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Aims Investigate the involvement of 15-hydroxyeicosatetraenoic acid (15-HETE), an anti-inflammatory molecule, on the beneficial effects of exercise therapy for osteoarthritis (OA). Main methods 15-HETE (10 μM, twice a week) and monosodium iodoacetate (MIA) (1 mg) were injected into rat knee joints. Treadmill exercise was applied on OA rat. Primary rat chondrocytes were treated with 15-HETE, LY294002 and interleukin (IL)-1β. Rats undergo a 1 hour single session treadmill exercise once. 15-HETE levels in the knee joint were evaluated using ELISA after a single session of treadmill exercise on healthy and OA rats. Matrix metalloproteinase (MMP)3, MMP-13, a disintegrin and metalloproteinase with thrombospondin motif (ADAMTS)-5, p-Akt, Akt, and collagen type 2 (COL2) expression were evaluated using RT-PCR and western blotting. OA degree was evaluated using X-ray, scored by Osteoarthritis Research Society International (OARSI) and Mankin scores. COL2 and MMP-13 expression in articular was evaluated using immunohistochemistry. Key findings Medium intensity exercise alleviated OA. 15-HETE levels after exercise was increased. 15-HETE inhibited IL-1β-induced inflammation in primary chondrocytes and increased p-Akt levels. LY294002 blocked the effect of 15-HETE in vitro. Finally, 15-HETE alleviated cartilage damage, inhibited MMP-13 expression, and increased COL2 expression in joint cartilage tissue. Significance Treadmill exercise alleviates OA and increases 15-HETE levels in the knee joint, which suppresses inflammation in chondrocytes via PI3k-Akt signalling in vitro and in vivo.

Monolayer iron-oxide films are attractive for both spintronic application and surface chemical catalysis. However, the detailed atomic structure of the FeO monolayer which is crucial for understanding the physical and chemical properties of the films is not well understood. In this work, we fabricate high-quality monolayer FeO films on the Au(111) substrate by molecular-beam epitaxy. High-resolution scanning tunneling microscopy measurements simultaneously reveal the close-packed atomic arrangement and hexagonal moir\'e pattern of the monolayer FeO and were combined with hexagonal commensurate mode calculations to establish the atomic structure of the monolayer FeO(111) with respect to the Au(111) substrate. The identification of this stable commensurate arrangement of FeO(111) monolayer on Au(111) paves the way for the exploration of its fundamental science and its applications in industry.

Moiré superstructure–induced edge state modulation has been observed in bismuthene homojunctions., Creating and controlling the topological properties of two-dimensional topological insulators is essential for spintronic device applications. Here, we report the successful growth of bismuth homostructure consisting of monolayer bismuthene and single-layer black phosphorus–like Bi (BP-Bi) on the HOPG surface. Combining scanning tunneling microscopy/spectroscopy with noncontact atomic force microscopy, moiré superstructures with twist angles in the bismuth homostructure and the modulation of topological edge states of bismuthene were observed and studied. First-principles calculations reproduced the moiré superlattice and indicated that the structure fluctuation is ascribed to the stacking modes between bismuthene and BP-Bi, which induce spatially distributed interface interactions in the bismuth homostructure. The modulation of topological edge states is directly related to the variation of interlayer interactions. Our results suggest a promising pathway to tailor the topological states through interfacial interactions.

Atomic-scale defects in two-dimensional transition metal dichalcogenides (TMDs) often dominate their physical and chemical properties. Introducing defects in a controllable manner can tailor properties of TMDs. For example, chalcogen atom defects in TMDs were reported to trigger phase transition, induce ferromagnetism, and drive superconductivity. However, reported strategies to induce chalcogen atom defects including postgrowth annealing, laser irradiation, or plasma usually require high temperature (such as 500 °C) or cause unwanted structural damage. Here, we demonstrate low-temperature (60 °C) partial surface oxidation in 2D PdSe

Disorder-induced magnetoresistance (MR) effect is quadratic at low perpendicular magnetic fields and linear at high fields. This effect is technologically appealing, especially in the two-dimensional (2D) materials such as graphene, since it offers potential applications in magnetic sensors with nanoscale spatial resolution. However, it is a great challenge to realize a graphene magnetic sensor based on this effect because of the difficulty in controlling the spatial distribution of disorder and enhancing the MR sensitivity in the single-layer regime. Here, we report a room-temperature colossal MR of up to 5,000% at 9 T in terraced single-layer graphene. By laminating single-layer graphene on a terraced substrate, such as TiO2 terminated SrTiO3, we demonstrate a universal one order of magnitude enhancement in the MR compared to conventional single-layer graphene devices. Strikingly, a colossal MR of >1,000% was also achieved in the terraced graphene even at a high carrier density of ~1012 cm-2. Systematic studies of the MR of single-layer graphene on various oxide- and non-oxide-based terraced surfaces demonstrate that the terraced structure is the dominant factor driving the MR enhancement. Our results open a new route for tailoring the physical property of 2D materials by engineering the strain through a terraced substrate., 64 pages; Main 31 pages, 4 figures; Supplementary 33 pages, 18 figures

The research of two-dimensional (2D) systems mainly focuses on two kinds of materials: graphene-like materials and transition metal dichalcogenides (TMDs). Both of them host unconventional 2D electronic properties and have potential applications on nanodevices in future. During the past years, molecular beam epitaxy (MBE) has proven to be outstanding in the synthesis of 2D materials. In this chapter, we will summarize several kinds of 2D systems, including graphene-like materials and TMD materials, which have been successfully realized by MBE.

We report the successful preparation of a purely honeycomb, graphene-like borophene, by using an Al(1 1 1) surface as the substrate and molecular beam epitaxy (MBE) growth in ultrahigh vacuum. Scanning tunneling microscopy (STM) images reveal perfect monolayer borophene with planar, non-buckled honeycomb lattice similar as graphene. Theoretical calculations show that the honeycomb borophene on Al(1 1 1) is energetically stable. Remarkably, nearly one electron charge is transferred to each boron atom from the Al(1 1 1) substrate and stabilizes the honeycomb borophene structure, in contrast to the negligible charge transfer in case of borophene/Ag(1 1 1). The existence of honeycomb 2D allotrope is important to the basic understanding of boron chemistry, and it also provides an ideal platform for fabricating boron-based materials with intriguing electronic properties such as Dirac states.

Two-dimensional surface structures often host a surface state in the bulk gap, which plays a crucial role in the surface electron transport. The diversity of in-gap surface states extends the category of two-dimensional systems and gives us more choices in material applications. In this article, we investigated the surface states of β-√3 × √3-Bi/Si(111) surface by scanning tunneling microscopy. Two nearly free electron states in the bulk gap of silicon were found in the unoccupied states. Combined with first-principles calculations, these two states were verified to be the Bi-contributed surface states and electron-accumulation-induced quantum well states. Due to the spin-orbit coupling of Bi atoms, Bi-contributed surface states exhibit free-electron Rashba splitting. The in-gap surface states with spin splitting can possibly be used for spin polarized electronics applications.

In recent years, the overuse of antibiotics has caused more and more serious environmental pollution, the uncontrolled abuse of antibiotics makes bacteria produce resistance to antibiotics faster than the replacement rate of antibiotics themselves, leading to the emergence of super drug-resistant bacteria. Therefore, it is of great practical significance to establish a simple, rapid and sensitive method for the detection of antibiotics. By integrating natural nano-clay (Atta) and carbon dots (CDs), the real-time and rapid visual detection of tetracycline (TC) in the sample can be realized by chromaticity pick-up APP on smartphone. The nano-sensor can detect tetracycline in the concentration between 25 nM and 20 μM with the detection limit of 8.7 nM. The low detection limit coupled with good accuracy, sensitivity and specificity meets the requirements for the detection of tetracycline in food. More importantly, the test paper and fluorescent stick-like nano-sensor are designed to detect tetracycline by polychromatic fluorescence changes. In addition, a logic gate for semi-quantitative identification of the concentration of tetracycline is designed, which makes it possible for the application of the nano-sensor in the field of smart devices.

Five lanthanide-containing complexes, featured with the structural formula of [Ln4(L1)4(L)6(μ3-OH)2]·m(CH3CN) and a related binuclear Yb-based complex, were synthesized and structurally characterized (HL = 5-(2-furanimino)-8-hydroxylquinoline; HL1 represents for β-diketone ligand). The solid-state near-infrared fluorescence was also tested. Complex 3 emits characteristic near-infrared luminescence of the corresponding Er3+ ions when excited by ultraviolet spectrum of 350 nm, which demonstrates the efficient energy transfer from the excited triplet states of the ligands to the central Er3+ ions.

The effects of trace MoSi2 addition on the microstructure evolution, mechanical properties and fracture behavior of Ti–6Al–4V wall via cold metal transfer additive manufacturing (CMTAM) were investigated. After the addition of trace MoSi2 powder, trace (β-Ti, Mo) phase and SiO2 particles were obtained and partly prior-β→α’ phase transformation was suppressed. Compared with the as-built Ti–6Al–4V wall, the prior-β grains changed from columnar to the equiaxed or near-equiaxed after the addition of trace MoSi2. The tensile analysis result revealed that the addition of trace MoSi2 could improve the average strain while reduce anisotropy. All specimens showed dimples corresponding to ductile failure mode. The possible thermal cycles for the trace-MoSi2-addition specimens during the CMTAM process were analyzed.

The hydrogenation of two-dimensional (2D) systems can efficiently modify the physical and chemical properties of materials. Here we report a systematic study on the hydrogenation of 2D semiconductor Sn2Bi on Si(111) by scanning tunneling microscopy experiments and first principle calculations. The unique butterfly-like and trench-like features were observed for single H adsorption sites and hydrogen-saturated surfaces respectively, from which the bridge-site adsorption geometry can be unambiguously determined. The structural model was further confirmed by the theoretical calculations, which is in good agreement with the experimental observation. In addition, the hydrogenation is found to vanish the flat band of Sn2Bi and increase the band gap obviously.

Two-dimensional (2D) materials consisting of heavy atoms with particular arrangements may host exotic quantum properties. Here, we report a unique 2D semiconducting binary compound, a Sn_{2}Bi atomic layer on Si(111), in which hexagons are formed by bonding Bi with a triangular network of Sn. Because of the unique honeycomb configuration, the heavy elements, and the energy-dependent hybridization between Sn and Bi, 2D Sn_{2}Bi not only shows strong spin-orbit coupling effects but also exhibits high electron-hole asymmetry: Nearly free hole bands and dispersionless flat electron bands coexist in the same system. By tuning the Fermi level, it is possible to preserve both nearly free and strongly localized charge carriers in the same 2D material, which provides an ideal platform for the studies of strongly correlated phenomena and possible applications in nanodevices.

The algorithm has been improved to the adaptive genetic operators and flow based on the basic theory of simple genetic algorithm and adopted elitism strategy to select the best individual for iterative operation. The improved genetic algorithm not only ensured better global search performance, but also improved the convergent speed. The optimal solution was obtained and simulated by the improved genetic algorithms under the kinematical constraints.

Combining ultrahigh sensitivity, spatial resolution, and the capability to resolve chemical information, tip-enhanced Raman spectroscopy (TERS) is a powerful tool to study molecules or nanoscale objects. Here we show that TERS can also be a powerful tool in studying two-dimensional materials. We have achieved a ${10}^{9}$ Raman signal enhancement and a 0.5 nm spatial resolution using monolayer silicene on Ag(111) as a prototypical 2D material system. Because of the selective enhancement on Raman modes with vertical vibrational components in TERS, our experiment provides direct evidence of the origination of Raman modes in silicene. Furthermore, the ultrahigh sensitivity of TERS allows us to identify different vibrational properties of silicene phases, which differ only in the bucking direction of the Si-Si bonds. Local vibrational features from defects and domain boundaries in silicene can also be identified.

According to the principle of multi-body dynamics, using ADAMS module of ADAMS/CAR to form a complete vehicle model, and by using INSIGHT module used to design suspension hard point, the simulation analysis was carried out . Controllability and stability of the vehicle is to make evaluation and analysis by the experiments cornering with steer release. Ordinal optimization of before and after the optimization model , the results were analyzed, it demonstrated that optimized score significantly higher than before optimization.

We present the successful synthesis of single-atom-thick borophene nanoribbons (BNRs) by self-assembly of boron on Ag(110) surface. The scanning tunneling microscopy (STM) studies reveal high quality BNRs: all the ribbons are along the [-110] direction of Ag(110), and can run across the steps on the surface. The width of ribbons is distributed in a narrow range around 10.3 nm. High resolution STM images revealed four ordered surface structures in BNRs. Combined with DFT calculations, we found that all the four structures of boron nanoribbons consist of the boron chains with different width, separated by hexagonal hole arrays. The successful synthesis of BNRs enriches the low dimensional allotrope of boron and may promote further applications of borophene, Comment: 14 pages, 3 figures

Two-dimensional (2D) allotrope of tin with low buckled honeycomb structure, named as stanene, is proposed to be an ideal 2D topological insulator with a nontrivial gap larger than 0.1 eV. Theoretical works also pointed out the topological property of stanene occurs by strain tuning. In this letter, we report the successful realization of high quality, monolayer stanene film as well as monolayer stanene nanoribbons on Sb(111) surface by molecular beam epitaxy, providing an ideal platform to the study of stanene. More importantly, we observed a continuous evolution of the electronic bands of stanene across a nanoribbon, which are related to the strain field gradient in stanene. Our work experimentally confirmed that strain is an effective method for band engineering in stanene, which is important for fundamental research and application of stanene., Comment: 10 pages, 4 figures

The trajectory is planned with fifth-order uniform B-splines for the industrial robot aimed to assure the motion is smooth and the trajectory is fourth-order continuous. Under the premise to satisfy the initial kinematic parameters of the robot as zero, its speed, acceleration and jerk are continuous. Based on B-spline theory, process five B-spline curve function is calculated inversely in joint space. Under the robot kinematics parameter constraints, using fifth-order B-spline interpolates to plan robot trajectory when known interpolation points and the kinematic parameters are simulated and validated by the software of ADAMS.So it provides an effective new method for the trajectory planning.

The algorithm has been improved to the adaptive genetic operators and flow based on the basic theory of simple genetic algorithm and adopted elitism strategy to select the best individual for iterative operation. Program the operation process in the MATLAB software. The improved genetic algorithm not only ensured better global search performance, but also improved the convergent speed. The optimal solution was obtained by the improved genetic algorithms under the kinematical constraints.

Completed the design of experimental apparatus of magnetic levitation based on ADuC832 microcontroller and discussed the experimental results, the relationship between the forces on permanent magnet and the velocity of non-ferromagnetic conductor can be measured with strain gauge position sensor and photoelectric sensor. A magnet can be non-contact driven to rotate around its central axis by moving conductor, the relationship between the rotational speed of permanent magnet and the velocity of conductor can measured with bias circuit, verifying the correctness of the theoretical analysis. The experimental apparatus of magnetic levitation is well applied in experimental teaching.

In order to improve the riding and handling of the vehicle，the full-vehicle dynamical model of a certain vehicle is established by means of the software Adams/Car．The design of multi-objective optimization was used for Suspension system parameters on the base of the dynamical model．The optimized results show that riding of the vehicle is retained and dynamic load of wheel is improved obviously．It can be concluded that the optimization method is feasible for the optimization design of suspension system parameters．the investigation also supply the basis of theory for design considering the matching of the suspension system parameters.

With the continuous development of industrial robot application, it becomes very important for the solution of reachable space in the designing and applicating process. But the traditional theory calculation method is complex. When solving the reachable space of new kind of robot, we only draw lessons from the theory and need to change more. So a simple and convenient method is needed in theory field. This paper proposes a method that combine Matlab with SimDesigner to solve 6-DOF Robot reachable space, and takes ABB-1400 as an example to explain the solution of 6-DOF Robot reachable space. It could attain the full reachable space by add sine motion function reasonably to every joint, and obtain the solution of robot reachable space speedly.

The cutting vibration is a very harmful phenomenon, which destroys the surface finish and dimensional integrity of workpieces and quickens the wear of cutting tool. The cutting vibration can be suppressed or reduced by applying the variable spindle speed cutting. In order to investigate the effect of variable spindle speed parameters and cutting conditions on suppressing the vibration, the deeper slot milling tests have been conducted. The results have shown that the vibration occurring in deeper slot milling can be reduced by applying the method of variable spindle speed milling, as long as the variable speed parameters are elected suitably. The values of speed variation amplitude Δn/n0 and speed variation frequency fn of spindle speed trajectory parameter have a great effect on antivibration. Under this article test condition, the amplitude Δn/n0 of variable spindle speed is 20% and frequency fn of variable spindle speed is 0.3Hz.

Tip-enhanced Raman spectroscopy (TERS), which combines scanning probe microscopy with the Raman spectroscopy, is capable to access the local structure and chemical information simultaneously. However, the application of ambient TERS is limited by the unstable and poorly controllable experimental conditions. Here, we designed a high performance TERS system based on a low-temperature ultrahigh-vacuum scanning tunneling microscope (LT-UHV-STM) and combined with a molecular beam epitaxy (MBE) system. It can be used for growing two-dimensional (2D) materials and for in situ STM and TERS characterization. Using a 2D silicene sheet on the Ag(111) surface as a model system, we achieved an unprecedented 109 Raman single enhancement factor in combination with a TERS spatial resolution down to 0.5 nm. The results show that TERS combined with a MBE system can be a powerful tool to study low dimensional materials and surface science.

This paper describes the study on an innovative miniature 1×2 mechanical optical switch with anti-thermal design. Firstly, a novel switch configuration with line-to-line and fiber-to-fiber alignments is designed. An included anti-thermal mechanism is proposed by utilizing materials with different thermal expansion coefficients to compensate the axial misalignment due to ambient temperature changes. Then, parametric programs to automatically generate the solid model and to analyze thermal behavior of the switch are developed. Finally, a prototype is fabricated and the temperature cycling tests of Bellcore specifications are carried out. According to experimental measurements, it is found that the insertion loss of the prototype satisfies the requirements of Bellcore specifications. This 1×2 mechanical optical switch is small, thermally balanced and reliable.

Interleukin-1beta (IL-1beta), a proinflammatory cytokine, has been involved in various diseases of the central nervous system (CNS). Due to the diverse, "contradictory" effects of IL-1beta on neurons during insults to the brain, the mechanisms underlying these effects have not been elucidated. Calcium influx through the L-type Ca2+ channels (LCCs) is believed to play a critical role in the cascade of biochemical events leading to neuron death in these pathophysiological conditions. So far, the mechanism of the interaction of IL-1beta and LCCs in the initiation and progression of these diseases is unclear. In this study, we investigate systemically the effects of IL-1beta on the LCCs current, which are believed to be implicated in the cascade of biochemical events leading to neuron death in neuropathological conditions. Using patch clamp, we observe that IL-1beta treatment (10 ng/ml, 24 h) suppresses LCC currents by approximately 38%, which made up half of the whole-cell Ca2+ current determined by nifedipine. IL-1beta does not alter the characteristics of single LCC including current amplitude, open probability, and conductance, but decreases the number of the functioning channel by 40%. Moreover, immunoblot assay exhibits that IL-1beta reduces the expression of LCC proteins by 38 approximately 42% in both whole neuron and plasma membrane fraction, and demonstrates that IL-1beta downregulates the LCC activity via the reduction of LCC density. According to early research pretreatments longer than 12 h may play a crucial role in the neuroprotective effects of IL-1beta, our findings may establish an explanation for the protective effects of this interleukin on neurons in the late stage of injury, and could raise a new issue to clinical treatment for insults to brain.

The planning skill training of the real estate development project in colleges and universities is an important means for the students majored with the real estate operation and valuation to master it. According to the in-depth researches of the real estate developers and many years’ teaching experience, we put forward the design idea of the skill training system. This idea contains three steps: design of training content, design of training mode and design of training system. This idea is helpful for building a sound training system, and is also helpful for the students to effectively carry out skill training, successfully achieve the goal of mastering the vocational skills, and increase the competitiveness of employment after graduation, thus playing a very good reference role in the development of other vocational skill training systems in colleges and universities

Blumea megacephala essential oil, obtained through steam distillation of samples collected from the Shiwang Mountains in Guangxi Province, China, was analyzed using GC-FID and GC-MS. Among the 65 compounds identified in the oil, the main compounds were borneol (13.6 %), β-caryophyllene (9.56 %), germacrene D (9.09 %), sabinene (6.37 %), and α-humulene (4.78 %). Antimicrobial activity revealed that the essential oil (1000 μg/disc) has promising antimicrobial effects against several pathogens, giving satisfactory inhibition zone diameter values (21.5, 21.6, 23.4, 23.8, 21.9) and MIC values (125, 125, 62.5, 125, 125 μg/ml) against Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli), Gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus), and yeast (Hansenula anomala). Antioxidant and antimicrobial activities were correlated with chemical composition., EXCLI Journal ; Vol. 10, 2011

To study the phenotypic and genotypic resistance to Fluoroquinolones in Neisseria gonorrhoeae (NG) isolated in Jiangsu province of China.In-vitro, susceptibility testing of ciprofloxacin and levofloxacin against ninety-five clinical isolates were determined by agar dilution method. Detection of mutation in the gyrA and parC genes was performed by polymerase chain reaction (PCR) assay and sequence analysis.The clinical isolates demonstrated 100% resistance to ciprofloxacin. Based on gyrA and parC mutations, 18 types could be categorized among the 54 isolates. Based on the same gyrA mutations,isolates with high MIC appeared to have had more mutations in parC gene.The status of resistance to ciprofloxacin in NG was quite serious, and ciprofloxacin treatment for the treatment of NG infections in Jiangsu province should not be recommended. The results from this study suggested that mutations in the parC gene had contributed to the development of high Fluoroquinolone resistance in NG.

To investigate the diagnostic criteria and therapeutic method of the Klippel-Trenaunay syndrome.Among 5 cases, there were 2 males and 3 females aged from 11 days to 73 years. Vasography was carried out in all five patients and MRA was performed in one patients.After operation, the symptoms improved in 4 cases: the portine-like erythemas on their limbs got unclear; the focuses diminished obviously; the circumferences of the suffered limbs shrank and the ulcer healed. For following-up period was not long enough, the long term therapeatic result was still uncertain.Once the diagnosis of the Klippel-Trenaunay syndrome was made, operation should be performed as early as possible. If the surgical time is selected in prepuberty, optimal result can be expected.

Based on the analysis of evolutionary characteristics of public opinion in social networking services (SNS), in the paper we propose a dynamic evolution model, in which opinions are coupled with topology. This model shows the clustering phenomenon of opinions in dynamic network evolution. The simulation results show that the model can fit the data from a social network site. The dynamic evolution of networks accelerates the opinion, separation and aggregation. The scale and the number of clusters are influenced by confidence limit and rewiring probability. Dynamic changes of the topology reduce the number of isolated nodes, while the increased confidence limit allows nodes to communicate more sufficiently. The two effects make the distribution of opinion more neutral. The dynamic evolution of networks generates central clusters with high connectivity and high betweenness, which make it difficult to control public opinions in SNS.

Fibronectin (FN) levels were determined in 64 cases with chronic renal failure (CRF), some of whom were undergoing dialysis. FN levels were 14.9 +/- 7.6 mg/dl in CRF (n = 20), 13.4 +/- 4.3 mg/dl in patients on continuous ambulatory peritoneal dialysis (CAPD) (n = 20) and 16.7 +/- 7.2 mg/dl in patients on hemodialysis (HD) (n = 24). All the levels were significantly lower than in normal subjects (23.1 +/- 4.6 mg/dl). Serum FN was compared with some nutritional indices. Positive correlations were found between serum FN and nitrogen balance (BN), serum prealbumin (PreA) and transferrin (Tf) in all the patients. With serum albumin (Alb), however, this correlation was only found in patients undergoing dialysis. Negative correlations were found between serum FN and the ratio of serum urea to serum creatinine (Surea/Scr) in CAPD and HD patients. In 10 CAPD patients, the low serum FN levels went up after increased protein intake. This indicates that it was the result of malnutrition due to decreased protein intake. Serum FN level reflects a negative BN earlier and better than serum PreA, Tf and Alb. It is a sensitive, reliable and simple index for judging the nutritional protein status and the effect of nutritional treatment in patients with CRF undergoing dialysis.