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The concept of diabetes cardiomyopathy (DCM) was first introduced by rubler and his colleagues. DCM refers to the adverse myocardial structure which is associate with diabetes. The primary pathogenesis of diabetes mellitus, insulin resistance, is also a predisposing factor for cardiovascular disease. In addition, diabetic disease is also associated with abnormal cytosolic calcium regulation, systolic dysfunction, cardiac remodeling, myocardial stiffness, and hypertrophy. Diabetic patients are normally affected by cardiovascular disorders. Several diagnosis approaches could be used in DCM, including echocardiography, magnetic resonance imaging (MRI) and nuclear imaging. Given the broad influence and complex mechanism of DCM, effective therapies are urgently needed. Current treatments for DCM are mainly target several critical proteins. Lifestyle interventions for patients with DCM are beneficial as well. DCM has been known by researchers for 50 years, but the relevant signaling pathways and targeted therapies still need further investigation.

The meiotic entry of undifferentiated germ cells is sexually specific and strictly regulated by the testicular or ovarian environment. Germline stem cells with a set of abnormal sex chromosomes and associated autosomes, undergo defective meiotic processes and are eventually eliminated by yet to be defined posttranscriptional modifications. Herein we report the role of gsdf, a member of BMP/TGFβ family uniquely found in teleost, in the regulation of meiotic entry in medaka (Oryzias latipes) via analyses of gametogenesis in gsdf-deficient XX and XY gonads in comparison to their wild-type siblings. Several differentially expressed genes including the FKB506-binding protein 7 (fkbp7), were significantly upregulated in pubertal gsdf-deficient gonads. The increase in alternative pre-mRNA isoforms of meiotic synaptonemal complex gene sycp3 was visualized using Integrative Genomics Viewer and confirmed by real-time qPCR. Nevertheless, immunofluorescence analysis showed that Sycp3 protein products reduced significantly in gsdf-deficient XY oocytes. Transmission electron microscope observations showed that normal synchronous cysts were replaced by asynchronous cysts in gsdf-deficient testis. Breeding experiments showed that the sex ratio deviation of gsdf

As a subtype of kainite receptors (KARs), GluK2 plays a role in the perception of cold in the periphery sensory neuron. However, the molecular mechanism for gluk2 on the cold stress in fish has not been reported. In this article, real-time PCR assays showed that gluk2 was highly expressed in the brain and eyes of adult zebrafish. To study the functions of gluk2, gene knockout was carried out using the CRISPR/Cas9 system. According to RNA-seq analysis, we selected the differentially expressed genes (DEGs) that had significant differences in at least three tissues of the liver, gill, intestine, skin, brain, and eyes. Gene Ontology (GO) enrichment analysis revealed that cry1ba, cry2, per1b, per2, hsp70.1, hsp70.2, hsp70l, hsp90aa1.1, hsp90aa1.2, hspb1, trpv1, slc27a1b, park2, ucp3, and METRNL were significantly enriched in the ‘Response to temperature stimulus’ pathway. Through behavioral phenotyping assay, the gluk2−/− larval mutant displayed obvious deficiency in cold stress. Furthermore, TUNEL (TdT-mediated dUTP Nick-End Labeling) staining proved that the gill apoptosis of gluk2−/− mutant was increased approximately 60 times compared with the wild-type after gradient cooling to 8 °C for 15 h. Overall, our data suggested that gluk2 was necessary for cold tolerance in zebrafish.

Type III antifreeze proteins (AFPIIIs) are a group of small globular proteins found in some polar fishes to protect them against freezing damage. Transgenic expression of AFPs has been shown to confer cold tolerance to commercially important plants and animals. We have previously isolated multiple AFPIII genes in the Antarctic eelpout (Lycodichthys dearborni) that encode larger AFPIII isoforms with up to 12 of the conventional domains. Here we have introduced the fish AFPIII genes that encode for the monomer (ld1), dimer (ld2), trimer (ld3) and tetramer (ld4) AFPIII isoforms in tobacco plants. Pot-grown 4-week-old transgenic tobacco plants were exposed to cold stress at 4 °C for 30 days and the results show that ld1, ld2, ld3 and ld4 transgenic plants present relatively lower electrolyte leakage and lower content of malondialdehyde (MDA), but accumulated higher content of proline when compared to control plants. This indicates considerable improved membrane integrity under low temperature stress and improvement of the plant cold resistance. The plants transformed with the AFPIII tetramer- and trimer-domains demonstrated a higher cold-tolerant levels when compared with plants transformed with the dimer- and monomer AFPIII domains. Our study further supports that fish AFPIIIs, especially the multidomain proteins, protect cells from non-freezing hypothermic stresses, apart from there well-known function as ice inhibitors molecules at freezing temperature.

Sexually dimorphic meiosis is monitored by meiotic recombination to prevent the formation of abnormal gametes in males and females. However, the regulatory mechanism of sex-specific meiotic recombination is not completely understood. Here we report the role of gsdf, a unique BMP/TGF-b family member gene, in the regulation of meiotic recombination in medaka (Oryzias latipes) based on the RNA-seq and cytogenetic analysis of normal and gsdf deficient gametogenesis. Several differentially expressed genes, including the FKB506-binding protein 7 (fkbp7), were significantly upregulated in pubertal gsdf deficient gonads. The escalation of alternative pre-mRNA isoforms of meiotic synaptonemal complex genes including sycp3 were visualized using Integrative Genomics Viewer and confirmed by real-time qPCR. However, immunofluorescence analysis showed that Sycp3 protein products in gsdf deficient XY oocytes were significantly reduced. Transmission electron microscope observations showed that asynchronous cysts replaced normal synchronous cysts in gsdf-deficient testis. Breeding experiments revealed a skewed ratio of gsdf−/− XY gamete fertility in a non-Mendelian manner resulting in XY chromosome non-disjunction. Taken together, our observations suggest that Gsdf signaling may directly or indirectly affect meiotic recombination in the process of sex-specific division of germline stem cells.

Towards the zero-gravity simulation test requirements of spacecraft for on-orbit service missions, the zero-gravity motion simulation technology based on industrial robot was studied. In order to realize the accurate force sensing of load on robot, the BP neural network was used to establish the force prediction model. The model uses the robot pose, acceleration, angular velocity, and angular acceleration as input layer parameters, and uses the data from force/torque sensor on robot wrist as the output layer parameter. In order to realize the accurate force perception in whole working space of the robot, the orthogonal experiment design method was adopted to determine the path points of the robot for sample data collection. Based on the established force prediction model, the accurate force sensing of the end load of the robot under moving conditions is realized. In experiment, for the load with 100kg mass on robot, the maximum error of force sensing is 39.8N, and the root mean square error of force sensing is 9.3N. The maximum error of torque sensing is 18.7Nm, and the root mean square error of torque sensing is 4.4Nm. Furthermore, according to the real-time force sensing results of the robot load, the motion speed of the load in zero-gravity state is calculated by dynamics theory. Then the robot is driven to execute the corresponding motion of the load, and the zero gravity motion simulation of the load is realized.

In lithium-ion batteries, the volume change of anode materials will result in fracture of solid electrolyte interphase (SEI) during continuous lithiation and delithiation. Herein, an analytical model has been developed to determine the fracture mechanism of the SEI and the fatigue in lithium-ion batteries. The evolution of diffusion-induced stresses and concentration have been evaluated. In addition, surface effects are found to effectively reduce the stresses and the crack propagation in SEI during lithiation. With combined energy release rate, the critical thickness of SEI is also established to prevent crack propagation. Finally, the capacity fade of lithium-ion batteries during cycling may be predicted using fatigue model. It is found that the depths of discharge (DODs) are closely related to the capacity fade of lithium-ion batteries. Overall, this work may provide physical understanding for optimized structural design to alleviate the SEI fracture and the fatigue of the lithium-ion batteries.

In this paper, a way to apply vision-guided robots to satellite assembly was studied. Infrared cameras and “inflexible frame” which includes cooperative objectives had been used within the vision system to degree the goal pose. A probe tool become used to obtain convenient measurement of the target factor. Beneath the condition that the corresponding point pair of space is understood, a method for calculating the pose transformation matrix and goal pose of the robotic is given. The experimental consequences show that the measurement matching error of the corresponding hollow position is inside 2. 9mm. The method can meet the engineering implementation necessities for satellite assembly.

Comprehensive first-principles calculations are performed to investigate the effects of the Silicon clusters (Si-CLs) anchored in nitrogen-doped defective graphene hybrid materials on their potential applications as very promising interface energy storing materials in lithium-ion batteries (LIBs). Three different kinds of defective models, graphitic, pyridinic, and pyrrolic graphene have been introduced in our work. First, the stability of Si-CLs deposited on various N-doped graphene (N-G) sheets has been investigated, and their electronic properties have been explored using first-principles theory. Second, single and multiple lithium (Li) atoms adsorption on Si-CLs anchored in N-G have been carried out to test the Li storage performances of the hybrids. Our results confirm that the N-doped pyridinic graphene hybrid is the most suitable material s for Li adsorption among those three different structural graphene sheets. Due to the symmetric vacancy presence, the binding strength of Si-CLs on N-doped defective graphene (N-DG) is much more powerful than that of graphitic one. Furthermore, the Li uptaking ability of Si/graphene (Si-G) is studied by calculating the binding energy of Li atoms. As a result, that N-G not only can be used as a bumper material restricting Si volume expansion, but can also provide extra intercalation places for Li atoms.

In order to realize MoO3 as an anode material in lithium ion batteries, it is important to understand the atomic level mechanisms of MoO3 structures evolution during lithiation. A first-principle method is employed to evaluate the volumetric deformation, electronic structure, and Young’s modulus during lithiation based on density function theory. The electrochemical insertion of Li ions into MoO3 anode materials prompts a volumetric deformation along the perpendicular direction. Moreover, we analyzed the projected density of states during lithiation for MoO3. The band gap will vanish at high enough Li concentration, the electron will dope into Mo atoms by Li interaction. In addition, the migration energy barriers of lithium ions along the z-direction are the lowest among other pathways, while a large deformation caused by lithiation remained in the MoO3 materials. In particular, the Young’s modulus of the MoO3 anode materials increased during lithiation, but the large mechanical strength can sustain this. Those results may reveal the mechanism of structural transition from the MoO3 to Li2MoO3 and provide some valuable mechanical understanding of LixMoO3 materials in lithium ion batteries.

The function and performance of textured polycrystalline thin films are closely related to their microstructures. However, the corresponding growth mechanisms remain unclear, which brings obstacles to the effective engineering of the films' properties. In this work, textured nanocrystalline Indium Oxide (nc-In2O3) thin films are prepared and the growth mechanism is explored. Texture morphology within or beyond the prediction of Wulff's theorem and van der Drift's growth mechanism are both observed. The orientation of the textured film changes from (100)-preferred in quasi-equilibrium growth conditions to (111)-preferred in non-equilibrium growth conditions. From a microscopic perspective of adatoms' diffusion, different growth modes for the growth of the textured In2O3 thin films is classified and a quantitative growth zone model is developed. According to the zone model, the morphology and orientation of the films could be successfully designed and controlled by changing growth conditions. Keywords: Texture crystalline thin film, Indium oxide, Zone model, van der Drift growth mode

According to the characteristics of single small batch and the demand for the automatic installation of spacecraft fasteners, a set of automatic installation system for spacecraft fasteners is developed. This system can independently complete a series of actions, such as fastener grabbing, installation positioning, tightening, measuring force and so on. The screw separating mechanism realizes the single screw sorting and automatically conveys the screw to the installation position by compressed air blowing, the screw is tightened at the installation position by pneumatic sliding table, use electric torque gun to screw in and tighten with constant torque, through the electric torque gun controller to achieve the tightening torque data back collection. Automatic installation test was carried out and the actual tightening torque control precision met the requirements of the torque control precision of the spacecraft fastener installation.

Peg-in-hole assembling structure is a commonly used mechanical structure for automatic assembly of robots in the aerospace field. With the structural constraints between pins and holes, the robot drives the installed equipment. With the force flexibility provided by the robot compliant control algorithm, the device will be installed in place along the guidance of the assembling pin. The traditional manual control method for pin-hole matching is more and more difficult to adapt to the installation of large-size equipment. To solve this problem, this paper proposes an improved force control method that takes into account the influence of contact force between the pegs and holes on impedance controller, and comprehensively considers the influence of elastic contact and friction between pegs and holes, so that it can adapt to the force compliance installation of large-size equipment, and the effectiveness of this method is proved by simulation experiment.

The tribological properties of Al2O3/WS2 composite lubricant were examined by using a ball-on-plate reciprocating sliding wear test configuration utilizing PAO6 base fluid and oleic acid as surfactant. The morphology and chemical composition of the wear tracks were examined by using a scanning electron microscope and a x-ray energy dispersive spectrometer. It was found that the coefficient of friction was reduced by 46.6% after adding 0.5 wt% Al2O3/WS2 composite particles. The wear width and wear depth were reduced by 37% and 59.6% after adding 3 wt% Al2O3/WS2 composite particles. In orthogonal tests, it was proposed that the best tribological performance of Al2O3/WS2 composite lubricant could be achieved while using the normal load of 50 N, frequency of 2 Hz and temperature of 65 °C. Frequency could be considered as the primary factor affecting the tribological properties of compsite lubricant. The excellent lubricating performance could be attributed to the formation of WS2 tribo-film with low shearing resistance, and a portion of the Al2O3 particles were embedded by external force to prevent surface contact between the steel ball and brass plate.

With the technical targets continuously improving, spacecraft components become more large and heavy, such as optical camera, antenna. It is difficult for operators to hold these large-scale components manually through the entire assembly process. This paper aims to propose a path planning method for industrial robot to accomplish automatic assembly of large-scale components in confined space. Base on the CAD model of spacecraft, robot and components etc., a virtual assembly environment is constructed in accordance with the position and pose of the real scene. In the virtual environment, geometric constraint in the assembly process is recognized and collision detection is implemented using the axis-aligned bounding box (AABB) method. After that, probabilistic roadmap method (PRM) is performed to plan an assembly path in 3D space with obstacles. The PRM planner is divided into two phases: the learning phase and the query phase. In the learning phase, a collision-free roadmap is built. In the query phase, the nodes of the roadmap are connected. The A-star algorithm is accomplished to find a feasible path between the initial node and the goal node and then assembly sequences are produced by robot off-line programmer. Experiment results show that this method can rapidly generate a collision-free assembly path, and control robot to safely and efficiently complete large-scale components installation in the confined space.

In this study, the resistive switching performance of amorphous indium–gallium–zinc oxide (a-IGZO) resistive switching random-access memory (ReRAM) was improved by inserting a thin silicon oxide layer between silver (Ag) top electrode and a-IGZO resistive switching layer. Compared with the single a-IGZO layer structure, the SiO2/a-IGZO bi-layer structure exhibits the higher On/Off resistance ratio larger than 103, and the lower operation power using a smaller SET compliance current. In addition, good endurance and excellent retention characteristics were achieved. Furthermore, multilevel resistance states are obtained through adjusting SET compliance current and RESET stop voltage, which shows a promise for high-performance nonvolatile multilevel memory application.

A nonvolatile memory (NVM) based on an amorphous-indium–gallium–zinc oxide (a-IGZO) thin-film transistor (TFT) with defect-engineered gate insulator was demonstrated. The gate insulator was a blocking alumina/storage alumina/tunneling alumina stack structure, which was simply assembled in a single atomic layer deposition step. The memory device showed a positive shift of threshold voltage as large as 14.4 V after +20 V, 1 s programming. In contrast, the memory erasing was not sensitive to negative gate voltage in the dark. Once programmed, the memory can only be light erased. Furthermore, the light combined with a negative bias improved the erasing speed effectively. In addition, a 10-year memory window as large as 7.5 V was extrapolated at room temperature with a charge loss of 34.7%. Based on the observation of blisters in the storage alumina layer after high temperature annealing, Fourier transform infrared spectroscopy measurement and first-principles calculations, the high electron storage capacity can be attributed to the deep defect levels in the storage alumina layer, which were originated from hydrogen impurity. This a-IGZO TFT charge trapping NVM with high performance and simple process is a candidate device for the application of fully functional transparent system on panel.

Bipolar resistive switching properties of Ag/a-IGZO/Pt structure resistive random-access memories (ReRAMs) were investigated. The amorphous In-Ga-Zn-O (a-IGZO) films were prepared by a radio frequency magnetron sputtering system at room temperature in mixed gas ambient of argon (Ar) and oxygen (O2). The oxygen partial pressures during sputtering deposition were varied from 0% to 17% to engineer defects in an a-IGZO layer. When the oxygen partial pressure increased to 17%, forming-free bipolar resistive switching properties were observed with nearly 100% device yield. In addition, the forming-free ReRAM device presents an enhanced resistive switching uniformity and an enhanced endurance. The forming-free resistive switching is attributed to the concentration of oxygen-related defects in an a-IGZO thin film via analyses of x-ray photoelectron spectroscopy and current–voltage (I–V) curves, with which it is possible to reduce the forming energy of silver (Ag) conductive filaments.

In this study, various In2O3 thin films were grown on c-plane sapphire substrates by metal–organic chemical vapor deposition via changing the growth parameters. The structural and electrical properties of the films were investigated by employing the X-ray diffraction (XRD), scanning electron microscopy, conductive atomic force microscopy (CAFM), and Hall Effect measurement. Results revealed that the investigated In2O3 thin films are bcc phase poly-crystalline with preferred orientation along the [100] or [111] direction. Moreover, the existence of two types of grains with different conductivities in the investigated In2O3 thin films was confirmed by CAFM measurement. Interestingly, a positive correlation was found between carrier concentrations and (222)/(400) XRD diffraction peak intensity ratios of the investigated In2O3 thin films. The mechanism of the positive correlation was explained by the difference in impurities concentrations between the two types of grains with the difference crystalline orientations.

We have investigated the electrical performance of amorphous indium–gallium–zinc oxide (α-IGZO) thin-film transistors with various channel thicknesses. It is observed that when the α-IGZO thickness increases, the threshold voltage decreases as reported at other researches. The intrinsic field-effect mobility as high as 11.1 cm 2 /Vs and sub threshold slope as low as ∼0.2 V/decade are independent on the thickness of α-IGZO channel, which indicate the excellent interface between α-IGZO and atomic layer deposited Al 2 O 3 dielectric even for the case with α-IGZO thickness as thin as 10 nm. However, the source and drain series resistances increased with increasing of α-IGZO channel thickness, which results in the apparent field-effect mobility decreasing. The threshold voltage shift (Δ V th ) under negative bias stress (NBS) and negative bias illumination stress (NBIS) were investigated, also. The hump-effect in the sub threshold region under NBS and threshold voltage shift to negative position under NBIS were enhanced with decreasing of α-IGZO channel thickness, owing to the enhancement of vertical electrical field in channel.

In this letter, thin-film transistors (TFTs) were demonstrated with In2O3 channel layer prepared by metal–organic chemical vapor deposition (MOCVD). Treated by O2 microwave plasma on the In2O3 channel, high performance was obtained such as ultra-high field-effect mobility of 243 cm $^{\mathrm {\mathbf {2}}}$ /Vs, ON/OFF current ratio of $10^{\mathrm {\mathbf {7}}}$ , and high stability under negative bias illumination stress, although no typical electrical characteristics were observed for TFTs without O2 microwave plasma treatment. The effects of O2 microwave plasma treatment were investigated by Hall effect measurements, X-ray photoelectron spectroscopy, and Kelvin probe force microscopy. The results indicated that the O2 microwave plasma treatment leads to the oxygen ions adsorption onto the In2O3 surface and the consequent depletion of In2O3 channel. The MOCVD-grown In2O3 TFTs with ultra-high field-effect mobility are potentially applied in the next-generation system on panel.

Deck assembly is critical quality control point in final satellite assembly process, and cable extrusion and structure collision problems in assembly process will affect development quality and progress of satellite directly. Aimed at problems existing in deck assembly process, assembly project scheme for satellite deck based on robot flexibility control principle is proposed in this paper. Scheme is introduced firstly; secondly, key technologies on end force perception and flexible docking control in the scheme are studied; then, implementation process of assembly scheme for satellite deck is described in detail; finally, actual application case of assembly scheme is given. Result shows that compared with traditional assembly scheme, assembly scheme for satellite deck based on robot flexibility control principle has obvious advantages in work efficiency, reliability and universality aspects etc.

In this study, the high performance of InGaN/GaN multiple quantum well light-emitting diodes (LEDs) with Al-doped ZnO (AZO) transparent conductive layers (TCLs) has been demonstrated. The AZO-TCLs were fabricated on the n+-InGaN contact layer by metal organic chemical vapor deposition (MOCVD) using H2O as an oxidizer at temperatures as low as 400 °C without any post-deposition annealing. It shows a high transparency (98%), low resistivity (510−4 Ωcm), and an epitaxial-like excellent interface on p-GaN with an n+-InGaN contact layer. A forward voltage of 2.82 V @ 20 mA was obtained. Most importantly, the power efficiencies can be markedly improved by 53.8%@20 mA current injection and 39.6%@350 mA current injection compared with conventional LEDs with indium tin oxide TCL (LED-III), and by 28.8%@20 mA current injection and 4.92%@350 mA current injection compared with LEDs with AZO-TCL prepared by MOCVD using O2 as an oxidizer (LED-II), respectively. The results indicate that the AZO-TCL grown by MOCVD using H2O as an oxidizer is a promising TCL for a low-cost and high-efficiency GaN-based LED application.

Spacecraft Automatic Levelling and Equalizing Hoist Device (SALEHD) is a kind of hoisting device developed for eccentric spacecraft level-adjusting, based on hanging point adjustment by utilizing XY-workbench. To make the device automatically adjust the spacecraft to be levelling, the controller for SALEHD was designed in this paper. Through geometry and mechanics analysis for SALEHD and the spacecraft, the mathematical model of the controller is established. And then, the link of adaptive control and the link of variable structure control were added into the controller to adapt the unknown parameter and eliminate the interference of support vehicle. The stability of the controller was analysed, through constructing Lyapunov energy function. It was proved that the controller system is asymptotically stable, and converged to origin that is equilibrium point. So the controller can be applied in SALEHD availably and safely.

In this paper, we report the resistive switching characteristics of organic-inorgainc nanocomposite layer of LiFePO4 nano-particle (NP) embedded in conjugated polymer P3HT (P3HT:LiFePO4-NP). Memory devices with Al/P3HT/P3HT:LiFeP4-NP/ITO structure exhibit forming-free bipolar resistive switching behavior under bias voltage sweeping. Our devices achieved low set (1.2 V) and reset voltage (0.7 V), excellent data retention, high memory margin of more than 105 on/off resistance ratio and data endurance >100 times, indicating their great potential for memory application. The resistive switching mechanism was investigated by c-AFM measurement and temperature-current dependence results based on conductive filament model. It is deduced that the metallic filament was formed by diffusion and redox of Li+ ion under bias.