This paper retrospectively analysed the prevalence of macrolide-resistant Mycoplasma pneumoniae (MRMP) in some parts of China. Between January 2013 and December 2019, we collected 4,145 respiratory samples, including pharyngeal swabs and alveolar lavage fluid. The highest PCR-positive rate of M. pneumoniae was 74.5% in Beijing, the highest resistance rate was 100% in Shanghai, and Gansu was the lowest with 20%. The highest PCR-positive rate of M. pneumoniae was 74.5% in 2013, and the highest MRMP was 97.4% in 2019; the PCR-positive rate of M. pneumoniae for adults in Beijing was 17.9% and the MRMP was 10.48%. Among the children diagnosed with community-acquired pneumonia (CAP), the PCR-positive and macrolide-resistant rates of M. pneumoniae were both higher in the severe ones. A2063G in domain V of 23S rRNA was the major macrolide-resistant mutation, accounting for more than 90%. The MIC values of all MRMP to erythromycin and azithromycin were ≥ 64 μg/ml, and the MICs of tetracycline and levofloxacin were ≤ 0.5 μg/ml and ≤ 1 μg/ml, respectively. The macrolide resistance varied in different regions and years. Among inpatients, the macrolide-resistant rate was higher in severe pneumonia. A2063G was the common mutation, and we found no resistance to tetracycline and levofloxacin.

This study aims to understand the epidemiological characteristics of SARS-CoV-2 infection in the paediatric population during the outbreak of the Omicron variant in Shanghai. We retrospectively analysed the population-based epidemiological characteristics and clinical outcome of SARS-CoV-2 Omicron variant infection in children in Minhang District, Shanghai, based on the citywide surveillance system during the outbreak period in 2022 (March to May). During this time, a total of 63,969 cases of SARS-CoV-2 infection were notified in Minhang District, out of which 4,652 (7.3%) were children and adolescents <18 years. The incidence rate of SARS-CoV-2 infections in children was 153 per 10,000. Of all paediatric cases, 50% reported to be clinically symptomatic within 1–3 days after PCR confirmation by parents or themselves, with 36.3% and 18.9% of paediatric cases reporting fever and cough. Also, 58.4% of paediatric cases had received at least one dose of the COVID-19 vaccine and 52.1% had received two doses of the COVID-19 vaccination. Our findings are informative for the implementation of appropriate measures to protect children from the threat of SARS-CoV-2 infection.

Dietary l-carnitine (LC) is a nutritional factor that reduces liver lipid content. However, whether dietary LC can improve lipid metabolism via simultaneous activation of mitochondrial fatty acid (FA) β-oxidation and suppression of endoplasmic reticulum (ER) stress is still unknown. Large yellow croaker were fed with a high-fat diet (HFD) supplemented with dietary LC at 0, 1·2 or 2·4 ‰ for 10 weeks. The results indicated that a HFD supplemented with LC reduced the liver total lipid and TAG content and improved serum lipid profiles. LC supplementation administered to this fish increased the liver antioxidant capacity by decreasing serum and liver malondialdehyde levels and enhancing the liver antioxidant capacity, which then relieved the liver damage. Dietary LC increased the ATP dynamic process and mitochondrial number, decreased mitochondrial DNA damage and enhanced the protein expression of mitochondrial β-oxidation, biogenesis and mitophagy. Furthermore, dietary LC supplementation increased the expression of genes and proteins related to peroxisomal β-oxidation and biogenesis. Interestingly, feeding fish with LC-enriched diets decreased the protein levels indicative of ER stress, such as glucose-regulated protein 78, p-eukaryotic translational initiation factor 2a and activating transcription factor 6. Dietary LC supplementation downregulated mRNA expression relative to FA synthesis, reduced liver lipid and relieved liver damage through regulating β-oxidation and biogenesis of mitochondria and peroxisomes, as well as the ER stress pathway in fish fed with HFD. The present study provides the first evidence that dietary LC can improve lipid metabolism via simultaneously promoting FA β-oxidation capability and suppressing the ER stress pathway in fish.

It is well known that the pressure fluctuations on both sides of a cylinder and those in its oscillating near-wake region are both sound sources at low Reynolds and Mach numbers. However, assessment of the propagating capacity and quantification of the radiating versus non-radiating components of these two sound sources are not currently available for this important benchmark aeroacoustic problem. Here, we isolate the radiating acoustic sound sources from the non-radiating hydrodynamic pseudo-sounds by applying the wavelet decomposition technique of Mancinelli et al. (J. Fluid Mech., vol. 813, 2017), previously used in subsonic jet-noise experiments, to decompose the cylinder near-field pressure fluctuations obtained from our direct numerical simulations. Rigorous independence and convergence analyses of the wavelet decomposition procedure are performed. It is found that the radiating acoustic component strongly dominates over the non-radiating hydrodynamic component at near-field locations above and upstream of the cylinder. In the oscillating near-wake region, the hydrodynamic component dominates over the acoustic component at most frequencies, except at the vortex shedding frequency where they exhibit comparable strengths. Furthermore, within the oscillating near-wake region, the overall sound pressure level associated with the hydrodynamic pressure fluctuations exceeds that associated with the acoustic pressure fluctuations. Away from the oscillating near-wake region, the hydrodynamic pressure fluctuations decrease dramatically while the acoustic counterparts decay slowly, demonstrating that the hydrodynamic pressure fluctuation does not propagate, and that the acoustic pressure fluctuation is the only component to propagate to the far field.

The mortality of coronavirus disease 2019 (COVID-19) differs between countries and regions. This study aimed to clarify the clinical characteristics of imported and second-generation cases in Shaanxi. This study included 134 COVID-19 cases in Shaanxi outside Wuhan. Clinical data were compared between severe and non-severe cases. We further profiled the dynamic laboratory findings of some patients. In total, 34.3% of the 134 patients were severe cases, 11.2% had complications. As of 7 March 2020, 91.8% patients were discharged and one patient (0.7%) died. Age, lymphocyte count, C-reactive protein, erythrocyte sedimentation rate, direct bilirubin, lactate dehydrogenase and hydroxybutyrate dehydrogenase showed difference between severe and no-severe cases (all P < 0.05). Baseline lymphocyte count was higher in survived patients than in non-survivor case, and it increased as the condition improved, but declined sharply when death occurred. The interleukin-6 (IL-6) level displayed a downtrend in survivors, but rose very high in the death case. Pulmonary fibrosis was found on later chest computed tomography images in 51.5% of the pneumonia cases. Imported and second-generation cases outside Wuhan had a better prognosis than initial cases in Wuhan. Lymphocyte count and IL-6 level could be used for evaluating prognosis. Pulmonary fibrosis as the sequelae of COVID-19 should be taken into account.

To study the interface characteristics between substrates and homoepitaxially grown single crystalline diamond layers, the high-pressure/high-temperature Ib diamond seeds with homoepitaxial diamond layers were annealed by low-pressure/high-temperature treatment in a hydrogen environment. The stress evolution and related impurity transformation near the interface were characterized by Raman spectroscopy, photoluminescence, and micro-infrared spectroscopy before and after annealing. It is found that the stress is the smallest in a 100 μm wide zone near the interface, accompanying with the similar change in substitutional nitrogen (Ns) concentration. After annealing at 1050 °C, 1250 °C, and 1450 °C, the local compressive stress is released gradually with temperature change. It is decreased by 1.03 GPa in maximum after annealing at 1450 °C. The concentration of nitrogen–vacancy (NV) complexes in the chemical vapor deposition (CVD) layer is dramatically reduced at 1450 °C. The value of ${{I_{{\rm{NV}}^ \hbox- } } \mathord{\left/ {\vphantom {{I_{{\rm{NV}}^ - } } {I_{{\rm{diamond}}} }}} \right. \kern-\nulldelimiterspace} {I_{{\rm{diamond}}} }}$ decreases much more than ${{I_{{\rm{NV}}^0 } } \mathord{\left/ {\vphantom {{I_{{\rm{NV}}^0 } } {I_{{\rm{diamond}}} }}} \right. \kern-\nulldelimiterspace} {I_{{\rm{diamond}}} }}$ in the CVD layer, which is due to the lower stability of NV− compared with NV0 at high temperature.

The aim of this research is to investigate elevation changes in the Antarctic ice sheet by comparing two digital elevation models (DEMs) derived from satellite altimetry data covering the period 1994–2004. Data collected by ERS-1/2 satellite radar altimetry and by NASA GLAS/ICESat laser altimetry were used. After preprocessing and resampling at the same spatial resolution, both DEMs were compared in a pointwise fashion and elevation differences computed, which consisted of three main components: (1) actual elevation change, (2) errors in the original data sources and (3) interpolation errors that arose during generation of the DEMs. The objectives of the research were to analyze errors, attempt to mitigate systematic effects when possible, and draw some conclusions about the limitations of using DEM products for computing ice-sheet elevation change at local and continental scales. A linear correlation between errors in elevation differences and surface slope was found in the slope range [0°, 0.4°]. This trend was interpreted as residual slope-induced systematic error and compensated for. Finally, an elevation difference map of the Antarctic ice sheet was generated. Analysis of the derived elevation changes at the drainage basin was also made. Results are compared with the results of previous studies.

We study the effects of Dy, Nb, and Ga additions on the microstructure and magnetic properties of Nd2Fe14B/α-Fe nanocomposites. Dy, Nb, and Ga additions inhibit the growth of the soft magnetic α-Fe phase. Dy and Nb additions are able to refine the microstructure, whereas Ga addition plays only a minor role in prohibiting crystal growth. The magnetic properties are sensitive to Dy, Nb, and Ga additions. The Dy-containing alloy enhances the intrinsic coercivity of 872 kA/m because Dy partially replaces Nd, forming (Nd, Dy)2Fe14B. Nb addition refines the microstructure, and consequently increases the exchange coupling between magnetic grains. The Nd9.5Fe75.4Co5Zr3B6.5Ga0.6 alloy exhibits the highest remanence (0.92 T) due to Ga addition.

Gauged river flow records from China generally span only a few decades, which hampers the detection of long-term, decadal- to centennial-scale cycles and trends in streamflow variability. New and updated tree-ring chronologies help reconstructed the water-year (October–September) streamflow for the Aksu River, which is an important river at the edge of the Taklimakan Desert that drains into the Tarim Basin. The reconstruction dates back to 1692 and has an adjusted r2 of 0.61 (1957–2006). Based on frequency, intensity and duration of droughts and pluvial events, the lowest streamflows occurred in the 1920s. Since then streamflow has continuously increased, and was exceptionally rapidly after the 1960s, until today. The start and end of the 20th century to the present were the highest streamflow periods. The mid-20th century was the longest and driest period over the past 300 yr. The reconstructed streamflow series has a strong positive correlation with the North Atlantic Oscillation Index. Changes in mid-latitude circulation patterns influencing precipitation may have indirectly resulted in streamflow variations along the Aksu River over the past 300 yr. The rapid increase and the exceptional streamflows of the 1960s are likely linked with global warming and mid-latitude atmospheric circulation changes.

We present results of a regional comparative study of surface mass changes from 2004 to 2008 based on Gravity Recovery and Climate Experiment (GRACE), The Ice, Cloud and Land Elevation Satellite (ICESat) and CHINARE observations over the Lambert Glacier/Amery Ice Shelf system (LAS). Estimation of the ICESat mass change rates benefitted from the density measurements along the CHINARE traverse and a spatial density adjustment method for reducing the effect of spatial density variations. In the high-elevation inland region, a positive trend was estimated from both ICESat and GRACE data, which is in line with the CHINARE accumulation measurements. In the coastal region, there were areas with high level accumulations in both ICESat and GRACE trend maps. In many high flow-speed glacier areas, negative mass change rates may be caused by dynamic ice flow discharges that have surpassed the snow accumulation. Overall, the mass change rate estimate in the LAS of 2004–2008 from the GRACE, ICESat and CHINARE data is 5.41 ± 4.59 Gt a−1, indicating a balanced to slightly positive mass trend. Along with other published results, this suggests that a longer-term positive mass trend in the LAS may have slowed in recent years.

The inverse problem considered in this paper is to determine the shape and the impedance of crack from a knowledge of the time-harmonic incident field and the corresponding far field pattern of the scattered waves in two-dimension. The combined single- and double-layer potential is used to approach the scattered waves. As an important feature, this method does not require the solution of u and ∂u/∂v at each iteration. An approximate method is presented and the convergence of this method is proven. Numerical examples are given to show that this method is both accurate and simple to use.

In this work, the improved (G′/G)-expansion method is proposed for constructing more general exact solutions of nonlinear evolution equation with the aid of symbolic computation. In order to illustrate the validity of the method we choose the RLW equation and SRLW equation. As a result, many new and more general exact solutions have been obtained for the equations. We will compare our solutions with those gained by the other authors.

New single-buffer layers of YBiO3 and SmBiO3 have been proposed for YBa2Cu3O7−y (YBCO) and SmBa2Cu3O7−y coated conductors. Highly c-axis oriented YBiO3 and SmBiO3 buffer layers have been deposited on single-crystal LaAlO3 and SrTiO3, respectively, by a low-cost chemical solution deposition method in a temperature range as low as 730 to 800 °C in air. Precursor solution of yttrium nitrate, samarium nitrate, and bismuth nitrate has been deposited using spin coating and heat treated in air in a single stage to yield textured YBiO3 and SmBiO3 buffers. A very dense, smooth, pinhole-free, and crack-free morphology has been observed for both buffers. Dense, homogeneous, and epitaxially grown YBCO film with thickness about 300 nm has been obtained on YBiO3 buffer with onset critical temperature 90 K and Jc (77 K, self-field) over 3 MA/cm2. These results offer an effective alternative to prepare desirable buffer layer(s) for YBCO-coated conductors.

The improved effects of dietary chickpeas on visceral adiposity, dyslipidaemia and insulin resistance were examined. Rats were fed a normal-fat diet (NFD), a high-fat diet (HFD) or a high-fat plus chickpea diet (HFD+CP) for 8 months. The epididymal fat pad weight v. total body weight of rats was higher in the HFD group (0·032 (sd 0·0042) g/g) than in the NFD group (0·015 (sd 0·0064) g/g) and smaller in the HFD+CP group (0·023 (sd 0·0072) g/g) compared with the HFD group (P < 0·05). Chickpea treatment also induced a favourable plasma lipid profile reflecting decreased TAG, LDL-cholesterol (LDL-C) and LDL-C:HDL-cholesterol levels (P < 0·05). HFD-fed rats had higher TAG concentration in muscle and liver, whereas the addition of chickpeas to the HFD drastically lowered TAG concentration (muscle, 39 %; liver, 23 %). The activities of lipoprotein lipase (LPL) in epididymal adipose tissue and hepatic TAG lipase in liver recorded a 40 and 23 % increase respectively in HFD rats compared with those in NFD rats; dietary chickpeas completely normalised the levels. Furthermore, chickpea-treated obese rats also showed a markedly lower leptin and LPL mRNA content in epididymal adipose tissue. An insulin tolerance test, oral glucose tolerance test and insulin-releasing test showed that chickpeas significantly improved insulin resistance, and prevented postprandial hyperglycaemia and hyperinsulinaemia induced by the chronic HFD. The present findings provide a rational basis for the consumption of chickpeas as a functional food ingredient, which may be beneficial for correcting dyslipidaemia and preventing diabetes.

It is very important to study a new method of nondestructive internal microtomography of semiconductors and IC. in this paper, we report some research results that were obtained in resent years using nondestructive internal microtomography (NDIMT) to study semiconductor materials(SM) and microelectronic devices (MD) in SEM. Now we can apply this method to detect the microstructures and defects in the subsurface of SM. The conditions of microstructures and the defects being or not in the subsurface of SM used directly depend on the quality of MD. By attaching a special attachment that was devised based on the NDIMT to SEM we can perform nondestructive internal microtomographic visualization of the subsurface of SM the tested SM may be used latter to produce MD. in this way NDIMT may be used to select good quality SM which can then be used for research and production of MD. The product yield and reliabilities of MD can therefore be improved.

In the paper, we firstly publish a new method of internal micrographic visualization of semiconductor and IC. The quality and reliability of the semiconductor materials (SM) and the integrated circuits (IC) have always been concerned Having a high resolution, high reliable and nondestructive detection method is the key element for their improvements.

Silicon oxide layers are used to provide the electrical insulation in the multi-structured ICs. The IC device surfaces are often protected by silicon oxide and silicon nitride layers. Therefore, these insulation layers also cover any inhomogeneity and defect located within the IC devices. It is necessary to have an examining method to detect those defects that are under the insulation layers without damaging the samples. However, the conventional scanning electron microscope (SEM) cannot be utilized to image and examine the surfaces that are positioned below the insulation layers.

Novel nondestructive and contactless method has been developed in our laboratory to obtain the internal micrograph that crosses the surface of the semiconductor material and the integrated circuit.

The polymerization mechanism of a modified Pechini process was investigated by 87Sr nuclear magnetic resonance spectroscopy for the mixed solution of strontium nitrate, citric acid, and ethylene glycol. The C-ratio (the ratio of citric acid to metal ions in the polymer complex) is suggested to have a strong influence on the quality of the derived film. An analysis of the chemical shift variation, as a function of C-ratio, indicates the presence in the solution of two species: solvated strontium ions and strontium ions bound to the polymer complex, with a stoichiometry of 1:7. A polymeric precursor model based on this stoichiometry is proposed. Through a relaxation rate study of the strontium sites, it was found that the polymerization mechanism is predominantly bimolecular within the concentration region being studied. The equilibrium rate constant for the polymerization was calculated to be 104 s−1. A kinetic study of the fast cation exchange between the two identified strontium sites indicates that the inhomogeneity of the polymeric network leads to film cracking during pyrolysis.