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There is growing evidence that suggests the association of vitamin D status with the development and progression of heart failure (HF). The objective of the present study is to assess the impact of concentration of serum 25-hydroxyvitamin D (25(OH)D) on cardiac prognosis in patients with HF. Between 1 January 2015 and 31 December 2016, we consecutively recruited patients with HF. Patients were followed prospectively for a median duration of 1 year. Serum concentration of 25(OH)D was measured with competitive chemiluminescent immunoassay. The endpoints were cardiac events, including CVD death and rehospitalisation for worsening HF. Univariate and multivariable adjustments were performed with Cox proportional-hazard regression analyses. The 25(OH)D concentration was obtained in 343 patients with a median value of 17·4 (interquartile range 12·6–23·4) ng/ml. There were 102 cardiac events, including forty-three deaths and fifty-nine rehospitalisations. Multivariate Cox hazard analysis found that the serum concentration 25(OH)D was independently associated with cardiac events (hazard ratio 0·93, 95 % CI 0·88, 0·97) and CVD mortality (hazard ratio 0·83; 95 % CI 0·77, 0·89) after adjustment for confounding factors. We divided the HF patients into four groups according to the 25(OH)D quartiles. Kaplan–Meier analysis found that the patients with lower serum 25(OH)D concentration had a higher risk of cardiac events or CVD mortality than those with high serum 25(OH)D concentration (log-rank test P < 0·001 and P = 0·032). Decreased serum concentrations of 25(OH)D were associated with cardiac prognosis and CVD mortality in a Chinese population with HF independent of other baseline HF markers.
Toxigenic Clostridium difficile (C. difficile) carriers represent an important source in the transmission of C. difficile infection (CDI) during hospitalisation, but its prevalence and mode in patients with hepatic cirrhosis are not well established. We investigated longitudinal changes in carriage rates and strain types of toxigenic C. difficile from admission to discharge among hepatic cirrhosis patients. Toxigenic C. difficile was detected in 104 (19.8%) of 526 hepatic cirrhosis patients on admission, and the carriage status changed in a portion of patients during hospitalisation. Approximately 56% (58/104) of patients lost the colonisation during their hospital stay. Among the remaining 48 patients who remained positive for toxigenic C. difficile, the numbers of patients who were positive at one, two, three and four isolations were 10 (55.6%), three (16.7%), two (11.1%) and three (16.7%), respectively. Twenty-eight patients retained a particular monophyletic strain at multiple isolations. The genotype most frequently identified was the same as that frequently identified in symptomatic CDI patients. A total of 25% (26/104) of patients were diagnosed with CDI during their hospital stay. Conclusions: Colonisation with toxigenic C. difficile strains occurs frequently in cirrhosis patients and is a risk factor for CDI.
CrFeNiTix (x = 0.2, 0.3, 0.4, 0.5, and 0.6 molar ratio) compositionally complex alloys were fabricated by vacuum arc melting to investigate the microstructure, hardness, and compressive properties. The results revealed that CrFeNiTix alloys consisted of the principal face-centered cubic (FCC) phase and body-centered cubic (BCC) solid solution, with an amount of (Ni, Ti)-rich hexagonal close-packed phase. CrFeNiTix alloys exhibited the typical dendrite. Ti0.2 and Ti0.3 alloys were composed of FCC and BCC solid solutions in the dendrite, as well as ε (Ni3Ti) and R (Ni2.67Ti1.33) phases in the inter-dendrite, simultaneously. For Ti0.4, Ti0.5, and Ti0.6 alloys, (Fe, Cr)-rich solid solution separated out and ε phase transformed into R phase gradually. Meanwhile, TEM analysis indicated that Ti0.4 alloy matrix consisted of the principal FCC phase containing (Ni, Ti)-rich intragranular nanoprecipitates. The hardness values of CrFeNiTix alloys were increased with the addition of Ti content and the high compressive strength of CrFeNiTix alloys was maintained, which was attributed to the solid solution strengthening and precipitation hardening.
To explore the direct and indirect associations of dietary patterns with hypertension using structural equation modelling (SEM).
Factor analysis with varimax rotation was used to classify different dietary patterns and SEM was employed to investigate the associations of dietary patterns with hypertension. Total cholesterol to HDL-cholesterol (TC:HDL-C) ratio and LDL-cholesterol to HDL-cholesterol (LDL-C:HDL-C) ratio were used as observed indicator variables of the lipid latent variable. Waist circumference, body fat percentage and BMI, which were associated with hypertension, were used as observed indicator variables of the obesity latent variable.
International Chronic Disease Cohort (ICDC) that began in 2005 with the purpose of describing the frequency and determinants of chronic diseases in Jilin Province, China.
A total of 1492 adults (40–79 years) were enrolled in the baseline study from August 2010 to August 2011.
Hypertension prevalence in our study population was 34·9 %. It was found that the wine pattern, condiment pattern, obesity latent variable, lipid latent variable, glucose, age and family history of hypertension were factors that had an association with hypertension via SEM, and the corresponding coefficients were 0·056, 0·011, 0·230, 0·281, 0·098, 0·232 and 0·116, respectively.
The wine pattern and lipid latent variable had positive direct associations with hypertension. The condiment pattern had a positive indirect association with hypertension via the obesity latent variable. The vegetables pattern, modern pattern and snack pattern were not associated with hypertension.
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.
The codeposition characteristics of Si–B–N ceramics from the SiCl4–NH3–BCl3–H2–Ar system at lower temperatures and phase transformation of as-prepared Si–B–N ceramics at temperatures from 1200 to 1800 °C were investigated. Thermodynamic analysis results indicated that the BN + Si3N4 dual phase region existed from 800 to 1200 °C and that 800 °C was an optimum deposition temperature to deposit Si–B–N ceramic coating. Deposition efficiencies at equilibrium for Si3N4 and BN were high, particularly at temperatures below 1000 °C. Pressure and dilution ratio of H2 had little influence on deposition efficiencies of BN and Si3N4 at 800 °C. The amorphous Si–B–N ceramic coatings were successfully deposited at 800 °C from the same precursor system and contained N–B and N–Si bonds by XPS analysis. It kept amorphous below 1600 °C in N2 and partly transformed to α/β-Si3N4 when heat treated at 1600 °C in N2 for 2 h. These results demonstrated that the composite Si–B–N ceramics could be fabricated at 800 °C and used below 1600 °C.
Multimaterial bioprinting technologies offer promising avenues to create mini-organ models with enhanced tissue heterogeneity and complexity. This article focuses on the application of three-dimensional bioprinting to fabricate organ-on-a-chip systems for in vitro drug testing and screening. We illustrate the capabilities and limitations of a bioprinting approach compared to microfabrication in constructing an organ-on-a-chip device. Further, we propose strategies in multimaterial integration for printing microphysiological tissue models. With these analyses, key challenges and future directions are highlighted.
Previous studies have investigated the association between dietary inflammatory potential and the development of cancer. For breast cancer the results have been equivocal. The present study aimed to investigate whether higher Dietary Inflammatory IndexTM (DII) scores were associated with increased risk of breast cancer among Chinese women. A total of 867 cases and 824 controls were recruited into the present case–control study from September 2011 to February 2016. DII scores were computed based on baseline dietary intake assessed by a validated 81-item FFQ. The OR and 95 % CI were assessed by multivariable logistic regression after adjusting for various potential confounders. DII scores in this study ranged from −5·87 (most anti-inflammatory score) to +5·71 (most proinflammatory score). A higher DII score was associated with a higher breast cancer risk (adjusted ORquartile 4 v. 1 2·28; 95 % CI 1·71, 3·03; adjusted ORcontinuous 1·40; 95 %CI 1·25, 1·39). In stratified analyses, positive associations also were observed except for underweight women or women with either oestrogen receptor+ or progesterone receptor+ status (but not both). Results from this study indicated that higher DII scores, corresponding to more proinflammatory diets, were positively associated with breast cancer risk among Chinese women.
The regional part of the current BeiDou navigation satellite system (BDS) consists of five Geostationary Earth Orbit (GEO) satellites, five Inclined Geosynchronous Satellite Orbit (IGSO) satellites and four Medium Earth Orbit (MEO) satellites. We examined three algorithms for BDS velocity estimation. In addition, the performance of velocity estimation using different BDS satellite combinations was analysed. Static tests demonstrated that velocity precision using Raw Doppler (RD) measurements was of the order of centimetres per second, whereas the carrier-phase-Derived Doppler (DD) measurements and Time-Differenced Carrier Phase (TDCP) method provided accuracies of the order of millimetres per second. Because of the irregularity of the satellites' distribution, three peaks exist on the north component in the 24-hour velocity series. Besides, the GEO satellites contribute significantly in velocity estimation and the satellites' geometry condition seriously declined when excluding GEO satellites. In kinematic tests, the root mean square of the velocity error derived by DD and TDCP both attained the centimetre per second level. Moreover, the precision of velocity determination with these three methods was degraded by the sudden acceleration of the vehicle.
As a kind of flash heat source, intense pulsed ion beam (IPIB) can be used for material surface modification. The ablation effect has important influence on interaction between IPIB and material. Therefore, the understanding of ablation mechanism is of great significance to IPIB application. In this work, pure zinc targets were irradiated and ablated by IPIB. In the ablation process under the different ion beam energy densities, the ablation products were collected by a monocrystalline silicon substrate. By analyzing the ablation products with scanning electron microscope and energy-dispersive spectrometer, the surface morphology, and the spatial distribution of ablation products quantity were obtained. The results are useful for clearing the ablation process and the influence of beam parameter on the ablation effect.
To promote the energy density of lithium-ion battery, the sulfur-based cathode has attracted extensive attention because of its high specific capacity of 1672 mAh g-1 and its high abundance. However, the sulfur shuttling effects and the loss of active material during lithiation hinder its commercial application. To tackle these issues, we synthesized a stable copolymer-sulfur composite by chemically binding sulfur. The composite with 86% sulfur content was prepared using 1,3-diethynylbenzen and sulfur particles via scalable invers vulcanization. The sulfur content in copolymer sulfur was achieved as high as 86%. Our copolymer-sulfur composite cathode showed excellent cycling performance with a specific capacity of 454 mAh g-1 at 0.1 C after 300 cycles. We demonstrate that the organosulfur-DEB units in the copolymer-sulfur composite serve as the ‘plasticizer’ to effectively prevent the polysulfide shuttling.
Cerebral small vessel disease (SVD) is the common cause of cognitive decline in the old population. MRI can be used to clarify its mechanisms. However, the surrogate markers of MRI for early cognitive impairment in SVD remain uncertain to date. We investigated the cognitive impacts of cerebral microbleeds (CMBs), diffusion tensor imaging (DTI), and brain volumetric measurements in a cohort of post-stroke non-dementia SVD patients.
Fifty five non-dementia SVD patients were consecutively recruited and categorized into two groups as no cognitive impairment (NCI) (n = 23) or vascular mild cognitive impairment (VaMCI) (n = 32). Detailed neuropsychological assessment and multimodal MRI were completed.
The two groups differed significantly on Z scores of all cognitive domains (all p < 0.01) except for the language. There were more patients with hypertension (p = 0.038) or depression (p = 0.019) in the VaMCI than those in the NCI group. Multiple regression analysis of cognition showed periventricular mean diffusivity (MD) (β = −0.457, p < 0.01) and deep CMBs numbers (β = −0.352, p < 0.01) as the predictors of attention/executive function, which explained 45.2% of the total variance. Periventricular MD was the independent predictor for either memory (β = −0.314, p < 0.05) or visuo-spatial function (β = −0.375, p < 0.01); however, only small proportion of variance could be accounted for (9.8% and 12.4%, respectively). Language was not found to be correlated with any of the MRI parameters. No correlation was found between brain atrophic indices and any of the cognitive measures.
Arteriosclerotic CMBs and periventricular white matter disintegrity seem to be independent MRI surrogated markers in the early stage of cognitive impairment in SVD.
This paper presents a parameterized gait generator based on linear inverted
pendulum model (LIPM) theory, which allows users to generate a natural gait
pattern with desired step sizes. Five types of zero moment point (ZMP)
components are proposed for formulating a natural ZMP reference, where ZMP moves
continuously during single support phases instead of staying at a fixed point in
the sagittal and lateral plane. The corresponding center of mass (CoM)
trajectories for these components are derived by LIPM theory. To generate a
parameterized gait pattern with user-defined parameters, a gait planning
algorithm is proposed, which determines related coefficients and boundary
conditions of the CoM trajectory for each step. The proposed parameterized gait
generator also provides a concept for users to generate gait patterns with
self-defined ZMP references by using different components. Finally, the
feasibility of the proposed method is validated by the experimental results with
a teen-sized humanoid robot, David, which won first place in the sprint event at
the 20th Federation of International Robot-soccer Association (FIRA) RoboWorld
Zircon U–Pb dating and whole-rock geochemical analysis have been performed on Late Jurassic – Early Cretaceous intrusive rocks of the Ulanhot area, NE China, with the aim of constraining the tectonic evolution of the central and southern Da Xingan Range. Zircon U–Pb dating indicates that Late Jurassic – Early Cretaceous magmatic events experienced four stages at: c. 155 Ma; c. 144 Ma; 135–130 Ma; and c. 126 Ma. The c. 155 Ma magmatic event consists of quartz diorite and granite-porphyryp with the geochemical characteristic of high Sr and Sr/Y or high A/CNK (1.38), implying the primary magma was derived from partial melting of a thickened lower crust which induced the closure of the Mongol–Okhotsk Ocean. The c. 144 Ma magmatic event consists of quartz monzodiorite with the geochemical characteristics of alkaline series, and indicates the delamination of a thickened crust. The 135–130 Ma magmatic event consists of syenogranite and granite-porphyry with characteristics of both I-type and A-type granites, which induced both the subduction of the Palaeo-Pacific oceanic plate and the post-orogenic extension of the Mongol–Okhotsk Orogenic Belt. The c. 126 Ma magmatic event consisted of highly fractionated I-type biotite granite and alkaline series gabbro, marking the end of the Mongol–Okhotsk Orogen, and implying that the study area was controlled by the circum-Pacific tectonic system during this stage.
We report new field observations, zircon U–Pb ages and geochemical data for the discrete members of the Zhaheba ophiolite complex in northeastern Junggar of the Central Asian Orogenic Belt (CAOB) with the aim to understand the accretion process of the eastern Junggar terrane. The zircon age data reveal that the cumulates of the Zhaheba ophiolite crystallized at ~485 Ma while the volcanic sequences erupted at ~400 Ma. Thus, the volcanic sequences are not members of the Zhaheba ophiolite. Chromian spinels from the serpentinite have comparable elemental compositions to those of spinels from MORB-type ophiolites. Similarly, the rift affinity of clinopyroxene and positive zircon εHf(t) (13–20) and mantle δ18O (+5.37‰) values of the cumulates imply that the cumulates crystallized from primitive magmas derived from a depleted mantle source. Elemental and Nd isotopic compositions indicate that the basalts in the Zhaheba area were derived from partial melting of a mantle wedge metasomatized by adakitic melts and/or subduction-related fluids. The data presented in this contribution, together with previous studies, indicate that the Zhaheba–Almantai and Kelameili ophiolites were MORB-type, which implies that there were at least two mid-ocean ridges during Ordovician to early Devonian times in the Junggar Ocean. In the earlier stage, intra-oceanic subduction led to the formation of the intra-oceanic arc, and then the Kelameili ophiolite accreted to an intra-oceanic accretionary wedge. In the later stage, the Zhaheba–Almantai ophiolite accreted to the accretionary wedge along the southern margin of the Iritish suture zone during the roll-back of the subduction zone from north to south.
The morphology, chemistry and phylogenetic relationships of Chinese populations
of Bulbothrix are described. Nine species, including two new
species B. mammillaria Y. Y. Zhang & Li S. Wang sp.
nov. and B. lacinia Y. Y. Zhang & Li S. Wang sp.
nov., and two newly recorded for the flora, B. scortella and
B. meizospora, are reported. Bulbothrix
mammillaria can be recognized by the sparse cilia that are reduced to a
bulbate structure and the broad lobes (3–11 mm). Bulbothrix
lacinia differs from other species of the genus by dark brown,
spherical to short-cylindrical isidia and common lacinulae on the upper surface.
Phylogenetic relationships of currently known ITS sequences from
Bulbothrix were inferred to assess the affinities of the
new species. A key to all known species from China is presented.
This paper investigates properties of the percentile residual life (PRL) function for a single component and for a k-out-of-n system. The shape of the component PRL function can be determined by the component failure rate function. The intimate relations between these two functions are studied first. Then we generalize the results to a k-out-of-n system by assuming independent and identical components. We show that the behavior of the PRL for a k-out-of-n system is quite different from the component PRL. We also find that for series and parallel systems, the location of the change point of the PRL is monotone in the number of components in a system.
Being connected “anywhere anytime” has become a way of life for much of the world's population. Thanks to major technological advances in internet, wireless communication, video technology, silicon manufacturing, etc., our mobile devices have become not only faster and more powerful, but also smaller and sleeker. With the popularity of rich media on the rise, the no. 1 data traffic over the mobile network is attributed to video. That is the reason why we depict the Freeman Dyson's book title “From Eros to Gaia.” Equipped with rich media capabilities, our mobile devices enable a completely different storytelling experience unlike anything the human race has experienced before. In this paper, we review the latest technological evolutions in the wireless space and in the video space, namely long-term evolution and high-efficiency video coding, respectively. We then discuss how these advanced technologies impact our way of life at present and in years to come.
Tea consumption has inconsistently been shown to be associated with the risk of type 2 diabetes (T2D). The aim of the present study was to conduct a dose–response meta-analysis of cohort studies assessing the association between consumption of tea and risk of developing T2D. Pertinent studies were identified by searching PubMed, Web of Science and EMBASE through 31 March 2013. A total of sixteen cohorts from fifteen articles that reported 37 445 cases of diabetes among 545 517 participants were included. A significant linearly inverse association between tea consumption and T2D risk was found (P for linear trend = 0·02). An increase of 2 cups/d in tea consumption was found to be associated with a 4·6 (95 % CI 0·9, 8·1) % reduced risk of T2D. On the basis of the dose–response meta-analysis, the predicted relative risks of diabetes for 0, 1, 2, 3, 4, 5 and 6 cups of tea consumed per d were 1·00 (referent), 0·97 (95 % CI 0·94, 1·01), 0·95(95 % CI 0·92, 0·98), 0·93 (95 % CI 0·88, 0·98), 0·90 (95 % CI 0·85, 0·96), 0·88 (95 % CI 0·83, 0·93) and 0·85 (95 % CI 0·80, 0·91), respectively. There was a statistically significant heterogeneity within the selected studies (Q= 45·32, P< 0·001, I2= 60·3 %). No evidence of substantial small-study bias was found (P= 0·46). Our findings suggest that tea consumption could be linearly inversely associated with T2D risk. Future well-designed observational studies that account for different characteristics of tea such as tea types, preparation methods and tea strength are needed to fully characterise such an association.