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We present an extension of the classical De Giorgi class, and then we show that functions in this new class are locally bounded and locally H\"older continuous. Some applications are given. As a first application, we give a regularity result for local minimizers $u:\Omega \subset \mathbb R^4 \rightarrow \mathbb R^4$ of a special class of polyconvex functionals with splitting form in four dimensional Euclidean spaces. Under some structural conditions on the energy density, we prove that each component $u^\alpha$ of the local minimizer $u$ belongs to the generalized De Giorgi class, then one can derive that it is locally bounded and locally H\"older continuous. Our result can be applied to polyconvex integrals whose prototype is $$ \int_\Omega \Big(\sum_{\alpha =1}^4 |Du^\alpha|^p + \sum_{\beta =1}^6 |({\rm adj}_2 Du )^\beta | ^q +\sum_{\gamma =1}^4 |({\rm adj}_3 Du )^\gamma | ^r +|\det Du|^s \Big ) \mathrm {d}x $$ with suitable $p,q,r,s\ge 1$. As a second application, we consider a degenerate linear elliptic equation of the form $$ -\mbox {div} (a(x)\nabla u)=-\mbox {div}F, $$ with $0, Comment: 41 pages

The aim of this study was to explore the influence of different intensities of acute aerobic exercise on brain activation in male methamphetamine (MA)-dependent patients during exercise. Twenty MA-dependent patients were divided randomly into two groups participating in 35 min of either moderate- or high-intensity aerobic exercise. Functional near-infrared spectral imaging (fNIRS) was used to detect hemodynamic changes in prefrontal cortex during the main 25-min exercise stage. The results revealed that high-intensity acute aerobic exercise aroused more cerebral oxygenation changes in the prefrontal cortex and left dorsolateral prefrontal cortex during exercise as compared with moderate-intensity exercise. Furthermore, there was a stronger positive connection observed between orbital frontal cortex and left dorsolateral prefrontal cortex in the high-intensity group than in the moderate-intensity group. Together these results suggest that for submaximal exercise intensities, high-intensity exercise may bring more benefits to male MA-dependent patients than moderate-intensity.

Underwater acoustic environment (UAE) prediction is essential for accurately estimating sonar performance and making credible tactical decisions. Modular Ocean Data Assimilation System (MODAS) provides an efficient way to reconstruct real-time three-dimensional ocean sound speed field and has potential use in UAE prediction. However, the effect of MODAS on UAE prediction is not clear, which prevents MODAS from being used in practice. Taking into account that convergence zone (CZ) is a typical feature of deep-sea UAE, this paper studies the effect of MODAS on CZ distance prediction. A method is proposed to describe the accuracy of CZ distance prediction quantitatively. The method takes the CZ distance as a random variable and uses Monte Carlo sampling method to obtain the probability density function (PDF) of CZ distance. The performance of MODAS on CZ distance prediction is numerically simulated in a range-independent and a mesoscale eddy waveguides. It is shown that: (1) In the range-independent waveguide, if the sound speed disturbance of internal waves with respect to the background sound speed profile is less than the RMSE of MODAS, the prediction of CZ distance for local measured sound velocity profile is more accurate. (2) In the mesoscale eddy waveguide, the performance of MODAS is better and the performance improves as the RMSE of MODAS decreases.

Aerostatic bearings are the core parts of ultra-high-speed spindles with maximum running speed greater than 100,000 r/min. In this paper, the influences of herringbone grooves on the performance of aerostatic journal bearings are studied to design spindles with the features of higher precision and higher speed. Parametric studies and sensitivity analyses are executed in terms of the improved finite element method, which is specially developed to solve the compressible Reynolds equation for herringbone grooved air bearings. The calculated results indicate that herringbone grooves significantly improve the performance of aerostatic journal bearings under the conditions of ultra-high speeds and low supply pressures. Groove parameters are nonlinear dependent, and groove depth and length are the dominant influential factors for the load capacity at speed of 200,000 r/min. Experiments are designed and conducted to verify the improved finite element method, which show that the improved finite element method can be used to analyze the influences of herringbone grooves on aerostatic journal bearings and also manifest that suitable herringbone groove geometrical parameters can obviously decrease spindle radial runouts at ultra-high speeds.

A novel genus Parametarhizium with two new entomopathogenic species, Parametarhizium changbaiense and Parametarhizium hingganense, was introduced based on their morphological characteristics and a multigene phylogenetic analysis, which were isolated from the forest litters collected in Northeast China. To infer their phylogenetic relationships, a six-gene dataset consisting of DNA fragments of [nuclear small subunit rDNA (SSU) + LSU + TUB + TEF + RPB1 + RPB2] was used for phylogenetic analysis, including 105 related fungi. The new genus Parametarhizium formed a monophyletic clade basal to Metarhizium and its related genera (formerly Metarhizium sensu lato). Parametarhizium can be morphologically distinguished from related genera by the combination of the following characteristics: formation of white to yellow colonies on different media, candelabrum-like arrangement of cylindrical or obpyriform phialides, and small subglobose to ellipsoidal conidia. Both P. hingganense and P. changbaiense exhibited anti-insect activities against three farmland pests Monolepta hieroglyphica, Callosobruchus chinensis, and Rhopalosiphum maidis. This is the first report of entomopathogenic fungi exhibiting the anti-insect activity against Mo. hieroglyphica.

Stimuli-sensitive nanocomposites have received special attention because of their potential applications in various fields. In this work, we report a novel thermo-responsive photoluminescent silver clusters/hydrogel nanocomposite with red emission, as a probe for highly sensitive and selective detection of Cr(VI) in aqueous solutions. The hydrogel nanocomposites integrate the advantages of p(NIPAM-co-AAc) hydrogel submicron particles and Ag clusters: the p(NIPAM-co-AAc) hydrogel submicron particles can act as templates for Ag nanoclusters and exhibit thermo-responsive properties. In addition, Ag nanoclusters endow excellent photoluminescent properties to our nanocomposites, resulting in photoluminescent sensors. As a result, we obtained novel thermo-responsive Ag clusters/p(NIPAM-co-AAc) hydrogel nanocomposites through photoreduction process. The photoluminescence (PL) intensity of as-prepared nanocomposites exhibited a linear and reversible response from 2 to 85 °C and displayed a high PL quenching for the sensitive and selective detection of Cr(VI), rather than Cr(III). The limit of detection could reach as low as 1 ppb, which indicates that it is an ideal sensor tool for environmental monitoring, laboratory detections and various other applications.

Flotation has been proven to successfully remove most polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) and carbon constituents from hospital solid waste incinerator (HSWI) fly ash. The resultant froths contain large quantities of carbon constituents that can reburn in the incinerator. In this paper, the reburning behavior of froths at temperatures from 800°C to 1200°C was compared with that of HSWI fly ash. Results showed that the destruction efficiency of PCDD/Fs was higher in the froths than in the fly ash at the same reburning temperature. The destruction efficiencies of PCDD/Fs in the froths exceeded 98% at temperatures higher than 1000°C. The volatilization ratio of Pb, Zn, and Cu was lower in the froths than in the fly ash. Furthermore, reburning of the froths can achieve energy recovery of the carbon constituents. Therefore, flotation followed by reburning treatment in a combustion chamber could be a suitable process for the detoxification and reutilization of HSWI fly ash.