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The present study aimed to evaluate the validity and reproducibility of a thirteen-item FFQ regarding identification of dietary conditions in a rural population in China.
A reproducibility study repeated the first FFQ (FFQ1) approximately 4 weeks later (FFQ2). A validity study evaluated the mean of three consecutive 24 h diet recalls as the reference measure.
Residents of a rural area in Henan Province, which is located in the central region of China.
A total of 295 individuals participated in the reproducibility study. In addition, 123 people agreed to participate in the validity study. Spearman’s correlation coefficients between the two FFQ ranged from 0·06 (vegetables) to 0·58 (eggs). Spearman’s correlation coefficients between the two methods of collection ranged from 0·01 for cereal to 0·49 for staple foods. The mean of the intraclass correlation coefficients of the two FFQ (FFQ1 v. FFQ2) was 0·19. Bland–Altman analysis indicated good agreement for most food groups across the range of intake for the two studies.
The study demonstrated that our FFQ design could be used as a representative tool to conduct a dietary evaluation of a rural population.
Objective: Deficits in the semantic learning strategy were observed in subjects with amnestic mild cognitive impairment (aMCI) in our previous study. In the present study, we explored the contributions of executive function and brain structure changes to the decline in the semantic learning strategy in aMCI. Methods: A neuropsychological battery was used to test memory and executive function in 96 aMCI subjects and 90 age- and gender-matched healthy controls (HCs). The semantic clustering ratio on the verbal learning test was calculated to evaluate learning strategy. Medial temporal lobe atrophy (MTA) and white matter hyperintensities (WMH) were measured on MRI with the MTA and Fazekas visual rating scales, respectively. Results: Compared to HCs, aMCI subjects had poorer performance in terms of memory, executive function, and the semantic clustering ratio (P < .001). In aMCI subjects, no significant correlation between learning strategy and executive function was observed. aMCI subjects with obvious MTA demonstrated a lower semantic clustering ratio than those without MTA (P < .001). There was no significant difference in the learning strategies between subjects with high-grade WMH and subjects with low-grade WMH. Conclusion: aMCI subjects showed obvious impairment in the semantic learning strategy, which was attributable to MTA but independent of executive dysfunction and subcortical WMH. These findings need to be further validated in large cohorts with biomarkers identified using volumetric brain measurements. (JINS, 2019, 25, 706–717)
Direct determination of barrier height (ΦBH) value between Ir and single crystal (001) hydrogen-terminated diamond with lightly boron doped has been performed using x-ray photoelectron spectroscopy technique. 70 nm Ir islands were formed on hydrogen-terminated diamond surface using anodic aluminum oxide. The ΦBH value for Ir/hydrogen-terminated diamond was −0.43 ± 0.14 eV, indicating that Ir was a suitable metal for ohmic contact with hydrogen-terminated diamond. The band diagram of Ir/hydrogen-terminated diamond was obtained. The experimental ΦBH was compared with the theoretical ΦBH in this work.
The aim of this study was to investigate the in vivo degradation mechanism and the mechanical properties of poly(lactide-co-glycolide)/beta-tricalcium phosphate (PLGA/β-TCP) composite anchors. Anchors composed of PLGA and β-TCP were implanted in the dorsal subcutaneous tissue of beagle dogs for 6, 12, 16, and 26 weeks. The degradation of the materials was evaluated by measuring the changes in thermal behavior, crystallinity, and mechanical properties. Scanning electron microscope (SEM) was used to observe the surface and longitudinal section of the material. The evaluation of mechanical strength retention and degradation properties suggest that the addition of β-TCP particles efficiently enhances their mechanical properties and thermal characteristics and delays their degradation rate. By analyzing the results of SEM, X-ray diffraction, and differential scanning calorimetry, we can infer that after 12 weeks, the connection between β-TCP and PLGA becomes less compact, which accelerates the decline of mechanical strength.
High-entropy ceramic (HEC) films refer to the carbide, boride, oxide, or nitride films of the high-entropy alloy, which have potential applications under high temperatures. In this study, we fabricated the HEC NbTiAlSiZrNx films using magnetron sputtering under various deposition atmospheres. The phase structure evolution and the mechanical properties of three HEC films under high temperatures were investigated. The HEC films demonstrated good thermal stability as well as high hardness. After annealing for 24 h at 700 °C, the films remained in an amorphous phase without obvious crystallization, and the hardness of the films declined. Nanocrystallizations occurred in films deposited at a nitrogen flow rate of 4 sccm and 8 sccm after annealing for 30 min at 900 °C and exhibited an face-centered cubic structure. HEC NbTiAlSiZrNx films have potential applications as protective coatings under high temperatures.
The Chinese Solar and Geophysical Data (CSGD) was first issued at the Beijing Astronomical Observatory, Chinese Academy of Sciences (now the headquarter of the National Astronomical Observatories, Chinese Academy of Sciences) in 1971, when China’s satellite-industry was booming. CSGD covers the observational data (observations of the sunspots, solar flares, solar radio bursts, ionospheric storm and geomagnetic storm) from a couple of domestic observatories and the forecast data. The compiler of CSGD still keeps the data exchange with other institutes worldwide. The type of the dataset includes texts, tables, figures and so on. Up to now, we have electronized all the historic archives, making them easily accessible to people who are interested in them.
To better stabilize the hydrogen-terminated surface, a diamond based metal-insulator-semiconductor field-effect transistor with Zr-Si-N dielectric layer has been investigated. On the diamond epitaxial layer grown by microwave plasma chemical vapor deposition system, Pd films were patterned as the source and drain electrodes by photolithography and electron beam evaporation methods. Then, a Zr-Si-N dielectric layer and W metal film were fabricated as the gate structure by radio frequency magnetron sputtering technique. The device illustrates p-type depletion mode, in which the threshold voltage, maximum transconductance, drain current maximum, capacitance and dielectric constant were calculated to be 3.0V, 1.27mS/mm, -5.16 mA/mm, 0.275μF/cm2 and 7.8, respectively. The result suggest that Zr-Si-N dielectric layer is shown to have the ability to protect the two-dimensional hole gas.
With increasing output of petroleum coke, the value-added exploitation of petroleum coke has become a tough problem. Preparing porous carbons is a traditional way to the value-added exploitation of petroleum coke. Here, we used a facile and efficient hard-templating strategy to synthesize mesoporous carbon with high surface area from petroleum coke. N2 adsorption analyses show that the BET specific area and pore volume of the carbons can reach up to 864 m2/g and 1.37 cm3/g, respectively. To utilize the abundant mesopores of the carbons, anthraquinone-modified mesoporous carbon was tested as an electrode material for supercapacitor applications. Electrochemical measurements demonstrated that the specific capacitance reached up to 366 F/g at the current density of 1 A/g, indicating a promising prospect of using this carbon in electrochemical energy-storage field. More importantly, the strategy used in this work can be easily modified to prepare other nano-carbon materials from petroleum coke.
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.
The ground state properties of Fe3−xCrxO4 (x = 0–3) compounds were studied using first principles calculation. Stress–strain methods were used to evaluate elastic constants of these compounds. These compounds are mechanically stable structures, because they satisfy the mechanical stability criteria. The mechanical moduli were estimated using the Voigt–Reuss–Hill approximation. The calculated bulk moduli of Fe3O4, Fe2CrO4, FeCr2O4, and Cr3O4 are 190.9 GPa, 135.5 GPa, 180.1 GPa, and 235.6 GPa, respectively. Both of anisotropic indexes and 3-D surface contour were used to illustrate the elastic anisotropy. Debye temperature and anisotropy of acoustic velocity of Fe3−xCrxO4 compounds were also investigated. The maximum Debye temperature is attributing to Cr3O4 with 507.6 K among Fe3−xCrxO4 compounds. The minimum thermal conductivity of Fe3−xCrxO4 compounds was estimated by both Clarke's model and Cahill's model. Moreover, 3-D surface contour of the anisotropic thermal conductivity of Fe3−xCrxO4 compounds was obtained based on the Clarke's model and anisotropic Young's modulus.
Petroleum coke (PC) is a low-cost and potential carbon source for electrochemical energy storage. To expand the utilization of PC in supercapacitor, PC-based activated carbons (PCACs) with heteroatoms-doped were prepared from PC by KOH chemical activation. The as-prepared carbon exhibited a high surface area (2326.4 m2/g) and hierarchical micro-mesoporous structure, resulting in a high specific capacitance (421 F/g at 1 A/g) and excellent rate performance in KOH electrolyte (217 F/g at 50 A/g). Meanwhile, to improve the high-rate capacitive performance of PCACs in H2SO4 electrolyte, functionalized activated carbon (HQ/PCAC-4) was prepared by physically adsorbing the hydroquinone (HQ) on PCACs. The HQ/PCAC-4 showed an unprecedented capacitance value of 300.2 F/g even at an ultrahigh current density of 50 A/g. In addition, the energy density of HQ/PCAC-4 in H2SO4 electrolyte reached 19.5 W h/kg. The high energy density and excellent rate performance ensured their prosperous application in high-power energy storage system.
In this paper, the recent studies of laboratory astrophysics with strong magnetic fields in China have been reviewed. On the Shenguang-II laser facility of the National Laboratory on High-Power Lasers and Physics, a laser-driven strong magnetic field up to 200 T has been achieved. The experiment was performed to model the interaction of solar wind with dayside magnetosphere. Also the low beta plasma magnetic reconnection (MR) has been studied. Theoretically, the model has been developed to deal with the atomic structures and processes in strong magnetic field. Also the study of shock wave generation in the magnetized counter-streaming plasmas is introduced.
Generally, the obvious work hardening, dynamic recrystallization (DRX), and dynamic recovery behaviors can be found during hot deformation of Ni-based superalloys. In the present study, the classical dislocation density theory is improved by introducing a new dislocation annihilation item to represent the influences of DRX on dislocation density evolution for a Ni-based superalloy. Based on the improved dislocation density theory, the peak strain corresponding to peak stress and the critical strain for initiating DRX can be determined, and the improved DRX kinetics equations and grain size evolution models are developed. The physical framework and algorithmic idea of the improved dislocation density theory are clarified. Moreover, the deformed microstructures are characterized and quantitatively correlated to validate the improved dislocation density theory. It is found that the improved dislocation density-based models can precisely characterize hot deformation and DRX behaviors for the studied superalloy under the tested conditions.
Cognition and sleep deficits occur in amnestic mild cognitive impairment (aMCI) and vascular cognitive impairment-no dementia (VCIND). However, how memory and sleep deficits differ between aMCI and VCIND remains unclear.
Fifty aMCI and 50 VCIND patients and 38 sex- and age-matched healthy controls (HCs) were administered the Hopkins Verbal Learning Test-Revised (HVLT-R), Trail Making Test-A/B (TMT-A/B), Wisconsin Card Sorting Test (WCST), Paced Auditory Serial Addition Test (PASAT), Symbol Digit Modalities Test (SDMT), Benton Judgment of Line Orientation (JLO) test, Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), and Insomnia Severity Index (ISI) to quantify cognitive deficits and subjective sleep disturbance.
Compared with VCIND patients, aMCI patients had lower HVLT-R scores for total recall (p < 0.001), delayed recall (p < 0.001) and recognition (p = 0.001), and for total-recall (p = 0.002) and delayed-recall (p < 0.001) semantic clustering ratios (SCRs). However, VCIND patients exhibited more obvious executive dysfunction (TMT-A, p < 0.001; TMT-B, p < 0.001; WCST, p < 0.001), lower information processing speed (PASAT, p = 0.003; SDMT, p < 0.001), and more severe sleep disturbance (PSQI, p < 0.001; ESS, p < 0.001; ISI, p < 0.001). Additionally, sleep quality and efficiency were related to total and delayed recall (all r values from −0.31 to −0.60, p < 0.05) in aMCI and VCIND.
aMCI and VCIND differ in cognitive function, memory strategy and sleep impairment; these characteristics are helpful to identify and distinguish patients with very early cognitive impairment. Our results also suggest that memory deficits are associated with sleep disturbance in aMCI and VCIND.
Charged particle diagnostics is one of the required techniques for implosion areal density diagnostics at the SG-III facility. Several proton spectrometers are under development, and some preliminary areal density diagnostics have been carried out. The response of the key detector, CR39, to charged particles was investigated in detail. A new track profile simulation code based on a semi-empirical model was developed. The energy response of the CR39 detector was calibrated with the accelerator protons and alphas from a 241Am source. A proton spectrometer based on the filtered CR39 detector was developed, and D–D primary proton measurements were implemented. A step range filter spectrometer was developed, and preliminary areal density diagnostics was carried out. A wedged range filter spectrometer array made of Si with a higher resolution was designed and developed at the SG-III facility. A particle response simulation code by the Monte Carlo method and a spectra unfolding code were developed. The capability was evaluated in detail by simulations.
This is a case-control study to investigate the prevalence, characteristics, and risk factors of pain in patients with Parkinson's disease (PD).
A total of 200 PD patients from eastern China were enrolled in our study. Accordingly, 200 healthy elderly adults were recruited as controls. The characteristics of pain were collected by using the Visual Analog Scale, Brief Pain Inventory (BPI), SF-36 Bodily Pain Scale, Unified Parkinson's Disease Rating Scale, Hoehn–Yahr Scale (H-Y), Hamilton Depression Scale, and Leeds Assessment of Neuropathic Symptoms and Signs.
Of the 200 PD patients, pain was complained by 106 patients (53%). According to the SF-36 Bodily Pain Scale, pain morbidity in PD patients was significantly higher than in the control group. The average pain during last 24 h measured by the BPI was 2.67. About 76% of PD patients were found to have one pain type, 21.7% were having two pain types, and 1.9% had three pain types. Further, 69.8% of these patients were presented with musculoskeletal pain, 4.7% with dystonic pain, 22.6% with radicular-neuropathic pain, 20.8% with central neuropathic pain, and 9.4% with akathisia pain. The onset age and depression were the most significant predictors of pain in PD patients (p < 0.05). However, there was no significant association between pain and gender, age, disease duration, or severity of the disease. Only 5.7% of PD patients with pain received treatment in this study.
Pain is frequent and disabling, independent of demographic and clinical variables, and is significantly more common in PD patients.
X-ray powder diffraction data for piperaquine, C29H32Cl2N6, are reported [a = 15.8865(1) Å, b = 12.5975(3) Å, c = 13.2647(3) Å, β = 91.2890(1)°, unit-cell volume V = 2654.02 Å3, Z = 4, and space group P21/n]. All measured lines were indexed and are consistent with the P21/n space group. No detectable impurities were observed.
Seed protein content is one of the most important traits controlled by quantitative trait loci (QTLs) in soybean. In this study, a Glycine soja accession (ZYD2738) was crossed with two elite cultivars Jidou 12 and Jidou 9 separately and subsequently the resulting F2:3 populations were used to identify QTLs associated with seed protein content. Protein contents in either population appeared to have a normal distribution with transgressive segregation. A total of five QTLs associated with high protein content were identified and mapped to chromosomes 2, 6, 13, 18 and 20, respectively. Of these QTLs, three (qPRO_2_1, qPRO_13_1 and qPRO_20_1) were identified in the same region in both the populations, whereas the other two (qPRO_6_1 and qPRO_18_1) were mapped in two different regions. qPRO_2_1 appears to be a novel protein QTL. qPRO_6_1, qPRO_18_1 and qPRO_20_1 had additive effects on seed protein content, while qPRO_13_1 had an over-dominant effect on seed protein content. These QTLs and their linked markers could serve as effective tools for marker-assisted selection to increase seed protein content.
Introduction. The Chinese jujube
tree always presents some unfavorable performances because its vegetative
growth is very vigorous. Our study was conducted to apply root pruning to
test whether it can effectively inhibit the vigorous vegetative growth
by regulating the competitive ability of the root system for water
and nutrients. Materials and methods. For our experiment,
roots were cut at three different distances from the trunk (light,
moderate and severe root pruning) on both inter-row sides of jujube
trees to the depth of 20 cm. Roots of control jujube trees were
not pruned. Then we determined for three years the competitive indicators
of Chinese jujube trees including the length, number and thickness
of primary branches; photosynthetic characteristics and nutrient
concentrations of leaves; hormone contents in the jujube head, flower
number and fruiting percentage, yield, and fruit quality. Results
and discussion. In the early stage after root treatment,
root pruning decreased lots of indicators such as concentrations
of nitrogen, phosphorus, and potassium in leaves, photosynthesis, transpiration,
stomatal conductance, and intercellular CO2 concentration
of leaves, relative to the same indicators as the control group. With
the gradual emergence of new roots, these indexes appeared to have adverse
patterns with respect to those in the early stage after root pruning. Compared
with the control, root pruning significantly decreased the length
and number of primary branches and flower number, but thickened
primary branches, enhanced fruiting percentage and increased the amount
of ethylene release of the jujube head in the whole experiment.
Fruit quality was improved with root pruning, as indicated by increases
in vitamin C and total sugar and a decrease in titrable acidity.
No effects of root pruning were noticed on yield. From our results,
we conclude that the removal of the root system at a distance of
three times the trunk diameter (severe pruning) from the trunk is
the most effective in regulating the competitive ability of the
Chinese jujube tree.