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Inhomogeneous broadening in disordered crystals has been widely recognized as a successful approach to enhance the spectral bandwidth of rare earth ions in optical spectra, and the Yb3+-doped mixed laser crystals are known as ultrafast pulse materials and have emerged as a hotspot recently. In this study, mixed sodium gadolinium/lanthanum double molybdate disordered laser crystals NaGd(1–x)La(x)(MoO4)2with x= 0.3, 0.5, and 0.9 were grown by the Czochralski (Cz) method. The structure of as-grown crystals was investigated by XRD, SEM, FT-IR, and Raman experiments. The spectroscopic properties, including absorption, emission, and fluorescence decay characteristics, were investigated thoroughly. The NaGd0.5La0.5(MoO4)2(NGLM) composite crystal exhibited an exceptionally broad absorption which reaches 70 nm (fwhm) at 980 nm, exceeding those of NaGd(MoO4)2(NGM) and NaLa(MoO4)2(NLM). Additionally, the electronic structures (band structure and density of states) of NGM, NGLM, and NLM were determined from the first-principles method combined with the PBE function. The calculations of defect formation energies under O-poor and O-rich conditions demonstrate that the +2 defects are easily generated in the undoped NGM crystal prepared under reducing atmospheres, and the calculation of absorption properties reveals that the black color of NGM without annealing is mainly attributed to intraband transitions between defect induction states and VBM or CBM. Moreover, the lifetimes of excited energy level 2F5/2of Yb3+were examined under different experimental environments to obtain the intrinsic radiative lifetime, and the emission cross section was calculated as 2.25 × 10–20cm2at 1016 nm. The features of the Yb3+:NaGd(1–x)La(x)(MoO4)2crystal indicate the potential applications for ultrafast and broad tunable laser through slight regulation of the composite engineering strategy.

Inorganic nanomaterials such as graphene, black phosphorus, and transition metal dichalcogenides have attracted great interest in developing optoelectronic devices due to their efficient conversion between light and electric signals. However, the zero band gap nature, the unstable chemical properties, and the low electron mobility constrained their wide applications. Bismuth oxyselenide (Bi2O2Se) is gradually showing great research significance in the optoelectronic field. Here, we develop a bismuth oxyselenide/p-silicon (Bi2O2Se/p-Si) heterojunction and design a self-powered and broadband Bi2O2Se/p-Si heterojunction photodetector with an ultrafast response (2.6 μs) and low dark current (10–10A without gate voltage regulation). It possesses a remarkable detectivity of 4.43 × 1012cm Hz1/2W–1and a self-powered photoresponse characteristic at 365–1550 nm (ultraviolet-near-infrared). Meanwhile, the Bi2O2Se/p-Si heterojunction photodetector also shows high stability and repeatability. It is expected that the proposed Bi2O2Se/p-Si heterojunction photodetector will expand the applications of Bi2O2Se in practical integrated circuits in the field of material science, energy development, optical imaging, biomedicine, and other applications.

Genotoxins cause nascent strand degradation (NSD) and fork reversal during DNA replication. NSD and fork reversal are crucial for genome stability and are exploited by chemotherapeutic approaches. However, it is unclear how NSD and fork reversal are triggered. Additionally, the fate of the replicative helicase during these processes is unknown. We developed a biochemical approach to study synchronous, localized NSD and fork reversal using Xenopusegg extracts and validated this approach with experiments in human cells. We show that replication fork uncoupling stimulates NSD of both nascent strands and progressive conversion of uncoupled forks to reversed forks. Notably, the replicative helicase remains bound during NSD and fork reversal. Unexpectedly, NSD occurs before and after fork reversal, indicating that multiple degradation steps take place. Overall, our data show that uncoupling causes NSD and fork reversal and elucidate key events that precede fork reversal.

The global outbreaks of deadly infectious diseases caused by pathogenic microorganisms have threatened public health worldwide and significantly motivated scientists to satisfy an urgent need for a rapid and accurate detection of pathogens. Traditionally, the culture-based technique is considered as the gold standard for pathogen detection, yet it has a long turnaround time due to the overnight culturing and pathogen isolation. Alternatively, nucleic acid amplification tests provide a relatively shorter turnaround time to identify whether pathogens exist in individuals with high sensitivity and high specificity. In most cases, nucleic acid amplification tests undergo three steps: sample preparation, nucleic acid amplification, and signal transduction. Despite the explosive advancement in nucleic acid amplification and signal transduction technologies, the complex and labor-intensive sample preparation steps remain a bottleneck to create a transformative integrated point-of-care (POC) molecular diagnostic device. Researchers have attempted to simplify and integrate the sample preparations for nucleic acid-based molecular diagnostic devices with innovative progress in integration strategies, engineered materials, reagent storages, and fluid actuation. Therefore, understanding the know-how and obtaining truthful knowledge of existing integrated POC molecular diagnostic devices comprising sample preparations, nucleic acid amplification, and signal transduction can generate innovative solutions to achieve personalized precision medicine and improve global health.

Studies on wheel flatness and polygonal wear have demonstrated that wheel defects cause severe impact forces at the wheel–rail interfaces. This study investigated the dynamic contact mechanical behaviour of high–speed train transmission gears when subjected to wheel defects. First, a train-track coupling dynamics model was established, considering the localized contact characteristics of transmission gears. This model was developed using the slice method and the Hertz contact model, exploring the spatial coupling effects between the gear contact interface and the train–track interface. Subsequently, the dynamic model was employed to extract essential contact mechanical parameters of the transmission gear under the influence of wheel defects, including gear meshing load, gear contact stress, and sliding velocity. Furthermore, an analysis was conducted to uncover and elucidate the mechanism by which wheel flatness and polygonal wear impact the dynamic contact behaviour of the transmission gear. This study underscores the importance of considering wheel defects when assessing the contact fatigue and wear performance of high-speed train transmission gears.

In this work, a series of self-activated KYb(MoO4)2phosphors with various xat% Er3+doping concentrations (x = 0.5, 1, 3, 5, 8, 10, 15) was synthesized by the solid-state reaction method. The phase structure of the as-prepared samples was analyzed by X-ray diffraction (XRD), XRD Rietveld refinement and Fourier transform infrared (FT-IR) spectroscopy. The as-prepared samples retain the orthorhombic structure with space group of Pbcneven Er3+doping concentration up to 15 at%. High-purity upconversion (UC) green emission with green to red intensity ratio of 55 is observed from the as-prepared samples upon the excitation of 980 nm semiconductor laser and the optimum doping concentration of Er3+ions in the self-activated KYb(MoO4)2host is revealed as 3 at%. The strong green UC emission is confirmed as a two-photon process based on the power-dependent UC spectra. In addition, the fluorescence intensity ratios (FIRs) of the two thermally-coupled energy levels, namely 2H11/2and 4S3/2, of Er3+ions were investigated in the temperature region 300–570 K to evaluate the optical temperature sensor behavior of the sample. The maximum relative sensitivity (SR) is determined to be 0.0069 K−1 at 300 K and the absolute sensitivity (SA) is determined to be 0.0126 K−1 at 300 K. The SAof self-activated KYb(MoO4)2:Er3+is almost twice that of traditional KY(MoO4)2:Er3+/Yb3+codoping phosphor. The results demonstrate that Er3+ions doped self-activated KYb(MoO4)2phosphor has promising application in visible display, trademark security and optical temperature sensors.

Soap bubbles exhibit abundant fascinating phenomena throughout the entire life of evolution with different fundamental physics governing them. Nevertheless, the complicated dynamics of small objects in soap films are still unrevealed. Here, we report the first observation of spontaneous particle ordering in a complicated galaxy of soap films without any external energy. The balance of interfacial tension at two liquid–gas interfaces is theoretically predicted to govern belted wetted particles (BWPs) traveling along a specified path spontaneously. Such spontaneous particle path-finding is found to depend on the particle size and hydrophilic properties. Spontaneous particle sorting is directly realized via these discrete and distinctive paths for different particles. The deformation of the soap membrane facilitates 1D/2D particle organization along the path. This observation represents the discovery of a new spontaneous order phenomenon in soap film systems and provides a new energy-free approach for particle separation and soft colloidal crystal assembly.

•We found a significant decrease in plasma miR-148a expression in HCC patients.•AUROC analysis confirmed diagnostic of miR-148a in the detection of HCC.•Plasma miR-148a is a potential non-invasive biomarker for HCC screening.•Detection of miR-148a might be a complementary approach to AFP for predicting HCC occurrence.

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The current backfilling coal mining methods still have many limitations, such as lack of filling time and filling space and poor coordination between filling time and filling space. On the basis, this paper proposed the Wongawilli roadway backfilling coal mining method (WRBCM). As a pattern of 'backfilling while mining', WRBCM gives fully play to the advantages of the Wongawilli mining method and the backfilling mining method. The research results have been put into practice in Wangtaipu coal mine. As the recovery ratio of coal resources in the panel reached 96.8%, the values of surface deformation were smaller than the indicators for building damage grade I in China. WRBCM also implements the safe and efficient coal mining deposited under 'buildings, railways and water bodies'. [Received: June 20, 2016; Accepted: January 28, 2017]

To optimise ground supporting and mitigate ground instability, a proper understanding of the ground conditions is critical. The concept of monitoring drilling parameters of a bolter for ground characterisation, which refers to identifying geological features included locations of joints and strengths of rock layers, has been studied in the past few decades. Several intelligent drilling units have been developed for joint detection but have limited capabilities. For instance, the existing systems fail to discriminate joints with the aperture of less than 3.175 mm and tend to generate false alarms. The objective of this research was to develop more efficient and sensitive detection programs for joint detection. To achieve this objective, a series of full-scale drilling tests with various simulated joint conditions have been conducted, and new detection programs have been proposed based on pattern recognition algorithms. Moreover, wavelet analysis has been applied to pre-process data to further promote detection programs. [Received: July 15, 2017; Accepted: November 18, 2017]

In designing bioassay systems for low-abundance biomolecule detection, most research focuses on improving transduction mechanisms while ignoring the intrinsically fundamental limitations in solution: mass transfer and binding affinity. We demonstrate enhanced biomolecular surface binding using an acoustic nano-electromechanical system (NEMS) resonator, as an on-chip biomolecular concentrator which breaks both mass transfer and binding affinity limitations. As a result, a concentration factor of 105has been obtained for various biomolecules. The resultantly enhanced surface binding between probes on the absorption surface and analytes in solution enables us to lower the limit of detection for representative proteins. We also integrated the biomolecular concentrator into an optoelectronic bioassay platform to demonstrate delivery of proteins from buffer/serum to the absorption surface. Since the manufacture of the resonator is CMOS-compatible, we expect it to be readily applied to further analysis of biomolecular interactions in molecular diagnostics.

As a fatal clinical syndrome, acute liver failure (ALF) is characterized by overwhelming liver inflammation and hepatic cell death. Finding new therapeutic methods has been a challenge in ALF research. VX-765 is a known pyroptosis inhibitor and has been reported to prevent damage in a variety of diseases by reducing inflammation. However, the role of VX-765 in ALF is still unclear.

A Nd-doped GdNbO4single crystals have been grown successfully using the Czochralski technique. The chemical etching method was employed to study the defects in the structural morphology of Nd:GdNbO4crystal with phosphoric acid etchant. Mechanical properties (such as hardness, yield strength, fracture toughness, and brittle index) of the as-grown crystal were systematically estimated on the basis of the Vickers hardness test for the first time. The transmission spectrum of Nd: GdNbO4was measured in the wavelength range of 320–2400 nm at room temperature, and the absorption peaks were assigned. Results hold great significance for further research on Nd:GdNbO4.

Roof and rib instability is an important issue in underground mining. To optimize ground support design, enhance ground stability, and reduce the possibility of roof or rib failure with minimal use of artificial ground support, it is essential to have an accurate understanding of ground conditions. This includes the location of voids, cracks, and discontinuities, as well as information about the different strata in the immediate roof. This paper briefly introduces ongoing research on void detection by using the roof bolter feed and rotation pressure. The goal of this project is to improve the sensitivity of detection programs to locate smaller joints and reduce the number of false alarms. This paper presents a brief review of the testing procedures, data analysis, logic, and algorithms used for void detection. In addition, this paper discusses the results of preliminary laboratory tests and statistical analysis of the data from these two drilling parameters used for void detection.

The use of inhomogeneous broadening in composite disordered crystals has been widely recognized as a successful approach to enhancing the spectral bandwidth of rare-earth ions in optical spectra. In this study, composite disordered laser crystals of rare-earth alkali metal double molybdate/tungstate, doped with 2 atom % Nd3+and represented by the general formula Nd:NaGd(MoxW1–xO4)2(x= 0.5, 0.7 and 0.9), were grown using the Czochralski method. The crystal structure of the disordered laser crystals was determined to be of the tetragonal phase with a space group of I41/a, as confirmed through X-ray diffraction (XRD) and Rietveld refinement analyses. The spectroscopic properties of the disordered laser crystal, encompassing absorption, emission, and fluorescence decay characteristics were investigated. The (MoO4)1.0(WO4)1.0composite crystal exhibited an exceptionally broad absorption bandwidth, with a full width at half-maximum (FWHM) of 21 at 808 nm, approximately 10 times wider than that of the well-known Nd:YAG crystal. Moreover, the composite crystal demonstrated the generation of a continuous-wave 1.06 μm laser, which was further frequency-doubled to produce a 532 nm laser. Additionally, the passively Q-switched laser behavior of the composite crystal at 1.06 μm was explored, utilizing tungsten disulfide as a saturable absorber. In summary, the double molybdate/tungstate composite disordered crystal exhibits advantageous characteristics, such as a low melting point (approximately 1200 °C), stable physical–chemical properties, and remarkable spectroscopic properties. These features highlight the potential applications of these composite crystals in all solid-state lasers. High-quality Nd-doped double molybdate/tungstate composite disordered laser crystals were grown by the Czochralski method. By implementing a composite engineering strategy, an exceptionally inhomogeneous spectral broadening with an fwhm of up to 21 at 808 nm was achieved.

Passively Q-switched mode-locking performance of Nd:GdTaO_4 crystal using molybdenum disulfide (MoS_2) as a saturable absorber at 1066 nm was demonstrated for the first time. The MoS_2 saturable absorber was prepared simply by transferring the MoS_2 suspension onto a quartz substrate. By inserting the MoS_2 saturable absorber into the Nd:GdTaO_4 laser, stable Q-switched modelocked operation can be achieved. At the pump power of 4 W, the maximum average output power of 0.156 W was obtained with the optical conversion efficiency of 3.9%.

Building Information Model (BIM) is used to share and exchange information between different applications for considerable processes of Architecture, Engineering and Construction (AEC) projects, and it is the key technology to manage information throughout the entire lifecycle of a building, solve the problem of information silo and improve the productivity of AEC project. This paper proposes a new method to extend the BIM technology, which makes it possible to integrate durability factors into design, durability analysis and residual life of building structures prediction. Based on the combination of the national durability code and achievements of RC durability study, a 3D Visualized RC Structure Durability Analysis is developed, which is verified to be capable of improving lifecycle management of AEC projects, upgrading durability level and optimizing the lifecycle cost structure of building projects by a case study.

Building Information Modelling (BIM) creates a way for all parties to share, exchange, and manage building information throughout the lifecycle of the building. On the other hand, radio frequency identification technology (RFID) has become one of the key technologies for automatic data collection and information storage. RFID can store building lifecycle information and context-aware information in a distributed database, so it can be considered as a component of the building information model. Therefore a standardized definition of the RFID components in the BIM is required. This paper proposes a standard method for adding RFID data definitions to BIM, and maps RFID data to related items in the BIM database. This study also defines the relationship between RFID tags and building components, and proposes the use of predefined relationships. The method of associating BIM data and RFID data can automatically select data related to RFID tag data by the relationship defined in BIM. Finally, the technical feasibility of the proposed method is proved by actual case test in the existing BIM software.

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Recent research indicates that performance and design of a liquid feed direct methanol fuel cell (DMFC) is controlled not only by electrochemical kinetics and methanol crossover but also by water transport and by their complex interactions in the design regime for portable electronics applications. In this paper, a three-dimensional (3D), two-phase model is presented for DMFCs, in particular considering water transport and treating the catalyst layer explicitly as a component rather than an interface without thickness. Other features of the model are similar to an earlier version published in 2003. The DMFC model is based on the multiphase mixture formulation and encompasses all components in a DMFC using a single computational domain. A flow solver, Fluent, is employed to simultaneously solve flow, species, and charge-transport equations. Numerical simulations in 3D are carried out to explore mass transport phenomena occurring in DMFCs for portable applications as well as to reveal an interplay between the local current density and methanol crossover rate. Numerical results also indicate that the anode flow field design and methanol feeding concentration are two key parameters for optimal cell performance.