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Abstract 2-dimensional (2D) piezoelectric materials have gained significant attention due to their potential applications in flexible energy harvesting and storage devices. Recently, niobium oxide dihalides NbOI2 stands out as a multifunctional anisotropic semiconductor family with an exceptionally high lateral piezoelectric constant (~21.8 pm/V), making it a promising candidate for energy conversion applications. Here we report the experimental observation of anisotropic in-plane piezoelectricity in multilayer NbOI2. Current-voltage relationships reveal a significant piezotronic effect in two typical crystalline orientations. Additionally, cyclic tensile and release experiments demonstrate an intrinsic current output of up to 140 pA when subjected to a tensile strain of 0.51%. A flexible piezoelectric nanogenerator prototype is demonstrated on the human finger and wrist, which opens up new avenues for the development of wearable electronic devices and provides valuable insights for further exploration in this field.

Abstract To achieve high power conversion efficiency in perovskite/silicon tandem solar cells, it is necessary to develop a promising wide-bandgap perovskite absorber and processing techniques in relevance. To date, the performance of devices based on wide-bandgap perovskite is still limited mainly by carrier recombination at their electron extraction interface. Here, we demonstrate assembling a binary two-dimensional perovskite by both alternating-cation-interlayer phase and Ruddlesden−Popper phase to passivate perovskite/C60 interface. The binary two-dimensional strategy takes effects not only at the interface but also in the bulk, which enables efficient charge transport in a wide-bandgap perovskite solar cell with a stabilized efficiency of 20.79% (1 cm2). Based on this absorber, a monolithic perovskite/silicon tandem solar cell is fabricated with a steady-state efficiency of 30.65% assessed by a third party. Moreover, the tandem devices retain 96% of their initial efficiency after 527 h of operation under full spectral continuous illumination, and 98% after 1000 h of damp-heat testing (85 °C with 85% relative humidity).

Abstract Advances in flexible electronics are driving the development of ferroelectric thin‐film capacitors toward flexibility and high energy storage performance. In the present work, the synergistic combination of mechanical bending and defect dipole engineering is demonstrated to significantly enhance the energy storage performance of freestanding ferroelectric thin films, achieved through the generation of a narrower and right‐shifted polarization‐electric field hysteresis loop. The recoverable energy storage density of freestanding PbZr0.52Ti0.48O3 thin films increases from 99.7 J cm−3 in the strain (defect) ‐free state to 349.6 J cm−3, marking a significant increase of 251%. The collective impact of the flexoelectric field, bending tensile strain, and defect dipoles contributes to this enhancement. The demonstrated synergistic optimization strategy has potential applicability to flexible ferroelectric thin film systems. Moreover, the energy storage properties of flexible ferroelectric thin films can be further fine‐tuned by adjusting bending angles and defect dipole concentrations, offering a versatile platform for control and performance optimization.

Abstract Solomon rings, upholding the symbol of wisdom with profound historical roots, were widely used as decorations in ancient architecture and clothing. However, it was only recently discovered that such topological structures can be formed by self-organization in biological/chemical molecules, liquid crystals, etc. Here, we report the observation of polar Solomon rings in a ferroelectric nanocrystal, which consist of two intertwined vortices and are mathematically equivalent to a $${4}_{1}^{2}$$ 4 1 2 link in topology. By combining piezoresponse force microscopy observations and phase-field simulations, we demonstrate the reversible switching between polar Solomon rings and vertex textures by an electric field. The two types of topological polar textures exhibit distinct absorption of terahertz infrared waves, which can be exploited in infrared displays with a nanoscale resolution. Our study establishes, both experimentally and computationally, the existence and electrical manipulation of polar Solomon rings, a new form of topological polar structures that may provide a simple way for fast, robust, and high-resolution optoelectronic devices.

Abstract The long‐term stability issue of halide perovskite solar cells hinders their commercialization. The residual stress–strain affects device stability, which is derived from the mismatched thermophysical and mechanical properties between adjacent layers. In this work, we introduced the Rb2CO3 layer at the interface of SnO2/perovskite with the hierarchy morphology of snowflake‐like microislands and dendritic nanostructures. With a suitable thermal expansion coefficient, the Rb2CO3 layer benefits the interfacial stress relaxation and results in a compressive stress–strain in the perovskite layer. Moreover, reduced nonradiative recombination losses and optimized band alignment were achieved. An enhancement of open‐circuit voltage from 1.087 to 1.153 V in the resultant device was witnessed, which led to power conversion efficiency (PCE) of 22.7% (active area of 0.08313 cm2) and 20.6% (1 cm2). Moreover, these devices retained 95% of its initial PCE under the maximum power point tracking (MPPT) after 2700 h. It suggests inorganic materials with high thermal expansion coefficients and specific nanostructures are promising candidates to optimize interfacial mechanics, which improves the operational stability of perovskite cells.

Motivated by advances in spintronic devices, extensive explorations are underway to uncover materials that host topologically protected spin textures, exemplified by skyrmions. One critical challenge involved in the potential application of skyrmions in van der Waals (vdW) materials is the attainment and manipulation of skyrmions at room temperature. In this study, we report the creation of an intrinsic skyrmion state in the van der Waals ferromagnet Fe3GaTe2. By employing variable temperature magnetic force microscopy, the skyrmion lattice can be locally manipulated on Fe3GaTe2 flakes. The ordering of skyrmion state is further analyzed. Our results suggest Fe3GaTe2 emerges as a highly promising contender for the realization of skyrmion-based layered spintronic memory devices.

Abstract Wrinkled ferroelectric polymer films with out‐of‐plane deformation exhibit exotic strain fields that differ from those of conventional epitaxial film systems, offering a new path toward manipulating electrical and mechanical behaviors in ferroelectrics. However, the direct observation of the domain structure evolution in ferroelectric polymer films during continuous deformation is challenging with current experimental approaches. In this study, the strain‐induced evolution of toroidal domain structures in organic poly(vinylidene fluoride‐ran‐trifluoroethylene) (P(VDF‐TrFE)) films with concentric toroidal wrinkle patterns is comprehensively investigated using phase‐field simulations. The results reveal morphology‐ and thickness‐dependent toroidal polar topology in wrinkled P(VDF‐TrFE) films. External strain loading can modulate this ferroelectric domain, which exhibits robust coupling behavior with a mixed strain field of periodic tensile and compressive strains. It is demonstrated that toroidal wrinkled ferroelectric films provide an effective and unique flexible platform for continuously controllable strain engineering in ferroelectrics and a theoretical framework with potential applications in flexible electronic devices.

Manipulating electrical and magnetic anisotropies will stimulate multi-terminal device applications. Here, the authors discover axis dependence of current rectifications, magnetic properties and magnon modes in van der Waals multiferroic CuCrP2S6.

Objective To evaluate the efficacy and safety of human coagulation factor Ⅷ developed by Shenzhen Weiguang Biological products Co, Ltd in the treatment of patients with hemophilia A. Methods A prospective, multi-center, open, single-group clinical study was conducted. A total of 65 subjects with hemophilia A were enrolled, and human coagulation factor Ⅷ(FⅧ) was injected according to the patients’ bleeding severity. The improvement score of bleeding symptoms and signs after the first infusion of the first bleeding event and the transfusion efficiency of FⅧ activity at 10 min and 1 hour after infusion were taken as the main efficacy indexes. The improvement scores of bleeding symptoms and signs after the first infusion and the increase of FⅧ activity at 10 min and 1 hour after infusion were the secondary efficacy indexes. Results The 65 subjects were enrolled in safety analysis set (SS) and full analysis set (FAS), and 58 of them were enrolled in protocol analysis set (PPS). Ten minutes and one hour after the first infusion, the level of factor Ⅷ activity in the subjects increased significantly, and the FⅧ activity increased by 100% or more in more than 79% of the subjects. The average infusion efficiency of FⅧ activity in all subjects was more than 100%. In 70% of the subjects, the pain was relieved rapidly and /or the bleeding symptoms were significantly improved 8 hours after each bleeding infusion, and the improvement rate of bleeding symptoms and signs reached 100% 72 hours after infusion. Conclusion After infusion of human coagulation factor Ⅷ, the activity level of factor Ⅷ in patients with hemophilia A significantly increased. The infusion efficiency can reach a optimal level, and the bleeding symptoms can be significantly improved.

Interfacial ferroelectricity may emerge in moiré superlattices. Here, the authors find that the polarized charge is much larger than the capacity of the moiré miniband and the associated anomalous screening exists outside the band.

Objective To evaluate the clinical efficacy and safety of one kind of human prothrombin complex concentrate in treatment of patients with hemophilia B. Methods The clinical data of 36 patients with hemophilia B treated with human prothrombin complex concentrate produced by Shenzhen Weiguang Biological Products Co. Ltd. from May 2018 to April 2019 were retrospectively analyzed, and its clinical efficacy and safety were analyzed. Results A total of 35 subjects entered the full analysis set (FAS)and safety set (SS), 33 subjects entered the per protocol Set (PPS). Thirty minutes after the first infusion of FAS subjects, the activity of coagulation factor Ⅸ increased from (3.93±0.975) IU/dL to (25.61±9.337) IU/dL, and the infusion efficiency was (96.43±22.007)%. The increased value of coagulation factor Ⅱ activity was (73.25±14.874) IU/dL. The activity of coagulation factor Ⅶ was (42.79±16.847) IU/dL. The increased value of coagulation factor Ⅹ activity was (65.29±17.042) IU/dL. The increased value of coagulation factor Ⅸ activity was (21.68±9.434%) IU/dL. Twenty-four hours after the first infusion of FAS subjects, the improvement of bleeding symptoms and signs was excellent in 21 cases (60%), improved in 14 cases (40.0%), and the effective rate was 100%. The incidence of adverse reactions was 2.9%(1/35), and there was no antibody to human coagulation factor Ⅸ and new virus infection. Conclusion Infusion of human prothrombin complex concentrate produced by Shenzhen Weiguang Biological Products Co. Ltd. in the treatment of hemophilia B has significant clinical efficacy and good safety.

Summary: How pathogens manipulate host UPRER to mediate immune evasion is largely unknown. Here, we identify the host zinc finger protein ZPR1 as an interacting partner of the enteropathogenic E. coli (EPEC) effector NleE using proximity-enabled protein crosslinking. We show that ZPR1 assembles via liquid-liquid phase separation (LLPS) in vitro and regulates CHOP-mediated UPRER at the transcriptional level. Interestingly, in vitro studies show that the ZPR1 binding ability with K63-ubiquitin chains, which promotes LLPS of ZPR1, is disrupted by NleE. Further analyses indicate that EPEC restricts host UPRER pathways at the transcription level in a NleE-ZPR1 cascade-dependent manner. Together, our study reveals the mechanism by which EPEC interferes with CHOP-UPRER via regulating ZPR1 to help pathogens escape host defense.

Driven by the minimization of total energy, the multi-domain morphology is preferred in as-grown ferroelectrics to reduce the depolarization and strain energy during the paraelectric to ferroelectric phase transition. However, the complicated multi-domain is not desirable for certain high-performance ferroelectric electro-optic devices. In this work, we achieve a reproducible and stable large-area monodomain in as-grown bulk ferroelectric single crystal [Formula: see text]. The monodomain dominates the entire single crystal, which is attributed to the internal charge carriers from the photoexcited disproportionation reaction of Sn ions. The charge carriers effectively screen the depolarization field and therefore decrease the depolarization energy and facilitate the formation of monodomain. This work offers a potential approach for engineering bulk ferroelectrics with a stable monodomain, which is desirable for the high-performance ferroelectric electro-optic devices.

Membrane-anchored PD-L1 homodimerizes in cells. N-glycosylation of PD-L1 regulates its homodimerization. The formation of PD-L1 homodimers further regulates their glycan processing, localization to the plasma membrane, and binding to PD-1.

Freestanding perovskite oxides pave the way to novel flexural properties. Here, the authors observe the nanoscale strain gradient induced flexoelectric polarization with an unusual flexo-expansion/shrinkage effect in freestanding ferroelectric oxide.

Abstract The ferroelectric chiral vortex domains are highly desirable for the application of data storage devices with low-energy consumption and high-density integration. However, the controllable switching of vortex chirality remains a challenge in the current ferroelectric community. Utilizing phase-field simulations, we investigate the vortex domain evolution and chirality formation in BiFeO3 thin films. By applying local surface charge or electric field, we demonstrate that the vorticity and the polarity can be manipulated by the initial bi-domain arrangement and the external field with different directions, respectively. By exchanging the domain arrangements, the opposite chirality can be obtained. Importantly, the topological vortex domain is retained after removing the external field. The vortex chirality can be switched reversibly with high reproducibility, which is beneficial to fatigue tolerance of the material in the operation. These results provide theoretical guidance for manipulating the vortex chirality in ferroelectric films.

Developing a single-phase self-rectifying memristor is desirable and functionally adaptive to dynamic environmental stimuli variations. Here, the authors report a single phase CuInP2S6 based memristor with continuously tunable current rectifying.

qRT-PCR is a common and key technical means to study gene expression in biological research. However, reliability and accuracy of quantification by qRT-PCR is entirely dependent on the identification of appropriate reference genes. Cucumber as an economical vegetable is widely cultivated worldwide and is subject to serious nematode infection, especially from M. incognita. Plant could employ beneficial soil bacteria in the rhizosphere to enhance plant adaptability to various stresses. In this study, the optimal reference genes in cucumber under M. incognita stress and Pseudomonas treatment were calculated and confirmed. A total of thirteen candidate reference genes were identified across three different treatments. Of these, geNorm, NormFinder and BestKeeper programs combined RefFinder software identified EF1 and UBI are the most suitable reference gene in the root knot and whole root of cucumber infected M. incognita, respectively, and CACS is the most suitable reference gene in the whole root of cucumber treated by Pseudomonas. The work first validated the most suitable reference genes for the normalization gene expression in cucumber by nematode infected or Pseudomonas inoculated, and these results would facilitate the further research on M. incognita or Pseudomonas soil rhizosphere microbe interaction with cucumber.

Summary: Background: Acute ischaemic stroke (AIS) is a highly heterogeneous disorder and warrants further investigation to stratify patients with different outcomes and treatment responses. Using a large-scale stroke registry cohort, we applied data-driven approach to identify novel phenotypes based on multiple biomarkers. Methods: In a nationwide, prospective, 201-hospital registry study taking place in China between August 01, 2015 and March 31, 2018, the patients with AIS who were over 18 years of age and admitted to the hospital within 7 days from symptom onset were included. 92 biomarkers were included in the analysis. In the derivation cohort (n=9539), an unsupervised Gaussian mixture model was applied to categorize patients into distinct phenotypes. A classifier was developed using the most important biomarkers and was applied to categorize patients into their corresponding phenotypes in an validation cohort (n=2496). The differences in biological features, clinical outcomes, and treatment response were compared across the phenotypes. Findings: We identified four phenotypes with distinct characteristics in 9288 patients with non-cardioembolic ischaemic stroke. Phenotype 1 was associated with abnormal glucose and lipid metabolism. Phenotype 2 was characterized by inflammation and abnormal renal function. Phenotype 3 had the least laboratory abnormalities and small infarct lesions. Phenotype 4 was characterized by disturbance in homocysteine metabolism. Findings were replicated in the validation cohort. In comparison with phenotype 3, the risk of stroke recurrence (adjusted hazard ratio [aHR] 2.02, 95% confidence intervals [CI] 1.04-3.94), and mortality (aHR 18.14, 95%CI 6.62-49.71) at 3-month post-stroke were highest in phenotype 2, followed by phenotype 4 and phenotype 1, after adjustment for age, gender, smoking, drinking, history of stroke, hypertension, diabetes mellitus, dyslipidemia, and coronary heart disease. The Monte Carlo simulation showed that the patients with phenotype 2 could benefit from high-intensity statin therapy. Interpretation: A data-driven approach could aid in the identification of patients at a higher risk of adverse clinical outcomes following non-cardioembolic ischaemic stroke. These phenotypes, based on different pathophysiology, can suggest individualized treatment plans. Funding: Beijing Natural Science Foundation (grant number Z200016), Beijing Municipal Committee of Science and Technology (grant number Z201100005620010), National Natural Science Foundation of China (grant number 82101360, 92046016, 82171270), Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences (grant number 2019-I2M-5-029).

Abstract Rational design of technologically important exotic perovskites is hampered by the insufficient geometrical descriptors and costly and extremely high-pressure synthesis, while the big-data driven compositional identification and precise prediction entangles full understanding of the possible polymorphs and complicated multidimensional calculations of the chemical and thermodynamic parameter space. Here we present a rapid systematic data-mining-driven approach to design exotic perovskites in a high-throughput and discovery speed of the A 2 BB’O6 family as exemplified in A 3TeO6. The magnetoelectric polar magnet Co3TeO6, which is theoretically recognized and experimentally realized at 5 GPa from the six possible polymorphs, undergoes two magnetic transitions at 24 and 58 K and exhibits helical spin structure accompanied by magnetoelastic and magnetoelectric coupling. We expect the applied approach will accelerate the systematic and rapid discovery of new exotic perovskites in a high-throughput manner and can be extended to arbitrary applications in other families.

Selenium-enriched mung bean (Se-MB) is a combination of mung bean (MB) and selenium (Se), which have a variety of potential biological activities. However, little is known about the skincare activity of Se-MB. The chemical composition of Se-MB fermentation broth (Se-MBFB) was analyzed to investigate the whitening, moisturizing, and anti-aging activities of Se-MBFB. The tyrosinase inhibition, anti-melanogenic in melanocytes (B16F10 cells), and moisturizing effect in human dermal fibroblasts (HDFs) were analyzed. Besides, the free radical scavenging activity of Se-MBFB was assessed in vitro. To verify the in vivo effects and the potential of practical applications of Se-MBFB, a clinical trial was conducted on the participants: 31 Chinese women aged 25–60 years, with no pigmentation disorder, no illness, no history of hypersensitivity reaction, and no use of skincare product on the face. The participants used an Se-MBFB masque for 15-20 min after cleaning the face. The measurement points were Week 0, 2, and 4 (W0, W2, and W4) after using the masque, and target sites were cheek and canthus. The following parameters were recorded on the target sites at each visit: melanin index, skin color, cuticle moisture content, transepidermal water loss, and crow's feet. The results demonstrated that Se-MBFB was rich in polyphenols, peptides, and γ-aminobutyric acid (GABA), displayed significant free radical scavenging and tyrosinase inhibiting activities, decreased the synthesis of melanin, and upregulated the aquaporin-3 (AQP3) expression. The test of the Se-MBFB mask showed that after 4 weeks of using the Se-MBFB facemask, the faces of the participants became whiter with reduced wrinkles and increased moisture content. Se-MB possessed the excellent whitening, moisturizing, and antioxidant efficacy, which could lay a scientific foundation for utilization and development of skincare products of Se-MB and its related industrial cosmetics products.

The wind field has a great influence on the control stability of Tilt-rotor unmanned aerial vehicle (UAV), especially during the take-off and landing phase. The airspeed of UAV is so small during these phases that it cannot generate stable aerodynamic forces, which will significantly reduce the wind robustness of Tilt-rotor UAV. In this article, the disturbance of wind field is analyzed from two perspectives: the wind field acting on the UAV fuselage, which is regarded as external interference, and the wind acting on the propeller, which is considered as modeling error. After analyzing the interference mechanism of wind field, a generalized extended state observer (GESO) and a H∞ robust control method with mixed sensitivity are proposed, which could empower the Tilt-rotor UAV with good interference suppression ability as well as better performance tracking ability. Finally, the laboratory simulation and flight experiment are studied. The results validate the theory and prove that the proposed method could resist the interference of wind field and shows excellent control effect.

In this paper, a control method of a novel tilt-rotor UAV with a blended wing body layout is studied. The novel UAV is capable of vertical take-off and landing and has strong stealth capabilities that can be applied to carrier-borne reconnaissance aircraft. However, the high aspect ratio of blended wing body UAVs leads to a wingtip or oar-tip touchdown problem when adopting the conventional position-attitude control (CPAC) scheme with a large crosswind disturbance. Moreover, when the UAV is subject to interference during reconnaissance, aerial photography, and landing missions, the conventional scheme cannot provide both attitude stability and track accuracy. First, a direct thrust vectoring control (DTVC) scheme is proposed. The control authority of the rotor tilt mechanism was added to enable the decoupling of the attitude and trajectory and to improve the response rate and response bandwidth of the flight trajectory. Second, considering the problems of strong couplings and parameter uncertainties and the nonlinear features and mismatched perturbations that are inevitable in the tilt-rotor, we designed a robust UAV controller based on the backstepping sliding mode control method and determined the stability of the control system through the Lyapunov function. Finally, in the case of crosswire interference during vertical takeoff and landing and the aerial photography missions of the UAV, the numerical simulation of the CPAC scheme and the DTVC scheme was carried out, respectively, and the Monte Carlo random test method was introduced to conduct the statistical test of the landing accuracy. The simulation results show that the DTVC scheme improves the landing accuracy and speed compared to the CAPC scheme and decouples the position control loop from the attitude control loop, finally enabling the UAV to complete the flight control in the VTOL phase.

Rotation modulation can significantly improve the navigation accuracies of an inertial navigation system (INS) and a strap-down configuration dominating in this type of INS. However, this style of construction is not a good scheme since it has no servo loop to counteract a vehicle manoeuvre. This paper proposes a rotary upgrading method for a rotational INS based on an inertially stabilized platform. The servo control loop is reconstructed on a four-gimbal platform, and it has the functions of providing both a level stability relative to the navigation frame and an azimuth rotation at a speed of 1:2◦/s. With the platform’s rotation, the observability and the convergence speed of the estimation for the initial alignment can be improved, as well as the biases of the gyroscopes and accelerometers be modulated into zero-mean periodic values. An open-loop initial alignment method is designed, and its detailed algorithms are delivered. The experiment result shows that the newly designed rotational INS has reached an accuracy of 0.38 n mile/h (CEP, circular error probable). The feasibility and engineering applicability of the designed scheme have been validated.

The optimal trajectory planning for a novel tilt-rotor unmanned aerial vehicle (UAV) in different take-off schemes was studied. A novel tilt-rotor UAV that possesses characteristics of both tilt-rotors and a blended wing body is introduced. The aerodynamic modeling of the rotor based on blade element momentum theory (BEMT) is established. An analytical method for determining the taking-off envelope of tilt angle versus airspeed is presented. A novel takeoff–tilting scheme, namely tilting take-off (TTO), is developed, and its optimal trajectory is designed based on the direct collocation method. Parameters such as the rotor thrust, tilt angle of rotor and angle of attack are chosen as control variables, and the forward velocity, vertical velocity and altitude are selected as state variables. The time and the energy consumption are considered in the performance optimization indexes. The optimal trajectories of the TTO scheme and other conventional schemes including vertical take-off (VTO) and short take-off (STO) are compared and analyzed. Simulation results indicate that the TTO scheme consumes 47 percent less time and 75 percent less energy than the VTO scheme. Moreover, with minor differences in time and energy consumption compared to the STO scheme, but without the need for sliding distance, TTO is the optimal take-off scheme to satisfy the flight constraints of a novel tilt-rotor UAV.

Aiming to improve the positioning accuracy of an unmanned aerial vehicle (UAV) swarm under different scenarios, a two-case navigation scheme is proposed and simulated. First, when the Global Navigation Satellite System (GNSS) is available, the inertial navigation system (INS)/GNSS-integrated system based on the Kalman Filter (KF) plays a key role for each UAV in accurate navigation. Considering that Kalman filter’s process noise covariance matrix Q and observation noise covariance matrix R affect the navigation accuracy, this paper proposes a dynamic adaptive Kalman filter (DAKF) which introduces ensemble empirical mode decomposition (EEMD) to determine R and adjust Q adaptively, avoiding the degradation and divergence caused by an unknown or inaccurate noise model. Second, a network navigation algorithm (NNA) is employed when GNSS outages happen and the INS/GNSS-integrated system is not available. Distance information among all UAVs in the swarm is adopted to compensate the INS position errors. Finally, simulations are conducted to validate the effectiveness of the proposed method, results showing that DAKF improves the positioning accuracy of a single UAV by 30–50%, and NNA increases the positioning accuracy of a swarm by 93%.

The airspeed is an important feedback signal for flight control, and its measurement accuracy is related to the safety of aircraft, especially for hybrid vertical takeoff and landing (VTOL) unmanned aerial vehicles (UAV) in the transition phase. However, offline calibration of the pitot tube cannot fully simulate the situation in real cases, and this is why online calibration after installation is necessary. In addition, the environmental wind field creates a high risk for the conversion flight of a hybrid UAV, thus real-time wind field measurement of the flight field has great significance for the flight path planning of the conversion process. In this article, an innovative method for online calibration of pitot tube and wind field estimation is proposed. After establishing the extended Kalman filter (EKF) for estimation, an analysis method is proposed to analyze the observability of EKF under different flight strategies. Then, the hovering flight is selected as the experimental flight trajectory. The laboratory computer simulation and flight experiment results validate the theory and prove that the proposed method could re-calibrate the scale factor of the pitot tube and estimate the wind field.

A novel integrated guidance and control (IGC) scheme for a Re-entry Hypersonic Vehicle (RHV) is proposed with the capabilities of online aerodynamic coefficient estimation based on an Unscented Kalman Filter and online trajectory generation based on the Gaussian pseudospectral method. A linear quadratic regulator is adopted for trajectory tracking guidance and a second-layer sliding mode controller is designed for attitude control. The variation of lift and drag coefficients are modeled and estimated online, based on which a new trajectory can be generated. The commands of trajectory generation are set as moments of actuators and their extremums pose more constraints on the rate and acceleration of flow angles. Comprehensive simulations are conducted and comparable IGC performances with normal conditions are obtained under large aerodynamic coefficient errors according to online generated trajectory, which proves the effectiveness and advantages of the proposed IGC scheme.

Layered van der Waals interacting system that can be exfoliated to few layers are promising for exploring fundamental physics with rich electronic and optical properties. Combining the emerging phenomenon with long-range magnetic orders could lead to novel potential ultra-compact spintronics. Recently, CrXTe3 (X=Ge, Si) were reported that can persist magnetism after being exfoliated to few layers, however the magnetic domain structure in layered or bulk single crystal has remained unexplored. Here we choose CrSiTe3 single crystal as a model system, combining low-temperature magnetic force microscope, to demonstrate the magnetic domain structure, as well as the domain evolution in the presence of magnetic field, which is consistent with the magnetic behaviors measured by Magnetic Properties Measurement System (MPMS). Our result gives a simple portray of the magnetic properties of single crystal CrSiTe3, which provides a basis for the future research on magnetic layered van der Waals interacting system in potential application at 2-dimensional limit.

Alpha stable noise, determined by four parameters, has been found in the random error of a laser gyroscope. Accurate estimation of the four parameters is the key process for analyzing the properties of alpha stable noise. Three widely used estimation methods—quantile, empirical characteristic function (ECF) and logarithmic moment method—are analyzed in contrast with Monte Carlo simulation in this paper. The estimation accuracy and the application conditions of all methods, as well as the causes of poor estimation accuracy, are illustrated. Finally, the highest precision method, ECF, is applied to 27 groups of experimental data to estimate the parameters of alpha stable noise in a laser gyroscope’s random error. The cumulative probability density curve of the experimental data fitted by an alpha stable distribution is better than that by a Gaussian distribution, which verifies the existence of alpha stable noise in a laser gyroscope’s random error.

A comparison study for solving diffusion equations with different algorithm methods is studied to understand the oxygen vacancy defect transport under the electric field. We compare computational efficiency and numerical accuracy with different algorithm methods, including finite difference, finite element (COMSOL), and Fourier-Chebysev spectral methods. All the results of oxygen vacancy distribution under an electric field from different algorithm methods are compared with the analytical solution results. Two kinds of boundary conditions are used in solving diffusion equations and the absolute error of different methods are discussed. The main purpose of these results is to provide guidance for studying the role of point defect transport in the degradation and breakdown of devices.

We report the coexistence of ferroelectricity and a spin liquid state in hexagonal TbInO_{3} with quasi-two-dimensional triangular spin lattice. Geometrical ferroelectricity associated with In trimerization accompanies topological ferroelectric structural defects. Magnetic susceptibility data show in-plane magnetic anisotropy of Tb spins without any long-range order above 1.8 K, and we also confirm no trace of any phase transition down to 0.15 K from a specific heat measurement, which indicates that this system is highly frustrated and may host a spin liquid ground state. By analyzing the Schottky anomaly in the specific heat results, we propose a model where crystal-field levels are different in each Tb sites, and only one of them has a magnetic ground state and forms a unique honeycomb spin lattice. These observations put forward an interesting possibility where spin liquid and ferroelectric behaviors coexist, and the atomically sharp ferroelectric domain walls may host new magnetic edge states or local spin excitations.

Chirality, i.e., handedness, pervades much of modern science from elementary particles, DNA-based biology to molecular chemistry; however, most of the chirality-relevant materials have been based on complex molecules. Here, we report inorganic single-crystalline Ni3TeO6, forming in a corundum-related R3 structure with both chirality and polarity. These chiral Ni3TeO6 single crystals exhibit a large optical specific rotation (α)—1355° dm−1 cm3 g−1. We demonstrate, for the first time, that in Ni3TeO6, chiral and polar domains form an intriguing domain pattern, resembling a radiation warning sign, which stems from interlocked chiral and polar domain walls through lowering of the wall energy.

Topological vortices with complex domains and domain walls exist in hexagonal manganites, which undergo a structural transition accompanying ferroelectric polarization and trimerization. We have systematically studied the origin of two different types (type-I and type-II) of vortex domains with controlled oxygen stoichiometry and found that the evolution between type-I and type-II vortex domains and the presence of charged walls between two different trimerization antiphase domains result from an oxygen vacancy gradient. We have also discovered a rare phenomenon of vortex core split, which appears to stem from the instability of charged ferroelectric walls between domains with the same trimerization antiphase.

Ultratightly coupled (UTC) architecture is believed to be the best architecture for Global Positioning System (GPS) and Inertial Navigation System (INS) integration system due to the advanced data fusion strategy and effective mutual assistance between the subsystems. However the performance of UTC GPS/INS system will be degraded by severe jamming interference, especially when low-grade inertial measurement unit (IMU) is used. To solve this problem an innovative architecture of UTC GPS/INS system is proposed. Since GPS receiver’s antijamming ability is closely related to tracking loop bandwidth, adaptive tracking loop bandwidth based on the fuzzy logics is proposed to enhance antijamming ability for GPS receiver. The bandwidth will be adapted through a fuzzy logic controller according to the calculated carrier to noise intensity ratio (C/N0). Moreover, fuzzy adaptive integration Kalman filter (IKF) is developed to improve estimation accuracy of IKF when measurement noises change. A simulation platform is established to evaluate the innovative architecture and results demonstrate that the proposed scheme improves navigation performance significantly under severe jamming conditions.

Hand, foot and mouth disease (HFMD), mainly caused by enterovirus 71 (EV71), has frequently occurred in the Asia-Pacific region, posing a significant threat to the health of infants and young children. Therefore, research on the infection mechanism and pathogenicity of enteroviruses is increasingly becoming important. The 3D polymerase, as the most critical RNA-dependent RNA polymerase (RdRp) for EV71 replication, is widely targeted to inhibit EV71 infection. In this study, we identified a novel host protein, AIMP2, capable of binding to 3D polymerase and inhibiting EV71 infection. Subsequent investigations revealed that AIMP2 recruits the E3 ligase SMURF2, which mediates the polyubiquitination and degradation of 3D polymerase. Furthermore, the antiviral effect of AIMP2 extended to the CVA16 and CVB1 serotypes. Our research has uncovered the dynamic regulatory function of AIMP2 during EV71 infection, revealing a novel antiviral mechanism and providing new insights for the development of antienteroviral therapeutic strategies. [ABSTRACT FROM AUTHOR]

Influenza A virus (IAV) binds sialic acid receptors on the cell surface to enter the host cells, which is the key step in initiating infection, transmission and pathogenesis. Understanding the factors that contribute to the highly efficient entry of IAV into human cells will help elucidate the mechanism of viral entry and pathogenicity, and provide new targets for intervention. In the present study, we reported a novel membrane protein, C1QTNF5, which binds to the hemagglutinin protein of IAV and promotes IAV infection in vitro and in vivo. We found that the HA1 region of IAV hemagglutinin is critical for the interaction with C1QTNF5 protein, and C1QTNF5 interacts with hemagglutinin mainly through its N-terminus (1-103 aa). In addition, we further demonstrated that overexpression of C1QTNF5 promotes IAV entry, while blocking the interaction between C1QTNF5 and IAV hemagglutinin greatly inhibits viral entry. However, C1QTNF5 does not function as a receptor to mediate IAV infection in sialic acid-deficient CHO-Lec2 cells, but promotes IAV to attach to these cells, suggesting that C1QTNF5 is an important attachment factor for IAV. This work reveals C1QTNF5 as a novel IAV attachment factor and provides a new perspective for antiviral strategies. [ABSTRACT FROM AUTHOR]