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Hydraulic jumps control the bypass, erosion, and depositional processes of Froude-supercritical turbidity currents, so they represent a significant process for understanding the development of submarine geomorphology. Hydraulic jumps actively occur from submarine canyons to fans, where the seafloor slope is relatively steep. Turbidites in such areas comprise large-scale bedforms called cyclic steps, and they exhibit complex internal structures, including localized erosion and the accumulation of coarse-grained fining-upward sequences. However, it is unclear which turbidity-current properties are reflected in the heterogeneous depositional characteristics and grain-size sorting of these deposits. To this end, we conducted flume experiments to reproduce deposits associated with the hydraulic jumps of surge-type flows. Turbidity-current surges were repeatedly generated in an experimental flume with a knickpoint that transitioned from a steep to a gentle slope, resulting in cyclic steps. Overall, the upstream migration of the cyclic steps produced a downstream-upward-fining succession of turbidites. However, hydraulic jumps occurred at several places over the trough to the stoss side of the step in a single flow due to the non-uniform and unsteady flow state of the surge-type turbidite succession. As a result, the reproduced succession exhibited multiple local scours and coarse-grained fill in the lower parts of the turbidites. This suggests that multiple local scours and fining-upward trends are discriminant characteristics of cyclic-step deposits formed by surge-type supercritical turbidity currents.

The Mahalanobis-Taguchi system (MTS) is a relatively new multi-dimensional pattern recognition technology that combines Mahalanobis distance (MD) with Taguchi's robust engineering for diagnosis and...

Cavity optomechanical systems operating at the quantum ground state provide a novel way for the ultrasensitive measurement of mass and displacement and provide a new toolbox for emerging quantum information technologies. The high-frequency optomechanical devices could reach the quantum ground state at a high temperature because the access to high frequency is favorable for the cavity optomechanical devices to decouple from the thermal environment. However, reaching ultra-high frequency (THz) is extremely difficult due to the structure of cavity optomechanical devices and properties of materials. In this paper, by introducing acoustic topological interface states, we designed a THz mechanical frequency semiconductor pillar microcavity optomechanical device based on a GaAs/AlAs nanophononic superlattice. In the optomechanical system, multi-optical cavity modes are obtained and the frequency separation between adjacent optical modes is equal to the frequency of the mechanical mode (optomechanical frequency matching). By detuning the laser pump to a lower (higher) energy-resolved sideband to make a spontaneously scattering photon doubly resonate with optical cavity modes at an anti-Stokes (Stokes) frequency and pump frequency, we can achieve an anti-Stokes (Stokes) scattering efficiency 2600 (1800) times larger than that of Stokes (anti-Stokes) scattering, which provides potential for laser cooling and low threshold phonon lasing in the optomechanical system.

Two-dimensional (2D) crystals are promising materials for developing future nano-enabled technologies1-6. The cleavage of weak, interlayer van der Waals bonds in layered bulk crystals enables the production of high-quality 2D, atomically thin monolayers7-10. Nonetheless, as earth-abundant compounds, metal oxides are rarely accessible as pure and fully stoichiometric monolayers owing to their ion-stabilized 'lamellar' bulk structure11-14. Here, we report the discovery of a layered planar hexagonal phase of oxides from elements across the transition metals, post-transition metals, lanthanides and metalloids, derived from strictly controlled oxidation at the metal-gas interface. The highly crystalline monolayers, without the support of ionic dopants or vacancies, can easily be mechanically exfoliated by stamping them onto substrates. Monolayer and few-layered hexagonal TiO2 are characterized as examples, showing p-type semiconducting properties with hole mobilities of up to 950 cm2 V-1 s-1 at room temperature. The strategy can be readily extended to a variety of elements, possibly expanding the exploration of metal oxides in the 2D quantum regime.

Background Seed oil of sea buckthorn (SBT) is well known to contain high amount of polyunsaturated fatty acid (PUFA), and PUFA is generally acknowledged to promote skin hydration by reducing trans‐epidermal water loss (TEWL). Aims The present study is aimed to investigate that skin hydration offered by SBT seed oil is whether through up‐regulating AQP3 or HAS2 expression. Methods MTT assay was performed to detect cytotoxicity of SBT seed oil, and then, PCR was carried out to explore whether SBT seed oil can increase AQP3 mRNA expression in normal human epidermis keratinocytes (NHEK) cells or not. Immunofluorescence (IF) and Western blot analysis were used to test the protein level expression of AQP3 and HAS2 influenced by SBT seed oil in NHEK cells or in reconstructed epidermis skin model. Results According to the result of MTT assay, all test concentration of SBT seed oil showed no cytotoxicity to cells. 10 μg/mL SBT seed oil treatment evidently increased AQP3 mRNA level compared to negative control (NC). IF and Western blot analysis results demonstrated that AQP3 and HAS2 protein levels in NHEK cells treated with 10 μg/mL SBT seed oil were much higher than that of NC. Finally, treatment with 10 μg/mL SBT seed oil substantially up‐regulated expression of AQP3 and HAS2 protein in reconstructed epidermis skin model in comparison to NC. Conclusions In summary, our study first proved that SBT seed oil can improve skin hydration through increasing AQP3 and HAS2 expressions.

Metal chalcogenides are important members of the two-dimensional (2D) materials family and have been extensively investigated for high-performance electronic device applications. However, when they are produced on a large-scale, their carrier mobilities are strongly influenced by the surface conditions. Here, we print indium sulphide (In2S3) with the thickness down to the single unit cell limit on wafer-scale out of metallic indium liquid, in which structural indium vacancies are formed in an orderly fashion. First principles investigations reveal that the unique ordered-vacancy structure results in a highly dispersive conduction band with low effective electron mass, forming multiple band-like electronic transport channels sandwiched within the crystal structure which are less influenced by the surface conditions. Back-gated field effect transistors are fabricated, and the measured mobility is up to 58 cm2 V-1 s-1 with a high degree of reproducibility, which is amongst one of the highest reported for wafer-scale-grown ultra-thin metal chalcogenides. This establishes ordered-vacancy-enabled semiconductors in the 2D geometry as suitable alternatives for new generation high-performance electronic devices.

Laparoscopic approach for gallbladder cancer (GBC) has long been contraindicated, but few recent studies have demonstrated the oncologic outcomes of this treatment. The purpose of this study was to compare the perioperative outcomes and long-term survival for laparoscopic surgery versus traditional open surgery of GBC. Between January 2014 and December 2018, 63 GBC patients who received radical resection were enrolled in this study, with 32 patients in laparoscopic group and 31 cases in laparotomy group. Perioperative data and postoperative survival were retrospectively evaluated. Laparoscopic approach was associated with less intraoperative bleeding (267.20 ± 47.07 vs. 502.60 ± 69.70, P = 0.007), fewer postoperative days of oral diet recovery (2.34 ± 0.31 vs. 3.32 ± 0.35, P = 0.041), and hospital stay (11.03 ± 0.99 vs. 14.35 ± 1.11, P = 0.028). There were no significant differences between two groups regarding other perioperative outcomes. Patients in laparoscopic group showed better 1-year overall survival than those in laparotomy group (72.91% vs. 47.82%, P = 0.086). Subgroup analysis for GBC patients in T3 stages revealed that laparoscopic approach was associated with less intraoperative bleeding (268.00 ± 57.19 vs. 541.50 ± 101.30, P = 0.009), fewer postoperative days of hospital stay (9.87 ± 1.10 vs. 14.90 ± 1.53, P = 0.017), and improved 1-year overall survival (P = 0.023). Subgroup analysis for GBCs in TNM III and TNM IV stages showed comparable intraoperative parameters and postoperative survival between two groups. Laparoscopic surgery for GBCs may offer the comparable perioperative outcomes as conventional laparotomy procedure, and tend to be associated with less intraoperative bleeding, faster oral diet recovery, shorter hospital stay, and improved 1-year overall survival.

Health state assessment is a key technology for system Prognostic and Health Management (PHM) and an important basis for remaining useful life prediction and maintenance decision-making. Rolling bearings are key components of rotating machinery equipment and also one of the most vulnerable components. It has important theoretical and practical significance to evaluate the health state of rolling bearings. In this paper, the empirical mode decomposition (EMD) method is used to extract the vibration signal characteristics of rolling bearings, the dimension of the features is reduced by Mahalanobis-Taguchi system (MTS), and a Hidden Markov Model (HMM) is combined with Mahalanobis distance (MD) to complete health state assessment of rolling bearings. The experimental bearing life cycle data set provided by the Intelligent Maintenance Center of the University of Cincinnati is selected to verify the effectiveness of the proposed method. The experimental results show that the method can detect an early failure and has good sensitivity.

Two-dimensional (2D) crystals are promising materials for developing future nano-enabled technologies

Despite the importance of turbidity currents in environmental and resource geology, their flow conditions and mechanism are not well understood. To resolve this issue, a novel method for the invers...

Despite the importance of turbidity currents in environmental and resource geology, their flow conditions and mechanism are not well understood. To resolve this issue, a new method for the inverse ...

Rolling bearings are widely used in rotary machinery systems, their condition directly determines the normal operation of machinery, and effective recognition of bearing fault can greatly reduce maintenance time and cost. This paper proposes an integrated model which combines Binary-tree and Mahalanobis-Taguchi system (BT-MTS) to detect faults of rolling bearing. The BT-MTS consists of three stages. Firstly, the time domain, frequency domain, and time- frequency domain features are extracted from the vibration signals by feature extraction technology, such as complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN). Then, the Fisher ratio method is utilized at each node of the binary tree to design the architecture of the BT-MTS modeling. Ultimately, the trained BT-MTS is used to predict the fault types. The experimental results demonstrate that the proposed method is effective in recognizing the different categories of rolling bearings faults.

Silicon photonics has demonstrated great potential in ultrasensitive biochemical sensing. However, it is challenging for such sensors to detect small ions which are also of great importance in many biochemical processes. A silicon photonic ion sensor enabled by an ionic dopant-driven plasmonic material is introduced here. The sensor consists of a microring resonator (MRR) coupled with a 2D restacked layer of near-infrared plasmonic molybdenum oxide. When the 2D plasmonic layer interacts with ions from the environment, a strong change in the refractive index results in a shift in the MRR resonance wavelength and simultaneously the alteration of plasmonic absorption leads to the modulation of MRR transmission power, hence generating dual sensing outputs which is unique to other optical ion sensors. Proof-of-concept via a pH sensing model is demonstrated, showing up to 7 orders improvement in sensitivity per unit area across the range from 1 to 13 compared to those of other optical pH sensors. This platform offers the unique potential for ultrasensitive and robust measurement of changes in ionic environment, generating new modalities for on-chip chemical sensors in the micro/nanoscale.

We demonstrate the monolithic integration of a heralded single photon AlGaAs source and a 50/50 beamsplitter. A cross correlation measurement on the beamsplitter output ports reveals the quantum nature of the generated light.