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Sensing the spin states of circularly polarized light (CPL) is a prerequisite for varied advanced applications. Here, we show that a Rashba-Dresselhaus (RD) spin-splitting mechanism is responsible for detecting CPL in noncentrosymmetric semiconductors. In ferroelectric (2FPMA)2PbBr4(2FPMA = 2-fluorobenzylammonium), the polar structure and strong spin-orbit coupling trigger a large RD spin splitting that differentiates CPL-excited carriers in the momentum space via optical transition selection rules. A single-crystal-based device shows a comparable detection performance to sense CPL spin states with an asymmetric factor of 0.37. Furthermore, the electrical reversal of the ferroelectric polarization leads to switchable bulk photovoltaic effect and spin texture, enabling self-powered and tunable photodetection. This indicates the validity of the RD spin-splitting mechanism in directly sensing CPL spin states without the need for chirality, thereby expanding the research scope of electrically switchable spin-responsive materials.

A two-dimensional (2D) organic–inorganic hybrid perovskite (OIHP) material with out-of-plane ferroelectricity is the key to the miniaturization of vertical-sandwich-type ferroelectric optoelectronic devices. However, 2D OIHP ferroelectrics with out-of-plane polarization are still scarce, and effective design strategies are lacking. Herein, we report a novel 2D Dion–Jacobson perovskite ferroelectric semiconductor synthesized by a rigid-to-flexible cationic tailoring strategy, achieving an out-of-plane polarization of 1.7 μC/cm2and high photoresponse. Integrating out-of-plane ferroelectricity with excellent photoelectric properties affords a promising platform to investigate ferroelectricity-related effects in vertical optoelectronic devices.

Multivariate real-life time series data often contain missing values. These missing values often affect subsequent prediction tasks. Traditional imputation methods generally consider only some of the characteristics of multivariate time series data. This can easily lead to inaccurate filling results. In this paper, a feature correlation-based bidirectional recurrent network (BRNN-FR) is proposed to solve the problem of missing values in multivariate sequence data. First, this method involves the design of a bidirectional prediction network based on time intervals and the use of forward and reverse time series information between data points to obtain the characteristics of data changes with time to the greatest extent. Second, considering the correlation between features, a combined feature selection strategy based on the Pearson correlation coefficient and mutual information was proposed. A multiple regression model was established to predict between features. Finally, a bidirectional network ensemble filling algorithm based on the relationships between features is established to predict missing values. Comprehensive experiments on four public datasets show that the mean absolute error (MAE), root mean square error (RMSE) and maximum R2 value (R2_score) of the BRNN-FR algorithm in the direct imputation test are better than those of the other comparison methods in most cases. BRNN-FR also achieved a better area under the curve (AUC) in the indirect comparison experiment of two classifications of in-hospital death after filling the medical dataset. Using the AIR air quality dataset and the power transformer temperature dataset from the ETTH1 interpolation regression to predict the next 3 hours and 6 hours of average numerical results, most of the optimal regression results are obtained. • This paper introduces a feature correlation based bidirectional recurrent network (BRNN-FR) model for handling missing values in multivariate sequence data. • It uses a bidirectional prediction network to capture temporal data changes with time to the greatest extent. A combined feature selection strategy based on Pearson correlation coefficient and mutual information is proposed. A multiple regression model predicts feature relationships. Finally, a bidirectional network ensemble filling algorithm completes the prediction of missing values. • The model outperforms other algorithms on four datasets, validating its effectiveness. [ABSTRACT FROM AUTHOR]

Hepatic hemangioma is a frequent nonmalignant tumor in the human liver. Although rupture of hepatic hemangioma is a rare complication, it may have serious consequences. In this report, we describe a 56-year-old woman who underwent laparoscopic surgery and open surgery for sudden abdominal pain and peritonitis. Gastrointestinal perforation was prioritized before surgery according to the patient’s symptoms, signs, and radiological report. A giant dark red mass connected to the left liver by a pedicle was unexpectedly found during intraoperative exploration. Hemoperitoneum was also found. Conversely, no gastrointestinal perforation was found during intraoperative exploration. The mass was successfully removed, and the hemoperitoneum was resolved. Postoperative pathological examination showed that the mass was a hepatic hemangioma. Ultimately, the patient was diagnosed with spontaneous rupture of a giant hepatic hemangioma.

Protein tyrosine O-sulfation is considered as the most common type of post-translational tyrosine modification in nature and plays important roles in extracellular biomolecular interactions. To facilitate the mapping, biological study, and medicinal application of this type of post-translational modification, we seek to evolve a small protein scaffold that recognizes sulfotyrosine with high affinity. We focused our efforts on the engineering of the Src Homology 2 (SH2) domain, which represents the largest class of known phosphotyrosine-recognition domain in nature and has a highly evolvable binding pocket. By using phage display, we successfully engineered the SH2 domain to recognize sulfotyrosine with high affinity. The best mutant, SH2-60.1, displayed more than 1700 fold higher sulfotyrosine-binding affinity than that of the wild-type SH2 domain. We also demonstrated that the evolved SH2 domain mutants could be used to detect sulfoprotein levels on the cell surface. These evolved SH2 domain mutants can be potentially applied to the study of protein tyrosine O-sulfation with proper experimental designs.

The enzyme UDP-glucose dehydrogenase (UGDH) catalyzes the reaction of UDP-glucose to UDP-glucuronate through two successive NAD+-dependent oxidation steps. Human UGDH apoprotein is purified as a mixture of dimeric and hexameric species. Addition of substrate and cofactor stabilizes the oligomeric state to primarily the hexameric form. To determine if the dynamic conformations of hUGDH are required for catalytic activity, we used site-specific unnatural amino acid incorporation to facilitate cross-linking of monomeric subunits into predominantly obligate oligomeric species. Optimal cross-linking was achieved by encoding p-benzoyl-l-phenylalanine at position 458, normally a glutamine located within the dimer–dimer interface, and exposing the enzyme to long wavelength ultraviolet (UV) radiation in the presence of substrate and cofactor. Hexameric complexes were purified by gel filtration chromatography and found to contain significant fractions of dimer and trimer (approximately 50%) along with another 10% higher-molecular mass species. The activity of the cross-linked enzyme was reduced by almost 60% relative to that of the un-cross-linked UGDH mutant, and UV exposure had no effect on the activity of the wild-type enzyme. These results support a model for catalysis in which the ability to dissociate the dimer–dimer interface is as important for maximal enzyme function as has been previously shown for the formation of the hexamer.

Nanosheets derived from two-dimensional covalent organic frameworks (2D COFs) are increasingly desirable in various fields. While breakthroughs in the chemical and physical delamination of 2D COFs are rising, precisely regulating the growth of the COF nanosheets has not been realized yet. Herein, we report an effective strategy of polymer-manipulated crystallization to accurately control the growth of COF nanosheets. Chemically asymmetric polyvinylpyrrolidone (PVP) is developed as the manipulator that selectively interacts with the aldehydes and (100) facet to induce anisotropic growth of COFs. The number of PVP constitutional units determines this specific interaction, leading to molecularly thin but thickness-controllable nanosheets with excellent dispersity. We process these nanosheets into robust A4-sized membranes for ultraselective molecular separation. The membrane intercalated with long-chain PVP demonstrates largely improved performance, surpassing the reported COF membranes. This work reports a strategy for anisotropically crystallizing 2D COFs to yield processable nanosheets toward practical applications.

Structural phase transitions in organic–inorganic hybrid perovskites offer the potential for controlling a wide range of physical properties. However, the rational design of phase-transition materials remains challenging in the relevant fields. In this study, we synthesized and characterized two one-dimensional (1D) perovskites: (4ATHP)PbI3(1; 4ATHP = 4-aminotetrahydropyran), featuring face-shared inorganic chains and (4AMTHP)6Pb5I16(H2O)2(2; 4AMTHP = 4-aminomethyltetrahydropyran), which contains rare mixed face-shared and edge-shared inorganic chains. Interestingly, despite the minor difference in the cation between 1and 2, solely defined by the length of the terminal group, 2shows phase-transition properties while 1does not. Crystal structure analysis and Hirshfeld surface analysis indicate that the phase transition arises from the ordered–disordered change of the cation’s terminal group and the weakening of the interactions between the cation and inorganic skeleton. In addition, compound 2exhibits rare biaxial negative thermal expansion behavior. These findings provide valuable insights into the expansion of functional phase-transition materials, offering a promising avenue for further design and development.

In this paper, we optimise a satellite TV antenna control system for car carrying by extracting AGC signal. AGC signal is used to be a reference signal and reflect the strength of signal received by antenna. With the help of AGC signal, tuner and demodulator allows control system to form a closed loop. Experimental results show that the method improves the accuracy of the antenna control system and optimises the performance of antenna control system.

This thesis presents a new approach to classify 3D surface textures by using lifting transform with quincunx subsampling. Feature vectors are generated from eight different lifting prediction directions. We classify 3D surface texture images based on minimum Euclidean distance between the test images and the training sets. The feasibility and effectiveness of our proposed approach can be validated by the experimental results.

Driveline gearbox includes transmission gearbox and rear axle,automotive gear oil used to lubricate gear.Take rear axle for example,through catia ,we can build three-dimensional models,and use ansa to mesh axle , then import it to fluid software fluent to analyze temperature,and obtain oil temperature curve under certain load over time;it can predict transmission efficiency and equilibrium temperature under a certain load ,and reduce gear wear and improve the operational reliability of the car.

When 7721 human hepatocarcinoma cells were treated with 100nmphorbol-12-myristate-13-acetate (PMA), the activity ofN-acetylglucosaminyltransferase V(GnT-V) in the cells varied in accordance with the activity of membranous protein kinase C (PKC), but not with that of cytosolic PKC. Quercetin, a non-specific inhibitor of Ser/Thr protein kinase, andd-sphingosine and staurosporine, two specific inhibitors of PKC, blocked the activation of membranous PKC and GnT-V by PMA. Among the three inhibitors, quercetin was least effective. The inhibitory rates of quercetin and staurosporine toward membranous PKC and GnT V were proportional to the concentrations of the two inhibitors. The activities of GnT V and membranous protein kinase A (PKA) were also induced in parallel by dibutyryl cAMP (db-cAMP) and this induction was blocked by a specific PKA inhibitor. When cell free preparations of 7721 cells and human kidney were treated with alkaline phosphatase (ALP) to remove the phosphate groups, the GnT V activities were decreased. These results suggest that GnT V may be activated by membranous PKC or PKA, indirectly or directly, via phosphorylation of Ser/Thr residues.

In order to study the effect of retinoic acid on the structure of N-glycans on the cell surface, the N-glycans of glycoproteins on the surface of 7721 human hepatocarcinoma cells were labelled with [3H] mannose, added to the culture medium. The3H-labelled N-glycans were prepared from cell-surface glycoproteins, desialylated, and subjected to sequential chromatography on concanavalin A andDatura stranonium agglutinin affinity columns to separate the glycans into four fractions of different type and different antennary number. It was found that the percentage of C2C2 biantennary complex type N-glycans was increased, but the high-mannose type as well as the triand tetraantennary complex types, especially that with a C2,6 branched structure, were decreased after the cells had been treated with retinoic acid for 3–5 days. Using aLens culinaris agglutinin affinity column, it was discovered that the core fucose in the biantennary glycan was also decreased. The enzymatic mechanisms of the above changes were revealed in further study to involve the decrease ofN-acetylglucosaminul-transferase V and core a-1,6-fucosyltransferase.

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