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We report the most sensitive upper limits to date on the 21 cm epoch of reionization power spectrum using 94 nights of observing with Phase I of the Hydrogen Epoch of Reionization Array (HERA). Using similar analysis techniques as in previously reported limits, we find at 95% confidence that Δ2(k = 0.34 h Mpc−1) ≤ 457 mK2 at z = 7.9 and that Δ2(k = 0.36 h Mpc−1) ≤ 3496 mK2 at z = 10.4, an improvement by a factor of 2.1 and 2.6, respectively. These limits are mostly consistent with thermal noise over a wide range of k after our data quality cuts, despite performing a relatively conservative analysis designed to minimize signal loss. Our results are validated with both statistical tests on the data and end-to-end pipeline simulations. We also report updated constraints on the astrophysics of reionization and the cosmic dawn. Using multiple independent modeling and inference techniques previously employed by HERA Collaboration, we find that the intergalactic medium must have been heated above the adiabatic cooling limit at least as early as z = 10.4, ruling out a broad set of so-called “cold reionization” scenarios. If this heating is due to high-mass X-ray binaries during the cosmic dawn, as is generally believed, our result’s 99% credible interval excludes the local relationship between soft X-ray luminosity and star formation and thus requires heating driven by evolved low-metallicity stars.

The partial space elevator (PSE) is a space transportation system that consists of one main satellite and one end body connected to a piece of tether. A climber can move along the tether conveying the cargo. This chapter studies a new configure-keeping technology for the stable cargo transportation of the PSE. The new technology contains two control modules. Module I predicts the optimal climber speed as a reference and suppresses the libration motions using the actuators on the climber. The control law of Module I is designed based on an analytical climber speed function, PPC control is used to compensate for system error. Module II further stabilizes the system by eliminating the possible disturbances in real-time acting on the end body. Two control modes are used given to further ensure the system configuration keeping. To test the validity of the proposed technology, two cases are simulated. The numerical results show that the proposed configuration keeping technology is very effective in dealing with the configuration keeping problems for the partial space elevators and other complex nonlinear dynamic systems in the aerospace engineering area.

The partial space elevator is a space transportation system that conveys cargo by a climber moving along the tether that connects the main satellite and the end body. This work proposed a novel prescribed performance based dual-loop control strategy for configuration keeping of the partial space elevator in cargo transportation. The control loop I controls the libration angle of the climber by a newly proposed prescribed performance control law to track the desired state with bounded performance. The Lyapunov stability of the control law is proved analytically. Control loop II stabilizes the overall configuration of the PSE by applying thrust and deploying/retrieving the tether simultaneously at the end body. To enforce the constraint that the total tether length is unchanged at the end of transportation, an event-triggered loaning control algorithm is proposed to further improve the Control loop II. Numerical simulations validate the prescribed performance based dual-loop control strategy. The results show that the stable configuration of the PSE is kept effectively with no libration motion in the period of cargo transportation.

Spacecraft formation maneuvering will inevitably induce flexible vibration from flexible appendages of spacecraft such as solar array appendages or antennae, which leads to complex disturbances with unknown fundamental frequencies. To achieve high performance of spacecraft formation flying, a novel adaptive iterative learning disturbance observer based on adaptive notch filter is designed to estimate and compensate unknown multi-frequency disturbances. Different from existing results on iterative learning disturbance observer, the newly proposed observer can estimate effectively both low-frequency disturbances and high-frequency periodic disturbances. Based on the proposed observer, an output feedback pose tracking law is derived by combining the proposed velocity observer and a feedback controller in dual quaternions description. The stability of the closed-loop system is approved based on the Lyapunov framework. Finally, the effectiveness and accuracy of the proposed observer and controller are demonstrated successfully by numerical simulations.

A novel concept of a looped tether transportation system with multiple rungs (L-TTS-R) is proposed for highly efficient payload transfer in space. In addition to two huge platforms connected by two parallel tethers with multiple moving climbers, some rigid rungs are evenly distributed between the two tethers in L-TTS-R to suppress the libration movement of the system and to reduce or avoid the risk of collision between climbers and tethers in the process of payload transportation. To establish an accurate model of L-TTS-R in the framework of multibody system dynamics, the gradient deficient beam elements of the absolute nodal coordinate formulation (ANCF) are used to mesh two tethers. The sliding joint based on ANCF is introduced to build up the contact interaction model between tethers and climbers. The generalized forces acting on the L-TTS-R, for example, the gravitational force and the elastic force, are derived in brief. The generalized-alpha method is used to solve the dynamics equations of the constrained flexible multibody systems. Some representative examples are given to validate the effectiveness of the proposed L-TTS-R model for space payload transfer missions and to assess the influence of rungs on the system libration suppression, the climber collision risk avoidance, the relative oscillation and pitching motion of platforms, and the tether tensions. The numerical results reveal that the L-TTS-R shows distinct effects on suppressing the overall libration of the system, reducing or even avoiding the risk of collision between climbers and tethers and decreasing significantly the oscillating magnitudes of the relative distances between two platforms, and these effects are more visible with increasing the number of rungs.

This paper describes the experimental validation of a CubeSat tether deployment design by air-bearing ground test and microgravity parabolic flight test. The tethered CubeSat mission includes two 1U CubeSats with a tape-type tether of 100 m. The tether will be deployed by pull with two CubeSats separating at a desired velocity. Various ground tests were performed to validate the designed separation velocity, estimate the internal friction force, and measure the deployed tether length. Finally, the engineering model of tether deployment system is validated by microgravity parabolic flight testing. The parabolic flight demonstrated the tether deployment system works as expected. By measuring the separation velocity of CubeSats in the parabolic flight, it reveals the internal friction is much less in the microgravity environment than the value measured on the ground.

Attitude stabilization of a massive rotating uncooperative target by a tethered space tug is studied for orbit maneuvering in the postcapture operation analytically and experimentally. The perturbed orbital propagation of the tethered space system is described with nonsingular orbital elements and the relative equations of motion of the tethered space system, including the tether libration and attitudes of target and tug, are established in the orbital frame. The tether tension control, the tug's attitude control, and the combination control of them are designed to suppress the attitude and libration motions of the target/tug and the tethered space system with bounded stability. The control law's effectiveness is demonstrated by simulation and then validated experimentally by a microgravity testbed with two tethered free-floating air-bearing satellite simulators.

Supplemental Digital Content is available in the text., Background and Purpose: Chronic kidney disease with reduced estimated glomerular filtration rate or elevated albuminuria increases risk for ischemic and hemorrhagic stroke. This study assessed the effects of sodium glucose cotransporter 2 inhibitors (SGLT2i) on stroke and atrial fibrillation/flutter (AF/AFL) from CREDENCE (Canagliflozin and Renal Events in Diabetes With Established Nephropathy Clinical Evaluation) and a meta-analysis of large cardiovascular outcome trials (CVOTs) of SGLT2i in type 2 diabetes mellitus. Methods: CREDENCE randomized 4401 participants with type 2 diabetes mellitus and chronic kidney disease to canagliflozin or placebo. Post hoc, we estimated effects on fatal or nonfatal stroke, stroke subtypes, and intermediate markers of stroke risk including AF/AFL. Stroke and AF/AFL data from 3 other completed large CVOTs and CREDENCE were pooled using random-effects meta-analysis. Results: In CREDENCE, 142 participants experienced a stroke during follow-up (10.9/1000 patient-years with canagliflozin, 14.2/1000 patient-years with placebo; hazard ratio [HR], 0.77 [95% CI, 0.55–1.08]). Effects by stroke subtypes were: ischemic (HR, 0.88 [95% CI, 0.61–1.28]; n=111), hemorrhagic (HR, 0.50 [95% CI, 0.19–1.32]; n=18), and undetermined (HR, 0.54 [95% CI, 0.20–1.46]; n=17). There was no clear effect on AF/AFL (HR, 0.76 [95% CI, 0.53–1.10]; n=115). The overall effects in the 4 CVOTs combined were: total stroke (HRpooled, 0.96 [95% CI, 0.82–1.12]), ischemic stroke (HRpooled, 1.01 [95% CI, 0.89–1.14]), hemorrhagic stroke (HRpooled, 0.50 [95% CI, 0.30–0.83]), undetermined stroke (HRpooled, 0.86 [95% CI, 0.49–1.51]), and AF/AFL (HRpooled, 0.81 [95% CI, 0.71–0.93]). There was evidence that SGLT2i effects on total stroke varied by baseline estimated glomerular filtration rate (P=0.01), with protection in the lowest estimated glomerular filtration rate (

This paper investigates the tracking and control problem of a spacecraft rendezvous with a non-cooperative and tumbling space target subject to parametric uncertainty and unknown external disturbances. The kinematics and dynamics of spacecraft position and attitude are described by dual quaternions. A novel adaptive sliding mode disturbance observer is proposed to track the pose of non-cooperative tumbling target without need for upper bounds of first and second derivatives of lumped disturbance. Based on the proposed observer, a finite time sliding mode control is developed in term of dual quaternion. Different from existing sliding mode control schemes, the conditions on the controller parameters bounds are relaxed. The stability and robustness of the overall closed-loop control is proved by the Lyapunov framework. The robustness and effectiveness of the proposed control scheme are validated by numerical simulations in comparison with existing approaches.

This paper explores a new control strategy to suppress the libration of a partial space elevator by applying torque control at the climber only. The control torque at the climber is generated by reaction wheels. A new dynamic model of the partial space elevator is developed by integrating the attitude dynamics of the climber into the classical two-piece dumbbell model. The influence of the climber attitude motion on the libration motion of the partial space elevator is analyzed with and without the control torque at the climber. Based on the characteristics of the system dynamics, a novel reaction wheel control strategy is proposed to suppress both the libration of the elevator and the climber attitude motion. Such a new control strategy is implemented by an optimal control scheme. The simulation results validate the effectiveness of the proposed control strategy, which provides a new alternative method to stabilize the libration of the partial space elevator for fast transfer of cargo with constant speeds. To avoid the adverse effect on the reaction wheel due to the frequent switch of rotation direction, a control strategy by two unidirectional reaction wheels is proposed to achieve the same control effect, where the reaction wheels rotate in only one direction.

This paper proposes a novel finite element Kalman filter to estimate the unmeasurable state of space tether systems based on the measured state at its ends only. The finite element method calculates the unmeasurable internal state as the virtual measurement based on the dynamic model of the system by imposing the input of measured state at the boundary to the model using the Lagrange multiplier method in the spatial space. Combining the real and virtual measurement into a hybrid measurement model of the system, the full state is reconstructed and propagated in the temporal space by the extended Kalman filter. Two state-space system models, the dynamics-based and kinematics-based state models, in the Kalman filter are explored. The observability and stability of the newly proposed finite element Kalman filter are examined and proved. The advantages of the proposed state estimator are (i) the singularity in the virtual measurement of state caused by the number of internal state greater than the number of state measured at the boundary is eliminated in the statistic meaning by the Kalman filter, and (ii) the effects of noises of the observation data and the uncertainties of model discretization are considered and minimized. The correctness and effectiveness of the proposed state estimator is demonstrated by the numerical analysis of a space tether system orbiting around the Earth. The results show the proposed state estimator with only measured state at the ends of the tether successfully provides an accurate time history estimation of geometric configuration and motion of the entire tether. Moreover, the results also show the difference caused by the dynamics-based and kinematics-based system models in the state estimator is negligible. The kinematics-based system model should be used in the state estimator due to its significantly low computational load. Finally, the proposed method can be easily applied for the state estimation process for other space tethered spacecraft systems.

Data-driven single image deraining (SID) models have achieved greater progress by simulations, but there is still a large gap between current deraining performance and practical high-level applications, since high-level semantic information is usually neglected in current studies. Although few studies jointly considered high-level tasks (e.g., segmentation) to enable the model to learn more high-level information, there are two obvious shortcomings. First, they require the segmentation labels for training, limiting their operations on other datasets without high-level labels. Second, high- and low-level information are not fully interacted, hence having limited improvement in both deraining and segmentation tasks. In this paper, we propose a Semantic Guided Interactive Network (SGINet), which considers the sufficient interaction between SID and semantic segmentation using a three-stage deraining manner, i.e., coarse deraining, semantic information extraction, and semantics guided deraining. Specifically, a Full Resolution Module (FRM) without down-/up-sampling is proposed to predict the coarse deraining images without context damage. Then, a Segmentation Extracting Module (SEM) is designed to extract accurate semantic information. We also develop a novel contrastive semantic discovery (CSD) loss, which can instruct the process of semantic segmentation without real semantic segmentation labels. Finally, a triple-direction U-net-based Semantic Interaction Module (SIM) takes advantage of the coarse deraining images and semantic information for fully interacting low-level with high-level tasks. Extensive simulations on the newly-constructed complex datasets Cityscapes_syn and Cityscapes_real demonstrated that our model could obtain more promising results. Overall, our SGINet achieved SOTA deraining and segmentation performance in both simulation and real-scenario data, compared with other representative SID methods.

This paper proposes a novel concept of looped tether transportation system with multiple climbers for highly efficient transportation of payloads. It is formed by connecting two parallel tether transportation systems or partial space elevators with multiple climbers per tether at upper and lower ends. A high-fidelity and accurate model for the system is built up to capture the high order flexural modes of tethers based on the nodal position finite element method in the arbitrary Lagrangian-Eulerian description. Numerical analysis is conducted to understand the dynamic characteristics of the looped tether transportation system compared to the tether transportation system with a single tether. The results show that the high-order flexural modes of tethers must be considered in the system's engineering analysis. The analysis also shows the interaction between two tethers caused by climbers on different tethers moving in different directions could be beneficial. It will reduce the overall libration of the system while keeping the magnitude of tether tension comparable to the tether transportation system with a single tether. In addition, the analysis of high order flexural modes of tether indicates that there exists a risk of tether collision in the payload transportation, which indicates again the necessity to include the high order flexural modes of tether in the analysis. Finally, the study shows the risk of tether collision could be avoided by optimizing the number of climbers per tether, the climber's moving profiles, and the distance between climbers using the optimal control methodology.

The paper studies the stability and control of radial deployment of an electric solar wind sail with the consideration of high-order modes of elastic tethers. The electric solar wind sail is modeled by combining the flexible tether dynamics, the rigid-body dynamics of central spacecraft, and the flexible-rigid kinematic coupling. The tether deployment process is modeled by the nodal position finite element method in the arbitrary Lagrangian–Eulerian framework. A symplectic-type implicit Runge–Kutta integration is proposed to solve the resulting differential–algebraic equation. A proportional–derivative control strategy is applied to stabilize the central spacecraft’s attitudes to ensure tethers’ stable deployment with a constant spinning rate. The results show the electric solar wind sail requires thrust at remote units in the tangential direction to counterbalance the Coriolis forces acting on the tethers and remote units to deploy tethers radially successfully. The parametric analysis shows the tether deployment speed and the thrust magnitude significantly impacts deployment stability and tether libration, which opens the possibility of successful deployment of tethers by using optimal control. Finally, the analysis results show that radial deployment is advantageous due to the isolated deployment mechanism, and a jammed tether can be isolated from affecting the deployment of rest tethers.

This paper investigates the dynamic characteristics of thrust-induced sail plane coning and attitude motion of an electric solar wind sail (E-sail) by considering high-order modes of flexible elastic tethers. The tethers of the E-sail are assumed elastic and discretized into inter-connected 2-noded tensile elements using the nodal position finite element method, while the central spacecraft and the remote units are simplified as lumped masses. The E-sail is assumed in the heliocentric ecliptic orbital plane at a distance of 1 au from the Sun. The influences of the propulsive force models and the initial E-sail orientation on the dynamic characteristics of the sail plane coning and attitude motion of E-sail are analyzed. The current work derives an analytic expression of the coning motion frequency under the assumption of small coning angle. Through parametric analyses, the current work shows that the magnitude of the propulsive force significantly influences the increment magnitude of the E-sail's orbital radius while has little effect on the angles of sail and thrust angles and the E-sail spin rate. The parametric analyses also show that the initial E-sail orientation significantly influences the thrust vector and the variation of sail angle. Finally, the relationships of the sail and thrust angles, as well as the dimensionless acceleration of the E-sail, are given in polynomial expressions by curve-fitting of simulation results of E-sails with the consideration of coning motion. The relationships are compared with the previous results of E-sails without including coning motion. It shows the coning motion has negligible effect on the macro dynamic behaviors of E-sail.

This paper studies the consensus tracking control for a class of uncertain high-order nonlinear multi-agent systems under an undirected leader-following architecture. A novel distributed finite-time adaptive control framework is proposed based on the barrier function. The distributed cascaded high-gain observers are introduced to solve the problem of robust consensus tracking with unmeasured intermediate states in multi-agent systems based on the proposed control framework. The proposed control schemes guarantee the finite-time consensus of multi-agent systems, which is proven by the finite-time Lyapunov stability and singular perturbation theory. In conclusion, numerical simulations verify the proposed control protocols’ effectiveness, and their performance advantages are shown by comparing them with another existing method.

Adsorption on mineral surfaces is a crucial process controlling (bio)geochemical cycling of Cd, and Cd isotopic behaviour during adsorption is an important but little investigated aspect of Cd isotope systematics. This work looked at the fractionation of Cd isotopes during Cd adsorption onto calcite, which is an important sink of Cd but isotopic behaviour has only previously been investigated in co-precipitation experiments. The Cd isotope composition of calcite adsorbed components was determined to be lighter and consistent with equilibrium fractionation in all experiments. And degree of fractionation observed in our experiments is not influenced by the Cd/CaCO3 ratio, pH value or Cd/PO43− ratio in the studied range. In MQ water, the observed fractionation value αsorbed-aqueous is 0.99934 but this α value is affected by the presence of other compounds. Notably, αsorbed-aqueous = 0.99984, a reduced but resolvably lower value fractionation, was observed in the presence of PO43− which may be an important factor to be considered when interpreting Cd isotope signatures in nature. The enrichment of lighter Cd isotopes may result from highly distorted octahedral Cdsingle bondO6 sites of inner-sphere Cd complexes on calcite, indicated by extended X-ray absorption fine structure (EXAFS). However, near identical coordination environments of the aqueous and sorbed Cd species in the presence of PO43− likely led to the reduced Cd isotope fractionation. This work suggests adsorption of Cd onto carbonates minerals may produce significant Cd isotope fractionation between fluids and solid phase. Our observations offer an alternative process apart from co-precipitation when interpreting Cd isotope ratios in the presence of calcite in paleo-geological studies and could be helpful to better understand Cd (bio)geochemical cycling.

This paper studies the libration suppression of a moon-based partial space elevator in the Earth-Moon three-body system. The elevator is connected to the Moon surface by a tether and a space station is connected to the free end of tether as the end body. One or multiple climber(s) can move along the tether to transfer cargos between the Moon and the end body. A high-fidelity dynamic model is derived to describe the motion of the climber(s), the end body and the flexible tether by the combination of rigid body dynamics and nodal position finite element method. The validity of the proposed model and the effect of element discretization along the tether on the dynamic behaviour of the elevator are investigated through numerical simulations. To ensure the stability and satisfy the mission constraints in the cargo transfer period, an optimal control based on the high-fidelity model is employed to regulate the control input with limited magnitude. Case studies show that by adjusting the thrusts on the end body reasonably, the libration of the Moon-based partial space elevator can be suppressed with limited control input effectively.

The number-of-constituent-quark (NCQ) scaling behavior of the elliptic flow of identified particles produced in A+A collisions is studied quantitatively using an empirical function that fits the experimental $v_2$ data available from the RHIC and LHC. The most common approach for NCQ scaling involves (1) doing a scaling of the experimental $v_2$ data of an identified particle with its NCQ, (2) doing the same to its transverse momentum or energy, then (3) combining all the scaled data and identifying the NCQ behavior by intuitively looking (since the measured experimental data are discrete). We define two variables $(d_1, d_2)$ to describe NCQ scaling quantitatively and simultaneously, and identify the approximate region where the NCQ scaling holds. This approach could be applied to study NCQ or other scaling phenomena in future experiments., Comment: 7 pages, 4 figures

This paper studies the libration-free cargo transfer control of a partial space elevator where the main satellite may change its orbital state in the transfer period. The orbital motion of the main satellite in the climber transfer period is first studied. Then, a reduced-order libration-free dynamics of the partial space elevator is derived. Accordingly, a novel libration-free switching control strategy is proposed to stabilize the cargo transportation with two alternating controllers. The Controller I controls the cargo speed in the libration-free mode by a shrinking horizon model predictive control based on the reduced-order libration-free dynamic mode of the partial space elevator. This leads to high computational efficiency in control. Once the libration is induced by the cargo transfer, the control turns off the Controller I and activates the Controller II to suppress the libration to zero within one time step of the Controller I by a novel prescribed-time control law based on the fixed-time control scheme. The stability of the control is proved in the Lyapunov framework. The validity and effectiveness of the proposed control strategy are demonstrated by computation simulation. Simulation results reveal that the proposed control strategy is effective in keeping stable cargo transportation while ensuring the equilibrium state at the end of transportation.

Supplemental material, sj-pdf-1-jdr-10.1177_00220345221088214 for Dual Functions of MDP Monomer with De- and Remineralizing Ability by H. Zheng, Y. Shi, L. Bi, Z. Zhang, Z. Zhou, C. Shao, D. Cui, X. Cheng, R. Tang, H. Pan, Z. Wu and B. Fu in Journal of Dental Research

Quantum materials display rich and myriad types of magnetic, electronic, and structural ordering, often with these ordering modes either competing with one another or 'intertwining', that is, reinforcing one another. Low dimensional quantum materials, influenced strongly by competing interactions and/or geometric frustration, are particularly susceptible to such ordering phenomena and thus offer fertile ground for understanding the consequent emergent collective quantum phenomena. Such is the case of the quasi-2D materials R4Ni3O10(R=La, Pr), in which intertwined charge-and spin-density waves (CDW and SDW) on the Ni sublattice have been identified and characterized. Not unexpectedly, these density waves are largely 2D as a result of weak coupling between planes, compounded with magnetic frustration. In the case of R=Pr, however, we show here that exchange coupling between the transition metal and rare earth sublattices upon cooling overcomes both obstacles, leading to a dimensional crossover into a fully 3D ordered and coupled SDW state on both sublattices, as an induced moment on notionally nonmagnetic Pr3+ opens exchange pathways in the third dimension. In the process, the structure of the SDW on the Ni sublattice is irreversibly altered, an effect that survives reheating of the material until the underlying CDW melts. This 'bootstrapping' mechanism linking incommensurate SDWs on the two sublattices illustrates a new member of the multitude of quantum states that low-dimensional magnets can express, driven by coupled orders and modulated by frustrated exchange pathways., Comment: 48 pages including supplementary, 6 figures, 19 supplementary figures

Supplemental material, sj-docx-1-jdr-10.1177_00220345221077202 for Dlx3 Ubiquitination by Nuclear Mdm2 Is Essential for Dentinogenesis in Mice by H. Zheng, J. Fu, Z. Chen, G. Yang and G. Yuan in Journal of Dental Research

This paper investigates spacecraft orbital boost maneuver by a fully insulated electrodynamic tether using a coupled multiphysics dynamic model that considers electric-magnetic-dynamic energy coupling. The current-potential characteristics of the electrodynamic tether is described by a simplified analytical model, where revised Parker-Murphy model is employed to evaluate electric current generation at plasma contactors together with libration dynamics of tether. The 13th-order Earth's magnetic field model is used to account influence of inhomogeneity of Earth's magnetic field on orbital parameters of electrodynamic tether system, especially in inclined orbits. Parametric analysis has been conducted for orbital boost maneuver from 400 km to 1,200 km at four different orbital inclinations. The results show that (i) the orbit of electrodynamic tether system will change from circular to elliptical orbits, especially in inclined orbits, (ii) the voltage of onboard power supply at the anode affect electric current generation, (iii) the coupled multiphysics model is necessary to characterize the interaction of electrodynamic tether with the surrounding space environment and the controllability of electric current in electrodynamic tether, (iv) the motion of orbital boost maneuver by electrodynamic tether is stable, which is different from the deorbit by electrodynamic tether.

This paper studies the flight dynamics and control strategy for electric solar wind sails based on the nodal position finite element method, where the coupling effects between tether dynamics and t...

Upland rice has the characteristics of strong drought tolerance and wide adaptability. Cultivating upland rice with high yield and high quality can solve the contradiction between food shortage, water shortage, and population increase in countries all over the world, and is of great significance to the sustainable development of agriculture. In this study, high-throughput sequencing technology based on the Illumina Miseq platform was used to investigate the structure and diversity of endophytic bacterial communities using 12 upland rice variety seeds from different areas in Yunnan Province of China as materials. This study aims to reveal the "core microbiota" of the endophytic bacteria in upland rice seeds in the Yunnan Province of China by examining their diversity and community structures. The results showed that 39 endophytic OTUs were found to coexist in all samples. At the phylum level, the first dominant phyla in the 12 seed samples were Proteobacteria (66.92-99.98%). At the genus level, Pantoea (9.75-99.24%), Pseudomonas (0.11-37.24%), Curtobacterium (0.01-19.90%), Microbacterium (0.01-14.95%), Methylobacterium (0.40-5.86%), Agrobacterium (0.01-4.53%), Sphingomonas (0.04-1.56%), Aurantimonas (0.01-1.45%) and Rhodococcus (0.11-1.09%) served as the dominant genera that coexisted in all the upland rice seeds tested and represent the core microbiota in upland rice seeds. Through the correlation analysis with upland rice habitat environmental factors, the effects of climate and altitude on the structure and diversity of endophytic bacterial community in upland rice seeds were further revealed. The results showed that environmental factors such as temperature, precipitation and altitude have great influences on the structure of endophytic bacterial community in upland rice seeds. This study is of great significance to explore the relationship between upland rice and its endophytic bacteria and to tap the resources of drought-tolerant bacteria to improve the yield of local upland rice.

Purpose There is limited and inconsistent evidence about the relationships of erythrocyte polyunsaturated fatty acids (PUFAs) with stroke and stroke types, particularly in China where the stroke rates are high. We aimed to investigate the associations of different erythrocyte PUFAs with incidence of total stroke, ischemic stroke (IS), and intracerebral hemorrhage (ICH) in Chinese adults. Methods In the prospective China Kadoorie Biobank, erythrocyte PUFAs were measured using gas chromatography in 10,563 participants who attended 2013–14 resurvey. After a mean follow-up of 3.8 years, 412 incident stroke cases (342 IS, 53 ICH) were recorded among 8,159 participants without prior vascular diseases or diabetes. Cox regression yielded adjusted hazard ratios (HRs) for stroke associated with 13 PUFAs. Results Overall, the mean body mass index was 24.0 (3.4) kg/m2 and the mean age was 58.1 (9.9) years. In multivariable analyses, 18:2n–6 was positively associated with ICH (HR = 2.33 [95% CIs 1.41, 3.82] for top versus bottom quintile, Ptrend = 0.007), but inversely associated with IS (0.69 [0.53,0.90], Ptrend = 0.027), while 20:3n-6 was positively associated with risk of IS (1.64 [1.32,2.04], Ptrend Pnonlinear = 0.002) and total stroke (Pnonlinear = 0.008), with a threshold at 0.70%. After further adjustment for conventional CVD risk factors and dietary factors, these associations remained similar. Conclusion Among relatively lean Chinese adults, erythrocyte PUFAs 18:2n–6, 20:3n–6 and 20:5n–3 showed different associations with risks of IS and ICH. These results would improve the understanding of stroke etiology.

Kagome superconductors with TC up to 7 K have been discovered for over 40 y. Recently, unconventional chiral charge order has been reported in kagome superconductor KV3Sb5, with an ordering temperature of one order of magnitude higher than the TC. However, the chirality of the charge order has not been reported in the cousin kagome superconductor CsV3Sb5, and the electronic nature of the chirality remains elusive. In this paper, we report the observation of electronic chiral charge order in CsV3Sb5 via scanning tunneling microscopy (STM). We observe a 2 × 2 charge modulation and a 1 × 4 superlattice in both topographic data and tunneling spectroscopy. 2 × 2 charge modulation is highly anticipated as a charge order by fundamental kagome lattice models at van Hove filling, and is shown to exhibit intrinsic chirality. We find that the 1 × 4 superlattices form various small domain walls, and can be a surface effect as supported by our first-principles calculations. Crucially, we find that the amplitude of the energy gap opened by the charge order exhibits real-space modulations, and features 2 × 2 wave vectors with chirality, highlighting the electronic nature of the chiral charge order. STM study at 0.4 K reveals a superconducting energy gap with a gap size 2Δ=0.85meV, which estimates a moderate superconductivity coupling strength with 2Δ/kBTC=3.9. When further applying a c-axis magnetic field, vortex core bound states are observed within this gap, indicative of clean-limit superconductivity.

To understand the brain we must relate neurons’ functional responses to the circuit architecture that shapes them. Here, we present a large functional connectomics dataset with dense calcium imaging of a millimeter scale volume. We recorded activity from approximately 75,000 neurons in primary visual cortex (VISp) and three higher visual areas (VISrl, VISal and VISlm) in an awake mouse viewing natural movies and synthetic stimuli. The functional data were co-registered with a volumetric electron microscopy (EM) reconstruction containing more than 200,000 cells and 0.5 billion synapses. Subsequent proofreading of a subset of neurons in this volume yielded reconstructions that include complete dendritic trees as well the local and inter-areal axonal projections that map up to thousands of cell-to-cell connections per neuron. Here, we release this dataset as an open-access resource to the scientific community including a set of tools that facilitate data retrieval and downstream analysis. In accompanying papers we describe our findings using the dataset to provide a comprehensive structural characterization of cortical cell types1–3and the most detailed synaptic level connectivity diagram of a cortical column to date2, uncovering unique cell-type specific inhibitory motifs that can be linked to gene expression data4. Functionally, we identify new computational principles of how information is integrated across visual space5, characterize novel types of neuronal invariances6and bring structure and function together to decipher a general principle that wires excitatory neurons within and across areas7, 8.

This paper studies the deployment control of a spinning hub-spoke tethered satellite formation, which is a challenging issue due to the strong nonlinear coupling between the hub and sub-satellites, and the underactuated nature of the system if no thrust is used for control. The mathematical model of the formation system is established based on the assumption of rigid body of the hub, inextensible tether, and lumped masses of the sub-satellites. Two novel formation deployment controllers are proposed based on tension control and hybrid tension-thrust control strategies, where underactuated sliding mode control and nonsingular terminal sliding mode control method are used, respectively. The adaptive control theory is adopted to estimate the unknown upper bound of the gravitational perturbation caused by the rotation of the system around the hub. It can be proven by the Lyapunov theory that the close-loop systems have bounded and asymptotic stability under these two deployment controllers, respectively. Finally, numerical simulations are conducted to validate the effectiveness and robustness of the proposed controllers.

This paper develops a new Hamiltonian nodal position finite element method for dynamic analysis of spatial flexible cable systems with large deformation. The dynamic governing equation is derived from finite elasticity theory. Logarithmic strain is applied to construct large deformation Hamiltonian canonical equations. An efficient second-order symplectic difference algorithm is built to solve the canonical equations numerically. A large strain conical pendulum system is analyzed numerically by the proposed method, and the numerical results are compared with those retracted from the existing Hamiltonian methods and Livermore Software Technology Corporation: dynamics (LS-DYNA). The proposed method is further verified by two tethered dynamic experiments involving large displacement motion and large deformation. The comparisons and verifications demonstrate that the proposed method is of symplectic conservation, has high accuracy and has stability for calculating flexible cable system dynamics with large deformation.

Cases of copper sulfate poisoning are rarely reported with a higher mortality rate. Herein, we reported a middle-aged man who had a copper sulfate drowning accident at work, resulting in airway damage, respiratory failure, intravascular hemolysis, hemolytic anemia, impaired liver function, and skin and conjunctival damage. After the rapid and effective treatments, including plasma exchange, irrigation under tracheoscopy, blood transfusion, liver and kidney protection and chelation therapy, the patient finally recovered and was discharged from hospital.

Recently, several ATP-binding cassette (ABC) importers have been found to adopt the typical fold of type IV ABC exporters. Presumably, these importers would function under the transport scheme of “alternating access” like those exporters: cycling through conformations of inward-open, occluded, and outward-open. Understanding how the exporter-like importers move substrates in the opposite direction requires structural studies in all the major conformations. To shed light on that, here we report the structure of yersiniabactin importer YbtPQ from uropathogenic Escherichia coli in the occluded conformation trapped by ADP-vanadate (ADP.Vi) at 3.1Å resolution determined by cryo electron microscopy. The structure shows unusual local rearrangements in multiple helices and loops in its transmembrane domains (TMDs). In addition, the dimerization of nucleotide-binding domains (NBDs) promoted by the vanadate trapping is highlighted by the “screwdriver” action happening at one of the two hinge points. These structural observations are rare and thus provide valuable information to understand the structural plasticity of the exporter-like ABC importers.

As one of the most elegant biological processes developed in bacteria, the siderophore-mediated iron uptake demands the action of specific ATP-binding cassette (ABC) importers. Although extensive studies have been done on various ABC importers, the molecular basis of these iron-chelated-siderophore importers are still not fully understood. Here, we report the structure of a ferrichrome importer FhuCDB from Escherichia coli at 3.4Å resolution determined by cryo electron microscopy. The structure revealed a monomeric membrane subunit of FhuB with a substrate translocation pathway in the middle. In the pathway, there were unique arrangements of residues, especially layers of methionines. Important residues found in the structure were interrogated by mutagenesis and functional studies. Surprisingly, the importer’s ATPase activity was decreased upon FhuD binding, which deviated from the current understanding about bacterial ABC importers. In summary, our studies not only reveal a new structural twist in the type II ABC importer subfamily, but also provide biological insights in the transport of iron-chelated siderophores.

Background Beclin1 is involved in numerous biological processes, including autophagy, stress, senescence, and death. This article aims to clarify the roles of Beclin1 expression in lung carcinogenesis and subsequent progression. Methods The Beclin 1 expression was examined in lung cancer and compared it with clinicopathological parameters and survival data of the cancers using a large number of lung cancer samples. Additionally, we observed the effects of forced Beclin 1 overexpression and its silencing on the proliferation, glucose metabolism, apoptosis, autophagy, invasion, migration, lamellipodia formation, and chemoresistance of lung cancer cells and analyzed the relevant mechanisms. Finally, in vivo effects of Beclin 1 overexpression on tumor growth was determined in nude mice. Results Beclin 1 reversed aggressive phenotypes in SQ-5 and KJ cells with Bcl-2, HSP90, and β-catenin underexpression, LC-3B, ADFP, p-p38, and cytochrome c hyperexpression. The effect of Beclin 1 silence was opposite in H446 cells. In vivo and in vitro Beclin 1-mediated chemoresistance to cisplatin was close with the apoptotic level and NF-кB activation. Beclin 1 overexpression suppressed tumor growth of lung cancer by decreasing proliferation and inducing apoptosis and autophagy. Beclin 1 expression was down-regulated in lung cancer at both mRNA and protein levels. A higher level of Becn1 mRNA was detectable in adenocarcinoma than squamous cell carcinoma (p

Objective: There is still no consensus on the time period of wearing protective collar after Anterior Cervical Discectomy and Fusion (ACDF). We aim to investigate the optimal time period of wearing collar after ACDF. Methods: We retrospectively reviewed patients with cervical spondylosis who underwent one or two segment ACDF during January 2016 and December 2017, and included 97 patients who met inclusion and exclusion criteria. Patients were divided into three groups, 1-4 week group, 5-8 week group and 9-12 week group, according to the actual time period of wearing collar after ACDF. We analyzed Japanese Orthopedic Association (JOA) score, Axial Symptom (AS) score and Neck Disability Index (NDI) before surgery and at post-operative 3 months to investigate the optimal time period of wearing collar after ACDF procedure. Results: 1) JOA score: All three groups have a better post-operative JOA score compared with that before surgery (paired t test, p0.05). 2) AS score: The post-operative AS scores of 1-4 week group and 5-8 week group were significantly better than that before surgery (paired t test, p>0.05). While the post-operative AS score of 9-12 week group was significantly worse than preoperative AS score (paired t test, p

The type VI secretion system (T6SS) is a double-tubular toxin-injection nanomachine widely found in gram-negative human and plant pathogens. The current model depicts that the T6SS spear-like Hcp tube is powered by the contraction of an outer sheath to drill through the envelope of a neighboring cell, achieving cytosol to cytosol delivery. However, gram-positive bacteria seem to be impenetrable to such T6SS action. Here we report that a plant pathogen Acidovorax citrulli (AC) deploys a highly potent T6SS to kill a range of bacteria including Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Mycobacterium smegmatis as well as fungal species including Candida albicans and Pichia pastoris. Using bioinformatic and biochemical assays, we identified a group of T6SS effectors and characterized one effector RhsB that is critical for interspecies interaction. We report that RhsB contains a conserved YD-repeat domain and a C-terminal nuclease domain. Toxicity of RhsB was neutralized by its downstream immunity proteins through direct interaction. RhsB was cleaved at the C-terminal end and a catalytic mutation within the internal aspartic protease abolished such cleavage. Collectively, the T6SS of AC displays potent activities to penetrate the cell envelope barriers of gram-positive and fungal species, highlighting the greatly expanded capabilities of T6SS in modulating microbiome compositions in complex environments.

This paper studies the control of geometric profile of a librating electrodynamic tether by model predictive control using the induced electric current in tether only. First, a high-fidelity multiphysics model of an electrodynamic tether system is built based on the nodal position finite element method and the orbital-motion-limited theory. Second, a state estimator is proposed to estimate the geometric profile of a librating electrodynamic tether, where only the positions and velocities at the tether ends are measurable. The non-measurable geometric profile of tether between two ends is estimated by the high-fidelity multiphysics model with the input of the measurement at tether ends in the spatial domain. To avoid the singularity or ambiguity in the estimation, the geometric profile of tether is then propagated in the time domain by the extended Kalman filter. Third, the problem of controlling the geometric profile of a librating electrodynamic tether is converted into a trajectory tracking problem of the underactuated electrodynamic tether system, where the induced electric current in the tether is the only control input. The control input is optimized by the model predictive control method subject to the output and input control constraints. The numerical simulation results show that the proposed approach is capable of effectively controlling the shape of the liberating electrodynamic tether to the reference trajectory.

Upland rice has the characteristics of strong drought tolerance and wide adaptability. Cultivating upland rice with high yield and high quality can solve the contradiction between food shortage, water shortage, and population increase in countries all over the world, and is of great significance to the sustainable development of agriculture. This study aims to reveal the "core microbiota" of the endophytic bacteria in upland rice seeds in the Yunnan Province of China by examining their diversity and community structures. Through the correlation analysis with upland rice habitat environmental factors, the effects of climate and altitude on the structure and diversity of endophytic bacterial community in upland rice seeds were further revealed. In this study, high-throughput sequencing technology based on the Illumina Miseq platform was used to investigate the structure and diversity of endophytic bacterial communities using 12 upland rice variety seeds from different areas in Yunnan Province of China as materials. Here, 39 endophytic OTUs (0.68%) were found to coexist in all samples. At the phylum level, the first dominant phyla in the 12 seed samples were Proteobacteria (66.92–99.98%). At the genus level, Pantoea (9.75–99.24%), Pseudomonas (0.11–37.24%), Curtobacterium (0.01–19.90%), Microbacterium (0.01–14.95%), Methylobacterium (0.40–5.86%), Agrobacterium (0.01–4.53%), Sphingomonas (0.04–1.56%), Aurantimonas (0.01–1.45%) and Rhodococcus (0.11–1.09%), which represent the core microbiota in upland rice seeds, served as the dominant genera that coexisted in all the upland rice seeds tested. Environmental factors such as temperature, precipitation and altitude have great influences on the structure of endophytic bacterial community in upland rice seeds. This study is of great significance to explore the relationship between upland rice and its endophytic bacteria and to tap the resources of drought-tolerant bacteria to improve the yield of local upland rice.