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Excessive iodine can lead to goiters. However, the relationship between the water iodine concentration (WIC) and goiter rate (GR) is unclear. This study aims to explore the factors that influence children’s GR in areas with high WIC and analyse the threshold value of the GR increase associated with the WIC. According to the monitoring of the areas with high WIC in China in 2018–2020, a total of 54 050 children in eight high water iodine provinces were chosen. Drinking water, urine and edible salt samples of children were collected. The thyroid volume (Tvol) was measured. A generalised additive model (GAM) was used to analyse the relationship between the WIC and GR in children. Among the 54 050 children in areas with high WIC, the overall GR was 3·34 %, the median of water iodine concentration was 127·0 µg/l, the median of urinary iodine concentration was 318 µg/l and the non-iodised salt coverage rate (NISCR) was 63·51 %. According to the GAM analysis results, water iodine and urinary iodine are factors that influence the Tvol and GR, while the NISCR affects only the GR. When the WIC was more than 420 µg/l or the urinary iodine concentration was more than 800 µg/l, the GR increased rapidly. When the NISCR reached more than 85 %, the GR was the lowest. Thus, in areas with high WIC, WIC more than 420 µg/l may increase the risk of goiter, and the NISCR should be increased to over 85 % to avoid goiters in children.
Global warming increases the risk of pests and weeds before wintering, and decreases the grain yield of winter wheat. Therefore, the sowing date should be delayed properly. But the variety of winter wheat that can adapt to late sowing remains unclear. Here, we selected two winter wheat cultivars and evaluated four sowing date treatments on 1 October (early sowing), 8 (normal sowing), 15 (late sowing) and 22 (latest sowing) over two wheat-growing seasons at the experimental Station of Shandong Agricultural University (35°96′N, 117°06′E), Daiyue District, Taian, Shandong, China. We examined the effects of sowing date on a few traits, and found that, compared with normal sowing, though spike number decreased, grain yield was maintained above 9300 kg/ha under late and latest sowing. The main reason was that the more accumulated N from jointing to anthesis resulted in a higher grain number per spike. The higher net photosynthetic rate after anthesis, through optimizing N distribution in the canopy and increasing Rubisco content of flag leaves, improved dry matter accumulation rate and contribution ratio of vegetative organs, ultimately, ensured consistent grain weight. The grain yield of high-tillering winter wheat cultivars decreased from 9370 to 8346 kg/ha. The main reason was that spike number, accumulated N from jointing to anthesis and net photosynthetic rate decreased significantly, which reduced the dry matter accumulation rate, and only satisfied less grains to achieve consistent grain weight. Therefore, low-tillering winter wheat cultivars are more adaptable to late sowing, and can reduce the harm of global warming.
This paper explores the relationships among positive and negative work reflection during leisure time, psychological capital, and radical and incremental creativity. We collected data from 500 dyads of employees and their direct supervisors, and employed the structural equation model to test our research hypotheses. The results reveal that positive work reflection during leisure time is positively related to radical and incremental creativity, while negative work reflection during leisure time is negatively related to the two types of creativity. Our findings also suggest that psychological capital mediates the effects of positive and negative work reflection during leisure time on radical and incremental creativity.
This study aimed to identify the important capacities that were most urgently needed during emergency response and factors associated with the Centers for Disease Control and Prevention (CDC) professionals’ field coping-capacity for public health emergency.
Professional workers (N = 1854) from 40 CDC institutions were chosen using the stratified cluster random sampling method in all 13 municipalities of Heilongjiang Province, China. Descriptive analysis and multivariate logistic regression were used.
Of 10 key capacities, the 3 that were most urgently needed during emergency response fieldwork as identified by respondents were crisis communication capacity, personal protection capacity, and laboratory detection capacity. Overall, 38.1% of respondents self-rated as “poor” on their coping-capacity. The logistic regression found that proficiency in emergency preparedness planning, more practical experiences in emergency response, effectiveness in training and drills, a higher education level, and a higher professional position were significantly associated with the individual’s field coping-capacity.
This study identified CDC professionals’ most urgent capacity need and the obstructive factors and highlighted the importance of enhancing the capacity in crisis communication, personal protection, and laboratory detection. Intervention should be targeted at sufficient fund, formalized, and effective emergency training and drills, more operational technical guidance, and all-around supervision and evaluation.
We report a new pulsed chemical vapor deposition (PCVD) process to deposit nickel (Ni) and nickel carbide (Ni3Cx) thin films, using bis(1,4-di-tert-butyl-1,3-diazabutadienyl)nickel(II) precursor and either H2 gas or H2 plasma as the coreactant, at a temperature from 140 to 250 °C. All the PCVD films are fairly pure with low levels of N and O impurities. The films deposited with H2 gas at ≤200 °C are faced centered cubic-phase Ni metal films with low C content; but at ≥220 °C, another phase of rhombohedral Ni3C is formed and the C content increases. However, when H2 plasma is used, the films are always in rhombohedral Ni3C phase for the entire temperature range.
Several epidemiological studies have been performed to evaluate the association of fruit and vegetable consumption with risk of the metabolic syndrome (MetS), but the results remain controversial. Thus, we conducted a systematic meta-analysis to assess the associations of fruit or/and vegetable consumption with risk of MetS, separately.
We searched PubMed, EMBASE and Web of Science databases up to July 2017 for relevant available articles. Pooled OR with 95 % CI were calculated with the fixed- or random-effects model.
A total of nine studies for fruit consumption, nine studies for vegetable consumption and seven studies for fruit and vegetable consumption were identified as eligible for the present meta-analysis. The pooled OR (95 % CI) of MetS for the highest v. lowest category were 0·87 (0·82, 0·92; I2=46·7 %) for fruit consumption, 0·85 (0·80, 0·91; I2=0·0 %) for vegetable consumption and 0·76 (0·62, 0·93; I2=83·5 %) for fruit and vegetable consumption. In subgroup analyses stratified by continent where the study was conducted, the inverse association of fruit consumption (0·86 (0·77, 0·96)) and vegetable consumption (0·86 (0·80, 0·92)) with risk of MetS remained significant in Asia. There was no evidence of small-study effect.
Our meta-analysis indicates that fruit or/and vegetable consumption may be inversely associated with risk of MetS. It suggests that people should consume more fruits and vegetables to decrease the risk of MetS.
Early life is considered a critical period for determining long-term metabolic health. Postnatal over-nutrition may alter glucocorticoid (GC) metabolism and increase the risk of developing obesity and metabolic disorders in adulthood. Our aim was to assess the effects of the dose and timing of a fish oil diet on obesity and the expression of GC-activated enzyme 11β-hydroxysteroid dehydrogenase type 1 (HSD1) in postnatal overfed rats. Litter sizes were adjusted to three (small litter (SL)) or ten (normal litter) rats on postnatal day 3 to induce overfeeding or normal feeding. The SL rats were divided into three groups after weaning: high-dose fish oil (HFO), low-dose fish oil (LFO) and standard-diet groups. After 10 weeks, the HFO diet reduced body weight gain (16 %, P<0·05), improved glucose intolerance and decreased hyperlipaemia levels (P<0·05) in SL rats, but the LFO diet did not have any effect on the same rats. Moreover, we chose postnatal week 3 (W3), 6 (W6) and 8 (W8) as the intervention time points at which to begin the 10-week HFO diet, and found that the HFO diet improved glucose utilisation and lipid metabolism at all time points. However, body weight of SL rats was reversed to normal levels by the post-weaning intervention (461 (sem 9·1) v. 450 (sem 2·0)). 11β-HSD1 mRNA expression in the adipose tissue (49 (sem 7·5) v. 161 (sem 18·3), P<0·05) and hepatic tissue (11 (sem 0·9) v. 16 (sem 1·5), P<0·05) was decreased by the HFO diet at W3, but not at W6 or W8 (P>0·05). In conclusion, the post-weaning HFO diet could reverse adverse outcomes and decrease tissue GC activity in postnatal overfed rats.
The aim of the present work was to determine maternal and fetal outcomes of intrahepatic cholestasis of pregnancy (ICP) in twin pregnancies. All twin pregnancies delivered above 28 gestational weeks in West China Second University Hospital from January 2013 to May 2015 were included. Data on maternal demographics and obstetric complications together with fetal outcomes were collected. The risk of adverse maternal and fetal outcomes were determined in relation to ICP by crude odds ratios (OR) and adjusted ORs (aOR) with 95% confidence intervals (CI). Subgroup analysis concentrated on the effect of assisted reproductive technology (ART), ICP severity, and onset time. A total of 1,472 twin pregnancies were included, of which 362 were cholestasis patients and 677 were conceived by ART. Higher rates of preeclampsia (aOR 1.96; 95% CI 1.35, 2.85), meconium-stained amniotic fluid (aOR 3.10; 95% CI 2.10, 4.61), and preterm deliveries (aOR 3.20; 95% CI 2.35, 4.37) were observed in ICP patients. Subgroup analysis revealed higher incidences of adverse outcomes in severe and early onset ICP groups. In conclusion, adverse maternal and fetal outcomes were strongly associated with ICP in twin patients. Active management and close antenatal monitoring are needed, especially in the early onset and severe groups.
The nonlinear temporal instability of gas-surrounded planar liquid sheets, whose linear instability contains both sinuous and varicose modes, is studied. Both the weakly nonlinear analysis using a second-order perturbation expansion and the numerical simulation using a boundary integral method have been applied. Their comparison shows that the weakly nonlinear analysis can precisely predict the shapes of sheets for most of the time of disturbance evolution and qualitatively explain the instability mechanism when sheets break up. Both the first harmonics of the linear sinuous mode and linear varicose mode are varicose; they contribute to the breakup of sheets, but the first harmonic generated by the coupling between the linear sinuous and varicose modes is sinuous; it plays an important role in modulating the wave profile. The instability with various initial phase differences between the upper and lower interfaces is examined. Except for the varicose initial disturbance, the linear sinuous mode dominates in the shapes of sheets when their amplitudes grow large. Within the second-order analysis, the major modes that can cause the breakup include the linear varicose mode, the first harmonic of the linear sinuous mode and the first harmonic of the linear varicose mode. The effects of various flow parameters have been investigated. At relatively large wavenumbers where approximate analytical and numerical results agree well when sheets break up, increasing the wavenumber reduces the wave amplitude. Reducing the initial disturbance amplitude makes the first harmonic of the linear sinuous mode the dominant mode in causing the breakup. Increasing the Weber number or gas-to-liquid density ratio significantly reduces breakup time and enhances instability.
First principles studies about the influence of electric field and anisotropic oxygen vacancy on the dielectric properties of rutile titanium dioxide (TiO2) are investigated. These results demonstrate that dielectric properties of perfect TiO2 presents dependent on the low electric field that less than 5.2 MV/cm. As a comparison, the dielectric properties of defected TiO2 in (1 1 0) plane and [1 1 0] direction show more sensitive to high electric field. Further more, considering the different positions of oxygen vacancy, the oxygen vacancy locates in (1 1 0) plane of defected TiO2 appears more active to high electric field than it does in [1 1 0] direction. The effect of electric field and oxygen vacancy induce the distorted supercell structure and broken bond between the nearer oxygen atoms and titanium atoms. Moreover, the oxygen vacancy locates in (1 1 0) plane of defected TiO2 can create more potential broken bond. These results account for the difference of dielectric properties in perfect TiO2 and defected TiO2.
In this paper, we present and analyze a single interval Legendre-Gauss spectral collocation method for solving the second order nonlinear delay differential equations with variable delays. We also propose a novel algorithm for the single interval scheme and apply it to the multiple interval scheme for more efficient implementation. Numerical examples are provided to illustrate the high accuracy of the proposed methods.
Cobalt crystals with hcp or hcp/fcc mixed structure were prepared by a solvothermal process based on the dosages of N2H4·H2O and the effect of crystal structure on their magnetic properties and Congo red (CR) removal abilities was studied. To our best knowledge, it is the first report on CR removal by micrometer and submicrometer sizes of Co crystals with the best CR removal ability reaching 694.4 mg g−1. For the hcp and fcc mixed structure, the degree of mixing can be clearly observed from the high-resolution transmission electron microscopy images. The micrometer and submicrometer sizes of Co crystals will be good for magnetic separation after CR removal.
Recent studies report a correlation between excision repair cross-complementing group 2 (ERCC2) Lys751Gln polymorphism and an increased risk of lung cancer, but results are controversial and inconclusive. Thus, we conducted a comprehensive meta-analysis in order to assess the correlation between them. Our study uses an odds ratio (OR) with a 95% confidence interval (95% CI) to evaluate the strength of the association; we also performed Begg's funnel plot and the Egger's test to assess the publication bias of previous articles. Finally, our meta-analysis is comprised of 28 full studies, including 23,370 subjects (10,242 cases and 13,128 controls). Our overall research shows that ERCC2 Lys751Gln polymorphism carries an increased risk of developing lung cancer (C vs. A: OR = 1.160, 95% CI = 1.081–1.245, p = .000; CC vs. AA: OR = 1.252, 95% CI = 1.130–1.388, p = .000; CA vs. AA: OR = 1.152, 95% CI = 1.060–1.252, p = .001; CC+CA vs. AA: OR = 1.186, 95% CI = 1.089–1.292, p = .000; CC vs. CA+AA: OR = 1.196, 95% CI = 1.087–1.316, p = .000). In ethnic subgroup analyses, we find a significant risk among Caucasians (C vs. A: OR = 1.106, 95% CI = 1.048–1.166, p = .000; CC vs. AA: OR = 1.233, 95% CI = 1.103–1.378, p = .000; CC+CA vs. AA: OR = 1.113, 95% CI = 1.033–1.199, p = .005; CC vs. CA+AA: OR = 1.185, 95% CI = 1.069–1.313, p = .001) and among Asians under two genetic models (CA vs. AA: OR = 1.265, 95% CI = 1.034–1.549, p = .023; CC+CA vs. AA: OR = 1.252, 95% CI = 1.015–1.544, p = .036). These results were confirmed by similar findings, demonstrated by stratified analyses in study design and histological typing. This meta-analysis indicates that ERCC2 Lys751Gln polymorphism may lead to an increased susceptibility to lung cancer risk among Caucasians and Asians.
A second-order instability analysis has been performed for sinuous disturbances on two-dimensional planar viscous sheets moving in a stationary gas medium using a perturbation technique. The solutions of second-order interface disturbances have been derived for both temporal instability and spatial instability. It has been found that the second-order interface deformation of the fundamental sinuous wave is varicose or dilational, causing disintegration and resulting in ligaments which are interspaced by half a wavelength. The interface deformation has been presented; the breakup time for temporal instability and breakup length for spatial instability have been calculated. An increase in Weber number and gas-to-liquid density ratio extensively increases both the temporal or spatial growth rate and the second-order initial disturbance amplitude, resulting in a shorter breakup time or length, and a more distorted surface deformation. Under normal conditions, viscosity has a stabilizing effect on the first-order temporal or spatial growth rate, but it plays a dual role in the second-order disturbance amplitude. The overall effect of viscosity is minor and complicated. In the typical condition, in which the Weber number is 400 and the gas-to-liquid density ratio is 0.001, viscosity has a weak stabilizing effect when the Reynolds number is larger than 150 or smaller than 10; when the Reynolds number is between 150 and 10, viscosity has a weak destabilizing effect.
In this paper, electrical and optical emission spectrometer (OES) characteristics of an Ar/air atmospheric-pressure plasma jet (APPJ) based on the plasma needle and plasma pencil systems were investigated and analyzed. Electrical measurement results showed that the breakdown and working voltage of the jet increased with the increase of the ratio of air/Ar, and the emission intensity of Ar* significantly decreased. For the plasma needle, when the ratio of air/Ar reached 1, the OES characteristics of Ar/air were similar to those of air plasma, and the main excited species was N2*. For the plasma pencil, when a little air impurity was added in Ar, the emission intensities of N2* species will be significantly increased. Based on these two APPJ systems, photoresist materials were etched, etched results showed that the etched surface was easier to be oxidized with the addition of air into Ar. The etched surface was cleaner with pure Ar plasma with scanning substrate methods than that with the Ar/air mixture. Etched results of higher ratios of air/Ar plasma were similar to those of air plasma.
In our recent study, we first reported that mutation in vascular endothelial growth factor-A is associated with bicuspid aortic valve stenosis. However, to date no groups have explored the role of vascular endothelial growth factor-A variations in the aetiology of congenital tricuspid aortic valve stenosis.
We sequenced all eight coding exons and exon–intron boundaries of the vascular endothelial growth factor-A gene in deoxyribonucleic acid samples of a cohort of 32 sporadic patients with tricuspid aortic valve stenosis, 300 normal controls, and 103 disease controls – conotruncal defects – in order to identify sequence variants.
We identified a c.973C > T heterozygous nonsense variation in exon 6 of the vascular endothelial growth factor-A gene in a patient with an isolated tricuspid aortic valve stenosis. The c.973C > T variation, which was absent in all controls, changes a highly conserved arginine at amino acid position 325 to a stop codon (p.Arg325X) and is predicted to produce a truncated protein of 324 amino acid residues. The proband's parents had a normal cardiac phenotype; however, his father was a carrier of the p.Arg325X variation, which indicates that the p.Arg325X variation is inherited and incompletely penetrant.
We report for the first time that the p.Arg325X nonsense variation in the vascular endothelial growth factor-A gene may be associated with congenital tricuspid aortic valve stenosis.