Spin-flip reflection at the normal metal-spin superconductor interface

We study spin transport through a normal metal-spin superconductor junction. A spin-flip reflection is demonstrated at the interface, where a spin-up electron incident from the normal metal can be reflected as a spin-down electron and the spin $2\times \hbar/2$ will be injected into the spin superconductor. When the (spin) voltage is smaller than the gap of the spin superconductor, the spin-flip reflection determines the transport properties of the junction. We consider both graphene-based (linear-dispersion-relation) and quadratic-dispersion-relation normal metal-spin superconductor junctions in detail. For the two-dimensional graphene-based junction, the spin-flip reflected electron can be along the specular direction (retro-direction) when the incident and reflected electron locates in the same band (different bands). A perfect spin-flip reflection can occur when the incident electron is normal to the interface, and the reflection coefficient is slightly suppressed for the oblique incident case. As a comparison, for the one-dimensional quadratic-dispersion-relation junction, the spin-flip reflection coefficient can reach 1 at certain incident energies. In addition, both the charge current and the spin current under a charge (spin) voltage are studied. The spin conductance is proportional to the spin-flip reflection coefficient when the spin voltage is less than the gap of the spin superconductor. These results will help us get a better understanding of spin transport through the normal metal-spin superconductor junction.Comment: 11 pages, 9 figure

An almond-based low carbohydrate diet improves depression and glycometabolism in patients with Type 2 Diabetes through modulating gut microbiota and GLP-1: A randomized controlled trial

A low carbohydrate diet (LCD) is more beneficial for the glycometabolism in type 2 diabetes (T2DM) and may be effective in reducing depression. Almond, which is a common nut, has been shown to effectively improve hyperglycemia and depression symptoms. This study aimed to determine the effect of an almond-based LCD (a-LCD) on depression and glycometabolism, as well as gut microbiota and fasting glucagon-like peptide 1 (GLP-1) in patients with T2DM. Methods: This was a randomized controlled trial which compared an a-LCD with a low-fat diet (LFD). Forty-five participants with T2DM at a diabetes club and the Endocrine Division of the First and Second Affiliated Hospital of Soochow University between December 2018 to December 2019 completed each dietary intervention for 3 months, including 22 in the a-LCD group and 23 in the LFD group. The indicators for depression and biochemical indicators including glycosylated hemoglobin (HbA1c), gut microbiota, and GLP-1 concentration were assessed at the baseline and third month and compared between the two groups. Results: A-LCD significantly improved depression and HbA1c (p <0.01). Meanwhile, a-LCD significantly increased the short chain fatty acid (SCFAs)-producing bacteria Roseburia, Ruminococcus and Eubacterium. The GLP-1 concentration in the a-LCD group was higher than that in the LFD group (p <0.05). Conclusions: A-LCD could exert a beneficial effect on depression and glycometabolism in patients with T2DM. We speculate that the role of a-LCD in improving depression in patients with T2DM may be associated with it stimulating the growth of SCFAs-producing bacteria, increasing SCFAs production and GPR43 activation, and further maintaining GLP-1 secretion. In future studies, the SCFAs and GPR43 activation should be further examined

Hot Water Extraction of Corn Stover: Hemicellulose Fractionation and its Effect on Subsequent Soda-AQ Pulping

Fractionation of lignocellulosic biomass is an important process in producing biofuels. In this study, hot water extraction of corn stover hemicellulose was carried out at 150, 160, and 170 °C. Variations of sugar content in the hydrolysate under different holding time were detected. The contents of furfural and 5-hydroxymethyl-2-furaldehyde generated during the extraction were also determined. Results showed that the main composition of the hydrolysate was xylo-oligosaccharide; the yield of oligosaccharides first increased as holding time was prolonged. After extraction at 160 °C for 210 min, 70.2% of the total xylan was dissolved, with the generation of furfural (0.90 g/L) and 5-hydroxymethyl-2-furaldehyde (0.10 g/L). The effects of extraction on alkali pulping and bleaching were also investigated. Results indicated that soda-AQ pulp obtained from the extracted material had poorer tensile and burst strengths but better tear strength

Attention Based Spatial-Temporal Graph Convolutional Networks for Traffic Flow Forecasting

Forecasting the traffic flows is a critical issue for researchers and practitioners in the field of transportation. However, it is very challenging since the traffic flows usually show high nonlinearities and complex patterns. Most existing traffic flow prediction methods, lacking abilities of modeling the dynamic spatial-temporal correlations of traffic data, thus cannot yield satisfactory prediction results. In this paper, we propose a novel attention based spatial-temporal graph convolutional network (ASTGCN) model to solve traffic flow forecasting problem. ASTGCN mainly consists of three independent components to respectively model three temporal properties of traffic flows, i.e., recent, daily-periodic and weekly-periodic dependencies. More specifically, each component contains two major parts: 1) the spatial-temporal attention mechanism to effectively capture the dynamic spatialtemporal correlations in traffic data; 2) the spatial-temporal convolution which simultaneously employs graph convolutions to capture the spatial patterns and common standard convolutions to describe the temporal features. The output of the three components are weighted fused to generate the final prediction results. Experiments on two real-world datasets from the Caltrans Performance Measurement System (PeMS) demonstrate that the proposed ASTGCN model outperforms the state-of-the-art baselines

Strategy to Prepare Core–Shell Microspheres for Laser Direct Writing on Polymers: Microemulsion Method

In this study, new core–shell microspheres for polymer laser direct writing (LDW) were successfully designed and prepared by a facile one-step microemulsion method. The color-changing core–shell microsphere consists of a SnO2 “core” which can absorb near-infrared (NIR) laser energy and a polyphenylene oxide (PPO) “shell” which can be easily carbonized at high temperatures. Owing to the unique core–shell structure, the SnO2@PPO microsphere remarkably enhanced the polymer LDW performance. SEM, TEM, and EDS indicated microspheres were regular spheres with an average size of 15.1 μm. Raman spectroscopy and XPS revealed that the SnO2 absorbed NIR laser energy to cause instantaneous high temperatures, leading to the carbonizing of the PPO shell. Thus, the color-change mechanism of the polymer during NIR LDW was confirmed as the formation of amorphous carbon by high-temperature carbonization. We believe these novel microspheres will have wide applications in the field of polymer LDW. Besides, the concept of preparing core–shell microspheres by the one-step microemulsion method provides a new idea for designing color-changing microspheres

Strategy to Prepare Core–Shell Microspheres for Laser Direct Writing on Polymers: Microemulsion Method

In this study, new core–shell microspheres for polymer laser direct writing (LDW) were successfully designed and prepared by a facile one-step microemulsion method. The color-changing core–shell microsphere consists of a SnO2 “core” which can absorb near-infrared (NIR) laser energy and a polyphenylene oxide (PPO) “shell” which can be easily carbonized at high temperatures. Owing to the unique core–shell structure, the SnO2@PPO microsphere remarkably enhanced the polymer LDW performance. SEM, TEM, and EDS indicated microspheres were regular spheres with an average size of 15.1 μm. Raman spectroscopy and XPS revealed that the SnO2 absorbed NIR laser energy to cause instantaneous high temperatures, leading to the carbonizing of the PPO shell. Thus, the color-change mechanism of the polymer during NIR LDW was confirmed as the formation of amorphous carbon by high-temperature carbonization. We believe these novel microspheres will have wide applications in the field of polymer LDW. Besides, the concept of preparing core–shell microspheres by the one-step microemulsion method provides a new idea for designing color-changing microspheres

Strategy to Prepare Core–Shell Microspheres for Laser Direct Writing on Polymers: Microemulsion Method

In this study, new core–shell microspheres for polymer laser direct writing (LDW) were successfully designed and prepared by a facile one-step microemulsion method. The color-changing core–shell microsphere consists of a SnO2 “core” which can absorb near-infrared (NIR) laser energy and a polyphenylene oxide (PPO) “shell” which can be easily carbonized at high temperatures. Owing to the unique core–shell structure, the SnO2@PPO microsphere remarkably enhanced the polymer LDW performance. SEM, TEM, and EDS indicated microspheres were regular spheres with an average size of 15.1 μm. Raman spectroscopy and XPS revealed that the SnO2 absorbed NIR laser energy to cause instantaneous high temperatures, leading to the carbonizing of the PPO shell. Thus, the color-change mechanism of the polymer during NIR LDW was confirmed as the formation of amorphous carbon by high-temperature carbonization. We believe these novel microspheres will have wide applications in the field of polymer LDW. Besides, the concept of preparing core–shell microspheres by the one-step microemulsion method provides a new idea for designing color-changing microspheres

Strategy to Prepare Core–Shell Microspheres for Laser Direct Writing on Polymers: Microemulsion Method

In this study, new core–shell microspheres for polymer laser direct writing (LDW) were successfully designed and prepared by a facile one-step microemulsion method. The color-changing core–shell microsphere consists of a SnO2 “core” which can absorb near-infrared (NIR) laser energy and a polyphenylene oxide (PPO) “shell” which can be easily carbonized at high temperatures. Owing to the unique core–shell structure, the SnO2@PPO microsphere remarkably enhanced the polymer LDW performance. SEM, TEM, and EDS indicated microspheres were regular spheres with an average size of 15.1 μm. Raman spectroscopy and XPS revealed that the SnO2 absorbed NIR laser energy to cause instantaneous high temperatures, leading to the carbonizing of the PPO shell. Thus, the color-change mechanism of the polymer during NIR LDW was confirmed as the formation of amorphous carbon by high-temperature carbonization. We believe these novel microspheres will have wide applications in the field of polymer LDW. Besides, the concept of preparing core–shell microspheres by the one-step microemulsion method provides a new idea for designing color-changing microspheres

Bioresponsive Materials for Drug Delivery Based on Carboxymethyl Chitosan/Poly(γ-Glutamic Acid) Composite Microparticles

Carboxymethyl chitosan (CMCS) microparticles are a potential candidate for hemostatic wound dressing. However, its low swelling property limits its hemostatic performance. Poly(γ-glutamic acid) (PGA) is a natural polymer with excellent hydrophilicity. In the current study, a novel CMCS/PGA composite microparticles with a dual-network structure was prepared by the emulsification/internal gelation method. The structure and thermal stability of the composite were determined by Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). The effects of preparation conditions on the swelling behavior of the composite were investigated. The results indicate that the swelling property of CMCS/PGA composite microparticles is pH sensitive. Levofloxacin (LFX) was immobilized in the composite microparticles as a model drug to evaluate the drug delivery performance of the composite. The release kinetics of LFX from the composite microparticles with different structures was determined. The results suggest that the CMCS/PGA composite microparticles are an excellent candidate carrier for drug delivery