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Lower-crust-derived adakitic rocks in the Gangdese belt provide important constraints on the timing of Tibetan crustal thickening and on the relative contributions of magmatic and tectonic processes. Here we present geochronological and geochemical data for the Wangdui porphyritic monzogranites in the western Gangdese belt. Zircon U–Pb dating yields emplacement ages of 46–44 Ma. All samples have high Sr (321–599 ppm), low Yb (0.76–1.33 ppm) and Y (10.6–18.3 ppm) contents, with high La/Yb (51.1–72.3) and Sr/Y (21.0–51.4) ratios, indicating adakitic affinities. The low MgO (0.97–1.76 wt %), Cr (7.49–53.6 ppm) and Ni (4.75–29.1 ppm) contents, as well as high 87Sr/86Sr(i) (0.7143–0.7145), low ϵNd(t) (−10.4 to −9.8) and zircon ϵHf(t) (−17.7 to 0.4) values, suggest that the Wangdui pluton most likely originated from partial melting of the thickened ancient lower crust. In combination with previously published data, despite the east–west-trending heterogeneity of crustal composition in the Gangdese belt, the La/Yb ratios of magmatic rocks reveal that both western and eastern segments experienced remarkable crustal thickening in the Eocene. However, in contrast to the thickened juvenile lower crust in the eastern segment formed by the underplating of mantle-derived magmas, tectonic shortening plays a more crucial role in thickening of the ancient basement in western Gangdese. In fact, such Eocene-thickened ancient lower-crust-derived adakitic rocks are widely distributed in the central Himalayan–Tibetan orogen. This, together with the extensive development of fold–thrust belts, suggests that tectonic shortening might be the main mechanism accounting for the crustal thickening associated with the India–Asia collision.
Mounting evidence suggests that the first few months of life are critical for the development of obesity. The relationships between the timing of solid food introduction and the risk of childhood obesity have been examined previously; however, evidence for the association of timing of infant formula introduction remains scarce. This study aimed to examine whether the timing of infant formula introduction is associated with growth z-scores and overweight at ages 1 and 3 years. This study included 5733 full-term (≥ 37 gestational weeks) and normal birth weight (≥ 2500 and < 4000 g) children in the Born in Guangzhou Cohort Study, a prospective cohort study with data collected at 6 weeks, 6, 12 and 36 months. Compared with infant formula introduction at 0–3 months, introduction at 4–6 months was associated with the lower BMI, weight-for-age and weight-for-length z-scores at 1 and 3 years old. Also, introduction at 4–6 months was associated with the lower odds of at-risk of overweight at age 1 (adjusted OR 0·72, 95 % CI 0·55, 0·94) and 3 years (adjusted OR 0·50, 95 % CI 0·30, 0·85). Introduction at 4–6 months also decreased the odds of overweight at age 1 year (adjusted OR 0·42, 95 % CI 0·21, 0·84) but not at age 3 years. Based on our findings, compared with introduction within the first 3 months, introduction at 4–6 months has a reduction on later high BMI risk and at-risk of overweight. However, these results need to be replicated in other well-designed studies before more firm recommendations can be made.
Evidence of couples’ BMI and its influence on birth weight is limited and contradictory. Therefore, this study aims to assess the association between couple’s preconception BMI and the risk of small for gestational age (SGA)/large for gestational age (LGA) infant, among over 4·7 million couples in a retrospective cohort study based on the National Free Pre-pregnancy Checkups Project (NFPCP) between December 1, 2013 and November 30, 2016 in China. Among the live births, 256,718 (5·44%) SGA events and 506,495 (10·73%) LGA events were documented, respectively. After adjusting for confounders, underweight men had significantly higher risk [OR 1·17 95%CI (1·15-1·19)] of SGA infants compared with men with normal BMI, while a significant and increased risk of LGA infants was obtained for overweight and obese men [OR 1·08 (95% CI: 1·06-1·09); OR 1·19 (95%CI 1·17-1·20)] respectively. The restricted cubic spline (RCS) result revealed a non-linearly decreasing dose-response relationship of paternal BMI (less than 22·64) with SGA. Meanwhile, a non-linearly increasing dose-response relationship of paternal BMI (more than 22·92) with LGA infants was observed. Moreover, similar results about the association between maternal preconception BMI and SGA/LGA infants were obtained. Abnormal preconception BMIs in either women or men were associated with increased risk of SGA/LGA infants, respectively. Overall, couple’s abnormal weight before pregnancy may be an important preventable risk factor for SGA/LGA infants.
Giardia duodenalis is a common zoonotic intestinal pathogen. It has been increasingly reported in humans and animals; however, genotyping information for G. duodenalis in captive animals is still limited. This study was conducted to assess the prevalence and multilocus genotyping of G. duodenalis in captive animals in zoological gardens in Shanghai, China. A total of 678 fresh fecal samples were randomly collected from captive animals including non-human primates (NHPs) (n = 190), herbivores (n = 190), carnivores (n = 151), birds (n = 138) and reptiles (n = 9) in a zoo and were examined for the presence of G. duodenalis using nested polymerase chain reaction (nested PCR). All G. duodenalis positive samples were assayed with PCR followed by sequencing at β-giardin (bg), glutamate dehydrogenase (gdh) and triose phosphate isomerase (tpi) genes. In this study, 42 specimens (6.2%) were tested G. duodenalis-positive of the 678 fecal samples examined based on a single locus. A total of 30 (4.4%), 30 (4.4%) and 22 (3.2%) specimens were successfully amplified and sequenced at gdh, tpi and bg loci, respectively. Assemblages A and B were identified with assemblage B dominating in NHPs. Sequence analysis demonstrated that one, two and five new isolates were identified at bg, gdh and tpi loci. DNA sequences and new assemblage-subtypes of zoonotic G. duodenalis assemblages A and B were identified in the current study. Our data indicate the occurrence and molecular diversity of G. duodenalis and the potential zoonotic transmission in captive animals in China.
On the basis of air heater characteristics, a new computational model was developed in this paper, which was aimed at investigating acoustics and instabilities in air heaters. This model included the effects of mean flow, viscosity, entropy waves, non-linear acoustics and realistic boundary conditions. In addition, it was practical for air heaters with hundreds of injectors, complex configurations and geometries. Analytical solutions of acoustics in a closed rectangular cavity were used to verify and validate the computational model. It was shown that the predicted critical parameters of air heater agreed well with the experimental data or design values. This model predicted the self-excited spinning tangential modes without any preliminary assumptions about them. Traditional combustion response function assumes that combustion mainly takes place in a so-called rapid combustion zone, and this zone is usually modelled as a disc in the combustor near the injection head. However, in practice, the flame has a spatial distribution. This paper described the effect of flame spatial distribution on predictions of oscillation frequency and mode. It was found that frequency and mode shape of oscillations closely depended on the length of the heat release zone. Comparison of different heat release zones indicated that the increment of heat release length exhibited an increased tendency toward lower-order longitudinal modes, when the heat release zone was located near the faceplate where it was the pressure antinode of the longitudinal mode. Modulation of heat release length might cause bifurcations between standing and turning modes. A noticeable tendency was toward higher-order standing tangential mode with increasing heat release length. Finally, theoretical analysis of the modal behaviour, i.e. standing or spinning waves, was performed.
ABSTRACT IMPACT: Our study will integrate state-of-the-art methods in pathogen genomics, epidemiology, and geospatial analysis to identify both host- and pathogen-factors driving the MDR-TB transmission and the study outcome can inform the design of targeted interventions OBJECTIVES/GOALS: The emergence of multidrug-resistant tuberculosis (MDR-TB) poses serious challenges for the global eradication of tuberculosis. Recent research has shown that transmission is now the dominant driver of MDR-TB. However, our limited understanding of where and among whom MDR-TB is transmitted hampers efforts to control person-to-person spread. METHODS/STUDY POPULATION: We used several analytic approaches to characterize the dynamics of MDR-TB transmission in Shanghai, China. We identified all culture-confirmed MDR cases between 2009-2016 in the city and 1) estimated individual-level risk factors for MDR disease; 2) mapped the TB cases by their home addresses and used a Bayesian spatial disease mapping method to identify regions with an elevated risk of MDR-TB; and 3) we sequenced all MDR isolates to understand whether transmission explained variance in risk that was not attributable to the distribution of individual or location-specific risk variates. RESULTS/ANTICIPATED RESULTS: There were 1034 MDR-TB cases among 16,315 culture-confirmed TB cases during the study period. Bayesian disease mapping identified spatial heterogeneity of MDR-TB and determined four hotspots with an elevated risk of MDR-TB, none of which were fully explained by individual or regional-covariates (Figure 1). Sequencing revealed that more than 40% of the MDR-TB strains were in genomic clusters, indicating recent MDR-TB transmission. Most importantly, MDR-TB cases in three of the four large clades (>8 isolates) were spatially concentrated in three strain-specific hotspots (Figure 2). DISCUSSION/SIGNIFICANCE OF FINDINGS: With the combination of traditional epidemiological tools, geographical, and genomic methods, this study revealed multiple loci of transmission of specific MDR-TB clades within a single city. Identification of where and among whom MDR-TB is transmitted can inform the design of targeted interventions.
The disease burden of infectious diarrhea cannot be underestimated. Its seasonal patterns indicate that weather patterns may play an important role and have an important effect on it. The objective of this study was to clarify the relationship between temperature and infectious diarrhea, and diarrhea-like illness.
Distributed lag non-linear model, which was based on the definition of a cross-basis, was used to examine the effect.
Viral diarrhea usually had high incidence in autumn-winter and spring with a peak at -6°C; Norovirus circulated throughout the year with an insignificant peak at 8°C, while related bacteria usually tested positive in summer and peaked at 22°C. The lag-response curve of the proportion of diarrhea-like cases in outpatient and emergency cases revealed that at -6°C, with the lag days increasing, the proportion increased. Similar phenomena were observed at the beginning of the curves of virus and bacterial positive rate, showing that the risk increased as the lag days increased, peaking on days 16 and 9, respectively. The shape of lag-response curve of norovirus positive rate was different from others, presenting m-type, with 2 peaks on day 3 and day 18.
Weather patterns should be taken into account when developing surveillance programs and formulating relevant public health intervention strategies.
To investigate whether an after-school nutrition education (ASNE) programme can improve the nutrition knowledge and healthy eating behaviour of adolescents from economically disadvantaged families.
One-group pretest and posttest design. Nutrition knowledge and dietary intake were collected using a questionnaire, and anthropometric measurements were measured before and after the intervention. Nine components of healthy eating behaviour were assessed with reference to the Dietary Guideline of Taiwan. Pretest and posttest differences were analysed using generalised estimating equations.
Three after-school programmes in central and southern Taiwan. The ASNE programme comprised three monthly 1-h sessions (20–30-min lecture and 30–40-min interaction).
A total of 153 adolescents aged 10–15 years from economically disadvantaged families (seventy-eight elementary students and seventy-five junior high school students).
Elementary and junior high school students’ nutrition knowledge scores (range 0–6) increased by 0·28 (+ 5·7 %, P = 0·02) and 0·30 points (+ 6·18 %, P = 0·02), respectively, but their fruit intake decreased by 0·36 serving/d (–22·9 %, P = 0·02) and 0·29 serving/d (–18·9 %, P = 0·03), respectively. Junior high school students’ mean snacking frequency and fried food intake dropped to 0·75 d/week (–21·3 %, P = 0·008) and 0·10 serving/d (–28·8 %, P = 0·01), respectively.
Short-term ASNE programmes can increase nutrition knowledge and reduce snacking frequency and fried food intake despite a decrease in fruit intake among adolescents from economically disadvantaged families.
Background: Infection Prevention and Control (IPC) for Alberta Health Services and Covenant Health in the province of Alberta, Canada conducts surveillance for methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococcus (VRE) on all individuals admitted to acute-care and acute tertiary-care rehabilitation care facilities. Objective: The objective of this study was to determine the consistency and accuracy of infection decisions for MRSA and VRE. Methods: Surveillance cases of antibiotic-resistant organisms (AROs) collected using the provincial data entry surveillance platform between April 1, 2015, and March 31, 2017, across the province were reabstracted by infection control professionals and physicians using the NHSN infection definitions and compared to the original case severity decisions. Interrater agreement (Cohen’s ) and validity (sensitivity, specificity and predictive values) were calculated to compare the original and reabstracted infection decisions. Results: Collectively, 97% (87 of 90) of the IPC program staff and physicians who were initially invited re-abstracted 264 MRSA cases and 103 VRE cases within the review period. Provincially, 20% of the ARO cases reviewed (74 of 367) differed from the original infection decision. Among these 74 cases, 46 cases (34 MRSA and 12 VRE cases) changed from infection (original decision) to colonization (reabstracted decision) and 28 cases (21 MRSA and 7 VRE cases) changed from colonization to infection. The Cohen values for MRSA and VRE were 0.55 and 0.56, respectively, suggesting a moderate level of agreement for decisions made among IPC program staff. The sensitivity of the infection decision was higher with MRSA (86.5%) than for VRE (74.1%), meaning that there were more MRSA cases than VRE cases classified as infection in the original decision that remained infection following the review. Conclusions: Observed discordances on infection decisions were identified and may be attributed (1) to variations in the interpretation of the NHSN definitions, (2) to additional information that may have been available in the re-abstracted review compared to the original review, or (3) a difference in the information that was accessed to perform the original review compared to the reabstraction. This data-quality review provided an opportunity for IPC staff and physicians to become more familiar with infection definitions and such reviews will continue to be a regular process used to assess data quality within the IPC department.
Renal fibrosis is common especially in the elderly population. Recently, we found that vitamin D deficiency caused prostatic hyperplasia. This study aimed to investigate whether vitamin D deficiency promotes renal fibrosis and functional impairment. All mice except controls were fed with vitamin D-deficient (VDD) diets, beginning from their early life. The absolute and relative kidney weights on postnatal week 20 were decreased in VDD diet-fed male pups but not in female pups. A mild pathological damage was observed in VDD diet-fed male pups but not in females. Further analysis showed that VDD-induced pathological damage was aggravated, accompanied by renal dysfunction in 40-week-old male pups. An obvious collagen deposition was observed in VDD diet-fed 40-week-old male pups. Moreover, renal α-smooth muscle actin (α-SMA), a marker of epithelial–mesenchymal transition (EMT), and Tgf-β mRNA were up-regulated. The in vitro experiment showed that 1,25-dihydroxyvitamin D3 alleviated transforming growth factor-β1 (TGF-β1)-mediated down-regulation of E-cadherin and inhibited TGF-β1-evoked up-regulation of N-cadherin, vimentin and α-SMA in renal epithelial HK-2 cells. Moreover, 1,25-dihydroxyvitamin D3 suppressed TGF-β1-evoked Smad2/3 phosphorylation in HK-2 cells. These results provide experimental evidence that long-term vitamin D deficiency promotes renal fibrosis and functional impairment, at least partially, through aggravating TGF-β/Smad2/3-mediated EMT in middle-aged male mice.
The COVID-19 outbreak required the significantly increased working time and intensity for health professionals in China, which may cause stress signs.
From March 2–13 of 2020, 4,618 health professionals in China were included in an anonymous, self-rated online survey regarding their concerns on exposure to the COVID-19 outbreak. The questionnaires consisted of five parts: basic demographic information and epidemiological exposure; occupational and psychological impact; concerns during the episode; coping strategies; and the Huaxi Emotional-Distress Index (HEI).
About 24.2% of respondents experienced high levels of anxiety or/and depressive symptoms since the COVID-19 outbreak. Respondents who worried about their physical health and those who had COVID-19 infected friends or close relatives were more likely to have high HEI levels, than those without these characteristics. Further, family relationship was found to have an independent protective effect against high HEI levels. Their main concerns were that their families would not be cared for and that they would not be able to work properly. Compared to respondents with clear emotional problems, those with somewhat hidden emotional issues adopted more positive coping measures.
About a quarter of medical staff experienced psychological problems during the pandemic of COVID-19. The psychological impact of stressful events was related to worrying about their physical health, having close COVID-19 infected acquaintances and family relationship issues. Therefore, the psychological supprot for medical staff fighting in the COVID-19 pandemic may be needed.
Coronavirus disease 2019 (COVID-19) patients were classified into four clinical stages (uncomplicated illness, mild, severe and critical pneumonia) depending on disease severity. We aim to investigate the corresponding clinical, radiological and laboratory characteristics between different clinical stages. A retrospective, single-centre study of 101 confirmed patients with COVID-19 at Renmin Hospital of Wuhan University from 2 January to 28 January 2020 was enrolled; follow-up endpoint was on 8 February 2020. Clinical data were collected and compared during the course of illness. The median age of the 101 patients was 51.0 years and 33.6% were medical staff. Fever (68%), cough (50%) and fatigue (23%) are the most common symptoms. About 26% patients underwent the mechanical ventilation and 98% patients were treated with antibiotics. Thirty-seven per cent patients were cured and 11 died. On admission, the number of patients with uncomplicated illness, mild, severe and critical pneumonia were 2 [2%], 86 [85%], 11 [11%] and 2 [2%]. Forty-four of the 86 mild pneumonia progressed to severe illness within 4 days, with nine patients worsened due to critical pneumonia within 4 days. Two of the 11 severe patients improved to mild condition while three others deteriorated. Significant differences were observed among groups of different clinical stages in numbers of influenced pulmonary segments (6 vs. 12 vs. 17, P < 0.001). A significantly upward trend was witnessed in ground-glass opacities overlapped with striped shadows (33% vs. 42% vs. 55% vs. 80%, P < 0.001), while pure ground-glass opacities gradually decreased as disease progressed (45% vs. 35% vs. 24% vs. 13%, P < 0.001) within 12 days. Lymphocytes, prealbumin and albumin showed a downtrend as disease progressed from mild to severe or critical condition, an uptrend was found in white blood cells, C-reactive protein, neutrophils and lactate dehydrogenase. The proportions of serum amyloid A > 300 mg/l in mild, severe and critical conditions were 18%, 46% and 71%, respectively.
We genotyped six SNPs in the genes of p450 family among paranoid schizophrenics and normal controls. All subjects are unrelated Han Chinese. Three showed polymorphic, and no significant differences in allele or genotype frequencies were detected between patients and controls. Thus we obtained no evidence for the involvement of the polymorphisms in paranoid schizophrenia in the population investigated.
Dysfunctions of glutamatergic and GABAergic neurotransmission are two important hypotheses for the pathogenesis of schizophrenia. Thus, genes in the pathway are candidates for schizophrenia susceptibility. Phosphate-activated glutaminase (GLS), glutamine synthetase (GLUL), glutamic acid decarboxylase (GAD), GABA transaminase (ABAT) and succinic semialdehyde dehydrogenase (ALDH5A1) are five primary enzymes in glutamate and GABA synthetic and degradative pathway. In order to investigate the possible involvement of these genes in the development of paranoid schizophrenia, we genotyped 80 paranoid schizophrenics from northern China and 108 matched controls by polymerase chain reaction (PCR) and restriction fragment length polymorphisms (RFLP) methods or directly sequencing of PCR product. Seven SNPs were found to be polymorphic in the population investigated. No significant differences in the genotype distributions or allele frequencies between patients and controls were found. Therefore, we conclude the polymorphisms studied in the five genes do not play major roles in pathogenesis of paranoid schizophrenia in the population investigated.
We performed an association study between three SNPs in the genes of 14-3-3 family and paranoid schizophrenia. SNP rs983583 G/A in the YWHAZ gene showed significant association with paranoid schizophrenia. Our study indicated that the YWHAZ gene was a potential susceptibility gene for paranoid schizophrenia in the population studied.
The effects of bed roughness, isolated from those of bed permeability, on the vertical transport processes across the sediment–water interface (SWI) are not well understood. We compare the statistics and structure of the mean flow and turbulence in open-channel flows with a friction Reynolds number of 395 and a permeability Reynolds number of 2.6 over sediments with either regular or random grain packing at the SWI. The regular sediment interface is formed by cubic packing of spheres aligned with the mean-velocity direction. It is shown that, even in the absence of any bedform, the subtle details of the particle roughness alone can significantly affect the dynamics of turbulence and the time-mean flow. Such effects translate to large differences in penetration depths, apparent permeabilities, vertical mass fluxes and subsurface flow paths of passive scalars. The less organized distribution of mean recirculation regions near the interface with a random packing leads to a more isotropic form-induced stress tensor. The augmented wall-normal form-induced fluctuations play a significant role in increasing mixing and wall-normal mass and momentum exchange.
Human infections with avian influenza A (H7N9) virus are associated with exposure to poultry and live poultry markets, but the evidence of person-to-person transmission remains limited. This study reports a suspected person-to-person transmission of H7N9 virus, and explores what factors influenced this transmission.
We interviewed 2 patients with H7N9 infection and their family members as well as health-care workers. Samples from the patients and environments were tested by real-time reverse transcription-polymerase chain reaction.
The index patient became ill 5 to 6 days after his last exposure to the poultry bought in the market of Weimiao town. The second patient, the sister of the index patient, who had sustained intensive and unprotected close contact with the index patient, had no exposure to poultry. This study documents that the H7N9 virus was transmitted directly from the index patient to his sister.
Our findings suggest that person-to-person transmission may be associated with sustained close contact with the patient during his onset of early stage, when the H7N9 viral shedding increases sharply.
Evidence on the relationship between maternal Hb concentration and spontaneous abortion (SA) risk is limited and conflicting. The purpose of the study was to evaluate whether maternal preconception anaemia or high Hb concentration is associated with risk of SA.
A population-based cohort study established between 2013 and 2017.
Local maternal and child care service centres in each county.
In total, 3 971 428 women aged 20–49 years, who participated in National Free Pre-Pregnancy Checkups Project from 2013 to 2016 and successfully got pregnant before 2017 in rural China.
A total of 101 700 (2·56 %) women were recorded having SA, with highest SA rate in women with severe anaemia (4·58 %). Compared with women with Hb of 110–149 g/l, the multivariable-adjusted OR for SA was 1·52 (95 % CI: 1·25, 1·86) for women with Hb < 70 g/l, 0·92 (0·84, 1·01) for 70–99 g/l, 0·80 (0·77, 0·83) for 100–109 g/l, 1·11 (1·08, 1·15) for 150–159 g/l, 1·12 (1·04, 1·20) for 160–169 g/l and 1·02 (0·93, 1·12) for ≥ 170 g/l, respectively. An approximate U-shaped curve for the risk of SA with Hb concentrations was observed when Hb concentrations less than 145 g/l, above which the association plateaued (Pnon-linear < 0·001).
Severe anaemia and high Hb concentration before pregnancy were associated with an increased risk of SA. Women with mild anaemia prior to pregnancy had lower risk of SA. Underlying mechanisms need to be further studied.