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There is a dearth of data on the iodine balance studies of Chinese population. In the present study, we aimed to explore the appropriate recommended nutrient intake (RNI) of iodine based on healthy Chinese women. A 4-week study was conducted in twenty-five Chinese euthyroid women. Uniform diets with different iodine contents were provided in two different periods, in which non-iodised salt was given in the first 3 weeks, followed by 1 week of iodised salt administration. The total iodine intake from diet, water and air as well as the total iodine excretion through urine, faeces and respiration were monitored and determined. The sweat iodine loss was also considered. Moreover, the regression curve model was established between the 24 h iodine intake and 24 h iodine excretion. The 24 h iodine intake in the two periods was 194·8 (sd 62·9) and 487·1 (sd 177·3) μg/d, respectively. The 24 h iodine excretion was 130·9 (sd 39·5) and 265·4 (sd 71·8) μg/d, respectively. Both 24 h iodine intake and 24 h iodine excretion of the two periods were significantly different (all P<0·05). The iodised salt contributed approximately 62·7 % of the total daily iodine intake. Moreover, 92·3 % (277/300) of samples were in positive balance, while twenty-three cases were in negative balance. Our data show that the estimated average requirement for iodine was 110·5 μg/d. Therefore, the RNI for iodine to non-pregnant, non-lactating Chinese women was 154·7 μg/d.
Suicidal behaviours in adolescents are prevalent and multifactorial. This study was conducted to examine the associations between exposure to suicide attempt (ESA) or suicide death (ESD) and suicidal behaviours in a large sample of Chinese adolescents.
Participants included for the analysis were 11 831 adolescent students who participated in the baseline survey of the Shandong Adolescent Behavior and Health Cohort (SABHC). Participants were sampled from five middle and three high schools in three counties of Shandong province, China. A self-administered structured questionnaire was used to collect data on demographics, behavioural and emotional problems, family environment, suicidal behaviours (suicidal thought, plan and attempt), and history of ESA or death of a family member, relative, friend or close acquaintance. Based on the sources of exposure, the participants were divided into four groups: non-exposure, exposure from relatives only, exposure from friends/close acquaintances only (EFO) and exposure from both relatives and friends (ERF). Logistic regressions were used to examine the associations between ESA or ESD and suicidal behaviours.
Mean age of the participants was 14.97 ± 1.46 years and 50.9% were boys. Of the participants, 9.4% reported having ESA, and 6.6% reported having ESD. The prevalence rates of suicidal behaviours were significantly higher in adolescents who had been exposed to suicide attempt or death than those who had not. Multivariate logistic regressions showed that ESA and ESD were both significantly associated with increased risks of suicidal thought (ESA: OR = 1.96, 95% CI = 1.66–2.31; ESD: OR = 1.59, 95% CI = 1.31–1.94), plan (ESA: OR = 2.37, 95% CI = 1.84–3.05; ESD: OR = 1.62, 95% CI = 1.18–2.23) and attempt (ESA: OR = 2.73, 95% CI = 1.92–3.89; ESD: OR = 1.82, 95% CI = 1.18–2.82), respectively. When participants were exposed to suicide attempt, ERF and EFO groups had significantly higher risks of suicidal thought (ERF: OR = 2.61, 95% CI = 1.28–1.64; EFO: OR = 1.96, 95% CI = 1.64–2.36), plan (ERF: OR = 3.72, 95% CI = 2.04–6.78; EFO: OR = 2.31, 95% CI = 1.74–3.01) and attempt (ERF: OR = 4.83, 95% CI = 2.30–10.17; EFO: OR = 2.57, 95% CI = 1.73–3.81), respectively.
ESA or ESD was associated with increased risks of suicidal behaviours in adolescents. Exposure to suicidal behaviours of relatives and friends/close acquaintances appeared to have different influence on adolescent suicidal behaviours. Further research is warranted to examine the biological and psychosocial mechanisms between suicidal exposure and subsequent suicidal behaviours in adolescents.
The role of the cerebellum in obsessive-compulsive disorder (OCD) has drawn increasing attention. However, the functional connectivity between the cerebellum and the cerebral cortex has not been investigated in OCD, nor has the relationship between such functional connectivity and clinical symptoms.
A total of 27 patients with OCD and 21 healthy controls (HCs) matched on age, sex and education underwent magnetic resonance imaging (MRI). Seed-based connectivity analyses were performed to examine differences in cerebellar-cerebral connectivity in patients with OCD compared with HCs. Associations between functional connectivity and clinical features in OCD were analyzed.
Compared with HCs, OCD patients showed significantly decreased cerebellar-cerebral functional connectivity in executive control and emotion processing networks. Within the OCD group, decreased functional connectivity in an executive network spanning the right cerebellar Crus I and the inferior parietal lobule was positively correlated with symptom severity, and decreased connectivity in an emotion processing network spanning the left cerebellar lobule VI and the lingual gyrus was negatively correlated with illness duration.
Altered functional connectivity between the cerebellum and cerebral networks involved in cognitive-affective processing in patients with OCD provides further evidence for the involvement of the cerebellum in the pathophysiology of OCD, and is consistent with impairment in executive control and emotion regulation in this condition.
The pathophysiology of cognitive impairment in patients with the major depressive disorder (MDD) may involve neuroinflammation mediated by cytokines.
The aim of this study was to examine the serum interleukin-6 (IL-6) levels, sustained attention, and their association in patients with MDD.
Thirty patients with MDD and 30 healthy controls were enrolled in this case-control study. Sustained attention was measured using the Rapid Visual Information Processing (RVP) task in the Cambridge Neuropsychological Tests Automated Battery. The serum IL-6 levels of all subjects were assessed by sandwich enzyme-linked immunosorbent assays.
There were significant differences in the log10RVP total hits, log10RVP total misses, and log10RVP mean latency between patients with MDD and healthy controls (F = 6.04, p = 0.017; F = 19.77, p < 0.0001; F = 14.42, p < 0.0001, respectively). The serum levels of Log10IL-6 were significantly higher in patients with MDD than in healthy controls (F = 192.27, p < 0.0001). The log10IL-6 levels were also positively correlated with the log10RVP mean latency in patients with MDD (r = 0.45, p = 0.013). A further stepwise multivariate regression analysis indicated that the log10IL-6 levels were significantly associated with the log10RVP mean latency in patients with MDD (β = 0.31, t = 2.41, p = 0.025).
Our data suggested that increased IL-6 levels were associated with the psychopathology of MDD, and that abnormal IL-6 levels were implicated in the impairment of sustained attention in patients with MDD.
Al, Mn, Rb, Sr, Ba, Cs, Bi and Sb were measured at various depth intervals of a 41.6 m firn/ ice core drilled at an elevation of 7010 m near the top of Muztagh Ata glacier, east Pamirs (38˚17’ N, 75˚06’ E), central Asia. These data, spanning the mid-1950s to 2000, were obtained by analyzing 101 sections using a sector-field double-focusing inductively coupled plasma mass spectrometer (ICP-MS) instrument. This study provides the first time series for these metals from central Asia. Concentrations are 11.7–329 ng mL−1 for Al, 0.33–42.7 ng mL−1 for Mn, 0.42–17.8 ng mL−1 for Sr, 0.04–1.4 ng mL−1 for Rb, 0.18–10.4 ng mL−1 for Ba, 2–167 pg mL−1 for Cs, 2–51 pg mL−1 for Sb and 1–31 pg mL−1 for Bi. Large variations in metal concentrations were found during the study period. Pronounced increases in concentrations were observed for Sb and Bi from the mid-1960s to the beginning of the 1990s, suggesting increased anthropogenic sources of Sb and Bi in central Asia during the same period. However, the decrease of Sb and Bi concentrations during the mid- to late 1990s reflects a reduction in anthropogenic activities in central Asia.
Optical positions of 16 radio stars have been derived from 40 cm astrograph at Zô-Sè. The reference catalogues are AGK3 and SAO, the average mean square error of single observation is 0″.058 in the right ascension and 0″.053 in declination. The magnitude difference has no significant effect on the observations.
The Unmanned Aerial Vehicles (UAVs) become more and more popular due to various potential application fields. This paper studies the distributed leader-follower formation flight control problem of multiple UAVs with uncertain parameters for both the leader and followers. This problem has not been addressed in the literature. Most of the existing literature considers the leader-follower formation control strategy with parametric uncertainty for the followers. However, they do not take the leader parametric uncertainty into account. Meanwhile, the distributed control strategy depends on less information interactions and is more likely to avoid information conflict. The dynamic model of the UAVs is established based on the aerodynamic parameters. The establishment of the topology structure between a collection of UAVs is based on the algebraic graph theory. To handle the parametric uncertainty of the UAVs dynamics, a multivariable model reference adaptive control (MRAC) method is addressed to design the control law, which enables follower UAVs to track the leader UAV. The stability of the formation flight control system is proved by the Lyapunov theory. Simulation results show that the proposed distributed adaptive leader-following formation flight control system has stronger robustness and adaptivity than the fixed control system, as well as the existing adaptive control system.
Using phytolith analysis from a well-dated and high-resolution sediment sequence in the apex of northern Yangtze Delta, we investigate environmental changes, the rise and decline of rice exploitation and possible impacts of environment on rice exploitation during the early mid-Holocene. The phytolith sequence documents a relatively warm and dry interval during ca.9000 to 8200 cal yr BP, followed by climatic amelioration before 7200 cal yr BP. Phytolith evidence indicates that rice exploitation at the apex of northern Yangtze Delta began at 8200 cal yr BP, flourished by 7700 cal yr BP and ceased after 7400 cal yr BP. The first emergence of marine diatom species approximately 7300 cal yr BP likely indicates an accelerated sea-level rise. The apparent correlation of the initiation of rice exploitation with climatic amelioration during the early mid-Holocene suggests that climatic changes may have played an important role in facilitating rice exploitation. Both the ideal climatic conditions and stable sea level enabled flourishing rice exploitation during 8200 to 7400 cal yr BP. Although the climate remained warm and wet after 7400 cal yr BP, local sea-level rise possibly led to the termination of earlier rice exploitation at this site of the northern Yangtze Delta.
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.
For wheeled mobile robots moving in rough terrains or uncertain environments, driving failure will be encountered when trafficability failure occurs. Continuous mobility of mobile robots with special ability for overcoming driving failure on rough terrain has rarely been considered. This study was conducted using a four-wheel-steering and four-wheel-driving mobile robot equipped with a binocular visual system. First, quasi-static force analysis is carried out to understand the effects of different driving-failure modes on the mobile robot while moving on rough terrain. Secondly, to make the best of the rest of the driving force, robot configuration transformation is employed to select the optimal configuration that can overcome the driving failure. Thirdly, sliding mode control based on back-stepping is adopted to enable the robot achieve continuous trajectory tracking with visual feedback. Finally, the efficacy of the presented approach is verified by simulations and experiments.
Choline and betaine are essential nutrients involved in one-carbon metabolism and have been hypothesised to affect breast cancer risk. Functional polymorphisms in genes encoding choline-related one-carbon metabolism enzymes, including phosphatidylethanolamine N-methyltransferase (PEMT), choline dehydrogenase (CHDH) and betaine-homocysteine methyltransferase (BHMT), have important roles in choline metabolism and may thus interact with dietary choline and betaine intake to modify breast cancer risk. This study aimed to investigate the interactive effect of polymorphisms in PEMT, BHMT and CHDH genes with choline/betaine intake on breast cancer risk among Chinese women. This hospital-based case–control study consecutively recruited 570 cases with histologically confirmed breast cancer and 576 age-matched (5-year interval) controls. Choline and betaine intakes were assessed by a validated FFQ, and genotyping was conducted for PEMT rs7946, CHDH rs9001 and BHMT rs3733890. OR and 95 % CI were estimated using unconditional logistic regression. Compared with the highest quartile of choline intake, the lowest intake quartile showed a significant increased risk of breast cancer. The SNP PEMT rs7946, CHDH rs9001 and BHMT rs3733890 had no overall association with breast cancer, but a significant risk reduction was observed among postmenopausal women with AA genotype of BHMT rs3733890 (OR 0·49; 95 % CI 0·25, 0·98). Significant interactions were observed between choline intake and SNP PEMT rs7946 (Pinteraction=0·029) and BHMT rs3733890 (Pinteraction=0·006) in relation to breast cancer risk. Our results suggest that SNP PEMT rs7946 and BHMT rs3733890 may interact with choline intake on breast cancer risk.
In Chinese ancient times the Sun worship was in vogue. Mainly there were two sorts of the worship rites: 1) for rising and setting Sun; 2) for solar eclipses. Many evidences for Sun worship have been found in Chinese ancient books and bone inscriptions (Xu Zhentao et al.1985).
The everyday worship to the Sun certainly caused spontaneous observations for solar phenomena. Since the ancients only had a limited knowledge they could not understand what were these phenomena and they, however, created many wonderful myths to describe them. These myths about Solar phenomena have vividly been expressed in the works of art of the Han Dynasty recently unearthed. So analysing the works of art we may trace the original phenomena of solar activity.
Polymorphisms of genes participating in iron transportation have been associated with Alzheimer's disease (AD) risk. The association between transferrin (TF) gene rs1049296 (P570S) polymorphism and AD is controversial.
We performed meta analysis on data from 19 studies with 6310 cases and 13661 controls to reexamine the association between the TF gene rs1049296 polymorphism and AD. We applied a fixed-effects model to combine the odds ratio (OR) and 95% confidence intervals (95% CI). Egger's test was carried out to evaluate the potential publication bias.
The overall ORs with 95% CIs showed statistical association between the TF gene rs1049296 polymorphism and the risk of AD in the allele contrast, the recessive model and the dominant model for allele C2 (fixed-effects pooled OR 1.11; 95% CI 1.05 to 1.17, pooled OR 1.13; 95% CI 1.06 to 1.21, and pooled OR 1.23; 95% CI 1.03 to 1.47, respectively). In the contrast of C2C2+C2C1 vs C1C1, large heterogeneity among the Asian subgroup (p=0.041, I2= 68.6%) was observed but not among the overall population (p = 0.184, I2= 22.4%). No publication bias was observed.
The present meta analysis demonstrated that TF gene rs1049296 polymorphism is a genetic determinant of AD.
The New Vacuum Solar Telescope (NVST) is a new generation ground-based solar facility of China. One of the post-focus instruments is the multi-channel high-resolution imaging system, which is designed to simultaneously observe the dynamic gas motion in the solar photosphere and chromosphere. Since October of 2010 it has been operational in the NVST and some necessary updates were performed in past 2 years. Here we first give a general introduction of this system, and then we exhibit one near-limb observation of solar filaments obtained using this system. By this communication, we would like to show the potential ability to perform the high resolution observation of solar filaments (prominences) using the multi-channel imaging system in the NVST.
Cu0.62Zn0.38 foil was subjected to surface mechanical attrition treatment (SMAT) processing first. Growth behavior of ZnO nanostructure on the SMAT Cu0.62Zn0.38 surface during thermal oxidation was investigated in this paper. The original and SMAT Cu0.62Zn0.38 foils were thermally oxidized at 400 ~ 700 °C under various gaseous environments, including nitrogen and mixture of N2-O2 at a pressure of 1 atm. for 3 h. The oxidized specimens were characterized with a scanning electron microscope, an X-ray diffractometer and a transmission electron microscope. It is found that nanosheets are easily formed on the SMAT specimen surface. The favorable formation of nanosheets relates to twin lamellae structure of Cu0.62Zn0.38 formed during SMAT processing.
The Quanzhou (QZ) and Huacuo (HC) gabbro–granite complexes on the southeast coast of Fujian, South China, are important components of a Late Mesozoic calc-alkaline volcanic–plutonic belt in the region. The complexes provide an excellent opportunity to investigate the genetic relationships between acid and basic magmas, and their interactions within the intrusive environment. The complexes are composed mainly of monzogranite and biotite granodiorite in the QZ complex, and biotite granite in the HC complex, with lesser amounts of hornblende gabbro. Zircon U–Pb dating provides consistent crystallization ages of 109 ± 1 Ma and 108 ± 1 Ma for the QZ gabbros and monzogranites, and an age of 111 ± 1 Ma for the HC gabbro, which is contemporaneous with the spatially associated HC granites. Both the mafic and felsic intrusions in these complexes are enriched in light rare earth elements (LREEs) and large-ion lithophile elements (LILEs), and are depleted in high-field-strength elements (HFSEs; e.g. Nb and Ta). They show similarly homogeneous Sr–Nd isotopic compositions. All these factors indicate a close genetic relationship between the gabbroic and granitic rocks in the QZ and HC complexes. Although the enriched Sr–Nd isotopic signatures of the QZ and HC gabbros seemingly point to an enriched mantle source (EM-1), they have highly variable zircon Hf isotopic compositions, with εHf(t) values ranging from negative to positive (specifically –4.6 to +6.1 for the QZ gabbros and –4.8 to +11.6 for the HC gabbros). We interpret the parental basic magmas of these gabbros to have received contributions from a depleted mantle source and crustal components. Contributions from such a depleted mantle source resulted in the growth of juvenile basaltic lower crust, the partial melting of which generated the parental felsic magmas of the QZ and HC complexes. Furthermore, based on a synthesis of petrography, geochronology, elemental and isotopic geochemistry and tectonics, we propose that break-off and rollback of the Late Mesozoic subducted Palaeo-Pacific Plate triggered the upwelling of asthenospheric mantle below the coastal area of the South China Block, which induced extension of the overlying continental lithosphere, and finally initiated the large-scale Late Yanshanian magmatism in the study area.
5-hydroxytryptamine receptor 2A (5-HT2A) participates in diverse psychiatric disorders by regulating the activity of serotonin. Some previous studies have also suggested that the receptor is involved in cognitive abilities of disease groups. We hypothesize that some functional genetic variants in 5-HT2A have certain specific influences on cognitive abilities in a normal population.
To confirm this hypothesis, two polymorphisms (rs6313 and rs4941573) in 5-HT2A were selected, and a population-based study was performed in a young healthy Chinese Han cohort.
The results indicated that the rs6313 and rs4941573 were associated with touching blocks and mental rotation-3D error ratio in males, and the rs4941573 was associated with visuo-spatial working memory in the whole cohort.
All the findings suggest that 5-HT2A participates in human spatial cognitive abilities and spatial working memory.
The quasi-breakdown (QB) in ultra thin gate oxide is investigated through the observation of defect generation during high field F-N stress and substrate hot hole and hot electron stresses. The interface trap density increases during stress and reaches to a same critical amount at the onset point of QB regardless of stress current density and stressing carrier type. The experiments also show that hot carriers are much more effective to trigger QB than F-N electrons at the same current level. This can be ascribed to the fact that hot carrier has much higher interface state generation rate than F-N electron does. All results consistently support the interface damage model for the QB occurrence.
The genetic diversities of 72 individuals from three wild Lenok populations of Mudanjiang River (MD), Yalujiang River (YL) and Wusulijiang River (WSL) in the northeast of China were analysed using amplified fragment length polymorphism (AFLP) markers. The results showed that 541 polymorphic loci out of 559 were amplified by 12 primer pairs and the percentage of polymorphic loci was 96.78%. Shannon indices for the MD, YL and WSL populations were 0.3988±0.2913, 0.3254±0.3037, 0.2125±0.2862, respectively, and Nei's gene diversity indices were 0.2737±0.2062, 0.2229±0.2129, 0.1446±0.1985, respectively. The average total genetic diversity (Ht) was 0.3512±0.0.0208 and the average genetic diversity within populations (Hs) was 0.2137±0.0152. Among the three populations, the average genetic distance (Dst) was 0.1375 and the gene differentiation coefficient (Gst) was 0.3914. The genetic diversity was 60.85% within populations and 39.15% among populations. The gene flow index (Nm) was 0.7776. The analysis of molecular variance (AMOVA) indicated that the average fixation index (Fst) was 0.55336. The variance was 55.16% within populations and 44.84% among populations. The highest polymorphism ratio was in the MD group and the lowest in the WSL group.
To investigate the wheat transcriptional profile under drought stress, a drought-tolerant variety of wheat (Triticum aestivum), Hanxuan 10, was treated with polyethylene glycol (PEG6000) and samples were collected at 0, 1, 6 and 24 h. Complementary DNA was labelled with fluorescent dye and hybridized with the BGI-RiceChip, a whole genome rice gene chip platform, which contains over 60 000 oligos based on the rice genome sequence. Data analysis detected 166, 207 and 328 differentially expressed genes (DGs), respectively, at 1, 6 and 24 h, indicating that the number of DGs increased with the length of the PEG treatment. Functional category analysis showed that the number of DGs related to energy metabolism pathways increased – 4.2%, 8.2% and 16.8%, respectively, as a proportion of the total number of DGs. Most of the photosynthesis-related genes were up-regulated. It is interesting to note that Psbr and ribulose-bisphosphate carboxylase (Rubisco)-coding genes were down-regulated, suggesting their potential role in the response to drought tolerance.