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Predicting the magnitude of the annual seasonal peak in influenza-like illness (ILI)-related emergency department (ED) visit volumes can inform the decision to open influenza care clinics (ICCs), which can mitigate pressure at the ED. Using ILI-related ED visit data from the Alberta Real Time Syndromic Surveillance Net for Edmonton, Alberta, Canada, we developed (training data, 1 August 2004–31 July 2008) and tested (testing data, 1 August 2008–19 February 2014) spatio-temporal statistical prediction models of daily ILI-related ED visits to estimate high visit volumes 3 days in advance. Our Main Model, based on a generalised linear mixed model with random intercept, incorporated prediction residuals over 14 days and captured increases in observed volume ahead of peaks. During seasonal influenza periods, our Main Model predicted volumes within ±30% of observed volumes for 67%–82% of high-volume days and within 0.3%–21% of observed seasonal peak volumes. Model predictions were not as successful during the 2009 H1N1 pandemic. Our model can provide early warning of increases in ILI-related ED visit volumes during seasonal influenza periods of differing intensities. These predictions may be used to support public health decisions, such as if and when to open ICCs, during seasonal influenza epidemics.
Nucleos(t)ide analogues (NAs) are widely used for antiviral therapy in patients with chronic hepatitis B (CHB), but real-world data on treatment patterns and long-term clinical outcomes are not always available. Using data from electronic medical records between January 2011 and December 2016 in Shanghai, China, we evaluated patient characteristics, treatment patterns and clinical outcomes in patients with CHB. There were 6688 patients in the study cohort. The incidences of cirrhosis and hepatocellular carcinoma (HCC) were 41.0‰ and 6.8‰ person-years, respectively. There were more cirrhosis and HCC cases among patients who had shorter NA treatment duration (<365 days), or who were less compliant (<80%). In addition, increased risk of cirrhosis and HCC was observed in patients who did not achieve hepatitis B surface antigen (HBsAg) loss/seroconversion. Moreover, patients with cirrhosis developed after antiviral treatments had a higher incidence of HCC (adjusted hazard ratio 15.86, 95% confidence interval 7.35–34.24). Good compliance with treatment and longer treatment duration significantly decreased the risk of developing cirrhosis and HCC. HBsAg loss seemed to be a protective factor for cirrhosis/HCC in NAs-treated patients with CHB, and cirrhosis was a confirmed risk factor for HCC development as expected.
Previous studies have demonstrated that type 1 diabetes mellitus (T1DM) could be triggered by an early childhood infection. Whether maternal infection during pregnancy is associated with T1DM in offspring is unknown. Therefore, we aimed to study the association using a systematic review and meta-analysis. Eighteen studies including 4304 cases and 25 846 participants were enrolled in this meta-analysis. Odds ratios (ORs) and 95% confidence intervals (CIs) were synthesised using random-effects models. Subgroup analyses and sensitivity analyses were conducted to assess the robustness of associations. Overall, the pooled analysis yielded a statistically significant association between maternal infection during pregnancy and childhood T1DM (OR 1.31, 95% CI 1.07–1.62). Furthermore, six studies that tested maternal enterovirus infection showed a pooled OR of 1.54 (95% CI 1.05–2.27). Heterogeneity from different studies was evident (I2 = 70.1%, P < 0.001) and was mainly attributable to the different study designs, ascertaining methods and sample size among different studies. This study provides evidence for an association between maternal infection during pregnancy and childhood T1DM.
We present a scheme of electron beam radiography to dynamically diagnose the high energy density (HED) matter in three orthogonal directions simultaneously based on electron Linear Accelerator. The dynamic target information such as, its profile and density could be obtained through imaging the scattered electron beam passing through the target. Using an electron bunch train with flexible time structure, a very high temporal evolution could be achieved. In this proposed scheme, it is possible to obtain 1010 frames/second in one experimental event, and the temporal resolution can go up to 1 ps, spatial resolution to 1 µm. Successful demonstration of this concept will have a major impact for both future inertial confinement fusion science and HED physics research.
A comparative study of the effect of dietary nitrogen (N) content [Low: 11·0; Medium-Low (MLow): 16·7; Medium-High (Mhigh): 23·1; High: 29·2 N g/kg dry matter (DM)] on apparent digestibilities, rumen fermentation and N balance was conducted in coarse wool Tibetan sheep and Gansu Alpine fine-wool sheep at Wushaoling in the northeast of the Qinghai-Tibetan Plateau. It was hypothesized that responses would differ between breeds and that responses would favour Tibetan over fine-wool sheep at low N intakes. Eight wethers [four Tibetan sheep and four fine-wool sheep, 20–24 months old; body weight ± standard deviation was 52 ± 3·2 kg] were used in two concurrent 4 × 4 Latin square designs. Dry matter, organic matter, neutral detergent fibre and acid detergent fibre digestibilities were higher in Tibetan than fine-wool sheep when fed the Low, MLow and High N diets while N retention was higher when the animals were fed the Low and MLow N diets. Tibetan sheep had a higher rumen pH than fine-wool sheep; however, total volatile fatty acids were similar between breeds. Molar proportions of acetate were higher but propionate and butyrate lower in Tibetan than fine-wool sheep. In addition, Tibetan sheep had higher concentrations of ruminal free amino acid-N and soluble protein-N than fine-wool sheep. Plasma and saliva urea-N concentrations were higher in Tibetan than fine-wool sheep when supplied with the Low N diet. It was concluded that Tibetan sheep were better able to cope with low N feed than fine-wool sheep because of the higher N retention and higher DM and fibre digestibilities with Low and MLow diets.
Hemin immobilized reduced graphene(HGN) has been investigated to be an outstanding enzymatic catalysis in detection important molecular recently. In this work, two "clean" methods to prepare HGN through π-π stack were charactered by UV-vis spectra, TEM images, and δ-potential. The enzymatic catalysis of both materials was compared by catalytic hydrogen peroxide to oxidize pyrogallol. The colorimetric result shows HGN attached before reduction has stronger catalytic ability than the one after reduction. The optimized HGN was then used as an electrochemical biosensor to determine L-tyrosine levels. The cyclic voltammetry (CV) tests were carried out for the bare glass carbon electrode (GCE), and the optimized hemin-reduced graphene electrode (HGN1/GCE). The HGN1/GCE based biosensor exhibits a Tyrosine detection linear range from 5×10-7 M to 4×10-5 M with a detection limitation of 7.5×10-8 M at signal noise ratio (S/N) of 3. In comparison with other biosensor, electrochemical biosensors are easy-fabricated, easy-controlled, and cost-effective. Compared with other materials, the hemin-reduced graphene based biosensors demonstrate higher stability, a broader detection linear range, and better detection sensitivity. The study of oxidation scheme reveals that reduced graphene enhanced the electron transfer between electrode and hemin. Meanwhile, the hemin groups effectively electrocatalyzed the oxidation of tyrosine. This study contributes to a widespread clinical application of nanomaterial based biosensor devices with a broader detection linear range, improved stability, enhanced sensitivity, and reduced costs.
Photoembossing is a technique used to create relief structures using a
patterned contact photo-mask exposure and a thermal development step.
Typically, the photopolymer consists of a polymer binder and a monomer in a
1/1 ratio together with a photo-initiator which results in a solid and
non-tacky material at room temperature. Here, new mixtures for
photoembossing are presented which are potentially biocompatible. A polymer
binder such as poly (methyl methacrylate) with triacrylate monomer and
biocompatible photo-initiator Irgacure 369 is used. Photopolymer films
produced are successfully embossed with height of relief structures
controlled by UV dosage and developing temperature. Furthermore, the
photopolymer blend is electrospun to form fibres with diameters of 5 μm
which are then photoembossed. The photoembossed fibres showed homogenous
reproducible surface textures. Biocompatibility is evaluated by culturing
human umbilical vein endothelial cells (HUVECs) on films of this
photopolymer blend. The study shows that photoembossing is a feasible method
of producing surface texturing on both films and electrospun fibres for
tissue engineering applications.
Teflon amorphous fluoropolymer (TAF) multi-walled carbon nanotube (MWCNT) suspensions have the potential for creating conductive coatings on insulating films for numerous applications. However, there are few studies on polymer MWCNT suspension properties and even fewer that use Teflon. To define mechanical and electrical property relationships, bilayer films of TAF-MWCNT were created with differing concentrations of MWCNTs. Nanoindentation revealed that addition of 8 wt% MWCNTs to TAF increased the elastic modulus by about 25% and hardness by about 15%. Conducting indentation showed 8 wt% MWCNT films exhibit uniform stable conductance once indentation depth exceeds several hundred nanometers. Films with lower concentrations of CNTs were insulating. The two techniques provide a unique description of structure property relationships in this suspension film system.
In Western countries, a history of major depression (MD) is associated with reports of received parenting that is low in warmth and caring and high in control and authoritarianism. Does a similar pattern exist in women in China?
Received parenting was assessed by a shortened version of the Parental Bonding Instrument (PBI) in two groups of Han Chinese women: 1970 clinically ascertained cases with recurrent MD and 2597 matched controls. MD was assessed at personal interview.
Factor analysis of the PBI revealed three factors for both mothers and fathers: warmth, protectiveness, and authoritarianism. Lower warmth and protectiveness and higher authoritarianism from both mother and father were significantly associated with risk for recurrent MD. Parental warmth was positively correlated with parental protectiveness and negatively correlated with parental authoritarianism. When examined together, paternal warmth was more strongly associated with lowered risk for MD than maternal warmth. Furthermore, paternal protectiveness was negatively and maternal protectiveness positively associated with risk for MD.
Although the structure of received parenting is very similar in China and Western countries, the association with MD is not. High parental protectiveness is generally pathogenic in Western countries but protective in China, especially when received from the father. Our results suggest that cultural factors impact on patterns of parenting and their association with MD.
To investigate the effect of dietary allicin on health and growth performance of weanling piglets, at 21 days of age. Two hundred and twenty-five piglets were weaned and randomly allocated into five groups. Piglets in the control group were fed diets supplemented with antibiotics. Those in the treatment groups were fed diets without antibiotics, but supplemented with allicin product (25% pure allicin oil) in the proportion of 0.10 g/kg, 0.15 g/kg, 0.20 g/kg and 0.25 g/kg in the diet, respectively. During the 28 days of the experiment, average daily weight gain increased linearly (P < 0.0001) and quadratically (P = 0.0014) as the level of dietary allicin increased. The feed gain ratio decreased linearly (P < 0.0001) and quadratically (P < 0.0001). As the dietary allicin level increased, the incidence of diarrhoea in the treatment piglets, especially female piglets decreased linearly (P = 0.0003) and tended to decrease quadratically (P = 0.0716). The number of flies alighting on the surface of the faeces of the piglets at each counting time point decreased linearly (P < 0.0001), quadratically (P < 0.0001) and cubically (P < 0.0001) as the dietary allicin level increased. In conclusion, supplementation of the diet with allicin may improve growth performance, reduce the incidence of diarrhoea and possibly improve their local environmental conditions by reducing the attractiveness of faeces to flies.
The mechanical properties of arrays of nominally vertically aligned carbon nanotubes, often referred to as turfs, have been measured using nanoindentation and the electrical properties have been measured using electrical contact resistance (ECR) nanoindentation. The elastic properties do not vary significantly between the top and the bottom of the same carbon nanotube turf. Within a single turf the lateral spatial variation is less than 10% when volumes of μm's are probed with the indenter, indicating that each turf can be treated mechanically as continuum on this scale. The electrical properties vary significantly within a single turf on the same scale. This suggests that the use of average mechanical properties for a given vertically aligned turf should be suitable for design purposes without the need to account for spatial variation in structure, and variations in mechanical properties on the micrometer scale are not dependent on spatially distinct defects. However, local contact behavior appears to dominate the electrical behavior on this same length scale.
In this study, we performed nanoindentation experiments on two sets of silicon nanolines (SiNLs) of widths 24 nm and 90 nm, respectively, to investigate the mechanical behavior of silicon structures at tens of nanometer scale. The high height-to-width aspect ratio (∼15) SiNLs were fabricated by an anisotropic wet etching (AWE) method, having straight and nearly atomically flat sidewalls. In the test, buckling instability was observed at a critical load, which was fully recoverable upon unloading. It was found that friction at the contact between the indenter and SiNLs played an important role in the buckling response. Based on a finite element model (FEM), the friction coefficient was estimated to be in a range of 0.02 to 0.05. The strain to failure was estimated to range from 3.8% for 90 nm lines to 7.5% for 24 nm lines.
InAsSb quantum dot (QD) lasers are promising light sources with emission wavelengths beyond 2μm as recently demonstrated. We report the first detailed atomic force microscope (AFM) characterization of uncapped InAsSb quantum dots self-assembled on GaAs/In0.53Ga0.47As layers. These quantum dot structures are grown on (100) InP substrates by metal organic chemical vapor deposition (MOCVD). Growth conditions are chosen to maximize photoluminescence intensity and to obtain high output powers from Fabry-Perot lasers with one stack of InAsSb QDs. Conductive AFM is employed to simultaneously study topography, current image, and current-voltage (I-V) characteristics from various InAs1-ySby QDs with y varied between 0 and 0.25. Typical dot density is 4–5×1010/cm2 and dots are estimated to have a lateral dimension at the base of ∼40nm and a height of 2–5nm. I-V characteristics measured from individual InAsSb QDs are compared to those from InAs QDs. Also reported are electronic properties including energy band gaps of InAs and InAsSb QDs.
Based on the high-resolution, high signal-to-noise ratio spectra collected with the coudé echelle spectrograph attached to the 2.16m telescope at Beijing Astronomical Observatory, we determined the chemical abundance patterns for a sample of six planet-harboring stars. The result is used to investigate the connection between giant planet and high metallicity and to probe the influence of this process on other elements.
Partial (DNA) sequences are presented for 2 nuclear (18S and 28S rRNA genes) and 2 mitochondrial (12S rRNA and ND1 genes) loci for 5 species belonging to the Schistosoma japonicum, S. sinensium and S. indicum groups of Asian Schistosoma. Fresh field isolates were collected and cultured for the following taxa: S. incognitum (S. indicum group, central Thailand), S. mekongi (S. japonicum group, southern Laos), S. ovuncatum (S. sinensium group, northern Thailand), S. spindale (S. indicum group, northeast Thailand and central Thailand isolates) and S. sinensium (S. sinensium group, Sichuan Province, China). This represents the first published DNA sequence data for S. ovuncatum and for S. sinensiums.s. from the type locality in China. The paper also presents the first sequence data at the above loci for S. incognitum (except for the 28S sequences) and S. sinensium. Congruence was observed between the phylogenies estimated for each locus, although the relationships of S. incognitum were not so well resolved. Fitch–Margoliash, maximum likelihood (ML) and maximum parsimony methods were used to estimate the phylogenies and the agreement between them was similar to that observed between loci. The ML tree was considered to best represent the data and additional 28S sequences (taken from the GenBank), for S. haematobium, S. japonicum, S. mansoni and Orientobilharzia turkestanicum, were used to construct an overall phylogeny. The S. indicum group taxa showed considerable divergence from the other Asian species and closest affinity with the African group. S. ovuncatum and S. sinensium appeared as sister taxa but their status as sibling species remained supported. The findings are discussed in the context of phylogeographical hypotheses for the origin of Schistosoma. An Asian origin for Schistosoma is also considered.
Acting as a pilot of the Square Kilometer Array (SKA), the Five hundred meter Aperture Spherical Telescope (FAST) has been proposed for construction in the unique karst area of southwest China. FAST is of Arecibo-type with rather a number of innovations, among which the active main spherical reflector shows fascinating. Furthermore, the feed cabin is supported and moved by cables controlled by computer, which avoids a heavy and expensive focal pointing system. With the effective aperture of 300 m, a large sky coverage, and a broad bandwidth (200 to 2000 MHz), possible capability up to 5 ∼8 GHz, FAST will be the world's largest single dish and perform markedly role in radio astronomy.
A Five hundred meter Aperture Spherical Telescope (FAST) is proposed to be built in the unique karst area of southwest China, and will act, in a sense, as a prototype for the Square Kilometer Array (SKA). It will be over twice as large as the Arecibo telescope coupled with much wider sky coverage. Some results from site surveys for such a SKA concept are briefly reported. Technically, FAST is not simply a copy of the existing Arecibo telescope but has rather a number of innovations. Firstly, the proposed main spherical reflector, by conforming to a paraboloid of revolution in real time through actuated active control, enables the realization of both wide bandwidth and full polarization capability while using standard feed design. Secondly, a feed support system which integrates optical, mechanical and electronic technologies will effectively reduce the cost of the support structure and control system. Pre-research on FAST has become a key project in the CAS.