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Objective Since the collision and compression of the Indo-European continental plates, the Qinghai-Tibetan Plateau has experienced uplift and intra-land deformationSince the collision and compression of the Indo-European continental plates, the Qinghai-Tibetan Plateau has experienced uplift and intra-land deformation. Similarly, the Sichuan-Yunnan block underwent lateral escape and rotationSince the collision and compression of the Indo-European continental plates, the Qinghai-Tibetan Plateau has experienced uplift and intra-land deformation. Similarly, the Sichuan-Yunnan block underwent lateral escape and rotation. Although extensive paleomagnetic studies have been conducted on the rotation of the central and western parts of the Sichuan-Yunnan rhombic block, less attention has been paid to the rotation of its eastern partSince the collision and compression of the Indo-European continental plates, the Qinghai-Tibetan Plateau has experienced uplift and intra-land deformation. Similarly, the Sichuan-Yunnan block underwent lateral escape and rotation. Although extensive paleomagnetic studies have been conducted on the rotation of the central and western parts of the Sichuan-Yunnan rhombic block, less attention has been paid to the rotation of its eastern part. This study employs fluvial geomorphology, which is highly sensitive to mass rotation, to investigate the rotation and uplift in the Laoyingshan region, situated in the eastern part of the Sichuan-Yunnan block. Methods A 30 m resolution digital elevation model (DEM) was used to identify and analyze 22 basins in the study area. Four geomorphological parameters were examined: local topographic relief ratio, longitudinal profile, normalized steepness index, and basin azimuth. Results (1) According to regional topographic relief, the low-relief area in the Laoyingshan region is mainly located near the Sijia River and the Baizai River on the western side, whereas the high-relief area is mainly found near the Dabai River and the Gongshan River on the eastern side of the Laoyingshan. The relief around the Dabai and Gongshan Rivers was greater than that around the Sijia River on the western side of Laoyingshan. (2) The normalized steepness index in the Laoyingshan area gradually decreased from north to south. The high-value areas are primarily located near Awang and Jinyuan, corresponding to the east and west branches of the Xiaojiang Fault. In contrast, the low-value areas were mainly distributed at the top of the Laoyingshan and south of the Baozai River in the study area. (3) The results of the river longitudinal profile indicated that the average surface uplift of the area was approximately 358 m. (4) Based on the results of the watershed azimuth angle, the Laoyingshan area underwent a counterclockwise rotation of approximately 15°. Conclusion The analysis suggests that since the Late Miocene, the western region of the Sichuan-Yunnan block, located west of the Yuanmou Fault, has experienced fewer effects from strike-slip faults and has predominantly undergone clockwise rotation. Conversely, the eastern region of the Sichuan-Yunnan block, influenced by strike-slip faults, underwent counterclockwise rotation with differential uplift. [ Significance] The fluvial geomorphological index outlines the tectonic rotation of the eastern Sichuan-Yunnan block.

Cerebellar degeneration-related protein 1 antisense (CDR1as) is an important member of the circRNAs family, also known as cirs-7. Its main function in vivo is to act as a mir-7 sponge. Accumulated studies show that CDR1as is closely related to various diseases, especially cancer. Our analysis show that CDR1as expression in human cancer is significantly associated with poor overall survival (hazard ratio [HR] = 2.50, 95% confidence interval [CI] = 2.06–3.04; p < 0.00001) and that high CDR1as expression is associated with the tumor node metastasis stage (odds ratio [OR] = 2.13, 95% CI = 1.63–2.78; p < 0.00001), and distant metastasis (OR = 3.50, 95% CI = 1.90–6.64; p < 0.00001). Furthermore, the results reveal the prognostic significance of CDR1as in neoplasms of the digestive system (HR = 1.69, 95% CI = 2.14–2.71; p < 0.001), colorectal cancer (HR = 1.34, 95% CI = 1.96–2.85; p < 0.001), and non-small cell lung cancer (HR = 2.40, 95% CI = 3.42–4.83; p = 0.008). In this study, we summarize in detail the latest research findings and demonstrate the function and regulatory mechanism of CDR1as in various cancer processes, and its potential as a biomarker for cancer prevention and prognosis.

The rational design of interfacial structures provides more opportunities to improve the performance of heterogeneous catalysts for water splitting. However, they still suffer from high oxygen and hydrogen evolution reaction (OER and HER) overpotentials and sluggish kinetics. Herein, a novel interfacial S-atom-regulated metallic Co and FeOOH heterostructure catalyst on Ni foam (FeOOH/S-Co/NF) is designed for alkaline water splitting with high performance. The FeOOH/S-Co/NF catalyst exhibits low overpotentials of 264 and 27 mV at 10 mA cm−2, and 294 and 108 mV at 100 mA cm−2 for OER and HER, respectively, with high stability. When serving as a bifunctional catalyst, only 1.576 V is required to drive 10 mA cm−2. In situ Raman spectroscopy and theoretical calculations validate that interfacial microenvironment regulation optimizes the adsorption of OER and HER intermediates and reduces the thermodynamic energy barrier of the OER reaction. This study provides a new strategy and insight for designing efficient metal-compound heterostructure electrolytic water catalysts. [ABSTRACT FROM AUTHOR]

Ferroelectrics with electrically switchable spontaneous polarizations can be used for information storage, where a low switching barrier is favorable to reduce the energy cost and enhance the speed for data writing. Meanwhile their robustness at working temperature should be ensured, which is a challenge for the designs of low‐barrier ferroelectrics. Here we review several types of ferroelectric mechanisms that may render both low switching barriers and room‐temperature robustness, which have been theoretically proposed in previous studies. (1) The prediction of sliding ferroelectricity with ultralow switching barriers has been experimentally confirmed in a series of van der Waals layers, which may enable convenient electrical control of various physical properties in 2D materials, like magnetic, photovoltaic, valleytronic and topological properties. (2) Hydrogen‐bonded ferroelectricity spontaneously formed by head‐to‐tail chains can be switched by proton‐transfer crossing a low barrier, and a mechanism of ultra‐high piezoelectricity utilizing the specific features of hydrogen bonding has been proposed. (3) High‐ionicity ferroelectricity induced by covalent‐like ionic bondings may entail high polarizations and low barriers during switching, which is attributed to the features of long‐range Coulomb interaction, and the long ion‐displacements crossing unitcell may give rise to unconventional ferroelectricity with quantized polarizations even in crystals of non‐ferroelectric point groups. Those low‐barrier ferroelectric mechanisms may bring in both new physics and technological advances, which are to be further explored. This article is categorized under:Structure and Mechanism > Computational Materials Science [ABSTRACT FROM AUTHOR]

Al–Si/Ti3SiC2 composites with (10–40 wt. %) Ti3SiC2 content have been successfully fabricated by the spark plasma sintering method. The mechanical properties and wear behaviors of Al–Si/Ti3SiC2 composites have been investigated. The results revealed that the compressive and tribological performance of the composites was enhanced by adding Ti3SiC2 particles. The compressive strength was increased from 473 to 563 MPa. The optimal friction coefficient was 0.35. [ABSTRACT FROM AUTHOR]

In recent years, room-temperature ferroelectricity has been experimentally confirmed in a series of two-dimensional (2D) materials. Theoretically, for isolated ferroelectricity in even lower dimensions such as 1D or 0D, the switching barriers may still ensure the room-temperature robustness for ultrahigh-density non-volatile memories, which has yet been scarcely explored. Here, we show ab initio designs of 0D/1D ferroelectrics/multiferroics based on functionalized transition-metal molecular sandwich nanowires (SNWs) with intriguing properties. Some functional groups such as —COOH will spontaneously form into robust threefold helical hydrogen-bonded chains around SNWs with considerable polarizations. Two modes of ferroelectric switching are revealed: when the ends of SNWs are not hydrogen-bonded, the polarizations can be reversed via ligand reorientation that will reform the hydrogen-bonded chains and alter their helicity; when both ends are hydrogen-bonded, the polarizations can be reversed via proton transfer without changing the helicity of chains. The combination of those two modes makes the system the smallest proton conductor with a moderate migration barrier, which is lower compared with many prevalent proton-conductors for higher mobility while still ensuring the robustness at ambient conditions. This desirable feature can be utilized for constructing nanoscale artificial ionic synapses that may enable neuromorphic computing. In such a design of synaptic transistors, the migration of protons through those chains can be controlled and continuously change the conductance of MXene-based post-neuron for nonvolatile multilevel resistance. The success of mimicking synaptic functions will make such designs promising in future high-density artificial neutral systems. [ABSTRACT FROM AUTHOR]

Seminaphthorhodafluor (SNARF) Schiff base (SNARF-SB) bridged periodic mesoporous organosilicas (SSPMOs) with "turn-on" fluorescence enhancement for sensing Cu2+ were synthesized via a template-directed co-condensation method. Small-angle x-ray scattering (SAXS) patterns, high resolution transmission electron microscope (HRTEM) images, and N2 adsorption–desorption isotherms indicated the presence of mesoporous structure in the SSPMOs. FT-IR spectra and 29Si MAS NMR data confirmed the successful incorporation of bridged organic groups in the framework of SSPMOs. The luminous properties that SSPMOs had a selective response to Cu2+ were investigated by UV–Vis absorption spectroscopy and fluorescence spectroscopy. The limit of detection (LOD) was 5.1 × 10–7 M and binding stoichiometry was determined 1:1 between SNARF-SB and Cu2+. The fluorescence enhancement of SSPMOs towards Cu2+ was induced by ring-opening of the spirolactam in SNARF-SB in framework of SSPMOs, which was confirmed by FT-IR spectra of SNARF-SB with Cu2+. Moreover, SSPMOs have improved fluorescence lifetimes compared with that of SNARF-SB. Therefore, SSPMOs can be a progressive chemical sensor for Cu2+ due to its high selectivity, recyclability, and stability. [ABSTRACT FROM AUTHOR]

Seminaphthorhodafluor (SNARF) Schiff base (SNARF-SB) bridged periodic mesoporous organosilicas (SSPMOs) with "turn-on" fluorescence enhancement for sensing Cu2+ were synthesized via a template-directed co-condensation method. Small-angle x-ray scattering (SAXS) patterns, high resolution transmission electron microscope (HRTEM) images, and N2 adsorption–desorption isotherms indicated the presence of mesoporous structure in the SSPMOs. FT-IR spectra and 29Si MAS NMR data confirmed the successful incorporation of bridged organic groups in the framework of SSPMOs. The luminous properties that SSPMOs had a selective response to Cu2+ were investigated by UV–Vis absorption spectroscopy and fluorescence spectroscopy. The limit of detection (LOD) was 5.1 × 10–7 M and binding stoichiometry was determined 1:1 between SNARF-SB and Cu2+. The fluorescence enhancement of SSPMOs towards Cu2+ was induced by ring-opening of the spirolactam in SNARF-SB in framework of SSPMOs, which was confirmed by FT-IR spectra of SNARF-SB with Cu2+. Moreover, SSPMOs have improved fluorescence lifetimes compared with that of SNARF-SB. Therefore, SSPMOs can be a progressive chemical sensor for Cu2+ due to its high selectivity, recyclability, and stability. [ABSTRACT FROM AUTHOR]

To reduce the over‐dependence on Pt, Pd‐based catalysts have become one of the most effective candidates for oxygen reduction reaction (ORR). In order to further accelerate the ORR kinetics and strengthen the catalytic performance of Pd catalysts, component optimization and morphology design have been adopted. Although great progress has been made, it is still difficult to obtain porous ultrathin nanosheets with excellent performance by a simple method. Here, ultrathin PdCuMo porous nanosheets (PdCuMo NSs) were successfully prepared. This structure possessed a large specific surface area with rich cavities and structural defects, significantly enhancing its ORR performance. In special, the mass activity of PdCuMo NSs was 1.46 A mg−1 at 0.90 V, which was 12.2, 8.6, and 2.7 times as high as that of Pd/C, Pt/C, and PdCuMo nanoparticles (PdCuMo NPs), respectively. In addition, it had an excellent ability to resist CO poisoning and exhibited remarkable long‐term stability. [ABSTRACT FROM AUTHOR]

Coronavirus Disease 2019 (COVID-19) has caused a pandemic globally since its outbreak in 2019. As an important port city with prosperous foreign trade, Shanghai has been under severe pressure to prevent the input of COVID-19. With this in mind, solid policies and measures have always been taken in Shanghai to control the input of COVID-19 strictly. In March 2022, the SARS-CoV-2 Omicron variant swept Shanghai, and then the home office order was rapidly carried out in most of the districts. This article focuses on quantifying the changes in concentrations of PM10 and PM2.5 in Shanghai after implementing the home office order and exploring the spatial-distribution characteristics and time trend of the impact of the home office order on airborne particulate matters (PMs) through an interrupted-time-series (ITS) analysis. This study found that PM10 and PM2.5 decreased by 31.40 μg/m3 (p = 0.028) and 10.33 μg/m3 (p = 0.276), respectively, with the fastest decrease speed in the first 10 days of the home office order. Meanwhile, the changes in PM concentrations in eastern areas such as Fengxian District and Chongming District are less than those in central and western areas of Shanghai. Therefore, it can be concluded that implementing the home office order for 10 days could effectively cut down PM concentrations, and the reduction values can be affected by spatial difference and time factor. [ABSTRACT FROM AUTHOR]

Metallic ultrathin nanosheets have drawn increasing attention due to their distinct properties and wide applications. Nonetheless, the successful preparation of metallic ultrathin nanosheets is still a huge challenge because metallic bonds have no direction and tend to form three-dimensional close-packed structures. Here, ultrathin curved PtPdMo nanosheets (UC-PtPdMo NSs) were obtained by controlling the anisotropic growth kinetics through the CO released from Mo-(CO)6. Meanwhile, different doses of PVP and CTAB could induce the formation of ultrathin porous PtPdMo NSs (UP-PtPdMo NSs) and ultrathin PtPdMo NSs (U-PtPdMo NSs). Among them, UC-PtPdMo NSs had the optimal catalytic activity for oxygen reduction reaction (ORR), and its specific and mass activities were 4.1 and 3.6 times as large as those of Pt/C. Moreover, it showed better stability than the other catalysts after 10k cycles. The strengthened catalytic properties might have resulted from the ultrathin structures and the electronic adjustment of Pt by Pd and Mo elements. [ABSTRACT FROM AUTHOR]

According to the model of sliding ferroelectricity we proposed in 2017, a type of vertical polarization switchable via interlayer sliding may exist in a series of two-dimensional van der Waals bilayers and multilayers. Such intriguing ferroelectricity has been recently experimentally confirmed in BN and WTe2 bilayer/multilayer systems. However, they are respectively insulators and metals with weak polarizations. Here, we search for a combination of high-mobility semiconductors and ferroelectricity with relatively high polarizations, and we note that MoSi2N4 monolayer has been recently fabricated to centimeter scale based on MoN2 monolayer (Science 2020, 369, 670). We show first-principles evidence of strong interlayer sliding ferroelectricity in high-mobility semiconducting MoA2N4 (A = Si or Ge) bilayers and multilayers. They possess tunable bandgaps within the desirable range for nanoelectronics, with the current highest polarizations in sliding ferroelectrics known to date due to strong interlayer van der Waals interactions. Such a successful combination of these properties may render the long-sought and efficient computing-in-memory possible. Their high polarizations induce strong Moiré potential and unique band alignments for exciton trapping in twisted MoA2N4 bilayer. The varying charge distribution of different stacking in MoN2/MoSi2N4 hetero-bilayer also gives rise to a high alternating voltage when used as a nanogenerator, suggesting promising potential for energy harvesting. [ABSTRACT FROM AUTHOR]

We propose a new approach to obtain ultra-high piezoelectric coefficients that can be infinitely large theoretically, where ferroelectrics with strain-sensitive Curie temperature are necessary. We show the first-principles plus Monte Carlo simulation evidence that many hydrogen-bonded ferroelectrics (e.g. organic PhMDA) can be ideal candidates, which are also flexible and lead-free. Owing to the specific features of hydrogen bonding, their proton hopping barrier will drastically increase with prolonged proton transfer distance, while their hydrogen-bonded network can be easily compressed or stretched due to softness of hydrogen bonds. Their barriers as well as the Curie temperature can be approximately doubled upon a tensile strain as low as 2%. Their Curie temperature can be tuned exactly to room temperature by fixing a strain in one direction, and in another direction, an unprecedented ultra-high piezoelectric coefficient of 2058 pC/N can be obtained. This value is even underestimated and can be greatly enhanced when applying a smaller strain. Aside from sensors, they can also be utilized for converting either mechanical or thermal energies into electrical energies due to high pyroelectric coefficients. [ABSTRACT FROM AUTHOR]

Aggregate breakdown and transportation caused by raindrops clogs soil pores and aggravates the formation of surface crusts. However, changes in soil pore microcharacteristics after raindrop impact are equivocal. In this research, we used synchrotron‐based X‐ray microcomputed tomography (SR‐μCT) and image processing techniques to quantitatively analyze the pore microcharacteristics of undisturbed soil and disturbed soil impacted by raindrop diameters of 2.67 mm (small), 3.39 mm (medium), and 4.05 mm (large). The results showed that the changes in the soil pore microcharacteristics were mainly caused by medium and large raindrops. Compared with the undisturbed soil, the total imaged porosity decreased by 5.91% after splashing by small raindrops and significantly (P <.05) decreased by 15.83 and 18.28% after medium and large raindrop splashing, respectively. The total volume of pores and the porosity of the large pores had the same decreasing trend as the total porosity. The porosity of the elongated pores decreased by 11.51 and 23.41% after medium and large raindrop splashing, respectively. The raindrop action clogged the soil pores. The clogging ratios caused by small, medium, and large raindrops were 1.06, 2.83, and 3.29%, respectively, and increased with raindrop diameter, rain intensity, and rainfall energy. Thus the increase in pore clogging and the decrease in macroporosity are the main reasons for the formation of surface crusts. [ABSTRACT FROM AUTHOR]