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A meshfree orthotropic laminated shell model for geometrically nonlinear static and dynamic analysis based on the reproducing kernel particle method (RKPM) and the Mindlin-Reissner shell theory is proposed for the first time, suitable for dealing with the finite deformation of composite shell structures of arbitrary geometry in engineering. The Mindlin-Reissner shell theory is adopted to describe the geometric configuration of the laminated shells via a single-layer particle. Then, the Galerkin weak form governing equations are established explicitly and discretized using RKPM and linear transformation in the thickness direction. Furthermore, a laminate stacking sequence that can eliminate the coupling terms of linear and angular acceleration is proposed for simplification. For considering the orthotropic materials, the stress–strain transformation between local and material coordinates is introduced. A stiffened laminated shell model is also presented for simulating complex composited structures. The accuracy and convergence of the proposed laminated shell model are verified through several static and dynamic benchmarks, demonstrating the ability of the presented model to solve the nonlinear response of composite structures. [ABSTRACT FROM AUTHOR]

Efficient delafossite CuCoO 2 photo(electro)catalysts necessitate effective separation and transport of photogenerated carriers to enable the production of solar fuel. Addressing this requirement, the current study employed facet engineering to induce the surface polarization effect. Hydrothermal conditions were utilized to prepare CuCoO 2 photo(electro)catalysts with diverse morphologies and sizes. Specifically, CuCoO 2 hexagonal nanosheets, predominantly exposing the (001) facet and possessing a thickness of 120 nm, exhibited optimal performance, as evidenced by a photocurrent density of 40 μA/cm2 under zero-bias conditions and 90 % degradation of tetracycline hydrochloride within 150 min. To overcome the limitations associated with hydrothermal preparation, Ca substitutional doping was employed. This doping strategy caused disruption of the O–Cu–O dumbbell-like structural motif, transforming CuCoO 2 into an open-layered structure while simultaneously reducing the thickness of CuCoO 2 hexagonal nanosheets to 30 nm. Consequently, an enhancement in the photo(electro)catalytic performance was achieved. By striking a balance between the surface polarization effect and the doping effect, CuCoO 2 hexagonal nanosheets with 0.5 % Ca doping content and a thickness of 80 nm exhibited the most significant photo(electro)catalytic performance. This study presents a feasible strategy and concept for optimizing the morphology and hydrothermal preparation conditions of CuCoO 2 nanomaterials, leading to improved photo(electro)catalytic performance. [Display omitted] • Surface polarization enhances carrier separation and transport in CuCoO 2 photoelectrodes. • CuCoO 2 hexagonal nanosheets exhibit superior photo(electro)catalytic activity. • Ca doping overcomes limitations in hydrothermal synthesis for preparation thinner CuCoO 2 nanosheets. [ABSTRACT FROM AUTHOR]

The MAB phases gain large attention in today's world because of their combination of metallic and ceramic. In our previous work, the periodic layered structures (PLSs) containing Cr-Al-B MAB phase were formed at the Fe-Cr-B cast steel/molten Al interface. This work reports the preparation method of the new A-site alloyed Cr-Al-B MAB phase through hot-dip aluminizing (HDA) in different Al melts and subsequent thermal diffusion treatment (TDT) of Fe-Cr-B cast steel. It was found that the Zn and Si in the Al melts had great effects on the formation and microstructure evolution of the Cr-Al-B MAB phase formed during HDA and TDT. Both Zn and Si could partially replace the Al atoms in Cr-Al-B MAB phase, leading to forming a solid solution with double A atoms. The Cr-(Al, Zn)-B and Cr-(Al, Si)-B MAB phases were achieved by A-site replacement in Cr-Al-B MAB phase. Meanwhile, Zn thickened the thickness of this MAB phase, while, Si decreased that of the MAB phase. However, when they were dopped simultaneously, Zn atom preferentially replaced Al atom in Cr-Al-B MAB phase with that of the substitution of Si not happening. [ABSTRACT FROM AUTHOR]

Bubble pulsation is a characteristic multiphase compressible flow, which involves periodic oscillation and strong pressure wave and is vulnerable to boundary conditions. The smoothed particle hydrodynamics (SPH) has limitations in imposing the fluid boundary suitable for such problems, which have been verified first with the state-of-the-art SPH boundaries. It brings challenges to the three-dimensional modeling. Then, we propose to combine SPH with the finite volume method via the spatial coupling to deal with this problem. The accuracy of the coupled method has been validated by comparisons with other numerical methods and the theoretical equation from the spherical pulsation to the more complex bubble oscillations. Good agreements are obtained in terms of the bubble radius and the pulse pressure peak. The conclusions drawn in this work and the computational framework lay the foundation for the further complicated study on the bubble dynamics, the complete process of underwater explosion, and the related fluid–structure interaction problems. [ABSTRACT FROM AUTHOR]

In this work, we established a novel theory for the dynamics of oscillating bubbles such as cavitation bubbles, underwater explosion bubbles, and air bubbles. For the first time, we proposed bubble dynamics equations that can simultaneously take into consideration the effects of boundaries, bubble interaction, ambient flow field, gravity, bubble migration, fluid compressibility, viscosity, and surface tension while maintaining a unified and elegant mathematical form. The present theory unifies different classical bubble equations such as the Rayleigh–Plesset equation, the Gilmore equation, and the Keller–Miksis equation. Furthermore, we validated the theory with experimental data of bubbles with a variety in scales, sources, boundaries, and ambient conditions and showed the advantages of our theory over the classical theoretical models, followed by a discussion on the applicability of the present theory based on a comparison to simulation results with different numerical methods. Finally, as a demonstration of the potential of our theory, we modeled the complex multi-cycle bubble interaction with wide ranges of energy and phase differences and gained new physical insight into inter-bubble energy transfer and coupling of bubble-induced pressure waves. [ABSTRACT FROM AUTHOR]

High-pressure bubble dynamics often involves many complex issues, including large deformations and inhomogeneities, strong compression, moving interfaces, and large discontinuities, that bring challenges to numerical simulations. In this work, an axisymmetric Riemann–smoothed particle hydrodynamics (SPH) method is used to simulate high-pressure bubbles near different boundaries. This Riemann–SPH can adopt the real sound speed instead of the artificial one for the air phase in the bubble. Therefore, the real compressibility of the air phase can be considered, and the corresponding time step is significantly increased. To avoid unphysical interface penetration and maintain relatively homogeneous particle distribution, a new and simple particle shifting scheme for multiphase flows is proposed. Additionally, to minimize the influence of the unphysical boundary on the bubble, a large fluid domain with an optimized initial particle distribution is adopted to reduce the particle number. Several high-pressure bubbles under different boundary conditions are considered, including in a free field, near a free surface, near a solid boundary, and near a rigid sphere. Numerical results show that these bubble dynamic behaviors can be reproduced with satisfactory accuracy. [ABSTRACT FROM AUTHOR]

The exploration of novel photocatalyst is one of the important directions of developing efficient photocatalysis technology. Delafossite CuCoO2 has unique crystal structure, suitable band gap and energy band edge, and excellent catalytic activity, which is a new photocatalyst well worth developing. However, the as-prepared CuCoO2 samples in literature often have the problems of containing impurity or secondary phases, non-stoichiometry, leading to some controversies about its fundamental physicochemical properties. Moreover, there is also insufficient understanding of the use of CuCoO2 as a novel photocatalyst. Herein, one-pot hydrothermal method was used to prepare stoichiometric delafossite CuCoO2 microcrystals (~ 3.65 μm) with high purity and single-phase. Then, its detailed fundamental physicochemical properties as photocatalyst are further provided by a series of experimental characterization and density functional theory calculations. The results show that delafossite CuCoO2 exhibit outstanding semi-metallic ferromagnetism, multiple electron transitions caused by various band gap types, multi band absorption and full spectrum absorption, and has appropriate band edge position, which can be applied to HER and OER of water splitting. The photocatalytic performance of CuCoO2 was systematically tested for the first time by photocatalytic degradation of tetracycline hydrochloride, photocatalytic water-splitting, and photocurrent measurement in PEC cell. Under visible light irradiation, the as-prepared CuCoO2 can degrade more than 90% of tetracycline hydrochloride within 4 h. Without sacrificial agent and cocatalyst, the shows the hydrogen and oxygen evolution rates from photocatalytic water-splitting of as-prepared CuCoO2 reached to 2.60 and 128.53 μmol/h g, respectively. In the three-electrode electrochemical cell with 1 M Na2SO4 electrolyte and zero-bias, the photocurrent density of CuCoO2 based photocathode reached to 20 μA/cm2. These findings prove that CuCoO2 has obvious advantages and great potential as a visible-light-driven photocatalyst. [ABSTRACT FROM AUTHOR]

Low-cost beam coverage is one of the main goals of indoor wireless communication. We propose a low-cost beam steering (BS) antenna by using a hemispherical active frequency selective surface (AFSS) and its embedded varactors. At the same time, in the 3-D spherical coordinate system, we propose a universal design method for this type of antenna based on the principle of phase compensation. The designed BS antenna can realize energy gathering and beam switching in the quasi-full airspace on the ground. BS without phase shifter and reasonable allocation of energy brings the advantages of low cost. The proposed approach provides a feasible scheme for improving the robustness and energy saving of wireless communication. [ABSTRACT FROM AUTHOR]

In this paper, an active frequency-selective rasorber (AFSR) with a wide tunable range of passband windows is proposed. The proposed AFSR includes an absorption layer, a frequency selective layer, and an air spacer between them. The absorption layer is embedded with resistors to aid in the absorption of out-of-band unprofitable signals, and the frequency selective layer is designed to provide tunable transmission passbands through in-band beneficial signals. A design method for the AFSR embedded with varactors based on equivalent circuit model is proposed. Driven by an applied voltage, the transmission passband of the proposed AFSR can be shifted from 3.4 to 6.9 GHz. The absorption bandwidth covers from 6.4 to 14.1 GHz. In addition, the proposed AFSR exhibits stable performances up to 45° angle of incidence wave. The measurement results of the fabricated prototype are in good agreement with the simulation results. This work provides a feasible solution for flexible simultaneous regulation of radiation and scattering. [ABSTRACT FROM AUTHOR]

Background: Major depressive disorder is characterized by not only monoamine neurotransmitters deficiencies but also persistent neuroinflammation. The complement system is an attractive therapeutic target for various inflammation-related diseases due to its early activation in inflammatory processes. Results: In the present study, the dynamic alteration of complement C3 and its receptor C3aR during the occurrence of depression and the mechanism of astrocyte-microglia IL-1R/C3/C3aR on synaptic pruning were investigated. The proteomic analysis firstly showed that chronic stress caused an elevation of C3. GO analysis indicated that complement system-mediated synaptic pruning signaling was involved in depression. The dynamic observation indicated that C3/C3aR was activated in the early onset and throughout the course of depression induced by lipopolysaccharide (LPS) and chronic stress. In contrast, C3aR blockade inhibited the hyperactivation of microglial APT2/DHHC7 palmitoylation cycle, which mediated the translocation of STAT3 and the expression of proinflammatory cytokines. Meanwhile, C3aR blockade also attenuated the synaptic pruning and enhanced the synaptogenesis in the prefrontal cortex of mice. Moreover, the blockade of IL-1R/NF-κB signaling pathway reduced the release of C3 from astrocyte. Conclusions: The current study demonstrates that astrocyte-microglia IL-1R/C3/C3aR activation causes the abnormal synaptic pruning in depression, and suggests that the activation of complement C3/C3aR may be particularly helpful in predicting the onset stage of depression. [ABSTRACT FROM AUTHOR]

Background: Hepatocellular carcinoma (HCC) accounts for the majority of liver cancer cases, while metastasis is considered the leading cause of HCC-related death. However, the currently available treatment strategies for efficient suppression of metastasis are limited. Therefore, novel therapeutic targets to inhibit metastasis and effectively treat HCC are urgently required. Methods: Wound healing and Transwell assays were used to determine the migration and invasion abilities of HCC cells in vitro. Quantitative real-time PCR (qRT-PCR), protein array, immunofluorescence, and immunoprecipitation experiments were used to study the mechanism of DYRK1A-mediated metastasis. A tail vein metastasis model and H&E staining were utilized to assess metastatic potential in vivo. Results: The results of the current study demonstrated that dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A) was upregulated in HCC tissues compared with normal liver tissues. Additionally, the level of DYRK1A was increased in primary HCC tissues of patients with metastasis compared with those of patients without metastasis, and DYRK1A overexpression correlated with worse outcomes in liver cancer patients. Gain- and loss-of-function studies suggested that DYRK1A enhanced the invasion and migration abilities of HCC cells by promoting epithelial-mesenchymal transition (EMT). Regarding the promoting effect of DYRK1A on cell invasion, the results showed that DYRK1A was coexpressed with TGF-β/SMAD and STAT3 signalling components in clinical tumour samples obtained from patients with HCC. DYRK1A also activated TGF-β/SMAD signalling by interacting with tuberous sclerosis 1 (TSC1) and enhanced metastasis of HCC cells by activating STAT3. Furthermore, DYRK1A promoted EMT by cooperatively activating STAT3/SMAD signalling. Conclusion: Overall, the present study not only uncovered the promoting effect of DYRK1A on HCC metastasis and revealed the mechanism but also provided a new approach to predict and treat metastatic HCC. [ABSTRACT FROM AUTHOR]

To predict the ignition time and mass loss rate of rigid polyurethane foam (RPU) under various radiative conditions, numerical models with a multi-step thermal degradation process have been developed based on thermogravimetric and combustion experiments. Kinetic parameters are computed via Particle Swarm Optimization with a five-step mechanism. Combustion properties of RPU under various external radiative conditions have been analyzed. From both surface absorption and in-depth absorption, one-dimensional ignition models have been established and solved via COMSOL Multiphysics. According to the ignition criterion, ignition temperature, the numerical ignition model has been established and validated by experimental results. The critical mass flux and its relationship with the external heat flux have been discussed. Moreover, the mass loss rate has been predicted by numerical models. The proposed models in this work potentially have the guiding significance for charring property polymer combustion. [ABSTRACT FROM AUTHOR]

This study presents an experimental investigation of the dynamic properties of underwater explosion (UNDEX) bubble pairs produced with a range of phase differences Δθ, defined as 2π(t1−t2)/Tosc, where ti (i = 1,2) represents the bubble inception moment and Tosc is the experimentally obtained first period of a single UNDEX bubble. Each bubble was generated by a spherical hexogen explosive charge detonated in a cubical tank and observed via high-speed photography. The phase difference was adjusted by setting different delays between the two detonations, with an accuracy of 1.0 ms. Experiments were conducted with both horizontally and vertically positioned bubble pairs and with single bubbles as well. UNDEX bubble pairs are subject to a larger buoyancy effect than cavitation or spark-generated bubble pairs. The resultant bubble behavior in the bubble–bubble interaction is more complex and is yet to be understood. In our experiments, various bubble parameters, including bubble pulsation periods, bubble elongation ratios, and collapse-induced shock wave pressures bubble, were measured and studied. Dependence of the bubble dynamics on Δθ was found, demonstrating the significant influence of Δθ on the morphology and shock wave pressure of bubble pairs. The findings suggest a method of strengthening or weakening the damage potential of an UNDEX bubble pair based on the proper adjustment of the delay between two detonations. It may also lead to a better understanding of the dynamics of interacting bubbles with buoyancy effects. [ABSTRACT FROM AUTHOR]

For a scalar integrable model, it is generally believed that the solitons interact with each other elastically, for instance, multi-bright solitons from the nonlinear Schrödinger equation and the Korteweg-de Vries equation, etc. We obtain double-valley dark solitons from the defocusing Hirota equation by the Darboux transformation. Particularly, we report a remarkable phenomenon for the inelastic interaction of the double-valley dark solitons, in contrast to the solitons interacting with each other elastically for a scalar integrable model in previous works. Furthermore, we give the explicit conditions for the elastic collision based on the asymptotic analysis results. It is shown that the double-valley dark solitons could also admit elastic interaction under the special parameters settings. [ABSTRACT FROM AUTHOR]

Interaction between a two-phase fluid and a structure involving contact line dynamics is a common phenomenon. In this paper, we aim to develop a fluid–solid coupling model that can study contact line dynamics in the case of a high density ratio between the two fluids. The fluids are treated using a multiphase lattice Boltzmann flux solver (MLBFS) that uses the cell-centered finite volume method to obtain macroscopic flow variables, and the interface fluxes are reconstructed locally by the standard lattice Boltzmann method (LBM) solutions. This approach retains the advantages of the original LBM while being more flexible in handling nonuniform grids and external force terms. The immersed boundary method (IBM) is an effective method for processing structural information, and here, the implicit boundary-condition-enforced IBM is used to accurately satisfy the Dirichlet boundary condition (no-slip boundary). Moreover, the Neumann boundary condition is deemed to represent the contribution from the structure boundary flux and is incorporated into the IB-MLBFS. The developed IB-MLBFS is verified by several test cases, including contact line motion of a two-phase fluid along a circular cylinder and droplet spreading on a flat plate, where both equilibrium results and dynamic process are correctly reproduced for different density ratios and wettability conditions. Furthermore, based on the IB-MLBFS established here, the contact line dynamics of a two-phase fluid between two square cylinders or two circular cylinders is studied. The effects of distance, structure size, and wettability on the interface state and the contact angle are studied in detail. The robustness of the proposed model is verified. [ABSTRACT FROM AUTHOR]

Interactions between plants and insects are among the most important life functions for all organism at a particular natural community. Usually a large number of samples are required to identify insect diets in food web studies. Previously, Sanger sequencing and next generation sequencing (NGS) with short DNA barcodes were used, resulting in low species‐level identification; meanwhile the costs of Sanger sequencing are expensive for metabarcoding together with more samples. Here, we present a fast and effective sequencing strategy to identify larvae of Lepidoptera and their diets at the same time without increasing the cost on Illumina platform in a single HiSeq run, with long‐multiplex‐metabarcoding (COI for insects, rbcL, matK, ITS and trnL for plants) obtained by Trinity assembly (SHMMT). Meanwhile, Sanger sequencing (for single individuals) and NGS (for polyphagous) were used to verify the reliability of the SHMMT approach. Furthermore, we show that SHMMT approach is fast and reliable, with most high‐quality sequences of five DNA barcodes of 63 larvae individuals (54 species) recovered (full length of 100% of the COI gene and 98.3% of plant DNA barcodes) using Trinity assembly (up‐sized to 1015 bp). For larvae diets identification, 95% are reliable; the other 5% failed because their guts were empty. The diets identified by SHMMT approach are 100% consistent with the host plants that the larvae were feeding on during our collection. Our study demonstrates that SHMMT approach is reliable and cost‐effective for insect‐plants network studies. This will facilitate insect‐host plant studies that generally contain a huge number of samples. [ABSTRACT FROM AUTHOR]

The physics of cavitation bubbles in water has been extensively studied for over a century. However, our understanding of bubble dynamics in binary immiscible fluids, such as a water-oil system, is limited. These systems have recently gained a lot of interest due to their relevance in modern medical treatment, emulsification, and the food industry. In this study, we establish an accurate and inexpensive three-dimensional boundary integral (BI) model for inertial cavitation bubble dynamics in binary immiscible fluid systems. Our novel scheme for solving velocities on the flow boundaries, expressed in a matrix form, can be easily extended to complex situations where multiple bubbles are generated in different phases. Additionally, we employ a density potential method and a weighted moving least-squares method to maintain a high level of mesh regularity. Our results demonstrate that the proposed 3D model is comparable in accuracy to a 3D axisymmetric model by comparing it against analytical solutions and the results obtained from an axisymmetric model. Furthermore, we compare our numerical simulations against a purposely conducted experiment for the bubble-droplet interaction, and excellent agreement is achieved. For the first time, we present simulation results of two-bubble interactions with an initially flat fluid-fluid interface and inside a droplet surrounded by a second fluid. We also reveal the dependences of the two-bubble morphologies, flow patterns, and jet velocities on the density ratio between the two phases. Finally, we find a significant difference in the mechanism of fluid mixing by multiple bubbles compared to that of a single bubble case. • We established a 3D model for inertial bubbles in binary immiscible fluids. • Our 3D model has shown comparable accuracy to an axisymmetric model. • We reproduce the essential physics in an experiment of bubble-droplet interaction. • We unveil novel fluid-mixing mechanisms with multiple bubbles. • We explore the dependencies of two-bubble interactions on the density ratio. [ABSTRACT FROM AUTHOR]

We herein report a case in which the trachea could be completely sealed only when the cuff pressure reached 100 cmH2O. An excessive cross‐sectional area of the trachea is a rare phenomenon, but we believe that our case will be helpful for clinicians who encounter similar situations. [ABSTRACT FROM AUTHOR]

Moso bamboo (Phyllostachysheterocycla (Carr.) Mitford cv. Pubescens) is an economically valuable plant in bamboo production areas of southern China, for which the management mode is crucial for improving the comprehensive benefits of bamboo forest stands. In this respect, mixed forested areas of bamboo and broad-leaved tree species can provide sound ecological management of bamboo in forestry operations. To further this goal, an outstanding question is to better understand the spatial distribution of soil bacterial communities in relation to the proportion of mixed in bamboo and broad-leaved forest. We analyzed soil bacterial community diversity and composition along a proportional gradient of 0–40% mixed-ratio (as represented by the width and size of the broad-leaved tree crown over the plot area) of bamboo and broad-leaved forest in Tianbao Yan Nature Reserve using the highthroughputsequencing of the 16S rRNA gene.Specifically, the sampling plots for the mixed proportions were divided according to the percentage of summed projected area of live broadleaf tree crowns. The main broad-leaved species in the five mixed ratio plots are the same. Each plot was 20 m × 20 m in size, and a total of 15 plots were established, three per forest ratio class. From each plot, soil samples were taken at the surface (0–10 cm depth) in December 2017. Our analysis revealed that soil bacterial diversity community structure and dominant flora changed under different mixing ratios of bamboo and broad-leaved trees. In the stand with a mixed ratio of 10–20%, the bacterial diversity index is higher; however, the diversity was lowest in the 20–30% stands. Among the 20–30% forest soil, Acidobacteria (Solibacteria, Solibacteriales, Acidobacteriales) was more abundant than in soils from other mixed-ratio stands.Redundancy analysis showed that mixed forest stand structure, soil pH, organic carbon, total nitrogen, and soil moisture all contributed to shaping the bacterial community structure. Changes in microbial communities were associated with species diversity in tree layers, availability of soil nutrients (SOC and TN), and changes in soil physical properties (MS, pH). Together, these empirical results suggest that different mixing ratios in the bamboo–broad-leaved mixed forest could influence the soil bacterial community structure indirectly, specifically by affecting the soil physical and chemical properties of the forest. [ABSTRACT FROM AUTHOR]

This paper presents numerical investigations of the nonlinear interactions between two underwater explosion (UNDEX) bubbles using the compressible Eulerian finite-element method (EFEM). The volume of fluid method is applied to capture the multi-fluid interface. In this model, the high-temperature and high-pressure gaseous products inside the UNDEX bubble are described by the equation of state for Jones–Wilkins–Lee, which allows us to consecutively simulate the propagation of the primary explosion shock wave and multi-period bubble pulsations. To verify the efficiency and accuracy of the present model, comparisons with experimental data are performed, showing that both the dynamic behaviors of oscillating bubbles and the pressure profiles of primary shock waves, bubble pulsations, and jetting loads are highly consistent. In addition, it is found that the EFEM model can satisfactorily reproduce the complex characteristics of interacting bubbles, such as the coalescence and splitting that occur during later pulsating cycles in bubbles. On this basis, the effects of the initial bubble–bubble distance γbb and buoyancy parameter δ on the features of bubble interactions and the corresponding pressure loads in the flow field are analyzed and discussed. In particular, the pressure induced by two identical UNDEX bubbles (each generated by detonation of an explosive with weight W) is compared to that induced by a single bubble generated by an explosive with weight W or 2W to provide the basic technical support and reference for the design of multiple-weapon attacks in military engineering applications. [ABSTRACT FROM AUTHOR]

In this paper, we establish a fluid-structure interaction (FSI) model to investigate the dynamic interactions between the underwater explosion (UNDEX) shock wave and a movable sphere near the free surface. We utilize the local discontinuous Galerkin (LDG) method to capture the propagation of the shock wave in the fluid domain and employ the pressure cutoff model to calculate cavitation effects. The fluid elements at the fluid-structure interface are directly coupled to the structural dynamic model, and the structural transient dynamic responses are coupled with fluid acoustic pressure at the fluid-structure interface in the governing equation. The validity of the present FSI model is verified by comparing with the continuous Galerkin method. Due to the advantage of the LDG method in capturing the discontinuous wave, the present model shows better properties than the traditional coupled acoustic-structural model. With the present FSI model, we investigate the interaction between the UNDEX shock wave and a submerged and floated sphere. Under the combined effects of the free surface and structure, the UNDEX shock and cavitation loading characteristics are analyzed, and the influences of complicated cavitation effects on dynamic responses of the sphere are discussed. [ABSTRACT FROM AUTHOR]

The interaction of an oscillating bubble and a nearby liquid–liquid interface is a complex multiphase problem that has many potential applications. In this work, the behavior of a bubble initially between two different liquids (i.e., with a stand-off distance of zero) is investigated numerically and is shown to exhibit a high degree of nonlinearity. A numerical model based on an Eulerian finite-element method is established. It is validated by simulating a nonspherical collapse of a bubble in the gravity field and comparing the results with those obtained in the experiment. Then, several cases of interaction between an oscillating bubble and a liquid–liquid interface are simulated with different initial conditions. It is confirmed that the density interface tends to induce the bubble to develop a jet that drills into the heavier liquid during the bubble collapse phase. The nondimensional period of oscillation increases with increasing density ratio of the two liquids, and an annular jet impacts, generating a pressure peak, when the density ratio exceeds 1.5. When the effect of gravity is taken into account, it is found that the annular impact is enhanced while the downward jet is weakened. In addition, a significantly sized bubble is split from the main bubble by the impact of the annular jet. When the buoyancy parameter exceeds a threshold value, gravity comes to dominate the bubble motion, and neither an annular jet nor a downward jet will develop. If the buoyancy parameter is large enough, the bubble migrates upward and detaches from the liquid–liquid interface during the collapse phase. [ABSTRACT FROM AUTHOR]

Nonlinear interaction and coalescence features of oscillating bubble pairs are investigated experimentally and numerically. The spark technique is used to generate in-phase bubble pairs with similar size and the simulation is performed with the compressible volume of fluid (VOF) solver in OpenFOAM. The initial conditions for the simulation are determined from the reference case, where the interbubble distance is sufficiently large and the spherical shape is maintained at the moment of maximum volume. Although the microscopic details of the coalescing behaviors are not focused, the compressible VOF solver reproduces the important features of the experiment and shows good grid convergence. We systematically investigate the effects of the dimensionless interbubble distance γ (scaled by the maximum bubble radius) and define three different coalescing patterns, namely, coalescence due to the expansion in the first cycle for γ < 1.1 (Pattern I), bubble breaking up and collapsing together with coalescence at the initial rebounding stage for 1.1 < γ < 2.0 (Pattern II), and coalescence of the rebounding toroidal bubbles for 2.0 < γ < 3.65 (Pattern III). For Pattern I, prominent gas flow and velocity fluctuation can be observed in the coalescing region, which may induce the annular protrusion in the middle of the coalesced bubble. For Patterns II and III, migration of the bubbles toward each other during the collapsing and rebounding stages greatly facilitates the bubble coalescence. [ABSTRACT FROM AUTHOR]

In this study, we establish a full coupling model (FCM) to simulate strong bubble-sphere interactions based on a three-dimensional boundary integral method. Different from the conventional loose coupling model (LCM), FCM adopts several auxiliary functions to deal with the mutual dependence between the hydrodynamic force and the sphere acceleration. In addition, the weighted moving least square method, a mesh density control scheme and an adaptive mesh refinement scheme are implemented to improve the quality of mesh on the deformable bubble surface. To validate the present model, convergence tests on different mesh sizes and time steps are conducted at first. The numerical results are also compared with the axisymmetric model, in which consistent results have been achieved. We further make comparisons between the numerical results and those from several experiments under different boundary conditions. For weak interaction cases, both LCM and FCM can give the results that have good agreement with the experiment data. As the interaction effects become stronger, the advantage of the FCM over the LCM becomes increasingly obvious. Particularly, when the pulsating bubble is in contact with the sphere surface, the essential physical features of the experiments can be well reproduced by the FCM while the predictions by the LCM are significantly different from the experiment. The present 3D model can be further extended to study more complex underwater contact explosions, cavitation inception on a structure and airgun bubble dynamics. • A full coupling model is established to simulate strong bubble-sphere interaction based on 3D boundary integral method. • Auxiliary functions are introduced to deal with the mutual dependence between the force and the sphere acceleration. • By using some latest numerical techniques, the interaction between a sphere and an attached bubble is simulated. • The essential physical features of some experiments are well reproduced by the present 3D model. [ABSTRACT FROM AUTHOR]

Background and Purpose: The constitutive androstane receptor (CAR), a known xenobiotic sensor, plays an important role in drug metabolism by regulating numerous genes. The polycyclic aromatic hydrocarbon pyrene, an environmental pollutant, is a CAR activator and induces mouse hepatotoxicity via CAR. Here, we investigate the molecular mechanisms of the inflammatory response in pyrene-caused mice liver injury.Experimental Approach: Effects of pyrene on the liver were investigated in wild-type and CAR knockout (KO) mice. Levels of pyrene and its urinary metabolite were analysed by high performance liquid chromatography (HPLC). Inflammatory responses were measured by qRT-PCR, western blotting, and ELISA for cytokines.Key Results: Serum amyloid A proteins (SAAs) were markedly increased in the liver and serum of pyrene-exposed wild-type mice. IL-17-producing helper T cells (Th17 cells) and IL-17 levels were increased in the liver of pyrene-exposed wild-type mice. Hepatic mRNA levels of inflammatory cytokines including IL-1β, IL-6 and TNFα, and serum IL-6 levels were significantly elevated in pyrene-treated wild-type mice. However, these changes were not observed in CAR KO mice.Conclusion and Implications: CAR plays a crucial role in pyrene-caused mice liver inflammatory response with increased SAAs and Th17 cells. Our results suggest that serum SAAs may be a convenient biomarker for early diagnosis of liver inflammatory response caused by polycyclic aromatic hydrocarbons, including pyrene. CAR and Th17 cells may be potential targets for novel therapeutic strategies for xenobiotic-induced liver inflammation. [ABSTRACT FROM AUTHOR]

The strong bubble interactions and bursting behaviors near a free surface are studied numerically with a compressible two-phase flow solver. The interface is captured by the volume of fluid method. We investigate the effects of the dimensionless distance between the bubble and the free surface γf (scaled by the maximum bubble radius) ranging from 0.25 to 1.5. For the nonbursting cases, the essential evolution of the toroidal bubble is well captured, including the splitting, coalescence, and recollapse. Generally, a relatively thin spike is generated at the free surface during the first cycle of the bubble. Subsequently, a wider secondary spike at the base of the first spike is formed during the second bubble cycle, which leads to the formation of the crown-shaped spike. When γf is sufficiently small, the bubble bursts at the free surface and an opening cavity is generated. The pressure inside the cavity and the atmospheric pressure are not balanced immediately, and the pressure difference lasts for a while, causing the inward gas flow and the final closure of the cavity. The gas flow is found to play a vital role in the bubble bursting behaviors, which has not been well understood. By comparing with previous studies, three distinct bursting patterns are identified and discussed. [ABSTRACT FROM AUTHOR]

Primary central nervous system lymphoma, a rare primary intracranial tumor, is highly malignant and usually associated with poor prognosis. Recent years, owing to the remarkable progress in intervention techniques, survival time reported has been significantly prolonged. Strategies targeting alleviation and remission are primarily depended on the early diagnosis. However, due to the heterogeneity of the clinical symptoms and imaging features, the disease is frequently misdiagnosed especially in the early phase, rendering a delay of optimal treatment. Herein, we reported the case of a 61-year-old man who was initially misdiagnosed as demyelinating encephalopathy. MRI images showed multifocal lesions across the cerebral cortex and deep white matter, which are not strengthened on contrast enhancements. In respect of clinical symptoms, no significant progress was observed over about 11 months. Finally, the diagnosis was revealed by brain biopsy. After reviewing all the images of the patient, we found that the corpus callosum was involved early in the course of the disease. Therefore, for multifocal intracranial lesions involving the corpus callosum, we should always be vigilant about the possibility of primary central nervous system lymphoma. Histopathological examination of brain biopsy is helpful for early definitive diagnosis. [ABSTRACT FROM AUTHOR]

A high-speed liquid jet is commonly observed during the collapse phase of a cavitation bubble. In this letter, we present a surprising counter-jet (directed away from the nearby boundary) that forms in the early expansion phase of the bubble near a curved elastic boundary, which has not been reported before. The boundary integral simulation reveals the most possible mechanism as follows: First, the expansion of the bubble causes a local concave deformation on the boundary. Thereafter, the bubble partly envelops the curved elastic boundary, leading to the confinement of some liquid in a local dent. During the deformation recovery, a localised high pressure region is built up within the narrow dent, which drives a thin liquid jet away from the boundary. [ABSTRACT FROM AUTHOR]

Abstract Underwater explosion in free field is investigated in this paper numerically. With the multiphase interface captured by the Volume of Fluid (VOF) method, the Eulerian finite element method (EFEM) for underwater explosion is established. The MUSCL algorithm to advect the element centered variables is modified to maintain its conservativeness in the axisymmetric model, and the second order Early Time Approximation (ETA 2) is adopted to deal with the non-reflecting boundary condition of the computational domain. By comparing with the experiment results, the numerical model is proved in both shockwave and bubble oscillation simulation. With the numerical model, 2 underwater explosion cases with different initial depths are simulated and the near-field pressure characteristics are analyzed. The near-field bubble pulsation load exhibits noteworthy asymmetry around the bubble, which is attributed to the 2 high pressure regions above and beneath the bubble, respectively. By comparing the evolution of bubbles with different buoyancy parameters, it is found that the increase of the buoyancy parameter can delay the penetration and extend the collapse of the bubble. Highlights • The present numerical model can predict both the shockwave and bubble pulsation load with good accuracy. • The non-reflecting boundary condition based on ETA2 works well in the underwater explosion simulation. • The MUSCL algorithm is modified for the convection in the axisymmetric model. • The asymmetry of the pulsation load is generated by the 2 high pressure regions caused by gravity and the jet impact. [ABSTRACT FROM AUTHOR]

This study aims to elucidate the complex interaction between a suspended particle and an attached bubble, which is associated with cavitation in silt-laden flow. Systematic experiments are performed with high-speed photography, in which bubbles are generated by underwater electric discharge means. The bubble-particle interactions are found to be strongly dependent on two dimensionless parameters, i.e., the particle-bubble size ratio λL and the particle-liquid density ratio λρ. When λρ equals 2.61, the bubble split phenomenon is universally observed and the particle shooting effect (the particle acceleration during bubble expansion and after bubble-particle detachment) becomes more obvious as λL decreases. If λL < ∼0.34, the particle velocity keeps positive (away from the bubble), otherwise the particle velocity drops below zero (toward the bubble) during the bubble collapse phase. As λρ increases, the particle achieves a lower velocity but a higher impulse, and the bubble necking phenomenon is more pronounced. Our boundary integral simulations reproduce the experiments extremely well, including the particle dynamics, the bubble wrapping the particle, the bubble necking and detachment, and the mushroom-shaped bubble. After the bubble-particle detachment, the liquid around the detachment location is drawn inward and collides on the axis of symmetry, leading to the formation of a localized high pressure region between the bubble and the particle, which accelerates the particle for the second time even in the bubble collapse phase. [ABSTRACT FROM AUTHOR]

We found CRC is sensitive to cuproptosis which also results in IFN-γ-inducible PD-L1 upregulation in tumor cells. A cuproptosis-mediated immunotherapy nanoreactor is constructed for CRC treatment. It not only significantly induces cuproptosis in cancer cells, but also initiates cuproptosis-mediated systemic immune responses, reshapes immunosuppressive TME and prevents immune evasion, further inhibiting both primary and distant tumor growth. [Display omitted] Owing to the deficiency of infiltrating immune cells and the accumulation of immunosuppressive cells in tumor microenvironment (TME), immunotherapy remains enormous challenges in colorectal cancer (CRC). Here, CRC was found to be sensitive to cuproptosis which could further evoke immune responses and mediate immune resistance. Thus, a cuproptosis-mediated immunotherapy nanoreactor (CCJD-FA) was constructed by encapsulating copper-based shell-coated CaO 2 and bromodomain-containing protein 4 inhibitor JQ-1 with DSPE-PEG-FA. Within tumor cells, CCJD-FA was disassembled under GSH environment, and the exposed CaO 2 could generate H 2 O 2 under the acidic condition, which reacted with the released Cu2+ via Fenton-like reaction to produce O 2 for relieving hypoxia and Cu+ for inducing cuproptosis. Furthermore, CCJD-FA could also inhibit intracellular glycolysis and ATP generation, then blocking the Cu+ efflux protein ATP7B. Meanwhile, the IFN-γ-induced PD-L1 expression could be exactly reduced by the BRD4 suppression and oxygen supply. These effects sensitized cancer cells to cuproptosis, further evoking systemic immune responses and reshaping immunosuppressive TME to inhibit tumor growth. [ABSTRACT FROM AUTHOR]

Two-bubble interaction is the most fundamental problem in multi-bubbles dynamics, which is crucial in many practical applications involving air-gun arrays and underwater explosions. In this paper, we experimentally and numerically investigate coalescence, collapse, and rebound of non-buoyant bubble pairs below a rigid wall. Two oscillating vapor bubbles with similar size are generated simultaneously near a rigid wall in axisymmetric configuration using the underwater electric discharge method, and the physical process is captured by a high-speed camera. Numerical simulations are conducted based on potential flow theory coupled with the boundary integral method. Our numerical results show excellent agreement with the experimental data until the splashing of the jet impact sets in. With different ranges of γbw (the dimensionless distance between the rigid wall and the nearest bubble center), the interaction between the coalesced bubble and the rigid wall is divided into three types, i.e., “weak,” “intermediate,” and “strong.” As γbw decreases, the contact point of the two axial jets migrates toward the wall. In “strong interaction” cases, only an upward jet towards the upper rigid wall forms and a secondary jet with a larger width appears at the base of the first jet. The collapsing coalesced bubble in a toroidal form splits into many smaller bubbles due to the instabilities and presents as bubble clouds during the rebounding phase, which may lead to a weakened pressure wave because the focusing energy associated with the collapsing bubble is disintegrated. [ABSTRACT FROM AUTHOR]

The present work is dedicated to the enhancement and application of the recently developed δ + -SPH scheme for two and three dimensional water entry problems. The cylinder surface presents a circular shape and therefore the position where the flow separation happens is tightly related to the implementation of the boundary condition. A special treatment for the particle shifting between fluid and solid wall is highlighted. Adaptive particle refinement (APR) is applied in this work to reduce the computational cost. It is found that, APR and the δ + -SPH scheme benefit to each other. That is to say the former reduces the computing cost of the latter while in return the latter solves the problem of particle disorder of the inactive particles of the former. Thanks to the combination of APR and δ + -SPH especially in three dimensional (3D) cases, the overall computational cost is significantly reduced while sufficiently fine particle resolution can be obtained in the flow region characterized by large pressure gradient close to the structure surface. The fairly good agreements between the SPH results and the experimental data prove the present SPH model to be a reliable tool in accurately solving the fluid–structure interacting problems in ocean engineering. [ABSTRACT FROM AUTHOR]

The use of a dual palladium/organic photoredox catalytic system enables the directed arylation of arenes with aryldiazonium salts with a broad substrate scope at room temperature under mild reaction conditions. This study thus serves as not only an alternative route for the biaryl motifs but also a new example for the application of an organic photoredox catalyst. [ABSTRACT FROM AUTHOR]

A photoredox catalytic method has been developed for the direct C2 alkylation of pyridine N-oxides. This reaction is compatible with a range of synthetically relevant functional groups for providing efficient synthesis of a variety of C2-alkylated pyridine N-oxides under mild conditions. Mechanistic studies are consistent with the generation of a radical intermediate along the reaction pathway. [ABSTRACT FROM AUTHOR]

The determination of the dynamic active sites over binary oxide catalysts is of great challenge in heterogeneous catalysis. In this work, the origin of active sites toward low-temperature CO oxidation (<200 °C) were thoroughly studied using MnO x -CeO 2 composite oxide catalysts with different Mn/Ce molar ratios, synthesized by a redox co-precipitation method. The optimum Mn 1 Ce 1 catalyst (T 100 = 190 °C), which showed excellent activity, has found to be composed of three phases: (1) CeO 2 ; (2) amorphous MnO x ; (3) MnO x -CeO 2 solid solution (active sites). With the combination of kinetics and characterization results, including Temperature-Programmed-Desorption/Reduction (TPD/TPR), operando Raman spectroscopy and in situ diffuse reflectance infrared Fourier transform spectra (DRIFTS), the dynamic structures of catalysts were rationalized with the identification of the interface of MnO x and CeO 2 . The mechanism for CO oxidation over MnO x -CeO 2 in the temperature range 100–190 °C were proposed that the direct and the formate routes were followed at T < 130 °C, and the carbonate route became dominant at T > 130 °C. Notably, the Mars-van Krevelen mechanism was proceeded in the whole temperature range. We speculate that cheap binary oxides will substitute for noble metal as catalysts for the removal of CO and other toxic gases, especially operating under mild conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] Activation of the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway could effectively initiate antitumor immunity, but specific activation of STING pathway is still an enormous challenge. Herein, a ferroptosis-induced mitochondrial DNA (mtDNA)-guided tumor immunotherapy nanoplatform (designated as HBMn-FA) was elaborately developed for activating and boosting STING-based immunotherapy. On the one hand, the high-levels of reactive oxygen species (ROS) in tumor cells induced by HBMn-FA-mediated ferroptosis elicited mitochondrial stress to cause the release of endogenous signaling mtDNA, which specifically initiate cGAS-STING pathway with the cooperation of Mn2+. On the other hand, the tumor-derived cytosolic double-stranded DNA (dsDNA) from debris of death cells caused by HBMn-FA further activated the cGAS-STING pathway in antigen-presenting cells (e.g., DCs). This bridging of ferroptosis and cGAS-STING pathway could expeditiously prime systemic antitumor immunity and enhance the therapeutic efficacy of checkpoint blockade to suppress tumor growth in both localized and metastatic tumor models. The designed nanotherapeutic platform paves the way for novel tumor immunotherapy strategies that are based on specific activation of STING pathway. [ABSTRACT FROM AUTHOR]

In numerical simulations of fluid dynamics based on the smoothed particle hydrodynamics (SPH) method, the formula for the viscosity term is always complicated since it is a second-order derivative term. In this paper, for Newtonian fluids, a novel formula for the viscous force satisfying the Stokes hypothesis is proposed in the weakly compressible framework. Because of the ease of adopting only a single layer of particles to enforce the boundary condition, the normal flux method is implemented for a solid wall boundary, which should be suitable for complex geometries and thin structures. The normal flux method can mitigate the decrease in numerical accuracy caused by the lack of neighbouring particles at the boundary. Meanwhile, the kernel function at the boundary is modified to satisfy the normalization condition. The accuracy and robustness of the proposed algorithm are verified by a series of cases of numerical fluid simulations, paving the way for SPH simulations coupled with complex thin shell structures for fluid–structure interaction problems. • A novel viscous force that satisfies Stokes hypothesis is derived. • The viscous force near the single-layer boundary is presented. • Kernel function correction technique is proposed to ensure consistence near the single-layer boundary. [ABSTRACT FROM AUTHOR]

A photoredox catalytic method was developed for the direct cyanation of alkyltrifluoroborates. This reaction provides a new and useful transformation of the easily available alkyltrifluoroborates. The photocatalytic reaction can tolerate a variety of functional groups with mild reaction conditions. Mechanistic investigations are consistent with the present reaction following a radical pathway. [ABSTRACT FROM AUTHOR]

In the current study, an improved numerical model is proposed in the compressible fields based on Smoothed Particle Hydrodynamics (SPH), which is comprised of MUSCL interpolation in multiphase flow, enhanced particle regeneration technique (PRT) and the particle shifting technique (PST) in compressible flows. The PRT is specially proposed to deal with compressible problems, in which the volume of particles have large variation during the whole simulation process. Different to the conventional PRT [1] , an interface control (IC) method is proposed to deal with the mass conservation problem which may result in the unphysical movement of interface when modeling multifluids. The multiphase MUSCL interpolation aims at dealing with over-dissipation problem that exists in the Godunov-type SPH which may result in the wrong detection of wave front. To avoid large discontinuity between different fluids, two kinds of extrapolation schemes (constant extrapolation and isentropic extrapolation) are discussed and compared at the inspiration of the ghost fluid method (GFM). The proposed MUSCL-based compressible SPH model is validated and discussed in several challenging test cases, such as multiphase shock tube like problem, the shock wave impacting on multifluids interface problem and Richtmyer-Meshkov instability etc., in which good agreements are obtained. • An enhanced particle regeneration technique is proposed to simulate compressible multiphase flows based on SPH. • The mass conservation property is improved leading to the accurate detection of multiphase interface. • The wave front can be better predicted and higher resolution results are obtained combined with MUSCL scheme. • The strongly compressible shock tube problem and the shock wave impacting on the multiphase interface problem is simulated. [ABSTRACT FROM AUTHOR]

Bemisia tabaci is an important agricultural pest with worldwide distribution and host preference. Therefore, understanding the biology of this pest is important to devise specific pest control strategies. The antennae of herbivorous insects play an important role in the identification of hosts using plant volatiles. To understand the features of antennae in B. tabaci MEAM 1(formerly known as biotype ‘B’) and MED (formerly known as biotype ‘Q’), the morphology and distribution of the antennal sensilla were examined using scanning electron micrographs. The results showed that the average antennae length in MEAM 1 was longer than MED. No differences were observed in the number and distribution of antennal sensilla in MEAM 1 and MED antennae; each antenna had nine different types of sensilla. Both cryptic species possessed Microtrichia, Grooved surface trichodea sensilla, Chaetae sensilla, Coeloconic sensillaⅠandⅡ, Basiconic sensilla Ⅰ, Ⅱ and Ⅲ and Finger-like sensilla. This is the first report of Grooved surface trichodea sensilla and Basiconic sensilla Ⅱ on B. tabaci flies. The numbers of Chaetae sensilla were different in the females and males of MEAM 1 and MED, which females having 5 and males containing 7. The surface structure of Basiconic sensilla Ⅰ was different with MEAM 1 showing a multiple-pitted linen surface and MED showing a multiple-pitted pocking surface. Basiconic sensillaⅡ were double in one socket with the longer one having a multiple-pitted surface and the shorter one with a smooth surface. Basiconic Ⅲ and Finger-like sensillae were longer in MEAM 1 antennae than in MED antennae. Our results are expected to further the studies that link morphological characteristics to insect behavior and help devise strategies to control insect pests. [ABSTRACT FROM AUTHOR]

A hydroelastic fluid–structure interaction (FSI) solver entirely based on the Riemann-SPH method is proposed. In this scheme, the Riemann-SPH method is incorporated to model elastic structures, which is performed by proposing a new treatment on Cauchy stress. The present structure solver can avoid the use of the artificial viscous force and can obtain good results. For the fluid, the conventional Riemann-SPH with a low-dissipation limiter is adopted to simulate incompressible free surface flows. The structure solver is coupled with the fluid solver by a simple coupling way considering the force balance. The developed structure solver is verified by three benchmarks, namely a free oscillating cantilever plate, stress concentration problem of a plate and wave propagation in a cable. Subsequently, through several 2D and 3D typical hydroelastic FSI tests, the accuracy and robustness of the present FSI solver are verified/validated by comparing with analytical solutions and experimental results. • The Riemann-SPH method is incorporated to be an elastic structure solver. • A unified hydroelastic FSI solver based on the Riemann-SPH method is proposed. • The present FSI solver can reproduce typical FSI problems with superior accuracy. [ABSTRACT FROM AUTHOR]

Cu 2 ZnSnS 4 (CZTS) is a complex quaternary compound semiconductor, it is easy to form secondary phases during preparation, like Cu 2 S and ZnS, and there are interfaces between these secondary phases and the matrix. The interfaces are also key factors in determining the photovoltaic performance of CZTS. So, we used the first-principles calculation method to research the interfaces between the secondary phase Cu 2 S, ZnS and CZTS thin films. The influence of the secondary phase is clarified by analyzing the interface electronic properties of secondary phase and CZTS. The existence of Cu 2 S secondary phase is harmless to the photovoltaic performance of CZTS, and can even promote the improvement of photovoltaic performance. Therefore, it is not necessary to avoid it when preparing CZTS films, and even it can be used. However, the existence of ZnS secondary phase is harmful to the photovoltaic performance of CZTS, which should be avoided when preparing CZTS films. • Two secondary phases in CZTS have been investigated by DFT calculations. • The influence of the secondary phase is clarified by analyzing the interfacial properties. • Cu2S secondary phase is harmless for the PV performance of CZTS. • ZnS secondary phase has detrimental effect for the PV performance of CZTS. [ABSTRACT FROM AUTHOR]

Leptin treatment reverses hyperglycemia in animal models of poorly controlled type 1 diabetes (T1D), spurring great interest in the possibility of treating patients with this hormone. The antidiabetic effect of leptin has been postulated to occur through suppression of glucagon production, suppression of glucagon responsiveness or both; however, there does not appear to be a direct effect of leptin on the pancreatic alpha cell. Thus, the mechanisms responsible for the antidiabetic effect of leptin remain poorly understood. We quantified liver-specific rates of hepatic gluconeogenesis and substrate oxidation in conjunction with rates of whole-body acetate, glycerol and fatty acid turnover in three rat models of poorly controlled diabetes, including a model of diabetic ketoacidosis. We show that the higher rates of hepatic gluconeogenesis in all these models could be attributed to hypoleptinemia-induced activity of the hypothalamic-pituitary-adrenal (HPA) axis, resulting in higher rates of adipocyte lipolysis, hepatic conversion of glycerol to glucose through a substrate push mechanism and conversion of pyruvate to glucose through greater hepatic acetyl-CoA allosteric activation of pyruvate carboxylase flux. Notably, these effects could be dissociated from changes in plasma insulin and glucagon concentrations and hepatic gluconeogenic protein expression. All the altered systemic and hepatic metabolic fluxes could be mimicked by infusing rats with Intralipid or corticosterone and were corrected by leptin replacement. These data demonstrate a critical role for lipolysis and substrate delivery to the liver, secondary to hypoleptinemia and HPA axis activity, in promoting higher hepatic gluconeogenesis and hyperglycemia in poorly controlled diabetes. [ABSTRACT FROM AUTHOR]

Numerical simulation for fluid flow over an attached rigid body with a deformable ring bubble is analyzed based on the velocity potential theory together with the boundary element method (BEM). The analysis is focused on the axisymmetric case. The bubble surface is treated as a well defined air-liquid interface and is tracked by a mixed Eulerian-Lagrangian method. The points of intersection between the bubble and body are treated, specially in the numerical procedure. The auxiliary function method is adopted to calculate the pressure on the body surface and in the flow field. The convergence study is undertaken to assess the developed numerical method and the computation code. Some case studies are undertaken in which the interactions between the bubble/body and the incoming flow field are simulated. The effects of various physical parameters on the interactions are investigated. [ABSTRACT FROM AUTHOR]

Abstract: Numerical and experimental methods are combined in this paper to study the bubble dynamics generated by an underwater charge explosion with different initial charge shape, detonating styles and boundary conditions. Outdoor experiments are carried out to employ sunlight with the assistant of lamplight to get clearer pictures of bubble motion. The results show that the charge detonating stage is not finished instantly but takes some time to explode fully. The explosion begins from its detonating end and finishes at the other end, which results in its uneven distribution of initial normal velocity. So instead of following the traditional method of treating the charge explosion instantly, a real charge explosion model is built in this paper with the combination of LS-DYNA and the boundary element method (BEM). LS-DYNA is used to solve the charge initial detonation and the BEM to solve its subsequent bubble motion. The linking relationship between these two methods is modeled. The convergence study has been firstly taken with different meshes. In this paper, charges with a different slenderness ratio from 0.99 to 20 are chosen to carry out the experiments and their corresponding numerical results are put forward. It can be found in both experimental and numerical results that the initial charge shape and its detonating style would affect its following bubble dynamic behavior. When the cylindrical charge is horizontally installed and end detonated, an oblique jet leaned to the detonating end would be formed and a horizontal migration process is also observed during the whole bubble pulsating stage. The bubble dynamic behaviors near different solid boundaries are further studied and the numerical results coincide well with the experimental ones. [Copyright &y& Elsevier]

In this paper, the behavior of a bubble near a rigid cylinder is studied experimentally as the positions of bubble induction change, and several cylinders with different diameters are used in the experiment. The main results are as follows. The behavior of a bubble near a rigid cylinder is distinct from that near a rigid plate. When the cylinders are laid in deep water, there will occur three kinds of typical bubble shapes as the distance between bubble and cylinder increases. And the bubble shapes are different as the diameter of cylinder varies. When the cylinders are laid near a free surface, the behaviors of bubble near cylinders with different diameters are similar. For a certain distance between bubble and free surface, as the distance between bubble and cylinder increases, 'double jet', 'inclined jet' and 'downward jet' will take place successively. [ABSTRACT FROM AUTHOR]

Abstract: Damaged ship at sea will be a direct threat to lives and property, and it has a great significance of studying ship's remaining buoyancy, stability, sinking time and other important parameters. The process of a damaged ship sinking into water is a complex motion involving ship hull, inner and outer fluid coupled with waves and many other factors. It is featured by high nonlinearity and hard to establish a precise theoretical model to study. Yet SPH (smoothed particle hydrodynamics) as a meshfree method has a great advantage in solving such problems because of the nature of self-adaptive and Lagrangian. Firstly, the experiments of two scaled ship models with different openings sinking into water are carried out, through the sinking processes of broadside opening and bottom opening models, the conclusion is drawn that although the serious loss of stability of broadside opening model, the sinking time and other parameters are more conducive to rescue after maritime distress. Secondly, the parallel program of three dimensional SPH is developed to simulate the above more complex model, broadside opening model. The coupled process of sloshing is compared with that of experiment, and the results show good agreement with each other which verify the accuracy and feasibility of three dimensional parallel program. [Copyright &y& Elsevier]

As the most prominent proton pumps in plants, vacuolar H+-ATPases (VHAs) comprise multiple subunits that are important for physiological processes and stress tolerance in plants. However, few studies on the roles of subunit genes of VHAs in chrysanthemum have been reported to date. In this study, the gene of A subunit of V-ATPase in chrysanthemum (CmVHA-A) was cloned and identified. CmVHA-A was conserved with VHA-A proteins from other plants. Expression analysis showed that CmVHA-A was highly expressed in most tissues of chrysanthemum except for the flower bud, and was readily induced by polyethylene glycol (PEG) treatment. Functional analysis demonstrated that CmVHA-A exerted a negative influence on the growth and development of shoot and root of chrysanthemum under normal conditions. RNA-sequencing (RNA-seq) analysis revealed the possible explanations for phenotypic differences between transgenic and wild-type (WT) plants. Under drought conditions, CmVHA-A positively affected the drought tolerance of chrysanthemum by enhancing antioxidase activity and alleviating photosynthetic disruption. Overall, CmVHA-A plays opposite roles in plant growth and drought tolerance of chrysanthemums under different growing conditions. • Under normal conditions, CmVHA-A exerted a negative influence on the growth of shoot of chrysanthemum. • RNA-seq analysis revealed CmVHA-A involved in the metabolism of energy and carbohydrates of chrysanthemum. • Under drought conditions, CmVHA-A positively affected the drought tolerance of chrysanthemum. [ABSTRACT FROM AUTHOR]