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Improving the structural stability and the electron/ion diffusion rate across whole electrode particles is crucial for transition metal oxides as next-generation anodic materials in lithium ion batteries. Herein, we report a novel structure of double carbon coated Co3O4 cross-linked composite, where Co3O4 nanoparticle is in-situ covered by nitrogen-doped carbon and further connected by carbon nanotubes (Co3O4 NP@NC@CNTs). This double carbon coated Co3O4 NP@NC@CNTs framework not only endows a porous structure that can effectively accommodate the volume changes of Co3O4, but also provides multidimensional pathways for electronic/ionic diffusion in and among the Co3O4 nanoparticles. As expected, the Co3O4 NP@NC@CNTs electrode exhibits unprecedented lithium storage performance, with high reversible capacity of 1017 mAh g-1 after 500 cycles at 1 A g-1 , and very good capacity retention of 75%, even after 5000 cycles at 15 A g-1. The lithiation/delithiation process of Co3O4 NP@NC@CNTs is dominated by pesudocapacitive behavior, resulting in excellent rate performance and durable cycle stabiltiy. Electrochemical kinetics further reveals a decreased energy barrier for electron/ion transport, synergistically, contributes to its excellent lithium storage performance.

Objectives: To evaluate the pharmacodynamical effects and pharmacological mechanism of Ginsenoside H dripping pills (GH) in chronic unpredictable mild stress (CUMS) model rats.Methods: First, the CUMS-induced rat model was established to assess the anti-depressant effects of GH (28, 56, and 112 mg/kg) by the changes of the behavioral indexes (sucrose preference, crossing score, rearing score) and biochemical indexes (serotonin, dopamine, norepinephrine) in Hippocampus. Then, the components of GH were identified by ultra-performance liquid chromatography-iron trap-time of flight-mass spectrometry (UPLC/IT-TOF MS). After network pharmacology analysis, the active ingredients of GH were further screened out based on OB and DL, and the PPI network of putative targets of active ingredients of GH and depression candidate targets was established based on STRING database. The PPI network was analyzed topologically to obtain key targets, so as to predict the potential pharmacological mechanism of GH acting on depression. Finally, some major target proteins involved in the predictive signaling pathway were validated experimentally.Results: The establishment of CUMS depression model was successful and GH has antidepressant effects, and the middle dose of GH (56 mg/kg) showed the best inhibitory effects on rats with depressant-like behavior induced by CUMS. Twenty-eight chemical components of GH were identified by UPLC/IT-TOF MS. Subsequently, 20(S)-ginsenoside Rh2 was selected as active ingredient and the PPI network of the 43 putative targets of 20(S)-ginsenoside Rh2 containing in GH and the 230 depression candidate targets, was established based on STRING database, and 47 major targets were extracted. Further network pharmacological analysis indicated that the cAMP signaling pathway may be potential pharmacological mechanism regulated by GH acting on depression. Among the cAMP signaling pathway, the major target proteins, namely, cAMP, PKA, CREB, p-CREB, BDNF, were used to verify in the CUMS model rats. The results showed that GH could activate the cAMP-PKA-CREB-BDNF signaling pathway to exert antidepressant effects.Conclusions: An integrative pharmacology-based pattern was used to uncover that GH could increase the contents of DA, NE and 5-HT, activate cAMP-PKA-CREB-BDNF signaling pathway exert antidepressant effects.

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Waveform deformation and breaking are widespread phenomena when internal solitary waves (ISWs) encounter changing topographies, which have been observed in many parts of oceans. In this study, experiments are performed in a series of combinations of bottom step topographies with different heights and ISWs in different amplitudes within a two-layer stratified fluid system. According to experimental results, the evolution processes of ISWs over the bottom step are classified into four typical regimes as the wave–step interaction varying from weak to strong, which are the transmission regime, transitional regime, breaking regime, and reflection regime, corresponding to the evolution patterns of steady passage, deformation, breaking, and strong reflection, respectively. To describe the intensity of wave–step interaction, a new improved interaction parameter is proposed, which takes both relative amplitude of ISWs and relative topography changes into consideration, and achieved better effectiveness in defining the boundaries between different regimes. In terms of energy properties, with the wave–step interaction becoming stronger, the transmission ratio keeps decreasing throughout all regimes, while the reflection wave starts to appear since the breaking regime and its energy keeps increasing. At the critical point between the breaking regime and reflection regime, the reflection ratio equals the transmission ratio, and the energy loss ratio reaches its maximum.

A refined extended alternating convex optimization (REA-CO) method is presented to synthesize multibeam sparse circular-arc antenna arrays with minimum element spacing control by considering real antenna array structure characteristics. This method consists of initial step and a few refining steps. At the initial step, an initial array with dense elements distributed on a circular-arc is considered, and its array manifold vector is described by rotating a simulated isolated element pattern (IEP) without considering element mutual coupling. The collective excitation coefficient vector (CECV) and its energy bound are introduced for each element, and consequently the common element positions for generating desired multibeam patterns can be found by minimizing the number of active CECVs under multiple constraints. This minimization problem is further formulated as performing a sequence of alternating convex optimization (ACO) in which the CECV and an auxiliary weighting vector are alternately chosen as the optimization variables, so that the mimimum element spacing constraint can be easily dealt with. Once the initial optimization step is finished, a few refining steps are performed in which the element positions and excitations are successively updated in each step by renewing the array manifold vector through rotating the simulated nearby active element patterns (AEPs) of the antenna array obtained at the previous step. In such a way, the mutual coupling can be incorporated into the multibeam sparse array synthesis. An example of synthesizing a sparse circular-arc conformal array with 23 beams covering the space from −63.25 • to 63.25 • is conducted to validate the effectiveness and advantage of the proposed method.Index Terms-Sparse circular-arc array, alternating convex optimization, multibeam pattern synthesis, minimum element spacing control Manuscript

The design of propulsion system is a very critical task because it determines the performance of underwater robots, such as maneuverability and endurance and so on. Generally, it is a challenge to develop a propulsion system which can make tradeoff among multiple degree-of-freedom (DOF) motions, simple and compact structure and low power consumption. Thus, we are motivated to propose a collaborative propulsion system for the underwater robot and its unique reconfigurable structure makes vectorial propulsion possible. The novel collaborative propulsion system consists of a Coanda effect based primary system and a magnetic coupling based auxiliary system. Based on Coanda effect, the primary system can provide sufficient thrust in four directions by only one water-jet. Meanwhile, as the assistance of the primary thruster, the auxiliary system can realize omnidirectional thrust to balance the robot whole body and meet the high requirement of maneuverability. In this paper, we present the mechanical structure of the propulsion system in detail and explain specific design of the fluidic valve by theoretical analysis. To evaluate the performance, simulations about jet attachment effect and magnetic coupling characteristic have been conducted at last so as to lay a solid foundation for the feasibility of such novel propulsion system.

Underwater acoustic (UWA) communication has been developing rapidly over the past decades for its crucial position in resource exploration, environmental monitoring, and scientific research. However, the transmission data rate of UWA communication is limited by the narrow bandwidth of the underwater acoustic channel. Here, the generation of quadrature acoustic frequency combs (AFCs) is first reported. Massive parallel channels achieved with multiplexing of AFCs for UWA communication are demonstrated. The generated AFCs have unique characteristics which have a stable and precise division in frequency and time domain simultaneously with carrier spacing of 1 Hz with the stability of 10 −8 . The different frequency spacing in combs leads to different teeth spacings in time, which is orthogonal and separable in the time domain. The orthogonality among AFCs provides a new dimension for multiplexing and can drastically increase channel efficiency. The underwater acoustic communication experiments demonstrate that it is drastically increasing the transmission rate to 45.33 kb s −1 and high spectral efficiency of 1.51 (channel s −1 ) Hz −1 without utilizing other modulation techniques by a single transducer. Since AFCs multiplexing is a completely independent degree of freedom that can be readily integrated with other high order modulation techniques, such as quadrature amplitude modulation and phase-shift keying, in a single channel, AFCs multiplexing opens a new dimension for acoustic communication.