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Developmental dyslexia is characterized by unexpectedly low reading ability in people who have adequate nonverbal intelligence, have acquired typical schooling, and have experienced sufficient sociocultural opportunities (Gabrieli, 2009; Peterson & Pennington, 2012). It is a recognized disorder in many literate societies and has been studied in a large variety of languages (Caravolas, 2005). The Chinese writing system presents sharp contrast to the alphabetic writing system in terms of how the graphic unit maps onto phonology and semantics. Thus, the investigations into the mechanisms for Chinese reading disability are important to the understanding of the universal and language-specific mechanisms of developmental dyslexia. The behavioral and neural correlates of Chinese developmental dyslexia have been studied extensively in the past twenty years or so, providing us with a rich understanding of Chinese developmental dyslexia.
Existing data on folate status and hepatocellular carcinoma (HCC) prognosis are scarce. We prospectively examined whether serum folate concentrations at diagnosis were associated with liver cancer-specific survival (LCSS) and overall survival (OS) among 982 patients with newly diagnosed, previously untreated HCC, who were enrolled in the Guangdong Liver Cancer Cohort (GLCC) study between September 2013 and February 2017. Serum folate concentrations were measured using chemiluminescent microparticle immunoassay. Cox proportional hazards models were performed to estimate hazard ratios (HR) and 95 % CI by sex-specific quartile of serum folate. Compared with patients in the third quartile of serum folate, patients in the lowest quartile had significantly inferior LCSS (HR = 1·48; 95 % CI 1·05, 2·09) and OS (HR = 1·43; 95 % CI 1·03, 1·99) after adjustment for non-clinical and clinical prognostic factors. The associations were not significantly modified by sex, age at diagnosis, alcohol drinking status and Barcelona Clinic Liver Cancer (BCLC) stage. However, there were statistically significant interactions on both multiplicative and additive scale between serum folate and C-reactive protein (CRP) levels or smoking status and the associations of lower serum folate with worse LCSS and OS were only evident among patients with CRP > 3·0 mg/l or current smokers. An inverse association with LCSS were also observed among patients with liver damage score ≥3. These results suggest that lower serum folate concentrations at diagnosis are independently associated with worse HCC survival, most prominently among patients with systemic inflammation and current smokers. A future trial of folate supplementation seems to be promising in HCC patients with lower folate status.
Hepatitis B constitutes a severe public health challenge in China. The Community-based Collaborative Innovation hepatitis B (CCI-HBV) project is a national epidemiological study of hepatitis B and has been conducting a comprehensive intervention in southern Zhejiang since 2009.
The comprehensive intervention in CCI-HBV areas includes the dynamic hepatitis B screening in local residents, the normalised treatment for hepatitis B infections and the upcoming full-aged hepatitis B vaccination. After two rounds of screening (each round taking for 4 years), the initial epidemiological baseline of hepatitis B in Qinggang was obtained, a coastal community in east China. By combining key data and system dynamics modelling, the regional hepatitis B epidemic in 20 years was predicted.
There were 1041 HBsAg positive cases out of 12 228 people in Round 1 indicating HBV prevalence of 8.5%. Of the 13 146 people tested in Round 2, 1171 people were HBsAg positive, with a prevalence of 8.9%. By comparing the two rounds of screening, the HBV incidence rate of 0.192 per 100 person-years was observed. By consulting electronic medical records, the HBV onset rate of 0.533 per 100 person-years was obtained. We generated a simulated model to replicate the real-world situation for the next two decades. To evaluate the effect of interventions on regional HBV prevalence, three comparative experiments were conducted.
In this study, the regional hepatitis B epidemic in 20 years was predicted and compared with HBV prevalence under different interventions. Owing to the existing challenges in research methodology, this study combined HBV field research and simulation to provide a system dynamics model with close-to-real key data to improve prediction accuracy. The simulation also provided a prompt guidance for the field implementation.
A conventional Differential GPS (DGPS) techniques-based velocity and acceleration method (named here as ‘DVA’) may be difficult to implement in the Antarctic as there is a sparse distribution of reference stations over Antarctica. Thus, in order to overcome the baseline limitations and to obtain highly accurate and reliable velocity and acceleration estimates for airborne gravimetry, a network-based velocity and acceleration determination approach (named here as ‘NVA’), which introduces a wide network of stations and is independent of precise clock information, is applied. Here its performance for velocity and acceleration determination is fully exploited by using Global Positioning System (GPS), GLONASS, Galileo and BeiDou observations. Additionally, a standalone receiver-based method named ‘SVA’, which requires precise clock information, is also implemented for comparison. During static tests and a flight experiment over Antarctica, it was found that the NVA method yields more robust results than the SVA and DVA methods when applied to a wide area network. Moreover, the addition of GLONASS, Galileo and BeiDou systems can increase the accuracy of velocity and acceleration estimates by 39% and 43% with NVA compared to a GPS-only solution.
We suggest a new method to evaluate stress directionality, the ratio of principal stresses, using nanoindentation by introducing a modified Berkovich indenter that is extended in one direction from the Berkovich indenter. In a nonequibiaxial stress state, the indentation load-depth curves are shifted differently as the extended axis of the indenter is placed in accordance with each principal direction. The indentation load-difference is proportional to each principal stress and the slopes are defined by the normal and parallel conversion factors whose ratio is constant at 0.58. The suggested method was verified by indentation tests using five nonequibiaxial stressed specimens. The evaluated stress directionality results show agreement with the applied reference values within ±20%. Furthermore, we calculated the conversion factor ratios for other modified Berkovich indenters extended to different degrees through finite element analysis and confirmed that the conversion factor ratio was inversely proportional to the extension of the modified Berkovich indenter.
To identify the prevalence of posttraumatic stress disorder (PTSD) and its determinants among adolescents more than 4 years after the 2008 Wenchuan earthquake.
Adolescents (1,125 total) from 2 junior high schools in areas affected by the catastrophic earthquake were followed up for 3 years. The self-rating PTSD scale based on the Manual of Mental Disorders, 4th Edition (DSM-IV) and the Chinese Classification and Diagnostic Criteria of Mental Disorders, 2nd Edition, Revised (CCMD-2-R) was collected at 53 months, and determinant data were collected repeatedly. Logistic regression was used for a determinants analysis.
The prevalence of overall PTSD was 23.4% among the sample. The risk factors for PTSD were older age (OR=1.52, 95% CI: 1.20~1.92), and death or injury of a family member in the earthquake (OR=1.61, 95% CI: 1.09~2.37). Adolescents who had moderate-to-severe common mental health problems were more likely to have PTSD symptoms, with ORs from 3.98 to 17.67 (All P<0.05). Self-esteem remained a protective factor for PTSD regardless of age, whereas positive coping was a protective factor for PTSD when adolescents were older.
PTSD symptoms among adolescent survivors of a catastrophic earthquake seemed to persist over time. Long-term interventions are needed to alleviate PTSD symptoms among adolescent survivors. (Disaster Med Public Health Preparedness. 2019;13:414-418)
In response to how they are compensated, mutual fund managers who are underperforming by mid-year are likely to increase the risk of their portfolios toward the year-end. We argue that an increase in the liquidity of the stocks that managers use to shift risk can lead to an increase in the size of their risky bets. This in turn hurts fund investors by increasing the costs of misaligned incentives associated with delegated portfolio management. We provide both theoretical and empirical results that are consistent with this argument. We use decimalization as an exogenous shock to liquidity to identify causal effects.
We are constructing a collector for capturing Interplanetary Dust Particles (IDPs) and space debris on space shuttle. The unit consists of three pieces of thin polyester film, equally spaced 7 cm apart, and an aerogel disk of 3 cm thickness. For each particle captured in the aerogel disk, we determine its direction of impact and its speed, from which we can trace its trajectory. The purpose of the experiment is to study the compositions of IDPs from different origins.
Previous studies in China showed large sex differences in childhood overweight and obesity (OW/OB) rates. However, limited research has examined the cause of these sex differences. The present study aimed to examine individual and parental/familial factors associated with sex differences in childhood OW/OB rates in China.
Variables associated with child weight status, beliefs and behaviours, and obesity-related parenting practices were selected to examine their sex differences and association with a sex difference in child OW/OB outcomes using logistic regression analysis.
Cross-sectional data analysis using the 2011 China Health and Nutrition Survey.
Children aged 6–17 years (n 1544) and their parents.
Overall child OW/OB prevalence was 16·8 %. Adolescent boys (AB; 12–17 years) were about twice as likely to be overweight/obese as adolescent girls (AG; 15·5 v. 8·4 %, P<0·05). AB more likely had energy intake exceeding recommendations, self-perceived underweight, underestimated their body weight and were satisfied with their physical activity level than AG. AG more likely practised weight-loss management through diet and self-perceived overweight than AB. Mothers more likely identified AG’s weight accurately but underestimated AB’s weight. Stronger associations with risk of childhood OW/OB were found in boys than girls in dieting to lose weight (OR=6·7 in boys v. 2·6 in girls) and combined maternal and child perception of the child’s overweight (OR=35·4 in boys v. 14·2 in girls).
Large sex differences in childhood obesity may be related to the sex disparities in weight-related beliefs and behaviours among children and their parents in China.
This study examined how financial strain, worry about having no care-giver and social engagement modify the association between widowhood and depressive symptoms among older adults in China. Using national representative data from older adults in China in 2006, we ran structural equation models and ordinary least square regressions to investigate the mediating and moderating effects of financial strain, worry about having no care-giver and social engagement on the association between widowhood and depressive symptoms. All three variables significantly mediated the association between widowhood and depressive symptoms. Compared to their married counterparts, widowed older adults showed more worry about having no care-giver, increased financial strain and lower social engagement, which were significantly associated with depressive symptoms. Higher level of worry about having no care-giver and lower social engagement significantly exacerbated the adverse effects of widowhood on depressive symptoms in the moderation analyses. Our finding of mediating effects suggests that widowhood is negatively related to psychological wellbeing via financial strain, social engagement and care resources. The results regarding moderating effects suggest that alleviating worry about having no care-giver and increasing social engagement may buffer the deleterious effect of widowhood on psychological wellbeing in later life.
In this work, the reduction mechanism of potassium chromate (K2CrO4) was investigated via in situ high-temperature X-ray diffraction coupled with Fourier transform infrared spectroscopy. During the hydrogen reduction of K2CrO4, the formation of K3CrO4, KCrO2, and KxCrO2 were detected for the first time. The study discovered that K2CrO4 was firstly reduced to K3CrO4 and an amorphous Cr(III) intermediate product at low temperature (400–500 °C). Moreover, the K3CrO4 was the only crystalline material at this stage. As the temperature increased, a stabilized amorphous CrOOH was formed. At a high temperature (550–700 °C), KCrO2 was generated. Interestingly, a portion of KCrO2 was spontaneously decomposed during the hydrogen reduction, accompanying by the formation of K0.7CrO2. Finally, the results clearly illustrated the reduction mechanism of K2CrO4: K2CrO4 → K3CrO4 → amorphous intermediate → KCrO2.
A study in rodent models showed that phytosterols protected against colon carcinogenesis, probably by inhibiting dysregulated cell cycle progression and inducing cellular apoptosis. However, epidemiological studies on the relationship between phytosterols and colorectal cancer risk are quite limited. The aim of this study was to investigate dietary phytosterol intake in relation to colorectal cancer risk in the Chinese population. A case–control study was conducted from July 2010 to June 2016, recruiting 1802 eligible colorectal cancer cases plus 1813 age (5-year interval) and sex frequency-matched controls. Dietary information was collected by using a validated FFQ. The OR and 95 % CI of colorectal cancer risk were assessed by multivariable logistic regression models. A higher total intake of phytosterols was found to be associated with a 50 % reduction in colorectal cancer risk. After adjusting for various confounders, the OR of the highest quartile intake compared with the lowest quartile intake was 0·50 (95 % CI 0·41, 0·61, Ptrend<0·01) for total phytosterols. An inverse association was also found between the consumption of β-sitosterol, campesterol, campestanol and colorectal cancer risk. However, stigmasterol intake was related to an increased risk of colorectal cancer. No statistically significant association was found between β-sitostanol and colorectal cancer risk. Stratified analysis by sex showed that the positive association of stigmasterol intake with colorectal cancer risk was found only in women. These data indicated that the consumption of total phytosterols, β-sitosterol, campesterol and campestanol is inversely associated with colorectal cancer risk in a Chinese population.
Background: Good primary health care can enhance national health status at relatively low cost. The barefoot doctor model in China was once considered to have been a successful health care policy. It was a model which was followed by other low-developed or developing countries. In recent decades, the Chinese government promulgated a number of new policies and health reforms to improve its health care system. Aim: This paper aimed to highlight the great significance of primary health care and appeal to the policymakers to change the priority to primary health care in order to be able to guarantee universal health care for the whole nation at least at primary care level. Method: This study discussed Chinese primary health care by reviewing its history and development. Finding: Chinese government’s efforts do not seem to be leading to a completely successful outcome for all the people of China as a result of the substantial imbalance of investments between tertiary level hospitals and grass-root level health care institutions. The government appears to have neglected the importance of primary health care in the implementation of health systems and resources.
To evaluate the effects of different anthropogenic activities on zooplankton and the pelagic ecosystem, we conducted seasonal cruises in 2010 to assess spatial heterogeneity among the mesozooplankton communities of Xiangshan Bay, a subtropical semi-enclosed bay in China. The evaluation included five different areas: a kelp farm, an oyster farm, a fish farm, the thermal discharge area of a power plant, and an artificial reef, and we aimed to identify whether anthropogenic activities dominated spatial variation in the mesozooplankton communities. The results demonstrated clear spatial heterogeneity among the mesozooplankton communities of the studied areas, dominantly driven by natural hydrographic properties, except in the area near the thermal discharge outlet of the power station. In the outlet area, thermal shock caused by the discharge influenced the mesozooplankton community by decreasing abundance and biomass throughout the four seasons, even causing a shift in the dominant species near the outlet during summer from Acartia pacifica to eurythermal and warm water taxa. Unique features of the mesozooplankton community in the oyster farm may be due to the combined effects of oyster culture and the natural environment in the branch harbour. However, kelp and fish culture, and the construction of an artificial reef did not exert any obvious influence on the mesozooplankton communities up to 2010, probably because of the small scale of the aquaculture and a time lag in the rehabilitation effects of the artificial reef. Thus, our results suggested that the dominant factors influencing spatial variations of mesozooplankton communities in Xiangshan Bay were still the natural hydrographic properties, but the thermal discharge was an anthropogenic activity that changed the pelagic ecosystem, and should be supervised.
The hydrogen concentration and composition of garnets in the ultrahigh pressure eclogites at Shuanghe, eastern Dabieshan, were investigated using Fourier transform infrared spectroscopy and electron microprobe analysis. The OH absorption bands can be divided into four groups: (1) 3635–3655 cm–1; (2) 3600–3630 cm–1; (3) 3540–3580 cm–1; and (4) 3400–3450 cm–1 and the water content ranges from 45 to 2529 ppm. Based on the behaviour of the OH absorption band and the relationship between water content and the composition of garnets, the samples can be divided into two classes: samples with >400 ppm H2O and samples with ≤400 ppm H2O. The water content of the former shows an obvious positive correlation with Ca atoms and a negative correlation with the Si, Mg and Fe2+ atoms per 12 anions, whereas the water content of the latter shows no obvious linear correlation with cations. It is concluded that the major mechanism of hydroxyl incorporation in garnets with >400 ppm H2O is by the coupled substitution 4H +Z□ → □+ZSi in the tetrahedral site, and that several mechanisms are responsible for OH incorporation in garnets with ≤400 ppm H2O.
Flavonoids may play an important role in the protective effects of vegetables, fruits and tea against colorectal cancer. However, associations between flavonoids and colorectal cancer risk are inconsistent, and a few studies have evaluated the effect of flavonoids from different dietary sources separately. This study aimed to evaluate associations of flavonoids intake from different dietary sources with colorectal cancer risk in a Chinese population. From July 2010 to December 2015, 1632 eligible colorectal cancer cases and 1632 frequency-matched controls (age and sex) completed in-person interviews. A validated FFQ was used to estimate dietary flavonoids intake. Multivariate logistical regression models were used to calculate the OR and 95 % CI of colorectal cancer risk after adjusting for various confounders. No significant association was found between total flavonoids and colorectal cancer risk, with an adjusted OR of 1·06 (95 % CI 0·85, 1·32) comparing the highest with the lowest quartile. Anthocyanidins, flavanones and flavones intakes from total diet were found to be inversely associated with colorectal cancer risk. Compared with the lowest quartile, the adjusted OR for the highest quartile were 0·80 (95 % CI 0·64, 1·00) for anthocyanidins, 0·28 (95 % CI 0·22, 0·36) for flavanones and 0·54 (95 % CI 0·43, 0·67) for flavones. All subclasses of flavonoids from vegetables and fruits were inversely associated with colorectal cancer. However, no significant association was found between tea flavonoids and colorectal cancer risk. These data indicate that specific flavonoids, specifically flavonoids from vegetables and fruits, may be linked with the reduced risk of colorectal cancer.
Part of the energy of low solar corona may be released and converted to plasma energy that may be the dominant source of solar flares. Recently, many physical mechanisms have been proposed to accelerate ions and electrons. In the magnetic mirror device of fusion research, ion cyclotron instability and the energetic ion losses have been discovered and the plasma becomes electron rich.
The study of flapping-wing aerodynamics faces a large control space with different wing kinematics and deformation. The adjoint-based approach, by solving an inverse problem to obtain simultaneously the sensitivity with respect to all control parameters, has a computational cost independent of the number of control parameters and becomes an efficient tool for the study of problems with a large control space. However, the adjoint equation is typically formulated in a fixed fluid domain. In a continuous formulation, a moving boundary or morphing domain results in inconsistency in the definition of an arbitrary perturbation at the boundary, which leads to ambiguousness and difficulty in the adjoint formulation if control parameters are related to boundary changes (e.g. the control of wing kinematics and dynamic deformation). The unsteady mapping function, as a traditional way to deal with moving boundaries, can in principle be a remedy for this situation. However, the derivation is often too complex to be feasible, even for simple problems. Part of the complexity comes from the unnecessary mapping of the interior mesh, while only mapping of the boundary is needed here. Non-cylindrical calculus, on the other hand, provides a boundary mapping and considers the rest of domain as an arbitrary extension from the boundary. Using non-cylindrical calculus to handle moving boundaries makes the derivation of the adjoint formulation much easier and also provides a simpler final formulation. The new adjoint-based optimization approach is validated for accuracy and efficiency by a well-defined case where a rigid plate plunges normally to an incoming flow. Then, the approach is applied for the optimization of drag reduction and propulsive efficiency of first a rigid plate and then a flexible plate which both flap with plunging and pitching motions against an incoming flow. For the rigid plate, the phase delay between pitching and plunging is the control and considered as both a constant (i.e. a single parameter) and a time-varying function (i.e. multiple parameters). The comparison between its arbitrary initial status and the two optimal solutions (with a single parameter or multiple parameters) reveals the mechanism and control strategy to reach the maximum thrust performance or propulsive efficiency. Essentially, the control is trying to benefit from both lift-induced thrust and viscous drag (by reducing it), and the viscous drag plays a dominant role in the optimization of efficiency. For the flexible plate, the control includes the amplitude and phase delay of the pitching motion and the leading eigenmodes to characterize the deformation. It is clear that flexibility brings about substantial improvement in both thrust performance and propulsive efficiency. Finally, the adjoint-based approach is extended to a three-dimensional study of a rectangular plate in hovering motion for lift performance. Both rigid and flexible cases are considered. The adjoint-based algorithm finds an optimal hovering motion with advanced rotation which has a large leading-edge vortex and strong downwash for lift benefit, and the introduction of flexibility enhances the wake capturing mechanism and generates a stronger downwash to push the lift coefficient higher.
Generally, the obvious work hardening, dynamic recrystallization (DRX), and dynamic recovery behaviors can be found during hot deformation of Ni-based superalloys. In the present study, the classical dislocation density theory is improved by introducing a new dislocation annihilation item to represent the influences of DRX on dislocation density evolution for a Ni-based superalloy. Based on the improved dislocation density theory, the peak strain corresponding to peak stress and the critical strain for initiating DRX can be determined, and the improved DRX kinetics equations and grain size evolution models are developed. The physical framework and algorithmic idea of the improved dislocation density theory are clarified. Moreover, the deformed microstructures are characterized and quantitatively correlated to validate the improved dislocation density theory. It is found that the improved dislocation density-based models can precisely characterize hot deformation and DRX behaviors for the studied superalloy under the tested conditions.
During the 20th century a range of museums in the United States were engaged in acquiring Chinese art objects, developing major collections of painting and calligraphy, ancient bronze, Buddhist sculpture, ceramics and other decorative arts. Research materials on Chinese art have been collected by art libraries in major museums and the East Asian libraries of the main research universities. The author surveys significant Chinese art collections in museums and research libraries in the United States today.