High Proton Conduction in the Octahedral Layers of Fully Hydrated Hexagonal Perovskite-Related Oxides.

Proton conductors have potential applications such as fuel cells, electrolysis cells, and sensors. These applications require new materials with high proton conductivity and high chemical stability at intermediate temperatures. Herein we report a series of new hexagonal perovskite-related oxides, Ba5R2Al2SnO13 (R = Gd, Dy, Ho, Y, Er, Tm, and Yb). Ba5Er2Al2SnO13 exhibited a high proton conductivity without chemical doping (e.g., 0.01 S cm-1 at 303 °C), which is attributed to its high proton concentration and diffusion coefficient. The high diffusion coefficient of Ba5Er2Al2SnO13 can be attributed to the fast proton migration in the octahedral layers. The high proton concentration is attributed to full hydration in hydrated Ba5Er2Al2SnO13 and the large amount of intrinsic oxygen vacancies in the dry sample, as evidenced by both neutron diffraction and thermogravimetric analysis. Ba5Er2Al2SnO13 was found to exhibit high chemical stability under wet atmospheres of O2, air, H2, and CO2. High proton conductivity and high chemical stability indicate that Ba5Er2Al2SnO13 is a superior proton conductor. Ba5R2Al2SnO13 (R = Gd, Dy, Ho, Y, Tm, and Yb) exhibited high electrical conductivity in wet N2, suggesting that these materials also exhibit high proton conductivity. These findings will open new avenues for proton conductors. The high proton conductivity via full hydration and fast proton migration in octahedral layers in highly oxygen-deficient hexagonal perovskite-related materials would be an effective strategy for developing next-generation proton conductors.

Combination of crystal growth with optical floating zone and evaluation of Nd3+:LaAlO3 crystals with the dynamic nuclear polarization of 139La and 27Al.

Producing a polarized lanthanum (La) target with high polarization and long relaxation time is crucial for realizing time-reversal violation experiments using polarized neutron beams. We use a LaAlO3 crystal doped with a small amount of Nd3+ ions for the polarized lanthanum target. Optimizing the amount of Nd3+ ions is considerably important because the achievable polarization and relaxation time strongly depend on this amount. We established a fundamental method to grow single crystals of Nd3+:LaAlO3 using an optical floating zone method that employs halogen lamps and evaluated the crystals with the dynamic nuclear polarization (DNP) method for polarizing nuclear spins. Two crystal samples were grown by ourselves and evaluated with the DNP at 1.3 K and 2.3 T for the first time, except for the target materials of protons. The enhancement of nuclear magnetic resonance signals for 139La and 27Al was successfully observed, and the enhancement factors were eventually 3.5 ± 0.3 and 13 ± 3 for the samples with Nd3+ ions of 0.05 and 0.01 mol. %, respectively. These enhancement factors correspond to absolute vector polarizations of 0.27% ± 0.02% (Nd3+ 0.05 mol. %) and 1.4% ± 0.3% (Nd3+ 0.01 mol. %). Although the obtained polarizations are still low, they are acceptable as a first step. The combination scheme of the crystal growth and the evaluation of the crystals is found to be effectively applicable for optimizing the amount of Nd3+ ions for improving the performance of the polarized target.

Preoperative Hemoglobin Level as Predictor of the Development of High-output Stoma in Rectal Cancer Surgery.

Background/Aim: High-output stomas (HOSs) are a complication that can cause dehydration or renal dysfunction and affect the quality of life of patients, causing water, sodium, and magnesium depletion with malnutrition. Preoperative factors that are useful for predicting HOS are not well defined. Patients and Methods: A total of nine patients developed HOS among 31 patients who underwent rectal cancer surgery with ileostomies during 2014-2021. Clinicopathological and surgical parameters were also analyzed. HOS was defined as maximum output of ≥2,000 ml/day. Results: The clinicopathological features did not differ between the HOS and non-HOS groups. Lower Hemoglobin (Hb) levels (<12 mg/dl) and longer operation times (≥300 min) were shown to be risk factors in the development of HOS. Conclusion: Low Hb levels on preoperative blood tests were predictors of HOS development in patients who underwent rectal cancer surgery and ileostomies simultaneously in our data set. Further studies are required to improve the robustness of these findings.

Doubly Charmed Tetraquark T_{cc}

The doubly charmed tetraquark T_{cc}^{+} recently discovered by the LHCb Collaboration is studied on the basis of (2+1)-flavor lattice QCD simulations of the D^{*}D system with nearly physical pion mass m_{π}=146 MeV. The interaction of D^{*}D in the isoscalar and S-wave channel, derived from the hadronic spacetime correlation by the HAL QCD method, is attractive for all distances and leads to a near-threshold virtual state with a pole position E_{pole}=-59(_{-99}^{+53})(_{-67}^{+2}) keV and a large scattering length 1/a_{0}=0.05(5)(_{-2}^{+2}) fm^{-1}. The virtual state is shown to evolve into a loosely bound state as m_{π} decreases to its physical value by using a potential modified to m_{π}=135 MeV based on the pion-exchange interaction. Such a potential is found to give a semiquantitative description of the LHCb data on the D^{0}D^{0}π^{+} mass spectrum. Future study is necessary to perform physical-point simulations with the isospin-breaking and open three-body-channel effects taken into account.

Successful Treatment of Refractory Enterocutaneous Fistula After Esophagectomy Using Soft Coagulation by an Endoscopic and Percutaneous Approach: A Case Report.

BACKGROUND/AIM: Anastomotic leakage (AL) is a serious complication after esophagectomy, and the refractory fistula (RF) following AL is therapeutically challenging with no optimal management strategies known. Thus, new therapeutic options are required for treating RF. CASE REPORT: A 67-year-old man who underwent endoscopic mucosal dissection was subjected to subtotal esophagectomy and reconstruction with a gastric tube through the retrosternal route with cervical anastomosis as additional therapy. On postoperative day 5, leakage from the esophagogastric anastomosis was detected. A refractory enterocutaneous fistula (4 cm in length) developed between the esophagogastric anastomosis (the fistula opening was 1 cm approximately) and cervical skin. The RF did not heal despite the drainage of saliva, enteral nutrition, oral administration of biperiden hydrochloride for orofacial dyskinesia to rest the esophagogastric anastomosis, coagulation factor XIII transvenously, and fibrin glue injection from the opening of the fistula, probably due to difficulty in maintaining the rest of the esophagogastric anastomosis caused by orofacial dyskinesia. On postoperative day 76, soft coagulation to the fistula opening at the esophagogastric anastomosis by an endoscopic approach and to the fistula via the fistula opening at the cervical site by a percutaneous approach was performed. The post-treatment course was uneventful. The RF completely closed immediately after soft coagulation. CONCLUSION: Soft coagulation using endoscopic and percutaneous approaches to RF is a minimally invasive procedure and may be a useful option if the fistula opening of the anastomotic site is small and accessible endoscopically, and there are no vital organs around the fistula.

Survival Benefits of Laparoscopic Gastrectomy in Elderly Patients With Gastric Cancer: Focusing on Preoperative Nutritional and Inflammatory Status.

BACKGROUND/AIM: Laparoscopic gastrectomy (LG) may have greater clinical benefits as a less invasive surgery for elderly patients with gastric cancer (GC). Therefore, we aimed to evaluate the survival benefit of LG in elderly patients with GC, especially focusing on preoperative comorbidities, and nutritional and inflammatory status. PATIENTS AND METHODS: Data collected from 115 patients aged ≥75 years with primary GC who underwent curative gastrectomy, comprising 58 patients who underwent open gastrectomy (OG) and 57 patients who underwent LG, were retrospectively reviewed (total cohort), and 72 propensity-matched patients (matched cohort) were selected for survival analysis. The aim of the study was to determine short- and long-term outcomes, and the clinical markers to identify a population who may benefit from LG in elderly patients. RESULTS: The complication and mortality rates as a short-term outcome in the total cohort and overall survival (OS) as a long-term outcome in the matched cohort did not differ significantly between the groups. In the total cohort, advanced tumor stage and ≥3 comorbidities were independent factors for poor prognosis in terms of OS [hazard ratio (HR)=3.73, 95% confidence interval (CI)=1.78-7.78, p<0.001 and HR=2.50, 95% CI=1.35-4.61, p<0.01, respectively]. The surgical approach was not an independent risk factor for postoperative complications (grade ≥III) and OS. In subgroup analysis of the total cohort, patients with a neutrophil-lymphocyte ratio (NLR) ≥3 in the LG group demonstrated a trend toward greater OS (HR=0.26, 95% CI=0.10-0.64, interaction p<0.05). CONCLUSION: LG might offer greater survival benefits than OG in frail patients such as those with high NLR.

Successful conversion surgery following chemotherapy with an immune checkpoint inhibitor in an older adult patient with stage IVB esophageal squamous cell carcinoma: a case report.

BACKGROUND: Chemotherapy and chemoradiotherapy are common treatments for esophageal squamous cell carcinoma with distant metastasis; however, the prognosis remains poor, and complete remission is difficult to achieve. Here, we report a case of an older adult patient with esophageal squamous cell carcinoma who underwent surgery following combined treatment of immunotherapy and chemotherapy and achieved pathological complete response. CASE PRESENTATION: An 80-year-old woman presenting with difficulty swallowing was referred to our hospital. She was diagnosed with esophageal squamous cell carcinoma with distant metastasis of the lymph node at the dorsal side of the IVC and the left supraclavicular lymph node. She was treated with pembrolizumab, cisplatin, and 5-fluorouracil. After four pharmacotherapy courses, primary tumor and metastatic lymph node shrinkage was observed. The patient underwent thoracoscopic subtotal esophagectomy and regional lymph node dissection. The lymph node at the dorsal side of the IVC was not resected, and the left supraclavicular lymph node was removed. Histological examination revealed complete response with no residual tumor or lymph node metastasis. The patient had no recurrence 10 months postoperatively without adjuvant chemotherapy. CONCLUSIONS: Conversion surgery following preoperative therapy, including immunotherapy, may be an effective treatment strategy for improving survival in patients with esophageal squamous cell carcinoma even among older adult patients.

Refractory splenic bleeding from splenic angiosarcoma: A case report and literature review.

INTRODUCTION AND IMPORTANCE: Atraumatic splenic rupture (ASR) is a rare state that accounts for only <1 % of splenic ruptures. One of the causes of ASR is splenic neoplasm such as angiosarcoma. The treatment strategy for ASR is still unclear given the small number of cases reported in detail. CASE PRESENTATION: A 75-year-old woman presenting with abdominal pain with shock was referred to our hospital. Emergency computed tomography revealed splenic rupture, and hemodynamic stabilization was obtained by emergent vascular embolization. Rebleeding occurred 27 days after the initial treatment, and splenectomy was performed. Pathologically, ASR was diagnosed as caused by splenic angiosarcoma. CLINICAL DISCUSSION: ASR is a very rare disease. The etiology of ASR has been reported as neoplastic, infectious, and so on. The treatment for ASR should be decided considering the etiology of ASR, hemodynamic stability, volume of blood transfusion, patient status, severity of the splenic injury, and volume of intraperitoneal bleeding. CONCLUSIONS: We experienced a very rare case of ASR, in which diagnosis was challenging and the timing of surgery was difficult to determine. When splenic rupture has an atraumatic cause, splenectomy should be considered because of the possibility of malignancy.

SrV0.3Fe0.7O2.8: A Vacancy-Ordered Fe-Based Perovskite Exhibiting Room-Temperature Magnetoresistance.

We report room-temperature (RT) magnetoresistance (MR) in a novel Fe-based perovskite, SrV0.3Fe0.7O2.8. This compound contains ordered oxygen vacancies in every fifth primitive perovskite (111)p plane, leading to a layered structure consisting of triple-octahedral and double-tetrahedral layers. Along with the oxygen vacancies, the transition-metal ions are also ordered: the octahedral sites are occupied by 100% of Fe ions, while the tetrahedral sites are occupied by 25% of Fe ions and 75% of V ions. As a result, SrV0.3Fe0.7O2.8 forms a magnetically striped lattice in which the octahedral layers with 100% of magnetic Fe ions are separated by the diluted magnetic layer. The compound exhibits weak ferromagnetism and shows a large negative MR (-5% at 3 T) at RT, despite the small saturation moment (0.4 µB/Fe atom). Thus, this type of layered compound is promising for further large MR by an increase of magnetization through chemical substitution.

A New Compartment Model of COVID-19 Transmission: The Broken-Link Model.

We propose a new compartment model of COVID-19 spread, the broken-link model, which includes the effect from unconnected infectious links of the transmission. The traditional SIR-type epidemic models are widely used to analyze the spread status, and the models show the exponential growth of the number of infected people. However, even in the early stage of the spread, it is proven by the actual data that the exponential growth did not occur all over the world. We presume this is caused by the suppression of secondary and higher-order transmissions of COVID-19. We find that the proposed broken-link model quantitatively describes the mechanism of this suppression, which leads to the shape of epicurves of confirmed cases are governed by the probability of unconnected infectious links, and the magnitudes of the cases are proportional to expR0 in each infectious surge generated by a virus of the basic reproduction number R0, and is consistent with the actual data.

Synthesis of Hydride-Doped Perovskite Stannate with Visible Light Absorption Capability.

Narrow-gap semiconductors with visible light absorption capability have attracted attention as photofunctional materials. H--doped BaSn0.7Y0.3O3-δ containing Sn(II) species was recently reported to absorb visible light up to 600 nm, which represents the first demonstration of oxyhydride-based visible-light-absorbers. In the present study, a more detailed investigation was made to obtain information on the synthesis and properties of H--doped perovskite-type stannate with respect to the A-site cation of the material and the preparation conditions. H--doped ASn0.7Y0.3O3-δ (A = Ba, Ba0.5Sr0.5, and Sr) obtained by the reaction of ASn0.7Y0.3O3-δ precursors with CaH2 at 773 K under vacuum conditions was shown to have almost the same bandgap (ca. 2.1 eV), regardless of the A-site cation. Physicochemical measurements and theoretical calculations revealed that the identical bandgaps of H--doped ASn0.7Y0.3O3-δ are due to the simultaneous shift of the midgap states composed of Sn2+ with the conduction band minimum. Experimental results also indicated that the appropriate preparation conditions with respect to Y3+-substitution and the temperature for the synthesis of the ASn0.7Y0.3O3-δ precursors were essential to obtain H--doped products that have a low density of defects.

Survival benefits of gastrectomy compared to conservative observation for older patients with resectable gastric cancer: a propensity score matched analysis.

PURPOSE: Radical gastrectomy is considered the first choice of curative treatment for older patients with gastric cancer (GC). However, there is limited data on the survival benefits of gastrectomy for older patients with GC. METHODS: This was a retrospective observational study where medical records of patients aged ≥ 75 years with clinically resectable primary GC, comprising 115 patients who underwent radical surgery (S group) and 33 patients who received conservative therapy (non-S group) (total cohort) and 44 propensity-matched patients (matched cohort), were reviewed. Survival and independent risk factors, including comorbidities and systemic nutritional and inflammatory statuses, were evaluated. RESULTS: In the total cohort, the 5-year overall survival (OS) in the S group was significantly higher than that in the non-S group (53.7% vs 19.7%, P < 0.0001). In the matched cohort, the 3-year OS in the S group was significantly higher than that in the non-S group (59.4% vs 15.9%, P < 0.01). Multivariate analysis of the total cohort showed that no surgery was an independent prognostic factor for poor OS (hazard ratio (HR) 3.70, 95% confidence interval (CI) 1.91-7.20, P = 0.0001). In the S group in the total cohort, the multivariate analysis showed that renal disease (HR 2.51, 95% CI 1.23-5.12, P < 0.05) was an independent prognostic factor for poor OS. CONCLUSIONS: Gastrectomy for older patients improved the prognosis; however, careful patient selection is essential, especially among those with renal disease.

Novel assays to monitor gene expression and protein-protein interactions in rice using the bioluminescent protein, NanoLuc.

Luciferases have been widely utilized as sensitive reporters to monitor gene expression and protein-protein interactions. Compared to firefly luciferase (Fluc), a recently developed luciferase, Nanoluciferase (NanoLuc or Nluc), has several superior properties such as a smaller size and stronger luminescence activity. We compared the reporter properties of Nluc and Fluc in rice (Oryza sativa). In both plant-based two-hybrid and split luc complementation (SLC) assays, Nluc activity was detected with higher sensitivity and specificity than that with Fluc. To apply Nluc to research involving the photoperiodic regulation of flowering, we made a knock-in rice plant in which the Nluc coding region was inserted in-frame with the OsMADS15 gene, a target of the rice florigen Hd3a. Strong Nluc activity in response to Hd3a, and in response to change in day length, was detected in rice protoplasts and in a single shoot apical meristem, respectively. Our results indicate that Nluc assay systems will be powerful tools to monitor gene expression and protein-protein interaction in plant research.

The influence of the interval between percutaneous transhepatic gallbladder drainage and cholecystectomy on perioperative outcomes: a retrospective study.

BACKGROUND: Percutaneous transhepatic gallbladder drainage (PTGBD) is recommended for acute cholecystitis patients at high risk for surgical treatment. However, there is no evidence about the best timing of surgery after PTGBD. Here, we retrospectively investigated the influence of the interval between PTGBD and surgery on perioperative outcomes and examined the optimal timing of surgery after PTGBD. METHODS: We performed a retrospective analysis of 22 patients who underwent cholecystectomy after PTGBD from January 2008 to August 2019. We examined perioperative factors between patients with an interval of ≤ 7 days between PTGBD and cholecystectomy (≤ 7-day group; n = 12) and those with an interval of ≥ 8 days (≥ 8-day group; n = 10). Moreover, we also examined perioperative factors between patients with an interval of ≤ 14 days from PTGBD to cholecystectomy (≤ 14-day group; n = 10) and those with an interval of ≥ 15 days (≥ 15-day group; n = 12). RESULTS: Of the 22 patients, 9 had Grade I cholecystitis, 12 had Grade II cholecystitis, and 2 had Grade III cholecystitis. Nine patients had high-grade cholecystitis before PTGBD and 13 had a poor general condition. We examined perioperative factors between patients with an interval of ≤ 7 days between PTGBD and cholecystectomy (≤ 7-day group; n = 12) and those with an interval of ≥ 8 days (≥ 8-day group; n = 10). The C-reactive protein (CRP) level before surgery was significantly higher (12.70 ± 1.95 mg/dL vs. 1.13 ± 2.13 mg/dL, p = 0.0007) and the total hospitalization was shorter (17.6 ± 8.0 days vs. 54.1 ± 8.8 days, p = 0.0060) in the ≤ 7-day group than in the ≥ 8-day group. We also examined perioperative factors between patients with an interval of ≤ 14 days from PTGBD to cholecystectomy (≤ 14-day group; n = 14) and those with an interval of ≥ 15 days (≥ 15-day group; n = 8). The CRP level before surgery was significantly higher (11.13 ± 2.00 mg/dL vs. 0.99 ± 2.64 mg/dL, p = 0.0062) and the total hospitalization was shorter (19.5 ± 7.2 days vs. 59.9 ± 9.5 days, p = 0.0029) in the ≤ 14-day group than in the ≥ 15-day group. However, there were no significant differences between the ≤ 14-day group and the ≥ 15-day group in the levels of hepatic enzymes before surgery, adhesion grade, amount of bleeding during surgery, operative duration, frequency of surgical complications, or length of hospitalization after surgery. CONCLUSIONS: The interval between PTGBD and surgery has little influence on perioperative outcomes.

Intra-abdominal Desmoid-Type Fibromatosis Mimicking Diverticulitis With Abscess: A Case Report.

BACKGROUND: Intra-abdominal desmoid-type fibromatosis (DF) rarely necessitates emergency surgery. However, the condition is difficult to diagnose preoperatively and can become life-threatening if left untreated. CASE REPORT: A 46-year-old man complained of fever and right lower quadrant pain. In computed tomography, the mesenteric side of the ascending colon demonstrated air and fluid collections, suggesting diverticulitis with abscess. After 2 weeks of conservative treatment with fasting, the patient started to consume food; nonetheless, fever returned. Colonoscopy and contrast enema detected a fistula extending from the ascending colon to the abscess, with no surrounding lesions. Surgery was then performed because the abscess was refractory. During laparotomy, the scar tissue of the abscess was found to be attached to the lateral wall of the ascending colon. Hence, right colectomy combined with abscess resection was performed. Histopathological findings revealed DF in the mesentery. CONCLUSION: Although rare, DF should be included in the preoperative differential diagnosis of intra-abdominal abscesses.

Novel Indicator to Ascertain the Status and Trend of COVID-19 Spread: Modeling Study.

BACKGROUND: In the fight against the pandemic of COVID-19, it is important to ascertain the status and trend of the infection spread quickly and accurately. OBJECTIVE: The purpose of our study is to formulate a new and simple indicator that represents the COVID-19 spread rate by using publicly available data. METHODS: The new indicator K is a backward difference approximation of the logarithmic derivative of the cumulative number of cases with a time interval of 7 days. It is calculated as a ratio of the number of newly confirmed cases in a week to the total number of cases. RESULTS: The analysis of the current status of COVID-19 spreading over countries showed an approximate linear decrease in the time evolution of the K value. The slope of the linear decrease differed from country to country. In addition, it was steeper for East and Southeast Asian countries than for European countries. The regional difference in the slope seems to reflect both social and immunological circumstances for each country. CONCLUSIONS: The approximate linear decrease of the K value indicates that the COVID-19 spread does not grow exponentially but starts to attenuate from the early stage. The K trajectory in a wide range was successfully reproduced by a phenomenological model with the constant attenuation assumption, indicating that the total number of the infected people follows the Gompertz curve. Focusing on the change in the value of K will help to improve and refine epidemiological models of COVID-19.

Most Strange Dibaryon from Lattice QCD.

The ΩΩ system in the ^{1}S_{0} channel (the most strange dibaryon) is studied on the basis of the (2+1)-flavor lattice QCD simulations with a large volume (8.1 fm)^{3} and nearly physical pion mass m_{π}≃146 MeV at a lattice spacing of a≃0.0846 fm. We show that lattice QCD data analysis by the HAL QCD method leads to the scattering length a_{0}=4.6(6)(_{-0.5}^{+1.2}) fm, the effective range r_{eff}=1.27(3)(_{-0.03}^{+0.06}) fm, and the binding energy B_{ΩΩ}=1.6(6)(_{-0.6}^{+0.7}) MeV. These results indicate that the ΩΩ system has an overall attraction and is located near the unitary regime. Such a system can be best searched experimentally by the pair-momentum correlation in relativistic heavy-ion collisions.

Fate of the Tetraquark Candidate Z_{c}(3900) from Lattice QCD.

The possible exotic meson Z_{c}(3900), found in e^{+}e^{-} reactions, is studied by the method of coupled-channel scattering in lattice QCD. The interactions among πJ/ψ, ρη_{c}, and D[over ¯]D^{*} channels are derived from (2+1)-flavor QCD simulations at m_{π}=410-700 MeV. The interactions are dominated by the off-diagonal πJ/ψ-D[over ¯]D^{*} and ρη_{c}-D[over ¯]D^{*} couplings, which indicates that the Z_{c}(3900) is not a usual resonance but a threshold cusp. Semiphenomenological analyses with the coupled-channel interaction are also presented to confirm this conclusion.

[Dedifferentiated Chondrosarcoma of the Chest Wall].

A 79-year-old man complaining of an anterior chest mass with pain had an abnormal shadow on chest X-ray. A mass, 7 cm in size, with destruction of the right 4th rib was found on chest computed tomography. A F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) corresponding to the lesion showed an abnormal accumulation of FDG with the standardized uptake value(SUV) max=16.19. A malignant tumor of the chest wall origin was suspected and the tumor was resected with the 3th, 4th, and 5th ribs. Histologically, the tumor was diagnosed as dedifferentiated chondrosarcoma. He died of local recurrence about 5 months after the operation.

[Resected Pulmonary Cryptococcosis Suspected as Lung Cancer;Report of a Case].

We report a case of pulmonary cryptococcosis suspected of lung cancer. A 65-year-old woman had an abnormal shadow on chest X-ray. A solitary nodule, 12 mm in size, with pleural indentation and spicula in S3 of the left lung was found on chest computed tomography. A serum cryptococcal antigen was negative. An abnormal accumulation of fluoro-2-deoxy-D-glucose(FDG)in the nodule was found with the standardized uptake value (SUV) max 5.04, suggesting lung cancer. The nodule was diagnosed as pulmonary cryptococcosis by surgical resection.