We demonstrate the (111)-oriented Ge-on-Insulator (GOI) formed by Ge epitaxial growth on a Si(111) and the layer transfer technique. The two-step growth manner, involving low-temperature growth of a ...thin Ge layer and subsequent high-temperature growth of a thick Ge layer, enables us to obtain high-quality tensile-strained epitaxial Ge(111) on Si(111). It is found that the strain amount straongly depends on the growth temperatures and we find an optimal growth temperature. We also developed a chemical mechanical polishing (CMP) method modified for Ge, offering the ultra-smooth Ge(111) surface. The polished epitaxial Ge is bonded on a SiO2/Si, followed by the selective etching of Si and the final CMP of Ge. As a result, we achieve the high-quality 200-nm-thick tensile-strained Ge(111)-OI with an ultra-smooth surface, on which, furthermore, we demonstrate the growth of an epitaxial metallic silicide for the metal source/drain in spintronic devices as well as advanced Ge channel devices.
•A high-quality Ge layer is epitaxially grown on a Si(111) by two-step growth manner.•Ultra-smooth Ge surface is obtained with modified chemical mechanical polishing.•Epitaxially grown Ge is transferred onto a SiO2/Si.•High-quality tensile-strained Ge-on-Insulator with (111) orientation is obtained.
The long-term comprehensive prognosis of chronic hepatitis C after direct-acting antiviral (DAA) therapy is unclear. This study aimed to investigate the prognosis and incidence of immunological and ...oncological complications after DAA therapy.
The study included a total of 1461 patients who received DAA therapy in our university hospital and affiliated hospitals between September 3, 2014 and September 30, 2018.
The incidence rates of total malignancies in overall or female patients after DAA therapy were significantly greater than expected in the corresponding general population. The same was true for lung malignancies. Predictive risk factors associated with the occurrence and recurrence of hepatic malignancies after DAA therapy in patients with sustained virological response were cirrhosis and insulin use, protein induced by vitamin K absence or antagonist-II level, and albumin-bilirubin score, respectively. Eight (0.5%) patients were diagnosed with autoimmune diseases after starting DAA therapy. Importantly, the attending physician considered a possible causal relationship between DAA therapy and these autoimmune diseases in five cases (four rheumatoid arthritis and one membranoproliferative glomerulonephritis). The 5-year overall survival rate was 91.6%. The most frequent primary cause of death was malignancy in 41 (60.2%) patients, including 25 with hepatic malignancies. Lung and colorectal cancers were the next most common.
Given that the incidence of total and lung cancers might increase and DAA-related autoimmune diseases might emerge after DAA therapy, we should be alert for the development of these diseases as well as hepatic malignancies.
We examine a peak-to-average power ratio (PAPR) reduction effect in an optical fiber link using a fractional Fourier transform (FrFT). Fractional OFDM (FrOFDM) based on FrFT in place of discrete ...Fourier transform is a multiplexing approach that can balance the pros and cons of subcarriers in the time and frequency domains while keeping its orthogonal condition. A careful investigation of the PAPR behavior of a FrOFDM signal confirms that its PAPR can be minimized at a point where a Nyquist pulse train is formed by a time-lens effect. With emphasis on this low-PAPR characteristic of a Nyquist pulse train, the signal quality degradation owing to fiber nonlinearity can be mitigated. A 1.0-dB signal quality improvement after propagation in a dispersion-compensated fiber link is demonstrated in a simulation for a 12×10-Gbaud∕s 16 QAM FrOFDM signal in comparison with that of a conventional OFDM.
•A PAPR reduction effect using all-optical fractional OFDM is examined.•A Fractional OFDM signal is converted to a Nyquist pulse train by a time-lens effect.•PAPR is minimized at a point where a Nyquist pulse train is formed.•A controlling of PAPR can suppress nonlinear signal impairments in a fiber.
BACKGROUND The transcription factor, octamer-binding transcription factor 4 (OCT4)/POU5F1, is expressed in embryonic stem cells, germ cells and some types of adult stem cells. Human OCT4 encodes two ...isoforms, OCT4A and OCT4B. While OCT4A plays a crucial role in the maintenance of stem cell properties, including pluripotency, whereas OCT4B does not. We previously reported that human myometrium contains side population cells (myoSP) with a Hoechst 33 342 low-fluorescent profile. These cells exhibit phenotypic and functional characteristics of myometrial stem cells. The objective of this study was to investigate the comparative expression of OCT4 in the stem/progenitor cell population of the human myometrium. METHODS Human myometrial tissue samples were collected from 18 consenting patients who underwent hysterectomy because of benign gynecological diseases. The resultant isolated or cultured myometrial cells and isolated myoSP were subjected to semi-quantitative and real-time RT–PCR analyses, immunoblot analyses and immunohistochemistry. RESULTS RT–PCR and immunoblot analyses revealed that OCT4 mRNA and OCT4 protein were detectable in some (but not all) myometrial samples. Immunohistochemistry showed that OCT4 protein was confined to the nuclei of relatively few cells in myometrial tissues expressing OCT4 mRNA. OCT4 and OCT4A transcripts, but not those of OCT4B, were more abundant in myoSP than in non-myoSP, as determined by real-time and semi-quantitative RT–PCR analyses. CONCLUSIONS Relatively few myometrial cells express OCT4 protein. OCT4 mRNA, in particular OCT4A mRNA, is up-regulated in myoSP that have been reported to exhibit stem cell-like properties. Taken together, the present results indicate that the myoSP population is enriched in OCT4 mRNA.
In recent years a number of chemistry-climate models have been developed with an emphasis on the stratosphere. Such models cover a wide range of time scales of integration and vary considerably in ...complexity. The results of specific diagnostics are here analysed to examine the differences amongst individual models and observations, to assess the consistency of model predictions, with a particular focus on polar ozone. For example, many models indicate a significant cold bias in high latitudes, the "cold pole problem", particularly in the southern hemisphere during winter and spring. This is related to wave propagation from the troposphere which can be improved by improving model horizontal resolution and with the use of non-orographic gravity wave drag. As a result of the widely differing modelled polar temperatures, different amounts of polar stratospheric clouds are simulated which in turn result in varying ozone values in the models. The results are also compared to determine the possible future behaviour of ozone, with an emphasis on the polar regions and mid-latitudes. All models predict eventual ozone recovery, but give a range of results concerning its timing and extent. Differences in the simulation of gravity waves and planetary waves as well as model resolution are likely major sources of uncertainty for this issue. In the Antarctic, the ozone hole has probably reached almost its deepest although the vertical and horizontal extent of depletion may increase slightly further over the next few years. According to the model results, Antarctic ozone recovery could begin any year within the range 2001 to 2008. The limited number of models which have been integrated sufficiently far indicate that full recovery of ozone to 1980 levels may not occur in the Antarctic until about the year 2050. For the Arctic, most models indicate that small ozone losses may continue for a few more years and that recovery could begin any year within the range 2004 to 2019. The start of ozone recovery in the Arctic is therefore expected to appear later than in the Antarctic. Further, interannual variability will tend to mask the signal for longer than in the Antarctic, delaying still further the date at which ozone recovery may be said to have started. Because of this inherent variability of the system, the decadal evolution of Arctic ozone will not necessarily be a direct response to external forcing.
Abstract Background The objective of this study was to examine the clinical outcomes of immediate breast reconstruction using perforator flaps from different donor sites, and to characterize the ...trends among these flaps. Methods We retrospectively reviewed 136 consecutive patients who underwent immediate breast reconstruction using free flaps after skin-sparing mastectomy (SSM) or nipple-sparing mastectomy (NSM). The whole breast was pathologically analyzed in 5-mm sections. Breast reconstruction was performed using the deep inferior epigastric perforator (DIEP) flap, gluteal artery perforator (GAP) flap, and posterior medial thigh perforator (PMTP) flap. Patient characteristics were compared among donor sites. Results NSM was converted to SSM because of intraoperative subareolar tumor positivity in 7 of 107 patients. Eleven patients had positive margins in permanent sections. All but one patient had a positive horizontal margin in the peripheral direction. The 5-year recurrence-free survival rate was 91.9%. The locoregional recurrence rate was 5.1% with a mean follow-up observation period of 75 months. DEIP, GAP, and PMTP flaps were used in 64 (47.1%), 38 (27.9%), and 34 (25.0%) patients, retrospectively. DIEP flaps were used in older patients and those with a higher body mass index. GAP flaps were used in younger patients. DIEP and GAP flaps were used for larger breasts, and PMTP flaps for smaller breasts. Conclusion NSM or SSM with immediate perforator flap breast reconstruction is an oncologically acceptable surgical option. We believe that age, desire to have children, body mass index, and excised breast volume are valuable factors for selecting the optimal donor site.
The aim of this retrospective multicenter study was to evaluate the differences in the timing for starting systemic therapies as the first-line treatment for hepatocellular carcinoma (HCC).
A total ...of 375 patients with HCC treated with sorafenib from May 2009 to March 2018 and 56 patients treated with lenvatinib from March 2018 to November 2018 at our affiliated hospitals were included in this study.
The median ages of the sorafenib and lenvatinib groups were 71.0 (interquartile range IQR: 64.0-77.0) and 73.5 (IQR: 68.0 -80.0) years old, and 300 (80.0%) and 42 (75.0%) patients were men, respectively. The Barcelona Clinic Liver Cancer stage was early, intermediate and advanced in 39 patients (10.4%), 133 patients (35.5%) and 203 patients (54.1%) in the sorafenib group and 1 patient (1.8%), 17 patients (30.4%) and 38 patients (67.9%) in the lenvatinib group, respectively. In the analysis of intermediate HCC, patients who satisfied the criteria of TACE failure/refractoriness (P=0.017), those with ALBI grade 1 (P=0.040), and those with a serum AFP level < 200 ng/ml (P=0.027) were found more frequently in the lenvatinib group than in the sorafenib group, with statistical significance. The objective response rate (ORR) of lenvatinib was 34.8% in the overall patients and 46.7% in the intermediate-stage HCC patients, which was significantly higher than sorafenib (P=0.001, P=0.017).
The emergence of lenvatinib has encouraged physicians to start systemic chemotherapy earlier in intermediatestage HCC patients.
We experimentally demonstrate a compact and tunable four-wave-mixing-based wavelength converter using a Bi/sub 2/O/sub 3/-based nonlinear fiber (Bi-NLF). An only 40-cm-long Bi-NLF is used as a ...nonlinear optical medium for wavelength conversion of a 40-Gb/s nonreturn-to-zero (NRZ) signal with no additional stimulated Brillouin scattering (SBS) suppression scheme. The Bi-NLF used in this experiment has an extremely high SBS threshold owing to both its short length and relatively low Brillouin gain. The 40-cm Bi-NLF is fusion-spliced to standard single-mode fibers and its nonlinearity is measured to be /spl sim/1100 W/sup -1//spl middot/km/sup -1/. Error-free wavelength conversion over a 10-nm bandwidth at a 40-Gb/s NRZ data rate is readily achieved with a pure continuous-wave pump.
We verified the insertion effect of a cyclic prefix (CP) in an all-optical fractional orthogonal frequency division multiplexing (FrOFDM) system. CP is an essential technique for reducing ...inter-channel interference in conventional OFDM. Because a FrOFDM signal is generated by a fractional Fourier transform, which is a generalization of the Fourier transform, a CP is also effective for a FrOFDM signal. The measured bit error rate of a 4×10 Gbit/s DBPSK all-optical FrOFDM system showed that the CP improves the signal quality even if the performance of the time gate is insufficient.
•A cyclic prefix insertion for all-optical FrOFDM is experimentally demonstrated.•A cyclic prefix insertion is realized in an optical domain.•A cyclic prefix can reduce the ICI of the detected all-optical FrOFDM signal.•An effect of cyclic prefix insertion is quantified in a simulation.
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