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Sporadic clusters of healthcare-associated coronavirus disease 2019 (COVID-19) occurred despite intense rostered routine surveillance and a highly vaccinated healthcare worker (HCW) population, during a community surge of the severe acute respiratory coronavirus virus 2 (SARS-CoV-2) B.1.617.2 δ (delta) variant. Genomic analysis facilitated timely cluster detection and uncovered additional linkages via HCWs moving between clinical areas and among HCWs sharing a common lunch area, enabling early intervention.
The association of Fe metabolism with obesity in children remains unclear. The present study aimed to assess the status of Fe metabolism parameters, the prevalence of anaemia, Fe deficiency (ID) and Fe-deficiency anaemia (IDA), and the associations of these variables with obesity in Chinese schoolchildren.
A cross-sectional study conducted in 5295 schoolchildren aged 7–11 years in Guangzhou, China, 2014–2015. Full data of anthropometric and Fe metabolic parameters were collected to assess obesity, anaemia, ID and IDA. Logistic regression models were established to determine the possible associations of anaemia, ID and IDA with obesity. Two-tailed P values of <0·05 was considered statistically significant.
Guangzhou City, China.
Schoolchildren aged 7–11 years (n 5295).
In this sample, mean Hb concentration was 128·1 g/l and the prevalence of anaemia, ID and IDA was 6·6, 6·2 and 0·6 %, respectively. Of the participants, 14·0 % were overweight and 8·8 % were obese. Importantly, obesity was associated with lower anaemia risk (adjusted OR = 0·553; 95 % CI 0·316, 0·968) but higher ID risk (adjusted OR = 1·808; 95 % CI 1·146, 2·853) after adjustment for confounders. No significant relationship was found between obesity and IDA.
Our results confirmed that anaemia and ID remain public health concerns among schoolchildren in Guangzhou, while IDA is remarkably less prevalent. Furthermore, obesity was associated with lower anaemia risk, but higher ID risk. More efforts should be made to prevent the onset of ID and obesity in the same individual, thus improving the health and fitness of children.
Iodine intake and excretion vary widely; however, these variations remain a large source of geometric uncertainty. The present study aims to analyse variations in iodine intake and excretion and provide implications for sampling in studies of individuals or populations. Twenty-four healthy women volunteers were recruited for a 12-d sampling period during the 4-week experiment. The duplicate-portion technique was used to measure iodine intake, while 24-h urine was collected to estimate iodine excretion. The mean intra-individual variations in iodine intake, 24-h UIE (24-h urinary iodine excretion) and 24-h UIC (24-h urinary iodine concentration) were 63, 48 and 55 %, respectively, while the inter-individual variations for these parameters were 14, 24 and 32 %, respectively. For 95 % confidence, approximately 500 diet samples or 24-h urine samples should be taken from an individual to estimate their iodine intake or iodine status at a precision range of ±5%. Obtaining a precision range of ±5% in a population would require twenty-five diet samples or 150 24-h urine samples. The intra-individual variations in iodine intake and excretion were higher than the inter-individual variations, which indicates the need for more samples in a study on individual participants.
There is a dearth of data on the iodine balance studies of Chinese population. In the present study, we aimed to explore the appropriate recommended nutrient intake (RNI) of iodine based on healthy Chinese women. A 4-week study was conducted in twenty-five Chinese euthyroid women. Uniform diets with different iodine contents were provided in two different periods, in which non-iodised salt was given in the first 3 weeks, followed by 1 week of iodised salt administration. The total iodine intake from diet, water and air as well as the total iodine excretion through urine, faeces and respiration were monitored and determined. The sweat iodine loss was also considered. Moreover, the regression curve model was established between the 24 h iodine intake and 24 h iodine excretion. The 24 h iodine intake in the two periods was 194·8 (sd 62·9) and 487·1 (sd 177·3) μg/d, respectively. The 24 h iodine excretion was 130·9 (sd 39·5) and 265·4 (sd 71·8) μg/d, respectively. Both 24 h iodine intake and 24 h iodine excretion of the two periods were significantly different (all P<0·05). The iodised salt contributed approximately 62·7 % of the total daily iodine intake. Moreover, 92·3 % (277/300) of samples were in positive balance, while twenty-three cases were in negative balance. Our data show that the estimated average requirement for iodine was 110·5 μg/d. Therefore, the RNI for iodine to non-pregnant, non-lactating Chinese women was 154·7 μg/d.
In this work, differential scanning calorimetry (DSC) was used to characterize and analyze the precipitation/dissolution kinetics of second phase particles during the cooling/reheating process in a vanadium microalloyed steel. The results indicated that three obvious exothermic peaks were detected on the cooling DSC curve. Furthermore, three corresponding endothermic peaks were also detected on the heating DSC curve. Combined with thermodynamic calculation and transmission electron microscopy analysis, these three exothermic peaks along cooling DSC curve were defined as the precipitation reaction of V(CN), the reaction of austenite transformation into ferrite and the precipitation reaction of VC, respectively. Meanwhile, three corresponding reverse reactions for cooling were also defined along the reheating DSC curve. The linear regression result revealed that the precipitation activation energies for V(CN) and VC were identified as 311.2 kJ/mol and 167.6 kJ/mol, respectively. The dissolution activation energies for VC and V(CN) were identified as 255.4 kJ/mol and 592.6 kJ/mol, respectively.
To observe the five-year efficacy of standardised specific subcutaneous immunotherapy for house dust mite allergy in monosensitised and polysensitised children with persistent allergic rhinitis.
From January 2007 to August 2009, 236 children with persistent allergic rhinitis were divided into 2 groups: 1 group received standardised specific subcutaneous immunotherapy using house dust mite extract; the other received pharmacotherapy with intranasal corticosteroids and oral antihistamines. A total of 193 patients (106 in the immunotherapy group and 87 in the pharmacotherapy group) completed treatment. Scores for symptoms, total medication and quality of life were evaluated.
The subcutaneous immunotherapy group demonstrated a significant reduction in visual analogue scale scores, Rhinoconjunctivitis Quality of Life Questionnaire scores and total medication scores (p < 0.05) compared with the pharmacotherapy group. No significant differences in the visual analogue scale and Rhinoconjunctivitis Quality of Life Questionnaire scores were found between the polysensitised and monosensitised subgroups (p > 0.05). No serious adverse events occurred.
Standardised subcutaneous immunotherapy has long-term efficacy for children with persistent allergic rhinitis. Single-allergen subcutaneous immunotherapy was appropriate for allergic rhinitis caused by multiple allergens, including house dust mites, in the paediatric population.
The Luziyuan Pb–Zn skarn deposit, located in the Baoshan–Narong–Dongzhi block metallogenic belt in SW China, is hosted by marble and slate in the upper Cambrian Shahechang Formation. Three skarn zones have been identified from the surface (1495 m above sea level (asl)) to a depth of 1220 m asl: zone 1 consists of chlorite–actinolite–calcite–quartz, zone 2 of rhodonite–actinolite–fluorite–quartz–calcite, and zone 3 contains garnet–rhodonite–actinolite–fluorite–quartz–calcite. The deposit formed in four distinct mineralization stages: an early anhydrous skarn (garnet, rhodonite and bustamite) stage (Stage 1), a hydrous skarn (actinolite and chlorite) stage (Stage 2), an early quartz (coarse barren quartz veins) stage (Stage 3) and a late sulphide-forming (fine sulphide-bearing quartz veins) stage (Stage 4). The Stage 1 skarn-forming fluid temperature was at least 500 °C according to the geothermometer with rhodonite/bustamite trace elements measured by laser ablation – inductively coupled plasma – mass spectrometry (LA-ICP-MS). A decrease in ore fluid temperatures with time is consistent with the decreases in the δ18Ofluid and δDfluid values from Stage 3 to 4. This trend suggests that the ore fluid was mainly derived from magmatic water and mixed with large amounts of meteoric water during mineralization. The δ34S values of Stage 4 chalcopyrite, sphalerite and galena are similar to those of an Ordovician gypsum layer, and together with the high-salinity fluids in Stage 4 indicate the dissolution of evaporites in the Luziyuan region. Overall, the results of this study suggest that the Luziyuan deposit is a distal Pb–Zn skarn deposit that formed in response to multi-stage alteration associated with a combination of magmatic water and meteoric water.
The effects of soluble fiber inclusion in gestation diets with varying fermentation characteristics (fermentation kinetics and short-chain fatty acids (SCFA)-profile) on lactational feed intake of sows and their piglet growth over two parities were investigated using an in vitro–in vivo methodology. After breeding, 90 multiparous Landrace sows were randomized to one of three experimental diets: the control (CON) diet, konjac flour (KF) diet or sugar beet pulp (SBP) diet. All diets had similar levels of net energy, CP, insoluble fiber and NDF, but KF and SBP diets had higher soluble fiber levels than the CON diet. During gestation, the sows were restrictively fed with three different diets, but during lactation, all the sows were similarly fed ad libitum. The three gestation diets were enzymatically hydrolyzed using pepsin and pancreatin, and enzymolyzed residues were used in in vitro fermentation. Gas and SCFA production were monitored during fermentation. After fermentation, enzymolyzed residues of KF or SBP diets resulted in higher final asymptotic gas volume than those of the CON diet. The enzymolyzed residues of KF diet were mainly part of rapidly fermented fractions, whereas those of SBP diet were mainly part of slowly fermented fractions. In addition, the acetic acid, butyric acid and total SCFA concentrations of enzymolyzed residues of KF diet were higher (P<0.01) than the control and SBP diets. In the in vivo studies, on day 90 of gestation, the KF diet sows had higher plasma SCFA concentration (P<0.05) at 4 h after feeding than the CON diet sows. Furthermore, the KF diet sows had lower plasma free fatty acid (FFA) concentration (P<0.01) at 4 h after feeding, and a lower value of homeostasis model assessment (HOMA)-insulin resistance (P<0.05), but a higher value of HOMA-insulin sensitivity (P<0.01). The KF diet sows also consumed more feed during lactation (P<0.01) and weaned significantly heavier pigs (P<0.01) than the CON diet sows. The overall results showed that the high fermentation capacity KF diet contributed to an increased lactational feed intake and improved performance of piglets in the second reproductive cycle.
Carbon nanofibers are prepared via the electrospinning method accompanied by the phase-separation process using polyacrylonitrile as a carbon precursor. Effects of preoxidation and carbonation temperatures on electrochemical performance are studied and optimized in detail. The morphology and porous structure are characterized by scanning electron microscope, transmission electron microscope, and nitrogen adsorption and desorption measurements, respectively; the electrochemical performances are measured by the CHI660E workstation. The results show that the diameter of carbon nanofibers is about 150–200 nm with a uniform and smooth surface. The optimized preoxidation temperature is 280 °C with a carbonation temperature of 700 °C. The highest capacitance is up to 155 F/g, and the symmetric supercapacitor delivers a maximum energy density of 7.78 W h/kg with a power density of 400 W/kg and a maximum power density of 4000 W/kg with an energy density of 2.0 W h/kg. The symmetric supercapacitor also exhibits good cycle stability 91.0% of initial specific capacitance after 5000 cycles.
We tested the hypotheses that supplementation of a diet with elemental Mg increases ruminal dissolved H2 (dH2) in rumen fluid, which in turn alters rumen fermentation and microbial community in goats. In a randomised block design, twenty growing goats were allocated to two treatments fed the same basal diet with 1·45 % Mg(OH)2 or 0·6 % elemental Mg. After 28 d of adaptation, we collected total faeces to measure total tract digestibility, rumen contents to analyse fermentation end products and microbial groups, and measured methane (CH4) emission using respiration chambers. Ruminal Mg2+ concentration was similar in both treatments. Elemental Mg supplementation increased dH2 at 2·5 h post morning feeding (+180 %, P<0·001). Elemental Mg supplementation decreased total volatile fatty acid concentration (−8·6 %, P<0·001), the acetate:propionate ratio (−11·8 %, P<0·03) and fungal copy numbers (−63·6 %, P=0·006), and increased propionate molar percentage (+11·6 %, P<0·001), methanogen copy numbers (+47·9 %, P<0·001), dissolved CH4 (+35·6 %, P<0·001) and CH4 emissions (+11·7 %, P=0·03), compared with Mg(OH)2 supplementation. The bacterial community composition in both treatments was overall similar. Ruminal dH2 was negatively correlated with acetate molar percentage and fungal copy numbers (P<0·05), and positively correlated with propionate molar percentage and methanogen copy numbers (P<0·05). In summary, elemental Mg supplementation increased ruminal dH2 concentration, which inhibited rumen fermentation, enhanced methanogenesis and seemed to shift fermentation pathways from acetate to propionate, and altered microbiota by decreasing fungi and increasing methanogens.
Japanese brome is a winter annual weed commonly found in wheat fields in China. Laboratory and greenhouse experiments were carried out to determine the effect of temperature, light, pH, osmotic stress, salt stress, and burial depth on the germination and emergence of Japanese brome. Germination was greater than 98% under a wide temperature range of 5 to 30 C and onset of germination was shortened as temperature increased. Light was not required for germination to occur and pH values from 5 to 10 had insignificant effect on germination. Germination was reduced by osmotic stress or salt stress and no germination occurred at −1.3 MPa or 360 mM, suggesting that Japanese brome seed was quite tolerant to osmotic potential and salinity. Seedling emergence was greatest (98%) when seeds were placed on the soil surface but decreased with increasing of burial depth. Only 7% of seedlings emerged at a depth of 5 cm. The results of this study have contributed to our understanding of the germination and emergence of Japanese brome and should enhance our ability to develop better control strategies in wheat farming systems of the Huang-Huai-Hai Plain of China.
By using high purity aluminum powders and multi-walled carbon nanotubes (MWCNTs) as raw materials, MWCNTs/Al composites were fabricated with ball milling, followed by cold pressing, vacuum sintering, and hot extrusion. It was found that when the sintering temperature was 863 K, MWCNTs/Al composite sintered for 4 h showed good comprehensive properties, and its tensile strength and elongation reached to 156 MPa and 21%, respectively. The comprehensive mechanical properties of the composites became better with raising sintering temperature when the sintering time was 4 h. When the sintering temperature raised to 923 K, the tensile strength of the composite reached to 167 MPa which is three times more than that of annealed high purity aluminum, mainly due to the higher density and better interface bonding resulted from higher sintering temperature. CNTs' pulling out were observed obviously in the fractured surfaces, and load transfer may be the main strengthening mechanism.
To explore the prevalence and determinants of chronic post-traumatic stress disorder (PTSD) among flood victims.
A cross-sectional survey was carried out in 2014 among individuals who had experienced the 1998 floods and had been diagnosed with PTSD in 1999 in Hunan, China. Cluster sampling was used to select subjects from the areas that had been surveyed in 1999. PTSD was diagnosed according to DSM-IV criteria, social support was measured according to a Social Support Rating Scale, coping style was measured according to a Simplified Coping Style Questionnaire, and personality was measured by use of the revised Eysenck Personality Questionnaire Short Scale for Chinese. Data were collected through face-to-face interviews by use of a structured questionnaire. Multivariate logistic regression analysis was used to reveal the determinants of chronic PTSD.
A total of 123 subjects were interviewed, 17 of whom (14.4%) were diagnosed with chronic PTSD. Chronic PTSD was significantly associated with disaster stressors (odds ratio [OR]: 1.74; 95% confidence interval [CI]: 1.22-2.47), nervousness (OR: 1.09; 95% CI: 1.01-1.17), and social support (OR: 0.85; 95 CI%: 0.74-0.98).
Chronic PTSD in flood victims is significantly associated with disaster stressors, nervousness, and social support. These factors may play important roles in identifying persons at high risk of chronic PTSD. (Disaster Med Public Health Preparedness. 2015;9:504–508)
The transformation of state-owned enterprises (SOEs) into efficient entities has been an important approach in transition economies. However, the transition literature reveals little about how control structure affects firm performance of transformed SOEs. Drawing on agency theory, we distinguish three modes of control in transformed SOEs: state-controlled, dispersedly controlled, and privately controlled modes and argue that actual control after transformation plays a critical role in determining performance. Examining the impact of different control modes in China, we find that the key is who controls the transformed firm. Non-state-controlled (dispersedly controlled and privately controlled) firms are more likely to have enhanced post-transformation performance and reduced agency costs than state-controlled firms.
Considerable controversy exists regarding the associations of dietary patterns with the risk of all-cause, CVD and stroke mortality. Therefore, a meta-analysis was conducted to elucidate the potential associations between dietary patterns and the risk of all-cause, CVD and stroke mortality. The PubMed database was searched for prospective cohort studies on the associations between dietary patterns and the risk of all-cause, CVD and stroke mortality published until February 2014. Random-effects models were used to calculate the summary relative risk estimates (SRRE) based on the highest v. the lowest category of dietary pattern scores. Stratified analyses were conducted based on sex, geographical region, follow-up duration, and adjustment/non-adjustment for energy intake. A total of thirteen prospective cohort studies involving 338 787 participants were included in the meta-analysis. There was evidence of inverse associations between the prudent/healthy dietary pattern and the risk of all-cause (SRRE = 0·76, 95 % CI 0·68, 0·86) and CVD (SRRE = 0·81, 95 % CI 0·75, 0·87) mortality and an absence of association between this dietary pattern and stroke mortality (SRRE = 0·89, 95 % CI 0·77, 1·02). However, no significant associations were observed between the Western/unhealthy dietary pattern and the risk of all-cause (SRRE = 1·07, 95 % CI 0·96, 1·20), CVD (SRRE = 0·99, 95 % CI 0·91, 1·08) and stroke (SRRE = 0·94, 95 % CI 0·81, 1·10) mortality. In conclusion, the findings provide evidence that greater adherence to a prudent/healthy dietary pattern is associated with a lower risk of all-cause and CVD mortality and not significantly associated with stroke mortality and that the Western/unhealthy dietary pattern is not associated with all-cause, CVD and stroke mortality. Further studies are required to confirm these findings.
To explore (i) the prevalence of thyroid dysfunction in populations with adequate and excessive iodine intakes and (ii) the effect of iodine exposure on the prevalence of thyroid dysfunction.
Cross-sectional study was conducted in Hebei in 2010. The population was classified as having adequate or excessive iodine intake according to the iodine concentration in drinking water. Demographic information was collected by questionnaire. Levels of serum thyroid hormones, thyroid autoantibodies and iodine in drinking water and urine were measured.
Villages with adequate or excessive drinking water iodine in Hebei Province, People’s Republic of China.
A total of 854 men and women aged 20–50 years who had lived in the surveyed areas for over 5 years, including 348 from the adequate iodine area (AIA) and 506 from the excessive iodine area (EIA).
Median urinary iodine concentration was 185 μg/l in AIA and 1152 μg/l in EIA. The prevalence of thyroid dysfunction in AIA was 10·3 %, which included 1·1 % with hypothyroidism and 8·1 % with subclinical hypothyroidism; and 20·6 % in EIA, which included 3·6 % with hypothyroidism and 13·6 % with subclinical hypothyroidism. The positive rates of thyroglobulin antibody were 16·1 % in AIA and 11·9 % in EIA; the positive rates of thyroperoxidase antibody were 20·7 % in AIA and 16·4 % in EIA.
Excessive iodine intake may lead to increased prevalence of biochemical thyroid dysfunction, especially biochemical hypothyroidism. This is not related to an increase in prevalence of thyroid antibodies. Women are more susceptible to iodine excess.
Schizophrenia (SCZ) and bipolar disorder (BD) are common psychotic disorders, which show some overlaps in genetic aetiology. Researchers have conducted a number of studies to investigate the relationship between SCZ and the 1354C/T genetic polymorphism of 5-hydroxytryptamine receptor 2A (HTR2A–1354C/T), as well as the associations between BD and the HTR2A–1354C/T polymorphism. However, the results were conflicting. To provide a more robust estimate about the effects of the HTR2A–1354C/T polymorphism on the risk of these two psychotic disorders, we performed this meta-analysis.
We used the pooled odds ratios (ORs) with 95% confidence intervals (95% CIs) to investigate the relationships between SCZ and the 1354C/T polymorphism of HTR2A, as well as the associations between BD and HTR2A–1354C/T. Publication bias was tested by Begg's test and inverted funnel plot, and heterogeneity was checked by Cochran's Q statistic and the inconsistency index (I2).
Eight studies were concerned with SCZ, analysing a cumulative total of 2953 cases and 3153 controls; six papers studied BD, using a total of 923 cases and 928 controls. There was no significant association found between HTR2A–1354C/T and SCZ in the overall population (T allele vs. C allele, OR = 1.035, 95% CI 0.912–1.175, p = 0.596) or in the subgroups Caucasian population and Asian population. Moreover, there was no significant association between the HTR2A–1354C/T polymorphism and BD in the overall population (T allele vs. C allele, OR = 1.038, 95% CI = 0.607–1.772, p = 0.892).
On the basis of these results, the HTR2A–1354C/T polymorphism is unlikely to be a risk factor for SCZ and BD.
A biomimetic underwater vehicle, which is propelled by two undulating long-fins, is introduced in this paper. The undulating or oscillating movements of symmetrical long-fins cause the complex locomotion of biomimetic underwater vehicle. For convenience, three motion modes are proposed and considered firstly. Then an inertial unit is installed for collection of accelerations and angular velocity. The underwater vehicle's MIMO model is reduced into a SISO model by some simplifications. A sine wave function deduced from the long-fin's time-varying membrane is proposed and used as the input of the biomimetic underwater vehicle ARMA model, and velocity or angular velocity is considered as the model output. The algorithms based on recursive weighted least squares are applied for model parameter identification. Experiments carried out with a long-fin propelled underwater vehicle. The experimental results show that the proposed methods can build valid locomotion models for three motion modes efficiently.