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Following curative liver resection (LR), resectable tumor recurrence in patients with preserved liver function leads to deciding between a repeat LR and a salvage liver transplantation (LT), if a donor's liver is available. This retrospective study compared survival outcomes and recurrence pattern following salvage living donor LT (LDLT) and repeat LR in patients with recurrent hepatocellular carcinoma (HCC). We reviewed the medical records of patients who underwent repeat LR (n = 163) or LDLT (n = 84) for recurrent HCC following curative resections, between January 2005 and December 2017 at a single institution. A 1:1 propensity score matching led to 42 patients per group. Disease-specific and recurrence-free survival were significantly better in the salvage LDLT group than in the repeat LR group (p = .042; HR = 2.40; 95% CI, 0.69-6.00 and p < .001; HR = 4.23; 95% CI, 2.05-8.71, respectively). Despite significant differences in recurrence patterns between the two groups (p = .019), the patient death rates, after recurrence, were similar for both groups (p = .760). This study indicates that salvage LDLT is superior to repeat LR for treating patients with transplantable, intrahepatic HCC recurrence, even in patients with Child-Pugh class A liver cirrhosis.

The lack of plant-side energy storage analysis to support nuclear power plants (NPP), has setup this research endeavor to understand the characteristics and role of specific storage technologies and the integration to an NPP. The paper provides a qualitative review of a wide range of configurations for integrating the energy storage system (ESS) to an operating NPP with pressurized water reactor (PWR). The role of ESS technologies most suitable for large-scale storage are evaluated, including thermal energy storage, compressed gas energy storage, and liquid air energy storage. The methods of integration to the NPP steam cycle are introduced and categorized as electrical, mechanical, and thermal, with a review on developments in the integration of ESS with an operating PWR. By adopting simplified off-design modeling for the steam turbines and heat exchangers, the results show the performance of the PWR steam cycle changes with respect to steam bypass rate for thermal and mechanical storage integration options. Analysis of the integrated system characteristics of proposed concepts for three different ESS suggests that certain storage technologies could support steady operation of an NPP. After having reviewed what have been accomplished through the years, the research team presents a list of possible future works.

The term squamoid cyst of pancreatic ducts (SCOP) has been proposed recently, and it is a very rare benign lesion. We report a case of SCOP in a patient who underwent laparoscopic distal pancreatectomy. A 51-year-old woman presented with a pancreatic cystic lesion (3.3 cm) as an incidental finding on abdominal ultrasonography. A computed tomography scan showed a well-defined cystic lesion in the body of the pancreas with peripheral nodular calcification. Histology showed a unilocular cyst with a thin, fibrotic wall, and it was surrounded by normal-appearing pancreatic tissue. The lining of the cyst was composed of stratified non-keratinized squamous epithelium without significant nuclear atypia. Immunohistochemistry showed positive nuclear p63 expression in the cyst lining. The final diagnosis of SCOP was established. It is important to distinguish SCOPs from mucinous pancreatic cysts that have malignant potential. Preoperative diagnosis of SCOP is still difficult, and further studies are needed to identify specific preoperative characteristics that can accurately distinguish this lesion.

Organic light-emitting diode (OLED) microdisplays have attracted much attention as displays for small form factor augmented reality (AR) devices. To realize glass-like thin and wide field of view (FoV) AR devices, we designed a display module with a high aspect ratio microdisplay and a thin optical component. For the high aspect ratio microdisplay, we developed the color OLED microdisplay with a 32:9 aspect ratio and a 0.8-inch diagonal ∼2,490-ppi CMOS backplane. To express color and reduce optical crosstalk, we fabricated the color filter (C/F) patterning directly on the white OLED. We also developed a pin mirror lens with 11 pin mirrors to improve the optical efficiency and quality with a thin lens. By combining the microdisplay with LetinAR’s pin mirror lens, we successfully demonstrated an AR device with a wide horizontal FoV of 46° but with a small form factor 4 mm lens.

Limb-shaking transient ischemic attack is a rare disease, associated with the steno-occlusion of the internal carotid artery. It is caused by hemodynamic dysfunction in the anterior circulation. It is difficult to observe patients directly in clinical settings since they visit the hospital after symptoms have subsided which usually last less than 5 minutes. Here we report a atient who developed right arm dominant myoclonus related to left internal carotid artery occlusion along with a recorded video.

Co-combustion of bunker-C oil and bio-heavy oil for power generation provides a strategic way for mitigating the environmental burdens (climate change) due to the intrinsic carbon neutrality of bio-heavy oil. Prior to the co-combustion process, the high content of Na and K in heavy oil should be removed for the operational safety. Given that the washing process has been currently practiced for metal removal, it is desirable to develop the chemical-free washing process. Note that H2SO4 was commonly used during the washing process. To this end, this study laid great emphasis on the possible use of CO2 for the washing process. To increase the removal efficiency of Na and K, this study particularly employed micro-/nano-sized CO2 bubbles. To access the in-depth insights, a computational fluid dynamics (CFD) simulation was conducted prior to a lab-scale experimental work. The CFD simulation suggests that CO2 bubbling expedited the mixability during the washing process. Also, the CFD simulation suggested that the CO2 bubbling effects could be enhanced because the high viscosity of bio-heavy oil cancelled out the buoyancy force. A lab-scale experimental work was also in good agreement with the CFD simulation. In the presence of CO2 bubbles, 80% of Na and K was removed when the volumetric ratio of water and bio-heavy oil was 8. Even under the volumetric ratio condition of 0.125, the metal removal efficiency was not substantially reduced. Thus, all experimental findings signify that metal removal by micro-/nano-sized CO2 bubbling should be done by a cascade system.

A nuclear power plant is one of the power sources that shares a large portion of base-load. However, as the proportion of renewable energy increases, nuclear power plants will be required to generate power more flexibly due to the intermittency of the renewable energy sources. This paper reviews a layout thermally integrating the liquid air energy storage system with a nuclear power plant. To evaluate the performance realistically while optimizing the layout, operating nuclear power plant conditions are used. After revisiting the analysis, the optimized performance of the proposed system is predicted to achieve 59.96% of the round-trip efficiency. However, it is further shown that external environmental conditions could deteriorate the performance. For the design of liquid air energy storage-nuclear power plant integrated systems, both the steam properties of the linked plants and external factors should be considered.

From the very first time that graphene was used as a transparent electrode for OLED applications, the emergence of active-matrix (AM)-graphene OLED displays has been envisioned. Realizing this expectation, however, turned out to be difficult. Two obstacles are the growth and transfer of a large-area graphene film and the patterning of a graphene film into pixels. To solve these problems, a process of patterning a graphene film without surface contamination was developed. The fabrication of OLED panels by the patterned graphene anode on Gen 2(370 × 470 mm)-sized and flexible substrates was successfully demonstrated. In this work, oxide TFT arrays were combined as a switching backplane, and a pixelated graphene OLED was used as an emissive layer, to realize AM-graphene OLED displays. To explore the technical feasibility of flexible AM-graphene OLED displays, the aforementioned components were formed on a flexible substrate. For commercial-level production, all the processes that were used were chosen to be compatible with the conventional display processes.

Microdisplay is a key technology for realizing augmented reality (AR) and mixed reality (MR) devices, which have attracted much attention of late. Even though the operating voltage in the tandem structure is higher than that in the single structure, 2-stack tandem OLED exhibited 20,000 cd/m2 at 9 V, which is compatible with CMOS circuit driving. Due to its top-emitting geometry with a tandem structure, the OLED device with a well-controlled thickness exhibited a white spectrum with (0.26, 0.26) color coordinates. The pixel density of the fabricated microdisplay panel with a white tandem OLED was about 2350 pixels per inch, and the active area of the panel was 0.7 inch diagonally. The resolution of the panel was 1280 × 1024, corresponding to SXGA, and the maximal luminance was 3,000 cd/m2.

Although the current nodal staging system for gallbladder cancer (GBC) was changed based on the number of positive lymph nodes (PLN), it needs to be evaluated in various situations. We reviewed the clinical data for 398 patients with resected GBC and compared nodal staging systems based on the number of PLNs, the positive/retrieved LN ratio (LNR), and the log odds of positive LN (LODDS). Prognostic performance was evaluated using the C-index. Subgroups were formed on the basis of an restricted cubic spline plot as follows: PLN 3 (PLN = 0, 1–2, ≥ 3); PLN 4 (PLN = 0, 1–3, ≥ 4); LNR (LNR = 0, 0–0.269, ≥ 0.27); and LODDS (LODDS

Operation with reduced number of operators is considered as an important operational mode to improve economics of a nuclear power plant (NPP) in the future and it will be more important for the small modular reactors (SMRs). To control NPPs efficiently and safely with a reduced number of operators, an intelligent operation system can be very useful. However, reduced number of operators will result in larger consequence in human error due to simultaneous multi-unit failures are now more probable than the conventional operational mode. Thus, to decrease the probability of human error occurrence for the reduced number of operators, the development of an autonomous operation system with certain level of intelligence is inevitable. The prediction capability of system’s behavior as well as understanding the root cause for the current situation should be an essential function of the designed autonomous operation system. The authors propose to use the current system thermal–hydraulic (STH) analysis code platform to develop such intelligence. As a demonstration of the suggested method, the authors used the STH code to track the accident initiator of both large pressurized water reactor (PWR) and SMR. The discussions on how this method can be useful for future NPP operation and how generic differences in system design actually influence the system behavior are presented.

We investigated the optical reflectance, surface roughness, and sheet resistance of aluminum (Al)/titanium nitride (TiN), titanium (Ti), and tungsten (W) layers on Si substrates, which are available in the CMOS foundry, for organic light-emitting diode (OLED) microdisplays. The devices with different metal anode layers exhibited different hole-injection properties and OLED performances, owing to the different optical and electrical properties of metal anode layers. Based on the OLED characteristics, the Al/TiN layer was selected as an anode layer for OLED microdisplays. A green monochromatic OLED microdisplay panel was designed and implemented using the 0.11-μm CMOS process. The density of pixels was ~2 351 pixels per inch and the panel's active area was 0.7 in in diagonal. The resolution of the panel was 1 280 × 3 × 1 024, corresponding to SXGA. The panel was successfully operated, and the maximal luminance was ~460 cd/m2.

Air pollution sensors based on organic transistors have attracted much interest recently; however, the devices suffer from low responsivity and slow response and recovery rates for gas analytes. These shortcomings are attributed to the low charge-carrier mobility of organic semiconductors and to a structural limitation resulting from the use of a thick and continuous active layer. In the present work, we investigated the material properties of a multiscale porous zeolitic imidazolate framework, [Zn(2-methylimidazole)2]n (ZIF-8), and examined its potential as an analyte channel material inserted at an organic-transistor active layer. A series of carbonized zeolitic imidazolate frameworks (ZIFs) were prepared by thermal conversion of ZIF-8 and also studied for comparison. The microstructures, morphologies, and optical/electrical characteristics of polythiophene/ZIF-8 hybrid films were systematically investigated. Organic-transistor-type nitrogen dioxide sensors based on the polythiophene/ZIF-8 hybrid films showed substantially improved sensing properties, including responsivity, response rate, and recovery rate. The electrical conductivity of the carbonized ZIF-8s enhanced the field-effect mobility of the organic transistors; however, the sensing performance was not improved, because of the closed pore structures resulting from the carbonization. These results provide invaluable information and useful insights into the design of transistor-type gas sensors based on organic semiconductor/metal-organic framework hybrid films.

Objective To evaluate the distribution of multiple anterior bridging bone (ABB) patterns using a newly designed interbody cage with 4 anterior holes that enable communication between the inside and outside of the cage and to estimate its mechanical effect by finite element analysis (FEA). Methods Patients underwent single-level lumbar interbody fusion using ABB cages. Two raters evaluated the distribution patterns of ABB on computed tomography scans 1 year after surgery. We defined the term H-fusion as the presence of complete anterior extracage and intracage bone bridging, with ≥1 ABBs between them. We performed finite element analysis to investigate the effect of ABB on maximal stiffness. Results The study enrolled 98 patients. ABB was most frequently observed in the medial hole of the cages (73.7%). The mean number of ABBs was 3.65, and H-fusion was observed at 135 levels (34%). Postoperative improvement in the Oswestry Disability Index was significantly higher in patients who achieved interbody fusion and H-fusion than in patients who did not. As ABB was added, the increment in the relative maximal stiffness was most affected under flexion and extension forces. Conclusions We observed an average of 3.65 complete ABBs. Finite element analysis demonstrated that ABB could increase the stability in fused segments, especially under flexion and extension stress. Our results suggest that the ABB cage, which allows communicating cross-bridging between inside and outside of the cage, may facilitate a more stable fusion process than a conventionally designed cage.

Aberrant donor hepatic artery anatomy or hepatic artery injury during organ procurement or recipient preparation poses a surgical challenge during deceased donor liver transplantation. In this study, we aimed to investigate arterial reconstruction using microvascular techniques during deceased donor liver transplantation and suggest reasonable indications for the microsurgical approach in this setting. We retrospectively reviewed the outcomes of 470 deceased donor liver transplantations performed at our institution between July 2011 and December 2015. Of these, 128 recipients underwent microsurgical hepatic artery reconstruction and 342 underwent reconstruction with surgical loupes. Thirty-two patients (6.8%) experienced hepatic artery-related complications, including hepatic artery thrombosis (n = 8, 1.7%). In the propensity score-matched cohort, the surgical loupe group showed a higher complication rate (P = .782). On multivariate analysis, cold ischemia time (odds ratio, 0.995; 95% confidence interval, 0.9920-0.999; P = .009) and use of aortohepatic conduits (odds ratio, 5.254; 95% confidence interval, 1.878-14.699; P = .002) were independent predictors of arterial complications. The low incidence of hepatic artery complications in this study is likely attributable to the active application of microsurgical techniques. Active application of back-table microsurgical plasty and selective application of microsurgical techniques for main arterial reconstruction may help minimize operative difficulties and arterial complications.

Study Design: Prospective observational study. Objectives: We aimed to analysis the distributional patterns of the intra- and extra-cage bridging bone (InCBB and ExCBB) and the significance of ExCBB using suggested lumbar interbody fusion criterion. Methods: This study included the patients with planned single-level transforaminal lumbar interbody fusion. We divided bridging bone into InCBB (in void of right or left cage) and ExCBB (outside of cages; anterior, posterior, intermediate, right, or left) and graded bridging scores from 0 to 2 on postoperative 1-year computed tomography. The fusion was defined as at least having one or more graded 2 and the evaluation were conducted twice by 2 raters. Results: Sixty-five patients were enrolled. All values of intra- and inter-rater reliability in left InCBB, anterior, and posterior ExCBB showed good agreements (≥0.75). Both InCBBs showed similar mean bridging scores (Rt:1.43 vs Lt:1.48), and in ExCBBs, the anterior was the highest (1.43), followed by the posterior (1.14); the right and left were the lowest (0.49 and 0.52 respectively). In subjects determined as fusion (85.4%), complete bridging was observed more in ExCBB (88.8%) than in InCBB (69.9%). Conclusions: Given the higher bridging scores in both InCBBs and Ant. ExCBB, bone grafting is important promoting factor to increase the interbody bridging bone regardless of outside or in void of cages. Based on our suggested criterion, ExCBB has a greater proportion compared to InCBBs for determining the fusion and extra-cage bone grafting should be considered as important procedures for interbody fusion.

Lecture Surgery is the gold standard for treatment in patients with resectable colorectal liver metastasis (CRLM), with reported 5-year survival rates ranging from 40% to 60%. Unfortunately, only 10%-25% of patients with CRLM are considered eligible for liver resection (LR). In others, extensive tumor burden within the liver or poor anatomical position of the tumors close to critical vascular or biliary structures precludes resection. In these patients, systemic therapy is offered with the goal of improving survival or potentially converting patients into surgical resection candidates. Although the outcome of systemic treatment is still being improved, the realistic goal of systemic treatment remains palliative. It is for this reason that more aggressive local therapeutic approaches are being pursued in patients with unresectable CRLM. Over recent decades, many efforts have been made to increase the potentially resectable pool of patients with CRLM. The advent of more effective chemotherapy, specific techniques such as portal vein embolization, local ablation therapy, and two-stage hepatectomy have expanded the indications for surgery in patients with CRLM, and have offered a substantial survival benefit to selected patients. Although radiofrequency ablation (RFA) was initially used as a safe, well tolerated, easily repeated and less invasive technique in patients with unresectable CRLM, its indication has been expanded to those with resectable CRLM. However, unlike in HCC, the therapeutic efficacy of RFA in CRLM remains controversial, especially in patients with resectable tumors. Numerous studies have reported that RFA was inferior to LR in the treatment of CRLM, in terms of both local control and survival. In essence, there is little evidence to support the routine use of RFA in the management of CRLM, even in combination with LR [1,2]. (1) Role of RFA in resectable CRLM At present, no prospective randomized trials have been reported. However, there are some retrospective reports of large numbers of patients regarding RFA versus LR for CRLM. Some reported that patients who received RFA had survival rates comparable to surgical group while others found that survival rates were better among patients undergoing LR. These benefits have led to the question of whether RFA could be used in the treatment of resectable patients as well, and whether the oncologic outcomes would be equivalent. Further studies are necessary to determine the efficacy of RFA versus LR. The COLLISION trial is an ongoing phase III randomized trial comparing RFA and LR on patients with small (< 3 cm) CRLM. Another ongoing trial, the LAVA trial, has also been designed to compare LR and RFA for the patients with CRLM. These new randomized trials might provide more evidence for the present equivalent outcome [3,4]. (2) Role of RFA in unresectable CRLM Systemic chemotherapy is the standard of care for patients with unresectable CRLM. However, liver metastatic lesions typically respond poorly to chemotherapy alone; thus, survival outcomes are suboptimal despite the recent introduction of novel chemotherapeutic agents and targeted therapies. Several clinical studies demonstrated that RFA is an effective and safe treatment for CRLM; however, local and distant recurrent rates remain high. The combination of RFA and systemic chemotherapy has also been evaluated in some clinical studies and resulted in promising outcomes for CRLM as demonstrated by progression-free survival (PFS) and overall survival (OS). However, the treatment outcome of treated patients is still heterogenous. To deliver evidence on the beneficial effect of such an aggressive approach, RCT was required. To date, one randomized control trial has investigated the use of RFA for CRLM: A European intergroup randomized phase III study (European Organization for Research and Treatment of Cancer 40004 CLOCC trial). This trial randomized 119 patients with unresectable CRLM to receive either systemic chemotherapy alone (n = 59) or systemic chemotherapy plus RFA with or without LR (n = 60). At the time of primary analysis with a median follow-up time of 4.4 years, the median OS was 45.3 (95% confidence interval [CI], 33.1-NA) months for RFA combined with chemotherapy and 40.5 (95% CI, 29.5-50.1) months for chemotherapy alone (hazard ratio [HR] = 0.74; 95% CI, 0.46-1.19; p = 0.22). Median PFS was 16.8 months (95% CI, 11.7-22.1) in the group assigned to combination treatment and 9.9 months (95% CI, 9.3-13.7) in the group assigned to chemotherapy alone (HR = 0.63; 95% CI, 0.42-0.95; p = 0.025) [5]. After an extended follow-up of 9.7 years, the median OS was 45.6 months (95% CI = 30.3-67.8 months) for the RFA + chemotherapy arm and 40.5 months (95% CI, 27.5-47.7 months) for the chemotherapy alone arm (HR = 0.58; 95% CI = 0.38-0.88; p = 0.01). As previously reported, PFS was statistically significantly prolonged in the combined RFA with chemotherapy arm as compared with the chemotherapy alone arm (HR = 0.57; 95% CI, 0.38-0.85; p = 0.005) [6]. These data strongly suggest that the combined modality of aggressive local tumor treatment in combination with systemic chemotherapy can change the outcome of these patients considerably with a clear benefit on overall survival. (3) Combined intraoperative RFA and LR Patients who have multiple bilobar CRLM may be candidates for a two-stage approach. Another therapeutic option for patients with multiple CRLM can involve the combination of LR and RFA. RFA and LR should not be mutually exclusive. However, most published data on CRLM and RFA have focused on outcomes comparing patients who exclusively underwent either LR versus RFA alone. The data on combining LR with RFA for the treatment of multiple CRLM have been more limited. Some comparative studies demonstrated that combination of RFA and LR provided worse survival compared to LR alone. Others showed comparable survival compared to LR alone. Until now the outcome of treatment in the literature are very heterogenous [7,8]. Conclusion The evidence so far in the literature has shown that RFA is insufficient to be recommended as a radical oncological treatment of CRLM. However, RFA has established its position in patients with unresectable but ablatable CRLM with EORTC-CLOCC trial. When complete resection cannot be achieved, selective use of RFA can provide a modest survival benefit over chemotherapy alone. Combination of RFA and LR can be considered as a viable option to expand resectable pool in selected patients with multiple bilobar CRLM.

Laparoscopic living donor hepatectomy for transplantation has been well established over the past decade. This study aimed to assess its safety and feasibility in pediatric living donor liver transplantation (LDLT) by comparing the surgical and long-term survival outcomes on both the donor and recipient sides between open and laparoscopic groups. The medical records of 100 patients (≤17 years old) who underwent ABO-compatible LDLT using a left lateral liver graft between May 2008 and June 2016 were analyzed. A total of 31 donors who underwent pure laparoscopic hepatectomy and their corresponding recipients were included in the study; 69 patients who underwent open living donor hepatectomy during the same period were included as a comparison group. To overcome bias from the different distributions of covariables among the patients in the 2 study groups, a 1:1 propensity score matching analysis was performed. The mean follow-up periods were 92.9 and 92.7 months in the open and laparoscopic groups, respectively. The mean postoperative hospital stay of the donors was significantly shorter in the laparoscopic group (8.1 days) than in the open group (10.6 days; P < 0.001). Overall, the surgical complications in the donors and overall survival rate of recipients did not differ between the groups. Our data suggest that the laparoscopic environment was not associated with long-term graft survival during pediatric LDLT. In addition, the laparoscopic approach for the donors did not adversely affect the corresponding recipient's outcome. Laparoscopic left lateral sectionectomy for living donors is a safe, feasible, and reproducible procedure for pediatric liver transplantation.

Due to small footprint and high efficiency, a Supercritical CO2 (S-CO2) power cycle is considered to be one of the promising next-generation power cycles. Although S-CO2 is reported as a powerful cleaning agent, the performance of a power system operating with S-CO2 will also inevitably degrade over time. Previous researchers have shown that turbomachinery deterioration could be a major subject regarding the system performance degradation. Nevertheless, no quantitative evaluation has yet been made so far. In this study, the impact of the performance degradation of the S-CO2 turbomachinery on the overall performance of the system is analyzed quantitatively. The concept of Health Parameter is used to simulate turbomachinery degradation. To quantify the impact, an S-CO2 direct-cycle small modular reactor is selected as a target system. A transient analysis platform is built using a nuclear system safety analysis code and the deep neural network (DNN)-based S-CO2 turbomachinery off-design performance model. System dynamics are evaluated for primary frequency control ability and secondary load-following capability. Results show that the control problems during the transient state can occur when the output fluctuations are large and the performance degradation is severe. It has been confirmed that even control failures of the PID controllers can occur. Therefore, the performance degradation of turbomachinery must be monitored and considered, for an operation strategy for S-CO2 systems.

Background Secondary biliary cirrhosis (SBC) represents a unique form of cirrhosis that develops in the liver secondary to persistent biliary obstruction. This study aimed to review the living donor liver transplants (LDLTs) performed at our center for patients with SBC and end-stage liver disease and to share the perioperative strategies undertaken to achieve satisfactory outcomes. Methods The medical records of 29 patients who underwent LDLT for SBC between December 1994 and July 2018 at the Asan Medical Center (Seoul, South Korea) were retrospectively reviewed. Their clinical data were extracted and statistically analyzed. Survival curves were computed. Results The perioperative and in-hospital morbidity rates were 72.4% and 10.3%, respectively. The overall mean recipient follow-up was 80.0 (SD, 66.4) months (range, 0.8-246.8 months). Patient survival rates after 1, 3, 5, and 10 years after transplant were 82.8%, 79.3%, 79.3%, and 79.3%, respectively. For liver grafts, the survival rates were 82.8%, 75.8%, 75.8%, and 75.8% at 1, 3, 5, and 10 years, respectively. Conclusions LDLT is potentially a final lifesaving resort for patients with SBC with portal hypertension. However, considering the difficulty of surgery and perioperative management, LDLT should be performed by experienced transplant surgeons in a center where a multidisciplinary approach is possible.

The ability to image pressure distribution over complex three-dimensional surfaces would significantly augment the potential applications of electronic skin. However, existing methods show poor spatial and temporal fidelity due to their limited pixel density, low sensitivity, or low conformability. Here, we report an ultraflexible and transparent electroluminescent skin that autonomously displays super-resolution images of pressure distribution in real time. The device comprises a transparent pressure-sensing film with a solution-processable cellulose/nanowire nanohybrid network featuring ultrahigh sensor sensitivity (>5000 kPa−1) and a fast response time (1000 dpi) pressure imaging without the need for pixel structures. Our approach provides a new framework for visualizing accurate stimulus distribution with potential applications in skin prosthesis, robotics, and advanced human-machine interfaces., Electronic skin that spatially maps pressure distribution through imaging shows limited performance despite improvements to data acquisition. Here, the authors report ultraflexible, transparent electroluminescent skin capable of high-resolution imaging of pressure distribution over 3D surfaces.

Background Vertebral fragility fracture (VFF) is a common fracture related to osteoporosis. However, VFF might be asymptomatic and often occurs in patients without osteoporosis. Therefore, we investigated the characteristics of age-related VFF and their correlation with bone mineral density (BMD). Furthermore, we analyzed other factors affecting VFF Methods Medical records from a single center were retrospectively reviewed for 2,216 patients over 50 years old with vertebral fractures conservatively treated from 2005 to 2016. Patients' age, gender, body mass index (BMI), BMD, fracture level, previous vertebral fractures, and anti-osteoporosis medications were obtained. Patients were divided into fragility/non-fragility groups and age sub-groups. The odds ratio for VFF in relation to BMD was evaluated. We also identified other predictive factors for VFF by age groups. Results The fragility group had a higher women ratio, older age, lower BMI, lower BMD, and greater incidence of previous vertebral fractures than the non-fragility group. VFFs were seen in 41.18% of normal BMD patients aged 50–59 and 67.82% of those aged 60–69. The proportion of VFFs increased with age in all WHO osteoporosis classifications. Patients with osteopenia and osteoporosis were 1.57 and 2.62 fold more likely to develop VFFs than normal BMD. In the younger group (under 70), age, women, BMD, and previous vertebral fracture were significant factors affecting VFF, and in the older group (70 and over), age, women, and BMD were factors. In the fragility group, anti-osteoporosis medication rates were 25.08% before and 45.96% after fracture. Conclusion Considerable VFFs occurred in the younger age groups without osteoporosis and age itself was another important predictor of VFF especially in older age groups. The discrepancy between the incidence of VFF and BMD suggests the necessity of supplemental screening factors and anti-osteoporosis treatment guidelines using only BMD should be reconsidered., Graphical Abstract

This chapter delineates the technical issues and integration scheme related to the use of graphene as a transparent electrode in organic light–emitting diode (OLED) applications. We address fundamental issues related to the use of graphene electrode in OLED. Later, we deal with patterning of graphene films into pixels on array scale and their integration into OLED panels. In this course, we emphasize the importance of strong adhesion of graphene film to its support and geometrically correct patterning. Finally, we demonstrate a fully operational two-color OLED module and a flexible OLED module. Our results signify the technical possibility of using graphene films as actual components in commercial OLED products.

The significant increase of renewable energy source is expected to induce stability issue of electric grid due to the intermittency of renewable energy. The challenge of intermittency is making energy storage system more important. Among the grid-scale energy storage systems, a Liquid Air Energy Storage System is increasingly popular with its high energy density, long expected service lifetime, less operation and maintenance cost, and less geographical constraint. At the same time, flexibility of nuclear power plant is becoming more important with higher penetration of renewable energy sources. However, load-following operation not only causes safety issues on the fuel integrity, but also leads to economic deterioration of nuclear power plant. In this study, the new concept is suggested by mechanically integrating nuclear steam cycle and liquid air energy storage system to achieve high flexibility and economy of a nuclear power plant. At off peak hour, nuclear energy is stored by bypassing steam from nuclear steam cycle to external steam turbine which mechanically connected to air compressor in the liquid air energy storage system. Air is compressed by air compressor and liquefied by cold energy storage system. At peak hours, the stored energy is recovered by evaporating and expanding. The thermodynamic and economic analyses are conducted on standalone liquid air energy storage system and nuclear integrated liquid air energy storage system to further examine the benefits of the proposed system. The results show that the round-trip efficiency of the proposed system is around 51% and the energy density is 116 kWh/m3. The round-trip efficiency is competitive and the energy density is superior to other grid-scale energy storage system. Also, the integration improves the capacity factor of nuclear power plant by 3%p. The Levelized Cost of Electricity shows $219.8/MWh for standalone liquid air energy storage system and $182.6/MWh for nuclear integrated liquid air energy storage system, reducing 17% of the standalone systems’ cost. The results show that the proposed concept can achieve better economy than using standalone liquid air energy storage system as well as other energy storage systems. In conclusion, the proposed nuclear integrated liquid air energy storage system has very good potential to become a competitive energy storage option and can assist to stabilize the future electricity grid with high reliance on renewable energy.

A solar-nuclear hybrid system that combines Concentrating Solar Power (CSP) and nuclear power was suggested previously to meet the electricity demands for remote microgrids. The hybrid system combines CSP, Thermal Energy Storage (TES) and a Micro Modular Reactor (MMR). A Supercritical Carbon dioxide (sCO2) power system is used for power generation system. CSP, which has relatively high efficiency, no refueling, low operation and installation costs, is suitable as an energy source for the microgrid. However, since it is challenging to meet 100% electricity demand with a standalone CSP system due to excessive energy storage system and large land area requirement, a hybrid system is proposed by adding a nuclear system to resolve this issue. The hybrid system showed a higher capacity factor than the standalone CSP system while reducing the required energy storage. However, the TES capacity was still excessive to meet 100% of the electricity demand in the previous study to overcome seasonal variation. Therefore, in this study, the hybrid system is re-designed by optimizing solar to nuclear ratio while tracing change in the Levelized Cost Of Electricity (LCOE) of the system. A sensitivity analysis is performed with respect to the five variables; nuclear to solar heat ratio, direct normal irradiation, peak-to-average electricity demand ratio, nuclear island cost, discount rate affecting LCOE. As a result of economic evaluation, it is confirmed that the hybrid system is cost competitive to the standalone CSP system. This study showed that the nuclear-CSP hybrid system can be utilized as a power source with a high potential for isolated microgrid.

The new application of phase change material for passively cooling the containment building of a nuclear power plant provides many benefits such as minimized wall penetration, low maintenance cost, and the possibility of installation in currently operating power plants with a minimal design change. In this study, the applicability of PCM as a passive containment cooling system is verified through design and evaluation of the PCM condenser. In addition, the effective heat capacity method is verified for simulating the melting process of PCM in the condition of a reactor accident. The PCM condenser design is optimized with five design parameters; melting point, volume, heat transfer area, effective thermal conductivity, and total heat absorbed. The performance of the PCM condenser is evaluated by containment safety analysis and is compared to that of an active containment cooling system. Although the PCM condenser had a limitation for absorbing only a fixed amount of thermal energy due to the absence of an external heat sink, the PCM condenser shows better performance in the early stage after the accident initiation compared to the single spray system and finally maintains the integrity of the containment building.

The enhancement of the luminance of organic light-emitting diode (OLED) panels with various areas (2.25–6084 mm2) using a microlens array (MLA) film was investigated. The luminance enhancement was dependent on the viewing angle, and the largest enhancement (64%) was observed in the normal direction while 60 and 18% enhancements were observed at 60 and 30°, which led to lower enhancement (38%) of the total luminous flux compared with the luminance enhancement (64%) in the normal direction. The luminance enhancement with the MLA film also depended on the panel area, and the smaller panels showed lower luminance enhancement than the larger ones. As for the small panels, the straying light beyond the panel areas significantly affected the luminance of the panels, and over 60% luminance enhancement was observed in the normal direction for the large panels (2500 and 6084 mm2) with the MLA film while only 48 and 58% luminance enhancements were observed at the small panels (2.25 and 70 mm2).

Presented is a flexible dual-mode display operable in reflective and emissive mode according to ambient light for optimal visibility on a nonplanar surface. Flexible-backplane-embedding organic light-emitting diodes (OLEDs), thin-film transistors (TFTs), and control electrodes for liquid crystal (LC) shutter are realized by the laser lift-off (LLO) method and the newly developed polyimide (PI) delamination technique. A novel color-filterless LC shutter with color dyes is merged with this flexible backplane for operation in reflective mode. This work opens up a promising approach to building displays that are adaptive to the surrounding environment for better usability.

After the Fukushima accident, the importance of an emergency power supply for a nuclear power plant has been emphasized more. In order to maximize the performance of the existing emergency power source in operating nuclear power plants, adding a waste heat recovery system for the emergency power source is suggested for the first time in this study. In order to explore the possibility of the idea, a comparison of six supercritical carbon dioxide (S-CO2) power cycle layouts recovering waste heat from a 7.2 MW alternate alternating current diesel generator (AAC DG) is first presented. The diesel engine can supply two heat sources to the waste heat recovery system: one from exhaust gas and the other from scavenged air. Moreover, a sensitivity study of the cycles for different design parameters is performed, and the thermodynamic performances of the various cycles were evaluated. The main components, including turbomachinery and heat exchangers, are designed with in-house codes which have been validated with experiment data. Based on the designed cycle and components, the bottoming S-CO2 cycle performance under part load operating condition of AAC DG is analyzed by using a quasi-steady state cycle analysis method. It was found that a partial heating cycle has relatively higher net produced work while enjoying the benefit of a simple layout and smaller number of components. This study also revealed that further waste heat can be recovered by adjusting the flow split merging point of the partial heating cycle.

A new structure for a switchable mirror device based on reversible electrodeposition is proposed. This device does not contain Cu ions in the electrolyte and adapts a counter electrode. The feasibility of the device was evaluated with a WO3 film, which is a well-known electrochromic material, as a counter electrode. Even in the absence of Cu ions, the WO3 film facilitates a clean erase feature in the device. Furthermore, using a pre-deposited Ag film as a working electrode, Ag deposition can be driven at a substantially lower voltage than that in conventional devices. Moreover the deposition current decreases with the progress of Ag deposition, and stops after completion of the deposition process. The results clearly indicate that the tri-bromine ion, which makes the self-erasing circulation, is not generated during Ag deposition process. The new switchable mirror shows excellent bistability and size scale-up is possible because it does not consume continuous current in the mirror state. By appling the proposed technology, a switchable mirror device with a 7 cm × 9 cm active area was successfully fabricated.

This report proposes a new approach to evaluate the odour nuisance of cattle manure samples from three different cattle breeds ( i.e. , native cattle, beef cattle, and milk cow) by means of quantification and speciation of volatile fatty acids (VFAs). To this end, non-catalytic esterification thermally induced in the presence of a porous material (silica) was undertaken, and the optimal operational parameters such as the derivatizing temperature (330 °C) for the maximum yield (≥ 99 ± 0.4%) of volatile fatty acid methyl esters (VFAMEs) were established. Among the VFA species in cattle manure based on quantification of VFAs, the major species were acetic, butyric and valeric acid. Considering the odour threshold of each VFA, our experimental results suggested that the major contributors to odour nuisance were C 4–5 VFA species ( i.e. , butyric and valeric acid). Hydrothermal treatment was performed at 150 °C for 0–40 min to correlate the formation of VFAs with different types of cattle feed formulations. Our experimental data demonstrated that the formation of total VFAs is linearly proportional to the hydrothermal treatment duration and the total content of VFAs in native cattle, beef cattle, and milk cow manure samples reached up to ~ 1000, ~ 3200, and ~ 2800 ppm, respectively. Thus, this study demonstrated that the degree of VFA formation is highly dependent on cattle feed formulations, which rely significantly on the protein content. Furthermore, the hydrothermal treatment provides a favourable condition for generating more VFAs. In this context, producing cattle manure into refused derived fuel (RDF) via a hydrothermal treatment is not a viable option to control odour.

With increasing demand for transparent conducting electrodes, graphene has attracted considerable attention, owing to its high electrical conductivity, high transmittance, low reflectance, flexibility, and tunable work function. Two faces of single-layer graphene are indistinguishable in its nature, and this idea has not been doubted even in multilayered graphene (MLG) because it is difficult to separately characterize the front (first-born) and the rear face (last-born) of MLG by using conventional analysis tools, such as Raman and ultraviolet spectroscopy, scanning probe microscopy, and sheet resistance. In this paper, we report the striking difference of the emission pattern and performance of transparent organic light-emitting diodes (OLEDs) depending on the adopted face of MLG and show the resolved chemical and physical states of both faces by using depth-selected absorption spectroscopy. Our results strongly support that the interface property between two different materials rules over the bulk property in the driving performance of OLEDs.

To meet the energy requirement for a remote and isolated region, a concept of supercritical CO 2 (S-CO 2 ) cooled micro modular reactor (MMR) has been developed, which is easy to transport by fully modularizing the nuclear power system. From the previous work, only the on-design performances of MMR were presented. However, since the nuclear system needs to meet high safety standard, the design can be finalized only after the evaluation of the nuclear system response under multiple transient conditions. Such transient conditions may include part load operation and postulated accidents. The system response can be evaluated only with a high fidelity computer simulation, since it is almost impossible to construct a nuclear facility to test at such conditions. The simulation is performed to guarantee its autonomous operability and safety. Unfortunately, a system analysis computer code available for the S-CO 2 cycle analysis is yet to be developed for the MMR safety evaluation. Description of a S-CO 2 system analysis code platform is first presented in this paper. After that, the developed code is validated with experimental data. The steady state of MMR is first modeled with the code, which is followed by simulations of part load operation and postulated accidents of MMR. All simulation results show that the current design of MMR has the ability to maintain its safety and structural integrity even under extreme conditions to protect the public from radiation hazard at all times.

Here in this study, the genuine role of CO2 in co-pyrolysis of swine manure and coal was mainly investigated to increase the thermal efficiency of the thermo-chemical process. The TGA test of swine manure and coal revealed that the CO2 co-feeding impact on any reactions (≤740 °C) between CO2 and the sample surface (i.e., heterogeneous reaction) should be excluded. A batch-type co-pyrolysis revealed two genuine CO2 co-feeding impacts on co-pyrolysis of swine manure and coal. First, CO2 can be an additional source for C and O through a plausible reaction between pyrolytic oil and CO2, which led to the enhanced generation of CO by the conversion of volatile organic carbons (VOCs) evolved from thermal deconstruction of pyrolytic substrate. Second, CO2 expedite the thermal cracking of VOCs, which also resulted in the more generation of H2 and CH4. Two genuine roles of CO2 in co-pyrolysis of swine manure and coal occurred independently. All experimental findings will be directly applicable to the gasification process since pyrolysis is an intermediate step for the gasification.

This paper presents the neutronics and transient studies of a supercritical CO2-cooled micro modular reactor (MMR). The suggested MMR is an extremely compact, integrated, and truck-transportable reactor with 36.2 MWth power and a 20-year lifetime without refueling. A salient feature of the MMR is that all the components including the generator are contained in a small reactor vessel. For a minimum volume and maximum lifetime of the MMR core, a fast neutron spectrum is utilized. To improve the fuel-coolant compatibility and to maximize the fuel volume fraction, UC fuel is considered. A unique replaceable fixed absorber (RFA) is also introduced in order to maintain the excess reactivity at less than 1 dollar during the whole operational period. A drum-type reactivity control system is adopted in the MMR as the primary control system to prevent a control rod ejection accident and a single absorber rod located at the core center is used as the secondary ultimate shutdown system. The neutronics analysis is performed by using the continuous energy Monte Carlo code Serpent with the ENDF/B-VII.1 library. In addition, an unprotected loss of flow (ULOF) accident is simulated by the system analysis code GAMMA+ to show the passive safety of the MMR system.

As the share of renewable energy will be increasing, there is a growing interest in flexible power sources and energy storage systems due to the intermittent nature of renewable energy. We propose the Energy Storage System (ESS) integrated Nuclear Power Plant (NPP) as a solution. The system operates on load-following by branching the mass flow from the steam cycle to the ESS without changing the reactor thermal output. However, the merging point can be different for heat storing ESS and work storing ESS because the outlet conditions of the ESS vary depending on the type of ESS. In this study, the merging points are categorized into two types, feedwater heater and condenser. At each merging point, cycle optimization is performed while increasing the branch flow into ESS. The optimization goal is to maintain the feedwater temperature at the inlet of a steam generator. The power output and energy delivered to the ESS according to the merging point are estimated. From this study, it was found that when 25% of the inlet mass flow rate to the low-pressure turbine is diverted to ESS, the overall output of the steam cycle is decreased by 44.17% for the heat conversion ESS and 49.95% for the work conversion ESS.

In this paper, a thermodynamic study of newly suggested supercritical carbon dioxide (s-CO2) cycle layouts using an isothermal compressor is presented. The isothermal compressor is conceptually defined using the ‘infinitesimal approach’ in attempt to resolve the ambiguity in its performance framework. As part of preliminary investigation, the isothermal compressor is demonstrated thermodynamically, and the calculations highlight that it reduces the compression work significantly under s-CO2 power cycle operating conditions over other representative working fluids. The in-house code is modified to allow the analysis of three s-CO2 cycle layouts, simple recuperated Brayton cycle, recompression Brayton cycle, and partial heating Brayton cycle, adopting the isothermal compressor. The cycle performance is evaluated through a sensitivity analysis of cycle design parameters, pressure ratio and flow split ratio. When the machinery is applied, the cycle net efficiency of the simple recuperated cycle and the recompression cycle is improved by 0.5% point and 1–3% points, respectively. Moreover, the partial heating cycle layout, known for its outstanding performance in waste heat recovery applications as a bottoming cycle, produces 15–18% more net work when using an isothermal compressor, compared to the reference cycle. Overall, the use of the isothermal compressor not only improves the general cycle performance, but also provides another degree of freedom for cycle design optimization of s-CO2 cycles.

Background Tumor location is a prognostic factor for survival in patients with T2 gallbladder cancer. However, the optimal extent of resection according to tumor location remains unclear. Methods We reviewed the records of 192 patients with T2 gallbladder cancer who underwent R0 or R1 resection at 6 institutions. Perioperative and oncologic outcomes were compared according to the extent of resection between hepatic-sided ( n = 93) and peritoneal-sided ( n = 99) tumors. Results After a median follow-up of 30 months, the 5-year overall survival (84.9% vs 71.8%, P = .048) and recurrence-free survival (74.6% vs 62.2%, P = .060) were greater in peritoneal-sided T2 patients than in hepatic-sided T2 patients. Among hepatic-sided T2 patients, the 5-year overall survival was greater in patients who underwent radical cholecystectomy including lymph node dissection with liver resection than in patients who underwent lymph node dissection without liver resection (80.3% vs 30.0%, P = .032), and the extent of liver resection was not associated with overall survival ( P = .526). Lymph node dissection without liver resection was an independent prognostic factor for overall survival in hepatic-sided T2 gallbladder cancer (hazard ratio 5.009, 95% confidence interval 1.512–16.596, P = .008). In peritoneal-sided T2 patients, the 5-year overall survival was not significantly different between the lymph node dissection with liver resection and the lymph node dissection without liver resection subgroups (70.5% vs 54.8%, P = .111) and the extent of lymph node dissection was not associated with overall survival ( P = .395). Conclusion In peritoneal-sided T2 gallbladder cancer, radical cholecystectomy including lymph node dissection without liver resection is a reasonable operative option. Radical cholecystectomy including lymph node dissection with liver resection is suitable for hepatic-sided T2 gallbladder cancer.

Non-Hodgkin lymphoma often involves the liver. However, primary hepatic lymphoma (PHL) confined to the liver without evidence of lymphomatous involvement is rare. The optimal therapy for PHL is still unclear. Most patients present with poor prognostic features. Here, we report a case of PHL treated with liver resection followed by chemotherapy. A 65-year-old male was referred for further evaluation about a liver mass detected on ultrasound. Abdominal computed tomography (CT) scan showed well-defined single mass of 6 cm in diameter. Positron emission tomography/CT scan revealed a hot uptake lesion on the segment 8 of the liver. Colonoscopy showed no abnormal finding. It was diagnosed as intrahepatic cholangiocarcinoma. A right anterior sectionectomy was performed. Postoperative pathology revealed diffuse large B-cell lymphoma. Bone marrow biopsy showed normal findings. The final diagnosis was confirmed as PHL. The patient subsequently received six cycles of R-CHOP (Rituximab, Cyclophosphamide, Doxorubicin, Vincristine, and Prednisolone) regimen. The patient is doing well without relapse after 60 months of follow-up. Because of its rarity and the lack of specific laboratory, radiological, or clinical finding, liver biopsy is essential for definite diagnosis of PHL. Optimal treatment for PHL is currently uncertain. However, surgical resection followed by adjuvant chemotherapy should be considered for select individuals to achieve better outcome.

In a sodium-cooled fast reactor, a sodium-water reaction (SWR) could be occurred at pressure boundaries between the two separated systems, the steam Rankine cycle and the sodium coolant system, which results in a serious problem in the system. Since it has been a design challenge for researchers, as an alternative system, the supercritical CO 2 (S-CO 2 ) Brayton cycle was suggested. To utilize the S-CO 2 Brayton cycle to a SFR, a series of studies on the coupled system have been conducted at Korea Atomic Energy Research Institute (KAERI). The studies were mainly focused on the pressure boundary failure events and their consequences including Na-CO 2 reactions. Prior to the experimental studies, the authors classified the reaction behaviors of Na-CO 2 reaction based on the possible scenarios that could take place at pressure boundaries. Through experimental studies, it was found that the reaction follows typical chemical formulas and it is essentially dependent on the reaction temperature. More importantly, the reaction rate changed drastically at the specific temperatures and the reaction became flammable exceeding a certain temperature. To specify the design conditions of the SFR system coupled with the S-CO 2 Brayton cycle, by means of a dedicated set-up the self-ignition temperature has been evaluated. Exceeding this threshold temperature a significant increase in the reaction speed is observed. We setup an experimental apparatus and a test matrix based on one of possible scenarios where the flammable Na-CO 2 reaction takes place and we installed a visualized chemical reactor to watch reaction phenomenon around the self-ignition temperature. The experimental apparatus was designed to be easy to control heaters, to regulate gas supply, and to measure reaction temperature. Through the experiment, it was found that the flammable temperature of Na-CO 2 reaction lies between 598.3˚C and 599.9˚C and how liquid sodium reacts with gaseous carbon dioxide at these temperatures. The results will be help to set design criteria for the pressure boundary and it will take long time but an appropriate safety system would be introduced.

Organic wrinkle structures are investigated as an internal scattering layer for the fabrication of highly efficient organic light-emitting diodes (OLEDs). The solution-processed wrinkle structures are planarized with a high-index layer, resulting in a reduced surface roughness and optical haze simultaneously. The OLED device including the wrinkle structures achieved external quantum efficiency (EQE) of 24.2%, corresponding to a 1.24 time enhancement with respect to that of a control device having no internal scattering layer. By attaching a micro lens array (MLA) or a half ball lens (HBL) on the external surface of the substrate, the proposed device exhibits an EQE of 30.5% (1.56 time enhancement) and 41.8% (2.14 time enhancement), respectively. Randomness of the distributed wrinkle structures is shown to provide additional benefits of reduced angular spectral distortion and Lambertian-like emission properties. Trans-scale optical simulation combining wave-optics and the geometrical effect are used for the quantitative analysis of the emission characteristics of the device.

To realize transparent organic light-emitting diodes (OLEDs), a top electrode should have excellent optical, electrical, and mechanical properties. Conventionally, transparent conductive oxides and semitransparent metal have been widely used for transparent top electrodes, but they have several fundamental drawbacks. We herein report efficient large-area inverted transparent OLEDs using a vacuum-laminated top electrode with an embedded metal mesh. The laminated device with 1 mm pitch exhibits superior optical properties including a high transmittance of 75.9% at 550 nm, a low reflectance of 12.0% at 550 nm, and spectrally flat characteristics over the entire visible region and shows nearly ideal Lambertian angular emission characteristics with little angular color shift in both directions. Moreover, the lowered sheet resistance of 4 Ω/sq originating from the embedded metal mesh (1 mm pitch) led to efficient and uniform emission characteristics. As a result, the device shows a relatively high maximum curre...