Spatial profiles of impurity emission measurements in the extreme ultraviolet (EUV) spectroscopic range in radiofrequency (RF)-heated discharges are combined with one-dimensional and three-dimensional transport simulations to study the effects of resonant magnetic perturbations (RMPs) on core impurity accumulation at EAST. The amount of impurity line emission mitigation by RMPs appears to be correlated with the ion Z for lithium, carbon, iron and tungsten monitored, i.e. stronger suppression of accumulation for heavier ions. The targeted effect on the most detrimental high-Z impurities suggests a possible advantage using RMPs for impurity control. Profiles of transport coefficients are calculated with the STRAHL one-dimensional impurity transport code, keeping $\nu /D$ fixed and using the measured spatial profiles of $\textrm{F}{\textrm{e}^{20 + }}$, $\textrm{F}{\textrm{e}^{21 + }}$ and $\textrm{F}{\textrm{e}^{22 + }}$ to disentangle the transport coefficients. The iron diffusion coefficient ${D_{\textrm{Fe}}}$ increases from $1.0- 2.0\;{\textrm{m}^2}\;{\textrm{s}^{ - 1}}$ to $1.5- 3.0\;{\textrm{m}^2}\;{\textrm{s}^{ - 1}}$ from the core region to the edge region $(\rho \gt 0.5)$ after the onset of RMPs. Meanwhile, an inward pinch of iron convective velocity ${\nu _{\textrm{Fe}}}$ decreases in magnitude in the inner core region and increases significantly in the outer confined region, simultaneously contributing to preserving centrally peaked $\textrm{Fe}$ profiles and exhausting the impurities. The ${D_{\textrm{Fe}}}$ and ${\nu _{\textrm{Fe}}}$ variations lead to reduced impurity contents in the plasma. The three-dimensional edge impurity transport code EMC3-EIRENE was also applied for a case of RMP-mitigated high-Z accumulation at EAST and compared to that of low-Z carbon. The exhaust of ${\textrm{C}^{6 + }}$ toward the scrape-off layer accompanying an overall suppression of heavier ${\textrm{W}^{30 + }}$ is observed when using RMPs.

A one-dimensional steady-state model for stimulated Raman backscatter (SRS) and stimulated Brillouin backscatter (SBS) processes in laser-irradiated plasmas is presented. Based on a novel “predictor-corrector” method, the model is capable to deal with broadband scattered light and inhomogeneous plasmas, exhibiting robustness and high efficiency. Influences of the electron density and temperature on the linear gains of both SRS and SBS are investigated, which indicates that the SRS gain is more sensitive to the electron density and temperature than that of the SBS. For the low-density case, the SBS dominates the scattering process, while the SRS exhibits much higher reflectivity in the high-density case. The nonlinear saturation mechanisms and competition between SRS and SBS are included in our model by a phenomenological method. The typical anti-correlation between SRS and SBS versus electron density is reproduced in the model. Calculations of the reflectivities are qualitatively in agreement with the typical results of experiments and simulations.

Sample geometry effects on mechanical strengths of gold micro-cantilevers are evaluated by a micro-bending test. Six micro-cantilevers with the same length of 50 μm are prepared, and the width and the thickness are varied to examine individual effects on the yield stress. The yield stress increases from 428 to 519 MPa when the thickness decreases from 11.1 to 6.0 μm. No obvious dependency is observed when varying the width. The results reveal that the thickness and the width each has a different influence on the yield stresses of micro-cantilevers evaluated by the bending test, which is the sample geometry effect.

We conduct numerical simulations to investigate the formation and evolution of drops and vortex rings of particle-laden fingers in double-diffusive convection in stably stratified environments. We show that the temporal evolution can be divided into double diffusion, acceleration and deceleration phases. The acceleration phase is a result of the vanishing temperature perturbation in the drop during the descent in the layer of uniform temperature. The drop decelerates because it transforms into a vortex ring. A theoretical drag model is presented to predict the speed of the spherical drop with the low drop Reynolds number. By formulating the boundary condition based on the vorticity, our drag model gives a more general form of the drag coefficient for small spherical drops and shows good agreement in predicting the drag coefficient. Drops with five particle sizes are compared, and it is found that although the greater vertical settling enhances vertical transport, the final state differs little among the various sizes. Comparison of our drag model with the simulation results under various bulk conditions and previous experimental results shows good model predictability. Finally, a comparison with the salt-finger case shows that the diffusive nature of the dissolved scalar field, along with the wake effect, can result in an apparent loss of mass from the drop and a permanent presence of the connection between the drop and its parent finger. This makes the observed detachment of the particle-laden drop much less likely in the salt-finger case.

As a wide-reaching institutional reform, China's fiscal decentralization was launched in the early 1980s to encourage provincial economic growth by granting more financial autonomy to provincial governments. In this paper, the impact of fiscal decentralization on China's environmental quality is investigated both theoretically and empirically. A neoclassical model is developed based on the primary characteristics of China's fiscal decentralization. Using provincial panel data for the period 1995-2015, a two-equation regression model is employed to empirically verify the three propositions of the theoretical model: (1) there exists an inverted-U shaped relationship between fiscal decentralization and GDP per capita; (2) fiscal decentralization is positively related to GDP per capita at the steady state; (3) there is an inverted-U shaped Environmental Kuznets Curve relationship between pollution emissions and economic growth.

The elastic polymer composite embedded with carbon nanotubes (CNTs) is an ideal candidate for stretchable and flexible sensor fabrication due to the perfect combination between the excellent properties of CNTs and the high stretchability of the elastomer. A cube model of nanotube/polymer composite is constructed to comprehensively and theoretically analyze its electrical behavior, which is dominantly governed by the CNT network. The aspect ratio and alignment of CNTs significantly influence both the percolation threshold range and the electrical conductivity; however, the electrical conductivity of CNTs has little impact on the percolation threshold. The piezoresistivity of the composite is not only governed by the property of CNTs but also by the mechanical property of the polymer matrix, including the Poisson’s ratio and alignment of CNTs. The specific reasons why the composite resistance rises when it is stretched are investigated. Finally, one optimizing suggestion is given for making the CNTs/polymer composite with high sensitivity.

Several studies have suggested that higher carotenoid levels may be beneficial for atherosclerosis patients, but few studies have examined this relationship in the Chinese population. This cross-sectional study examined the association between the levels of carotenoids in diet and serum and carotid intima–media thickness (IMT) in Chinese adults aged 50–75 years in Guangzhou, China. Dietary intake was assessed using a FFQ. HPLC was used to assay the serum concentrations of α-carotene, β-carotene, lutein+zeaxanthin, β-cryptoxanthin and lycopene. The IMT at the common carotid artery (CCA) and bifurcation of the carotid artery was measured by B-mode ultrasound. A total of 3707 and 2947 participants were included in the analyses of dietary and serum carotenoids. After adjustment for demographic, socio-economic and lifestyle factors, all the serum carotenoids levels except lycopene were found to be inversely associated with the IMT at the CCA and bifurcation (Ptrend<0·001 to 0·013) in both men and women. The absolute mean differences in the IMT between the subjects in the extreme quartiles of serum carotenoid levels were 0·034 mm (α-carotene), 0·037 mm (β-carotene), 0·032 mm (lutein+zeaxanthin), 0·030 mm (β-cryptoxanthin), 0·015 mm (lycopene) and 0·035 mm (total carotenoids) at the CCA; the corresponding values were 0·025, 0·053 0·043, 0·050, 0·011 and 0·042 mm at the bifurcation. The favourable associations were also observed between dietary carotenoids (except lycopene) and the CCA IMT. In conclusion, elevated carotenoid levels in diet and serum are associated with lower carotid IMT values (particular at the CCA) in Chinese adults.

The hydrobaric effect on photoactivity of titanium dioxide (TiO2) fabricated by cathodic deposition in an aqueous solution was evaluated in this study. When the applied pressure was increased to 35 MPa, the water-splitting performance was improved by almost fourfold of the performance of the TiO2 prepared at atmospheric pressure. The surface states effect was significant in the deposited TiO2, which was exploited to affect the charges recombination of TiO2, and thereby enhance the resultant photoelectrochemical water-splitting performance. The hydrobaric cathodic deposition could be extended to fabrication of other metal oxides to eliminate the negative influence from the high-temperature process.

In traditional antenna design, metal components are not placed in the central part of the antenna as they change the characteristics of near field radiation. However, we show that placing a metal ring in the centre of the strip lines, which connect the ends of folded high-frequency dipoles, does not damage the performance of the feed. Instead it significantly improves the voltage standing wave ratio of the feed whilst other performance indicators are not compromised. Thus, our findings show an excellent way of improving the wide band feed. Based on this foundation, a new circularly polarised feed for operation between 0.4 to 2 GHz is introduced for the Chinese Spectral Radioheliograph in this paper. The issue of a feed impedance matching network is investigated. By optimising the impedance matching, the performance of the feed is enhanced with respect to the previous realisations of the Eleven feed. The simulation and experimental results show that the gain of the feed is about 10 dBi, and the VSWR is less than 2:1. In addition, the feed has a low axial ratio, fixed phase centre location, and constant beam width in the range of 0.4 to 2 GHz.

This study investigated the influences of neighborhood factors (residential stability and neighborhood disadvantage) and variants of the serotonin transporter linked polymorphic region (5-HTTLPR) genotype on the development of substance use among African American children aged 10–24 years. To accomplish this, a harmonized data set of five longitudinal studies was created via pooling overlapping age cohorts to establish a database with 2,689 children and 12,474 data points to span ages 10–24 years. A description of steps used in the development of the harmonized data set is provided, including how issues such as the measurement equivalence of constructs were addressed. A sequence of multilevel models was specified to evaluate Gene × Environment effects on growth of substance use across time. Findings indicated that residential instability was associated with higher levels and a steeper gradient of growth in substance use across time. The inclusion of the 5-HTTLPR genotype provided greater precision to the relationships in that higher residential instability, in conjunction with the risk variant of 5-HTTLPR (i.e., the short allele), was associated with the highest level and steepest gradient of growth in substance use across ages 10–24 years. The findings demonstrated how the creation of a harmonized data set increased statistical power to test Gene × Environment interactions for an under studied sample.

The Chinese Spectral Radioheliograph is an aperture-synthesis telescope observing the Sun in ultra wide bandwidth on the ground. It contains two arrays Chinese Spectral Radioheliograph-I and Chinese Spectral Radioheliograph-II from 0.4 to 15 GHz. In order to obtain ultra wide-band performance, the cascaded folded dipoles are used in this feed. At the same time, in order to get circularly polarised signals coming from the Sun, a wide-band 90° hybrid is added in the output ports of the feed. This feed has characteristics of about 10 dBi gain, less than 1.5 voltage standing wave ratio. It also has characteristics with low axial ratio, fixed phase centre location, and constant beam width in operating frequencies. Through cross-correlating all combinations of two orthogonal polarisations at each antenna, the polarisation state of the waves is measured and give a differential instrumental delay between two data channels. The relationship between the own polarisation degree of the Sun and the observed polarisation degree is also measured for cross-polarised delay in observing the Sun in this paper.

This study was designed to examine the prospective relations of life stress and genetic status with increases in drug use. African Americans (N = 399) in rural Georgia (Wave 1 mean age = 17 years) provided three waves of data across 27.5 months and a saliva sample from which the dopamine receptor D4 (DRD4) gene was genotyped. Multilevel growth curve modeling analysis indicated that emerging adults manifested the highest escalations in drug use when they reported high life stress and carried an allele of DRD4 with 7 or more repeats (7 + R allele). In addition, emerging adults who reported high life stress and carried the 7 + R allele evinced the largest increases in two proximal risk factors for drug use: affiliations with drug-using companions and drug use vulnerability cognitions. Furthermore, when the Gene × Environment interaction effects on the increases in affiliations with drug-using companions and vulnerability cognitions were entered into the model forecasting drug use, the Life Stress × DRD4 Status interaction on drug use became nonsignificant in the presence of the risk mechanisms. This finding provides an example of “second generation” Gene × Environment interaction research in which the interaction's effects on proximal risk mechanisms account for its effects on outcomes.

This study examined the prospective relations of adolescents' perceptions of discrimination and their genetic status with increases in conduct problems. Participants were 461 African American youths residing in rural Georgia (Wave 1 mean age = 15.5 years) who provided three waves of data and a saliva sample from which a polymorphism in the SCL6A4 (serotonin transporter [5-HTT]) gene polymorphism known as the 5-HTT linked promoter region (5-HTTLPR) was genotyped. Data analyses using growth curve modeling indicated that perceived discrimination was significantly related to the slope of conduct problems. As hypothesized, interactions between perceived discrimination and genetic status emerged for male but not female youths. Compared with those carrying two copies of the long allele variant of 5-HTTLPR, male youths carrying one or two copies of its short allele variant evinced higher rates of conduct problems over time when they perceived high levels of racial discrimination. These findings are consistent with resilience and differential susceptibility propositions stating that genes can both foster sensitivity to adverse events and confer protection from those events.

The Chelonia face an extinction crisis, particularly in Asia: unsustainable harvests, and habitat fragmentation and loss accompanying rapid urbanization and land development all pose threats to turtles. These threats are particularly acute for those species with a high commercial value such as the yellow-margined box turtle Cuora flavomarginata. Because of burgeoning demand in the food and pet markets, combined with extensive habitat loss, C. flavomarginata is categorized as Endangered on the IUCN Red List. To investigate the status and distribution of this species in Taiwan we conducted an extensive trapping survey in 2001–2008, locating a total of 527 different individuals at 23 sites. Our results show that C. flavomarginata is restricted to low-elevation forested hills. Populations in lowland areas may have been extirpated by land development. There are four clusters of localities in low-elevation primary and secondary forests, and some relatively large populations survive. However, capture success at most sites was low. In those sites where we trapped > 20 individuals, sex ratios were significantly skewed towards females and adults predominated. The most essential measure for the conservation of C. flavomarginata in Taiwan is to secure and preserve some relatively undisturbed habitats at low elevations.

A three-wave cascade model linking life stress to increases in risk behavior was tested with 347 African American emerging adults living in the rural South. Data analyses using structural equation modeling and latent growth curve modeling demonstrated that life stress was linked to increases in risk behavior as African Americans transitioned out of secondary school. The cascade model indicated that life stress fostered increases in negative emotions. Negative emotions, in turn, were linked to increases in affiliations with deviant peers and romantic partners; this forecast increases in risk behavior. The findings supported a stress proliferation framework, in which primary stressors affect increases in secondary stressors that carry forward to influence changes in risk behaviors that can potentially compromise mental health.

In this study we report on the correlation between the bacteriology of the middle meatusand ethmoid sinus in chronic sinusitis. When patients with chronic sinusitis underwent functional endoscopicsinus surgery (FESS), swab specimens were taken from the middle meati before surgery. After removing the ethmoid bullae, swab specimens were taken from the ethmoid sinuses. Between November 1998 and February 2001, 186 pairs of middle meatal and ethmoid sinus specimens were collected from 186 patients. No bacteria were cultured from either specimen in 32 patients. The same bacteria were cultured from both specimens in another 60 patients. The culture results differed between the middle meatal and ethmoid sinus specimens in the remaining 94 patients. There was a significant difference between culture rates of 63.4 per cent for middle meatal specimens and 76.3 per cent for the ethmoid sinus specimens. In analysing bacterial species, significantly more aerobic Gram negative bacteria were cultured from the ethmoid sinus specimens than from the middle meatalspecimens. This study shows that the bacteriology of the middle meatus was different from that of the ethmoid sinus. Therefore, the bacteriological findings in the middle meati may not reflect the real bacteriology in chronic sinusitis.