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Lead rubber bearing (LRB) may be subjected to low temperature effect and superstructure weight when it was used in the cold regions, which will affect the durability of the bearing. To investigate the performance degradation of the LRB under combination of low temperature cycles and superstructure weight, five specimens were designed to conduct 0, 20, 40, 60, 80, and 100 low temperature cycles while maintaining super load of 0, 4, 7, 10, and 12 MPa. The use of ultra low temperature and ordinary temperature room to simulate the environment of low temperature effect and the specimen was kept under compression to simulate superstructure weight. The degradation of the mechanical properties of LRB was analyzed by conducting vertical compression tests and horizontal shear tests on the specimens. The results show that the vertical compression stiffness, equivalent horizontal stiffness, post-yield stiffness, yield force, and equivalent damping ratio of LRB show a decreasing trend under the low temperature cycles and superstructure weight. With the increase of superstructure weight, the degradation of equivalent horizontal stiffness is aggravated, the equivalent damping ratio does not degenerate, and the degradation of post-yield stiffness and yield force is weakened. Finally, the least squares method is used to analyze the change of its horizontal shear performance and give the degeneration curve and degeneration function for 50 years. The degradation curve of the horizontal shear performance of LRB is basically in the form of an exponential function. [ABSTRACT FROM AUTHOR]

Shallow mixing layers developed in partially-distributed canopy flows (PCFs) are important for water conveyance, sediment transport and solute dispersion. In this paper, we address the response of shallow mixing layers in PCFs to several influential factors associated with bed friction, water shallowness and canopy denseness using depth-averaged Large Eddy Simulation (DA-LES). The results show that under certain canopy denseness, shallow mixing layers in PCFs display asymptotic behaviour for the variation of bed friction and water shallowness, consistent with classic shallow mixing layers. The canopy drag encourages the asymmetric growth of the inner and outer parts of the mixing layer, and this effect decreases when bed friction and water shallowness become pronounced. Characteristic velocity and length scales show similarity well delineated by exponential decay function regarding a stabilization efficiency parameter. The exception happens for the inner length scale of the mixing layer when only changing canopy density. We conclude that changing the canopy denseness can encourage the overall shift of mixing layer scaling regarding a broad range of bed friction and water shallowness. Furthermore, the bed friction parameter thresholding triggering flow instability of mixing layers in PCFs is found about 0.03, lower than 0.09 for splitter-plate induced mixing layers. [ABSTRACT FROM AUTHOR]

The earthquake usually causes multi-dimensional vibration for the large span grid structure, how to effectively isolate and mitigate the vibration response of structure is an important problem in engineering. In this paper, a novel viscoelastic bio-inspired multi-dimensional vibration isolation (VBM-VI) device is proposed under the inspiration of bionic design of the bird legs, which possesses multi-dimensional vibration isolation performance by constituting of viscoelastic core pad and VE-LLS device together. The property experiment of the VBM-VI device is performed to explore the mechanical performance at vertical and horizonal directions, the hysteretic curves and characteristic parameters are discussed to reveal the influence of the excitation frequency and amplitude on the mechanical properties of the VBM-VI device, the experimental results show that the mechanical properties express significant frequency and amplitude dependence at vertical and horizontal directions. To further describe the mechanical proprieties of the VBM-VI device, the mathematical models are established at vertical and horizontal directions respectively, and the comparison analysis between experimental and theoretical results indicates that the established mathematical models can precisely describe mechanical performance of the VBM-VI device. [ABSTRACT FROM AUTHOR]

Based on the low cost and superior damping performance of viscoelastic dampers, the new structural system strengthened with viscoelastic energy dissipation braces (VEDB) is proposed to upgrade the reinforced concrete frame structures with insufficient seismic capability. For the dynamic performance researches and damage evolution predictions of this structure system during earthquakes, the dynamic performance of six RCFs (reinforced concrete frames) and six VEFs (another six special reinforced concrete frames with VEDB) are studied under sinusoidal wide frequency range loading excitation horizontally. On this basis, the qualitative and quantitative relations on the damage growing at the material-level and the member-level performance deteriorating about the frame structures are conducted. Furthermore, the empirical calculation model on the cross-level damage evolution of VEFs are established and verified. Finally, a set of useful and robust cross-level judgment criteria for damage performance rates is proposed. The research found that, the installation of VEDB can significantly improve the load bearing capacity, the lateral stiffness and the energy dissipation capacity of the structures. The damage pattern of the structures is improved by VEDB, and it ensures the design criteria of "strong joints and weak members." The empirical calculation model on the cross-level damage evolution and judgment criteria for damage performance rates proposed in this paper are useful and stable in practical engineering. [ABSTRACT FROM AUTHOR]

The hubless rim-driven thruster (RDT) has become increasingly interesting for ship propulsion. Gap flow has been proven as the main feature of RDT that cannot be simply neglected. In this study, based on a classical hubless RDT, the effects of the gap geometry are studied by adjusting its axial passage length, and inlet and outlet oblique angles. The hydrodynamic characteristics of the RDT were simulated with OpenFOAM based on the k -- ω shear stress transport turbulence model. Due to the pressure increase after the main flow passes through the rotating blades, the flow inside gap is driven upstream, which is opposite to the main flow direction. It is found that the hydrodynamic efficiency is increased as the gap axial passage length is shortened, which is realized by increasing the oblique angle with the fixed inlet and outlet positions. Moving the inlet and outlet to further downstream and upstream positions has negligible effects on the hydrodynamic efficiency and leads to recirculating flow within the gap near its inlet. These findings shed light on the design of the gap geometry to improve the RDT hydrodynamic performance. [ABSTRACT FROM AUTHOR]

The investigation of association between board diversity and the firm performance is the subject of many studies. However, the empirical results presented in the extant literature are inconclusive at best. The inconclusive empirical results could be due to several factors and one of them could be that the relationship is contingent on some key factors. Given the rising trend of Environmental, Social and Governance (ESG) activities, in this paper the relationship between board diversity and the firm performance is tested in the context of ESG activities. The subject of examination in this study is the listed Chinese firms. The sample period spans for 6 years and is collected from 2014 to 2019. This work uses a dynamic approach to modelling relationships. The generalised method of moments (GMM) is used in a two-step system. An endogeneity-free estimate may be achieved by using this strategy. We can learn a great deal from these hypotheses. There is a positive and substantial correlation between board diversity and the firm's success, which suggests that diverse boards are beneficial to businesses. Both ESG activities and a positive coefficient on company performance are significant. This shows investors appreciate companies that are involved in ESG activities because they see this as an investment that pays off. Last but not least, the report shows that board diversity has a negative and considerable impact on ESG efforts. According to the results, board diversity and ESG efforts are not necessary for a company's success. According to the data, board diversity is not particularly beneficial in the context of significant ESG initiatives. Board diversity really hurts a company's success when it engages in high ESG activities. The study also discusses the work's policy ramifications. Finally, the work lays out a clear path for further study. [ABSTRACT FROM AUTHOR]

To expand the inclusiveness of hybrid test platform research, enhance the flexibility of hybrid test platforms using various control strategies, and promote the development of hybrid test techniques, a low-cost user-configurable electric actuator hybrid test platform is established in this paper. This platform can be transferred to other medium or large electric actuator hybrid test platform, the research applications of this platform cannot be limited by their proposed setup. Firstly, the hardware system design including hybrid test facility integrated control system core architecture and all related signal routings are carried out. Then, the improved equivalent force control feedback method based on force-loading control is proposed, and the software system development including hybrid test process control system software and user-configurable STM32 microcontroller (UCSM) software are conducted. Next, the mechanical performance of viscoelastic damper is tested, and the mechanical model parameters of viscoelastic damper are regressed. The accuracy of electric actuator force control (inner control loop), of which the control tasks get executed on the UCSM is verified using the experimental substructure of viscoelastic damper. The hybrid test of viscoelastic damping system verifies the reliability and robustness of hybrid test platform (outer control loop). Finally, the developed hybrid test platform implements various hybrid tests of viscoelastic damping system under broad temperature range and different seismic intensities. The test results reveal the influence of temperature and seismic intensities on the seismic control effect of viscoelastic damper. [ABSTRACT FROM AUTHOR]

The bionics design method has been proverbially applied at vibration control field, and how to make bionic vibration control device possess excellent mechanical property and stable energy dissipation capacity is an important subject. In this paper, a bionic viscoelastic limb-like-structure (VE-LLS) device is proposed in conjunction with the viscoelastic (VE) damper and the limb-like-structure (LLS) device together, and the proposed device simultaneously possesses excellent mechanical propriety and energy dissipation capacity. Firstly, the mechanical property test of the VE-LLS device is conducted to investigate the effect of ambient temperature, excitation amplitude and frequency on its dynamic mechanical property and energy dissipation capacity. The energy dissipation contribution caused by the LLS joint friction for the VE-LLS device is discussed. Then, the energy dissipation model of the VE-LLS device is established by simultaneously considering the viscoelastic and friction factors, and the comparison result indicates that the established energy dissipation model can accurately describe the energy dissipation capacity of the VE-LLS device under different ambient temperature, exaction amplitude and frequency. Finally, to further promote the stability of energy dissipation capacity of the VE-LLS device at different temperature and frequency, an energy dissipation compensation strategy is proposed by increasing the energy dissipation of the LLS joint friction to compensate for the energy dissipation attenuation of the VE damper caused by high temperature and low frequency, and the results shows that the compensation strategy expresses excellent effect for the energy dissipation stability of the VE-LLS device. [ABSTRACT FROM AUTHOR]

Mangrove endophytic fungi were proved to be a prolific resources for bioactive secondary metabolites. Two new polyketides, pestalotiopin B (1) and pestalotiopyrone N (2) were obtained from the ethyl acetate extracts of the rice solid cultures of the mangrove endophytic fungus Pestalotiopsis sp. HQD-6. The structures of 1 and 2 were determined by detailed interpretation of NMR spectroscopic analysis and HR-ESIMS. All of the isolates were evaluated for their antimicrobial, antioxidant and cytotoxic activities. [ABSTRACT FROM AUTHOR]

Rescheduling is a procedure to repair a production plan affected by unexpected disruptions. It is important because a production schedule released to a shop floor is subject to unexpected disruptions. This paper develops two novel heuristic rescheduling procedures, AWI-J and AWI-O, to minimise mean tardiness of jobs in a job shop. The procedures are based on an active schedule-generation procedure and Wilkerson–Irwin algorithm, which is well known for minimising mean tardiness of a schedule. The performances of the new procedures are compared with those of the Affected Operations Rescheduling (AOR) procedure, which is popular in the rescheduling literature. Efficiency measures such as mean tardiness, mean flowtime, and makespan, and a stability measure, deviation of new operation start times from the original start times, are used for comparison. Test results show that AWI-J improves efficiency over AOR, and AWI-O improves efficiency and stability as well. [ABSTRACT FROM AUTHOR]

We investigated the effect of azole antifungal drugs (ketoconazole, voriconazole, and itraconazole) on the pharmacokinetics of apatinib in rats. The rats in ketoconazole, voriconazole, and itraconazole groups received single-dose apatinib 30 mg/kg after the oral administration of ketoconazole, voriconazole, and itraconazole, respectively. Co-administration of ketoconazole or voriconazole significantly increased the apatinib Cmax and AUC(0-t) and decreased the clearance. Co-administration of itraconazole did not significantly affect the pharmacokinetics parameters of apatinib. It could be concluded that both ketoconazole and voriconazole significantly increase the exposure of apatinib, and affect the pharmacokinetics of apatinib in rat. Apatinib can be co-administered with itraconazole, but ketoconazole and voriconazole should be avoided if possible or be underwent therapeutic drug monitoring of apatinib. A further clinical study should be conducted to investigate the inhibitory effect of azole antifungal drugs on the apatinib plasma concentration. [ABSTRACT FROM AUTHOR]

Understanding the effect of liposome size on tendency for accumulation in tumour tissue requires preparation of defined populations of different sized particles. However, controlling the size distributions without changing the lipid composition is difficult, and differences in compositions itself modify distribution behaviour. Here, a commercial microfluidic format as well as traditional methods was used to prepare doxorubicin-loaded liposomes of different size distributions but with the same lipid composition, and drug retention, biodistribution and localization in tumour tissues were evaluated. The small (∼50 nm diameter) liposomes prepared by microfluidics and large (∼75 nm diameter) liposomes displayed similar drug retention in in vitro release studies, and similar biodistribution patterns in tumour-bearing mice. However, the extent of extravasation was clearly dependent on size of the liposomes, with the small liposomes showing tissue distribution beyond the vascular area compared to the large liposomes. The use of microfluidics to prepare smaller size distribution liposomes compared to sonication methods is demonstrated, and allowed preparation of different size distribution drug carriers from the same lipid composition to enable new understanding of tissue distribution in compositionally consistent materials is demonstrated. [ABSTRACT FROM AUTHOR]

In the hybrid approach of large-eddy simulation (LES) and Lighthill's acoustic analogy for turbulence-generated sound, the turbulence source fields are obtained using an LES and the turbulence-generated sound at far fields is calculated from Lighthill's acoustic analogy. As only the velocity fields at resolved scales are available from the LES, the Lighthill stress tensor, serving as a source term in Lighthill's acoustic equation, has to be evaluated from the resolved velocity fields. As a result, the contribution from the unresolved velocity fields is missing in the conventional LES. The sound of missing scales is shown to be important and hence needs to be modeled. The present study proposes a kinematic subgrid-scale (SGS) model which recasts the unresolved velocity fields into Lighthill's stress tensors. A kinematic simulation is used to construct the unresolved velocity fields with the imposed temporal statistics, which is consistent with the random sweeping hypothesis. The kinematic SGS model is used to calculate sound power spectra from isotropic turbulence and yields an improved result: the missing portion of the sound power spectra is approximately recovered in the LES. [ABSTRACT FROM AUTHOR]

Analogous to the dispersion of lamellar phase-forming lipids to form liposomes, dispersion of lipids that form alternative liquid crystalline structures, such as cubic and hexagonal phase, forms particles termed cubosomes and hexosomes, respectively. Although these particles possess alternative structural forms and hence behavior, when compared to liposomes, they have received significantly less attention in the literature. While most studies have utilized glyceride lipids to prepare nonlamellar dispersions, recent advances in identifying new materials from which to prepare these particles has broadened the interest in this field. This review focuses on the materials used to form nonlamellar dispersions and the methods used to characterize their structure. Increased awareness of their structural characteristics and hence potential benefits in applications, such as drug delivery, is hoped to stimulate further studies that will ultimately see their uptake in commercial products. [ABSTRACT FROM AUTHOR]

Chaenodraco wilsoni, a species of Channichthyidae, inhabits in southern ocean. The total length of complete mitochondrial genome of C. wilsoni is 17,432 bp, which encoded 37 genes. Similar to most Antarctic fishes, the ND6/tRNA (glu) translocation and an additional non-coding region linked with ND6 have also occurred in C. wilsoni. The ML tree supports that C. wilsoni has closer relationship with Chionodraco species. Our research will provide more molecular biology information about C. wilsoni and deepen the understanding of Antarctic fishes. [ABSTRACT FROM AUTHOR]

In this study, the complete mitochondrial genome ofStolephorus commersoniiis determined. It is 16,734 bp in length and consists of 13 protein-coding genes, 22 transfer RNA (tRNA) genes, two ribosomal RNA (rRNA) genes, and a control region. Phylogenetic tree was constructed based on the complete mitogenome ofS. commersoniiand closely related 17 other species to assess its phylogenic relationship and evolution. The findings of the study will contribute to the phylogenetic classification and the genetic conservation management ofS. commersonii. [ABSTRACT FROM PUBLISHER]

In this study, we firstly obtained the complete mitochondrial genome DNA sequence of theAmbassisgymnocephalus. Its length is 17,388 bp, containing 13 protein-coding genes, 2 rRNAs, 22 tRNAs and a large noncoding region. The overall length of protein coding genes is 11,448 bp, including A (26.75%), G (15.20%), T (26.44%) and C (31.61%). The A + T content of control region (1555 bp) is 60.45%. The protein-coding gene COI is started by GTG and ended by AGA. From the phylogenetic tree, we findA. gymnocephalusandOreochromis niloticushas the closest relationship among 21 related species. This work will provide some valuable information for further studies onA. gymnocephalusand the family Ambassidae. [ABSTRACT FROM PUBLISHER]

We sequenced a diabeticRattus norvegicusWistar strain mitochondrial genome for the first time (GenBank Accession No. KM114608). Its mitogenome was 16,311 bp and coding 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes. This mitogenome sequence will provide definite genetic information for diabetes disease. [ABSTRACT FROM PUBLISHER]

In the present work we undertook the complete mitochondrial genome sequencing of an important insulin resistance model inbred rat strain for the first time. The total length of the mitogenome was 16,308 bp. It harbored 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and 1 non-coding control region (D-loop region). The mutation events were also reported. [ABSTRACT FROM PUBLISHER]