Night shift workers with disordered rhythmic mechanical loading are more prone to intervertebral disc degeneration (IDD). Our results showed that circadian rhythm (CR) was dampened in degenerated and ...aged NP cells. Long-term environmental CR disruption promoted IDD in rats. Excessive mechanical strain disrupted the CR and inhibited the expression of core clock proteins. The inhibitory effect of mechanical loading on the expression of extracellular matrix genes could be reversed by BMAL1 overexpression in NP cells. The Rho/ROCK pathway was demonstrated to mediate the effect of mechanical stimulation on CR. Prolonged mechanical loading for 12 months affected intrinsic CR genes and induced IDD in a model of upright posture in a normal environment. Unexpectedly, mechanical loading further accelerated the IDD in an Light-Dark (LD) cycle-disrupted environment. These results indicated that intrinsic CR disruption might be a mechanism involved in overloading-induced IDD and a potential drug target for night shift workers.
•Superalloy K648 was manufactured by extreme high-speed laser metal deposition.•The microstructure features were revealed for K648 superalloy made by EHLMD.•The yield and ultimate strengths were ...tested for K648 superalloy made by EHLMD.
Nickel-based superalloys have been widely used in manufacturing turbine blades, vanes, and discs of aircrafts and power generators that serve in challenging environment. In order to meet the requirements for rapid manufacturing of these large-scale and high-performance components, the extreme high-speed laser metal deposition (EHLMD) technology have attracted great attention in recent years. The EHLMD technology can significantly improve the efficiency compared with conventional laser metal deposition (LMD). Meanwhile, the solidification condition and the resultant microstructures and mechanical properties can also be dramatically changed. In this study, a high chromium superalloy (K648) has been additively manufacturing by using EHLMD for the first time. The key process parameters and the resulted microstructure and mechanical properties are investigated. The results have shown that the most important factors affecting the height, width, and depth of the single-track deposit of EHLMD K648 superalloy are powder feeding rate, laser power, and scanning speed, respectively. The height and the width of the deposits are the largest when the laser power, scanning speed, and the powder feeding rate are 1400 W, 25 m/min, and 30 g/min. There exist some incomplete fusions in the interlayer region and some pores in the interior region of the multi-track-multi-layer deposits. Columnar grains grow in the build direction within each layer, while equiaxed grains tend to form in the interlayer region. The average value of microhardness of EHLMD K648 superalloy is about 298.1 HV. The ultimate strength of EHLMD K648 superalloy is slightly lower than that of the forging GH648 superalloy but higher than that of the conventional LMD K648 superalloy.
Quantum key distribution (QKD) networks are promising to serve large numbers of users with information-theoretic secure communication. In QKD networks, the detection-safe protocol, termed ...measurement-device-independent (MDI) QKD, can naturally enhance realistic security by supporting untrusted measurement nodes. However, the environmental disturbances to quantum states degrade the performance of multi-user communication. Here we propose an MDI-QKD networking scheme with robustness against environmental disturbance and adaptability to multi-user access, where more than two users can generate keys simultaneously regardless of aligning reference frames and compensating channel disturbance on polarization. To achieve this, we introduce the reference-frame-independent protocol as well as a polarization-compensation-free method, design a multi-user measurement unit, and combine it with original two-user units. The scheme is experimentally demonstrated for the improvement of network robustness and adaptability in multi-user scenarios, and the time and device costs of disturbance compensation can be saved from
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The modulation of intrinsic properties, including magnetism in two-dimensional materials, has attracted considerable interest as it expands device performance and allows for advanced flexible ...electronics. Herein, a facile way is developed to modulate the magnetic and electrical response of graphdiyne (GDY) by precise nitrogen doping. The introduced nitrogen exists only in the form of specific pyridine nitrogen and can meet the relative change of 1:2:3 between different materials, which can be used as a switch-like property to manipulate charge transfer and spin. Among these, triazine-graphdiyne (TA-GDY) with the most nitrogen content achieves the highest saturation magnetization of up to 3.0 emu/g at 2 K. The accompanying moderate band gap and mobility of up to 7.56 cm2·V–1·s–1 endow it a broad application prospect. These results revealed that controllable nitrogen doping can modulate the physical properties of carbon-based materials, thus providing a critical way to extend their application in future carbon electronics involving spin.
Cystic fibrosis transmembrane conductance regulator (CFTR) plays important roles in arterial functions and the fate of cells. To further understand its function in vascular remodeling, we examined ...whether CFTR directly regulates platelet-derived growth factor-BB (PDGF-BB)-stimulated vascular smooth muscle cells (VSMCs) proliferation and migration, as well as the balloon injury-induced neointimal formation. The CFTR adenoviral gene delivery was used to evaluate the effects of CFTR on neointimal formation in a rat model of carotid artery balloon injury. The roles of CFTR in PDGF-BB-stimulated VSMC proliferation and migration were detected by mitochondrial tetrazolium assay, wound healing assay, transwell chamber method, western blot, and qPCR. We found that CFTR expression was declined in injured rat carotid arteries, while adenoviral overexpression of CFTR in vivo attenuated neointimal formation in carotid arteries. CFTR overexpression inhibited PDGF-BB-induced VSMC proliferation and migration, whereas CFTR silencing caused the opposite results. Mechanistically, CFTR suppressed the phosphorylation of PDGF receptor β, serum and glucocorticoid-inducible kinase 1, JNK, p38 and ERK induced by PDGF-BB, and the increased mRNA expression of matrix metalloproteinase-9 and MMP2 induced by PDGF-BB. In conclusion, our results indicated that CFTR may attenuate neointimal formation by suppressing PDGF-BB-induced activation of serum and glucocorticoid-inducible kinase 1 and the JNK/p38/ERK signaling pathway.
Hot cracking is a severe defect that occurs during the repair or manufacturing of directionally solidified superalloy by laser metal deposition. Understanding the cracking behavior and mechanism is ...vital to avoid these defects. In this study, a directionally solidified superalloy, IC10, was investigated by laser re-melting. Hot cracking not only occurred at high angle grain boundaries, but also the low angle grain boundaries. A critical angle, below which the hot cracking may not occur, exists within the scope of low angle grain boundaries. Hot cracking can be ascribed to the coupled effects of a liquid film, stress concentration, and particles enriched with Cr and Mo. The formation of liquid film can be ascribed to the liquation of low melting point structures. The stress concentration around the grain boundaries provides the driving force for crack initiation and propagation. The liquid feeding can be inhibited by particles enriched with Cr and Mo, which promote the initiation of cracks. These findings provide technical support for achieving successful repair and additive manufacturing strategy of the non-weldable directionally solidified superalloys.
•Hot cracking is the coupled effects of a liquid film, stress concentration and particles enriched with Cr and Mo.•Misorientation angle of dendrites affects the grain boundary energy, which decides the stability of liquid film.•The strain localization factor at liquid film of substrate is larger than that of re-melted zone.•Particles enriched with Cr and Mo can promote the hot cracking by inhibiting the liquid feeding.•The appropriate laser power and scanning speed are about 400 W and 8 mm/s, respectively.
It is always a difficult task to assign the peaks recorded from a vibrational spectrum. Herein, we explored a new pathway of density functional theory (DFT) simulation to present three kinds of ...spectra of ice XIV that can be referenced as inelastic neutron scattering (INS), infrared (IR), and Raman experimental spectrum. The INS spectrum is proportional to the phonon density of states (PDOS) while the photon scattering signals reflect the normal vibration frequencies near the Brillouin zone (BZ) center. Based on good agreements with the experimental data, we identified the relative frequency and made scientific assignments through normal vibration modes analysis. The two hydrogen bond (H-bond) peaks among the ice phases from INS were discussed and the dynamic process of the H-bond vibrations was found to be classified into two basic modes. We deduced that two H-bond modes are a general rule among the ice family and more studies are ongoing to investigate this subject.
The invention of electric vehicle can make great contribution to the transition to low-carbon city, because of its lower pollution feature. Electric vehicle has become a popular development trend in ...the automotive industry. This industry has a high degree of technological dependence. Electric vehicle technologies involve multiple disciplines, and study of the technology convergence among various disciplines can explain the interdisciplinary development in this field. Previous studies lack detailed estimation of promising and potential technology convergence relations as well as the detailed topics in this field. This paper combined qualitative and quantitative methods (e.g., network analysis, link prediction and text mining) and proposed a novel framework to explore promising and potential technology convergence relationships and topics in the field. The results are:(1) Eight promising relationships were found. For instance, the convergence relationship B60K–B60L is a promising example related to the convergence of “dashboards or the mounting of one or more propulsion units and related devices” and “the propulsion, operation monitoring or electric safety in electric vehicles”. (2) The topics of the five most promising ones are mainly about battery arrangement and protection, control systems, framework design, and charging connectors. Battery arrangement and protection are the most noteworthy promising topics. (3) Five potential convergence relationships are detected. For example, the convergence of “propulsion, operation monitoring or electric safety in electric vehicles” and “image data processing or generation” might occur in future innovation. (4) The potential topics might be electric vehicle condition display, compressor or pump electric control. The results could offer a reference to scientists, policy-makers and investors in the electric vehicle field, and the novel framework proposed in this paper could be applied to other technology fields to estimate the trends of technology convergence.
•The technology convergence in electric vehicle domain is studied.•The promising technology convergence relationships and topics are explored.•The potential technology convergence relationships and topics are estimated.•Battery arrangement and protection is the most noteworthy promising topics.•A new framework combining network, link prediction and text mining are proposed.
The inhibitory effects of essential oils (EOs) derived from coriander, lavender, geranium, thyme, savoury and eucalyptus were assessed against Sclerotinia sclerotiorum, the causal agent of carrot ...white mould. All EOs showed antifungal activity against the pathogen in vitro and in vivo. In addition, all EOs markedly increased 6‐methoxymellein in the treated carrots. The EOs of thyme and savoury were found to be more effective than other tested EOs. The enzymatic tests showed that thyme and savoury EOs were more able than lavender EO to significantly increase the level of chitinases, peroxidases, β‐1,3‐glucanases, polyphenol oxidase, peroxidase and phenylalanine ammonia‐lyase in the treated carrots, indicating that the EOs of thyme and savoury have potential to be considered as effective inducers of resistance against carrot white mould. In this study, all EOs inhibited myceliogenic and carpogenic germination of sclerotia at concentrations 1 and 10 µl/ml sterile distilled water, respectively. After gas chromatography/mass spectrometry, major component in the thyme EO was found to be thymol (39.15%) followed by p‐cymene (13.85%) and carvacrol (10.36%), while in savoury EO were carvacrol (41.9%), γ‐terpinene (17.38) and p‐cymene (11.25%).
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