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Globally, China is among the ‘saltiest’ nations. In order to support current nationwide salt reduction initiatives, we investigated Chinese consumers’ knowledge, beliefs and behaviours related to salt intake and salt reduction.
A cross-sectional face-to-face survey was carried out, focusing on salt knowledge, beliefs and behaviours related to salt intake and salt reduction, perceptions of salt reduction responsibility and support for different national strategies.
The survey was carried out in China mainland.
Consumers (n 2444) from six of seven major geographical regions in China participated in the survey. After data cleaning, a sample of 2430 was included in the final analysis.
A majority of Chinese consumers believed that salt added during home cooking was the biggest contributor to their salt intake. Knowledge gaps existed in the awareness of salt hidden in certain foods and flavouring products. Chinese consumers in general were interested in lowering their salt intake. They were aware of salt reduction tools, but the adoption level was low. Consumers expressed strong support for promotion of salt-restriction spoons and public education, but not fiscal policies (e.g. salt-related tax or subsidies). In terms of individual differences, education status demonstrated a substantial impact on salt reduction knowledge and behaviour.
There is still big room to ‘shake’ Chinese consumers’ salt habit. The present study provides important evidence and consumer insights to support China’s efforts to meet its salt reduction targets.
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.
Since the ‘Grain to Green Program' was launched in 1999 in the Loess Plateau, China, the processes and patterns of ecological change have become important. Through the use of the fractional vegetation cover (FVC) index, this study examines the spatial distribution and temporal change of vegetation cover in the Loess Plateau during 2000–2014. Over this period more than 60% of the Loess Plateau has remained with little vegetation cover (FVC <30%). The spatial distribution pattern shows an overall increase from the NW to SE. Temporally, the vegetation cover exhibits a general trend of improvement. In 2000–2005, 2000–2010 and 2000–2014, the percentages of restored vegetation (vegetation with significantly increased FVC, P<0.05) were 2, 21 and 52%, respectively. The rate of vegetation cover restoration was highly variable among different bioclimatic zones. The expansion of restored vegetation was greater in the N of the Loess Plateau than in the south. Both human restoration activities and climatic fluctuation influenced the vegetation cover change. The ‘Grain to Green Program' emphasised vegetation restoration. Regional precipitation also had clear effects on vegetation cover. The results of this study reveal that vegetation change shows a non-linear process in response to climate and ecological restoration measures, and that the change gradually emerges over time. This study highlights the importance of considering the spatiotemporal variability in vegetation cover during the implementation of restoration programs, which could aid decision-making for the effective and sustainable management of large-scale restoration programs.
The addition of vegetable to carbohydrate-based meals was shown to contribute to glycaemic management. The aim of this study was to investigate the impact of homogenisation on vegetables added to rice meals in terms of acute glycaemic responses (GR). In a randomised crossover trial, sixteen healthy volunteers completed thirteen test sessions, which included two sessions for glucose control, two for rice and nine for different vegetable-rice mixed meals: cooked pak choi and cooked rice (CP+R); cooked cauliflower and cooked rice (CC+R); cooked eggplant and cooked rice (CE+R); and their homogenised counterparts, both raw or cooked. Postprandial GR tests, in vitro carbohydrate digestion and chemical analyses were carried out for each test meal. Compared with pure rice, CE+R, CP+R and CC+R meals achieved significantly lower glycaemic indexes (GI) of 67, 71 and 73, whereas their homogenised counterparts failed to show significant difference with rice. The hydrolysis indexes (HI) of CE+R, CP+R and CC+R were 69·6, 83·8 and 80·6 % of the HI of the rice control. CE had the greatest effect on lowering the GI, the incremental area under the blood glucose curve from 0 to 120 min, the peak glucose value, the maximum amplitude of glucose excursion in 0–120 min (MAGE0–120), the HI and rapid available starch. Both in vitro and in vivo tests demonstrated that incorporating non-homogenised cooked vegetables into a rice meal could slow the carbohydrate digestion and improve postprandial GR. Texture properties of vegetable may play an important role in underlying glycaemic control mechanisms.
A novel synthetic air data estimation method without using air data sensors is presented, and the method only relies on the information from the Navigation System (NS) and Flight Control System (FCS). The aircraft's aerodynamic model is also required to make a connection between the FCS control parameters and the NS measurements. The airspeed, angle of attack and sideslip, angular velocity and wind speed are defined as state vectors, and state equations are established through the aircraft's aerodynamic model and dynamics. Linear velocity and angular velocity provided by the navigation system are considered as the measurement vector. To deal with variable wind fields, a novel Initialised Three-step Extended Kalman Filter (ITEKF), which considers the wind speed as an unknown input, is developed to track the variation of wind speed. Simulation results based on a Generic Hypersonic Vehicle (GHV) model are presented and compared with an existing method. Factors affecting the method's accuracy include the navigation system accuracy and the aerodynamic model error, are also discussed.
Parents commonly fail to correctly recognize the weight status of their child. Whether parental perception of child weight is associated with weight-related parenting behaviours and child behaviours is unclear. The present study aimed to investigate the distribution of parental perception of child weight and its associations with weight-related parenting behaviours and child behaviours in China.
Seven provinces in China.
A total of 47 417 children aged 6–17 years and their parents were included from a national survey in 2013. Parental perception of child weight, weight-related parenting behaviours and child behaviours were self-reported. Child’s weight and height were objectively measured.
A total of 30·5 % of parents underestimated and 8·7 % overestimated the child’s weight. Parental underestimation was more common among younger children, boys and children with a lower BMI Z-score. Parents who perceived that their child had a healthy weight (accurately or inaccurately) were more likely to prepare breakfast for the child, exercise with him/her, set apart his/her exercise time, restrict his/her screen time, and were less likely to store soft drinks for the child. Children perceived to have a healthy weight, regardless of their actual weight status, behaved healthier on dietary intake, physical activity and homework time.
Parental underestimation of their child’s weight was prominent in China, especially among younger children, boys and children with a lower BMI Z-score. Parental recognition of their child being overweight did not appear to translate into healthy changes in weight-related parenting behaviours or child behaviours.
We report a novel tip-type field emission (FE) emitter by synthesizing the few-layer graphene (FLG) flakes on tip of nichrome (8020) wire (ϕ≈80 μm) by microwave plasma enhanced chemical vapor deposition(PECVD). These resultant random arrays of free-standing FLG flakes are aligned vertically to the substrate surface in a high-density and stacked to each other to form several larger “flower-like” agglomerates in spherical shapes. The FE performance of the tip-type FLG flakes emitter shows a low threshold field of 0.55 V/μm, a large field enhancement factor of 9455 ± 46, a large field emission current density of 22.18 A/cm2 at 2.70 V/μm, and an excellent field emission stability at high emission current densities (6.93 A/cm2). It can be used in variety of applications that include cathode-ray tube monitors, X-ray sources, electron microscopes, and other vacuum electronic applications.
Experimental and numerical investigations on the interaction of a planar shock wave with two-dimensional (2-D) and three-dimensional (3-D) light gas cylinders are performed. The effects of initial interface curvature on flow morphology, wave pattern, vorticity distribution and interface movement are emphasized. In experiments, a wire-restriction method based on the soap film technique is employed to generate N
cylinders surrounded by SF
with well-characterized shapes, including a convex cylinder, a concave cylinder with a minimum-surface feature and a 2-D cylinder. The high-speed schlieren pictures demonstrate that fewer disturbance waves exist in the flow field and the evolving interfaces develop in a more symmetrical way relative to previous studies. By combining the high-order weighted essentially non-oscillatory construction with the double-flux scheme, numerical simulation is conducted to explore the detailed 3-D flow structures. It is indicated that the shape and the size of 3-D gas cylinders in different planes along the vertical direction change gradually due to the existence of both horizontal and vertical velocities of the flow. At very early stages, pressure oscillations in the vicinity of evolving interfaces induced by complex waves contribute much to the deformation of the 3-D gas cylinders. As time proceeds, the development of the shocked volume would be dominated by the baroclinic vorticity deposited on the interface. In comparison with the 2-D case, the oppositely (or identically) signed principal curvatures of the concave (or convex) SF
boundary cause complex high pressure zones and additional vorticity deposition, and the upstream interface from the symmetric slice of the concave (or convex) N
cylinder moves with an inhibition (or a promotion). Finally, a generalized 3-D theoretical model is proposed for predicting the upstream interface movements of different gas cylinders and the present experimental and numerical findings are well predicted.
The Lorentz factor (Γ) is an important parameter related to the relativistic jet physics. We study the evolution patterns of Γ within gamma-ray burst (GRB) and active galactic nuclear jets for individual GRB 090168, GRB 140508A, and 3C 454.3. By estimating the Γ values for well-separated pulses in GRBs 090618 and 140508A with an empirical relation derived from typical GRBs, we find that the Γ evolution pattern in the two GRBs are different. The increasing-to-coasting evolution pattern of Γ in GRB 090618 likely indicates that the GRB fireball is still being accelerated in the prompt phase. The clear decrease evolution pattern of Γ in GRB 140508A suggests the deceleration of the fireball components. By deriving the Γ value through fitting their spectral energy distribution in different flares of 3C 454.3, a pattern of Γ-tracking-γ-ray flux is clearly found, likely indicating that the observed gamma-ray flares are being due to the Doppler boosting effect to the jet emission.
The present study was performed to identify the genotype of a hypertrophic cardiomyopathy family and investigate the clinicopathogenic characteristics and prognostic features of relevant genetic abnormalities. Target sequence capture sequencing was performed to screen for pathogenic alleles in a 32-year-old female patient (proband). Sanger sequencing was carried out to verify the results. Sanger sequencing was also performed on other family members to identify allele carriers. A survival analysis was carried out using published literature and our findings. We found that the proband and her son harboured a Gly716Arg sequence variant of the β-myosin heavy chain. Neither the proband’s father nor the mother were carriers of this sequence variant; thus, the mutation was classified as “de novo”. Further survival analysis revealed that female patients appear to have a longer life expectancy compared with males. Our study may provide an effective approach for the genetic diagnosis of hypertrophic cardiomyopathy.
Recently, there has been a significant increase in the rate of multiple births in most developed countries. However, few population-based studies have been conducted in China regarding the epidemiology of twin births in recent years. We performed a descriptive analysis of twin births from 1993 to 2005 using data from a population-based perinatal care program in southeast China. The twin birth rate in southeast China was 0.65%, and the twin birth rates from 1993 to 2005 fluctuated between 0.60% and 0.70%. During the three periods of 1993–1996, 1997–2000, and 2001–2005, the twin birth rate increased from 0.57% to 0.71% in urban areas (p = .005) and from 0.59% to 0.68% in mothers who had an education level of high school or higher (p = .046). After 2000, the twin birth rate of primiparae 30 years of age and older significantly increased from 0.72% to greater than 1.20%. We concluded that the twin birth rates in southeast China from 1993 to 2005 stayed constant in the overall population but increased in certain subgroups of women, presumably due to increased use of fertility treatment and the development of assisted reproductive technology.
The present study evaluated the prebiotic effect of a standardised aqueous extract of Anoectochilus formosanus (SAEAF) and its effects on osteoporosis in ovariectomised (OVX) rats. The OVX rats were randomly divided into five groups and orally treated with water, SAEAF (200 and 400 mg/kg daily) and inulin (400 mg/kg daily) for 12 weeks. The sham group was orally treated with water. The SAEAF treatment enhanced the number of faecal bifidobacteria in OVX rats. The results of a Ca-balance experiment showed that SAEAF increased apparent Ca absorption and retention. The OVX rats were killed after SAEAF treatment lasting 12 weeks. The SAEAF decreased the caecal pH values and increased the caecal wall weight, caecal mucosa calbindin-D9k mRNA expression, free-Ca concentration and levels of SCFA in the caecum. The mineral content, density and biomechanical strength of bones were lower in OVX rats than the sham group, but these bone losses were prevented by SAEAF administration. Microtomography scanning showed that the SAEAF-treated rats had higher trabecular bone volume than the OVX rats. These results suggest that SAEAF prevented bone loss associated with ovarian hormone deficiency in the rats.
Dust is a crucial component of galaxies in modifying the observed properties of galaxies. Previous studies have suggested that dust reddening in star-forming galaxies is correlated with star formation rate (SFR), luminosity, gas-phase metallicity (Z), stellar mass (M*) and inclination. In this work we investigate the fundamental relations between dust reddening and physical properties of galaxies, and obtain a well-defined empirical recipe for dust reddening. The empirical formulae can be incorporated into semi-analytical models of galaxy formation and evolution to estimate the dust reddening and facilitate comparison with observations.
Research in non-volatile memories (NVM) has intensified in the past few years due to the ever increasing demand for information storage and the near ubiquity of handheld electronics. Resistive memory is a leading contender in this NVM market due to its high endurance, random accessibility, scalability and low programming voltage.
The addition of an external series resistor or imposing current compliance is often used to limit the current through RRAM devices and to prevent “over-programming” and stuck-at-one (SA1) errors. Here, we demonstrate that utilizing an external series resistor is not efficient in preventing over-programming and an on-chip resistor is more desirable.
Poly-silicon bottom electrode based devices (with the poly-silicon electrode acting like an on-chip resistor) and metal bottom electrode devices were fabricated and tested. The presence of the on-chip resistor is shown to enhance the endurance of the RRAM device. This technique of including an on-chip resistor prevents stored current discharge through the device as the device transitions from a high resistance to a low resistance state. A SPICE simulation is also employed to illustrate the benefit of this approach.
We have demonstrated and studied polymeric solid-state dye lasers (SSDLs) fabricated by three-dimensional (3D) polystyrene colloidal crystals and tert-butyl roadamine B (t-Bu RhB) doped Poly (methyl methacrylate) (PMMA) films with different film thickness. The sandwich-typed resonator cavities with different active layer thickness display single-mode lasing oscillations in the reflection bandgap of the colloidal crystals. The lasing thresholds could be optimized by changing the thickness of t-Bu RhB doped PMMA films, which is as low as 7.43 W/cm2. Adjusting active layer thickness would provide an opportunity to accelerate the development of fabricating polymeric SSDLs with low threshold.
Although conventional floating gate (FG) Flash memory has already gone into the sub-30 nm node, the technology challenges are formidable beyond 20nm. The fundamental challenges include FG interference, few-electron storage caused statistical fluctuation, poor short-channel effect, WL-WL breakdown, poor reliability, and edge effect sensitivity. Although charge-trapping (CT) devices have been proposed very early and studied for many years, these devices have not prevailed over FG Flash in the > 30nm node. However, beyond 20nm the advantage of CT devices may become more significant. Especially, due to the simpler structure and no need for charge storage isolation, CT is much more desirable than FG in 3D stackable Flash memory. Optimistically, 3D CT Flash memory may allow the Moore's law to continue for at least another decade. In this paper, we review the operation principles of CT devices and several variations such as MANOS and BE-SONOS. We will then discuss 3D memory architectures including the bit-cost scalable approach. Technology challenges and the poly-silicon thin film transistor (TFT) issues will be addressed in detail.
Bulk hybrid polymethyl methacrylate (PMMA)/SiO2 glass with Sb2S3 nanocrystals was prepared by the sol-gel process. We tried to minimize the quantity of water as much as possible in tetraethyl orthosilicate (TEOS) hydrolyzing, prepolymerized the organic monomers, mixed inorganic precursors, and prepolymerized organic monomers under a noncosolvent condition to reduce possible volume shrinkage. A silane coupling agent, which hydrolyzed simultaneously with TEOS, was introduced into the system to improve the miscibility of the organic and inorganic materials. The maximum dopant of Sb2S3 was 9 wt% in our experiments. The second-harmonic generation was observed in the hybrid PMMA/SiO2 glasses with electron-beam poling. Second-harmonic intensity increased with increase of accelerating voltage, current, and the content of Sb2S3 nanocrystals. The maximum χ2 in our study, as large as 1.64 p.m./V, was obtained under the optimized poling condition conducted at 25 kV, 20 nA, and 10 min. It was indicated from the thermally stimulated depolarization current measurements that the nonlinear layer was located in the thin 10-μm irradiated surface of the glass.
500 nm-thick aluminum-doped zinc oxide (ZnO:Al) thin film is usually used as a front transparent conductive oxide (TCO) contact on photovoltaic devices, and for this application is often deposited by a reactive radio-frequency (r.f.) magnetron sputtering system from a ceramic target. This work reports on the preparation and characterization of AZO thin films on Corning 1737 glass substrates grown by reactive r.f.-magnetron sputtering from a ZnO ceramic target with 2 wt% Al content. It was found that the growth parameters, such as chamber pressure, working power, and deposition temperature, have significant influences on the properties of AZO films. According to the experimental results: (1) Films were polycrystalline showing a strong preferred c-axis orientation. (2) With increasing working power, the resistivity decreased, and mobility and the carrier concentration increased. (3) Lower deposition temperature leads to a decrease in resistivity, with 2.5×10-4 Ω-cm representing the lowest resistivity reached.
Ronnie Vernooy, Senior Programme Specialist, International Development Research Centre (IDRC), Canada,Li Xiaoyun, Senior Programme Specialist, International Development Research Centre (IDRC), Canada,Xu Xiuli, Senior Programme Specialist, International Development Research Centre (IDRC), Canada,Lu Min, Senior Programme Specialist, International Development Research Centre (IDRC), Canada,Qi Gubo, Senior Programme Specialist, International Development Research Centre (IDRC), Canada
This work reports on the fabrication and characterization of Mo thin films on soda-lime glass substrate grown by reactive RF magnetron sputtering. Film thickness was measured by x-ray step surface profiler. The structural properties and surface morphology were analyzed by x-ray diffraction (XRD), atomic force microscope (AFM) and scanning electron microscopy (SEM). Electrical properties were measured by four-point probe. It was found that the growth parameters, such as argon flow rate, RF power, film thickness, have significant influences on properties of Mo films. The strain on films revealed the complicated relationship with the working pressure, which might be associated with micro structures and impurities. In order to improve the adhesion and electricity, we adopted a two-pressure deposition scheme. The optimal thickness and sheet resistance are νm and 0.12 ω The mechanisms therein will be discussed in detail. Furthermore, we also investigated the diffusion property of Na ion of double Mo films sputtered on soda-lime glass. Our experimental results could lead to better understanding for improving further CIGS-based photovoltaic devices.