[Ginsenoside Re regulates mitochondrial biogenesis through Nrf2/HO-1/PGC-1α pathway to reduce hypoxia/reoxygenation injury in H9c2 cells].

This article explored the mechanism by which ginsenoside Re reduces hypoxia/reoxygenation(H/R) injury in H9c2 cells by regulating mitochondrial biogenesis through nuclear factor E2-related factor 2(Nrf2)/heme oxygenase-1(HO-1)/peroxisome prolife-rator-activated receptor gamma coactivator-1α(PGC-1α) pathway. In this study, H9c2 cells were cultured in hypoxia for 4 hours and then reoxygenated for 2 hours to construct a cardiomyocyte H/R injury model. After ginsenoside Re pre-administration intervention, cell activity, superoxide dismutase(SOD) activity, malondialdehyde(MDA) content, intracellular reactive oxygen species(Cyto-ROS), and intramitochondrial reactive oxygen species(Mito-ROS) levels were detected to evaluate the protective effect of ginsenoside Re on H/R injury of H9c2 cells by resisting oxidative stress. Secondly, fluorescent probes were used to detect changes in mitochondrial membrane potential(ΔΨ_m) and mitochondrial membrane permeability open pore(mPTP), and immunofluorescence was used to detect the expression level of TOM20 to study the protective effect of ginsenoside Re on mitochondria. Western blot was further used to detect the protein expression levels of caspase-3, cleaved caspase-3, Cyto C, Nrf2, HO-1, and PGC-1α to explore the specific mechanism by which ginsenoside Re protected mitochondria against oxidative stress and reduced H/R injury. Compared with the model group, ginse-noside Re effectively reduced the H/R injury oxidative stress response of H9c2 cells, increased SOD activity, reduced MDA content, and decreased Cyto-ROS and Mito-ROS levels in cells. Ginsenoside Re showed a good protective effect on mitochondria by increasing ΔΨ_m, reducing mPTP, and increasing TOM20 expression. Further studies showed that ginsenoside Re promoted the expression of Nrf2, HO-1, and PGC-1α proteins, and reduced the activation of the apoptosis-related regulatory factor caspase-3 to cleaved caspase-3 and the expression of Cyto C protein. In summary, ginsenoside Re can significantly reduce I/R injury in H9c2 cells. The specific mechanism is related to the promotion of mitochondrial biogenesis through the Nrf2/HO-1/PGC-1α pathway, thereby increasing the number of mitochondria, improving mitochondrial function, enhancing the ability of cells to resist oxidative stress, and alleviating cell apoptosis.

[Tetrahydropalmatine inhibiting mitophagy through ULK1/FUNDC1 pathway to alleviate hypoxia/reoxygenation injury in H9c2 cells].

This study explored the specific mechanism by which tetrahydropalmatine(THP) inhibited mitophagy through the UNC-51-like kinase 1(ULK1)/FUN14 domain containing 1(FUNDC1) pathway to reduce hypoxia/reoxygenation(H/R) injury in H9c2 cells. This study used H9c2 cells as the research object to construct a cardiomyocyte H/R injury model. First, a cell viability detection kit was used to detect cell viability, and a micro-method was used to detect lactate dehydrogenase(LDH) leakage to evaluate the protective effect of THP on H/R injury of H9c2 cells. In order to evaluate the protective effect of THP on mitochondria, the chemical fluorescence method was used to detect intracellular reactive oxygen species, intramitochondrial reactive oxygen species, mitochondrial membrane potential, and autophagosomes, and the luciferin method was used to detect intracellular adenosine 5'-triphosphate(ATP) content. Western blot was further used to detect the ratio of microtubule-associated protein 1 light chain 3(LC3) membrane type(LC3-Ⅱ) and slurry type(LC3-Ⅰ) and activated cleaved caspase-3 expression level. In addition, ULK1 expression level and its phosphorylation degree at Ser555 site, as well as the FUNDC1 expression level and its phosphorylation degree of Ser17 site were detected to explore its specific mechanism. The results showed that THP effectively reduced mitochondrial damage in H9c2 cells after H/R. THP protected mitochondria by reducing the level of reactive oxygen species in cells and mitochondria, increasing mitochondrial membrane potential, thereby increasing cellular ATP production, enhancing cellular activity, reducing cellular LDH leakage, and finally alleviating H/R damage in H9c2 cells. Further studies have found that THP could reduce the production of autophagosomes, reduce the LC3-Ⅱ/LC3-Ⅰ ratio, and lower the expression of the apoptosis-related protein, namely cleaved caspase-3, indicating that THP could reduce apoptosis by inhibiting autophagy. In-depth studies have found that THP could inhibit the activation of the ULK1/FUNDC1 pathway of mitophagy and the occurrence of mitophagy by reducing the phosphorylation degree of ULK1 at Ser555 and FUNDC1 at Ser17. The application of ULK1 agonist BL-918 reversely verified the effect of THP on reducing the phosphorylation of ULK1 and FUNDC1. In summary, THP inhibited mitophagy through the ULK1/FUNDC1 pathway to reduce H/R injury in H9c2 cells.

Hydroxysafflor Yellow A Inhibits Pyroptosis and Protecting HUVECs from OGD/R via NLRP3/Caspase-1/GSDMD Pathway.

OBJECTIVE: To observe the protective effect and mechanism of hydroxyl safflower yellow A (HSYA) from myocardial ischemia-reperfusion injury on human umbilical vein endothelial cells (HUVECs). METHODS: HUVECs were treated with oxygen-glucose deprivation reperfusion (OGD/R) to simulate the ischemia reperfusion model, and cell counting kit-8 was used to detect the protective effect of different concentrations (1.25-160 µ mol/L) of HSYA on HUVECs after OGD/R. HSYA 80 µ mol/L was used for follow-up experiments. The contents of inflammatory cytokines interleukin (IL)-18, IL-1 ß, monocyte chemotactic protein 1 (MCP-1), tumor necrosis factor α (TNF-α) and IL-6 before and after administration were measured by enzyme-linked immunosorbent assay. The protein expressions of toll-like receptor, NOD-like receptor containing pyrin domain 3 (NLRP3), gasdermin D (GSDMD) and GSDMD-N-terminal domain (GSDMD-N) before and after administration were detected by Western blot. NLRP3 inflammasome inhibitor cytokine release inhibitory drug 3 sodium salt (CRID3 sodium salt, also known as MCC950) and agonist were added, and the changes of NLRP3, cysteine-aspartic acid protease 1 (Caspase-1), GSDMD and GSDMD-N protein expressions were detected by Western blot. RESULTS: HSYA inhibited OGD/R-induced inflammation and significantly decreased the contents of inflammatory cytokines IL-18, IL-1 ß, MCP-1, TNF-α and IL-6 (P<0.01 or P<0.05). At the same time, by inhibiting NLRP3/Caspase-1/GSDMD pathway, HSYA can reduce the occurrence of pyroptosis after OGD/R and reduce the expression of NLRP3, Caspase-1, GSDMD and GSDMD-N proteins (P<0.01). CONCLUSIONS: The protective effect of HSYA on HUVECs after OGD/R is related to down-regulating the expression of NLRP3 inflammasome and inhibiting pyroptosis.

[Mechanism of Buyang Huanwu Decoction in protecting ischemic myocardium by regulating platelet autophagy in rats with acute myocardial infarction].

This study explored the effects of Buyang Huanwu Decoction(BYHWD) on platelet activation and differential gene expression after acute myocardial infarction(AMI). SD rats were randomly divided into a sham-operated group, a model group, a positive drug(aspirin) group, and a BYHWD group. Pre-treatment was conducted for 14 days with a daily oral dose of 1.6 g·kg~(-1) BYHWD and 0.1 g·kg~(-1) aspirin. The AMI model was established using the high ligation of the left anterior descending coronary artery method. The detection indicators included myocardial infarct size, heart function, myocardial tissue pathology, peripheral blood flow perfusion, platelet aggregation rate, platelet membrane glycoprotein CD62p expression, platelet transcriptomics, and differential gene expression. The results showed that compared with the sham-operated group, the model group showed reduced ejection fraction and cardiac output, decreased peripheral blood flow, and increased platelet aggregation rate and CD62p expression, and activated platelets. At the same time, TXB_2 content increased and 6-keto-PGF1α content decreased in serum. Compared with the model group, BYHWD increased ejection fraction and cardiac output, improved blood circulation in the foot and tail regions and cardiomyocytes arrangement, reduced myocardial infarct size and inflammatory infiltration, down-regulated platelet aggregation rate and CD62p expression, reduced serum TXB_2 content, and increased 6-keto-PGF1α content. Platelet transcriptome sequencing results revealed that BYHWD regulated mTOR-autophagy pathway-related genes in platelets. The differential gene expression levels were detected using real-time quantitative PCR. BYHWD up-regulated mTOR, down-regulated autophagy-related FUNDC1 and PINK genes, and up-regulated p62 gene expression. The results demonstrated that BYHWD could regulate platelet activation, improve blood circulation, and protect ischemic myocardium in AMI rats, and its mechanism is related to the regulation of the mTOR-autophagy pathway in platelets.

Natalizumab Treatment of Relapsing Remitting Multiple Sclerosis Has No Long-Term Effects on the Proportion of Circulating Regulatory T Cells.

INTRODUCTION: Natalizumab (NTZ), a monoclonal antibody against the integrin α4ß1 (VLA-4) found on activated T cells and B cells, blocks the interaction of this integrin with adhesion molecules of central nervous system (CNS) endothelial cells and lymphocyte migration through the blood-brain barrier, effectively preventing new lesion formation and relapses in multiple sclerosis (MS). Whether NTZ treatment has additional effects on the peripheral immune system cells, and how its actions compare with other MS disease-modifying treatments, have not been extensively investigated. In particular, its effect on the proportions of circulating regulatory T cells (Treg) is unclear. METHODS: In this study, we investigated the effect of NTZ treatment in 12 patients with relapsing MS, at 6 and 12 months after the start of treatment. We evaluated the proportions of regulatory T cells (Treg), defined by flow cytometry as CD4+ CD25++ FoxP3+ cells and CD4+ CD25++ CD127- cells at these intervals. As an exploratory study, we also investigated the NTZ effects on the proportions of bulk T and B lymphocyte populations, and of those expressing novel the markers CD195 (CCR5), CD196 (CCR6), or CD161 (KLRB1), which are involved in MS pathogenesis but have been studied less in the context of MS treatment. The effects of NTZ were compared to those obtained with 11 patients under interferon-beta-1a (IFN-ß1a) treatment, and against 9 healthy volunteers. RESULTS: We observed a transient increment in the proportion of Treg cells at 6 months, which was not sustained at 12 months. We observed a reduction in the proportion of T cells expressing CD195 (CCR5) and CD161 (KLRB1) subsets of T cells. CONCLUSION: We conclude that NTZ does not have an effect on the proportion of Treg cells over 1 year, but it may affect the expression of molecules important for some aspects MS pathogenesis, in a manner that is not shared with IFN-ß1a.

Preparation of water storage ceramsite via dredged silt and biomass waste: Pore formation, water purification and application.

Natural water pollution and eutrophication are environmental problems that urgently need to be solved. Porous ceramsite could be applied for both water storage and water purification. This research used biomass and dredged silt to prepare water storage ceramsite (WSC), and investigated the adsorption and removal effects of WSC on phosphorus (P), nitrogen ((NH4+)N) and chemical oxygen demand (COD). The results showed that the biomass was mostly burned and partially carbonized during the high-temperature sintering process to form a rich pore structure inside the material. The rich pore structure effectively improved the water absorption to 105.58 %. The abundant specific surface area could provide many attachment sites, which is conducive to the adsorption of target ions by WSC. Further testing showed that WSC could adsorb ions with different charges in different pH solutions. Therefore, this study provides a sustainable solution for the co-utilization of biomass waste and dredged silt, and the application of WSC could reduce the damage caused by extreme rainfall and water pollution.

[Effect of Jinzhen Oral Liquid on cough after lipopolysaccharide-induced infection in rats and mechanism].

This study aims to explore the effect of Jinzhen Oral Liquid(JOL) on cough after infection in rats and the mechanism. To be specific, a total of 60 male SD rats were classified into 6 groups: normal group(equivalent volume of distilled water, ig), model group(equivalent volume of distilled water, ig), Dextromethorphan Hydrobromide Oral Solution group(3.67 mL·kg~(-1), ig), high-, medium-, and low-dose JOL groups(11.34, 5.67, and 2.84 mL·kg~(-1), respectively, ig). Lipopolysaccharide(LPS, nasal drip), smoking, and capsaicin(nebulization) were employed to induce cough after infection in rats except the normal group. Administration began on the 19 th day and lasted 7 days. Capsaicin(nebulization) was used to stimulate cough 1 h after the last administration and the cough frequency and cough incubation period in rats were recorded. The pathological morphology of lung tissue was observed based on hematoxylin-eosin(HE) staining. Immunohistochemistry(IHC) was used to detect the specific expression of transient receptor potential vanilloid 1(Trpv1), nerve growth factor(NGF), tropomyosin receptor kinase A(TrkA), and phosphorylated-p38 mitogen-activated protein kinase(p-p38 MAPK) in lung tissue, Western blot the protein expression of Trpv1, NGF, TrkA, and p-p38 MAPK in lung tissue, and real-time fluorescent quantitative polymerase chain reaction(real-time PCR) the mRNA expression of Trpv1, NGF, and TrkA. The results showed that model group demonstrated significantly high cough frequency, obvious proliferation and inflammatory cell infiltration in lung tissue, significantly enhanced positive protein expression of Trpv1, NGF, TrkA, and p-p38 MAPK in lung tissue and significant increase in the mRNA expression of Trpv1, NGF, and TrkA compared with the normal group. Compared with the model group, JOL can significantly reduce the cough frequency, alleviate the pathological changes of lung tissue, and decrease the protein expression of Trpv1, NGF, TrkA, and p-p38 MAPK in lung tissue, and high-dose and medium-dose JOL can significantly lower the mRNA expression of Trpv1, NGF, and TrkA. This study revealed that JOL can effectively inhibit Trpv1 pathway-related proteins and improve cough after infection. The mechanism is that it reduces the expression of NGF, TrkA, and p-p38 MAPK in lung tissue, thereby decreasing the expression of Trpv1 and cough sensitivity.

Abnormally weak intervalley electron scattering in MoS2 monolayer: insights from the matching between electron and phonon bands.

It is known that carrier mobility in layered semiconductors generally increases from two-dimensions (2D) to three-dimensions due to fewer scattering channels resulting from decreased densities of electron and phonon states. In this work, we find an abnormal decrease of electron mobility from monolayer to bulk MoS2. By carefully analyzing the scattering mechanisms, we can attribute such abnormality to the stronger intravalley scattering in the monolayer but weaker intervalley scattering caused by few intervalley scattering channels and weaker corresponding electron-phonon couplings compared to the bulk case. We show that it is the matching between the electronic band structure and phonon spectrum rather than their densities of electronic and phonon states that determines scattering channels. We propose, for the first time, the phonon-energy-resolved matching function to identify the intra- and inter-valley scattering channels. Furthermore, we show that multiple valleys do not necessarily lead to strong intervalley scattering if: (1) the scattering channels, which can be explicitly captured by the distribution of the matching function, are few due to the small matching between the corresponding electron and phonon bands; and/or (2) the multiple valleys are far apart in the reciprocal space and composed of out-of-plane orbitals so that the corresponding electron-phonon coupling strengths are weak. Consequently, the searching scope of high-mobility 2D materials can be reasonably enlarged using the matching function as useful guidance with the help of band edge orbital analysis.

Semiconductor-to-metal transition from monolayer to bilayer blue phosphorous induced by extremely strong interlayer coupling: a first-principles study.

Monolayer blue phosphorous has a large band gap of 2.76 eV but counterintuitively the most stable bilayer blue phosphorous has a negative band gap of -0.51 eV. Such a large band gap reduction from just monolayer to bilayer has not been revealed before, the underlying mechanism behind which is important for understanding interlayer interactions. In this work, we reveal the origin of the semiconductor-to-metal transition using first-principles calculations and tight-binding models. We find that the interlayer interactions are extremely strong, which can be attributed to the short layer distance and strong π-like atomic orbital couplings. Therefore, the upshift of the valence band maximum (VBM) from monolayer to bilayer blue-P is so large that the VBM in the bilayer gets higher than the conduction band minimum, leading to a negative band gap and an energy gain. Besides, the interlayer atomic misplacements weaken the couplings of out-of-plane orbitals. Therefore, the energy gain due to the semiconductor-to-metal transition is larger than the energy cost due to interlayer repulsions, thus stabilizing the metallic phase. The large band gap reduction with layer number increasing is expected to exist in other similar layered systems.

Crystal structure prediction by combining graph network and optimization algorithm.

Crystal structure prediction is a long-standing challenge in condensed matter and chemical science. Here we report a machine-learning approach for crystal structure prediction, in which a graph network (GN) is employed to establish a correlation model between the crystal structure and formation enthalpies at the given database, and an optimization algorithm (OA) is used to accelerate the search for crystal structure with lowest formation enthalpy. The framework of the utilized approach (a database + a GN model + an optimization algorithm) is flexible. We implemented two benchmark databases, i.e., the open quantum materials database (OQMD) and Matbench (MatB), and three OAs, i.e., random searching (RAS), particle-swarm optimization (PSO) and Bayesian optimization (BO), that can predict crystal structures at a given number of atoms in a periodic cell. The comparative studies show that the GN model trained on MatB combined with BO, i.e., GN(MatB)-BO, exhibit the best performance for predicting crystal structures of 29 typical compounds with a computational cost three orders of magnitude less than that required for conventional approaches screening structures through density functional theory calculation. The flexible framework in combination with a materials database, a graph network, and an optimization algorithm may open new avenues for data-driven crystal structural predictions.

Enhancing Hole Density and Suppressing Recombination Centers through Illumination in Kesterite Thin Film Solar Cells.

Enhancing carrier density and increasing carrier lifetime are critical for the good performance of thin film solar cells. We apply illumination during the growth of kesterite Cu2ZnSnS4 (CZTS) to enhance hole density and suppress defects of nonradiative electron-hole recombination centers simultaneously. To examine the effect of the injected carriers generated by illumination, we first extend the scheme of detailed balance equations relating free carriers and defects beyond thermal equilibrium conditions by developing an extended Fermi level (EF') to characterize a homogeneous semiconductor with non-equilibrium carriers. On the basis of this scheme, we find that illumination can promote the formation of carrier-providing defects and suppress the formation of carrier-compensating defects. Then, we demonstrate that applying proper illumination during the growth of CZTS will help achieve a higher hole density and simultaneously suppress the formation of the SnZn antisite significantly, which are beneficial for the performance of CZTS solar cells.

Effective lifetime of non-equilibrium carriers in semiconductors from non-adiabatic molecular dynamics simulations.

The lifetimes of non-equilibrium charge carriers in semiconductors calculated using non-adiabatic molecular dynamics often differ from experimental results by orders of magnitude. By revisiting the definition of carrier lifetime, we report a systematic procedure for calculating the effective carrier lifetime in semiconductor crystals under realistic conditions. The consideration of all recombination mechanisms and the use of appropriate carrier and defect densities are crucial to bridging the gap between modeling and measurements. Our calculated effective carrier lifetime of CH3NH3PbI3 agrees with experiments, and is limited by band-to-band radiative recombination and Shockley-Read-Hall defect-assisted non-radiative recombination, whereas the band-to-band non-radiative recombination is found to be negligible. The procedure is further validated by application to the compound semiconductors CdTe and GaAs, and thus can be applied in carrier lifetime simulations in other material systems.

Effect of omega-3 fatty acids supplementation on indirect blood markers of exercise-induced muscle damage: Systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Omega 3 fatty acids supplementation may have an attenuative effect on exercise-induced muscle damage (EIMD) through the cell membrane stabilization. The purpose of the present meta-analysis was to evaluate the effects of omega 3 fatty acids supplementation, on indirect blood markers of muscle damage following EIMD in trained and untrained individuals. METHODS: Scopus, Medline, and Google scholar systematically searched up to January 2021. The Cochrane Collaboration tool was used for the quality of studies. Random-effects model, weighted mean difference (WMD), and 95% confidence interval (CI) were applied for the overall effect estimating. The heterogeneity between studies was evaluated applying the chi-squared and I2 statistic. RESULTS: The outcomes showed a significant effect of omega 3 supplementation on reducing creatine kinase (CK), lactate dehydrogenase (LDH), and myoglobin (Mb) concentrations. In addition, a subgroup analysis indicated a significant reduction in CK, LDH, and Mb concentrations, based on follow-ups after exercise, studies duration, time of supplementation, and training status. CONCLUSION: The current meta-analysis indicated an efficacy of omega 3 in reducing CK, LDH, and Mb serum concentration among healthy individuals, overall and in subgroups analysis. Thus, omega 3 should be considered as a priority EIMD recovery agent in interventions.

Unusual interlayer coupling in layered Cu-based ternary chalcogenides CuMCh2 (M = Sb, Bi; Ch = S, Se).

Interlayer interactions play important roles in manipulating the electronic properties of layered semiconductors. One common mechanism is that the valence band maximum (VBM) and the conduction band minimum (CBM) in one layer couple to the VBM and CBM in another layer, respectively, resulting in the decrease of the band gap from the monolayer to the bilayer. Here we report an unusual interlayer coupling mechanism in layered Cu-based ternary chalcogenides CuMCh2 (M = Sb, Bi; Ch = S, Se) that the CBM in one layer strongly couples to the VBM in the other layer, leading to the band gap increase from the monolayer to the bilayer. Such an unusual interlayer interaction arises from the entangling between the electronic structures and the structures of CuMCh2 in which the cations M and anions Ch are alternatively arranged at the outmost part of each layer. Consequently, the M atom at the bottom of the upper layer is very close to the Ch atom at the top of the bottom layer, so that the orbitals of the M atom which dominate the CBM can strongly couple to the orbitals of the Ch atom which dominate the VBM, as demonstrated by the orbital hopping integrals obtained from the Wannier function analysis. The exceptional case of the unusual interlayer interaction revealed in this work enriches the diversity of the interlayer interactions in layered materials and is expected to exist in similar layered systems in which cations and anions are alternatively arranged at the outmost part of each layer.

[Network Meta-analysis of clinical efficacy of Chinese herbal injection in adjuvant treatment of unstable angina pectoris].

The present study evaluated the curative efficacy of Chinese herbal injection on unstable angina pectoris( UAP) by network Meta-analysis. The databases,including Pub Med,Cochrane Library,Web of Science,CNKI,CBM,VIP and Wanfang were searched for randomized controlled trial( RCT) of Chinese herbal injection in the treatment of UAP. All researchers independently screened the articles,extracted the data and evaluated the quality. Open BUGS and Stata were employed for the analysis of the trials that met the quality standards. Fifty-eight studies were finally included in this study,involving 20 intervention measures. In terms of the effective rate,16 injections such as Dengzhan Xixin Injection,Xuesaitong Injection and Danshen Injection combined with western medicine exhibited significant efficacy. In terms of ECG,Puerarin Injection,Ginkgo Leaf Extract and Dipyridamole Injection( GDI),Breviscapine Injection combined with western medicine were superior to western medicine. In terms of the reduction of the angina attack times,Sodium Tanshinone ⅡASulfonate Injection,GDI and Dazhu Hongjingtian Injection combined with western medicine showed better effects than western medicine. In terms of shortening the angina duration,Shenmai Injection combined with western medicine was superior to western medicine. As revealed by the results,Dengzhan Xixin Injection,Xuesaitong Injection,Danshen Injection,Breviscapine Injection,Danshen Ligustrazine Injection combined with western medicine displayed prominent curative efficacy,which were recommended for clinical application. Meanwhile,appropriate intervention measures should be selected according to individual conditions. Limited by the quality of the included trials,the conclusions still need to be further verified.

Hyperdynamics simulations with ab initio forces.

By applying the locally optimal rotation method to deal with the lowest eigenvalue of a Hessian matrix, we have efficiently incorporated the hyperdynamics method into the ab initio scheme. In the present method, we only need to calculate the first derivative of the potential and several more force calls in each molecular dynamics (MD) step, which makes hyperdynamics simulation applicable in ab initio MD simulations. With this implementation, we are able to simulate defect diffusion in silicon with boost factors up to 105. We utilized both direct MD and the hyperdynamics method to investigate diffusion of lithium atoms and silicon vacancies in silicon. We identified the complex diffusion process. The obtained diffusion coefficients of Li atoms and Si vacancies are in good agreement with the direct MD results.

Dimensionality-Inhibited Chemical Doping in Two-Dimensional Semiconductors: The Phosphorene and MoS2 from Charge-Correction Method.

Despite the great appeal of two-dimensional semiconductors for electronics and optoelectronics, to achieve the required charge carrier concentrations by means of chemical doping remains a challenge due to large defect ionization energies (IEs). Here, by decomposing the defect IEs into three parts based on ionization process, we propose a conceptual picture that the large defect IEs are caused by two effects of reduced dimensionality. While the quantum confinement effect makes the neutral single-electron point defect levels deep, the reduced screening effect leads to high energy cost for the electronic relaxation. The first-principles calculations for black phosphorus and MoS2 do demonstrate the general trend. Using BP monolayer either embedded into dielectric continuum or encapsulated between two hBN layers, we demonstrate the feasibility of increasing the screening to reduce the defect IEs. Our analysis is expected to help achieve effective carrier doping and open ways toward more extensive applications of 2D semiconductors.

More Se Vacancies in Sb2 Se3 under Se-Rich Conditions: An Abnormal Behavior Induced by Defect-Correlation in Compensated Compound Semiconductors.

It was believed that the Se-rich synthesis condition can suppress the formation of deep-level donor defect VSe (selenium vacancy) in Sb2 Se3 and is thus critical for fabricating high-efficiency Sb2 Se3 solar cells. However, here it is shown that by first-principles calculations the density of VSe increases unexpectedly to 1016 cm-3 when the Se chemical potential increases, so Se-rich condition promotes rather than suppresses the formation of VSe . Therefore, high density of VSe is thermodynamically inevitable, no matter under Se-poor or Se-rich conditions. This abnormal behavior can be explained by a physical concept "defect-correlation", i.e., when donor and acceptor defects compensate each other, all defects become correlated with each other due to the formation energy dependence on Fermi level which is determined by densities of all ionized defects. In quasi-1D Sb2 Se3 , there are many defects and the complicated defect-correlation can give rise to abnormal behaviors, e.g., lowering Fermi level and thus decreasing the formation energy of ionized donor VSe 2+ in Se-rich Sb2 Se3 . Such behavior exists also in Sb2 S3 . It explains the recent experiments that the extremely Se-rich condition causes the efficiency drop of Sb2 Se3 solar cells, and demonstrates that the common chemical intuition and defect engineering strategies may be invalid in compensated semiconductors.

Mechanism of 'Invigorating Qi and Promoting Blood Circulation' Drug Pair Ginseng-Danshen on Treatment of Ischemic Heart Disease Based on Network Pharmacology.

OBJECTIVE: Using network pharmacology to explore the mechanism of the 'invigorating qi and promoting blood circulation' drug pair Ginseng-Danshen (Salvia miltiorrhiza) on treatment of ischemic heart disease (IHD). METHODS: The chemical constituents of ginseng and Danshen drug pair were identified by searching the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP), and the potential targets of the pair were identified. The pharmacodynamics of the pair was analyzed using network pharmacology. The targets of IHD were identified by database screening. Using protein-protein interaction network, the interaction targets of Ginseng-Danshen on IHD were constructed. A "constituent-target-disease" interaction network was constructed using Cytoscape software, Gene Ontology (GO) term enrichment analysis and biological pathway enrichment analysis were carried out, and the mechanism of improving myocardial ischemia by the Ginseng-Danshen drug pair was investigated. RESULTS: Seventeen active constituents and 53 targets were identified from ginseng, 53 active constituents and 61 targets were identified from Danshen, and 32 protein targets were shared by ginseng and Danshen. Twenty GO terms were analyzed, including cytokine receptor binding, cytokine activity, heme binding, and antioxidant activity. Sixty Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathways were analyzed, including phosphatidylinositol 3-kinase-serine-threonine kinase (PI3K-AKT) signaling pathway, p53 signaling pathway, interleukin 17 signaling pathway, tumor necrosis factor signaling pathway, and the advanced glycation end product (AGE)-the receptor for AGE (RAGE) signaling pathway in diabetic complications. CONCLUSION: The specific mechanism of Ginseng-Danshen drug pair in treating IHD may be associated with improving the changes of metabolites inbody, inhibiting the production of peroxides, removing the endogenous oxygen free radicals, regulating the expression of inflammatory factors, reducing myocardial cell apoptosis and promoting vascular regeneration.

Fully Boron-Sheet-Based Field Effect Transistors from First-Principles: Inverse Design of Semiconducting Boron Sheets.

High-performance two-dimensional (2D) field effect transistors (FETs) have a broad application prospect in future electronic devices. The lack of an ideal material system, however, hinders the breakthrough of 2D FETs. Recently, phase engineering offers a promising solution, but it requires both semiconducting and metallic phases of materials. Here we suggest borophenes as ideal systems for 2D FETs by theoretically searching semiconducting phases. Using multiobjective differential optimization algorithms implemented in the IM2ODE package and the first-principles calculations, we have successfully identified 16 new semiconducting borophenes. Among them, the B12-1 borophene is the most stable semiconducting phase, whose total energy is lower than any other known semiconducting borophenes. By considering not only the band alignments but also the lattice matches between semiconducting and metallic borophenes, we then have theoretically proposed several device models of fully boron-sheet-based 2D FETs. Our work provides beneficial ideas and attempts for discovering novel borophene-based 2D FETs.