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In this work, the support vector machine (SVM) method is adopted to separate BL Lacertae objects (BL Lacs) and flat spectrum radio quasars (FSRQs) in the plots of the photon spectrum index against the photon flux, α ph ∼ log F , those of the photon spectrum index against the variability index, α ph ∼ log V I and those of the variability index against the photon flux, log V I ∼ log F . Then, we used the dividing lines to distinguish BL Lacs from FSRQs in the blazar candidates of uncertain types from the Fermi/LAT catalogue. Our main conclusions are: 1. We separate BL Lacs and FSRQs by α ph = − 0.123 log F + 1.170 in the α ph ∼ log F plot, α ph = − 0.161 log V I + 2.594 in the α ph ∼ log V I plot and log V I = 0.792 log F + 9.203 in the log V I ∼ log F plot. 2. We obtain 932 BL Lac candidates and possible BL Lac candidates, and 585 FSRQ candidates and possible FSRQ candidates. 3. Discussion is given regarding comparisons with the literature. [ABSTRACT FROM AUTHOR]

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]

Orogenic growth, characterized by formation and forward propagation of fold‐thrust belts and foreland basins, is predicted by wedge models of thrust systems. The growth of the Nanpanjiang fold‐thrust belt and foreland basin system of the Indosinian orogenic belt in the southwestern South China remains poorly understood. The development of the Indosinian foreland system remains underappreciated due to few constraints on structural styles, kinematics and ages. Surface cross sections, seismic profiles and detrital zircon data are presented to address the structural styles and evolution of the Indosinian foreland system. The results reveal that the fold‐thrust belt is characterized by fault‐related folds with deeper duplexes and shallower imbricates, which yield a NNE‐SSW regional shortening magnitude of ∼36%. Our new constraints indicate that the Nanpanjiang region experienced multi‐staged thrusting during the Indosinian orogeny (D1). The D11 affected the southernmost southern fold‐thrust belt, producing thick‐skinned thrusts involving Neoproterozoic basement and initiating the Nanpanjiang foreland basin. During the D12, NNE‐verging thick‐skinned thrusting continued and was followed by thin‐skinned thrusting in the northern fold‐thrust belt. Locally preserved foreland basin deposits at the northernmost Nanpanjiang Basin define D13. The progressive D14 co‐axially deformed the residual basin into a wide and gentle syncline. Thus, the progressive D11 to D14 deformation sequence of NNE‐verging in‐sequence thrusting and foreland basin migration describe the kinematic and dynamic relationship between fold‐thrust belt and foreland basin during the Indosinian tectonic event. Indosinian D1 structures were subsequently refolded by the Yanshanian tectonic event (D2), forming N‐ to NE‐striking cleavage and arcuation of D1 fold axes. Key Points: The Nanpanjiang fold‐thrust belt and its associated foreland basin migrated NNE‐ward during the Middle Triassic to Early JurassicIndosinian deformation produced an orogenic wedge with a thick‐skinned hinterland belt, a thin‐skinned foreland belt and shortening of 36%In‐sequence thrusting and foreland‐propagation (237–186 Ma) led to incorporation of the Nanpanjiang foreland basin into the fold‐thrust belt [ABSTRACT FROM AUTHOR]

The Cenozoic evolution of SE Asia is marked by thousands of kilometres extension on the continental margin, including normal faults, half‐grabens, and volcanic rocks, but dating of brittle faults in the shallow crust is difficult because of a lack of synkinematic minerals. The Cenozoic extension in the Youjiang fold‐thrust belt in southwest China is marked by brittle normal faults and half‐grabens filled with Paleogene sediments in the region. Here, we identified a strongly weathered mafic sill that was truncated by normal faults in the fold‐thrust belt and present the age and chemistry of zircons from a weathered sill. The zircons from the sill yielded a mean age of ~35 Ma. Integrating cross‐cutting relationship and zircon U–Pb dating suggest that the Cenozoic extension was initiated later than ~35 Ma in Youjiang fold‐thrust belt in southwest China. Combined with structural analysis and previous fission track data in the region, we suggest that the normal faults in this study provide evidence of surface fault activity of Cenozoic extension in SE Asia caused by retreat of a trench system. Furthermore, this study provides a case study to discuss how to decipher brittle normal faulting using zircon geochronology and structural and textural analysis from the mesoscale to the microscale. [ABSTRACT FROM AUTHOR]

Remote sensing techniques are widely used during petroleum exploration. However, limitations in spectral and spatial resolution mean that these techniques are used mainly to detect hydrocarbons either indirectly or under laboratory conditions. To investigate the spectral signatures of natural hydrocarbon-bearing features, we took spectral measurements from oil seeps and associated hydrocarbon-bearing materials in Karamay city, northwest China. The hydrocarbon content of 16 hydrocarbon-bearing samples was also determined to study the relationship between hydrocarbon content and spectral absorption. The results reveal a positive correlation between spectral absorption intensities at 1725 nm and hydrocarbon contents of >1 wt%. Thus, surface hydrocarbon content can be direct detection above a detection limit of around 1 wt% using this method. This result is not only instructive for petroleum exploration, but also important for environmental protection. [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]

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]

The Indosinian orogeny marks the termination of marine deposition and the accumulation of lower Permian to Late Triassic clastic sediments in the Youjiang Basin, South China Block. Major and trace element compositions of Early to Middle Triassic sedimentary clastic rocks from Youjiang Basin were analysed to constrain their provenance and tectonic setting. Argillaceous samples have low SiO 2 (average 56.95 wt.%), Al 2 O 3 (average 15.15 wt.%), and Fe 2 O 3 T + MgO (average 11.54 wt.%) contents, and high K 2 O/Na 2 O (average 15.61) and Al 2 O 3 /SiO 2 (average 0.27) ratios, similar to mudstones from continental arc basins. Arenaceous samples have moderate SiO 2 (average 76.98 wt.%), Al 2 O 3 (average 8.41 wt.%), and Fe 2 O 3 T + MgO (average 5.29 wt.%) contents, and moderate Al 2 O 3 /SiO 2 (average 0.11) and K 2 O/Na 2 O (average 15.26) ratios, identical to those of graywackes from continental island arcs or active continental margins. Both the argillaceous and arenaceous samples have low CIA values (57–85) and relatively high ICV values (0.69–2.11), indicating that the source rocks experienced weak chemical weathering and the sedimentary detritus was derived from an immature source. Compared with late Permian to Early Triassic South China granitoids and upper crust, the samples have lower contents of high-field-strength elements (e.g., Zr, Hf, Nb, and Ta) and large ion lithophile elements (e.g., Rb, Sr, Ba, Th, U, and Pb). However, their relatively high Rb concentrations (>51 ppm), and low Rb/Sr (0.16–4.19) and Th/U (2.66–5.21) ratios, are indicative of an igneous source from a continental arc that underwent weak chemical weathering. Both the argillaceous and arenaceous samples are moderately enriched in light rare earth elements and show relatively flat chondrite-normalized heavy rare earth element patterns (La N /Yb N = 6.61–17.35; average 10.61) with strong negative Eu anomalies (Eu/Eu * = 0.54–0.89; average 0.73). In tectonic discrimination diagrams, including Th–Sc–Zr/10 and La–Th–Sc plots, the geochemical data suggest that the clastic rocks were deposited in a continental arc or margin setting. Thus, we infer that Early to Middle Triassic sediments in the Youjiang foreland basin record the transition from late Permian and Early Triassic subduction to Middle Triassic collision at the southwestern margin of the South China Block. [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]

The southwestern part of the South China Block (SCB) records Triassic and subsequent deformations and is a key region that provides evidence of the post-amalgamation tectonic evolution of Southeast Asia. Here, we outline the tectonothermal evolution of early Mesozoic orogenesis in this region using structural analysis and fission track thermochronology. This region is divided into three tectonic units (south to north): the Youjiang Fold-and-Thrust Belt (YFTB), the Qianzhong Massif (QZM), and the Thin-skinned Thrust Belt (TTB) of the southeastern Sichuan Basin, all three of which record three deformation events, here termed D 1 , D 2 , and D 3 . D 1 deformation is represented by Triassic top-to-the-north thrusts (F 1 ) and fault-related folds (f 1 ) that are indicative of N–S shortening. The intensity of deformation decreases toward the north. The subsequent D 2 and D 3 deformations are marked by Cretaceous top-to-the-NW thrusting and fault-propagation folding, and Cenozoic NE–SW trending normal faults (F 3 ), respectively. The temperature–time ( t – T ) path obtained by apatite fission-track modeling of samples from the YFTB, QZM, and TTB areas provides evidence of uplift and denudation. The D 1 deformation at ∼230–210 Ma is characterized by buried thrusts within the relatively stable YFTB and QZM, and an increase in depth of the TTB. This was coeval with the Late Triassic northward migration of uplift and denudation that is evidenced by a Late Triassic stratigraphic gap within the YFTB, a thin layer of coarse-grained continental clastics within the QZM, and a thick layer of clastic rocks within the TTB. The study area records a Triassic thrust system (D 1 ) that progressively migrated northwards and represents a foreland fold-and-thrust belt that formed during the Indochina–SCB collision. This initial deformation was subsequently overprinted by Late Jurassic to Cretaceous NW–SE thrusting (D 2 ) and the development of Cenozoic NW–SE extensional structures (D 3 ). [ABSTRACT FROM AUTHOR]

• The Late Triassic western Sichuan Basin was a foreland basin at the southern front of the Qinling Orogenic Belt. • The Late Triassic western Sichuan foreland basin formed at 228–208 Ma. • The depocentres migrated southward along the direction perpendicular to the Qinling orogen. • The proto-type basin of the Late Triassic western Sichuan foreland basin was elongated along the E-W direction. The Upper Triassic Xujiahe Formation is a succession of continental clastic rocks in the western Sichuan Basin, China. This formation has previously been regarded as deposited in a foreland basin linked to the NE-SW-striking Longmen Shan Thrust Belt. However, this hypothesis is questionable due to the presence of faults within the Longmen Shan Thrust Belt. Focusing on the Late Triassic proto-basin, we obtained new data from both outcrops and boreholes, which provide information on the sedimentary facies and provenance in the basin. The results show that the basin was originally striking E-W and that the depocentre migrated southward during the Late Triassic. Palaeocurrent indicators and detrital zircon age data reveal that the Upper Triassic strata were derived mainly from the Qinling Orogenic Belt, with a minor component of detritus derived from the South China Block. Detrital zircon U-Pb ages of ~228 Ma, from the bottom of the Xujiahe Formation, constrain the timing of onset of clastic deposition. Our results suggest that the Late Triassic western Sichuan Basin was a foreland basin at the southern front of the Qinling Orogenic Belt. [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.