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Context. Understanding the mechanisms that launch and shape powerful relativistic jets from supermassive black holes (SMBHs) in high-redshift active galactic nuclei (AGNs) is crucial for probing the co-evolution of SMBHs and galaxies over cosmic time. Aims. We focus on the high-redshift (z = 3.396) blazar OH 471 to explore the jet launching mechanism in the early Universe. Methods. Using multi-frequency radio monitoring observations and high-resolution Very Long Baseline Interferometry (VLBI) imaging over three decades, we studied the milliarcsecond structure and long-term variability of OH 471. Results. Our spectral modeling of the radio flux densities revealed a synchrotron self-absorbed spectrum, indicating strong magnetic fields within the compact core. By applying the flux freezing approximation, we estimated the magnetic flux carried by the jet. We found that it reaches or exceeds theoretical predictions for jets powered by black hole spin energy via the Blandford-Znajek mechanism. This implies that OH 471 is in a magnetically arrested disk (MAD) state, where the magnetic flux accumulated near the horizon regulates the accretion flow, allowing for an efficient extraction of black hole rotational energy. Conclusions. Our study demonstrates the dominance of MAD accretion in powering the prominent radio flares and relativistic jets observed in the radio-loud AGN named OH 471. Statistical studies of larger samples of high-redshift AGNs will shed light on the role of MAD accretion in launching and accelerating the earliest relativistic jets. [ABSTRACT FROM AUTHOR]

Background Idiopathic pulmonary fibrosis (IPF) is increasingly recognized as a chronic, progressive and fatal lung disease with an unknown etiology. Current studies focus on revealing the genetic factors in the risk of IPF, making the integrative analysis of genetic variations and transcriptomic alterations of substantial value. Aim This study aimed to improve the understanding of the molecular basis of IPF through an integrative analysis of whole-exome sequencing (WES), bulk RNA sequencing (RNA-seq) and single-cell RNA sequencing (scRNA-seq) data. Methods WES is a powerful tool for studying the genetic basis of IPF, allowing for the identification of genetic variants that may be associated with the development of the disease. RNA-seq data provide a comprehensive view of the transcriptional changes in IPF patients, while scRNA-seq data offer a more granule view of cell-type-specific alterations. Results In this study, we identified a comprehensive mutational landscape of recurrent genomic and transcriptomic variations, including single-nucleotide polymorphisms, CNVs and differentially expressed genes, in IPF populations, which may play a significant role in the development and progression of IPF. Conclusions Our study provided valuable insights into the genetic and transcriptomic variations associated with IPF, revealing changes in gene expression that may contribute to disease development and progression. These findings highlight the importance of an integrative approach to understanding the molecular mechanisms underlying IPF and may pave the way for identifying potential therapeutic targets. [ABSTRACT FROM AUTHOR]

LF refining slag addition is an important factor affecting the end steel composition of the refining process. In order to better control the end steel composition and improve the production efficiency, this paper uses an improved whale optimization algorithm to optimize twin support vector machines to establish a LF refining slag addition prediction model. The LWOA-TSVR model is trained and tested by historical data, and the model has a strong generalization capability and high accuracy. Applying the model to the industrial production process, it was verified that the model has high prediction accuracy and can provide guidance for the actual refining production process of LF refining slag addition, which is important for the control of the end steel composition. [ABSTRACT FROM AUTHOR]

In this work we study d -dimensional majorant properties. We prove that a set of frequencies in |$\mathbb{Z}^d$| satisfies the strict majorant property on |$L^p([0,1]^d)$| for all p  > 0 if and only if the set is affinely independent. We further construct three types of violations of the strict majorant property. Any set of at least d  + 2 frequencies in |$\mathbb{Z}^d$| violates the strict majorant property on |$L^p([0,1]^d)$| for an open interval of |$p \not\in 2\mathbb{N}$| of length 2. Any infinite set of frequencies in |$\mathbb{Z}^d$| violates the strict majorant property on |$L^p([0,1]^d)$| for an infinite sequence of open intervals of |$p \not\in 2\mathbb{N}$| of length 2. Finally, given any p  > 0 with |$p \not\in 2\mathbb{N}$|⁠ , we exhibit a set of d  + 2 frequencies on the moment curve in |$\mathbb{R}^d$| that violate the strict majorant property on |$L^p([0,1]^d).$| [ABSTRACT FROM AUTHOR]

Optical Coherence Tomography (OCT) is a non-invasive method which can obtain high-definition images of cross section (B-scan) of the retina. By investigating the thickness of different layers of the retina in OCT images, one can diagnose ocular diseases in an early stage. Different algorithms have been proposed for retinal layer segmentation including machine learning techniques and various advanced CNN architectures, which have been developed recently. In this research, segmentation of OCT images is carried out for 9 boundaries, equivalent to segmenting eight retinal layers. We investigate different U-net like structures which can be combined with VGG and ResNet architectures to train models using labelled examples, and accuracy for the predicted retinal layers would be compared. In reducing the complexity of networks, a method is proposed based on the concept of domain decomposition when training a large volume of data on a cloud platform. [ABSTRACT FROM AUTHOR]

Drawing inspiration from insect flapping wings, a Flapping Wing Rotor (FWR) has been developed for Micro Aerial Vehicle (MAV) applications. The FWR features unique active flapping and passive rotary kinematics of motion to achieve a high lift coefficient and flight efficiency. This study thoroughly investigates the aerodynamic performance and design of a bio-inspired flexible wing for FWR-MAVs, emphasizing its novel backward-curved wingtip and variable spanwise stiffness resembling a dragonfly's wing. The research departs from previous aerodynamic studies of FWR, which focused predominantly on rectangular and rigid wings, and delves into wing flexibility. Employing Computational Fluid Dynamics (CFD), Computational Structural Dynamics (CSD), and experimental measurements, the study demonstrates the aerodynamic benefits of the dragonfly-inspired FWR wingtip shape and its reinforced structure. Fluid-Structure Interaction (FSI) analysis is used to examine the effects of elastic deformation encompassing twist and bending on aerodynamic forces. The results underscore the importance of bending deformation in enhancing lift and power efficiency and propose a method for analysing variable stiffness along the wingspan using a vortex delay mechanism that is induced by delayed flapping motion. By comparing modelled and measured stiffness, the study validates the flexibility of the FWR wing, revealing optimal aerodynamic efficiency is achieved through moderate flexibility and spanwise stiffness variation. The curving leading-edge beam forming the sweep-back wingtip offers a practical approach to obtaining variable stiffness and aerodynamic benefits for FWR-MAVs. Using the same pair of dragonfly-like flexible wings, FWR-MAVs have effectively exhibited VTOL and hovering flight capabilities, spanning from a 25-g single-motor drive model to a 51-g dual-motor drive model. This research provides valuable insights into flexible wing design for FWR-MAVs, leveraging biomimicry to improve flight efficiency. [ABSTRACT FROM AUTHOR]

The immunogenicity of soluble outer membrane protein K (OmpK)‐ small ubiquitin‐like modifier, OmpK inclusion bodies, formalin, and heat‐killed Vibrio parahaemolyticus cells were prepared and studied in a mouse model. The results of whole‐cell ELISA and Western blot (WB) revealed that the serum against soluble OmpK and OmpK inclusion bodies reacted only with homologous V. parahaemolyticus. Furthermore, recombinant OmpK proteins were not recognized by the serum against whole‐cell V. parahaemolyticus antigens. Unexpectedly, the serum against formalin and heat‐killed V. parahaemolyticus reacted broadly with homologous (an immunization strain) and heterologous (non‐immunization strains) V. parahaemolyticus and Vibrio species. The WB results revealed that the serum against the two V. parahaemolyticus whole‐cell antigens primarily reacted with proteins that were approximately 100, 70, 36, 28, and 22 kDa in the cell lysates from different Vibrio strains, rather than the recombinant OmpK. The 70 and 28 kDa proteins exhibited specificity to Vibrio species, while the 22 kDa protein was more specific to V. parahaemolyticus. This study showed the limitation of recombinant OmpK to prepare diagnostic antibodies and revealed several specific Omps of Vibrio sp. and V. parahaemolyticus that were promising in diagnosis and vaccine development. [ABSTRACT FROM AUTHOR]

Asian Citrus Psyllid (ACP), Diaphorina citri, is a key vector transmitting the causative agent of Huanglongbing (HLB) disease. Population growth of ACP is evident after feeding on plant flush shoots, as they only oviposit here. However, the underlying mechanism as to why flush shoots govern oviposition is unclear. This study compares the fecundity and ovarian morphology of ACP between young flush and mature leaves. Furthermore, the transcriptome of mated females infesting Murraya paniculata was analysed. Finally, the gene of the key Target of Rapamycin (TOR) signalling pathway was silenced by RNAi. Results indicated that flush shoot feeding activated the development of the psyllids ovary and therefore induced oviposition. A total of 126 and 2794 differentially expressed genes were detected at 1 and 5 days, respectively, after pest infestation of flush shoots compared to mature leaves. Many genes are involved in protein metabolism, Mitogen‐Activated Protein Kinase (MAPK) signalling pathway, hormone synthesis, and TOR signalling pathway: all thought to activate reproduction. Silencing of the positive regulator gene DcRheb in the TOR pathway resulted in lower levels of ecdysone and juvenile hormone and decreased vitellogenin synthesis, further disrupting reproductive ability. This study enhances understanding of the molecular mechanism underlying ACP's reproductive strategy. [ABSTRACT FROM AUTHOR]

Optical properties and structural variations of Na0.5Bi0.5TiO3-7%BaTiO3 (NBT-7%BT) single crystal have been studied by temperature-dependent optical ellipsometry and Raman spectroscopy from 4.2 to 300 K. The second derivative of the complex dielectric functions reveals two interband transitions (Ecp1 and Ecp2) located at about 3.49 and 4.25 eV, respectively. Depending on the temperature evolution of electronic transitions, structural variations appear near 60, 150, and 240 K, respectively. These anomalies are also well illustrated from the low-frequency phonon modes involving vibrations of Bi. The low-temperature structural variations of NBT-7%BT crystal can be associated with instability of the crystalline lattice driven by off-centered Bi ions, followed by the variations of polarizability of the unit cells. [ABSTRACT FROM AUTHOR]

A 2D fully kinetic particle-in-cell plus Monte Carlo collision model is developed to simulate the plasma characteristics of the ion thruster discharge chamber. The interaction between charged particles and the dynamic electric field, the confinement of the static magnetic field, and the particle collisions are simulated. The self-similar scaling method, the multigrid method, sub-cycle time, and neutral particle pre-distribution techniques work together to perform the full-particle and full-kinetic simulation. The steady-state results such as particle number, current flows, static magnetic field, electric potential, particle density, and energy distributions are obtained and discussed. Moreover, the plasma generation and transport, the dynamic behavior of neutral particles, and the influence of the gas flow rate on the plasma are analyzed. The density distribution of charged particles indicates that the electrons are strongly constrained by the magnetic field, and the magnetization characteristics are distinguished from that of ions. Neutral particles are heavily ionized and are depleted along the central line, which is consistent with the area with a higher ionization rate. At last, it is found that the energy and density of charged particles are sensitive to the change of the gas flow rate. [ABSTRACT FROM AUTHOR]

Based on recent work by Guo et al. ["An efficient lattice Boltzmann method for compressible aerodynamics on D3Q19 lattice," J. Comput. Phys. 418, 109570 (2020)], an improved thermal hybrid recursive regularized lattice Boltzmann model (iHRR-ρ) on a regular lattice is developed for two- and three-dimensional compressible laminar and turbulent flows. To enhance the numerical stability in a broad range of Courant–Friedrichs–Lewy numbers and in under-resolved simulations, a new equilibrium density distribution function is proposed to enlarge its positivity region in the Mach–temperature plane. An embedded hybridizing procedure is introduced in the quasi-symmetry correction terms, which allow for a decoupled treatment of unphysical modes and physical under-resolved turbulent scales on coarse grids. To handle compressible turbulent flows, the under-resolved scales are modeled using the original hybrid recursive regularized collision model given by Jacob et al. ["A new hybrid recursive regularised Bhatnagar–Gross–Krook collision model for Lattice Boltzmann method-based large eddy simulation," J. Turbul. 19, 1051–1076 (2018)] equipped with Vreman's subgrid model for the large-eddy simulation. The validity and accuracy of the present method for laminar and turbulent compressible flows are assessed by considering six test cases: (I) viscous shock wave internal structure, (II) isentropic vortex convection in a supersonic regime, (III) non-isothermal acoustic pulse, (IV) vortex–shock wave interaction, (V) supersonic flow over NACA airfoil at Re = 10 000 and Ma = 1.5, and (VI) compressible Taylor–Green vortex at Ma = 0.29. [ABSTRACT FROM AUTHOR]

Two mononuclear Cu(II) and Co(II) halogen-substituted salamo-based complexes of the formulas [Cu(L)] and [Co(L)(H2O)2] have been synthesized and characterized by elemental analyses, FT-IR and UV-Vis absorption spectra, and X-ray crystallography. The Cu(II) complex has crystallized in the monoclinic system, space group P21/n with Cu(II) atom located in the N2O2 cavity. In the Co(II) complex, the center Co(II) atom has exhibited a slightly distorted octahedral geometry with halogen-substituted salamo-based bisoxime forming the basal N2O2 coordination plane and two oxygen atoms of two coordinated water molecules in the axial positions. Non-covalent interactions like hydrogen bonding and π···π stacking interactions are operative in construction of supramolecular architectures. The crystal structures and supramolecular features of the complexes have been discussed in details. Hirshfeld surfaces analyses has indicated stability of both complexes. The Cu(II) complex has demonstrated excellent bio-inspired catalytic properties towards oxidative coupling of 2-AP in MeCN medium. Fluorescence properties of H2L and its Cu(II) and Co(II) complexes have also been discussed. [ABSTRACT FROM AUTHOR]

To research the influence of powder feed rate on the outflow field of a high power diode laser (HPDL) coaxial powder feeding nozzle, FLUENT software was adopted to simulate the outflow field of powder flow under different powder feeding rates. Results show that the higher the powder feeding rate was, the higher powder flow velocity and concentration were at the convergence point, but the focal length was maintained at 0.015 m. When the powder feeding rate was 15 g/min, the powder had a good aggregation property. When the rate of powder feeding exceeded 15 g/min, the spot diameter increased. The experiment of powder convergence and laser cladding forming was carried out by using four-channel coaxial powder feeding nozzles. It was found that the best forming effect is achieved when the powder feeding rate was 15 g/min, which was consistent with simulation results and had a high reference significance for optimization of process parameters of the coaxial nozzle. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the proportion of non‐ambulatory dogs with cervical intervertebral disc herniation (IVDH) in a private clinic and to compare signalment and outcome between those that underwent single or multiple ventral slot decompression (VSD). Design: Retrospective cohort study. Methods: After screening 43,378 medical records (January 2010–September 2016), those of 185 dogs with non‐ambulatory tetraparesis or tetraplegia along with cervical IVDH that had undergone single (123) or multiple (62) VSD were included in this study. Data on signalment, preoperative neurological status, location of affected intervertebral disc(s), time to ambulation and short‐term outcome were compared between single and multiple VSD groups. Results: The proportion of non‐ambulatory dogs with IVDH was 35.3%. The prevalence of non‐ambulation was higher in male dogs (0.56%) than in female dogs (0.26%; P < 0.001) and in neutered dogs than in unneutered dogs (0.51% and 0.27%, respectively, P < 0.001). After surgery, 96.2% of the dogs reached ambulatory status. Dogs with multiple IVDH were older than those with single IVDH. Sex, neutering status or size did not affect the outcome or ambulation status postsurgery. The Pekingese was the most commonly affected breed in both groups. There was no difference in the time to reach ambulation and the presence of neurological deficits after surgery between dogs that underwent single and multiple VSD. Conclusions: In this cohort, dogs undergoing multiple VSD had a good postoperative outcome, and their short‐term functional recovery was equal to that of dogs undergoing single ventral slot compression. [ABSTRACT FROM AUTHOR]

The stigma of Crocus sativus is used in traditional Chinese medicine and has drawn attention as a rich source of crocin, a compound with a reported activity that counters various cancers, depression, and cardiovascular diseases. However, our knowledge of crocin biosynthesis in Crocus is still limited. To identify the genes that encode key enzymes responsible for crocin production, transcriptome analyses of Crocus stigma, petal, and stamen were performed. There were 109 136 unigenes in the three Crocus flower tissues: 10 862 unigenes were expressed explicitly in stigmas. A total of 469 and 335 down-regulated differentially expressed genes in comparison to stigmas were detected in stamens and petals, respectively. There were 290 down-regulated genes in both tissues. The gene ontology enrichment and Kyoto Encyclopedia of Genes and Genomes analysis revealed that most genes in the two tissues served a similar function. The results of the differences of gene expression among the three tissues showed that most of the carotenoid pathway genes in stigmas had a high expression which was a benefit for producing zeaxanthin, a substrate of crocin. Fourteen candidate genes were identified in Crocus from the co-down-regulated genes, and the genes were expressed explicitly in stigmas and were predicted to be involved in crocin biosynthesis. Overall, the expressions of genes in the crocin biosynthesis pathway in the three Crocus flower tissues had a positive relationship with their crocin content, and some new candidate genes related to crocin biosynthesis were identified. The results can help elucidate the crocin biosynthesis pathway in Crocus. [ABSTRACT FROM AUTHOR]

To reveal the enhancing energy coupling effect of plasma, a comparison of the welding mode transformation process during 1-µm and 10-µm laser welding of aluminum alloys is carried out through experimental observation and theoretical analysis. The heat conduction welding stage hardly exists in 10-µm laser welding and obviously exists in 1-µm laser welding. Alloy composition and surface roughness of the welded plate hardly influence the deep penetration welding threshold (DPWT) of the 10-µm laser, whereas they have a significant impact on that of the 1-µm laser. In addition, 1-µm laser welding and 10-µm laser welding have similar DPWTs. These phenomena are attributed to the formation of plasma near the workpiece surface during 10-µm laser welding owing to metal vapor breakdown by 10-µm laser irradiation. The plasma remarkably enhances the energy coupling between the 10-µm laser and workpiece by thermal conduction, and the DPWT of the 10-µm laser is thus reduced to approximately equal to that of the 1-µm laser. [ABSTRACT FROM AUTHOR]

Complex geometries and open boundaries have been intensively studied in the nearly incompressible lattice Boltzmann method (LBM) framework. Therefore, only few boundary conditions for the high speed fully compressible LBM have been proposed. This paper deals with the definition of efficient boundary conditions for the compressible LBM methods, with the emphasis put on the newly proposed hybrid recursive regularized D3Q19 LBM (HRR-LBM) with applications to compressible aerodynamics. The straightforward simple extrapolation-based far-field boundary conditions, the characteristic boundary conditions, and the absorbing sponge layer approach are extended and estimated in the HRR-LBM for the choice of open boundaries. Moreover, a cut-cell type approach to handle the immersed solid is proposed to model both slip and no-slip wall boundary conditions with either isothermal or adiabatic behavior. The proposed implementations are assessed considering the simulation of (i) isentropic vortex convection with subsonic to supersonic inflow and outflow conditions, (ii) two-dimensional (2D) compressible mixing layer, (iii) steady inviscid transonic flow over a National Advisory Committee for Aeronautics (NACA) 0012 airfoil, (iv) unsteady viscous transonic flow over a NACA 0012 airfoil, and (v) three-dimensional (3D) transonic flows over a German Aerospace Center (DLR) F6 full aircraft configuration. [ABSTRACT FROM AUTHOR]

Two spring wheat varieties were used to study alleviating effects of exogenous spermine (Spm) and spermidine (Spd) on agronomic traits and photosynthesis under high temperature treatment (HT). Our results showed that HT significantly decreased grain mass per panicle of heat-resistant variety (XC 6) by 25% and heat-sensitive variety (XC 31) by 32%. After HT, i.e., at 13 d after flowering, the decrease in net photosynthetic rate of XC 6 (38%) was lower than that of XC 31 (53%); the reason for this was related to XC 6, which could maintain correspondingly normal chlorophyll content (Chl), stomatal conductance (gs), transpiration rate (E), and intercellular CO2 concentration. Exogenous Spm and Spd could increase relative water content, Chl, gs, E, the maximal quantum yield of PSII photochemistry, effective quantum yield of PSII photochemistry, antenna conversion efficiency, and photochemical quenching coefficient of flag leaves under HT. Our results indicated that the heat resistance of XC 6 is better than that of XC 31 and exogenous Spm and Spd could alleviate the heat injury of photosynthesis of wheat flag leaves. [ABSTRACT FROM AUTHOR]

Objective: Paraquat (PQ) poisoning is a significant cause of mortality and morbidity in developing countries. Poor prognostic outcomes have been attributed to the herbicide's toxicity and the lack of effective treatments. Our study aims to investigate the changes in lymphocyte count in both patients who survived and died from PQ poisoning and explore the prognostic value. Method: This is a retrospective case serials observational study. Adult patients admitted with acute PQ poisoning. The notes of 1000 patients who presented with acute PQ poisoning were reviewed. One hundred thirty patients having the T lymphocyte met the inclusion criteria and were grouped into those that survived the poisoning (95) and non-survivors (35). Results: On admission, non-survivors had a higher ingestion volume of PQ and urine PQ concentration as well as higher severity indices (Acute Physiology and Chronic Health Evaluation 2, Sequential Organ Failure Assessment, and Poisoning Severity Score). Patients in the survival group had a higher dosage of immunosuppressant and a longer hospital stay. Leukocytes, especially neutrophils, were higher among non-survivors; however, the converse was found with lymphocytes. T lymphocyte (CD3) count was consistently higher among survivors as well as the subgroups CD4+ and CD8+. No differences in the ratio of CD4/CD8 were found between the groups. Conclusion: Our study has shown that changes in lymphocyte count as its subgroups could indicate a host's immune status and lymphocytes play an important role as a surrogate marker of host immunity, which could be a useful prognostic tool in the assessment of this disease. [ABSTRACT FROM AUTHOR]

Bulk acoustic wave induced mixing in microfluidic systems has been studied by using a pair of small size ultrasonic transducers integrated into a prototype polydimethylsiloxane device. The acoustic properties of the integrated ultrasonic transducers were evaluated, demonstrating the generation of bulk acoustic wave in the mixing chamber when a low ac voltage is applied. Then, the mixing efficiency of the device was studied by using two stream laminar flows and taking into account the particular geometry of the mixing chamber. Because of the limited power consumption, the system should be compatible with the requirements of a number of applications in both analytical chemistry and biology. [ABSTRACT FROM AUTHOR]

Ti alloy clad plate is of great interest for marine and petrochemical industry applications. However, high interfacial bonding is hardly obtained in the Ti alloy clad plate due to the brittle intermetallic compounds (IMCs) forming at the interface. In this study, a Ti-6Al-4V alloy/EH690 steel clad plate was fabricated by vacuum rolling and subsequently tempered to control the mechanical property of the steel substrate. The tempered sorbite appeared in the EH690 steel after quenching and tempering (QT). A decarburized zone, Fe 2 Ti + TiC mixed phases layer, and β-Ti layer were formed at the interface between steel and Ti. The brittle IMCs with high lattice mismatch resulted in a low interfacial strength of 108 MPa. To improve bonding strength, Nb was inserted between Ti and steel as an interlayer, which effectively inhibited the inter-diffusion of Ti, Fe, and C without brittle TiC or Fe-Ti IMCs. A (Ti, Nb) solid solution layer with high plasticity was present at the Nb/Ti interface. Fe 2 Nb and Fe 7 Nb 6 phases were detected at the steel/Nb interface, exhibiting less brittleness and hardness compared to Fe-Ti IMCs. The interfacial shear strength was up to 265 MPa after adding the Nb interlayer, showing a mixed fracture mode of brittleness and ductility. [ABSTRACT FROM AUTHOR]

Ti/Al clad plate is a highly promising material due to its low cost, lightweight nature, high strength, and excellent corrosion resistance. However, the deformation coordination between Ti and Al is very poor, and both metals easily are oxidated, resulting in a weak interfacial bonding. In this study, Ti/Al clad plate was fabricated by vacuum rolling, obtaining a clear interface without oxidation and compound. The as-rolled Ti/Al clad plate had a shear strength of 76 MPa with the fracture being at the Al substrate due to the solution of Mg 2 Si precipitates in the Al substrate during rolling. As a result, the solution and aging is necessary to enhance interfacial bonding. There were fine and dispersed Mg 2 Si precipitates in the as-treated Al substrate, and an (Al, Si) 3 Ti layer with ∼300 nm thickness appeared at the interface. Besides, the interfacial shear strength was up to 140 MPa, and the fracture still was at the Al side. The as-treated clad plate had an elongation of 33.5% which exceeded that of 25.8% calculated by the mixed rule. Obviously, the thin (Al, Si) 3 Ti layer is helpful to improve interfacial shear strength and plasticity of the Ti/Al clad plate. [ABSTRACT FROM AUTHOR]

We report the optical properties of BeCdSe/ZnCdMgSe single quantum well (QW) structures that consist of closely lattice matched ZnCdMgSe barrier layers and a strained BeCdSe QW layer (Δa/a=1.95%) grown on InP substrates. Emission from the red to the green regions of the visible spectrum was obtained from the structures with the QW thickness varying from 95 to 12 Å. Efficient QW emission, dominated by an exciton recombination behavior, was observed. From the Arrhenius plot of the integrated emission intensity as a function of temperature, an activation energy of 61 meV was obtained for a BeCdSe QW structure with a 48 Å thick QW layer. Parameters that describe the temperature dependence of the near band edge emission energy and the broadening of the excitonic emission were evaluated. Our results indicate that the BeCdSe-based QW structures are attractive for application as red light emitters. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

High crystalline quality ZnBeSe epilayers were grown nearly lattice matched to GaAs (001) substrates by molecular beam epitaxy with a Be-Zn co-irradiation. A (12) reflection high energy electron diffraction pattern was observed after the Be-Zn co-irradiation of the GaAs (24) surface. A high p-type doping level of 1.510cm was achieved for (N+Te) triple-delta doping ( doping) of ZnBeSe epilayers, whereby three adjacent layers of N and Te were deposited in each doping cycle. X-ray diffraction measurements reveal that (N+Te) -doped ZnBeSe samples with a Te concentration of about 0.5% remain of very high crystalline quality with an X-ray rocking curve linewidth of 51 arcsec. Low temperature photoluminescence measurements show some emission peaks related to Te clusters and/or Ten≥3 clusters. c 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Distributed Bragg reflectors (DBRs) based on ZnCdSe and ZnCdMgSe quarter wave layers have been grown on InP (001) substrates by molecular beam epitaxy. Their reflectivity maxima were controlled by the individual thicknesses of constituent layers, and were adjusted in the range of 615-500 nm, covering the red, green, and blue-green regions of the visible spectrum. The crystal quality of the structures was assessed by double crystal x-ray diffraction measurements. Reflectivity as high as 95% was achieved for the DBR structures that consisted of 16 periods. Theoretical calculations, based on the transfer matrix method, predict that a reflectivity above 99% can be achieved by increasing the number of periods to between 20 and 26. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The hydraulic column is the key component of the hydraulic support in the mining environment. To improve a hydraulic column's reliability and service life, the Fe-based laser clad layer was prepared on 27SiMn steel substrate using a high power diode laser (HPDL). The results show that the best process parameters are the laser power of 3000 W, the scanning speed of 5 mm/s, the feeding fraction of 16 g/min and the lapping rate of 50%. The macroscopic morphology of the laser clad layer has no cracks, pits and other defects. The laser clad layer has a fine and uniform microstructure and can form a metallurgical bonding with the 27SiMn steel substrate. Elements distribution is uniform and it appears fluctuation around the melting line. The cladding hardness is 1.3 times higher than the substrate and the wear resistance is 7.7 times higher than the substrate. The self-corrosion potential of the laser clad layer is significantly shifted positively and has a significant passivation region. After 96 hours of salt pray corrosion test, the surface of the laser clad layer is still smooth. The laser clad layer has better corrosion resistance and performance than the substrate, which can meet the requirements of hydraulic support in the mining environment. [ABSTRACT FROM AUTHOR]

The hydraulic column is the key component of the hydraulic support in the mining environment. To improve a hydraulic column’s reliability and service life, the Fe-based laser clad layer was prepared on 27SiMn steel substrate using a high power diode laser (HPDL). The results show that the best process parameters are the laser power of 3000 W, the scanning speed of 5 mm/s, the feeding fraction of 16 g/min and the lapping rate of 50%. The macroscopic morphology of the laser clad layer has no cracks, pits and other defects. The laser clad layer has a fine and uniform microstructure and can form a metallurgical bonding with the 27SiMn steel substrate. Elements distribution is uniform and it appears fluctuation around the melting line. The cladding hardness is 1.3 times higher than the substrate and the wear resistance is 7.7 times higher than the substrate. The self-corrosion potential of the laser clad layer is significantly shifted positively and has a significant passivation region. After 96 hours of salt pray corrosion test, the surface of the laser clad layer is still smooth. The laser clad layer has better corrosion resistance and performance than the substrate, which can meet the requirements of hydraulic support in the mining environment. [ABSTRACT FROM AUTHOR]

This article discusses a study that identified two novel mutations in the TTC37 gene in two Chinese patients with Crohn's disease (CD). These mutations are the first two Asian cases of CD associated with TTC37 mutations. The TTC37 gene is involved in RNA exosome regulation and mutations in this gene have been linked to trichohepatoenteric syndrome and IBD. The study suggests that TTC37 mutations may influence the progression of CD by altering mitochondrial structure and function. Further research is needed to understand the precise mechanisms involved. [Extracted from the article]

In this paper, a two-dimensional axisymmetric particle-in-cell plus Monte Carlo collision numerical model is developed to simulate the plasma and electromagnetic characteristics inside the discharge chamber of an ion thruster. This model tracks three major particle types: primary electrons, secondary electrons, and xenon ions. The neutral particles are treated as a background gas, and the collision mechanism between electrons and neutral gas is modeled in detail. Besides the external electric field and magnetic field, the time-varying electromagnetic fields caused by the movement of the charged particles are considered. Compared to the electrostatic model, the electromagnetic model can further study the electromagnetic radiation characteristics of the discharge chamber. The numerical results are presented and discussed, including the particle number density distributions, the particle energy distributions, and the time-varying electromagnetic fields. At last, the influence of the electromagnetic effect on ion dynamics is analyzed. [ABSTRACT FROM AUTHOR]

Background Cervical cancer is the 2nd most common malignant tumour in women worldwide. Previous research studies have given little attention to its prognostic factors in the rapidly growing Asian American population. In the present study, we explored prognostic factors in Asian and white American patients with cervical cancer, considering competing risks. Methods The study included 58,780 patients with cervical cancer, of whom 54,827 were white and 3953 were Asian American, and for all of whom complete clinical information was available in the U.S. Surveillance, Epidemiology, and End Results database. Death from cervical cancer was considered to be the event of interest, and deaths from other causes were defined as competing risks. The cumulative incidence function and the Fine-Gray method were applied for univariate and multivariate analysis respectively. Results We found that, for all patients (white and Asian American combined), the cumulative incidence function was associated with several factors, such as age at diagnosis, figo (Fédération internationale de Gynécologie et d'Obstétrique) stage, registry area, and lymph node metastasis. Similar results were found when considering white patients only. However, for Asian American patients, registry area was not associated with the cumulative incidence function, but the other factors (for example, figo stage) remained statistically significant. Similarly, in multivariate analyses, we found that age at diagnosis, figo stage, lymph node metastasis, tumour histology, treatment method, and race were all associated with prognosis. Conclusions Survival status differs for white and Asian American patients with cervical cancer. Our results could guide the treatment of, and facilitate prognostic judgments about, white and Asian American patients with cervical cancer. [ABSTRACT FROM AUTHOR]

Highlights • Combined flow and heat transfer measurements were performed for a perturbed backward facing step flow. • The convective heat transfer rate was found to be closely associated with the turbulent kinetic energy and the streamline curvature. • A critical perturbation frequency of fH / U o = 0.22 was identified from measurement results. • The impact of the perturbation amplitude on the turbulence quantities and heat transfer was large for a subcritical perturbation frequency, but relatively smaller for a supercritical one. Abstract The flow fields and convective heat transfer downstream of a backward facing step (BFS) with a Re H = 9630 were investigated using experimental methods. The BFS flow was perturbed using a synthetic jet actuator deployed at the separation point with a range of perturbation frequencies ( f A H / U o = 0.04 - 0.39) and amplitudes ( u A ′ / U o = 0.3 - 0.9). The momentum transport across the shear layer appeared to be enhanced by the perturbations, resulting in a shortened recirculation bubble, a larger curvature in the time-average streamline over the separation bubble and enhanced heat transfer rate in the attachment and recirculation regions. The distributions of the reattachment length, streamline curvature, static base pressure, turbulent kinetic energy and convective heat transfer rate all suggested there was a critical perturbation frequency f A H / U o ≈ 0.22 where the perturbation frequency matched the characteristic frequency of the attaching shear layer. Flow changed only slightly with the perturbation amplitude when f A H / U o ≳ 0.22 but changed significantly when f A H / U o ≲ 0.22. [ABSTRACT FROM AUTHOR]

During insect larval–pupal metamorphosis, the obsolete larval organs and tissues undergo histolysis and programmed cell death to recycle cellular materials. It has been demonstrated that some cathepsins are essential for histolysis in larval tissues, but the process of tissue destruction is not well documented. Fat body, the homologous organ to mammalian liver and adipose tissue, goes through a distinct destruction process during larval–pupal transition. Herein, we found that most of the Bombyx proteases – including Bombyx cathepsin B (BmCatB) (BmCatLL-2), Bombyx cathepsin D (BmCatD), Bombyx cathepsin L like‐1 (BmCatLL-1) and –2(BmCatLL-2), Bombyx fibroinase (BmBcp), Bombyx matrix metalloprotease (BmMmp), Bombyx A disintegrin and metalloproteinase with thrombospondin motifs 1 (BmAdamTS‐1), Bombyx A disintegrin and metalloproteinase with thrombospondin motifs like (BmAdamTS L) and Bombyx cysteine protease inhibitor (Bmbcpi)– were expressed highly in fat body during feeding and metamorphosis, with a peak occurring during the nonfeeding moulting or prepupal stage, as well as being responsive to 20‐hydroxyecdysone (20E). The aforementioned protease genes expression was upregulated by injection of 20E into the feeding larvae, while blocking 20E signalling transduction led to downregulation. Western blotting and immunofluorescent staining of BmCatB and BmBcp confirmed the coincident variation of their messenger RNA (mRNA) and protein level during the development and after the treatments. Moreover, BmCatB, BmBcp, BmMmp and BmAdamTS‐1 RNA interference all led to blockage of larval fat body destruction. Taken together, we conclude that 20E regulates larval fat body destruction by upregulating related protease gene expression and protein levels during larval–pupal transition. [ABSTRACT FROM AUTHOR]

It has been known that the internal structure of metallic glass is composed of elastic region and fragile region. However, it is not clear whether the distribution of these regions has an effect on the occurrence of crystallization behavior. Here, the molecular dynamics simulation is employed to investigate the nanometer scale crystallization behavior in metallic glass. A regional selective characteristic is revealed for the occurrence of crystallization behavior in the metallic glasses, which is different from that in the melt, showing the unique nature of crystallization behavior in amorphous system. It is observed that the crystallization behavior occurs first in the elastic region dominated by the icosahedral network, rather than in the fragile region dominated by the low-population polyhedron. This phenomenon can be attributed to that the Gibbs free energy barrier between the BCC structure and the low-population polyhedron in the fragile region is higher than the free energy barrier between the BCC structure and the icosahedral network. [ABSTRACT FROM AUTHOR]

Abstract Background Risk factors for venous thromboembolism (VTE) in women with breast cancer are not known by race. Objectives The purpose of our study was to determine risk factors for VTE and VTE associated mortality in white and black women with breast cancer. Patients and methods The SEER-Medicare merged database (2000 to 2011) was used for women 65 years and older diagnosed with breast cancer. Stratified by race, logistic regression was used to examine risk factors for VTE and Cox proportional hazards regression was used to evaluate the effect of VTE on mortality. Results There were 276,028 women 65 years and older with breast cancer. Of those, 6.4% white and 10.1% black women with breast cancer had a diagnosis of VTE. In adjusted analyses by race, risk of VTE increased with each year of age in both white and black cohorts. VTE was independently associated with distant metastasis and coexisting medical conditions in white women and in black women, hypertension, heart failure and hyperlipidemia were determinants of VTE. VTE was not associated with distant metastasis in black women. Tumor size, grade, and receptor status were also not independently associated with VTE risk in either white or black women. VTE accorded a higher risk of death in both white (HR = 1.49, 95% CI, 1.34–1.65) and black women (HR = 1.57, 95% CI, 1.23–2.00) with breast cancer. Conclusion The study identified VTE risk factors and effect of VTE on mortality in white and black older women with breast cancer. Highlights • Higher risk of VTE in black women than white women with breast cancer • Risk factors in white women: distant metastasis and coexisting medical conditions • Risk factors in black women: hypertension, heart failure and hyperlipidemia • VTE associated mortality was higher in black women than white women. • VTE was an independent risk factor for mortality in both white and black women. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the properties of the borate bonding agents (BBAS) including chemical durability, biocompatibility and bonding characteristics of porcelain to Ti6Al4V. The bond strength was performed by the three-point bending test. And the chemical durability and ion release of BBAS were tested by chemical soaking and inductively coupled plasma optical emission spectrometry (ICP-OES), respectively. Moreover, cytotoxicity was evaluated by cell viability assay and cell adhesion using human osteosarcoma cells (MG-63) and cell counter kit-8 (CCK-8) assay. To investigate the influences of composition and microstructure changes on all the properties mentioned above, the 11 B and 27 Al spectra and infrared spectra of BBAS were measured by solid-state nuclear magnetic resonance (SSNMR) and Fourier transform infrared spectroscopy (FTIR), respectively. Combined with all these properties of BBAS, the optimal addition proportion of Al 2 O 3 into BBAS is 20 mol%. The relative contents of [BO3], [BO4], [AlO4], [AlO5] and [AlO6] have great influences on these properties of BBAS. BBAS, possessing excellent chemical durability, good biocompatibility and low ion release and being an effective way to improve the Ti6Al4V-porcelain bond strength, have significant clinical potentials in porcelain fused to metal restorations. [ABSTRACT FROM AUTHOR]

Inspired by insect flapping wings, a novel flapping wing rotor (FWR) has been developed for micro aerial vehicle (MAV) application. The FWR combines flapping with rotary kinematics of motions to achieve high agility and efficiency of flight. To demonstrate the feasibility of FWR flight and its potential MAV application, an extensive and comprehensive study has been performed. The study includes design, analysis, manufacture, experimental and flight test of a flyable micro FWR model of only 2.6 g weight. By experiment, the FWR kinematic motion and aerodynamic lift were measured using high speed camera and load cells. Within a range of input power, the difference between the measured aerodynamic force and the analytical results by a quasi-steady model was found to be within 3.1%–15.7%. It is noted that the FWR aeroelastic effect plays a significant role to obtain an ideal large angle of attack especially in up-stroke and enhance the FWR performance. Further analysis of the unsteady aerodynamic characteristics has been carried out based on the detailed airflow field of the FWR in a flapping cycle by CFD method. A successful vertical take-off and short hovering flight of the micro FWR model has been achieved for the first time in the research field. The flight test demonstrates the FWR feasibility and its unique feature of flight dynamics and stability for the first time. These characteristics have also been simulated by using ADAMS software interfaced with the aerodynamic model. [ABSTRACT FROM AUTHOR]

Discusses a spectroscopic ellipsometry study of cerium dioxide thin films grown on sapphire by radio frequency magnetron sputtering. Examination of the crystallinity, chemical structure and surface morphology of the films through x-ray diffraction, x-ray photoelectron spectroscopy and atomic force microscopy; Analysis of the surface roughness of the crystalline films; Experimental details and result of the study.

Unconventional exchange bias (EB) has been studied in CoCr2O4/Cr2O3 nanocomposites, in which the Curie temperature of the ferrimagnetic CoCr2O4 is much lower than the Néel temperature of the antiferromagnetic Cr2O3. A negative EB field of about 2.5 kOe at 5 K is achieved upon cooling in a field of 30 kOe. Meanwhile, the coercivity of the CoCr2O4 nanoparticles has been enhanced significantly by coupling with Cr2O3. The effect of the cooling field on the EB field and coercivity at 10 K has also been investigated. The domain-state model is used to interpret the unconventional EB. Cooling field may play a decisive role in the creation of the interfacial spin configuration for the unconventional EB, not only by exchange interaction between the induced magnetization of a polarized paramagnet and interfacial spins of an antiferromagnet but also by Zeeman interaction between the domain-state surplus magnetization and the external field. [ABSTRACT FROM AUTHOR]

Effects of the distribution of rare-earth elements on 2:14:1-type Ce-based sintered magnet with same nominal composition were investigated by respectively doping Nd-Fe and Ce-Fe eutectic alloys. The coercivity and the thermal stability of the magnet doping Nd-Fe alloy revealed more excellent performance ( i H c  = 12.19kOe,α = −0.1474%/°C, β = −0.5129%/°C) than those of the magnet doping Ce-Fe alloy ( i H c  = 10.13kOe, α = −0.1665%/°C, β = −0.5271%/°C). The difference of the newly formed grain boundary phases and elemental enrichment variation of the matrix phase grain for the processed magnets were two major reasons of the coercivity discrepancy. Ce-based magnet with optimized structure was obtained and this method was promising to maximize the utilization of abundant rare-earth element Ce in 2:14:1-type magnet. [ABSTRACT FROM AUTHOR]

We have investigated the magnetism of CoCrFeNiZr x (x = 0.4–0.5) eutectic high-entropy alloys (HEAs) in relation to their microstructure by XRD, SEM, magnetization, specific heat and electrical resistivity measurements. Two structural phases develop in the CoCrFeNiZr x HEAs, a Zr-free fcc solid solution and a Zr-containing C15 Laves-phase intermetallic compound, where in both phases magnetic transition elements Co, Cr, Fe and Ni substitute each other in a random-like manner. Relative fractions of the two phases change substantially with the Zr concentration. Microstructurally, the two phases form alternatively grown fine lamellar structure typical of eutectic alloys. In addition, bulky dendrites of the fcc solid solution form in large number for the x = 0.40 concentration and in small number for x = 0.45. Two magnetic structures coexist in the CoCrFeNiZr x HEAs. The first is a disordered ferromagnetic (FM) phase that develops in the interior of large dendrites of the fcc solid solution and in some larger lamellas of this phase. The second phase is superparamagnetic-like and originates from the remaining spins of the fcc solid solution fraction, located at the surfaces and in the interfaces, and from all spins of the C15 Laves-phase fraction. The relative magnitude of the disordered FM-state magnetization with respect to the superparamagnetic magnetization in the samples with different Zr concentration is predominantly determined by the volume fraction of the fcc bulky dendrites. There is no one-to-one relation between the two magnetic structures on one side and the two structural components of the CoCrFeNiZr x eutectic mixtures on the other side. The magnetism of multi-phase HEAs containing magnetic elements cannot be described as a compositional average of magnetic properties of the constituent phases. [ABSTRACT FROM AUTHOR]

Brassinolide (BL) alleviates salt injury in cotton seedlings; however, little is known about the molecular mechanisms of this response. In this study, digital gene expression analysis was performed to better understand the regulatory pathways of BL in NaCl-stressed cotton ( Gossypium hirsutum L.). Compared with control plants (CK), a total of 1 162 and 7 659 differentially expressed genes (DEGs) were detected in the leaves and roots of NaCl-treated plants, respectively. Most of the DEGs in NaCl-treated plants, compared to CK, were regulated by BL. Moreover, expression patterns of DEGs in BL+NaCl treated plants were similar to those in CK plants; however, the responses of DEGs in the leaves and roots of NaCl-treated plants to BL differed. In the roots, BL-regulated DEGs were involved in protein biosynthesis, whereas in the leaves, BL promoted photosynthesis in NaCl-stressed cotton. BL treatment also significantly increased the overall biomass, chlorophyll a + b content in leaves, and the protein content in roots in NaCl-stressed cotton. The downregulation of stress-responsive genes in BL+NaCl-stressed leaves was also found. These results suggest that BL can alleviate NaCl injury in cotton plants. [ABSTRACT FROM AUTHOR]

The effectiveness of a passive gust alleviation device (PGAD) mounted at the wingtip of aircraft in conventional and flying-wing configurations have been studied in previous research. However the PGAD influence on the aeroelastic stability in particular the body freedom flutter (BFF) of a flying-wing aircraft remains as a concern. This present investigation is focused on evaluating the beneficial effect of PGAD on both gust load alleviation and BFF of a small flying-wing aircraft of high aspect ratio wing made of composite. A small range of (1-cos) type of gust load has been considered to select a representative critical gust load case for the study. A parametric study indicates that there is a narrow band of optimal key parameters for the PGAD design. Subsequently a set of optimal parameters is selected to further the analysis of the PGAD mechanism. The case study results show that the PGAD can make the bending moment at the wing root due to gust reduced by 16%. In addition, the BFF speed of the flying-wing aircraft is increased by 4.2%. The investigation reveals that the PGAD mode and its interaction with the wing bending mode and short period oscillation of the aircraft can have beneficial aeroelastic effect on both gust alleviation and flutter suppression. [ABSTRACT FROM AUTHOR]

Mandibular functions are associated with electromyographic activity of the jaw muscles and also the sternocleidomastoid muscle ( SCM). The precise spatiotemporal relation of SCM and masticatory muscles activities during chewing is worthy of investigation. To analyse the sequential recruitment of SCM and masseter activities during chewing as indicated by the spatiotemporal locations of their activity peaks. Jaw movements and bilateral surface electromyographic activity of SCM and masseter were recorded during gum chewing in 20 healthy subjects. The timing order was decided by comparing the length of time from the time when the opening started to the time when the surface electromyographic activity reached its peak value. Spatial order was analysed by locating the peak electromyographic activity onto a standard chewing cycle which was created based on 15 unilateral chewing cycles. Paired t-test, one-way ANOVA and Student-Newman-Keuls post-test were used for comparisons. Although the Time to Peak for the balancing side SCM appeared shorter than for the other three tested muscles, most often it did not reach a level of significance. However, the location of the balancing side SCM's peak activity was further from the terminal chewing position ( TCP) than the working side SCM and bilateral masseters ( P < 0·05). The balancing side SCM activity reached its peak significantly further away from TCP than the other three tested muscles during chewing. Further studies with spatiotemporal variables included should be helpful to understand the roles of the head, neck and jaw muscles in orofacial and cervical dysfunctional problems. [ABSTRACT FROM AUTHOR]

The amount of alloy added during the LF refining process affects the hit rate of steel composition control. Therefore, improving the accuracy of the alloy addition amount can help improve efficiency and reduce production costs. To address the existing problem of inaccurate alloy addition in the refining process, the group established an alloy addition prediction model based on an improved whale swarm optimization algorithm and stochastic configuration network (LWOA-SCN) with the historical smelting data of a steel mill. The model can effectively improve the prediction accuracy and convergence speed of the model. The research results show that the model is more advantageous in improving the hit rate of alloy addition, which provides theoretical guidance for practical production. [ABSTRACT FROM AUTHOR]

The evolutions of localized states, dielectric functions, and electronic band structure for nitrogen (N) incorporated GeTe (NGT) as functions of temperature (210-660 K) and N concentration (0%-18%) have been investigated with the aid of temperature dependent spectroscopic ellipsometry experiments. The increased Urbach absorption energy, caused by band-tail localized states, can be attributed to the increment of structure defects with N concentration, which is generated from the N atoms bonding with Ge. Besides, the details of the dynamic crystallization process and the role of nitrogen in NGT films have been elucidated by the abnormal behavior of interband transition energy and the evolutions of surface morphology, namely, the nitrides separation before crystallization and the inhibition on GT crystallization. The dynamic crystallization process and the nitrogen behavior in NGT are of great significance for further study on the reliability and endurance of the NGT-based data storage devices. [ABSTRACT FROM AUTHOR]