Epithelial‐to‐mesenchymal transition (EMT) is implicated in a wide array of malignant behaviors of cancers, including proliferation, invasion, and metastasis. Most notably, previou studies have ...indicated that both cancer stem‐like properties and drug resistance were associated with EMT. Furthermore, microRNAs (miRNAs) play a pivotal role in the regulation of EMT phenotype, as a result, some miRNAs impact cancer stemness and drug resistance. Therefore, understanding the relationship between EMT‐associated miRNAs and cancer stemness/drug resistance is beneficial to both basic research and clinical treatment. In this review, we preliminarily looked into the various roles that the EMT‐associated miRNAs play in the stem‐like nature of malignant cells. Then, we reviewed the interaction between EMT‐associated miRNAs and the drug‐resistant complex signaling pathways of multiple cancers including lung cancer, gastric cancer, gynecologic cancer, breast cancer, liver cancer, colorectal cancer, pancreatic cancer, esophageal cancer, and nasopharyngeal cancer. We finally discussed the relationship between EMT, cancer stemness, and drug resistance, as well as looked forward to the potential applications of miRNA therapy for malignant tumors.
In this review, we preliminarily looked into the various roles that the EMT‐associated miRNAs play in the stem‐like nature of malignant cells. Then we reviewed the interaction between drug resistance and EMT‐associated miRNAs with elaborated signal pathways, especially the opposite roles in various cancer types. We finally arrived at a conclusion concerning the relationship between EMT, stemness and drug resistance and discussed the potential application of miRNA therapy for malignant tumors.
Developing high-efficiency and economical non-PGM catalysts for oxygen reduction reaction (ORR) is of great significance for energy conversion and storage devices. In this work, a template-free ...strategy has been developed to prepare Fe, N co-doped hollow spherical carbon (FeNHSC) with a certain curvature, through a simple hydrothermal method and then NH3 activation. The obtained FeNHSC exhibits remarkably improved ORR activity, good long-term stability, and outstanding resistance to methanol crossover, which are much higher than the commercial Pt/C in alkaline medium. The enhancement of the above electrocatalytic performances can be attributed to the curved shell of the synthesized hollow spherical carbon, which contributes to exposure active Fe in form of the Fe–N4 moieties anchored on the carbon. Density functional theory (DFT) calculation results further reveal that the FeNHSC with a curved structure can efficiently boost the ORR rate, compared with the non-curved carbon. For the curved carbon, the positively shifted d-band center (εd) and increased positive surface charges of the Fe sites in form of Fe–N4 structure should be responsible for the curvature-dependent ORR activity. This finding may open a way to fabrication next-generation transition metal-nitrogen-carbon catalysts for clean energies.
•Fe, N co-doped hollow spherical carbon was synthesized by a template-free method.•The catalyst shows excellent ORR activity and high stability in alkaline media.•It exhibits good power density and discharge performance for Zn-air batteries.•DFT results reveal that the curved shell of the carbon results in the performance.
Existing platforms for collaborative BIM design have a centralized system architecture, which suffers cybersecurity risks of design data manipulation and denial of access, leading to a loss of data ...traceability, a decline in design productivity, and project delays. Blockchain is a promising technology to solve such risks by providing decentralized and immutable data storage. However, integrating blockchain with BIM faces a problem that blockchain is inherently unsuitable for storing large-sized design files like BIM models, hindering blockchain from protecting BIM data integrity. Therefore, this paper proposes a distributed common data environment (DCDE) framework for BIM-based design leveraging two distributed technologies: blockchain and Interplanetary File System (IPFS). The DCDE framework guarantees irreversible design changes storage using blockchain while secures design file storage using IPFS. A blockchain transaction data model and a smart contract are also developed within the framework to support DCDE functionalities. Lastly, framework applicability and performance are tested in an illustrative design example. Results show that: (1) DCDE is a feasible solution for secure design collaboration, and (2) DCDE latency (in millisecond-level), TPS (60 transactions per second), and storage cost (12.5 KB per day) are within an acceptable range.
•A distributed common data environment (DCDE) framework is proposed using blockchain and IPFS technologies.•An original transaction data model compliant with ISO 19650 standards is developed for recording design changes.•A smart contract algorithm is developed for design transactions sharing and querying.•The proposed DCDE framework is deployed in a design example to illustrate its feasibility and performance.•Results show that the proposed DCDE is a promising solution for secure decentralized design collaboration.
Abstract
Knots are intricate structures that cannot be unambiguously distinguished with any single topological invariant. Momentum space knots, in particular, have been elusive due to their requisite ...finely tuned long-ranged hoppings. Even if constructed, probing their intricate linkages and topological "drumhead” surface states will be challenging due to the high precision needed. In this work, we overcome these practical and technical challenges with RLC circuits, transcending existing theoretical constructions which necessarily break reciprocity, by pairing nodal knots with their mirror image partners in a fully reciprocal setting. Our nodal knot circuits can be characterized with impedance measurements that resolve their drumhead states and image their 3D nodal structure. Doing so allows for reconstruction of the Seifert surface and hence knot topological invariants like the Alexander polynomial. We illustrate our approach with large-scale simulations of various nodal knots and an experiment which maps out the topological drumhead region of a Hopf-link.
The infrared search and track (IRST) system has been widely used, and the field of infrared small target detection has also received much attention. Based on this background, this paper proposes a ...novel infrared small target detection method based on non-convex optimization with Lp-norm constraint (NOLC). The NOLC method strengthens the sparse item constraint with Lp-norm while appropriately scaling the constraints on low-rank item, so the NP-hard problem is transformed into a non-convex optimization problem. First, the infrared image is converted into a patch image and is secondly solved by the alternating direction method of multipliers (ADMM). In this paper, an efficient solver is given by improving the convergence strategy. The experiment shows that NOLC can accurately detect the target and greatly suppress the background, and the advantages of the NOLC method in detection efficiency and computational efficiency are verified.
Tin disulfide (SnS2) is a promising anode material for sodium-ion batteries because of its high specific capacity. However, the low conductivity and large volume change during reaction with Na+ ions ...greatly limit its practical application. Herein, a multistep templating method has been exploited for the rational design and synthesis of SnS2 nanosheets confined in carbon nanotubes (SnS2@CNTs). To demonstrate the universality of this method, SnS2 nanosheets confined in carbon nanoboxes (SnS2@CNBs) and hollow carbon nanospheres (SnS2@CNSs) have also been synthesized by simply changing the template in the reaction system. Due to their unique structural merits, the SnS2@CNTs, SnS2@CNBs, and SnS2@CNSs show improved sodium storage performance in terms of high specific capacity, good cycling stability, and superior rate capability.
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•SnS2 nanosheets are confined in various hollow carbon nanostructures•Ultrathin SnS2 nanosheets ensure efficient capacitive sodium storage•SnS2-carbon electrodes manifest excellent electrochemical sodium storage performance
Sodium-ion batteries (SIBs) have attracted ever-growing attention as an alternative to lithium-ion batteries in view of the abundant resources and low cost of sodium. One major challenge for SIBs exists in developing efficient anode materials. Tin disulfide (SnS2) is a promising anode material for SIBs because of its high theoretical capacity. However, the low conductivity and huge volume expansion during reaction with Na+ ions significantly hamper its practical application. Here, we develop a facile templating method to effectively confine ultrathin SnS2 nanosheets in carbon nanotubes (SnS2@CNTs), carbon nanoboxes (SnS2@CNBs), and hollow carbon nanospheres (SnS2@CNSs). Benefiting from their unique structural advantages, these SnS2-carbon nanohybrids manifest high specific capacity, good cycling stability, and excellent rate capability. This work might enlighten scientists to exploit high-performance SIB anodes so that SIBs can be used in large-scale energy storage in the near future.
Sodium-ion batteries (SIBs) have attracted enormous attention as an alternative to lithium-ion batteries (LIBs). Recent studies on SIB cathodes have demonstrated performances comparable with their LIB counterparts. One major challenge for SIBs thus resides in exploiting suitable anode materials. Here, we develop a multistep templating method to confine SnS2 nanosheets in different carbon hollow structures including nanotubes, nanoboxes, and hollow nanospheres. Benefiting from their unique structural merits, these SnS2-carbon nanohybrids manifest excellent sodium storage properties.
Infrared imaging plays an important role in space-based early warning and anti-missile guidance due to its particular imaging mechanism. However, the signal-to-noise ratio of the infrared image is ...usually low and the target is moving, which makes most of the existing methods perform inferiorly, especially in very complex scenes. To solve these difficulties, this paper proposes a novel multi-frame spatial–temporal patch-tensor (MFSTPT) model for infrared dim and small target detection from complex scenes. First, the method of simultaneous sampling in spatial and temporal domains is adopted to make full use of the information between multi-frame images, establishing an image-patch tensor model that makes the complex background more in line with the low-rank assumption. Secondly, we propose utilizing the Laplace method to approximate the rank of the tensor, which is more accurate. Third, to suppress strong interference and sparse noise, a prior weighted saliency map is established through a weighted local structure tensor, and different weights are assigned to the target and background. Using an alternating direction method of multipliers (ADMM) to solve the model, we can accurately separate the background and target components and acquire the detection results. Through qualitative and quantitative analysis, experimental results of multiple real sequences verify the rationality and effectiveness of the proposed algorithm.
In contrast to summer smog, the contribution of photochemistry to the formation of winter haze in northern mid-to-high latitude is generally assumed to be minor due to reduced solar UV and water ...vapor concentrations. Our comprehensive observations of atmospheric radicals and relevant parameters during several haze events in winter 2016 Beijing, however, reveal surprisingly high hydroxyl radical oxidation rates up to 15 ppbv/h, which is comparable to the high values reported in summer photochemical smog and is two to three times larger than those determined in previous observations during winter in Birmingham (Heard et al. Geophys. Res. Lett. 2004, 31, (18)), Tokyo (Kanaya et al. J. Geophys. Res.: Atmos. 2007, 112, (D21)), and New York (Ren et al. Atmos. Environ. 2006, 40, 252–263). The active photochemistry facilitates the production of secondary pollutants. It is mainly initiated by the photolysis of nitrous acid and ozonolysis of olefins and maintained by an extremely efficiently radical cycling process driven by nitric oxide. This boosted radical recycling generates fast photochemical ozone production rates that are again comparable to those during summer photochemical smog. The formation of ozone, however, is currently masked by its efficient chemical removal by nitrogen oxides contributing to the high level of wintertime particles. The future emission regulations, such as the reduction of nitrogen oxide emissions, therefore are facing the challenge of reducing haze and avoiding an increase in ozone pollution at the same time. Efficient control strategies to mitigate winter haze in Beijing may require measures similar as implemented to avoid photochemical smog in summer.
Big earthquakes often excite the acoustic resonance between the earth’s surface and the lower atmosphere. The perturbations can propagate upward into the ionosphere and trigger ionospheric anomalies ...detected by dual-frequency GPS observations, but coseismic ionospheric disturbance (CID) directivity and mechanism are not clear. In this paper, the ionospheric response to the Mw = 7.9 Alaska earthquake on 23 January 2018 is investigated from about 100 continuous GPS stations near the epicenter. The fourth-order zero-phase Butterworth band-pass filter with cutoffs of 2.2 mHz and 8 mHz is applied to obtain the ionospheric disturbances. Results show that the CIDs with an amplitude of up to 0.06 total electron content units (TECU) are detected about 10 min after the Alaska earthquake. The CIDs are as a result of the upward propagation acoustic waves triggered by the Rayleigh wave. The propagation velocities of TEC disturbances are around 2.6 km/s, which agree well with the wave propagation speed of 2.7 km/s detected by the bottom pressure records. Furthermore, the ionospheric disturbances following the 2018 Mw = 7.9 Alaska earthquake are inhomogeneous and directional which is rarely discussed. The magnitude of ionospheric disturbances in the western part of the epicenter is more obvious than in the eastern part. This phenomenon also corresponds to the data obtained from the seismographs and bottom pressure records (BPRs) at the eastern and western side of the epicenter.
Aiming at improving the strength-plasticity match in the as-cast state of the most widely used Ti-6Al-4V the present work designs Ti-Al-V-Zr alloys on the basis of the dual-cluster formula of ...Ti-6Al-4V, α-{Al-Ti12（AlTi2）}12+β-{Al-Ti14（V2Ti）}5: first, the alloys are more biased towards α-Ti by decreasing the number of β unit to 2, then, the stability of β-Ti is improved by increasing the number of V atoms in β unit to 3, and finally, Zr（x=1-5） replaces Ti in the β unit. Finally α-{Al-Ti12（AlTi2）}15-β-{AlTi14-x ZrxV3)}2 is obtained, Ti-（6.64-6.82）Al-（2.42-2.35）V-（1.44-7.02）Zr（mass fraction,%） alloy is designed. The alloy ingots are prepared by melting in a non-consuming vacuum are furnace, and the alloy bars are suction-cast in copper mould. The results show that the alloys are all in α' martensite structure, showing morphologies changing from acicular Widmannstatten structure at lower Zr contents to net-basket structure at higher Zr contents. Among the designed alloys, Ti-6.64Al-2.35V-7.02Zr（x=5） with
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