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Effective photosensitizers (PSs) are at the heart of the key role of photo-driven antibacterial therapy. However, relative high temperature required for bactericidal activity, stimulating at multiple wavelengths, and multi-step synthesis of the photothermal and photodynamic agents challenge their applications in antibacterial treatment. In this study, silver nanoparticles (AgNPs) functionalized by kaempferol (Kae) are implanted into Prussian blue (PB) to construct photo-responsive nanocubes (AgPB) by a simple synthetic process. The as-synthesized AgPB nanocomposites were found to have an average size of ∼140 nm, and the particle size range of the loaded-AgNPs was 5–15 nm. The structure of AgPB was characterized, and the photothermal and photodynamic evaluation of antibacterial activity of AgPB was investigated under single 808 nm near-infrared (NIR) light. By adjusting the doping ratio of AgNPs, the band gap can be tuned from 2.78 to 2.56 eV to further enhance the photothermal conversion of AgPB and its ability to generate reactive oxygen species (ROS). When compared with AgPB without NIR illumination, in vitro antibacterial studies by using Escherichia coli and Staphylococcus aureus showed that AgPB under 808 nm NIR light could rapidly heat up to 50 °C, enhance the formation of ROS, and promote the ion release amount of Fe2+, Fe3+, and Ag+ to increase oxidative stress, leading to inhibition of bacterial proliferation significantly. Both E. coli and S. aureus were completely killed within 10 min. Moreover, the biofilm formation was remarkably inhibited, and the eradication ratio against E. coli and S. aureus biofilms was 69.73 and 60.01%, respectively. In addition, the hemolytic activity test proved that AgPB had good biocompatibility. The results showed that AgPB with triple bactericidal modalities could expand the application of PSs and serve as a promising nanocomposite for antibacterial therapy. [ABSTRACT FROM AUTHOR]

Two phases of diabase-sill-forming magmatism are recorded within the Badu anticline where magmas were emplaced into upper Palaeozoic carbonates and clastic rocks of the Youjiang fold-and-thrust belt in the SW South China Block, China. Zircons from these diabase units yield weighted mean U–Pb ages of 249.2±2.0 Ma and 187.1±3.3 Ma, and magmatic oxygen fugacity values from ‒20 to ‒6 (average of ‒12, equating to FMQ +5) and ‒20 to ‒10 (average of ‒15, equating to FMQ +2), respectively. These data indicate that the sills were emplaced during Early Triassic and Early Jurassic times. The discovery of c. 250 Ma mafic magmatism in this area was probably related to post-flood-basalt extension associated with the Emeishan mantle plume or rollback of the subducting Palaeo-Tethys slab. The c. 190 Ma diabase sills indicate that the southwestern South China Block records Early Jurassic mafic magmatism and lithospheric extension that was likely associated with a transition from post-collisional to within-plate tectonic regimes. The emplacement of diabase intrusions at depth may have driven hydrothermal systems, enabling the mobilization of elements from sedimentary rocks and causing the formation of a giant epigenetic metallogenic domain. The results indicate that high-oxygen-fugacity materials within basement rocks caused crustal contamination of the magmas, contributing to the wide range of oxygen fugacity conditions recorded by the Au-bearing Badu diabase. In addition, data from inherited xenocrystic zircons within the Badu diabase and detrital zircons from basement rocks suggest that the Neoproterozoic Jiangshao suture extends to the south of the Badu anticline. [ABSTRACT FROM AUTHOR]

Tin sulfide semiconductor nanowires (NWs) have been widely investigated for photodetection applications because of their good optical and electrical properties. Herein, we synthesized n-type SnS2 NWs and then fabricated SnS2 NW photodetectors with a ferroelectric polymer side-gate. The strong electric field induced by ferroelectric polymer can effectively suppress the dark current and improve the detectivity in SnS2 NW photodetectors. The photodetectors after polarization depletion exhibit a high photoconductive gain of 4.0 × 105 and a high responsivity of 2.1 × 105 A W−1. Compared with devices without polarization depletion, the detectivity of polarization-depleted photodetectors is improved by at least two orders of magnitude, and the highest detectivity is 1.3 × 1016 Jones. Further, the rise and fall time are 56 and 91 ms respectively, which are about tens of times faster than those without polarization depletion. The device also shows a good spectral response from ultraviolet to near-infrared. This study demonstrates that ferroelectric materials can enhance optoelectronic properties of low-dimensional semiconductors for high-performance photodetectors.

Bottom-like flowing pressure (BHFP) prediction for multi-stage fractured horizontal shale gas with constant rate production is a key problem of stable production period estimation. Based on the transient linear flow theory of multi-stage fractured horizontal shale gas, the rate-time superposition function (Qg・t0.5)sup is proposed, a type curve identification charts of pseudopressure difference [m(pi)-m(pwf)]-rate-time superposition function (Qg・t0.5)sup is established, a parameter group of m which could reflect reservoir properties and fractured effect is determined, an BHFP prediction analytical solution function for constant rate production shale gas well is constructed. This method is applied in constant rate production and variable rate production shale gas wells, the results show that there is an excellent coincidence rate between predicted BHFP and monitored BHFP, which is above 95%, and the forecasting precision of stable production period is above 90%. This BHFP prediction method has an important guiding significance for stable production period prediction, rational proration of multi-stage fractured horizontal shale gas well with constant rate production. [ABSTRACT FROM AUTHOR]

Gas content is a key parameter for shale reserves estimation，production prediction and gas rate decline analysis. The storage mechanisms in shale is contained free and adsorption，and there are many different gas content testing methods such as gravimetric isotherm method，volume isotherm method and traditional testing method in field. In this study，a new shale gas content lab testing method is proposed based on measuring the gas volume changes during shale gas desorption. In this new method，cylindrical shale cores are used for simulating the influences of temperature，pressure，moisture content，real pore structure on total gas content，negative adsorption anomalies are eliminated by using this method. The experimental results revealed that adsorption gas content increased with pressure and the volume of adsorption gas content is at equilibrium and does not increase while the pressure is up to 12MPa. There is a positive relationship between adsorption gas content and TOC，and a negative relationship between adsorption gas content and temperature and moisture content. Adsorption of methane is higher than the nitrogen adsorption in shale. At a temperature of 20℃，under pressure of 30MPa，the adsorption gas content of Longmaxi shale in Jiaoshiba is 1.8-3.1m3/t and total gas content is 5.1-6.5m3/t，and about 40% of the total volume is adsorbed gas. [ABSTRACT FROM AUTHOR]

Liaodong Peninsula on the northeastern North China Block that witnessed the spectacular Late Mesozoic tectonics is a key area to probe the transition from compression to extension. Borehole data clearly reveals that the Cambrian limestone overlay the Jurassic limestone, which identified the Yuantai thrust system in Liaodong Peninsula. Zircon grains from a granodiorite dike that intruded the thrust system yielded U-Pb age of 128.3 ± 1.3 Ma, further constraining the timing of the thrusting between Late Jurassic to early Early Cretaceous. A detailed field study of three-dimensional fault-zone exposures in the Zhayao tectonic window are conducted to decipher the thrust tectonics before the extension in Liaodong Peninsula. The key observations are: (1) meter-scale asymmetric folds in deformed mid-Cambrian rocks; (2) decameter-scale recumbent folds and secondary imbricate thrusts in deformed Middle Jurassic rocks; and (3) non-foliated breccia, fault gouge, and brittle porphyroclasts adjacent to fault planes. The combined brittle–ductile style of deformation indicates that the fault zone operated under near-surface conditions. In addition, we infer that the folds were formed first at the propagating fault tip and subsequently dismembered by normal faults. We interpret the Zhayao thrust, which is located around the margin of the tectonic window, as the frontal thrust of the Yuantai thrust system. Furthermore, by applying the theory of fault-related folds, we deduce that the Zhayao frontal thrust is a secondary duplex. Based on our field observations and borehole data, we propose an imbricate thrust model for the fold-and-thrust belt of the southern Liaodong Peninsula. The structural data indicate that the transport direction of the Yuantai thrust system was top-to-the-southeast, suggesting that the thrust system was resulted due to northwest-ward subduction of the paleo-Pacific plate during the Mesozoic. [ABSTRACT FROM AUTHOR]

Objective: To search for the best program increasing clinical therapeutic effect on vertebrobasilar insufficiency (VBI) and to study the mechanism., Methods: The patients were randomly divided into an acupuncture plus massage group, an acupuncture group and a massage group. Their therapeutic effects were observed and compared. And transcranial Doppler (TCD) was used for detection of systolic flow velocity (Vs), enddiastolic peak flow velocity (Vd), mean peak flow (Vm) and pulsatility index (PI) before and after treatment., Results: The cured rate and the total effective rate in the acupuncture plus massage group were significantly higher than the acupuncture group and the massage group (P < 0.05). And there were significant differences in Vm, PI and DI in the left vertebral artery (LVA), the right vertebral artery (RVA) and the basilar artery (BA) before and after treatment (P < 0.01)., Conclusion: Acupuncture combined with massage can improve Vm, PI, DI of VA-BA and the clinical therapeutic effect on VBI as well. It is superior to the simple acupuncture therapy and simple massage therapy. At present, it is one of the best therapy for VBI.