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Abstract Background To verify the validity of diagnosing initial caries on occlusal surface of permanent posterior teeth by laser fluorescence instrument DIAGNOdent pen. Methods Patients from School of Stomatology in Wuhan University were selected and their posterior teeth were examined using DIAGNOdent pen and the International Caries Detection and Assessment System (ICDAS II) by an experienced dentist. After teeth extraction, histological criteria were used to determine the severity of the lesions. The sensitivity, specificity, accuracy, the area under the curve (AUC), and correlation of DIAGNOdent pen and ICDAS II were analyzed compared with histological criteria. Examiners’ agreement was measured. Results The sensitivity range was 0.440-1 while that of specificity was 0.750–0.994. The accuracy and AUC were above 80% and 0.7 respectively. Consistency of examiners’ kappa values of ICDAS II, DIAGNOdent pen, and histological criteria were ranged from 0.629 to 0.840. Conclusions ICDAS II and DIAGNOdent pen can be effectively used in tandem or independently for the assessment of initial caries.

In this article, we are concerned with the nonlinear Schrödinger equation −Δu+λu=μ∣u∣p−2u+f(u),inR2,-\Delta u+\lambda u=\mu {| u| }^{p-2}u+f\left(u),\hspace{1em}\hspace{0.1em}\text{in}\hspace{0.1em}\hspace{0.33em}{{\mathbb{R}}}^{2}, having prescribed mass ∫R2∣u∣2dx=a2>0,\mathop{\int }\limits_{{{\mathbb{R}}}^{2}}{| u| }^{2}{\rm{d}}x={a}^{2}\gt 0, where λ\lambda arises as a Lagrange multiplier, μ>0\mu \gt 0, p∈(2,4]p\in \left(2,4], and the nonlinearity f∈C1(R,R)f\in {C}^{1}\left({\mathbb{R}},{\mathbb{R}}) behaves like e4πu2{e}^{4\pi {u}^{2}} as ∣u∣→+∞| u| \to +\infty . For a L2{L}^{2}-critical or L2{L}^{2}-subcritical perturbation μ∣u∣p−2u\mu {| u| }^{p-2}u, we investigate the existence of normalized solutions to the aforementioned problem. Moreover, the limiting profiles of solutions have been considered as μ→0\mu \to 0 or a→0a\to 0. This result can be considered as a supplement to the work of Soave (Normalized ground states for the NLS equation with combined nonlinearities: the Sobolev critical case, J. Funct. Anal. 279 (2020), no. 6, 1–43) and Alves et al. (Normalized solutions for a Schrödinger equation with critical growth in RN{{\mathbb{R}}}^{N}, Calc. Var. Partial Differential Equations 61 (2022), no. 1, 1–24).

According to understanding of the pathogenesis of acne, scholars have established animal models of acne inflammation, animal models of grafting human skin acne, and natural acne animal models. The acne inflammation model is mainly induced by bacterial infection, chemical drug application, and foreign matter injection. Natural acne animal models include animals that some are sensitivity to hormones and some have clinical symptoms of acne. It is necessary to select appropriate model animals and replicate model methods for the development of acne intervention products with different degrees and mechanisms. At present, there are only human evaluation standards of acne health functions in China, but no animal evaluation standards, which has affected the in-depth study of the pathogenesis of acne as well as the research and development progress of acne products. This article summarizes the conditions for the occurrence of acne, the characteristics of human skin, the bidirectional effect of Cutibacterium acnes on human skin, acne animal models, and commonly used observation and evaluation indicators, providing the reference for studying the pathogenesis of acne, promoting acne treatment and health care, and developing treatment products.

We are concerned with the following coupled nonlinear Schrödinger system: −Δu+u+∫∣x∣∞h(s)su2(s)ds+h2(∣x∣)∣x∣2u=∣u∣2p−2u+b∣v∣p∣u∣p−2u,x∈R2,−Δv+ωv+∫∣x∣∞g(s)sv2(s)ds+g2(∣x∣)∣x∣2v=∣v∣2p−2v+b∣u∣p∣v∣p−2v,x∈R2,\left\{\begin{array}{l}-\Delta u+u+\left(\underset{| x| }{\overset{\infty }{\displaystyle \int }}\frac{h\left(s)}{s}{u}^{2}\left(s){\rm{d}}s+\frac{{h}^{2}\left(| x| )}{{| x| }^{2}}\right)u={| u| }^{2p-2}u+b{| v| }^{p}{| u| }^{p-2}u,\hspace{1em}x\in {{\mathbb{R}}}^{2},\hspace{1.0em}\\ -\Delta v+\omega v+\left(\underset{| x| }{\overset{\infty }{\displaystyle \int }}\frac{g\left(s)}{s}{v}^{2}\left(s){\rm{d}}s+\frac{{g}^{2}\left(| x| )}{{| x| }^{2}}\right)v={| v| }^{2p-2}v+b{| u| }^{p}{| v| }^{p-2}v,\hspace{1em}x\in {{\mathbb{R}}}^{2},\hspace{1.0em}\end{array}\right. where ω,b>0\omega ,b\gt 0, p>1p\gt 1. By virtue of the variational approach, we show the existence of nontrivial ground-state solutions depending on the parameters involved. Precisely, the aforementioned system admits a positive ground-state solution if p>3p\gt 3 and b>0b\gt 0 large enough or if p∈(2,3]p\in \left(2,3] and b>0b\gt 0 small.

We are concerned with the following Kirchhoff-type equation with exponential critical nonlinearities −a+b∫R2∣∇u∣2dxΔu+(h(x)+μV(x))u=K(x)f(u)inR2,-\left(a+b\mathop{\int }\limits_{{{\mathbb{R}}}^{2}}| \nabla u{| }^{2}{\rm{d}}x\right)\Delta u+\left(h\left(x)+\mu V\left(x))u=K\left(x)f\left(u)\hspace{1em}{\rm{in}}\hspace{0.33em}{{\mathbb{R}}}^{2}, where a,b,μ>0a,b,\mu \gt 0, the potential VV has a bounded set of zero points and decays at infinity as ∣x∣−γ| x{| }^{-\gamma } with γ∈(0,2)\gamma \in \left(0,2), the weight KK has finite singular points and may have exponential growth at infinity. By using the truncation technique and working in some weighted Sobolev space, we obtain the existence of a mountain pass solution for μ>0\mu \gt 0 large and the concentration behavior of solutions as μ→+∞\mu \to +\infty .

In this paper, we consider the following critical fractional magnetic Choquard equation: ε2s(−Δ)A∕εsu+V(x)u=εα−N∫RN∣u(y)∣2s,α∗∣x−y∣αdy∣u∣2s,α∗−2u+εα−N∫RNF(y,∣u(y)∣2)∣x−y∣αdyf(x,∣u∣2)uinRN,\begin{array}{rcl}{\varepsilon }^{2s}{\left(-\Delta )}_{A/\varepsilon }^{s}u+V\left(x)u& =& {\varepsilon }^{\alpha -N}\left(\mathop{\displaystyle \int }\limits_{{{\mathbb{R}}}^{N}}\frac{| u(y){| }^{{2}_{s,\alpha }^{\ast }}}{| x-y\hspace{-0.25em}{| }^{\alpha }}{\rm{d}}y\right)| u\hspace{-0.25em}{| }^{{2}_{s,\alpha }^{\ast }-2}u\\ & & +{\varepsilon }^{\alpha -N}\left(\mathop{\displaystyle \int }\limits_{{{\mathbb{R}}}^{N}}\frac{F(y,| u(y){| }^{2})}{| x-y\hspace{-0.25em}{| }^{\alpha }}{\rm{d}}y\right)\hspace{0.08em}f\left(x,| u\hspace{-0.25em}{| }^{2})u\hspace{1em}{\rm{in}}\hspace{0.33em}{{\mathbb{R}}}^{N},\end{array} where ε>0\varepsilon \gt 0, s∈(0,1)s\in \left(0,1), α∈(0,N)\alpha \in \left(0,N), N>max{2μ+4s,2s+α∕2}N\gt {\rm{\max }}\left\{2\mu +4s,2s+\alpha /2\right\}, 2s,α∗=2N−αN−2s{2}_{s,\alpha }^{\ast }=\frac{2N-\alpha }{N-2s} is the upper critical exponent in the sense of Hardy-Littlewood-Sobolev inequality, (−Δ)As{\left(-\Delta )}_{A}^{s} stands for the fractional Laplacian with periodic magnetic field AA of C0,μ{C}^{0,\mu }-class with μ∈(0,1]\mu \in (0,1] and VV is a continuous potential and allows to be sign-changing. Under some mild assumptions imposed on VV and ff, we establish the existence of at least one ground state solution.

Semiconductor mode-locked lasers (MLLs) can provide coherent optical frequency combs (OFCs) with high repetition rates and output power, which have been recognized as potential multi-wavelength sources used in optical communication field due to their compactness, high-efficiency, and low-cost properties. In this article, we have reviewed recent development of semiconductor MLL-based frequency comb generation. Different approaches of semiconductor MLLs for OFC generation are synoptically summarized based on various material platforms. The representative progress of III-V semiconductor MLLs on III-V platform and especially on Si substrates is both discussed for the applications in integrated silicon photonics.

We are concerned with a class of Choquard type equations with weighted potentials and Hardy–Littlewood–Sobolev lower critical exponent

Extracting degradation features is an important part of Monitoring the health status of machinery. The performance of degradation features fluctuates or even declines with the continuous operation of the rotating machinery for a long time, which makes it difficult to extract and select degradation features. First, a feature mapping Algorithm library was used to extract features from the vibration signals and the original feature set was filtered based on Kolmogorov-smirnov（KS） test and Benjamini-Yekutieli process. Then, the optimal feature subset was searched in the supervised environment by combining BOGA with SVC. The accuracy of SVC and the dimension of subset were two objective functions of BOGA, the former was maximized, the latter was minimized. The performance of proposed method was verified by the experiment on the data set of hydraulic pump degradation state and the comparison with FRESHPCAa, ReliefF and JMIM on the case western reserve university bearing data set.

Spherical parallel mechanisms with large or fully spherical workspace are one of the important research directions in the application of large-angle workspace. Aiming at the problem of insufficient workspace in the current spherical parallel mechanisms，a new idea for the type design of a 2-DOF decoupled parallel mechanism with a fully spherical workspace is presented based on the input and output characteristics of the double rocker mechanism. And a newly decoupled parallel mechanism (RR&P5R) with a fully spherical workspace is designed. The kinematic equations of parallel mechanism are established through kinematic analysis. Then the relationship of displacement，velocity and acceleration between input and output for the RR&P5R mechanism are obtained. With the objective of the minimum input quantity q2，the size of the RR&P5R mechanism is optimized. This research provides an important theoretical basis for large-angle spherical workspace applications.

We are concerned with the following quasilinear elliptic equation

In order to study the dynamic characteristics and fatigue life of the plow bit-holede in the cutting process,according to the coal sample property and structure and motion parameters of plow,the random load of BH38/2 × 400 type coal plow bit was calculated by a software system of coal plow design and calculation. The load was applied to the multi body system model of the coal plow.The dynamic stress and the deformation distribution of the bit-holder in the working process were obtained by dynamic simulation. The fatigue life of the bit-holder was predicted by the rain flow counting of the stress information.Research results show that: under the action of complex mechanics with coal,the load of plow bit is non-linear. Under the action of nonlinear load,the areas with higher dynamic stresses are mainly concentrated in the contact position between rectangular groove of bit-holder and the back of plow bit,and the position of the square screw also suffered higher dynamic stresse. The cumulative fatigue damage of the bit-holder was analyzed by rain flow counting method,and the fatigue life was predicted to be about 475. 7 days. According to the comparison between the test value and the calculated value of plow bit,combined with the practical application feedback of the plow,the accuracy of the simulation results was verified.

For the inaccuracy of empirical heat loads for spindle thermal simulations,a thermal simulation analysis method onto motorized spindle unit is proposed.Firstly,the fluid-solid-heat coupling simulation model of the motorized spindle unit is established by Ansys Workbench,with the coolant dynamic heat transfer and thermal resistances of bearing inner-spindle shaft and outer rings-bearing housing being considered.Secondly,based on the simulation model,genetic algorithm is used to optimize and correct the heat generation values of spindle motor/beairngs and ambient heat transfer coefficients.The corrected values above are used as thermal loads for thermal simulation modeling of motorized spindle unit.Based on the model,the dynamic relationship between the heat dissipation power of the coolants and the heat generation power of spindle motor/beairngs is studied.Finally,the model accuracy is verified by the spindle temperature testing experiment.The results show that the optimization correction model can effectively improve the temperature field simulation accuracy of the motorized spindle unit,and the spindle structure and the coolant reach the optimal heat-heating balance when the coolant supply temperature is about 2℃ lower than the ambient temperature.

A method for control of three-phase unbalanced load based on variable frequency power was proposed in this paper. The general idea was introduced firstly, and then the implementation of the scheme and the design method of variable frequency power supply and the realization scheme of the master control center at the side of low-voltage distribution network was described in details. When three-phase unbalance occurs in the power grid, the general control center sends phase-changing instructions, and the inverter power supply receives instructions to perform phase-changing, and the normal work of the load is not affected in the phase-changing process, which can effectively solve the problem of three-phase unbalance in the power grid. By setting up the basic model of low-voltage side commutation with variable frequency power as the core, the rationality of the commutation process is simulated and analyzed by MATLAB, and finally the feasibility of three-phase unbalanced control scheme with frequency conversion power as the core is verified by experiments.

As one of the core components of the RF power system, the RF power source has a fixed frequency and low conversion efficiency, which has become a bottleneck restricting the development of the RF power system. Aiming at this problem, a design scheme for freely switching the RF power source between dual frequency operation modes is proposed. Direct Digital Synthesizer is used as the RF signal source. The MOSFTE producted by IXYS Company of Germany is used to achieve the amplification of small signals, which improves conversion efficiency and the stability of the output frequency. The method of parallel inductors reduces power loss during switching time. Switching the frequency selection network with a digital-controlled switch achieves adaptation of the system at dual frequencies. At the same time, Multisim simulation is carried out on the proposed scheme and theory. After actual testing, the RF power source can achieve dual frequency selection output of 13.56 MHz and 27.12 MHz at 300 W, and the conversion efficiency can reach 90.1%.

Based on the TensorFlow framework, this paper builds convolutional neural networks to recognize the defects in the electroluminescent images of cells. It selects the exposed data set that contains the different types of defects in the cell. Based on the traditional VGGNet network, the full convolution neural network is used for training, and this paper analyzes the training effects of different loss functions and dropout probabilities on data set. Experiments have shown that the algorithm accurately recognizes whether the cell is defective. The study also shows that the compression network structure greatly increases the training rate of the algorithm, which makes the simplified model more portable and provides an effective solution for a wide range of real-time defect recognition.

In this paper, we are concerned with the existence and concentration phenomena of solutions for the following singularly perturbed fractional Schrödinger problem:

We are concerned with the existence of ground states and qualitative properties of solutions for a class of nonlocal Schrödinger equations. We consider the case in which the nonlinearity exhibits critical growth in the sense of the Hardy–Littlewood–Sobolev inequality, in the range of the so-called upper-critical exponent. Qualitative behavior and concentration phenomena of solutions are also studied. Our approach turns out to be robust, as we do not require the nonlinearity to enjoy monotonicity nor Ambrosetti–Rabinowitz-type conditions, still using variational methods.

Aiming at the workspace of existing spherical parallel mechanism is smaller in the field of large spherical workspace application,a decoupling spherical parallel mechanism with sphere workspace is proposed.Firstly,according to the limitation from the friction circle of the revolute joint,the modified mechanism is given,which can provide a sphere workspace,and its number of degree of freedom is analyzed. Secondly,the inverse and forward position for the mechanism is derived with the closed vector method. The expression of the Jacobian matrix is deduced with the relational expression between the input and output parameters of the mechanism. And according to the expression of the Jacobian matrix,the decoupled feature of the proposed parallel mechanism is validated. The theoretical foundation for the application of the mechanism to the sphere workspace is provided.

PURPOSE: Identifying molecular and immune features to guide immune checkpoint inhibitor (ICI)-based regimens remains an unmet clinical need. EXPERIMENTAL DESIGN: Tissue and longitudinal blood specimens from phase III trial S1400I in patients with metastatic squamous non-small cell carcinoma (SqNSCLC) treated with nivolumab monotherapy (nivo) or nivolumab plus ipilimumab (nivo+ipi) were subjected to multi-omics analyses including multiplex immunofluorescence (mIF), nCounter PanCancer Immune Profiling Panel, whole-exome sequencing, and Olink. RESULTS: Higher immune scores from immune gene expression profiling or immune cell infiltration by mIF were associated with response to ICIs and improved survival, except regulatory T cells, which were associated with worse overall survival (OS) for patients receiving nivo+ipi. Immune cell density and closer proximity of CD8+GZB+ T cells to malignant cells were associated with superior progression-free survival and OS. The cold immune landscape of NSCLC was associated with a higher level of chromosomal copy-number variation (CNV) burden. Patients with LRP1B-mutant tumors had a shorter survival than patients with LRP1B-wild-type tumors. Olink assays revealed soluble proteins such as LAMP3 increased in responders while IL6 and CXCL13 increased in nonresponders. Upregulation of serum CXCL13, MMP12, CSF-1, and IL8 were associated with worse survival before radiologic progression. CONCLUSIONS: The frequency, distribution, and clustering of immune cells relative to malignant ones can impact ICI efficacy in patients with SqNSCLC. High CNV burden may contribute to the cold immune microenvironment. Soluble inflammation/immune-related proteins in the blood have the potential to monitor therapeutic benefit from ICI treatment in patients with SqNSCLC.

The paper focuses on the effects of the cell wall material strain hardening on the mechanical behavior of closed-cell foams subjected to the constant velocity loading. Three-dimensional Voronoi models were established to present the closed-cell foams, and the simulations were performed by employing Ls-dyna 971. The investigation found that the cell wall strain hardening could postpone the onset of the localized collapse bands and retard deformation mode transformation. Strain hardening convergence phenomenon was observed in the closed-cell foams; increasing the impact velocity could weaken the effect of the material strain hardening. The crushing stress at both impact and stationary sides were analyzed in detail. The material strain hardening could always enhance the plastic energy dissipation. Furthermore, the strain hardening convergence was also observed in the plateau stress at the impact side and plastic energy dissipation but not in the densification strain and the plateau at the stationary side.

The selective harmonic elimination(SHE) based staircase modulation is a commonly used fundamental frequency modulation strategy for multilevel converters.However, the solutions to the staircase SHE equations cannot cover the full range of modulation index, which limits the applications of this modulation method.In order to solve this problem, this paper extends the staircase switching pattern to the general switching patterns, in which, the Groebner bases method is used to solve the SHE equations, and the achievable range of modulation index and the complete solutions for each switching patterns are obtained.By evaluating the total harmonic distortion, the optimal switching pattern and the corresponding optimal switching angles can be identified for the modulation indices in full range.Experiment results verify the correctness of the proposed method.

In November 2018, the lidar-based wind shear synchronous experiment was performed at Beijing Capital International Airport (BCIA). In this experiment, aiming at the measurement of the terrain-induced wind shear and the wind field around the runway, the glide path scanning mode, and the RHI strategy were conducted alternately. Radial velocity retrieved from the glide path scanning can obviously present the wakes caused by complex terrain (e.g., hills, tall trees, residential and terminal buildings). The Pulse Coherent Doppler Lidar (PCDL) warned the terrain-induced wind shear, which was verified by the pilot report. The wind field structure around the runway under the wake effect and the building shielding effect is also analyzed.