Analysis of the Functional Components of Acid Protease and Investigation of Bating Mechanism of Wet-blue

Content: In this study, different acid proteases, which were produced from Aspergillus and Bacillus, were applied for wet-blue bating and their properties and bating effects were observed. The results showed that the acid protease produced Aspergillus had better bating effect and higher chromium tolerance than that of produced by Bacillus. Furthermore, how the acid protease influenced wet-blue microstructure was analyzed by SEM and Micro-CT. The enzymatic properties of acid protease was studied firstly.Zeta potential analysis showed that the isoelectric point (pI) of the protease was consistent with its pH value, which was at 3.0. By particle size analysis, it found that its particle size was 700 nm. In order to obtain the functional components, the molecular weight of the acidic protease was analyzed by Polyacrylamide gel Electrophoresis (SDS-PAGE). Different molecular weight components were obtained by separating the acidic protease with Tangential Flow Filtration (TFF) Technology. The characteristics of these components were determined such as enzyme types and their proportion. Afterwards, these different molecular weight components were used for wet-blue bating. The bating effluent was collected, and then, contents of Hydroxyproline (Hyp), Hyaluronic acid (HA), Desmosine (Des) and Chondroitin sulfate (CS) were analysed, which could be directly corresponding with the degradation of different proteins in wet-blue. Therefore, by characterizing and comparing the bating effect influenced with these different molecular weight components, the functional components of protease could be identified and further be separated and purified. Based on these results, this research is helpful to the development and study of the action of acid protease in the wet-blue bating process. Take-Away: Micro-CT as a new way to characterize the microstructure of leather; Identification and Separation of Effective Components of Acid Protease； Degradation Analysis of Main Components of Wet-Blue during bating process

Chromatin-Based Regulation of Plant Root Development

Plant is endowed with sessile habit and nutrient acquisition mainly through the root organ, which also provides an excellent model to study stem cell fate and asymmetric division due to well-organized cell layers and relatively simple cell types in root meristem. Besides genetic material DNA wrapped around histone octamer, chromatin structure determined by chromatin modification including DNA methylation, histone modification and chromatin remodeling also contributes greatly to the regulation of gene expression. In this review, we summarize the current progresses on the molecular mechanisms of chromatin modification in regulating root development

Effect of physical and chemical pressure on the superconductivity of caged-type quasiskutterudite Lu5Rh6Sn18

Lu5Rh6Sn18 is one of the caged-type quasiskutterudite superconductors with superconducting transition temperature Tc = 4.12 K. Here, we investigate the effect of pressure on the superconductivity in Lu5Rh6Sn18 by combining high pressure electrical transport, synchrotron x-ray diffraction (XRD) and chemical doping. Application of high pressure can enhance both the metallicity and the superconducting transition temperature in Lu5Rh6Sn18. Tc is found to show a continuous increase reaching up to 5.50 K at 11.4 GPa. Our high pressure synchrotron XRD measurements demonstrate the stability of the pristine crystal structure up to 12.0 GPa. In contrast, Tc is suppressed after the substitution of La ions in Lu sites, inducing negative chemical pressure. Our study provides valuable insights into the improvement of superconductivity in caged compounds.Comment: 9 pages, 8 figure

Simultaneous Ship Detection and Orientation Estimation in SAR Images Based on Attention Module and Angle Regression

Ship detection and angle estimation in SAR images play an important role in marine surveillance. Previous works have detected ships first and estimated their orientations second. This is time-consuming and tedious. In order to solve the problems above, we attempt to combine these two tasks using a convolutional neural network so that ships may be detected and their orientations estimated simultaneously. The proposed method is based on the original SSD (Single Shot Detector), but using a rotatable bounding box. This method can learn and predict the class, location, and angle information of ships using only one forward computation. The generated oriented bounding box is much tighter than the traditional bounding box and is robust to background disturbances. We develop a semantic aggregation method which fuses features in a top-down way. This method can provide abundant location and semantic information, which is helpful for classification and location. We adopt the attention module for the six prediction layers. It can adaptively select meaningful features and neglect weak ones. This is helpful for detecting small ships. Multi-orientation anchors are designed with different sizes, aspect ratios, and orientations. These can consider both speed and accuracy. Angular regression is embedded into the existing bounding box regression module, and thus the angle prediction is output with the position and score, without requiring too many extra computations. The loss function with angular regression is used for optimizing the model. AAP (average angle precision) is used for evaluating the performance. The experiments on the dataset demonstrate the effectiveness of our method

High Efficiency Green Phosphor Ba9Lu2Si6O24:Tb3+: Visible Quantum Cutting via Cross-Relaxation Energy Transfers

Tb3+-doped phosphors are widely used in fluorescent lamps and plasma display panels (PDP) due to the strong vacuum ultraviolet (VUV)/UV light absorption of Tb3+. Most of these phosphors are fluorides. The quantum efficiency (QE) of these phosphors is more than 90%; however, it is still too low. Theoretically, one VUV/UV photon can convert two visible photons or more by visible quantum cutting (QC), and the QE can reach 200% or more. Usually, the oxides have a higher QE than fluorides. In this work, we obtained a novel oxide phosphor Ba9Lu2Si6O24:Tb3+ (BLS:Tb3+). Under the 251 nm UV-light excitation, QC processes occur in BLS:Tb3+ via cross-relaxation energy transfers (CRET) between Tb3+ ions, leading to intense green emissions around 552 nm. Based on an indirect method, the ideal QE is calculated nearly to be 171%. When the UV light absorption and energy losses are considered, the practical QE is near 144% estimated by a direct method. This value is much higher than that of the commercial phosphors of 90%, indicating the promising application of BLS:Tb3+ for fluorescent lamps and PDP. The CRET processes were investigated according to the luminescence spectra and decay curves