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Highly dense zirconia dental ceramic coatings were fabricated by aqueous electrophoretic deposition (EPD) and subsequently sintered between 1250 and 1450 °C. Microstructural examination revealed that aqueous EPDZrO2 coatings possessed a tetragonal phase structure and the grain size increased with increasing sintering temperature. Nanoindentation study proved that the aqueous EPDZrO2 coating also had excellent mechanical properties. The effect of different applied loads on hardness and elastic modulus of the 1350 °C-sintered sample at room temperature was investigated by the method of progressive multicycle measurement nanoindentation. The simulative experiment proved that hardness of aqueous EPDZrO2 exhibited reverse indentation size effect (ISE) behavior and then displayed the normal ISE response. The analysis indicates that the reverse ISE is attributed to the relaxation of surface stresses resulting from indentation cracks at small loads and normal ISE is caused by geometrically necessary dislocations. The tetragonal–monoclinic stress-induced phase transformation during nanoindentation is the primary cause of dental zirconia failures.
Previous studies in China showed large sex differences in childhood overweight and obesity (OW/OB) rates. However, limited research has examined the cause of these sex differences. The present study aimed to examine individual and parental/familial factors associated with sex differences in childhood OW/OB rates in China.
Variables associated with child weight status, beliefs and behaviours, and obesity-related parenting practices were selected to examine their sex differences and association with a sex difference in child OW/OB outcomes using logistic regression analysis.
Cross-sectional data analysis using the 2011 China Health and Nutrition Survey.
Children aged 6–17 years (n 1544) and their parents.
Overall child OW/OB prevalence was 16·8 %. Adolescent boys (AB; 12–17 years) were about twice as likely to be overweight/obese as adolescent girls (AG; 15·5 v. 8·4 %, P<0·05). AB more likely had energy intake exceeding recommendations, self-perceived underweight, underestimated their body weight and were satisfied with their physical activity level than AG. AG more likely practised weight-loss management through diet and self-perceived overweight than AB. Mothers more likely identified AG’s weight accurately but underestimated AB’s weight. Stronger associations with risk of childhood OW/OB were found in boys than girls in dieting to lose weight (OR=6·7 in boys v. 2·6 in girls) and combined maternal and child perception of the child’s overweight (OR=35·4 in boys v. 14·2 in girls).
Large sex differences in childhood obesity may be related to the sex disparities in weight-related beliefs and behaviours among children and their parents in China.
The purpose of this study was to investigate the joint associations of dietary pattern and television viewing with risk factors of CVD among urban adults in China. A community-based cross-sectional study was conducted among urban adults in Nanjing, China. Five dietary patterns were identified based on a FFQ. Television time was obtained from a standard questionnaire and further classified into two categories (≤7, >7 h/week). Multiple logistic regression was used to calculate the OR and 95 % CI for the separate and joint associations of dietary patterns and television viewing with CVD risk factors. Compared with other dietary patterns, participants who followed the healthy traditional pattern had a lower likelihood of abdominal obesity (AO) (OR 0·52; 95 % CI 0·41, 0·67). Participants watching television no more than 7 h/week presented a 19 and 21 % lower likelihood for hypertension (HT) and elevated total cholesterol (ETC) than those with television time >7 h/week. Individuals who had less television time and a healthy dietary pattern had a lower OR for the presence of AO (OR 0·48; 95 % CI 0·36, 0·65), HT (OR 0·71; 95 % CI 0·66, 0·77), ETC (OR 0·72; 95 % CI 0·57, 0·91) and elevated TAG (OR 0·76; 95 % CI 0·61, 0·95), compared with those who followed other dietary patterns and television time >7 h/week. In conclusion, both healthy traditional pattern and less television time are jointly associated with reduced levels of CVD risk factors. It has important public health implications regarding the precision prevention of CVD at population level.
Congenital heart disease (CHD) is one of the most common birth defects. More than 200 susceptibility loci have been identified for CHDs, yet a large part of the genetic risk factors remain unexplained. Monozygotic (MZ) twins are thought to be completely genetically identical; however, discordant phenotypes have been found in MZ twins. Recent studies have demonstrated genetic differences between MZ twins. We aimed to test whether copy number variants (CNVs) and/or genetic mutation differences play a role in the etiology of CHDs by using single nucleotide polymorphism (SNP) genotyping arrays and whole exome sequencing of twin pairs discordant for CHDs. Our goal was to identify mutations present only in the affected twins, which could identify novel candidates for CHD susceptibility loci. We present a comprehensive analysis for the CNVs and genetic mutation results of the selected individuals but detected no consistent differences within the twin pairs. Our study confirms that chromosomal structure or genetic mutation differences do not seem to play a role in the MZ twins discordant for CHD.
The novel visible-light-responsive direct solid-state Z-scheme g-C3N4/BiOI heterojunction has been synthesized successfully by means of a solid phase calcination method and used for the degradation of microcystin-LR (MC-LR). The layered g-C3N4 disperses on the surface of BiOI microspheres. The samples are characterized by FESEM, HRTEM, XRD, FT-IR, UV-vis spectroscopy, XPS, BET, PL, and Mott–Sckottky. The photocatalytic activity and photodegradation mechanism of the as-prepared g-C3N4/BiOI microsphere photocatalysts are conducted under visible light irradiation using MC-LR as the target pollutant. The g-C3N4/BiOI material exhibits superior photocatalytic performance when compared with pure BiOI, the possible reason is the efficient separation of photogenerated carriers at the interface between g-C3N4 and BiOI. The heterostructure is responsible for the improved separation efficiency of photogenerated electron–hole pairs and thus the higher photocatalytic activity. The possible photocatalytic mechanism is proposed based on relative band positions of these two semiconductors.
Previous studies have supported the theory that there is a positive association between ferritin and carotid atherosclerosis in Western people. Diet plays an important role in determining serum ferritin concentration. Asian dietary patterns are different from Western dietary patterns, implying that there may be a difference in the association of ferritin with carotid atherosclerosis between Asian and Western people. However, few studies focus on the association between ferritin and carotid atherosclerosis among Asians. The aim of this study was to investigate how serum ferritin levels are associated with carotid atherosclerosis in an Asian adult population. A cross-sectional assessment was performed in 8302 adults in Tianjin, China. Carotid intima-media thickness (IMT) and plaques were assessed using ultrasonography, and serum ferritin was measured using the protein chip-chemiluminescence method. Multiple logistic regression analysis was used to examine the association between quartiles of serum ferritin concentration and carotid atherosclerosis. In the present study, the overall prevalence of IMT and carotid plaques in participants is 29·2 and 22·7 %, respectively. In women, after adjustments for potentially confounding factors, the OR of IMT and carotid plaques by increasing serum ferritin quartiles were 1·00, 1·39 (95 % CI 0·98–1·99), 1·39 (95 % CI 0·99–1·97), 1·81 (95 % CI 1·30–2·55) (Pfor trend<0·001) and 1·00, 1·24 (95 % CI 0·89–1·73), 1·18 (95 % CI 0·85–1·65), 1·59 (95 % CI 1·15–2·20) (Pfor trend<0·01), respectively. However, no association was found between serum ferritin and carotid atherosclerosis in men. The study demonstrated that increased serum ferritin levels are independently associated with IMT and carotid plaques in Asian women but not in Asian men.
The metadynamic recrystallization (MDRX) behavior of a Nb–V microalloyed nonquenched and tempered steel was investigated by isothermal hot compression tests on Gleeble-1500 thermal-mechanical simulator. Compression tests were performed using double hit schedules at temperatures of 1273–1423 K, strain rates of 0.01–5 s−1, initial grain sizes of 92–149 μm and an inter-pass time of 0.5–10 s. The experimental results show that MDRX softening fraction increases with the increasing of deformation temperature, strain rate, and inter-pass time, while it decreases with the increasing of initial grain size. Based on the experimental results, the MDRX softening fraction kinetic model and recrystallized grain size model of the tested steel was established. Besides, using the above mathematic models, a finite element model was built to simulate the MDRX process of the tested steel. The simulation results show good agreement with the experimental ones, which indicates that finite element method is an effective approach to analyze the MDRX behavior and the established that mathematic models of the tested steel are reliable and accurate.
MnOx–CeO2/t-ZrO2 catalyst was prepared by impregnation of nanotetragonal zirconia. The NO conversion of 5 wt% MnOx–CeO2/t-ZrO2 catalyst was 68.1% at 100 °C while that of 30 wt% MnOx–CeO2/t-ZrO2 catalyst was 97.4%. The x-ray diffraction, Brunner–Emmet–Teller measurements (BET), and H2-TPR showed surface properties of the prepared catalysts were good for selective catalytic reduction reactions. X-ray photoelectron spectroscopy analysis indicated that Mn4+ and Ce4+ oxidation states were predominant on the surface of the catalyst and so was lattice oxygen which was conducive to Lewis acid sites. NH3-TPD test results demonstrated that Lewis acid sites are predominant on the surface of catalyst. The presence of SO2 reduced the catalyst activity. The realized conversion dramatically decreased to 47% from nearly 100% after 8 h. Characterization of fresh and spent catalysts indicated the deterioration of active component and deposition of NH4HSO4 or (NH4)2SO4 contribute to SO2 poisoning.
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 the present study, we evaluated the reproducibility and validity of dietary patterns among Chinese adult populations. A random subsample of 203 participants (aged 31–80 years) from a community-based nutrition and health survey was enrolled. An eighty-seven-item FFQ was administered twice (FFQ1 and FFQ2) 1 year apart; four 3 consecutive day, 24-h dietary recalls (24-HDR, as a reference method) were performed between the administrations of the two FFQ every 3 months. Dietary patterns from three separate dietary sources were derived using factor analysis based on twenty-eight predefined food groups. Comparisons between dietary pattern scores were made by using Pearson’s or intraclass correlation coefficients (ICC), cross-classification analysis, weighted κ statistic and Bland–Altman plots; the four major dietary patterns identified from FFQ1, FFQ2 and 24-HDR were similar. Regarding reproducibility, ICC for z-scores between FFQ1 and FFQ2 were all >0·6 for dietary patterns. The ‘animal and plant protein’ pattern had the highest ICC of 0·870. For validity, the adjusted Pearson’s correlation coefficients for dietary pattern z-scores between two FFQ and the mean of four 3 consecutive day 24-HDR ranged from 0·387 for the ‘Chinese traditional’ pattern to 0·838 for the ‘animal and plant protein’ pattern. More than 75 % of the participants were classified into the same or adjacent quartile, and <5 % were misclassified into opposite quartiles. The weighted κ ranged from 0·259 to 0·680. Bland–Altman plots indicated that no significant deviation was found between two dietary assessment methods. Our findings indicate a good reasonable reproducibility and a reasonable validity of dietary patterns derived by factor analysis in China.
Correlative light and electron microscopy (CLEM) offers a means of guiding the search for the unique or rare events by fluorescence microscopy (FM) and allows electron microscopy (EM) to zoom in on them for subsequent EM examination in three-dimensions (3D) and with nanometer-scale resolution. FM visualizes the localization of specific antigens by using fluorescent tags or proteins in a large field-of-view to study their cellular function, whereas EM provides the high level of resolution for complex structures. And cryo CLEM combines the advantages of maintaining structural preservation in a near-native state throughout the entire imaging process and by avoiding potentially harmful pre-treatments, such as chemical fixation, dehydration and staining with heavy metals. Besides for frozen-hydrated biological samples, CLEM combines the advantages of a close-to-life preservation of biological materials by keeping them embedded in vitreous ice throughout the entire imaging process and the frozen-hydrated condition is very suitable to maintain fluorescent signals. In recent years, many new instruments and software which intended to optimize the workflow and to obtain better experimental results of CLEM have been presented or even commoditized. While, the specimen damage during transfer from FM to EM and the resolution of CLEM were still need to be improved.
Here we set up a High-vacuum Optical Platform to develop CLEM imaging technology (HOPE), which was designed to realize high-vacuum optical ( fluorescent) imaging for cryo-sample on EM cryo-holder (e.g. Gatan 626). A non-integrated high-vacuum cryo-optical stage, which adapted to the EM cryo holder, was fixed on epi-fluorescence microscope (or super-resolution microscope) to obtain fluorescent images. And then the EM cryo holder would be transferred to EM for collection of EM data. This protocol was aimed to minimize the specimen damage during transfer from FM to EM and it was versatile to expend to different types of light microscopy or electron microscopy. Our HOPE had already passed correlative imaging test, and the results showed that it was convenient and effective.
Activated carbon materials are integrated into functionalization of graphene nano-sheets to serve as a high-power lithium cathode. The electrochemical performance shows that the composite displays the highest reversible capacity (c. 170 mAh g-1) comparing with functionalized graphene and activated carbon. Also, approximately 92% of its capacity can be retained after 4,000 cycles at a current of 1 A g-1. Moreover, the composite exhibits an excellent rate performance, a reversible capacity of 90 mAh g-1 even at 6 A g-1, which corresponds to the power density of 15.2 kW kg-1 and energy density of 227 Wh kg-1, respectively. The high performance of this composite can be attributed to the fact that the activated carbon particles not only reduce the graphene sheet stacking thus making it easier for ions to diffuse, but also act as an ion storage buffer against accelerating electron transfer.
Mapping global shipping density, including vessel density and traffic density, is important to reveal the distribution of ships and traffic. The Automatic Identification System (AIS) is an automatic reporting system widely installed on ships initially for collision avoidance by reporting their kinematic and identity information continuously. An algorithm was created to account for errors in the data when ship tracks seem to ‘jump’ large distances, an artefact resulting from the use of duplicate identities. The shipping density maps, including the vessel and traffic density maps, as well as AIS receiving frequency maps, were derived based on around 20 billion distinct records during the period from August 2012 to April 2015. Map outputs were created in three different spatial resolutions: 1° latitude by 1° longitude, 10 minutes latitude by 10 minutes longitude, and 1 minute latitude by 1 minute longitude. The results show that it takes only 56 hours to process these records to derive the density maps, 1·7 hours per month on average, including data retrieval, computation and updating of the database.
Very high cycle bending fatigue behaviors of FV520B steel under fretting wear were studied by the ultrasonic fatigue technique. The specimen system for ultrasonic bending testing was designed and the stress distribution of fatigue specimen was obtained by finite element method. The microstructure of FV520B steel was characterized by means of optical microscope, transmission electron microscope, and energy-dispersive spectroscope. The P–S–N curve was drawn based on fatigue data. The micromorphology characteristics of fretting wear surface and fracture surface for fatigue specimen were observed. The results indicate that the microstructure of FV520B steel is mainly composed of lath martensite, ferrite, and precipitation particles, with some randomly distributed internal inclusions. The P–S–N curve shows that there exists no “conventional fatigue limit” and the fatigue life decreases continuously with the increase of applied stress Smax. Most of fatigue cracks are observed on fractography and initiate from the overlap region of fretting wear zone and stress concentration zone. The fracture failure for tested specimen is ascribed to fretting wear and bending vibration fatigue.
We evaluated the reproducibility and validity of an FFQ used in a Chinese community-based nutrition and health survey. A total of ninety-nine males and 104 females aged 31–80 years completed four three consecutive 24-h dietary recalls (24-HDR, served as a reference method, one three consecutive 24-HDR for each season) and two FFQ (FFQ1 and FFQ2) over a 1-year interval. The reproducibility of the FFQ was estimated with correlation coefficients, misclassification and weighted κ statistic. The validity was evaluated by comparing the data obtained from FFQ2 with the mean 24-HDR (m24-HDR). Compared with the m24-HDR, the FFQ tended to underestimate intake of most nutrients and food groups. For all nutrients and food groups, the Spearman’s and intra-class correlation coefficients between FFQ1 and FFQ2 ranged from 0·66 to 0·88 and from 0·65 to 0·87, respectively. Most correlation coefficients decreased after adjusting for energy. More than 90 % of the subjects were classified into the same or adjacent categories by both FFQ. For all nutrients and food groups, the crude, energy-adjusted and de-attenuated Spearman’s correlation coefficients between FFQ2 and the m24-HDR ranged from 0·21 to 0·69, 0·19 to 0·58 and 0·25 to 0·71, respectively. More than 70 % of the subjects were classified into the same and adjacent categories by both instruments. Both weighted κ statistic and the Bland–Altman plots showed reasonably acceptable agreement between the FFQ2 and the m24-HDR. The FFQ developed for adults in the Nanjing area can be used to reliably and validly measure usual intake of major nutrients and food groups.
In this study, we chose a carnivorous fish, turbot (Scophthalmus maximus L.), to examine its nutrient-sensing and metabolic responses after ingestion of diets with fishmeal (FM), or 45 % of FM replaced by soyabean meal (34·6 % dry diet) balanced with or without essential amino acids (EAA) to match the amino acid profile of FM diet for 30 d. After a 1-month feeding trial, fish growth, feed efficiency and nutrient retention were markedly reduced by soyabean meal-incorporated (SMI) diets. Compared with the FM diet, SMI led to a reduction of postprandial influx of free amino acids, hypoactivated target of rapamycin signalling and a hyperactivated amino acid response pathway after refeeding, a status associated with reduced protein synthesis, impaired postprandial glycolysis and lipogenesis. These differential effects were not ameliorated by matching an EAA profile of soyabean meal to that of the FM diet through dietary amino acid supplementation. Therefore, this study demonstrated that the FM diet and SMI diets led to distinct nutrient-sensing responses, which in turn modulated metabolism and determined the utilisation efficiency of diets. Our results provide a new molecular explanation for the role of nutrient sensing in the inferior performance of aquafeeds in which FM is replaced by soyabean meal.
We propose a motor-driven capsule robot based on a sliding clamper (MCRSC), a device to explore the partially collapsed and winding intestinal tract. The MCRSC is powered by wireless power transmission based on near-field inductive coupling. It comprises a novel locomotion unit, a camera, and a three-dimensional receiving coil, all installed at both ends of the locomotion unit. The novel locomotion unit comprises a linear motion mechanism and a sliding clamper. The former adopts a pair of lead-screw and nut to obtain linear motion, whereas the latter anchors the MCRSC to a specific point of the intestinal tract by expanding its arc-shaped legs. The MCRSC is capable of two-way locomotion, which is activated by alternately executing linear motion and anchoring action. Ex vivo experiments have shown that the MCRSC is able to inspect the colon within a time frame of standard colonoscopy.
Postnatal rapid growth by excess intake of nutrients has been associated with an increased susceptibility to diseases in neonates with intra-uterine growth restricted (IUGR). The aim of the present study was to determine whether postnatal nutritional restriction could improve intestinal development and immune function of neonates with IUGR using piglets as model. A total of twelve pairs of normal-birth weight (NBW) and IUGR piglets (7 d old) were randomly assigned to receive adequate nutrient intake or restricted nutrient intake (RNI) by artificially liquid feeding for a period of 21 d. Blood samples and intestinal tissues were collected at necropsy and were analysed for morphology, digestive enzyme activities, immune cells and expression of innate immunity-related genes. The results indicated that both IUGR and postnatal nutritional restriction delayed the growth rate during the sucking period. Irrespective of nutrient intake, piglets with IUGR had a significantly lower villous height and crypt depth in the ileum than the NBW piglets. Moreover, IUGR decreased alkaline phosphatase activity while enhanced lactase activity in the jejunum and mRNA expressions of Toll-like receptor 9 (TLR-9) and DNA methyltransferase 1 (DNMT1) in the ileum of piglets. Irrespective of body weight, RNI significantly decreased the number and/or percentage of peripheral leucocytes, lymphocytes and monocytes of piglets, whereas the percentage of neutrophils and the ratio of CD4+ to CD8+ were increased. Furthermore, RNI markedly enhanced the mRNA expression of TLR-9 and DNMT1, but decreased the expression of NOD2 and TRAF-6 in the ileum of piglets. In summary, postnatal nutritional restriction led to abnormal cellular and innate immune response, as well as delayed the growth and intestinal development of IUGR piglets.