3%) (P0.001). The TSH [21.9(6.5-73.7)mU/L] (mean +/- SD) and thyroglobulin [288 (182-456) micrograms/L] levels in group II were significantly higher than the respective levels in group I [9.6(3.7-25.3)mU/L and 123 (38-399) micrograms/L] (P0.05). Free T4 of group II (9.9 +/- 3.9 pmol/L) was significantly lower than in group I (14.2 +/- 3.9 pmol/L) (P0.05). These results indicate that 1) the prevalence of hypothyroidism in iodine sufficient areas may be associated with the amount of iodine ingested; 2) hypothyroidism is more prevalent and marked in subjects consuming further excessive amounts of iodine; and 3) excessive intake of iodine should be considered an etiology of hypothyroidism in addition to chronic thyroiditis in these areas.

Lafutidine is a unique histamine H(2)-receptor antagonist (H2RA) that has a sensitizing effect on capsaicin-sensitive afferent neurons (CSAN). This effect may make lafutidine useful for the treatment of burning mouth syndrome (BMS).To evaluate the efficacy and safety of lafutidine in patients with oral burning sensation, a randomized controlled trial was performed. Patients who had been receiving other H2RAs with no sensitizing effect on CSAN were randomly assigned to receive lafutidine 10 mg twice daily for 12 weeks, instead of the previous H2RAs, plus gargling with azulene sulfonate sodium (ASS) (lafutidine group, n = 36) or to continue to receive the previous H2RAs plus ASS gargling (control group, n = 35). The intensity of burning sensation was scored by means of a visual analog scale (VAS).Thirty-four patients in the lafutidine group and 30 in the control group completed the study. In the lafutidine group, the rate of improvement in the VAS score as compared with the baseline value was significant after 4, 8, and 12 weeks of treatment (P0.05). The improvement rate was consistently higher in the lafutidine group than in the control group; the differences between the groups were significant (P0.05) after 4, 8, and 12 weeks of treatment. Only two mild abdominal adverse events occurred in the lafutidine group, but neither required the termination of treatment.Oral lafutidine is very safe and effective for reducing the intensity of oral burning sensation and may therefore be a viable option for the treatment of BMS.

The present experiment aims to investigate the Reynolds number dependence of fine-scale coherent eddies called elementary vortices universally existing in various turbulence fields. The elementary vortices were detected in stable-stratified grid turbulence, homogeneous shear turbulence and a nocturnal surface layer of which turbulence Reynolds number, R λ , ranges from 19 to 2391. The conditional sampling was conducted referring to the steep change in transverse component of velocity fluctuation peculiar to the Burgers vortex. The resultant wave traces given by conditional averaging assured the existence of the elementary vortex similar to the Burgers vortex in all of the turbulence fields. The diameter of the elementary vortex was estimated to be about 10 times of the Kolmogorov scale being regardless of R λ . The maximum azimuthal velocity normalized by the Kolmogorov velocity increased in proportion to R λ 0.28 R λ 0.28 except for the data obtained in shear flow fields. Such dependence accords with the scaling law for the elementary vortex introduced by DNS studies.

We have reported the seeding pretreatment for Chemical Vapor Deposition (CVD) using nanocrystal diamond particles of 5 nm in average size [1,2]. In this work, we attempted to seed Si substrates with well purified and well-dispersed nanocrystal diamond particles for the synthesis of diamond films by a magneto-active microwave plasma CVD or a conventional microwave plasma CVD. We achieved ultrahigh growing particle density of 2 × 1011 cm−2. On the seeded substrate the diamond films were formed in short time because the nucleation process was not necessary.

This paper describes selective area PZT-preparation based on PZT precursor etching for sol-gel method, and its application to the fabrication of PZT disk transducers of nearly 1 /spl mu/m thickness without repeating any process. Using this method, we show that PZT disk transducers of 0.8 /spl mu/m thickness can be fabricated only by a single process. The piezoelectricity of the transducers is discussed by an ultrasonic pulse echo method.

Low-threshold-current (20 mA) 670 nm multiquantum-well laser diodes (LDs) for bar-code readers (BCRs) and laser pointers have been developed. A marked reduction in power consumption (40% lower than conventional bulk LDs) and a maximum CW temperature of 110 degrees C have been realised simultaneously. Estimated lifetimes of more than 10000 h, which is sufficient for both BCRs and laser pointers, were obtained at 5 mW, 60 degrees C, with operating currents of less than 40 mA. >

There are increasing demands for low-power-consumption 670nm-band red-light-emitting laser diodes (LDs) in applications such as handy bar-code scanners, etc. In this paper the authors have developed low-threshold-current multi-quantum-well (MQW) LDs with a short-length-cavity and a high-reflectivity (HR) rear facet. Marked reduction in threshold currents has been achieved by using MQW as an active layer and by optimizations of cavity lengths considering temperature characteristics in a trade-off relation between low-threshold-currents and high-temperature-operations. Moreover, the reflectivity of a rear facet was increased to a maximum value (80%) where necessary monitor currents for an automatic-power-control could be maintained. For 150/spl mu/m-long LDs, threshold current was reduced to 12.6mA (1/3 of conventional LDs), maintaining sufficient temperature characteristics for 50/spl deg/C use. For 350/spl mu/m-long LDs, consumption power was reduced to 1/2 of conventional LDs and long lifetimes at 60/spl deg/C have been obtained.

Through one-point conditional hotwire measurements, a three-dimensional configuration was illustrated about a large-scale coherent vortex in a turbulent boundary layer. Coherent vorticity vector maps gave it a horseshoe sculpture. The horseshoe vortex induces four kinds of coherent structures; the strong outflow (ejection) between a pair of its legs, the inrush (sweep) outside the legs, the large-scale u-discontinuity upstream of the outflow and its head conforms to the turbulent bulge in the outer layer. Its coherent energy is mainly produced by the outflow. The legs play dominant roles in the energy and momentum transfer by the coherent motions and the head makes turbulent bulge with obscure structure. The coherent energy budget showed that coherent production, random production and random diffusion terms mainly contributed to the energy transfer about the large-scale coherent vortex.

The modifying effect of dietary administration of auraptene isolated from the peel of citrus fruit (Citrus natsudaidai Hayata) on the development of azoxymethane (AOM)-induced colonic aberrant crypt foci (ACF) was investigated in rats. Male F344 rats were given s.c. injections of AOM (15 mg/kg body wt) once a week for 3 weeks to induce ACF. They also received diets containing 100 or 500 p.p.m. auraptene for 5 weeks, starting 1 week before the first dose of AOM. At termination of the study (week 5) dietary administration of auraptene caused a significant reduction in the frequency of ACF in a dose-dependent manner (P < 0.05). Feeding of auraptene suppressed expression of cell proliferation biomarkers (5-bromo-2'-deoxyuridine labeling-index, ornithine decarboxylase activity, polyamine content and number of silver stained nucleolar organizer region protein particles) in the colonic mucosa and the occurrence of micronuclei caused by AOM. Also, auraptene increased the activities of phase II enzymes (glutathione S-transferase and quinone reductase) in the liver and colon. These findings might suggest that inhibition of AOM-induced ACF may be associated, in part, with increased activity of phase II enzymes in the liver and colon and suppression of cell proliferation in the colonic mucosa.

Among the organoselenium compounds, 1,4-phenylenebis(methylene) selenocyanate (p-XSC) is reported to exert the most effective chemopreventive effect on chemically induced carcinogenesis in the mammary glands, colon, and lung of laboratory animals. This study was designed to test the inhibitory effects of dietary p-XSC (5 and 15 ppm as selenium) during the initiation phase (1 week before, during, and up to 1 week after the carcinogen exposure) and the postinitiation phase (1 week after carcinogen administration until termination) on the formation of neoplasms of the tongue induced in male F344 rats by 4-nitroquinoline-1-oxide (4-NQO). The doses of p-XSC were 20% (5 ppm selenium) and 60% (15 ppm selenium) of maximum tolerated dose levels. At 6 weeks of age, all rats except those given p-XSC alone and those in untreated groups were treated with 4-NQO (20 ppm in the drinking water for 8 weeks). Dietary p-XSC, administered at selenium levels of 5 and 15 ppm during either the initiation or postinitiation phases, significantly reduced the incidence of carcinoma of the tongue. p-XSC was especially effective when it was administered at 15 ppm selenium during the postinitiation phase, in which case it completely inhibited the development of tongue carcinoma (from 47% in the dietary control to 0%). Glutathione S-transferase activities in the liver and tongue of rats treated with 4-NQO and p-XSC were significantly elevated compared to those in rats treated with 4-NQO alone. Similarly, quinone reductase activity was significantly elevated in the liver but decreased in the tongue (posterior portion). Such modulation by p-XSC in the phase II enzyme activities of the liver and tongue might be related to inhibition of the initiation. In addition, the expression of cell proliferation biomarkers, such as polyamine level, ornithine decarboxylase activity, 5-bromodeoxyuridin-labeling index, and argyrophilic nucleolar organizer's protein number, in the epithelium of the tongue was significantly reduced in rats that were fed thep-XSC diets compared to those who were fed the basal diet. Such alteration in cell proliferation through modulation of ornithine decarboxylase activity and polyamine biosynthesis in the tongue epithelium might be related to inhibition occurring in the postinitiation phase of carcinogenesis. The dose levels of p-XSC used induced no toxicity or alteration in body weight gain. Although the precise mechanisms of p-XSC-induced inhibition of tongue carcinogenesis remains to be elucidated, it is evident that p-XSC has powerful chemopreventive efficacy against tongue carcinogenesis.

The modulating effects of dietary feeding of two flavonoids, diosmin and hesperidin, both alone and in combination, during the initiation and post-initiation phases on colon carcinogenesis initiated with azoxymethane (AOM), were investigated in male F344 rats. Animals were initiated with AOM by weekly s.c. injections of 15 mg/kg body wt for 3 weeks to induced colon neoplasms. Rats were fed the diets containing diosmin (1000 ppm), hesperidin (1000 ppm) or diosmin (900 ppm) + hesperidin (100 ppm) for 5 weeks (initiation treatment) or 28 weeks (post-initiation treatment). The others contained the groups of rats treated with diosmin, hesperidin alone or in combination, and untreated. At the end of the study (32 weeks), the incidence and multiplicity of neoplasms (adenoma and adenocarcinoma) in the large intestine of rats initiated with AOM together with, or followed by, a diet containing diosmin or hesperidin were significantly smaller than those of rats given AOM alone (P

The modifying effects of the two flavonoids diosmin and hesperidin given during the initiation and postinitiation phases of oral carcinogenesis initiated with 4-nitroquinoline 1-oxide (4-NQO) were investigated in male F344 rats. The compounds were tested alone and in combination. At 6 weeks of age, animals were divided into experimental and control groups and fed diets containing 1000 ppm diosmin and 1000 ppm hesperidin and a diet containing both compounds (900 ppm diosmin and 100 ppm hesperidin). At 7 weeks of age, all animals except those treated with each test chemical alone and control groups were given 4-NQO (20 ppm) in the drinking water for 8 weeks to induce oral cancer. Starting 7 days before the 4-NQO exposure, groups of animals were fed the diets containing test chemicals for 10 weeks and then switched to the basal diet. Starting 1 week after the cessation of 4-NQO exposure, the groups given 4-NQO and a basal diet were switched to the diets containing diosmin, hesperidin, or diosmin combined with hesperidin and maintained on these diets for 22 weeks. The other groups consisted of rats given diosmin (1000 ppm), hesperidin (1000 ppm), and the combination regimen of these two compounds (900 ppm diosmin with 100 ppm hesperidin) alone, and untreated rats. All animals were necropsied at the termination of the study (week 32). The incidences of tongue lesions (neoplasms and preneoplasms), polyamine levels in the tongue tissue, and cell proliferation activity estimated by a 5-bromodeoxyuridine-labeling index and by morphometric analysis of silver-stained nucleolar organizer regions protein were compared among the groups. Feeding of both compounds singly or in combination during the initiation phase caused a significant reduction in the frequency of tongue carcinoma [diosmin, 68% reduction (P0.01); hesperidin, 75% reduction (P0.005); and the combination regimen, 69% (P0.05)]. When fed the test compounds singly or the combination regimen after 4-NQO exposure, the frequency of tongue cancer was also decreased [diosmin, 77% reduction (P0.005); hesperidin, 62% reduction (P0.05); and the combination regimen, 77% (P0.005)]. The incidences of oral preneoplasia (hyperplasia and dysplasia) in these groups were also decreased when compared with carcinogen controls (P0.05-P0.001). There were no pathological alterations in rats treated with test compounds or the combined regimen alone or those in an untreated control group. Dietary administration of these compounds significantly decreased the expression of cell proliferation biomarkers (5-bromodeoxyuridine-labeling index and silver-stained nucleolar organizer regions protein number) of the nonlesional tongue squamous epithelium (P0.05). Also, polyamine concentrations in the oral mucosa were lowered in rats given the carcinogen and test compounds, alone and in combination, compared with those of rats given 4-NQO alone (P0.05). These findings suggest that supplementation with the flavonoids diosmin and hesperidin, individually and in combination, is effective in inhibiting the development of oral neoplasms induced by 4-NQO, and such inhibition might be related to suppression of increased cell proliferation caused by 4-NQO in the oral mucosa.

Fuji Television's new broadcast center facilities have recently been installed and are now in fully operational, starting in March 1997. The new broadcast center employs a newly developed optical video/audio signal distribution network. This paper describes the system structure and performance of the optical network. A Wavelength-Division and Time Division hybrid multiplexed (WD/TD) optical network has been applied to the broadcast center. This type of optical network is attractive for a broadcast center application, because of its large capacity, multiple format handling, and flexible operation capabilities. The optical network utilizes 16-channel Wavelength-Division Multiplexing (WDM) technology and 16-channel Time Division Multiplexing (TDM) technology for 143Mb/s NTSC composite video signals (TDM high-way speed: 2.29Gb/s). By using these technologies, the optical network distributes about 150 digital NTSC composite video combined with audio signals, together with about 15 HDTV signals (1.5Gb/s), to 20 studios and control rooms. This new system of operation has drastically reduced the operator work load in the signal distribution center.

Described here is the wavelength-division and time-division hybrid multiplexed (WD/TD) optical network which has been practically implemented in the Fuji Television's new broadcast center. The network has a maximum throughput exceeding 70 Gb/s and is used to distribute about 150 digital NTSC video signals as well as 15 HDTV signals.

The modifying effects of dietary exposure of three flavonoids, chalcone, 2-hydroxychalcone, and quercetin, during the initiation and postinitiation phases of oral tumorigenesis initiated with 4-nitroquinoline-1-oxide (4-NQO) were investigated in male F344 rats. At 6 weeks of age, animals were divided into experimental and control groups. At 7 weeks of age, all animals except those treated with test chemicals alone and the untreated control group were given 4-NQO [20 parts/million (ppm)] in the drinking water for 8 weeks to induce oral neoplasms. For chemopreventive study by feeding of test compounds during the initiation phase, groups of animals were given diets containing 500 ppm chalcone, 500 ppm 2-hydroxychalcone, or 500 ppm quercetin for 10 weeks, starting 1 week before 4-NQO exposure. Seven days after stopping 4-NQO exposure, these groups were switched to the basal diet and kept on this diet until the end of the experiment. For chemopreventive study by treatment with test chemicals during the postinitiation phase, starting 1 week after the cessation of 4-NQO administration, the groups given 4-NQO and the basal diet were switched to the diets mixed with test chemicals and maintained on these diets for 22 weeks. The other groups consisted of rats fed diets containing 500 ppm test chemicals alone or of untreated rats. Thirty-two weeks after the start of the study, the incidence of tongue neoplasms and preneoplastic lesions, polyamine levels in the tongue epithelium, and cell proliferation activity estimated by bromodeoxyuridine labeling index were compared among the different dietary groups. Feeding of all test chemicals during either initiation or postinitiation phases caused a significant reduction in the frequency of tongue carcinoma (68-88% reduction; P0.05). Dietary administration of these test chemicals also significantly decreased the bromodeoxyuridine labeling index of the tongue squamous epithelium (P0.05). In addition, polyamine levels in the oral mucosa were lowered in rats treated with 4-NQO and test chemicals when compared to those given 4-NQO alone. These results indicate that the flavonoids chalcone, 2-hydroxychalcone, and quercetin present in our daily foods have an inhibitory effect on oral carcinogenesis initiated with 4-NQO, and such a modifying effect may be related partly to the suppression of cell proliferation.

Pulsed doppler echocardiography is reported to be a reliable method for evaluating pulmonary hemodynamics in patients with cardiovascular diseases, but not with chronic obstructive pulmonary disease (COPD) because of the difficulty in obtaining an appropriate echo-window in such patients. We examined 23 patients with COPD by doppler echocardiography (Hewlett-Packard, HP77020CV) with a 2.5 MHz transducer via the subcostal approach in a supine position. The right side of the heart catheterization was performed simultaneously in sixteen of these patients. The remaining 7 patients received the same procedure within one week of the doppler echocardiography. Adequate ejection flow pattern from the right ventricle was obtained in all the patients. Significant negative linear relationships were found between pulmonary arterial pressure and acceleration time (r = -0.67) and ejection time (r = -0.52). These findings show that doppler echocardiography can be useful when evaluating pulmonary hemodynamics even in patients with COPD.

The chemopreventive effects of two xanthophylls, astaxanthin (AX) and canthaxanthin (CX) on oral carcinogenesis induced by 4-nitroquinoline 1-oxide (4-NQO) was investigated in male F344 rats. Rats were given 20 ppm of 4-NQO in their drinking water for 8 weeks to induce oral neoplasms or preneoplasms. Animals were fed diets containing 100 ppm AX or CX during the initiation or postinitiation phase of 4-NQO-induced oral carcinogenesis. The others contained the groups of rats treated with AX or CX alone and untreated. At the end of the study (week 32), the incidences of preneoplastic lesions and neoplasms in the oral cavity of rats treated with 4-NQO and AX or CX were significantly smaller than those of rats given 4-NQO alone (P0.001). In particular, no oral neoplasms developed in rats fed AX and CX during the 4-NQO exposure and in those given CX after the 4-NQO administration. Similarly, the incidences of oral preneoplastic lesions (hyperplasia and dysplasia) in rats treated with 4-NQO and AX or CX were significantly smaller than that of the 4-NQO-alone group (P0.05). In addition to such tumor inhibitory potential, dietary exposure of AX or CX decreased cell proliferation activity in the nonlesional squamous epithelium exposed to 4-NQO as revealed by measuring the silver-stained nucleolar organizer regions protein number/nucleus and 5'-bromodeoxyuridine-labeling index. Also, dietary AX and CX could reduce polyamine levels of oral mucosal tissues exposed to 4-NQO. These results indicate that AX and CX are possible chemopreventers for oral carcinogenesis, and such effects may be partly due to suppression of cell proliferation.

Large-scale coherent structures are known to play important roles in momentum transfer across turbulent boundary layers (Makita et al. 1989). The ‘turbulent bulge’ in the intermittent region is one of the structures related to the entrainment of momentum from a freestream into a turbulent boundary layer (Kovasznay et al. 1970). Reynolds stress must be measured around the large-scale coherent structure in order to obtain the magnitude of momentum transfer by it. It is not easy to detect the large-scale coherent structure by using conventional conditional sampling techniques, because the coherent structure appears randomly in time and space in a turbulent boundary layer and its intensity is not much larger than the background turbulence level. Recently, direct numerical simulations gave three-dimensional pictures of Reynolds stress distributions around the coherent structures (Robinson et al. 1990), but they could not completely clarify the behavior of the coherent structures in a turbulent boundary layer due to the limitations in their numerical calculation such as the employment of a periodic boundary condition.

The modifying effects of two natural products, curcumin and hesperidin, given during the initiation and postinitiation phases of oral carcinogenesis initiated with 4-nitroquinoline 1-oxide (4-NQO) were investigated in male F344 rats and compared with that of beta-carotene. At 6 weeks of age, rats were divided into experimental and control groups and fed the diet containing beta-carotene, hesperidin, or curcumin at a dose of 0.5 g/kg diet (500 ppm). At 7 weeks of age, all animals except those treated with each test chemical alone and control groups were given 4-NQO (20 ppm) in the drinking water for 8 weeks to induce oral cancer. Seven days after the 4-NQO exposure, groups of animals fed the diets containing test chemicals were switched to the basal diet and continued on this diet until the end of the study. Starting 1 week after the stop of 4-NQO exposure, the groups given 4-NQO and a basal diet were switched to the diets containing beta-carotene, hesperidin, and curcumin and maintained on these diets for 22 weeks. The other groups consisted of rats given 500 ppm beta-carotene, hesperidin, or curcumin alone or untreated rats. All animals were necropsied at the termination of the experiment (week 32). The incidences of tongue neoplasms and preneoplastic lesions, polyamine levels in the tongue tissue, and cell proliferation activity estimated by bromodeoxyuridine-labeling index and by morphometric analysis of silver-stained nucleolar organizer region proteins were compared among the groups. Feeding of curcumin and beta-carotene during the initiation and postinitiation phases and hesperidin at the initiation stage caused a significant reduction in the frequency of tongue carcinoma (41-91% reduction, P0.05) and the order of chemopreventive efficacy was curcuminbeta-carotenehesperidin. The incidences of oral preneoplasia in rats fed the diets mixed with these compounds were also decreased (P0.05). There were no such lesions in rats treated with test compounds alone or those in an untreated control group. Dietary administration of these compounds significantly decreased the labeling index of bromodeoxyuridine and the number and area of silver-stained nucleolar organizer region proteins per cell nucleus that are proliferation biomarkers, of the tongue squamous epithelium (P0.05). In addition, polyamine levels in the oral mucosa were lowered in rats treated with 4-NQO and three test compounds when compared to those give 4-NQO alone (P0.05).(ABSTRACT TRUNCATED AT 400 WORDS)

The initial stage of chemical-vapor- deposited (CVD) diamond growth on Si substrates has been investigated using transmission electron microscopy (TEM). The samples for TEM study have been observed from their lateral sides (side-view observation). The diamond particles are formed on Si protuberances fabricated by etching of substrate surface. These diamond particles nucleate randomly without respect to the orientation of the substrate surface. The top of the Si protuberance extends to the center of the diamond particle. High resolution TEM image shows that there is an amorphous layer underneath this particle and that this particle is surrounded by uneven {111} surfaces, where the multi-nucleation growth process can be observed.

Characteristic features of coherent motions were experimentally analyzed in a transition region of a two-dimensional jet with parabolic velocity distribution. The symmetrical or the anti-symmetrical vortex arrangement was weakly emphasized in the jet through an acoustic method. Hotwire measurements through a conditional sampling method were conducted point by point throughout the entire transition region. The resultant figures of the flow fields were compared with the pictures given by flow visualization by a conditional multi-smokewire method. The velocity vector maps demonstrated the characteristic features of the streamwise development of the jet’s macroscopic structure; the intensity of the vortical fluid motion, the streamwise growth of the jet’s width, and the meandering motion of the jet. The vorticity contour maps illustrated the differences in behaviour between the two modes of coherent vortices in the transition region with respect to the streamwise changes in the scale, configuration, peak intensity, and convection velocity of the coherent vortices. The present results suggested good possibility of controlling the jet structure by the acoustic method.

The streamwise evolution of three-dimensional structure of an artificially induced vortex was pursued by measuring velocity and vorticity fields through a simplified conditional sampling method. The artificial vortex developed downstream through the growth, the self-preserving and the decay stages. In the growth stage, the vortex grew up to have a horseshoe sculpture and the vorticity confined in it was increased downstream. The grown-up large-scale horseshoe vortex reached about 1.2δ in height, 1.0δ in width and 5.0δ in streamwise length. The vortex became more inclined forward and lost the ability of maintaining its self-similar construction in the decay stage. The convection velocity of the vortex’s head was 0.56 U ∞ in the foregoing two stages and was raised to 0.85 U ∞ in the decay stage.

We developed a new assay method for the evaluation of Le(Y) antigen expression on human peripheral T-lymphocytes using the monoclonal antibodies BM-1, CD4 and CD8 by two-color flow cytometry. Le(Y) antigen expressed on human peripheral T-lymphocytes was stained with fluorescein isothiocyanate (FITC)-labelled BM-1 (anti Le(Y) monoclonal antibody). Le(Y) positive cells were simultaneously stained with phycoerythrin (PE)-labelled CD4 or CD8, then analyzed by flow-cytometer. Coefficients of variations in this double staining assays were 4.2% for BM-1 in CD4 and 5.3% for BM-1 in CD8, respectively. In 124 healthy volunteers 0.2-13.1% of CD4 and 2.5-12.5% of CD8 positive cells were BM-1 positive. Lymphocytes from 200 patients with acute or chronic viral hepatitis showed marked increase in BM-1 expression of CD8 positive cells during the acute phase and exacerbation of the disease. Moreover, BM-1 expression of CD4 cells was positively related with the course of the chronic hepatitis and the prognosis of each patients. Therefore, this new assay using BM-1 and CD4, CD8 monoclonal antibodies would reflect progression of viral hepatitis and its related immunological condition.

A new type of active turbulence generator was designed. It can induce strong, homogeneous, and quasi-isotropic turbulence with a high turbulence Reynolds number in a laboratory wind tunnel. The resultant turbulence had intensity of more than 30% and an integral scale exceeding 200 mm just downstream of the generator. The maximum turbulence Reynolds number reached Re λ ≈ 600, which is about one order of magnitude larger than that of the grid turbulence with the same mesh Reynolds number, Re M. The energy spectrum of the strong turbulence had a clear inertial subrange spreading for more than two orders of magnitude in wave-number. The features of the spectrum are favorably comparable with those for the grid turbulence of Re M≈ 106

As a model of the coherent structure, an artificial horseshoe vortex was induced by injecting a pair of small pulsative jets into the bottom of a fully developed turbulent boundary layer from a flat plate beneath. After initial growth, the horseshoe vortex had a configuration similar to that of the natural coherent bulge and was broken up by a single manipulator plate installed parallel to the flow direction in the turbulent boundary layer. The ensemble-averaged data, conditionally sampled on the injection of the jets, gave velocity vector fields and shear stress contour maps around the nonmanipulated and manipulated vortices in each stage of their streamwise decay. The manipulated horseshoe vortex was sliced into two blocks that recombined in the downstream region, but with consequent suppression of the induced shear stress in the core of the manipulated horseshoe vortex. The "large-eddy breakup" method was verified as an efficient drag-reduction scheme.

The paper discusses the ultrasonic wave reflection at the interface between a 1–3 type composite transducer and water. It is shown that, because of the non-uniform ultrasonic displacement on the surface of the transducer, the reflection coefficient becomes a complex number and is not simply determined only by the acoustic impedance of the two materials. From the result, an equivalent circuit has been derived for the interface. The behaviour of the interface is substantially characterised by a parallel capacitance inserted between the two transmission lines representing the composite transducer and water.