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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.
Identifying the relative importance of urban and non-urban land-use types for potential denitrification derived N2O at a regional scale is critical for quantifying the impacts of human activities on nitrous oxide (N2O) emission under changing environments. In this study we used a regional dataset from China including 197 soil samples and six land-use types to evaluate the main predictors (land use, heavy metals, soil pH, soil moisture, substrate availability, functional and broad microbial abundances) of potential denitrification using multivariate and pathway analysis. Our results provide empirical evidence that soils on farms have the greatest potential denitrifying ability (PDA) (10.92±6.08ng N2O-N·g–1 dry soil·min–1) followed by urban soil (6.80±5.35ng N2O-N·g–1 dry soil·min–1). Our models indicate that land use (low vs. high human activity), followed by total nitrogen (TN) and heavy metals (Cu, Zn, Pb, Cd) was the most important driver of PDA. In addition, our path analysis suggests that at least part of the impacts of land use on potential denitrification were mediated via microbial abundance, soil pH and substrates including TN, dissolved organic carbon and nitrate. This study identifies the main predictors of denitrification at a regional scale which is needed to quantify the impact of human activities on ecosystem functionality under changing conditions.
Pilophyllia Ge and Yu, 1974 represents a major group of distinctive amplexoid corals in the Silurian, whose taxonomic relationships, species composition, and evolutionary trends remain contentious. A critical revision of type material and new specimens of several species (and subspecies) assigned to Pilophyllia, including the type species P. involuta Ge and Yu, 1974, provides solutions to some of these problems. Pilophyllia is revised to include only those forms characterized by a distinct peripheral stereozone and amplexoid major septa with club-shaped rhabdacanths set in thick lamellar stereomes. Other species, previously referred to Pilophyllia but having generally short septa with wedge-shaped rhabdacanths, are transferred herein to the new genus Neopilophyllia Wang. Both genera, together with other Silurian amplexoid rugosan genera such as Amplexoides, are referred to the new family Amplexoididae Wang, which is thought to be evolutionarily unrelated to the much younger (Devonian to early Carboniferous) amplexoid rugosan family Amplexidae Chapman, 1893. The first appearance of Neopilophyllia n. gen. in the middle Telychian, much later than that of Pilophyllia in the late Rhuddanian, probably marks a significant stage during the evolution of Silurian amplexoid corals.
The microstructure evolution of high nitrogen austenitic steel wires under various annealing times and drawing temperatures was carefully characterized. Special attention was paid to the widely distributed twins and the nanoprecipitates at twin boundaries (TBs) in high nitrogen stainless steels (HNSSs). The results of microhardness indicated that the traditional Hall–Petch (H–P) equation, which only took the role of grain boundaries into account, was unsuitable. A new H–P equation that connected grain size, twin density, precipitates at TBs, and microhardness in HNSS was established for the first time and showed to be in good agreement with the experimental results. By analyzing the strained regions near TBs, a model describing the precipitation of nano-M23C6 carbides on coherent twin boundaries and incoherent twin boundaries was proposed. In addition, the influence mechanism of the nano-M23C6 at TBs on microhardness was discussed.
To investigate the predictive ability of the previously established global cerebrovascular disease (CeVD) burden scale on long-term clinical outcomes in a longitudinal study of Asian elderly participants across the spectrum of cognitive impairment.
A case-control study was conducted over a 2-year period involving participants with no cognitive impairment, cognitive impairment-no dementia (CIND), and Alzheimer's disease (AD). Annually, cognitive function was assessed with a comprehensive neuropsychological battery and the clinical dementia rating (CDR) scale was used to stage disease severity.
Of 314 participants, 102 had none/very mild CeVD, 31 mild CeVD, 94 moderate CeVD, and 87 severe CeVD at baseline. There was a 1.14 and 1.42 units decline per year on global cognitive z-scores in moderate and severe CeVD groups, respectively, compared to none/very mild CeVD. Moderate-severe CeVD predicted significant functional deterioration at year 2 (HR = 2.0, 95% CI = 1.2–3.4), and conversion to AD (HR = 6.3, 95% CI = 1.7–22.5), independent of medial temporal atrophy.
The global CeVD burden scale predicts poor long-term clinical outcome independent of neurodegenerative markers. Furthermore, CeVD severity affects the rate of cognitive and functional deterioration. Hence, cerebrovascular burden, which is potentially preventable, is a strong prognostic indicator, both at preclinical and clinical stages of AD, independent of neurodegenerative processes.
The pathophysiology of cognitive impairment in patients with the major depressive disorder (MDD) may involve neuroinflammation mediated by cytokines.
The aim of this study was to examine the serum interleukin-6 (IL-6) levels, sustained attention, and their association in patients with MDD.
Thirty patients with MDD and 30 healthy controls were enrolled in this case-control study. Sustained attention was measured using the Rapid Visual Information Processing (RVP) task in the Cambridge Neuropsychological Tests Automated Battery. The serum IL-6 levels of all subjects were assessed by sandwich enzyme-linked immunosorbent assays.
There were significant differences in the log10RVP total hits, log10RVP total misses, and log10RVP mean latency between patients with MDD and healthy controls (F = 6.04, p = 0.017; F = 19.77, p < 0.0001; F = 14.42, p < 0.0001, respectively). The serum levels of Log10IL-6 were significantly higher in patients with MDD than in healthy controls (F = 192.27, p < 0.0001). The log10IL-6 levels were also positively correlated with the log10RVP mean latency in patients with MDD (r = 0.45, p = 0.013). A further stepwise multivariate regression analysis indicated that the log10IL-6 levels were significantly associated with the log10RVP mean latency in patients with MDD (β = 0.31, t = 2.41, p = 0.025).
Our data suggested that increased IL-6 levels were associated with the psychopathology of MDD, and that abnormal IL-6 levels were implicated in the impairment of sustained attention in patients with MDD.
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.
Observational studies and treatment trials investigating nutrition and cognitive function, with a focus on folate and soya and dementia, were reviewed. Data suggested that effects of folic acid based interventions may only be shown before cognitive decline is evident and/or if people are folate deficient. In older people in Indonesia, Hawai'i and China, tofu, which can contain high levels of phytoestrogens, was found to increase dementia risk. This association was not mediated by a vegetarian diet, socioeconomic status, formaldehyde, thyroid function, or loss of teeth. On the other hand, human observational and animal treatment studies suggested that tempe, a fermented soya product containing phytoestrogens and folate, reduced dementia risk and improved memory. High oestrogen levels were found to increase dementia risk in older women. However, in women with adequate serum folate, high oestrogen levels did not confer additional dementia risk and may protect ageing neurons. In conclusion, reviews seem to suggest that folic acid interventions are only effective on cognitive outcomes in people who are folate deficient and do not have cognitive impairment. Frequent consumption of tofu may have detrimental effects on memory and increase dementia risk in older East Asian people, while tempe may reduce these risks. Possibly folate in tempe offsets the potential negative effects of oestrogenic compounds on ageing neurons.
China’s urban population has experienced rapid fertility decline over the past six decades. This drastic change will have a significant impact on China’s demographic, social and economic future. However, the patterns and characteristics of urban China’s fertility decline have not been systematically examined. This study analyses the trends and age patterns of fertility in urban China since the 1950s, and summarizes the major characteristics of reproductive behaviours into four ‘lows’: extremely ‘low’ level of fertility; ‘low’ proportion of two and higher parity births; ‘low’ mean age at birth; and ‘low’ level of childlessness. The paper argues that the highly homogenous reproductive behaviours found in China’s now near 800 million urban population have been in part shaped by the country’s unprecedented government intervention in family planning. The ‘later, longer, fewer’ campaign in the 1970s and the ‘one-child’ policy, in particular, have left clear imprints on China’s reproductive norms and fertility patterns. The government-led family planning programme, however, has not been the only driving force of fertility decline. A wide range of social, economic, political and cultural changes have also affected the transition in family formation, reproductive behaviour and fertility patterns, and this has become increasingly prominent in the past two decades.
Temperate glaciers are more sensitive to climate changes than polar or continental glaciers, and can drive remarkable runoff variation in local water catchments. Here we present recent glacier shrinkage and runoff change for Hailuogou glacier, a typical monsoon temperate glacier on the east slope of Mount Gongga (Minya Konga), China. The surface area of Hailuogou glacier has decreased by 3.5% (0.92 km2) between 1966 (aerial photographs) and 2007 (ASTER images). Flow measurements at a stream gauge about 500 m down-glacier commencing in 1994 display a remarkable increase in annual runoff (mostly during July–September) since 1999. Annual runoff over the same period in a nonglacierized but forested subcatchment (9.17 km2) did not experience significant change. By separating the daily rainfall component from the daily total discharge, monthly catchment water-balance series were calculated for the period 1994–2005, which shows an increasing trend of glacier storage loss. We concluded that air-temperature rise (with a trend of +0.2°C (10 a)−1 between 1988 and 2005, recorded at nearby weather stations) has had an increased effect on glacier mass loss and river runoff change during the past 20 years.
More than 200 molecular clouds were newly found distributed beyond the Outer arm in the extreme outer Galaxy (EOG) region by MWISP. Those MCs roughly following the HI′s distribution well delineate the outermost spiral structure (the Outer Scutum-Centaurus arm) and warp of our Galaxy. Besides, those MCs show different σv-Radius relation and exhibit higher value of αvir than MCs in the inner Galaxy.
Some basic conceptions of relativistic reference systems are given. The conventional solar-system barycentric reference system (B-system) and the conventional geocentric reference system (G-system) are discussed. It is suggested that the harmonic conditions be used in the definition of the B-system and the G-system be defined by the B-system and the coordinate transformation given by eqs (3–2), (3–3) and (3–4).
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.
The concept of reference system, reference frame, coordinate system and celestial sphere in a relativistic framework are given. The problems on the choice of celestial coordinate systems and the definition of the light deflection are discussed. Our suggestions are listed in Sec. 5.
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.
Studies quantifying relationships between floods and diarrheal diseases have mainly been conducted in low-latitude regions. It’s therefore increasingly important to examine these relationships in midlatitude regions, where they may have significant public health implications. This study aimed to examine the association between floods and bacillary dysentery in the city of Dalian, China.
A generalized additive mixed model was applied to examine the association between floods and bacillary dysentery. The relative risk (RR) of flood impact on bacillary dysentery was estimated.
A total of 18,976 cases of bacillary dysentery were reported in Dalian during the study period. Two weeks’ lagged effect was detected from the impact of floods on bacillary dysentery. The RR of flood impact on bacillary dysentery was 1.17 (95% CI: 1.03-1.33).
Floods have significantly increased the risk of bacillary dysentery in Dalian. More studies should focus on the association between floods and infectious diseases in different regions. Our findings have significant implications for managing the negative health impact of floods in the midlatitude region of China. (Disaster Med Public Health Preparedness. 2017;11:190–195)
In this paper, a W-band (80 GHz) sub-harmonic mixer (SHM) IC is designed, fabricated and measured in 130-nm SiGe BiCMOS technology. The presented SHM IC makes use of a common emitter common collector transistor pair structure with a bottom-LO-configuration to decrease the LO power requirement and a tail current source to flatten the conversion gain. On-chip Marchand balun is designed for W-band on-wafer measurements. The SHM IC presented in this paper has exhibited a conversion gain of 3.9 dB at 80 GHz RF signal with an LO power of only −7 dBm at 39.5 GHz. The mixer core consumes only 0.68 mA at a supply voltage of 3.3 V.
Poly(lactic acid) (PLA)/graphene oxide (GO) nanocomposites were prepared by solution mixing. Differential scanning calorimetry results indicated that GO was an effective nucleating agent. The size of spherulites decreased, the density of spherulites increased with increasing GO and the crystallinity of PLA increased from 4.34 to 49.01%. For isothermal crystallization, the crystallization rates of PLA/GO nanocomposites were significantly higher than that of neat PLA, in which t0.5 reduced from 9.0 to 2.8. Spindle-like nanopores (about 100–200 nm) that arranged like spherulites were prepared by low temperature foaming. It was found that the crystallization rate increase and spherulite morphology change were insignificant when the content of GO exceeded 0.5 wt%, because the excessive GO increased the number of nucleation sites while restricting the PLA crystal growth. Thus, the arrangement of nanopores did not mimick the spherulites because of imperfect crystal morphology.
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.