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Radiation exposure during paediatric cardiac catheterisation procedures should be minimised to “as low as reasonably achievable”. The aim of this study was to evaluate the effectiveness of a modified radiation safety protocol in reducing patient dose during paediatric interventional cardiac catheterisation.
Radiation dose data were retrospectively extracted from January 2014 to December 2015 (Standard group) and prospectively collected from January 2016 to December 2017 (Low-dose group) after implementation of a modified radiation safety protocol. Both groups included five most common procedures: atrial septal defect closure, patent ductus arteriosus closure, perimembranous ventricular septal defect closure, pulmonary valvuloplasty, and supraventricular tachycardia ablation.
Median air Kerma was 48.4, 50.5, 29.75, 149, 218, and 12.9 mGy for atrial septal defect closure, pulmonary valvuloplasty, patent ductus arteriosus closure <20 kg, ventricular septal defect closure <20 kg, ventricular septal defect closure ≧20 kg, and supraventricular tachycardia ablation in Standard group, respectively, which significantly decreased to 18.75, 20.7, 11.5, 41.9, 117, and 3.3 mGy in Low-dose group (p < 0.05). This represents a reduction in dose to each patient between 46 and 74%. Among five procedural types in Low-dose group, dose of ventricular septal defect closure was the highest with median air Kerma of 62.5 mGy, dose area product of 364.7 μGy.m2, and dose area product per body weight of 21.5 μGy.m2/kg, respectively, along with the longest fluoroscopy time of 9.9 minutes.
We provided a feasible radiation safety protocol with specific settings on a case-by-case basis. Increasing awareness and adequate training of a practical radiation dose reduction program are essential to improve radiation protection for children.
We assessed inheritance of resistance to sugarcane brown rust (Puccinia melanocephala) in selfing F1 populations of wild sugarcane germplasm Erianthus rockii ‘Yundian 95-19’ and E. rockii ‘Yundian 95-20’. We tested parent and selfing F1 individuals for the brown rust resistance gene, Bru1, that has been shown to confer resistance to brown rust in sugarcane. The Bru1 gene was not detected in E. rockii ‘Yundian 95-19’, E. rockii ‘Yundian 95-20’ or their selfing F1 individuals, and we found there was segregation of resistance in the two selfing F1 populations (segregation ratio: 3:1). The results confirmed resistance in E. rockii ‘Yundian 95-19’ and E. rockii ‘Yundian 95-20’ to sugarcane brown rust is controlled by a novel, single dominant gene.
This study proposes two multimodal frameworks to classify pathological voice samples by combining acoustic signals and medical records. In the first framework, acoustic signals are transformed into static supervectors via Gaussian mixture models; then, a deep neural network (DNN) combines the supervectors with the medical record and classifies the voice signals. In the second framework, both acoustic features and medical data are processed through first-stage DNNs individually; then, a second-stage DNN combines the outputs of the first-stage DNNs and performs classification. Voice samples were recorded in a specific voice clinic of a tertiary teaching hospital, including three common categories of vocal diseases, i.e. glottic neoplasm, phonotraumatic lesions, and vocal paralysis. Experimental results demonstrated that the proposed framework yields significant accuracy and unweighted average recall (UAR) improvements of 2.02–10.32% and 2.48–17.31%, respectively, compared with systems that use only acoustic signals or medical records. The proposed algorithm also provides higher accuracy and UAR than traditional feature-based and model-based combination methods.
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.
The design and engineering of the size and shapes of photoactive building blocks enable the fabrication of functional nanocrystals, especially for applications in light harvesting, photocatalytic synthesis, water splitting, and photodegradation. Synthesis of such nanocrystals has been demonstrated recently through noncovalent interactions such as π–π stacking and ligand coordination using optically active porphyrin as a functional building block. Depending on the kinetic conditions, the resulting nanocrystals exhibit well-defined one- to three-dimensional shapes such as spheres, nanowires, and nano-octahedra. These well-defined porphyrin nanocrystals show interesting size- and shape-dependent photocatalytic activity. This article reviews the synthesis and formation of porphyrin nanocrystals with controlled size and shape. Important photocatalytic processes such as photodegradation of organic pollutants, photocatalytic water splitting and hydrogen production, and photosynthesis of metallic fuel-cell catalysts are highlighted. Insights on size- and shape-dependent properties are discussed.
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.
In this study, we investigate a new simple scheme using a planar undulator (PU) together with a properly dispersed electron beam (
beam) with a large energy spread (
) to enhance the free-electron laser (FEL) gain. For a dispersed
beam in a PU, the resonant condition is satisfied for the center electrons, while the frequency detuning increases for the off-center electrons, inhibiting the growth of the radiation. The PU can act as a filter for selecting the electrons near the beam center to achieve the radiation. Although only the center electrons contribute, the radiation can be enhanced significantly owing to the high-peak current of the beam. Theoretical analysis and simulation results indicate that this method can be used for the improvement of the radiation performance, which has great significance for short-wavelength FEL applications.
We previously reported four heterozygous missense mutations of MYH7, KCNQ1, MYLK2, and TMEM70 in a single three-generation Chinese family with dual Long QT and hypertrophic cardiomyopathy phenotypes for the first time. However, the clinical course among the family members was various, and the potential myocardial dysfunction has not been investigated.
The objective of this study was to investigate the echocardiographic and electrocardiographic characteristics in a genetic positive Chinese family with hypertrophic cardiomyopathy and further to explore the association between myocardial dysfunction and electric activity, and the identified mutations.
A comprehensive echocardiogram – standard two-dimensional Doppler echocardiography and three-dimensional speckle tracking echocardiography – and electrocardiogram were obtained for members in this family.
As previously reported, four missense mutations – MYH7-H1717Q, KCNQ1-R190W, MYLK2-K324E, and TMEM70-I147T – were identified in this family. The MYH7-H1717Q mutation carriers had significantly increased left ventricular mass indices, elevated E/e’ ratio, deteriorated global longitudinal stain, but enhanced global circumferential and radial strain compared with those in non-mutation patients (all p<0.05). The KCNQ1-R190W carriers showed significantly prolonged QTc intervals, and the MYLK2-K324E mutation carriers showed inverted T-waves (both p<0.05). However, the TMEM70-I147T mutation carriers had similar echocardiography and electrocardiographic data as non-mutation patients.
Three of the identified four mutations had potential pathogenic effects in this family: MYH7-H1717Q was associated with increased left ventricular thickness, elevated left ventricular filling pressure, and altered myocardial deformation; KCNQ1-R190W and MYLK2-K324E mutations were correlated with electrocardiographic abnormalities reflected in long QT phenotype and inverted T-waves, respectively.
Biomimicry is a desirable quality of tissue engineering scaffolds. While most of the scaffolds reported in the literature contain a single pore size or porosity, the native biological tissues such as cartilage and skin have a layered architecture with zone-specific pore size and mechanical properties. Thus, there is a need for functionally graded scaffolds (FGS). EHD-jet 3D printing is a high-resolution process and a variety of polymer solutions can be processed into 3D porous scaffolds at ease, overcoming the limitations of other 3D printing methods (SLS, stereolithography, and FDM) in terms of resolution and limited material choice. In this paper, a novel proof of concept study on fabrication of porous polycaprolactone-based FGS by using EHD-jet 3D printing technology is presented. Organomorphic scaffolds, multiculture systems, interfacial tissue engineering, and in vitro cancer metastasis models are some of the futuristic applications of these polymeric FGS.
Bipolar disorder (BD) has been associated with altered brain structural and functional connectivity. However, little is known regarding alterations of the structural brain connectome in BD. The present study aimed to use diffusion-tensor imaging (DTI) and graph theory approaches to investigate the rich club organization and white matter structural connectome in BD.
Forty-two patients with unmedicated BD depression and 59 age-, sex- and handedness-matched healthy control participants underwent DTI. The whole-brain structural connectome was constructed by a deterministic fiber tracking approach. Graph theory analysis was used to examine the group-specific global and nodal topological properties, and rich club organizations, and then nonparametric permutation tests were used for group comparisons of network parameters.
Compared with healthy control participants, the patients with BD showed abnormal global properties, including increased characteristic path length, and decreased global efficiency and local efficiency. Locally, the patients with BD showed abnormal nodal parameters (nodal strength, nodal efficiency, and nodal betweenness) predominantly in the parietal, orbitofrontal, occipital, and cerebellar regions. Moreover, the patients with BD showed decreased rich club and feeder connectivity density.
Our results may reflect the disrupted white matter topological organization in the whole-brain, and abnormal regional connectivity supporting cognitive and affective functioning in depressed BD, which, in part, be due to impaired rich club connectivity.
Previous cross-lagged studies on depression and memory impairment among the elderly have revealed conflicting findings relating to the direction of influence between depression and memory impairment. The current study aims to clarify this direction of influence by examining the cross-lagged relationships between memory impairment and depression in an Asian sample of elderly community dwellers, as well as synthesizing previous relevant cross-lagged findings via a meta-analysis.
A total of 160 participants (Mage = 68.14, s.d. = 5.34) were assessed across two time points (average of 1.9 years apart) on measures of memory and depressive symptoms. The data were then fitted to a structural equation model to examine two cross-lagged effects (i.e. depressive symptoms→memory; memory→depressive symptoms). A total of 14 effect-sizes for each of the two cross-lagged directions were extracted from six studies (including the present; total N = 8324). These effects were then meta-analyzed using a three-level mixed effects model.
In the current sample, lower memory ability at baseline was associated with worse depressive symptoms levels at follow-up, after controlling for baseline depressive symptoms. However, the reverse effect was not significant; baseline depressive symptoms did not predict subsequent memory ability after controlling for baseline memory. The results of the meta-analysis revealed the same pattern of relationship between memory and depressive symptoms.
These results provide robust evidence that the relationship between memory impairment and depressive symptoms is unidirectional; memory impairment predicts subsequent depressive symptoms but not vice-versa. The implications of these findings are discussed
This research was designed for the first time to investigate the photocatalytic activities of MoO3/g-C3N4 composite in converting CO2 to fuels under simulated sunlight irradiation. The composite was synthesized using a simple impregnation-heating method and MoO3 nanoparticles was in situ decorated on the g-C3N4 sheet. Characterization results indicated that the introduction of MoO3 nanoparticles into g-C3N4 fabricated a direct Z-scheme heterojunction structure. The effective interfacial charge-transfer across the heterojunction significantly promoted the separation efficiency of charge carriers. The optimal CO2 conversion rate of the composite reached 25.6 μmol/(h gcat), which was 2.7 times higher than that of g-C3N4. Additionally, the synthesized MoO3/g-C3N4 also presented excellent photoactivity in RhB degradation under visible-light irradiation.
We report on the radiative transfer process and optical properties of sea ice in the thermal infrared (TIR) band, presenting two new linear kernel driver models (Relative Emissivity Distribution Function, REDF) that describe TIR emission characteristics of smooth and rough ice. In order to test the models and determine the necessary coefficients, in situ measurements from the Bohai Sea were carried out during the 2011/12 and 2012/13 boreal winters. The results show that the relative emissivity of smooth sea ice decreases along with increasing viewing zenith angle, and the shape of the relative emissivity curve is similar to that of an ideal plane. Affected by parameters such as roughness and surface temperature distribution, the anisotropy of relative emissivity of sea ice with a high degree of roughness is stronger relative to the cosine emitter. The model coefficients were also obtained using a robust regression method based on the measured data. The presented models are more practical than the numerical radiative transfer model and can be used for multi-angular TIR remote sensing.
The prevalence of CHD has been well described worldwide except in Tibet. This study aimed to illustrate the prevalence and composition of CHD in Tibetan children according to altitude.
Methods and results
In the first part, we prospectively recruited 7088 unselected Tibetan children (4–17 years) from south-west Tibet. The total prevalence of CHD increased from 4.6/1000 below 4200 m to 13.4/1000 above 4700 m, with a female-to-male ratio of 1.3:3.1. The total prevalence and female prevalence of patent ductus arteriosus increased more than 10-fold. Females living above 4700 m had exceptionally high prevalence of patent ductus arteriosus (14.9/1000). The prevalence of atrial septal defect was comparable among different altitudes (3.3–3.8/1000). The prevalence of ventricular septal defect was 1.3/1000 below 4700 m, and no cases were found above this altitude. In the second part, we retrospectively reviewed the clinical data of 383 CHD children in Tibet and 73 children at lower altitudes. The percentage of isolated ventricular septal defect decreased from 54.8 to 3.1%, and the percentage of isolated patent ductus arteriosus increased from 8.2 to 68.4% with elevation. Children living below 4200 m (10.4–13.7%) had a larger proportion of complex CHD than those above this altitude (2.0–3.1%). Of the 20 Tibetan children with complex CHD, 14 (70.0%) lived below 4200 m.
A wide variation in CHD prevalence and composition existed in Tibetan children among different altitudes.
The on-site hydrogen supply is a key issue for the commercialization of the fuel cells, which is one of the important ways for realizing a hydrogen-economy society. Composite NaNH2–NaBH4 is regarded as a promising high-capacity hydrogen storage material. In this paper, the composite NaNH2–NaBH4 (2/1) was synthesized via a solid-state ball milling method. To improve the hydrogen generation kinetics, a multiplex metal boride Mg–Co–B was selected as the catalyst. It was found that Na3BN2 and metal Na were byproducts in the thermal decomposed sample by X-ray diffraction analysis. Thermogravimetry and differential thermal analysis indicated that the main decomposition stages of the catalyst promoted NaNH2–NaBH4 material were split into three stages. The activation energy of the Mg–Co–B promoted NaNH2–NaBH4 (2/1) material below 300 °C was 76.4 KJ/mol, which is only 47.9% of that of the pristine NaNH2–NaBH4 (2/1), and implying much better hydrogen generation kinetics.
Based on 15 diffusion couples located in face centered cubic single-phase region of ternary Ni–Al–Mo system, high-throughput determination of composition-dependent interdiffusivity matrices at 1273, 1373, and 1473 K was performed by using the recently developed numerical inverse method. The determined main interdiffusivities over the investigated composition and temperature ranges are all positive, and
is generally larger than
generally increases with concentration of Al, while
increases with concentrations of both Al and Mo. In contrast, the cross interdiffusivities can be either positive or negative. Average relative errors of
were evaluated to be 2.4, 5.1, 16.1, and 1.7% using error propagation. Furthermore, our prediction of composition profiles and interdiffusion fluxes based on evaluated interdiffusivity matrices agrees quite well with measured data. Traditional Matano–Kirkaldy method was also applied to further verify the reliability of obtained interdiffusivities. Besides, three-dimensional planes of activation energies of main interdiffusivities were also evaluated using the Arrhenius equation.
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.
We aimed to clarify whether invasive dental treatment is associated with increased risk of prosthetic joint infection (PJI) and whether prophylactic antibiotics may lower the infection risk remain unclear.
Retrospective cohort study.
All Taiwanese residents (N=255,568) who underwent total knee or hip arthroplasty between January 1, 1997, and November 30, 2009, were screened.
The dental cohort consisted of 57,066 patients who received dental treatment and were individually matched 1:1 with the nondental cohort by age, sex, propensity score, and index date. The dental cohort was further divided by the use or nonuse of prophylactic antibiotics. The antibiotic and nonantibiotic subcohorts comprised 6,513 matched pairs.
PJI occurred in 328 patients (0.57%) in the dental subcohort and 348 patients (0.61%) in the nondental subcohort, with no between-cohort difference in the 1-year cumulative incidence (0.6% in both, P=.3). Multivariate-adjusted Cox regression revealed no association between dental procedures and PJI. Furthermore, PJI occurred in 13 patients (0.2%) in the antibiotic subcohort and 12 patients (0.18%) in the nonantibiotic subcohorts (P=.8). Multivariate-adjusted analyses confirmed that there was no association between the incidence of PJI and prophylactic antibiotics.
The risk of PJI is not increased following dental procedure in patients with hip or knee replacement and is unaffected by antibiotic prophylaxis.