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The effects of macronutrient intake on obesity are controversial. This research aims to investigate the associations between macronutrient intake and new-onset overweight/obesity. The relationship between the consumption of carbohydrate and total fat and obesity was assessed by the multivariable Cox model in this 11-year cohort, which included 6612 adults (3291 men and 3321 women) who were free of overweight and obesity at baseline. The dietary intake was recorded using a 24-h recall method for three consecutive days. Moreover, substitution models were developed to distinguish the effects of macronutrient composition alteration from energy intake modification. During 7·5 person years (interquartile range 4·3, 10·8) of follow-up, 1807 participants became overweight or obese. After adjusting for risk factors, the hazard ratio (HR) of overweight/obesity in extreme quintiles of fat was 1·48 (quintile 5 v. quintile 1, 95 % CI 1·16, 1·89; Ptrend = 0·02) in women. Additionally, replacing 5 % of energy from carbohydrate with equivalent energy from fat was associated with an estimated 4·3 % (HR 1·043, 95 % CI 1·007, 1·081) increase in overweight/obesity in women. Moreover, dietary carbohydrate was inversely associated with overweight/obesity (quintile 5 v. quintile 1, HR 0·70, 95 % CI 0·55, 0·89; Ptrend = 0·02) in women. Total fat was related to a higher risk of overweight/obesity, whereas high carbohydrate intake was related to a lower risk of overweight/obesity in women, which was not observed in men.
Only 30% or fewer of individuals at clinical high risk (CHR) convert to full psychosis within 2 years. Efforts are thus underway to refine risk identification strategies to increase their predictive power. Our objective was to develop and validate the predictive accuracy and individualized risk components of a mobile app-based psychosis risk calculator (RC) in a CHR sample from the SHARP (ShangHai At Risk for Psychosis) program.
In total, 400 CHR individuals were identified by the Chinese version of the Structured Interview for Prodromal Syndromes. In the first phase of 300 CHR individuals, 196 subjects (65.3%) who completed neurocognitive assessments and had at least a 2-year follow-up assessment were included in the construction of an RC for psychosis. In the second phase of the SHARP sample of 100 subjects, 93 with data integrity were included to validate the performance of the SHARP-RC.
The SHARP-RC showed good discrimination of subsequent transition to psychosis with an AUC of 0.78 (p < 0.001). The individualized risk generated by the SHARP-RC provided a solid estimation of conversion in the independent validation sample, with an AUC of 0.80 (p = 0.003). A risk estimate of 20% or higher had excellent sensitivity (84%) and moderate specificity (63%) for the prediction of psychosis. The relative contribution of individual risk components can be simultaneously generated. The mobile app-based SHARP-RC was developed as a convenient tool for individualized psychosis risk appraisal.
The SHARP-RC provides a practical tool not only for assessing the probability that an individual at CHR will develop full psychosis, but also personal risk components that might be targeted in early intervention.
After MRI studies suggested the efficacy of ethyl-EPA in reducing the progressive brain atrophy in Huntington disease (HD), trials were conducted to test its efficacy as a treatment for HD. Trials that continued for 6 months did not find any significant improvement, urging discontinuation of the drug. However, trials that continued for 12 months indicated improvement of motor functions in these patients.
We searched 12 electronic databases to find randomised clinical trials relevant to our inclusion criteria. After screening, only five papers were included. Continuous and binary variables were analysed to compute the pooled mean difference (MD) and risk ratio (RR), respectively. Quality effect model meta-analysis was used as a post hoc analysis for studies at 12 months.
Meta-analysis indicated that ethyl-eicosapentaenoic acid (EPA) has no significant effect on any scale of HD at 6 months. At 12 months, two studies suggested significant improvements of the Total Motor Score and Total Motor Score–4 in both fixed and quality effect models [MD = −2.720, 95% CI (−4.76, –.68), p = 0.009; MD = −2.225, 95% CI (−3.842, −0.607), p = 0.007], respectively. Maximal chorea score showed significant results [MD = −1.013, 95% CI (−1.793, −0.233), p = 0.011] in only fixed-effect model, while no improvement was detected for Stroop colour naming test or symbol digit modality.
Meta-analysis indicated a significant improvement of motor scores only after 12 months. These results should be interpreted cautiously because only two studies had assessed the efficacy of ethyl-EPA after 12 months with one of them having a 6-month open-label phase.
The High-degree Cubature Kalman Filter (HCKF) is proposed as a novel methodology based on the arbitrary degree spherical rule, which can achieve better performance than the traditional Kalman filter. However, it also has a large calculation burden when used in a high-dimension and high-degree of accuracy estimation system. The number of sampling points of an HCKF increases polynomially with increasing state-space dimensions, which further increases the calculation burden. The reduction of the number of the state-space dimensions is the main contribution of this study. A strategy for HCKF based on the partitioning of the state-space and orthogonal principle is introduced, referred to as the Multiple Robust HCKF (MRHCKF). It is shown that this technique can effectively reduce the calculation burden for the high-dimension system with robust performance. Numerical simulations are performed for the example of high-dimension relative position and attitude estimation to show that the proposed method can obtain nearly the same performance as the HCKF, while drastically reducing computational complexity.
Combining density functional theory calculations and temperature programmed desorption (TPD) experiments, the adsorption behavior of various sulfur containing compounds, including C2H5SH, CH3SCH3, tetrahydrothiophene, thiophene, benzothiophene, dibenzothiophene, and their derivatives on the coordinately unsaturated sites of Mo27Sx model nanoparticles, are studied systematically. Sulfur molecules with aromaticity prefer flat adsorption than perpendicular adsorption. The adsorption of nonaromatic molecules is stronger than the perpendicular adsorption of aromatic molecules, but weaker than the flat adsorption of them. With gradual hydrogenation (HYD), the binding affinity in the perpendicular adsorption modes increases, while in flat adsorption modes it increases first, then decreases. Significant steric effects on the adsorption of dimethyldibenzothiophene were revealed in perpendicular adsorption modes. The steric effect, besides weakening adsorption, could also activate the S–C bonds through a compensation effect. Finally, by comparing the theoretical adsorption energies with the TPD results, we suggest that HYD and direct-desulfurization path may happen simultaneously, but on different active sites.
Si-TiN alloys are attractive for use as negative electrodes in Li-ion cells because of the high conductivity, low electrolyte reactivity, and thermal stability of TiN. Here it is shown that Si-TiN alloys with high Si content can surprisingly be made by simply ball milling Si and Ti powders in N2(g); a reaction not predicted by thermodynamics. This offers a low-cost and simple method of synthesizing these attractive materials. The resulting alloys have smaller grain sizes than Si-TiN made by ball milling Si and TiN directly, giving them high thermal stability and improved cycling characteristics in Li cells.
This paper proposes a detailed investigation on the new neural-based feed-forward PID direct force control (FNN-PID-DF) approach applied to a highly nonlinear 2-axes pneumatic artificial muscle (PAM) manipulator in order to ameliorate its force output performance. Founded on the novel inverse neural NARX model dynamically identified to learn well all nonlinear characteristics of the contact force dynamics of the 2-axes PAM-based manipulator, the novel proposed neural FNN-PID-DF force controller is innovatively implemented in order to directly force control the 2-axes PAM robot system used as a rehabilitation device subjected to internal systematic interactions and external contact force deviations. The performance of the experimental tests has proven the advantages and merits of the new force control method compared to the classical PID force control method. The new neural FNN-PID-DF force controller guides the wrist/hand of subject/patient to successfully generate the predefined desired force values.
This work designed a facile preparation for an SiO2/C composite as the anode material for lithium ion battery. Both SiO2 and carbon are amorphous. SiO2 and carbon are mixed uniformly. The SiO2/C composite shows high specific capacity, cycle stability, and rate capability in lithium ion battery charge–discharge test. A stable reversible capacity of 1024 mA h/g at the current density of 100 mA/g is reached. The capacity retains 83% after 100 cycles. The uniform mixture of SiO2 and carbon leads to reduced volume change during the lithiation and delithiation of SiO2, together with the amorphous nature of SiO2 explains the high cycling stability. The carbon coating is a key factor for the high capacity and stability due to the increased electrical conductivity and reduced volume change. The resistance of the solid electrolyte interface film and charge transfer resistance of the SiO2/C composite are much smaller than those of pure carbon, which is a direct proof of the improved conductivity of the material by the carbon coating.
In this paper, field effect transistors (FET) based on different kinds of non-graphene materials are introduced, which are MoS2, WSe2 and black phosphorus (BP). Those devices have their unique features in fabrication process compared with conventional FETs. Among them, MoS2 FET shows better electrical characteristics by applying a SiO2 protective layer; WSe2 FET is fabricated based on a new low pressure chemical vapor deposition (LPCVD) method; BP FET acquires high on/off ratio and high hole mobility by using a simple dry transfer method. Those novel non-graphene materials inspire new design and fabrication process of basic logic device.
The purpose of the present study was to examine the influence of maternal pre-pregnancy BMI and gestational weight gain (GWG) on initiation and duration of infant breast-feeding in a prospective birth cohort study.
Breast-feeding information was collected at 1, 3, 6 and 12 months postpartum. The association of pre-pregnancy BMI and GWG with delayed lactogenesis II and termination of exclusive breast-feeding was assessed with logistic regression analysis. The risk of early termination of any breast-feeding during the first year postpartum was assessed with Cox proportional hazards models.
Urban city in China.
Women with infants from the Ma’anshan Birth Cohort Study (n 3196).
The median duration of any breast-feeding in this cohort was 7·0 months. Pre-pregnancy obese women had higher risks of delayed lactogenesis II (risk ratio=1·89; 95 % CI 1·04, 3·43) and early termination of any breast-feeding (hazard ratio=1·38; 95 % CI 1·09, 1·75) adjusted for potential maternal and infant confounders, when compared with normal-weight women. No differences in breast-feeding initiation or duration of exclusive breast-feeding according to pre-pregnancy BMI were found. Moreover, GWG was not associated with any poor breast-feeding outcomes.
The present study indicated that pre-pregnancy obesity increases the risks of delayed lactogenesis II and early termination of any breast-feeding in Chinese women.
Environmental filtering and competitive interactions are important ecological processes in community assembly. The contribution of the two processes to community assembly can be evaluated by shifts in functional diversity patterns. We examined the correlations between functional diversity of six traits (leaf chlorophyll concentration, dry matter content, size, specific leaf area, thickness and wood density) and environmental gradients (topography and soil) for 92 species in the 20-ha Dinghushan forest plot in China. A partial Mantel test showed that most of the community-weighted mean trait values changed with terrain convexity and soil fertility, which implied that environmental filtering was occurring. Functional diversity of many traits significantly increased with increasing terrain convexity and soil fertility, which was associated with increased light and below-ground resources respectively. These results suggest that co-occurring species are functionally convergent in regions of strong abiotic stress under the environmental filtering, but functionally divergent in more benign environments due to resource partitioning and competitive interactions. Single-trait diversity and multivariate functional diversity had different relationships with environmental factors, indicating that traits were related to different niche axes, and associated with different ecological processes, which demonstrated the importance of focusing niche axes in traits selection. Between 9% and 41% of variation in functional diversity of different traits was explained by environmental factors in stepwise multiple regression models. Terrain convexity and soil fertility were the best predictors of functional diversity, which contributed 30.5% and 29.0% of total R2 to the model. These provided essential evidence that different environmental factors had distinguishing impacts on regulating diversity of traits.
The relationship between climate, crop growth and crop yield is complicated. This study aimed to determine the ratio of CO2–C emission to grain yield, the field treatments were initiated in 2003, but the measurements for this analysis were collected during the summer maize-growing seasons of 2011 and 2012 in the North China Plain. The experiment showed that conventional tillage with straw application significantly increased grain yield and the ratio of CO2–C emission to grain yield of summer maize. The mean soil CO2–C emission rate with no tillage was significantly lower than that when conventional tillage was used; however, straw application significantly increased the soil CO2–C emission rate, irrespective of whether tillage was performed or not. This was mainly because straw application changed the soil total porosity and organic carbon content. In conclusion, the results of this study support the hypothesis that the ratio of CO2–C emission to grain yield in the North China Plain can be increased by straw application, whereas no tillage decreases this ratio.
Most long QT syndrome patients are associated with genetic mutations. We aimed to investigate the clinical and biochemical characteristics and look for genotype-based preventive implications in Chinese long QT syndrome patients.
Methods and results
We identified two missense mutations of the KCNQ1 gene in two independent Chinese families, including a previously reported mutation R380S in the C-terminus and a novel mutation W305L in the P-loop domain of the Kv7.1 channel, respectively. The proband with R380S was an 11-year-old girl who suffered a prolonged corrected QT interval of 660 ms, recurrent syncope, and sudden cardiac death, whose father was an asymptomatic carrier. The mutation W305L was detected in a 36-year-old woman with long QT syndrome and her immediate family members including the proband’s younger sister with an unexplained syncope, her son, and her elder daughter without symptoms. Metoprolol appeared to be effective in preventing arrhythmias and syncope in long QT syndrome patients with mutation W305L. Both R380S and W305L mutations led to “loss-of-function” of the Kv7.1 channel accounting for the clinical phenotypes.
We first show two missense KCNQ1 mutations – R380S and W305L – in Chinese long QT syndrome patients, resulting in the loss of protein function. Mutation W305L in the P-loop domain of the Kv7.1 may derive a pronounced benefit from β-blocker therapy in symptomatic long QT syndrome patients, whereas mutation R380S located in the C-terminus may be associated with a high risk of sudden cardiac death.
Unlike a conventional laser which utilizes mirrors or periodic structures to trap light, a random laser relies on the multiple scattering of light in a disordered gain medium for optical feedback and light confinement (see Figure 6.1) [67, 70, 528, 529]. Coherent laser emission has been generated from various random structures ranging from semiconductor nanoparticles and nanorods to polymers and organic materials. Over the past decade, random lasers have generated significant interest among researchers because of their unique applications [67, 529]. For example, specifically designed random lasers combine high radiance with low spatial coherence [357, 403], ideally suited for speckle-free, parallel, high-speed imaging, laser projection and ranging . The sensitivity of the random lasing threshold to the amount of scattering has been explored for cancerous tissue mapping [387, 389]. Moreover, the spectral fingerprint of the random structure [70, 71], the micron size , the low fabrication cost, and the robustness against surface roughness and shape deformation point to potential applications in optical tagging and identification . Since random laser cavities are formed by scattering and are much easier to fabricate compared with the mirror-based cavities, they may be applied to lasers at wavelengths where high-reflectivity mirrors are either not available or very expensive, e.g. UV laser, X-ray laser, γ-ray laser. A detailed description of random lasers can be found in Chapter 3.
However, a major limitation to device applications of random lasers is the lack of control and reproducibility of lasing modes. Namely, the frequencies and spatial locations of lasing modes are unpredictable, varying randomly from sample to sample. One way to solve this problem is to utilize pseudo-random structures, or more generally, deterministic aperiodic nanostructures (DANS) . Unlike structures generated by a random process, DANS are generated by the iteration of simple mathematical rules with a controllable degree of spatial complexity that interpolates between periodic and random systems. DANS lasers can combine the advantages of random lasers with the fabrication and design reproducibility required for optoelectronics integration.
The mesoporous and nanorods SnO2 are synthesized by controlling the state of SnCl2·2H2O precursor with SBA-15 as hard template, and the possible formation mechanisms at different assembling modes inside the ordered mesoporous silica templates are proposed. In addition, SnO2 nanoparticles are synthesized by hydrolysis depositing method. The electrochemical tests of as-prepared samples indicate that the reticular stacking structure of the nanorods would limit the Li+ ions to intercalate, but the effect of volume expansion in this case upon cycling is insignificant. The mesostructure SnO2 tends to be stable after partial structural collapse at first few cycles. And the Li+ ions can readily intercalate and de-intercalate into/from its ordered channels structure, which provides a high capacity and an improved cycle property. Although SnO2 nanoparticles deliver high capacity at an early stage, the agglomeration may induce the capacity to drop rapidly after a certain number of cycles.
A novel graphene-modified LiMnPO4 composite as a performance-improved cathode material for lithium-ion batteries has been prepared with LiH2PO4, Mn(CH3COO)2·4H2O, and graphite oxide (GO) suspension by spray-drying method. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and galvanostatic charge–discharge tests are applied to characterize these materials. The structure analysis shows that LiMnPO4 sheets with width of 100–200 nm and thickness of 20–30 nm are attached to the graphene sheets in pieces. The graphene sheets with good electrical conductivity serve as a conducting network for fast electron transfer between the active materials and charge collector, as well as buffered spaces to accommodate the volume expansion/contraction during the discharge/charge process. The electrochemical tests show that the composite cathode material could deliver a capacity of 105.1 mAh/g at 0.05 C in the voltage range of 2.5–4.4 V. Moreover, the cells showed fair good cycle ability over 50 cycles.
This paper addresses the orientation-singularity analysis and the orientationability evaluation of a special class of the Stewart–Gough parallel manipulators in which the moving and base platforms are two similar semi-symmetrical hexagons. Based on the half-angle transformation, an analytical polynomial of degree 13 that represents the orientation-singularity locus of this special class of parallel manipulators at a given position is derived. Graphical representations of the orientation-singularity locus of this class of manipulators are illustrated with examples to demonstrate the results. Based on the description of the orientation-singularity and nonsingular orientation region of this class of parallel manipulators, a performance index, referred to as orientationability, which describes the orientation capability of this class of manipulators at a given position, is introduced. A discretization algorithm is proposed for computing the orientationability of the special class of parallel manipulators at a given position in the workspace. Moreover, the effects of the design parameters and position parameters on the orientationability are also investigated in detail. Based on the orientationability performance index, another performance index, referred to as practical orientationability, representing the practical orientation capability of the manipulators at a given position, is introduced. In this performance index, singularities, the limitations of active and passive joints and link interferences are all taken into consideration. Furthermore, the practical orientationability of the special class of parallel manipulators studied here is also analyzed over several plane sections of the position-workspace in detail.
Structure and demographics in many tropical forests is changing, but the causes of these changes remain unclear. We studied 5 y (2005–2010) of species turnover, recruitment, mortality and population change data from a 20-ha subtropical forest plot in Dinghushan, China, to identify trends in forest change, and to test whether tree mortality is associated with intraspecific or interspecific competition. We found the Dinghushan forest to be more dynamic than one temperate and two tropical forests in a comparison of large, long-term forest dynamics plots. Within Dinghushan, size-class distributions were bell-shaped only for the three most dominant species and reverse J-shaped for other species. Bell-shaped population distributions can indicate a population in decline, but our data suggest that these large and long-lived species are not in decline because the pattern is driven by increasing probabilities of transition to larger size class with increasing size and fast growth in saplings. Spatially aggregated tree species distributions were common for surviving and dead individuals. Competitive associations were more frequently intraspecific than interspecific. The competition that induced tree mortality was more associated with intraspecific than interspecific interactions. Intraspecific competitive exclusion and density-dependence appear to play important roles in tree mortality in this subtropical forest.
We conduct a comparative study mainly on two types of nc-Si based solar cell structures, a-Si/a-SiGe/nc-Si triple-junction and a-Si/nc-Si double-junction. We have attained comparable initial efficiency for the both solar cell structures, 10.8∼11.8% initial total area efficiency (85 - 95W over an area of 0.79 m2). For better compatibility to our installed manufacturing equipment, we deposit a-Si and a-SiGe component cells with the existing deposition machines. Only nc-Si bottom component cells are prepared in separate deposition machines tailored for nc-Si process. Material properties of nc-Si and TCO films are also studied by Raman spectra, SEM, and AFM.
Tritium time series for precipitation in Beijing have been reconstructed for the period 1953–2002 using various methods: Guanbingjun method; trend surface analysis method; double reference curve method; triangulation method; and correlation method. By comparing the reconstructed results with the measured data of Beijing as well as data of other regions available in the IAEA GNIP database, the corresponding tritium time series have been developed for Beijing for the period 1953–2002, and the optimal time series was selected. The reconstructed result can be used for groundwater dating and related studies in Beijing as well as the surrounding areas.