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Polar codes, as the coding scheme for the control channel in fifth-generation mobile communication technology (5G), have attracted widespread attention since their proposal. As a mainstream decoding algorithm for polar codes, the successive cancellation list (SCL) decoder usually improves the error correction performance by increasing the list size, but this method suffers from the problems of high decoding complexity. To address this problem, this paper proposes a layered-search bit-flipping (LS-SCLF) decoding algorithm based on SCL decoding. Firstly, a new flip-bit metric is proposed, which derives a formula to approximate the probability of an error occurring in an information bit. This formula introduces a perturbation parameter to improve the calculation accuracy. Secondly, a compromise scheme for determining the perturbation parameter is proposed. The scheme uses Monte Carlo simulation to determine an optimized parameter for the precise positioning of the first erroneous decoded bit under different decoding conditions. Finally, a layered search strategy is adopted to sequentially search the erroneous decoded bits from the low order to high order, which can correct up to multiple bits at the same time. Simulation results show that the proposed algorithm achieves improved error correction performance with a slight increase in decoding complexity compared to the generalized SCL-Flip (GSCLF) decoding algorithm. This algorithm also achieves a good balance between the error correction performance and decoding complexity. [ABSTRACT FROM AUTHOR]

Dynamic range and spurious-free dynamic range are two of the most critical performance indexes in the field of radio frequency (RF). However, the definitions of both the indexes are ambiguous, and their characterization ability is insufficient, resulting in unfair, and even mutually incompatible, performance evaluation in practice. In this study, a new index named radio frequency distortion dynamic range and its corresponding evaluation method are proposed to achieve a fair and detailed dynamic range evaluation by unifying the existing definitions and improving the performance resolution ability. First, the sliding threshold selection method is introduced to replace the classification-based method of dynamic range definition to characterize more details of the dynamic range. Second, a dynamic range evaluation method of "performance body" is proposed to obtain a more comprehensive evaluation by generalizing the current evaluation from being based on a single condition to the one based on scanning critical conditions. Experiments show that the proposed radio frequency distortion dynamic range index with the proposed evaluation method reduces the ambiguity of dynamic range evaluation and can distinguish the performance difference that the current indexes cannot do. [ABSTRACT FROM AUTHOR]

Pulmonary arterial hypertension (PAH) is a pulmonary vascular disease characterized by the progressive elevation of pulmonary arterial pressures. It is becoming increasingly apparent that inflammation contributes to the pathogenesis and progression of PAH. Several viruses are known to cause PAH, such as severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), human endogenous retrovirus K(HERV-K), and human immunodeficiency virus (HIV), in part due to acute and chronic inflammation. In this review, we discuss the connections between HERV-K, HIV, SARS-CoV-2, and PAH, to stimulate research regarding new therapeutic options and provide new targets for the treatment of the disease. [ABSTRACT FROM AUTHOR]

Deep neural networks (DNNs) have been known to be vulnerable to adversarial attacks. Adversarial training (AT) is, so far, the only method that can guarantee the robustness of DNNs to adversarial attacks. However, the robustness generalization accuracy gain of AT is still far lower than the standard generalization accuracy of an undefended model, and there is known to be a trade-off between the standard generalization accuracy and the robustness generalization accuracy of an adversarially trained model. In order to improve the robustness generalization and the standard generalization performance trade-off of AT, we propose a novel defense algorithm called Between-Class Adversarial Training (BCAT) that combines Between-Class learning (BC-learning) with standard AT. Specifically, BCAT mixes two adversarial examples from different classes and uses the mixed between-class adversarial examples to train a model instead of original adversarial examples during AT. We further propose BCAT+ which adopts a more powerful mixing method. BCAT and BCAT+ impose effective regularization on the feature distribution of adversarial examples to enlarge between-class distance, thus improving the robustness generalization and the standard generalization performance of AT. The proposed algorithms do not introduce any hyperparameters into standard AT; therefore, the process of hyperparameters searching can be avoided. We evaluate the proposed algorithms under both white-box attacks and black-box attacks using a spectrum of perturbation values on CIFAR-10, CIFAR-100, and SVHN datasets. The research findings indicate that our algorithms achieve better global robustness generalization performance than the state-of-the-art adversarial defense methods. [ABSTRACT FROM AUTHOR]

Background: CYP4 subfamily V member 2 (CYP4V2) polymorphisms are related to venous thromboembolism. However, the influence of CYP4V2 polymorphisms on the susceptibility to ischemic stroke (IS) remains undetermined. Methods: We selected and genotyped five polymorphisms of CYP4V2 in 575 cases and 575 controls to test whether CYP4V2 variants were associated with the risk for IS in a Chinese Han population. Genotyping of CYP4V2 polymorphisms was performed using the Agena MassARRAY platform. Logistic regression analysis was used to assess the association between CYP4V2 polymorphisms and IS risk by calculating odds ratios (ORs) and 95% confidence interval (CI). False-positive report probability analysis was applied to assess the noteworthy relationship of the significant findings. Results: CYP4V2 rs1398007 might be a risk factor for IS (OR = 1.34, 95% CI 1.05–1.71, p = 0.009). Specially, confounding factors (age, gender, smoking and drinking status) might affect the relationship between rs1398007 and IS susceptibility. Moreover, rs1053094 and rs56413992 were associated with IS risk in males. Multifactor dimensionality reduction analysis showed the combination of rs13146272 and rs3736455 had the strongest interaction effect (information gain value of 0.40%). Furthermore, genotypes of rs1398007 (p = 0.006) and rs1053094 (p = 0.044) were associated with the levels of high-density lipoprotein cholesterol (HDL-C) among healthy controls. Conclusion: Our results first provided evidence that CYP4V2 rs1398007 might be a risk factor for IS, which provides instructive clues for studying the mechanisms of CYP4V2 to the pathogenesis of IS. [ABSTRACT FROM AUTHOR]

Pitch estimation is widely used in speech and audio signal processing. However, the current methods of modeling harmonic structure used for pitch estimation cannot always match the harmonic distribution of actual signals. Due to the structure of vocal tract, the acoustic nature of musical equipment, and the spectrum leakage issue, speech and audio signals' harmonic frequencies often slightly deviate from the integer multiple of the pitch. This paper starts with the summation of residual harmonics (SRH) method and makes two main modifications. First, the spectral peak position constraint of strict integer multiple is modified to allow slight deviation, which benefits capturing harmonics. Second, a main pitch segment extension scheme with low computational cost feature is proposed to utilize the smooth prior of pitch more efficiently. Besides, the pitch segment extension scheme is also integrated into the SRH method's voiced/unvoiced decision to reduce short-term errors. Accuracy comparison experiments with ten pitch estimation methods show that the proposed method has better overall accuracy and robustness. Time cost experiments show that the time cost of the proposed method reduces to around 1/8 of the state-of-the-art fast NLS method on the experimental computer. [ABSTRACT FROM AUTHOR]

• A prototype-based method to sample landslide data. • The "mutual exclusion" was proposed to set reliability threshold. • Prototype-based sampling was better than existing sampling method. Spatial data sampling can improve the performance in geo-spatial prediction. However, measuring the reliability of polygon-based data in sampling process is still a challenge. In this study, a reliability-based sampling (RBS) method was proposed to deal with this question and it was applied in landslide susceptibility mapping. First, the prototype of landslide was extracted from landslide polygon data, then, the reliability of landslide samples and non-landslide samples is measured using the similarity in environmental factor between the candidate samples and the prototype. The mutual exclusion reliability threshold setting method is used to collect the landslide samples and non-landslide samples with reliability over certain threshold. A case study demonstrates that the RBS method is better than existing representative method (i.e. Landslide entity) in terms of Accuracy and AUC with different sample sizes. In summary, The RBS is an efficient method to improve the spatial pattern of samples can also be applied to in other geo-spatial predictions. [ABSTRACT FROM AUTHOR]

Oxygen-doped transition metal disulfides solid lubricating films have been less investigated due to the widespread viewpoint of the detrimental effect of oxidation on tribological properties. In this study, the introduction of oxygen into the deposited W-S-O film was achieved through sputtering WS 2 /WO 3 composite targets. The hardness of W-S-O film has been found to increase threefold, accompanied by a 50% reduction in the friction coefficient and an order of magnitude increase in wear life. The compact structures and the embedded WO 3 nanocrystals in the film contribute to the improved tribological property of the W-S-O film by improving the load-bearing capacity. Meanwhile, the presence of WO 3 phase within the W-S-O film does not hinder the formation of the transfer film during friction. [Display omitted] • The presence of WO 3 nanocrystals in the W-S-O film resulted in a substantially thick equiaxed crystal layer. • The W-S-O film exhibited lower friction coefficient and longer wear life compared to that for pure WS 2 film. • The WO 3 phase was expelled from the tribo-surface without hindering transfer film formation during friction. [ABSTRACT FROM AUTHOR]

To study nitrogen transport monitoring in pear trees based on ground-based hyperspectral remote sensing and digital image information. First, based on ground hyperspectral remote sensing and digital image information, combined with the characteristics of visible and near-infrared spectral data and digital image data, a beet nitrogen nutrition diagnosis model based on visible and near-infrared spectral and digital image information was established. The results showed that under water and nitrogen management conditions, the marked nitrogen use efficiency at soil profiles 15, 45, and 75 cm was 28.2%, 22.3%, and 16.3%, respectively. From the analysis of soil and plant nitrogen measured in this experiment, it can be seen that nitrogen nitrate fertilizer should be properly applied to pear trees in the future. [ABSTRACT FROM AUTHOR]

In order to better monitor the data of nitrogen transport in pear leaves, a method based on infrared spectroscopy was proposed. The near-infrared reflection spectrum imaging technology is used to collect the leaf scale spectral image of the target crop. Computer image analysis software is used to process the spectral digital image and extract the spectral data. After statistical analysis, the data are selected as variables. Combined with the chemical analysis test results, the crop nutrition detection model is established, and the conclusion is drawn. The experimental results show that the band gray data involved in the model are scaled and reorganized according to the coefficient proportion by using ENVI through the band calculation command. The final gray image, the original image, and the gray image in the process default to the three-channel analog image of the band (the wavelengths of the bands are 1446, 1373, and 1304 nm, respectively); 944 nm gray image; 1043 nm gray scale image; 1662 nm gray image; (0.102R944 +0.103R1 043 +0.206R1662)/(0.102 + 0.103 + 0.206) grayscale image with signal scaling according to the scale of model coefficient. It is proved that infrared spectroscopy can effectively monitor the data of nitrogen transport in pear leaves. [ABSTRACT FROM AUTHOR]

Cascaded audio systems (CASs) widely exist in consumer electronics, within which volume control is one of the most basic functions. However, the current volume adjustment schemes cannot automatically achieve optimal control, leading to performance degradation of CASs. Meanwhile, there is a lack of mathematical models and quantitative analysis between CASs performance and volume control position. In this study, an optimal volume control architecture named local processing and amplification (LPA) is proposed to minimize the volume control’s adverse impact on CASs’ performance automatically. First, a general CAS model is established through effective analysis and reasonable equivalence of diverse complicated CASs. Second, the quantitative relationship between the volume control and the CAS performance is theoretically analyzed using the noise figure theory, hence, the LPA architecture is proposed. Finally, the proposed LPA’s performance improvement effect is analyzed and compared with the other volume controls in a wide volume range. Simulations and experiments using multiple indexes show that the signal-to-noise ratio (SNR) and the total harmonic distortion plus noise (THD+N) improvement of the proposed architecture are up to 5.2 dB and 4.8 dB, respectively, under a typical −9 dB volume. [ABSTRACT FROM AUTHOR]

Automatic speech recognition (ASR) is an essential technique of human–computer interactions; gain control is a commonly used operation in ASR. However, inappropriate gain control strategies can lead to an increase in the word error rate (WER) of ASR. As there is a current lack of sufficient theoretical analyses and proof of the relationship between gain control and WER, various unconstrained gain control strategies have been adopted on realistic ASR systems, and the optimal gain control with respect to the lowest WER, is rarely achieved. A gain control strategy named maximized original signal transmission (MOST) is proposed in this study to minimize the adverse impact of gain control on ASR systems. First, by modeling the gain control strategy, the quantitative relationship between the gain control strategy and the ASR performance was established using the noise figure index. Second, through an analysis of the quantitative relationship, an optimal MOST gain control strategy with minimal performance degradation was theoretically deduced. Finally, comprehensive comparative experiments on a Mandarin dataset show that the proposed MOST gain control strategy can significantly reduce the WER of the experimental ASR system, with a 10% mean absolute WER reduction at −9 dB gain. [ABSTRACT FROM AUTHOR]

The use of virtualization technology in industrial control is increasing. However, virtual instances or virtual machines (VMs) are confronted with the unreasonable resource allocation in the industrial control cyber range, thereby highlighting the increasing importance of resource scheduling. In the Xen open source system, the input–output (IO)-intensive task response is extended because the system does not distinguish between CPU- and IO-intensive tasks. Therefore, this article presents an improved task performance through the hybrid scheduling of CPU and network IO resources. This method uses Cap- and Timeslice-scheduling algorithms for CPU resource scheduling. First, the Cap-scheduling algorithm uses historical data to train a recurrent neural network model for classification and then utilizes the heuristic method to set the upper limit of cap value for VMs. Second, the Timeslice-scheduling algorithm adjusts the timeslice based on Q-learning to shorten the execution time of the overall tasks. This article proposes an IOb-scheduling algorithm for network bandwidth scheduling. The part that does not exceed the average bandwidth is eliminated and distributed to other VMs by monitoring the bandwidth usage of each VM, thereby improving the utilization of bandwidth. Experimental results showed that the proposed CPU/IO scheduling algorithms improved the overall benchmark performance substantially. [ABSTRACT FROM AUTHOR]

In view of the near slope blasting in Barun open-pit mine, which has merged sublevel mining, the operation safety conditions of middle-sized and large equipment in the second phase expansion are poor and need urgent improvement. To increase the efficiency of expansion and reduce costs, a 24-m-high bench and large spacing parameter for loosening blasting are proposed. The analysis of the physical mechanism of the stress wave attenuation in the rock indicates that the cylindrical charge is equivalent to several spherical charges. Considering the pressure attenuation, reflection, transmission, and superposition of the spherical charge after the equivalence, a double exponential function correction equation of the stress wave attenuation is obtained based on the Mises strength criterion. The stress of any point in the rock medium with various spacing parameter is obtained by calculation. ANSYS/LS-DYNA was used to simulate and study the stress distribution of a 24-m-high bench with various spacing parameter. Meanwhile, the accuracy of the correction equation was verified. The parameters of the high-bench blasting with good effect and low cost were determined to be 15 m × 5.5 m, and field tests were carried out. Results show that the large spacing parameter for 24-m-high bench loosening blasting in Barun open-pit mine is efficient and economical in medium-hard rock blasting. This study provides a reference for the practical exploration of the expansion of high benches in open-pit mines in China. The calculation error of the corrected double exponential function is near the numerical simulation result. It is suitable for all kinds of professional designers. [ABSTRACT FROM AUTHOR]

Millisecond-delay blasting in an open pit is difficult because the development of rock mass horizontal layering and mechanical properties vary widely among rocks. An unreasonable delay time for varied holes and rows often causes poor blasting effects. In this study, the multi-layer rock blasting model in the ANSYS/LS-DYNA software is used to optimize the delay time between holes and rows, improve the blasting effect, and reduce the vibration produced by blasting. The delay time for varied holes and rows is simulated. In line with the evaluation model of the entropy weight method, the maximum effective stress in the three sections is analyzed. The weight coefficient of each index is determined with entropy information theory, and a rock damage model is established. The ratio between the maximum tangential stress of the surrounding rock and the uniaxial compressive strength of the rock and the ratio of the uniaxial compressive strength of the rock to its tensile strength are selected as evaluation indicators. The maximum effective stress in the three sections at different positions between holes and rows is determined and analyzed. The test indicates that the delay time combination of 28 and 100 ms is effective and can avoid the interference of various geological conditions on the blasting effect. In accordance with the evaluation results, this delay time combination is used for field tests. Results demonstrate that the blasting effect of the selected delay time combination is remarkably enhanced, the boulder frequency is low, and the vibration caused by blasting is reduced by 30%. In special geological conditions where the mechanical properties of rocks differ greatly, the evaluation model of the entropy weight method presents crucial advantages in the precise selection of millisecond-delay intervals for horizontal layering bench blasting. [ABSTRACT FROM AUTHOR]

Simple Summary: Eyeblink conditioning is a simple form of learning that has been used to study areas of the brain involved in how we learn new tasks and how we remember them. One area of the brain that is important for eyeblink conditioning is the cerebellum. Changes that take place in the cerebellum involve a number of neural processes, including changes in the connections between neurons, changes in a neuron's excitability, and even changes in the matrix that surrounds these neurons. Here, we explore these different processes and how they interact with each other to form the building blocks of a basic form of learning. Understanding how learning and memory take place may help us solve the mystery of how we lose the ability to learn and remember in diseases like Alzheimer's disease, and how to we remember too much in post-traumatic stress disorder. Evidence is strong that, in addition to fine motor control, there is an important role for the cerebellum in cognition and emotion. The deep nuclei of the mammalian cerebellum also contain the highest density of perineural nets—mesh-like structures that surround neurons—in the brain, and it appears there may be a connection between these nets and cognitive processes, particularly learning and memory. Here, we review how the cerebellum is involved in eyeblink conditioning—a particularly well-understood form of learning and memory—and focus on the role of perineuronal nets in intrinsic membrane excitability and synaptic plasticity that underlie eyeblink conditioning. We explore the development and role of perineuronal nets and the in vivo and in vitro evidence that manipulations of the perineuronal net in the deep cerebellar nuclei affect eyeblink conditioning. Together, these findings provide evidence of an important role for perineuronal net in learning and memory. [ABSTRACT FROM AUTHOR]

A recursion procedure for the analytical generation of hyperspherical harmonics for tetraatomic systems, in terms of row-orthonormal hyperspherical coordinates, is presented. Using this approach and an algebraic Mathematica program, these harmonics were obtained for values of the hyperangular momentum quantum number up to 30 (about 43.8 million of them). Their properties are presented and discussed. Since they are regular at the poles of the tetraatomic kinetic energy operator, are complete, and are not highly oscillatory, they constitute an excellent basis set for performing a partial wave expansion of the wave function of the corresponding Schro¨dinger equation in the strong interaction region of nuclear configuration space. This basis set is, in addition, numerically very efficient and should permit benchmark-quality calculations of state-to-state differential and integral cross sections for those systems. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Background: There is no guideline recommendation for preventing hepatocellular carcinoma (HCC) recurrence after hepatic resection. Moreover, an unmet need exists on the effectiveness of sorafenib therapy in recurrent HCC. Purpose: We therefore assessed the efficacy and safety of sorafenib in Chinese HCC patients with high risk of recurrence. Patients and methods: Data were collected retrospectively from 15 Chinese research centers from January 1, 2012 to November 15, 2013, by chart reviews of patients with moderate-advanced HCC who received hepatic carcinectomy. The primary end point was recurrence-free survival rate at 1 year in patients with a high recurrence risk. Secondary end points included 1-year survival rate, time to recurrence and safety assessment. Results: A total of 209 high-risk patients (sorafenib, n=98; control, n=111) who underwent carcinectomy were analyzed. There was no significant difference in the proportion of patients with recurrence-free survival at 1 year between the sorafenib and control (70.43% vs 68.90%: χ2=0.007, P=0.934). One-year survival rate was significantly higher with sorafenib than observed with control (95.5% vs 83.35%; χ2=7.441, P=0.006). Time to recurrence between sorafenib and control groups was similar. Incidences of all the adverse events (AEs) were similar in both the groups and transaminase elevation was most common in both groups (20.37% vs 24.79%). Thrombocytopenia incidence was significantly lower with the sorafenib group than with control (1.85% vs 9.40%; P=0.015). Conclusion: Sorafenib may be considered as a feasible option in the treatment of HCC recurrence. [ABSTRACT FROM AUTHOR]

Previous studies have shown tumor necrosis factor-alpha (TNF-α) may impact neurodegeneration in Alzheimer's disease (AD) by regulating amyloid-β and tau pathogenesis. However, it is unclear whether TNF-α has a role in a cholesterol-fed rabbit model of AD or TNF-α affects the electrophysiological properties of rabbit hippocampus. This study was designed to investigate whether long-term feeding of cholesterol diet known to induce AD pathology regulates TNF-α expression in the hippocampus and whether TNF-α would modulate electrophysiological properties of rabbit hippocampal CA1 neurons. TNF-α ELISA showed dietary cholesterol increased hippocampal TNF-α expression in a dose-dependent manner. Whole-cell recordings revealed TNF-α altered the membrane properties of rabbit hippocampal CA1 neurons, which was characterized by a decrease in after-hyperpolarization amplitudes; Field potential recordings showed TNF-α inhibited long-term potentiation but did not influence presynaptic function. Interestingly, TNF-α did not significantly affect the after-hyperpolarization amplitudes of hippocampal CA1 neurons from cholesterol fed rabbits compared to normal chow fed rabbits. In conclusion, dietary cholesterol generated an in vivo model of chronic TNF-α elevation and TNF-α may underlie the learning and memory changes previously seen in the rabbit model of AD by acting as a bridge between dietary cholesterol and brain function and directly modulating the electrophysiological properties of hippocampal CA1 neurons. [ABSTRACT FROM AUTHOR]

Abstract A novel approach by texturing the WS 2 film with the nanocone-array Ni interlayer was adopted to improve the tribological property of WS 2 film particularly prolonging the wear life for application in space. The WS 2 /Ni bilayer films were prepared by sputtering WS 2 layer onto electrodeposited Ni interlayers with different surface morphologies. The micro-structures and the tribological properties of the prepared WS 2 /Ni bilayer films were investigated. The results showed that with the existence of the nanocone-array Ni interlayer, the textured WS 2 film showed a cabbage-like structure due to the growth of the WS 2 columnar plates surrounding the Ni nanocones. The cabbage-like WS 2 /Ni bilayer thin film was benefited for improving the lubrication properties with a long wear life of 4.9 × 105 cycles while the wear life was only 0.7 × 105 cycles for the pure WS 2 and 3.2 × 105 cycles for rough Ni textured WS 2 film. The improved tribological property was mainly attributed to the reserve of the WS 2 lubricate by the Ni nanocones as well as the relative low friction coefficient of the nanocone-array Ni interlayer due to the obvious reduced real contact area. Highlights • A novel cabbage-like WS 2 /Ni bilayer film was prepared without any template. • The cabbage-like WS 2 /Ni bilayer lubricating film showed an improved lifetime. • Reservoir of the WS 2 lubricates by Ni nanocones resulted in the improved property. [ABSTRACT FROM AUTHOR]

Abstract The WS 2 /CrN bilayered films with different interface morphologies between WS 2 and CrN layer were prepared by physical vapor deposition. By controlling the deposition parameters, the surface of CrN interlayer exhibited compact granular structure when deposited under low partial pressure of Ar while a cone array-like surface appeared under high Ar partial pressure. The surface texture of the CrN interlayer had a great effect on the tribological performance of the WS 2 /CrN film. The compact CrN textured WS 2 film exhibited a wear life about 2.6 × 105 cycles while the optimal cone array-like CrN textured WS 2 film showed a much longer wear life reaching to 6.8 × 105 cycles, which was more than 2.6 times of that for compact CrN textured WS 2 film and 3.5 times of that for WS 2 film without the CrN interlayer. The improved tribological property of the optimal cone array-like CrN textured WS 2 film was attributed to the high adhesion between the WS 2 layer and the CrN interlayer. Meanwhile, the reservoir and replenishment of the WS 2 lubricant by the CrN nanocones during the friction made a significant contribution for the long wear life. Highlights • Compact and cone array-like CrN interlayers were deposited under different Ar partial pressure. • Different tribological performances would be resulted by tailoring the interface of WS 2 /CrN bilayered film. • The reservoir and replenishment of the WS 2 lubricates by CrN nanocone array contribute to the tribological performances. [ABSTRACT FROM AUTHOR]

We report reduced dimensionality coupled channel scattering calculations of rotationally averaged cross sections for the H+C2H2H2+C2H reaction. A new ten degree-of-freedom potential is developed for use in these calculations. This potential surface is based on a previous potential for C2H2 and C2H as well as previous ab initio calculations of the saddle point properties. We focus on the effect of exciting the symmetric and antisymmetric CH stretches, and symmetric CC stretch in C2H2 on the reactivity, and also on the vibrational distribution of the H2 and C2H products. A significant and surprising finding is that excitation of the CC stretch in combination with excitation of either the symmetric and/or antisymmetric stretch increases the reactivity significantly. A simple Franck–Condon model is used to rationalize these mode specific effects. The thermal rate constant for the H2+C2H→H+C2H2 reaction is also calculated in the temperature range from 200 to 400 K, and compared to limited experimental data. [ABSTRACT FROM AUTHOR]

We present calculations for 40 resonances for nonrotating HCO, using an earlier fit to ab initio calculations of the HCO potential. The method used is a completely L2 approach, augmented by a localized negative imaginary potential which serves as an absorbing boundary in the asymptotic region. The real Hamiltonian is diagonalized in a large basis, using a truncation/recoupling approach, and a subset of the eigenvectors are then used to represent the complex Hamiltonian. This Hamiltonian is diagonalized yielding complex eigenvalues, some of which correspond to resonances. Final rotational distributions of the CO fragment are also calculated for two resonances by a straightforward scattering analysis of the complex L2 wave functions in the near asymptotic region. Comparisons of the new results are made with previous time-independent and time-dependent calculations, and with experiment, including two sets of very recent, preliminary experiments that have determined resonance widths. [ABSTRACT FROM AUTHOR]

We present approximate quantum calculations of cumulative reaction probabilities, rotationally averaged cross sections, and branching ratios for the reactions H+HOD and H+H2O, using the Walch–Dunning–Schatz–Elgersma potential. The calculations are done using the reduced dimensionality, adiabatic-bend approach in which the three internal bending degrees of freedom are treated adiabatically. The H+HOD calculations focus primarily on the effect of vibrationally exciting the OH or OD local modes of HOD on the reactivity, the branching ratios to form the products HD+OH and H2+OD, and their final vibrational state distributions. The calculations of the H+H2O reaction focus on two initial vibrational states, one with three quanta of vibrational excitation in the local mode stretch, and one with two quanta in one local mode and one quantum in the other local mode. The results are generally in good agreement with experiments and previous calculations. [ABSTRACT FROM AUTHOR]

We report reduced dimensionality quantum calculations for zero total angular momentum of the OH+H2H2O+H reaction using the Walch–Dunning–Schatz–Elgersma potential. The three bending degrees of freedom of the tetra-atomic system are treated adiabatically in the harmonic approximation. The full six-mode potential is minimized with respect to the bending degrees of freedom, and the dynamics of the three radial degrees of freedom is governed by an effective potential given by the sum of this minimized potential plus the local adiabatic bending energy. The Schrödinger equation for the radial degrees of freedom is solved using a modification of the hyperspherical approach, which we have described previously. Vibrational state-to-state reaction probabilities are presented for the ground and first excited bending states of H2O. We examine the effect of exciting the vibrations of H2, OH, and H2O on the reaction probability, and the results are compared qualitatively with experiments, and previous calculations. [ABSTRACT FROM AUTHOR]

Thin Cr-Nb-N films with Nb content ranging from 5.1 to 19.5 at.% were prepared onto the AISI 440C substrates by reactive magnetron sputtering of the Cr and Nb in Ar-N 2 gas mixture. The effects of the Nb content on the microstructure and the corrosion behavior in 3.5 wt% NaCl solution were investigated. All the deposited films showed a typical surface feature of granular structure. The Cr-Nb-N films with 5.1 at.% and 10.9 at.% Nb showed a duplex layers consisting of a dense and coherent layer near film-substrate interface, followed by a columnar layer differed from the uniform columnar structure for pure CrN. While for Cr-Nb-N films with higher Nb content, there was no obvious dense layer but a columnar structure. The low Nb content Cr-Nb-N coated samples showed a positive shift of both corrosion potential and the pitting potential compared to the pure CrN coated sample while the pitting potential decreased for high Nb content Cr-Nb-N coated samples. The Cr-Nb-N film with Nb content of 10.9 at.% possesses the best corrosion resistance due to the high polarization resistance resulted from the modification of the microstructure by the Nb incorporation. [ABSTRACT FROM AUTHOR]

The sputtered CrN coatings, which were bombarded by the energetic Cr-ion via filtered arc ion plating layer by layer, were prepared to improve the corrosion resistance of the coated samples. By controlling the times of Cr ion bombardment, the influence of the Cr ion bombarding of the sputtered CrN were investigated from the aspect of the microstructure and corrosion behavior. The results indicated that the CrN film showed a suppressed effect on the coarse columnar structure and a more compact structure with lower porosity by introducing the Cr-ion bombardment. Potentiodynamic polarization curves showed that the CrN coated samples had an obvious improved corrosion resistance after the energetic Cr ion bombardment. With the bombarding times of Cr ion increasing from four to ten, the corrosion resistance of CrN coated samples showed a further improvement with corrosion potential increased about 100 mV and the corrosion current density decreased more than one order of magnitude when compared with the non-bombarded CrN coating. [ABSTRACT FROM AUTHOR]

CrN nanocone-array supported WS 2 film was prepared by depositing a nanocone-array CrN interlayer and then a radio frequency sputtered WS 2 layer. The microstructures of the deposited films were investigated by field emission scanning electron microscopy and grazing incidence X-ray diffraction. The CrN nanocones array have an average period of about 150 nm, and the height of each nanocone is about 100 nm. The CrN nanocone array textured WS 2 film presented an improved lubricating lifetime due to the regular CrN nanocone arrays acting as a good reservoir of the WS 2 lubricates. [ABSTRACT FROM AUTHOR]

Mode selectivity in reactions of hydrogen with deuterated water is studied. (AIP) [ABSTRACT FROM AUTHOR]

Peripheral infections increase the propensity and severity of seizures in susceptible populations. We have previously shown that intraperitoneal injection of a viral mimic, polyinosinic-polycytidylic acid ( PIC), elicits hypersusceptibility of mice to kainic acid ( KA)-induced seizures. This study was undertaken to determine whether this seizure hypersusceptibility entails alterations in glutamate signaling. Female C57 BL/6 mice were intraperitoneally injected with PIC, and after 24 h, glutamate homeostasis in the hippocampus was monitored using the enzyme-based microelectrode arrays. PIC challenge robustly increased the level of resting extracellular glutamate. While pre-synaptic potassium-evoked glutamate release was not affected, glutamate uptake was profoundly impaired and non-vesicular glutamate release was augmented, indicating functional alterations of astrocytes. Electrophysiological examination of hippocampal slices from PIC-challenged mice revealed a several fold increase in the basal synaptic transmission as compared to control slices. PIC challenge also increased the probability of pre-synaptic glutamate release as seen from a reduction of paired-pulse facilitation and synaptic plasticity as seen from an enhancement of long-term potentiation. Altogether, our results implicate a dysregulation of astrocytic glutamate metabolism and an alteration of excitatory synaptic transmission as the underlying mechanism for the development of hippocampal hyperexcitability, and consequently seizure hypersusceptibility following peripheral PIC challenge. [ABSTRACT FROM AUTHOR]

Objective: Some recent studies suggest that multiple miRNAs might regulate neurogenic transdifferentiation of mesenchymal stromal cells (MSCs). In the present study, we hypothesized that the miR-124 can repress the expression of RhoA upon the neurogenesis of adipose derived MSCs (ADMSCs). Methods: MiRNA expression dynamics during neurogenic transdifferentiation of ADMSCs were measured. The expression of neuron-specific enolase (NSE), Tuj-1 (Neuron-specific class III beta-tubulin) and glial fibrillary acidic protein (GFAP), as well as electrophysiological properties, were detected after neurogenic transdifferentiation. The targeting of miR-124 over RhoA was verified by dual luciferase assay, qRT-PCR and western blot. The functions of miR-124 and the RhoA/ROCK signaling pathway were studied using gain and loss of function experiments in vitro. Results: MiR-124 is significantly upregulated during neurogenic transdifferentiation of ADMSCs. Knockdown of endogenous miR-124 hampered neurogenic transdifferentiation and the acquired electrophysiological properties. MiR-124 could directly target RHOA mRNA and repress its expression, through which it increased the proportion of transdifferentiated (transdiff.) cells with positive NSE, Tuj-1 and GFAP. RhoA/ROCK1, but not ROCK2 is a downstream signaling pathway of miR-124 in the process of transdifferentiation. Conclusion: MiR-124 is an important miRNA modulating neurogenic transdifferentiation of ADMSCs at least partly via the miR-124/RhoA/ROCK1 signaling pathway. These findings provided some fundamental information for future use of ADMSCs as an agent for regenerative medicine and cell therapy for neurological diseases. [ABSTRACT FROM AUTHOR]

Previous studies have shown dietary cholesterol can enhance learning but retard memory which may be partly due to increased cholesterol levels in hippocampus and reduced afterhyperpolarization (AHP) amplitude of hippocampal CA1 neurons. This study explored the dose-dependent effect of dietary cholesterol on synaptic plasticity of rabbit hippocampal CA1 neurons and spine morphology, the postsynaptic structures responsible for synaptic plasticity. Field potential recordings revealed a low concentration of dietary cholesterol increased long-term potentiation (LTP) expression while high concentrations produced a pronounced reduction in LTP expression. Dietary cholesterol facilitated basal synaptic transmission but did not influence presynaptic function. DiI staining showed dietary cholesterol induced alterations in dendrite spine morphology characterized by increased mushroom spine density and decreased thin spine density, two kinds of dendritic spines that may be linked to memory consolidation and learning acquisition. Dietary cholesterol also modulated the geometric measures of mushroom spines. Therefore, dietary cholesterol dose-dependently modulated both synaptic plasticity and dendrite spine morphologies of hippocampal CA1 neurons that could mediate learning and memory changes previously seen to result from feeding a cholesterol diet. [ABSTRACT FROM AUTHOR]

Hydrogenated microcrystalline silicon thin films can be used to fabricate stable thin film solar cell, which were deposited by very high frequency plasma-enhanced chemical vapor deposition at low temperatures (~200°C). It has been found that the obtained film presented excellent structural and electrical properties, such as high growth rate and good crystallinity. With the decreasing of silane concentration, the optical gap and the dark conductivity increased, whereas the activation energy decreased. A reasonable explanation was presented to elucidate these phenomena. In addition, we fabricated p-i-n structure solar cells using the optimum microcrystalline silicon thin films, and preliminary efficiency of 4.6% was obtained for 1 μm thick microcrystalline silicon thin film solar cells with open-circuits voltage of 0.773 V and short-circuits current density of 12.28 mA/cm2. Future scope for performance improvement lies mainly in further increasing the short-circuit current. [ABSTRACT FROM AUTHOR]

Abstract: Nanorod structured Si1−x Ge x anodes have been prepared by depositing Si1−x Ge x coatings onto the electrodeposited Ni nanocone arrays for high capacity Li-ion batteries. The obtained samples were characterized by field emission scanning electron microscopy. The electrochemical performance was evaluated by a galvanostatic battery testing. It is found that Si1−x Ge x nanorod displays obvious improved electrochemical performance compared to the pristine film anode. The increase of the Ge content for the Si1−x Ge x anode can improve the capacity retention greatly while retain a rather high capacity. For Si0.71Ge0.29 anode, the charge capacity remains 841mAh/g after 101 cycles, surpassing the Si anode of 662mAh/g. [Copyright &y& Elsevier]

In compressed sensing, the sampling rate can be greatly reduced based on the sparsity of the original signal; however, quantisation is one key aspect in signal acquirement. This article studies the scalar quantisation and its impacts on the compressed sensing. We consider the case in which both the original and the measurement signals are quantised or discrete, which widely exists in the practical applications such as the finite precision signals in the computer and the finite-set original signal in communication systems. We derive the recovery probability bound and the necessary measurement number bound for compressed sensing with scalar quantisation and simulate three modified compressed sensing recovery algorithms. Simulations show that coarse quantisation can be applied in compressed sensing for discrete or quantised sparse signal with sampling and storage efficiency. [ABSTRACT FROM PUBLISHER]

Abstract: Functional Cu nanorods supported P-doped Si anode was designed to improve the performance of lithium-ion batteries for high-power applications. The binder-free anode consists of an electrochemical etched Cu nanorod network coated with P-doped Si. The obtained electrode exhibits excellent rate capability and superior cyclability. At a rate of 2A/g, the anode presents a capacity of 2010mAh/g even after 80 cycles with a capacity retention of above 80%. The anode also presents a stable rate performance even at a high rate of 10A/g. The enhanced performance can be mainly ascribed to the Cu nanorod network which could result in a nanocable structure on the micro-level and play a role of scaffolding on the macro-level, as well as the nature of high conductivity and amorphism of the heavy P-doped Si coating. [Copyright &y& Elsevier]

Objective To determine the protein expression profiles of STAT3 ad its activated form, p - STAT3, in hepatocellular carcinoma ( ??? ) and investigate the potential clinica significance. Methods The expressions of STAT3 ad p - STAT3 were detected in 90 ??? tissues ad patient - matched cancer - adjacent healthy tissues by immunohistochemistry. The significance of between - tissue differences in protein expression was assessed by Gii - squared test. The relations of significant diferential expression with patients' clinicopathological features ad prognoses ( based on 5 - year follow - up) were assessed by ?? regression models. Five - yea survival rates were determined by Kaplan - Meier aalysis with Log - rak test. Results In ??? tissues, STAT3 was manly detected in the cytoplasm ad p - STAT3 was manly detected in the nucleus. The levels of both STAT3 and p - STAT3 were significatly higher in ??? than in addacent non - cacer tissues. There was no significat relation for either STAT3 or p - STAT3 protein expression with sateHite lesions, vascular invasion, ??? stage of disease progression, sex, age, tumor size, tumor number, degree of diferentiation, or alpha - fetoprotein expression. The 5 - yea survival rate of patients with high expressions of STAT3 and p - STAT3 in ??? tissues was significantly lower than patients with low expression. Conclusion STAT3 ad p - STAT3 protein may contribute to the invasive and metastatic qualities of ???, ad represent a useful new prognosis reference index of this liver cacer. [ABSTRACT FROM AUTHOR]

Abstract: A CuO nanostructure was prepared on copper plate by a simple electrochemical etching and a subsequent heat treatment instead of the commonly used solution-immersion method. The architecture was used as anode of lithium ion batteries without any conductive binder. Excellent rate capability and improved cyclability were obtained with a specific capacity of 740mAh/g upto 50 cycles at a rate of 100mA/g. The improved performance can be attributed to the quasi-1-dimensional nanostructure prepared directly on the current-collecting copper plate, which offers good strain accommodation, short electron/lithium ion transport path and excellent electrical contact between active material and current-collector. [Copyright &y& Elsevier]

The Al doping stability of p-type SiC has always been a difficult problem in the growth of p-type SiC. In this study, a novel Al doping method was used to grow p-type SiC. p-Type 4H-SiC crystals were grown by a physical vapor transport (PVT) method using p-type SiC powder. p-Type SiC powder was synthesized by a self-propagating high-temperature synthesis method. The powder was observed under an optical microscope. Raman and XRD analysis results demonstrated that the synthesized SiC powder was mainly a 3C-SiC polytype. The Al content and binding mode of the p-type SiC powder were characterized by EDS and XPS, respectively. In addition, the differences between using p-type SiC powder and direct Al compound doping in the SiC powder region to grow p-type SiC crystals were studied. Results showed that the continuity of Al element doping using p-type SiC powder was much better than the doping method of placing an Al compound in the SiC powder region. Moreover, the utilization rate of the Al element was greatly increased. The resistivity of the crystal grown by the p-type SiC powder method was reduced by about 5 times. And the axial resistivity uniformity was also improved by the p-type SiC powder method. [ABSTRACT FROM AUTHOR]

We evaluated the effect of Jiaji electroacupuncture on cell proliferation and the expression of markers of endogenous neural stem cell activation after complete spinal cord transection. Female Wistar rats were assigned to 4 groups ( n = 24 each): a sham-operated group, a control group, a Jiaji electroacupuncture group, and a Jiaji electroacupuncture preconditioning group. Motor function was significantly improved in the acupuncture groups compared to the control group at 7 and 14 d. Numbers of bromodeoxyuridine (BrdU)-, nestin-, and glial fibrillary acidic protein (GFAP)-positive cells were significantly greater in the acupuncture groups than in the controls at each time point. Expression of nestin and GFAP mRNA was significantly higher in the acupuncture groups than in the controls at each time point. Thus, Jiaji electroacupuncture and preconditioning may promote the proliferation of endogenous neural stem cells after spinal cord transection. [ABSTRACT FROM AUTHOR]

Abstract: Hydrogenated nanocrystalline Si (nc-Si:H) nanorod arrays were cost-effectively prepared on electrodeposited nickel nanocones substrates by very high frequency plasma enhanced vapor deposition. The antireflection properties of the obtained Si nanorod arrays were investigated carefully for the possible application in solar cells. It was found that the structures of nc-Si:H nanorod arrays can be tuned to obtain a very low reflectance especially in the near infrared region. The obtained Si nanostructure with well-separated nanorods, each of which had an average diameter of 200nm and height of 700nm, showed a reflectance value of <5% at normal incident over a wide wavelength of 400–1100nm. [Copyright &y& Elsevier]

Abstract: A series of nc-Si:H films with different crystalline volume fractions have been deposited by very high frequency glow discharge in a plasma with a silane concentration [SiH4]/([SiH4]+[H2]) varying from 2% to 10%. The nc-Si:H films have been characterized by Raman spectroscopy, XRD diffraction, and UV–vis–near infrared spectrophotometer. The deposition rate increases nearly linear with increasing the silane concentration while the crystalline volume fraction decrease from 58% to 12%. The refractive index and the absorption of the samples were obtained through a modified four-layer-medium transmission model based on the envelope method. It was found that the refractive indices and absorption coefficient increase with increasing silane concentration. Compared to the films deposited using conventional RF-PECVD with excitation frequency of 13.56MHz, the samples prepared by very high frequency glow discharge have higher absorption coefficients, which is due to its better compactness and lower defect density. [Copyright &y& Elsevier]

Na/H exchanger 1 (NHE1), a regulator of intracellular pH (pHi), plays a significant role in regulating tumor cell growth and apoptosis. In the present study, we determined its role in hepatocellular carcinoma (HCC). Immunohistochemistry was carried out to detect NHE1 expression in HCC tissue for the correlation of NHE1 with clinicopathological data from patients. NHE1-siRNA and 5- (N-ethyl-N-isopropyl) amiloride (EIPA, highly specific inhibitor of NHE1) were used to assess the function of NHE1 in HCC cells by using gene transfection, methyl thiazolyl tetrazolium (MTT), flow cytometry, and nude mouse xenograft assays as well as fluorescence spectroscopy. We found that NHE1 expression was increased in HCC tissues and cells in which its expression was associated with the increased tumor size, venous invasion and advanced tumor stages. However, suppression of NHE1 expression by using NHE1-siRNA and EIPA reduced growth, but induced apoptosis of HCC cells. EIPA also inhibited tumor growth in nude mouse xenografts of HCC cells. The data from our current study demonstrates that NHE1 was overexpressed in HCC and that inhibition of NHE1 could be a potential therapeutic target for HCC. [ABSTRACT FROM AUTHOR]

Abstract: In addition to pharmacological treatment of ischemic stroke, hypothermia has been proposed to be a therapeutic option for protecting brain cells from ischemic death. Less is known about the molecular mechanisms underlying this hypothermic protection of ischemic cells, which we have investigated in rats. In four groups of experiments, ischemia under the conditions of normothermia and mild hypothermia as well as sham-operation under these two conditions, we have analyzed quantitatively the score of neurological impairment and the expression of second mitochondrion -derived activator of caspases (SMAC), an index of cellular apoptosis. Compared with ischemia under normothermia, the treatment of mild hypothermia significantly improves brain function and lowers SMAC expression. Our results indicate that the mild hypothermia protects the functions of brain cells from ischemic impairment through attenuating apoptotic death. [ABSTRACT FROM AUTHOR]

Abstract: Hydrogenated microcrystalline silicon films have been prepared by plasma-enhanced chemical vapor deposition technique using silane diluted in H2 or H2 +Ar. The microstructures for silicon films have been evaluated by Raman scattering spectroscopy, X-ray diffraction and Fourier-transform infrared spectroscopy. Optical characterization has been done by UV–vis spectroscopy. It is found that the addition of Ar in diluent gases efficiently improves the deposition rate and crystallinity due to an enhanced dissociation of the source gas and the energy of deexcitation of Ar* released within the growth zone. Meanwhile, the enhanced crystallinity and the reducing of hydrogen ion bombardment with increasing Ar dilution lead to the polymerization and also a bad passivation of the hydrogen which cause the widening of the optical gap and increase of defect states in the μc-Si films. The absorption coefficient and dark conductivity are found to decrease basically with increasing Ar dilution corresponding to the widening optical gap and more defects. That the activation energy increases with increasing Ar dilution or decreasing hydrogen dilution is due to the fact that more defect states lead to a pulling down of the Fermi level. [ABSTRACT FROM AUTHOR]

Abstract: Na+/H+ exchanger 1 (NHE1) plays a significant role in tumor metastasis. However, the exact mechanisms by which NHE1 mediates cell invasion and migration, especially in hepatocellular carcinoma (HCC), are not yet known. In the current study, we show for the first time that the inhibition of NHE1 by 5-(N-ethyl-N-isopropyl) amiloride (EIPA) is able to suppress migration and invasion of HepG2 cells under hypoxic conditions. In addition, hypoxia activated ERK1/2, which in turn promoted the production of MMP-2, MMP-9 and VEGF. EIPA’s suppressive role was determined to act through down-regulation of MMP-2, MMP-9 and VEGF in an ERK1/2 dependent manner. The data demonstrate that NHE1 plays a role in HCC invasion and that NHE1 may be a potential therapeutic target for HCC treatment. [Copyright &y& Elsevier]

Abstract: Previous work has shown high dietary cholesterol can affect learning and memory including rabbit eyeblink conditioning and this effect may be due to increased membrane cholesterol and enhanced hippocampal amyloid beta production. This study investigated whether dietary cholesterol modulates rabbit hippocampal CA1 neuron membrane properties known to be involved in rabbit eyeblink conditioning. Whole-cell current clamp recordings in hippocampal neurons from rabbits fed 2% cholesterol or normal chow for 8 weeks revealed changes including decreased after-hyperpolarization amplitudes (AHPs) – an index of membrane excitability shown to be important for rabbit eyeblink conditioning. This index was reversed by adding copper to drinking water – a dietary manipulation that can retard rabbit eyeblink conditioning. Evidence of cholesterol effects on membrane excitability was provided by application of methyl-β-cyclodextrin, a compound that reduces membrane cholesterol, which increased the excitability of hippocampal CA1 neurons. [Copyright &y& Elsevier]

Hyperspherical harmonics for triatomic systems as functions ofrow-orthonormal hyperspherical coordinates, (also called democratichyperspherical harmonics) are obtained explicitly in terms of Jacobipolynomials and trigonometeric functions. These harmonics are regularat the poles of the triatomic kinetic energy operator, are complete,and are not highly oscillatory. They constitute an excellent basisset for calculating the local hyperspherical surface functions inthe strong interaction region of nuclear configuration space. Thisbasis set is, in addition, numerically very efficient and should permitbenchmark-quality calculations of state-to-state differential andintegral cross sections for those systems. The approach used for theirderivation is new and should be applicable to systems of more thanthree atoms. [ABSTRACT FROM AUTHOR]

Abstract: This paper provides a convergence analysis of a fractional-step method for time-dependent system of equations of linear elasticity by means of finite element approximations. Error estimates in finite time are given. And it is verified that provided the time-step is sufficiently small, the proposed algorithm yields for finite time an error of in the -norm for the displacement field and an error estimate of in the -norm, where is the mesh size. In addition, under stronger initial conditions we obtain an error estimate of in the -norm for the divergence field . [Copyright &y& Elsevier]

The easy oxidation and poor corrosion resistance of the sputtered WS 2 film would limit its application in spacecraft due to the sharp deterioration of lubricity resulting from the contact with the marine atmosphere inevitably with the increasing space launch from sea or seaside. In this study, the active metal Ta was skillfully introduced into the WS 2 film through co-sputtering of the WS 2 and Ta targets. The influence of the doped Ta related microstructure regulation on the tribological and anti-corrosion properties of the prepared composite films was investigated. It showed that the incorporation of the active Ta would activate the residual O atoms to form Ta 2 O 5 phase while making the WS 2 phase partly oxidized to form the WS x O y and WO 3. WS 2 –Ta composite films with low Ta content exhibited low friction coefficient and long wear life more than 3 times of that for pure WS 2 film. In addition, the corrosion resistance of WS 2 –Ta film was improved by a positive shift of corrosion potential in salt spray with increasing the Ta content, originating from the passivation effect of the Ta 2 O 5 phase and the WS x O y phase in the film as well as the dense structure. • WS 2 –Ta composite films with different Ta contents were prepared by magnetron sputtering system. • The incorporation of the much active Ta would activate the residual O atoms to form the Ta 2 O 5 and partly WS x O y. phase. • WS 2 –Ta composite film exhibited significantly improved tribological property and corrosion resistance. [ABSTRACT FROM AUTHOR]