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ABSTRACTStarting with Hermann Maertens in Germany in the 19thcentury, urban designers have used rules of real-life perspective to position environmental objects with respect to the viewer. In a slow and intermittent evolution, they have engaged in ever more elaborate applications of such design, but have treated it as technique, neglecting theoretical investigation. The subject deserves new attention now that our lives are dominated ever more by electronic media, which may be atrophying our intuitive sense of space. The article investigates ideas of perspectival design through the 20thcentury, describes applications in urban design practice, points out flaws and limitations, responds to criticisms, and suggests theoretical directions.

Background: Internal hernia (IH) is one of the critical complications after gastrectomy with Roux-en-Y reconstruction, which can be prevented by closing mesenteric defects. However, only few studies have investigated the incidence of IH after laparoscopic total gastrectomy (LTG) with Roux-en-Y reconstruction for gastric cancer till date. This study aimed to assess the efficacy of defect closure for the prevention of IH after LTG. Methods: This multicenter, retrospective cohort study collected data from 714 gastric cancer patients who underwent LTG with Rou-en-Y reconstruction between 2010 and 2016 in 13 hospitals. We evaluated the incidence of postoperative IH by comparing closure and non-closure groups of Petersen’s defect, jejunojejunostomy mesenteric defect, and transverse mesenteric defect. Results: The closure group for Petersen’s defect included 609 cases, while the non-closure group included 105 cases. The incidence of postoperative IH in the closure group for Petersen’s defect was significantly lower than it was in the non-closure group (0.5% vs. 4.8%, p< 0.001). The closure group for jejunojejunostomy mesenteric defect included 641 cases, while the non-closure group included 73 cases. The incidence of postoperative IH in the closure group of jejunojejunostomy mesenteric defect was significantly lower than that in the non-closure group (0.8% vs. 4.1%, p= 0.004). Out of 714 patients, 41 underwent retro-colic reconstruction. No patients in the transverse mesenteric defect group developed IH. Conclusion: Mesenteric defect closure after LTG with Roux-en-Y reconstruction may reduce postoperative IH incidence. Endoscopic surgeons should take great care to prevent IH by closing mesenteric defects.

Background: Presently, there is no consensus as to what procedure of intracorporeal esophagojejunostomy (EJS) in totally laparoscopic total gastrectomy (TLTG) is best to reduce postoperative complications. The aim of this study was to demonstrate the superiority of linear stapled reconstruction in terms of anastomotic-related complications for EJS in TLTG. Methods: We collected data on 829 consecutive gastric cancer patients who underwent TLTG reconstructed by the Roux-en-Y method with radical lymphadenectomy between January 2010 and December 2016 in 13 hospitals. The patients were divided into two groups according to reconstruction method and matched by propensity score. Postoperative EJS-related complications were compared between the linear stapler (LS) and the circular stapler (CS) groups. Results: After matching, data from 196 patients in each group were analyzed. The overall incidence of EJS-related complications was significantly lower in the LS group than in the CS group (4.1% vs. 11.7%, p= 0.008). The incidence of EJS anastomotic stenosis during the first year after surgery was significantly lower in the LS group than in the CS group (1.5% vs. 7.1%, p= 0.011). The incidence of EJS bleeding did not differ significantly between the groups, although no bleeding was observed in the LS group (0% vs. 2.0%, p= 0.123). The incidence of EJS leakage did not differ significantly between the groups (2.6% vs. 3.6%, p= 0.771). Conclusion: The use of linear stapled reconstruction is safer than the use of circular stapled reconstruction for intracorporeal EJS in TLTG because of its lower risks of stenosis.

We investigated the superiority of docetaxel plus cisplatin and S-1 compared with cisplatin and S-1 in chemotherapy-naive patients with advanced gastric cancer.

Most wireless networks are specified as layer 2 (L2), or data link protocol. Recently, IoT and big data processing have promoted the use of wireless sensor networks to connect and send data to data center applications using the Internet. To do so, the implementation of an IP stack on the wireless node, or the gateway of the IP and wireless L2 network, has been proposed. Both approaches are developed to allow the application on the IP network to access L2 wireless network nodes. However, since wireless sensor networks do not require any network protocol, an IP is not essential for collecting data. Therefore, we propose a novel bridging VPN for connecting wireless networks, in which the application and wireless end nodes are not required to acknowledge an IP address or network protocol. In this way, the IP network merely serves to transport the data link frames of wireless networks. We believe that this is another style of IoT, and recommend a small IoT businesses and institutions for use of this VPN as a test bed before they start to implement an IP stack on their systems.

AbstractWe consider a finite-time optimal consumption problem where an investor wants to maximize the expected hyperbolic absolute risk aversion utility of consumption and terminal wealth. We treat a stochastic factor model in which the mean returns of risky assets depend linearly on underlying economic factors formulated as the solutions of linear stochastic differential equations. We discuss the partial information case in which the investor cannot observe the factor process and uses only past information of risky assets. Then our problem is formulated as a stochastic control problem with partial information. We derive the Hamilton–Jacobi–Bellman equation. We solve this equation to obtain an explicit form of the value function and the optimal strategy for this problem. Moreover, we also introduce the results obtained by the martingale method.

The coronavirus disease 2019 (COVID-19) pandemic has restricted many medical practices. We aimed to investigate the impact of the COVID-19 pandemic on the number of bronchoscopies, outpatients, and hospital admissions. We retrospectively analyzed the number of outpatients, admissions, and bronchoscopies performed between March 2020 and May 2022. We defined “Peak month of the pandemic,” “Wave of the pandemic,” “Month in the wave,” and “Period of a state of emergency” for each analysis. In the first year of the COVID-19 pandemic, analysis of variance (ANOVA) in linear mixed models indicated significant effects of “month in each wave” on the number of bronchoscopies (P= .003), outpatients (P= .041), and admissions (P= .017). The number of outpatients, admissions, and bronchoscopies was significantly influenced by the first wave of the COVID-19 pandemic. In contrast, in the second year of the COVID-19 pandemic, a mixed-ANOVA indicated significant effects of “month in each wave” only on the number of outpatients (P= .020) but no significant effects on the number of bronchoscopies (P= .407) and admissions (P= .219). During the second year of the pandemic, the number of bronchoscopies and admissions was not significantly affected by the waves of the pandemic. There were no significant differences in the number of admissions and bronchoscopies between the fourth and sixth waves. Although the number of bronchoscopies was found to be significantly affected in the early stages of the COVID-19 pandemic, the impact of the pandemic was much more limited thereafter.

Pneumothorax is a known sequela of coronavirus disease 2019 (COVID-19). However, the clinical features of pneumothorax associated with COVID-19 have not been fully elucidated.

Diffusion of photoexcited carriers and the subsequent thermal diffusion by photoexcitation of a nanoparticulate TiO2thin film were observed by the heterodyne transient grating (HD-TG) method. The observed HD-TG signal showed that the photoexcited carriers were generated inhomogeneously in the depth direction and they diffused both in the depth and parallel directions of the film. The diffusion processes were analyzed using a two-dimensional diffusion model. The thermal profile generated by the relaxation of the photoexcited carriers was treated by the same model. It was found that the effective diffusivities of the photoexcited carriers and heat decreased as the size of the nanoparticles in the film increased. It is suggested that the transport properties of the photoexcited carriers and heat are dominated by the inter-particulate resistance.

Abstract: Background: This study aims to evaluate the clinical and anatomical factors, particularly pelvic dimensions that influence the difficulty of performing laparoscopic anterior resection for rectal cancer. Methods: We studied 50 consecutive patients who underwent laparoscopic anterior resection with double-stapling technique (DST) anastomosis for rectal cancer between January 2006 and February 2010. Staging was performed by computed tomography. Five pelvic dimensions (anteroposterior and transverse diameters of pelvic inlet and outlet, and pelvic depth) were measured using three-dimensional volume-rendering images. We also examined a number of other clinical characteristics, including gender, history of laparotomy, body mass index (BMI), operator, tumor location, tumor depth, nodal involvement, and tumor diameter. Univariate and multivariate analyses were performed to determine the predictive significance of these variables on surgical difficulty based on operative time and intraoperative blood loss. Results: Males had significantly shorter pelvic inlets and outlets and significantly greater pelvic depth than females. However, gender did not significantly affect surgical outcomes, although males did tend to experience greater blood loss. Maximum tumor diameter (p = 0.014), BMI (p = 0.001), operator (p < 0.001), and tumor location (p = 0.009) were independent predictors of operative time, which, in turn, was related to intraoperative blood loss (p < 0.001). Conclusions: Maximum tumor diameter, BMI, operator experience, and tumor location can be used to predict the operative time required to complete laparoscopic anterior resection with DST anastomosis for rectal cancer, with no correlations between pelvic dimensions and operative time. The difficulty of the procedure was not related to patients’ pelvic dimensions, which led us to conclude that “narrow pelvis” is not a contraindication for this surgery. Based on these results, we suggest that laparoscopic anterior resection should be performed by experienced surgeons in patients with large tumors, high BMI, and/or extraperitoneal rectal cancer.

Abstract: Background: Laparoscopic surgery for rectal cancer is unpopular because it is technically challenging. Suitable training systems have not been widely studied or established despite the steep learning curve for this procedure. We developed a systematic training program that enables resident surgeons to perform laparoscopic low anterior resection (LLAR) for rectal cancer and evaluated the safety and feasibility of this training program. Methods: We analyzed prospectively gathered data on all LLARs for rectal cancer performed at a single center over a 7-year period. Patients were assessed for demographic characteristics, tumor characteristics, operative procedure, operative time, blood loss, conversion to open surgery, complications, time to bowel recovery, distal margin, and number of lymph nodes harvested. We compared the early surgical, oncological, and functional outcomes of LLARs performed by expert surgeons with those of LLARs performed by resident surgeons for both intraperitoneal and extraperitoneal rectal cancer. All analyses were performed on an intention-to-treat basis. Results: A total of 137 patients met the inclusion criteria for this study. Of the 75 LLARs for intraperitoneal rectal cancer, 40 were performed by expert surgeons (I-E group) and 35 by resident surgeons (I-R group). Of the 62 LLARs for extraperitoneal rectal caner, 51 were performed by expert surgeons (E-E group) and 11 by resident surgeons (E-R group). The operative time was longer in the E-R group than in the E-E group. The time to resumption of diet was longer in the I-E group than in the I-R group. The other early outcomes, including blood loss, anastomotic leakage, conversion to open surgery, and number of lymph nodes harvested, were similar in the I-E and I-R groups and in the E-E and E-R groups. Conclusion: Our systematic training program on LLAR for rectal cancer enables resident surgeons to perform this procedure safely early during residency, with acceptable short-term outcomes.

Background. We evaluated the effects of human atrial natriuretic peptide (hANP) during cardiopulmonary bypass (CPB).

Objective:Even when left internal thoracic artery flow is very low, we have used the artery for grafting without any further maneuvers. In this study, we investigated the clinical results of coronary bypass surgery using the left internal thoracic artery with low free flow. Methods:A total of 163 patients were divided into 2 groups: group L (n = 43) had free flow of 20 mL/min or less and group H (n = 120) had free flow of more than 20 mL/min. We performed a comparative study on the basis of coronary angiography and pulsed Doppler echocardiography. Furthermore, 12 months’ postoperative graft angiography was carried out in 11 patients from group L. Results:No patient had low output syndrome or perioperative myocardial infarction. One month after the operation, 3 cases of graft occlusion and 9 cases of the “string sign” were identified in group H. However, group L had no graft occlusion and only 1 case of the “string sign.” The 1-month postoperative Doppler echocardiographic study showed no significant differences in the diastolic fraction of velocity time integrals and the diastolic/systolic peak velocity ratio of the grafts. In the 11 patients undergoing angiography after 1 year, graft patency was excellent. Moreover, the graft diameter was significantly larger than it was 1 month after the operation. Conclusion:These results suggest that the left internal thoracic artery can be used for coronary artery bypass grafting even when the flow is less than 20 mL/min. (J Thorac Cardiovasc Surg 2000;119:125-9)

Interrupted aortic arch type A with aortopulmonary window was diagnosed in a 12-day-old neonate. A successful one-stage repair was undertaken through a midline sternotomy without circulatory arrest. The aortopulmonary window was closed through the anterior wall of communication between ascending aorta and main pulmonary artery with a patch. Position of the arterial cannula was changed during the repair, which made it possible to mobilize and expose the aortic arch for the completion of direct anastomosis.

Abstract: From October 1982 to the present, 16 patients have been supported by a pneumatic ventricular assist device (VAD). Since April 1990, we have introduced a venoarterial bypass (VAB) with percutaneous cardiopulmonary support (PCPS) system. This PCPS system was used in 12 patients. The long‐term survival rate of PCPS cases (41%) was much better than that of VAD cases (19%). The main cause of death in VAD cases was multiple organ failure (MOF). Although VAB was initiated more recently than VAD, the duration on support was longer in the VAD group than in the VAB group. Because of the longer support duration and the presence of many patients with MOF, coagulopathy deteriorated more readily in the VAD group than in the VAB group. In the case of postcardiotomy cardiopulmonary bypass weaning or low‐output syndrome (LOS), the VAB with PCPS system should be applied first under intraaortic balloon pumping assist because of its simplicity and low cost. Thereafter, VAD should be applied in cases refractory to VAB support.