175 research outputs found
First-principles Study of High-Pressure Phase Stability and Superconductivity of Bi4I4
Bismuth iodide Bi4I4 exhibits intricate crystal structures and topological insulating states that are highly susceptible to influence by environments, making its physical properties highly tunable by external conditions. In this work, we study the evolution of structural and electronic properties of Bi4I4 at high pressure using an advanced structure search method in conjunction with first-principles calculations. Our results indicate that the most stable ambient-pressure monoclinic α−Bi4I4 phase in C2/m symmetry transforms to a trigonal P31c structure (ɛ−Bi4I4) at 8.4 GPa, then to a tetragonal P4/mmm structure (ζ−Bi4I4) above 16.6 GPa. In contrast to the semiconducting nature of ambient-pressure Bi4I4, the two high-pressure phases are metallic, in agreement with reported electrical measurements. The ɛ−Bi4I4 phase exhibits distinct ionic states of Iδ− and (Bi4I3)δ + (δ=0.4123 e), driven by a pressure-induced volume reduction. We show that both ɛ- and ζ−Bi4I4 are superconductors, and the emergence of pressure-induced superconductivity might be intimately linked to the underlying structural phase transitions
Electro-fenton reaction by porous carbon based electrocatalysts for water and wastewater treatment
Graph Dynamical Networks for Unsupervised Learning of Atomic Scale Dynamics in Materials
Understanding the dynamical processes that govern the performance of
functional materials is essential for the design of next generation materials
to tackle global energy and environmental challenges. Many of these processes
involve the dynamics of individual atoms or small molecules in condensed
phases, e.g. lithium ions in electrolytes, water molecules in membranes, molten
atoms at interfaces, etc., which are difficult to understand due to the
complexity of local environments. In this work, we develop graph dynamical
networks, an unsupervised learning approach for understanding atomic scale
dynamics in arbitrary phases and environments from molecular dynamics
simulations. We show that important dynamical information can be learned for
various multi-component amorphous material systems, which is difficult to
obtain otherwise. With the large amounts of molecular dynamics data generated
everyday in nearly every aspect of materials design, this approach provides a
broadly useful, automated tool to understand atomic scale dynamics in material
systems.Comment: 25 + 7 pages, 5 + 3 figure
Prediction of fully metallic {\sigma}-bonded boron framework induced high superconductivity above 100 K in thermodynamically stable Sr2B5 at 40 GPa
Metal borides have been considered as potential high-temperature
superconductors since the discovery of record-holding 39 K superconductivity in
bulk MgB2. In this work, we identified a superconducting yet thermodynamically
stable F43m Sr2B5 at 40 GPa with a unique covalent sp3-hybridized boron
framework through extensive first-principles structure searches. Remarkably,
solving the anisotropic Migdal-Eliashberg equations resulted in a high
superconducting critical temperature (Tc) around 100 K, exceeding the boiling
point (77 K) of liquid nitrogen. Our in-depth analysis revealed that the
high-temperature superconductivity mainly originates from the strong coupling
between the metalized {\sigma}-bonded electronic bands and E phonon modes of
boron atoms. Moreover, anharmonic phonon simulations suggest that F43m Sr2B5
might be recovered to ambient pressure. Our current findings provide a
prototype structure with a full {\sigma}-bonded boron framework for the design
of high-Tc superconducting borides that may expand to a broader variety of
lightweight compounds.Comment: 5 page
Exploring the potential mechanisms of Tongmai Jiangtang capsules in treating diabetic nephropathy through multi-dimensional data
BackgroundDiabetic nephropathy (DN) is a prevalent and debilitating disease that represents the leading cause of chronic kidney disease which imposes public health challenges Tongmai Jiangtang capsule (TMJT) is commonly used for the treatment of DN, albeit its underlying mechanisms of action are still elusive.MethodsThis study retrieved databases to identify the components and collect the targets of TMJT and DN. Target networks were constructed to screen the core components and targets. Samples from the GEO database were utilized to perform analyses of targets and immune cells and obtain significantly differentially expressed core genes (SDECGs). We also selected a machine learning model to screen the feature genes and construct a nomogram. Furthermore, molecular docking, another GEO dataset, and Mendelian randomization (MR) were utilized for preliminary validation. We subsequently clustered the samples based on SDECG expression and consensus clustering and performed analyses between the clusters. Finally, we scored the SDECG score and analyzed the differences between clusters.ResultsThis study identified 13 SDECGs between DN and normal groups which positively regulated immune cells. We also identified five feature genes (CD40LG, EP300, IL1B, GAPDH, and EGF) which were used to construct a nomogram. MR analysis indicated a causal link between elevated IL1B levels and an increased risk of DN. Clustering analysis divided DN samples into four groups, among which, C1 and CI were mainly highly expressed and most immune cells were up-regulated. C2 and CII were the opposite. Finally, we found significant differences in SDECG scores between C1 and C2, CI and CII, respectively.ConclusionTMJT may alleviate DN via core components (e.g. Denudatin B, hancinol, hirudinoidine A) targeting SDECGs (e.g. SRC, EGF, GAPDH), with the involvement of feature genes and modulation of immune and inflammation-related pathways. These findings have potential implications for clinical practice and future investigations
The efficacy and safety of Xueshuantong (lyophilized) for injection in the treatment of unstable angina pectoris: A systematic review and meta-analysis
Objective: Xueshuantong (lyophilized) for injection (XST) is an effective botanical drug for treating unstable angina pectoris (UAP). However, a meta-analysis of XST combined with conventional treatment (CT) against UAP has not been conducted. Therefore, this study aimed to investigate the effectiveness and safety of XST combined with CT for UAP patients compared to CT alone.Methods: Randomized controlled trials (RCT) of XST in UAP patients were retrieved from the Cochrane Library, PubMed, Web of Science, EMBASE, CNKI, VIP, Wanfang, and Chinese Biological Medicine Database databases. A meta-analysis was performed using Revman 5.4 and Stata 16.0, and the quality of the included literature was evaluated based on the Cochrane risk-of-bias 2.0 (RoB2.0) tool. The aggregate 95% confidence intervals (CIs), mean difference (MD), and relative risk (RR) estimates were calculated. A GRADE assessment was performed using GRADEprofiler 3.6, and trial sequent analysis was performed using TSA 0.9.Results: Thirty-four studies involving 3,518 patients were included in the analysis. The combination of CT with XST improved the comprehensive clinical efficacy (RR = 1.22, 95% CI: 1.18–1.26, p < 0.00001) and ECG improvement (RR = 1.24, 95% CI: 1.18–1.31, p < 0.00001). The frequency of angina attacks was lower (MD = −0.73, 95% CI: −0.92 to −0.55, p < 0.00001), and the duration was shorter (MD = −1.08, 95% CI: −1.44 to −0.72, p < 0.00001) in the group that received CT combined with XST compared to the one without XST. Total cholesterol levels (MD = −1.30, 95% CI: −1.83 to −0.78, p < 0.00001) and triglyceride levels (MD = −0.76, 95% CI: −0.93 to −0.59, p < 0.00001) were lower in patients who received CT in combination with XST than those who received CT alone. CT combined with XST reduced whole blood viscosity (MD = −0.72, 95% CI = −0.99 to −0.44, p < 0.00001) and plasma viscosity (MD = −0.24, 95% CI: −0.46 to −0.03, p = 0.03). There was no statistically significant difference in the incidence of cardiovascular events or adverse events among patients treated with the combination of XST and CT compared to CT alone. The GRADE assessment indicated that the composite quality of the evidence was low. The trial sequent analysis showed an adequate sample size and stable findings for the clinical efficacy of CT combined with XST for unstable angina.Conclusion: The present systematic review and meta-analysis conditionally indicate that XST combined with CT improved the clinical outcomes of patients with unstable angina more than CT alone with a better safety profile. However, the results need further validation due to limitations in the quality of the included studies.Systematic Review Registration:https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022357395
Conservation and diversification of the miR166 family in soybean and potential roles of newly identified miR166s
Identity between pre-miR166s in soybean. (TIF 5906 kb
Structure and Wear Properties of Nano-silicon dioxide modified Polyacrylate composites
Conference Name:2nd International Conference on Multi-Functional Materials and Structures. Conference Address: Qingdao, PEOPLES R CHINA. Time:OCT 09-12, 2009.polyacrylate/nano-silicon dioxide nanocomposites were fabricated through a simple mixing process for resisting scratch and wear as coating. Chemical compatibility between polyacrylate matrix and nano-silicon dioxide (nano-SiO(2)) was achieved by functionalized nano-SiO(2) via three silane coupling agents. Scanning electron microscopy (SEM) was done to characterize surface and wear morphology of the nanocomposites. Differential scanning calorimetry (DSC) was used for representing interfacial properties of the nanocomposites. A MM-200 machine and a Norman Tool RCA abrader were performed for testing friction and wear properties. SEM showed that incorporation of the nano-SiO(2) functionalized with silane into the polyacrylate matrix showed a better dispersion than the composite without silane at low nanoparticle content (<= 3 wt%). SEM also revealed that adhesive wear mechanism of the polyacrylate matrix was transited to dominated particle wear of the nanocomposites. An increase of glass transition temperature (T(g)) was recorded via DSC at low nanoparticle content (1 wt%). Further addition of the nanoparticles to 3 wt% led to a 10 C increase in T(g) comparing to neat polyacrylate. Results of friction and wear properties exhibited that friction coefficient and wear loss of the nanocomposites with silane were lower than those of the neat polyacrylate. The wear loss of the neat polyacrylate, the nanocomposite containing 3 wt% nanoparticles with silane KH570, and the nanocomposite with raw nano-particles were 108.6, 65.8, and 110.5mg, respectively. RCA results also showed a significant improvement of the nanocomposites in the presence of the nanoparticles with silane
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