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We have investigated transport properties of carriers excited in high-quality homoepitaxial diamond (100) films by 5.6 eV photons or 15 keV electrons. The high-quality single-crystalline diamond films were homoepitaxially grown on type-Ib diamond substrates at a rate of 2.5 μm/h by high-power microwave-plasma chemical-vapor-deposition (MPCVD). In cathodoluminescence (CL) measurements, strong free-exciton recombination emissions were observed at room temperature from the almost whole specimen surface, indicating the grown films have substantially high quality. It is found through an analysis of the visible emission band originating from the type-Ib substrate that decay constants estimated for excited carriers were ∼5 μm in the depth direction. This is consistent with the fact that the intensity of spotlike CL images varied with an exponential function of the lateral length. From transient photocurrent measurements using ultrashort pulse laser excitations, decay times τ for the present high-quality diamond were estimated to be 15 and 100 ns for electrons and holes, respectively. Charge collection distances at an electric field E of 830 V/cm were deduced to be ∼190 μm and over 1.2 mm for electrons and holes, respectively. The former may give a high electron drift mobility of μ∼1600 cm2/Vs while the diffusion coefficients estimated for electrons are 55±14 cm2/V s, which is comparable with or even higher than those of Si. These physical quantities demonstrate high quality of the diamond films grown by means of the high-power MPCVD method. [ABSTRACT FROM AUTHOR]

To study one-dimensional (1D) quantum liquid of4 He, we measured the heat capacity and performed a torsional oscillator experiment for4 He adsorbed on a new mesoporous substrate whose adsorption area consists of walls of straight one-dimensional 18Å diameter tunnels. The presence of adsorbed quantum liquid was examined by the isotope effect on the heat capacity for3 He and4 He adatoms. Above a coverage no , the heat capacity isotherms are completely different because of the Fermi and the Bose fluids, respectively. In the torsional oscillator experiment we observed superfluid4 He above no . The fraction of the superfluid decoupled from the motion of the substrate is 0.13, which is the same order as 0.18 for packed Pt fine powder and 0.24 for 80 Å-porous glasses. The result indicates that the superfluid state exists in the one-dimensional4 He adatoms formed in the 18 Å diameter pores. [ABSTRACT FROM AUTHOR]

A multicenter, randomized, prospective trial was conducted to determine the clinical efficacy of ticlopidine, an antiplatelet agent, in the prevention of graft occlusion following vascular reconstructive surgery of the lower extremity for arteriosclerosis obliterans. Ticlopidine was administered for two years to one group of patients (112 reconstructed arterial segments) while a control group received no antithrombotic therapy (108 segments). There was no significant difference between the treated and control groups in the overall cumulative patency rates for both suprainguinal and infrainguinal reconstructions. In the treated group, however, there was a significant reduction of occlusions in pa tients with rest pain or ischemic gangrene (p < 0.1) and in those with hyperlipi demia (p < 0.05). Ticlopidine-treated patients with infrainguinal arterial reconstructions developed more occlusions than controls between three and twelve months after surgery, but the controls had more occlusions both immedi ately after surgery and in the second postoperative year. It appeared, therefore, that ticlopidine reduced graft failure due to neointimal fibrous hyperplasia or progression of the underlying condition but caused an adverse effect by delaying graft healing. The clinical usefulness of antiplatelet therapy is limited, but it may be effective in the prevention of graft occlusion when administered to the selected patient groups above mentioned. Controversy about antiplatelet ther apy and future research on adjuvant drug therapy after arterial reconstruction are discussed. [ABSTRACT FROM PUBLISHER]

The sweetpotato whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is challenging to control using chemical pesticides owing to its resistance to many insecticides. Thus, there has been an increasing demand for alternative control measures. Thus, this study evaluated the efficacy of a newly designed pest suction machine to manage whiteflies on tomato plants (Solanum lycopersicum L.) (Solanales: Solanaceae) in greenhouses over 2 seasons. The suction machine comprised a battery-powered cart with a mounted suction unit, an ultrasonic device, and green lights. Ultrasonic irradiation provided non-contact vibration, facilitating the movement of adult whiteflies away from the plants, and green lights attracted them to the suction device. This combination effectively captured whitefly adults, even with a weak suction force, saving electricity consumption. The efficacy of suction machine was further evaluated by measuring the number of whitefly adults caught by the machine and the number of adults and nymphs remaining on the tomato leaves. The whitefly population was considerably lower in the treated blocks than in the non-treated blocks in the autumn trial. The machine reduced the density of whitefly adults without using chemical pesticides. Although a lot of optimizations would be required, suction control is an additional and alternative strategy that may be incorporated in the integrated pest management of whiteflies on greenhouse tomato plants., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

The interaction between a metal and a support, which is known as the metal-support interaction, often plays a determining role in the catalytic properties of supported metal catalysts. Herein, we have developed model Pt/CeO 2 catalysts, which enabled us to investigate the interface atomic and electronic structures between Pt and the {001}, {011}, and {111} planes of CeO 2 using scanning transmission electron microscopy and electron energy-loss spectroscopy. We found that the number of Ce 3+ ions around the Pt nanoparticles followed the order {001} > {011} > {111}, which was the opposite order of the generally accepted stability of low index surfaces of CeO 2 . Systematic first-principles calculations revealed that the presence of Pt nanoparticles facilitated the formation of oxygen vacancies and that the appearance of the Pt δ+ state was preferred when Pt nanoparticles were in contact with CeO 2 {001} planes due to direct charge transfer from Pt to CeO 2 . These results provide important insights into the nature of the metal-support interaction for a comprehensive understanding of the properties of supported metal catalysts.

Background: Spinal cord injury (SCI) is a devastating disease that results in permanent paralysis. Currently, there is no effective treatment for SCI, and it is important to identify factors that can provide therapeutic intervention during the course of the disease. Zinc, an essential trace element, has attracted attention as a regulator of inflammatory responses. In this study, we investigated the effect of zinc status on the SCI pathology and whether or not zinc could be a potential therapeutic target., Methods: We created experimental mouse models with three different serum zinc concentration by changing the zinc content of the diet. After inducing contusion injury to the spinal cord of three mouse models, we assessed inflammation, apoptosis, demyelination, axonal regeneration, and the number of nuclear translocations of NF-κB in macrophages by using qPCR and immunostaining. In addition, macrophages in the injured spinal cord of these mouse models were isolated by flow cytometry, and their intracellular zinc concentration level and gene expression were examined. Functional recovery was assessed using the open field motor score, a foot print analysis, and a grid walk test. Statistical analysis was performed using Wilcoxon rank-sum test and ANOVA with the Tukey-Kramer test., Results: In macrophages after SCI, zinc deficiency promoted nuclear translocation of NF-κB, polarization to pro-inflammatory like phenotype and expression of pro-inflammatory cytokines. The inflammatory response exacerbated by zinc deficiency led to worsening motor function by inducing more apoptosis of oligodendrocytes and demyelination and inhibiting axonal regeneration in the lesion site compared to the normal zinc condition. Furthermore, zinc supplementation after SCI attenuated these zinc-deficiency-induced series of responses and improved motor function., Conclusion: We demonstrated that zinc affected axonal regeneration and motor functional recovery after SCI by negatively regulating NF-κB activity and the subsequent inflammatory response in macrophages. Our findings suggest that zinc supplementation after SCI may be a novel therapeutic strategy for SCI., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Kijima, Ono, Kobayakawa, Saiwai, Hara, Yoshizaki, Yokota, Saito, Tamaru, Iura, Haruta, Kitade, Utsunomiya, Konno, Edgerton, Liu, Sakai, Maeda, Kawaguchi, Matsumoto, Okada and Nakashima.)

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is an autoimmune disorder sometimes accompanied by ovarian teratoma. However, the concept of encephalitis without anti-NMDAR antibodies successfully treated with ovarian teratoma resection and immunotherapy has not been established. We herein report two such cases. Case 1 exhibited delayed magnetic resonance imaging abnormalities in the thalamus and basal ganglia, despite clinical improvement. Case 2 presented with brainstem encephalitis similar to Bickerstaff's encephalitis. Although both patients tested negative for anti-NMDAR antibodies, the recovery of the neurological function and good prognosis following tumor resection with immunotherapy indicated a close association between these diseases and ovarian teratoma.

Spinal cord injury (SCI) causes reactive astrogliosis, the sequential phenotypic change of astrocytes in which naïve astrocytes (NAs) transform into reactive astrocytes (RAs) and subsequently become scar-forming astrocytes (SAs), resulting in glial scar formation around the lesion site and thereby limiting axonal regeneration and motor/sensory functional recovery. Inhibiting the transformation of RAs into SAs in the acute phase attenuates the reactive astrogliosis and promotes regeneration. However, whether or not SAs once formed can revert to RAs or SAs is unclear. We performed selective isolation of astrocytes from glial scars at different time points for a gene expression analysis and found that the expression of Sox9, an important transcriptional factor for glial cell differentiation, was significantly increased in chronic phase astrocytes (CAs) compared to SAs in the sub-acute phase. Furthermore, CAs showed a significantly lower expression of chondroitin sulfate proteoglycan (CSPG)-related genes than SAs. These results indicated that SAs changed their phenotypes according to the surrounding environment of the injured spinal cord over time. Even though the integrin-N-cadherin pathway is critical for glial scar formation, collagen-I-grown scar-forming astrocytes (Col-I-SAs) did not change their phenotype after depleting the effect of integrin or N-cadherin. In addition, we found that Col-I-SAs transplanted into a naïve spinal cord formed glial scar again by maintaining a high expression of genes involved in the integrin-N-cadherin pathway and a low expression of CSPG-related genes. Interestingly, the transplanted Col-I-SAs changed NAs into SAs, and anti-β 1 -integrin antibody blocked the recruitment of SAs while reducing the volume of glial scar in the chronic phase. Our findings indicate that while the characteristics of glial scars change over time after SCI, SAs have a cell-autonomous function to form and maintain a glial scar, highlighting the basic mechanism underlying the persistence of glial scars after central nervous system injury until the chronic phase, which may be a therapeutic target., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Introduction: Limited and inconclusive evidence for the association of dietary potassium intake with serum potassium in chronic kidney disease (CKD) patients have been shown, though restricting dietary potassium has been recommended for CKD patients to prevent hyperkalemia. Multiple 24-hour urine collections are necessary to adequately assess potassium intake. We investigated associations of 24-hour urinary potassium excretion (UKV) with serum potassium in CKD outpatients based on multiple 24-hour urine collections., Methods: This retrospective cohort study was based on outpatients with CKD stages G3 to G5, median age of 72.0 years; and median follow-up of 3.9 months and 8.9 months, respectively, for analyses using 3-time measurement ( N  = 290 and 870 observations) and 7-time measurements ( N  = 220 and 1540 observations). The outcome was serum potassium., Results: Multivariable-adjusted mean difference in serum potassium (mEq/l) and odds ratio of hyperkalemia per 10 mEq/d increase in UKV were, respectively, 0.12 (95% confidence interval [CI]: 0.09-0.15) and 2.15 (1.70-2.73) in generalized estimating equations (GEEs) with 3-time measurements. The mean difference became more pronounced as CKD stages progressed: 0.08 (0.05-0.12), 0.12 (0.08-0.16), and 0.16 (0.12-0.20) for CKD G3, G4, and G5. Similar results were obtained from analyses using 7-time measurements and hierarchical Bayesian measurement error models treating measurement error of UKV adequately., Conclusion: We suggest significant but weak associations (R 2 : 0.08, 0.14, and 0.18 for CKD G3, G4, and G5) between serum potassium and dietary potassium intake estimated by multiple 24-hour urine collections in CKD patients. Further studies are needed to validate nutritional and clinical aspects of the associations., (© 2022 Published by Elsevier Inc. on behalf of the International Society of Nephrology.)

Understanding the nature of the interaction between a metal and support, which is known as the metal-support interaction, in supported metal catalysts is crucial to design catalysts with desired properties. Here, we have developed model Pt/TiO 2 catalysts based on the deposition of colloidal Pt nanoparticles and studied their atomic and electronic structures before and after a postdeposition treatment that induces catalytic activity using aberration-corrected scanning transmission electron microscopy, electron energy loss spectroscopy, and first-principles calculations. Direct contact between Pt nanoparticles and TiO 2 is realized after the postdeposition treatment, which is accompanied by the formation of a Ti 3+ state on the TiO 2 surface close to the Pt nanoparticles and a Pt δ+ state on the Pt nanoparticles. The origin of these two states and their effect on the catalytic properties are discussed. These findings pave the way for a comprehensive understanding of metal-support interactions in supported metal catalysts.

Multiple 24-hour urine collections are necessary to adequately assess sodium and potassium intake. Here, we assessed kidney function decline for four years after baseline in relation to seven-time averaged 24-hour urinary sodium and potassium excretion (UNaV, UKV), their UNaV/UKV ratio, and their categorical combination in outpatients with chronic kidney disease (CKD). This retrospective cohort study was based on 240 outpatients with baseline CKD stages 3-5, baseline age 20 years or more (median age 72.0 years), and a median follow-up (with interquartile range) of 2.9 (1.4-4.0) years. Outcome was the percentage change in annual slope of estimated glomerular filtration rate (delta eGFR per year). In linear mixed models, percentage changes in delta eGFR per year were -3.26% (95% confidence interval -5.85 to -0.60), +5.20% (2.34 to 8.14), and -5.20% (-7.64 to -2.69), respectively, per one standard deviation increase in the seven-time averaged UNaV and UKV, and their UNaV/UKV ratio. Additionally, percentage changes per year in delta eGFR per year were -16.27% (-23.57 to -8.27) in the middle-to-high UNaV and low UKV group, compared with the low UNaV and middle-to high UKV group. Thus, our study reinforces the observation of opposite associations between GFR decline and urinary excretion rates of sodium (positive) and potassium (negative), respectively. Whether changes in dietary sodium and potassium intake slow GFR decline still requires further study., (Copyright © 2021 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.)

Introduction: Facet joints are anatomical structures that are known to be crucial for determining spinal biomechanical motion; however, the potential relationship between facet orientation and the development of cervical spondylolisthesis remains unclear. Thus, in this study, we aimed to explore the relationship between facet orientation and cervical spondylolisthesis as well as myelopathy., Methods: Facet orientation in the cervical spine was investigated using computed tomography in 103 patients with cervical myelopathy, and facet inclination was measured on axial, coronal, and sagittal reconstructed images. Patients were divided into anterolisthesis, retrolisthesis, and no spondylolisthesis groups at each intervertebral level (C2/3-C6/7 levels)., Results: Facet joints in the anterolisthesis and retrolisthesis groups tended to slope posterolaterally and downward laterally compared with those in the no spondylolisthesis group at C3/4, C4/5, and C5/6 levels (P<0.001)., Conclusions: The posterolaterally oriented and laterally downward sloping facet at C3/4 and C4/5 levels may be a risk factor for the development of cervical spondylolisthesis as well as symptomatic myelopathy., Competing Interests: Conflicts of Interest: The authors declare that there are no relevant conflicts of interest., (Copyright © 2022 by The Japanese Society for Spine Surgery and Related Research.)