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We describe a new no-reference blur index for still images based on a singular value curve (SVC). The algorithm is composed of two steps. First, the singular value decomposition is performed on the image to be blur-assessed. Then an image blur index is constructed from the singular value curve. Experimental results obtained on four simulated blur databases and on the Real Blur Image Database show that the proposed SVC algorithm achieves high correlation against human judgments when assessing the blur distortion of images. [ABSTRACT FROM AUTHOR]

Strong-field terahertz (THz) light-matter interaction provides various nonlinear control approaches in condensed matter physics, energy and material sciences, electron acceleration, and manipulation. Recently developed spintronic THz emission with minimum complexities has been demonstrated to have the capability for generating high field strengths. Up to now, nonlinear applications based on the spintronic THz transients have yet been realized. Here, we report THz emission from two-color femtosecond laser plasma filaments modulated by a 60-kV/cm THz pulse from W/CoFeB/Pt heterostructures. Enhanced THz radiation based on electron acceleration in plasma is recorded when the direction of the spintronic THz modulating field is in line with that of the electron movement. This behavior is quantitatively reproduced by a local current model of the plasma THz source. Our experimental and theoretical results may inspire further nonlinear THz investigation and accelerate ultrafast THz engineering in matter. [ABSTRACT FROM AUTHOR]

In order to investigate energy supply capacity and oil production contribution of near-fracture and fracture-free zone in fractured tight oil reservoirs, a series of CO2 huff-and-puff tests were designed and carried out in different experimental conditions. A fracture-matrix long-core system was established to simulate the near-fracture zone and matrix zone of tight oil reservoirs. The NMR technique was utilized to identify the microscopic remaining oil of certain core samples. The effects of fracture length, soaking time, depressurization method, and asphaltene precipitation on the oil recovery performance of CO2 huff-and-puff process were evaluated, respectively. The results indicated that the dissolution and diffusion range of the injected CO2 can be apparently increased from both macro and micro aspects through increasing the length or density of the fractures and extending the soaking time; and, during puff period, the slow depressurization method has better recovery effect on near-fracture zone, while the step depressurization method has better recovery effect on distal fracture-free matrix. After CO2 huff-and-puff process, the oil recovery of the medium pores near fracture could be close to oil recovery of the large pores, which is higher than 60%. But, in the distal matrix, the oil recovery of the medium pores was only a little higher than depletion development. The remaining oil of medium pores in distal fracture-free matrix still has great potential to be developed after CO2 huff-and-puff process. [ABSTRACT FROM AUTHOR]

With the development of mobile phone camera technology, mobile phones can take a large number of macro photography images that previously could only be taken by professional cameras. Therefore, it is of great significance to study the quality of macro photography images. For this reason, a macro photography image visual quality evaluation database is established and it is named as MP2020. The database contains 100 reference images and 800 distorted images of four distortion types, including 200 distorted images of JPEG 2000, 200 distorted images of JPEG, 200 distorted images of white noise, and 200 distorted images of Gaussian blur. The DMOS values in the database were calculated from 48000 data which are provided by 60 subjects. Ten classical image quality assessment algorithms were tested on the MP2020 database. The experimental results show that the existing image quality assessment algorithms, which are widely used, are not applicable to the macro photography images. Therefore, MP2020 would contribute to the improvement of existing algorithms and the development of new algorithms. MP2020 has been uploaded to GitHub for download. [ABSTRACT FROM AUTHOR]

Plenty of works have done to enhance the piezoelectricity of potassium-sodium niobate (KNN), aiming to replace lead-zirconate titanate (PZT) in the consideration of eco-friendly requirement. However so far, KNN ceramics with high piezoelectric performances tend to have a low mechanical quality factor (Q m), which could result in excessive dielectric loss, especially when working in high frequencies. Thus, increasing Q m is a crucial task in KNN-based ceramics. By constructing phase boundaries together with inducing oxygen vacancies, a new KNN ceramic system is built by using conventional solid-state method with high Q m (>250), high piezoelectric performance as well as outstanding temperature stability. Optimum overall properties of KNN-based ceramics can be as large as d 33 = 231 pC/N, Q m = 355, T C = 366 °C. This work provides a deeper insight to KNN-based ceramics with high mechanical quality factor and makes a progress on the high frequency application of lead-free ceramics. [ABSTRACT FROM AUTHOR]

Fuel cavitation can cause damage to the structure of an injector control valve, which can further affect the service life of the injector. Therefore, it is of great importance to carry out research on the mechanism of cavitation in injector control valves. In this study, the dynamic evolution of the cavitation and fuel flow characteristics during the opening of a ball valve in a high‐pressure common rail injector control valve were studied. First, a transient CFD simulation of the cavitation during the opening of the control valve was performed using dynamic mesh technology to analyze the evolution and formation mechanism of the cavitation. The cavitation was influenced by the fuel flow velocity, which was affected by the sealing cone angle and the ball valve movement. Additionally, the fuel reflux could effectively inhibit the development of cavitation. By comparing with the pressure, velocity, and mass flow rate of the fuel under conditions without cavitation, it was found that the cavitation had a remarkable effect on reducing the hydraulic shock to the ball valve and sealing cone as well as stabilizing the fluctuation of the fuel velocity in the control chamber. In addition, the cavitation noticeably decreased the fuel mass flow rate (by up to 32% at 0.015 ms) and increased the average pressure in the chamber (by up to 29.1% at 0.01 ms), ultimately leading to a slower response of the control valve. The analysis of different inlet pressures of the control valve indicated that the increase in the inlet pressure caused the cavitation to extend upward along the sealing cone, and that the cavitation ring area and the cavitation strength increased. [ABSTRACT FROM AUTHOR]

Based on the present semi-empirical model of numerically predicting aerodynamic noise from wind turbine, effects of .several important parameters on aerodynamic noise from wind turbine are studied in the paper. To better simulate vortex-shedding noise near the tip of blade, tip loss correction is added in the present semi-model at the domain of blade tip. Using the noise predicting model developed in the paper, four different important parameters including blade airfoil, tip pitch angle, rotor angular speed and tail edge bluntness are mainly discussed in the paper, where the pattern of noise level with the frequency and A-weighted total sound power level and sound pressure level are also analyzed in detail. These influential patterns of the different aerodynamic parameters can provide technical references for the design and manufacture of low noise wind turbine, which helps to the study on the reduction of aerodynamic noise from wind turbine. [ABSTRACT FROM AUTHOR]

Understanding gas transport in shale matrix is of great significance for reservoir evaluation and gas well productivity. Up to now, numerous transport models were developed based on the hypothesis of homogeneous confined cylindrical nanopores by coupling with multiple mechanisms. In this work, a new transport model is proposed by coupling different transport mechanisms employing the volume fraction of organic matter (OM) instead of the total organic carbon content (TOC). The signature that the OM density is generally lower than the bulk matrix is also considered. The porosity of OM and inorganic matter (iOM) is determined by rock pyrolysis analysis, respectively. Water distribution in OM and iOM pores in the form of water clusters and adsorbed water films is quantified by water adsorption experiments. Gas transport model in moisturized shale matrix pores is then established considering the difference in water distribution. Meanwhile, both of the proposed models are analytical solutions with the hypothesis that the OM and iOM are arranged parallelly. The impacts of different factors on gas transport capacity are analyzed and discussed. Results indicate that the apparent permeability of the shale matrix decreases with the decline of pore radius. For the same pore diameter, the gas transport capacity of OM pores is much greater than that of iOM pores. The apparent permeability decreases with the increasing OM fraction. The irreducible water within the shale matrix can reduce the gas flow capacity considerably, and the apparent permeability is more sensitive to the change of irreducible water saturation at low pressure comparing with that at high pressure. This study sheds fundamental light on the gas transport distinctions in dry and moisturized shale matrix, which provides insights into the development of water-bearing shale gas reservoirs. • Gas transport models for dry and moisturized shale matrix were established by quantifying irreducible water. • The contribution of gas slip flow to the total gas transport in the shale matrix decreases because of the real gas effect. • The apparent permeability is more sensitive to the change of irreducible water saturation at lower pressure. [ABSTRACT FROM AUTHOR]

Enhanced comprehensive performances of piezoelectric and temperature stability are obtained in 0.725Bi 1.05 Fe x O 3 -0.275BaTiO 3 -0.3%MnO 2 ceramics via tuning nonstoichiometric Fe content. The Fe content strongly affects the phase structure of ceramics, which possess rhombohedral-pseudocubic coexistence structure, boosting the high piezoelectricity in this system. The optimal comprehensive performances of ceramics are obtained at x ​= ​0.98 with a relatively large piezoelectricity (d 33 ∼158 ​pC/N) as well as a high Curie temperature (T C ∼523 ​°C). We found that the deficiency of Fe content gives rise to diffused phase boundary and oxygen vacancies, which induces strong thermal stability over a wide temperature range in the composition. This work discloses the Fe content play an important role in the crystal structure of BF-based materials. We expect that the investigation on nonstoinchiometry of Fe will lead an effective method to develop high-performance BiFeO 3 -based ceramics for lead-free electronic applications. [Display omitted] • The influence of doped Fe content in BF-BT ceramics on crystal structure has been investigated through the Rietvled refinement, especially on the distortion degree of phase. • The effect of Fe content on microstructure, especially the temperature stability of domain structure, was studied. • The BF x -BT-Mn ceramics have huge potential for application because of its excellent piezoelectric properties and high Curie temperature. [ABSTRACT FROM AUTHOR]

This article, titled "Simultaneous Terahertz Pulse Generation and Manipulation with Spintronic Coding Surface," explores the integration of terahertz radiation generation and manipulation using spintronic technology. The researchers demonstrate the ability to control the spatial phase of radiated terahertz waves, allowing for the creation of focusing, beam-steering, and vortex beams. The study was conducted by a team of authors including Sai Chen, Hanchen Wang, Jingyu Liu, Mingxuan Zhang, Peng Chen, Peiyan Li, Zhongkai Liu, Xiufeng Han, Caihua Wan, Haiming Yu, Yan Zhang, and Xiaojun Wu. [Extracted from the article]

Dance action recognition is a hot research topic in computer vision. However, current skeleton-based action recognition methods face difficulties in capturing the adequate spatial structure and temporal variations of dance actions, resulting in lower recognition accuracy. In this paper, we propose a Hierarchical Fusion Adaptive Graph Transformer network (HFA-GTNet) for dance action recognition. A Hierarchical Spatial Attention (HSAtt) module is designed to extract different levels of spatial feature information from joint to parts to group, it can effectively learn high-order dependency relationships from local joints to global poses in dance actions. Secondly, to extract the joint variations in dance actions at different speeds, we have designed a Temporal Fusion Attention (TFAtt) module. This module learns the short-term and long-term temporal dependencies among joints across frames. Additionally, to capture the variations in motion patterns and dance styles among different dancers, we introduce an Adaptive Component (AdaptC). Finally, we evaluate our model on two self-built dance datasets, MSDanceAction and InDanceAction, and demonstrate its superior performance compared to other state-of-the-art methods in dance action recognition. • A novel attention mechanism is designed to model spatial correlations. • A three-branch module is proposed to capture temporal relations among all frames. • An component is introduced to handle the spatial and temporal variations. • Two different types dance action datasets are constructed. [ABSTRACT FROM AUTHOR]

Background: Patients with initially unresectable colorectal liver metastases (CRLM) could achieve survival benefit from successful conversion therapy. Recently, Tumor Burden Score (TBS) was proposed as a valuable index to predict outcome following resection of CRLM. The study is aimed to investigate the association of TBS with conversion outcome. Methods: A total of 234 patients who underwent first-line treatment in our center were enrolled as training cohort. The validation cohort was developed from 89 patients in our previous study. Cut-off value of TBS was calculated to stratify patients into two groups. Significance test and logistic regression model were used to examine the prediction value of TBS for conversion outcome after first-line systemic therapy. Kaplan–Meier method and Cox proportional hazard model were applied to assess the prognostic value of TBS. Results: TBS showed good discriminatory power [area under curve (AUC) 0.726, p < 0.001] with cut-off value defined as 14.3 in training cohort, which was validated in the validation cohort. Increasing TBS was related to adverse chemotherapy response and conversion outcome. Low TBS group had three times higher conversion rate than that in high TBS group (57.3% versus 19.0%, p < 0.001). Multivariate analysis indicated that high TBS [odds ratio (OR) = 3.676, 95% confidence interval (CI) 1.671–8.429, p = 0.002], first-line treatment response as stable disease (SD) or progressive disease (PD) (OR = 9.247; 95% CI 4.736–18.846, p < 0.001), and absence of targeted therapy (OR = 2.453, 95% CI 1.139–5.455, p = 0.024) were three independent risk factors for failure conversion outcome. High TBS was significantly associated with conversion outcome whatever chemotherapy response, addition of targeted therapy, and Kirsten rat sarcoma viral oncogene homolog (KRAS) status. High TBS was also associated with worse overall survival. Conclusion: TBS should be applied in clinical practice to predict conversion outcome in patients with initially unresectable CRLM. [ABSTRACT FROM AUTHOR]

Satellite-derived land surface temperatures (LSTs) are a critical parameter in various fields. Unfortunately, there are numerous gaps in LST products due to cloud contamination and orbital gaps. In previous studies, various gapfilling methods have been developed. However, most of those methods use only spatiotemporal information to fill gaps. In this study, a gapfilling method called the enhanced hybrid (EH) method that integrates spatiotemporal information and information from other similar LST products was proposed. The accuracy of the EH method was compared with the accuracies of three other gapfilling methods that only use spatiotemporal information: Remotely Sensed DAily land Surface Temperature reconstruction (RSDAST), interpolation of the mean anomalies (IMAs), and Gapfill. It was found that the correlations between the four LST products were strong, indicating that using information from other products may improve the accuracy of gapfilling. On average, the mean absolute errors (MAEs) of the data filled using the EH method were 23.7%–52.7% lower than those of RSDAST, 35.4%–38.7% lower than those of IMA, and 38.5%–46.9% lower than those of the Gapfill method. The usage of information from other similar LST products was the main reason for the high accuracy observed for the EH method. In addition, the LST images filled using the RSDAST and IMA methods had some outliers, while there were fewer obvious outliers in the LST images filled with the EH method. It was concluded that the EH method is a robust gapfilling method with a high accuracy. [ABSTRACT FROM AUTHOR]

The current severe situation of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has not been reversed and posed great threats to global health. Therefore, there is an urgent need to find out effective antiviral drugs. The 3-chymotrypsin-like protease (3CLpro) in SARS-CoV-2 serve as a promising anti-virus target due to its essential role in the regulation of virus reproduction. Here, we report an improved integrated approach to identify effective 3CLpro inhibitors from effective Chinese herbal formulas. With this approach, we identified the 5 natural products (NPs) including narcissoside, kaempferol-3-O-gentiobioside, rutin, vicenin-2 and isoschaftoside as potential anti-SARS-CoV-2 candidates. Subsequent molecular dynamics simulation additionally revealed that these molecules can be tightly bound to 3CLpro and confirmed effectiveness against COVID-19. Moreover, kaempferol-3-o-gentiobioside, vicenin-2 and isoschaftoside were first reported to have SARS-CoV-2 3CLpro inhibitory activity. In summary, this optimized integrated strategy for drug screening can be utilized in the discovery of antiviral drugs to achieve rapid acquisition of drugs with specific effects on antiviral targets. [ABSTRACT FROM AUTHOR]

Abstract: Background context: Laminectomy is the traditional approach to intramedullary ependymomas and may lead to spinal instability and spinal deformities. Hemilaminectomy and laminoplasty have been developed to preserve the spinal stability and have been found to be effective. Unilateral, multilevel, interlaminar fenestration is another approach that may have more advantages in preserving the spinal stability; however, it has rarely been used by now. Purpose: Unilateral, multilevel, interlaminar fenestration was often used in the surgical treatment of degenerative lumbar stenosis; however, it was rarely used for tumors. The aim of this study was to discuss the characteristics and advantages of its use for a multisegment intramedullary ependymoma. Study design: Case report and literature review. Methods: The 22-year-old man suffered from muscular atrophy of the left hand and the right hand for a period of 1.5 years and 3 months, respectively, and the cervical magnetic resonance imaging revealed an intramedullary mass of C4–C7. A right, unilateral, multilevel, interlaminar fenestration of the C3–C7 was performed with the help of high-speed air drills, and a midline myelotomy was made under microscope. The tumor was removed totally using piecemeal resection. Results: The magnetic resonance imaging, obtained 1 year after the operation, revealed that there were no residual mass lesion and no spinal instability, and the patient acquired an excellent functional outcome. So, this technique proved to be safe and easy in this case. Conclusions: Unilateral, multilevel, interlaminar fenestration allows good access to a long intraspinal segment, protects the structures essential to spinal stability as much as possible, preserves the spinal stability, and results in no additional injury to the spinal cord. It may be applicable to many other kinds of intraspinal tumors. [Copyright &y& Elsevier]

Southern rust ( Puccinia polysora Underw.) is a major disease that can cause severe yield losses in maize ( Zea mays L.). In our previous study, a major gene RppP25 that confers resistance to southern rust was identified in inbred line P25. Here, we report the fine mapping and candidate gene analysis of RppP25 from the near-isogenic line F939, which harbors RppP25 in the genetic background of the susceptible inbred line F349. The inheritance of resistance to southern rust was investigated in the BC1F1 and BC3F1 populations, which were derived from a cross between F939 and F349 (as the recurrent parent). The 1:1 segregation ratio of resistance to susceptible plants in these two populations indicated that the resistance is controlled by a single dominant gene. Ten markers, including three simple sequence repeat (SSR) markers and seven insertion/deletion (InDel) markers, were developed in the RppP25 region. RppP25 was delimited to an interval between P091 and M271, with an estimated length of 40 kb based on the physical map of B73. In this region, a candidate gene was identified that was predicted to encode a putative nucleotide-binding site leucine-rich repeat (NBS-LRR) protein. Two co-segregated markers will aid in pyramiding diverse southern rust resistance alleles into elite materials, and thereby improve southern rust resistance worldwide. [ABSTRACT FROM AUTHOR]

Abstract: Solving the multi-stage portfolio optimization (MSPO) problem is very challenging due to nonlinearity of the problem and its high consumption of computational time. Many heuristic methods have been employed to tackle the problem. In this paper, we propose a novel variant of particle swarm optimization (PSO), called drift particle swarm optimization (DPSO), and apply it to the MSPO problem solving. The classical return-variance function is employed as the objective function, and experiments on the problems with different numbers of stages are conducted by using sample data from various stocks in S&P 100 index. We compare performance and effectiveness of DPSO, particle swarm optimization (PSO), genetic algorithm (GA) and two classical optimization solvers (LOQO and CPLEX), in terms of efficient frontiers, fitness values, convergence rates and computational time consumption. The experiment results show that DPSO is more efficient and effective in MSPO problem solving than other tested optimization tools. [Copyright &y& Elsevier]

We develop a no-reference image quality assessment (QA) algorithm that deploys a general regression neural network (GRNN). The new algorithm is trained on and successfully assesses image quality, relative to human subjectivity, across a range of distortion types. The features deployed for QA include the mean value of phase congruency image, the entropy of phase congruency image, the entropy of the distorted image, and the gradient of the distorted image. Image quality estimation is accomplished by approximating the functional relationship between these features and subjective mean opinion scores using a GRNN. Our experimental results show that the new method accords closely with human subjective judgment. [ABSTRACT FROM AUTHOR]

Abstract: QoS multicast routing in networks is a very important research issue in networks and distributed systems. It is also a challenging and hard problem for high-performance networks of the next generation. Due to its NP-completeness, many heuristic methods have been employed to solve the problem. This paper proposes the modified quantum-behaved particle swarm optimization (QPSO) method for QoS multicast routing. In the proposed method, QoS multicast routing is converted into an integer programming problem with QoS constraints and is solved by the QPSO algorithm combined with loop deletion operation. The QPSO-based routing method, along with the routing algorithms based on particle swarm optimization (PSO) and genetic algorithm (GA), is tested on randomly generated network topologies for the purpose of performance evaluation. The simulation results show the efficiency of the proposed method on QoS the routing problem and its superiority to the methods based on PSO and GA. [ABSTRACT FROM AUTHOR]

Abstract: Inspired by the motion of electrons in metal conductors in an electric field, we propose a variant of Particle Swarm Optimization (PSO), called Drift Particle Swarm Optimization (DPSO) algorithm, and apply it in estimating the unknown parameters of chaotic dynamic systems. The principle and procedure of DPSO are presented, and the algorithm is used to identify Lorenz system and Chen system. The experiment results show that for the given parameter configurations, DPSO can identify the parameters of the systems accurately and effectively, and it may be a promising tool for chaotic system identification as well as other numerical optimization problems in physics. [Copyright &y& Elsevier]

Abstract: Two amphiphilic chiral receptors 2a and 2b were designed and synthesized. Both are efficient chiral solvating agents for chiral carboxylic acids. In particular, 2a is an excellent CSA not only for lipophilic guests, but also for some hydrophilic guests. It is the first CSA for the direct determination of the enantiomeric composition of hydrophilic chiral hydroxylated acid in protic polar solvent. [Copyright &y& Elsevier]

The enantioselectivity of chiral macrocyclic polyamides 1 – 3 derived from L-/D-tartaric acid was investigated by using 1 H NMR. All the macrocycles exhibited certain chiral recognition towards the enantiomers of the racemic carboxylic acids we had chosen. As a chiral solvating agent, the compound 3 has the excellent enantiomeric discriminating ability for mandelic acids and its derivatives, containing an α-OH at the chiral carbon, while the compound 2 has the best enantioselectivity towards dibenzoyltartaric acid. The molar ratio and the association constants of the compound 3 with each of the enantiomers of some guest molecules were determined by using the Job's plots and a nonlinear leastsquares fitting method, respectively. The effect of the structure of the hosts or guests on the enantioselectivity of the compound 1 – 3 has been explored. [ABSTRACT FROM AUTHOR]

Abstract: p-tert-Calix[6]-1,4-2,5-biscrown-4 was subjected to functionalization by benzyl bromide or ethyl bromoacetate. Two pairs of disubstituted calix[6]biscrown stereoisomers were obtained. Their structures had been deduced from 1H NMR and ESI-MS (electrospray ionization mass spectroscopy). One of the bisethyloxycarbonylmethylated derivatives 3a was further investigated by X-ray crystallographic analysis. Two-phase extraction experiments indicated that bisethyloxycarbonylmethylated derivatives exhibited high Cs+/Na+ selectivity. By ESI-MS and 1H NMR experiments it was confirmed that 3a formed 1:1 complex with Cs+. [Copyright &y& Elsevier]

N-(2-Hydroxyl-3-trimethylammonio)-propyl chitosan chloride with varying degree of substitution (DS) and molecular weight (MW) were prepared using nucleophilic substitution reaction, the structure of the modified chitosan was discussed using IR, 13C NMR and 1H NMR spectroscopies. The results show that substitution reaction occurred at primary aliphatic amino group rather than hydroxyl group on chitosan under the reaction conditions. DS was influenced by the ratio of epoxide ring to chitosan. The retention-aid properties of quaternary chitosan for natural occurring CaCO3 fillers had been studied using adsorption and flocculation experiments. It was found that quaternary chitosan was almost completely adsorbed onto the surfaces of CaCO3 particles at the experimental dosage level. When DS of chitosan were same (93%), the complete surface coverage, which were determined by zeta potential measurements, of CaCO3 particles used in this work were 0.735 mg g-1, 0.826 mg l-1 and 0.953 mg g-1 for the quaternary salt with MW = 4.8 × 104, 11 × 104 and 19 × 104, respectively. The electrostatic attractive was expected to be the dominant driving forces for the adsorption. Compared with a commercial cationic starch, quaternary chitosan had a lower flocculation concentration and a higher flocculation performance. Further, the optimum flocculation concentration was decreased with the increasing DS, and the flocculation of CaCO3 dispersion was significantly affected by the molecular weight of quaternary chitosan. The optimum flocculation concentrations were about 4, 5 and 6 mg l-1 for the quaternary chitosan with MW = 19 × 104, 11 × 104 and 4.8 × 104, respectively. It was also shown that the CaCO3 flocculation induced by the adsorption of quaternary chitosan was dominated by a charge patch mechanism. [Copyright &y& Elsevier]

Background: Colorectal cancer liver metastases (CRLM) has not been identified as a unified disease entity due to the differences in the severity of metastatic disease and tumor aggressiveness. A screen for specific prognostic risk subgroups is urgently needed. The current study aimed to investigate the prognostic value of DNA ploidy, stroma fraction and nucleotyping of initially resectable liver metastases from patients with CRLM. Methods: One hundred thirty-nine consecutive patients with initially resectable CRLM who underwent curative liver resection from 2006 to 2018 at Sun Yat-sen University Cancer Center were selected for analysis. DNA ploidy, stroma fraction and nucleotyping of liver metastases were evaluated using automated digital imaging systems. Recurrence-free survival (RFS) and overall survival (OS) were analyzed using the Kaplan-Meier method and Cox regression models. Results: DNA ploidy was identified as an independent prognostic factor for RFS (HR, 2.082; 95% CI 1.053–4.115; P = 0.035) in the multivariate analysis, while stroma-tumor fraction and nucleotyping were not significant prognostic factors. A significant difference in 3-year RFS was observed among the low-, moderate- and high-risk groups stratified by a novel parameter combined with the tumor burden score (TBS) and DNA ploidy (72.5% vs. 63.2% vs. 37.3%, P = 0.007). The high-risk group who received adjuvant chemotherapy had a significantly better 3-year RFS rate than those without adjuvant chemotherapy (46.7% vs. 24.8%; P = 0.034). Conclusions: Our study showed that DNA ploidy of liver metastases is an independent prognostic factor for patients with initially resectable CRLM after liver resection. The combination of DNA ploidy and TBS may help to stratify patients into different recurrence risk groups and may guide postoperative treatment among the patients. [ABSTRACT FROM AUTHOR]

Among adult-onset motor neuron diseases, amyotrophic lateral sclerosis (ALS) is the most common. ALS involves the increasing loss of lower and upper motor neurons. Within a few years of onset, ALS causes patient death via progressive paralysis of respiratory muscles. However, the current drugs used to treat ALS, riluzole, edaravone, and dextromethorphan/quinidine, can only delay the progression of the disease and alleviate a small number of symptoms in some patients, and no completely effective treatment is available. Traditional Chinese medicine (TCM) has shown significant advantages in the treatment of ALS in China and Asia; however, the mechanism of its efficacy is unclear. This review discusses the pathogenetic hypothesis of ALS in detail from the level of neurons and glial cells and uses two current experimental animal models of ALS to design experimental strategies to study TCM treatment. We aim to provide a scientific explanation of the mechanism of the effect of TCM in the treatment of ALS, which will help clinicians and research scientists to accept the theory of TCM to treat ALS and promote the development of TCM modernization. [ABSTRACT FROM AUTHOR]

Prolyl-4-hydroxylase subunit 2 (P4HA2) is a member of collagen modification enzymes involved in the remodeling of the extracellular matrix (ECM). Mounting evidence has suggested that deregulation of P4HA2 is common in cancer. However, the role of P4HA2 in glioma remains unknown. The present study aimed to elucidate the expression pattern, oncogenic functions, and molecular mechanisms of P4HA2 in glioblastoma cells. The TCGA datasets and paraffin samples were used for examining the expressions of P4HA2. P4HA2-specific lentivirus was generated to assess its oncogenic functions. A P4HA2 enzyme inhibitor (DHB) and an AKT agonist (SC79) were utilized to study the mechanisms. As a result, we demonstrated that P4HA2 is overexpressed in glioma and inversely correlates with patient survival. Knockdown of P4HA2 inhibited proliferation, migration, invasion, and epithelial-to-mesenchymal transition (EMT) like phenotype of glioma cells in vitro and suppressed tumor xenograft growth in vivo. Mechanistically, expressions of a series of collagen genes and of phosphorylated PI3K/AKT were downregulated by either P4HA2 silencing or inhibition of its prolyl hydroxylase. Finally, the inhibitory effects on the migration, invasion, and EMT-related molecules by P4HA2 knockdown were reversed by AKT activation with SC79. Our findings for the first time reveal that P4HA2 acts as an oncogenic molecule in glioma malignancy by regulating the expressions of collagens and the downstream PI3K/AKT signaling pathway. [ABSTRACT FROM AUTHOR]

Invariant natural killer T cells (iNKT) are a prevalent population of innate-like T cells in mice, but quite rare in humans that are critical for regulation of the innate and adaptive immune responses during antimicrobial immunity, tumor rejection, and inflammatory diseases. Multiple transcription factors and signaling molecules that contribute to iNKT cell selection and functional differentiation have been identified. However, the full molecular network responsible for regulating and maintaining iNKT populations remains unclear. MicroRNAs (miRNAs) are an abundant class of evolutionarily conserved, small, non-coding RNAs that regulate gene expression post-transcriptionally. Previous reports uncovered the important roles of miRNAs in iNKT cell development and function using Dicer mutant mice. In this review, we discuss the emerging roles of individual miRNAs in iNKT cells reported by our group and other groups, including miR-150, miR-155, miR-181, let-7, miR-17 ~ 92 cluster, and miR-183-96-182 cluster. It is likely that iNKT cell development, differentiation, homeostasis, and functions are orchestrated through a multilayered network comprising interactions among master transcription factors, signaling molecules, and dynamically expressed miRNAs. We provide a comprehensive view of the molecular mechanisms underlying iNKT cell differentiation and function controlled by dynamically expressed miRNAs. [ABSTRACT FROM AUTHOR]

Objectives: To compare the occurrence of emptying dysfunction between surgical techniques for orthotopic neobladder suspended with round ligament (rONB) and the standard procedure (sONB). Patients and Methods: A prospective randomised controlled trial was performed in a single centre of female patients undergoing creation of an ONB using rONB or sONB. Patients were followed for ≥24 months after ONB. The primary endpoints were significant post‐void residual urine volume (sPVR) and need for clean intermittent catheterisation (CIC) at 24 months postoperatively. The secondary endpoints included early and late complications, urodynamic profile, and ONB continence. Results: Between January 2011 and October 2017, the trial enrolled 85 patients, of whom 82 were randomised. A total of 41 patients had a rONB and 41 a sONB. At 24 months, 17 of the 37 patients with a sONB and nine of the 39 patients with a rONB had a sPVR. The cumulative risk of a sPVR was significantly lower in the rONB group (23.1%) vs the sONB group (45.9%) (hazard ratio [HR] 0.43, 95% confidence interval [CI], 0.19–0.96; P = 0.040). In all, 15 of the 37 patients with a sONB and four of the 39 patients with a rONB needed CIC. The cumulative risk of requiring CIC was significantly lower in the rONB group (10.3%) vs the sONB group (40.5%) (HR 0.22, 95% CI 0.07–0.67; P = 0.008) at 24 months. Multivariable Cox regression analysis also showed that the rONB type was an independently protective factor for sPVR and CIC. The rates of early (0–90 days) and late complication (>90 days) were 54.1% and 13.5% in the sONB group, and 64.1% and 10.3% in the rONB group, respectively. There were no significant differences in complications, urodynamic profile or ONB continence. A major limitation is the small sample size at a single centre. Conclusion: Posterior support with round ligament for an ONB significantly improved the emptying of the ONB and resulted in a reduced need for CIC. The surgical modification is a feasible and safe technique without additional complication‐related surgeries. [ABSTRACT FROM AUTHOR]

Plasticised poly(vinyl chloride) optode membrane incorporated with nonactin as ionophore, ETH 5294 as H+-selective chromoionophore and potassium tetrakis(4-chlorophenyl)borate as anionic site, was used as a reversible sensing device for indirect determination of nicotine. Nicotine was extracted from cigarette samples and converted to its bromoethane derivative (ND+Br−) by reacting with a solution of bromoethane in ethanol. ND+Br−, in a solution of Tris (hydroxymethyl)aminomethane–HCl buffer, was extracted into the bulk of the optode membrane and subsequently caused changes in optical absorption of the sensing layer. The pH effect, response mechanisms, response behaviour, response time, dynamic working range, detection limit, sensitivity and selectivity were discussed in detail. [Copyright &y& Elsevier]

[Display omitted] Amidst the development of photoelectrochemical (PEC) CO 2 conversion toward practical application, the production of high-value chemicals beyond C 1 compounds under mild conditions is greatly desired yet challenging. Here, through rational PEC device design by combining Au-loaded and N-doped TiO 2 plate nanoarray photoanode with Zn-doped Cu 2 O dark cathode, efficient conversion of CO 2 to CH 3 COOH has been achieved with an outstanding Faradaic efficiency up to 58.1% (91.5% carbon selectivity) at 0.5 V vs. Ag/AgCl. Temperature programmed desorption and in situ Raman spectra reveal that the Zn-dopant in Cu 2 O plays multiple roles in selective catalytic CO 2 conversion, including local electronic structure manipulation and active site modification, which together promote the formation of intermediate *CH 2 /*CH 3 for C–C coupling. Apart from that, it is also unveiled that the sufficient electron density provided by the Au-loaded and N-doped TiO 2 plate nanoarray photoanode plays an equally important role by initiating multi-electron CO 2 reduction. This work provides fresh insights into the PEC system design to reach the multi-electron reduction reaction and facilitate the C–C coupling reaction toward high-value multicarbon (C 2+) chemical production via CO 2 conversion. [ABSTRACT FROM AUTHOR]

To avoid the energy‐consuming step of direct N≡N bond cleavage, photocatalytic N2 fixation undergoing the associative pathways has been developed for mild‐condition operation. However, it is a fundamental yet challenging task to gain comprehensive understanding on how the associative pathways (i.e., alternating vs. distal) are influenced and altered by the fine structure of catalysts, which eventually holds the key to significantly promote the practical implementation. Herein, we introduce Fe dopants into TiO2 nanofibers to stabilize oxygen vacancies and simultaneously tune their local electronic structure. The combination of in situ characterizations with first‐principles simulations reveals that the modulation of local electronic structure by Fe dopants turns the hydrogenation of N2 from associative alternating pathway to associative distal pathway. This work provides fresh hints for rationally controlling the reaction pathways toward efficient photocatalytic nitrogen fixation. [ABSTRACT FROM AUTHOR]

To avoid the energy‐consuming step of direct N≡N bond cleavage, photocatalytic N2 fixation undergoing the associative pathways has been developed for mild‐condition operation. However, it is a fundamental yet challenging task to gain comprehensive understanding on how the associative pathways (i.e., alternating vs. distal) are influenced and altered by the fine structure of catalysts, which eventually holds the key to significantly promote the practical implementation. Herein, we introduce Fe dopants into TiO2 nanofibers to stabilize oxygen vacancies and simultaneously tune their local electronic structure. The combination of in situ characterizations with first‐principles simulations reveals that the modulation of local electronic structure by Fe dopants turns the hydrogenation of N2 from associative alternating pathway to associative distal pathway. This work provides fresh hints for rationally controlling the reaction pathways toward efficient photocatalytic nitrogen fixation. [ABSTRACT FROM AUTHOR]

Aqueous sodium–zinc hybrid ion batteries are attracting extensive attention due to high energy density, low cost, and environmental friendliness. Unfortunately, there are still some drawbacks associated with the low voltage and cycle performance degradation that limit their practical application. Here, a concentrated aqueous electrolyte with solvation‐modulated Zn2+ is reported that reduces the hydrogen evolution reaction on the surface of Zn metal, avoiding the generation of ZnO and uneven deposition. Accordingly, the Zn anode exhibits 1600 h Zn plating/stripping and ≈99.96% Coulombic efficiency after 700 cycles. In addition, solvation‐modulated Na+ promotes the excellent structural stability of zinc hexacyanoferrate (ZnHCF) due to the rhombohedral–rhombohedral rather than rhombohedral–cubic phase transition. A ZnHCF//Zn full cell delivers an average voltage of 1.76 V and 98% capacity retention after 2000 cycles at 5 C rates. [ABSTRACT FROM AUTHOR]

Subsurface migration and accumulation of oil and gas have interested researchers for a long time, but these processes may occur over very long geological periods and are difficult to observe directly, so experimental simulations are warranted. In this study, an experimental method was developed to model hydrocarbon migration in the subsurface structure. Oil migration was simulated in a sandbox model, and industrial CT scanning was used to observe both the internal geometry of the model and the oil migration pathways. In the sandbox model, a NaI solution was used to simulate water, white oil was used to simulate hydrocarbon, and fine quartz sand, glass bead, silica powder, and brown corundum were chosen to represent brittle crust, based on suitable material parameters. A NaI-saturated layered sandbox model was constructed with an along-strike basal discontinuity, which during compression allowed a simple anticline with doubly verging reverse faults to form. Oil was then released continuously at a low rate from an orifice under one limb of the anticline. Initially, the oil migrated vertically through the fault zone until it reached the top of the fault zone; it then migrated laterally along the core of the anticline, saturating a model reservoir by buoyancy and capillary force. This experimental analog helps to explain hydrocarbon migration and accumulation within the Anjihai and Santai anticlines in northwest China. [ABSTRACT FROM AUTHOR]

Tool wear is a key factor that dominates the surface quality and distinctly influences the generated workpiece surface texture. In order to realize accurate evaluation of the tool wear from the generated workpiece surface after machining process, a new tool wear monitoring method is developed by fractal dimension of the acquired workpiece surface digital image. A self-made simple apparatus is employed to capture the local digital images around the region of interest. In addition, a skew correction method based on local fast Fourier transformation energy is also proposed for the surface texture direction adjustment. Furthermore, the tool wear quantitative evaluation was derived based on fractal dimension utilizing its high reliability for inherent irregularity description. The proposed tool wear monitoring method has verified its feasibility as well as its effectiveness in actual milling experiments using the material of AISI 1045 in a vertical machining center. Testing results demonstrate that the proposed method was capable of tool wear condition evaluation. [ABSTRACT FROM AUTHOR]

Low‐temperature solution‐processed TiO2 nanocrystals (LT‐TiO2) have been extensively applied as electron transport layer (ETL) of perovskite solar cells (PSCs). However, the low electron mobility, high density of electronic trap states, and considerable photocatalytic activity of TiO2 result in undesirable charge recombination at the ETL/perovskite interface and notorious instability of PSCs under ultraviolet (UV) light. Herein, LT‐TiO2 nanocrystals are in situ fluorinated via a simple nonhydrolytic method, affording formation of Ti─F bonds, and consequently increase electron mobility, decrease density of electronic trap states, and inhibit photocatalytic activity. Upon applying fluorinated TiO2 nanocrystals (F‐TiO2) as ETL, regular‐structure planar heterojunction PSC (PHJ‐PSC) achieves a champion power conversion efficiency (PCE) of 22.68%, which is among the highest PCEs for PHJ‐PSCs based on LT‐TiO2 ETLs. Flexible PHJ‐PSC devices based on F‐TiO2 ETL exhibit the best PCE of 18.26%, which is the highest value for TiO2‐based flexible devices. The bonded F atoms on the surface of TiO2 promote the formation of Pb─F bonds and hydrogen bonds between F− and FA/MA organic cations, reinforcing interface binding of perovskite layer with TiO2 ETL. This contributes to effective passivation of the surface trap states of perovskite film, resulting in enhancements of device efficiency and stability especially under UV light. [ABSTRACT FROM AUTHOR]

Background: Precise methods for postoperative risk stratification to guide the administration of adjuvant chemotherapy (ACT) in localized colorectal cancer (CRC) are still lacking. Here, we conducted a prospective, observational, and multicenter study to investigate the utility of circulating tumor DNA (ctDNA) in predicting the recurrence risk. Methods: From September 2017 to March 2020, 276 patients with stage II/III CRC were prospectively recruited in this study and 240 evaluable patients were retained for analysis, of which 1290 serial plasma samples were collected. Somatic variants in both the primary tumor and plasma were detected via a targeted sequencing panel of 425 cancer-related genes. Patients were treated and followed up per standard of care. Results: Preoperatively, ctDNA was detectable in 154 of 240 patients (64.2%). At day 3–7 postoperation, ctDNA positivity was associated with remarkably high recurrence risk (hazard ratio [HR], 10.98; 95%CI, 5.31–22.72; P < 0.001). ctDNA clearance and recurrence-free status was achieved in 5 out of 17 ctDNA-positive patients who were subjected to ACT. Likewise, at the first sampling point after ACT, ctDNA-positive patients were 12 times more likely to experience recurrence (HR, 12.76; 95%CI, 5.39–30.19; P < 0.001). During surveillance after definitive therapy, ctDNA positivity was also associated with extremely high recurrence risk (HR, 32.02; 95%CI, 10.79–95.08; P < 0.001). In all multivariate analyses, ctDNA positivity remained the most significant and independent predictor of recurrence-free survival after adjusting for known clinicopathological risk factors. Serial ctDNA analyses identified recurrence with an overall accuracy of 92.0% and could detect disease recurrence ahead of radiological imaging with a mean lead time of 5.01 months. Conclusions: Postoperative serial ctDNA detection predicted high relapse risk and identified disease recurrence ahead of radiological imaging in patients with stage II/III CRC. ctDNA may be used to guide the decision-making in postsurgical management. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Green plants and algae utilize complicated yet delicate structures to oxidize water into molecular oxygen while releasing electrons for dark reactions. The photocatalytic water oxidation reaction in photosystem II is challenging as it involves in transferring multiple electrons and protons and requires a large overpotential. Herein, for the first time, we report that conjugated ladder polymers with suitable band structures are potential metal‐free photocatalysts for efficient and stable water oxidation. Two structurally similar conjugated ladder polymers are synthesized via the condensation reaction between amine‐ and ketone‐containing monomers. Photocatalytic tests reveal that different polymer structures exhibit different photocatalytic performances which are determined by their inherent optoelectronics properties. Meanwhile, our first‐principles calculations confirm that photocatalytic water oxidation is thermodynamically feasible for both conjugated ladder polymers under visible light irradiation. Our study unveils a novel class of polymer materials for the water oxidation reaction and further indicates that metal‐free photocatalysts hold great potential for future solar‐to‐chemical conversion. [ABSTRACT FROM AUTHOR]

Low‐temperature solution‐processed TiO2 nanocrystals (LT‐TiO2) have been extensively applied as electron transport layer (ETL) of perovskite solar cells (PSCs). However, the low electron mobility, high density of electronic trap states, and considerable photocatalytic activity of TiO2 result in undesirable charge recombination at the ETL/perovskite interface and notorious instability of PSCs under ultraviolet (UV) light. Herein, LT‐TiO2 nanocrystals are in situ fluorinated via a simple nonhydrolytic method, affording formation of Ti─F bonds, and consequently increase electron mobility, decrease density of electronic trap states, and inhibit photocatalytic activity. Upon applying fluorinated TiO2 nanocrystals (F‐TiO2) as ETL, regular‐structure planar heterojunction PSC (PHJ‐PSC) achieves a champion power conversion efficiency (PCE) of 22.68%, which is among the highest PCEs for PHJ‐PSCs based on LT‐TiO2 ETLs. Flexible PHJ‐PSC devices based on F‐TiO2 ETL exhibit the best PCE of 18.26%, which is the highest value for TiO2‐based flexible devices. The bonded F atoms on the surface of TiO2 promote the formation of Pb─F bonds and hydrogen bonds between F− and FA/MA organic cations, reinforcing interface binding of perovskite layer with TiO2 ETL. This contributes to effective passivation of the surface trap states of perovskite film, resulting in enhancements of device efficiency and stability especially under UV light. [ABSTRACT FROM AUTHOR]

x Ta-PNN-PZT piezoelectric ceramics with [0.55 Pb(Ni 1/3 Nb 2/3)O 3 - 0.45 Pb(Zr 0.3 Ti 0.7)O 3 - x wt%Ta 2 O 5 ] + 1 wt% PbO composition (0 ≤ x ≤ 0.7) were prepared by conventional solid-state reaction method. Special attention was paid to the effect of Ta 2 O 5 concentration on structural, dielectric, piezoelectric, and ferroelectric properties of these ceramics. In particular, rhombohedral-tetragonal morphotropic phase boundary was observed in PNN-PZT crystal structure near the composition of x = 0.5. At this point, volume fraction of rhombohedral phase was almost equal to that of tetragonal phase. In addition, the ceramic exhibited the optimum values of piezoelectric coefficient, bipolar strain, unipolar strain, and inverse piezoelectric coefficient, i.e., 1090 pC/N, 0.135%, 0.165%, and 1493 pm/V, respectively. Moreover, according to in-situ X-ray diffraction, piezoelectric force microscopy, and in-situ strain measurement results, phase structure of 0.5Ta-PNN-PZT revealed relatively stable piezoelectric behavior at 60 °C. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) conversion of methane (CH4) has been extensively explored for the production of value‐added chemicals, yet remains a great challenge in high selectivity toward C2+ products. Herein, we report the optimization of the reactivity of hydroxyl radicals (.OH) on WO3 via facet tuning to achieve efficient ethylene glycol production from PEC CH4 conversion. A combination of materials simulation and radicals trapping test provides insight into the reactivity of.OH on different facets of WO3, showing the highest reactivity of surface‐bound.OH on {010} facets. As such, the WO3 with the highest {010} facet ratio exhibits a superior PEC CH4 conversion efficiency, reaching an ethylene glycol production rate of 0.47 μmol cm−2 h−1. Based on in situ characterization, the methanol, which could be attacked by reactive.OH to form hydroxymethyl radicals, is confirmed to be the main intermediate for the production of ethylene glycol. Our finding is expected to provide new insight for the design of active and selective catalysts toward PEC CH4 conversion. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) conversion of methane (CH4) has been extensively explored for the production of value‐added chemicals, yet remains a great challenge in high selectivity toward C2+ products. Herein, we report the optimization of the reactivity of hydroxyl radicals (.OH) on WO3 via facet tuning to achieve efficient ethylene glycol production from PEC CH4 conversion. A combination of materials simulation and radicals trapping test provides insight into the reactivity of.OH on different facets of WO3, showing the highest reactivity of surface‐bound.OH on {010} facets. As such, the WO3 with the highest {010} facet ratio exhibits a superior PEC CH4 conversion efficiency, reaching an ethylene glycol production rate of 0.47 μmol cm−2 h−1. Based on in situ characterization, the methanol, which could be attacked by reactive.OH to form hydroxymethyl radicals, is confirmed to be the main intermediate for the production of ethylene glycol. Our finding is expected to provide new insight for the design of active and selective catalysts toward PEC CH4 conversion. [ABSTRACT FROM AUTHOR]

Purpose: Colorectal cancer (CRC) rarely occurs in children and adolescents. This study aimed to perform a retrospective analysis and disclose more detailed information about CRC in patients under 20 years old. Methods: Medical records of CRCs in patients under 20 years old referred to three tertiary hospitals in China from September 2000 to July 2019 were retrospectively reviewed. Clinicopathological characteristics, treatment processes and laboratory findings were summarized and treatment outcomes and prognostic factors were analyzed. Results: A total of 33,394 CRC medical records were analyzed, and we identified seventy (0.21%) CRCs in patients under 20. The most common primary tumor location was the left hemicolon (35.7%). The prominent pathological types were mucinous adenocarcinoma (22.9%) and signet ring cell carcinoma (22.9%). Nearly half (47.1%) of the patients presented with distant metastasis at diagnosis. The fractions of patients with deficient mismatch repair (dMMR) protein expression and microsatellite instability-high (MSI-H) were 23.8% (5/21) and 71.4% (5/7), respectively. Forty-four patients underwent radical surgery. Fifty-five patients received chemotherapy and six patients received radiotherapy. One dMMR/MSI-H rectal cancer patient received immunotherapy and achieved a clinically complete response. The median overall survival (OS) time was 80 months. The 3-year and 5-year OS rates were 61.8% and 57.2%, respectively. An absence of distant metastasis was a favorable factor for OS. For stage II/III CRCs, classic adenocarcinoma and radical surgery were favorable factors for OS. For stage IV CRCs, primary location at the colon was a favorable factor for OS. Conclusion: Child and adolescent CRC patients are likely to have distant metastasis, undifferentiated, left hemicolon location, and a dMMR/MSI-H phenotype at diagnosis. Additional efforts are needed to improve their survival outcomes. [ABSTRACT FROM AUTHOR]

[Display omitted] Broadly, the oxygen evolution reaction (OER) has been deeply understood as a significant part of energy conversion and storage. Nevertheless, the anions in the OER catalysts have been neglected for various reasons such as inactive sites, dissolution, and oxidation, amongst others. Herein, we applied a model catalyst s-Ni(OH) 2 to track the anionic behavior in the catalyst during the electrochemical process to fill this gap. The advanced operando synchrotron radiation Fourier transform infrared (SR-FTIR) spectroscopy, synchrotron radiation photoelectron spectroscopy (SRPES) depth detection and differential X-ray absorption fine structure (Δ-XAFS) spectrum jointly point out that some oxidized sulfur species (SO 4 2−) will self-optimize new Ni–S bonds during OER process. Such amazing anionic self-optimization (ASO) behavior has never been observed in the OER process. Subsequently, the optimization-derived component shows a significantly improved electrocatalytic performance (activity, stability, etc.) compared to reference catalyst Ni(OH) 2. Theoretical calculation further suggests that the ASO process indeed derives a thermodynamically stable structure of the OER catalyst, and then gives its superb catalytic performance by optimizing the thermodynamic and kinetic processes in the OER, respectively. This work demonstrates the vital role of anions in the electrochemical process, which will open up new perspectives for understanding OER and provide some new ideas in related fields (especially catalysis and chemistry). [ABSTRACT FROM AUTHOR]

Recently emerging spintronic terahertz (THz) emitters, featuring many appreciable merits such as low-cost, high efficiency, ultrabroadband, and ease of integration, offer multifaceted capabilities not only in understanding the fundamental ultrafast magnetism physics but also for exploring multifarious practical applications. Integration of various flexible and tunable functions at the source such as polarization manipulation, amplitude tailoring, phase modulation, and radiation beam steering with the spintronic THz emitters and their derivatives can yield more compact and elegant devices. Here, we demonstrate a monolithic metamaterial integrated onto a W/CoFeB/Pt THz nanoemitter for a purpose-designed functionality of the electromagnetically induced transparency analog. Through elaborate engineering the asymmetry degree and geometric parameters of the metamaterial structure, we successfully verified the feasibility of monolithic modulations for the radiated THz waves. The integrated device was eventually compared with a set of stand-alone metamaterial positioning scenarios, and the negligible frequency difference between two of the positioning schemes further manifests almost an ideal realization of the proposed monolithic integrated metamaterial device with a spintronic THz emitter. We believe that such adaptable and scalable devices may make valuable contributions to the designable spintronic THz devices with pre-shaping THz waves and enable chip-scale spintronic THz optics, sensing, and imaging. [ABSTRACT FROM AUTHOR]

Free‐space super‐strong terahertz (THz) electromagnetic fields offer multifaceted capabilities for reaching extreme nonlinear THz optics. However, the lack of powerful solid‐state THz sources with single pulse energy >1 mJ is impeding the proliferation of extreme THz applications. The fundamental challenge lies in hard to achieve high efficiency due to high intensity pumping caused crystal damage, linear absorption, and nonlinear distortion induced short effective interaction length, and so on. Here, through cryogenically cooling the crystals, tailoring the pump laser spectra, chirping the pump pulses, and magnifying the laser energies, 1.4‐mJ THz pulses are successfully realized in lithium niobates under the excitation of 214‐mJ femtosecond laser pulses via tilted pulse front technique. The 800 nm‐to‐THz energy conversion efficiency reaches 0.7%, and a free‐space THz peak electric and magnetic field reaches 6.3 MV cm−1 and 2.1 Tesla. Numerical simulations reproduce the experimental optimization processes. To show the capability of this super‐strong THz source, nonlinear absorption in high conductive silicon induced by strong THz electric field is demonstrated. Such a high‐energy THz source with a relatively low peak frequency is very appropriate not only for electron acceleration toward table‐top X‐ray sources but also for extreme THz science and nonlinear applications. [ABSTRACT FROM AUTHOR]

Terahertz (THz) modulators offer multifaceted capabilities for various practical applications such as THz imaging, wireless communications, sensing, etc. However, compared to the modulation devices used for other electromagnetic bands, the ubiquitous proliferation of THz applications is severely impeded by the tremendous lack of complementary metal-oxide-semiconductor (CMOS)-compatible technology. Here we demonstrated a CMOS-based active tunable THz metamaterial array (C-ATTMA) with split-ring resonators (SRRs). The THz metamaterial can be externally controlled with an electrically controlled dynamic. The C-ATTMA fabricated by the 180 nm CMOS technology featuring a resonant frequency of 0.30 THz was connected to the source and drain of a bottom metal-oxide-semiconductor field-effect transistor (MOSFET) through the vias. By delicately controlling the MOSFET gate voltage, the equivalent circuit response of the C-ATTMA was actively engineered, enabling tailoring THz resonance frequencies. Under a gate voltage of 1.8 V, we successfully realized a resonant frequency shift of ∼35 GHz and 3° phase shift. The equivalent circuit successfully explained the principle of the change. Inductor–capacitor (LC) resonance and electric dipole resonance of single-layer and double-layer SRRs have also been studied. The exhibited CMOS-compatible electrically regulated THz metamaterials provided a potential method for voltage regulation of THz, which may contribute to THz wireless communications, information encryption, THz compressed sensing and imaging, etc. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic caused by the novel SARS-CoV-2 is more contagious than other coronaviruses and has higher rates of mortality than influenza. Identification of effective therapeutics is a crucial tool to treat those infected with SARS-CoV-2 and limit the spread of this novel disease globally. We deployed a bioinformatics workflow to identify candidate drugs for the treatment of COVID-19. Using an "omics" repository, the Library of Integrated Network-Based Cellular Signatures (LINCS), we simultaneously probed transcriptomic signatures of putative COVID-19 drugs and publicly available SARS-CoV-2 infected cell lines to identify novel therapeutics. We identified a shortlist of 20 candidate drugs: 8 are already under trial for the treatment of COVID-19, the remaining 12 have antiviral properties and 6 have antiviral efficacy against coronaviruses specifically, in vitro. All candidate drugs are either FDA approved or are under investigation. Our candidate drug findings are discordant with (i.e., reverse) SARS-CoV-2 transcriptome signatures generated in vitro, and a subset are also identified in transcriptome signatures generated from COVID-19 patient samples, like the MEK inhibitor selumetinib. Overall, our findings provide additional support for drugs that are already being explored as therapeutic agents for the treatment of COVID-19 and identify promising novel targets that are worthy of further investigation. [ABSTRACT FROM AUTHOR]

Most biological photoredox reactions occur in sophisticated molecular assemblies consisting of highly organized light-harvesting moieties and catalytic centers. Mimicking these prototypes by creating supramolecular assemblies could be a potentially viable approach toward artificial photosynthesis. Although self-assembled organic materials are known to carry out water splitting reactions, developing self-assembled organic materials for photocatalytic overall water splitting still remains a critical challenge. Herein, we first demonstrate that crystalline organic nanosheets assembled from linear oligo(phenylene butadiynylene) (OPB) are able to catalyze overall water splitting under visible light irradiation. Further investigations reveal that the photocatalytic activity of self-assembled organic structures is closely related to the crystalline structure along with the corresponding electronic structure. Structural disorders in OPB nanosheets and extrinsic factors such as adsorbed water molecules will induce the formation of electron traps which can make the OPB nanosheets thermodynamically unfavorable for photocatalytic overall water splitting. The deactivation mechanism unveiled in this study provides crucial insights into the assembling of artificial organic materials for future solar-to-chemical energy conversion. [ABSTRACT FROM AUTHOR]