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The visualization of accurate colour information using quantum dots has been explored for decades, and commercial products employing environmentally friendly materials are currently available as backlights1. However, next-generation electroluminescent displays based on quantum dots require the development of an efficient and stable cadmium-free blue-light-emitting device, which has remained a challenge because of the inferior photophysical properties of blue-light-emitting materials2,3. Here we present the synthesis of ZnSe-based blue-light-emitting quantum dots with a quantum yield of unity. We found that hydrofluoric acid and zinc chloride additives are effective at enhancing luminescence efficiency by eliminating stacking faults in the ZnSe crystalline structure. In addition, chloride passivation through liquid or solid ligand exchange leads to slow radiative recombination, high thermal stability and efficient charge-transport properties. We constructed double quantum dot emitting layers with gradient chloride content in a light-emitting diode to facilitate hole transport, and the resulting device showed an efficiency at the theoretical limit, high brightness and long operational lifetime. We anticipate that our efficient and stable blue quantum dot light-emitting devices can facilitate the development of electroluminescent full-colour displays using quantum dots.
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The glycerol oxidation reaction (GOR) run with photoelectrochemical cells (PECs) is one of the most promising ways to upgrade biomass because it is thermodynamically favorable, while irreversible overoxidation leads to unsatisfactory product selectivities. Herein, a tunable one-dimensional nanoconfined environment was introduced into the GOR process, which accelerated mass transfer of glycerol via the microscale fluid effect and changed the main oxidation product from formic acid (FA) to glyceraldehyde (GLD), which led to retention of the heavier multicarbon products. The rate of glycerol diffusion in the nanochannels increased by a factor of 4.92 with decreasing inner diameters. The main product from the PEC-selective oxidation of glycerol changed from the C1 product FA to the C3 product GLD with a great selectivity of 60.7%. This work provides a favorable approach for inhibiting further oxidation of multicarbon products and illustrates the importance of microenvironmental regulation in biomass oxidation.
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Quantum dot (QD) light-emitting diodes (QLEDs) are promising for next-generation displays, but suffer from carrier imbalance arising from lower hole injection compared to electron injection. A defect engineering strategy is reported to tackle transport limitations in nickel oxide-based inorganic hole-injection layers (HILs) and find that hole injection is able to enhance in high-performance InP QLEDs using the newly designed material. Through optoelectronic simulations, how the electronic properties of NiOx affect hole injection efficiency into an InP QD layer, finding that efficient hole injection depends on lowering the hole injection barrier and enhancing the acceptor density of NiOx is explored. Li doping and oxygen enriching are identified as effective strategies to control intrinsic and extrinsic defects in NiOx, thereby increasing acceptor density, as evidenced by density functional theory calculations and experimental validation. With fine-tuned inorganic HIL, InP QLEDs exhibit a luminance of 45 200 cd m-2 and an external quantum efficiency of 19.9%, surpassing previous inorganic HIL-based QLEDs. This study provides a path to designing inorganic materials for more efficient and sustainable lighting and display technologies.
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Lithium-oxygen batteries have the potential to become the most eminent solution for future energy storage with their theoretical energy density exceeding all existing batteries. However, the insulating and insoluble discharge product (lithium peroxide; Li2O2) impairs practical application. Conventional catalyst designs based on the electronic structure and interfacial charge transfer descriptors have not been able to overcome these limitations due to Li2O2. Herein, we revisit the role of heterogeneous catalysts as substrates to regulate Li2O2 growth and the formation of solid/solid reaction interfaces. We demonstrate that controlled solid/solid interfacial structure design is a critical performance parameter beyond the inherent electronic structure. In particular, the Cu2O substrate in this study induces a homogeneous deposition of Pd atoms, which leads to well-controlled growth of Li2O2 resolving mass and charge transport limits (i.e., the bottleneck of oxygen reduction/evolution reactions), thus improving reversibility, capacity, and durability of the cells by dissipating electrochemical and mechanical stress. We thus verified the essential role of solid/solid interfaces to regulate the nucleation and growth process of Li2O2 in lithium-oxygen batteries.
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Indium phosphide (InP) quantum dots have enabled light-emitting diodes (LEDs) that are heavy-metal-free, narrow in emission linewidth, and physically flexible. However, ZnO/ZnMgO, the electron-transporting layer (ETL) in high-performance red InP/ZnSe/ZnS LEDs, suffers from high defect densities, quenches luminescence when deposited on InP, and induces performance degradation that arises due to trap migration from the ETL to the InP emitting layer. We posited that the formation of Zn2+ traps on the outer ZnS shell, combined with sulfur and oxygen vacancy migration between ZnO/ZnMgO and InP, may account for this issue. We synthesized therefore a bifunctional ETL (CNT2T, 3',3'â³,3'â³â³-(1,3,5-triazine-2,4,6-triyl)tris(([1,1'-biphenyl]-3-carbonitrile)) designed to passivate Zn2+ traps locally and in situ and to prevent vacancy migration between layers: the backbone of the small molecule ETL contains a triazine electron-withdrawing unit to ensure sufficient electron mobility (6 × 10-4 cm2 V-1 s-1), and the star-shaped structure with multiple cyano groups provides effective passivation of the ZnS surface. We report as a result red InP LEDs having an EQE of 15% and a luminance of over 12,000 cd m-2; this represents a record among organic-ETL-based red InP LEDs.
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Medical X-ray imaging procedures require digital flat detectors operating at low doses to reduce radiation health risks. Solution-processed organic-inorganic hybrid perovskites have characteristics that make them good candidates for the photoconductive layer of such sensitive detectors. However, such detectors have not yet been built on thin-film transistor arrays because it has been difficult to prepare thick perovskite films (more than a few hundred micrometres) over large areas (a detector is typically 50 centimetres by 50 centimetres). We report here an all-solution-based (in contrast to conventional vacuum processing) synthetic route to producing printable polycrystalline perovskites with sharply faceted large grains having morphologies and optoelectronic properties comparable to those of single crystals. High sensitivities of up to 11 microcoulombs per air KERMA of milligray per square centimetre (µC mGyair-1 cm-2) are achieved under irradiation with a 100-kilovolt bremsstrahlung source, which are at least one order of magnitude higher than the sensitivities achieved with currently used amorphous selenium or thallium-doped cesium iodide detectors. We demonstrate X-ray imaging in a conventional thin-film transistor substrate by embedding an 830-micrometre-thick perovskite film and an additional two interlayers of polymer/perovskite composites to provide conformal interfaces between perovskite films and electrodes that control dark currents and temporal charge carrier transportation. Such an all-solution-based perovskite detector could enable low-dose X-ray imaging, and could also be used in photoconductive devices for radiation imaging, sensing and energy harvesting.
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Compuestos de Calcio/química , Óxidos/química , Impresión , Dosis de Radiación , Radiografía/instrumentación , Radiografía/métodos , Titanio/química , Rayos X , Cesio/química , Electrodos , Diseño de Equipo , Yoduros/química , Fantasmas de Imagen , Selenio/química , Talio/química , Transistores ElectrónicosRESUMEN
Objective: While a rushed operation can omit essential procedures, prolonged operative time results in higher morbidity. Nevertheless, the optimal operative time range remains uncertain. This study aimed to estimate the ideal operative time range and evaluate its applicability in laparoscopic cancer surgery. Methods: A prospectively collected multicenter database of 397 patients who underwent laparoscopic distal gastrectomy were retrospectively reviewed. The ideal operative time range was statistically calculated by separately analyzing the operative time of uneventful surgeries. Finally, intraoperative and postoperative outcomes were compared among the shorter, ideal, and longer operative time groups. Results: The statistically calculated ideal operative time was 135.4-165.4 min. The longer operative time (LOT) group had a lower rate of uneventful, perfect surgery than the ideal or shorter operative time (IOT/SOT) group (2.8% vs. 8.8% and 2.2% vs. 13.4%, all P<0.05). Longer operative time increased bleeding, postoperative morbidities, and delayed diet and discharge (all P<0.05). Particularly, an uneventful, perfect surgery could not be achieved when the operative time exceeded 240 min. Regardless of ideal time range, SOT group achieved the highest percentage of uneventful surgery (13.4%), which was possible by surgeon's ability to retrieve a higher number of lymph nodes and perform ≥150 gastrectomies annually. Conclusions: Operative time longer than the ideal time range (especially ≥240 min) should be avoided. If the essential operative procedure were faithfully conducted without compromising oncological safety, an operative time shorter than the ideal range leaded to a better prognosis. Efforts to minimize operative time should be attempted with sufficient surgical experience.
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InP-based quantum dot (QD) light-emitting diodes (QLEDs) provide a heavy-metal-free route to size-tuned LEDs having high efficiency. The stability of QLEDs may be enhanced by replacing organic hole-injection layers (HILs) with inorganic layers. However, inorganic HILs reported to date suffer from inefficient hole injection, the result of their shallow work functions. Here, we investigate the tuning of the work function of nickel oxide (NiOx) HILs using self-assembled molecules (SAMs). Density functional theory simulations and near-edge X-ray absorption fine structure put a particular focus onto the molecular orientation of the SAMs in tuning the work function of the NiOx HIL. We find that orientation plays an even stronger role than does the underlying molecular dipole itself: SAMs having the strongest electron-withdrawing nitro group (NO2), despite having a high intrinsic dipole, show limited work function tuning, something we assign to their orientation parallel to the NiOx surface. We further find that the NO2 groupâwhich delocalizes electrons over the molecule by resonanceâinduces a deep lowest unoccupied molecular orbital level that accepts electrons from QDs, producing luminescence quenching. In contrast, SAMs containing a trifluoromethyl group exhibit an angled orientation relative to the NiOx surface, better activating hole injection into the active layer without inducing luminescence quenching. We report an external quantum efficiency (EQE) of 18.8%âthe highest EQE among inorganic HIL-based QLEDs (including Cd-based QDs)âin InP QLEDs employing inorganic HILs.
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In heterogeneous catalysts, metal-oxide interactions occur spontaneously but often in an undesired way leading to the oxidation of metal nanoparticles. Manipulating such interactions to produce highly active surface of metal nanoparticles can warrant the optimal catalytic activity but has not been established to date. Here we report that a prior reduced TiO2 support can reverse the interaction with Pt nanoparticles and augment the metallic state of Pt, exhibiting a 3-fold increase in hydrogen production rate compared to that of conventional Pt/TiO2. Spatially resolved electron energy loss spectroscopy of the Ti valence state and the electron density distribution within Pt nanoparticles provide direct evidence supporting that the Pt/TiO2/H2O triple junctions are the most active catalytic sites for water reduction. Our reverse metal-oxide interaction scheme provides a breakthrough in the stagnated hydrogen production efficiency and can be applied to other heterogeneous catalyst systems composed of metal nanoparticles with reducible oxide supports.
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Nanopartículas del Metal , Agua , Catálisis , Óxidos , TitanioRESUMEN
BACKGROUND: Greater lymph node retrieval in gastric cancer improves staging accuracy and may improve survival from increased clearance of nodal micrometastasis. This retrospective cohort study investigated if more lymph nodes removed in gastric cancer increases survival and if such effect is stage-specific due to differential risks of nodal micrometastasis and systemic disease. METHODS: The prospectively collected database of curatively resected gastric cancer patients in National Cancer Center, South Korea between 2000 and 2009 was reviewed. Disease-free survival (DFS) and overall survival (OS) for all patients and for each stage according to number of lymph nodes examined (1-30, 31-45, > 45) were analyzed. RESULTS: Of 4049 patients, 96.6% and 98.4% underwent D2 (perigastric and extragastric) lymphadenectomy and had ≥ 15 lymph nodes examined. Mean number of nodes examined was 43. Five-year OS & DFS rates were 83.3% and 80.7%. Patients with > 45 nodes examined had significantly lower DFS (p = 0.002) and OS (p = 0.007) compared to those with 1-30 and 31-45 nodes. However, proportion of patients with > 45 nodes examined increased with stage (p = 0.0005). Per stage, there was no significant difference in DFS and OS according to number of nodes examined except for stage IIIA favoring more nodes (p = 0.018 and p = 0.044, respectively). Similar trend was seen in stage IIB. Number of examined nodes positively correlated with number of pathologic nodes for all patients (r = 0.144, p < .001) but not for stage IIB and IIIA. Number of nodes examined was a significant survival predictor in stage IIIA. CONCLUSION: Greater lymph node harvest showed improved survival in intermediate-stage gastric cancer.
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Adenocarcinoma/epidemiología , Adenocarcinoma/cirugía , Neoplasias Gástricas/epidemiología , Neoplasias Gástricas/cirugía , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/patología , Adulto , Anciano , Supervivencia sin Enfermedad , Femenino , Gastrectomía , Humanos , Estimación de Kaplan-Meier , Escisión del Ganglio Linfático , Ganglios Linfáticos/patología , Ganglios Linfáticos/cirugía , Metástasis Linfática , Masculino , Persona de Mediana Edad , Micrometástasis de Neoplasia , Pronóstico , República de Corea/epidemiología , Estudios Retrospectivos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/patologíaRESUMEN
BACKGROUND AND AIMS: Excellent long-term outcome is expected for early gastric cancers (EGCs) after endoscopic submucosal dissection (ESD). However, if ESD is considered noncurative at the pathologic evaluation, additional surgery is recommended. We evaluated whether long-term outcome is compromised if additional surgery is not performed for EGCs that are out-of-indication. METHODS: We retrospectively analyzed a cohort of patients with EGC not meeting ESD indications whose initial treatment was either ESD (n = 219) or surgery (n = 1799). Among them, 127 patients who underwent additional surgery after initial ESD and 67 patients who did not were matched using propensity scores to patients who initially underwent standard surgery, at a 1:1 ratio. Overall mortality and gastric cancer recurrence were compared. RESULTS: The overall mortality and gastric cancer recurrence rates were not significantly different between the 127 patients who underwent initial ESD with additional surgery and the corresponding initial standard surgery patients. However, the overall mortality of the 67 patients who underwent ESD without additional surgery (5-year mortality, 26.0%; 95% CI, 13.5%-49.9%) was higher than that of the matched initial standard surgery patients (5-year mortality, 14.5%; 95% CI, 6.3%-33.6%; P = .04). Gastric cancer recurrence was also higher in ESD patients without additional surgery (5-year recurrence, 17.0%; 95% CI, 7.6%-37.8%) than in the matched initial surgery group (0%; P = .002). In multivariate analyses, ESD without additional surgery was a significant risk factor for overall mortality and gastric cancer recurrence. CONCLUSIONS: Additional surgery should be encouraged after non-curative ESD to obtain long-term outcomes comparable with those of initial standard surgery. (Clinical trial registration number: NCC2015-0093.).
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Adenocarcinoma/mortalidad , Adenocarcinoma/cirugía , Resección Endoscópica de la Mucosa , Gastrectomía , Escisión del Ganglio Linfático , Recurrencia Local de Neoplasia/epidemiología , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/cirugía , Adenocarcinoma/patología , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Puntaje de Propensión , Reoperación , Estudios Retrospectivos , Neoplasias Gástricas/patología , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
A vertically integrated junctionless field-effect transistor (VJ-FET), which is composed of vertically stacked multiple silicon nanowires (SiNWs) with a gate-all-around (GAA) structure, is demonstrated on a bulk silicon wafer for the first time. The proposed VJ-FET mitigates the issues of variability and fabrication complexity that are encountered in the vertically integrated multi-NW FET (VM-FET) based on an identical structure in which the VM-FET, as recently reported, harnesses a source and drain (S/D) junction for its operation and is thus based on the inversion mode. Variability is alleviated by bulk conduction in a junctionless FET (JL-FET), where current flows through the core of the SiNW, whereas it is not mitigated by surface conduction in an inversion mode FET (IM-FET), where current flows via the surface of the SiNW. The fabrication complexity is reduced by the inherent JL structure of the JL-FET because S/D formation is not required. In contrast, it is very difficult to dope the S/D when it is positioned at each floor of a tall SiNW with greater uniformity and with less damage to the crystalline structure of the SiNW in a VM-FET. Moreover, when the proposed VJ-FET is used as nonvolatile flash memory, the endurance and retention characteristics are improved due to the above-mentioned bulk conduction.
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BACKGROUND AND AIM: The aim of this study was to evaluate the validity of the parameters of conventional white-light endoscopy and magnifying endoscopy with narrow-band imaging (MENBI) for the prediction of discrepancies between pre- and post-resectional histology in cases of gastric adenoma with low-grade dysplasia (LGD) that were diagnosed based on endoscopically biopsied specimens. METHODS: The medical records of 266 lesions with gastric LGD that were diagnosed by endoscopic forceps biopsies were retrospectively reviewed. The Vienna classification was used for histologic diagnosis. These patients all underwent MENBI examinations followed by analyses of the incidence of histologic discrepancies and histologic heterogeneity. The relationship between white-light endoscopic/MENBI parameters and the presence of histologic discrepancies was also analyzed. RESULTS: Discrepancies between the pre- and post-resectional histologies were found in 74 cases (27.9%). Among those cases, the histology was upgraded in 71 cases, whereas the histology was downgraded in three cases. The presence of erythema and positive MENBI findings were independent factors for the prediction of upgraded histologic discrepancies (P-values = 0.008, < 0.001, respectively). A positive MENBI finding yielded the highest predictive value, with a multivariate adjusted odds ratio of 42.46. Histologic heterogeneity in post-resectional specimens was found in 40.8% of cases with upgraded histologic discrepancies. CONCLUSIONS: MENBI can provide more accurate information than white-light endoscopy for the prediction of pre- and post-resectional histologic discrepancies in biopsy-proven gastric LGD. Endoscopic resection is strongly recommended in cases with surface erythema on conventional white-light endoscopy or positive MENBI, irrespective of the lesion size.
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Adenoma/patología , Biopsia/métodos , Endoscopía Gastrointestinal/métodos , Mucosa Gástrica/patología , Neoplasias Gástricas/patología , Adenoma/diagnóstico , Anciano , Biopsia/instrumentación , Endoscopía Gastrointestinal/instrumentación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Sensibilidad y Especificidad , Neoplasias Gástricas/diagnóstico , Instrumentos QuirúrgicosRESUMEN
1. Fimasartan is an angiotensin receptor II antagonist used to treat patients with hypertension. This drug is mainly excreted into bile as either the parent compound or a glucuronide conjugate. In this study, we examined the glucuronidation of fimasartan and characterized the UDP-glucuronosyltransferases (UGTs) responsible for the glucuronidation. 2. Only one type of fimasartan glucuronide was observed after incubation with pooled human liver microsomes (HLMs) and was identified as an N2-glucuronide based on comparison with an authentic standard. 3. Among the 12 UGT isoforms tested, UGT1A1, UGT1A3 and UGT2B7 showed catalytic activity toward fimasartan glucuronidation. The intrinsic clearance (CLint) of UGT1A3 was 68.5- and 21.4-fold higher than that of UGT1A1 and UGT2B7, respectively, and the estimated relative contribution of UGT1A3 in human liver was 94.1%. Both chemical inhibition and correlation studies demonstrated that fimasartan glucuronidation activity in HLMs was significantly related with UGT1A3 activity. Fimasartan glucuronide was identified as a substrate for P-glycoprotein (Pgp) and breast cancer response protein (BCRP). 4. These findings collectively indicate that UGT1A3 is the major UGT isoform responsible for the glucuronidation of fimasartan, and this glucuronide is excreted from hepatocytes via MDR1 and BCRP.
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Antagonistas de Receptores de Angiotensina/metabolismo , Compuestos de Bifenilo/metabolismo , Glucuronosiltransferasa/metabolismo , Microsomas Hepáticos/enzimología , Pirimidinas/metabolismo , Tetrazoles/metabolismo , Glucuronosiltransferasa/antagonistas & inhibidores , Humanos , Isoenzimas/metabolismo , CinéticaRESUMEN
BACKGROUND: FOLFOX-based adjuvant chemotherapy is a benefit for high-risk stage II and stage III colon cancer after curative resection. But, the prognostic factor or predictive marker for the efficacy of FOLFOX remains unclear. This study was aimed to identify the prognostic value and cumulative impact of adjuvant FOLFOX on the stage II and III colon cancer patients. METHODS: A total of 196 stage II and III colon cancer patients were retrospectively enrolled in prospectively collected data. They underwent curative resection followed by FOLFOX4 adjuvant chemotherapy. The oncological outcomes included the 5-year disease-free survival (DFS) rate and 5-year overall survival (OS) rate. Cox-regression analysis was performed to identify the prognostic value, and its cumulative impact was analyzed. RESULTS: The 5-year DFS rate of the patients was 71.94% and the 5-year OS rate was 81.5%. The prognostic values for the 5-year DFS rate and 5-year OS rate were T4 stage and preoperative anemia in a multivariate analysis. Each patient group who had no prognostic value, single, or both factors revealed 95.35%, 69.06%, and 28.57% in the 5-year DFS rate, respectively (p < 0.0001). The 5-year OS rate also showed the significant differences in each group who had no prognostic value, single, or both factors revealed 100%, 79.3%, and 45.92%, respectively (p < 0.0001). CONCLUSION: Our results showed similar efficacy to MOSAIC study in stage II and stage III colon cancer patients treated with adjuvant FOLFOX chemotherapy after curative resection. Patients who had T4 stage and/or preoperative anemia showed worse prognosis than patients without any prognostic value. These findings suggest that FOLFOX could not be effective in the patients with T4 stage colon cancer accompanied by preoperative anemia.
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Anemia/fisiopatología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/mortalidad , Adenocarcinoma Mucinoso/tratamiento farmacológico , Adenocarcinoma Mucinoso/mortalidad , Adenocarcinoma Mucinoso/patología , Adulto , Anciano , Carcinoma de Células en Anillo de Sello/tratamiento farmacológico , Carcinoma de Células en Anillo de Sello/mortalidad , Carcinoma de Células en Anillo de Sello/patología , Neoplasias del Colon/patología , Femenino , Fluorouracilo/uso terapéutico , Estudios de Seguimiento , Humanos , Leucovorina/uso terapéutico , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Compuestos Organoplatinos/uso terapéutico , Cuidados Preoperatorios , Pronóstico , Estudios Prospectivos , Estudios Retrospectivos , Tasa de SupervivenciaRESUMEN
A carbon capture and use (CCU) strategy was applied to organic synthesis. Carbon dioxide (CO2) captured directly from exhaust gas was used for organic transformations as efficiently as hyper-pure CO2 gas from a commercial source, even for highly air- and moisture-sensitive reactions. The CO2 capturing aqueous ethanolamine solution could be recycled continuously without any diminished reaction efficiency.
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Anode-free (or lithium-metal-free) batteries with garnet-type solid-state electrolytes are considered a promising path in the development of safe and high-energy-density batteries. However, their practical implementation has been hindered by the internal strain that arises from the repeated plating and stripping of lithium metal at the interlayer between the solid electrolyte and negative electrode. Herein, we utilize the titanium nitrate nanotube architecture and a silver-carbon interlayer to mitigate the anisotropic stress caused by the recurring formation of lithium deposition layers during the cycling process. The mixed ionic-electronic conducting nature of the titanium nitrate nanotubes effectively accommodates the entry of reduced Li into its free volume space via interfacial diffusion creep, achieving near-strain-free operation with nearly tenfold volume suppressing capability compared to a conventional Cu anode counterpart during the lithiation process. Notably, the fabricated Li6.4La3Zr1.7Ta0.3O12 (LLZTO)-based initial-anode-free quasi-solid-state battery full cell, coupled with an ionic liquid catholyte infused high voltage LiNi0.33Co0.33Mn0.33O2-based cathode with an areal capacity of 3.2 mA cm-2, exhibits remarkable room temperature (25 °C) cyclability of over 600 cycles at 1 mA cm-2 with an average coulombic efficiency of 99.8%.
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INTRODUCTION: Colon cancer obstruction is one of the most serious conditions in colorectal surgery. However, the use of self-expanding metallic stent (SEMS) has made it possible to avoid emergency surgery and stoma creation, therefore enabling minimally invasive surgery and one-stage operation. In this study, we aimed to investigate whether there is an optimal interval from SEMS to surgery for the best long-term oncologic outcomes. METHODS: Obstructive colon cancer patients treated with SEMS insertion and received surgery were included in the study. Patient data were retrospectively reviewed in prospectively collected data. Using the ROC curve, the optimal interval to surgery after SEMS insertion was 10 days; the patients were divided into the early surgery group (≤10 days, ES) and the late surgery group (>10 days, LS). Factors contributing to the 5-year disease-free survival (DFS) and overall survival (OS) were analyzed. RESULTS: 83 patients were included in this study. Eight patients (9.6 %) had SEMS insertion failure, with 3 perforations and 5 failed expansions. There were no differences between the ES group and the LS group in terms of pathologic characteristics, incidence of stoma creation, and adjuvant chemotherapy. Twenty-six patients (31.3 %) had recurrences; local (Arnarson et al., 2023) [6], peritoneal seeding (Lee et al., 2013) [8], liver (Ho et al., 2017) [11], lung [7], bone (van Hooft et al., 2020) [2], and abdominal wall metastasis (Chen and Sheen-Chen, 2000) [1]. The 5-year DFS rate was significantly better in the ES group than the LS group (74.3 % vs. 55.01 %; p = 0.0394). The 5-year OS was slightly better in the ES group than the LS group (76.11 % vs. 58.75 %; p = 0.0901). In univariable analysis, the ES group showed a lower risk of recurrence than the LS group (OR: 0.447 [0.204-0.984], p = 0.0455), but this was not reproduced in the multivariable analysis. CONCLUSION: This study has shown that the long-term oncologic outcomes were better in patients who received surgery after SEMS within 10 days. Hence, we propose with caution that elective surgery might be suggested to take place within 10 days from SEMS insertion for better oncologic outcomes.
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BACKGROUNDS: Strong evidence is lacking as no confirmatory randomized controlled trials (RCTs) have compared the efficacy of totally laparoscopic distal gastrectomy (TLDG) with laparoscopy-assisted distal gastrectomy (LADG). The authors performed an RCT to confirm if TLDG is different from LADG. METHODS: The KLASS-07 trial is a multi-centre, open-label, parallel-group, phase III, RCT of 442 patients with clinical stage I gastric cancer. Patients were enroled from 21 cancer care centres in South Korea between January 2018 and September 2020 and randomized to undergo TLDG or LADG using blocked randomization with a 1:1 allocation ratio, stratified by the participating investigators. Patients were treated through R0 resections by TLDG or LADG as the full analysis set of the KLASS-07 trial. The primary endpoint was morbidity within postoperative day 30, and the secondary endpoint was quality of life (QoL) for 1 year. This trial is registered at ClinicalTrials.gov (NCT03393182). RESULTS: Four hundred forty-two patients were randomized (222 to TLDG, 220 to LADG), and 422 patients were included in the pure analysis (213 and 209, respectively). The overall complication rate did not differ between the two groups (TLDG vs. LADG: 12.2% vs. 17.2%). However, TLDG provided less postoperative ileus and pulmonary complications than LADG (0.9% vs. 5.7%, P= 0.006; and 0.5% vs. 4.3%, P= 0.035, respectively). The QoL was better after TLDG than after LADG regarding emotional functioning at 6 months, pain at 3 months, anxiety at 3 and 6 months, and body image at 3 and 6 months (all P< 0.05). However, these QoL differences were resolved at 1 year. CONCLUSIONS: The KLASS-07 trial confirmed that TLDG is not different from LADG in terms of postoperative complications but has the advantages to reduce ileus and pulmonary complications. TLDG can be a good option to offer better QoL in terms of pain, body image, emotion, and anxiety at 3-6 months.
JOURNAL/ijos/04.03/01279778-202408000-00031/figure1/v/2024-08-13T152924Z/r/image-jpeg.
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Gastrectomía , Laparoscopía , Complicaciones Posoperatorias , Calidad de Vida , Neoplasias Gástricas , Humanos , Gastrectomía/métodos , Gastrectomía/efectos adversos , Laparoscopía/métodos , Laparoscopía/efectos adversos , Masculino , Femenino , Neoplasias Gástricas/cirugía , Persona de Mediana Edad , Anciano , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , República de Corea , Resultado del Tratamiento , AdultoRESUMEN
BACKGROUND: Petersen's hernia, which occurs after Billroth-II (B-II) or Roux-en-Y (REY) anastomosis, can be reduced by defect closure. This study aims to compare the incidence of bowel obstruction above Clavien-Dindo classification grade III due to Petersen's hernia between the mesenteric fixation method and the conventional methods after laparoscopic or robotic gastrectomy. METHODS: This study was designed as prospective, single-blind, non-inferiority randomized controlled multicenter trial in Korea. Patients with histologically diagnosed gastric cancer of clinical stages I, II, or III who underwent B-II or REY anastomosis after laparoscopic or robotic gastrectomy are enrolled in this study. Participants who meet the inclusion criteria are randomly assigned to two groups: a CLOSURE group that underwent conventional Petersen's defect closure method and a MEFIX group that underwent the mesenteric fixation method. The primary endpoint is the number of patients who underwent surgery for bowel obstruction caused by Petersen's hernia within 3 years after laparoscopic or robotic gastrectomy. DISCUSSION: This trial is expected to provide high-level evidence showing that the MEFIX method can quickly and easily close Petersen's defect without increased postoperative complications compared to the conventional method. TRIAL REGISTRATION: ClinicalTrials.gov NCT05105360. Registered on November 3, 2021.