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To investigate the hypothesis that folic acid supplementation and dietary folate intake before conception and during pregnancy reduce the risk of small for gestational age (SGA) and to examine the joint effect of folic acid supplementation and dietary folate intake on the risk of SGA.
Participants were interviewed by trained study interviewers using a standardized and structured questionnaire. Information on birth outcomes and maternal complications was abstracted from medical records and dietary information was collected via a semi-quantitative FFQ before conception and during pregnancy.
A birth cohort data analysis using the 2010–2012 Gansu Provincial Maternity and Child Care Hospital.
Women (n 8758) and their children enrolled in the study.
Folic acid supplementation was associated with a reduced risk of SGA (OR = 0·72, 95 % CI 0·60, 0·86), with the reduced risk seen mainly for SGA at ≥37 weeks of gestational age (OR = 0·70, 95 % CI 0·58, 0·85) and nulliparous SGA (OR = 0·67, 95 % CI 0·54, 0·84). There was no significant association between dietary folate intake and SGA risk.
Our study suggested that folic acid supplementation was associated with a reduced risk of SGA and the risk varied by preterm status and parity.
Heading errors caused by gyroscope drift affect the positioning precision of pedestrian dead reckoning, and these errors are even greater for smartphone-based reckoning. In this study, an optimised improved heuristic drift elimination (O-iHDE) method is proposed to correct the heading errors on a smartphone gyroscope. Based on an analysis of the improved heuristic drift elimination (iHDE) and enhanced improved heuristic drift elimination (E-iHDE) algorithms, the quaternion method is used to update the attitude and angle threshold judgement conditions, and a method for correcting the quaternion is added to eliminate the heading errors caused by random gyro errors. The analysis of multiple sets of experiments shows that the new method improves the ability to discern and correct the walking route, and the heading accuracy is improved by more than 90%, which extends the effective operation time of pedestrian dead reckoning positioning based on the step-by-step system.
The microbiota–gut–brain axis, especially the microbial tryptophan (Trp) biosynthesis and metabolism pathway (MiTBamp), may play a critical role in the pathogenesis of major depressive disorder (MDD). However, studies on the MiTBamp in MDD are lacking. The aim of the present study was to analyze the gut microbiota composition and the MiTBamp in MDD patients.
We performed shotgun metagenomic sequencing of stool samples from 26 MDD patients and 29 healthy controls (HCs). In addition to the microbiota community and the MiTBamp analyses, we also built a classification based on the Random Forests (RF) and Boruta algorithm to identify the gut microbiota as biomarkers for MDD.
The Bacteroidetes abundance was strongly reduced whereas that of Actinobacteria was significantly increased in the MDD patients compared with the abundance in the HCs. Most noteworthy, the MDD patients had increased levels of Bifidobacterium, which is commonly used as a probiotic. Four Kyoto Encyclopedia of Genes and Genomes (KEGG) orthologies (KOs) (K01817, K11358, K01626, K01667) abundances in the MiTBamp were significantly lower in the MDD group. Furthermore, we found a negative correlation between the K01626 abundance and the HAMD scores in the MDD group. Finally, RF classification at the genus level can achieve an area under the receiver operating characteristic curve of 0.890.
The present findings enabled a better understanding of the changes in gut microbiota and the related Trp pathway in MDD. Alterations of the gut microbiota may have the potential as biomarkers for distinguishing MDD patients form HCs.
Underground Nuclear Astrophysics in China (JUNA) will take the advantage of the ultra-low background in Jinping underground lab. High current accelerator with an ECR source and detectors were commissioned. JUNA plans to study directly a number of nuclear reactions important to hydrostatic stellar evolution at their relevant stellar energies. At the first period, JUNA aims at the direct measurements of 25Mg(p,γ)26 Al, 19F(p,α) 16 O, 13C(α, n) 16O and 12C(α,γ) 16O near the Gamow window. The current progress of JUNA will be given.
Low urinary iodine concentration (UIC) is associated with dyslipidaemia in adults but is not well characterised in adolescents. Because dyslipidaemia is a cardiovascular risk factor, identifying such an association in adolescents would allow for the prescription of appropriate measures to maintain cardiovascular health. The present study addresses this question using data in the 2001–2012 National Health and Nutrition Examination Survey for 1692 adolescents aged 12–19 years. Primary outcomes were UIC, cardiometabolic risk factors and dyslipidaemia. Data for subjects categorised by low and normal UIC and by sex were analysed by univariate and multivariate logistic regression. Treating UIC as the independent variable, physical activity level, apoB and lipid profiles differed significantly between subjects with low and normal UIC. Subjects with low UIC had a significantly greater risk of elevated total cholesterol (TC) (95 % CI 1·37, 2·81), elevated non-HDL (95 % CI 1·33, 2·76) and elevated LDL (95 % CI 1·83, 4·19) compared with those with normal UIC. Treating UIC as a dependent variable, the risk of low UIC was significantly greater in those with higher apoB (95 % CI 1·52, 19·08), elevated TC (≥4·4mmol/l) (95 % CI 1·37, 2·81) and elevated non-HDL (≥3·11mmol/l) (95 % CI 1·33, 2·76) than in those with normal UIC. These results show that male and female adolescents with low UIC tend to be at greater risk of dyslipidaemia and abnormal cardiometabolic biomarkers, though the specific abnormal parameters differed between sexes. These results may help to identify youth who would benefit from interventions to improve their cardiometabolic risk.
We present laboratory measurement and theoretical analysis of silicon K-shell lines in plasmas produced by Shenguang II laser facility, and discuss the application of line ratios to diagnose the electron density and temperature of laser plasmas. Two types of shots were carried out to interpret silicon plasma spectra under two conditions, and the spectra from 6.6 Å to 6.85 Å were measured. The radiative-collisional code based on the flexible atomic code (RCF) is used to identify the lines, and it also well simulates the experimental spectra. Satellite lines, which are populated by dielectron capture and large radiative decay rate, influence the spectrum profile significantly. Because of the blending of lines, the traditional
value are not applicable in diagnosing electron temperature and density of plasma. We take the contribution of satellite lines into the calculation of line ratios of He-
lines, and discuss their relations with the electron temperature and density.
Neurosyphilis (NS) may present with neuropsychiatric disorders characterized by cognitive impairment, personality disorders, and confusion, among others. Very few studies have focused on neuropsychiatric disorders secondary to NS in elderly people.
A retrospective chart review was performed to characterize the psychiatric findings, clinical signs and symptoms, laboratory findings, and brain magnetic resonance imaging results of ten elderly inpatients with NS.
In these ten patients, the most common presenting symptoms included a wide variety of psychiatric manifestations. The serum rapid plasma regain (RPR) and Treponema pallidum particle agglutination assay (TPPA) of the ten patients were positive, with positive CSF TPPA and RPR rates of 100% and 60%, respectively. In addition, 90% of the patients demonstrated abnormal imaging, including cerebral atrophy, infarct ischemic stroke, and hydrocephalus.
Our findings support the importance of serological tests for syphilis as a routine component of the evaluation of patients with clinically evident neurological or psychiatric symptoms. If the serology is positive, all of the patients should be examined with a lumbar puncture. Moreover, psychiatric illnesses secondary to NS in the elderly also deserve medical attention.
Pearlitic transformation in an ultrafine-grained (UFG) hypereutectoid steel was investigated. The steel was a plain carbon steel containing 1.0 wt% C and very few other elements. The UFG samples were prepared by thermomechanical treatment, and an average grain size of approximately 1 μm was achieved. The pearlitic transformation was conducted by heating the UFG samples at 1023 K for different times and then cooling in air. A new pearlitic transformation phenomenon was observed: traditional lamellar pearlite can be observed only when the grain size increases to a dimension larger than approximately 4 μm, which is a critical value. When grain size is smaller than this value, the pearlitic transformation occurs in the form of divorced eutectoid, and the microstructure is the ferrite matrix with granular cementite. This research indicates that grain size has a great influence on pearlitic transformation by shortening the diffusion distance and increasing the diffusion rate of carbon atoms in the UFG steel.
This paper introduces the design and kinematic analysis of a 5-DOF (multiple degree of freedom) hybrid-driven MR (Magnetic Resonance) compatible robot for prostate brachytherapy. It can slip the leash of template and rely on the high precise of MR imaging. After a brief introduction on design requirements of MR compatible robot, a description of our robot structure, material selection, hybrid-driven, and control architecture are presented. Secondly, the forward kinematics equations are obtained according to the equivalent diagram of this robot, and the actual workspace can be outlined. This will help the designer to determine whether this robot can be operated in the MR core without intervention with patient. And then, the inverse kinematics equations combined with trajectory planning are used to calculate the actuators movement. This will help the control system to manipulate the robotic accurately. Finally, vision based experiments on phantoms are used to verify the mechanism precision. As the results shown, the needle tip precision of mechanism is 0.9 mm in the general lab environment.
Introduction. Root-knot nematodes (Meloidogyne sp.) cause significant economic damage to Prunus species in China. One of the most economical and environmentally sustainable methods to reduce the impact of root-knot nematodes is the use of resistant rootstock cultivars. Our aim was to examine resistance to M. incognita and its mechanisms. Materials and methods. Four rootstocks were assessed: Tsukuba-4 (P. persica), Tsukuba-5 (P. persica), Nanking cherry (P. tomentosa) and wild peach (P. persica). The susceptible tomato (Lycopersicon esculentum Mill.) cultivar ‘Baiguoqiangfeng’ was used as a positive control. Results. Nematodes did not penetrate roots of Tsukuba-4 and Tsukuba-5, which were considered to be immune varieties. Nanking cherry was highly resistant to M. incognita, whereas wild peach was susceptible. Conclusion. The differences in resistance among the rootstocks were not attributed to differences in effects of root diffusates, but were related to the different structural organizations of the root tips. The epidermal structure of Tsukuba-4 and Tsukuba-5 completely prevented the penetration of second-stage juveniles of M. incognita (J2). In Nanking cherry, penetration of J2 juveniles was reduced, and the development of nematodes from the J2 to female stage was delayed.
For the first time, we discuss the compatibility of stress proximity technique (SPT) with dual stress liner (DSL) in high-κ/metal gate (HK/MG) technology. The short-channel mobility enhancement and the drive current improvement brought by SPT have been demonstrated at 32nm technology node. With maintained short channel control and threshold voltage roll-off characteristics, SPT has achieved 7% drive current improvement for both nFET and pFET from the optimization of SPT with DSL.
The present study was designed to evaluate the feasibility of producing pig transgenic blastocysts expressing enhanced green fluorescent protein (GFP) and to examine the effects of shape and preparation methods of donor cells on in vitro developmental ability of pig nuclear transferred embryos (NTEs). In experiment 1, the effect of GFP transfection on development of pig NTEs was evaluated. The cleavage and blastocyst rates showed no significant difference between NTEs derived from transfected and non-transfected donors. In experiment 2, the effect of different nuclear donor preparation methods on in vitro development of NTEs was examined. The cleavage rate showed no statistically significant differences among three preparation methods. The blastocyst rates of donor cells treated once at −4 °C and those of freshly digested cells were similar to each other (26.3% vs 17.9%). The lowest blastocyst rates (5.88%) were observed when cells cryopreserved at −196 °C were used as donors. In experiment 3, the effect of different cell cycle synchronization methods on the in vitro development potential of pig NTEs was evaluated. The cleavage rate of NTEs derived from cycling cells was much better than that of NTEs derived from serum-starved cells (64.4% vs 50.5%, p < 0.05), but no significant difference was observed between the the blastocyst rates of the two groups. In experiment 4, the effect of different shapes of cultured fibroblast cells on the in vitro development of pig NTEs was examined. The fusion rate for couplets derived from rough cells was poorer than that observed in couplets derived from round smooth cells (47.8% vs 76.8%, p < 0.05). However, there were no significant differences observed in the cleavage rate and blastocyst rate. In conclusion, the present study indicated that (i) refrigerated pig GFP-transfected cells could be used as donors in nuclear transfer and these NTEs could be effectively developed to blastocyst stage; (ii) serum starvation of GFP-transfected cells is not required for preimplantation development of pig NTEs; and (iii) a rough surface of GFP-transfected donor cells affects fusion rate negatively but has no influence on the cleavage rate or blastocyst rate of pig NTEs.
Nano-sized TiO2 particles are of interest for many applications, including use as photocatalysts and in heat transfer fluids (nanofluids). In the present study, TiO2 nanoparticles with controllable phase and particle size have been obtained through homogeneous gas-phase nucleation using chemical vapor condensation (CVC). The phase and particle size of TiO2 nanoparticles under various processing conditions have been characterized using x-ray diffraction and transmission electron microscopy. Chamber temperature and pressure were found to be two key parameters affecting particle phase and size. Pure anatase phase was observed for synthesis temperatures as low as 600 °C with chamber pressure varying from 20-50 Torr. When the furnace temperature was increased to 1000 °C at a pressure of 50 Torr, a mixture of anatase and rutile phases was observed, with the predominant phase being anatase. The average particle size under all the experimental conditions was observed to be less than 20 nm.
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