Although laparoscopic donor hepatectomy is increasingly common, few centers with substantial experience have reported the results of pure laparoscopic donor right hepatectomy (PLDRH). Here, we report ...the experiences of 60 consecutive liver donors undergoing pure laparoscopic donor hepatectomy (PLDH), with most undergoing right hepatectomy. None of the 60 donors who underwent PLDH had intraoperative complications and none required transfusions, reoperation, or conversion to open hepatectomy. Forty‐five donors who underwent PLDRH between November 2015 and December 2016 were compared with 42 who underwent conventional donor right hepatectomy (CDRH) between May 2013 and February 2014. The total operation time was longer (330.7 vs 280.0 minutes; P < .001) and the percentage with multiple bile duct openings was higher (53.3% vs 26.2%; P = .010) in the PLDRH group. However, the length of postoperative hospital stay (8.4 vs 8.2 days; P = .495) and rate of complications (11.9% vs 8.9%; P = .733) and re‐hospitalizations (4.8% vs 4.4%; P = 1.000) were similar in both groups. PLDH, including PLDRH, is feasible when performed by a highly experienced surgeon and transplant team. Further evaluation, including long‐term results, may support these preliminary findings of comparative outcomes for donors undergoing PLDRH and CDRH.
Compared with the open approach, pure laparoscopic donor hepatectomy, primarily right hepatectomy, is a feasible procedure when performed by a highly experienced surgeon and transplantation team.
Following noncurative endoscopic resection of early gastric cancer (EGC), the patient should be observed when the underlying disease is severe, the patient is elderly, or the patient refuses further ...treatment. The aim of this study was to analyze the clinical outcomes of patients with differentiated EGC who underwent noncurative endoscopic resection without additional treatment.
Included patients underwent noncurative endoscopic resection for differentiated EGC without additional treatment at the Asan Medical Center between July 1994 and January 2009. Clinical and oncological outcomes were analyzed.
A total of 159 patients were included in the analysis. The median follow-up period was 33 months (interquartile range IQR 22 - 52 months). In total, 40 patients died (25.2 %) - 3 due to stomach cancer, 34 due to other causes, and 3 from unknown causes; the median survival time after endoscopic treatment for these patients was 27.5 months (IQR 13.8 - 48.3 months). Multivariate analysis showed that the rates of underlying disease (P < 0.001) and lymphovascular invasion (P = 0.005) were higher among the 40 patients who died than among the 119 survivors. The overall 3- and 5-year survival rates were 82.9 % and 77.1 %, respectively; the rates of the patients with lymphovascular invasion were 61.9 % and 42.4 %, respectively, and the rates of patients without lymphovascular invasion were 86.1 % and 81.8 %, respectively (P < 0.001).
Additional treatment provides fewer benefits to patients who do not have long life expectancies. Additional surgery can be considered for patients with lymphovascular invasion because of its high mortality rate; however, the benefits and risks of surgery should be considered carefully.
Reactor experiment for neutrino oscillation (RENO) began data-taking from August 2011. It successfully observed reactor antineutrino disappearance in April 2012 to measure the smallest mixing angle ...of θ13. Two identical detectors, one at near location and the other at far location, are constructed at the Yonggwang nuclear power plant in South Korea, to compare the observed reactor neutrino fluxes. Each RENO detector is filled with 16 mass tons of Gadolinium loaded liquid scintillator (GdLS) in the neutrino target region, and with 28 mass tons of unloaded liquid scintillator (LS) in the γ-catcher region surrounding the target. LS was developed to satisfy chemical, physical, optical properties, and safety requirements. Linear alkyl benzene (LAB) was chosen as a solvent because of its high flash-point, sufficient light yield, and being environmentally friendly. GdLS is carefully developed to keep a long attenuation length and high light yield for a long time period. In this paper, we report the characteristics and mass production of the RENO LS and GdLS.
The Fourth Industrial Revolution incorporates the digital revolution into the physical world, creating a new direction in a number of fields, including artificial intelligence, quantum computing, ...nanotechnology, biotechnology, robotics, 3D printing, autonomous vehicles, and the Internet of Things. The artificial intelligence field has encountered a turning point mainly due to advancements in machine learning, which allows machines to learn, improve, and perform a specific task through data without being explicitly programmed. Machine learning can be utilized with machining processes to improve product quality levels and productivity rates, to monitor the health of systems, and to optimize design and process parameters. This is known as smart machining, referring to a new machining paradigm in which machine tools are fully connected through a cyber-physical system. This paper reviews and summarizes machining processes using machine learning algorithms and suggests a perspective on the machining industry.
Vibrational modes in the terahertz (THz) frequency range are good indicators of lead halide perovskite’s crystallization phase. We performed real-time THz spectroscopy to monitor the crystallization ...kinetics in the perovskite films. First, THz absorptance was measured while the perovskite film was annealed at different temperatures. By analyzing the Avrami exponent, we observed an abrupt dimensionality switch (from 1D to 2D) with increasing temperature starting at approximately 90 °C. We also monitored the laser-induced crystallinity enhancement of the preannealed perovskite film. The THz absorptance increased initially, then subsequently decayed over a couple of hours, although the enhancement factor varies depending on the film crystallinity. In particular, the Avrami analysis implied that the light-induced crystallization was assisted by the 1D diffusion processes. The activation photon energy was measured at 2.3 eV, which indicated that enhanced crystallization originated from the photoinduced structural change of residual lead iodide at the grain boundary.
Although endoscopic submucosal dissection (ESD) is increasingly utilized to treat early neoplasms of the gastrointestinal tract, its use for duodenal neoplasms is limited by the thin wall and narrow ...lumen of the duodenum. We have reviewed cases where ESD was used to treat sessile, nonampullary duodenal neoplasms. To do this, we retrospectively reviewed the medical records of patients treated with ESD for adenomas of the duodenum from January 2001 to December 2010, assessing the curative outcomes and complication rates. A total of 14 cases were reviewed. Mean patient age was 56.4 years. The mean size of tumors and mean size of the specimens were 17.1 mm and 26.4 mm, respectively. The en bloc resection rate with ESD was 78.6%, and the complete (R0) resection rate was 85.7%. No patient in the study experienced major bleeding. However, second-look endoscopy revealed minor bleeding requiring endoscopic homeostasis in one case (7.1%). Perforations were observed in five cases (35.7%). Two of the five patients with perforation underwent surgery. The ESD methods yielded acceptable curative resection rates for duodenal adenomas, although ESD was associated with a higher rate of perforation. Therefore, duodenal ESD should be performed with care and only in selected patients to avoid serious complications.
In patients with coronary artery disease who are being evaluated for percutaneous coronary intervention (PCI), procedures can be guided by fractional flow reserve (FFR) or intravascular ...ultrasonography (IVUS) for decision making regarding revascularization and stent implantation. However, the differences in clinical outcomes when only one method is used for both purposes are unclear.
We randomly assigned 1682 patients who were being evaluated for PCI for the treatment of intermediate stenosis (40 to 70% occlusion by visual estimation on coronary angiography) in a 1:1 ratio to undergo either an FFR-guided or IVUS-guided procedure. FFR or IVUS was to be used to determine whether to perform PCI and to assess PCI success. In the FFR group, PCI was to be performed if the FFR was 0.80 or less. In the IVUS group, the criteria for PCI were a minimal lumen area measuring either 3 mm
or less or measuring 3 to 4 mm
with a plaque burden of more than 70%. The primary outcome was a composite of death, myocardial infarction, or revascularization at 24 months after randomization. We tested the noninferiority of the FFR group as compared with the IVUS group (noninferiority margin, 2.5 percentage points).
The frequency of PCI was 44.4% among patients in the FFR group and 65.3% among those in the IVUS group. At 24 months, a primary-outcome event had occurred in 8.1% of the patients in the FFR group and in 8.5% of those in the IVUS group (absolute difference, -0.4 percentage points; upper boundary of the one-sided 97.5% confidence interval, 2.2 percentage points; P = 0.01 for noninferiority). Patient-reported outcomes as reported on the Seattle Angina Questionnaire were similar in the two groups.
In patients with intermediate stenosis who were being evaluated for PCI, FFR guidance was noninferior to IVUS guidance with respect to the composite primary outcome of death, myocardial infarction, or revascularization at 24 months. (Funded by Boston Scientific; FLAVOUR ClinicalTrials.gov number, NCT02673424.).
In order to investigate the possible use of methane (CH4)-ammonia (NH3) blends as a low carbon fuel, the combustion characteristics of expanding spherical premixed CH4-NH3/air flames are studied, ...measuring and predicting their laminar burning velocities (SL∞), Markstein numbers (Ma) and structure. Results show that the premixed CH4-NH3/air flames are thicker and propagate slower than the pure CH4/air flames, with reduced carbon dioxide (CO2) emissions. Meanwhile, both flames are cellularly stable for the present various test conditions, showing 0.3 < Ma < 2.1, and this observation is weakly affected by the concentration of NH3 in the fuel blend. Moderate reduction in SL∞, i.e., reasonable burning intensity for practical applications, of the CH4-NH3/air flames even with reduced CO2 emissions supports the possible use of CH4-NH3 blends as a low carbon fuel. However, the problem of high local nitrogen oxides (NOx) emissions in the present flame configuration should be resolved for their practical application. The quantitative discrepancies between the measurements and predictions for a few conditions despite their generally and qualitatively good agreement indicate that a new mechanism optimized for the oxidation of CH4-NH3 blends at atmospheric condition is needed since no reaction mechanism for it is currently available.
•Potential of CH4-NH3 blends as a low carbon fuel has been demonstrated.•Premixed CH4-NH3/air flames exhibit remarkable reduction of CO2 emissions.•Premixed CH4-NH3/air flames show moderate reduction in laminar burning velocity.•Premixed CH4-NH3/air flames are cellularly stable for various test conditions.•Practical methods to reduce enhanced NOx emissions with NH3 addition are needed.
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