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We carried out an experimental comparison study of the two most established optoelectronic emitters for continuous-wave (cw) terahertz generation: a uni-traveling-carrier photodiode (UTC-PD) and a pin-photodiode (PIN-PD). Both diodes are commercially available and feature a similar package (fiber-pigtailed housings with a hyper-hemispherical silicon lens). We measured the terahertz output as a function of optical illumination power and bias voltage from 50 GHz up to 1 THz, using a precisely calibrated terahertz power detector. We found that both emitters were comparable in their spectral power under the operating conditions specified by the manufacturers. While the PIN-PD turned out to be more robust against varying operating parameters, the UTC-PD showed no saturation of the emitted terahertz power even for 50 mW optical input power. In addition, we compared the terahertz transmission and infrared (IR) blocking ratio of four different filter materials. These filters are a prerequisite for correct measurements of the absolute terahertz power with thermal detectors.

In order to clarify the availability of a soil-bag (breastwork) method for reducing response amplitude on the ground, two types of vibration tests were performed. In addition to the tests, simple shear tests to determine material properties were conducted. Through a parametric study on the vibration tests, the effective information for estimating dynamic properties such as elastic modulus, response amplification and complex features in the time history can be obtained. The damping factors are estimated based on the resonance curves and those are the range from 8% to 11%. The reason for the reduced occurrence is discussed. The grain size of the sands considerably affects the elastic modulus and the damping factor. While the amplification distribution along the heights and the amplitude spectrum ratios for the wide frequency range are simple, the dynamic behavior exhibits complexity. The 3D-FEM model is useful to reproduce the test results though through try and error.

The high design luminosity of the SuperKEKB electron-positron collider will result in challenging levels of beam-induced backgro\ unds in the interaction region. Understanding and mitigating these backgrounds is critical to the success of the Belle~II experi\ ment. We report on the first background measurements performed after roll-in of the Belle II detector, a period known as SuperKE\ KB Phase 2, utilizing both the BEAST II system of dedicated background detectors and the Belle II detector itself. We also repor\ t on first revisions to the background simulation made in response to our findings. Backgrounds measured include contributions f\ rom synchrotron radiation, beam-gas, Touschek, and injection backgrounds. At the end of Phase 2, single-beam backgrounds origina\ ting from the 4 GeV positron Low Energy Ring (LER) agree reasonably well with simulation, while backgrounds from the 7 GeV elect\ ron High Energy Ring (HER) are approximately one order of magnitude higher than simulation. We extrapolate these backgrounds for\ ward and conclude it is safe to install the Belle II vertex detector., Comment: 22 Pages, 33 figures

Objective: To clarify whether there are any muscle synergy changes in individuals with knee osteoarthritis, and to determine whether muscle synergy analysis could be applied to other musculoskeletal diseases. Methods: Subjects in this study included 11 young controls (YC), 10 elderly controls (EC), and 10 knee osteoarthritis patients (KOA). Gait was assessed on a split-belt treadmill at 3 km/h. A non-negative matrix factorization (NNMF) was applied to the electromyogram data matrix to extract muscle synergies. To assess the similarity of each module, we performed the NNMF analysis assuming four modules for all of the participants. Further, we calculated joint angles to compare the kinematic data between the module groups. Results: The number of muscle modules was significantly lower in the EC (2–3) and KOA (2–3) groups than in the YC group (3–4), which reflects the merging of late swing and early stance modules. The EC and KOA groups also showed greater knee flexion angles in the early stance phase. Contrarily, by focusing on the module structure, we found that the merging of early and late stance modules is characteristic in KOA. Conclusion: The lower number of modules in the EC and KOA groups was due to the muscle co-contraction with increased knee flexion angle. Contrarily, the merging of early and late stance modules are modular structures specific to KOA and may be biomarkers for detecting KOA. Significance: Describing the changes in multiple muscle control associated with musculoskeletal degeneration can serve as a fundamental biomarker in joint disease.

A novel THz-wave autocorrelator consisting of an optical delay line and high-speed photodiodes was proposed for the measurement of optical waveforms with a high rate of repetition. In this system, the waveform is delayed at the optical domain and correlated at the THz domain. Experimental results show clear autocorrelations of 100, 200 and 300 GHz sinusoidal waveforms which indicate the feasibility of the proposed method.

A Fermi-level managed barrier (FMB) diode was used for the heterodyne detection of terahertz waves for the first time. A quasi-optical module integrating an FMB diode and a broadband trans-impedance amplifier exhibited an intermediate frequency bandwidth of 11 GHz. A very low noise-equivalent-power of 1.1 × 10−18 W/Hz was achieved at ∼300 GHz with a very low local oscillator power of 6 × 10−6 W.

We provide the first-ever direct comparison of the terahertz (THz) output of fiber-coupled UTC- and PIN-based continuous-wave emitters. As both emitters are characterized in the same setup, the observed differences can be traced back to the diode structure itself. We find large differences for frequencies below 350 GHz, where each device excels in a certain spectral range. Between 350 GHz and 1 THz, both emitters achieve a comparable THz output.

An analytical method for quantifying zearalenone (ZEA) in pet foods using a liquid chromatograph-atmospheric pressure chemical ionization-mass spectrometer (LC-APCI-MS) was developed, and an inter-laboratory study was conducted. ZEA was extracted from pet food samples with aqueous acetonitrile. The extract was purified using a multifunctional column, MultiSep 226 Aflazon+, and analysed with LC-APCI-MS. The limit of quantification of ZEA by this method was estimated to be 0.2 mg/kg for dry and semi-dry pet foods, and 0.1 mg/kg for wet pet food. The calibration curve of ZEA for this method showed linearity in the range of 0.1-10 ng of ZEA (0.01-1.0 µg/ml, 0.04-4.0 mg/kg matrix). The mean recoveries, repeatabilities, reproducibilities, and the HorRats for ZEA from the inter-laboratory validation study were 99.0-102%, 2.2-3.0%, 5.6-6.6%, and 0.33-0.36, respectively.

Fundamental science, as well as all communications and navigation systems, are heavily reliant on the phase, timing, and synchronization provided by low-noise and agile frequency sources. Although research into varied photonic and electronic schemes have strived to improve upon the spectral purity of microwave and millimeter-wave signals, the reliance on conventional electronic synthesis for tuning has resulted in limited progress in broadband sources. Using a digital-photonic synthesizer architecture that derives its time-base from a high-stability optical reference cavity, we generate frequency-agile and wideband microwave signals with exceptional dynamic range and with a fractional frequency instability of 1 × 10−15 at 1 s. The presented architecture demonstrates digitally controlled, user defined and broadband frequency tuning from RF to 100 GHz with orders-of-magnitude improvement in noise performance over room-temperature electronic wide-bandwidth synthesis schemes.

Summary What is known and objective The pharmacokinetic–pharmacodynamic parameter that best predicts the efficacy of vancomycin is the ratio of the area under the concentration versus time curve (AUC) to the minimum inhibitory concentration (MIC). A 24-h AUC (AUC24)/MIC ratio ≥ 400 was recommended in an American consensus review, but vancomycin treatment occasionally fails despite maintenance of AUC24/MIC ≥ 400. We evaluated the association between clinical efficacy of vancomycin and two novel pharmacokinetic parameters, the ‘area under the trough level’ (AUTL) and the ‘area above the trough level’ (AATL), in hospitalized elderly patients with methicillin-resistant Staphylococcus aureus (MRSA) pneumonia. Methods The subjects were hospitalized elderly patients who were administered vancomycin for treatment of MRSA pneumonia between 2006 and 2012 at Sasebo Chuo Hospital (Nagasaki, Japan). Pharmacokinetic parameters of vancomycin were estimated for each patient by Bayesian analysis using population pharmacokinetic parameters for Japanese patients. Based on the patient-specific parameters thus obtained, AUC24 values were calculated as the vancomycin dosage divided by vancomycin clearance. AUTL was calculated as the trough serum concentration multiplied by 24 h, whereas AATL was calculated by subtracting AUTL from AUC24. Results and discussion Logistic regression analysis demonstrated that efficacy of vancomycin was more strongly associated with AUTL than AUC24. The optimal cut-off value of AUTL was 331 μg∙h/mL, which means that the optimal cut-off value of the trough serum concentration was 13·8 μg/mL. What is new and conclusion Efficacy of vancomycin was associated with AUTL, a novel pharmacokinetic parameter. Determining the target AUTL or trough concentration may enhance the efficacy of vancomycin therapy in elderly patients with MRSA pneumonia. Given that nephrotoxicity may increase with a Ctrough in excess of 15 μg/mL, this level should ideally not be exceeded.

A dual-polarization terahertz imaging system using a noise source which has frequency components between 0.075 THz and 0.11 THz has been newly developed for food inspection. The imaging system can take horizontal and vertical polarization images independently and simultaneously with a spatial resolution of better than 4 mm and a high data acquisition speed of 10 lines data (1,200 pixels) /msec. These characteristics of the imaging system fulfill industrial requirements for inspection of foods conveyed at a velocity of higher than 20 m/min.

An analytical method to determine fumonisin B1 (FB1), B2 (FB2) and B3 (FB3) in pet foods using a liquid chromatography-electrospray ionization-mass spectrometer (LC-ESI-MS) was developed, and an inter-laboratory study was conducted in eleven laboratories. FB1, FB2 and FB3 were extracted with aqueous acetonitrile. The extract was purified by a multifunctional column, MultiSep 211 Fum, and analysed by LC-ESI-MS. The limit of quantification of fumonisins was estimated to be 0.2 mg/kg for dry and semi-dry pet foods, and 0.1 mg/kg for wet pet food. The calibration curve showed linearity in the range of 0.1-5 ng of fumonisins (0.02-1.0 μg/ml). The values of the mean recovery for FB1 at 0.1-1.0 mg/kg were 93.3-107% and of the relative standard deviation less than 7.9%. These values were 87.3-102 and 8.6% for FB2 and 90.8-102 and 8.6% for FB3, respectively. The mean recovery, repeatability, reproducibility and the Horwitz ratio for FB1 from the inter-laboratory validation study were 92.9-98.9%, 2.6-4.6%, 6.8-10% and 0.41-0.54, respectively. The values for FB2 were 91.5-94.7%, 2.7-5.9%, 6.8-8.9% and 0.33-0.55, respectively, and the values for FB3 were 90.1-94.3%, 3.3-5.9%, 7.3-9.5% and 0.44-0.57, respectively.

A novel Fermi-level managed barrier diode has been developed for achieving broadband and low-noise terahertz-wave detection. The fabricated quasi-optical module detected signals at frequencies from 200 GHz to 1 THz. The typical voltage sensitivity was 1020 V/W, and the current sensitivity for a 50 Ω load was 4.5 A/W at 300 GHz for a zero-biased condition. Square-law detection with good linearity was demonstrated at 300 GHz with an output current density exceeding 103 A/cm2.

Abstrac t—In this study, we propose a Sliding Mode Control (SMC) with a state predictor for time delay control systems. Time delay is a factor that causes instability in systems, and SMC is weakened by time delay. Therefore, we use a state predictor with SMC. State predictors are easily designed, and are suitable in combination with SMCs using the state of the plant as a controller. We have successfully realized control using a SMC with a state predictor for the plant with the time delay. In addition, we have confirmed the robustness of the proposed method. The proposed method shows the effective result compared with the conventional method in the simulation.

We have grown rare-earth doped CaFe 2 As 2 single crystals and characterized their normal and superconducting properties. Temperature dependence of resistivity and its absolute value suggest good metallic conduction, suppressing antiferromagnetic (AF) transition in the undoped sample. Hall coefficient shows little temperature dependence, consistent with the suppression AF state. Superconducting transitions characterized by resistivity drops in magnetic fields for both parallel to c -axis and ab -plane are reasonably sharp with a weak anisotropy parameter ∼1.75. Despite these observations, average critical current density estimated from the bulk magnetization is orders of magnitude smaller than other typical iron-based superconductors. Magneto-optical imaging confirms very inhomogeneous superconducting state.

We experimentally verify that the low external responsivity of nanostructured asymmetric-dual-grating-gate high-electron-mobility transistors (A-DGG HEMTs) as plasmonic terahertz detectors developed so far is attributed to their low external coupling efficiency. We separately demonstrate (1) 4-fold enhancement of the efficiency by an array of series-connected 4×1 detectors due to the increase in the effective active area and (2) 6-fold enhancement by the silicon-lens integration due to the better focusing inside the silicon lens. Those preliminary results indicate a possibility of enhancing external responsivities of A-DGG HEMTs up to their intrinsic values.

A 450mm CMP tool is installed, calibrated, and process qualified on oxide CMP process before the STI, W, and Cu processes can be evaluated. With the new multi-area polishing heads, the oxide removal rates ∼ 1800 A/min and the WIWNU% (3a) ≤ 8% within the same polish table can be achieved with a fumed-silica based slurry on a traditional IC pad as the first trial. A small baseline of wafer run is performed on each process table and the WTW (wafer-to-wafer) and HTH (head-to-head) removal rate variations are then calculated. In each polish table, sufficient WTW removal rate variation were obtained and current best WTWNU(3σ) was 1.1%. The tuning of removal rates on each Head/Polish table can be achieved with the manufacturer's advanced technologies, based on the signals and parameters pulled from the tool during processing. These signals and parameters allow process engineers to check if the wafers are processed at the similar conditions on the polishing pads. Polish behaviors of different silica based slurries, fumed & colloidal silica, on the same polishing pad are compared. More process results on STI application will be shown in the final paper, mainly on 450mm blanket monitor wafers.

Two models of carcinogenesis have recently been proposed for ovarian cancer based on the differences in the mechanism of carcinogenesis. Low-grade serous carcinoma and mucinous carcinoma are classified as type I, and high-grade serous carcinoma and high-grade endometrioid carcinoma are classified as type II ovarian cancers. Low-and high-grade serous carcinomas were reported to have independent pathologies based on their morphological characteristics, molecular mechanism of histogenesis, and clinical features. Serial activation of the components of the mitogen activated protein kinase (MAPK) signaling pathway was observed in low-grade serous carcinomas resistant to existing anticancer drugs, and the efficacy of MEK inhibitors targeting these signals has been demonstrated. The morphology- and molecular biology-based elucidation of the pathology of ovarian cancers might lead to the implementation of personalized treatment through molecular-targeted therapy.

Summary What is known and Objective: Various factors have been reported to be associated with the duration of regulatory review of new drug applications (NDAs). We investigated potential links between the review times in Japan and the attributes of NDAs, the regulatory agency and pharmaceutical companies. Methods: We analysed new drugs approved in 2000–2009 in Japan using a proprietary database collected through annual surveys to pharmaceutical companies. Regression models in which individual firms were treated as either a fixed effect or a random effect were applied to examine factors associated with the overall review time and the duration of each step of the review. Results and Discussion: The fixed effect model analysis using variations within each firm indicated that new molecular entities that were submitted to the Pharmaceuticals and Medical Devices Agency (PMDA), priority reviews and pre-NDA consultations were associated with a shorter overall review time, whereas additional studies during the review resulted in a longer review. In the random effect model analysis using both within- and between-firm variations, use of end-of-phase 2 consultations and foreign clinical data also had negative coefficients, suggesting the effect of these two vary among firms. Analysis of each step of the review process revealed NDAs reviewed by the Committee on Drugs under the Ministry of Health, Labour and Welfare, and the number of NDAs assigned to a review team were significantly linked with their duration, whereas consultation services and the number of reviewers had no relation. What is new and Conclusion: Factors associated with each step of the review process as well as the differences in attributes and strategies among pharmaceutical companies should be considered to further improve the speed, quality and efficiency of the regulatory review.

The pinning parameters for numerical calculation based on the flux creep-flow model are determined by using genetic algorithm (GA), which has been applied to many practical determination for parameters. Several estimation functions which describe the distance between the experimental and calculated results by GA were proposed, and the difference between the results were calculated. It is found that the pinning parameters of the flux creep-flow model are successfully deduced by GA. The difference between the calculated and experimental results and the calculation time are found to be largely depended on the estimation functions., Proceedings of the 24th International Symposium on Superconductivity (ISS 2011), October 24-26, 2011, Tokyo, Japan