Nb-doped TiO2 air-electrode for advanced Li-air batteries

As new substrate materials to replace a conventional carbon substrate, TiO2 and Nb-doped TiO2 air-electrodes for Li-air batteries were investigated. Through a simple two-step process, we successfully synthesized anatase Nb-doped TiO2 nanoparticles and demonstrated the potential applicability of TiO2-based materials for use in Li-air battery electrode. An air-electrode with Nb-doped TiO2 nanoparticles could deliver a higher discharge capacity than a bare TiO2 electrode due to the enhanced conductivity, which implies the importance of facile electron transport during the discharge process. © 2014 The Ceramic Society of Japan and the Korean Ceramic Society.

Nanopores of carbon nanotubes as practical hydrogen storage media

We report on hydrogen desorption mechanisms in the nanopores of multiwalled carbon nanotubes (MWCNTs). The as-grown MWCNTs show continuous walls that do not provide sites for hydrogen storage under ambient conditions. However, after treating the nanotubes with oxygen plasma to create nanopores in the MWCNTs, we observed the appearance of a new hydrogen desorption peak in the 300–350 K range. Furthermore, the calculations of density functional theory and molecular dynamics simulations confirmed that this peak could be attributed to the hydrogen that is physically adsorbed inside nanopores whose diameter is approximately 1 nm. Thus, we demonstrated that 1 nm nanopores in MWCNTs offer a promising route to hydrogen storage media for onboard practical applications

Advanced virtual monoenergetic imaging algorithm for lower extremity computed tomography angiography: effects on image quality, artifacts, and peripheral arterial disease evaluation

PURPOSETo investigate the image quality of lower extremity computed tomography angiography (LE-CTA) using a reconstruction algorithm for monoenergetic images (MEIs) to evaluate peripheral arterial disease (PAD) at different kiloelectron volt (keV) levels.METHODSA total of 146 consecutive patients who underwent LE-CTA on a dual-energy scanner to obtain MEIs at 40, 50, 60, 70, and 80 keV were included. The overall image quality, segmental image quality of the arteries and PAD segments, venous contamination, and metal artifacts from prostheses, which may compromise quality, were analyzed.RESULTSThe mean overall image quality of each MEI was 2.9 ± 0.7, 3.6 ± 0.6, 3.9 ± 0.3, 4.0 ± 0.2, and 4.0 ± 0.2 from 40 to 80 keV, respectively. The segmental image quality gradually increased from 40 to 70–80 keV until reaching its highest value. Among 295 PAD segments in 68 patients, 40 (13.6%) were scored at 1–2 at 40 keV and 13 (4.4%) were scored at 2 at 50 keV, indicating unsatisfactory image quality due to the indistinguishability between high-contrast areas and arterial calcifications. The segments exhibiting metal artifacts and venous contamination were reduced at 70–80 keV (2.6 ± 1.2, 2.7 ± 0.5) compared with at 40 keV (2.4 ± 1.1, 2.5 ± 0.7).CONCLUSIONThe LE-CTA method using a reconstruction algorithm for MEIs at 70–80 keV can enhance the image quality for PAD evaluation and improve mitigate venous contamination and metal artifacts

Ternary full adder using multi-threshold voltage graphene barristors

Ternary logic circuit has been studied for several decades because it can provide simpler circuits and subsequently lower power consumption via succinct interconnects. We demonstrated a ternary full adder exhibiting a low power-delay-product of ~10-16 J, which is comparable with the binary equivalent circuit. The ternary full adder was modeled using device parameters extracted from the experimentally demonstrated multi-Vth ternary graphene barristors

Infections after Living Donor Liver Transplantation in Children

The aim of this study was to evaluate the infectious complications after living donor liver transplantation (LDLT) in children. We enrolled 95 children (38 boys and 57 girls) who underwent LDLT from 1994 to 2004. The median age was 22 months (range, 6 months to 15 yr). We retrospectively investigated the proven episodes of bacterial, viral, and fungal infection. There occurred 150 infections in 67 (70%) of 95 patients (1.49 infections/patient); 74 in 43 patients were bacterial, 2 in 2 were fungal, and 74 in 42 were viral. The most common sites of bacterial infection were the bloodstream (33%) and abdomen (25%). Most of the bacterial infections occurred within the first month after LDLT. Bacterial and fungal infections did not result in any deaths. The most common causes of viral infection were Epstein-Barr virus in 37 patients and cytomegalovirus in 18. Seven of the 14 deaths after LDLT were associated with viral infection. Our study suggests that infection is one of the important causes of morbidity and mortality after LDLT. Especially careful monitoring and management of viral infections is crucial for improving the outcome of LDLT in children

Composite scoring system and optimal tumor budding cut-off number for estimating lymph node metastasis in submucosal colorectal cancer

Background Tumor budding is associated with lymph node (LN) metastasis in submucosal colorectal cancer (CRC). However, the rate of LN metastasis associated with the number of tumor buds is unknown. Here, we determined the optimal tumor budding cut-off number and developed a composite scoring system (CSS) for estimating LN metastasis of submucosal CRC. Methods In total, 395 patients with histologically confirmed T1N0–2M0 CRC were evaluated. The clinicopathological characteristics were subjected to univariate and multivariate analyses. The Akaike information criterion (AIC) values of the multivariate models were evaluated to identify the optimal cut-off number. A CSS for LN metastasis was developed using independent risk factors. Results The prevalence of LN metastasis was 13.2%. Histological differentiation, lymphatic or venous invasion, and tumor budding were associated with LN metastasis in univariate analyses. In multivariate models adjusted for histological differentiation and lymphatic or venous invasion, the AIC value was lowest for five tumor buds. Unfavorable differentiation (odds ratio [OR], 8.16; 95% confidence interval [CI], 1.80–36.89), lymphatic or venous invasion (OR, 5.91; 95% CI, 2.91–11.97), and five or more tumor buds (OR, 3.01; 95% CI, 1.21–7.69) were independent risk factors. In a CSS using these three risk factors, the rates of LN metastasis were 5.6%, 15.5%, 31.0%, and 52.4% for total composite scores of 0, 1, 2, and ≥ 3, respectively. Conclusions For the estimation of LN metastasis in submucosal CRC, the optimal tumor budding cut-off number was five. Our CSS can be utilized to estimate LN metastasis.This work was supported by the Korean government (MSIT) Grant No. 2021R1F1A1063000 from the National Research Foundation of Korea (NRF)