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A dual-jet collecting device is highly efficient at picking up small-sized polymetallic nodules; however, its performance is not as effective for large nodules in deep-sea mining. To address this problem, numerical simulations have been conducted to thoroughly investigate the flow characteristics and particle motions during the collection of larger nodules. The collection performance of the enhanced device is analyzed across varying front jet velocities (Vf), suction pressures (Pout), and nozzle heights (h/d). The results reveal that increasing Vf improves the drag force and particle velocity in the jet impingement and upwelling zones, facilitating nodule lifting movement and transport. However, increasing Pout reduces the drag forces in these zones while increasing the particle velocity in the upwelling zone. A large Pout is not conducive to nodule initiation but has benefits for transport. Increasing h/d reduces the drag force in the anti-gravity direction in the jet impingement zone. The improved collecting device attains a pick-up efficiency that exceeds 80% for large-sized nodules when h/d < 1.3. The pick-up efficiency with suction pressure, which remains 40%, is higher than that without suction pressure when h/d > 1.3. The research findings may shed light on the design of more efficient dual-jet collection systems.

High-k turbulence (1 < kθρs < 5) spectrograms have been directly measured in density modulation experiments of the EAST tokamak using the collective Thomson scattering diagnostic system. Density-peaking modulation is achieved in Lower Hybrid Wave (LHW) modulation experiments, revealing that the broadband turbulence is sensitive to the power modulation of LHW and the concomitant variation of density-peaking. Additionally, the contributions of 2.45/4.6 GHz LHW to density peaking differ when Neutral Beam Injection (NBI) is on/off, displaying distinct responses of broadband turbulence in low/high frequency ranges. It is found by cross-coherence analysis that the phase angle is negative in cases without NBI, while in NBI cases it can be modulated from negative to positive, indicating a significant transition of radial turbulence propagation. These findings highlight the active control of density-peaking via auxiliary heating in tokamak plasmas and suggest the potential role of high-k turbulence in density-peaking modulation.

Antiferromagnetic (AFM) materials possess unique properties, such as rapid dynamic response, resistance to external magnetic disturbances, and the absence of a stray field. AFM materials are important members in the field of spintronics, and generating the spin current in AFM materials is one of the vital topics for AFM spintronics. The spin photovoltaic effect (SPVE) is the spin counterpart of the bulk photovoltaic effect (BPVE), where the photocurrent is spin-polarized. This effect can generate spin current in a contactless and ultra-fast way. Recently, SPVE has garnered significant interest due to its potential application in AFM spintronics and rich physical content. In this perspective, the mechanism of SPVE, including the relationship between SPVE and BPVE, and symmetry constraints are reviewed. We also provide an overview of recent progress on SPVE in AFM materials. This perspective also offers a viewpoint on this exciting area of research.

We investigated the hydraulic efficiency of spark-generated bubbles under conditions of different discharge polarities and different electrode numbers. A positive polarity discharge can generate a larger spark-induced bubble than a negative polarity discharge generated using the same electrical and electrode parameters. The hydraulic efficiency of both the positive and negative polarity discharges decreases with the increasing number of electrodes. Increasing the number of electrodes leads to faster energy injection times and higher average powers. We found that the hydraulic efficiency increases when energy injection time increases but that it decreases when the average power increases. When the energy injection time is longer than 100 µs and the average power is less than 100 kW, hydraulic efficiencies of more than 15% and 10% were realized for the positive and negative polarity discharges, respectively. These results indicate that longer energy injection times will be helpful in gaining higher hydraulic efficiency for these bubbles.

Multilayered balloon catheters are attracting more attention in recent years. Multilayered balloon catheters have some unique properties such as meso-/microscale dimensions, small wall thickness, and strict requirements of dimensional accuracy. In this study, three-layered polymeric balloon catheters composed of polyamide, ethylene vinyl acetate, and polypropylene (PA/EVA/PP) are successfully fabricated using a three-layered coextrusion die and the polymer melt flowing behavior through the extrusion die are analyzed. Both the diameter and wall thicknesses have been selected as the targeted structural parameters to investigate the effects of pulling speed, air injection volume rate, and screw speed on the quality of the extrudates. The optimal combination of these three operating conditions has been achieved. It is found that pulling speed can significantly affect the diameters of the extruded balloon catheters. The variation interval values of outer profile diameter and inner cavity diameter with the extrusion experiments are 20.95% and 13.04%, respectively. The screw speed of each layer has a great influence on the wall thickness of each layer. Through the influence of outer screw speed, middle screw speed and inner screw speed, the variation interval values for outer layer wall thickness, middle layer wall thickness, and inner layer wall thickness are 31.06%, 35.69%, and 31.35%, respectively. The air injection volume rate has negligible effect.

Ion Cyclotron Range of Frequencies (ICRF) heating and Neutral Beam Injection (NBI) can have synergy due to the acceleration of NBI beam ions by ICRF wave fields at their harmonics. To understand the influence of ICRF-NBI synergy on fast ion distribution and plasma performance, dedicated experiments and TRANSP simulations have been carried out on EAST. The simulation results are consistent with the experimental results. They show that the ICRF-NBI synergy not only accelerates the NBI beam ions with energy lower than 80 keV to energy larger than 300 keV, but also generates fusion neutrons with energy larger than 3 MeV. Moreover, ICRF-NBI synergy improves the plasma performance by increasing the poloidal beta, plasma stored energy, core ion temperature, total neutron yield and kinetic pressure. In a typical H-mode plasma with 1.0 MW NBI and 1.5 MW ICRF power, it was observed that ICRF-NBI synergy increases the poloidal beta, plasma stored energy, core ion temperature and neutron yield by ∼35%, 33%, 22% and 80%, respectively. Various parameter scans show that the ICRF-NBI synergetic effects can be enhanced by decreasing the minority ion concentration or the distance between the harmonic resonance and magnetic axis, or by increasing the ICRF heating power or NBI beam energy. Consequently, this leads to a generation of fast ions with higher energy. For instance, the maximum energy of the fast ion tail increases from 300 to 600 keV as n(H) decreases from 5% to 0.1%.

A new outburst of GX 339−4 in 2021 was monitored by the Hard X-ray Modulation Telescope (Insight-HXMT). By using the data of Insight-HXMT from 2021 February to March, we make an X-ray timing analysis of this new outburst. Based on the results of the count rates, hardness–intensity diagram, and power density spectrum (PDS), we confirm that the source exhibits spectral transitions from the low-hard state (LHS) to the hard-intermediate state (HIMS). During the transition from the LHS to the HIMS, low-frequency quasi-periodic oscillations (QPOs) are detected in the PDS. We found that these QPOs are all type C QPOs with centroid frequencies evolving from 0.1 to 0.6 Hz in the LHS and in the 1–3 Hz frequency range in HIMS. The QPO features above 50 keV are reported for the first time in this black hole by Insight-HXMT. The QPO rms stays stable with time but decreases with energy at a higher energy above ∼10 keV. We also find that the phase lag of the type C QPO is close to zero in the early outburst stage but becomes positive as the outburst evolves, with a hard lag of ∼0.6–1.2 rad in 50–100 keV. The implications of the phase lag in high energy bands and the possible physical mechanisms to explain those observations are also discussed.

In this study, we report lipid biomarker patterns and phylogenetic identities of key microbial communities mediating anaerobic oxidation of methane (AOM) in active mud volcanoes (MVs) on the continental slope of the Canadian Beaufort Sea. The carbon isotopic compositions (δ13C) of sn-2- and sn-3-hydroxyarchaeol showed the highly 13C-depleted values (−114 ‰ to −82 ‰) associated with a steep depletion in sulfate concentrations within 0.7 m of sediment depths. This suggested the presence of methanotrophic archaea involved in sulfate-dependent AOM, albeit in a small amount. The ratio of sn-2-hydroxyarchaeol to archaeol (> 1) and operational taxonomic units (OTUs) indicated that the anaerobic methanotrophic archaea (ANME) clades ANME-2c and ANME-3 were involved in AOM. Higher δ13C values of archaeol and biphytanes (BPs; -55.2±10.0 ‰ and -39.3±13.0 ‰, respectively) suggested that archaeal communities were also assimilating AOM-derived inorganic carbon. Furthermore, the distinct distribution patterns of methanotrophs in the three MVs appears to be associated with varying intensities of ascending gas fluids. Consequently, our results suggest that the niche diversification of active mud volcanoes has shaped distinct archaeal communities that play important roles in AOM in the Beaufort Sea.

Abstract Background In Canada, government insurance covers eye care services provided by ophthalmologists and other physicians. However, government coverage for services provided by optometrists, non-medical school trained primary eye care providers, varies regionally. Little is known about the impact of a funding model in which ophthalmologist services are government-insured but services provided by optometrists are not, on eye care utilization and eye disease detection and treatment. We aimed to address this question by examining geographic variations in eye care service utilization on Prince Edward Island (PEI). Methods PEI physician-billing data from 2010 to 2012 was analyzed across five distinct geographic regions (Charlottetown, Summerside, Prince, Queens & Kings and Stratford). The residential location of patients and practice locations of eye care providers were identified using the first three digits of their respective postal code. Age-standardized rates were computed for comparisons across different regions. Results There were six ophthalmologists practicing on PEI, five with offices in Charlottetown. Twenty optometrists practiced on the island with offices across the province. Stratford is closest and Prince farthest from Charlottetown. Age-standardized utilization rates of ophthalmologists per 100 populations were 10.44 in Charlottetown and 10.90 in Stratford, which was significantly higher than in other regions (7.74–8.92; p

Objective This experiment was to evaluate the effects of the dietary energy levels on the physiological parameters and reproductive performance during gestation over three parities in sows. Methods A total of 52 F1 gilts (Yorkshire×Landrace) were allotted to one of four dietary treatments using a completely randomized design. The treatments contained 3,100, 3,200, 3,300, or 3,400 kcal of metabolizable energy (ME)/kg diet but feed was provided at 2.0, 2.2, and 2.4 kg/d in the first, second and third parity, respectively. Results The body weight and body weight gain during gestation increased as the dietary energy level increased (p

Abstract Background In 2006, the European Union (EU) has decided to forbid use of antibiotics as growth promoters. Although many researches had been conducted about fiber source as alternatives of antibiotics, there are still lack of reports in the literature about the optimum level of sugar beet pulp supplementation, affecting growth performance and nutrient digestibility in weaning pigs. Therefore, different level of sugar beet pulp was added to diets to determine the effects of sugar beet pulp supplementation on growth performance, nutrient digestibility, fecal microflora, blood profile and incidence of diarrhea in weaning pigs. Methods A total of 200 weaning pigs [(Yorkshire × Landrace) × Duroc], averaging 9.01 ± 1.389 kg of initial body weight were, allotted to 5 treatments in a randomized complete block (RCB) design. Each treatment was composed of 4 replicates with 10 pigs per pen. The treatments were control treatment: Corn-SBM basal diet + ZnO (phase 1: 0.05%; phase 2; 0.03%) and four different levels of sugar beet pulp were supplemented in Corn-SBM basal diet (3, 6, 9 or 12%). Two phase feeding programs (phase 1: 1–2 weeks; phase 2: 3–5 weeks) were used for 5 week of growth trial. Results In feeding trial, there were no significant differences in growth performance and incidence of diarrhea among treatments. The E.coli counts were not significantly different among dietary treatments but linear response was observed in Lactobacillus counts as sugar beet pulp supplementation increased (P

By combining first-principles calculations and symmetry arguments, we propose that the half-metallic phase of K _2 Cr _8 O _16 presents ferromagnetic Weyl fermions. In particular, K _2 Cr _8 O _16 possesses two pairs of Weyl nodes, which originate from two groups of nodal lines connected by the mirror reflection symmetry. We show that the non-trivial topological properties of K _2 Cr _8 O _16 come from the partially occupied t _2g states of Cr, and we also demonstrate that such exotic topological feature is robust. The topological surface states and corresponding Fermi arcs are revealed. As K _2 Cr _8 O _16 is a realistic and widely studied material, our results suggest that K _2 Cr _8 O _16 is an ideal candidate for studying ferromagnetic Weyl fermions. In addition, K _2 Cr _8 O _16 possesses several interesting phenomena, such as the co-existence of charge density wave and Weyl fermions, even pairs of FM Weyl points, and tunable distribution of Weyl points, which will attract intensive attentions in this field.

This study was conducted to examine the effects of supplementing brown seaweed by-products (BSB) in the diet of ruminants on ruminal fermentation characteristics, growth performance, endocrine response, and milk production in Holstein cows. In Experiment 1, the effects of different levels (0%, 2%, and 4% of basal diet as Control, 2% BSB, 4% BSB, respectively) of BSB were evaluated at 3, 6, 9, 12, and 24 h in vitro batch culture rumen fermentation. The pH tended to be higher for the higher level of BSB supplementation, with the pH at 12 h being significantly higher (p

The effects of the waveguide layer on the band structure of Rayleigh waves are studied in this work based on a one-dimensional acoustic superlattice lithium niobate substrate coated with a waveguide layer. The present phononic structure is formed by the periodic domain-inverted single crystal that is the Z-cut lithium niobate substrate with a waveguide layer on the upper surface. The plane wave expansion method (PWE) is adopted to determine the band gap behavior of the phononic structure and validated by the finite element method (FEM). The FEM is also used to investigate the transmission of Rayleigh waves in the phononic structure with the interdigital transducers by means of the commercial package COMSOL. The results show that, although there is a homogeneous waveguide layer on the surface, the band gap of Rayleigh waves still exist. It is also found that increasing the thickness of the waveguide layer, the band width narrows and the band structure shifts to lower frequency. The present approach can be taken as an efficient tool in designing of phononic structures with waveguide layer.

Three Korean native steers (779±24 kg) fitted with duodenal cannulas were used in a 3×3 Latin square design to investigate the influence of oral administration of soluble proteins, intact casein (IC) and acid hydrolyzed casein (AHC), on gastrointestinal hormone (GIH) secretion in the blood and pancreatic α-amylase activity in the duodenum. Oral treatment consisted of a basic diet (control), IC (C+100% protein), or AHC (C+80% amino acid, 20% peptide) for 21 d. Blood and duodenum samples were collected for measurement of serum GI hormones, and pancreatic α-amylase activity was determined at 900, 1030, 1330, 1630, and 1930 h after feeding on d 21 of treatment. The levels of serum cholecystokinin (CCK) and secretin in the IC treatment group were higher compared to the other treatment groups (p

Global climate variability affects important local hydro-meteorological variables like precipitation and temperature. The Southern Oscillation (SO) is an easily quantifiable major driving force that gives impact on regional and local climate. The relationships between SO and local climate variation are, however, characterized by strongly nonlinear processes. Due to this, teleconnections between global-scale hydro-meteorological variables and local climate are not well understood. In this paper, we suggest to study these processes in terms of nonlinear dynamics. Consequently, the nonlinear dynamic relationship between the Southern Oscillation Index (SOI), precipitation, and temperature in Fukuoka, Japan, is investigated using a nonlinear multivariable approach. This approach is based on the joint variation of these variables in the phase space. The joint phase-space variation of SOI, precipitation, and temperature is studied with the primary objective to obtain a better understanding of the dynamical evolution of local hydro-meteorological variables affected by global atmospheric-oceanic phenomena. The results from the analyses display rather clear low-order phase space trajectories when treating the time series individually. However, when plotting phase space trajectories for several time series jointly, complicated higher-order nonlinear relationships emerge between the variables. Consequently, simple data-driven prediction techniques utilizing phase-space characteristics of individual time series may prove successful. On the other hand, since either the time series are too short and/or the phase-space properties are too complex when analysing several variables jointly, it may be difficult to use multivariable statistical prediction techniques for the present investigated variables. In any case, it is essential to further pursue studies regarding links between the SOI and observed local climatic and other geophysical variables even if these links are not fully understood in physical terms.

Visceral afferents send information via cranial nerves to the nucleus tractus solitarius (NTS). The NTS is the initial step of information processing that culminates in homeostatic reflex responses. Recent evidence suggests that strong afferent synaptic responses in the NTS are most often modulated by depression and this forms a basic principle of central integration of these autonomic pathways. The visceral afferent synapse is uncommonly powerful at the NTS with large unitary response amplitudes and depression rather than facilitation at moderate to high frequencies of activation. Substantial signal depression occurs through multiple mechanisms at this very first brainstem synapse onto second order NTS neurons. This review highlights new approaches to the study of these basic processes featuring patch clamp recordings in NTS brain slices and optical techniques with fluorescent tracers. The vanilloid receptor agonist, capsaicin, distinguishes two classes of second order neurons (capsaicin sensitive or capsaicin resistant) that appear to reflect unmyelinated and myelinated afferent pathways. The differences in cellular properties of these two classes of NTS neurons indicate clear functional differentiation at both the pre- and postsynaptic portions of these first synapses. By virtue of their position at the earliest stage of these pathways, such mechanistic differences probably impart important differentiation in the performance over the entire reflex pathways.

The effect of rare earth element Nd addition on the microstructure and martensitic transformation behavior of Ni50Ti50−xNdx (x=0, 1, 3, 7, 20) shape memory alloy was investigated experimentally. The results showed that the microstructure of Ni-Ti-Nd ternary alloy consists of the NiNd phase and the NiTi matrix. One-step martensitic transformation was observed in all alloys. The martensitic transformation start temperature Ms increased gradually with increasing Nd content for Ni-Ti-Nd alloys.

Image jitters occur in the video of the autonomous robot moving on bricks road, which will reduce robot operation precision based on vision. In order to compensate the image jitters, the affine transformation kinematics were established for obtaining the six image motion parameters. The feature point pair detecting method was designed based on Eigen-value of the feature windows gradient matrix, and the motion parameters equation was solved using the least square method and the matching point pairs got based on the optical flow. The condition number of coefficient matrix was proposed to quantificationally analyse the effect of matching errors on parameters solving errors. Kalman filter was adopted to smooth image motion parameters. Computing cases show that more point pairs are beneficial for getting more precise motion parameters. The integrated jitters compensation software was developed with feature points detecting in subwindow. And practical experiments were conducted on two mobile robots. Results show that the compensation costing time is less than frame sample time and Kalman filter is valid for robot vision jitters compensation.

We report on the tunable photovoltaic effect of self-doped single-crystal SrTiO3 (STO), a prototypical perovskite-structured complex oxide, and evaluate its performance in Schottky junction solar cells. The photovaltaic characteristics of vacuum-reduced STO single crystals are dictated by a thin surface layer with electrons donated by oxygen vacancies. Under UV illumination, a photovoltage of 1.1 V is observed in the as-received STO single crystal, while the sample reduced at 750 °C presents the highest incident photon to carrier conversion efficiency. Furthermore, in the STO/Pt Schottky junction, a power conversion efficiency of 0.88% was achieved under standard AM 1.5 illumination at room temperature. This work establishes STO as a high-mobility photovoltaic semiconductor with potential of integration in self-powered oxide electronics.

OBJECTIVE: Breast cancer (BC) is one of the most ordinary fatal cancers. Recent studies have identified the vital role of genes in the development and progression of Tri-negative breast cancer (TNBC). In this research, DGCR8 was studied to identify how it functioned in the metastasis of TNBC. PATIENTS AND METHODS: DGCR8 expression of tissues was detected by quantitative Real Time-Polymerase Chain Reaction (qRTPCR) in 50 TNBC patients. Wound healing assay and transwell assay were used to observe the changes in the biological behaviors of TNBC cells through knockdown or overexpression of DGCR8. In addition, qRT-PCR and Western blot assay were performed to discover the potential target protein of DGCR8 in TNBC. RESULTS: DGCR8 expression level in TNBC samples was higher than that of adjacent ones. Besides, the migration ability and invasion ability of TNBC cells were inhibited after DGCR8 was silenced, while they were promoted after DGCR8 was overexpressed. In addition, TGF-β was downregulated after silencing of DGCR8 in TNBC cells, while TGF-β was upregulated after overexpression of DGCR8 in TNBC cells. Furthermore, TGF-β was upregulated in TNBC tissues, which was positively associated with DGCR8. CONCLUSIONS: Our study uncovers a new oncogene in TNBC and suggests that DGCR8 can enhance TNBC cell migration and invasion via targeting TGF-β, which provides a novel therapeutic target for TNBC patients. [ABSTRACT FROM AUTHOR]