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Objective. A body movement involves the complicated information exchange between the central and peripheral systems, which is characterized by the dynamical coupling patterns between the multiple brain areas and multiple muscle units. How the central and peripheral nerves coordinate multiple internal brain regions and muscle groups is very important when accomplishing the action. Approach. In this study, we extend the adaptive directed transfer function to construct the time-varying networks between multiple corticomuscular regions, and divided the movement duration into different stages by the time-varying corticomuscular network patterns. Main results. The inter dynamical corticomuscular network demonstrated the different interaction patterns between the central and peripheral systems during the different hand movement stages. The muscles transmit bottom-up movement information in the preparation stage, but the brain issues top-down control commands and dominates in the execution stage, and finally the brain’s dominant advantage gradually weakens in the relaxation stage. When classifying the different movement stages based on time-varying corticomuscular network indicators, an average accuracy above 74% could be reliably achieved. Significance. The findings of this study help deepen our knowledge of central-peripheral nerve pathways and coordination mechanisms, and also provide opportunities for monitoring and regulating movement disorders.

By considering a 3-mode optomechanical system formed by two cavities interacting with a common mechanical mode, we demonstrate that phonon-counting measurements lead to a significant enhancement of entanglement in the output of the two cavities. This conclusion still holds for an inefficient detector, but the dependence on system parameters changes qualitatively from the ideal limit of perfect projective measurements. We find non-trivial optimal points for the entanglement as functions of detector efficiency, measurement outcome, and optical drive strengths. We characterize both the highest achievable entanglement as well as a ‘typical’ value, obtained at the most likely measurement outcome. Numerical results are well understood within an approximate analytical approach based on perturbation theory around the ideal detector limit.

Multidirectional monitoring is highly expectable for stretchable strain sensors by which the randomly orientated cracks or the maximum strain of all directions need to be accommodated. Many current types of research exploit laminated sensors and rosette designs to obtain the desired behavior in several discrete directions. However, this can lead to complex fabricating and resolving processes, as well as significant measurement errors. Our work proposes an isotropic stretchable strain (ISS) sensor that utilizes the in-plane curved sensing film from graphene/silver nanowires (AgNWs), which exhibits uniform sensitivity in all directions within 30∘ and the potential extending to 360∘. The ISS sensor, whose curved shape is optimized based on splines and the quantitative sensing model, is fabricated by a flash stamp machine and followed by vacuum filtration. Experimental results show that the ISS sensor possesses equivalent sensing properties in 30∘ with excellent linearity and durability. Thus our customized sensor is applied to multidirectionally monitor the stretchable surface without consideration for the sensor orientation and the resolving process. Most importantly, the ISS sensor and its design method provide an efficient route for future sensor design with expected properties, not limited to isotropy.

Objective. The study aimed to investigate the physicochemical properties of titanium surfaces with different morphologies stored in a saline solution and their effects on osteoblast behavior. Methods. Freshly prepared commercial pure titanium (cp-Ti), acid-etching titanium (SLA-Ti) and nanowire titanium (NW-Ti) were stored in 0.9% and 10% NaCl solutions, and exposure to air and double-distilled water were used as controls. After storage for two weeks, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), optical contact angle instrument, and optical profilometer were used to analyze the micro-morphology, elemental composition of the samples, contact angle and surface roughness. BCA protein kit was used to detect the protein adsorption capacity of the three titanium surfaces under the different storage conditions. MC3T3-E1 osteoblast-like cells were cultured on the titanium surfaces. The proliferation, adhesion, alkaline phosphatase activity, and osteogenic differentiation of MC3T3-E1 cells were assessed using CCK-8, laser confocal microscope (CLSM), alkaline phosphatase (ALP) assay, and western blotting. Results. SEM results indicated that the storage conditions did not affect the micromorphology of the titanium surfaces. The XPS and contact angle determination results suggested that cp-Ti, SLA-Ti, and NW-Ti stored in NaCl solutions showed less carbon contamination, higher hydrophilicity. The roughness results showed that the air groups and 10% NaCl had higher roughness. The protein adsorption capacity of the three titanium surfaces was significantly improved under storage in 0.9% NaCl. The proliferation activity of osteoblasts on the three titanium surfaces was not different from the control groups after storage in 0.9% NaCl solution. However, the results of the in vitro study suggested that the cell adhesion capacity and the expression of ALP and the osteogenic-related proteins Runx2, Osterix, and Osteocalcin improved after storage in 0.9% NaCl solution. Conclusions. The storage of the different types of titanium surfaces in 0.9% NaCl solution could effectively reduce carbon contamination, maintain good hydrophilicity, improve the roughness and make the environment conducive to the differentiation of osteoblasts.

This study aimed to the preparation of a storage solution containing zinc sulfide particles encapsulated in bovine serum albumin (ZnS@BSA) and its application to improve surface characteristics and osteocompatibility of pure and SLA titanium surfaces. The analysis of surface characteristics including surface topography, elemental distribution and protein amounts confirmed that ZnS@BSA particles were successfully adsorbed on the two titanium surfaces without changing the original morphology. Assays of wettability showed that titanium surfaces preserved in ZnS@BSA solution had superior hydrophilicity compared with control groups. In vitro experiments demonstrated that the titanium surfaces preserved in ZnS@BSA solution significantly promoted the proliferation, adhesion and differentiation of MC3T3-E1 cells. The study therefore concluded that the ZnS@BSA solution could improve the bioactivity of titanium surface and exhibit the potential to be a new type of titanium implant storage solution.

Diffracted vortex beams carrying stable tilted total orbital angular momentum (OAM) vector with respect to the propagation direction are generated, when a linearly polarized Laguerre-Gaussian laser pulse impinges on a solid plasma grating target as shown in the particle-in-cell simulation. The diffracted beams are space-separated in the corresponding diffraction directions. It is found that the transverse OAM results from the rotation of the transverse momentum of the vortex harmonics, and can be modulated by the grating period. The stable average transverse OAM provides us deeper insight to the vortex property of light and may provide an additional controllable parameter for potential applications.

Very rich nitrogen concentration with the dominant C centres and some A centres are found in diamonds grown from a Fe90Ni10-C-high-content NaN3 additive system. The concentrations of C centres rapidly increase with increasing content of NaN3 additive, while the concentrations of A centres increase slowly. The total nitrogen concentration tends to increase rapidly with increasing content of NaN3 additive when the content of NaN3 is below 0.7 wt%. However, the total concentration of nitrogen in the diamonds increases slowly when the content of NaN3 is further increased up to 1.0 wt%, and the total nitrogen average concentration are calculated to be around 2230 ppm for most of the analysed synthetic diamonds. Furthermore, the nitrogen impurities in different crystal sectors of the diamonds are inhomogeneously distributed. The nitrogen impurities in the diamonds in [111] zones are incorporated more easily than that in [100].

Stainless steel Fe-21Cr-6Ni-9Mn (SS 21-6-9), with similar to 21% Cr, similar to 6% Ni, and similar to 9% Mn in weight percentage, has wide applications in extensive fields. In the present study, SS 21-6-9 is compressed up to 250 GPa, and its crystal structures and compressive behaviors are investigated simultaneously using the synchrotron angle-dispersive x-ray diffraction technique. The SS 21-6-9 undergoes a structural phase transition from fcc to hcp structure at similar to 12.8 GPa with neglectable volume collapse within the determination error under the quasi-hydrostatic environment. The hcp structure remains stable up to the highest pressure of 250 GPa in the present experiments. The antiferromagnetic-to-nonmagnetic state transition of hcp SS 21-6-9 with the changes of inconspicuous density and structure, is discovered at similar to 50 GPa, and revealed by the significant change in c/a ratio. The hcp SS-21-6-9 is compressive anisotropic: it is more compressive in the c-axis direction than in the a-axis direction. Both the equations of states (EOSs) of fcc and hcp SS 21-6-9, which are in accordance with those of fcc and hcp pure irons respectively, are also presented. Furthermore, the c/a ratio of hcp SS 21-6-9 at infinite compression, R infinity, is consistent with the values of pure iron and Fe-10Ni alloy.

In this paper, the output quantum correlations of three fields interacting with inverted Y-type atoms inside a three-mode cavity are investigated. By numerically calculating the stationary noise spectra of the fields, we show that it is possible to generate the genuine tripartite continuous variable entanglement outside the cavity by coherently preparing the atoms in a superposition of the upper excited state and two ground states initially. Our numerical results demonstrate that both zero frequency entanglement and sideband frequency entanglement can be obtained under different initial coherent conditions. In addition, we investigate the thermal fluctuation effects on the quantum entanglement. It is found out that the entanglement occurring in a high frequency regime is more robust against thermal noise than the zero frequency entanglement, which may be useful for quantum communication.

The primary stripper foil's lifetime is very important for high intensity proton accelerators. Besides high temperature, the wrinkle of the stripper foil is also harmful for the lifetime and the injection efficiency. However, the recent wrinkle simulation is still not perfect. In this paper, a new method for wrinkle analysis has been proposed for the first time, which is integrated with the buckling theory. Based on this method, the wrinkle vibration and the maximum wrinkle shape of the normally mounted foil have been simulated. Then, two mounting schemes for reducing the wrinkle have been contrasted. Finally, the foil mounting structure for CSNS has been designed.

Effects of NaN3 added in Fe—C system to synthesize nitric diamond at high pressure and high temperature are investigated. Diamond crystals with high nitrogen concentration are synthesized by the system of Fe—C and NaN3 additive at pressure 5.8 GPa and at temperatures 1750–1780K for 15 min. The synthetic diamond crystals have a cubo-octahedral or octahedral shape with yellowish green or green colour. Some disfigurements are observed on the surfaces of most diamond crystals. The composition and content of inclusions formed by iron in diamond are changed and iron nitride is detected in diamond crystals synthesized with Fe–C–NaN3 additive. As the amount of NaN3 additive increases, Fe3 C decreases and iron nitride increases with α-Fe being nearly constant. Moreover, the nitrogen concentrations in diamond crystals synthesized with 1.5wt% NaN3 additive is up to 2250 ppm in substitutional form.