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The mumps resurgence has frequently been reported around the world in recent years, especially in many counties mumps vaccines have been widely used. This study aimed to describe the spatial epidemiological characteristics of mumps in Jiangsu, and provide a scientific basis for the implementation and adjustment of strategies to prevent and control mumps. The epidemiological characteristics were described with ratio or proportion. Spatial autocorrelation, Tango's flexible spatial scan statistics, and Kulldorff's elliptic spatiotemporal scan statistics were applied to identify the spatial autocorrelation, detect hot and cold spots of mumps incidence, and aggregation areas. A total of 172 775 cases were reported from 2004 to 2020 in Jiangsu. The general trend of mumps incidence is declining with a bimodal seasonal distribution identified mainly in summer and winter, respectively. Children aged 5–10 years old are the main risk group. A migration trend of hot spots from southeast to northwest over time was found. Similar high-risk aggregations were detected in the northwestern parts through spatial-temporal analysis with the most likely cluster time frame around 2019. Local medical and health administrations should formulate and implement targeted health care policies and allocate health resources more appropriately corresponding to the epidemiological characteristics of mumps.
This survey examined and compared the disaster perception and preparedness of 2421 residents with and without chronic disease in Shenzhen, China.
The participants were recruited and were asked to complete a survey in 2018.
Three types of disasters considered most likely to happen in Shenzhen were: typhoons (73.5% vs 74.9%), major transport accidents (61.5% vs 64.7%), and major fires (60.8% vs 63.0%). Only 5.9% and 5% of them, respectively, considered infectious diseases pandemics to be likely. There were significant differences between those with and without chronic disease in disaster preparedness, only a small percentage could be considered to have prepared for disaster (20.7% vs 14.5%). Logistic regression analyses showed that those aged 65 or older (odds ratio [OR] = 2.76), who had attained a Master’s degree or higher (OR = 2.0), and with chronic disease (OR = 1.38) were more prepared for disasters.
Although participants with chronic disease were better prepared than those without, overall, Shenzhen residents were inadequately prepared for disasters and in need of public education.
Nutritional Risk Screening index is a standard tool to assess nutritional risk, but epidemiological data are scarce on controlling nutritional status (CONUT) as a prognostic marker in acute haemorrhagic stroke (AHS). We aimed to explore whether the CONUT may predict a 3-month functional outcome in AHS. In total, 349 Chinese patients with incident AHS were consecutively recruited, and their malnutrition risks were determined using a high CONUT score of ≥ 2. The cohort patients were divided into high-CONUT (≥ 2) and low-CONUT (< 2) groups, and primary outcomes were a poor functional prognosis defined as the modified Rankin Scale (mRS) score of ≥ 3 at post-discharge for 3 months. Odds ratios (OR) with 95 % confidence intervals (CI) for the poor functional prognosis at post-discharge were estimated by using a logistic analysis with additional adjustments for unbalanced variables between the high-CONUT and low-CONUT groups. A total of 328 patients (60·38 ± 12·83 years; 66·77 % male) completed the mRS assessment at post-discharge for 3 months, with 172 patients at malnutrition risk at admission and 104 patients with a poor prognosis. The levels of total cholesterol and total lymphocyte counts were significantly lower in high-CONUT patients than low-CONUT patients (P = 0·012 and < 0·001, respectively). At 3-month post discharge, there was a greater risk for the poor outcome in the high-CONUT compared with the low-CONUT patients at admission (OR: 2·32, 95 % CI: 1·28, 4·17). High-CONUT scores independently predict a 3-month poor prognosis in AHS, which helps to identify those who need additional nutritional managements.
Anaemia is a global public health problem affecting women worldwide, and reproductive-age women are at increased risk. We conducted a population-based cross-sectional study analysing the prevalence of overall anaemia and anaemia according to severity in Chinese pre-pregnant women to update current knowledge on anaemia epidemiology. Based on the National Free Preconception Check-up Projects supported by the Chinese government, 5 679 782 women participating in this project in 2017 were included in the present study. The cyanmethemoglobin method was applied to assess Hb concentrations. Univariate and multivariate logistic regressions were applied for associated factors. The prevalence of anaemia among Chinese pre-pregnant women was 21·64 % (mild: 14·10 %, moderate: 7·17 % and severe : 0·37 %). The prevalence of overall and severe anaemia was the highest in Tibet and the lowest in Beijing among thirty-one provinces. Women’s age, region, ethnic origin, educational level, occupation and pregnancy history were all correlated with anaemia. Women with B blood type (adjusted OR (aOR) = 0·89), higher BMI (overweight: aOR = 0·84; obesity: aOR = 0·70) and alcohol consumption (aOR = 0·69) were less likely to have anaemia, while those with rhesus negative blood type (aOR = 1·10), history of anaemia (aOR = 2·60), older age at menarche (aOR = 1·19), heavy menstrual blood loss (aOR = 1·39), longer menstrual period (aOR = 1·09) and shorter menstrual cycle (aOR = 1·08) were more likely to suffer from anaemia. Meat or egg eaters were not significantly associated with severe anaemia. Anaemia is of moderate public health significance among Chinese pre-pregnant women. Interventions should be considered to prevent anaemia to the greatest extent possible to avoid potential harm in this population.
The past 20 years have seen major public health emergencies and natural disasters, including the Severe Acute Respiratory Syndrome outbreak caused by the SARS-associated coronavirus (SARS-CoV) in 2003; the Wenchuan earthquake in 2008; and the novel coronavirus pandemic (COVID-19) of 2019, which caused mass casualties, infections, and panic. These also resulted in complex demands for medical resources and information, and a shortage of human resources for emergency responses. To address the shortage of human resources required for these emergency responses, Chinese dental professionals made useful contributions. From this work, deficiencies in emergency response training and opportunities for the expansion of rescue capabilities were identified, and relevant recommendations made.
Human milk fat is specially tailored to supply the developing infant with adequate and balanced nutrients. The present study aimed to quantify the composition of fatty acids, tocopherols and carotenoids in human milk, with special emphasis on the lactational changes. Colostrum, transitional and mature milk samples were collected longitudinally from the same forty-two healthy, well-nourished Chinese mothers. Fatty acids were quantified by GC with carotenoids (carotenes and xanthophylls) and tocopherols (α-, γ-tocopherol) determined by HPLC. Total fatty acid (TFA) content increased from 15·09 g/l in colostrum to 32·57 g/l in mature milk with the percentages of DHA and arachidonic acid (ARA) decreased. The ratio of n-6:n-3 PUFA and ARA:DHA remained constant during lactation at about 11:1 and 1·3:1, respectively. Both α-tocopherol and γ-tocopherol decreased over lactation with the ratio of α-:γ-tocopherol declined significantly from 7·21:1 to 4·21:1 (P < 0·001). Carotenoids all dropped from colostrum to mature milk as the less polar carotenes dropped by 88·67 %, while xanthophylls only dropped by 35·92 %. Lutein was predominated in both transitional and mature milk carotenoids (51·64–52·49 %), while colostrum carotenoids were mainly composed of lycopene (32·83 %) and β-carotene (30·78 %). The concentrations of tocopherols and xanthophylls but not carotenes were positively associated with TFA content in milk. These results suggested that colostrum and mature milk contained divergent lipid profiles and selective transfer mechanisms related to polarity might be involved. The present outcomes provide new insights for future breast-feeding studies, which also add in scientific evidences for the design of both initial and follow-on infant formulas.
The aim of the present study was to explore the influence of tea consumption on diabetes mellitus in the Chinese population. This multi-centre, cross-sectional study was conducted in eight sites from south, east, north, west and middle regions in China by enrolling 12 017 subjects aged 20–70 years. Socio-demographic and general information was collected by a standardised questionnaire. A standard procedure was used to measure anthropometric characteristics and to obtain blood samples. The diagnosis of diabetes was determined using a standard 75-g oral glucose tolerance test. In the final analysis, 10 825 participants were included and multiple logistic models and interaction effect analysis were applied for assessing the association between tea drinking with diabetes. Compared with non-tea drinkers, the multivariable-adjusted OR for newly diagnosed diabetes were 0·80 (95 % CI 0·67, 0·97), 0·88 (95 % CI 0·71, 1·09) and 0·86 (95 % CI 0·67, 1·11) for daily tea drinkers, occasional tea drinkers and seldom tea drinkers, respectively. Furthermore, drinking tea daily was related to decreased risk of diabetes in females by 32 %, elderly (>45 years) by 24 % and obese (BMI > 30 kg/m2) by 34 %. Moreover, drinking dark tea was associated with reduced risk of diabetes by 45 % (OR 0·55; 95 % CI 0·42, 0·72; P < 0·01). The results imply that drinking tea daily was negatively related to risk of diabetes in female, elderly and obese people. In addition, drinking dark tea was associated with decreased risk of type 2 diabetes mellitus.
The aim of this meta-analysis was to provide a comprehensive overview of human immunodeficiency virus (HIV)-1 subtypes and to investigate temporal and geographical trends of the HIV-1 epidemic among men who have sex with men (MSM) in China. Chinese and English articles published between January 2007 and December 2017 were systematically searched. Pooled HIV-1 prevalence was calculated, and its stability was analysed using sensitivity analysis. Subgroups were based on study time period, sampling area and prevalence. Publication bias was measured using Funnel plot and Egger's test. A total of 68 independent studies that included HIV-1 molecular investigations were eligible for meta-analysis. Circulating recombinant form (CRF) 01_AE (57.36%, 95% confidence interval (CI) 53.76–60.92) was confirmed as the most prevalent HIV-1 subtype among MSM in China. Subgroup analysis for time period found that CRF01_AE steadily increased prior to 2012 but decreased during 2012–2016. Further whereas CRF07_BC increased over time, B/B′ decreased over time. CRF55_01B has increased in recent years, with higher pooled estimated rate in Guangdong (12.22%, 95% CI 10.34–13.17) and Fujian (8.65%, 95% CI 4.98–13.17) provinces. The distribution of HIV-1 subtypes among MSM in China has changed across different regions and periods. HIV-1 strains in MSM are becoming more complex. Long-term molecular monitoring in this population remains necessary for HIV-1 epidemic control and prevention.
This study quantified the fatty acid profile with emphasis on the stereo-specifically numbered (sn) 2 positional distribution in TAG and the composition of main phospholipids at different lactation stages. Colostrum milk (n 70), transitional milk (n 96) and mature milk (n 82) were obtained longitudinally from healthy lactating women in Shanghai. During lactation, total fatty acid content increased, with SFA dominating in fatty acid profile. A high ratio of n-6:n-3 PUFA was observed as 11:1 over lactation due to the abundance of linoleic acid in Chinese human milk. As the main SFA, palmitic acid showed absolute sn-2 selectivity, while oleic acid, linoleic acid and α-linolenic acid, the main unsaturated fatty acids, were primarily esterified at the sn-1 and sn-3 positions. Nervonic acid and C22 PUFA including DHA were more enriched in colostrum with an sn-2 positional preference. A total of three dominant phospholipids (phosphatidylethanolamine (PE), phosphatidylcholine (PC) and sphingomyelin (SM)) were analysed in the collected samples, and each showed a decline in amount over lactation. PC was the dominant compound followed by SM and PE. With prolonged breast-feeding time, percentage of PE in total phospholipids remained constant, but PC decreased, and SM increased. Results from this study indicated a lipid profile different from Western reports and may aid the development of future infant formula more suitable for Chinese babies.
Historically, alloy development with better radiation performance has been focused on traditional alloys with one or two principal element(s) and minor alloying elements, where enhanced radiation resistance depends on microstructural or nanoscale features to mitigate displacement damage. In sharp contrast to traditional alloys, recent advances of single-phase concentrated solid solution alloys (SP-CSAs) have opened up new frontiers in materials research. In these alloys, a random arrangement of multiple elemental species on a crystalline lattice results in disordered local chemical environments and unique site-to-site lattice distortions. Based on closely integrated computational and experimental studies using a novel set of SP-CSAs in a face-centered cubic structure, we have explicitly demonstrated that increasing chemical disorder can lead to a substantial reduction in electron mean free paths, as well as electrical and thermal conductivity, which results in slower heat dissipation in SP-CSAs. The chemical disorder also has a significant impact on defect evolution under ion irradiation. Considerable improvement in radiation resistance is observed with increasing chemical disorder at electronic and atomic levels. The insights into defect dynamics may provide a basis for understanding elemental effects on evolution of radiation damage in irradiated materials and may inspire new design principles of radiation-tolerant structural alloys for advanced energy systems.
Two novel series of cathode materials LiFe1−xMxPO4/C (x ≈ 0.0040; M = Mn, Fe, Co, Ni, Cu, and Zn) composites based on metal phthalocyanines (MPc) and metal tetrasulfophthalocyanines (MPcTs) to modify lithium iron phosphate (LiFePO4) for lithium-ion batteries (LIBs) are in situ prepared by solvothermal and calcination techniques. Structures and morphologies of all the composites are characterized by normal methods. To evaluate the electrochemical performance of the composites, the charge/discharge capabilities, rate performance, cycling stabilities, cyclic voltammetry profiles, and electrochemical impedance spectroscopy plots of the LIBs using them as cathode materials are measured carefully. The results indicate that most of the composites deliver highly improved initial discharge capacity and show remarkable reversibility and cycling stabilities. Especially, composites using MPcTs as additives are more efficient for the improvement of specific capacity, rate capability, reversibility, and cycling stability.
A novel series of binuclear transition metal phthalocyanines M2Pc2HnC (M = Mn(II), Fe(II), Co(II), Ni(II), and Cu(II)) were developed for highly efficient electrocatalysts to lithium/thionyl chloride (Li/SOCl2) battery. The capacity of the battery can increase approximately by 40–65% when the binuclear compounds are present in the electrolyte of the battery. To investigate the effect of the binuclear metal phthalocyanines on Li/SOCl2 battery further, this work studied the electrocatalytic reaction of the binuclear compounds to the battery by electrochemical methods (cyclic voltammetry) and other characterization means. The results demonstrate that the order of the electrocatalytic activity of the binuclear compounds with diverse center metal ions is: Fe(II) > Co(II) > Mn(II) > Ni(II) > Cu(II).
Background: Single-volume proton magnetic resonance spectroscopy (1H MRS) has considerable diagnostic potential for Alzheimer's disease (AD). This study investigated 1H MRS in specific regions of the brain, the posterior cingulate gyri (PCG) and the hippocampus, in patients with AD, amnestic mild cognitive impairment (aMCI), and in normal control subjects.
Methods:1H MRS analysis was carried out on 47 patients with AD, 32 patients with aMCI and 56 normal control subjects (NC group). Volumes of the PCG and hippocampus were assessed, and the metabolic signals of N-acetylaspartate (NAA), choline compounds (Cho), myo-inositol (mI), and creatine (Cr) were quantified.
Results: In the PCG, differences between the test groups were found in NAA/Cr, Cho/Cr, mI/Cr and NAA/mI ratios. Group differences were also found in mI/Cr and NAA/mI ratios in the left hippocampus, and in mI/Cr and NAA/mI ratios in the right hippocampus. NAA/Cr ratios increased in the PCG between AD and aMCI patients, and between aMCI and NC patients. Conversely, mI/Cr ratios in the PCG and left hippocampus decreased across AD, aMCI, and NC subjects. In discriminate and ROC (Receiver Operating Characteristic) analyses, a NAA/Cr ratio of ≤ 1.50 in the PCG indicated optimal potential for discriminating between aMCI patients and normal control subjects. Discriminating potential was also found to be high for a NAA/mI ratio in the PCG of ≤ 2.72. Despite significant differences between NC and aMCI patients in the mI/Cr ratio in the PCG and in the NAA/mI ratio in the left hippocampus, their sensitivity and specificity were all lower than 75%.
Conclusion: Proton MRS of the PCG using the NAA/Cr ratio as a metabolic marker indicates considerable potential for distinguishing between aMCI and NC subjects.
Collision between molecular clouds is considered an efficient mechanism to trigger cloud collapse to form stars. Various observations show that the process is taking place in the universe (Vallee 1995; Wang et al. 2004).
The two-dimensional (2D) Ga-nitride/air photonic quasi-crystals (PQC) were successfully fabricated by the technique of focused Ga ion beam (FIB) milling on GaN based epitaxial wafers. The effects of the PQC on the current injected edge emitting GaN-based light emitters were investigated. The quasi-crystal structures studied in this work are based on square-triangular tiling with 8-fold or 12-fold symmetry. The air hole diameter in the different PQC patterns was varied from 95nm up to 1200nm, the filling factor of air hole was in the range of 10% to 50% and the depth of the hole was 90nm to 370nm, respectively. Among these, the nearest center-to-center distance of the holes and/or the lattice constant was reached to be 170nm. The photonic quasi-crystals on the GaN-based light emitters demonstrated a two to three factor of magnitude enhancement of surface extractive emission. The blocking of the propagation of planar-guided modes by the photonic quasi-crystals was observed. By comparison of symmetry effect among the triangular lattice PC and PQCs, it was found that the GaN-based photonic quasi-crystal (PQC) with 12-fold symmetry provided a much favorable enhancement of the extractive light emission over that of triangle lattice PC and 8-fold symmetric PQC as well.
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