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In the current study, moringa oleifera extract-loaded nanotechnology-based scaffold was developed for treating calvarial defect healing in a rat model. In Vitro studies including cell viability assay, scanning electron microscopy assay, biodegradation assay, and porosity measurement were used to characterize the scaffolds In Vitro. The healing potential of these constructs were studied in a rat model of calvarial bone defect. Study showed that composite scaffolds loaded with moringa oleifera extract had the highest rate of collagen deposition, new bone formation, and angiogenesis compared with other groups.

In this article, a three-axis attitude manoeuvre spacecraft consisting of a central rigid body and a rotating solar array is studied. The rotating solar array is considered a disturbance to the spacecraft. In the design of the controller, the coupled terms and the rotating solar array are considered a disturbance. The improved extended state observer is proposed by combing the sliding mode observer with the originally extended state observer to estimate the disturbance. The sliding mode control method is adopted to adjust the attitude of the spacecraft. Numerical simulations are presented to demonstrate the outstanding performance of the present observer.

To investigate the features of macrophage-like cell (MLC) characterized by en face optical coherence tomography (OCT) in Behçet's uveitis (BU).The extent of fluorescein vascular leakage (FVL) was graded on a scale of 0-3 (0=none, 1=mild, 2=moderate, 3=severe) for the optic nerve head (ONH), macula and peripheral retina. The 3μm en face OCT slabs on inner limiting membrane of ONH or macular region was used to visualize the MLCs.The MLC densities of BU group in ONH and macular region were significantly higher than the control group (both p0.001). The ONH and macular MLC density were significantly higher in eyes with higher FVL grade and they were positively correlated with FVL score (all p0.001).MLC density was elevated in Behçet's uveitis and it may serve as a noninvasive indicator for the severity of fluorescein leakage and retinal inflammation in Behcet's uveitis.

A dynamic modeling method for a multi-panel structure connected with flexible hinges is proposed in this paper. For the solar array composed of several flexible rectangular panels, the global explicit modal functions of spatial coordinates are obtained by employing the Rayleigh-Ritz method, which are in favor of deriving the lower-dimension discrete dynamic equations and the design of controllers for the system in the further research. The Gram-Schmidt characteristic orthogonal polynomials are adopted to construct the flexible deformation expressions of the solar panel. The Lagrange multipliers are introduced to describe the constraint at flexible hinges. The eigen equation of the multi-panel structure is derived to obtain the natural frequencies and corresponding global modes of the system through the Rayleigh-Ritz procedure. Considering the natural frequency calculated from the finite element method as a reference value, the correctness of the modeling process is validated by comparing results with those obtained from the finite element method. Moreover, a high accuracy of the proposed method are confirmed by a very good agreement between results from ANSYS and the theoretical method proposed here. The proposed method derives analytical global modes of the whole system which can be conveniently used to design the controller and work out the nonlinear dynamic model and with a few degree-of-freedoms directly. Finally, the interesting mode interchanged phenomenon is observed with the variation of the stiffness of the rotation spring at flexible hinges.

We present a general methodology for the nonlinear dynamical modeling of a three-axis stabilized spacecraft equipped with flexible solar arrays. The large-span multi-panel solar arrays are modeled as flexible thin plates that are connected to the rigid central body of the spacecraft by means of nonlinear flexible hinges. We construct a low-dimensional yet accurate dynamical model by using a Galerkin expansion in terms of global modes of the system that we compute first by using the Rayleigh-Ritz method. The hinged connections between the rigid and flexible parts of the system are imposed by means of Lagrange multipliers. We use the model to study the spacecraft response triggered by various maneuvering scenarios. We in particular focus on the coupling between vibrations of the flexible components and the rigid motion of the spacecraft induced by hinge nonlinearities during these orbital and attitude maneuvering operations. In all cases considered we find that four global modes are sufficient to accurately compute the system’s response. We also observe other complicated nonlinear dynamical phenomena such as hysteresis and superharmonic resonance that may be of concern in spacecraft design. Our modeling approach can straightforwardly be applied to other multibody systems.

The rigid-flexible-thermal coupling dynamic analysis for a spacecraft in orbit is studied in this paper. The spacecraft consists of a central rigid platform and two groups of lateral solar arrays. There exists the relative motion between the rigid platform and solar arrays, thus the spacecraft is a multi-rigid-flexible bodies coupling system. As the spacecraft in orbit experience different light areas, alternations of the heat flux on solar arrays can result in changes of dynamic characteristics. Considering thermal stress effects of solar arrays, the dynamical model of the spacecraft is established by using Hamiltonian principle. Further, multi-rigid-flexible coupling modes of the system are obtained. The finite difference method is developed to obtained the responses of the spacecraft and the variation of temperature gradients under the different solar radiation. Results of natural characteristics illustrate that constrained modes can be used to discrete the system directly and efficiently. Modal shapes and parameters analysis reveal the rigid-flexible coupling effects of such spacecraft. The thermal-structural analysis demonstrates the thermal alternation may induce the vibration and even change the original vibration of the spacecraft.

The dynamical model of multiple honeycomb plates connected by hinges, including the thermal–structural coupling effect, is investigated in this paper. Under the assumption of small deformations and strains, the classical plate theory is used to establish the dynamical model of the honeycomb plate. The Chebyshev polynomial is adopted to describe the deformation of the plate and the linear torsional spring to represent the elastic hinge. Using the Rayleigh–Ritz method, the characteristic equation of the honeycomb sandwich structure is derived, from which the natural frequencies are obtained. Considering the thermal effect of the plate, the thermal–structural coupling dynamical equation is obtained. The thermal conduction in the thickness direction is calculated by the finite difference method. The present model is validated by comparing with the result generated by an equivalent orthotropic plate model established by the finite element (FE) software MSC Patran. The response analysis reveals the important effect of the metal skin and the hinge stiffness on the dynamic characteristics of the honeycomb sandwich structure. Numerical simulations reveal thermal–structural coupling features for the multi-honeycomb-plate structure from the perspective of the change in dynamic characteristics and the distribution of the temperature gradient. The thermal–structural coupling calculation method adopted herein can be used to solve the thermal conduction of the plate. It serves as the theoretical method for analyzing the dynamical behavior of the solar panel subjected to the solar heat.

The dynamical model for the spacecraft with multiple solar panels and the cooperative controller for such spacecraft are studied in this paper. The spacecraft consists of a rigid platform and two groups of flexible solar panels, where solar panels could be driven to rotate by the connecting shaft. The flexible solar panel involves the use of the orthogonal polynomial in two directions to describe its elastic deformation. By using the Rayleigh–Ritz method, the characteristic equation is derived to obtain natural frequencies and modal shapes of the whole spacecraft. Then the discrete rigid-flexible coupled dynamical equation of the spacecraft is obtained by using the Hamiltonian principle. The equation involves the coupling of the attitude maneuver, solar panels’ driving and vibration suppression. These dynamical behaviors are addressed by the rigid-flexible coupled mode for the first time in this paper. Based on the dynamical equation, the cooperative control scheme is designed by combing the proportional-differential and robust control method. Numerical results show the accuracy of the present modelling method and the validation of the control strategy. The modal analysis implies the complex rigid-flexible coupled characteristic between the central platform and flexible solar panels. The proposed control scheme can maintain the attitude stability while solar panels are being driven, as well as the vibration suppression of flexible solar panels.

To improve the effectiveness of teaching evaluation is an important objective at all teaching institutions. As a direct teaching assessment method, the core task of the evaluation is to elicit genuine and conscientious ratings and comments from students. However, the existing non-trivial teaching evaluation practices cannot assure students’ true anonymities as well as fall short at motivating students to perform high quality evaluations. Therefore, efforts on improving the effectiveness of teaching evaluation hit a bottleneck. In this paper we give and discuss our insights on how to use the blockchain technology and a regulated token economy to address these two issues in order to remove the bottleneck. We also offer our visions on the implementation details of the approach based on our insights.

BACKGROUND Proliferative diabetic retinopathy (PDR) is a leading cause of blindness. This study aimed to analyze the expression of the erythropoietin receptor (EpoR) in patients with PDR and its correlation with postoperative visual prognosis. METHODS Between May 2016 and May 2017, 89 patients who underwent vitreoretinal surgery (VRS) in Affiliated Hospital of North Sichuan Medical College were enrolled. Among them, 45 patients (52 eyes) with PDR and 44 patients (50 eyes) with retinal vein occlusion (RVO) made up the study group and the control group, respectively. All patients received 25G standard flattened three-channel lens-preserving VRS; all procedures were performed by the same physician. Recovery and change in best corrected visual acuity (BCVA) were observed. Subsequently, the patients were divided into group A (improved vision) and group B (no improvement in vision). The integrated optical density (IOD) value of EpoR expression among the groups were compared. Pearson's correlation analysis was used to analyze the correlation between the IOD values of EpoR and the change in visual acuity after surgery for PDR. RESULTS The IOD value of EpoR in the study group was higher than that in the control group (P

Accumulating evidence suggests long-lasting impairments in brain development and cognition caused by neonatal exposure to general anesthetics. To date, very little is known about potential abnormal psychiatric manifestations attributable to neonatal anesthesia. In this study, we used ketamine to induce anesthesia in neonatal mice. By applying mild stressors one day before behavioral tests, we found that adult mice exhibit significant anxiety-like behaviors that were indistinguishable at basal level. Recruitment of AMPA (a-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) type glutamate receptors into silent synapses is a prominent cellular process during neonatal neurodevelopment. We found that exposure to ketamine significantly disrupted synapse unsilencing, and impaired the expression of unsilencing-mediated long-term potentiation (LTP). Pharmacologically enhancement of neural activities by AMPAkine drug CX546 [1-(1,4-benzodioxan-6-ylcarbonyl) piperidine] effectively rescued disrupted developmental synapse unsilencing and LTP at neonatal age, and prevented stressor-evoked anxiety-like behaviors in adult mice. Together, our results indicate that neonatal exposure to ketamine may predispose individuals for psychiatric conditions via disrupting synapse unsilencing, and potentiation of neural activities during the anesthesia-recovery period may be an effective approach to manage adverse effects on brain development. This article is part of the special issue on 'Stress, Addiction and Plasticity'.

An analytical dynamic model for a three-axis attitude stabilized large scale flexible spacecraft (LSFS) installed with hinged solar arrays is established. The natural property of the LSFS is investigated by simplifying it as a rigid central body hinged with two sets of multi-panel structures in this paper. The Gram-Schmidt process is used to construct a set of characteristic orthogonal polynomials as the displacement field of the solar panel. Lagrange multipliers are introduced to describe the constraints at hinges. For the model of LSFS, the Rayleigh-Ritz method is employed to obtain analytical global modes which are explicitly functions of space coordinates and effective for the modeling of lower-order discrete dynamic equations and design of active vibration controllers for the system. Moreover, the method is applied to investigate the parametric influence on natural characteristics for the LSFS. The paper develops a novel method to obtain rigid-flexible coupling global modes and construct the low-dimensional dynamical model for LSFS and study the rigid-flexible coupling dynamic response of in-orbit LSFS with complicated external excitation.

Central sensitization represents a key mechanism mediating chronic pain, a major clinical problem lacking effective treatment options. LIM-domain kinases (LIMKs) selectively regulate several substrates, e.g. cofilin and cAMP response element-binding protein (CREB), that profoundly affect neural activities, such as synaptogenesis and gene expression, thus critical in the consolidation of long-term synaptic potentiation and memory in the brain. In this study, we demonstrate that LIMK deficiency significantly impaired the development of multiple forms of chronic pain. Mechanistic studies focusing on spared nerve injury (SNI) model reveal a pivotal role of LIMKs in the up-regulation of spontaneous excitatory synaptic transmission and synaptogenesis after pain induction. Depending on the pain induction methods, LIMKs can be transiently activated with distinct time courses. Accordingly, pharmacological inhibition of LIMKs targeting this critical period remarkably attenuated central sensitization in the spinal cord and alleviated pain behaviors. We propose selectively targeting LIMKs during their activation phase as a potential therapeutic strategy for clinical management of chronic pain, especially for chronic pain with predictable onset and development time courses, such as chronic post-surgical pain (PSP).

Synaptic scaling is the most extensively studied form of homeostatic plasticity critically involved in various brain functions. Although it is accepted that synaptic scaling is expressed through postsynaptic accumulation of AMPA receptors (AMPARs), the key signaling molecules triggering the induction machinery that mediates synaptic upscaling remains elusive. In this study, we have identified the neurite growth promoting factor 2 (NGPF2), for the first time, as a key signal that triggers synaptic up-scaling. First, we showed that TTX treatment induced rapid but transient release of NGPF2, which peaked within 2 hours after TTX treatment and then gradually declined. Second, we showed that NGPF2 was necessary for scaling up and this requirement was also transient being only required for the first few hours of TTX treatment. Third, we showed that the application of NGPF2 to cultured neurons was sufficient to enhance synaptic strength, which occluded TTX induced scaling up, and that the degree of synaptic scaling was correlated with the duration of NGPF2 treatment. Fourth, we showed that inhibition of various components in the anaplastic lymphoma kinase (ALK)-LIMK-cofilin signaling pathway block TTX- and NGPF2-induced synaptic scaling up. And finally, we showed that TTX-induced release of NGPF2 was sensitive to the protein synthesis inhibitor, but not transcriptional inhibitor and was partially dependent on fragile X mental retardation protein 1 (FMRP1). These results provide compelling evidence that activity blockade induces NGPF2 protein synthesis and release to trigger synaptic upscaling through LIMK-cofilin dependent actin reorganization, spine enlargement and stabilization of AMPARs at the synapse.

Synaptic scaling is an extensively studied form of homeostatic plasticity critically involved in various brain functions. Although it is accepted that synaptic scaling is expressed through the postsynaptic accumulation of AMPA receptors (AMPARs), the induction mechanism remains elusive. In this study, we show that TTX treatment induces rapid but transient release of the neurite growth-promoting factor 2 (NGPF2), and this release is necessary and sufficient for TTX-induced scaling up. In addition, we show that inhibition of the anaplastic lymphoma kinase (ALK)-LIMK-cofilin signaling pathway blocks TTX- and NGPF2-induced synaptic scaling up. Furthermore, we show that TTX-induced release of NGPF2 is protein synthesis dependent and requires fragile X mental retardation protein 1 (FMRP1). These results indicate that activity blockade induces NGPF2 synthesis and release to trigger synaptic scaling up through LIMK-cofilin-dependent actin reorganization, spine enlargement, and stabilization of AMPARs at the synapse.

The vibration characteristics of a cantilever L-shaped beam perpendicular to the horizontal plane are investigated in this paper. The dynamical model of the L-shaped multi-beam structure is established by using the Euler-Bernoulli beam theory, where vibration equations of each substructure, matching conditions of the connection and boundary conditions are included. Based on the modal orthogonality, the discrete dynamical model with finite degrees of freedom is obtained. Then the distributed piezoelectric energy harvester is proposed to collect the vibration energy of the L-shaped beam. Different the most traditional energy harvester that the piezoelectric material covers the surface of the structure, the distributed energy harvester is placed on the selected points. The genetic algorithm is adopted to obtain the optimal position that can provide the maximum output power. The validation and accuracy of the present model is verified by comparison with the finite element model. Numerical results show the discrete model can perform the dynamic characteristics of the structure well with only two modes. By the comparison of different configurations, it concludes that the optimal position of the distributed piezoelectric energy harvester is close to the fixed end of the whole cantilever structure.

The dynamic modelling approach for the multi-plate structure connected by nonlinear hinges is presented in this paper. The Chebyshev polynomials are employed as admissible basis functions to establish the dynamic model of each plate. The Lagrange multiplier is introduced to describe the restraint effect of the hinge on the plate. In order to show the impact of the hinge on the plate as reasonably as possible, the constraint contains not only the displacement of each plate but also the rotation of adjacent plates. Then based on the Rayleigh-Ritz method, a characteristic equation is derived and natural frequencies of the multi-plate structure are obtained. Considering the cubic nonlinearity and Coulomb friction of the hinge, the discrete dynamic model of the multi-plate structure is established according to the obtained modal shape functions. Comparing the natural frequencies and modal shapes of the analytical model with that of the finite element model, the validity of the present method and the accuracy of the model are demonstrated. Simulation results show that linear modes play an important role in the dynamic analysis. By varying the relevant parameters (structural and excitation's) and conducting a nonlinear response, their effect on the dynamic response of the whole structure is demonstrated.

The natural property of a three-axis attitude stabilized spacecraft is investigated by simplifying it as a rigid central body jointed with 4 solar panels in this paper. For the spacecraft composed of a rigid central body and flexible panels, the Rayleigh-Ritz method is employed to obtain global modes which are explicitly functions of space coordinates and are useful for the modeling of lower-order discrete dynamic equations and design of active vibration controllers for the system. The Gram-Schmidt process is used to construct a set of characteristic orthogonal polynomials as the displacement field of the solar panel. Lagrange multipliers are introduced to describe the constraint at joints. The characteristic equation of the whole system is derived through the Rayleigh-Ritz procedure. Then, natural frequencies and corresponding global modes of the spacecraft with jointed panels are obtained. Taking the natural frequency obtained from the finite element method as a reference value, the process of getting natural frequencies is validated by comparing results obtained with those from the finite element method. Moreover, an excellent convergence and high accuracy of the present method is demonstrated by a very good agreement between results from ANSYS and theoretical method proposed here. Finally, parametric studies on characteristics of the spacecraft are conducted. The interesting mode shift phenomenon is observed when parameters of the spacecraft are changed.

The C-terminal domain of NLG1 is sufficient to enhance spine and synapse number and to modulate synaptic plasticity, and it exerts these effects via its interaction with SPAR and the subsequent activation of LIMK1/cofilin-mediated actin reorganization., Neuroligin (NLG) 1 is important for synapse development and function, but the underlying mechanisms remain unclear. It is known that at least some aspects of NLG1 function are independent of the presynaptic neurexin, suggesting that the C-terminal domain (CTD) of NLG1 may be sufficient for synaptic regulation. In addition, NLG1 is subjected to activity-dependent proteolytic cleavage, generating a cytosolic CTD fragment, but the significance of this process remains unknown. In this study, we show that the CTD of NLG1 is sufficient to (a) enhance spine and synapse number, (b) modulate synaptic plasticity, and (c) exert these effects via its interaction with spine-associated Rap guanosine triphosphatase–activating protein and subsequent activation of LIM-domain protein kinase 1/cofilin–mediated actin reorganization. Our results provide a novel postsynaptic mechanism by which NLG1 regulates synapse development and function.

Background To improve antibiotic use globally, we must deepen our understanding of the public’s knowledge, attitudes and practices (KAP) concerning antibiotics. Children are frequent users of antibiotics, and their caregivers play important roles in determining how antibiotics are used. The purpose of this study was to describe caregivers’ KAP in a rural province in eastern China, and to identify socio-demographic factors associated with inappropriate antibiotic use. Methods A cross-sectional questionnaire based survey was conducted in 12 villages in one county in Shandong Province. A total of 727 individuals who were the primary day-to-day caregiver for a child aged 0–7 years were randomly selected and invited to participate. All caregivers were surveyed face-to-face using a semi-structured questionnaire focusing on the use of antibiotics in children. Results Almost all invited caregivers (99.3 %) completed the questionnaire in full. Caregivers expressed high levels of over-expectation for antibiotics for common childhood symptoms, stating that antibiotics were always or usually necessary when a child has a fever (46 %) or dry cough (42 %). Most caregivers (93 %) were aware that they should follow the doctor’s advice when giving their children antibiotics. Many, however, reported that they had previously deviated from advice; this was most commonly through using antibiotics intermittently rather than regularly, but also by increasing and decreasing doses. Caregivers that were older and that had less formal education had higher levels of self-reported adherence (p

Research questionnaire of knowledge, attitudes and practices of antibiotics among Caregivers in the rural area of Shandong Province. (DOCX 31Â kb)