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Hispanics/Latinos in the United States are less aware of their cholesterol levels and have a higher burden of associated adverse cardiovascular and cerebrovascular outcomes than non-Latino whites. Investigations of the associations between cholesterol levels and cognition in this population have often occurred within the context of metabolic syndrome and are limited to select lipids despite the fact that triglycerides (TGs) may be more relevant to the health of Hispanics/Latinos.
Baseline data from the Hispanic Community Health Study/Study of Latinos, collected from 2008 to 2011, was used to investigate the associations of lipid levels (i.e., TG, total cholesterol, TC; low-density and high-density lipoprotein cholesterol, LDL-C and HDL-C) with cognition (i.e., learning, memory, verbal fluency, and digit symbol substitution, DSS), adjusting for relevant confounders.
In 7413 participants ages 45 to 74 years from Central American, Cuban, Dominican, Mexican, Puerto Rican, and South American backgrounds, separate, fully adjusted linear regression models revealed that TG levels were inversely associated with DSS performance; however, this relationship was no longer significant once additional cardiovascular disease risk factors were added to the model (p = .06). TC and LDL-C levels (separately) were positively associated with learning and verbal fluency regardless of adjustments (p-values < .05). Separate analyses investigating the effect modification by background and sex revealed a particularly robust association between TC levels and DSS performance for Puerto Ricans and Central Americans (albeit in opposite directions) and an inverse relationship between TG levels and DSS performance for women (p-values < .02).
It is important to consider individual lipid levels and demographic characteristics when investigating associations between cholesterol levels and cognition in Hispanics/Latinos.
Crystal structure and electronic structure of YMnO3 were investigated by X-ray diffraction and transmission electron microscopy related techniques. According to the density of states (DOS), the individual interband transitions to energy loss peaks in the low energy loss spectrum were assigned. The hybridization of O 2p with Mn 3d and Y 4d analyzed by the partial DOS was critical to the ferroelectric nature of YMnO3. From the simulation of the energy loss near-edge structure, the fine structure of O K-edge was in good agreement with the experimental spectrum. The valence state of Mn (+3) in YMnO3 was determined by a comparison between experiment and calculations.
Starch digestion in the small intestines of the dairy cow is low, to a large extent, due to a shortage of syntheses of α-amylase. One strategy to improve the situation is to enhance the synthesis of α-amylase. The mammalian target of rapamycin (mTOR) signalling pathway, which acts as a central regulator of protein synthesis, can be activated by leucine. Our objectives were to investigate the effects of leucine on the mTOR signalling pathway and to define the associations between these signalling activities and the synthesis of pancreatic enzymes using an in vitro model of cultured Holstein dairy calf pancreatic tissue. The pancreatic tissue was incubated in culture medium containing l-leucine for 3 h, and samples were collected hourly, with the control being included but not containing l-leucine. The leucine supplementation increased α-amylase and trypsin activities and the messenger RNA expression of their coding genes (P <0.05), and it enhanced the mTOR synthesis and the phosphorylation of mTOR, ribosomal protein S6 kinase 1 and eukaryotic initiation factor 4E-binding protein 1 (P <0.05). In addition, rapamycin inhibited the mTOR signal pathway factors during leucine treatment. In sum, the leucine regulates α-amylase and trypsin synthesis in dairy calves through the regulation of the mTOR signal pathways.
Hepatitis E is an important zoonosis that is prevalent in China. Hepatitis E virus (HEV) is a pathogen that affects humans and animals and endangers public health in China. In this study, the detection of HEV epidemics in swine in Sichuan Province, China, was carried out by nested real-time PCR. A total of 174 stool samples and 160 bile samples from swine in Sichuan Province were examined. In addition, software was used to analyse the biological evolution of HEV. The results showed that within 2 years of swine HEV (SHEV) infection in China, SHEV was first detected in Sichuan Province. HEV was endemic in Sichuan; the positive rate for pig farms was 11.1%, and the total positive sample rate was 10.5%. The age of swine with the highest positive rate (17.9%) was 5–9 weeks. The examined swine species in order of highest to lowest HEV infection rates were Chenghua pig, Large White, Duroc, Pietrain, Landrace and Hampshire. Nucleotide and amino acid sequence analysis showed that the HEV epidemic in swine in Sichuan Province was related to genotype IV, which had the highest homology to HEV in Beijing. Sichuan strains have greater variation than Chinese representative strains, which may indicate the presence of new HEV strains.
Dietary intake of PUFA has been associated with colorectal neoplasm risk; however, results from observational studies have been inconsistent. Most prior studies have utilised self-reported dietary measures to assess fatty acid exposure which might be more susceptible to measurement error and biases compared with biomarkers. The purpose of this study was to determine whether erythrocyte phospholipid membrane PUFA percentages are associated with colorectal adenoma risk. We included data from 904 adenoma cases and 835 polyp-free controls who participated in the Tennessee Colorectal Polyp Study, a large colonoscopy-based case–control study. Erythrocyte membrane PUFA percentages were measured using GC. Conditional logistic regression was used to calculate adjusted OR for risk of colorectal adenomas with erythrocyte membrane PUFA. Higher erythrocyte membrane percentages of arachidonic acid was associated with an increased risk of colorectal adenomas (adjusted OR 1·66; 95 % CI 1·05, 2·62, Ptrend=0·02) comparing the highest tertile to the lowest tertile. The effect size for arachidonic acid was more pronounced when restricting the analysis to advanced adenomas only. Higher erythrocyte membrane EPA percentages were associated with a trend towards a reduced risk of advanced colorectal adenomas (Ptrend=0·05). Erythrocyte membrane arachidonic acid percentages are associated with an increased risk of colorectal adenomas.
As an industrialized city, Hong Kong annually consumes a large amount of fossil fuel. In addition, the Daya Bay Nuclear Power Plant in Shenzhen, Guangdong Province, has just begun operation 20 km from Hong Kong. These factors suggest that it may be appropriate and significant to examine the variation of atmospheric 14C levels in Hong Kong. We have collected and tested a variety of samples from different parts of Hong Kong: terrestrial annual grasses, marine plants and atmospheric CO2. We measured their 14C activity and compared it with that of cassia oil samples from Guangxi Province, China. The values obtained indicate that environmental 14C levels in the Hong Kong region agree with those found in Guangxi, both of which are significantly higher than the levels predicted by Povinec, Chudý and Šivo (1986).
The inverse problem of the Mei symmetry for nonholonomic systems with variable mass is studied. Firstly, the authors discuss the Mei symmetry of the holonomic system opposite to a nonholonomic system. Secondly, weak and strong Mei symmetries of a nonholonomic system are concluded through restriction equations and additional restriction equations. Thirdly, the relevant conserved quantity is deduced by means of the structure equation for the gauge function. Fourthly, the inverse problem of the Mei symmetry is obtained by the Noether symmetry. Finally, the paper offers an example to illustrate the application of the research result.
New-type oilseed rape (Brassica napus, ArArCcCc) with introgressed exotic subgenomic components from Brassica rapa (ArAr) and Brassica carinata (BcBcCcCc) showed strong heterosis in both vegetative and reproductive growth. The aim of the current study was to analyse the tolerance of the new-type B. napus with different exotic subgenomic contents to low nitrogen (N) stress. Under hydroponic culture and pot experiments, root system parameters, photosynthetic parameters, relative chlorophyll concentration (SPAD values), biomass, seed yield, seed yield components, N concentration and expressions of genes involved in N transport and assimilation were determined with two new-type B. napus genotypes (N-efficient genotype D4-15 and N-inefficient genotype D1-1) under high-N and low-N levels. Furthermore, N accumulation, N transfer efficiency and N use efficiency (NUE) were analysed in the two genotypes. The hydroponic and potted growth tests showed consistent characteristics in N uptake and utilization efficiency at the seedling stage, and N-efficient genotype (D4-15) showed better growth phenotypes across cultured conditions and N levels. Under the low-N condition, D4-15 produced a larger root system and accumulated more N, and had higher N transfer efficiency and NUE than D1-1. Moreover, D4-15 had significantly higher photosynthetic parameters, photosynthetic NUE and expression levels of the N transporter genes, BnNRT1·1, BnNRT2·5, BnNRT2·7 and BnAMT1·1, in roots or leaves, as well as higher seed yield than that of D1-1 under low-N supply. These results indicated that the N-efficient new-type B. napus D4-15 possessed excellent adaptability to low-N stress, which may be attributed to the highly introgressed exotic subgenomic components from B. rapa and B. carinata, suggesting the possibility of identifying high-nutrient-efficiency germplasm from inter-specific hybrids.
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.
The head and neck region is the second most frequent anatomical site of extranodal lymphomas. These tumours affect many individuals worldwide, justifying epidemiological studies in different countries. This study evaluated the characteristics, treatments and prognostic factors for non-Hodgkin's lymphoma of the head and neck in Chinese patients.
The clinical manifestations, clinicopathological characteristics, multidisciplinary treatment and prognostic factors for 102 patients with extranodal non-Hodgkin's lymphoma of the head and neck were analysed retrospectively.
The tonsil was the most commonly involved primary site, followed by the nasal cavity. The most common histological subtype was diffuse large B-cell lymphoma, followed by natural killer T-cell lymphoma. Patients receiving a combination of rituximab and chemotherapy did better than those receiving chemotherapy alone. Prognosis was significantly associated with both International Prognostic Index and histological subtype; the former was especially strongly associated with poor survival.
In this group of Chinese patients, diffuse large B-cell lymphoma was the most common pathological subtype, but the incidence of T-cell lymphomas was higher than that reported in the USA. Combined rituximab and chemotherapy led to better outcomes than chemotherapy alone. Prognosis depended on both International Prognostic Index and histological subtype.
The temperature dependence of cross-plane lattice thermal conductivity for thin film IV-VI semiconductors grown by molecular beam epitaxy was measured. Samples consisting of PbSe/PbSrSe multiple quantum wells (MQWs) on PbSe/PbSnSe superlattices (SLs) were grown with variations in SL layer thickness and the number of SL pairs. Localized lattice temperatures within the MQW layers were extracted from analysis of continuous wave photoluminescence (PL) emission spectra at heat sink temperatures between 100 K and 250 K. These data, finite element analysis, and electrical characterization were used to determine cross-plane lattice thermal conductivity of two different SL materials. A SL material with three different PbSe/PbSnSe thicknesses (1.2/1.2, 1.8/1.8, and 2.4/2.4 nm) exhibited a fairly constant lattice thermal conductivity from 1.2 to 1.3 W/mK as the sample was cooled from 250 K to 100 K. Another SL material with five different PbSe/PbSnSe thicknesses (0.5/0.5, 1.0/1.0, 1.6/1.6, 2.1/2.1, and 2.6/2.6 nm) exhibited very low lattice thermal conductivities from 0.46 to 0.47 W/mK 250 K to 100 K. These results are consistent with reflection of low energy heat transporting acoustic phonons within the SL material.
Previous studies support Beck's cognitive model of vulnerability to depression. However, the relationship between his cognitive triad and other clinical features and risk factors among those with major depression (MD) has rarely been systematically studied.
The three key cognitive symptoms of worthlessness, hopelessness and helplessness were assessed during their lifetime worst episode in 1970 Han Chinese women with recurrent MD. Diagnostic and other risk factor information was assessed at personal interview. Odds ratios (ORs) were calculated by logistic regression.
Compared to patients who did not endorse the cognitive trio, those who did had a greater number of DSM-IV A criteria, more individual depressive symptoms, an earlier age at onset, a greater number of episodes, and were more likely to meet diagnostic criteria for melancholia, postnatal depression, dysthymia and anxiety disorders. Hopelessness was highly related to all the suicidal symptomatology, with ORs ranging from 5.92 to 6.51. Neuroticism, stressful life events (SLEs) and a protective parental rearing style were associated with these cognitive symptoms.
During the worst episode of MD in Han Chinese women, the endorsement of the cognitive trio was associated with a worse course of depression and an increased risk of suicide. Individuals with high levels of neuroticism, many SLEs and high parental protectiveness were at increased risk for these cognitive depressive symptoms. As in Western populations, symptoms of the cognitive trio appear to play a central role in the psychopathology of MD in Chinese women.
In this paper, the conformal invariance and conserved quantities for higher-order holonomic systems are studied. Firstly, by establishing the differential equation of motion for the systems and introducing a one-parameter infinitesimal transformation group together with its infinitesimal generator vector, the determining equation of conformal invariance for the systems are provided, and the conformal factors expression are deduced. Secondly, the relation between conformal invariance and the Lie symmetry by the infinitesimal one-parameter point transformation group for the higher-order holonomic systems are deduced. Thirdly, the conserved quantities of the systems are derived using the structure equation satisfied by the gauge function. Lastly, an example of a higher-order holonomic mechanical system is discussed to illustrate these results.
The relationship between recurrent major depression (MD) in women and suicidality is complex. We investigated the extent to which patients who suffered with various forms of suicidal symptomatology can be distinguished from those subjects without such symptoms.
We examined the clinical features of the worst episode in 1970 Han Chinese women with recurrent DSM-IV MD between the ages of 30 and 60 years from across China. Student's t tests, and logistic and multiple logistic regression models were used to determine the association between suicidality and other clinical features of MD.
Suicidal symptomatology is significantly associated with a more severe form of MD, as indexed by both the number of episodes and number of MD symptoms. Patients reporting suicidal thoughts, plans or attempts experienced a significantly greater number of stressful life events. The depressive symptom most strongly associated with lifetime suicide attempt was feelings of worthlessness (odds ratio 4.25, 95% confidence interval 2.9–6.3). Excessive guilt, diminished concentration and impaired decision-making were also significantly associated with a suicide attempt.
This study contributes to the existing literature on risk factors for suicidal symptomatology in depressed women. Identifying specific depressive symptoms and co-morbid psychiatric disorders may help improve the clinical assessment of suicide risk in depressed patients. These findings could be helpful in identifying those who need more intense treatment strategies in order to prevent suicide.
Two dimensional Er3+-TeO2 thin film photonics crystals (PhCs) are fabricated. These PhCs demonstrate broadband enhancement of PL emission at near Infrared (NIR). The PhC structures are written by dual beam focused ion beam (FIB). Highly uniformed patterns with smooth surfaces are observed. A pattern resolution better than hundred nanometers is achieved. PhCs arrays with photonic lattice constants from 350 nm to 1700 nm are examined in order to optimize the PL extraction efficiency. Strong photoluminescence around 1530 nm is observed by 488-532 nm lasers pumping. A confocal microscopy with spectrometer is used to capture the broadband PL signals from individual PhC array.
The emission enhancement factor and spectral dependent extraction ratio are analyzed to find the interaction between PL lightwave and PhC structures. By optimize the PhC structures, 1500 um-1560 um broadband PL is successfully converted between the PL emission layer and the external cavity. A 60 % enhancement of surface extraction efficiency is achieved when PhC with periodicity a=800 nm is applied. When photonic lattice constants a are smaller than the critical periodicity 600 nm, the PL light becomes confined inside the thin film layer. Simulation is also performed by two dimensional finite difference time domain (FDTD) calculation in order to explain the experimental observed anisotropic PL enhancements.
The broadband PL enhancement enables Er3+-TeO2 PhCs thin film as a potential light source for three dimensional integrated photonic circuits.
The high molecular weight glutenin subunits (HMW-GS) and glutenin macropolymer (GMP) in wheat grain are important characteristics that affect the quality of wheat products. Light intensity, as one of the environmental factors affecting grain yield and quality, has been studied extensively; however, little is known about its impact on HMW-GS and distribution of GMP granules in wheat grain. In the present study, two strong-gluten winter wheat cultivars with different subunit compositions were used to evaluate the effect of shading at different grain-filling stages on changes in HMW-GS and distribution of GMP granules in wheat grains. No effects of shading on initial formation time of each individual subunit were found; they responded similarly to shading with an increase in relative content, though the accumulation amount per grain of each individual subunit was decreased due to a decrease in grain weight induced by shading. Shading at different grain-filling stages, especially at the middle grain-filling stage, led to a significant increase in GMP content during grain filling; however, the proportions (by volume, number and surface area) of the larger GMP granules were increased by shading at middle and late grain-filling stages and decreased by shading at early grain-filling stage. It was also found that the content of total HMW-GS was positively correlated with volume proportions of larger GMP granules and negatively correlated with volume proportions of small GMP granules, which indicated that the pattern of response of distribution of GMP granules to shading was closely related to the regulatory effect of shading on the HMW-GS.
In Western countries, a history of major depression (MD) is associated with reports of received parenting that is low in warmth and caring and high in control and authoritarianism. Does a similar pattern exist in women in China?
Received parenting was assessed by a shortened version of the Parental Bonding Instrument (PBI) in two groups of Han Chinese women: 1970 clinically ascertained cases with recurrent MD and 2597 matched controls. MD was assessed at personal interview.
Factor analysis of the PBI revealed three factors for both mothers and fathers: warmth, protectiveness, and authoritarianism. Lower warmth and protectiveness and higher authoritarianism from both mother and father were significantly associated with risk for recurrent MD. Parental warmth was positively correlated with parental protectiveness and negatively correlated with parental authoritarianism. When examined together, paternal warmth was more strongly associated with lowered risk for MD than maternal warmth. Furthermore, paternal protectiveness was negatively and maternal protectiveness positively associated with risk for MD.
Although the structure of received parenting is very similar in China and Western countries, the association with MD is not. High parental protectiveness is generally pathogenic in Western countries but protective in China, especially when received from the father. Our results suggest that cultural factors impact on patterns of parenting and their association with MD.