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Vacancy-ordered perovskites A2M4+X6have shown potential in luminescence and photocatalytic applications, while limited research on them for solar cells exists. Previous studies have demonstrated that Cs2TiI6and Cs2TiBr6possess good stability and high optical absorption coefficients in the visible light range but have undesirable bandgap characteristics. In response to the shortcoming, we investigated the bandgap properties of Cs2TiIxBr6–xand further conducted a comprehensive analysis of the intrinsic defect properties and structural stability of Cs2TiIBr5and Cs2TiI2Br4. We find that as-yet-unsynthesized Cs2TiIBr5has a direct bandgap of 1.39 eV. Additionally, our results reveal that Cs2TiIBr5is thermodynamically stable and exhibits good defect tolerance. Notably, Cs2TiIBr5is expected to exhibit n-type conductivity with a considerable concentration of charge carriers under Ti-rich/Cs-rich/I-poor chemical potential conditions. Overall, our findings provide valuable theoretical insights that facilitate the experimental synthesis of new vacancy-ordered perovskites.

2-Fluorobenzofurans are the backbone structures of many drug molecules and have many potential therapeutic bioactivities. Despite the potential applications in medicinal chemistry, practical and efficient synthetic methods for the construction of 2-fluorobenzofuran are very limited. Herein, we report an efficient and general method for the construction of 2-fluorobenzofurans. Contrary to the previous functionalizations of the existing backbone of benzofuran, our strategy directly constructs benzofuran scaffolds alongside the incorporation of fluorine atom on C2 position in a formal [4 + 1] cyclization from readily accessible ortho-vinylphenols and difluorocarbene. In our strategy, ClCF2H decomposes into difluorocarbene in the presence of base, which is further captured by the oxygen anion from the hydroxy group in ortho-hydroxychalcones; subsequent intramolecular Michael addition to the α, β-unsaturated system leads to 2,2-difluorohydrobenzofurans, and further fluorine elimination renders 2-fluorobenzofurans by forming one C–O bond and one C–C double bond. Of note, various complex 2,2-difluorohydrobenzofurans and 2-fluorobenzofurans could be readily accessed through our protocol via the late-stage elaborations.

Herein, we report a versatile reaction platform for tracelessly cleavable cysteine-selective peptide/protein modification. This platform offers highly tunable and predictable conjugation and cleavage by rationally estimating the electron effect on the nucleophilic halopyridiniums. Cleavable peptide stapling, antibody conjugation, enzyme masking/de-masking, and proteome labeling were achieved based on this facile pyridinium-thiol-exchange protocol.

The benchmark advanced oxidation technology (AOT) that uses UV/H2O2integrated with hypochlorous species exhibits great potential in removing micropollutants and enhancing wastewater treatability for reclamation purposes. Although efforts have been made to study the reactions of H2O2with hypochlorous species, there exist great discrepancies in the order of reaction kinetics, the rate constants, and the molecule-level mechanisms. This results in an excessive use of hypochlorous reagents and system underperformance during treatment processes. Herein, the titled reaction was investigated systematically through complementary experimental and theoretical approaches. Stopped-flow spectroscopic measurements revealed a combination of bi- and trimolecular reaction kinetics. The bimolecular pathway dominates at low H2O2concentrations, while the trimolecular pathway dominates at high H2O2concentrations. Both reactions were simulated using direct dynamics trajectories, and the pathways identified in the trajectories were further validated by high-level quantum chemistry calculations. The theoretical results not only supported the spectroscopic data but also elucidated the molecule-level mechanisms and helped to address the origin of the discrepancies. In addition, the impact of the environmental matrix was evaluated by using two waters with discrete characteristics, namely municipal wastewater and ammonium-rich wastewater. Municipal wastewater had a negligible matrix effect on the reaction kinetics of H2O2and the hypochlorous species, making it a highly suitable candidate for this integration technique. The obtained in-depth reaction mechanistic insights will enable the development of a viable and economical technology for safe water reuse.

The swift proliferation of edge intelligence and ubiquitous data generation have heightened privacy into a pressing societal need. State-of-the-art reversible privacy protection requires significant hardware resources at the edge with distinct architecture for sensors and security, leading to a rise in hardware overhead and expanded attack surfaces. To address these challenges, we propose a time-domain mixed-signal (TD-MS) circuit architecture facilitating in-situ privacy (ISP) with hardware-secured data reversibility. The proposed TD-MS ISP unites data acquisition, data conversion, key generation, and protection while providing authorized device-specific unclonable data recovery for forensic purposes. At the system level, we demonstrate the attack resilience and privacy-preserving computation performance by implementing a custom embedded system applied to real-world surveillance scenarios. At the circuit level, we showcase custom TD-MS circuits, evaluating their energy and area efficiency against a digital baseline implemented in 65nm technology. With full-stack SPICE simulations for both the baseline digital and proposed TD-MS circuits, we measured a $670\times $ energy/frame savings against the embedded system, $3\times $ area reduction and $3.2\times $ energy TD-MS gains over digital.

In this paper, we propose a novel vehicle positioning method for commodity multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) WIFI systems in indoor parking lots. To address the limitation of the small number of WIFI antennas, the proposed method first utilizes signal model rearrangement techniques, in which the abundant carrier frequency resources of WIFI are expanded into space resources. Then a rearranged off-grid sparse Bayesian learning (ROG-SBL) algorithm is developed for parameters estimation to achieve vehicle positioning. Specifically, by resorting to the Bayesian inference and Newton method, the position-related parameters are estimated iteratively by fitting the channel state information (CSI) measurement model, and thus the vehicle positioning is realized according to the geometric relationship. Moreover, we derive the CraméRao bound (CRB) as a performance reference for the proposed algorithm. Compared with the existing algorithms, the proposed one improves the positioning performance of the vehicle with fewer carrier numbers and has more stable performance. Simulation results show that the performance curves of the proposed algorithm for parameters estimation are close to the corresponding CRBs, and the proposed algorithm can cope with more challenging cases when the line-of-sight (LOS) path does not exist.

In this paper, we propose a nested tensor-based framework for integrated near-field sensing and far-field communication assisted by reconfigurable intelligent surface (RIS). With the multi-dimensional resources of the considered integrated sensing and communication (ISAC) scenario and the Khatri-Rao space-time (KRST) coding, we formulate the received ISAC signal as a fourth-order nested tensor. By utilizing the algebraic structure of the nested tensor, a nested tensor-based joint sensing and communication scheme is designed to realize symbol detection and target localization without sending the specialized pilots. Moreover, the detection and localization accuracy is further improved by combining the dimensions of sensing and communication signals. Simulation results show that the proposed scheme provides superior ISAC performance with low complexity, which confirms the potential advantage of nested tensor-based framework in RIS-assisted ISAC systems.

In this letter, we propose an efficient off-grid sparse Bayesian learning (SBL) algorithm to estimate the near-field (NF) channel in ultra-scale massive multiple-input multiple-output (MIMO) systems. We first exploit the sparsity of the NF channel in the polar domain and perform an off-grid sampling of angles and distances. Then, an effective SBL method is proposed for sparse channel recovery and off-grid refinement. The sampled grid points are set to adjustable parameters, which undergo iterative updates by resorting to an accurate block majorization-minimization (MM) algorithm and gradient calculation. The proposed method demonstrates efficient channel estimation capabilities even in the absence of prior knowledge of the noise variance, leveraging the sparse characteristics of the NF channel. Simulation results demonstrate that our approach significantly improves the sparsity and accuracy of the NF channel representation. Furthermore, it outperforms the existing state-of-the-art algorithms in terms of estimation performance while requiring less pilot overhead.

We report the one-pot synthesis of N-CF3heteroaryl amides (NTFMHA) from heteroaryl carboxylic acids and sterically hindered isothiocyanates, including various amino acid analogues, in the presence of AgF. The key to this reaction is the utilization of free heteroaryl acyl chlorides, rather than their corresponding hydrochloride salts. This method represents a complementary method of our previous work and enables modification to a variety of previously inaccessible structures, including α-tertiary amines and N-CF3-modified pharmaceuticals.

To overcome the strength-toughness inversion relationship in steel/Fe matrix composites, a novel W-WC/Fe composite fiber-reinforced Fe matrix composite ((W-WC/Fe)f-IMC) with exceptional strength and toughness was fabricated by an in-situ fabrication method combining infiltration and in-situ solid-phase diffusion. The (W-WC/Fe)f-IMC consists of aligned W-WC/Fe composite fibers embedded in an Fe matrix. The W-WC/Fe composite fiber exhibits a characteristic core-shell structure on its cross section, with a resilient metal W fiber serving as the core and a robust annular WC-Fe layer acting as the shell. Due to the inward-outward growth and the gradient microstructure of the WC-Fe layer, the interface bonding strength between the W fiber/WC-Fe layer and the WC-Fe layer/matrix remains excellent. As a result, the (W-WC/Fe)f-IMC achieves an exceptional fracture strain of 35.5 ± 1.3 %, while maintaining high yield strength of 701 ± 16 MPa and ultimate compression strength of 1100 ± 18 MPa, surpassing those of cast Fe, which had values of 26.9 ± 1.1 %, 365 ± 20 MPa, and 834 ± 15 MPa, respectively. The simultaneous enhancement of the strength and toughness in (W-WC/Fe)f-IMC can be primarily attributed to the synergistic coupling effect between the high strength W-WC/Fe composite fibers and the tough matrix. The strategy proposed in this study holds promise as a method to alleviate the trade-off between strength and ductility in steel/Fe matrix composites.

• Ferromagnetic TiO 2 was prepared by regulation of crystal structure and defects. • The saturation magnetisation (M S) was measured to be as high as 0.0014 emu/g. • Experiments and simulation are used to investigate the ferromagnetism mechanism. • The photoelectrochemical performance was improved by ferromagnetic field in the bulk. • The proposed approach can be used to other oxide systems. The use of the internal magnetic field of ferromagnets can effectively promote charge separation and transfer (CST) in photoelectrochemical energy conversion. However, photoelectrochemical materials with a ferromagnetic field are scarce, and the internal magnetic field is negligible in nonferromagnetic materials. To address this issue, we propose a rational method for preparing ferromagnetic TiO 2 powder using controllable oxygen vacancies in anatase TiO 2 with co-exposed {001} and {101} facets. Accordingly, an excellent saturation magnetisation of 0.0014 emu/g in TiO 2 is achieved owing to an asymmetric and uneven charge distribution. Compared with that of nonferromagnetic TiO 2 , the efficiency of photocatalytic hydrogen generation of ferromagnetic TiO 2 is improved by 0.64 times. The enhancement of photocatalytic hydrogen generation is due to the different forces exerted on the electrons and holes in the magnetic field, which significantly improve the photogenerated CST efficiency of ferromagnetic TiO 2. This result highlights the significant role of the synergistic regulation of the crystal structure and defects in regulating the ferromagnetic characteristics of materials. The findings of this study provide guidance for leveraging point defects to promote CST for high-efficiency solar-energy conversion systems. Ferromagnetic TiO 2 with co-exposed {001} and {101} facets was prepared via controllable oxygen vacancies. The different forces exerted on the electrons and holes in the magnetic field significantly improve the photogenerated CST efficiency of ferromagnetic TiO 2 [Display omitted] [ABSTRACT FROM AUTHOR]

Both high-level and high-resolution feature representations are of great importance in various visual understanding tasks. To acquire high-resolution feature maps with high-level semantic information, one common strategy is to adopt dilated convolutions in the backbone networks to extract high-resolution feature maps, such as the dilatedFCN-based methods for semantic segmentation. However, due to many convolution operations are conducted on the high-resolution feature maps, such methods have large computational complexity and memory consumption. To balance the performance and efficiency, there also exist encoder-decoder structures that gradually recover the spatial information by combining multi-level feature maps from a feature encoder, such as the FPN architecture for object detection and the U-Net for semantic segmentation. Although being more efficient, the performances of existing encoder-decoder methods for semantic segmentation are far from comparable with the dilatedFCN-based methods. In this paper, we propose one novel holistically-guided decoder which is introduced to obtain the high-resolution semantic-rich feature maps via the multi-scale features from the encoder. The decoding is achieved via novel holistic codeword generation and codeword assembly operations, which take advantages of both the high-level and low-level features from the encoder features. With the proposed holistically-guided decoder, we implement the EfficientFCN architecture for semantic segmentation and HGD-FPN for object detection and instance segmentation. The EfficientFCN achieves comparable or even better performance than state-of-the-art methods with only 1/3 of their computational costs for semantic segmentation on PASCAL Context, PASCAL VOC, ADE20K datasets. Meanwhile, the proposed HGD-FPN achieves $>2\%$>2% higher mean Average Precision (mAP) when integrated into several object detection frameworks with ResNet-50 encoding backbones.

ABSTRACT An improved numerical model for steel reinforcement corrosion in concrete was developed to investigate the influences of temperature and relative humidity on process control and corrosion rate of steel [...]

ABSTRACT In order to overcome the disadvantages of traditional deterministic methods, a probabilistic evaluation method to assess the corrosion risk of steel reinforcement in concrete was proposed based on the [...]

Usually, different assays and instrumentation are required for different types of targets, e.g., nucleic acids, proteins, small molecules, etc., because of significant differences in their structures and sizes. To increase efficiency and reduce costs, a desirable solution is to develop a versatile platform suitable for diverse objectives. Here, we established a versatile detection technique: first, target separation and enrichment were carried out using magnetic beads (MBs); then, different targets were converted to same barcoded DNA strands (BDs) released from gold nanoparticles; finally, sensitive detection of three different targets (miRNA-21, digoxigenin antibody, and aflatoxin B1) was achieved through exonuclease III (Exo III) cyclic cleavage-assisted signal amplification. To simplify the operation, we integrated this technique into a microfluidic chip with multiple chambers in which the requisite reagents were prestored. Just by moving the MBs through different chambers with a magnet, multiple steps can be completed. Due to the limited space in microfluidic chips, the full mixing of MBs and solution is a key point to improve reaction efficiency. The mixing can be achieved by acoustic vibration generated by a small, portable sonic toothbrush. Based on the microfluidic chip, the detection limits of the above three targets were 0.76 pM, 0.16 ng/mL, and 0.56 nM, respectively. Furthermore, miRNA-21 and Digoxigenin antibody (Dig-Ab) in serum and AFB1in corn powder were also used to demonstrate the performance of this chip. Our versatile platform is easy to operate and is expected to develop into an automatic “sample-to-answer” device.

The design and construction of synthetic protocells capable of stimuli response and homeostatic regulation is an important challenge for synthetic protobiology. Here, we develop a step toward the construction of model protocells capable of a hypotonic stress-induced volume response that facilitates an increase in membrane permeability and the triggering of endogenous enzyme reactions. We describe a facile self-transformation process for constructing single- or multichambered molecularly crowded protocells based on the osmotic reconfiguration of lipid-coated coacervate droplets into multicompartmentalized coacervate vesicles. Hypotonic swelling broadens membrane permeability and increases transmembrane transport such that protease-based hydrolysis and enzyme cascades can be triggered and enhanced within the protocells by osmotically induced expansion. Specifically, we demonstrate how the enhanced production of nitric oxide (NO) within the swollen coacervate vesicles can be used to induce in vitroblood vessel vasodilation in thoracic artery rings. Our approach provides opportunities for designing reconfigurable model protocells capable of homeostatic volume regulation, dynamic structural reorganization, and adaptive functionality in response to changes in environment osmolarity, and could find applications in biomedicine, cellular diagnostics, and bioengineering.

When a company's automated manufacturing stumbles or grinds to a halt, the CFO's first question is likely to be, 'What is this really going to cost?' Measuring the full cost [...]

Implanting artificial organelles in living cells is capable of correcting cellular dysfunctionalities for cell repair and biomedical applications. In this work, phase-separated bienzyme-loaded coacervate microdroplets are established as a model of artificial membraneless organelles in endothelial dysfunctional cells for the cascade enzymatic production of nitric oxide (NO) with a purpose of correcting cellular NO deficiency. We prepared the coacervate microdroplets vialiquid-liquid phase separation of oppositely charged polyelectrolytes, in which glucose oxidase/horseradish peroxidase-mediated cascade reaction was compartmented. After the coacervate microdroplets were implanted in NO-deficient dysfunctional cells, the compartments maintained a phase-separated liquid droplet structure, which facilitated a significant enhancement of NO production in the dysfunctional cells. The recovery of NO production was further exploited to inhibit clot formation in blood plasma located in the cell suspension. This demonstrated a proof-of-concept design of artificial organelles in dysfunctional cells for cell repair and anticoagulation-related medical applications Our results demonstrate an approach for the construction of coacervate droplets through phase separation for the generation of artificial membraneless organelles, which can be designed to provide an array of functionalities in living organisms that have the potential to be used in the field of cell engineering and medical therapy.

Brilliant X- and γ-ray sources with ultrashort duration are widely pursued in fundamental science, industry and medicine. Compact femtosecond X-ray sources based on relativistic electrons accelerated by the laser wakefield in gases have performed outstandingly. Their energy conversion efficiency from laser to hard X-ray photons (>10 keV) is, however, limited to 10−7–10−5. Here we report the high-yield generation of hard X-ray flashes from targets made of carbon nanotubes, instead of gases. Orders-of-magnitude more electrons, accelerated to relativistic energy, are strongly wiggled inside a micrometre-scale, near-critical density plasma formed by the nanotube target, emitting 1012high-energy photons per shot. The yield of hard X-rays exceeds 1010photons per joule, corresponding to an unprecedented efficiency of 10−3. Irradiated by upcoming 10-PW-class lasers, such targets can deliver 10-MeV photons with brightness outperforming existing sources by two orders of magnitude.

To explore the influence of manufactured sand content on the flexural performance of self-compacting lightweight aggregate concrete (SCLC) beams, five SCLC beams with different manufactured sand dosage have been designed and fabricated for four-point bending tests. The workability and mechanical properties of the concrete mixture of each test beam are tested. It is observed that with the increase in the manufactured sand content, the workability of SCLC meets the standard requirements, and the mechanical properties are improved. The load–deflection curve, crack distribution pattern, and average strain of section are obtained through the four-point bending tests. The results reveal that the bending process of each test beam can be divided into three stages: uncracked stage, working stage with cracks, and failure stage. The average strain of section conforms to the assumption of plane section, and the load–deflection curve of each test beam is basically similar. With the increase in the manufactured sand content, the SCLC beam specimens exhibit more secondary cracks and more uniform crack distribution. Under the same level of load before yield, the maximum crack width decreases. The ultimate bearing capacity becomes maximum when the content of manufactured sand is 80%, which is 6.62% higher than that of SCLC beam with entire river sand. The plasticity coefficient of the resistance moment of the section is fitted by the experimental value, and the calculated value of cracking moment is in good agreement with the experimental value. Using the calculation formula for the maximum crack width of lightweight aggregate concrete and the fitting formula for the inhomogeneity coefficient of steel strain, the maximum crack width of each test beam is determined, which is in good agreement with the experimental value. Based on the test results and the calculated flexural bearing capacity, the optimal dosage of manufactured sand of SCLC concrete is obtained to be 60–80%.

Infectious diseases are caused by various pathogenic microorganisms that break through the human immune barrier, then reproduce and mutate in human cells, thus causing invasive disease. Despite many recent scientific and technological advances in fields, such as genetics, chemistry, and protein engineering, and in the efficiency of drug research and development, the discovery and development of novel and potent anti-infectious disease agents have still lagged behind. It is often challenging to keep up with the emergence and mutation of new pathogenic microorganisms, which leads to the emergence of more resistant pathogenic microorganisms. The emergence of aggregation-induced emission (AIE) fluorogens with high luminescence yields and high reactive oxygen species (ROS) production rates provides scientists with a new strategy for the prevention and treatment of pathogenic microorganisms. Due to their advantages in terms of brightness, biocompatibility, photostability, and positive correlation, AIE fluorogens (AIEgens) have great potential in biological applications. This review presents a systemic overview of recent progress in AIEgen-based platforms for the photodynamic therapy (PDT) of infectious diseases, which has emerged as a promising noninvasive alternative to traditional antibiotics for combating the drug resistance of infectious diseases. This review is mainly divided into two parts according to the type of pathogenic microorganisms: a section on bacterial and fungal infections (e.g., eye, skin, oral cavity, and blood infections), and a section on viral infections. The future prospects and potential clinical applications of AIEgens are also discussed in detail. In addition to motivating further interest in this field, this review is intended to promote ideas for the further exploration of AIEgens and the development of more advanced AIEgens in a broader range of biomedical and clinical applications.

Deblurring can not only provide visually more pleasant pictures and make photography more convenient, but also can improve the performance of objection detection as well as tracking. However, removing dynamic scene blur from images is a non-trivial task as it is difficult to model the non-uniform blur mathematically. Several methods first use single or multiple images to estimate optical flow (which is treated as an approximation of blur kernels) and then adopt non-blind deblurring algorithms to reconstruct the sharp images. However, these methods cannot be trained in an end-to-end manner and are usually computationally expensive. In this paper, we explore optical flow to remove dynamic scene blur by using the multi-scale spatially variant recurrent neural network (RNN). We utilize FlowNets to estimate optical flow from two consecutive images in different scales. The estimated optical flow provides the RNN weights in different scales so that the weights can better help RNNs to remove blur in the feature spaces. Finally, we develop a convolutional neural network (CNN) to restore the sharp images from the deblurred features. Both quantitatively and qualitatively evaluations on the benchmark datasets demonstrate that the proposed method performs favorably against state-of-the-art algorithms in terms of accuracy, speed, and model size.

Mg-based alloys are regard to be suitable hydrolysis materials for hydrogen generation. The mechanico-chemical reaction (MCR) strategy was employed to effectively activate Mg-based binary alloys as well as elevate their environmental stability. MCR is proved to be an effective way to activate Mg-based binary alloys and enhance the ability to resist environmental toxicity. The hydrolysis H2generation process of MCR Mg25Ni, Mg30Ce and Mg30La samples after environmental exposure are elevated and the final H2capacities can increase to 186.1, 204.8 and 341.4 mL·g−1with the fastest H2generation rates of 26.0, 24.2 and 41.5 mL·g−1·min−1, respectively. The generation capacities of the above-mentioned samples are 297, 370 and 629 mL·g−1at 318 K within 10 min, respectively. Mg-based binary alloys can be effectively activated by MCR and Maintain high reactivity at the same time. The hydrogen generation activation energies of MCR Mg25Ni, Mg30Ce and Mg30La after environmental exposure are 26.6, 30.8 and 23.3 kJ·mol−1, respectively. The above-mentioned work may provide a feasible strategy to activate the as-cast Mg-based alloys and elevate the Resistance to environmental toxicity, which may pave the way for applying the portable hydrogen generators.

Visualizing intracellular microRNA (miRNA) is of great importance for revealing its roles in the development of disease. However, cell membrane barrier, complex intracellular environment and low abundance of target miRNA are three main challenges for efficient imaging of intracellular miRNA. Here, we report a size-controllable and self-assembled DNA nanosphere with ATP-fueled dissociation property for amplified miRNA imaging in live cells and mice. The DNA nanosphere was self-assembled from Y-shaped DNA (Y-DNA) monomers through predesigned base pair hybridization, and the size could be easily controlled by varying the concentration of Y-DNA. Once the nanosphere was internalized into cells, the intracellular specific target miRNA would trigger the cyclic dissociation of the DNA nanosphere driven by ATP, resulting in amplified FRET signal. The programmable DNA nanosphere has been proven to work well for detecting the expression of miRNA in cancer cells and in mice, which demonstrates its fairish cell penetration, stability and sensitivity.

Blocking the interaction of MTDH/SND1 complex is an attractive strategy for cancer therapeutics. In this work, we designed and obtained a novel class of potent stabilized peptide inhibitors derived from MTDH sequence to disrupt MTDH/SND1 interaction. Through structure-based optimization and biological evaluation, stabilized peptides were obtained with tight binding affinity, improved cell penetration, and antitumor effects in the triple-negative breast cancer (TNBC) cells without nonspecific toxicity. To date, our study was the first report to demonstrate that stabilized peptides truncated from MTDH could serve as promising candidates to disrupt the MTDH/SND1 interaction for potential breast cancer treatment.

Objective: To examine the prevalence and correlates of HIV/syphilis infections and sexually transmitted diseases (STDs) among men who have sex with men (MSM) in Chongqing, China. Method: Cross-sectional surveys were conducted to provide information, including sociodemographics, sexual and drug use behaviors, HIV knowledge, and HIV-related services in 2006 and 2007, respectively. Multiple methods, including venue-based recruitment, community outreach, Internet advertisements, and peer referral, were used to identify men in Chongqing willing to participate in this study. Results: Of the 1692 participants, 10.8% were HIV-infected (range by district: 7.0%-15.0%), 8.6% were syphilis-infected, and 15.3% self-reported STD-related symptoms. HIV infection was associated with older age, recruitment from bathhouses/saunas, less education, more male sex partners, sex with a woman in the past 6 months, syphilis infection, and STD-related symptoms. Syphilis infection was associated with older age, less education, inconsistent condom use with a man, STD-related symptoms, and HIV infection. STD-related symptoms were associated with older age, being of nonlocal residency, inconsistent condom use with a humans, having ever paid for sex with a humans, HIV infection, and being from District 1. Conclusions: HIV and syphilis infections have reached alarmingly high rates in Chongqing's MSM population. Better targeted, in-depth and comprehensive intervention strategies are needed urgently, including education, condom promotion and distribution, STD control, drug use-related intervention, and advocacy for HIV counseling and testing with bridges to HIV prevention and care services. Widespread testing for HIV, syphilis, and other major STDs in this risk group should be considered as measures for control.

Most of the sentiment analysis studies focus on the sentimental classification of pictures in the video, ignoring the spatio-temporal information of the sequence of picture frames as well as text and audio information. The multiple kernel learning is a new hotspot in the field of nuclear machine learning, capable of handling multiple modalities. For multiple kernel learning, it is easy to ignore the basic features that are not discriminative, and cannot make full use of the base features of different modes. This paper puts forward a novel multi-modal fusion model for sentiment analysis, in which a multiple kernel learning algorithm based on convolution margin-dimension constraint is proposed for feature fusion. Moreover, the 3D convolutional neural network is used to extract the features of visual information, and the multiple kernel learning algorithm based on margin-dimension constraint is used to fuse visual, text and audio sentiment features. Experiments conducted on the MOUD and IEMOCAP sentiment databases show that the proposed model outperforms existing models in the field of multi-modal sentiment analysis research.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.compind.2006.12.004 Byline: Jianbo Liu (a), Dragan Djurdjanovic (a), Jun Ni (a), Nicolas Casoetto (a), Jay Lee (b) Keywords: Match matrix; Predictive maintenance; Time series prediction; Failure prediction Abstract: Full realization of all the potentials of predictive maintenance highly depends on the accuracy of long-term predictions of the remaining useful life of manufacturing equipments. In this paper, we propose a new method that is capable of achieving high long-term prediction accuracy by comparing signatures from any two degradation processes using measures of similarity that form a match matrix (MM). Through this concept, we can effectively include large amounts of historical information into the prediction of the current degradation process. Similarities with historical records are used to generate possible future distributions of features indicative of process performance, which are then used to predict the probabilities of failure over time by evaluating overlaps between predicted feature distributions and feature distributions related to unacceptable equipment behavior. The analysis of experimental results shows that the proposed method can yield a noticeable improvement of long-term prediction accuracy in terms of mean prediction errors over the Elman Recurrent Neural Network (ERNN) based prediction, which was shown in the past literature to predict well behavior of highly non-linear and non-stationary time series. Author Affiliation: (a) University of Michigan, Department of Mechanical Engineering, 2350 Hayward Street, Ann Arbor, MI 48109-2125, United States (b) University of Cincinnati, Department of Mechanical, Industrial and Nuclear Engineering, 598 Rhodes Hall, P.O. Box 210072, Cincinnati, OH 45221-0072, United States Article History: Received 18 February 2006; Revised 3 October 2006; Accepted 23 December 2006

Direct synthesis of liquid fuels (C5+hydrocarbons) through CO2hydrogenation has attracted considerable interest. However, it is plagued by high selectivity of C1 by-products (CO and CH4) and low reaction activity. Herein, we report that Na-decorated Fe catalysts promoted by combination of Mg and Mn and investigate their synergistic effect in the catalytic CO2hydrogenation reaction. The optimized amounts of promoters result in a significant improvement in the catalytic performance of NaFe2O3. The CO2conversion increases by 1.6-fold, while the total selectivity of CO and CH4is suppressed to below 21.3 %. The characteristic results reveal the enhanced surface alkalinity and electron transfer favor CO2adsorption and tuned the local H/C ratio in the vicinity of iron species, thus remarkably promoting the carbon chain growth and limiting the production of C1 products. This study offers a promising approach to modulating the metal electronic environment and improving carbon efficiency for CO2hydrogenation reactions.

Stable Hf0.5Zr0.5O2(HZO) sols were obtained by adding acetylacetone (AcAc), and the mechanism through which AcAc improved the quality of the sol and the gel film was analyzed. Absorption spectroscopy results show that AcAc can chelate with Hf4+and Zr4+, thus improving the hydrolysis resistance of the sol and the gel film, which optimizes their quality. Then, Pt/HZO/Pt structures were prepared via the sol–gel (SG) and pulsed laser deposition (PLD) methods, and their I–Vcurves were studied. The Pt/HZO/Pt structure prepared via the SG (PLD) method shows a pronounced bipolar resistance switching (BRS) (unipolar resistance switching (URS)) effect. It was found that there are several defects on the surface of the HZO film prepared via the SG method, which permit oxygen ions to enter/exit HZO, thus resulting in the BRS effect. However, there are fewer defects on the surface of the HZO film prepared via the PLD method, which results in the URS effect.

Land use patterns (LUPs) are the form in which various land use types are combined spatially, evidently impacting soil water. However, the influence mechanism by which LUPs form remains unclear. In this study, the soil water content (SWC) in the 0–160-cm soil depth was observed in shrubland (SL), mature forestland (MF), grassland (GL) and young forestland (YF) sites on four slopes with different LUPs in the Yangjuangou catchment of the Chinese Loess Plateau. The SWC in SL-YF-SL (13.28%) was significantly greater than that in YF-MF (9.93%), MF-GL-YF (10.38%) and SL-MF (10.83%) and was temporally stable during the study period. The spatial distribution of SWC along the slope differed among the four LUPs. Vegetation characteristics and soil texture mainly determined the spatial variations in SWC in the shallow soil layers (0–40 cm), while topographic factors were the determinants in the deep soil layers (60–160 cm) as well as in the entire soil profile (0–160 cm). The significance of SWC differences among the various land use patterns increased with decreasing precipitation during the growing seasons. YF-MF (77.8 mm) and SL-YF-GL (73.9 mm) required more rainwater than SL-MF (68.2 mm) and MF-GL-MF (67.5 mm) to compensate for the loss of soil water on the monthly scale during the rainy season. Therefore, vegetation restoration should consider land use patterns on hillslopes for soil water conservation.

Coronavirus disease 2019 (COVID-19) pandemic, a global health threat, was caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The SARS-CoV-2 papain-like cysteine protease (PLpro) was recognized as a promising drug target because of multiple functions in virus maturation and antiviral immune responses. Inhibitor GRL0617 occupied the interferon-stimulated gene 15 (ISG15) C-terminus-binding pocket and showed an effective antiviral inhibition. Here, we described a novel peptide–drug conjugate (PDC), in which GRL0617 was linked to a sulfonium-tethered peptide derived from PLpro-specific substrate LRGG. The EM-C and EC-M PDCs showed a promising in vitroIC50 of 7.40 ± 0.37 and 8.63 ± 0.55 μM, respectively. EC-M could covalently label PLpro active site C111 and display anti-ISGylation activities in cellular assays. The results represent the first attempt to design PDCs composed of stabilized peptide inhibitors and GRL0617 to inhibit PLpro. These novel PDCs provide promising opportunities for antiviral drug design.

8-Bromoguanosine is generated in vivo as a biomarker for early inflammation. Its formation and secondary reactions lead to a variety of biological sequelae at inflammation sites, most of which are mutagenic and linked to cancer. Herein, we report the formation of radical cations of 8-bromoguanine (8BrG•+) and 8-bromoguanosine (8BrGuo•+) and their reactions toward the lowest excited singlet molecular oxygen (1O2)─a common reactive oxygen species generated in biological systems. This work aims to investigate synergistic, oxidatively generated damage of 8-brominated guanine and guanosine that may occur upon ionizing radiation, one-electron oxidation, and 1O2oxidation. Capitalizing on measurements of reaction product ions and cross sections of 8BrG•+and 8BrGuo•+with 1O2using guided-ion beam tandem mass spectrometry and augmented by computational modeling of the prototype reaction system, 8BrG•++ 1O2, using the approximately spin-projected ωB97XD/6-31+G(d,p) density functional theory, the coupled cluster DLPNO-CCSD(T)/aug-cc-pVTZ and the multireference CASPT2(21,15)/6-31G**, probable reaction products, and potential energy surfaces (PESs) were mapped out. 8BrG•+and 8BrGuo•+present similar exothermic oxidation products, and their reaction efficiencies with 1O2increase with decreasing collision energy. Both single- and multireference theories predicted that the two most energetically favorable reaction pathways correspond to 1O2-addition to the C8 and C5-positions of 8BrG•+, respectively. The CASPT2-calculated PES represents the best quantitative agreement with the experimental benchmark, in that the oxidation exothermicity is close to the water hydration energy of product ions and, thus, is able to eliminate a water ligand in the product ions.

Artificial organelles are microcompartments capable of performing catalytic reactions in living cells to replace absent or lost cellular functions. Coacervate microdroplets, formed vialiquid–liquid phase separation, have been developed as membraneless organelles that mimic the dynamical organization of liquid organelles. However, the further studies focusing on cellular implanting of coacervate microdroplets in living cells to supplement the dysfunction of natural cells are still rare. Here catalase (CAT)-containing coacervate microdroplets, developed as artificial membraneless organelles with unique liquid compartments, were integrated into living cells to scavenge intracellular massive reactive oxygen species (ROS) and recover cell viability. The enzyme-containing coacervate microdroplets were constructed by sequestering CAT in poly(dimethyldiallylammonium chloride) (PDDA)/polyacrylic acid (PAA) coacervate microdroplets; their liquid-like fluidity was revealed by fluorescence recovery after bleaching, and coalescence experiment in vitroand in living cells. After cellular internalization, the coacervate microdroplets remained in the polymer-rich dense phase and retained enzymatic activities. CAT-mediated H2O2removal and ROS scavenging in living cells decreased the cytotoxicity of H2O2, improving cell viability. The cell internalization of coacervate microdroplets in vitroprovides a novel approach for designing artificial membraneless organelles in living cells. The strategy of using artificial organelle-mediated enzymatic reactions to supplement cellular dysfunctions can be exploited for their further biomedical applications.

The word similarity task is used to calculate the similarity of any pair of words, and is a basic technology of natural language processing (NLP). The existing method is based on word embedding, which fails to capture polysemy and is greatly influenced by the quality of the corpus. In this paper, we propose a multi-prototype Chinese word representation model (MP-CWR) for word similarity based on synonym knowledge base, including knowledge representation module and word similarity module. For the first module, we propose a dual attention to combine semantic information for jointly learning word knowledge representation. The MP-CWR model utilizes the synonyms as prior knowledge to supplement the relationship between words, which is helpful to solve the challenge of semantic expression due to insufficient data. As for the word similarity module, we propose a multi-prototype representation for each word. Then we calculate and fuse the conceptual similarity of two words to obtain the final result. Finally, we verify the effectiveness of our model on three public data sets with other baseline models. In addition, the experiments also prove the stability and scalability of our MP-CWR model under different corpora.

This article introduces a novel hybrid structure named as interval-valued neutrosophic N-soft sets (IVNNSSsin short) by a reasonable and innovative combination, connecting interval-valued neutrosophic soft sets to N-soft sets. The new model is illustrated with useful properties and real example. Moreover, we give the extend relations on interval-valued neutrosophic N-soft sets with some operations. Finally, group decision making application of IVNNSSsis given by the extend relation contrast ranking method as a new algorithm. The core of the new algorithm is the extended relationship, which can solve the decision problem when encountering two or more classes of attribute sets. And extend relation contrast ranking method is more suitable for the information of IVNNSSs. Then compared with the TOPSIS, the proposed algorithm is more concise and easy to operate.

Chiral growth and chirality transfer associated with plasmonic nanostructures have rejuvenated the field of chirality. As the precise regioselective growth of inorganic crystals into chiral shapes at the nanoscale is extremely challenging, “bottom-up” synthesis of intrinsically chiral nanoparticles with structural stability is obviously attractive and important. With the thiolated bimolecular cosurfactants, we demonstrated a chemical strategy for the synthesis of intrinsically helical plasmonic nanorods (HPNRs) with strong and tailorable plasmonic circular dichroism (PCD) responses, deriving from the zwitterionic interactions between the −NH3+and −COO–groups of the cysteine molecules (Cys). The influence of structural parameters of HPNRs on PCD responses was analyzed systematically by theoretical simulations. Among the different structural parameters, the pitch depth was found to have the greatest impact on the PCD signals, in agreement with the experimental results. Moreover, the obtained HPNRs with the strong, tunable, and stable chiroptical properties were found to be able to induce circularly polarized luminescence of achiral luminophores. Due to the generality of this effect, this chiral plasmonic nanostructure may have great potential for use in the fields of chiral sensors, chiral catalysis, and displays.

A number of applications require x rays of both high flux and narrow bandwidth. In this work, we experimentally demonstrate the high-efficiency generation of narrowband soft x rays from carbon nanotube foams irradiated by a femtosecond laser pulse at an intensity of 10^19W/cm^2. The building blocks of the foam, single-walled carbon nanotube bundles with diameters smaller than the laser skin length can be volumetrically heated and fully ionized on a femtosecond time scale. The three-dimensional network structure of the foam permits deep penetration and drastic absorption of the laser pulse, and results in bright line emissions without prominent Stark broadening. A single-shot yield of 3×10^14photons in the carbon Ly_α line at 3.37 nm was measured with a bandwidth of 0.013 nm.

Increasing the local concentration of DNA-based probes is a convenient way to improve the sensitivity of biosensors. Instead of using organic solvents or ionic liquids that phase-separate with water based on hydrophobic interactions, we herein studied a classic aqueous two-phase system (ATPS) comprising polyethylene glycol (PEG) and dextran. Polymers of higher molecular weights and higher concentrations favored phase separation. DNA oligonucleotides are selectively enriched in the dextran-rich phase unless the pH was increased to 12. A higher volume ratio of PEG-to-dextran and a higher concentration of PEG also enrich more DNA probes in the dextran-rich phase. The partition efficiency of the T15DNA was enriched around seven times in the dextran phase when the volume ratio of dextran and PEG reached 1:10. The detection of limit improved by 3.6-fold in a molecular beacon-based DNA detection system with the ATPS. The ATPS also increased the sensitivity for the detection of Hg2+and adenosine triphosphate, although these target molecules alone distributed equally in the two phases. This work demonstrates a simple method using water soluble polymers to improve biosensors.

For intracellular molecular detection, the appropriate probes should include the abilities to enter target cells noninvasively, target specific sites, and then respond to the analytes reliably. Herein, a ratiometric fluorescent DNA nanostructure (RFDN) was designed for mitochondrial adenosine triphosphate (ATP) imaging in living cells. The DNA nanostructure was constructed by continuous hybridization of two hairpin DNA strands (HS1-Cy3 and HS2-Cy5) under the initiation of the trigger. HS1-Cy3 and HS2-Cy5 contained split aptamer fragments of ATP and are labeled with a fluorescent donor (Cy3) and acceptor (Cy5), respectively. The RFDN integrated multiple split aptamer fragments and increased the local concentration of sensing probes. The binding of ATP to aptamer fragments on the RFDN shortened the distance between Cy3 and Cy5, resulting in obvious ratiometric signals (fluorescence resonance energy transfer). The RFDN showed good biocompatibility and can be internalized into cells in a caveolin-dependent endocytosis pathway. The co-localization imaging results indicated that the DNA nanostructure could target the mitochondria viaCy3 and Cy5. Moreover, the confocal imaging results showed that the intracellular ATP changes stimulated by drugs in living cells could be indicated by the RFDN. In this way, the RFDN is expected to be a simple, flexible, and general platform for chemo/biosensing in living cells.

Reactions of electronically excited singlet oxygen (1O2) with the radical cations of guanine (9HG•+), 9-methylguanine (9MG•+), 2′-deoxyguanosine (dGuo•+), and guanosine (Guo•+) were studied in the gas phase by a combination of guided-ion-beam mass spectrometric measurement of product ions and cross sections as a function of collision energy (Ecol) and electronic structure calculations of the reaction potential energy surface (PES) at various levels of theory. No product could be captured in the 1O2reaction with bare 9HG•+or 9MG•+, because energized products decayed rapidly to reactants before being detected. To overcome this unfavorable kinetics, monohydrated 9HG•+·H2O and 9MG•+·H2O were used as reactant ions, of which the peroxide product ions were stabilized by energy relaxation viaelimination of the water ligand. Reaction cross sections for 9HG•+·H2O and 9MG•+·H2O decrease with increasing Ecol, becoming negligible above 0.6 eV. This indicates that the reactions are exothermic with no barriers above reactants and the heat of formation of the products is sufficiently large to overcome their water ligand elimination energy (0.7 eV). Peroxide product ions were also detected in the 1O2reactions with unhydrated dGuo•+and Guo•+, in which intramolecular vibrational redistribution was able to stabilize oxidation products. 9MG•+was utilized as a model system to explore the reaction PES for the initial 1O2addition to the guanine radical cation. Calculations were carried out using single-reference ωB97XD, RI-MP2, and DLPNO-CCSD(T) and multireference CASSCF and CASPT2. Although the same PES profile was obtained at different levels of theory, the energies of the mixed open- and closed-shell 1O2reactant and the open-shell reaction intermediates, transition states, and products are sensitive to the theories. By taking into account both static and dynamic electron correlations, the CASPT2 PES has provided the best agreement with the experimentally measured reaction thermodynamics and predicted 8-peroxide as the most probable initial oxidation product of the guanine radical cation.

Although giant unilamellar vesicles (GUVs) have been extensively studied as synthetic cell-like microcompartments, their applicability as cytomimetic models is severely compromised by low levels of membrane permeability, low encapsulation efficiencies, and high physicochemical instability. Here, we develop an integrated cytomimetic model comprising a macromolecularly crowded interior with high sequestration efficiency and enclosed within a phospholipid membrane that is permeable to molecules below a molecular weight cutoff of ca. 4 kDa. The protocells are readily prepared by spontaneous assembly of a phospholipid membrane on the surface of preformed polynucleotide/polysaccharide coacervate microdroplets and are designated as giant coacervate vesicles (GCVs). Partial anchoring of the GCV membrane to the underlying coacervate phase results in increased robustness, lower membrane fluidity, and increased permeability compared with GUV counterparts. As a consequence, enzyme and ribozyme catalysis can be triggered in the molecularly crowded interior of the GCV but not inside the GUVs when small molecule substrates or inducers are present in the external environment. By integrating processes of membrane-mediated compartmentalization and liquid–liquid microphase separation, GCVs could offer substantial advantages as cytomimetic models, synthetic protocells, and artificial biomolecular microreactors.

Direct dynamics simulations of HNO3with dicyanamide anion DCA–(i.e., N(CN)2–) and dicyanoborohydride anion DCBH–(i.e., BH2(CN)2–) were performed at the B3LYP/6-31+G(d) level of theory in an attempt to elucidate the primary and secondary reactions in the two reaction systems. Guided by trajectory results, reaction coordinates and potential energy diagrams were mapped out for the oxidation of DCA–and DCBH–by one and two HNO3molecules, respectively, in the gas-phase and in the condensed-phase ionic liquids using the B3LYP/6-311++G(d,p) method. The oxidation of DCA–by HNO3is initiated by proton transfer. The most important pathway leads to the formation of O2N–NHC(O)NCN–, and the latter reacts with a second HNO3to produce O2N–NHC(O)NC(O)NH–NO2–(DNB–). The oxidation of DCBH–by HNO3may follow a similar mechanism as that of DCA–, producing two analogue products: O2N–NHC(O)BH2CN–and O2N–NHC(O)BH2C(O)NH–NO2–. Moreover, two new, unique reaction pathways were discovered for DCBH–because of its boron-hydride group: (1) isomerization of DCBH–to CNBH2CN–and CNBH2NC–and (2) H2elimination in which the proton in HNO3combines with a hydride-H in DCBH–. The Rice–Ramsperger–Kassel–Marcus (RRKM) theory was utilized to calculate reaction kinetics and product branching ratios. The RRKM results indicate that the formation of DNB–is exclusively important in the oxidation of DCA–, whereas the same type of reaction is a minor channel in the oxidation of DCBH–. In the latter case, H2elimination becomes dominating. The RRKM modeling also indicates that the oxidation rate constant of DCBH–is higher than that of DCA–by an order of magnitude. This rationalizes the enhanced preignition performance of DCBH–over DCA–with HNO3.

The design and construction of synthetic therapeutic protocells capable of establishing cognate chemical communication channels with living cells is an important challenge for synthetic biology and bio-engineering. Here we develop a step towards protocell-mediated nitric-oxide-induced vasodilation by constructing a new synthetic cell model based on bio-derived coacervate vesicles with high haemocompatibility and increased blood circulation times. The hybrid protocells are prepared by the spontaneous self-assembly of haemoglobin-containing erythrocyte membrane fragments on the surface of preformed polysaccharide–polynucleotide coacervate micro-droplets containing glucose oxidase. We use the sequestered enzymes to program a spatially coupled glucose oxidase/haemoglobin reaction cascade, which in the presence of glucose and hydroxyurea generates a protocell-mediated flux of nitric oxide that we exploit for in vitro and in vivo blood vessel vasodilation. Taken together, our results provide new opportunities for the development of endogenously organized cell-like entities (biocompatible micro-bots) geared specifically towards active interfacing with individual living cells and cell communities.