To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
The association between dietary Fe intake and diabetes risk remains inconsistent. We aimed to explore the association between dietary Fe intake and type 2 diabetes mellitus (T2DM) risk in middle-aged and older adults in urban China. This study used data from the Guangzhou Nutrition and Health Study, an on-going community-based prospective cohort study. Participants were recruited from 2008 to 2013 in Guangzhou community. A total of 2696 participants aged 40–75 years without T2DM at baseline were included in data analyses, with a median of 5·6 (interquartile range 4·1–5·9) years of follow-up. T2DM was identified by self-reported diagnosis, fasting glucose ≥ 7·0 mmol/l or glycosylated Hb ≥ 6·5 %. Cox proportional hazard models were used to estimate hazard ratios (HR) and 95 % CI. We ascertained 205 incident T2DM cases during 13 476 person-years. The adjusted HR for T2DM risk in the fourth quartile of haem Fe intake was 1·92 (95 % CI 1·07, 3·46; Ptrend = 0·010), compared with the first quartile intake. These significant associations were found in haem Fe intake from total meat (HR 2·74; 95 % CI 1·22, 6·15; Ptrend = 0·011) and haem Fe intake from red meat (HR 1·86; 95 % CI 1·01, 3·44; Ptrend = 0·034), but not haem Fe intake from processed meat, poultry or fish/shellfish. The association between dietary intake of total Fe or non-haem Fe with T2DM risk had no significance. Our findings suggested that higher dietary intake of haem Fe (especially from red meat), but not total Fe or non-haem Fe, was associated with greater T2DM risk in middle-aged and older adults.
Schizotypy refers to schizophrenia-like traits below the clinical threshold in the general population. The pathological development of schizophrenia has been postulated to evolve from the initial coexistence of ‘brain disconnection’ and ‘brain connectivity compensation’ to ‘brain connectivity decompensation’.
In this study, we examined the brain connectivity changes associated with schizotypy by combining brain white matter structural connectivity, static and dynamic functional connectivity analysis of diffusion tensor imaging data and resting-state functional magnetic resonance imaging data. A total of 87 participants with a high level of schizotypal traits and 122 control participants completed the experiment. Group differences in whole-brain white matter structural connectivity probability, static mean functional connectivity strength, dynamic functional connectivity variability and stability among 264 brain sub-regions of interests were investigated.
We found that individuals with high schizotypy exhibited increased structural connectivity probability within the task control network and within the default mode network; increased variability and decreased stability of functional connectivity within the default mode network and between the auditory network and the subcortical network; and decreased static mean functional connectivity strength mainly associated with the sensorimotor network, the default mode network and the task control network.
These findings highlight the specific changes in brain connectivity associated with schizotypy and indicate that both decompensatory and compensatory changes in structural connectivity within the default mode network and the task control network in the context of whole-brain functional disconnection may be an important neurobiological correlate in individuals with high schizotypy.
A higher dietary intake or serum concentration of betaine has been associated with greater lean body mass in middle-aged and older adults. However, it remains unknown whether betaine intake is associated with age-related loss of skeletal muscle mass (SMM). We assessed the association between dietary betaine intake and relative changes in SMM after 3 years in middle-aged adults. A total of 1242 participants aged 41–60 years from the Guangzhou Nutrition and Health Study 2011–2013 and 2014–2017 with body composition measurements by dual-energy X-ray absorptiometry were included. A face-to-face questionnaire was used to collect general baseline information. After adjustment for potential confounders, multiple linear regression found that energy-adjusted dietary betaine intake was significantly and positively associated with relative changes (i.e. percentage loss or increase) in SMM of legs, limbs and appendicular skeletal mass index (ASMI) over 3 years of follow-up (β 0·322 (se 0·157), 0·309 (se 0·142) and 0·303 (se 0·145), respectively; P < 0·05). The ANCOVA models revealed that participants in the highest betaine tertile had significantly less loss in SMM of limbs and ASMI and more increase in SMM of legs over 3 years of follow-up, compared with those in the bottom betaine tertile (all Ptrend < 0·05). In conclusion, our findings suggest that elevated higher dietary betaine intake may be associated with less loss of SMM of legs, limbs and ASMI in middle-aged adults.
Hydrogen lithography has been used to template phosphine-based surface chemistry to fabricate atomic-scale devices, a process we abbreviate as atomic precision advanced manufacturing (APAM). Here, we use mid-infrared variable angle spectroscopic ellipsometry (IR-VASE) to characterize single-nanometer thickness phosphorus dopant layers (δ-layers) in silicon made using APAM compatible processes. A large Drude response is directly attributable to the δ-layer and can be used for nondestructive monitoring of the condition of the APAM layer when integrating additional processing steps. The carrier density and mobility extracted from our room temperature IR-VASE measurements are consistent with cryogenic magneto-transport measurements, showing that APAM δ-layers function at room temperature. Finally, the permittivity extracted from these measurements shows that the doping in the APAM δ-layers is so large that their low-frequency in-plane response is reminiscent of a silicide. However, there is no indication of a plasma resonance, likely due to reduced dimensionality and/or low scattering lifetime.
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.
Attention-deficit/hyperactivity disorder (ADHD) is associated with a higher risk of burn injury than in the normal population. Nevertheless, the influence of methylphenidate (MPH) on the risk of burn injury remains unclear. This retrospective cohort study analysed the effect of MPH on the risk of burn injury in children with ADHD.
Data were from Taiwan's National Health Insurance Research Database (NHIRD). The sample comprised individuals younger than 18 years with a diagnosis of ADHD (n = 90 634) in Taiwan's NHIRD between January 1996 and December 2013. We examined the cumulative effect of MPH on burn injury risk using Cox proportional hazards models. We conducted a sensitivity analysis for immortal time bias using a time-dependent Cox model and within-patient comparisons using the self-controlled case series model.
Children with ADHD taking MPH had a reduced risk of burn injury, with a cumulative duration of treatment dose-related effect, compared with those not taking MPH. Compared with children with ADHD not taking MPH, the adjusted hazard ratio for burn injury was 0.70 in children taking MPH for <90 days (95% confidence interval (CI) 0.64–0.77) and 0.43 in children taking MPH for ≥90 days (95% CI 0.40–0.47), with a 50.8% preventable fraction. The negative association of MPH was replicated in age-stratified analysis using time-dependent Cox regression and self-controlled case series models.
This study showed that MPH treatment was associated with a lower risk of burn injury in a cumulative duration of treatment dose-related effect manner.
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.
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.
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.
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.