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Abstract The present paper provides an overview of an online module for formative assessment of summary writing skills for second language (L2) introductory academic writing instruction in Japan and presents initial empirical results on how Japanese undergraduate students’ summary writing performance changed with a series of automated summary content feedback delivered in the module. A key feature of this module was the provision of fine-grained feedback delivered as scaffolding during revisions in terms of two key aspects of summary content: main idea representation and paraphrasing. Participants were 64 Japanese undergraduate engineering majors in introductory academic writing courses at a private university in Tokyo. The students completed two summary writing tasks provided through the online module. Results of a multivariate analysis of variance showed significant improvement of the content analytic score on revision on the initial summary task, and that this improved performance level was retained on a transfer task. The language use analytic score also improved significantly on the transfer task. Detailed analyses of learner-produced summaries based on descriptive statistics further suggested that the learners made substantively meaningful changes concerning main idea coverage and verbatim copying of the source text while still meeting the length requirement, although the results differed somewhat across the source texts assigned. Despite some study limitations, these results provide initial support for immediate content feedback provision for the development of basic summary writing skills.

Pancreatic lipase catalyzes the cleavage of triacylglycerols at the oil–water interface, and is known as the dominant determiner of dietary fat digestion. Reducing dietary fat digestion and absorption by modulating the activity of pancreatic lipase has become a favorable strategy to tackle obesity. Orlistat is, at present, the only pancreatic lipase inhibitor approved for the treatment of obesity; however, an array of gastrointestinal adverse effects associated with orlistat limits its tolerability. As a safe alternative to orlistat, a number of natural product-derived compounds with varying degrees of pancreatic lipase inhibitory activity have been reported. We herein reported that bioactivity-guided fractionation of sesame meal led to the identification of free linoleic acid and oleic acid as potent inhibitors of porcine pancreatic lipase in vitro with an IC50 of 23.1 µg/mL (82.4 µM) and 11.7 µg/mL (41.4 µM), respectively. In rats, a single oral dose of the mixture of these fatty acids significantly suppressed the elevation of blood triacylglycerol level following fat intake. These results substantiate the role of free linoleic acid and oleic acid as a novel class of natural product-derived functional molecules that act as pancreatic lipase inhibitors, and their potential for healthy, routine-based weight management.

Abstract Background Although Helicobacter-induced gastric inflammation is the major predisposing factor for gastric carcinogenesis, the precise mechanism by which chronic gastritis causes gastric cancer remains unclear. Intestinal and spasmolytic polypeptide-expressing metaplasia (SPEM) is considered as precancerous lesions, changes in epithelial tissue stem/progenitor cells after chronic inflammation has not been clarified yet. In this study, we utilized three-dimensional gastric epithelial cell culture systems that could form organoids, mimicking gastric epithelial layer, and characterized the changes in epithelial cells after chronic Helicobacter felis infection. Methods We used three mice model; 1) long-term H. felis infection, 2) H. felis eradication, and 3) MNU chemical carcinogenesis model. We performed cRNA microarray analysis after organoid culture, and analyzed the effects of chronic gastric inflammation on tissue stem cells, by the size of organoid, mRNA expression profile and immunohistochemical analysis. Results The number of organoids cultured from gastric epithelial cells was significantly higher in organoids isolated from H. felis-infected mice compared with those from uninfected gastric mucosa. Based on the mRNA expression profile, we found that possible stem cell markers such as Cd44, Dclk1, and genes associated with the intestinal phenotype, such as Villin, were increased in organoids isolated from H. felis-infected mucosa compared with the control. The upregulation of these genes were cancelled after H. felis eradication. In a xenograft model, tumors were generated only from organoids cultured from carcinogen-treated gastric mucosa, not from H. felis infected mucosa or control organoids. Conclusions Our results suggested that, as a possible mechanism of gastric carcinogenesis, chronic inflammation induced by H. felis infection increased the number of tissue stem/progenitor cells and the expression of stem cell markers. These findings suggest that chronic inflammation may alter the direction of differentiation toward undifferentiated state and that drawbacks may enable cells to redifferentiate to intestinal metaplasia or neoplasia.

In this study, we deal with a dual active bridge (DAB) converter-based battery charger in a standalone wind power generation system (WPGS) with a small-scale wind turbine. However, the power conversion efficiency under the low power output in the discharging mode is low. In this paper, we propose variable DC-link voltage control in a standalone WPGS with a DAB converter under a light load. The proposed control can compensate for the shortage of generated power and suppress the peak value of the transformer current. Simulation results demonstrate that the proposed control can decrease the peak value of the transformer current and improve the power conversion efficiency of the DAB converter. An experimental setup was constructed to confirm the basic operation of the variable DC-link voltage control. In addition, a reference DC-link voltage switchover control is proposed to enable a high-efficiency drive under all load ranges. From simulation results, the power loss can be reduced by the switchover control of the reference DC-link voltage.

This paper deals with power quality compensation in single-phase three-wire distribution feeders using a constant DC-capacitor voltage-control (CDCVC)-based strategy of the previously proposed bidirectional battery charger (BBC) for electric vehicles under the distorted source-voltage and load-current conditions. Instantaneous active power flowing into the three-leg pulse-width-modulated (PWM) rectifier in the BBC is discussed. The instantaneous power flowing into the three-leg PWM rectifier demonstrates that the CDCVC-based strategy obtains balanced and sinusoidal source currents at a unity power factor, where the source-side active power is balanced with the load-side active power. Simulation and experimental results demonstrate that balanced and sinusoidal source currents at a unity power factor are attained in single-phase three-wire distribution feeders with both battery-charging and -discharging operations for electric vehicles even though both source voltage and load currents are distorted.

Background. Vonoprazan affords more clinical benefits than proton pump inhibitors (PPIs) during the healing of gastroduodenal ulcers. However, it remains controversial whether vonoprazan is more effective than PPIs when used to heal artificial ulcers arising after endoscopic submucosal dissection (ESD). Aim. This study investigated the effects of vonoprazan compared with esomeprazole on the healing of post-ESD artificial ulcers. Methods. Sixty patients who underwent gastric ESD between May 2015 and May 2017 were randomized to treatment with vonoprazan (V group) or esomeprazole (E group) for 8 weeks. Upper endoscopy was performed at 4 and 8 weeks after ESD, and drug effects were estimated based on the ulcer healing rates and shrinkage rates. Results. Fifty-three patients were analyzed. The respective 4- and 8-week ulcer healing rates did not differ significantly between V and E groups (8.0 versus 11.5%, P=0.669; 88.9 versus 84.6%, P=0.420). Similarly, the respective 4- and 8-week ulcer shrinkage rates did not differ significantly between V and E groups (96.8 versus 97.5%, P=0.656; 100 versus 100%, P=0.257). Conclusion. The healing of artificial ulcers after ESD did not differ using vonoprazan or esomeprazole. Both vonoprazan and esomeprazole were effective when used to promote artificial ulcer healing after ESD.

Aim. To assess the efficacy of 7-day first-line Helicobacter pylori eradication with vonoprazan (VPZ), clarithromycin (CAM), and metronidazole (MNZ) in patients with penicillin allergy. Methods. Patients with penicillin allergy, diagnosed with Helicobacter pylori infection and did not have history of Helicobacter pylori eradication, were eligible for the study. Twenty patients were prospectively treated with 20 mg VPZ twice daily, 200 or 400 mg CAM twice daily, and 250 mg MNZ twice daily for 7 days. We also collected the data from 30 patients retrospectively treated with proton pump inhibitor (PPI), CAM, and MNZ. Safety was evaluated in patients completing an adverse effect questionnaire. Results. Both the intention-to-treat and per-protocol effectiveness of VPZ-based eradication were 100% (95% CI: 86.1–100%; n=20). The eradication rates of PPI-based regimen were 83.3% (95% CI: 65.3–94.4%) in the ITT and 82.7% (95% CI: 64.2–94.2%) in the PP analyses. Abdominal fullness was more frequent in VCM compared to PCM. However, all patients with VCM regimen had taken 100% of their course of medication. Conclusion. Triple therapy with VPZ, CAM, and MNZ is well tolerated and effective for eradicating Helicobacter pylori in patients allergic to penicillin. This study was registered in the UMIN Clinical Trials Registry as UMIN000016335.

This paper proposes a novel Maximum Power Point Tracking (MPPT) control method of thermoelectric power generation for the constant load. This paper reveals the characteristics and the internal resistance of thermoelectric power module (TM). Analyzing the thermoelectric power generation system with boost chopper by state space averaging method, the output voltage and current of TM are estimated by with only single current sensor. The proposed method can seek without calculating the output power of TM in this proposed method. The basic principle of the proposed MPPT control method is discussed, and then confirmed by digital computer simulation using PSIM. Simulation results demonstrate that the output voltage can track the maximum power point voltage by the proposed MPPT control method. The generated power of the TM is 0.36 W when the temperature difference is 35 °C. This is well accorded with the V-P characteristics.

This paper deals with a design and experimental verification of 400-W class light-emitting diode (LED) driver with cooperative control method for two-parallel connected DC/DC converters. In the cooperative control method, one DC/DC converter is selected to supply the output current for the LED, based on the reference value of the LED current. Thus, the proposed cooperative-control strategy achieves wide dimming range operation. The discontinuous current conduction mode (DCM) operation improves the total harmonic distortion (THD) value on the AC side of the LED driver. The standard of Electrical Applications and Materials Safety Act in Japan has defined the flicker frequency and minimum optical output. The smoothing capacitors are designed by considering the power flow and LED current ripple for satisfying the standard. A prototype LED driver is constructed and tested. Experimental results demonstrate that a wide dimming operation range from 1 to 100% is achieved with a THD value less than 10% on the AC side, by the proposed control strategy. The authors compare the power conversion efficiency between Si- and SiC-metal-oxide-semiconductor field-effect transistors (MOSFETs) based LED driver. The maximum power conversion efficiency by using SiC-MOSFETs based LED driver is 91.4%. Finally, the variable switching frequency method is proposed for improving the power conversion efficiency for a low LED current region.

This paper presents an improvement in harmonic compensation performance of a previously proposed smart charger (SC) with a constant dc-capacitor voltage-control (CDCVC) strategy for electric vehicles (EVs) in single-phase three-wire distribution feeders (SPTWDFs). A controller for 3rd harmonic currents in d-q coordinates is added to the previously proposed SC. This addition improves harmonic compensation performance of the source currents. We briefly introduce harmonic current compensation using the previously proposed CDCVC-based algorithm for the SC. Then, the basic principles of the proposed controller for the 3rd harmonic currents in d-q coordinates are discussed in detail. It is shown that synchronization of the current controllers for both the fundamental and 3rd harmonic components is required. The switching frequency of a three-leg pulse-width modulated rectifier with a bidirectional dc–dc converter, which performs the SC, is determined considering the synchronization of the current controllers. Simulation and experimental results demonstrate that balanced and sinusoidal source currents with a unity power factor are achieved during both battery charging and discharging operations in EVs, improving the harmonic compensation performance of the previously proposed SC. Experimental results also demonstrate that the total harmonic distortion values of source currents are improved by 8.4% and 3.6% with the proposed controller for 3rd harmonic currents, when the SC is discharging, for example.

This paper proposes the inrush current suppressor using an AC chopper in a large-capacity wind power generation system (WPGS) with two squirrel-cage induction machines (SCIMs), which are switched over depending on the wind speed. The input side of the AC chopper is connected to the source in parallel. The output side of the AC chopper is connected in series with the SCIM through matching transformers. In the proposed inrush current suppressor, the output voltage of the AC chopper is the same as the receiving-end voltage before connecting the SCIM. By gradually decreasing the output voltage of the AC chopper, the applied voltage of the SCIM is gradually increased without the inrush current. The basic principle of the proposed inrush current suppressor is discussed in detail. A computer simulation is implemented to confirm the validity and practicability of the proposed inrush current suppressor using a power system computer-aided design/electromagnetic transients including DC (PSCAD/EMTDC). Simulation results demonstrate that the proposed inrush current suppressor can suppress the inrush current.

Correction Unfortunately, the original article [1] contained an error incorporated during production. A duplicated version of Table 1 was published in place of Table 2. Table 2 has been corrected in the original article and is also included correctly below.

Objectives: Since the development of techniques for endoscopic submucosal dissection (ESD), the indication range of endoscopic resection (ER) has been extended in early gastric cancer (EGC) treatment. For undifferentiated-type EGC, tumors with an intramucosal depth of invasion, no ulceration and a diameter of 20 mm or less were included in the expanded indications for ER in the Japanese Gastric Cancer Treatment Guidelines 2010. Nonetheless, because of difficulty in detecting lesions that meet the criteria for ER, the number of endoscopically resected cases of undifferentiated-type EGC is less than that of differentiated-type EGC. Methods: We retrospectively investigated the outcomes of ESD in 38 patients with 40 lesions of EGC in which the dominant pathological type was confirmed to be undifferentiated (signet ring cell carcinoma, poorly differentiated adenocarcinoma, mucinous adenocarcinoma) on histological examination of resected specimens. Results: Margin involvement and submucosal infiltration were common noncurative factors. Precise evaluation of the area and depth of lesions is a problem to be solved. Among a total of five patients with involved or uncertain horizontal margins, one of two patients who underwent additional surgery had residual cancer, and one of three patients who were observed had recurrence. Conclusions: Undifferentiated-type EGC with a positive horizontal margin may relapse after ESD. It is therefore essential to precisely evaluate the area of the lesion and to perform resection with an adequate safety margin to decrease the risk of recurrence.

Abstract: We consider quantum diffusion of the initially localized wavepacket in one-dimensional kicked disordered system with classical coherent perturbation. The wavepacket localizes in the unperturbed kicked Anderson model. However, the wavepacket get delocalized even by coupling with monochromatic perturbation. We call the state "dynamically delocalized state". It is numerically shown that the delocalized wavepacket spread obeying diffusion law, and the perturbation strength dependence of the diffusion rate is given. The sensitivity of the delocalized state is also shown by the time-reversal experiment after random change in phase of the wavepacket. Moreover, it is found that the diffusion strongly depend on the initial phase of the perturbation. We discuss a relation between the "classicalization" of the quantum wave packet and the time-dependence of the initial phase dependence. The complex structure of the initial phase dependence is related to the entropy production in the quantum system.

This paper proposes a new hybrid static VAR compensator (SVC) with a series active filter (AF). The proposed hybrid SVC consists of a series AF and SVC. The series AF, which is connected in series to phase-leading capacitors in the SVC, performs for a resistor for source-side harmonic currents. A sinusoidal source current with a unity power factor is obtained with the series AF, although the thyristor-controlled reactor generates harmonic currents. A digital computer simulation was implemented to confirm the validity and high practicability of the proposed hybrid SVC using PSIM software. The simulation results demonstrate that sinusoidal source currents with a unity power factor are achieved with the proposed hybrid SVC.

This paper discusses harmonic current compensation of the constant DC-capacitor voltage-control (CDCVC)-based strategy of smart chargers for electric vehicles (EVs) in single-phase three-wire distribution feeders (SPTWDFs) under nonlinear load conditions. The basic principle of the CDCVC-based harmonics compensation strategy under nonlinear load conditions is discussed in detail. The instantaneous power flowing into the three-leg pulse-width modulated (PWM) rectifier, which performs as a smart charger, shows that the CDCVC-based strategy achieves balanced and sinusoidal source currents with a unity power factor. The CDCVC-based harmonics compensation strategy does not require any calculation blocks of fundamental reactive, unbalanced active, and harmonic currents. Thus, the authors propose a simplified algorithm to compensate for reactive, unbalanced active, and harmonic currents. A digital computer simulation is implemented to confirm the validity and high practicability of the CDCVC-based harmonics compensation strategy using PSIM software. Simulation results demonstrate that balanced and sinusoidal source currents with a unity power factor in SPTWDFs are obtained on the secondary side of the pole-mounted distribution transformer (PMDT) during both the battery-charging and discharging operations in EVs, compensating for the reactive, unbalanced active, and harmonic currents.

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This study presents a new modulation method for multidirectional matrix converter (MDMC), based on the direct duty ratio pulse width modulation (DDPWM). In this study, a new structure of MDMC has been proposed to control the power flow direction through the stand-alone battery based system and hybrid vehicle. The modulation method acts based on the average voltage over one switching period concept. Therefore, in order to determine the duty ratio for each switch, the instantaneous input voltages are captured and compared with triangular waveform continuously. By selecting the proper switching pattern and changing the slope of the carriers, the sinusoidal input current can be synthesized with high power factor and desired output voltage. The proposed system increases the discharging time of the battery by injecting the power to the system from the generator and battery at the same time. Thus, it makes the battery life longer and saves more energy. This paper also derived necessary equation for proposed modulation method as well as detail of analysis and modulation algorithm. The theoretical and modulation concepts presented have been verified in MATLAB simulation.

This paper describes the reduced capacity of the inrush current suppressor using a matrix converter (MC) in a large-capacity wind power generation system (WPGS) with two squirrel-cage induction machines (SCIMs). These SCIMs are switched over depending on the wind speed. The input side of the MC is connected to the source in parallel. The output side of the MC is connected in series with the SCIM through matching transformers. The modulation method of the MC used is direct duty ratio pulse width modulation. The reference output voltage of the MC is decided by multiplying the SCIM current with the variable control gain. Therefore, the MC performs as resistors for the inrush current. Digital computer simulation is implemented to confirm the validity and practicability of the proposed inrush current suppressor using PSCAD/EMTDC (power system computer-aided design/electromagnetic transients including DC). Furthermore, the equivalent resistance of the MC is decided by the relationship between the equivalent resistance and the capacity of the MC. Simulation results demonstrate that the proposed inrush current suppressor can suppress the inrush current perfectly.

Quantum transport for DNA conduction has been widely studied with interest in application as a candidate in making nanowires as well as interest in the scientific mechanism. In this paper, we review recent works concerning the electronic states and the conduction/transfer in DNA polymers. We have mainly investigated the energy-band structure and the correlation effects of localization property in the two- and three-chain systems (ladder model) with long-range correlation as a simple model for electronic property in a double strand of DNA by using the tight-bindingmodel. In addition, we investigated the localization properties of electronic states in several actual DNA sequences such as bacteriophages of Escherichia coli, human-chromosome 22, compared with those of the artificial disordered sequences with correlation. The charge-transfer properties for poly(dA)-poly(dT) and poly(dG)-poly(dC) DNA polymers are also presented in terms of localization lengths within the frameworks of the polaron models due to the coupling between the charge carriers and the lattice vibrations of the double strand of DNA.

Background: Our search for plant-derived ceramides from sustainable sources led to the discovery of ceramides and glucosylceramides in wine lees. Objective: This study evaluated the efficacy and safety of wine lees extract (WLE)-derived ceramides and glucosylceramides in enhancing skin barrier function. Methods: A randomized, double-blind, placebo-controlled study was conducted with 30 healthy Japanese subjects aged 20–64. Subjects were allocated to receive either the WLE-derived ceramides and glucosylceramides (test group) or placebo for 12 weeks. The primary outcome was transepidermal water loss (TEWL), and secondary outcomes included skin hydration, visual analog scale (VAS) of itching sensation, and the Japanese Skindex-29. Results: One participant withdrew for personal reasons, resulting in 29 subjects for data analysis (placebo n = 15; test n = 14). The test group showed a tendency of lower TEWL compared to the placebo after 8 weeks (p = 0.07). Furthermore, after 12 weeks of administration, the test group had significantly lower TEWL than the placebo (p = 0.04). On the other hand, no significant differences were observed in the secondary outcome parameters. No adverse events related to the supplements were reported. Conclusions: Oral supplementation of WLE-derived ceramides and glucosylceramides is a prominent and safe approach to enhancing skin barrier function and health. Trial registration: (UMIN000050422). [ABSTRACT FROM AUTHOR]