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The X-ray emissions in the interaction of 3–6 MeV Xe23+ ions into thick solid In target are measured. The projectile-to-target and target Lα/Lβ X-ray production intensity ratios are observed to strongly depend on the projectile energy. The dependence deviates from Coulomb ionization predictions, which implies the important roles of coupling between subshells and the activation of 4fσ rotational couplings for projectile energy larger than 5 MeV.
This study attempts to figure out the seasonality of the transmissibility of hand, foot and mouth disease (HFMD). A mathematical model was established to calculate the transmissibility based on the reported data for HFMD in Xiamen City, China from 2014 to 2018. The transmissibility was measured by effective reproduction number (Reff) in order to evaluate the seasonal characteristics of HFMD. A total of 43 659 HFMD cases were reported in Xiamen, for the period 2014 to 2018. The median of annual incidence was 221.87 per 100 000 persons (range: 167.98/100,000–283.34/100 000). The reported data had a great fitting effect with the model (R2 = 0.9212, P < 0.0001), it has been shown that there are two epidemic peaks of HFMD in Xiamen every year. Both incidence and effective reproduction number had seasonal characteristics. The peak of incidence, 1–2 months later than the effective reproduction number, occurred in Summer and Autumn, that is, June and October each year. Both the incidence and transmissibility of HFMD have obvious seasonal characteristics, and two annual epidemic peaks as well. The peak of incidence is 1–2 months later than Reff.
The third generation of the BeiDou navigation satellite system (BDS-3) is a global navigation system, and is expected to be in full operation by 2020. High-precision orbits are a precondition for BDS-3 to provide a highly accurate service, which needs a global tracking and monitoring capability for the operational satellites. However, it is difficult for BDS to construct global ground monitoring stations. Fortunately, Ka-band Inter-Satellite Link (ISL) antennae fitted to the BDS-3 satellites can be used to extend the visible arc of the Medium Earth Orbit (MEO) satellites and to enhance the ground stations for orbit determination. This paper analyses the ISL-enhanced orbit determination for eight BDS-3 satellites, using the data from ten Chinese domestic stations and 13 international Global Navigation Satellite System (GNSS) Monitoring and Assessment System (iGMAS) overseas stations. The results show that the Three-Dimensional (3D) position Root Mean Square (RMS) error of the Overlapping Orbit Differences (OODs) is approximately 1 m when only ten regional stations are used. When the ISL measurements are added, the 3D position RMS error is decreased to 0·5 m, and the accuracy of the 24-hour orbit prediction can also be improved from 2 m to 0·7 m, which is even better than that of the orbits determined using globally distributed stations. It can be expected that with the subsequent launch of BDS-3 satellites and the increasing number of ISLs, the advantage of the ISL enhanced orbit determination will become more significant.
Associations have been shown between father’s absence and menarcheal age, but most studies have focused on absence resulting from divorce, abandonment or death. Little research has been conducted to evaluate the effect on menarcheal age of paternal absence through migrant work. In a sample of 400 middle school students, this study examined the association between paternal migrant work and menarcheal age against a backdrop of extensive rural-to-urban migration in China. Data were collected through a self-reported questionnaire, including social-demographic characteristics, aspects of family relationships, information about father’s migrant work and age at menarche. After adjusting for BMI, parent marital status and perceived relationship with mother, lower self-perceived quality of father–daughter relationship (both ‘father present, relationship poor’ and ‘father absent, relationship poor’) and lower frequency of contact with the father were associated with higher odds for early menarche. These findings suggest that the assumption that father’s absence for work influences the timing of menarche needs to be examined in the context of the quality of the father–daughter relationship and paternal care, which appear to play a critical role in the timing of menarche. These findings also emphasize the importance of enhancing paternal involvement and improving father–daughter relationships in the development of appropriate reproductive strategy in daughters.
Wireless power transmission (WPT) systems with moveable mechanical parts have been acquired more and more attention during the past decade. However, due to the moveable feature of transmitting coil and receiving coil, misalignment issue lead to extra power loss, decrease in efficiency, increase in control complexity, and unwanted performance degradation of the whole system. Moreover, it happened frequently than those traditional planar coils systems. The motivation for this paper is trying to have a deep understanding of quantitative relationship between ball-shaped coils mutual inductance and misalignment. Based upon that, engineers would know more detail of the coils position and mutual inductance. So, optimized design might be achieved. On considering that, this paper presents a WPT system with a ball-shaped coil for robot joints. A mutual inductance calculation based on filament method aimed at ball-shaped coil is proposed. Based on these, nine different ball-shaped coil solutions are calculated. Then, model with a minimized change rate of mutual inductance against the angular misalignment is chosen as the optimized design. Circuit analysis of the WPT system with the series–series resonant topology is conducted to choose a proper working frequency and load. Finally, an experimental platform is established. It demonstrates the feasibility of the proposed calculation method and the feasibility of the WPT prototype.
Heavy metal contamination in the paddy soils of China is a serious concern because of its health risk through transfer in food chains. A field experiment was conducted in 2014–2015 to investigate the long-term effects of different biochar amendments on cadmium (Cd) and arsenic (As) immobilisation in a contaminated paddy field in southern China. Two types of biochar, a rice-straw-derived biochar (RB) and a coconut-by-product-derived biochar (CB), were amended separately to determine their impacts on rice yield and their efficacy in reducing Cd and As in rice. The two-year field experiment showed that biochar amendments significantly improved the rice yields and that CB is superior to RB, especially in the first growth season. Using a large amount of biochar amendment (22.5tha–1) significantly increased soil pH and total organic carbon, and concomitantly decreased the Cd content in rice grains over the four growth seasons, regardless of biochar type and application rate. Arsenic levels in rice were similar to the control, and results from this study suggest that there was a sustainable effect of biochar on Cd sequestration in soil and reduction of Cd accumulation in rice for at least two years. Biochar amendment in soil could be considered as a sustainable, reliable and cost-effective option to remediate heavy metal contamination in paddy fields for long periods.
The 2Cr13/316L multilayered composite plates were fabricated by hot rolling with recycle heating step. The effect of rolling reductions on microstructure and properties was investigated. The 2Cr13 layer consists of martensite and lath ferrite, but the middle layer has less ferrite than both sides. The content and grains of ferrite increase with the increase of the reduction and number of reheating, which leads to a decrease in the hardness of the 2Cr13 layer. The hardness of the 2Cr13 layer is determined by the volume ratio of martensite and ferrite. Tensile strength of the specimens with the rolling reduction of 72% and 82% reached 815.8 MPa and 763.4 MPa, while elongations were 20% and 20.8%, respectively. With the increase of the rolling reduction, the fracture mode also changed from cleavage fracture to dimple fracture. There were no cracks and delamination when the 2Cr13/316L composite plate bent to 130° and 180°, which indicated better interfacial bonding.
The Beidou System (BDS) started functioning at the end of 2012. The Yaw-Steering (YS) attitude mode for Inclined Geosynchronous Orbit (IGSO) and Medium Earth Orbit (MEO) satellites in BDS ensures that the solar panels face the Sun. The orbit radial accuracies for IGSO/MEO satellites are 0·5 m and the User Equivalent Range Errors (UERE) are 1·5 m in YS mode. BDS-2 satellites adopt Orbit-Normal (ON) mode to meet the power supply and thermal control requirements of the satellite during deep Earth eclipse periods. In ON mode, long-term orbit ephemeris accuracy monitoring in the Operational Control System (OCS) of BDS indicates that the orbit accuracies for IGSO/MEOs are reduced to a few hundreds of metres, seriously affecting the positioning accuracy and navigation service capability of the BDS system. Solar Radiation Pressure (SRP) is difficult to model in ON mode. Continuous Yaw-Steering (CYS) mode is available for new generation Beidou satellites launched since 2015. The orbit accuracies for these new generation Beidou (BDS-3) satellites were estimated based on BDS monitoring station data and SRP models including ECOM 9/5/3. The evaluation method consisted of four steps, namely, orbit internal consistency analysis, UERE calculation, Satellite Laser Ranging (SLR) data fitting Root Mean Square (RMS) determinations and positioning performance analysis; the data gathering period lasted for more than 60 days and included two CYS periods and one ON period. The experiments showed that the orbit accuracy of the radial component in CYS mode for the BDS-3 satellites degrades by 2 to 3 cm and positioning accuracy degrades only by 1 cm over that in YS mode which is just a small reduction in accuracy compared with the decimetre-level BDS orbit accuracy and the metre-level single point positioning accuracy with BDS pseudorange data. This overcomes declining orbit and positioning accuracy issues in ON mode for BDS-2 satellites. Other results also show that the reliability of BDS has been improved.
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.
A new band-reject frequency-selective surface (FSS) based on dual-band near-zero refractive index metamaterial (ZIM) design is presented in this paper. Consisting of a planar array of complementary dual-layer symmetry resonant ring, the proposed FSS exhibits a high-selective band-reject filtering response. From the viewpoint of effective medium, the subwavelength FSS is characterized by near-zero effective magnetic permeability and near-zero effective electric permittivity in two different operational bands, respectively. The corresponding resonant behavior and E-field distributions are analyzed in detail. A prototype of the proposed FSS working in X-band is fabricated and measured. The simulation and experiment results verify the effectiveness and correctness of the ZIM-based design method.
This study aimed to describe the expression profiles of microRNAs (miRNAs) from mammary gland tissues collected from dairy cows with Streptococcus agalactiae-induced mastitis and to identify differentially expressed miRNAs related to mastitis. The mammary glands of Chinese Holstein cows were challenged with Streptococcus agalactiae to induce mastitis. Small RNAs were isolated from the mammary tissues of the test and control groups and then sequenced using the Solexa sequencing technology to construct two small RNA libraries. Potential target genes of these differentially expressed miRNAs were predicted using the RNAhybrid software, and KEGG pathways associated with these genes were analysed. A total of 18 555 913 and 20 847 000 effective reads were obtained from the test and control groups, respectively. In total, 373 known and 399 novel miRNAs were detected in the test group, and 358 known and 232 novel miRNAs were uncovered in the control group. A total of 35 differentially expressed miRNAs were identified in the test group compared to the control group, including 10 up-regulated miRNAs and 25 down-regulated miRNAs. Of these miRNAs, miR-223 exhibited the highest degree of up-regulation with an approximately 3-fold increase in expression, whereas miR-26a exhibited the most decreased expression level (more than 2-fold). The RNAhybrid software predicted 18 801 genes as potential targets of these 35 miRNAs. Furthermore, several immune response and signal transduction pathways, including the RIG-I-like receptor signalling pathway, cytosolic DNA sensing pathway and Notch signal pathway, were enriched in these predicted targets. In summary, this study provided experimental evidence for the mechanism underlying the regulation of bovine mastitis by miRNAs and showed that miRNAs might be involved in signal pathways during S. agalactiae-induced mastitis.
Objectives: Mental arithmetic is essential to daily life. Researchers have explored the mechanisms that underlie mental arithmetic. Whether mental arithmetic fact retrieval is dependent on surface modality or knowledge format is still highly debated. Chinese individuals typically use a procedure strategy for addition; and they typically use a rote verbal strategy for multiplication. This provides a way to examine the effect of surface modality on different arithmetic operations. Methods: We used a series of neuropsychological tests (i.e., general cognitive, language processing, numerical processing, addition, and multiplication in visual and auditory conditions) for a patient who had experienced a left frontotemporal stroke. Results: The patient had language production impairment; but preserved verbal processing concerning basic numerical abilities. Moreover, the patient had preserved multiplication in the auditory presentation rather than in the visual presentation. The patient suffered from impairments in an addition task, regardless of visual or auditory presentation. Conclusions: The findings suggest that mental multiplication could be characterized as a form of modality-dependent processing, which was accessed through auditory input. The learning strategy of multiplication table recitation could shape the verbal memory of multiplication leading to persistence of the auditory module. (JINS, 2017, 23, 692–699)
Researches have suggested Mediterranean diet might lower the risk of chronic diseases, but data on skeletal muscle mass (SMM) are limited. This community-based cross-sectional study examined the association between the alternate Mediterranean diet score (aMDS) and SMM in 2230 females and 1059 males aged 40–75 years in Guangzhou, China. General information and habitual dietary information were assessed in face-to-face interviews conducted during 2008–2010 and 3 years later. The aMDS was calculated by summing the dichotomous points for the items of higher intakes of whole grain, vegetables, fruits, legumes, nuts, fish and ratio of MUFA:SFA, lower red meat and moderate ethanol consumption. The SMM of the whole body, limbs, arms and legs were measured using dual-energy X-ray absorptiometry during 2011–2013. After adjusting for potential covariates, higher aMDS was positively associated with skeletal muscle mass index (SMI, SMM/height2, kg/m2) at all of the studied sites in males (all Ptrend<0·05). The multiple covariate-adjusted SMI means were 2·70 % (whole body), 2·65 % (limbs), 2·50 % (arms) and 2·70 % (legs) higher in the high (v. low) category aMDS in males (all P<0·05). In females, the corresponding values were 1·35 % (Ptrend=0·03), 1·05, 0·52 and 1·20 %, (Ptrend>0·05). Age-stratified analyses showed that the favourable associations tended to be more pronounced in the younger subjects aged less than the medians of 59·2 and 62·2 years in females and males (Pinteraction>0·10). In conclusion, the aMDS shows protective associations with SMM in Chinese adults, particularly in male and younger subjects.
In this paper, we present some efficient numerical schemes to solve a two-phase hydrodynamics coupled phase field model with moving contact line boundary conditions. The model is a nonlinear coupling system, which consists the Navier-Stokes equations with the general Navier Boundary conditions or degenerated Navier Boundary conditions, and the Allen-Cahn type phase field equations with dynamical contact line boundary condition or static contact line boundary condition. The proposed schemes are linear and unconditionally energy stable, where the energy stabilities are proved rigorously. Various numerical tests are performed to show the accuracy and efficiency thereafter.