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Chinese morphological awareness is conceptualized as a multidimensional construct but there is a lack of understanding of how its dimensions are related. Latent change score modeling was used to examine the bivariate relationships of two facets of oral morphological awareness, namely morpheme and structure awareness in Chinese children in grades one through three. Two hundred and three children in China completed morpheme (homonym awareness) and structure awareness (lexical compounding) tasks across the three grades (M = 6.66, SD = .30 at the first time point). Results indicated that growth in structure awareness was predicted in part by previous levels of morpheme awareness, suggesting that morpheme awareness leads the growth of structure awareness. Educational implications are discussed.
Potential secondary influences on titanium distribution should be evaluated when using ash beds as volcanic source indicators and for correlation purposes. In this study, well-correlated altered ash beds in Permian–Triassic boundary (PTB) successions of various facies in South China were investigated to better understand their use in source discrimination and stratigraphic correlation. The ash beds deposited in lacustrine and paludal facies contain significantly more Ti relative to deposits in marine facies. Neoformed anatase grains nanometres to micrometres in size are associated closely with clay minerals, whereas detrital anatase was observed in the remnants of altered ash beds of terrestrial facies. Extraction of the clay fraction of altered ash beds may exclude significantly detrital accessory minerals such as anatase and rutile added during sediment reworking, and the concentrations of immobile elements in the clay fraction may therefore be used to interpret more effectively their source igneous rocks.
This study aimed to determine whether increased carotenoids intake was associated with reduced risk of gestational diabetes mellitus (GDM). We performed a cross-sectional analysis using data from Tongji Maternal and Child Health Cohort study. The dietary carotenoids intake of 1978 pregnant women was assessed using a researcher-administered FFQ before undertaking an oral glucose tolerance test at 24–28 weeks. Multivariate logistic and linear regression analyses were used to obtain the effect estimates. Participants in the highest quartile of lycopene intake showed a lower risk of GDM (OR 0·50; 95 % CI 0·29, 0·86; Pfor trend = 0·007) compared with those in the lowest quartile; each 1 mg increase in lycopene consumption was associated with a 5 % (95 % CI 0·91, 0·99; Pfor trend = 0·020) decrease in GDM risk. No significant association was found between α-carotene, β-carotene, β-cryptoxanthin, lutein/zeaxanthin intake and GDM risk. Multiple linear regression analysis suggested an inverse association between lycopene intake and fasting blood glucose (FBG) (Pfor trend < 0·001); each 1 mg increase in lycopene intake was associated with 0·005 (95 % CI 0·002, 0·007; Pfor trend < 0·001) mmol/l decrease in FBG. Interaction analysis indicated consistent effect on each age or pre-BMI subgroup; however, a stronger protective effect of lycopene intake against GDM was observed among primigravid women (OR 0·20; 95 % CI 0·07, 0·55 in the highest v. the lowest quartile of intake; Pfor interaction = 0·036). In conclusion, dietary lycopene intake was mainly assumed via reducing FBG to decrease GDM risk, and the protection was relatively increased among primigravid women.
Inflammation plays a pivotal role in the pathogenesis of atherosclerosis and of cerebrovascular complications. Transforming growth factor-β (TGF-β) is a pleiotropic cytokine with a central role in inflammation. To investigate whether polymorphisms of the TGF-β1 gene can modify the risk of ischemic stroke (IS) in Chinese population, we conduct this hospital-based, case-control study.
Transforming growth factor-β1 genotype was determined in 450 Chinese patients (306 male and 144 female) with IS and 450 control subjects (326 male and 124 female).
Subjects carrying 869TT were susceptible to IS (odds ratio [OR] =1.58; P=0.003). Further analysis of IS data partitioned by gender revealed the female-specific association with 869T/C (OR=2.64; P=0.001).
Findings suggest that the TT genotype of 869T/C might be a risk factor of IS in Chinese, especially in females.
Serum vitamin D (25-hydroxyvitamin D (25OHD)) may influence serum parathyroid hormone (PTH) levels and bone mineral density (BMD). In the present study, we assessed serum 25OHD concentration and its association with PTH and BMD in urban males from Guiyang (N26.57°), the capital city of Guizhou province, Southwest China. We recruited 634 males aged >20 years from the Guiyang Health Measures Survey, and stratified them into three groups according to age: young (20–39 years), middle aged (40–59 years) and older (60–79 years). We measured serum concentrations of 25OHD, PTH levels and BMD of the lumbar spine (L1–L4), femoral neck and total hip. In addition, we also explored the relationship between 25OHD and lifestyle, socio-economic characteristics and medical history by applying covariance analysis and locally weighted regression plots. The results showed that serum 25OHD was <50 nmol/l in 59·3 % of the subjects and >75 nmol/l in 12·6 % of the subjects. Higher level of serum PTH was detected in relation to lower concentrations of serum 25OHD up to 50 nmol/l. A negative correlation between serum 25OHD and PTH concentrations was observed (r −0·207, P=0·003). Mean concentration of serum PTH increased gradually and plateaued while concentrations of serum 25OHD decreased to 50 nmol/l. Gradual increase in serum PTH was observed as 25OHD concentration was <25 nmol/l (P=0·004). BMD values at all sites were greater in the higher serum 25OHD concentration group. This study shows that low concentrations of serum 25OHD were common in males, and bone health was likely to be improved when serum 25OHD values were between 30 and 50 nmol/l.
The scaled boundary finite element method (SBFEM) is a semi-analytical computational method initially developed in the 1990s. It has been widely applied in the fields of solid mechanics, oceanic, geotechnical, hydraulic, electromagnetic and acoustic engineering problems. Most of the published work on SBFEM has focused on its theoretical development and practical applications, but, so far, no explicit discussion on the numerical stability and accuracy of its solution has been systematically documented. However, for a reliable engineering application, the inherent numerical problems associated with SBFEM solution procedures require thorough analysis in terms of its causes and the corresponding remedies. This study investigates the numerical performance of SBFEM with respect to matrix manipulation techniques and their properties. Some illustrative examples are given to identify reasons for possible numerical difficulties, and corresponding solution schemes are proposed to overcome these problems.
Transforming growth factor beta1 (TGFβ1) is a multifunctional cytokine involved in inflammation and pathogenesis of atherosclerosis. The aim of the present study was to investigate the relationship between human TGFβ1 gene +869T>C (rs1800470), -509C>T (rs1800469) single nucleotide polymorphisms (SNPs) and haplotypes and cerebral infarction (CI) in a Chinese population.
The genetic association study was performed in 450 Chinese patients (306 male and 144 female) with CI and 450 control subjects (326 male and 124 female). TGFβ1 gene +869T>C and -509C>T polymorphisms were identified with amplification refractory mutation system polymerase chain reaction and DNA sequencing method.
The individual SNPs analysis showed the +869T and -509C in an additive model (+869T vs +869C; -509 C vs T), +869TT genotype in a recessive model (TT vs TC+CC) and 509CC genotype in a dominant model (CC+ CT vs TT) were identified to be related to CI (P<0.05). +869T>C and -509C>T SNPs were in strong linkage disequilibrium (d'=0.87, R2=0.75). Haplotype analysis showed that +869C/-509T haplotype was associated with a significant decreased risk of CI (OR= 0.86, 95%CI, 0.70-0.92; P=0.007). Furthermore,+869T/-509C haplotype was associated with a significant increased risk of CI (OR=1.31, 95%CI, 1.10-2.03; P=0.019).
The results of this study indicate that polymorphisms and the haplotypes in the TGFβ1 gene might be genetic markers for CI in the Chinese population.
To assess the relationship between carotid flow velocity and cognitive impairment in patients with mild-moderate (<50%) carotid artery disease.
We studied 407 participants with available carotid ultrasound and cognitive measures. We related peak systolic velocity (PSV) and end diastolic velocity (EDV) of internal carotid artery (ICA) and common carotid artery (CCA) and intimal medial thickness (IMT) to Mini Mental State Examination (MMSE), Clock Draw Test (CDT), Activities of Daily Living Scale (ADL)and Montreal Cognitive Assessment (MoCA).
EDV of CCA was significantly different in higher and lower MoCA (MMSE) groups. Multiple regression analysis demonstrated that lower EDV was significantly associated with lower MoCA (+0.459 per standard deviation (SD), p<0. 01 for the left; +0.539 per SD, p<0. 01 for the right) and CDT (odds ratio (OR) 0.093, p< 0.05 for the left; OR) 0.120, p<0. 01 for the right) scores. PSV of left CCA (-0.205 per SD, p<0.05) and IMT (+42.536 per SD, p< 0.001) were associated with ADL. PSV of right CCA was associated with MMSE (+0.081 per SD, p<0.001). No significant relationship between ICA flow velocity and cognitive performance was observed.
Our preliminary data show that common carotid artery flow velocity was associated with cognitive performance.
The angiotensin-1 converting enzyme (ACE) gene is known to have two polymorphic alleles insertion/deletion(I/D). People with the DD genotype have been shown to be at greater risk of cerebral infarction, but only in some studies. Identification of cerebral infarction susceptibility genes and quantification of associated risks have been hampered by conflicting results from underpowered case-control studies. This meta-analysis was made to look specifically into the genetics of cerebral infarction among Han Chinese population.
Genetic associations studies published from January 1, 1990 to December 30, 2007 were collected from databases of MEDLINE, EMBASE, CBM and CNKI. Data were extracted using standardised forms and pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated.
Twenty-nine original case-control studies of Han Chinese population, comprising 3654 patients with cerebral infarction and 3058 controls were included in the meta-analysis. Using the random effects model, the pooled ORs of ACE DD genotype VS ID+ II was 1.91 (95% CI 1.56 to 2.34, P<0.00001).
These data suggest that the ACE DD genotype may be a risk factor for cerebral infarction in Han Chinese population. A large scale case-control study is needed to clarify the functional effect of the polymorphism of the ACE I/D gene in the pathogenesis of cerebral infarction in Han Chinese population.
To clarify the role of inflammation in the pathogenesis of cerebral small vessel disease (SVD), we investigated whether the gene encoding transforming growth factor-beta 1(TGF-beta 1) is a risk factor for cerebral SVD as a whole, and for two different SVD subtypes.
TGF-beta 1 codon10 (T+29C) genotype was determined in 441 Chinese patients (313 male and 128 female) with cerebral SVD and 450 control subjects (326 male and 124 female). Cerebral SVD patients were retrospectively classified into two groups based on neuroimaging findings: lacunar infarction group with 112 patients and ischaemic leukoaraiosis group with 329 patients.
Subjects carrying TT homozygote were susceptible to cerebral SVD [adjusted odds ratio (OR) =1.44, 95% confidence interval (CI), 1.05-1.98; P=0.026]. Further analysis of SVD subtypes revealed a moderate association with the ischaemic leukoaraiosis group [OR= 1.60, 95% CI, 1.14-2.25; P=0.007].
Codon 10 of TGF-beta 1 might be a risk factor for SVD, specifically in ischaemic leukoaraiosis phenotype.
Despite substantial research, uncertainty remains about the clinical and etiological heterogeneity of major depression (MD). Can meaningful and valid subtypes be identified and would they be stable cross-culturally?
Symptoms at their lifetime worst depressive episode were assessed at structured psychiatric interview in 6008 women of Han Chinese descent, age ⩾30 years, with recurrent DSM-IV MD. Latent class analysis (LCA) was performed in Mplus.
Using the nine DSM-IV MD symptomatic A criteria, the 14 disaggregated DSM-IV criteria and all independently assessed depressive symptoms (n = 27), the best LCA model identified respectively three, four and six classes. A severe and non-suicidal class was seen in all solutions, as was a mild/moderate subtype. An atypical class emerged once bidirectional neurovegetative symptoms were included. The non-suicidal class demonstrated low levels of worthlessness/guilt and hopelessness. Patterns of co-morbidity, family history, personality, environmental precipitants, recurrence and body mass index (BMI) differed meaningfully across subtypes, with the atypical class standing out as particularly distinct.
MD is a clinically complex syndrome with several detectable subtypes with distinct clinical and demographic correlates. Three subtypes were most consistently identified in our analyses: severe, atypical and non-suicidal. Severe and atypical MD have been identified in multiple prior studies in samples of European ethnicity. Our non-suicidal subtype, with low levels of guilt and hopelessness, may represent a pathoplastic variant reflecting Chinese cultural influences.
The symptoms of major depression (MD) are clinically diverse. Do they form coherent factors that might clarify the underlying nature of this important psychiatric syndrome?
Symptoms at lifetime worst depressive episode were assessed at structured psychiatric interview in 6008 women of Han Chinese descent, age ⩾30 years with recurrent DSM-IV MD. Exploratory factor analysis (EFA) and confirmatoryfactor analysis (CFA) were performed in Mplus in random split-half samples.
The preliminary EFA results were consistently supported by the findings from CFA. Analyses of the nine DSM-IV MD symptomatic A criteria revealed two factors loading on: (i) general depressive symptoms; and (ii) guilt/suicidal ideation. Examining 14 disaggregated DSM-IV criteria revealed three factors reflecting: (i) weight/appetite disturbance; (ii) general depressive symptoms; and (iii) sleep disturbance. Using all symptoms (n = 27), we identified five factors that reflected: (i) weight/appetite symptoms; (ii) general retarded depressive symptoms; (iii) atypical vegetative symptoms; (iv) suicidality/hopelessness; and (v) symptoms of agitation and anxiety.
MD is a clinically complex syndrome with several underlying correlated symptom dimensions. In addition to a general depressive symptom factor, a complete picture must include factors reflecting typical/atypical vegetative symptoms, cognitive symptoms (hopelessness/suicidal ideation), and an agitated symptom factor characterized by anxiety, guilt, helplessness and irritability. Prior cross-cultural studies, factor analyses of MD in Western populations and empirical findings in this sample showing risk factor profiles similar to those seen in Western populations suggest that our results are likely to be broadly representative of the human depressive syndrome.
Bionic engineering has been a focus in the field of robotic researches. Inverse dynamic analysis is significant for the determination of dynamic parameters of bionic robots. The present paper uses a newly developed robot modular named Sambot to construct a caterpillar robotic mechanism, and designs a gait of trapezoidal wave locomotion for it. Two open-link models are put forth to simulate the dynamic behavior of such a locomotion. The inverse dynamic differential equations are derived by Kane's method and are then solved numerically by the Runge–Kutta method of the fourth order. Based on the numerical solutions of these differential equations, the applied joint torques required to produce the harmonic trapezoidal wave locomotion are determined finally, providing us important information on the gait control of the caterpillar robotic mechanism. Finally, the theoretical values of the joint torques are applied onto the present caterpillar mechanism to perform a locomotion experiment, which verifies the effectiveness of the present dynamics analysis.
Early studies have shown that some mouse cumulus–oocyte complexes (COCs) stored at room temperature for 24 h still retained full developmental potential. In this study, we stored denuded mouse oocytes (DOs) at room temperature (25 °C) for 24 h and activated these oocytes with 10 mM SrCl2 or fertilized the oocytes by IVF. We found that nearly half of the DOs stored at room temperature for 1 day can be fertilized normally by IVF and that two foster mothers gave birth to seven pups. Embryos from stored oocytes were cultured in CZB medium with or without 1 μg/ml 17β-estradiol (E2). The numbers of embryo that developed to morula/blastocyst stage after parthenogenetic activation and IVF were significantly increased when E2 was added to the culture (p < 0.05). These results suggest that E2 might improve mouse embryo development in vitro. The birth of seven agouti pups and their healthy growth indicated that the storage of DOs at room temperature for 1 day may be a practical procedure for mammalian reproduction.
A new species of marine yeast Kluyveromyces penaeid (Saccharomycetoideae) was isolated from the heart tissue of a subadult shrimp Penaeus chinensis during tissue culture. The yeast grew well in seawater supplemented with 2% shrimp extract, but did not grow in chemically defined media. The vegetative cells reproduced by multilateral budding and formed rudimentary pseudohyphae occasionally. Asci were spheroidal and evanescent containing 2–13 smooth or oval ascospores. The best temperature for the yeast to grow was 20–25°C and 37°C was lethal. The yeast grew well in half to full strength seawater supplemented with shrimp extract, but did not grow in 25% strength seawater. The carbohydrate fermentation test was positive, the diazonium blue B and urea hydrolysis tests were negative.
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