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Previous studies have proved that arbuscular mycorrhizal fungi infection and phosphate transporters are particularly important for phosphorus uptake by plants. Early laboratory studies found that LbPT7 played a role in Pi uptake and it was affected by arbuscular mycorrhizal fungi. In order to verify the phosphorus uptake function of LbPT7 gene and the effect of interaction with arbuscular mycorrhiza on plants, we constructed LbPT7 overexpression vector with Nicotiana tabacum and obtained T1 generation overexpression positive plants as test material. Under the condition of pot experiment, we designed three factors: Arbuscular Mycorrhizal Fungi treatment, genotype treatment, phosphorus concentration treatment. After 4 weeks of treatment, we measured the biomass and phosphorus content of tobacco, and determined the colonization. The results showed that overexpression of LbPT7 can promote plant phosphorus uptake and inoculation of AM fungi further promote plant phosphorus uptake in phosphorus deficiency condition, but this effect of them can't superpose in phosphorus adequate conditions. Overexpression of LbPT7 promoted the absorption of phosphorus, but impeded the utilization of phosphorus of N. tabacum in phosphorus deficiency condition. Overexpression of LbPT7 had little effect on the colonization of AM fungi in N. tabacum. [ABSTRACT FROM AUTHOR]

Multi-underreamed anchors (MUAs) are widely used in areas with soft soils owing to their high ultimate capacity. To explore the bearing mechanism of MUAs in soft soil, this paper performs a model test of MUAs in silty clay and draws the following conclusions. With an increase in the underream number of MUAs, the ultimate capacity of the anchors significantly increases. The strength of MUAs develops faster and more efficiently than that of non-underreamed anchors but is lost faster after the load reaches its peak value. There are two failure modes of MUAs, namely arch-shaped and cylindrical failure modes. Both of them involve three processes: initial cracking, crack deflection, and crack penetration. The ultimate capacity of ground anchors is composed of end and side bearing capacity. For MUAs, both the side and end resistance effects are improved. Owing to the superposition of the two kinds of effects, the ultimate capacity of MUAs is higher than that of non-underreamed anchors. [ABSTRACT FROM AUTHOR]

An effective numerical analysis process was carried out to simulate an impact event based on the Hashin failure criterion and the Camanho degradation rule. The middle and shoulder of a cylinder were impacted by the edge of square-shaped impactors, and the remaining burst pressure was predicted. The accuracy of the numerical analysis was verified by results of two experiments that proved that the numerical analysis was reliable. The impact damage at different impact energies (20-200 J) was evaluated. According to the analysis carried out, the impact damage of gas cylinders intensified with increasing impact energy, and there existed a critical value of this energy. The damaged area of gas cylinders under the same impact energy first decreases and then increases from the inner to outer layer, and the maximum increase in the residual bursting pressure could reach 9.6%. [ABSTRACT FROM AUTHOR]

The fluorescence-enhanced probe was synthesized based on 4-aminoantipyrine and 2-hydroxy-1-naphthalaldehyde. The structure was characterized by NMR, ESI-MS, IR and X-ray single-crystal diffraction. The fluorescent probe HL1 synthesized in this thesis have recognition performance for Hg2+ and Ag+ in acetonitrile solution, with HL1 allowing visual detection of Hg2+. Their recognition properties and mechanisms were examined and investigated using fluorescence spectroscopy and ESI-MS. The binding ratios between the probe and the response ions were 1:1, while the detection limits for the response ions both reached 10–8 M and below, with the potential to detect actual samples. [ABSTRACT FROM AUTHOR]

Enhanced oxygen vacancy (VO) has been designated as an effective strategy to prepare high-performance MnO2 nanocatalysts for the oxidation of volatile organic compounds (VOC) for thereof unbalanced electronic structure, and rapid electron transfer which may even reduce the reaction temperature down to room temperature. Herein, the effects of the VO on the catalytic performance of nano-sized MnO2 were discussed by classifying the VO into surface-anchored and bulk-involved ones. Currently used introducing and modulating methods for VO including elemental doping, energetic particle bombardment, atmosphere heat treatment, mechanical chemistry, and redox methods are detailly reviewed. Corresponding regulating mechanisms for VO are expounded. Commonly used characterization methods including ESR, XPS, HRTEM, and UV-vis are reviewed. Furtherly, the unveiled question which is highly expected to be answered on VO of MnO2 nanocatalysts is proposed. The purpose of this review is to present the current status of research on MnO2 nanoparticles and to provide researchers with basic research ideas. [ABSTRACT FROM AUTHOR]

The severe cadmium (Cd) pollution of soil adversely affects food safety and human health. To prevent phytotoxicity and Cd accumulation in agricultural products, effective steps must be taken immediately. In the study, we added different concentrations (10, 50, and 250 mg/kg) of α-Fe2O3 nanoparticles (NPs) into Cd-contaminated soil, investigating the effects of α-Fe2O3 NPs on Cd toxicity. The various physiological indicators, such as antioxidant system, the distribution of Cd and the content of active ingredients in different parts of muskmelon were detected. The results revealed that α-Fe2O3 NPs greatly reduce Cd transport in plants and minimize Cd toxicity. Specifically, 250 mg/kg α-Fe2O3 NPs treatment reduced the root Cd content by 30.19% and 50 mg/kg α-Fe2O3 NPs treatment reduced the stem Cd content by 38.75%. For the content of active ingredients, 50 mg/kg α-Fe2O3 NPs treatment increased root polysaccharide content and leaf saponin content by 14.45 and 27.71%, respectively. Overall, α-Fe2O3 NPs can reduce Cd stress in muskmelon. The current work gave a unique notion for Cd remediation in soil using α-Fe2O3 NPs as amendments. [ABSTRACT FROM AUTHOR]

The fuel tank of the advanced heavy launch vehicle is made of 2219 aluminum alloy with a thickness of 18 mm. Friction stir welding (FSW) technology is used to achieve the welding of the fuel tank. The increase of thickness directly affects welding temperature field, which ultimately affects the welding quality. At present, the temperature distribution law of FSW thick 2219 aluminum alloy is still blank, which is a bottleneck to ensure high welding quality. In this paper, a temperature field measurement and analyses system based on K-type thermocouple and LabVIEW for friction stir welding is developed first. Then experiments are carried out and the temperature data in welding and thickness directions are measured and the temperature law is analyzed. The comparison of temperature distribution of FSW thick and thin 2219 aluminum alloy is made, and the influence of welding thickness on the temperature field is studied. Based on temperature field, weld strength and microstructure, the influence of different process parameters on welding quality is explored. The research results lay a foundation for optimization of the welding process parameters and realization of constant temperature control of FSW. [ABSTRACT FROM AUTHOR]

The severe electric and thermal environments may cause localized deterioration of the contact behavior of thermoelectric devices. The contact responses of the thermoelectricity under the joint effect of the finite size and the friction are analyzed. The law of the Coulomb friction is adopted. The obtained Fredholm kernel functions reveal the influence of the thickness and the friction. The known Jacobi polynomials are employed to discretize the obtained singular integral equation. The effects of the thermoelectric loadings (the total electric current and the total energy flux), friction coefficient, the thermoelectric strip thickness, and the elastic and thermoelectric material constants on the distribution of the normal traction and the surface in-plane stress are demonstrated in detail. The smaller thermal expansion coefficient and shear modulus will contribute to the lower stress concentration at both contact edges. The surface in-plane tensile stress behind the trailing edge can be alleviated as the thermoelectric strip becomes thinner. [ABSTRACT FROM AUTHOR]

In the current research, the influence of filling on the failure mechanism of nonpersistent joints under applied shear stress has been scrutinized using particle flow code (PFC2D). Additionally, the effects of nonpersistent joints on tunnel stability in jointed samples have been investigated. First, to reproduce the concrete specimen, PF2D was calibrated. The modeled samples with dimensions of 100×100 mm were numerically solved. The notch lengths were 15, 10, and 5 mm. The circular filling was situated in the middle part of the model, and the filling diameter was 30 mm. Gypsum materials have been employed to study the filling of modeled samples. The flat joint model was used for calibration. The tensile strengths of the concrete and gypsum samples were 3.4 and 1.4 MPa, respectively. Finally, shear tests were carried out on nine models. A shear load of 0.001 mm/sec was applied until the model's failure occurred. The results indicated that for fixed notch lengths and under normal loading conditions, shear cracks were induced in the filling layer. The tensile cracks were initiated from the original crack (joint) tips and extended within the model until coalescence with other joints and extended toward the model's boundaries. The maximum shear displacements accompanied by the shear strengths of the models increased with decreasing joint filling for the fixed notch lengths. [ABSTRACT FROM AUTHOR]

Background: Residual stress often generates during preparation, processing and use of silicon carbide (SiC) single crystal, which seriously affects the quality and service life of materials. Objective: This work aimed at evaluating the stress states in 6H-SiC single crystal wafers with different crystallographic orientations. Methods: The principle of determining the stress state of the hexagonal crystal system material through a multiple regression method was derived by modifying the related theory. Then the in-plane residual stress states of 6H-SiC samples grown along the [0001], 10 1 ¯ 0 and 11 2 ¯ 0 orientations were calculated, respectively. And the effect of the number of diffraction planes on the stress measurement results was studied. Finally, the stress results of SiC-6H materials grown in different crystallographic orientations were compared. Results: We found that the plane stress errors were gradually decreased with increase of the number of crystallographic planes, and were much lower than the ones estimated when the stress-free interplanar spacing was known; The residual stress states in single-crystal 6H-SiC of different crystallographic orientations were significantly different. Single-crystal 6H-SiC with 11 2 ¯ 0 growth direction had the smallest stress values, which was associated with the primary slip system {0001} ⟨ 11 2 ¯ 0 ⟩ . Conclusions: The improved methodology based on the multiple regression analysis can be applied to the stress measurement of single-crystal 6H-SiC. At least 6 planes should be used for stress detection to ensure the accuracy of residual stress results. Crystallographic orientation significantly influences the in-plane residual stress state in silicon carbide single crystal. [ABSTRACT FROM AUTHOR]

A triamine aryl pyrazole-based NIR fluorescent probe with good water solubility has been developed for detecting and imaging Aβ aggregates in Alzheimer's disease. In vitro studies have demonstrated that the probe high affinity to Aβ aggregates with an increase of fluorescence intensity have been due to the intramolecular charge transfer effect. The probes can specifically image Aβ plaques in brain sections of triple transgenic AD mice. [ABSTRACT FROM AUTHOR]

Objective: To identify the key genes and pathways involved in the occurrence and development of gastric cancer (GC). Methods: Differentially expressed genes (DEGs) and differentially expressed miRNAs (DEMs) were obtained using GEO2R. Function and pathway enrichment analysis of DEGs were performed using DAVID database.Protein-protein interaction (PPI) network analysis of DEGs was established by STRING database and visualized by Cytoscape software. Module analysis and hub genes selection of the PPI network was performed using Molecular Complex Detection (MCODE) and cytoHubba plug-in of Cytoscape software, respectively. Overall survival analysis of hub genes was performed by the Kaplan-Meier plotter online tool. Results: Totally, 98 DEGs were picked out, of which, 31 up-regulated genes were mainly involved in extracellular matrix (ECM)-receptor interaction, PI3K-Akt signaling pathway and focal adhesion, while 67 down-regulated DEGs were enriched in gastric acid secretion, collecting duct acid secretion and glycolysis/gluconeogenesis. Top 3 modules and top 10 hub genes with high centrality degree were selected from PPI network. Among these hub genes, high expression of secreted phosphoprotein 1 (SPP1), fibronectin1 (FN1) and collagen type I alpha 1 chain (COL1A1) were significantly associated worse overall survival for gastric cancer patients. Conclusions: The present study identified several key genes and pathways which may play an important role in the initiation and development of gastric cancer and could provide us potential targets for gastric cancer diagnosis and prognostic prediction. [ABSTRACT FROM AUTHOR]

The addition of Ca2MgSi2O7 to CaSiO3 bioceramics was investigated in order to modify the dissolution rate of CaSiO3. A series of CaSiO3–xCa2MgSi2O7 composite ceramics with x values of 2, 5, 10, and 20 wt% have been successfully obtained. The effects of Ca2MgSi2O7 addition on CaSiO3–Ca2MgSi2O7 ceramics degradation behavior and apatite formation were comprehensively investigated by means of X-ray diffraction (XRD), scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), Fourier transform infrared spectroscopy (FTIR), and inductively coupled plasma optical emission spectrometry (ICP-OES). The results showed that the dissolution rate of the achieve system ceramics gradually decreased in succession, and the apatite-forming was delayed by the addition of Ca2MgSi2O7. The suitable dissolution rate and apatite-forming ability of CaSiO3–Ca2MgSi2O7 bioceramics can be expected, indicating that the addition of Ca2MgSi2O7 to CaSiO3 bioceramics may be a promising route for modifying the dissolution behavior and apatite-forming ability of CaSiO3 bioceramics. [ABSTRACT FROM AUTHOR]

Eu3+/Tb3+-co-doped CaWO4 phosphors were synthesized by a simple green co-precipitation process. The structure of the samples was investigated by X-ray diffraction. The photoluminescence spectra and fluorescence decay lifetimes of the samples were measured to investigate the luminescence properties. We analyzed the energy transfer process between Eu3+- and Tb3+-doped CaWO4. As the Tb3+ to Eu3+ energy transfer process was confirmed, Eu3+- and Tb3+-co-doped CaWO4 phosphors showed a color-tunable emission from green to red under a 365-nm UV lamp. [ABSTRACT FROM AUTHOR]

Set-based association analysis has emerged as a popular tool for testing the association of rare variants within a genomic region with complex diseases. However, when only a small proportion of variants are causal, combining the association signals of multiple markers within a genomic region may cause noise due to the inclusion of non-causal variants, which usually decreases the power of a test. Besides, the existing set-based methods are sensitive to the genetic architecture. Therefore, we extend the aggregated Cauchy association test (ACAT) and propose an adaptive Cauchy-variable combination method (AAC). The AAC method adaptively combines Cauchy-variables transformed from variant-level P-values by using the optimal number of P-values that is determined by the data; the AAC method can remove variants with larger P-values. Extensive simulation studies and Genetic Analysis Workshop 19 real data analysis show that AAC is more powerful than the other comparative methods when only a small proportion of variants are causal. And AAC is robust to the varied genetic architecture. In addition, the AAC method may use summary statistics, without requiring the original genotypic and phenotypic data. [ABSTRACT FROM AUTHOR]

Based on the design and preparation of the electrically assisted drawing die, the electric-assisted deep-drawn tests were carried out on high-strength steel plates with different strengths to study the electroplastic effect on high-strength steel drawing. The temperature distribution, macro-morphology, and hardness variation of deep-drawing workpieces undergone different electrical parameters were analyzed. The results showed that the Joule heat generated by the electrically assisted drawing die on the sample was symmetrically distributed along the center of the circular sheet, and the electrical pulse heat effect had little effect on the temperature rise of sheets (same material) with different strength levels. The introduction of pulse current could improve the forming performance of high-strength steel to a certain extent, as well as enhance its deep-drawing deformation ability. The hardness of the work-piece increased after it was deep-drawn. The Joule heat generated by the pulse current did not cause changes in the microstructure of the high-strength steel. The electroplastic effect improved the mechanical properties of the work-piece while increasing the formability of the high-strength steel plates. [ABSTRACT FROM AUTHOR]

A new multi-branched model Cu(II) complex based on curcumin, namely CuL2(I) (НL = (1E,4Z,6E)-1,7-bis(4-(4-bromobutoxy)-3-methoxyphenyl)-5-hydroxyhepta-1,4,6-trien-3-one, C29H34O6Br2), was prepared and its two-photon absorption (TPA) properties were described in the femtosecond regime. The experimental results showed that complex I exhibited relatively strong and wide-dispersed two-photon activities in the near-infrared (NIR) regime and the calculated TPA cross section of complex I was as high as 872 GM (1 GM = 10−50 cm4 s photon−1) in DMF. Additionally, complex I revealed its potential application as a biological fluorescent probe due to its good photo-physical properties and low cytotoxicity, as well as excellent stability and specificity for optical imaging of tumors. Complex I was characterized by single crystal X-ray diffraction too (CIF file CCDC no. 1412447). [ABSTRACT FROM AUTHOR]

Plant hormones play major roles in abiotic stress. This study shows that gibberellin acid-inefficient transgenic rice (Oryza sativa L.) is more tolerant to drought and salinity stress. We also investigated the underlying molecular mechanism by which plants respond to salinity and drought stress. We previously showed how the HD-Zip family I gene Oshox4 (Homeobox 4) regulates GA deactivation by controlling DELLA subfamily and rice GA 2-oxidase and GA 3-oxidase genes in rice. Here we investigated the role of rice Oshox4 gene for drought and salinity stress tolerance. Phenotypic analysis indicated that Oshox4 transgenic lines are more tolerant to drought and salinity stress relative to non-transgenic IR64 plants. To explain the strong osmotic stress tolerance of Oshox4 transgenic lines, we studied the expression of rice GA 2-oxidase, rice YABBY, rice KRP, and rice GRAS gene families. qRT-PCR results showed that OsGA2ox4, OsGA2ox6, OsGA2ox8, OsGAI and OsSCRL were highly expressed under severe drought in Oshox4 transgenic plants. Oshox4 enhanced the expression of OsGA2ox5, OsKRP2 and OsKRP5 under 50 mM salt treatment and OsSCRL under 200 mM salt treatment. Our findings have confirmed that Oshox4 transgenic rice plants are more tolerant to drought and salinity stress and that Oshox4 plays a role in rice osmatic tolerance. This study provides novel insights into methods of maintaining higher yield amidst a limited supply of water by improving physiological conditions. [ABSTRACT FROM AUTHOR]

A fast triple-parameter extremum seeking method is applied for jet control based on the pioneering work of Gelbert et al. (J Process Control 22(4):700, 2012). The simultaneous adaptation of three input parameters takes less time than the single-input adaptation of each parameter combined. The key enablers are phase-shifted sinusoids for the input each of which is evaluated by an extended Kalman filter (EKF). An acceleration of the adaption is obtained by a combined EKF coupling the output to all inputs. The method is illustrated for an analytical optimization problem and experimentally demonstrated for a turbulent jet mixing control. The considered Reynolds numbers Re D based on the jet exit diameter and velocity are 5700, 8000 and 13,300. The main jet is manipulated by a pulsed radially injected minijet which is varied by a mass flow controller and an electromagnetic valve up to high frequencies. The mixing performance is characterized by the centerline jet decay rate and monitored by a hot-wire sensor five diameters downstream at the end of the potential core. The proposed triple-parameter extremum seeking method optimizes the actuation mass flow ratio, frequency and duty cycle. The decay rate increases 11-fold from the unforced reference value of 0.05 to the optimal actuation level of 0.56. The reproducibility is demonstrated with various initial actuation parameters. Moreover, the adaptive control robustly tracks the optimal open-loop actuation for varying Re D ; the optimal decay rate remains unchanged given the mass flow rate, frequency and duty cycle are optimized. The unforced and actuated flow are investigated with hot wires and visualizations. The three-input ES significantly outperforms a two-parameter optimization for the same configuration in multiple respects (Wu et al. in AIAA J 56(4):1463, 2018): First, the jet decay rate is 8 % faster. Second, the convergence time for three parameters is only 25 % of the adaptation period of two parameters when Re D is varied. Finally, the current steady-state error is 45 % less than that of the two-parameter optimization. We expect the proposed triple-parameter extremum seeking to be applicable for a large range of flow control experiments. [ABSTRACT FROM AUTHOR]

Based on numerical calculations, we have found that thin hexagonal boron nitride nanodiscs support high-quality localized phonon polariton modes in the upper Reststrahlen band. Near the resonances, single disc can be phenomenologically considered as an electric dipole. By arranging discs into a square lattice, strong light absorptions can be achieved. Modeling such periodic systems as dipole lattices, simple reflecting substrates can be designed which lead to omnidirectional strong, even nearly perfect, light absorptions. Under the condition of nearly total absorption, the electric fields at the hexagonal boron nitride surfaces are largely enhanced due to low-loss localized phonon polaritons. Our investigations might be useful for phonon polariton–based nanophotonic devices, such as sensors. [ABSTRACT FROM AUTHOR]

A numerical investigation is carried out to study hydrodynamic behavior and thermal performance of slug flow in serpentine microchannel with different curvature ratio and wall properties. By using coupled Level Set and Volume of Fluid (CLSVOF) method implemented in Fluent, gas-liquid interface shows good consistency with experimental results especially for slug flow. Distribution of sectional velocity profile in curved microchannel with various curvature ratios was investigated. On the basis of fluid flow in microchannel with non-slip boundary condition, by means of user defined function (UDF), influence of slip velocity on hydrodynamic characteristics was performed numerically. For a better prediction on thermal performance, further analysis of combined effect of wall properties and curvature ratio on fluid flow characteristics was also conducted. As a consequence, the increasing slip velocity on channel wall can reduce hydraulic resistance. Both the contact angle and the curvature ratio have an appreciable influence on thermal performance of gas-liquid two-phase flow in serpentine microchannel. [ABSTRACT FROM AUTHOR]

Accurate assessing CO2 exchange of tundra ecosystems is essential for better understanding and prediction of the CO2 responses of tundra ecosystems to climate change. In this study, the effects of warming on growing season CO2 exchange in an alpine tundra ecosystem were examined with closed transparent chamber attached to an infrared gas analyzer. Compared to ambient controls, open-top chambers (OTCs) increased growing season air (15 cm above ground surface) and soil (10 cm in depth) temperature by 1 and 0.2°C, respectively. Compared to the controls, OTCs tended to increase the plant height of Dryas octopetala and Vaccinium uliginosum by 15.1% (but P > 0.05) and 7.5% (P > 0.05), respectively. During the growing season, OTC-warming increased net ecosystem CO2 exchange by 136% and gross ecosystem exchange by 63%, whereas no significant difference in ecosystem respiration was found. Our results suggest that the predicted air warming will increase ecosystem carbon uptake of the Changbai Mountain alpine tundra during growing season. However, there is an uncertainty about the net CO2 exchange of that ecosystem at an annual scale, because, due to the inaccessibility, we did not study the winter respiration. Further studies are, therefore, needed to estimate the annual and long-term trade-off between CO2 uptake and emission in that region. [ABSTRACT FROM AUTHOR]

A dioxomolybdenum(VI) complex [MoO2L(EtOH)] (I), derived from the hydrazone ligand 2‑bromo-N'-(3,5-dichloro-2-hydroxybenzylidene)benzohydrazide has been prepared and characterized by physico-chemical and spectroscopic methods, as well as single crystal X-ray diffraction (CIF file CCDC no. 1840671). The hydrazone ligand coordinates to the Mo atom through the phenolate oxygen, imino nitrogen, and enolic oxygen. The Mo atom is six-coordinate in an octahedral geometry. Complex I shows high catalytic activity and selectivity in the epoxidation of cyclohexene with tert-butylhydroperoxide as primary oxidant. [ABSTRACT FROM AUTHOR]

In this paper, hydrodynamic model has been analytically solved to investigate the nonlocal plasmons in cylindrically curved graphene layers. Within the quasi-static approximation, the dispersion relations for both local and nonlocal cases have been derived; the nonlocal effect is found to shift the dispersion relations upwards. High-order azimuthal modes possess different cutoff frequencies due to such nonlocality, which may occur even in large-scale highly doped structures. In periodically doped cases, the nonlocal effect can modify the corresponding plasmonic band structures, i.e., moving the locations of the bandgaps. The periodicity has made the material more sensitive to the plasmon nonlocality. Our investigations may lead to more attentions to the nonlocal plasmonic responses in graphene which are important for graphene-plasmon-based photonic devices. [ABSTRACT FROM AUTHOR]

In the recent publications (Gerace and Savona, Phys. Rev. A 89(R), 031803 2014; Zhou et al., Opt. Express 24, 17332 2016), the unconventional photon blockades are studied in a three-mode-second-order-nonlinearity system with linear coupling between the two low frequency modes. In this paper, the unconventional photon blockade is studied in a complementary case with linear coupling between the two high frequency modes. By solving the master equation in the steady-state limit and calculating the zerodelay- time second-order correlation function, a strong photon antibunching is found in this three-mode-second-order-nonlinearity system. The optimal antibunching conditions are derived and the numerical simulations confirm the optimal conditions. Our scheme can be used as a tunable single-photon source. [ABSTRACT FROM AUTHOR]

We have specialized astronomical applications for X-ray microcalorimeters with superconducting transition edge sensors (TESs) that require exceptionally good TES performance, but which operate in the small-signal regime. We have therefore begun a program to carefully characterize the entire transition surface of TESs with and without the usual zebra stripes to see if there are reproducible local “sweet spots” where the performance is much better than average. These measurements require precise knowledge of the circuit parameters. Here, we show how the Shapiro effect can be used to precisely calibrate the value of the shunt resistor. We are also investigating the effects of stress and external magnetic fields to better understand reproducibility problems. [ABSTRACT FROM AUTHOR]

Herein we report the synthesis and magnetic properties of a new one-dimensional Co(II) chain compound with the formula [Co(tricH4)Cl] (tricH5 = N-[tris(hydroxymethyl)methyl]glycine). In this structure, the cobalt ion has a slightly distorted octahedral coordination environment. TricH4 is a pentadentate ligand using one nitrogen and four oxygen atoms to coordinate to the Co(II) ions. The three hydroxyl groups are all not detprotonated and the carboxylate moiety of the tricH4 lignd is a bridge leading to a 1D chain. The crystal structure is stabilized by the intrachain and interchain hydrogen bonding. Magnetic susceptibility measurements exhibit only weak ferromagnetic exchange interactions found within the chain complex due to the carboxylate bridges. [ABSTRACT FROM AUTHOR]

Use of multidisciplinary analysis in reliability-based design optimization (RBDO) results in the emergence of the important method of reliability-based multidisciplinary design optimization (RBMDO). To enhance the efficiency and convergence of the overall solution process, a decoupling algorithm for RBMDO is proposed herein. Firstly, to decouple the multidisciplinary analysis using the individual disciplinary feasible (IDF) approach, the RBMDO is converted into a conventional form of RBDO. Secondly, the incremental shifting vector (ISV) strategy is adopted to decouple the nested optimization of RBDO into a sequential iteration process composed of design optimization and reliability analysis, thereby improving the efficiency significantly. Finally, the proposed RBMDO method is applied to the design of two actual electronic products: an aerial camera and a car pad. For these two applications, two RBMDO models are created, each containing several finite element models (FEMs) and relatively strong coupling between the involved disciplines. The computational results demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

The experimental identification of contact stress is important in many areas. In this paper, we present an inverse method for identifying the stress distribution on non-conforming contact interface based on local displacement measurements. A mechanical model is established to formulate the relationship between the contact stress and the displacement field near the interface. An optical method, named segmentation-aided digital image correlation is utilized to measure the near-field displacement. The contact stress is then inversed by finding the optimal model that best matches the measurements. Three model parameters, i.e., the contact center, contact length and maximum contact stress, are identified through an optimization procedure. The parameters are initialized by an image processing method and then iteratively refined by minimizing the discrepancy between the model predictions and the measured displacements. Both simulated and real-world experiments are conducted and the results verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Background: In England, 'fast-track' (also known as 'two-week wait') general practitioner referrals for suspected cancer in symptomatic patients are used to shorten diagnostic intervals and are supported by clinical guidelines. However, the use of the fast-track pathway may vary for different patient groups.Methods: We examined data from 669 220 patients with 35 cancers diagnosed in 2006-2010 following either fast-track or 'routine' primary-to-secondary care referrals using 'Routes to Diagnosis' data. We estimated the proportion of fast-track referrals by sociodemographic characteristic and cancer site and used logistic regression to estimate respective crude and adjusted odds ratios. We additionally explored whether sociodemographic associations varied by cancer.Results: There were large variations in the odds of fast-track referral by cancer (P<0.001). Patients with testicular and breast cancer were most likely to have been diagnosed after a fast-track referral (adjusted odds ratios 2.73 and 2.35, respectively, using rectal cancer as reference); whereas patients with brain cancer and leukaemias least likely (adjusted odds ratios 0.05 and 0.09, respectively, for brain cancer and acute myeloid leukaemia). There were sex, age and deprivation differences in the odds of fast-track referral (P<0.013) that varied in their size and direction for patients with different cancers (P<0.001). For example, fast-track referrals were least likely in younger women with endometrial cancer and in older men with testicular cancer.Conclusions: Fast-track referrals are less likely for cancers characterised by nonspecific presenting symptoms and patients belonging to low cancer incidence demographic groups. Interventions beyond clinical guidelines for 'alarm' symptoms are needed to improve diagnostic timeliness. [ABSTRACT FROM AUTHOR]

Hybrid compound 1-(2-fluro-4-bromobenzyl)-4-dimethylaminopyridium bis(maleonitriledithiolate) cuprate(II) [2F4BrBzDMAP]2[Cu(mnt)2] is prepared and characterized by X-ray diffraction. The compound crystallizes in the triclinic system with the space group P-1. The unit cell dimensions are a = 8.9813(11), b = 9.0794(12), c = 13.1082(17) Å and α = 88.179(2)°, β = 81.397(2)°, γ = 70.736(1)° with Z = 1. The structure consists of two [2F4BrBzDMAP]+ cations and one [Cu(mnt)2]2- anion. The cations of the title compound stack into a one-dimensional column through p∙∙∙π and π∙∙∙π interactions, and the anions (A) and cations (C) are arranged alternatively into one 1D column in an ∙∙∙A-CC-A-CC-A∙∙∙ sequence through C-H∙∙∙N hydrogen bonds and S∙∙∙N interactions. The presence of functional groups is confirmed by the FT-IR spectrum, and optical absorption is ascertained by the recorded UV-Visible spectrum. The thermal stability of the compound is determined by thermogravimetric and differential thermal analyses. The variable-temperature magnetic susceptibility measurement shows that the compound exhibits a weak ferromagnetic coupling behavior when the temperature is lowered. [ABSTRACT FROM AUTHOR]

The inexpensive cost and high manufacture efficient metal wire and arc additive manufacturing (WAAM) system was designed in this work. Its application potential was evaluated from the three aspects of formability, microstructures, and mechanical properties. By using compulsory cooling solution implemented in the open-source WAAM system, the complex-shaped metal parts were deposited completely with no obvious defects, such as cracks, pores, or incomplete fusion. The properties of the WAAM part were evaluated by optical microscopy (OM), scanning electron microscopy (SEM), microhardness, and microtensile test. The results indicate that the formability of metal parts fabricated by the open-source WAAM system was improved by using compulsory cooling solution. The microstructures of the WAAM part are exhibited as granular structure which consisted of the granular ferrite and the residual austenite interspersed with a little pearlite in the intermediate zone. And the average ferrite grain size of non-overlapping layer is relatively smaller than that of overlapping layer. The specimen perpendicular to the building direction exhibits a better mechanical property. [ABSTRACT FROM AUTHOR]

One-dimensional non-Darcy flow in a semi-infinite porous media is investigated. We indicate that the non-Darcy relation which is usually determined from experimental results can always be described by a piecewise linear function, and the problem can be equivalently transformed to a multiphase implicit Stefan problem. The novel feature of this Stefan problem is that the phases of the porous media are divided by hydraulic gradients, not the excess pore water pressures. Using the similarity transformation technique, an exact solution for the situation that the external load increases in proportion to the square root of time is developed. The study on the existence and uniqueness of the solution leads to the requirement of a group of inequalities. A similar Stefan problem considering constant surface seepage velocity is also investigated, and the solution, which we indicate to be uniquely existent under all conditions, is established. Meanwhile, the relation between our Stefan problem and the traditional multiphase Stefan problem is demonstrated. In the end, computational examples of the solution are presented and discussed. The solution provides a useful benchmark for verifying the accuracy of general approximate algorithms of Stefan problems, and it is also attractive in the context of inverse problem analysis. [ABSTRACT FROM AUTHOR]

The study on the unconventional photon blockade mainly focus on Kerr nonlinearity. In this paper, we study the unconventional photon blockade based on another kind of nonlinearity, that is two-photon tunneling. The optimal conditions for strong antibunching are found by analytic calculations and numerical simulations, and the results are compared with the unconventional photon blockade based on Kerr nonlinearity, we find that the two-photon tunneling system has advantages for the larger antibunching area. Finally, we show that, after the symmetric-antisymmetric mode transformation, the two kinds of nonlinearities are equivalent from the perspective of photon antibunching. [ABSTRACT FROM AUTHOR]

In order to understand the microbial community of the soil ecosystems in rubber plantations, we investigated the functional diversity of soil microbial communities in young, mature and old rubber plantations in Hainan province, China. It was found that long-term cultivation of rubber trees altered the functional diversity of the soil microbial community. Microbial biomass and activity of the soil microbial community as well as its capacity for carbon utilisation and function diversity were shown to decline with an increase of the rubber plantation's age. The functional diversity of the soil microbial communities was similar in young and mature rubber plantations, but different from old rubber plantations. Total nitrogen, soil organic carbon, soil moisture, soil total porosity and capillary porosity were the key factors that influenced the functional diversity of the soil microbial communities in rubber plantations. [ABSTRACT FROM AUTHOR]

The best asymptotic constant for k-th order Markov inequality on a general compact set is determined. [ABSTRACT FROM AUTHOR]

A novel optical property of a conventional two-dimensional dielectric photonic crystal (PC) has been reported by establishing a Dirac cone at the Г point of its band structure: it manipulates waves as if it had zero refractive indices at the Dirac point frequency (Huang et al. in Nature Mater 10:582-586, 2011). However, this PC is not a real homogeneous material. What is the difference between it and a real zero-index material (ZIM) is a fundamental issue of physics itself and also crucial to their applications. In this paper, through investigating the dispersion relations and the transmission properties of this kind of PC, we found that under normal incidence, at the frequency of the Dirac point, this PC does behave like a ZIM material. However, under oblique incidence, nonzero transmittances are obtained even at large incident angles, which is quite different from the real ZIM. The physical reason of the transmission properties was also investigated. It was found that near the Г point, there is an additional flat dispersion surface which intersects with the Dirac cone at the Dirac point. It is this flat dispersion surface which supports the Dirac point energy to exist in this PC, resulting in the nonzero transmission under oblique incidence. [ABSTRACT FROM AUTHOR]

Hot roll bonding of 4343/4A60 aluminum alloy has been performed in the Gleeble-3500 thermal simulator. The bonding process constitutive behavior has been analyzed. The results show that the peak flow stress decreases with the deformation temperature and strain rate reduction. An Arrhenius-type constitutive equation is used to describe the constitutive behavior of the hot-rolled 4343/4A60 aluminum alloy with the thermal deformation activation energy Q = 118.48 kJ/mol. The alloy microstructure and dynamic recrystallization are studied using the optical microscope. It is revealed that in the temperature range between 573 and 623 K the dynamic recovery has a strong effect on the alloy microstructure evolution. It has been also concluded that the dynamic recovery is the basic softening mechanism of 4343/4A60 composite. [ABSTRACT FROM AUTHOR]

Sliding wear tests of Ti-6Al-4V alloy against AISI 52100 steel were performed at room temperature. For the sake of improving the worse wear performance of the titanium alloy, an attempt of inducing the accelerated formation of protective tribo-oxide layers was made by artificially supplying nanoscale oxides of TiO, FeO or their mixtures onto sliding tracks. FeO nanoparticles were noticed to have an advantage over TiO in the formation of sustainable tribo-oxide layers under higher load, which was ascribed to their rapid sintering rate and excellent load-carrying capability. The existence of FeO and FeO-rich tribo-layers markedly reduced the wear rate of Ti-6Al-4V alloy under 10-50 N, whereas TiO and TiO-rich nanoparticles as abrasives promoted wear in most cases. Clearly, TiO and FeO nano-oxides as main ingredients of tribo-layers presented the opposite function in the sliding wear of Ti-6Al-4V alloy. In the titanium alloy/steel sliding system, the wear-reducing function of tribo-layers was suggested to be attributed to the appearance of FeO, not TiO. [ABSTRACT FROM AUTHOR]

Suaeda salsa is a succulent halophyte belonging to Suaedoideae; sodium, chloride and sulfate ions or combination of the ions were useful to its growth. The seed germination is important event in plants life cycle, and it is sensitive to salt stress. To further understand the molecular mechanisms of S. salsa seed germination under salt stress, cDNA-AFLP and qRT-PCR were used to identify genes differentially expressed during seed germination under 100 mM NaCl stress (0, 12, 24, 36, 48, and 60 h), and 113 transcript derived fragments (TDFs) over 80 bp in length were identified using cDNA-AFLP. Gene ontology analysis revealed that these genes were involved in stress response, signal transduction and protein synthesis, etc. Further, four genes closely related to salt resistance were selected and their expression during S. salsa seed germination were investigated by qRT-PCR. The result showed differential gene expression at various germination stages under salt stress. Further work will be focused on cloning these genes and identifying their functions in S. salsa germination process under salt stress. [ABSTRACT FROM AUTHOR]

The closed-loop control of a turbulent round air jet is experimentally investigated based on two unsteady minijets, with a view to enhancing jet mixing. The two minijets are placed at diametrically opposite locations upstream of the nozzle exit. The open-loop control experiments are first performed. Given the mass flow rate ratio C of the minijets to that of the main jet, the decay rate $$\overline{K}$$ of jet centerline mean velocity exhibits a maximum at the frequency ratio f / f ≈ 1.0, where f and f are the excitation frequency of minijets and the preferred mode frequency of the natural main jet, respectively. An extremum-seeking feedback control has been developed to achieve autonomously the optimal control performance. It has been found that, given C , this closed-loop control technique may obtain automatically and rapidly the optimal value of f and the desired or maximum $$\overline{K}$$ , as achieved in the open-loop control. This control technique is robust and adaptable when the Reynolds number and initial excitation frequency are changed separately. A flow-physics-based feedback control strategy has also been investigated, which could achieve the optimal control performance automatically with a shorter convergence time than the extremum-seeking control, not robust though. [ABSTRACT FROM AUTHOR]

Modifiers of response to glucose, insulin and potassium (GIK) infusion may affect clinical outcomes in acute coronary syndromes (ACS). In an Immediate Myocardial Metabolic Enhancement During Initial Assessment And Treatment In Emergency Care (IMMEDIATE) trial's sub-study (n=318), we explored effects of 132 634 genetic variants on plasma glucose and potassium response to 12-h GIK infusion. Associations between metabolite-associated variants and infarct size (n=84) were assessed. The 'G' allele of rs12641551, near ACSL1, as well as the 'A' allele of XPO4 rs2585897 were associated with a differential glucose response (P for 2 degrees of freedom test, P2df⩽4.75 × 10-7) and infarct size with GIK (P2df<0.05). Variants within or near TAS1R3, LCA5, DNAH5, PTPRG, MAGI1, PTCSC3, STRADA, AKAP12, ARFGEF2, ADCYAP1, SETX, NDRG4 and ABCB11 modified glucose response, and near CSF1/AHCYL1 potassium response (P2df⩽4.26 × 10−7), but not outcomes. Gene variants may modify glucose and potassium response to GIK infusion, contributing to cardiovascular outcomes in ACS. [ABSTRACT FROM AUTHOR]

Summary: Peripheral blood monocytes (PBMs) are an important source of precursors of osteoclasts, the bone-resorbing cells and the cytokines produced by PBMs that have profound effects on osteoclast differentiation, activation, and apoptosis. So PBMs represent a highly valuable and unique working cell model for bone-related study. Finding an appropriate working cell model for clinical and (epi-)genomic studies of human skeletal disorders is a challenge. Peripheral blood monocytes (PBMs) can give rise to osteoclasts, the bone-resorbing cells. Particularly, PBMs provide the sole source of osteoclast precursors for adult peripheral skeleton where the bone marrow is normally hematopoietically inactive. PBMs can secrete potent pro- and anti-inflammatory cytokines, which are important for osteoclast differentiation, activation, and apoptosis. Reduced production of PBM cytokines represents a major mechanism for the inhibitory effects of sex hormones on osteoclastogenesis and bone resorption. Abnormalities in PBMs have been linked to various skeletal disorders/traits, strongly supporting for the biological relevance of PBMs with bone metabolism and disorders. Here, we briefly review the origin and further differentiation of PBMs. In particular, we discuss the close relationship between PBMs and osteoclasts, and highlight the utility of PBMs in study the pathophysiological mechanisms underlying various skeletal disorders. [ABSTRACT FROM AUTHOR]

Applying the operator method, general solutions for dynamic governing equations involving anisotropic piezoelectric materials are derived. Based on the general solutions, a rigid solid with a sinusoidal surface moving along the surface of anisotropic piezoelectric materials is concerned. Dual series equations are obtained and solved analytically. Then, the electro-elastic fields are determined in series forms. A full contact problem leads to more simple forms. Numerical analysis is performed for the anisotropic piezoelectric material $${0^{\circ }}$$ Graphite-epoxy, in which an illustrative example concerning the vertical mechanical displacement on the surface is displayed to validate the present approach. Results demonstrate that the contact behavior is considerably affected by both the velocity and material properties. [ABSTRACT FROM AUTHOR]

In this paper, we propose segmentation-aided digital image correlation (SA-DIC) for measuring the deformation near the interface between two contact bodies. Conventional DIC assumes that the shape function correctly warps a square subset from the reference image to the deformed image. When the subset is close to the contact interface, it contains pixels from the two contact bodies and the background if clearance is present. The displacement field in the subset is greatly complicated by the induced discontinuity and mismatches the shape function. To resolve this problem, SA-DIC automatically segments the image pixels into three categories: the two contact bodies and the invalid area. By using complementary speckle patterns, the contact interface exhibits a sharp intensity transition and it is extracted by edge detection. The background pixels are identified from the difference of the reference image pair captured with distinct background. Based on the image segmentation, only the pixels belonging to the same category are included in the subset. Their displacements are homogeneous and thus well characterized by the shape function used in DIC. Both simulated and real-world experiments are carried out to evaluate the proposed method and compare with conventional DIC. The results show that SA-DIC is able to measure the localized deformation due to the contact, while conventional DIC generates large errors near the contact interface and falsely locates the most deformed areas. [ABSTRACT FROM AUTHOR]

RNA interference (RNAi) is a promising tool for cancer therapy, but its delivery strategy is a major challenge for its application. Oncolytic herpes simplex virus type 1 (HSV-1) is not only an effective antitumor drug but also an excellent vector. Herein, RNAi of oncogenes Bcl-2 and Survivin was combined with oncolytic HSV-1 (ICP34.5-/ICP6-/ICP47-/CMV-GM-CSF) and a new vector HSV010-BS was constructed. Transfected cell viability assays and animal experiments revealed that the dual silencing of Bcl-2 and Survivin improved the antitumor effect of oncolytic HSV-1 in vitro and in vivo, while the antitumor effect was correlated with the phosphorylation levels of PKR of the tumor cells. The higher the phosphorylation levels of PKR of the tumor cells, the weaker the replication ability of oncolytic HSV-1, and the more powerful HSV010-BS was than its control vectors in inhibiting the growth of the tumor cells. The results provided direct supportive proofs for a new potential cancer therapy strategy. [ABSTRACT FROM AUTHOR]

Solar radio bursts are intense radio radiation sources that occur during the energy-release process and represent a hot topic in solar-physics and space-weather research. In this paper, we present a multimode prediction model for daily solar radio bursts. The model uses deep learning and machine learning to obtain data information from different dimensions and to establish the relationship between the characteristics of the solar active region on the solar surface and solar radio bursts. For this model, we use data from the Solar and Heliospheric Observatory (SOHO)/Michelson Doppler Imager (MDI) total solar magnetic map, the Royal Observatory of Belgium World Data Centre in Brussels, and NOAA sunspot parameters (including number, area, and type of sunspots) as inputs. The output results are then compared with the list of solar radio bursts recorded by the Radio Solar Telescope Network (RSTN) to determine whether solar radio bursts are present and to determine the key parameters for determining radio bursts. Based on 5449 days of observational data, we find that the prediction accuracy of the model is 0.898 ± 0.011, and that the number of sunspots is a key parameter in determining the occurrence of solar radio bursts. Specifically, when the number of sunspots is greater than 15, the probability of occurrence of solar radio bursts is greater than 90%. We have identified the key parameters and thresholds for determining solar radio bursts and highlighted the key parameters for space-weather prediction. In addition, the prediction model can also be used for predicting in other fields. [ABSTRACT FROM AUTHOR]

The aim of this study was the investigation of the effect of different YO additives on wear resistance of the hypereutectic Fe-Cr-C hardfacing coatings. The microstructures were observed by optical microscopy, field emission scanning electron microscopy and transmission electron microscopy, respectively. Meanwhile, the hardness was measured and the wear resistance was evaluated. Finally, the role of YO was discussed. The microstructures of the coatings consist of the primary (Cr, Fe)C carbide and eutectic structure [austenite + (Cr, Fe)C carbide]. Moreover, YO can refine the MC carbide and improve the wear resistance of coatings obviously. YO can absorb at the surface of the MC carbide and improve the wear resistance of the hypereutectic Fe-Cr-C hardfacing coatings. [ABSTRACT FROM AUTHOR]

Background:Chinese women tend to have small and dense breasts and ultrasound is a common method for breast cancer screening in China. However, its efficacy and cost comparing with mammography has not been evaluated in randomised trials.Methods:At 14 breast centres across China during 2008-2010, 13 339 high-risk women aged 30-65 years were randomised to be screened by mammography alone, ultrasound alone, or by both methods at enrolment and 1-year follow-up.Results:A total of 12 519 and 8692 women underwent the initial and second screenings, respectively. Among the 30 cancers (of which 15 were stage 0/I) detected, 5 (0.72/1000) were in the mammography group, 11 (1.51/1000) in the ultrasound group, and 14 (2.02/1000) in the combined group (P=0.12). In the combined group, ultrasound detected all the 14 cancers, whereas mammography detected 8, making ultrasound more sensitive (100 vs 57.1%, P=0.04) with a better diagnostic accuracy (0.999 vs 0.766, P=0.01). There was no difference between mammography and ultrasound in specificity (100 vs 99.9%, P=0.51) and positive predictive value (72.7 vs 70.0%; P=0.87). To detect one cancer, the costs of ultrasound, mammography, and combined modality were $7876, $45 253, and $21 599, respectively.Conclusions:Ultrasound is superior to mammography for breast cancer screening in high-risk Chinese women. [ABSTRACT FROM AUTHOR]