112 research outputs found
Diffusion behavior of delta-doped Si in InAlAs/InP heterostructures
Diffusion behavior of delta-doped Si in InAlAs and InP was studied by using secondary ion mass spectroscopy. A significant broadening of the profile due to postgrowth annealing was observed in In0.52Al0.48As. In contrast, the depth profile of delta-doped Si in InP was scarcely changed by annealing. This indicates that the diffusion coefficient of delta-doped Si in InP is much smaller than that in In0.52Al0.48As. Suppression of Si diffusion by using a delta-doped InP layer as the carrier supply layer (CSL) improves the thermal stability of the InP-HEMT structures
Concomitant vancomycin and piperacillin/tazobactam treatment is associated with an increased risk of acute kidney injury in Japanese patients
Introduction
Recent studies have corroborated that the co-administration of vancomycin (VCM) and piperacillin/tazobactam (PT) is correlated with an increased incidence of acute kidney injury (AKI). However, evidence directed at the Japanese population is scarce. Therefore, we conducted a retrospective study to compare the occurrence of AKI among Japanese patients who received VCM with PT (VP therapy) and VCM with another β-lactams (VA therapy).
Methods
The present study, performed at Tsuyama Chuo Hospital between June 2012 and December 2018, included adult patients who received VCM and β-lactam antibiotics for ≥48 h. We defined the primary outcome as the incidence of AKI based on the risk, injury, failure, loss, and end-stage kidney disease criteria. Patients' clinical characteristics and outcomes were reviewed and compared between the two groups with univariate and multivariate logistic regression analyses. Subgroup analysis was conducted by stratifying the patients’ baseline hospital admittance status, as intensive care unit or general wards.
Results
We analyzed 272 patients (92 V P therapy and 180 VA therapy). Univariate analysis revealed a significant difference in AKI development between VP and VA therapy (25.0% vs 12.2%; p
Conclusion
VP therapy was associated with an increased risk of AKI compared to that with VA therapy among the Japanese population
Precipitable Water Vapor Measurement using GNSS Data in the Atacama Desert for Millimeter and Submillimeter Astronomical Observations
Precipitable water vapor (PWV) strongly affects the quality of data obtained
from millimeter- and submillimeter-wave astronomical observations, such as
those for cosmic microwave background (CMB) measurements. Some of these
observatories have used radiometers to monitor PWV. In this study, PWV was
measured from April 2021 to April 2022 using Global Navigation Satellite System
(GNSS) instruments in the Atacama Desert, Chile, where several millimeter and
submillimeter-wave telescopes are located. We evaluated the accuracy of these
measurements by comparing them to radiometer measurements. We calculated the
PWV from GNSS data using Canadian Spatial Reference System Precise Point
Positioning (CSRS-PPP), an online software package. When using GNSS data alone,
the estimated PWV showed a systematic offset of +1.08 mm. When combining GNSS
data with data from a barometer which was co-located with the GNSS receiver,
the estimated PWV showed a lower systematic offset of -0.14 mm. The GNSS PWV
showed a statistical error of 0.52 mm with an averaging time of an hour.
Compared to other PWV measurement methods, GNSS instruments are robust in bad
weather conditions, have sufficient time resolution, and are less expensive. By
demonstrating good accuracy and precision in low PWV conditions, this paper
shows that GNSS instruments are valuable tools for PWV measurements for
observing site evaluation and data analysis for ground-based telescopes
Image Reproduction based on Texture Image Extension with Traced Drawing for Heavy Damaged Mural Painting
AbstractNot only geometric information but also optical information is needed to reproduce ruins using three-dimensional realistic computer graphics as they were when those were founded. In order to give a model a sense of reality, it is common to carry out the texture mapping of the photographed image. However such information can not be acquired from either weathered or partially destroyed ruins. While there are various conventional techniques for image restoration, which can overcome in the case of small missing and cracks, it is difficult to restore such a heavy damaged mural painting well when there is no information from the periphery.In this paper, we propose an image reproduction of a heavy damaged mural painting using a texture information extracted from another mural painting which has actually been restored by conservators and a traced drawing which the specialist guessed and drew. The restored image was used same pigment inks. Based on texture information from the restored image and a segmented traced drawing, we produce a restored image by applying the texture extension to each segment
Synthesis of tertiary alkylphosphonate oligonucleotides through light-driven radical-polar crossover reactions
光エネルギーで新しい化学修飾核酸を合成 --核酸リン原子の第三級アルキル化に成功--. 京都大学プレスリリース. 2023-11-01.Chemical modification of nucleotides can improve the metabolic stability and target specificity of oligonucleotide therapeutics, and alkylphosphonates have been employed as charge-neutral replacements for naturally-occurring phosphodiester backbones in these compounds. However, at present, the alkyl moieties that can be attached to phosphorus atoms in these compounds are limited to methyl groups or primary/secondary alkyls, and such alkylphosphonate moieties can degrade during oligonucleotide synthesis. The present work demonstrates the tertiary alkylation of the phosphorus atoms of phosphites bearing two 2’-deoxynuclosides. This process utilizes a carbocation generated via a light-driven radical-polar crossover mechanism. This protocol provides tertiary alkylphosphonate structures that are difficult to synthesize using existing methods. The conversion of these species to oligonucleotides having charge-neutral alkylphosphonate linkages through a phosphoramidite-based approach was also confirmed in this study
Application of Heavy-Metal-Free Pd/C Catalyst for the Oxidative Dehydrogenation of Sodium Lactate to Pyruvate in an Aqueous Phase under Pressurized Oxygen
According to previous reports, the oxidative dehydrogenation of lactic acid to pyruvic acid in an aqueous phase does not proceed with Pd/C, while Pd/C doped with Te or Pb has catalytic activity at atmospheric pressure and 363 K in an aqueous NaOH solution at a pH of 8. Since use of heavy metals, such as Te or Pb, is inconsistent with green chemistry, a heavy-metal-free Pd/C catalyst is employed in the present study. The oxidative dehydrogenation of sodium lactate to sodium pyruvate in an aqueous phase at 358 K under pressurized oxygen at 1 MPa proceeded favorably using Pd/C with no adjustment of solution pH. Under pressurized oxygen, the catalytic activity of Pd/C was similar to that of Pd/C doped with either Te or Pb. This result suggests that a heavy-metal-free Pd/C catalytst might also be applied to other catalytic reactions. As an alternative to doping Pd/C with Te or Pb, the dissolution of gaseous oxygen into the reaction solution significantly enhanced the catalytic activity of Pd/C. To show the contribution of the dissolution of gaseous oxygen, the effects of the volume of oxygen in the reactor (stainless autoclave) on the reaction rate and the activity were examined. The activation parameters thus obtained reveal that the volume of oxygen in the reactor is a more important determinant of catalytic activity than the activation of the reaction itself
Triplon band splitting and topologically protected edge states in the dimerized antiferromagnet
The search for topological insulators has been actively promoted in the field
of condensed matter physics for further development in energy-efficient
information transmission and processing. In this context, recent studies have
revealed that not only electrons but also bosonic particles such as magnons can
construct edge states carrying nontrivial topological invariants. Here we
demonstrate topological triplon bands in the spin-1/2 two-dimensional dimerized
quantum antiferromagnet BaCuSiOCl, which is closely related to
a pseudo-one-dimensional variant of the Su-Schrieffer-Heeger (SSH) model,
through inelastic neutron scattering experiments. The excitation spectrum
exhibits two triplon bands and a clear band gap between them due to a small
alternation in interdimer exchange interactions along the -direction, which
is consistent with the crystal structure. The presence of topologically
protected edge states is indicated by a bipartite nature of the lattice.Comment: 15 pages, 8 figure
Serum Mac-2 binding protein glycosylation isomer and galectin-3 levels in adult-onset Still’s disease and their association with cytokines
BackgroundAutoinflammation with cytokine dysregulation may be implicated in the pathophysiology of adult-onset Still’s disease (AOSD); however, the relationship between galectins and cytokines in patients with active AOSD remains unknown. We aimed to examine the relationship between circulating cytokines/chemokines and galectin-3 (Gal-3) or its ligand, Mac-2 binding protein glycosylation isomer (M2BPGi), in Japanese patients with AOSD.MethodsWe recruited 44 consecutive patients diagnosed with AOSD according to the Yamaguchi criteria, 50 patients with rheumatoid arthritis (RA) as disease controls, and 27 healthy participants. Serum M2BPGi levels were directly measured using a HISCL M2BPGi reagent kit and an automatic immunoanalyzer (HISCL-5000). Serum Gal-3 concentrations were measured by enzyme-linked immunosorbent assay. The serum levels of 69 cytokines were analyzed in patients with AOSD using a multi-suspension cytokine array. We performed a cluster analysis of each cytokine expressed in patients with AOSD to identify specific molecular networks.ResultsSignificant increases in the serum concentrations of Gal-3 and M2BPGi were found in the serum of patients with AOSD compared with patients with RA and healthy participants (both p <0.001). There were significant positive correlations between serum Gal-3 levels and AOSD disease activity score (Pouchot score, r=0.66, p <0.001) and serum ferritin levels. However, no significant correlations were observed between serum M2BPGi levels and AOSD disease activity scores (Pouchot score, r = 0.32, p = 0.06) or serum ferritin levels. Furthermore, significant correlations were observed between the serum levels of Gal-3 and various inflammatory cytokines, including interleukin-18, in patients with AOSD. Immunosuppressive treatment in patients with AOSD significantly reduced serum Gal-3 and M2BPGi levels (p = 0.03 and 0.004, respectively).ConclusionsAlthough both Gal-3 and M2BPGi were elevated in patients with AOSD, only Gal-3 was a useful biomarker for predicting disease activity in AOSD. Our findings suggest that circulating Gal-3 reflects the inflammatory component of AOSD, which corresponds to proinflammatory cytokine induction through inflammasome activation cascades
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