Regression analysis of trends in mortality from hepatocellular carcinoma in Japan, 1972-2001

Background In Japan, higher mortality rates from hepatocellular carcinoma (HCC) have been observed than in any other industrialized country and the reported numbers of deaths due to HCC have increased significantly in recent years. We assessed whether there was a real increase in mortality from HCC and which factors contributed to the recent increasing trends of the number of deaths from HCC. Methods Poisson regression models were used to analyse panel data for the period 1972-2001. Results In both sexes, age-standardized mortality rates from HCC increased significantly over the past three decades. Among males the annual percentage increase in age-adjusted mortality rates was approximately 1-3% during the period 1972-96. On the other hand, female mortality trends were less clear. The estimated birth cohort effects suggested that there was a peak in the mortality risk among the cohorts born during the period 1927-36, which corresponded to those aged between 50-64 years during the period 1987-96. This was the period when a large increase of both age-specific mortality rates among older age groups and age-standardized mortality rates were observed particularly among males. Conclusions This study shows that an upward trend of mortality from HCC in Japan was primarily due to the effects among birth cohorts born around 1930, which are consistent with the pattern of past exposure to hepatitis C virus. The cohort effects have contributed to a large increase in mortality from HCC in recent years and the number of deaths from HCC is expected to increase by 2010-1

Characteristics of nonlinear terahertz-wave radiation generated by mid-infrared femtosecond pulse laser excitation

We report on efficient terahertz-wave generation in organic and inorganic crystals by nonlinear wavelength conversion approach using a 3.3 μm femtosecond pulse laser. Experimental results reveal the relation between pump power and terahertz-wave output power, which is proportional to the square of the pump power at the range of mega- to tera-watt cm−2 class even if the pump wavelength is different. Damage threshold of organic and inorganic crystals are recorded 0.6 and 18 tera-watt cm−2 by reducing several undesirable nonlinear optical effects using mid-infrared source

Dual-optical-comb spectroscopic ellipsometry

Spectroscopic ellipsometry is a means to investigate optical and dielectric material responses. Conventional spectroscopic ellipsometry has trade-offs between spectral accuracy, resolution, and measurement time. Polarization modulation has afforded poor performance due to its sensitivity to mechanical vibrational noise, thermal instability, and polarization wavelength dependency. We equip a spectroscopic ellipsometer with dual-optical-comb spectroscopy, viz. dual-optical-comb spectroscopic ellipsometry (DCSE). The DCSE directly and simultaneously obtains amplitude and phase information with ultra-high spectral precision that is beyond the conventional limit. This precision is due to the automatic time-sweeping acquisition of the interferogram using Fourier transform spectroscopy and optical combs with well-defined frequency. Ellipsometric evaluation without polarization modulation also enhances the stability and robustness of the system. In this study, we evaluate the DCSE of birefringent materials and thin films, which showed improved spectral accuracy and a resolution of up to 1.2x10-5 nm across a 5-10 THz spectral bandwidth without any mechanical movement.Comment: 30 pages, 4 figure

A Conversation Analysis Study of Speaking Rate Control by a Dysarthric Patient : A Case in which Dysarthria Improved in Conversation Continuity and Length of Utterances through Using a Pacing Board

ペーシングボードの使用により発話明瞭度が向上したdysarthria例に対して,会話分析の立場から「会話の伝達率」と「1発話の長さ」を検討し,主に以下の結果を得た.(1)ペーシングボード非使用時の会話伝達率は54.0%であったのに比し,使用時では98.1%と向上していた.(2)1発話の長さに関しては,モーラ数による比較ではペーシングボード非使用時の平均モーラ数は5.9,使用時は11.9であった.また平均文節数は非使用時1.4,使用時2.8と両指標とも約2倍に延長していた.以上の結果に基づいて,dysarthriaにおける発話速度調節訓練について会話分析から検討を加えた.Conversational transmissibility and length of utterances were studied in a　dysarthric patient who improved in intelligibility　because of use of a pacing board.The following results were obtained : (1)Conversational transmissibility was 54% when the pacing board was not used, whereas　transmissibility improved to 98.1 % when the board was used. (2) Comparison of the utterance length was made based on the number of mora, in which the average mora was 5.9 without use of the pacing board and 11.9 with use of the board. The number of average segments was 1.4 without　the board as opposed to 2.8 with the board. In both cases the indices increased by　nearly twofold when the pacing board was used. Based on these results, discussion　was held on the training of speaking rate control by the dysarthric speaker based on　conversation analysis

Dual-comb spectroscopic ellipsometry

Spectroscopic ellipsometry is a means of investigating optical and dielectric material responses. Conventional spectroscopic ellipsometry is subject to trade-offs between spectral accuracy, resolution, and measurement time. Polarization modulation has afforded poor performance because of its sensitivity to mechanical vibrational noise, thermal instability, and polarization-wavelength dependency. We combine spectroscopic ellipsometry with dual-comb spectroscopy, namely, dual-comb spectroscopic ellipsometry. Dual-comb spectroscopic ellipsometry (DCSE). DCSE directly and simultaneously obtains the ellipsometric parameters of the amplitude ratio and phase difference between s-polarized and p-polarized light signals with ultra-high spectral resolution and no polarization modulation, beyond the conventional limit. Ellipsometric evaluation without polarization modulation also enhances the stability and robustness of the system. In this study, we construct a polarization-modulation-free DCSE system with a spectral resolution of up to 1.2 × 10−5 nm throughout the spectral range of 1514–1595 nm and achieved an accuracy of 38.4 nm and a precision of 3.3 nm in the measurement of thin-film samples

Prevalence of and risk factors for postoperative complications after lower third molar extraction : A multicenter prospective observational study in Japan

Lower third molar extraction is the most common surgical treatment among routine dental and oral surgical procedures. while the surgical procedures for lower third molar extraction are well established, the difficulty of tooth extraction and the frequency of postoperative complications differ depending on the patient’s background. To establish a management protocol for the lower third molars, the prevalence of and risk factors for postoperative complications after lower third molar extraction were investigated in a large number of Japanese patients in a multicenter prospective study. During 6 consecutive months in 2020, 1826 lower third molar extractions were performed at the 20 participating institutions. The medical records of the patients were reviewed, and relevant data were extracted. The prevalence of and risk factors for postoperative complications were analyzed. The prevalence of postoperative complications after lower third molar extraction was 10.0%. Multivariate analysis indicated that age (≤32 vs >32, odds ratio [OR]: 1.428, 95% confidence interval [95% CI]: 1.040–1.962, P < .05), the radiographic anatomical relationship between the tooth roots and mandibular canal (overlapping of the roots and canal vs no close anatomical relationship between the roots and the superior border of the canal, OR: 2.078, 95% CI: 1.333–3.238, P < .01; overlapping of the roots and canal vs roots impinging on the superior border of the canal, OR: 1.599, 95% CI: 1.050–2.435, P < .05), and impaction depth according to the Pell and Gregory classification (position C vs position A, OR: 3.7622, 95% CI: 2.079–6.310, P < .001; position C vs position B, OR: 2.574, 95% CI: 1.574–4.210, P < .001) are significant independent risk factors for postoperative complications after lower third molar extraction. These results suggested that higher age and a deeply impacted tooth might be significant independent risk factors for postoperative complications after lower third molar extraction

Scan-less confocal phase imaging based on dual-comb microscopy

Confocal laser microscopy (CLM) is a powerful tool in life science research and industrial inspection because it offers two-dimensional optical sectioning or three-dimensional imaging capability with micrometer depth selectivity. Furthermore, scan-less imaging modality enables rapid image acquisition and high robustness against surrounding external disturbances in CLM. However, the objects to be measured must be reflective, absorptive, scattering, or fluorescent because the image contrast is given by the optical intensity. If a new image contrast can be provided by the optical phase, scan-less CLMcan be further applied for transparent non-fluorescent objects or reflective objects with nanometer unevenness by providing information on refractive index, optical thickness, or geometrical shape. Here, we report scan-less confocal dual-comb microscopy offering a phase image in addition to an amplitude image with depth selectivity by using an optical frequency comb as an optical carrier of amplitude and phase with discrete ultra-multichannels. Our technique encodes confocal amplitude and phase images of a sample onto a series of discrete modes in the optical frequency comb with well-defined amplitude and phase to establish a one-to-one correspondence between image pixels and comb modes. The technique then decodes these images from comb modes with amplitude and phase. We demonstrate confocal phase imaging with milliradian phase resolution under micrometer depth selectivity on the millisecond timescale. As a proof of concept, we demonstrate the quantitative phase imaging of standing culture fixed cells and the surface topography of nanometer-scale step structures. Our technique for confocal phase imaging will find applications in three-dimensional visualization of stacked living cells in culture and nanometer surface topography of semiconductor objects

Identity of the elusive IgM Fc receptor (FcμR) in humans

Although Fc receptors (FcRs) for switched immunoglobulin (Ig) isotypes have been extensively characterized, FcR for IgM (FcμR) has defied identification. By retroviral expression and functional cloning, we have identified a complementary DNA (cDNA) encoding a bona fide FcμR in human B-lineage cDNA libraries. FcμR is defined as a transmembrane sialoglycoprotein of ∼60 kD, which contains an extracellular Ig-like domain homologous to two other IgM-binding receptors (polymeric Ig receptor and Fcα/μR) but exhibits an exclusive Fcμ-binding specificity. The cytoplasmic tail of FcμR contains conserved Ser and Tyr residues, but none of the Tyr residues match the immunoreceptor tyrosine-based activation, inhibitory, or switch motifs. Unlike other FcRs, the major cell types expressing FcμR are adaptive immune cells, including B and T lymphocytes. After antigen-receptor ligation or phorbol myristate acetate stimulation, FcμR expression was up-regulated on B cells but was down-modulated on T cells, suggesting differential regulation of FcμR expression during B and T cell activation. Although this receptor was initially designated as Fas apoptotic inhibitory molecule 3, or TOSO, our results indicate that FcμR per se has no inhibitory activity in Fas-mediated apoptosis and that such inhibition is only achieved when anti-Fas antibody of an IgM but not IgG isotype is used for inducing apoptosis