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Topological Hall effect is an abnormal Hall response arising from the scalar spin chirality of chiral magnetic textures. Up to now, such an effect is only observed in certain special materials, but rarely in traditional ferromagnets. In this work, we have implemented the molecular beam epitaxy technique to successfully embed black-phosphorus-like bismuth nanosheets with strong spin-orbit coupling into the bulk of chromium telluride Cr2Te3, as evidenced by atomically resolved energy dispersive X-ray spectroscopy mapping. Distinctive from pristine Cr2Te3, these Bi-embedded Cr2Te3 epitaxial films exhibit not only pronounced topological Hall effects, but also magnetoresistivity anomalies and differential magnetic susceptibility plateaus. All these experimental features point to the possible emergence of magnetic skyrmions in Bi-embedded Cr2Te3, which is further supported by our numerical simulations with all input parameters obtained from the first-principle calculations. Therefore, our work demonstrates a new efficient way to induce skyrmions in ferromagnets, as well as the topological Hall effect by embedding nanosheets with strong spin-orbit couplings.

Materials that have a perpendicular magnetic anisotropy (PMA) effect with a high Curie temperature are essential in spintronics applications. Cr2Te3 is a transition-metal chalcogenide that demonstr...

During the systematic screening of bioactive compounds from our marine natural product library, crude extract of the marine-derived fungus strain Aspergillus fumigatus MF029 exhibited moderate bioactivities against Bacillus subtilis, Staphylococcus aureus, methicillin-resistant S. aureus, and Mycobacterium bovis bacillus Calmette-Guerin (BCG). Further chemical investigation resulted in the identification of two new compounds, chaetominine A (1) and sphingofungin I (2), together with four known compounds, emodin (3), chaetominine (4), sphingofungin D (5) and trypacidin (6). Trypacidin displayed potential antitubercular activity with MIC value of 1.25 μg/mL.

A new xanthenone derivative, 3-hydroxy pinselin (1), together with five known analogues (2–6) were isolated from the marine-derived fungus Aspergillus versicolor MF160003. Their structures were identified by extensive 1D- and 2D-NMR, and high-resolution mass spectrometry data. Compounds 5 and 6 showed moderate bioactivities against BCG with MIC values of 40 and 20 μg/mL, respectively.

Vascularization is vital for the survival and functionality of complex tissue-engineered organs, and immune microenvironment is pivotal for effective vascularization. 3D bioprinting is a powerful technique for manufacturing engineered tissues. However, the reconstruction of functionalized vascular scaffolds with immunomodulatory properties through 3D bioprinting has rarely been reported. In this study, we fabricated scaffolds with immunomodulatory properties by incorporating INF-γ loaded laponite into the mixtures of gelatin methacrylate (GelMA)/alginate/4-arm poly(ethylene glycol) acrylate (PEG) (GAP) through coaxial bioprinting method with a sequential cross-linking mechanism that allows for stable production of 3D microfibrous scaffolds. Laponite addition optimized the hydrogel's physical and chemical performance, improved the rheological properties and printing feasibility while enhancing mechanical stress, making the direct fabrication of scaffolds with increased porosity and decreased filament diameter possible. Furthermore, new scaffolds facilitated the expression of chemotactic factors and accelerated EPC migration toward the microfiber peripheries to form a layer of confluent endothelium. Meanwhile, the scaffolds were capable of releasing IFN-γ in the early stage to stimulate macrophage M1 polarization, followed by induction of M2 polarization via the release of Si4+, Mg2+ as the degradation of laponite occurred, which successfully improved the sprouting and mature of newly formed vasculature, as well as vascularized bone regeneration. Our results suggested that a combination of GAP-IFN-γ@Lap bioink with a dual-step cross-linking procedure could regulate the local immune microenvironment, aiding the formation of a confluent endothelium, promoting angiogenesis and tissue regeneration, which potentially provides an efficient and simple strategy for developing complex vascularized tissues.

Since the discovery of the first antibiotic, natural products have played an important role in chemistry, biology and medicine. To explore the potential of bioactive compounds from microbes isolated from the southeast of Tibet, China, a crude extract library was constructed and screened against Staphylococcus aureus. The strain Nocardiopsis sp. LS150010 was scaled up and subjected to further chemical studies, resulting in the identification of N-salicyloyl-2-aminopropan-1,3-diol (2) and its rare aziridine derivative, madurastatin B3 (1). Their structures were determined by detailed analysis of 1D, 2D NMR and HRMS data. Compounds 1 and 2 displayed significant inhibitory activity against S. aureus and methicillin resistant S. aureus, with MIC values of 6.25 µg/mL. Compound 1 also showed potent inhibitory activity against Bacillus subtilis and Escherichia coli, as well as activity in a Mycobacterium tuberculosis Bacillus Calmette-Guérin infected THP-1 cell model.

Charge transfer is of particular importance in manipulating the interface physics in transition-metal oxide heterostructures. In this work, we have fabricated epitaxial bilayers composed of polar 3d LaMnO

e15000 Background: To explore the correlation between plasma concentration of apatinib and clinical efficacy. Methods: 42 patients were enrolled. Plasma specimens of all patients were collected. At 7:40 am, fasting blood was drawn as plasma trough concentration (Ctrough). At 8 am, apatinib mesylate (APA-M, 250mg qd) was orally administrated. At 11 am, venous blood was drawn as plasma peak concentration (Cpeak). Each patient has Ctrough and Cpeak samples. A total of 84 plasma samples were obtained. The concentration of APA-M in plasma was determined by UPLC-MS/MS. Results: 1) 42 patients were evaluable. Treatment response was assessed by RECIST1.1. 2 patients achieved complete response (CR), 16 partial response (PR), 12 stable disease (SD) (tumor shrinks), 5 SD (tumor enlargement), 7 progressive disease (PD). Objective response rate (ORR) was 42.9% (18/42) and disease control rate (DCR) was 83.3% (35/42). 2) On day 1 and 456 after oral APA-M from different patients, median trough concentration (Ctrough median) was 264.38 ng/ml (1.18 ng/ml-918 ng/ml), and median peak concentration (Cpeak median) was 543.61 ng/ml (71.11 ng/ml-1609.4 ng/ml), respectively. 3) The Ctrough median in patients with CR, PR and SD (tumor shrinks) was significantly higher than that SD (tumor enlargement) and PD ( P＜0.05). There was significantly difference between CR and PR with SD (tumor shrinks) ( P＜0.05). But there was no significantly difference between CR and PR ( P＞0.05). (Table) 4) The Cpeak median in patients with CR, PR, SD (tumor enlargement) and PD was significantly higher than that SD (tumor shrinks) ( P＜0.05). But there was no significantly difference between CR and PR with SD (tumor enlargement) ( P＞0.05). (Table). Conclusions: The plasma Ctrough of Apatinib can predict the clinical efficacy of patients with solid tumor. Perspective clinical studies with adequate sample size are required to validate our results. [Table: see text]

Drug-induced liver injury (DILI) is a major clinical problem where natural compounds hold promise for its abrogation. Khaya grandifoliola (Meliaceae) is used in Cameroonian traditional medicine for the treatment of liver related diseases and has been studied for its hepatoprotective properties. Till date, reports showing the hepatoprotective molecular mechanism of the plant are lacking. The aim of this study was therefore to identify compounds from the plant bearing hepatoprotective activity and the related molecular mechanism by assessing their effects against acetaminophen (APAP)-induced hepatotoxicity in normal human liver L-02 cells line. The cells were exposed to APAP (10 mM) or co-treated with phytochemical compounds (40 μM) over a period of 36 h and, biochemical and molecular parameters assessed. Three known limonoids namely 17-epi-methyl-6-hydroxylangolensate, 7-deacetoxy-7-oxogedunin and deacetoxy-7R-hydroxygedunin were identified. The results of cells viability and membrane integrity, reactive oxygen species generation and lipid membrane peroxidation assays, cellular glutathione content determination as well as expression of cytochrome P450 2E1 demonstrated the protective action of the limonoids. Immunoblotting analysis revealed that limonoids inhibited APAP-induced c-Jun N-terminal Kinase phosphorylation (p-JNK), mitochondrial translocation of p-JNK and Bcl2-associated X Protein, and the release of Apoptosis-inducing Factor into the cytosol. Interestingly, limonoids increased the expression of Mitogen-activated Protein Kinase Phosphatase (Mkp)-1, an endogenous inhibitor of JNK phosphorylation and, induced the nuclear translocation of Nuclear Factor Erythroid 2-related Factor-2 (Nrf2) and decreased the expression of Kelch-like ECH-associated Protein-1. The limonoids also reversed the APAP-induced decreased mRNA levels of Catalase, Superoxide Dismutase-1, Glutathione-S-Transferase and Methionine Adenosyltransferase-1A. The obtained results suggest that the isolated limonoids protect L-02 hepatocytes against APAP-induced hepatotoxicity mainly through increase expression of Mkp-1 and nuclear translocation of Nrf2. Thus, these compounds are in part responsible of the hepatoprotective activity of K. grandifoliola and further analysis including in vivo and toxicological studies are needed to select the most potent compound that may be useful as therapeutic agents against DILI.

Superconductivity is realized in Fe 1+ x Te ( x =0.1–0.2) thin films grown on topological insulator Bi 2 Te 3 by molecular beam epitaxy. A thorough analysis of the obtained transport data in terms of the vortex glass theory reveals the occurrence of a spontaneous vortex glass phase transition in the superconducting Fe 1+ x Te films. Such a phase transition is ascribed to the presence of excess Fe in Fe 1+ x Te, indicating the important role of excess Fe in the vortex dynamics of iron chalcogenide. Based on the transport data, a phase diagram of Fe 1+ x Te is also constructed.

This study was focused on preparation and characterization of fatty acid eutectic mixtures as phase change materials (PCMs). The four common fatty acids: stearic acid (SA), palmitic acid (PA), myristic acid (MA) and lauric acid (LA) were selected as representative to prepare binary and ternary eutectic mixtures by heating-ultrasonic method. The melting points of LA–MA, LA–SA, SA–MA, SA–PA, MA–PA, LA–MA–SA, MA–SA–PA mixtures with varying combination proportions were determined and then analyzed by drawing the phase diagrams to determine the eutectic points and the corresponding mixing proportions. The results showed that the eutectic temperature of ternary fatty acids was lower than binary fatty acids’; ternary mixture possessed the same thermal properties with pseudo-binary mixture in both melting temperature and latent heat of phase change; the Schroeder-Van Laar equation can be taken as a basis for mixing proportion of pseudo-binary fatty acid and ternary fatty acid systems; the ternary eutectic point on the ternary phase diagram was just in the vicinity of a small triangle which was formed by the connection between the three vertices and the three eutectic points of binary fatty acid in the corresponding across flats. Moreover, ternary and pseudo-binary mixtures had advantage in energy conservation applications such as building heating/cooling and indoor temperature controlling especially when the temperature in need was low.

During the systematic screening of active compounds from marine-derived fungi, the extract of a strain of Aspergillus versicolor MF359 isolated from a marine sponge of Hymeniacidon perleve was identified for detailed chemical investigation. Three new secondary metabolites, named hemiacetal sterigmatocystin (1), acyl-hemiacetal sterigmatocystin (2), and 5-methoxydihydrosterigmatocystin (3), together with a known compound, aversin (4), were characterized. 1 represents a first structure of sterigmatocystin hemiacetal from nature. The antibacterial activities of these identified compounds were evaluated against Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, Bacillus subtilis, and Pseudomonas aeruginosa. Compound 3 showed activity against S. aureus and B. subtilis with MIC values of 12.5 and 3.125 μg/mL, respectively.

This work was focused on investigating the effects of compounding conditions on the properties of fatty acids eutectic mixtures as phase change materials (PCMs), and the binary eutectic mixtures of stearic acid (SA) and myristic acid (MA) were selected as representative. The melting points of SA–MA mixtures with varying combination proportions were tested to determine eutectic ratio. Adopting heating-ultrasonic method, the SA–MA mixtures with eutectic ratio were blended under different conditions to obtain a series of eutectic mixtures, and then their thermal properties and chemical structures were analyzed by differential scanning calorimetry (DSC) and Fourier transform infrared (FT-IR), respectively. The results showed that the eutectic mass ratio of SA to MA was 36–64%; within certain time range, more heating time can result in lower melting point, but not the longer, the better; when the heating temperature increased, the melting point of eutectic mixture had a little irregular change, but the melting time of solid mixture obviously reduced, so, heating temperature should be considered synthetically to save energy; ultrasonic vibrating process hardly had influences on the properties of eutectic mixtures, and can be canceled; the preparation of fatty acids eutectic mixture did not have any damages to the chemical structures of fatty acids.

Red mud (RM) by-product of Bayer process was added to clay in different proportions to prepare ceramic bodies and the physical properties of the clay ceramic bodies, bulk density, loss on ignition, sintering shrinkage, water absorption and compressive strength were determined. The optimum preparation condition was determined, and the corresponding influence mechanisms were discussed. Due to the high alkalinity and water absorption, RM obviously influenced the properties of clay ceramic bodies, and the optimum parameters were selected as firing temperature of 1050 °C, firing time of 2 h and RM content of 20%. During sintering some components of the raw materials transformed into other crystals, and the color changes of ceramic bodies mainly depended on hematite and magnetite. The glass formed at high temperature improved spalling resistance of the ceramic bodies.

The preparation, characteristics and mechanisms of sintered bricks manufactured by Yellow River silt and red mud were studied. The sintering shrinkage, weight loss on ignition, water absorption and compressive strength were tested to determine the optimum preparation condition. Sintering mechanisms were discussed through linear regression analysis. Crystalline components of raw materials and bricks were analyzed by X-ray diffraction. Leaching toxicity of raw materials and bricks were measured according to sulphuric acid and nitric acid method. Radiation safety of the sintered bricks was characterized by calculating internal exposure index and external exposure index. The results showed that at the chosen best parameters (red mud content of 40%, sintering temperature of 1050 °C and sintering time of 2 h), the best characteristics of sintered bricks could be obtained. The weight loss on ignition of sintered bricks was principally caused by the removal of absorbed water and crystal water. The sintering shrinkage of sintered bricks mainly depended on sodium compounds and iron compounds of red mud. The sintering process made some components of raw materials transform into other crystals having better thermostability. Besides, the leaching toxicity and radioactivity index of sintered bricks produced under the optimum condition were all below standards.

Esophageal cancer is characterized by increased oxidative stress and the production of 8-hydroxy-2'-deoxyguanosine (8-OHdG), which is one of the main mutagenic modifications of DNA. We analyzed the predictive value of 8-OHdG expression on postoperative survival of patients with esophageal cancer with univariate and multivariate analysis. The high levels of 8-OHdG are associated with significantly shorter survival time by log-rank test using Kaplan-Meier methods. Moreover, the level of 8-OHdG expression was identified as an independent predictor for esophageal cancer outcome using Cox proportional hazards model analysis (relative risk, 0.294; 95% confidence interval, 0.178-0.487; P = .000). These results suggest that oxidative damage marker of 8-OHdG is a useful prognostic marker in esophageal cancer. The analysis of 8-OHdG levels can help in the identification of patient subgroups that are at high risk for poor disease outcomes.

Herein, we describe the isolation of rare alkaloids, haenamindole and citreoindole, from a South China Sea deep-sea fungus, Penicillium citrinum (MF006), and their structure revision based on detailed spectroscopic and C3 Marfey’s analysis.

Osteosarcoma (OS) is the most common type of primary bone malignancy. The use of multiagent, intensive chemotherapy has markedly improved the long‑term survival rate of patients with OS. However, chemoresistance continues to be the principal reason for poor survival and disease recurrence in patients with OS. Innate or acquired resistance to cisplatin, which is one of the most effective drugs against OS, is common. Understanding the molecular basis underlying cisplatin chemoresistance in OS cells may serve as a basis for the identification of novel therapeutic targets and biomarkers. High expression levels of podocalyxin (PCX) have been shown to be correlated with poor outcome in various types of cancer. A recent study suggested that PCX may contribute to cancer chemoresistance. The present study aimed to explore the role of PCX in OS by determining its effects on cisplatin chemoresistance in OS cells. Stable overexpression and knockdown of PCX were performed in MG‑63 and U2OS human OS cell lines. Overexpression of PCX in the two cell lines significantly increased the half maximal inhibitory concentration (IC50) of cisplatin, cell colony formation, phosphatidylinositide 3‑kinase (PI3K) activity and Akt phosphorylation at serine 473, and decreased cisplatin‑induced cell apoptosis. Furthermore, the effects of PCX were largely attenuated by treatment with the selective PI3K inhibitor BKM120. Conversely, knockdown of PCX expression markedly decreased the IC50 of cisplatin, cell colony formation, PI3K activity and Akt phosphorylation at serine 473, and increased cisplatin‑induced cell apoptosis. In conclusion, the present study was the first, to the best of our knowledge, to provide evidence that PCX promotes cisplatin chemoresistance in OS cells through a PI3K‑dependent mechanism. The results of the present study provided novel insight not only into the functional role of PCX in cancer, but also into the molecular mechanisms underlying OS chemoresistance.

Step‐like current‐voltage characteristics are observed in ac‐driven dynamic voltage bands under certain ac conditions. Fourier analysis reveals that the current steps correspond to frequency‐locked states, which exhibit a period‐adding bifurcation with the dc voltage as a control parameter. This bifurcation is also found to strongly depend on the external ac conditions. It indicates that the vertical transport of ac‐driven weakly‐coupled superlattices provides a rich testing ground for nonlinear physics.

In the intermediate temperature region, an external ac bias induced expansion of dynamic voltage band (DVB) is investigated experimentally in a weakly coupled GaAs/AlAs superlattice. The observed results are explained based on an analysis of general nonlinear dynamics. It suggests that the effect of an external ac bias is to tighten the unstable limit cycle onto the stable fixed point. Beyond a certain critical value, the stable limit cycle is the only stable solution of the system resulting in the observation of self‐sustained current oscillation.

Silicon nitride (Si3N4) is an important thin film materials in the construction of micromachined devices that depend upon low stress thin films. This paper presents the methods to obtain desired low stress levels for use in micromachined devices. By analyzing the mechanism of the stress, we developed the processes by LPCVD, to achieve the quality levels in the applications of MEMS. And the results of this process allowed us to form a low stress film for the fabrications of micro cantilevers, and the applications in the micro mirrors in the MOEMS. At last, the results of the MEMS devices is presented.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The interface formed between the ferromagnetic semiconductor GaMnAs and the organic semiconductor N,N'-diphenyl-N,N'-bis(1-naphthyl)(1,1'-biphenyl)-4,4'-diamine (NPB) was investigated using current transport measurement and ultraviolet photoemission spectroscopy (UPS). The hole injection barrier at a GaMnAs and NPB interface was measured as 0.77 eV by modelling the measured current density-voltage (J-V) characteristics in a GaMnAs/NPB/Al structured device. The vacuum level shift at a GaMnAs/NPB interface was deduced to be 0.54 eV, indicating that a dipole layer exists at the interface. A UPS study gave a vacuum level shift of 0.53 eV and a band offset between the GaMnAs valence band and the highest occupied molecular orbital of NPB of 0.79 eV, in good agreement with the results of J-V measurements. We attribute the vacuum level shift to charge transfer across the interface.

A systematic Mn L-edge x-ray absorption is carried out on carefully prepared Ga0.946Mn0.054As ferromagnetic semiconductors with varying As2∕Ga flux ratio. It is found that the L3 peak of the absorption spectroscopy is enhanced after low temperature (LT) annealing. Furthermore it is shown that a more localized electronic structure nearly like the d5 high-spin state is obtained. It can be attributed to breaking the MnS–MnI pairs during the annealing process. Furthermore the authors present a direct evidence for a slightly increase of the Mn substitutional concentration due to LT annealing.