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Abstract Two-dimensional (2-D) semiconductors have been intensely explored as alternative channel materials for future generation ultra-scaled transistor technology [1–8]. However, significant roadblocks (e.g., poor carrier mobilities [9–11] , instability [4,5,10], and vague potential in scaling-up [10,12–15]) exist that prevent the realization of the current state-of-the-art 2-D materials' potential for energy-efficient electronics. The emergent solution-grown tellurene exhibits attractive attributes, e.g., high room-temperature mobility, large on-state current density, air-stability, and tunable material properties through a low-cost, scalable process, to tackle these challenges [16]. Nevertheless, the fundamental manufacturing science of the hydrothermal processing for tellurene remains elusive. Here, we report on the first systematic, data-driven learning of the process-structure-property relationship in solution-grown tellurene, revealing the process factors' effects on tellurene's production yield, dimensions, and transistor-relevant properties, through a holistic approach integrating both the experimental explorations and data analytics. We further demonstrate the application of such fundamental knowledge for developing tellurene transistors with optimized and reliable performance, which can enable the cost-effective realization of high-speed, energy-efficient electronics. Graphical abstract The fundamental solution-growth mechanism for 2-D tellurene has been revealed through a sophisticated data-driven, probabilistic learning framework for nanomanufacturing high performance nanoelectronics. fx1 Highlights • The growth mechanism for tellurene was learnt via a data-driven framework. • A learning-optimization cycle was demonstrated for nanomanufacturing tellurene. • The learnt knowledge was used to develop high-performance tellurene transistors. [ABSTRACT FROM AUTHOR]

A two-dimensional numerical approach has been proposed in this article to help with the simulation and visualization of dynamic de-icing process, thereby facilitating a better understanding of the pertinent physical phenomena involved in the ice melting process for cold-climate wind turbines. In this method, Reynolds-averaged Navier-Stokes equations and Shear Stress Transport k-ω turbulence model are adopted to calculate the outer fluid velocity field, and a two-step apparent heat capacity method has been employed to simulate the inner phase change. Corresponding field de-icing experiments on a 2 kW wind turbine have been performed at a natural icing station to provide essential parameters and subsequent validation for the simulation. The results show that the simulations are in good consistence with experiments. The relative errors between predicted actuation durations and measured ones are in acceptable range. Through comprehensive analysis of both numerical and experimental results, the wind turbine dynamic de-icing process has been explored. It is revealed that the de-icing process of wind turbine blades is mainly consisted of four distinct periods, i.e. sharp and short temperature-rising period, plateau period, gentle and long temperature-rising period, and fluctuation period (if exists). The mechanism of the generation of each stage has also been elucidated. [ABSTRACT FROM AUTHOR]

Rapid uncontrolled leg penetration, or punch-through, accounts for a substantial number of accidents related to jack-up platforms, which are typically only employed at any one site for a few months before being removed and installed elsewhere. Hence, the ability to predict the load–penetration curve of a spudcan footing is particularly important in layered soil profiles, in order to identify punch-through risk prior to mobilisation of the rig. The correlation method proposed here links the spudcan load–penetration curve directly to the profile of cone tip resistance that is typically obtained as part of an offshore site investigation campaign. This contrasts with existing approaches that require input parameters that are empirically derived from site investigation measurements or necessitate additional soil element testing in an onshore laboratory. [ABSTRACT FROM AUTHOR]

A numerical technique for modeling the soil as a two-phase medium by means of a user material subroutine is presented. The approach is applied to a classical FE analysis in a Lagrangian formulation using an explicit time integration rule and to a Coupled Eulerian–Lagrangian approach. The application of these two approaches to the problem of pile jacking into fully saturated soil under partially drained conditions is investigated and compared to the solution obtained by use of an iterative equation solver. The influence of the installation process as well as the influence of the permeability on the surrounding soil is investigated. [ABSTRACT FROM AUTHOR]

• Explore the influence of wind process time scale on wind speed fluctuation law. • Propose wind speed forecasting model utilize time scale information of wind process. • Adopt complex network to mining the morphological characteristic of wind curve. The forecast of wind speed is prerequisite for wind power prediction, which is one of the most effective means of promoting wind power absorption. However, when modeling for wind speed sequences with different fluctuations, most existing researches ignore the influence of time scale of wind speed fluctuation period, let alone the low compatibility between training and testing samples that severely limit the training performance of forecasting model. To improve the accuracy of wind speed and wind power forecasting, an ultra-short-term wind speed forecasting model based on time scale recognition and dynamic adaptive modeling is proposed in this paper. First, a series of wind processes are divided from the historical wind speed sequence according to the natural variation characteristics of wind speed. Second, we divide all the wind processes into two patterns based on their time scale, and an SVC model with input features extracted from meteorological data is built to identify the time scale of the current wind process. Third, for a specifically identified wind process, the complex network algorithm is applied in data screening to select high compatible training samples to train the forecast model dynamically for current input. Simulation indicates that the proposed approach presents higher accuracy than benchmark models using the same forecasting algorithms but without considering the time scale and data screening. [ABSTRACT FROM AUTHOR]

Abstract: The vanadium redox flow battery (VRFB) has emerged as a viable grid-scale energy storage technology that offers cost-effective energy storage solutions for renewable energy applications. In this paper, a novel methodology is introduced for modeling of the transport mechanisms of electrolyte flow, species and charge in the VRFB at the pore scale of the electrodes; that is, at the level where individual carbon fiber geometry and electrolyte flow are directly resolved. The detailed geometry of the electrode is obtained using X-ray computed tomography (XCT) and calibrated against experimentally determined pore-scale characteristics (e.g., pore and fiber diameter, porosity, and surface area). The processed XCT data is then used as geometry input for modeling of the electrochemical processes in the VRFB. The flow of electrolyte through the pore space is modeled using the lattice Boltzmann method (LBM) while the finite volume method (FVM) is used to solve the coupled species and charge transport and predict the performance of the VRFB under various conditions. An electrochemical model using the Butler–Volmer equations is used to provide species and charge coupling at the surfaces of the carbon fibers. Results are obtained for the cell potential distribution, as well as local concentration, overpotential and current density profiles under galvanostatic discharge conditions. The cell performance is investigated as a function of the electrolyte flow rate and external drawing current. The model developed here provides a useful tool for building the structure–property–performance relationship of VRFB electrodes. [Copyright &y& Elsevier]

Abstract: Offshore jack-up rigs are often used for site exploration and oil well drilling. The footings of jack-up rigs are known as spudcan foundations. The risk of rapid uncontrolled penetration of spudcan in seabed (“punch-through”) exposes jack-ups to significant risk during installation in strong over weak layered seabeds. An example for this is a thin loose sand layer overlying a weaker stratum of clay. To prevent spudcans from “punch-through”, an in-situ measurement concept is suggested in this paper to control the installation process of spudcan foundations. First, three-dimensional finite element studies using a Coupled Eulerian–Lagrangian method are carried out to simulate the penetration process. The numerical results have been validated with existing analytical solutions and centrifuge model test data. Furthermore, parametric studies are carried out to quantify the influences of the sand thickness and shear strength of the clay on the bearing capacity of spudcans. Based on the numerical studies an idea for the development of an in-situ measurement concept is suggested to control the spudcan penetration process in-situ. [Copyright &y& Elsevier]

Abstract: Geotechnical boundary value problems involving large deformations are often difficult to solve using the classical finite element method. Large mesh distortions and contact problems can occur due to the large deformations such that a convergent solution cannot be achieved. Since Abaqus, Version 6.8, a new Coupled Eulerian–Lagrangian (CEL) approach has been developed to overcome the difficulties with regard to finite element method and large deformation analyses. This new method is investigated regarding its capabilities. First, a benchmark test, a strip footing problem is investigated and compared to analytical solutions and results of comparable finite element analyses. This benchmark test shows that CEL is well suited to deal with problems which cannot be fully solved using FEM. In further applications the CEL approach is applied to more complex geotechnical boundary value problems. First, the installation of a pile into subsoil is simulated. The pile is jacked into the ground and the results received from these analyses are compared to results of classical finite element simulations. A second case study is the simulation of a ship running aground at an embankment. The results of the CEL simulation are compared to in situ measurement data. Finally, the capabilities of the new CEL approach are evaluated regarding its robustness and efficiency. [ABSTRACT FROM AUTHOR]

Lungworms, a world wild distributed parasites cause serious respiratory diseases to the pigs. A high infection rate of Metastrongylus lungworms has been found in Tibetan pigs being slaughtered in different slaughter houses of Tibet autonomous region. The main aim of our study was to detect and confirm the lungworm parasite by the genetic characterization of mitochondrial cox1genome isolated from the lungs of Tibetan pig. The adult lungworms were collected from the lungs of slaughtered pigs and identification was done through morphological examinations. Total genomic DNA of the extracted worms was performed and a fragment (∼450 bp) of the cox1 of mitochondrial (mt) gene was amplified. Amplicons were cloned into PGEM ® -T Easy vector and the positive clones were sequenced from a commercial company. Sequence and phylogenetic analysis were performed by software of DNAMAN and MEGA respectively. The results revealed that the lungworms infecting the Tibetan pigs were Metastrongylus pudendotectus ( M. pudendotectus ). To our knowledge, this is the first report for the isolation and identification for the genetic characterization of mitochondria (mt) genome of cox 1 of M. pudendotectus derived from Tibetan pigs in Tibet, China. [ABSTRACT FROM AUTHOR]

Objectives: This study investigated the hypothesis whether S100A1 gene therapy can improve pathological key features in human failing ventricular cardiomyocytes (HFCMs). Background: Depletion of the Ca2+-sensor protein S100A1 drives deterioration of cardiac performance toward heart failure (HF) in experimental animal models. Targeted repair of this molecular defect by cardiac-specific S100A1 gene therapy rescued cardiac performance, raising the immanent question of its effects in human failing myocardium. Methods: Enzymatically isolated HFCMs from hearts with severe systolic HF were subjected to S100A1 and control adenoviral gene transfer and contractile performance, calcium handling, signaling, and energy homeostasis were analyzed by video-edge-detection, FURA2-based epifluorescent microscopy, phosphorylation site-specific antibodies, and mitochondrial assays, respectively. Results: Genetically targeted therapy employing the human S100A1 cDNA normalized decreased S100A1 protein levels in HFCMs, reversed both contractile dysfunction and negative force-frequency relationship, and improved contractile reserve under beta-adrenergic receptor (β-AR) stimulation independent of cAMP-dependent (PKA) and calmodulin-dependent (CaMKII) kinase activity. S100A1 reversed underlying Ca2+ handling abnormalities basally and under β-AR stimulation shown by improved SR Ca2+ handling, intracellular Ca2+ transients, diastolic Ca2+ overload, and diminished susceptibility to arrhythmogenic SR Ca2+ leak, respectively. Moreover, S100A1 ameliorated compromised mitochondrial function and restored the phosphocreatine/adenosine-triphosphate ratio. Conclusions: Our results demonstrate for the first time the therapeutic efficacy of genetically reconstituted S100A1 protein levels in HFCMs by reversing pathophysiological features that characterize human failing myocardium. Our findings close a gap in our understanding of S100A1''s effects in human cardiomyocytes and strengthen the rationale for future molecular-guided therapy of human HF. [Copyright &y& Elsevier]

Abstract: An efficient, eye-safe, high-repetition-rate, single-resonant intracavity optical parameter oscillator, driven by a laser-diode (LD) end-pumped acousto-optically Q-switched Nd:YVO4 laser, based on high gray-trace resistance KTiPO4 (GTR-KTP), was demonstrated. With a pump power of 13.8W and frequency repetition rate of 40kHz, the maximum power of 1.72W with pulse width of 2.09ns at signal wavelength 1572nm is obtained. The corresponding peak power and single pulse energy is calculated to be 21kW and 43μJ, respectively. And the conversion efficiency from incident pump power at 808nm to output power at signal wavelength 1572nm is about 12.5%. The output instability is measured only to be 1% within 1h. [Copyright &y& Elsevier]

Abstract: An eye-safe, high peak power optical parameter oscillator (OPO) intracavity pumped by electro-optic Q-switched Nd:YAG laser is presented. This OPO is based on a 20mm length KTiOAsO4 crystal with non-critical phase matching (θ =90°, ) cut. An aperture ∅3mm acted as limiting diaphragm to get good beam quality of pumping laser. The output energy of 25mJ at the signal wavelength 1.53μm was obtained with repetition rate of 1Hz. The highest peak power intensity was up to 88MW/cm2 with pulse width of 4ns. Without diaphragm, the maximum output energy of 90mJ was achieved with area of light spot (∅6mm) four times larger, but the peak power intensity was lower. [Copyright &y& Elsevier]

Abstract: We examined the ability of a HIV-1-based vector (VRX494) encoding a 937-bp antisense HIV-1 envelope sequence to inhibit the replication of chimeric SIV/HIV-1 viruses encoding the HIV-1 envelope. Challenge of VRX494-transduced CEMx174 cells resulted in potent inhibition of HIV-1 and several SHIV strains. To evaluate the potential efficacy of the VRX494 vector for stem cell gene therapy, rhesus CD34+ bone marrow cells were transduced with VRX494 and then cultured on thymus stroma to induce T cell differentiation. Transduction conditions for CD34+ cells were optimized to yield high transduction efficiency with minimal effective multiplicity of infection. Purified CD4+ GFP+ T cells derived from VRX494-transduced CD34+ cells strongly inhibited SHIV HXBC2P 3.2 and SHIV 89.6P replication compared to controls. Southern blot analysis of VRX494-transduced T cell clones revealed a subset of cells with multiple proviral copies per cell. Expression of GFP and the antisense inhibitor in VRX494-transduced cells was upregulated by Tat. Analysis of HIV-1 envelope sequences in VRX494-transduced cells revealed modifications consistent with those mediated by double-stranded RNA-dependent adenosine deaminase. These results indicate that the macaque/SHIV model should serve as a useful preclinical model to evaluate this lentiviral vector expressing an HIV-1 antisense inhibitor for stem cell gene therapy for AIDS. [Copyright &y& Elsevier]

Abstract: With a non-critically phase-matched KTA crystal, a high-power intracavity optical parametric oscillator (IOPO) driven by a diode-side-pumped acousto-optically Q-switched Nd:YAG laser has been realized. The maximum average output power of 13.6W at the signal wavelength of 1534nm and 3W at the idler wavelength of 3472.7nm were obtained with the repetition rate of 18kHz, giving the optical–optical conversion efficiency of about 5.7% from diode-power at 808nm to OPO signal output, which was the highest conversion efficiency for intracavity KTA OPO with diode-side-pumping configurations to our best knowledge. At the highest output power of 13.6W, the signal pulse duration of 5.46ns was obtained, corresponding to the single pulse energy of 756μJ and peak power of 138kW, respectively. [Copyright &y& Elsevier]