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The Genetic Algorithm-Extreme Learning Machine (GA-ELM) neural network algorithm is proposed to model the relevant characteristics of GaN pseudomorphic high electron mobility transistor (P-HEMT) large signal. This algorithm solves the over-fitting problem of the Back Propagation (BP) neural network algorithm in the prediction data. It has the characteristics of fast calculation speed, so it can greatly save calculation processing time. It can also randomly generate the connection weights of the input layer, the hidden layer and the threshold of the hidden layer neurons, avoiding errors in parameter selection. In order to verify the superiority of the algorithm, the modeling effects of the BP neural network algorithm model, the Genetic Algorithm-Back Propagation (GA-BP) neural network algorithm model and the GA-ELM neural network algorithm model are compared in this paper. The results show that the proposed GA-ELM neural network algorithm model has the highest accuracy. [ABSTRACT FROM AUTHOR]

A numerical analysis is presented for the oscillatory flow of Maxwell fluid in a rectangular straight duct subjected to a simple harmonic periodic pressure gradient. The numerical solutions are obtained by a finite difference scheme method. The stability of this finite difference scheme method is discussed. The distributions of the velocity and phase difference are given numerically and graphically. The effects of the Reynolds number, relaxation time, and aspect ratio of the cross section on the oscillatory flow are investigated. The results show that when the relaxation time of the Maxwell model and the Reynolds number increase, the resonance phenomena for the distributions of the velocity and phase difference enhance. [ABSTRACT FROM AUTHOR]

On the basis of Darcy–Brinkman model, linear stability analysis is used to study bio-thermal convection in a suspension of gyrotactic microorganisms in a highly porous medium heated from below. A Galerkin method is performed to solve the governing equations generating a correlation between the traditional thermal Rayleigh number and the critical value of the bioconvection Rayleigh number. The effects of three variables including the bioconvection Péclet number, the gyrotaxis number and the modified Darcy number on both the wave number and the critical bioconvection Rayleigh number are analyzed and shown graphically. Results indicate that the critical bioconvection Rayleigh number becomes larger with increasing Darcy number. [ABSTRACT FROM AUTHOR]

Purpose: To determine the role of Indian hedgehog (Ihh) signaling in human cartilage endplate (CEP) degeneration. Methods: CEP-degenerated tissues from patients with Modic I or II changes ( n = 9 and 45, respectively) and normal tissues from vertebral burst fracture patients ( n = 17) were collected. Specimens were either cut into slices for organ culture ex vivo or digested to isolate chondrocytes for cell culture in vitro. Ihh expression and the effect of Ihh on cartilage degeneration were determined by investigating degeneration markers in this study. Results: Ihh expression and cartilage degeneration markers significantly increased in the Modic I and II groups. The expression of cartilage degeneration markers was positively correlated with degeneration severity. Gain-of-function for Ihh promoted expression of cartilage degeneration markers in vitro, while loss-of-function for Ihh inhibited their expression both in vitro and ex vivo. Conclusions: These findings demonstrated that Ihh promotes CEP degeneration. Blocking Ihh pathway has potential clinical usage for attenuating CEP degeneration. [ABSTRACT FROM AUTHOR]

To better deal with high dimensions and extract the essential feature of facial expression images in facial expression recognition task, a novel approach integrating radial basis function kernel and multidimensional scaling analysis is proposed in this paper. Firstly, the radial basis function kernel is invoked to map facial expression images to the Hilbert space. Then, Hilbert distance is substituted for the Euclidean distance and a neighbor graph is constructed to express the relationship between data points by employing k nearest neighbor method. Finally, we apply the modified MDS algorithm to reduce the dimension and extract features of facial expression images. Experiments results on the JAFFE database show that this proposed algorithm performs better than Isomap algorithm and supervised Isomap algorithm, and it is more feasible and effective. [ABSTRACT FROM AUTHOR]

In this paper, we study the resource allocation problem in multiuser Orthogonal Frequency Division Multiplexing (OFDM)-based cognitive radio networks. The interference introduced to Primary Users (PUs) is fully considered, as well as a set of proportional rate constraints to ensure fairness among Secondary Users (SUs). Since it is extremely computationally complex to obtain the optimal solution because of integer constraints, we adopt a two-step method to address the formulated problem. Firstly, a heuristic subchannel assignment is developed based on the normalized capacity of each OFDM subchannel by jointly considering channel gain and the interference to PUs, which approaches a rough proportional fairness and removes the intractable integer constraints. Secondly, for a given subchannel assignment, we derive a fast optimal power distribution algorithm that has a complexity of O( L N) by exploiting the problem's structure, which is much lower than standard convex optimization techniques that generally have a complexity of O(( N + K)), where N, L and K are the number of subchannels, PUs and SUs, respectively. We also develop a simple power distribution algorithm with complexity of only O( L + N), while achieving above 90 % sum capacity of the upper bound. Experiments show that our proposed algorithms work quite well in practical wireless scenarios. A significant capacity gain is obtained and the proportional fairness is satisfied perfectly. [ABSTRACT FROM AUTHOR]

While smoking is widely acknowledged as a risk factor for rheumatoid arthritis (RA), the connection between secondhand smoke (SHS) exposure and RA in never-smoking adults remains limited and inconsistent. This study aims to explore and quantify this association using serum cotinine levels. We conducted a cross-sectional study with 14,940 adults who self-report as never smokers, using National Health and Nutrition Examination Survey data from 1999 to 2018. Based on previous literature, SHS exposure was categorized into four groups according to serum cotinine levels. Compared to individuals in the unexposed group (serum cotinine < 0.05 ng/mL), the adjusted odds ratio (OR) for RA was 1.37 (95% CI 1.14–1.64, p = 0.001) in the low exposure group (serum cotinine at 0.05 to 0.99 ng/mL) after adjusting for covariates. However, no significant association was found in the moderate exposure group (serum cotinine at 1 to 10 ng/mL) or the heavy exposure group (serum cotinine ≥ 10 ng/mL). Furthermore, we detected a non-linear, positively saturated correlation between the cotinine levels after log2 transformation and RA, with a turning point at approximately − 2.756 ng/mL (OR = 1.163, 95% CI 1.073–1.261, p = 0.0002). The stability of the results was confirmed by subgroup analysis. [ABSTRACT FROM AUTHOR]

The thermal convection of a Jeffreys fluid subjected to a plane Poiseuille flow in a fluid-porous system composed of a fluid layer and a porous layer is studied in the paper. A linear stability analysis and a Chebyshev τ-QZ algorithm are employed to solve the thermal mixed convection. Unlike the case in a single layer, the neutral curves of the two-layer system may be bi-modal in the proper depth ratio of the two layers. We find that the longitudinal rolls (LRs) only depend on the depth ratio. With the existence of the shear flow, the effects of the depth ratio, the Reynolds number, the Prandtl number, the stress relaxation, and strain retardation times on the transverse rolls (TRs) are also studied. Additionally, the thermal instability of the viscoelastic fluid is found to be more unstable than that of the Newtonian fluid in a two-layer system. In contrast to the case for Newtonian fluids, the TRs rather than the LRs may be the preferred mode for the viscoelastic fluids in some cases. [ABSTRACT FROM AUTHOR]

Smart grid is in need of an efficient communication network to guarantee reliable two-way data transmission between the control center and smart meters (SMs). In this work, a software-defined networking (SDN) based smart grid communication (SGC) scheme is introduced to fulfill the information transmission requirement, where the control plane is separated from the data plane to support diverse services flexibly in the smart grid. In such an SDN-based SGC system, to guarantee effective data processing and forwarding between the SMs and the control center, aggregation points (APs) are introduced. These APs should be deployed in an optimal way so as to cut down the total capital expenditure of the SGC system. The total cost generally includes the transmission cost between APs and the control center as well as APs and SMs. The construction and maintenance cost of the APs is also included. An approximation algorithm is introduced in this paper. The algorithm can deal with the formulated intractable APs planning task and produce performance-guaranteed solutions with reasonable complexity. Experiments indicate that the proposed algorithm works well for geographical areas with different densities of SMs. Our proposal yields cost-efficient APs deployment scheme and sheds insight into the reduction of the capital expenditure of the SGC system. [ABSTRACT FROM AUTHOR]

Trichuris (whipworm) infects 1 billion people worldwide and causes a disease (trichuriasis) that results in major socioeconomic losses in both humans and pigs. Trichuriasis relates to an inflammation of the large intestine manifested in bloody diarrhea, and chronic disease can cause malnourishment and stunting in children. Paradoxically, Trichuris of pigs has shown substantial promise as a treatment for human autoimmune disorders, including inflammatory bowel disease (IBD) and multiple sclerosis. Here we report whole-genome sequencing at ∼140-fold coverage of adult male and female T. suis and ∼80-Mb draft assemblies. We explore stage-, sex- and tissue-specific transcription of mRNAs and small noncoding RNAs. [ABSTRACT FROM AUTHOR]

Thin films of molecularly imprinted sol–gel polymer with specific binding sites for trichlorfon were prepared, fixed on glassy carbon electrodes and used as recognition material. The binding characteristic of the imprinted films to trichlorfon was evaluated by equilibrium binding experiments; and, the morphology was studied by scanning electronic microscope. A novel electrochemical sensor for determination of trichlorfon was developed based on the reaction between trichlorfon and the molecularly imprinted sol–gel film, which was a modified glassy carbon electrode. The sensor displayed excellent selectivity and high sensitivity. The linear response range of the sensor was 10 −8 –10 −6 g mL −1, and the limit of detection was 2.8 × 10 −9 g mL −1. The relative standard deviation for the determination of 10 −7 g mL −1 trichlorfon was 3.5%. The sensor was applied to the determination of trichlorfon in vegetables with satisfactory results. [ABSTRACT FROM AUTHOR]