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The freshwater scarcity and sustainability of overexploited aquifers have been recognized as a big threat to global water security for human development. Consequently, much research has focused in the past on negative consequences of groundwater abstraction, but somewhat less has been documented about the impacts of adequate management practices to address water shortages. Here, using an integrated analysis of InSAR displacement data, groundwater, and geophysical modeling we show how combined management provisions and inter-basin water transfer project has affected the aquifer system in Taiyuan basin in North China. Following groundwater recovery, the alleviation of land subsidence was found with rates being reduced by up to ~70% in the period 2017–2020 with respect to the period 2007–2010. The increase in pore pressure caused by rising groundwater in Taiyuan city, north of the basin, turned four subsidence centers with rates exceeding 110 mm/yr in the 1980 to uplift centers with rates up to +25 mm/yr between 2017 and 2020. A simple linear elastic model for homogenous subsurface properties can explain InSAR-measured surface displacements well. In the central basin, we found a significant seasonal displacement with annual amplitude up to 43 mm (negative peak in autumn and positive peak in spring) related to the groundwater recharge and discharge due to agricultural pumping irrigation. Using cross-wavelet method, we showed a relatively short time lags (less than one month) between surface deformation and water level changes in the central basin, indicating the low-permeability clayey units have a limited influence in delaying the compaction of aquifer system. Quantifying the effects of adequate groundwater management measures and large-scale engineering approaches like inter-basin water transfer to recharge pumped aquifers provide insight for local governments and decision-makers to properly evaluate the impacts of their policy in recovering the sustainability and efficiency of aquifers in water-deficient basins.

This study aimed to address the status, role, and mechanism of sympathetic nerve infiltration in the progression of stomach adenocarcinoma (STAD).Sympathetic nerve and its neurotransmitter NE, β-ARs, and associated signaling molecules in the STAD tissues and the adjacent tissues from 46 STAD patients were examined using immunostaining, HPLC, and western blotting. The effects and mechanisms of β2-AR activation on the proliferation, migration and invasion of AGS and SGC-7901 gastric cancer (GC) cell lines were examined using CCK-8, transwell, and western blotting assays. Correlations between genes and STAD survival were analyzed using bioinformatics.Striking sympathetic nerve infiltration, elevations of NGF, TrkA, GAP43, TH, S100, NE, β2-AR, YKL-40, syndecan-1, MMP9, CD206, and CD31 were observed in the STAD tissues compared to the adjacent tissues. Activation of β2-AR in the two GC cell lines significantly amplified the expressions of NGF, YKL-40, MMP9, syndecan-1, p-STAT3 and p-ERK, and increased GC cell proliferation, migration and invasion. Bioinformatic analyses revealed positive correlations of NGF, β2-AR, syndecan-1, and macrophage infiltration, respectively, with low survival of STAD, of β2-AR respectively with STAT3, ERK1/2 (MAPK1/3), YKL-40, MMP9, and syndecan-1, and of YKL-40 with MMP9.Sympathetic nerves significantly infiltrated into human STAD tissues as a result of high NGF and TrkA expressions; elevated NE led to overactivation of β2-AR-STAT3/ERK-YKL-40 signaling pathway, and finally caused cancer cell growth and invasion, M2 macrophage infiltration, angiogenesis, matrix degradation and STAD metastasis and progression.

Surface plasmon polaritons (SPPs) and their counterparts at low frequency (i.e., spoof SPPs) have been attracting a lot of attention recently due to their potential application for routing information with high speeds and bandwidth. To further develop integrated plasmonics, a high-efficiency surface plasmon coupler is required for full elimination of the intrinsic scattering and reflection when exciting the highly confined plasmonic modes, but a solution to this challenge has remained elusive so far. To take on this challenge, here we propose a feasible spoof SPP coupler based on a transparent Huygens’ metasurface, which is able to realize more than 90% efficiency in near- and far-field experiments. To be specific, electrical and magnetic resonators are designed separately on both sides of the metasurface to satisfy the impedance-matching condition everywhere, leading to full conversion of plane wave propagation into surface wave propagation. Moreover, a well-optimized plasmonic metal which is able to support an eigen SPP is designed. This proposed high-efficiency spoof SPP coupler based on a Huygens’ metasurface may pave the way for the development of high-performance plasmonic devices.

Hypoxia/oxygen-sensing signally is closely associated with many tumor progressions, including osteosarcoma (OS). Previous research principally focused on the function of hypoxia-inducible factor (HIF)-1α and HIF-2α as the major hypoxia-associated transcription factors in OS, however, the role of HIF-3α has not been investigated. Our study found that HIF-3α was upregulated in OS tissues and cell lines. HIF-3α overexpression facilitated cell proliferation and invasion, and inhibited apoptosis, whereas HIF-3α knockdown showed the opposite results. Chromatin immunoprecipitation analysis revealed that lysine demethylase 3A (KDM3A) expression was transcriptionally activated by HIF-3α under hypoxia, and KDM3A occupied the SRY-box transcription factor 9 (SOX9) gene promoter region through H3 lysine 9 dimethylation (H3K9me2). Additionally, rescue results revealed that KDM3A or SOX9 overexpression reversed the effects of HIF-3α silence on cell functions. The Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway inhibitor cucurbitacin I suppressed the promotive effects of HIF-3α overexpression on cell proliferation, invasion and TAK2/STAT3 pathway. Finally, OS cell line MG-63 transfected with HIF-3α short hairpin RNA (HIF-3α shRNA) were subcutaneously injected into nude mice, and the results found that HIF-3α knockdown significantly inhibited the xenograft tumor growth of OS in vivo. In conclusion, this study reveals that HIF-3α promotes OS progression in vitro and in vivo by activating KDM3A-mediated SOX9 promoter demethylation, which may provide a potential therapeutic mechanism for OS.

Owing to the economical and practical solution synthesis and coating strategies, silver nanowires (AgNWs) have been considered as one of the most suitable alternative materials to replace commercial indium tin oxide (ITO) transparent electrodes. The primitive AgNW electrode cannot meet the requirements for preparing high performance optoelectronic devices due to its high contact resistance, large surface roughness and poor stability. Thus, various post-treatments for AgNW film optimization are needed before its actual applications, such as welding treatment to decrease contact resistance and passivation to increase film stability. This review investigates recent progress on the preparation and optimization of AgNWs. Moreover, some unique fabrication strategies to produce highly oriented AgNW films with unique anisotropic properties have also been carried out with detailed analysis. The representative devices based on the AgNW electrode have been summarized and discussed at the end of this review.

Summary Radial jet drilling (RJD) is an unconventional drilling technology that uses high-pressure liquid jet to drill multiple radial laterals. It is a cost-effective alternative for bypassing damage zones near the wellbore, restimulating the production of old wells, and developing unconventional reservoirs. However, because of the structure of the deflector and the diameter of the radial laterals, traditional well-trajectory measuring tools cannot be applied in RJD wells, which hinders the conduct of some significant operations. The unknown trajectory is a crucial limitation to further development and field application of RJD technology. In this paper, along with an introduction to RJD technology, a measuring system and a mini-tool are proposed for attitude measurement and motion-state recognition. With an extra tripping stage, the tool is tripped down to the bottom of the RJD laterals after the jet drilling is completed, and then tripped out at a constant speed. The measured data stored in memory media could be downloaded after the measurement. On the basis of navigation theory, a reckoning method was proposed to obtain the trajectory parameters by using the recorded data of the tool and the operational data of the coiled tubing (CT). After that, an experimental study was carried out to test the performance of the measuring tool and the reckoning method. As results of the experiments demonstrate, the average errors of the measured length, inclination, and azimuth are 3.94, 2.62, and 4.54%, respectively.

In the conventional fiber drawing process, the waveguide parameters (fiber core diameter, refractive index profile, numerical aperture) of the optical fiber are decided (with very limited perturbation range) once the optical and geometric properties of the preform are determined. In comparison, yttrium aluminosilicate (YAS) fibers prepared by “molten core method” (also termed as “melt-in-tube” method) reveal a unique fiber formation process. Although the previous works have shown that the element diffusion plays a significant role in the formation of YAS fiber, the description of this formation process is still vague and the properties of YAS fibers obtained by this method show low controllability in practice, which cannot be explained by elemental diffusion alone. Here, a new model for the formation mechanism of YAS fibers is proposed based on the experimental data, which involves the consideration of interfacial stress during the formation of YAS fibers. The relationship between the refractive index and the element distribution in the YAS fibers was studied. Structural simulation based on the molecular dynamics was also performed to demonstrate the formation mechanism of glassy YAS fiber core.

We report spontaneously formed random corrugations as an efficient light extraction strategy in flexible organic light-emitting devices (OLEDs). The corrugations with directional randomness and broad distribution are spontaneously formed on the modified surface of SU-8 elastic film due to the mismatch of thermal expansion coefficients between the surface and bulk of SU-8. The topographic parameters of the random corrugations are desirably tunable by simply adjusting the annealing temperatures. The flexible OLEDs based on the random-corrugated SU-8 substrate demonstrate the improved light extraction characteristics in broadband, corresponding to the enhancements of 34% in luminance and 15.09% in current efficiency without directionality and spectral changes. The corrugated OLEDs also show high flexibility and mechanical stability without dramatical performance falloff under bending, folding as well as twisting.

We report a highly flexible ultrathin Au grid with high mechanical robustness as transparent electrode for flexible organic light-emitting devices (OLEDs). The grids are introduced to an ultrathin Au film to improve its optical transmittance and mechanical performance. With the line width of 15 μm and the gap width of 30 μm, the optimal ultrathin Au grid presents a desirable transmittance of 88.7% at 550 nm and a sheet resistance of 36 Ω/sq. Owing to the reduced tensile stress by the ultrathin grid patterns, the flexible ultrathin Au grid exhibits extraordinary mechanical stability with maintained conductivity after 48 000 bending cycles under a bending radius of 1 mm. Flexible OLEDs with high flexibility and mechanical robustness have been obtained using the ultrathin Au grid as the transparent anode by maintaining 92% initial efficiency after 4200 bending cycles. Moreover, flexible OLEDs exhibit a significantly improved current efficiency in comparison to the devices based on the continuous Au or traditional ITO anode.

A micro/nano structure on the metallic electrode is necessary to outcouple power lost to surface-plasmon polaritons (SPPs) in organic light-emitting devices (OLEDs). However, a simple and efficient method to integrate the micro/nano pattern onto the surface of the metallic film is still a challenge. In this work, thermal nanoimprint lithography has been employed to directly imprint periodic corrugation onto an ultrathin metallic film. Both surface morphology and conductivity of corrugated metallic film have been improved by the imprinting process, which is important for its use as electrode in optoelectronic devices. The photons that trapped in SPP modes associated at the organic-cathode interface in the OLEDs have been efficiently extracted by using the periodically corrugated ultrathin metallic film as anode of the OLEDs. A 56% enhancement of current efficiency was achieved compared with the planar device. The corrugated ultrathin anode is further applied to flexible OLEDs, and improved light extraction efficiency has been obtained.

We propose a facile, scalable strategy to introduce spontaneously formed disordered wrinkles into organic light-emitting devices (OLEDs) to enhance light extraction and realize stretchability of the devices. The luminance and current efficiency of the wrinkled OLEDs are improved by 37% and 18%, respectively, compared to the planar device. Meanwhile, broadband light scattering induced by the disordered wrinkles results in angle-stable electroluminescent spectra at wide viewing angles for the wrinkled OLEDs. The disordered wrinkles enable the OLEDs to be stretchable and withstand hundreds of stretching–releasing cycles at strain between 0% and 5%. This study provides a simple method to realize stretchable OLEDs with high efficiency.

Reinforced concrete – steel plate composite shear walls (RCSPSW) have attracted great interests in the construction of tall buildings. From the perspective of life-cycle maintenance, the failure mode recognition is critical in determining the post-earthquake recovery strategies. This paper presents a comprehensive study on a wide range of existing experimental tests and develops a unique library of 17 parameters that affects RCSPSW’s failure modes. A total of 127 specimens are compiled and three types of failure modes are considered: flexure, shear and flexure-shear failure modes. Various machine learning (ML) techniques such as decision trees, random forests (RF),K-nearest neighbours and artificial neural network (ANN) are adopted to identify the failure mode of RCSPSW. RF and ANN algorithm show superior performance as compared to other ML approaches. In Particular, ANN model with one hidden layer and 10 neurons is sufficient for failure mode recognition of RCSPSW.

The pressure transient behavior of water injection well has been extensively investigated under single-phase flow conditions. However, when water is injected into formation, there are saturation gradients within the water flooded area. Additionally, water imbibition is essentially important for oil displacement in dual-porosity and dual-permeability (DPDP) reservoirs. In this work, a novel semianalytical two-phase flow DPDP well test model considering both saturation gradient and water imbibition has been developed. The model was solved by the Laplace transform finite difference method. Type curves were generated, and flow regimes were identified by the model. The model features and effect of parameters were analyzed. Results show that water imbibition reduces the advancing speed of water drive front in the fracture system and slows down the water cut raising rate and the expansion speed of the two-phase zone in the fracture system. Therefore, the fluid exchange between the fracture and matrix systems becomes more sufficient and more oil will be recovered from the DPDP reservoir. The shape of pressure curves is similar for the single-phase and two-phase flow DPDP model, but the position of the proposed model is above the curves of the single-phase model. Shape factor mainly influences the interporosity period of the pressure derivatives. Water imbibition has a major effect on the whole system radial flow period of the curves. The findings of this study can help for better understanding of the oil/water two-phase flow pressure transient behavior in DPDP reservoirs considering saturation gradients and water imbibition.

Located in the middle of Shanxi Province, northern China, Taiyuan basin is a dry and water-short region. This region is reaching alarming levels of aquifer depletion due to decades of groundwater overexploitation, which has caused severe land subsidence in the basin. The Wanjiazhai Water Diversion Project (WWDP) was designed to ease water scarcity by transporting water from the Yellow River to the Taiyuan basin through 452.4 km-long canals. By the end of 2018, the WWDP had supplied 2.87 billion m3 of water to Shanxi Province, which replenish the basin’s surface water body as well as the underground aquifer. The groundwater levels have continued to rise since 2003, with rising levels of more than 70 meters by 2018 in comparison with its low stand in 2000.In this study, we use 2007-2010 ENVISAT, ALOS-1 data, and 2017-2020 Sentinel-1 data to study the response of the basin’s aquifer to the groundwater rebound against the background of the water transfer project. We addressed the issue of tropospheric delay and its impact on the seasonal deformation by combing GACOS (Generic Atmospheric Correction Online Service) and a common-point stacking method. The accuracy improvement of deformation by this correction method was validated with measurements from seven continuous GPS stations in the basin. Groundwater rebound triggers ground uplift, which was identified in five areas by InSAR with a rate up to 25 mm/yr. The uplifting displacement time series are well correlated with groundwater level recovery. The land subsidence in the south of the basin continues but the rates decreased significantly in 2017-2020 detected from Sentinel-1 as compared to that in period 2007-2010 from ENVISAT and ALOS-1. All these uplifting signals and the decreasing rates of land subsidence found in Taiyuan city provide the indication that water management practices are successful in mitigating further subsidence.We found a significant seasonal displacement concentrated within the central region of the basin corresponding to the main irrigated areas in the Taiyuan basin. The maximum peak-to-peak amplitude is 43 mm observed from ENVISAT and decreases to 20 mm observed from Sentinel-1. The seasonal amplitudes change rapidly across faults, indicating that the fault is an effective barrier to across-fault fluid flow. To further quantify the causal relationships between water level and ground displacement, groundwater levels and ground displacement at three wells located near the area affected by significant seasonal land subsidence are analyzed by Cross Wavelet Transform (XWT) method. We found the time lags of about one month between land subsidence and the forcing groundwater level declines. Such a cross wavelet analysis with high spatial-temporal resolution therefore enables tracking the health of the aquifer system and highlights the system’s sustainability in aiding water resources allocation against the background of the water diversion project.

Precision medicine for gastric cancer (GC) is still an unsolved issue, because most available target drugs are not specifically designed for GC. Exploring novel signaling molecules with target value for GC is in urgent need. This study aimed to reveal that interleukin-2 receptor subunit gamma (IL2RG) is such a key molecule in human GC progression. GC tissues and paracancerous gastric tissues were collected from 7 patients (5 males and 2 females) during tumor radical excision surgery. These tissues were used to identify the differentially expressed genes (DEGs) with RNA-seq and serial bioinformatics analyses including Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, gene expression profiling interactive analysis (GEPIA), and survival analysis. RT-qPCR and western blotting were performed to compare the mRNA and protein expression levels of IL2RG between GC tissues and adjacent normal gastric tissues as well as between GC cell line SGC-7901 and normal gastric epithelial cell line GES-1. Results showed striking elevations of IL2RG both in the mRNA and protein levels in GC tissues and human gastric cancer SGC-7901 cell line compared, respectively, with the adjacent normal gastric tissues and normal GES-1 cells, and higher IL2RG expression was associated with lower survival. Analyses on the GSE29272 and GSE15459 datasets from Gene Expression Omnibus verified that IL2RG was highly expressed in GC patients and was associated with poor overall survival. In addition, molecular docking showed that a small molecule, resatorvid (TAK 242), might be an inhibitor of IL2RG. We conclude that IL2RG is overexpressed in advanced GC and is associated with low survival. IL2RG may serve as a biomarker of GC progression and poor prognosis.

Tight oil reservoirs tend to contain more natural fractures, and the presence of natural fractures leads to a greater stress sensitivity in tight oil reservoirs. It is a very challenging task to model the seepage in the volume fracturing horizontal wells considering the stress-sensitive effects. Based on the Laplace transform, Perturbation transform and Stefest numerical inversion, this paper establishes a horizontal well seepage model for volume fracturing in fractured stress-sensitive tight oil reservoirs. This model allows us to analyze and study the effect of stress sensitivity, fracture interference, dual media and complex fracture network on seepage flow in tight oil reservoirs. We apply the model to delineate the seepage stages of volume fracturing horizontal wells, it can be divided into seven seepage stages I wellbore storage flow, II surface flow stage, III transition flow, IV natural fracture system proposed radial flow, V interporosity flow, VI system proposed radial flow and VII stress-sensitive flow stage. Wellbore storage coefficient mainly affects the flow in the wellbore storage stage. The larger the wellbore storage coefficient is, the longer the duration of wellbore storage flow will be. The higher the skin coefficient is, the greater the pressure drop is. The storage capacity ratio has a greater influence on the flow before the occurrence of channeling flow, and the “groove” depth on the derivative curve of dimensionless pressure drop becomes shallower with the increase in storage capacity ratio. The higher the channeling coefficient is, the earlier the channeling occurs from the matrix system to the natural fracture system and the more leftwing the “groove” position is.

In this work, lead-free double perovskite Cs2BiAgBr6 film is fabricated and employed into resistive switching (RS) memory device with a metal/insulator/metal structure. The RS performances of the prepared device are examined both experimentally and theoretically. High-quality Cs2BiAgBr6 film is fabricated via a post-vacuum treatment and characterized systematically. In the prepared memory device, bipolar RS is observed with a high ON/OFF ratio, and the retention and endurance performances are measured. First-principles calculations based on the density functional theory reveal that the bromide vacancies (VBr) in Cs2BiAgBr6 render it metallic characteristics. Therefore, we propose that the migration of VBr under electrical fields formed and ruptured the conductive filament, leading to the RS behaviors of memory device.

Peer-to-peer energy trading among microgrids has many advantages, e.g., increasing the utilization of renewable energies, reducing the dependence on the main grid and reducing energy cost. In this paper, we investigate a peer-to-peer energy trading problem among microgrids under uncertainties. To be specific, each microgrid intends to maximize its own utility in a local peer-to-peer energy market. Due to the existence of uncertainties in renewable energy output and power demand of all microgrids, and temporally-coupled constraints related to energy storage devices, it is very challenging to develop an optimal energy trading policy for each microgrid. To achieve the above aim, we propose a multiagent deep deterministic policy gradient (MADDPG)-based energy trading algorithm, which can help to find the optimal policy for each microgrid without requiring the generation and load information of other microgrids. Moreover, blockchain is adopted to guarantee the integrity of energy transaction data. Simulation results show the effectiveness of the proposed algorithm in the aspect of reducing energy cost and ensuring the security of transaction data.

We report an improved light extraction in all-inorganic perovskite light-emitting devices (PeLEDs) by integrating a periodic corrugated nanostructure at the metallic cathode/organic interface. Nanoimprinting lithography was used to introduce the nanostructures onto the surface of the electron transport layer directly to avoid influencing the morphology and crystallinity of the perovskite film underneath. The trapped energy at the metallic electrode has been successfully outcoupled by the excitation of the surface plasma polariton (SPP) modes induced by the periodic corrugations. The luminance and current efficiency of the periodically corrugated PeLED exhibit enhancements of 42% and 28%, respectively, compared to those of the planar PeLED. The finite-difference time-domain simulation was used to confirm the efficient outcoupling of the SPP modes.

An ultrathin metal film with high transmittance and conductivity has been demonstrated to be a promising transparent electrode for organic light-emitting devices (OLEDs). However, mediocre surface morphology and continuity of evaporated metal films and the surface plasmon-polaritons (SPPs) energy loss between the metal electrode and organic layer still limit the external quantum efficiency (EQE) of OLEDs. Here, nanoimprint lithography has been directly applied on the ultrathin Au film with underlying uncured photopolymer to fabricate the nanopillared anode. Both the conductivity and transmittance of the nanopillared ultrathin Au film have been improved due to the improvement of continuity and surface smoothness. As we expected, the SPPs mode has been coupled into photons and further extracted from OLEDs by using the nanopillared Au film anode. Finally, 19.2% and 70.1% enhancement of current efficiency were achieved compared to the planar device with ultrathin Au anode and ITO anode, respectively.

The fracture toughness of shale is a basic parameter that can provide effective theoretical support for wellbore stability and hydraulic fracturing of a shale reservoir. Due to the composition and microstructure, there are many problems in evaluating the mechanical properties of shale in a macroscopic test. In this paper, the composition and pore distribution of shale were studied by X-ray diffraction and nuclear magnetic resonance. Scanning electron microscopy was used to characterize the pore structure. The setting of experimental parameters and the selection of the indenter were discussed. Micro-indentation technique was proposed and applied to fracture toughness analysis of shale. The results show that Berkovich indenter is more suitable for shale indentation test than Vickers indenter. Fracture toughness of shale indentation is obviously affected by surface roughness and indentation position. Fracture toughness of shale decreases slightly with the increase of the indentation load. The energy analysis result presents that the effect of cracking on the ratio of total/unloading work is minimal when there is no significant stripping on the shale surface. Compared with the experimental method, energy methods can obtain all the analysis parameters from a single indentation test. The results of comparative analysis with macroscopic experiments display that micro-indentation test can effectively predict the macroscopic fracture toughness of shale.

The debate on creep in primary consolidation is analysed with a power law model following an approach in which creep is considered as rate of loading. According to this approach, primary consolidation is one type of rate of loading. To verify this approach, two types of tests, standard oedometer test and oedometer test with drainage prevented, are conducted on three types of soils (two from NGES and the other from Port of Guangzhou). The result: creep exponents obtained from two kinds of tests agree well with each other. Moreover, the approach is further validated by tracking, for over 80 years, the data from settlement of the case history San Jacinto Monument, which is inconsistent with data calculated from the classical method. In the end, procedure of this approach, with which long term settlement is predicted, is illustrated, and this approach is compared with the classical method.

Enterovirus D68 (EV-D68) is an emerging viral pathogen belonging to the Enterovirus genus of the Picornaviridae family, which is a serious threat to human health and has resulted in significant economic losses. The EV-D68 genome encodes an RNA-dependent RNA polymerase (RdRp) 3Dpol, which is central for viral genome replication and considered as a promising target for specific antiviral therapeutics. In this study, we report the crystal structures of human EV-D68 RdRp in the apo state and in complex with the inhibitor NADPH, which was selected by using a structure-based virtual screening approach. The EV-D68-RdRp-NADPH complex is the first RdRp-inhibitor structure identified in the species Enterovirus D. The inhibitor NADPH occupies the RNA template binding channel of EV-D68 RdRp with a novel binding pocket. Additionally, residues involved in the NADPH binding pocket of EV-D68 RdRp are highly conserved in RdRps of enteroviruses. Therefore, the enzyme activity of three RdRps from EV-D68, poliovirus, and enterovirus A71 is shown to decrease when titrated with NADPH separately in vitro. Furthermore, we identified that NADPH plays a pivotal role as an RdRp inhibitor instead of a chain terminator during restriction of RNA-dependent RNA replication. In the future, derivatives of NADPH may pave the way for novel inhibitors of RdRp through compound modification, providing potential antiviral agents for treating enteroviral infection and related diseases.

Scatterings and transport in Weyl semimetals have caught growing attention in condensed matter physics, with observables including chiral zero modes and the associated magnetoresistance and chiral magnetic effects. Measurement of electrical conductance is usually performed in these studies, which, however, cannot resolve the momentum of electrons, preventing direct observation of the phase singularities in scattering matrix associated with Weyl point. Here we experimentally demonstrate a helical phase distribution in the angle (momentum) resolved scattering matrix of electromagnetic waves in a photonic Weyl metamaterial. It further leads to spiraling Fermi arcs in an air gap sandwiched between a Weyl metamaterial and a metal plate. Benefiting from the alignment-free feature of angular vortical reflection, our findings establish a new platform in manipulating optical angular momenta with photonic Weyl systems., Comment: 14 pages, 3 figures

Halide lead perovskites are considered as one of the most promising optoelectronic materials in decades, but the toxicity and bio-accumulation of lead retard the commercialization. Therefore, seeking suitable lead-free perovskites and their variants are of vital importance. In this work, all-inorganic zinc halide perovskite variant Cs2ZnCl4 crystals with Sb3+ doping are synthesized via hydrothermal method. Transparent millimeter-sized crystals exhibit bright red photoluminescence (PL) under room temperature (RT) on account of self-trapped exciton (STE) emission of Sb3+, from 3P1 to 1S0 states. Temperature-dependent PL and time-resolved PL exhibit bimodality and intensity variations, revealing that Jahn-Teller effect of 3P1 state results two energy minima, and thermal activation may contribute to the spectrum change. Further, DFT calculations are carried out and the influences of Sb3+ doping are revealed. A bandgap reduction is achieved via doping, and the band edges are localized at Sb3+. A combination of experimental and theoretical studies demonstrates well that the soft lattice structure and the 5s2 lone pairs of Sb are vital for the STE emission.

We report an ultrathin Au transparent electrode with the thickness of only 4.4 nm based on an S-1805/Ag hybrid nucleation layer and its application in flexible organic light-emitting devices (OLEDs) as the replacement of indium tin oxide (ITO) anode. The Volmer–Weber growth mode of the deposited Au film has been suppressed successfully by using the hybrid nucleation layer, in which the S-1805 acts as a substrate modification layer and 0.6 nm Ag acts as a seeding layer. The resulting ultrathin Au film with the thickness of 4.4 nm shows high transparency, high conductivity, and ultrasmooth surface. A 25% improvement in efficiency has been demonstrated for the OLEDs with ultrathin Au anodes compared to the ITO-based devices. The application of the high-performance ultrathin Au electrodes in OLEDs results in high flexibility and mechanical robustness with small performance variations after 2100 bending cycles with a 7.5 mm bending radius.

The settlement of San Jacinto Monument is a very valuable long-term monitoring data (over 80 years) for studying time-dependent behavior in geotechnical engineering. Because the large discrepancy between predicted data and measured data in previous publications with other methods applied, it is restudied with a power law model by the author. The concept of creep associated with rate of loading is introduced. To verify the viewpoint, two kinds of tests (i.e., 1D consolidation test and 1D compression test) on the clay from National Geotechnical Experimental Site (NGES) at Texas A&M University are conducted. The case of San Jacinto Monument is reanalyzed with the model and the predicted data by the model are in very good agreement with the actual data, which demonstrate that the proposed model is suitable and flexible for two types of time-dependent behavior, namely, consolidation and creep, in geotechnical engineering.

The crystal structure, band structure, density of states, Mulliken charge, bond population and optical properties for LiBi1-xMxO3 (M=V, Nb, and Ta) were investigated using hybrid density functional theory. It was found that LiBiO3 doped with V, Nb, and Ta presented distinctly stronger covalent interactions in M-O (M=V, Nb, and Ta) than Bi-O, thus resulting in mild distortion of the structure and facilitating the separation of photogenerated carriers. Furthermore, the hybridizations of Bi-6s, M-d (M=V, Nb, and Ta) and O-2p widened the valence and conduction bands, which promoted transmission of photogenerated carriers in the band edge and thus caused better photocatalytic performance.

The electronic properties of germanium monosulphide (GeS) monolayer under tensile strain were investigated using first-principles calculations. Our computations showed that the band gap of GeS monolayer was tuned from 1.96 to 2.72 eV via uniaxial and biaxial tensile strain in the range of 10%. Besides, two transitions involving indirect to direct and direct to indirect were triggered when GeS monolayer was applied 3.5 and 9% tensile strain in the zigzag direction, however this transition had not happened when the tensile strain was applied in the armchair and biaxial direction. The band gap variations of GeS monolayer with the tensile strain were explained using a bond nature mechanism based on the Heitler–London's exchange energy model. Moreover, upon applying external strain, the acoustic phonon limited carrier mobility of GeS monolayer had an enhancement with more than two orders of magnitude at 300 K, from 2.40 × 10 3 to 8.11 × 10 5 c m 2 V − 1 s − 1 . These findings show that strain engineering is an effective way to tune the electronic properties of GeS monolayer and to extend the applications of GeS monolayer in the field of electronics and optoelectronics.

Yang Li,1,2,* Yanhong Duo,1,3,* Jiangang Bi,1 Xiaowei Zeng,4 Lin Mei,4 Shiyun Bao,1 Lisheng He,5 Aijun Shan,2 Yue Zhang,1 Xiaofang Yu1 1Department of Hepatobiliary and Pancreas Surgery, Second Clinical Medical College of Jinan University, Shenzhen People’s Hospital, Shenzhen 518020, China; 2Department of Emergency, Second Clinical Medical College of Jinan University, Shenzhen People’s Hospital, Shenzhen 518020, China; 3Key Laboratory of Plant Cell Activities and Stress Adaptation, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, China; 4Division of Life and Health Sciences, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518020, China; 5Department of Pathology, Second Clinical Medical College of Jinan University, Shenzhen People’s Hospital, Shenzhen 518020, China *These authors contributed equally to this work Introduction: MicroRNA-155 (miR-155) is an oncogenic microRNA, which is upregulated in many human cancers including colorectal cancer (CRC). Overexpression of miR-155 has been found to regulate several cancer-related pathways, and therefore, targeting miR-155 may be an effective strategy for cancer therapy. However, effective and safe delivery of anti-miR-155 to tumors remains challenging for the clinical applications of anti-miR-155-based therapeutics.Methods: In this study, we explored the expression of miR-155 and the transcription factor nuclear factor kappa B (NF-κB) in CRC tissues and cell lines, and the possible relationship between miR-155 and NF-κB. We further report on anti-miR-155-loaded mesoporous silica nanoparticles (MSNs) modified with polymerized dopamine (PDA) and AS1411 aptamer (MSNs-anti-miR-155@PDA-Apt) for the targeted treatment of CRC.Results: Results showed that miR-155 is overexpressed in CRC tissues and cell lines, and there is a positive feedback loop between NF-κB and miR-155. Compared to the control groups, MSNs-anti-miR-155@PDA-Apt could efficiently downregulate miR-155 expression in SW480 cells and achieve significantly high targeting efficiency and enhanced therapeutic effects in both in vivo and in vitro experiments. Furthermore, inhibition of miR-155 by MSNs-anti-miR-155@PDA-Apt can enhance the sensitivity of SW480 to 5-fluorouracil chemotherapy.Conclusion: Thus, our results suggested that MSNs-anti-miR-155@PDA-Apt is a promising nanoformulation for CRC treatment. Keywords: miR-155, mesoporous silica nanoparticles, AS1411 aptamer, NF-κB, 5-fluorouracil

Fluorescent semiconducting conjugated polymer nanoparticles (CPNs) are promising candidates for enhanced luminescent devices and bioimaging. The key aspect of all fluorescent materials is their high radiative yield. Combination of CPNs with metal nanoparticles (MNPs) is one of the ways to increase their fluorescent yield. Most of such combinations are introduced in the forms of sophisticated core–shells and thin films or layers. Herein, we synthesized CPNs of poly[2-methoxy,5-(2′-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) and silver nanoparticles (AgNPs) in aqueous solution in the form of metal–polymer nanocomplexes (MPNCs), which are not only easily achievable but also show significantly enhanced optical absorption and luminescence properties. To synthesize MPNCs, AgNPs with different molar ratios were added to a colloidal solution of CPNs. The adsorption of AgNPs on the surfaces of the CPNs was confirmed by transmission electron microscopy and UV-VIS absorption spectroscopy. Fluorescence and optical absorption spectroscopies revealed a substantial increase in the optical absorption and photoluminescence (PL) intensity of the MPNCs. It was observed that at optimum concentrations of AgNPs and CPNs in the colloidal solution of MPNCs, the PL intensity is enhanced by ∼11 fold. The increase in PL intensity is attributed to the energy transfer from AgNPs to CPNs via near-field-coupling and electric field enhancement in the nanogaps present among the adsorbed AgNPs on the surfaces of the MPNCs, which is confirmed by finite difference time domain (FDTD) simulations. Since the MPNCs as well as their ingredients were prepared in aqueous solutions, we believe that such nanocomplexes could find use not only in enhanced fluorescent devices but also in therapeutics and diagnostics.

Lightweight and low-cost organic photovoltaics (OPVs) hold great promise as renewable energy sources. The most critical challenge in developing high-performance OPVs is the incomplete photon absorption due to the low diffusion length of the carrier in organic semiconductors. To date, various attempts have been carried out to improve light absorption in thin photoactive layer based on optical engineering strategies. Nanostructure-induced light harvesting in OPVs offers an attractive solution to realize high-performance OPVs, via the effects of antireflection, plasmonic scattering, surface plasmon polarization, localized surface plasmon resonance and optical cavity. In this review article, we summarize recent advances in nanostructure-induced light harvesting in OPVs and discuss various light-trapping strategies by incorporating nanostructures in OPVs and the fabrication processing of the micro-patterns with high resolution, large area, high yield and low cost.

We present the Rabi energy tuning effects in strong coupling effects between surface plasmon (SP) and exciton in Kretschmann-Raether configuration by varying excitonic layer thickness. Both experimental results and theoretical calculations indicate that the anticross like dispersion relation comes from the rapid change of permittivity near the exciton state and can be attributed to the trong coupling between SP and exciton. Our findings reveal that the excitonic layer plays a key role in the SP-exciton coupling. The increase of the excitonic layer will not only enlarge the Rabi splitting energy, but also cause the redshift of SP dispersion relation. Thus to fulfill the coupling condition, there is a critical thickness of the excitonic layer at specific incident angle (θinc

A flexible efficient top-emitting organic light-emitting device (TOLED) on an off-the-shelf silk substrate has been demonstrated by planarizing the silk substrate with photopolymer NOA63. The flexibility of the bare silk substrates was retained in the planarized silk substrates due to ductile characteristics of cured NOA63. The planarized silk substrate has shown superiority on surface morphology, which is beneficial to the performances of OLEDs. Their maximum luminance and current efficiency are 45545 ${\rm{cd/ m}}^{2}$ and 37.7 cd/A, respectively. Moreover, our devices show not only high luminance and efficiency but also high flexibility and mechanical robustness. Emission of operating devices is uniform and free of defects under a very small bending radius and the luminance and efficiency do not deteriorate obviously after repeated bending. TOLEDs on silk substrate are a potential alternative to wearable displays.

Epithelioid angiomyolipoma (EAML) is a rare variant of angiomyolipoma (AML). Previous studies have demonstrated that epithelial (E-)cadherin is expressed in two subtypes of AML, EAML and triphasic AML; however, the expression pattern of E-cadherin remains unclear. In the present study, a preliminary case-control study was conducted to determine the expression pattern of E-cadherin between EAML and triphasic AML, the control, focusing on the subcellular localization and expression category of E-cadherin. No significant difference was identified in the age, sex, history of tuberous sclerosis, smoking and alcohol consumption between the two groups (P>0.05). In EAML, 9 patients were categorized as exhibiting a low risk of malignant behavior and the other two were categorized as exhibiting an intermediate or high risk of malignant behavior. The proportion of cases expressing E-cadherin, human melanoma black-45 (HMB45), melanoma antigen recognized by T cells 1 (Mart1/Melan A), smooth muscle actin and progesterone receptor were 95.5 (21/22), 95.5 (21/22), 86.4 (19/22), 77.3 (17/22) and 86.4% (19/22), respectively. E-cadherin was identified to be localized, using staining techniques, in the cell membrane and/or cytoplasm. The subcellular localization of E-cadherin was significantly different between EAML and triphasic AML; the majority of EAML cases revealed membranous and cytoplasmic staining, whereas triphasic AML cases demonstrated cytoplasmic staining (P=0.0093). The expression of E-cadherin may be positively associated with HMB45 (P=0.0044) and Mart1/Melan A (P=0.0049). The results of the present study identified that the subcellular localization of E-cadherin may be different between EAML and the control group of triphasic AML. Additionally, E-cadherin and melanocytic markers may be co-expressed in distinct subtypes of AML. A follow-up study with a large sample size to validate the results of the present study, followed by a mechanistic study based on cell lines to determine any significance, are warranted.

Objective: To explore the differences in the effect of peroral traction-assisted endoscopic submucosal dissection (ESD) and traditional ESD for the treatment of early gastric cancer and precancerous lesions. Methods: 112 patients with early gastric cancer and precancerous lesions treated in our hospital between May 2013 and May 2016 were collected and divided into control group and observation group according to the random number table (n=56). Observation group of patients received peroral traction-assisted ESD, and the control group of patients only received traditional ESD. The intraoperative dissected lesion diameter, mean operation time and intraoperative blood loss of two groups of patients were recorded, enzyme-linked immunosorbent assay was used to detect serum inflammatory factor levels, and RIA was used to detect serum stress hormone levels. Results: Dissected lesion diameter of observation group was greater than that of control group (P

Liquid lithium is often used as a coating material in fusion reaction chambers, where it is under constant bombardment from high speed neutrons and protons. However, numerous fundamental questions are unanswered, for example whether a single proton impact can cause Li atom sputtering, and what is the electron excitation energy profile after a collision particularly for extremely high energy projectiles. Herein, we use a real-time dependent density functional method to study these questions for proton energies in the range of 30 eV to 1 MeV. The calculated stopping power agrees well with experiment, and it is found that the stopping power cannot be described by the single electron exciting spectrum based on the adiabatic eigen energies, and Li atom sputtering is not observed within our simulation time.

The bacterium Pseudomonas species sp. AP–3 is one of several microorganisms that are capable of using 2-aminophenol as its sole source of carbon, nitrogen and energy. Several 2-aminophenol-metabolizing enzymes have pivotal roles in the biodegradation of aniline and its derivatives as environmental pollutants in Pseudomonas. The bacterium Pseudomonas sp. AP–3 recruits a unique 2-aminomuconate deaminase (AmnE) to hydrolyze 2-aminomuconate to 4-oxalocrotonate, and releases ammonia in the modified meta-cleavage pathway by forming various compounds—including acetaldehyde, pyruvic acid, acetyl-CoA, and succinate—that may enter the Krebs cycle. AmnE also belongs to the YjgF/YER057c/UK114 family (also known as the Rid family), which is conserved in all domains of life and prefers structurally homotrimeric forms with diverse functional purposes. To study the mechanism of the modified meta-cleavage pathway in Pseudomonas sp. AP–3, we determined the first crystal structure of AmnE from Pseudomonas sp. AP–3 at 1.75 Å. AmnE forms a unique homohexamer instead of a trimer which is normally adopted by the members of YjgF/YER057c/UK114 family. Based on the structure of the AmnE hexamer, we observed a hydrophobic base composed of six Lp3 loops (residues 122–131) in each of the AmnE protomers that have pivotal roles in the assembly of the hexamer. Eighteen hydrogen bonds formed by the residues Met96, Pro126, and Arg56, which surround the hydrophobic base, allowed the combination of the two trimers into a stable hexamer. The single mutant of AmnE R56A lost the ability to maintain the hexameric conformation, and revealed that the hydrogen bonds between residues Arg56 and Met96 have pivotal roles in the AmnE hexameric assembly.