High inductive helical support provides a solution to controlling the alignment error of inner electrodes in magnetically insulated transmission lines (MITLs). Three-dimensional particle-in-cell simulations were performed to examine the current loss mechanism and the effects of structural parameters on electron flow in an MITL with a helical inductor. An empirical expression related to the ratio of electron current loss to anode current and the ratio of anode current to self-limited current was obtained. Electron current loss caused by helical inductor with different structures was displayed. The results indicate that the current loss in an MITL, near an inductive helical support, comprises both the inductor current and the electron current loss. The non-uniform structure and current of a helical inductor cause an abrupt change in the magnetic field near the helical support, which leads to anomalous behavior and current loss of electron flow. In addition, current loss in the inductive helical-supported MITL is negligible when the inductance of the support is sufficiently high. This work facilitates the estimation of electron current loss caused by the inductive helical support in MITLs.

The effect of maternal folate intake on small-for-gestational-age (SGA) births remains inconclusive. The present study aimed to investigate the associations of maternal folate intake from diet and supplements with the risk of SGA births using data from a cross-sectional study in Shaanxi Province of Northwest China. A total of 7307 women who were within 12 months (median 3; 10th–90th percentile 0–7) after delivery were included. Two-level models were adopted to examine the associations of folate (dietary folate, supplemental folic acid and total folate) intake with the risk of SGA births and birth weight Z score, controlling for a minimum set of confounders that were identified in a directed acyclic graph. Results showed that a higher supplemental folic acid intake during the first trimester was negatively associated with the risk of SGA births (≤60 d v. non-use: OR 0·80; 95 % CI 0·66, 0·96; >60 d v. non-use: OR 0·78; 95 % CI 0·65, 0·94; Ptrend = 0·010; per 10-d increase: OR 0·97; 95 % CI 0·95, 0·99). A higher total folate intake during pregnancy was associated with a reduced risk of SGA births (highest tertile v. lowest tertile: OR 0·77; 95 % CI 0·64, 0·94; Ptrend = 0·010; per one-unit increase in the log-transformed value: OR 0·81; 95 % CI 0·69, 0·95). A similar pattern was observed for the birth weight Z score. Our study suggested that folic acid supplementation during the first trimester and a higher total folate intake during pregnancy were associated with a reduced risk of SGA births.

Echinococcus granulosus sensu stricto (s.s.), Echinococcus multilocularis and Echinococcus canadensis are the common causes of human echinococcosis in China. An accurate species identification tool for human echinococcosis is needed as the treatments and prognosis are different among species. The present work demonstrates a method for the simultaneous detection of these three Echinococcus species based on multiplex polymerase chain reaction (mPCR). Specific primers of this mPCR were designed based on the mitochondrial genes and determined by extensive tests. The method can successfully detect either separated or mixed target species, and generate expected amplicons of distinct size for each species. Sensitivity of the method was tested by serially diluted DNA, showing a detection threshold as less as 0.32 pg for both E. granulosus s.s. and E. canadensis, and 1.6 pg for E. multilocularis. Specificity assessed against 18 other parasites was found to be 100% except weakly cross-react with E. shiquicus. The assay was additionally applied to 69 echinococcosis patients and 38 healthy persons, confirming the high reliability of the method. Thus, the mPCR described here has high application potential for clinical identification purposes, and can further provide a useful tool for evaluation of serology and imaging method.

Maternal effects on offspring seeds are mainly caused by seed position on, and the abiotic environment of, the mother plant. Seed heteromorphism, a special form of position effect, is the production by an individual plant of morphologically distinct seed types, usually with different ecological behaviours. Seed heteromorphism is assumed to be a form of bet hedging and provides an ideal biological model to test theoretical predictions. Most studies of maternal effects on seeds have focused on abiotic environmental factors and changes in mean seed traits of offspring. Suaeda salsa is an annual halophyte that produces dimorphic seeds within the same inflorescence. We tested the hypothesis that plants grown from brown seeds of S. salsa have a higher offspring brown seed:black seed morph ratio and variance in seed size than plants from black seeds. Results from a pot experiment showed that plants grown from brown seeds had a higher brown seed:black seed ratio than plants grown from black seeds. This is the first layer of dynamic bet hedging. Brown seeds had higher size variation than black seeds, and seeds produced by plants from brown seeds also had higher seed size variation than plants grown from black seeds. This is the second layer of dynamic bet hedging. Thus, the maternal effect of seed heteromorphism is dual dynamic bet hedging. Furthermore, for seed traits we verified for the first time the theoretical prediction that an increase in offspring size variability induces an increase in the mean size of offspring.

Cast tungsten carbide is widely used to reinforce iron or steel substrate surface composites to meet the demands of harsh wear environments due to its extremely high hardness and excellent wettability with molten steel. Cast tungsten carbide particle/steel matrix surface composites have demonstrated great potential development in applications under the abrasive working condition. The thermal shock test was used to investigate the fatigue behavior of the composites fabricated by vacuum evaporative pattern casting technique at different temperatures. At elevated temperatures, the fatigue behavior of the composites was influenced by the oxidation of tungsten carbide, producing WO3. Thermodynamic calculations showed that the W2C in the tungsten carbide particle was oxidized at an initial temperature of approximately 570 °C. The relationship between oxidation and thermal fatigue crack growth was investigated, and the results suggested that oxidation would become more significant with increasing thermal shock temperature. These findings provide a valuable guide for understanding and designing particle/steel substrate surface composites.

This paper presents a hybrid strategy-based coordinate controller with a novel nonlinear disturbance observer for autonomous underwater vehicle manipulator systems (UVMSs). This method can reduce the influence from external unknown disturbances, inner coupling effects and model uncertainties by using a modified disturbance observer. Considering the natural redundancy property of the UVMS, the redundancy resolution algorithm is often utilized to give desired trajectories in the vehicle–joint space. However, because of the calibration errors, assembling errors and numerical errors, these desired trajectories may not lead the end-effector to the goal point accurately. To realize accurate motion control even when small errors exist in the planning phase, a hybrid strategy is introduced to transform the controller in the joint–vehicle space to the controller in the task space. Numerical simulations based on a UVMS have been carried out to testify the effectiveness of the proposed coordinate controller and the hybrid strategy. During the simulations, unknown disturbances are exerted upon the system. The trajectory tracking and error fixing performances are discussed in comparative analyses. The controller also maintains robust characteristics in comparison with the passivity-based controller and the proposed controller but without the disturbance observer. Experiments are also carried out to test its performance.

Highly dense zirconia dental ceramic coatings were fabricated by aqueous electrophoretic deposition (EPD) and subsequently sintered between 1250 and 1450 °C. Microstructural examination revealed that aqueous EPDZrO2 coatings possessed a tetragonal phase structure and the grain size increased with increasing sintering temperature. Nanoindentation study proved that the aqueous EPDZrO2 coating also had excellent mechanical properties. The effect of different applied loads on hardness and elastic modulus of the 1350 °C-sintered sample at room temperature was investigated by the method of progressive multicycle measurement nanoindentation. The simulative experiment proved that hardness of aqueous EPDZrO2 exhibited reverse indentation size effect (ISE) behavior and then displayed the normal ISE response. The analysis indicates that the reverse ISE is attributed to the relaxation of surface stresses resulting from indentation cracks at small loads and normal ISE is caused by geometrically necessary dislocations. The tetragonal–monoclinic stress-induced phase transformation during nanoindentation is the primary cause of dental zirconia failures.

In this paper, we review the status of the multifunctional experimental platform at the National Laboratory of High Power Laser and Physics (NLHPLP). The platform, including the SG-II laser facility, SG-II 9th beam, SG-II upgrade (SG-II UP) facility, and SG-II 5 PW facility, is operational and available for interested scientists studying inertial confinement fusion (ICF) and a broad range of high-energy-density physics. These facilities can provide important experimental capabilities by combining different pulse widths of nanosecond, picosecond, and femtosecond scales. In addition, the SG-II UP facility, consisting of a single petawatt system and an eight-beam nanosecond system, is introduced including several laser technologies that have been developed to ensure the performance of the facility. Recent developments of the SG-II 5 PW facility are also presented.

Pangquangou National Nature Reserve is well known as ‘the distribution centre of Prince Rupprecht's larch (Larix principis-rupprechtii)' in China. Community variation in Prince Rupprecht's larch forest provides habitat heterogeneity for animals, especially for the endemic and endangered brown-eared pheasant (Crossoptlon mantchuricum). In this study a total of 120 quadrats (each 10×10m) were established to measure and record species composition and six environmental variables to examine the underlying variables that control community variation. We applied a multivariate regression tree analysis to detect community variation, and used redundancy analysis-based variation partitioning to separate the effects of environmental variables on community variation. The results show that Prince Rupprecht's larch forest in the Pangquangou National Nature Reserve can be represented by eight community types. The amount of total species variability captured by all environmental variables was 20.6%, and the cumulative percentage variance of species–environment relationships was 95.8%. However, analyses with a conditional effect approach revealed that elevation, aspect and litter thickness contribute the most to community variation. The pure and joint effects of these three explanatory variables were separated with variation partitioning analyses. The results highlight that the effect of elevation accounts for the largest fraction of community variation in Prince Rupprecht's larch forest.

The effect of Cu addition varied from 0 to 4 mass% on the corrosion resistance and electrochemical response in Ni–Co–Cr–Mo alloys was investigated using potentiodynamic polarization, electrochemical impedance spectroscopy, and Mott–Schottky analysis. Results indicate that the Ni–Co–Cr–Mo alloy with 2 mass% Cu exhibited the most superior corrosion resistance, and the presence of Cu greatly influenced the outer porous layer. The Ni–Co–Cr–Mo alloys’ corrosion resistance was not simply increasing with copper addition increasing from 0 to 4 mass%. The X-ray photoelectron spectroscopy etching analysis was also conducted to illustrate the fraction of Cu at various depths in the passive film, and the results reveal that a maximum limit on Cu content (appropriately 3.10 mass%) existed in the outermost surface in the present condition. Among the studied alloys, the Ni–Co–Cr–Mo–2%Cu alloy formed the thickest passive film with the lowest donor density.

The structure and function of grassland ecosystems can be altered by a changing climate, including higher temperature and elevated atmospheric CO2 concentration. Previous studies suggest that there is no consistent trend in seed germination and seedling recruitment as affected by these conditions. We collected seeds of two native and two invasive species over 6 years from a field study with elevated CO2 (600 p.p.m.) and temperature (1.5/3.0°C day/night) on the mixed-grass prairie of Wyoming, USA. Seed fill, viability and mass were evaluated and germination tests were conducted under alternating temperatures in growth chambers. Thermal time requirements to reach 50% germination (θ50) and base temperatures (Tb) for germination were determined using thermal time models. Climate change conditions had limited effects on seed fill, viability and mass. The combination of CO2 enrichment and warming increased germination of Bouteloua gracilis. Centaurea diffusa and Linaria dalmatica, two invasive species in this study, had the lowest θ50 and Tb required for germination among all the species studied. Although final germination percentages of these invasive species were not affected by treatments, previous studies reported increased seed production under future climate conditions, indicating that they could be more invasive at the regeneration stage in the future. We conclude that projected future temperature increases will have little effect on seed reproductive traits of native species. In addition, the distribution and abundance of B. gracilis and invasive species may be favoured by global climate change due to enhanced germination or seed production traits caused by elevated parental CO2 and temperature conditions.

An all-fiberized high-average-power narrow linewidth ns pulsed laser with linear polarization is demonstrated. The laser system utilizes a typical master oscillator power amplifier (MOPA) configuration. The stimulated Brillouin scattering (SBS) is effectively suppressed due to the short fiber length and large mode area in the main amplifier, combined with the narrow pulse duration smaller than the phonon lifetime of SBS effect. A maximal output power of 466 W is obtained with a narrow linewidth of ${\sim}$ 203.6 MHz, and the corresponding slope efficiency is ${\sim}$ 80.3%. The pulse duration is condensed to be ${\sim}$ 4 ns after the amplification, corresponding to the peak power of 8.8 kW and the pulse energy of $46.6~\unicode[STIX]{x03BC}\text{J}$ . Near-diffraction-limited beam quality with an $M^{2}$ factor of 1.32 is obtained at the output power of 442 W and the mode instability (MI) is observed at the maximal output power. To the best of our knowledge, this is the highest average output power of the all-fiberized narrow linewidth ns pulsed fiber laser with linear polarization and high beam quality, which is a promising source for the nonlinear frequency conversion, laser lidar, and so on.

Valvular heart diseases lead to over 300,000 heart valve replacements worldwide each year. Bioprosthetic heart valves (BHVs), derived from glutaraldehyde (GLUT) crosslinked porcine or bovine pericardium, are often used. However, valve failure can occur within 12–15 years due to progressive degradation and/or calcification. Being innovated by previous amino reagent studies used for GLUT detoxification and carbodiimide [1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, EDC] chemistry, in this study, we developed a new fabrication method that utilizes exogenous amino donor arginine or lysine carbodiimide combined treatments to better stabilize the extracellular matrix of porcine pericardium. The carboxyl group density, amine content, differential scanning calorimetry, collagenase and elastase degradation, calcification by rat subdermal implantation, cytotoxicity, and platelet adhesion were characterized. We demonstrated that exogenous amino donor carbodiimide combined treatment for pericardiums had better resistance to elastase degradation (1.63 ± 0.11% and 1.44 ± 0.24% in arginine or lysine versus 3.68 ± 0.16% and 3.04 ± 0.11% in GLUT and GLUT/EDC control) and calcification (0.624 ± 0.193 and 0.637 ± 0.213 Ca µg/mg tissue in arginine or lysine versus 1.610 ± 0.124 and 1.512 ± 0.075 Ca µg/mg tissue in GLUT and GLUT/EDC control). This new strategy combined arginine or lysine and carbodiimide crosslinking would be a promising method to produce more robust BHVs with better structural stability and anticalcification property.

Knowledge about the infection transmission routes is significant for developing effective intervention strategies. We searched the PubMed databases and identified 10 studies with 14 possible inflight influenza A(H1N1)pdm09 outbreaks. Considering the different mechanisms of the large-droplet and airborne routes, a meta-analysis of the outbreak data was carried out to study the difference in attack rates for passengers within and beyond two rows of the index case(s). We also explored the relationship between the attack rates and the flight duration and/or total infectivity of the index case(s). The risk ratios for passengers seated within and beyond the two rows of the index cases were 1.7 (95% confidence interval (CI) 0.98–2.84) for syndromic secondary cases and 4.3 (95% CI 1.25–14.54) for laboratory-confirmed secondary cases. Furthermore, with an increase of the product of the flight duration and the total infectivity of the index cases, the overall attack rate increased linearly. The study indicates that influenza A(H1N1)pdm09 may mainly be transmitted via the airborne route during air travel. A standardised approach for the reporting of such inflight outbreak investigations would help to provide more convincing evidence for such inflight transmission events.

Sulphur isotopes can be used as a powerful tool to trace fluid evolution and explore the formation of chimneys. To clarify the in situ S isotopic variations of sulphides at the micro-scale, we analyzed a sulphide chimney collected from the hydrothermal field in the East Pacific Rise 1–2° S using a sensitive high-mass-resolution ion micro-probe for stable isotopes (SHRIMP SI). Three mineral zones can be identified in the chimney: an external outer wall of porous anhydrite and colloform pyrite, an internal middle zone of sub-euhedral pyrite and massive chalcopyrite, and an inner zone of massive pyrite. The δ34SV-CDT values of the sulphides fall within the range 1.83–7.51 ‰ (avg. 4.05 ‰, n = 16), and S isotopic values increase from the core (3.09 ‰, n = 3) to the middle (3.78 ‰, n = 11) to the edge (6.99 ‰, n = 2). These results illustrate mineral crystallization processes and the mixing between seawater-derived S and magmatic–hydrothermal fluids during the growth of the chimney. The zones from the edge to the core are characterized by crystal morphologies of colloform/anhedral pyrite to massive pyrite with decreasing δ34S values, revealing multi-stage mineral deposition and sulphur isotopic fractionation. In contrast to the increase in δ34S values from the core to the edge in one profile (profile A), anomalously low δ34S values in fine-grained pyrite relative to chalcopyrite in another profile (profile B) in the middle zone result from S isotopic exchange between seawater SO42− and fluid H2S due to different fluid–seawater mixing, possibly caused by variations in permeability and porosity across the chimney.

Influenza is a long-standing public health concern, but its transmission remains poorly understood. To have a better knowledge of influenza transmission, we carried out a detailed modelling investigation in a nosocomial influenza outbreak in Hong Kong. We identified three hypothesised transmission modes between index patient and other inpatients based on the long-range airborne and fomite routes. We considered three kinds of healthcare workers’ routine round pathways in 1140 scenarios with various values of important parameters. In each scenario, we used a multi-agent modelling framework to estimate the infection risk for each hypothesis and conducted least-squares fitting to evaluate the hypotheses by comparing the distribution of the infection risk with that of the attack rates. Amongst the hypotheses tested in the 1140 scenarios, the prediction of modes involving the long-range airborne route fit better with the attack rates, and that of the two-route transmission mode had the best fit, with the long-range airborne route contributing about 94% and the fomite route contributing 6% to the infections. Under the assumed conditions, the influenza virus was likely to have spread via a combined long-range airborne and fomite routes, with the former predominant and the latter negligible.