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English vocabulary has expanded over centuries by ‘borrowing’ lexical items from other languages (Katamba, 2005; Durkin, 2014). Compared with European languages, non-European languages are never major sources of word borrowing in English, with Chinese staying even more peripheral. Scholars have recorded no more than a few hundred English words of Chinese origin. This, however, does not make it easier to study the etymology and semantics of Chinese loanwords. The complication arises from the various source dialects from which Chinese words were borrowed (Mandarin, Cantonese, Amoy, Hokkien, etc.) and also from transcription processes, in which Chinese logograms are ‘romanised’ into phonetic representations so as to be readable for English speakers. It is a procedure easily affected by the transcribers' own cognition and the transcription systems employed, and the arbitrariness of the above variables contributes much to the fact that the orthography of Chinese loanwords, especially those entering the English language early, are prone to changes. This article aims to shed some light on how the ways of transcription may affect the spelling of Chinese loanwords.
We present a study of absolute and convective instabilities in electrohydrodynamic flow subjected to a Poiseuille flow (EHD-Poiseuille). The electric field is imposed on two infinite flat plates filled with a non-conducting dielectric fluid with unipolar ion injection. Mathematically, the dispersion relation of the linearised problem is studied based on the asymptotic response of an impulse disturbance imposed on the base EHD-Poiseuille flow. Transverse, longitudinal and oblique rolls are investigated to identify the saddle point satisfying the pinching condition in the corresponding complex wavenumber space. It is found that when the ratio of Coulomb force to viscous force increases, the transverse rolls can transit from convective instability to absolute instability. The ratio of hydrodynamic mobility to electric mobility, which exerts negligible effect on the linear stability criterion when the cross-flow is small, has significant influence on the convective–absolute instability transition, especially when the ratio is small. As we change the value of the mobility ratio, a saddle point shift phenomenon occurs in the case of transverse rolls. The unstable longitudinal rolls are convectively unstable as long as there is a cross-flow, a result which is deduced from a one-mode Galerkin approximation. Longitudinal rolls have a larger growth rate than transverse rolls except for a small cross-flow. Finally, regarding the oblique rolls, a numerical search for the saddle point simultaneously in the complex streamwise and transverse wavenumber spaces always yields an absolute transverse wavenumber of zero, implying that oblique rolls give way to transverse rolls when the flow is unstable.
The strong interactions between Mg and Ni/NiH4 are attributed to harsh operating conditions and difficulties for H2 release, restricting the practical applications of the Mg-based hydrides. In this study, a new method of interstitial nonmetals co-doping was proposed to reduce the strong interactions. The calculation results showed that the method of interstitial nonmetals co-doping causes a more significant reduction in the thermal stability of Mg-based hydrides, as compared with the methods of either single transition metal or nonmetal doping. To determine the influence mechanism, a theoretical study was conducted based on the first-principles calculations. The computations demonstrated that the criss-cross action between B–Ni and N–Mg bonds weakens the bonding effects between Mg and Ni/NiH4. Besides, the mutual interactions between nonmetals and H atoms could weaken Ni–H bonding effects and stimulate the breaking of stable NiH4 clusters, thereby facilitating the release of H2 from the hydride.
The valence states, the distribution of Co ions, and defect structures in the Co-doped ITO films with Co concentrations of 5–13 at.% were examined by X-ray absorption spectroscopy (XAS) at Co, K, and L-edges. The structural analyses and ab initio calculations reveal that the Co atoms are substantially incorporated into the ITO lattice and form cobalt–vacancy complexes, while partial formation of Co0 species is observed for all the films. The analyses of Co–K edge XAS reveal that the Co–O bond length RCo–O is shortened and the corresponding Debye–Waller factor (σ2) obviously increases with Co doping, implying the relaxation of oxygen environment around the substitutional Co ions. The qualitative fitting of Co L3-edge XAS further confirms the coexistence of Co0 and Co2+ in the films. The Co atoms mainly occupy the substitutional sites of In2O3 lattices with the metallic Co clusters being about 20–43 at.% for the 5, 7, and 8.5 at.% Co-doped ITO films. However, a significant fraction (∼57 at.%) of metallic Co clusters is found in the 13 at.% Co-doped ITO film.
Twin glaciers collapsed in 2016 near Aru Co, western Tibet and caused extreme loss to human beings. In this study, we attempted to track the dynamics of glaciers in the region, for example the glacier area and mass changes in Aru Co for the period 1971–2016, which were determined using topographic maps and Landsat images and ASTER-derived DEMs (2011–16), the Shuttle Radar Terrain Mission DEM (2000) and topographic maps (1971). Our results showed that the glacier area of Aru Co decreased by −0.4 ± 4.1% during 1971–2016. The geodetic mass-balance results showed that the glaciers in Aru Co lost mass at a rate of −0.15 ± 0.30 m w.e. a−1 during 1971–99, while they gained mass at a rate of 0.33 ± 0.61 m w.e. a−1 for the period 1999–2016. The twin glaciers experienced a larger negative mass budget than the others in the region before 1999. This process produced large amounts of meltwater, followed by a sustained increase in the meltwater on the pressure melting point, possibly in response to a period of positive mass balance (1999–2016) and then, transferred to the glacier bed until the glaciers collapsed.
The pathophysiology of cognitive impairment in patients with the major depressive disorder (MDD) may involve neuroinflammation mediated by cytokines.
The aim of this study was to examine the serum interleukin-6 (IL-6) levels, sustained attention, and their association in patients with MDD.
Thirty patients with MDD and 30 healthy controls were enrolled in this case-control study. Sustained attention was measured using the Rapid Visual Information Processing (RVP) task in the Cambridge Neuropsychological Tests Automated Battery. The serum IL-6 levels of all subjects were assessed by sandwich enzyme-linked immunosorbent assays.
There were significant differences in the log10RVP total hits, log10RVP total misses, and log10RVP mean latency between patients with MDD and healthy controls (F = 6.04, p = 0.017; F = 19.77, p < 0.0001; F = 14.42, p < 0.0001, respectively). The serum levels of Log10IL-6 were significantly higher in patients with MDD than in healthy controls (F = 192.27, p < 0.0001). The log10IL-6 levels were also positively correlated with the log10RVP mean latency in patients with MDD (r = 0.45, p = 0.013). A further stepwise multivariate regression analysis indicated that the log10IL-6 levels were significantly associated with the log10RVP mean latency in patients with MDD (β = 0.31, t = 2.41, p = 0.025).
Our data suggested that increased IL-6 levels were associated with the psychopathology of MDD, and that abnormal IL-6 levels were implicated in the impairment of sustained attention in patients with MDD.
Droplet dynamics in microfluidic applications is significantly influenced by surfactants. It remains a research challenge to model and simulate droplet behaviour including deformation, breakup and coalescence, especially in the confined microfluidic environment. Here, we propose a hybrid method to simulate interfacial flows with insoluble surfactants. The immiscible two-phase flow is solved by an improved lattice Boltzmann colour-gradient model which incorporates a Marangoni stress resulting from non-uniform interfacial tension, while the convection–diffusion equation which describes the evolution of surfactant concentration in the entire fluid domain is solved by a finite difference method. The lattice Boltzmann and finite difference simulations are coupled through an equation of state, which describes how surfactant concentration influences interfacial tension. Our method is first validated for the surfactant-laden droplet deformation in a three-dimensional (3D) extensional flow and a 2D shear flow, and then applied to investigate the effect of surfactants on droplet dynamics in a 3D shear flow. Numerical results show that, at low capillary numbers, surfactants increase droplet deformation, due to reduced interfacial tension by the average surfactant concentration, and non-uniform effects from non-uniform capillary pressure and Marangoni stresses. The role of surfactants on the critical capillary number (
) of droplet breakup is investigated for various confinements (defined as the ratio of droplet diameter to wall separation) and Reynolds numbers. For clean droplets,
first decreases and then increases with confinement, and the minimum value of
is reached at a confinement of 0.5; for surfactant-laden droplets,
exhibits the same variation in trend for confinements lower than 0.7, but, for higher confinements,
is almost a constant. The presence of surfactants decreases
for each confinement, and the decrease is also attributed to the reduction in average interfacial tension and non-uniform effects, which are found to prevent droplet breakup at low confinements but promote breakup at high confinements. In either clean or surfactant-laden cases,
first remains almost unchanged and then decreases with increasing Reynolds number, and a higher confinement or Reynolds number favours ternary breakup. Finally, we study the collision of two equal-sized droplets in a shear flow in both surfactant-free and surfactant-contaminated systems with the same effective capillary numbers. It is identified that the non-uniform effects in the near-contact interfacial region immobilize the interfaces when two droplets are approaching each other and thus inhibit their coalescence.
Two-dimensional scattering of a Gaussian beam by a homogeneous gyrotropic circular cylinder is presented. The incident Gaussian beam source is expanded as an approximate expression with Taylor's series. The transmitted field in the homogeneous gyrotropic cylinder is expressed in terms of the series of wave functions based on the integral equation. The unknown coefficients of the scattered fields are obtained with the aid of the boundary conditions of continuous tangential electric and magnetic fields. Some numerical results are presented and discussed. The result is in agreement with that available as expected when the Gaussian beam degenerates to a plane wave incidence case.
Al, Mn, Rb, Sr, Ba, Cs, Bi and Sb were measured at various depth intervals of a 41.6 m firn/ ice core drilled at an elevation of 7010 m near the top of Muztagh Ata glacier, east Pamirs (38˚17’ N, 75˚06’ E), central Asia. These data, spanning the mid-1950s to 2000, were obtained by analyzing 101 sections using a sector-field double-focusing inductively coupled plasma mass spectrometer (ICP-MS) instrument. This study provides the first time series for these metals from central Asia. Concentrations are 11.7–329 ng mL−1 for Al, 0.33–42.7 ng mL−1 for Mn, 0.42–17.8 ng mL−1 for Sr, 0.04–1.4 ng mL−1 for Rb, 0.18–10.4 ng mL−1 for Ba, 2–167 pg mL−1 for Cs, 2–51 pg mL−1 for Sb and 1–31 pg mL−1 for Bi. Large variations in metal concentrations were found during the study period. Pronounced increases in concentrations were observed for Sb and Bi from the mid-1960s to the beginning of the 1990s, suggesting increased anthropogenic sources of Sb and Bi in central Asia during the same period. However, the decrease of Sb and Bi concentrations during the mid- to late 1990s reflects a reduction in anthropogenic activities in central Asia.
We use topographic maps, historical data, multispectral satellite data and real-time kinematic GPS data to analyze glacier area, length and ice-elevation changes of two glaciers in the central Qilian Shan, China, between 1956 and 2007. We find that the fronts of Yanglonghe glacier No. 1 (5Y432A1) and Yanglonghe glacier No. 5 (5Y432A5) have retreated by 266.5 ± 37.1 m (5.2 ± 0.73 m a−1) and 181.4 ± 37.1 m (3.6 ± 0.73 m a−1) respectively, and that this retreat accelerated after 1999. During the study period, the glacier areas decreased by ∼4.1% and 15.9% respectively. In addition, spatially non-uniform thinning, which averaged 20.2 ± 11 m (0.4 ± 0.22 m a−1) and 16.9 ± 11 m (0.33 ± 0.22 m a−1) in the ablation areas of 5Y432A1 and 5Y432A5 respectively, is observed using digital elevation models constructed using data from 1956, 1977 and 2007. The ice-volume depletion from 5Y432A1 (2.91 × 107 m3) was 2.7 times greater than from the smaller 5Y432A5 (1.08 × 107 m3). Based on records from nearby Tuole weather station, increasing annual temperatures are principally responsible for the observed glacier thinning and retreat.
A compact three-dimensional (3D) circularly polarized (CP) microstrip antenna is presented in this paper. The antenna adopts three low-cost printed circuit boards to form an integrated and closed 3D structure, and the radiation patch and the feed patches are etched on the surface of that. A crossed slot is cut on the radiation patch to miniaturize the antenna, and triangular feed patches are introduced to increase the bandwidths. In addition, because of the utilization of a low-loss series feed line, the antenna has a high efficiency of more than 95%. A prototype of the antenna is measured to validate the method. The dimensions of the antenna is 0.064λ × 0.36λ (λ is the wavelength in free space at 1.2 GHz). The results indicate that the impedance bandwidth for voltage standing wave ratio ≤ 2 reaches 23%, and the bandwidth for axial ratio (AR) ≤ 3 dB reaches 10.1%. In the overlap band, the gains are > 4.5dBic. Additionally, the 3 dB beamwidth is more than 114°, and the beamwidth for AR ≤ 3 dB is more than 131° at 1.2 GHz.
An effective multiplex real-time polymerase chain reaction (PCR) assay for the simultaneous detection of three major pathogens, Nosema bombycis Nägeli (Microsporidia: Nosematidae), Bombyx mori nucleopolyhedrovirus (Baculoviridae: genus Alphabaculovirus) (NPV), and Bombyx mori densovirus (Parvoviridae: genus Iteravirus) (DNV), in silkworms (Bombyx mori (Linnaeus); Lepidoptera: Bombycidae) was developed in this study. Polymerase chain reaction and real-time PCR tests and basic local alignment search tool searches revealed that the primers and probes used in this study had high specificities for their target species. The ability of each primer/probe set to detect pure pathogen DNA was determined using a plasmid dilution panel, in which under optimal conditions the multiplex real-time PCR assay showed high efficiency in the detection of three mixed target plasmids with a detection limit of 8.5×103 copies for N. bombycis and Bombyx mori NPV (BmNPV) and 8.5×104 copies for Bombyx mori DNV (BmDNV). When the ability to detect these three pathogens was examined in artificially inoculated silkworms, our method presented a number of advantages over traditional microscopy, including specificity, sensitivity, and high-throughput capabilities. Under the optimal volume ratio for the three primer/probe sets (3:2:2=N. bombycis:BmNPV:BmDNV), the multiplex real-time PCR assay showed early detection of BmNPV and BmDNV by day 1 post inoculation using DNA templates of the three pathogens in various combinations from individually infected silkworms; the early detection of N. bombycis was possible by day 3 post inoculation using the DNA isolated from the midgut of N. bombycis-infected silkworms.
The NaLa(MoO4)2:Yb3+/Er3+ phosphor is synthesized through hydrothermal method with the further calcinations. The intense green upconversion (UC) emission is observed when it is excited by 980 nm pump power. Then we investigate the mechanism of UC emission based on the power dependent upconversion luminescence (UCL) spectra. Temperature sensing performance based on the Stark levels (2H11/2/4S3/2) of Er3+ is estimated through investigating temperature-dependent UCL spectra from 298 K to 573 K. And the maximum value of sensor sensitivity based on FIR is approximately 0.00474 K−1. Moreover, the variations of UCL intensities from 2H11/2/4S3/2 → 4I15/2 transitions have been monitored with increasing pump power, which suggests that the pump energy can be absorbed by sample and heat it. In addition, the internal temperature of materials can be estimated by FIR technique. All the experimental results indicate that the phosphor has good potential in optical temperature sensing and optical heating.
To explore the 3-tiered treatment model for medical treatment after an earthquake.
Based on the practices of the national emergency medical rescue services in the Lushan earthquake zone, the 3-tiered treatment classification approach was retrospectively reviewed.
Medical rescue teams assembled and reported quickly to the disaster areas after the earthquake. The number of injured people had reached 25,176 as of April 30; of these, 18,611 people were treated as outpatients, 6565 were hospitalized, and 977 were seriously or severely injured.
The 3-tiered treatment model was the main approach used by rescue services after the Lushan earthquake. Primary and secondary treatments were of the highest importance and formed the basis of the Lushan model of earthquake rescue and treatment. (Disaster Med Public Health Preparedness. 2018; 12: 301–304)
A series of Ag2S/Ag2WO4 composite microrods with different Ag2S contents (10–50 wt%) were synthesized via a facile successive precipitation route. The texture and optical properties of the pure Ag2S, Ag2WO4, and Ag2S/Ag2WO4 composites were intensively characterized by some physicochemical characterizations like N2 physical adsorption, x-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, Ultraviolet–visible spectroscopy, x‐ray photoelectron spectroscopy, photoluminescence spectroscopy, and photocurrent measurements. Under visible light irradiation, different organic dyes, e.g., methylene blue and methyl orange dye were applied to evaluate the photocatalytic performances by their photocatalytic degradation reactions. The Ag2S/Ag2WO4 composite microrods exhibited superior photocatalytic activity and stability. The high crystallinity of Ag2WO4 and improved texture properties of Ag2S/Ag2WO4 resulted in their enhanced photocatalytic property. More importantly, the Ag2S/Ag2WO4 heterojunctions with matching electronic band structures obviously enhanced the separation of photo‐generated electrons and holes, further promoting the photocatalytic reaction.
Choline and betaine are essential nutrients involved in one-carbon metabolism and have been hypothesised to affect breast cancer risk. Functional polymorphisms in genes encoding choline-related one-carbon metabolism enzymes, including phosphatidylethanolamine N-methyltransferase (PEMT), choline dehydrogenase (CHDH) and betaine-homocysteine methyltransferase (BHMT), have important roles in choline metabolism and may thus interact with dietary choline and betaine intake to modify breast cancer risk. This study aimed to investigate the interactive effect of polymorphisms in PEMT, BHMT and CHDH genes with choline/betaine intake on breast cancer risk among Chinese women. This hospital-based case–control study consecutively recruited 570 cases with histologically confirmed breast cancer and 576 age-matched (5-year interval) controls. Choline and betaine intakes were assessed by a validated FFQ, and genotyping was conducted for PEMT rs7946, CHDH rs9001 and BHMT rs3733890. OR and 95 % CI were estimated using unconditional logistic regression. Compared with the highest quartile of choline intake, the lowest intake quartile showed a significant increased risk of breast cancer. The SNP PEMT rs7946, CHDH rs9001 and BHMT rs3733890 had no overall association with breast cancer, but a significant risk reduction was observed among postmenopausal women with AA genotype of BHMT rs3733890 (OR 0·49; 95 % CI 0·25, 0·98). Significant interactions were observed between choline intake and SNP PEMT rs7946 (Pinteraction=0·029) and BHMT rs3733890 (Pinteraction=0·006) in relation to breast cancer risk. Our results suggest that SNP PEMT rs7946 and BHMT rs3733890 may interact with choline intake on breast cancer risk.
Increasing dietary Ca intake may prevent the excessive mobilisation of bone mineral in nursing mothers. We aimed to investigate whether higher Ca intake could positively modulate the bone mineral changes in Chinese postpartum lactating women. The study was a 12-month randomised, double-blinded, parallel group trial conducted over 12 months. A total of 150 postpartum women were randomly selected to receive either 40 g of milk powder containing 300 mg of Ca and 5 μg of vitamin D (Low-Ca group) or same milk powder additionally fortified with 300 mg of Ca (Mid-Ca group) or 600 mg of Ca (High-Ca group). Bone mineral density (BMD) for the whole body, the lumbar spine, the total left hip and its sub-regions was measured using dual-energy X-ray absorptiometry. A total of 102 subjects completed the whole trial. The duration of total lactating time was 7·9 (sd 2·8) months on average. The intention-to-treat analysis yielded the following mean percentage changes in BMD for the whole body, the lumbar spine and the total left hip, respectively: −0·93 (sd 1·97), 2·11 (sd 4·90) and −1·60 (sd 2·65) % for the Low-Ca group; −0·56 (sd 1·89), 2·21 (sd 3·77) and −1·43 (sd 2·30) % for the Mid-Ca group; and −0·44 (sd 1·67), 2·32 (sd 4·66) and −0·95 (sd 4·08) % for the High-Ca group. The differences between the groups were not statistically significant (P: 0·5–0·9). The results of the complete case analysis were similar. In sum, we found no significant differences in the bone mineral changes from baseline to 12 months in postpartum lactating women consuming milk powder fortified with different levels of Ca.
The thermodynamic solubility product for baryte, determined at standard conditions, from data in commonly used compilations, was compared with published experimental solubility products for baryte and with the solubility products from databases used by the PHREEQC geochemical speciation code and MultiScale, which is often used by oil companies to predict or describe baryte scaling. The values in the various databases agree well with experimental data (10–10.05–10–9.96; Melcher, 1910; Neuman, 1933; Templeton, 1960; Davis and Collins, 1971; Blount, 1977; Felmy et al., 1990), which agree within uncertainty with the values presented in the compilations of Robie et al. (1979), Wagman et al. (1982), Lide (2005), Raju and Atkinson (1988), as well as Nordstrom and Munoz (1994), whose values have the least uncertainty. In solutions of 50% seawater mixed with 50% reservoir formation waters, the data predict baryte supersaturation, both at standard temperature and at the temperatures expected in the reservoir, completely consistent with field observations. This provides confidence that the Pitzer approach for activity correction and the database is valid for investigations of baryte precipitation rates in high ionic strength solutions.