The increased seismic activity of the last ~10 years in Changning county of Sichuan Province comprised just small (mostly ML < 5.0) injection‐induced earthquakes. The MW 5.7 earthquake on June 17, ...2019, is the largest event ever reported there. Moment tensor of the mainshock was remarkably dominated by a compensated linear vector dipole. We resolve its fine structure showing it was a doublet, allowing approximation by a thrust‐ and strike‐slip subevent. The mainshock nucleated as thrust faulting, which (together with the largest aftershocks) can be linked with previously known reverse faults, favorably oriented to regional stress field. Contrarily, the strike‐slip segment of the mainshock, less favorably oriented, was probably facilitated by elevated pore pressure due to previous injections. Shallow active strike‐slip faulting, not yet mapped in the region, is a new feature, important for future hazard assessment.
Plain Language Summary
Changning county in Sichuan Basin belongs to major salt‐producing resources, with water injection wells drilled to ~3‐km depths. Enhanced occurrence of small earthquakes was observed in the last ~10 years. However, on June 17, 2019, a damaging earthquake struck the region. Seismic agencies reported diverse focal mechanisms and pointed to departures from shear faulting, typical for tectonic events. To understand these enigmatic features, we modeled records from 12 broadband seismic stations, adding over 100 first‐motion polarities. We found that the earthquake was very shallow (~4 km) and consisted of two shear events: the initial thrust faulting and the following strike‐slip faulting along an SE‐NW trending near‐vertical plane, aligned with aftershocks. The initial episode was “normal,” expected on existing faults and supported by tectonic stresses of the region. Contrarily, the significant strike‐slip faulting appears to be rather “abnormal,” probably facilitated by the initial shock and by elevated pressure of underground fluids. The 2019 earthquake provided a rare opportunity to illuminate interplay between long‐lasting water injections, tectonic stress, complexity of existing faults, and their dynamic interactions. That is how seismology aims at making industrial activities sustainable and safe.
Key Points
This is the so‐far largest earthquake in a salt‐mining area where seismicity has been increased in previous 10 years by injection‐induced events
Mainshock nucleated as a thrust, then rupturing a previously unknown strike‐slip fault, suboptimally oriented to regional stress field
The complex nature of the event explains its small double‐couple component and diversity of focal mechanisms across reporting agencies
Platinum-based anticancer drugs, including cisplatin, carboplatin, oxaliplatin, nedaplatin, and lobaplatin, are heavily applied in chemotherapy regimens. However, the intrinsic or acquired resistance ...severely limit the clinical application of platinum-based treatment. The underlying mechanisms are incredibly complicated. Multiple transporters participate in the active transport of platinum-based antitumor agents, and the altered expression level, localization, or activity may severely decrease the cellular platinum accumulation. Detoxification components, which are commonly increasing in resistant tumor cells, can efficiently bind to platinum agents and prevent the formation of platinum-DNA adducts, but the adducts production is the determinant step for the cytotoxicity of platinum-based antitumor agents. Even if adequate adducts have formed, tumor cells still manage to survive through increased DNA repair processes or elevated apoptosis threshold. In addition, autophagy has a profound influence on platinum resistance. This review summarizes the critical participators of platinum resistance mechanisms mentioned above and highlights the most potential therapeutic targets or predicted markers. With a deeper understanding of the underlying resistance mechanisms, new solutions would be produced to extend the clinical application of platinum-based antitumor agents largely.
In privacy protection methods based on location services, constructing anonymous areas using location information shared by collaborative users is the main method. However, this collaborative process ...not only increases the risk of mobile users' location privacy being leaked, but also reduces positioning accuracy. In response to this problem, we propose a balancing strategy, which transforms the problem of protecting mobile users' location privacy and improving positioning accuracy into a balance issue between location privacy and positioning accuracy. The cooperation of mobile users with different collaborating users is then modeled as an objective optimization problem, and location privacy and positioning accuracy are evaluated separately to make different selection strategies. Finally, an optimization function is constructed to select the optimal selection strategies. Experimental results show that our proposed strategy can effectively achieve the balance between location privacy and positioning accuracy.
Niobium pentoxides (Nb2O5) as anode materials has attracted tremendous research interest due to its great potential in rate capability and cyclic durability. Nevertheless, the low electrical ...conductivity and weak structural controllability of Nb2O5 hinders its practical application. Herein, amorphous Nb2O5 thin films are conformally deposited on carbon nanotubes (CNTs) by controlled atomic layer deposition (ALD) and three types of crystalline Nb2O5@CNTs composites are obtained by post-deposition annealing. Moreover, the effects of deposition temperature and annealing temperature on the crystal structure and surface morphology of Nb2O5@CNTs are investigated. Based on these, the electrochemical performances of Nb2O5@CNTs composites as anode materials are compared in lithium half cells. Impressively, ultrathin and uniform Nb2O5 nanocrystal film with hexagonal (TT) phase on CNTs delivers a capacity of 325.1 mAh g−1 at 0.2 A g−1. Even at a high current density of 3 A g−1, a stable capacity of 170 mAh g−1 is still achieved over 4000 cycles. Its high-rate and long-life lithium ion storage is mainly attributed to the synergistic effects of carbon nanotubes, TT-phase Nb2O5, and ultrathin film structure. Therefore, this synthetic strategy facilitates the development of Nb2O5 as anode materials for high-rate and long-life lithium/sodium ion batteries.
Polyps are abnormal tissue clumps growing primarily on the inner linings of the gastrointestinal tract. While such clumps are generally harmless, they can potentially evolve into pathological tumors, ...and thus require long-term observation and monitoring. Polyp segmentation in gastrointestinal endoscopy images is an important stage for polyp monitoring and subsequent treatment. However, this segmentation task faces multiple challenges: the low contrast of the polyp boundaries, the varied polyp appearance, and the co-occurrence of multiple polyps. So, in this paper, an implicit edge-guided cross-layer fusion network (IECFNet) is proposed for polyp segmentation. The codec pair is used to generate an initial saliency map, the implicit edge-enhanced context attention module aggregates the feature graph output from the encoding and decoding to generate the rough prediction, and the multi-scale feature reasoning module is used to generate final predictions. Polyp segmentation experiments have been conducted on five popular polyp image datasets (Kvasir, CVC-ClinicDB, ETIS, CVC-ColonDB, and CVC-300), and the experimental results show that the proposed method significantly outperforms a conventional method, especially with an accuracy margin of 7.9% on the ETIS dataset.
s
High-
k
metal oxide films are vital for the future development of microelectronics technology. In this work, ZrO
2
films were grown on silicon by atomic layer deposition (ALD) using ...tetrakis(dimethylamido)zirconium and ozone as precursors. The relatively constant deposition rate of 0.125 nm/cycle is obtained within the ALD temperature window of 200–250 °C. The film thickness can be precisely controlled by regulating the number of ALD cycle. The ZrO
2
films formed at 200–250 °C have an O/Zr atomic ratio of 1.85–1.9 and a low content of carbon impurity. ZrO
2
film begins to crystallize in ALD process above 210 °C, and the crystal structure is changed from cubic and orthorhombic phases to monoclinic and orthorhombic phases with increasing the deposition temperature to 350 °C. Moreover, the effect of annealing temperature on dielectric properties of ZrO
2
film was studied utilizing ZrO
2
-based MIS device. The growth of the interface layer between ZrO
2
and Si substrate leads to the decrease in the capacitance and the leakage current of dielectric layer in the MIS device after 1000 °C annealing. ZrO
2
film exhibits the relatively high dielectric constant of 32.57 at 100 kHz and the low leakage current density of 3.3 × 10
−6
A cm
−2
at 1 MV/cm.
Engineering wearable devices that can wirelessly track intraocular pressure and offer feedback-medicine administrations are highly desirable for glaucoma treatments, yet remain challenging due to ...issues of limited sizes, wireless operations, and wireless cross-coupling. Here, we present an integrated wireless theranostic contact lens for in situ electrical sensing of intraocular pressure and on-demand anti-glaucoma drug delivery. The wireless theranostic contact lens utilizes a highly compact structural design, which enables high-degreed integration and frequency separation on the curved and limited surface of contact lens. The wireless intraocular pressure sensing modulus could ultra-sensitively detect intraocular pressure fluctuations, due to the unique cantilever configuration design of capacitive sensing circuit. The drug delivery modulus employs an efficient wireless power transfer circuit, to trigger delivery of anti-glaucoma drug into aqueous chamber via iontophoresis. The minimally invasive, smart, wireless and theranostic features endow the wireless theranostic contact lens as a highly promising system for glaucoma treatments.
Over 12 years of continuous monitoring of Changbaishan volcano in the border region of China and North Korea by means of volcanic seismicity, ground deformation, and volcanic gas geochemistry yields ...new evidence for magmatic unrest of the volcano between 2002 and 2006. In this so‐called “active period,” the frequency of volcanic earthquakes increased by about 2 orders of magnitude compared to that of the background “inactive periods.” The active period was also accompanied by ground inflation, high values of CO2, He, H2, and high ratios of N2/O2 and 3He/4He in volcanic gases released from three hot springs near the caldera rim. The monitoring evidence implies pressurization of the magma chamber, possibly caused by incremental magma recharge. The ground deformation data from both GPS and precise leveling are modeled to suggest the corresponding deformation source is at 2–60 km depth beneath the volcano's summit, where earthquake swarms were detected in 2002 and 2003. Our findings suggest that the magma chamber beneath Changbaishan volcano has awakened and resumed activity after remaining dormant since AD 1903. There is an urgent need to keep close watch on this active and very hazardous volcano in northeast China.
Key Points
The unrest of Changbaishan volcano during 2002‐2006 was detected
The unrest process may be a long term precursor of eruptive activity in future
Need to keep close watch on the volcano
In recent years, the continuous occurrence of multi-drug resistance in the clinic has made people pay more attention to the transporter. Changes in the expression and activity of transporters can ...cause corresponding changes in drug pharmacokinetics and pharmacodynamics. The drug-drug interactions (DDI) caused by transporters can seriously affect drug effectiveness and toxicity. In the development of pharmaceutical preparations, people have increasingly concerned about the effects and regulation of transporters in drug effects. To improve the targeting and physicochemical properties of drugs, the development of targeted agents is very rapid. Among them, novel nano-formulations are the best. With the continuous innovation and development of nano-formulation, its application has become more and more extensive. Nano-formulation has exerted certain advantages in the drug development based on transporters, and is also involved in the combination of targeted transporters. This review focuses on the application of novel nano-agents targeting transporters and the introduction of drug-transporter-based nano-formulations.
Some medicines enter or exit target cells through transporters. Nano-agents targeting transporters can enhance the targeted uptake of the drug while prevent the efflux of it. Display omitted
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