The Spatially Resolved Properties of the GW170817 Host Galaxy

GW170817 is the unique gravitational-wave (GW) event that is associated to the electromagnetic (EM) counterpart GRB 170817A. NGC 4993 is identified as the host galaxy of GW170817/GRB 170817A. In this paper, we particularly focus on the spatially resolved properties of NGC 4993. We present the photometric results from the comprehensive data analysis of the high spatial-resolution images in the different optical bands. The morphological analysis reveals that NGC 4993 is a typical early-type galaxy without significant remnants of major galaxy merger. The spatially resolved stellar population properties of NGC 4993 suggest that the galaxy center has passive evolution with the outskirt formed by gas accretion. We derive the merging rate of the compact object per galaxy by a co-evolution scenario of supermassive black hole and its host galaxy. If the galaxy formation is at redshift 1.0, the merging rate per galaxy is $3.2\times 10^{-4}$ to $7.7\times 10^{-5}$ within the merging decay time from 1.0 to 5.0 Gyr. The results provide the vital information for the ongoing GW EM counterpart detections. The HST data analysis presented in this paper can be also applied for the Chinese Space Station Telescope (CSST) research in the future.Comment: RAA accepte

Thermomechanical property of rice kernels studied by DMA

The thermomechanical property of the rice kernels was investigated using a dynamic mechanical analyzer (DMA). The length change of rice kernels with a loaded constant force along the major axis direction was detected during temperature scanning. The thermomechanical transition occurred in rice kernels when heated. The transition temperatures were determined as 47°C, 50°C and 56°C for the medium-grain rice with the moisture contents of 18.1%, 16.0% and 12.5% (wet basis), respectively. Length change of the rice kernels increased with the increase of the temperature and moisture content. Among the four rice varieties investigated, the results showed that the thermomechanical property was not significantly affected by variety

Poly(benzimidazobenzophenanthroline)-Ladder-Type Two-Dimensional Conjugated Covalent Organic Framework for Fast Proton Storage

Electrochemical proton storage plays an essential role in designing next-generation high-rate energy storage devices, e.g., aqueous batteries. Two-dimensional conjugated covalent organic frameworks (2D c-COFs) are promising electrode materials, but their competitive proton and metal-ion insertion mechanisms remain elusive, and proton storage in COFs is rarely explored. Here, we report a perinone-based poly(benzimidazobenzophenanthroline) (BBL)-ladder-type 2D c-COF for fast proton storage in both a mild aqueous Zn-ion electrolyte and strong acid. We unveil that the discharged C−O− groups exhibit largely reduced basicity due to the considerable π-delocalization in perinone, thus affording the 2D c-COF a unique affinity for protons with fast kinetics. As a consequence, the 2D c-COF electrode presents an outstanding rate capability of up to 200 A g−1 (over 2500 C), surpassing the state-of-the-art conjugated polymers, COFs, and metal–organic frameworks. Our work reports the first example of pure proton storage among COFs and highlights the great potential of BBL-ladder-type 2D conjugated polymers in future energy devices

Ubiquitin-specific peptidase 39 regulates the process of proliferation and migration of human ovarian cancer via p53/p21 pathway and EMT.

Ovarian cancer is one of the most lethal gynecological cancers; owning to its late detection and chemoresistance, understanding the pathogenesis of this malignant tumor is much critical. Previous studies have reported that ubiquitin-specific peptidase 39 (USP39) is generally overexpressed in a variety of cancers, including hepatocellular carcinoma, gastric cancer and so forth. Furthermore, USP39 is proved to be associated with the proliferation of malignant tumors. However, the function and mechanism of USP39 in ovarian cancer have not been elucidated. In the present study, we observed that USP39 was frequently overexpressed in human ovarian cancer and was highly correlated with TNM stage. Suppression of USP39 markedly inhibited the growth and migration of ovarian cancer cell lines HO-8910 and SKOV3 and induced cell cycle G2/M arrest. Moreover, knockdown of USP39 inhibited ovarian tumor growth in a xenograft model. In addition, our findings indicated that cell cycle arrest induced by USP39 knockdown might be involved in p53/p21 signaling pathway. Furthermore, we found that the depletion of USP39 inhibited the migration of ovarian cancer cells via blocking epithelial-mesenchymal transition. Taken together, these results suggest that USP39 may play vital roles in the genesis and progression and may serve as a potential biomarker for diagnosis and therapeutic target of ovarian cancer

Ubiquitin-specific peptidase 39 regulates the process of proliferation and migration of human ovarian cancer via p53/p21 pathway and EMT

Abstract(#br)Ovarian cancer is one of the most lethal gynecological cancers; owning to its late detection and chemoresistance, understanding the pathogenesis of this malignant tumor is much critical. Previous studies have reported that ubiquitin-specific peptidase 39 (USP39) is generally overexpressed in a variety of cancers, including hepatocellular carcinoma, gastric cancer and so forth. Furthermore, USP39 is proved to be associated with the proliferation of malignant tumors. However, the function and mechanism of USP39 in ovarian cancer have not been elucidated. In the present study, we observed that USP39 was frequently overexpressed in human ovarian cancer and was highly correlated with TNM stage. Suppression of USP39 markedly inhibited the growth and migration of ovarian cancer cell..

Optimal convergence rates for semidiscrete finite element approximations of linear space-fractional partial differential equations under minimal regularity assumptions

We consider the optimal convergence rates of the semidiscrete finite element approximations for solving linear space-fractional partial differential equations by using the regularity results for the fractional elliptic problems obtained recently by Jin et al. \cite{jinlazpasrun} and Ervin et al. \cite{ervheuroo}. The error estimates are proved by using two approaches. One approach is to apply the duality argument in Johnson \cite{joh} for the heat equation to consider the error estimates for the linear space-fractional partial differential equations. This argument allows us to obtain the optimal convergence rates under the minimal regularity assumptions for the solution. Another approach is to use the approximate solution operators of the corresponding fractional elliptic problems. This argument can be extended to consider more general linear space-fractional partial differential equations. Numerical examples are given to show that the numerical results are consistent with the theoretical results

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data