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Biomimetic mineralization of high-strength apatite structure essentially relies on mimicking the inorganic building blocks of naturally occurring bones. However, conventional routes still have substantial function gaps in providing precision control over the geometrical dimensions and crystalline morphology of biomineralized apatite. Herein, we conceived the concept of microwave-assisted biomineralization (MAB) to customize 1D hydroxyapatite nanowhiskers (HANWs) at graphene templates, rendering the formation of graphene-hydroxyapatite (Gr-HA) nanohybrids. The HANWs essentially resembled bone apatite in elemental composition (Ca/P = 1.74), diameter (~20 nm), crystallinity (63 %), and rodlike geometry (aspect ratio of ~6). The Gr-HA nanohybrids were uniformly incorporated into poly(lactic acid) (PLA) microfibers (~1 μm) by electrospinning, engendering fibrous membranes with a set of Gr-HA loadings (10, 20 and 30 wt%). Intimate interactions were generated between Gr-HA and PLA matrix, contributing to significant promotion of the mechanical properties for PLA composite membranes. For example, the yield strength and elastic modulus of the PLA composite membranes loaded with 30 wt% Gr-HA achieved 5.4 and 66.4 MPa, increasing nearly 182 % and over 94 % compared to those of pure PLA, respectively. Moreover, the bone-like HANWs endowed PLA membranes with excellent cytocompatibility and good bioactivity, as demonstrated by over 38 % increase in cell viability and rapid apatite formation in mineral solution. The impressive combination of mechanical properties and biological characteristics make the PLA/Gr-HA scaffolds promising for guided tissue/bone regeneration therapy.

The application of poly(lactic acid) (PLA) in the packaging area is frequently dwarfed by the inadequate gas/water barrier properties, low heat resistance and high UV transmittance. Herein, an environmentally friendly and high-efficiency microwave-assisted functionalization (MAF) approach was proposed to aqueous grafting waste bamboo fibers with the bridging agent. It permitted significant promotion of interfacial interactions between the MAF bamboo fibers (MAFBs) and neighboring PLA chains, contributing to uniform dispersion and intimate interphase. Featuring the morphological features, the MAFB-reinforced (5, 10 and 20 wt%) PLA biocomposites achieved an unexpected combination of high mechanical properties, exceptional resistance to heat deflection and UV irradiation, and excellent water barrier performance. Upon addition of only 5 wt% MAFBs, the tensile strength and toughness of PLA composite films were increased to 46.5 MPa and 0.6 MJ/m

Various fractures and holes in the natural rock mass affected the mechanical properties of the rock mass and the safety construction of engineering. In this study, we investigated the mechanical properties of a single fracture-hole rock specimen using particle flow code 2D (PFC2D) numerical simulation software and through laboratory tests. We analysed the failure behaviours and mechanical properties of the rock specimen with a single fracture-hole specimen under different fracture angles. The failure modes of single fractured rock samples with different fracture angles were revealed. The fracture propagation and stress evolution of the rock specimen with a single fracture-hole under different fracture angles were investigated. The experimental results shown that the peak strength, peak strain, elastic modulus, initial fracture stress, and damage stress of the single fracture-hole rock specimen with different fracture angles were significantly less than those of the intact rock specimen. Moreover, fracture hole defects accelerated the generation of fractures and promote the failure of the rock specimen. The failure modes were divided into Y, inverted Y, and V types. Before the rock specimen fractures, the stress concentration area was mainly distributed at both ends of the fracture. The stress concentration area at both ends of the fracture gradually decreased, and the stress concentration area near the hole gradually increased as the fracture angle increased. By experiments, the acoustic emission of the model had gone through three stages: initial, steady growth, and rapid decline. The size of the inclination angle affected the number of acoustic emission hits and the generation of acoustic emission signals. Failure behaviours of the rock specimen with a single fracture-hole were systematically investigated, which could promoted the development of fracture rock mechanics and improved the understanding of instability failure mechanism in rock engineering, such as nuclear wasted treatment engineering and deep underground engineering.

The past decades have witnessed the archetypal shift from petroleum-based to bioplastics including poly(lactic acid) (PLA) for multifunctional packaging. Here we disclose a microwave-assisted functionalization (MAF) approach to functionalize wood fibers (FWFs) at minute level and high yields (approaching 99 %), conferring high affinity to PLA matrix and significant promotion of mechanical properties. By incorporating of 10 wt% FWFs, the tensile strength and toughness of PLA composite films were elevated to 54.5 MPa and 1.6 MJ/m

Additional file 1.

Fractional order research has interdisciplinary characteristics and has been widely used in the field of natural sciences. Therefore, fractional order research has become an important area of concern for scholars. This paper used 2854 literatures collected from China National Knowledge Infrastructure (CNKI) database from 2001 to 2020 as the data source and used bibliometrics and two visualization methods to conduct bibliometric analysis and visualization research on China’s fractional order research. To begin with, this paper analyzed the time series distribution of publications, the distribution of research institutions, the author cooccurrence network, the distribution of important journals, and the distribution of important literature, which explained the research status of the fractional order. Furthermore, this paper used VOSviewer software to analyze the clustering and density distribution of the fractional order research keywords, which revealed the hotspots of the fractional order research. Finally, with the help of CiteSpace software, the burst keywords were analyzed to further explore the frontiers of fractional order research. This paper systematically reveals the research status, research hotspots, and research frontiers of China’s fractional order research, which can provide certain theoretical and practical references for related follow-up researchers.

Supplemental material, Supp_Material_cIMT_and_CSVD_cognitive_function20200623 for Carotid intima–media thickness relative to cognitive impairment in dialysis patients, and their relationship with brain volume and cerebral small vessel disease by Ke Zheng, Yujun Qian, Tiaye Lin, Fei Han, Hui You, Xixi Tao, Bo Hou, Jing Yuan, Haiyun Wang, Dingding Zhang, Ke Lv, Feng Feng, Yicheng Zhu and Xuemei Li in Therapeutic Advances in Chronic Disease

This paper studies the preparation and photocatalytic properties of graphene- ZnO nanorod composite with ultrasonic treatment. Graphene-ZnO nanorod composite photocatalyst with good structure is prepared after ultrasonic treatment for 30 h at 30 kHz in distilled water-ethanol dispersant using ultra-fine zinc powder. The effects of different proportions of zinc powder and expanded graphite on the photocatalytic properties of the composites are investigated. Besides, the prepared Graphene-ZnO nanorod composite photocatalyst is characterized by X-ray diffraction (XRD), laser Raman spectrometer (Ra-man), field emission scanning electron microscopy (SEM), transmission electron microscopy (TEM), and ultraviolet–visible spectroscopy (UV–Vis). It is found that ZnO nanorods in the composite exhibit a hexagonal wurtzite structure and are uniformly coated on the surface of graphene with a diameter of about 20 nm. The degradation efficiency of the composite materials prepared with different proportions of zinc powder and expanded graphite to methyl orange is quite different. When the zinc powder is 1.0 g, the photocatalytic activity of the composite is better than that with the same amount of zinc oxide nanorods. Results prove that the composite materials prepared with the appropriate proportion of raw materials show good photocatalytic performance, and the composite process is simple because it can be completed only under ultrasonic conditions. It breaks through the limitation of high temperature and high pressure in the traditional preparation process and has important reference significance for the development of zinc oxide composite in the field of catalysis.

The depth profile measured by secondary ion mass spectroscopy is influenced by factors such as the atomic mixing caused by ion injection, the crater edge, the crystallographic orientation of grains and the surface roughness etc., resulting in the deviation of the measured profile from the real distribution of the solute atoms. A depth profile measured before diffusion annealing or the zero profile is a comprehensive characterization of all the factors that influence the depth profile after annealing. In the present study, a mathematic method using Fourier serials to effectively deconvolute the real profile from the measured profile and zero profile is proposed. And the effects of zero profile on the diffusion properties of Zn in a coarse grained Cu and a nanostructured Cu produced by dynamic plastic deformation (DPD) at liquid nitrogen temperature (LNT) are analyzed with the

Lane Departure Warning System(LDWS) is a car safety assist systems,following the capsule of the safety,whose main task is to extract lane markings and make warning-decision.In this paper,the lane departure warning system hardware architecture is designed based on TMS320DM642 which acts as the central processing unit.The algorithms turn the image into grayscale,and then detect the image's edge information,in the end set the region of interest(ROI) on the image.Hough transform based on phase grouping is used to extract the lanes,and according to the lane departure warning conditions,the system analyzes whether the warning should be presented or not and gives the driver warning singles when it is unconscious.The experiments results proved that the system will make warning in 2.5 s before the traffic accident,which implements the aim of the real-time,reliable lane departure warning.

PurposeThe purpose of this paper is to study the inhibitive property of the mixture of an imidazole derivative (IMA) and benzotriazole (BTA) to the copper in deionised water.Design/methodology/approachStatic mass‐loss tests, electrochemical tests and surface analysis are used to study the inhibitive property of the mixture of an IMA and BTA to copper in deionised water.FindingsThere is a synergistic inhibitive effect on inhibition of the copper by the IMA and BTA in deionised water, and the mixture of the IMA and BTA is an effective inhibitor that mainly hinders the anode reaction.Practical implicationsThe mixture of the IMA and BTA is an effective inhibitor and can be used to prevent copper from corrosion in deionised water.Originality/valueThe mixture of the IMA and BTA is an effective inhibitor and should be suitable for use in the cooling water of an electricity generator unit to prevent corrosion of the copper conductors.

Status quo bias is an important factor which affects investors' decision-making. The existing research on this issue only considers Prospects Theory. In fact, framing effect, investor sentiment and information structure are also important variables which affect status quo bias. But the existing papers are less involved to study status quo bias from the three aspects above. This paper researches the impact on investors status quo bias from the three aspects of framing effect? investor sentiment and information structure in the experimental method. The results show that: The investor status quo bias in the margined frame of the investment portfolio is higher than that in the ratio frame of the investable portfolio. There is status quo bias of investors in the three emotions conditions. In the positive emotions investors status quo bias is lower and in the negative emotions investors status quo bias is higher. The amount of choose the determined probability is five times that choose uncertainty probability .The level of status quo bias in self-status assignment group is higher than that in external status assignment group.

In face recognition, the class mean of the training samples may deviate from the class center in small sample size. The method based on adaptively weighted fisherface is one of the approaches to deal with the problem. However, it didnpsilat consider the face recognition efficiency. To improve recognition efficiency, the paper proposes a highly-efficient face recognition method based on weighted LDA. Firstly, the wavelet transform is applied to the face image so that the lowest resolution sub-image of the face image is obtained. Secondly, the dimension of sub-image is reduced by 2DPCA. In the end, the class means are updated by using the weighted feature vector in the reduced order subspace. The traditional LDA is improved by using the new class means. The experiments on the ORL face database show that the proposed method can achieve higher recognition rate and efficiency as well as better implementation result.

Objective To evaluate the efficacy and safety of olmesartan (OLM) and olmesartan plus hydrochlorothiazide (fixed-dose combination of OLM/HCTZ 20 mg/12.5 mg) combined with amlodipine (AML) in Chinese patients with mild to moderate essential hypertension who had insufficient response for AML mono-therapy. Methods This was an open label, non-comparative, multicenter clinical trial. The patients who had not achieved targeted BP (defined as DBP 20 mmHg. Results In the intent-to-treat analysis (n = 409), the rate of the responders at the end of week 4, 8, 12, 16 was 76.3%, 86.3%, 95.4%, 97.1%, respectively. In terms of DM subjects (n = 54), the rate was 88.9% at the end of treatment. The mean changes of blood pressure from baseline in all subjects at week 4, 8, 12 and 16 were as below. Only one SAE (no drug related) was reported during the study period. Conclusions In Chinese hypertensive patients with insufficient response for AML mono-therapy, OLM and OLM plus HCTZ combined with AML are efficacious in lowering BP and have an acceptable safety and tolerability profile.

Propagation of solitons is investigated on an inhomogeneous plasmas that contain two kinds of ions with different masses.The nonlinear acoustic waves can be described by either KdV-type equation or Nonlinear Schrdinger equation in the lowest order.The amplitudes,propagating velocities or wave shapes of these quasi-solitons are analytically given in this paper.

Transmission and reflection of soliton in an inhomogeneous plasma are investigated, the transmission and reflection waves both can be described by the KdV equation in the lowest order. The numbers and magnitude of both transmitted and reflected solitons from an incident soliton are given analytically.