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.

To verify whether a graph is suitable for describing driver behaviour performance under the effects of navigation information, this study applies two types of prompt messages: simple and detailed. The simple messages contain only direction instructions, while the detailed messages contain distance, direction, road and lane instructions. A driving simulation experiment was designed to collect the empirical data. Two vehicle operating indicators (velocity and lateral offset), and two driver manoeuvre indicators (accelerator power and steering wheel angle) were selected, and T-test was used to compare the differences of behavioural performance. Driving behaviour graphs were constructed for the two message conditions; their characteristics and similarities were further analysed. Finally, the results of T-test of behavioural performance and similarity results of the driving behaviour graphs were compared. Results indicated that the two different types of prompt messages were associated with significant differences in driving behaviours, which implies that it is feasible to describe the characteristics of driving behaviours guided by navigation information using such graphs. This study provides a new method for systematically exploring the mechanisms affecting drivers’ response to navigation information, and presents a new perspective for the optimisation of navigation information.

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 rate of hyperglycaemia in people around the world is increasing at an alarming rate at present, and innovative methods of alleviating hyperglycaemia are needed. The effects of Jerusalem artichoke inulin on hyperglycaemia, liver-related genes and the intestinal microbiota in mice fed a high-fat diet (HFD) and treated with streptozotocin (STZ) to induce hyperglycaemia were investigated. Inulin-treated hyperglycaemic mice had decreased average daily food consumption, body weight, average daily water consumption and relative liver weight and blood concentrations of TAG, total cholesterol, HDL-cholesterol and fasting blood glucose. Liver-related gene expressions in hyperglycaemic (HFD-fed and STZ-treated) compared with control mice showed eighty-four differentially expressed genes (forty-nine up-regulated and thirty-five down-regulated). In contrast, hyperglycaemic mice treated with inulin had twenty-two differentially expressed genes compared with control ones. Using Illumina high-throughput sequencing technology, the rarefaction and the rank abundance curves as well as the α diversity indices showed the treatment-induced differences in bacterial diversity in intestine. The linear discriminant analysis of effect size showed that the inulin treatment improved intestinal microbiota; in particular, it significantly increased the number of Bacteroides in the intestine of mice. In conclusion, inulin is potentially an effective functional food for the prevention and/or treatment of hyperglycaemia.

Coatings with low friction coefficient and excellent anti-wear and anticorrosion performances are of great interest for fundamental research and practical applications. In the present study, Cobalt–nickel–phosphorus/graphene oxide (Co–Ni–P/GO) composite coating is prepared by a pulse electrodeposition method. Effect of the embedded GO sheets on the microstructures, microhardness, and electrochemical and tribological behaviors of the Co–Ni–P/GO composite coating are researched in detail. The results reveal that the co-deposition of GO sheets significantly improves the microhardness of the as-prepared Co–Ni–P/GO composite coating and changes the morphology of the Co–Ni–P coating from hemispheric structure to nodule structure with smaller globular particles for the Co–Ni–P/GO composite coating. In addition, friction and wear tests show that the incorporation of GO sheets endows the Co–Ni–P/GO composite coating with remarkable friction reduction and improved wear resistance. Electrochemical corrosion tests demonstrate that the Co–Ni–P/GO composite coating possesses better corrosion resistance than the Co–Ni–P coating.

The container liner shipping industry has stepped into an era of international strategic alliances. Important to these liner alliances is the sharing and allocation of container slots between its member carriers. This paper optimises planning of container ship capacity sharing and co-allocation under a co-charting agreement. First, we explain the concept of this business agreement and its implications on maritime operations. Then, we identify key influencing factors that may affect the decisions of cooperative slot co-allocation. The slot co-allocation problem is modelled as an Integer Programming problem and solved using data from two routes between the United States and Asia. The model determines the optimal slot co-allocation strategies between shipping alliance carriers along allied shipping routes. Computational results indicate that the proposed method is effective in obtaining optimal, cooperative slot sharing strategies that can maximise the total system revenue.

Influence of corrosion/fatigue factors on the fatigue life of 7B04-T6 aluminum alloys were studied in this paper. Different kinds of alternating corrosion-fatigue tests were carried out. Three factors influencing fatigue life were investigated: pre-corrosion time, corrosion/fatigue alternation frequency, and specimen’s size. The results show that: with the extension of pre-corrosion time, fatigue lives decreased; although the total corrosion time was the same (192 h), as the corrosion/fatigue alternation frequency increased, the total fatigue lives increased. The total fatigue lives of specimens subjected to two, four, and six corrosion/fatigue cycles (n = 2, 4, 6), in which specimens underwent pre-corrosion for 96 h per cycle (n = 2), 48 h per cycle (n = 4), and 32 h per cycle (n = 6), respectively, was measured. It was found that the fatigue lives increased by 56.4, 84.4, 136%, as the number of cycles increased, compared to tests in which no alternation took place (192 h of continuous corrosion). When exposed to the same corrosion times, different sized specimens demonstrated different fatigue lives. The fatigue lives of small specimens were shorter than the larger specimens. These results are all due to the specific properties of corrosion/fatigue factors.

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.

We present the results of a mixed-space approach, based on first-principles calculations, to investigate phonon dispersions and thermal properties of Mg2Si and Mg2Sn, including the bulk modulus, Grüneisen parameter, heat capacity, and Debye temperature. It is shown that good agreements are obtained between the calculated results and available experimental data for both phonon dispersions and thermal properties. The phonon dispersions are accurately calculated compared with experimental data due to the high-quality description of LO–TO splitting and transverse acoustic branches along the Γ-K-X symmetry line. We also calculate the heat capacity CP and Debye temperature of Mg2Si1−xSnx alloys (x = 0.375, 0.5, 0.625, 0.875). The CP values at high temperature range from 0.5 to 0.7 J/g/K and ΘD values at room temperature from 332 to 384 K as the Sn content decreases from 0.875 to 0.375.

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.

The microstructure and thermoelectric properties of InSb–NiSb composite system are investigated. NiSb, ranging from micro- to nanoscale, is introduced as a nonsoluble second phase in the InSb matrix by using the water quenching method. The morphology of the second phase is adjusted by varying the composition from hypoeutectic to hypereutectic alloys. The eutectic composite with a semiconducting InSb matrix and a metallic NiSb fiber on the order of 100-nm diameter is obtained. Melt spinning (MS) is applied to the eutectic composition to change the NiSb dispersion phase to around 200-nm diameter sphere. Transport properties, including Seebeck coefficient, resistivity, Hall coefficient, and thermal conductivity, are measured from 80 to 630 K. Compared to the water quenched (WQ) eutectic sample, the MS process results in a slight increase in the carrier concentration but a remarkable reduction in the mobility and thermal conductivity. Compared to the InSb matrix, ZT of the samples with the NiSb second phase is lower. For the eutectic samples, ZT is significantly reduced after the MS process because of the loss in mobility. ZT of the WQ InSb matrix is the highest in all the samples, ∼0.5 at 600 K.

Magnetic cobalt ferrite nanoparticles provide a pathway towards nanocomposites, due to the ability to fabricate particle-matrix thin films in the submicron range. In this work flexible particulate 0-3 type thin-films, composed of magnetic CoFe2O4 particles (8-18 nm) and ferroelectric poly(vinylidene fluoride-co-hexafluoropropene) (P(VDF-HFP)) polymer, have been fabricated via multiple spin-coating. The thickness of the thin-films was controlled in the range of 500 nm to 1.2 μm, with magnetic particles dispersively embedded in the polymer matrix. Structural information was analyzed by TEM, XRD, HRTEM and SEM. The dielectric and magnetic properties of the cobalt ferrite/copolymer thin films are systematically investigated. The nanocomposite thin films exhibit composition-dependent effective permittivity and loss tangent, as well as temperature and composition-dependent specific saturation magnetization (Ms). The coercivity (Hc) was not affected by the composite’s composition. These films have great potential in smart magnetic devices and biomagnetic applications.

Black persimmon in the literature. The persimmon (Diospyros kaki L.) is a deciduous fruit tree originating in China. One type consisting of a group of similar cultivars is the black persimmon, which is a precious germplasm resource of China. Black persimmon is mainly distributed in the south of the Taihang Mountains in northern China. Black persimmon is astringent, though this astringency can now be removed easily via normal maturity of the fruit. The skin of the fruit is black and the flesh has abundant nutritional value, with vitamin C and carotene. Information given by a black persimmon orchard. A trial on black persimmon was carried out from 2003 to 2009 in Zhengzhou, Henan province, China. Plant growth, yields and phenological characteristics were studied. The fruit has a thick skin which assists in storage and transportation; it has excellent flavor and quality, making the fruit highly valued by producers, marketers and consumers. Key cultivation techniques. Practices to achieve high quality are reviewed such as the proper plant environment, tree planting and pruning, the soil management, the wintering and protection of young trees, and pest control.

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.

One-dimensional (1D) nano-materials have attracted a plenty of attention due to their novel structures and properties. Our group has carried out researches on synthesis, structure and property of 1D nano-materials, which are introduced in this paper. First, size effects on the crystal structure of Ag nanowires and on Young's modulus in [0001] oriented ZnO nanowires, respectively, have been revealed and modeled. The former is concerning the systemic energy of an individual Ag nanowire. The latter is caused by the surface stiffening effect arising from surface relaxation induced bond length contractions in the ZnO nanowires. Second, structures of 1D helical nano-materials including SWCNT (single-walled carbon nanotube), B-DNA and MWCNT (mutli-walled carbon nanotube) have been studied. It is shown that there is strong orientation dependence of diffraction intensities from SWCNT and B-DNA, which can even result in certain layer lines missing in their diffraction patterns. Also, it is demonstrated that high-resolution transmission electron microscope (TEM) images of sidewall regions of MWCNTs are not structural ones and from the interference of the {0002} and the {1011} diffraction waves. Third, arrays of four types of 1D heterojunctions have been synthesized. Among these 1D heterojunctions, the interfacial structures of the Ni/MWCNT/a-CNT(amorphous carbon nanotube) heterojunctions show that multiple outer walls in the MWCNTs can simultaneously participate in electrical transport. The electrical properties of the Ni/MWCNT/a-CNT and the Ag/a-CNT heterojunctions have been measured. As a result, it is found that the contacts between the Ag nanowires and the a-CNTs are ohmic ones with universal significance, and that each Ni/MWCNT/ a-CNT contains two diodes connected in series face-to-face. Moreover, most of the diodes have the most nearly ideal characteristics of Schottky contacts, indicated by quantitative analysis with the thermionic emission theory. Last, our group has developed a novel technique for rapidly producing large-area highly-oriented Si nanowire arrays on Si wafers by scratching the Si surface with metal nanoparticles near room temperature in HF solution. By this method, Si nanowires with desirable axial crystallographic directions, desirable doping characteristics and remarkable antireflection property can be readily obtained. The Si nanowire arrays have the potential applicability as an antireflective layer for photovoltaic devices and optical detectors. Furthermore, a combination of this method and the nanosphere lithography has been developed to fabricate large-scale Si and Si1−xGex quantum dot arrays with controllable height, diameter and center-to-center distance.

The architectural design and surface properties of scaffolds are important aspects in tissue engineering. The porous scaffolds accommodate cells and guide their growth, while the surface nature of the scaffolds can directly affect cell attachment, proliferation, and ultimately neo tissue regeneration. In this work, a highly porous poly(L-lactic acid) (PLLA) scaffold with nano-fibrous pore wall architecture has been fabricated by mimicking the structure of natural collagen using a novel thermally induced phase separation method developed in our group. A universally effective surface modification method was developed, and gelatin was successfully grafted onto the surface of nano-fibrous PLLA scaffolds by entrapment procedure. The surface composition, morphology, and properties were examined using ATR-FTIR, XPS and SEM. The surface coverage of gelatin on the PLLA surface was as high as 39.4%. MC3T3-E1 osteoprogenitor cells were cultured for 6 weeks in solid-walled PLLA scaffolds, nano-fibrous PLLA scaffolds, and surface-modified nano-fibrous PLLA scaffolds, respectively. The osteoblasts proliferated in all three types of scaffolds, but the cell numbers were always significantly higher in the surface-modified nano-fibrous scaffolds than in the other two types of scaffolds, and the cell numbers in nano-fibrous scaffolds were higher than that in the solid-walled scaffolds. These results demonstrate that the surface-modified nano-fibrous architecture could serve as a superior scaffold for tissue engineering.

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.