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As an important part of a modern economic system, a modern industrial system is the key to promoting high-quality economic development. China's modern industrial system construction focuses on industrial restructuring. At present, in order to strengthen the support and leading role of transportation in the modern economic system, China is actively promoting the construction of a competitive transportation power. Therefore, it is necessary to study whether large-scale investment in transportation infrastructure can promote industrial structure transformation and upgrade. This paper takes China as the research background. Firstly, a RAM model was employed to evaluate the unified economic and environmental efficiency of transportation infrastructure that measures the level of transportation infrastructure investment. Secondly, a PVAR model was built to evaluate the dynamic effects of transportation infrastructure investment on industrial structure transformation and upgrade. Finally, from the perspective of rational flow and optimal allocation of resource factors, the paper points out that transportation infrastructure investment can indirectly promote industrial structure transformation and upgrade through three paths, namely expanding market demand, reducing resource misallocation and increasing technological innovation, and the first half of these paths are positively regulated by policies. Then, an empirical test was done with the moderated mediation model. Research findings suggest that: first, improvements in the unified economic and environmental efficiency of transportation infrastructure can only promote industrial structure supererogation in a short time, but have no significant effect on promoting industrial structure rationalization in the short or long term. Second, in actual situation, transportation infrastructure investment can promote industrial structure transformation and upgrade only by expanding market demand and technological innovation, but not by reducing resource misallocation. Third, the first half of these paths through which transportation infrastructure investment promotes industrial structure transformation and upgrade are positively regulated by policies. This paper provided some theoretical reference for promoting industrial structure transformation and upgrade by virtue of the sustainable development of transportation. [ABSTRACT FROM AUTHOR]

The ethanol oxidation reaction (EOR) is an ideal alternative to the oxygen evolution reaction (OER) towards energy efficient hydrogen production. Here, the chrysanthemum-shaped B doped cobalt-nickel bimetallic phosphide with heterogeneous structure grown on nickel foam (B-Ni 2 P/CoP/NF) are synthesized and can act as a high activity bifunctional electrocatalysts for both the hydrogen evolution reaction (HER) and EOR. In 1.0 M KOH, the obtained catalyst shows good activity and excellent long-term stability (no decay after 108 h) for HER, with an overpotential of only 33 mV (vs. RHE) to reach a current density of 10 mA cm−2. The calculation of turnover frequency (TOF) and transfer coefficient (β) prove that the catalyst has good intrinsic catalytic activity, For EOR, in 1.0 M KOH+1.0 M C 2 H 5 OH solution, the B-Ni 2 P/CoP/NF catalyst requires only 1.45 V (vs. RHE) oxidation potential to reach the current density of 50 mA cm−2, which is 270 mV less than OER. Using B-Ni 2 P/CoP/NF as a bifunctional catalyst, the current density of 20 mA cm−2 can be achieved with only 1.48 V cell voltage in 1.0 M KOH+ 1.0 M C 2 H 5 OH solution, which is remarkably lower than the required cell voltage of water electrolysis (1.63 V) to achieve the same current density. This study demonstrates an efficient bimetallic phosphide as earth-abundant bifunctional electrocatalysts for green hydrogen production coupled with electrolysis of ethanol. [Display omitted] • The chrysanthemum-shaped B-CoP/Ni 2 P/NF catalyst with heterogeneous structure is prepared. • The B-CoP/Ni 2 P/NF catalyst has excellent bifunctional catalytic activity toward EOR and HER.in alkaline solution. • The doping of B regulates the electronic structure and further strengthens the synergistic effect of metal Ni and Co. [ABSTRACT FROM AUTHOR]

The development of renewable clean energy is imminent as global warming and environmental pollution become more serious issues today. Hydrogen energy has been widely studied as an ideal green energy source. Among several common hydrogen production methods, hydrogen production by electrolysis of water is considered an efficient, environmentally friendly, and sustainable hydrogen production strategy. Transition metal phosphates have outstanding electrocatalytic conductivity and high catalytic efficiency, thus exhibiting catalytic effects similar to noble metals. To further enhance the catalytic activity of the transition metal phosphates, in this paper, the cauliflower-like Co-W-P-O 4 /NF catalyst based on three-dimensional nickel foam was prepared by the method of element doping. The catalyst exhibited good bifunctional catalytic activity in alkaline solution. The prepared Co-W-P-O 4 /NF has a unique crystalline-amorphous phase structure with abundant active sites at the interface. In addition, W atoms can interact with Co atoms to co-optimise the electronic structure, enabling the Gibbs free energy of hydrogen adsorption (ΔG H*) to be close to 0, which is conducive to improving the performance of water electrolysis. To achieve a current density of 10 mA·cm−2, the Co-W-P-O 4 /NF required overpotentials of 42.1 mV for HER and 348.2 mV for OER in 1 M KOH solution, with the Tafel slopes being 48.0 and 83.6 mV·dec−1, respectively. When Co-W-P-O 4 /NF was used as both cathode and anode for water splitting, the two-electrode electrolyzer could achieve 10 mA·cm−2 with only 1.62 V, along with good stability. [Display omitted] • The cauliflower-like Co-W-P-O 4 /NF with crystalline-amorphous phase structure is prepared. • Co-W-P-O 4 /NF catalyst shows good bifunctional catalytic activity in alkaline solution. • The electron rearrangement and the rough surface structure can improve the performance of catalyst. [ABSTRACT FROM AUTHOR]

With the process node further scaling down, the bit cell of magnetic random access memory (MRAM) device suffers from severe failure and reliability problems due to its process variation. In this article, we explored the variability of a promising toggle spin torques MRAM (TST-MRAM) in detail, which achieves ultrafast switching speed and high endurance and is expected to be applied as upper-level caches. Our research is conducted with a 14 nm FinFET design kit, the basic performance of TST-MRAM and different pulse conditions are explored, and then the variation effect of device parameters is discussed and compared in detail as well as the write error rate (WER) under different voltages. The results demonstrate that the variation of access transistors dominates the variability, where the transistor in the spin–orbit torque (SOT) branch has a greater negative impact than the transistor in the spin transfer torque (STT) branch. To further reduce WER, a better structure with diodes of bit cell is proposed. [ABSTRACT FROM AUTHOR]

In order to improve the diagnosis accuracies of the current diagnosis methods, a novel fault diagnosis method of automobile gearbox based on novel successive variational mode decomposition and weighted regularized extreme learning machine is presented for fault diagnosis of gearbox in this paper. The novel successive variational mode decomposition (SVMD) is presented to improve the traditional variational mode decomposition, which finds modes one after the other, and this succession helps increase convergence rate and also not extract the unwanted modes; weighted regularized extreme learning machine (WRELM) is presented to improve the traditional extreme learning machine, which uses the weight of each sample with the nonparametric kernel density estimation and can find the optimal weight for each sample. The test results indicate that the diagnosis accuracy of SVMD-WRELM for gearbox is better than that of VMD-WRELM, VMD-ELM. [ABSTRACT FROM AUTHOR]

In this paper, we have studied the impact of quantum confinement on the performance of n-type silicon nanowire transistors (NWTs) for application in advanced CMOS technologies. The 3-D drift-diffusion simulations based on the density gradient approach that has been calibrated with respect to the solution of the Schrödinger equation in 2-D cross sections along the direction of the transport are presented. The simulated NWTs have cross sections and dimensional characteristics representative of the transistors expected at a 7-nm CMOS technology. Different gate lengths, cross-sectional shapes, spacer thicknesses, and doping steepness were considered. We have studied the impact of the quantum corrections on the gate capacitance, mobile charge in the channel, drain-induced barrier lowering, and subthreshold slope. The mobile charge to gate capacitance ratio, which is an indicator of the intrinsic speed of the NWTs, is also investigated. We have also estimated the optimal gate length for different NWT design conditions. [ABSTRACT FROM PUBLISHER]

Background: The principal objective of this study was to gain a better understanding of the mechanisms of type 2 diabetes mellitus (T2DM) patients with fatigue (D-T2DM) through exome and transcriptome sequencing. Methods: After whole-exome sequencing on peripheral blood of 6 D-T2DM patients, the consensus mutations were screen out and analyzed by a series of bioinformatics analyses. Then, we combined whole-exome sequencing and transcriptome sequencing results to find the important genes that changed at both the DNA and RNA levels. Results: The results showed that a total of 265,393 mutation sites were found in D-T2DM patients compared with normal individuals, 235 of which were consensus mutations shared with D-T2DM patients. These genes significantly enriched in HIF-1 signaling pathway and sphingolipid signaling pathway. At the RNA level, a total of 375 genes were identified to be differentially expressed. After the DNA-RNA joint analysis, eight genes were screened that changed at both DNA and RNA levels. Among these genes, FUS and LMNA were related to carbohydrate metabolism, energy metabolism, and mitochondrial function. Subsequently, we predicted the herbs, including Qin Pi and Hei Zhi Ma, that might play a therapeutic role in D-T2DM through the SymMap database. Conclusion: These findings have significant implications for understanding the mechanisms of D-T2DM and provide potential targets for D-T2DM diagnosis and treatment. [ABSTRACT FROM AUTHOR]

A magnetic tunneling junction (MTJ) with very low energy barrier, which shows controllable stochastic property, is recently proposed to constitute the probability bit (P-Bit). With the P-Bit, Ising computation, which is a general and powerful computing platform for both conventional and non-conventional problems, is implemented. However, such hardware emulation suffers from the severe intrinsic variations of a stochastic MTJ device. The nonuniform probability switching curves of different stochastic MTJs hinder straightforward expansion of Ising computer to a large P-Bits array for solving more complicated problems. In this work, we propose a novel Ising computer using a single stochastic MTJ device. With the utilization of the time-division multiplexing (TDM) technology, a “Compute–Read–Switch” scheme is proposed, so that the single stochastic MTJ can act as multiple P-Bits during Ising computation. A design guide for the current magnitude and time duration of the “Compute–Read–Switch” scheme is investigated and provided. Furthermore, NOT and XOR logic gates are implemented with our proposal. An accuracy rate as high as 69% for the integer factorization is also achieved, which is comparable with conventional Ising computer. Meanwhile, the TDM Ising computer avoids the calibration process, which is mandatory in the conventional Ising computer. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the usefulness of Contrast-enhanced ultrasound (CEUS) in the diagnosis and differential diagnosis of Polypoid lesions of gallbladder (PLGs) ≥ 1 cm.Methods: A prospective analysis was performed on 180 patients with PLGs ≥ 1 cm. 175 cases were confirmed by pathological diagnosis and the remaining were confirmed by other imaging findings. The characteristics of lesions on conventional Ultrasonography (US) and CEUS were recorded.Results: Significant differences were observed in enhancement patterns between benign and malignant PLGs during both arterial (P < 0.001) and venous phases (P < 0.001). The malignant lesions typically yielded a "fast-in and fast-out" enhancement pattern. There was no significant difference in Arrival time (AT) between malignant and benign PLGs. If we consider wash-out time ≤ 40 s as a diagnostic standard for malignant lesions, the sensitivity, specificity, and accuracy were 88.24%, 85.62%, and 86.11%, respectively. Destruction of the Gallbladder (GB) wall was a particularly important indication of malignant PLGs, and the sensitivity, specificity, and accuracy were 93.33%, 92.12%, and 92.22%, respectively. The accuracy of CEUS in the diagnosis of PLGs, as well as malignant and benign lesions, was 92.22%, 92.47%, and 91.17%, respectively.Conclusions: The "fast-in and fast-out" enhancement pattern, hyper-enhancement in comparison to the GB wall in the arterial phase, wash-out time ≤ 40 s, GB wall destruction, and hepatic parenchymal infiltration are the characteristic findings of malignant PLGs. Besides, CEUS provides a valuable reference to classify some of the benign lesions. [ABSTRACT FROM AUTHOR]

Climbing dunes are a form of topographic barrier dunes that feature in the aeolian landforms on the Qinghai-Tibetan Plateau. Topography fundamentally influences the spatial distribution and morphological characteristics of climbing dunes by modifying the near-surface airflow and creating space for sediment deposition. Previous studies have considered several aspects of the influence of topography on aeolian landforms. However, morphological differences between climbing dunes in different geomorphic contexts and dynamic changes in the area have received little attention. Therefore, topographic measurements, near-surface flow field measurements, dune morphology analysis, and remote sensing image analysis were combined to explore relationships between dune morphology and topography. Topographic obstacles can accelerate the near-surface airflow, particularly with a 25–35° slope gradient, which is beneficial for sand transport and deposition. Suitable accommodation space (concave slope morphology) and abundant sediment comprise the primary factors that control the scale and morphological diversity of climbing dunes, which are also influenced by a variable wind direction. In general, the morphology of the climbing dunes becomes progressively more complicated from the bottom to the middle of the windward slope, and the sand ridge lines of the dunes are perpendicular to the prevailing wind direction. Based on the influence of climate and human activities, the total area of climbing dunes in this region has decreased over the past 30 years. Despite general evidence of enhanced human-induced desertification in semi-arid and sub-humid regions, warming has not led to the rapid expansion of climbing dunes in these arid locations. This research offers new insights into the relationship between the terrain and dune morphology, enriching the theoretical basis for the plateau aeolian geomorphology. Furthermore, it allows us to consider the dynamic changes in climbing dunes area in the context of global warming. • Clarify the relationship between terrain, near-surface airflow and dune morphology • Sand sources and slope morphology are controlling the scale of climbing dune. • Analysis of the dynamic changes of climbing dune under climate warming [ABSTRACT FROM AUTHOR]

Spin-transfer torque magnetic random access memory (STT-MRAM) offers nonvolatility, good scalability, high speed, and low-power benefits. Multilevel cell (MLC) is an efficient technology to boost the storage density of the STT-MRAM. However, the conventional MLC structure is not suitable for more than 2-b storage due to inefficient multistep read/write operations. In this article, combining the emerging spin-orbit torque (SOT) and STT mechanisms, we propose a novel STT/SOT hybrid triple-level cell (TLC) MRAM cell structure. Corresponding write and read schemes are designed for this hybrid bit-cell to achieve low-cost operations. Unlike the regular stacked TLC, 3-b data can be written in two steps in the proposed cell structure, and be read in parallel with the assistance of SOT. Simulation results show that the proposed structure achieves 32% and 43% savings on write delay and energy consumption, respectively. Monte Carlo statistic simulation results indicate 1.4 × improvement in sensing margin as well. [ABSTRACT FROM AUTHOR]

Wear-resistant films, which are widely applied to extend the service life of the gears and bearings, usually surfer from dynamic bonding fatigue failure induced by the Hertz-like contact. However, there is still lack of research on the influence of the main mechanical parameters of films on the dynamic bonding fatigue failure mechanism. In this work, graphite-like carbon (GLC) films with a low friction coefficient and different Ti doping ratios were deposited on the surface of stainless steel via direct current magnetron sputtering (DCMS) technology. The microstructure and mechanical properties of the films before and after vacuum annealing were investigated by SEM, Raman, and nanoindentation, and the dynamic bonding failure life of the films were evaluated by the ball-bearing-disc method with dynamic contact fatigue loads. The results revealed that the critical dynamic bonding strength exhibited a significant function dependence on the values of hardness-to-elastic modulus (H3/E2) parameters of the GLC films. The film failure mechanism showed a transition from the film/substrate interface spalling mode to the near-surface cohesion shear spalling mode with the increase of H3/E2. [Display omitted] • GLC films with low friction coefficient and different Ti doping ratios were deposited on stainless steel. • Vacuum annealing treatment leads to changes in the mechanical properties and carbon phase. • The increase of H3/E2 ratio can significantly enhance fatigue life and change the failure behaviours of the GLC films. • The reasons for the difference in failure mechanisms of films at dynamic bonding fatigue strength test were analysed. [ABSTRACT FROM AUTHOR]

Climbing-falling dunes system plays an important role in aeolian landforms and has the potential to provide rich environment evolution information in arid and semi-arid regions. However, there are relatively few researches on distribution pattern and classification of climbing-falling dunes system in the Qinghai-Tibet Plateau. This study provides a data-rich examination of the distribution rule of duns system. The location, geological characteristics, underlying topography, type, climbing height, orientation, distance between dunes and rivers of 689 climbing-falling dunes are recorded based on the Google Earth image. The total area covered by climbing-falling dunes in the Qinghai-Tibet Plateau is about 8328km2, which represents 2.8% of the total area of aeolian landforms in the plateau, and 0.03% of the entire plateau area. The climbing-falling dunes were densely distributed in Qaidam Basin, Gonghe Basin, Kumkol Basin, foothills of Qilian Mountains, foothills of the Altun Mountains, the Southern Tibet Valley and the source area of Yellow River and Yangtze River. The dunes mainly cover the piedmont alluvial fan, concave slope, denuded monadnock, river terraces, wide valleys, the bend of the river and the foothills around lakes and reservoirs. The average height of climbing-falling dunes in the Plateau was 216m, with the maximum and minimum climbing height being 1416m and 2m, respectively. The climbing-falling dunes in the Qinghai-Tibet Plateau mainly distributed in 10 watersheds, the duns are within 4km of the nearest channel and 21km of the main channel and mainly vertical to the rivers flow. According to digital elevation models, the climbing-falling dunes are densely distributed in the range of 0-45 degrees in slope and 3000-4500m in elevation, dunes mainly on the north/shady slope, followed by the south/sunny slope. Dunes of the internal flow area are on the shady slope, while the outflow are on the sunny slope. The types of dunes at higher elevations are simple, while those at lower elevations are complex. Field investigation and database are used to determine the classification of the climbing-falling dunes, we think the climbing-falling dunes are distributed in piedmont zone, river valley regions, the surrounding of lake and reservoirs. The underlying landforms of climbing-falling dunes distribution are divided into the six categories: piedmont sediment, denuded monadnocks, bedrock, fluvial sediment, bedrock and alluvial deposits, ancient dunes. [ABSTRACT FROM AUTHOR]