Nitrogen doping of carbon nanoelectrodes for enhanced control of DNA translocation dynamics

Controlling the dynamics of DNA translocation is a central issue in the emerging nanopore-based DNA sequencing. To address the potential of heteroatom doping of carbon nanostructures to achieve this goal, herein we carry out atomistic molecular dynamics simulations for single-stranded DNAs translocating between two pristine or doped carbon nanotube (CNT) electrodes. Specifically, we consider the substitutional nitrogen doping of capped CNT (capCNT) electrodes and perform two types of molecular dynamics simulations for the entrapped and translocating single-stranded DNAs. We find that the substitutional nitrogen doping of capCNTs stabilizes the edge-on nucleobase configurations rather than the original face-on ones and slows down the DNA translocation speed by establishing hydrogen bonds between the N dopant atoms and nucleobases. Due to the enhanced interactions between DNAs and N-doped capCNTs, the duration time of nucleobases within the nanogap was extended by up to ~ 290 % and the fluctuation of the nucleobases was reduced by up to ~ 70 %. Given the possibility to be combined with extrinsic light or gate voltage modulation methods, the current work demonstrates that the substitutional nitrogen doping is a promising direction for the control of DNA translocation dynamics through a nanopore or nanogap based of carbon nanomaterials.Comment: 11 pages, 4 figure

GPS-GLASS: Learning Nighttime Semantic Segmentation Using Daytime Video and GPS data

Semantic segmentation for autonomous driving should be robust against various in-the-wild environments. Nighttime semantic segmentation is especially challenging due to a lack of annotated nighttime images and a large domain gap from daytime images with sufficient annotation. In this paper, we propose a novel GPS-based training framework for nighttime semantic segmentation. Given GPS-aligned pairs of daytime and nighttime images, we perform cross-domain correspondence matching to obtain pixel-level pseudo supervision. Moreover, we conduct flow estimation between daytime video frames and apply GPS-based scaling to acquire another pixel-level pseudo supervision. Using these pseudo supervisions with a confidence map, we train a nighttime semantic segmentation network without any annotation from nighttime images. Experimental results demonstrate the effectiveness of the proposed method on several nighttime semantic segmentation datasets. Our source code is available at https://github.com/jimmy9704/GPS-GLASS.Comment: ICCVW 202

Malignancies in Korean Patients with Inflammatory Myopathy

The aim of this study was to assess the prevalence and the common type of malignancies in Korean patients with polymyositis (PM) and dermatomyositis (DM) and to evaluate the differences of clinical and laboratory findings between patients with malignancy and those without malignancy. Forty-one Korean patients, who were diagnosed as PM or DM, were enrolled in this study. They fulfilled the Bohan and Peter's criteria for a definite diagnosis of PM and DM. Patients with PM were 25 and those with DM were 16. Eleven out of 41 patients (26.8%) had malignancies. The malignancy was diagnosed simultaneously or later in 81.8% of patients with inflammatory myopathy (IM). The breast cancer was the most common malignancy. In this study, forty three years old as a screening age for malignancy had 88.9% sensitivity and 50.2% specificity. The serum levels of creatine kinase (CK) were significantly lower in patients with malignancy than those without malignancy

Effect of accumulated vs continuous exercise on excess post-exercise oxygen consumption

Background: A continuous aerobic exercise program is an effective method of improving calorie consumption on the metabolism of skeletal muscle. However, studies report that accumulated exercise of 30 minutes divided into three sessions of 10 minutes is as effective as one continuous exercise session for 30 minutes. As yet, no study has compared the excess post-exercise oxygen consumption associated with accumulated exercise and continuous exercise over these timeframes. Objective: The primary purpose of this study was to compare the excess post-exercise oxygen consumption associated with performing continuous exercise for 30 minutes and three sessions of accumulated exercise for 10 minutes at the same intensity of 60% VO2max. Method: Posters about the study were posted on the February 2019 Konkuk university homepage and bulletin board, and a total of 34 college students (males, n=18; females, n=16) volunteered to participate. Using a balanced repeated-measures crossover design, the subjects randomly took two exercises: continuous exercise (1 x 30 minutes) or accumulated exercise (3 x 10 minutes), and the washout period between the two exercises was a week. All exercises were performed using an ergometer at 60% maximal oxygen consumption. Oxygen consumption and heart rate were monitored and measured during exercise and after exercise. Lipid profile and lactate acid were measured at rest, exercise end, exercise end plus 30 minutes, and exercise end plus 60 minutes. IBM SPSS Statistics 23 was used to perform a paired t-test, and the statistically significant difference was set at <.05. Results: Excess post-exercise oxygen consumption parameters (e.g., total oxygen consumption, total calorie, and summation of heart rate) were higher in accumulated exercise than in continuous exercise (p<.05). No significant difference in the calorie during exercise between CEx and AEx (p = .140). No significant difference was observed in the lipid profile between accumulated exercise and continuous exercise (p>.05). No significant differences were observed at rest, exercise end plus 30 minutes, exercise end plus 60 minutes in lactic acid in the blood (p <.05). However, at exercise end, it was significantly higher in the accumulated exercise (p<.01). Conclusions: This study confirmed that after equalizing energy expenditure for continuous exercise and accumulated exercise in participants in their 20s, accumulated exercise results in higher excess post-exercise oxygen consumption than continuous exercise. The data suggests that accumulated exercise may be more effective in reducing body fat than continuous exercise for a given amount of energy expenditure. [Ethiop.J. Health Dev. 2020;34(Special issue-3):84-90] Keywords: Continuous exercise, accumulated exercise, excess post-exercise oxygen consumptio

Effects on Growth and Osteogenic Differentiation of Mesenchymal Stem Cells by the Zinc-Added Sol-Gel Bioactive Glass Granules

Responses of mesenchymal stem cells (MSCs) cultured with zinc-added (2 and 5%) bioactive glass granules were evaluated in terms of cell growth and osteogenic differentiation. MSCs were cultured with different quantities (3, 10 and 30) of glass granules for up to 21 days in the osteogenic medium. Cell growth was stimulated by a small quantity of glasses, particularly those that contained zinc. Osteogenic differentiation, as assessed by alkaline phosphatase activity (ALP) activity, was significantly enhanced by the glasses, particularly with large quantities of glass and for prolonged culturing. Expression of bone-sialo protein (BSP) was significantly up-regulated around the bioactive glass granules. Moreover, the zinc addition significantly altered the ALP and BSP depending on the culture time and glass quantity. Cellular mineralization was improved in all glass samples, and particularly in the 2% zinc-glass. Taken together, the zinc addition to bioactive glass induced the MSCs growth and their osteogenic differentiation, at least to the level of zinc-free glass, and with even higher level observed depending on the quantity and culture time. These findings indicate that the zinc addition to bioactive glass may be useful in development of biomaterials for the stimulation of adult stem cell in bone tissue engineering

Inhomogeneous Defect Distribution in Mixed-Polytype Metal Halide Perovskites

The competition between corner, edge and face-sharing octahedral networks is a cause of phase inhomogeneity in metal halide perovskite thin-films. Here we probe the charged iodine vacancy distribution and transport at the junction between cubic and hexagonal polytypes of CsPbI$_3$ from first-principles materials modelling. We predict a lower defect formation energy in the face-sharing regions, which correlates with a longer Pb$-$I bond length and causes a million-fold increase in local defect concentration. These defects are predicted to be more mobile in the face-sharing regions with a reduced activation energy for vacancy-mediated diffusion. We conclude that hexagonal phase inclusions or interfaces will act as defect sinks that could trap charges and enhance current-voltage hysteresis in perovskite-based solar cells and electrical devices