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To evaluate the effects of dietary calcium (Ca) intake and Ca supplementation during pregnancy on low birth weight (LBW) and small for gestational age (SGA) infants.
A birth cohort study was conducted in 2010–2012 at the Gansu Provincial Maternity & Child Care Hospital in Lanzhou, China.
A birth cohort study.
9595 pregnant women who came to the hospital for delivery at 20 weeks of gestation or more, and who were 18 years of age or older.
Compared to non-users, Ca supplement users had a reduced risk of LBW infants (OR = 0.77, 95% CI: 0.63–0.95) and a reduced risk of nulliparous women giving birth to LBW infants (OR= 0.75, 95% CI: 0.58–0.98) (P<0.05). More specific, both use of Ca supplement before conception and during pregnancy (OR=0.44, 95% CI: 0.19-0.99) and during pregnancy only (OR=0.80, 95%CI: 0.65-0.99) had the main effect of reducing risk of nulliparous women giving birth to LBW infants (P<0.05). There was no association between Ca supplementation and SGA (OR = 0.87, 95% CI: 0.75–1.01) (P>0.05). However, higher dietary Ca intake during pregnancy decreases the risk of both LBW (quartile 2: OR=0.72, 95%CI: 0.55-0.94; quartile 3: OR=0.68, 95%CI: 0.50-0.62) and SGA infants (quartile 2: OR=0.77, 95%CI: 0.63-0.95; quartile 3: OR=0.71, 95%CI: 0.57-0.88, quartile 4: OR=0.71, 95%CI: 0.57-0.88) (P<0.05).
Calcium supplementation and adequate dietary intake of calcium during pregnancy are associated with a decreased risk of LBW infants born to nulliparous women.
Corona Virus Disease 2019 (COVID-19) has presented an unprecedented challenge to the health-care system across the world. The current study aims to identify the determinants of illness severity of COVID-19 based on ordinal responses. A retrospective cohort of COVID-19 patients from four hospitals in three provinces in China was established, and 598 patients were included from 1 January to 8 March 2020, and divided into moderate, severe and critical illness group. Relative variables were retrieved from electronic medical records. The univariate and multivariate ordinal logistic regression models were fitted to identify the independent predictors of illness severity. The cohort included 400 (66.89%) moderate cases, 85 (14.21%) severe and 113 (18.90%) critical cases, of whom 79 died during hospitalisation as of 28 April. Patients in the age group of 70+ years (OR = 3.419, 95% CI: 1.596–7.323), age of 40–69 years (OR = 1.586, 95% CI: 0.824–3.053), hypertension (OR = 3.372, 95% CI: 2.185–5.202), ALT >50 μ/l (OR = 3.304, 95% CI: 2.107–5.180), cTnI >0.04 ng/ml (OR = 7.464, 95% CI: 4.292–12.980), myohaemoglobin>48.8 ng/ml (OR = 2.214, 95% CI: 1.42–3.453) had greater risk of developing worse severity of illness. The interval between illness onset and diagnosis (OR = 1.056, 95% CI: 1.012–1.101) and interval between illness onset and admission (OR = 1.048, 95% CI: 1.009–1.087) were independent significant predictors of illness severity. Patients of critical illness suffered from inferior survival, as compared with patients in the severe group (HR = 14.309, 95% CI: 5.585–36.659) and in the moderate group (HR = 41.021, 95% CI: 17.588–95.678). Our findings highlight that the identified determinants may help to predict the risk of developing more severe illness among COVID-19 patients and contribute to optimising arrangement of health resources.
The current study aimed to evaluate the association of major dietary patterns with anxiety in middle-aged adults in eastern China.
Dietary intake was assessed using a semi-quantitative FFQ. Binary logistic regression analysis was used to estimate OR and 95 % CI for anxiety according to quartiles of each dietary pattern score.
Evidence regarding the relationship between dietary patterns and anxiety in the Chinese population is scarce.
The study participants were 1360 Chinese adults aged 45–59 years, who participated in a health survey at the time of periodic check-up in the city of Linyi, Shandong Province, China.
Four major dietary patterns were identified by factor analysis: traditional Chinese, western, grains–vegetables and high-salt diets. After adjusting for potential confounders, participants in the highest quartile of the western pattern had greater odds for anxiety, compared with those in the lowest quartile (OR 1·35, 95 % CI 1·000, 3·086, P < 0·05). In contrast, participants in the highest quartile of the grains–vegetables pattern had lower odds for anxiety than did those in the lowest quartile (OR 0·78, 95 % CI 0·574, 1·000, P < 0·05). Moreover, no significant associations were observed between the traditional Chinese and high-salt patterns and the risk of anxiety.
Our findings indicate that the western pattern is associated with an increased risk, and the grains–vegetables pattern is associated with a decreased risk of anxiety.
We evaluate the timing and environmental controls on past rock-glacier activity at Øyberget, upper Ottadalen, southern Norway, using in situ 10Be surface-exposure dating on (1) boulders belonging to relict rock-glacier lobes at c. 530 m asl, (2) bedrock and boulder surfaces at the Øyberget summit (c. 1200 m asl), and (3) bedrock at an up-valley site (c. 615 m asl). We find that the rock-glacier lobes became inactive around 11.1 ± 1.2 ka, coeval with the timing of summit deglaciation (11.2 ± 0.7 ka). This is slightly older than previously published Schmidt-hammer surface-exposure ages. The timing does not match known climatic conditions promoting rock-glacier formation in the early Holocene; hence we infer that lobe formation resulted from enhanced debris supply and burial of residual ice during and soon after deglaciation. The results demonstrate that rock glaciers may form over a relatively short period of time (hundreds rather than thousands of years) under non-permafrost conditions and possibly indicate a paraglacial type of process.
Plant cyclophilin (CYP) is related to chloroplast photoprotection, redox and other growth and developmental regulatory processes and responds to stress and improves tolerance to saline–alkali stress. Besides, it exerts peptidyl-prolyl cis/trans isomerase activity to participate in protein synthesis and folding. In this study, Northern blot was used to analyse the CsCYP1A gene (a CYP gene isolated from a Chlorella species) (accession number: KY207381) of tolerant Chlorella vulgaris in soda saline–alkali soil. The result showed that the expression of the CsCYP1A gene was induced by NaHCO3, NaCl and sorbitol. Additionally, Agrobacterium tumefaciens was used to infect the callus of rice (Oryza sativa var. Longjing11) for genetic transformation. Molecular detection confirmed that transgenic seedlings overexpressing CsCYP1A were obtained by hygromycin selection. Treatment with NaCl and NaHCO3 at the five-leaf stage was performed in the seedlings, and the results showed that there were significant differences between the CsCYP1A overexpressed rice lines and non-transgenic (NT) Longjing11 in terms of plant height, fresh weight, chlorophyll content, malondialdehyde content and ascorbate peroxidase activity. The CsCYP1A overexpression rice lines had higher tolerance to NaCl and NaHCO3 than NT. The current findings indicate that CsCYP1A can enhance the tolerance of rice to saline–alkali stress possibly through its involvement in reactive oxygen scavenging pathways.
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.
We aimed to investigate the association between plasma retinol and incident cancer among Chinese hypertensive adults. We conducted a nested case–control study, including 231 patients with incident cancer and 231 matched controls during a median 4·5-year follow-up of the China Stroke Primary Prevention Trial. There was a significant, inverse association between retinol levels and digestive system cancer (per 10 μg/dl increases: OR 0·79; 95 % CI 0·69, 0·91). When compared with participants in the first quartile of retinol (< 52·3 μg/dl), a significantly lower cancer risk was found in participants in quartile 2–4 ( ≥ 52·3 μg/dl: OR 0·31; 95 % CI 0·13, 0·71). However, there was a U-shaped association between retinol levels and non-digestive system cancers where the risk of cancers decreased (although not significantly) with each increment of plasma retinol (per 10 μg/dl increases: OR 0·89; 95 % CI 0·60, 1·31) in participants with retinol < 68·2 μg/dl, and then increased significantly with retinol (per 10 μg/dl increase: OR 1·65; 95 % CI 1·12, 2·44) in participants with retinol ≥ 68·2 μg/dl. In conclusion, there was a significant inverse dose–response association between plasma retinol and the risk of digestive system cancers. However, a U-shaped association was observed between plasma retinol and the risk of non-digestive cancers (with a turning point approximately 68·2 μg/dl).
Existing data on folate status and hepatocellular carcinoma (HCC) prognosis are scarce. We prospectively examined whether serum folate concentrations at diagnosis were associated with liver cancer-specific survival (LCSS) and overall survival (OS) among 982 patients with newly diagnosed, previously untreated HCC, who were enrolled in the Guangdong Liver Cancer Cohort (GLCC) study between September 2013 and February 2017. Serum folate concentrations were measured using chemiluminescent microparticle immunoassay. Cox proportional hazards models were performed to estimate hazard ratios (HR) and 95 % CI by sex-specific quartile of serum folate. Compared with patients in the third quartile of serum folate, patients in the lowest quartile had significantly inferior LCSS (HR = 1·48; 95 % CI 1·05, 2·09) and OS (HR = 1·43; 95 % CI 1·03, 1·99) after adjustment for non-clinical and clinical prognostic factors. The associations were not significantly modified by sex, age at diagnosis, alcohol drinking status and Barcelona Clinic Liver Cancer (BCLC) stage. However, there were statistically significant interactions on both multiplicative and additive scale between serum folate and C-reactive protein (CRP) levels or smoking status and the associations of lower serum folate with worse LCSS and OS were only evident among patients with CRP > 3·0 mg/l or current smokers. An inverse association with LCSS were also observed among patients with liver damage score ≥3. These results suggest that lower serum folate concentrations at diagnosis are independently associated with worse HCC survival, most prominently among patients with systemic inflammation and current smokers. A future trial of folate supplementation seems to be promising in HCC patients with lower folate status.
Paediatric Mycoplasma pneumoniae pneumonia (MPP) is a major cause of community-acquired pneumonia in China. Data on epidemiology of paediatric MPP from China are little known. This study retrospectively collected data from June 2006 to June 2016 in Beijing Children's Hospital, Capital Medical University of North China and aims to explore the epidemiological features of paediatric MPP and severe MPP (SMPP) in North China during the past 10 years. A total of 27 498 paediatric patients with pneumonia were enrolled. Among them, 37.5% of paediatric patients had MPP. In this area, an epidemic took place every 2–3 years at the peak, and the positive rate of MPP increased during these peak years over time. The peak age of MPP was between the ages of 6 and 10 years, accounting for 75.2%, significantly more compared with other age groups (χ2 = 1384.1, P < 0.0001). The epidemics peaked in September, October and November (χ2 = 904.9, P < 0.0001). Additionally, 13.0% of MPP paediatric patients were SMPP, but over time, the rate of SMPP increased, reaching 42.6% in 2016. The mean age of paediatric patients with SMPP (6.7 ± 3.0 years old) was younger than that of patients with non-SMPP (7.4 ± 3.2 years old) (t = 3.60, P = 0.0001). The prevalence of MPP and SMPP is common in China, especially in children from 6 to 10 years old. Paediatric patients with SMPP tend to be younger than those with non-SMPP. MPP outbreaks occur every 2–3 years in North China. September, October and November are the peak months, unlike in South China. Understanding the epidemiological characteristics of paediatric MPP can contribute to timely treatment and diagnosis, and may improve the prognosis of children with SMPP.
The fundamental cause for the statically indeterminate problem in the force analysis of overconstrained parallel mechanisms (PMs) is found to be the presence of the linearly dependent overconstrained wrenches. Based on the fundamental cause, a unified expression of the solution for the magnitudes of the constraint wrenches of both the limb stiffness decoupled and limb stiffness coupled overconstrained PMs is derived. When the weight of each link is considered, depending on whether additional component forces are generated along the axes of the overconstrained wrenches, two different situations should be considered. One situation is that no additional component force is generated along the axes of the overconstrained wrenches under the weight of the links in the corresponding limb. In this case, the added constraint wrenches at the limb’s end can be calculated directly, and used as a part of the generalized external wrench. The other situation is that additional component forces are generated. In this case, the elastic deformations in the axes of the overconstrained wrenches generated by those component forces should be considered, and the deformation compatibility equations between the overconstrained wrenches are reformulated.
The associations between Chinese adolescents’ family (maternal, paternal, and sibling) relationship qualities and their adjustment were examined among 540 Chinese families over a one-year period. Path analysis revealed that father-offspring positivity was associated with lower levels of internalising problems, whereas mother-offspring conflict predicted youths’ depressive symptoms and loneliness. Controlling for parent-offspring relationships, sibling intimacy inversely predicted youths’ internalising and externalising problems, whereas sibling conflict predicted youths’ loneliness. Multigroup comparisons revealed that youth gender moderated the associations between maternal conflict and youths’ depressive symptoms, as well as sibling intimacy and youths’ loneliness. Overall, results highlight the importance of family systems for Chinese youths’ mental health and the need to study sibling relationships in future studies of Chinese families.
In this work, corrosion-resistant fluoridated Ca–Mg–P composite coatings were prepared on magnesium alloys via a hydrothermal assisted sol–gel process. All these coatings derived from Coating Sols with different F− concentrations are composed of fluoridated hydroxyapatite, magnesium hydroxide, and dittmarite. When F− concentration of Coating Sol is 0.03 M, the coating exhibited uniform and dense surface, and its thickness reached 32 μm, thus possessing a high charge transfer resistance of 312 ± 12.69 kΩ cm2 in simulated body fluid (SBF). Immersion test in SBF showed that this coating could quickly induce the formation of the mineralized layer, implying relatively high bioactivity. After 49 days of immersion, the original composite coating and newly formed mineralized layer reached 60 μm in thickness, providing effective long-term protection for magnesium alloys. These attractive results indicate that this fluoridated Ca–Mg–P composite coating is a promising protective coating on biodegradable magnesium and magnesium alloy implants for orthopaedic applications.
A simple multiple-input-multiple-output (MIMO) antenna with quad-band-notched characteristics for ultra-wideband (UWB) system is proposed and tested in the article. Based on two similar radiators, the UWB-MIMO system only occupies 22 mm × 28 mm. By etching an inverted L-like meander slot, two inverted L-shaped slots, and adding a C-shaped stub beside the feeding line, four notched bands are realized (3.25–3.6, 5.05–5.48, 5.6–6, and 7.8–8.4 GHz) to suppress interference from WiMAX, lower WLAN, upper WLAN, and uplink of X-band satellite communication system. With a T-like stub extruding from the ground plane, port isolation is effectively improved. The results show that the antenna covers 3.1–10.6 GHz UWB frequency band except four rejected bands and has high isolation of better than −20 dB over most of the frequency band. Moreover, envelope correlation coefficient and good radiation patterns also prove that the introduced antenna is suitable for UWB applications.
Acknowledging increasing demand of dementia care for patients in China, this paper aims to understand the training needs of dementia care from the perspectives of mental health providers by examining who should be the trainees, what should be the contents of training, and how to deliver the training in China.
Using purposive sampling, data were gathered via four focus group discussions with 40 mental health providers in Beijing, China, in 2011. Data were transcribed by independent investigators and then translated into English. Researchers used content analysis to separately identify themes and codes. Discrepancies were discussed until final agreement achieved.
To improve the quality of dementia care, all participants agreed there is a significant need to train both formal or professional (physicians, nurses, hospital administrators, community workers) and informal caregivers (family, friends, or non-kin hired caregivers). For formal or professional caregivers, suggested training content included clinical knowledge of dementia (i.e. pathogenesis, approaches for preventing dementia deterioration) and clinical practice skills (i.e. diagnostic, treatment, caregiving, counseling, communicating skills). For informal caregivers, basic dementia knowledge and home-based caregiving skills such as safety, restorative, stress management, and communication were identified as key training contents. Multilevel support from the government and community centers were considered crucial factors to delivering the training and educating the public to enhance awareness of dementia.
Culturally, sensitive education and specific trainings for formal and informal dementia caregivers are urgently needed in China. Policy and program implications are discussed.
This study examined how financial strain, worry about having no care-giver and social engagement modify the association between widowhood and depressive symptoms among older adults in China. Using national representative data from older adults in China in 2006, we ran structural equation models and ordinary least square regressions to investigate the mediating and moderating effects of financial strain, worry about having no care-giver and social engagement on the association between widowhood and depressive symptoms. All three variables significantly mediated the association between widowhood and depressive symptoms. Compared to their married counterparts, widowed older adults showed more worry about having no care-giver, increased financial strain and lower social engagement, which were significantly associated with depressive symptoms. Higher level of worry about having no care-giver and lower social engagement significantly exacerbated the adverse effects of widowhood on depressive symptoms in the moderation analyses. Our finding of mediating effects suggests that widowhood is negatively related to psychological wellbeing via financial strain, social engagement and care resources. The results regarding moderating effects suggest that alleviating worry about having no care-giver and increasing social engagement may buffer the deleterious effect of widowhood on psychological wellbeing in later life.
In this work, the reduction mechanism of potassium chromate (K2CrO4) was investigated via in situ high-temperature X-ray diffraction coupled with Fourier transform infrared spectroscopy. During the hydrogen reduction of K2CrO4, the formation of K3CrO4, KCrO2, and KxCrO2 were detected for the first time. The study discovered that K2CrO4 was firstly reduced to K3CrO4 and an amorphous Cr(III) intermediate product at low temperature (400–500 °C). Moreover, the K3CrO4 was the only crystalline material at this stage. As the temperature increased, a stabilized amorphous CrOOH was formed. At a high temperature (550–700 °C), KCrO2 was generated. Interestingly, a portion of KCrO2 was spontaneously decomposed during the hydrogen reduction, accompanying by the formation of K0.7CrO2. Finally, the results clearly illustrated the reduction mechanism of K2CrO4: K2CrO4 → K3CrO4 → amorphous intermediate → KCrO2.
This paper presents a numerical study of vortex formation in the impulsively started viscous flow past an infinite wedge, for wedge angles ranging from
. The Navier–Stokes equations are solved in the vorticity-streamfunction formulation using a time-splitting scheme. The vorticity convection is computed using a semi-Lagrangian method. The vorticity diffusion is computed using an implicit finite difference scheme, after mapping the physical domain conformally onto a rectangle. The results show details of the vorticity evolution and associated streamline and streakline patterns. In particular, a hierarchical formation of recirculating regions corresponding to alternating signs of vorticity is revealed. The appearance times of these vorticity regions of alternate signs, as well as their dependence on the wedge angles, are investigated. The scaling behaviour of the vortex centre trajectory and vorticity is reported, and solutions are compared with those available from laboratory experiments and the inviscid similarity theory.
Many studies have suggested that folate-related one-carbon metabolism-related nutrients may play a role in certain cancer risks, but few studies have assessed their associations with the risk for nasopharyngeal carcinoma (NPC). In this study, we investigated the association between four folate-related one-carbon metabolism-related nutrients (folate, vitamin B6, vitamin B12 and methionine) and NPC risk in Chinese adults. A total of 600 patients newly diagnosed (within 3 months) with NPC were individually matched with 600 hospital-based controls by age, sex and household type (urban v. rural). Folate, vitamin B6, vitamin B12 and methionine intakes were measured using a validated seventy-eight-item FFQ. A higher dietary folate or vitamin B6 intake was associated with a lower NPC risk after adjusting for potential confounders. The adjusted OR of NPC for quartiles 2–4 (v. 1) were 0·66 (95 % CI 0·48, 0·91), 0·52 (95 % CI 0·37, 0·74) and 0·34 (95 % CI 0·23, 0·50) (Ptrend<0·001) for folate and 0·72 (95 % CI 0·52, 1·00), 0·55 (95 % CI 0·39, 0·78) and 0·44 (95 % CI 0·30, 0·63) (Ptrend<0·001) for vitamin B6. No significant association with NPC risk was observed for dietary vitamin B12 or methionine intake. The risk for NPC with dietary folate intake was more evident in the participants who were not exposed to toxic substances than in those who were exposed (Pinteraction=0·014). This study suggests that dietary folate and vitamin B6 may be protective for NPC in a high-risk population.
Immigration disrupts the bonding process in families. Maintaining close relationships with adult children can be an important protective factor for older immigrants' health and wellbeing. Quantitative research explaining such close relationships is rare. This study examined factors associated with close parent–child relationships in a purposive sample of 236 older Chinese immigrants in Los Angeles who provided information regarding 365 children. Two-level regression models were estimated to investigate factors contributing to cohesive parent–child relationships among these older adults. The findings showed that co-residence, a characteristic that distinguishes immigrant families from most non-immigrant families, was associated with lower parent–child relationship quality. Frequent contact was associated with closer relationships. While receiving instrumental and monetary support from children was associated with favourable ratings of relationships with children, providing such support to children was not related to parents' assessment of relationship quality. Parental perceptions of children being respectful was also associated with better relationship quality ratings. Overall, the findings demonstrate how family-related changes in the immigration context shape parent–child relationships in later life. Implications for future research and practice are provided.