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Aim The clinical impact of abdominal aortic calcification (AAC) in patients who undergo hepatectomy for hepatocellular carcinoma (HCC) is unknown. Methods To evaluate the impact of AAC on clinical outcomes, we analyzed 203 patients who underwent hepatectomy for HCC between 2010 and 2013. Results Kaplan–Meier survival curve analysis showed significantly worse overall survival (OS) in the high AAC group than in the low AAC group. The recurrence‐free survival (RFS) was also significantly worse in the high AAC group. In the multivariate analysis, high AAC (hazard ratio [HR], 2.51; 95% confidence interval [CI], 1.24–5.09; P = .01) was an independent risk factor for poor OS after hepatectomy for HCC. High AAC was also an independent risk factor for poor RFS (HR, 1.69; 95% CI, 1.04–2.76; P = .04). Conclusions Abdominal aortic calcification had a strong relationship with poor OS and RFS after hepatectomy for HCC. We suggest that AAC had a relationship with smoking and diabetes; therefore, AAC could reflect a surrogate for older age, worse health status, and inflammatory score., Kaplan–Meier survival curve analysis showed significantly worse overall survival in the high abdominal aortic calcification (AAC) group than in the low AAC group.

INTRODUCTION Despite the popularity of laparoscopic surgery, it remains unclear whether residual pneumoperitoneum influences the patient's postoperative course. This study aimed to evaluate the characteristics of residual pneumoperitoneum. METHODS This retrospective study included 201 Japanese patients who had undergone elective laparoscopic colorectal surgery. The patients were divided into groups, with and without anastomotic failure; the non-anastomotic failure group was further divided into subgroups, with and without residual pneumoperitoneum. Patient characteristics were compared between the various groups. RESULTS The group with residual pneumoperitoneum included 57 patients (30.3%). Percutaneous drainage was required for one patient with residual pneumoperitoneum. Univariate analyses revealed that residual pneumoperitoneum was associated with low values for body mass index (BMI) and subcutaneous fat area (SFA). Furthermore, relative to the group with anastomotic failure, the group without anastomotic failure but with residual pneumoperitoneum had lower values for inflammatory markers. CONCLUSION Low BMI and SFA values were identified as risk factors for residual pneumoperitoneum. Inflammatory markers may be useful as indicators for avoiding emergent surgery when it is difficult to differentiate between asymptomatic residual pneumoperitoneum and free air related to anastomotic failure.

Tumor budding (TB) has been described as an adverse prognostic marker for operable colorectal cancer (CRC); however, a limited number of studies have demonstrated the prognostic significance of TB in patients with drug therapy. This study was conducted to determine the predictive power of TB in stage III CRC patients who received adjuvant chemotherapy. We retrospectively collected clinicopathological data including TB of 237 stage III colorectal cancer patients at Hiroshima University Hospital between July 1, 2006 and June 31, 2019. Differential disease-free survival (DFS) was investigated according to TB status. This study included 237 patients with a median age of 67 years, comprising patients who underwent surgery alone (n = 65), 5-fluorouracil (5-FU) monotherapy (n = 129), and oxaliplatin-based chemotherapy (n = 43). Overall, 81 patients developed disease recurrence, and 33 patients died of cancer-related causes. The TB status was categorized into two groups: 99 with low budding (

Background and aims: Lenvatinib (LEN) is a newly developed tyrosine kinase inhibitor, and is approved as a first-line treatment for advanced hepatocellular carcinoma (HCC) in Japan. This retrospective multi-center study investigated the effect of the relative dose intensity (RDI) of LEN on response rate, progression-free survival (PFS), and overall survival (OS). Methods: This retrospective study enrolled 123 patients with advanced HCC who were treated with LEN at six hospitals in Japan between March 2018 and December 2019. These patients were divided into two groups: RDI ≥70% (RDI 70 group, N = 70) or RDI

Background: Although radiofrequency ablation (RFA) is a minimally invasive treatment for early-stage hepatocellular carcinoma (HCC), it remains unclear whether RFA achieves favorable outcomes in patients aged ≥80 years. This study aimed to determine the efficacy and safety of RFA for HCC in patients aged ≥80 years. Methods: A total of 512 naïve patients with HCC who had undergone RFA from January 2001 to December 2016 were enrolled. They were categorized into the ≥80-year-old group and the control group (aged

Background and aims Abdominal aortic calcification (AAC) was reported as a poor prognostic factor among liver transplantation. However, donor AAC is not enough discussed. We analyzed the impact of the donor AAC level on graft function on outcomes following living donor liver transplantation (LDLT). A total of 133 consecutive patients who had undergone LDLT were divided into two groups (non-AAC group and AAC group) according to their donor AAC level by plain computed tomography. Results The rate of postoperative biliary complications (BC) was significantly higher in AAC group (N=17) than in non-AAC group (N=116) (HR, 2.77; 95% CI, 1.32-5.83; p=.0008). The Cox proportional-hazards regression model revealed that donor AAC (HR, 4.15; 95% CI, 1.93-8.97; p = .0003) and right lobe graft (HR, 2.81; 95% CI, 1.41-5.61; p=.003) increased the risk of BC. Conversely, splenectomy (HR, 0.39; 95% CI, 0.16-0.92; p=.03) decreased the risk of BC after LDLT independently. The long-term survival was also significantly worse in AAC group than in non-AAC group. (HR, 2.25; 95% CI, 1.04-4.89; p=.04) CONCLUSION: Donor AAC was an independent prognostic factor for BC among patients undergoing LDLT. Although further investigations are needed to verify our results, the levels of donor AAC could be a useful tool to identify the risks of BC, and predict better outcomes following LDLT.

Background and Objective Experience of the use of lenvatinib (LEN) in the clinical setting remains limited. We conducted this study to elucidate the factors associated with progression-free survival (PFS) in patients with advanced HCC treated with LEN. Methods In this multicenter retrospective study, we analyzed data on patient characteristics, treatment outcomes, and adverse events (AEs) for 77 patients with advanced hepatocellular carcinoma (HCC). We also analyzed PFS and factors that influence PFS. Results The response rate to LEN was 29.9% and the disease control rate was 77.9%. Patients who achieved relative dose intensities of more than 70% had better outcomes (response rate 45.2% vs. 11.4%, P

Eradication of hepatitis C virus (HCV) using direct acting antiviral agents (DAAs) has been reported to alter liver function and reduce the recurrence rate after curative treatment in naïve hepatocellular carcinoma (HCC) patients. However, it is not well known whether administration of DAAs had favourable effect on HCC patients with multiple courses of recurrence. We retrospectively extracted 146 HCV-related HCC (C-HCC) patients who received curative treatment using radiofrequency ablation (RFA) followed by eradication treatment with DAA between 1 January 2015 and 31 December 2017. We also extracted 184 C-HCC patients who were curatively treated using RFA without HCV eradication treatment between 1 January 2009 and 31 July 2014 as controls. We used propensity score matching method and adjusted following factors between the 2 groups: age, sex, liver function, number of recurrence times, tumour diameter and tumour numbers. We finally enrolled 47 C-HCC patients with eradication of HCV, and 47 C-HCC patients without HCV eradication as controls. Primary end point was time to curative treatment failure. We defined time to curative treatment failure as the interval from curative treatment initiation to premature discontinuation of this type of therapy. Their clinical data, time to curative treatment failure and overall survival were compared. We also assessed the prognostic values of time to curative treatment failure and overall survival using multivariate Cox proportional hazard models. The median age was 74.8 years, 60 patients (63.8%) were male, and 81 patients (86.2%) were Child-Pugh class A. The median tumour number was 1, tumour diameter was 20 mm, and frequency of recurrence was 3 times. There were no significant differences about patients' backgrounds between the 2 groups. The cumulative time to curative treatment failure rates of patients who received DAA were 93.6% and 73.2% at 1 and 3 years, respectively; those of controls were 72.5%, and 37.1% (p .01). Multivariate analysis indicated that eradication with DAAs (HR 0.23, 95% CI; 0.12-0.43, p .01) and DCP 50 mAU/ml (HR 2.62, 95% CI; 1.45-4.74, p .01) as independent factors contributed to time to curative treatment failure. The cumulative overall survival rates of patients who received DAAs were 93.6% and 72.6% at 1 and 3 years, respectively; those of controls were 72.8% and 37.4% (p .01). Multivariate analysis indicated that eradication with DAAs (HR 0.32, 95% CI; 0.17-0.60, p .01) and frequency of recurrence times (HR 1.20 per 1 time, 95% CI; 1.01-1.42, p = .038) as independent factors related to overall survival. Eradication of HCV using DAAs prolonged not only time to curative treatment failure but also overall survival even in C-HCC patients with multiple courses of recurrence.

Solid oxide fuel cells (SOFCs) with proton-conducting solid electrolyte, instead of the oxide-ion conducting solid electrolyte have attracted attentions because of their high potential to reduce operating temperatures and to enhance the electrical efficiencies of SOFCs. In addition, the proton-conducting SOFCs with multistage electrochemical oxidation configuration will be promising technology for critically-high electric efficiencies. However, it is known that there are non-negligible charge -carriers other than protons in typical proton-conducting solid oxide electrolytes at relatively high temperatures. The existence of the partial conductivities of holes and/or electrons will cause the internal leakage current that consumes fuel but never generates any electrical power output. The higher ratio of the leakage current to external current will more deteriorate the electrical efficiency. In this study, the effects of blocking -layers formed on the air side surface of base electrolyte layer consisting of BaZr0.8Y0.2O3-δ (BZY82) for suppressing the leakage current have been investigated by using electrochemical parameters of the partial conduction of the materials. The chemical potential profile and leakage current showed large dependence on the material of the blocking -layer. Lanthanum tungstate was found to play a role as unique and strong blocking -layer against the leakage current.

Purpose The number of patients on antiplatelet therapy (APT) who need surgery is increasing; however, it is unclear whether APT should be continued for abdominal surgery, particularly laparoscopic colorectal surgery. We investigated the safety of continuing APT for patients undergoing laparoscopic colorectal surgery. Methods We collected retrospective data from 529 patients who underwent laparoscopic colorectal surgery at Hiroshima University between January, 2013 and December, 2018. We analyzed information related to APT. Thirty-six pairs were matched by the propensity score method between patients on APT (APT+) and those not on APT (APT−). We compared the surgical outcomes of both groups. Results Among 463 patients eligible for the study, 48 were on APT for cerebrovascular or cardiovascular disease, and 36 continued to take aspirin. In the case-matched comparison, the amount of intraoperative blood loss in the APT+ group was not significantly higher than that in the APT− group, and the incidences of bleeding complications, thromboembolic complications, and other complications were not significantly different between the groups. Conclusion In a case-matched comparison, continuation of aspirin during laparoscopic colorectal surgery did not increase perioperative complications. In laparoscopic colorectal surgery, continuation of aspirin is an acceptable strategy for patients with thromboembolic risk caused by interruption of APT.

Refractory ascites after liver transplant commonly occurs in living donor liver transplant (LDLT). Refractory ascites is associated with postoperative complications and poor prognosis. This study sought to determine the risk factors of refractory ascites and discuss their perioperative management.A retrospective study of 122 living donor liver transplant recipients between 2008 and 2017 was performed to analyze the risk factors, incidence, and characteristics of refractory ascites. Refractory ascites post LDLT was defined as the production of ascites fluid1000 mL/d on postoperative day 14 or required repeated drainage.A total of 24 patients (19.6%) developed refractory ascites. The 1-year survival rate was significantly worse in the refractory ascites group compared with the nonrefractory ascites group (P .001). In a univariate analysis, patients with refractory ascites had a higher Model for End-Stage Liver Disease (MELD) score, donor age, presence of left lobe graft, ascites at laparotomy, portal venous pressure just after surgery, cold ischemia time, and absence of hepatocellular carcinoma compared with patients without refractory ascites. Multivariate proportional regression analyses revealed that MELD score ≥20, left lobe graft, donor age 50 years or older, and ascites at laparotomy ≥350 mL were independently associated with refractory ascites. Postoperative complications, such as bleeding (P .001), sepsis (P .001), and bloodstream infection within 30 days after LDLT (P .00), were significantly higher in the refractory ascites group.Refractory ascites is associated with reduced 1-year survival and increased postoperative complications. Four factors including MELD score ≥20, donor age 50 years or older, presence of left graft, and ascites at laparotomy ≥350 mL were independent predictors for refractory ascites.

In order to develop a technical process to display holographic reconstructed images in colors, it seems to be very important to extend the holographic displayable region of colors, and so the study of displaying process of the reconstructed images in colors with the use of blue-violet laser light (wavelength: 405 nm)seems to be crucial. We have studied how to improve the characteristics of the displayable region of the reconstructed images using blue-violet laser light when time-sharing multiplex reconstructing technique is employed. In this report, we are going to show some improved displaying characteristics of the object with the curved shape, and to propose some useful basic suggestions for a colorful display of reconstructed holographic images when blue-violet laser light is applied.

Evidence on risk factors for postoperative recurrence in patients with colorectal cancer (CRC) confined to pathological stage I is limited. Therefore, this study aimed to identify the risk factors for recurrence in patients with stage I CRC. Data on clinicopathological factors and blood tests of patients diagnosed with pathological stage I CRC at Hiroshima University Hospital between April 1, 2010, and December 31, 2018, were retrospectively obtained. The statistical significance between the clinical factors and postoperative recurrence was also investigated. A total of 244 patients were included. The median observation period was 45 months. There were 17 patients (6.6%) with a postoperative recurrence (8 local and 9 distant recurrences). In the log-lank test, rectal cancer (p = 0.004), pT2 (p = 0.020) and organ/space surgical site infection (SSI) (p = 0.008) were significantly associated with postoperative recurrence. In a multivariate analysis, rectal cancer (hazard ratio [HR] 3.678, 95% confidence interval [CI] 1.184–11.425, p = 0.024) and organ/space SSI (HR 3.137, 95% CI 1.013–9.713, p = 0.047) were independently associated with a higher recurrence rate. Among 18 patients with organ/space SSI, 4 recurrences occurred, all of which were distant metastases. Organ/space SSI significantly affects the postoperative recurrence in patients with stage I CRC.

Highlights • Although von Willebrand disease (VWD) is a common inherited bleeding disease, only 1 case of hepatectomy in a patient with VWD has been described. • Perioperative hemostatic management is important especially in patients with VWD undergoing surgery because of the dysfunction of the platelet and destabilization of the blood clotting factor VIII. • The patient was successfully treated by administering factor VIII/von Willebrand factor concentrate and by measuring activated partial thromboplastin time as an index for perioperative hemostatic management., Introduction Although von Willebrand disease (VWD) is a common inherited bleeding disorder, very few cases of surgery in patients with VWD have been reported. Presentation of case A 77-year-old man was referred to our hospital for treatment of hepatocellular carcinoma (HCC) based on type C chronic hepatitis. He had also been treated for VWD in the hematology department of another hospital. Partial hepatectomy was performed with the administration of factor VIII/von Willebrand factor concentrate just before and after the operation. The perioperative course was uneventful, and the patient was discharged 12 days after surgery. Discussion VWD causes dysfunction of the platelet and destabilization of the blood clotting factor VIII. The patient was successfully treated with measurement of activated partial thromboplastin time (APTT) as an index for the management of hemostasis. Conclusion This report describes a rare case of a successful perioperative management of hepatectomy in a patient with VWD.

Highlights • An enterolith occurring in the duodenal afferent loop after distal gastrectomy, leading to obstructive jaundice and ileus is rare. • Although afferent loop enterolith formation is uncommon, it should be considered when a patient with a history of B-II gastrectomy or Roux-en-Y reconstruction presents with fever, abdominal pain, or other symptoms suggesting acute cholangitis. • Surgical treatment should be considered for afferent loop obstruction or intestinal obstruction that is refractory to conservative treatment., Introduction Afferent loop obstruction is an uncommon complication associated with Billroth II reconstruction or Roux-en-Y reconstruction after gastrectomy. Moreover, cases where the obstruction is caused by enterolith are rare. Here, we report a rare case of afferent loop obstruction caused by an enterolith after Roux-en-Y reconstruction of gastrectomy; subsequently, leading to ileus in the ileum. Presentation of case An 84-year-old man who received a Roux-en-Y distal gastrectomy for gastric cancer presented with symptoms of fever and jaundice 14 months later. Computed tomography (CT) scan revealed an enterolith in the duodenal afferent loop and a dilated intrahepatic bile duct. Although the obstructive jaundice and fever disappeared with conservative therapy, ileus occurred due to the movement of the enterolith into the ileum, which was refractory to conservative therapy. Therefore, enterotomy was performed to remove the enterolith, and the patient had an uneventful recovery. Histologically, the enterolith derived from food residue. No postsurgical sign of recurrence has been noted for 6 months. Conclusion We report a rare case where an enterolith in a duodenal afferent loop after distal gastrectomy led to obstructive jaundice, and subsequently, caused ileus by its movement into the ileum.

Highlights • Appendicitis with liver abscess and sessile serrated adenoma/polyp is rare. • Ileocecal resection was performed for an inflammatory mass in the ileocecum. • The patient was successfully treated with a combination of surgery and antibiotics., Introduction Although appendicitis is a common disease, appendicitis concurrent with liver abscesses and sessile serrated adenoma/polyp (SSA/P) is rare. Presentation of case A 69-year-old man presented with symptoms of abdominal pain and fever. Computed tomography (CT) revealed multiple liver abscesses and an enlarged appendix with a pseudotumoral appearance, which suggested acute appendicitis. In the emergency operation, ileocecal resection was performed for the perforated appendicitis with an inflammatory mass in the ileocecum. On macroscopic examination, the torose lesion was localized at next to the appendiceal orifice. The tumor was diagnosed as SSA/P based on the microscopic finding. The postoperative course was uneventful, and the liver abscesses were cured by antibiotic therapy. The patient was discharged 17 days after the surgery. Discussion In this case, SSA/P localization at next to the appendiceal orifice was suggested as the cause of the perforated appendicitis with multiple liver abscesses. The patient was successfully treated with a combination of surgery and antibiotic therapy. Conclusion This is the first reported case of a patient with SSA/P that led to acute appendicitis with multiple pyogenic liver abscesses.

Objectives The aim of this study was to investigate whether MUC1 expression is associated with progression of intraductal papillary mucinous neoplasms with worrisome features during follow-up. Methods Fifteen patients positive for MUC1 and negative for MUC2 (MUC1 group) and 16 patients negative for MUC1 and MUC2 (control group) were followed up and examined for changes in diameters of the main and ectatic branches of pancreatic ducts, enlargement of mural nodules, and appearance of a solid mass, by imaging studies. All of them presented worrisome features, and none had "high-risk stigmata." Results The sizes of the main and ectatic branches of pancreatic ducts increased in 8 (53.3%) and 8 (53.3%) patients, respectively, of the MUC1 group and in 1 (6.3%) and 1 (6.3%) patients, respectively, of the control group (P = 0.0059 and 0.0059, respectively). A solid mass developed in 6 patients (33.3%) of the MUC1 group but in none of the control group patients (P = 0.0373). Conclusions Positive MUC1 expression in cell block cytology specimens may be associated with progressive dilation of the main and ectatic branches of pancreatic ducts and appearance of a solid mass in patients with intraductal papillary mucinous neoplasm with worrisome features during follow-up.

Highlights • Completely different types of GIST rupture have been reported as same perforation type. • We classified retrieved cases of GIST rupture to three types: abscess type, hemoperitoneum type, bowel perforation type. • Each type demonstrates a specific mechanism of perforation causing characteristic complaints., Introduction Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract. Overt peritonitis caused by GIST rupture is very uncommon. Three types of GIST rupture have been described: closed perforation due to abscess (abscess type), hemoperitoneum leading to rupture of the hematoma capsule in the tumor (hemoperitoneum type), and perforation of the digestive tract via a fistula leading to central necrosis of the tumor (bowel perforation type). This report describes a patient with spontaneous tumor rupture and diffuse peritonitis, a variant of the bowel perforation type of GIST rupture. Presentation of case A 74-year-old man presented with symptoms of vomiting and abdominal pain. Computed tomography (CT) scan revealed an approximately 10 × 7-cm mass in the pelvis with free air and fluid collection. Emergency laparotomy revealed a tumor in the jejunum, which was ruptured with a hole measuring 5 mm in diameter. The tumor and part of the jejunum were resected. Immunohistochemically, the mass was diagnosed as a GIST originating from the gastrointestinal tract. Despite chemotherapy with imatinib mesylate, the patient died 22 months after surgery. Conclusions This report describes a patient with acute diffuse peritonitis due to spontaneous rupture of a primary GIST of the jejunum.

The purpose of this study is to operate various computers around us using our own smartphones. Methods for operating computers around the home by voice, such as the Internet of Things (IoT) appliances, are now widespread. However, there are problems with operation by voice; it is limited in terms of instruction patterns that can be expressed, and it cannot be used simultaneously by many users. To solve the problem, we propose a method to determine the location pointed to by a user with a smartphone gyro sensor. This method achieves controller integration, multiple functions, and simultaneous use by multiple people.

Very low anterior resection (VLAR) is performed widely, but some patients are left with fecal incontinence (FI), which compromises their quality of life (QOL) severely. This study sought to identify the predictive factors of postoperative FI after VLAR, which remain unclear. We evaluated the anorectal manometry data of patients who underwent VLAR to identify the risk factors for postoperative FI among the various clinicopathological factors and manometric characteristics. FI and QOL were analyzed using the Wexner score and EORTC QLQ-C30, respectively. The subjects of this study were 40 patients who underwent VLAR for low rectal cancer between April, 2015 and May, 2018. There were 11 (27%) patients in the major-FI group and 29 (73%) in the minor-FI group. Multivariate analysis revealed that low preoperative incremental maximum squeeze pressure (iMSP) was an independent risk factor for postoperative major-FI. Postoperative QOL tended to be worse in the major-FI group. Preoperative low iMSP increases the risk of major-FI and impaired QOL after VLAR. This highlights the importance of performing preoperative anorectal manometry to evaluate the patient’s anal function as well as to select the most appropriate operative procedure and early multifaceted treatment such as medication, rehabilitation, and biofeedback for postoperative FI.

Background Refractory ascites is one of the major complications of liver transplant (LT) and is associated with increased morbidity and mortality. The aim of this study was to analyze the efficacy and safety of novel cell-free and concentrated ascites reinfusion therapy (KM-CART) for the treatment of refractory ascites during preoperative living donor liver transplant. Methods Forty KM-CART procedures were performed on 8 liver transplant candidates. We investigated the safety and efficacy of KM-CART in terms of the processed ascites, adverse events, laboratory data, and patient condition. Results By using KM-CART, an average of 12.5 L (range, 2.6–26.1 L) of ascites was filtered and concentrated to 0.5 L (range, 0.1–1.6 L) in 62 minutes (range, 8-187 minutes). Final products contained 21.5 g (range, 2.5–65.6 g) of albumin and 13.5 g (range, 1.5–61.8 g) of globulin. No endotoxin contamination was detected in the ascites. Although the incidence of adverse events was 35.0% (including fever, hypotension, bleeding, leg cramps, and nausea), all of these could be treated conservatively. Body weight and oral intake were significantly improved after KM-CART. Furthermore, the use of fresh frozen plasma for the LT recipients with KM-CART was significantly lower than that for patients without KM-CART. In addition, no patients lost their opportunity for LT because of adverse events due to KM-CART. Conclusions Our findings show that KM-CART could be a promising option for the treatment of refractory ascites during the preoperative period of LT. This study provides the foundation for further large-scale prospective studies.

The role of telecom carrier networks has shifted from the provision of telephone services to that of Internet infrastructures, making it inevitable to invest in equipment capable of handling the rapidly increasing traffic due to the distribution of video and other bandwidth-heavy contents. This has given rise to management needs for reducing the cost of communication systems as a whole. Likewise, software used in communication systems is increasingly becoming more complex and larger in scale to accommodate various service requirements, thereby making it more difficult to reduce the cost and period for software development. Further, since telecom carrier networks serve as basic social infrastructures, it is important to maintain their reliability and safety as a critical lifeline. Hence, ill-considered reduction of development costs and shortening of development period that could lead to decline in service quality must be avoided. In telecom carrier networks, communications softwares incorporate numerous quality improvement measures to prevent service interruptions during operation of public networks. The implementation of numerous quality improvement measures, however, has resulted in prolonged development periods and higher costs. To address these issues, we have been working on the automation of software development processes. Among the different processes in software development, testing yields the most influence in software quality. Test cases are therefore written by skilled engineers and are decided after multiple reviews, requiring a large amount of manpower in preparing them. Thoughtless reduction of these steps, however, could diminish software quality. We therefore used the knowhow of skilled engineers in writing test cases as training data to automate the generation of homogeneous test cases through machine learning. Our method automatically extracts homogeneous test cases that are not dependent on skills and knowhow of the engineer writing the test cases from requirements specification documents, which are the products of the basic design process in the past development. However, the required accuracy cannot be obtained by applying simple machine learning. The expansion of training data increases the cost and the quantity of requirement specification documents is limited, so it is necessary to improve the learning efficiency per unit training data. In this paper, we propose a method to increase accuracy by preparation of training data inputted into the machine learning process, and report the results of evaluation of effectiveness of the method.

Electrochemical impedance spectroscopy (EIS) is expected as a method to evaluate a polymer electrolyte membrane (PEM) water electrolysis cell. The internal state of electrolysis cell can be investigated by EIS without destruction. However, it may be difficult to measure stable impedance during electrolysis at high voltage since the large amount of oxygen is generated on the anode. Therefore, a short time impedance measurement is required. The purpose of this study is to develop short time impedance measurement method1,2) that can estimate the electrolyte membrane resistance R M and the charge transfer resistance R ct in a short time. A Japan Automobile Research Institute (JARI) standard cell with an electrode area of 25 cm2 was used as the test cell. The impedance measurement was performed in a frequency range from 100 mHz to 1 kHz and started from high frequency toward low frequency in the logarithmic scan. The Nyquist plot of impedance spectrum shows inductive behavior caused by wiring in the high frequency region and capacitive semicircle related to the anode in the middle frequency region. Under the condition of high current density, it was found that impedance spectrum was scattered in the low frequency range. The scattering originated from oxygen evolution at the anode when the measurement time is long. The measurement time was about 80 s to obtain an impedance spectrum, thus it is necessary to measure in a shorter time. Therefore, we obtained R ct in a short time by the two-point frequency method proposed by Haruyama et al.1,2) The equation (1) is used to calculate R ct. R ct = Re [Z] - R M + Im [Z]2/( Re [Z] - R M) (1) In the equation (1), R M is the electrolyte membrane resistance, which is the real component of the impedance at the high frequency. The real and imaginary parts of the impedance at the low frequency are represented by Re [Z] and Im [Z]. The measurement was performed by fixing the frequency at 1 kHz as a high frequency value and changing the low frequency value from 100 Hz to 10 mHz. R ct obtained from the measurement results by the two-point frequency method was compared with R ct obtained from the curve fitting of the impedance spectrum with the equivalent circuit. As a result, the relative error of the R ct calculated from the measurements at two frequencies 1 kHz and 10 Hz was -2.15% from the fitted result, and the measurement time was 5.33 s. From these results, it was found that the two-point frequency method was able to reduce the measurement time significantly compared to the normal EIS and to estimate R ct accurately. References 1) S. Haruyama, T. Tsuru, ASTM STP 727, ASTM Philadelphia, p.167 (1981). 2) T. Tsuru, S. Haruyama, Boshoku Gijutsu, 33, p.579-582 (1984).

Quantum dot sensitized solar cells (QDSSCs) have attracted much interest due to their theoretical efficiency, predicted to be as high as 44%. However, the energy conversion efficiency of QDSSCs is still a lot lower than the theoretical value, one reason for which is the number of surface defects on the QDs. In order to improve the conversion efficiency, surface passivation of the QDs has been applied to QDSSCs. Studying the mechanism of how the surface passivation influences the photoexcited carrier dynamics is very important. In this paper, we clarify the effects of CdS passivation on electron injection, trapping and recombination in CdS passivated PbS QDSSCs (called PbS/CdS double-layered QDSSCs). We found that electron trapping and recombination can be suppressed effectively, and that the electron injection efficiency can be increased significantly by surface passivation with CdS on PbS QDSSCs. Our findings provide a better understanding of the effects of surface passivation on QDSSCs, which will prove beneficial for making further improvements in the photovoltaic properties of QDSSCs.

Solid oxide fuel cells (SOFCs) with proton-conducting solid electrolyte, instead of the oxide-ion conducting solid electrolyte have attracted attentions because of their high potential to reduce operating temperatures and to enhance the electrical efficiencies of SOFCs. In addition, the proton-conducting SOFCs with multistage electrochemical oxidation configuration will be promising technology for critically-high electric efficiencies. However, it is known that there are non-negligible charge -carriers other than protons in typical proton-conducting solid oxide electrolytes at relatively high temperatures. The existence of the partial conductivities of holes and/or electrons will cause the internal leakage current that consumes fuel but never generates any electrical power output. The higher ratio of the leakage current to external current will more deteriorate the electrical efficiency. In this study, the effects of blocking -layers formed on the air side surface of base electrolyte layer consisting of BaZr0.8Y0.2O3−δ (BZY82) for suppressing the leakage current have been investigated by using electrochemical parameters of the partial conduction of the materials. The chemical potential profile and leakage current showed large dependence on the material of the blocking-layer. Lanthanum tungstate was found to play a role as unique and strong blocking-layer against the leakage current.

This paper proposes a pointing method named the Bring Your Own Pointer (BYOP). The BYOP enables an additional participation in a shared display collaboration and allows the users to point at the display simultaneously by using their own smartphones. A sticker application is developed to demonstrate the BYOP.

Radiofrequency ablation (RFA) has been accepted as safe and effective for treating early-stage hepatocellular carcinoma (HCC). However, it often causes severe pain. Therefore, in this study, we performed RFA under deep sedation and investigated its efficacy and safety. We conducted a retrospective study including 511 HCC patients who received approximately 886 RFA treatments between December 2014 and November 2016 at our institution. Respiratory depression was defined as oxygen saturation of below 90%; and severe body movement was defined as movement caused by pain, which was managed by lowering the power of the generator. Factors associated with respiratory depression and severe body movement were examined via univariate and multivariate regression analyses. Respiratory depression occurred in 15.3% of the patients and severe body movement in 26.5% of the patients. In the multivariate analysis, BMI (≥ 25 kg/m2, odds ratio [OR] = 1.75, P = 0.035) and longer ablation (≥ 10 min, OR = 2.59, P = 0.002) were significant respiratory depression-related factors. Male sex (OR = 2.02, P = 0.005), Child–Pugh class A (odds ratio = 1.96, P = 0.018), and longer ablation (≥ 10 min, OR = 3.03, P

In this paper, noting the effect of cavity bubble, which is also applied to the high-pressure operated washer, we have studied a spatial screen utilizing cavity bubble as a display of holographic projected images. Cavity bubble suggests a phenomenon such that the water boils and turns to the vapor by a sudden lowering of the pressure in the underwater and many small-sized bubbles are produced in the underwater. Here, to produce bubbles stably, we first dissolve the air in the water by imposing the high water-pressure, and then, pour it into the water-tank rapidly using the aspirator whose absorbing entrance is closed tightly. Like this way, by introducing a stable lowering process of the water-pressure, we may be able to produce a constant amount of bubbles continuously. In this report, we shall introduce a new process adopted a cavity bubble screen and study its effectiveness in the projecting process of holographic images. As this result, we have seen that a spatial screen utilizing cavity bubble will be expected to have a more improved quality in the brightness of the images than before in the display of the projected holographic images. This research was partially supported by the Grant-in-Aid for Scientific Research (No. 17K00493) in Japan.

Image-guided percutaneous ablation is considered best in the treatment of early-stage hepatocellular carcinoma (HCC). Ablation is potentially curative, minimally invasive, and easily repeatable for recurrence. Ethanol injection used to be the standard in ablation. However, radiofrequency ablation has recently been the most prevailing ablation method for HCC. Many investigators have reported that radiofrequency ablation is superior to ethanol injection, from the viewpoints of treatment response, local tumor curativity, and overall survival. New-generation microwave ablation can create a larger ablation volume in a shorter time period. Further comparison studies are, however, mandatory between radiofrequency ablation and microwave ablation, especially in terms of complications and long-term survival. Irreversible electroporation, which is a non-thermal ablation method that delivers short electric pulses to induce cell death due to apoptosis, requires further studies, especially in terms of long-term outcomes. It is considerably difficult to compare outcomes in ablation with those in surgical resection. However, radiofrequency ablation seems to be a satisfactory alternative to resection for HCC 3 cm or smaller in Child-Pugh class A or B cirrhosis. Furthermore, radiofrequency ablation may be a first-line treatment in HCC 2 cm or smaller in Child-Pugh class A or B cirrhosis. Various innovations would further improve outcomes in ablation. Training programs may be effective in providing an excellent opportunity to understand basic concepts and learn cardinal skills for successful ablation. Sophisticated ablation would be more than an adequate alternative of surgery for small- and possibly middle-sized HCC.

The interest in organometal trihalide perovskite (CH3NH3PbI3)-based solid-state hybrid solar cells has increased in recent years due to the high efficiencies achieved, with a record of over 20%, and the simple low temperature preparation method. Further improvements in the photovoltaic performance can be obtained by increasing the light harvesting in the NIR region up to 1000 nm. Recently, successful energy harvesting up to a wavelength of 1060 nm using Sn/Pb cocktail halide based perovskite materials has been achieved. However, the energy conversion efficiency of such solar cells (less than 10%) is much lower than that of CH3NH3PbI3 based solar cells, which is due to their lower open circuit voltage (Voc) and fill factor (FF). In order to improve this, we need to have a good understanding of the key factors governing the photovoltaic performance of these solar cells, i.e., the optical absorption, the charge separation and the recombination dynamics. Therefore, for this study, we characterized the optical absorption properties, including the bandgap and the Urbach energy, clarified the photoexcited carrier recombination dynamics in Sn/Pb cocktail perovskite (CH3NH3Sn0.5Pb0.5I3) and the charge separation and recombination dynamics at each interface in TiO2/Sn/Pb perovskite/P3HT solar cells, and lastly investigated the relationships between these and the photovoltaic performance.

In direct current (DC) system, there is no zero-cross of voltage curve, so that dangerous arc discharge shall be occurred inevitably between poles. Also, inrush current must be occurred in capacitors inside of ICT equipment. These unpreferable phenomenons will be happened at every movement of connect and disconnect. So, stable protection shall be necessary for human safety. New appliance coupler with safety functions to avoid damages of both inrush current and arc discharge has been developed and this paper explains its developed mechanism and reports the significant result of verification tests. There has never been industrial standard for appliance coupler of LVDC yet. Even in IEC, this is still on discussions. So, verification tests in this paper were performed compliant to IEC TS 62735-2 which was already published and specifies Plug and Socket-outlet of 400 Vdc for data centers.

Background Aggressive angiomyxoma (AAM) is a rare mesenchymal tumor that occurs almost exclusively in the soft tissue of the pelvis and perineum. AAM has both locally infiltrative and recurrent characteristics. Very few cases of AAM occurring outside of the pelvis and perineum have been reported. Here, we report a case of AAM originating in the liver of a 33-year-old female patient. Case presentation A 33-year-old woman underwent S8 subsegmentectomy after clinical diagnosis of a mucinous cystic neoplasm of the liver. Histological analysis revealed a tumor composed of spindle-shaped cells with vascular proliferation in a myxoid stroma. Immunohistochemically, the tumor cells stained positively for CD34, estrogen receptor (ER), and progesterone receptor (PgR) and negatively for S-100, EMA, CK19, CD99, HMB45, and α-smooth muscle actin. The tumor was diagnosed as AAM originating from the liver. The patient received no adjuvant chemotherapy. No sign of recurrence or distant metastasis has been noted for 10 months after the surgery. Conclusions We here report a second case of AAM originating from the liver, which is an uncommon location for this particular tumor.

Printed circuit boards for communication equipment have been promoted by mounting circuits in them with higher-density. It is said that an ECM (Electro Chemical Migration) generates in the insulating material when a high electric stress is applied to the board material under high temperature with high humid condition. Since the ECM degrades the insulation properties of it, it is necessary to use a suitable material for prevent the generation of ECM. However, while many research for the ECM in some traditional rigid circuit boards were carried out, there is a few reports about ECM in FPC (Flexible printed circuit). Which is usually used in many advanced recent electronic devices. Therefore we attempted to study the occurrence of the ECM in the FPC.

Recently we have developed the conceptual design for realizing a critically-high electrical efficiency with solid oxide fuel cells (SOFCs). SOFCs are promising electrochemical devices that enable the highest fuel-to-electricity conversion efficiencies under high operating temperatures. The concept of multi-stage electrochemical oxidation using SOFCs has been proposed and studied over the past several decades for further improving the electrical efficiency. However, the improvement is limited by fuel dilution downstream of the fuel flow. Recently we developed and reported a conceptual design that has a potential to realize a critically-high fuel-to-electricity conversion efficiency of up to as high as 85% (LHV, gross DC), in which a high-temperature multi-stage solid oxide fuel cells (SOFCs) is combined with a proton-conducting solid oxide electrolyte. Switching a solid electrolyte material from a conventional oxide-ion conducting material to a proton-conducting material under the high-temperature multi-stage electrochemical oxidation mechanism has proven to be highly advantageous for the electrical efficiency. The DC efficiency of 85% (LHV) corresponds to a net AC efficiency of approximately 77% (LHV), where the net AC efficiency refers to the transmission-end AC efficiency. This evolved concept will yield a considerably higher efficiency with a much smaller generation capacity than the state-of-the-art several tens-of-MW-class most advanced combined cycle (MACC). In the conceptual design the proton-conducting electrolyte was assumed to have a protonic transport number of 1. However, the protonic transport number of the proton-conducting solid oxide electrolyte depends on the material and operating conditions such as temperature, oxygen partial pressure, kinds of fuel and so on, and would affect the electrical efficiency. Therefore, to realize the critically-high electrical efficiency by using the multi-stage electrochemical oxidation, proton-conducting solid oxide having a high ionic transport number should be developed.

AIM To investigate the efficacy of prior minimal endoscopic sphincterotomy (EST) to prevent pancreatitis related to endoscopic balloon sphincteroplasty (EBS). METHODS After bile duct access was gained and cholangiogram confirmed the presence of stones < 8 mm in the common bile duct at endoscopic retrograde cholangiography, patients were subjected to minimal EST (up to one-third of the size the papilla) plus 8 mm EBS (EST-EBS group). The incidence of pancreatitis and the difference in serum amylase level after the procedure were examined and compared with those associated with 8-mm EBS alone in 32 patients of historical control (control group). RESULTS One hundred and five patients were included in the EST-EBS group, and complete stone removal was accomplished in all of them. The difference in serum amylase level after the procedure was - 25.0 (217.9) IU/L in the EST-EBS group and this value was significantly lower than the 365.5 (576.3) IU/L observed in the control group (P < 0.001). The incidence of post-procedure pancreatitis was 0% (0/105) in the EST-EBS group and 15.6% (5/32) in the control group (P < 0.001). CONCLUSION Prior minimal EST might be useful to prevent the elevation of serum amylase level and the occurrence of pancreatitis related to EBS.

A generation effect of higher harmonics for an externally applied signal in a photoconductive (PC) terahertz (THz)-wave emitter has been found. This effect is applicable to accurately measuring for frequencies of THz waves. This paper describes reasons why higher harmonics are generated in a PC device. The dependence of the photoconductance on the applied voltage in the PC device consists of a flat range and a negative slant range, and one sharply bending point is then formed at the boundary between the flat and slant ranges. When the PC device is irradiated by two laser beams with slightly different optical frequencies, the photoconductance is strongly modulated at the optical beat frequency in the THz region by photomixing the two laser beams. As a result, three bending points are formed in the average photoconductance (introduced as the average of the temporal photoconductance varying at the THz frequency). The slants comprised of the three bending points are different from each other. When the variation range of the applied voltage driven by the signal input on the biased voltage covers the voltage of one of the bending points, the photoconductance (or the average photoconductance in optical beating) varies along the different two slopes, the resultant temporal photocurrent is largely distorted, and then the harmonics of the signal input are generated in the photocurrent. The following features are clarified: (1) the harmonics of the signal input are generated by appropriately adjusting the bias voltage and the amplitude of the signal input, regardless of the presence/absence of optical beating; (2) the efficiency of the harmonic generation is about 10-4-10-5; and (3) the harmonics over 35th order with almost flat amplitudes (-3.8dB/octave) are generated.

A method for measuring frequencies of the terahertz (THz) radiation emitted by the antenna mounted on the photoconductive (PC) device is presented. Two laser beams with slightly different frequencies irradiate the PC device, producing a beat current of 1 THz in the photocurrent. A microwave signal is applied to the antenna electrode. The frequency of the THz wave is measured using the homodyne detection of the optical beat with the high-order harmonics of the microwave. It is being investigated that the high-order harmonics are produced by the PC device owing to its nonlinearity. Periodic peaks generated by the homodyne detection were observed in the photocurrent, as the microwave was swept from 16 to 20 GHz with a power of −40 dBm. Using the peak frequencies, the THz-wave frequency was determined to be 1 0 3 0 . 3 ± 3 . 7 3 GHz. The measurement error is estimated to be less than 0.43 GHz. The proposed method realizes a compact frequency meter in the THz region.

Two patients with isolated thalamic agraphia are described. Both showed kanji (Japanese morphograms) agraphia due to impaired character recall, grapheme deformity and micrographia (progressive reduction in character size during writing) after a lesion that involved the ventral lateral and ventroposterolateral nuclei. Single photon emission computed tomography with a (99m)Tc-ethylcysteinate dimer revealed hypoperfusion in the left precentral gyrus (Brodmann Area 6) and anterior supramarginal gyrus in both. Six months later, the extent of blood flow reduction decreased in the supramarginal gyrus in both patients and the precentral gyrus in patient 1. By this time, the writing impairment improved to nearly the normal range. Our study suggests that kanji agraphia (corresponding to lexical agraphia in Western countries) with poor grapheme formation and micrographia arises from a lesion in the ventral lateral and ventroposterolateral nuclei in the left thalamus. The accompaniment of poor grapheme formation and micrographia may reflect disruption of the cortico-subcortical motor circuit involving the putamen, thalamus, premotor cortex and sensorimotor cortex. It is also suggested that multiple cortical sites can be a target for secondary dysfunction that yields agraphia in a thalamic lesion, and that the recovery of reduced cortical blood flow does not always proceed in parallel with that of agraphia.