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The aerodynamic characteristics of flapping rotary wings (FRWs) have received considerable attention in design. In this study, optimizations of aerodynamic performance and kinematics of FRWs over the parameter space are explored. A well-validated Quasi-Steady model is employed to estimate the aerodynamic characteristics of FRWs in hovering flight, and a genetic algorithm is utilized for optimizing. It is assumed that flapping and pitching motion are given by motion parameters actively, while rotation is produced passively. Our results show that the optimal kinematic parameters are independent of flapping frequencies. The maximum lift comes from the high rotational speed caused by the small pitching amplitude, and the maximum power factor is from the large pitching amplitude. The dimensionless optimization of the flapping velocity as reference velocity is comparable to the dimensional results. The optimization model proposed in this study can be applied to the actual model for qualitative analysis. Rotational equilibrium power factor can reach more than 80% of the maximum value without rotation equilibrium constraint, but which rotational status can achieve the maximum power factor depends on the pitching angle at the mid-downstroke (αd). This study is helpful for the kinematic parameter design and further research of FRWs. [ABSTRACT FROM AUTHOR]

Spinning joined conical-cylindrical shells (JCCSs) with bolt boundary constraints are widely used in rotor systems of aero-engines, and always operate in thermal environments. Under external excitation, the friction hysteresis phenomenon of bolt connections often occurs, and the high-temperature environment further changes the friction characteristics of the connection interface, making the vibration characteristics of the system nonlinear and complex. Till now, research on the nonlinear vibration of spinning JCCSs caused by bolt connections with the temperature effect is scarce. To address this problem, this study develops a nonlinear dynamic model of spinning JCCSs with bolt boundary constraints in a thermal environment for the first time. A novel equivalent mechanical model of the bolt connection is established, which is represented by the nonlinear stiffness and damping with amplitude and temperature-dependent characteristics. The energy expressions of spinning conical and cylindrical shell components are deduced by Donnell's shell theory. The rigid joint between the conical and cylindrical shells is realized via successive distributed artificial springs. The Chebyshev polynomials are adopted as the admissible functions, and the governing equation is obtained by the Lagrange equation. Then, by comparison with the available literature, finite element simulation, and experiment test, the accuracy of the established theoretical model is validated. The nonlinear vibration mechanism is illustrated from aspects of equivalent stiffness and equivalent damping. Finally, the effects of spinning speed and temperature on nonlinear vibrations of bolted JCCSs are further investigated. [ABSTRACT FROM AUTHOR]

Thermosensation is vital for the survival, propagation, and adaption of all organisms, but its mechanism is not fully understood yet. Here, we find that TMC6, a membrane protein of unknown function, is highly expressed in dorsal root ganglion (DRG) neurons and functions as a Gαq-coupled G protein-coupled receptor (GPCR)-like receptor to sense noxious heat. TMC6-deficient mice display a substantial impairment in noxious heat sensation while maintaining normal perception of cold, warmth, touch, and mechanical pain. Further studies show that TMC6 interacts with Gαq via its intracellular C-terminal region spanning Ser780 to Pro810. Specifically disrupting such interaction using polypeptide in DRG neurons, genetically ablating Gαq, or pharmacologically blocking Gαq-coupled GPCR signaling can replicate the phenotype of TMC6 deficient mice regarding noxious heat sensation. Noxious heat stimulation triggers intracellular calcium release from the endoplasmic reticulum (ER) of TMC6- but not control vector-transfected HEK293T cell, which can be significantly inhibited by blocking PLC or IP3R. Consistently, noxious heat-induced intracellular Ca2+ release from ER and action potentials of DRG neurons largely reduced when ablating TMC6 or blocking Gαq/PLC/IP3R signaling pathway as well. In summary, our findings indicate that TMC6 can directly function as a Gαq-coupled GPCR-like receptor sensing noxious heat. [ABSTRACT FROM AUTHOR]

The contact states including stick, slip, and separation can occur at the bolted joint interface of bolted flange joint structures, which significantly affects and complicates the vibration characteristics of connected structures. However, the mechanism of the influence of these three contact states on structural vibration is still not well understood. This paper establishes a universal theoretical model of bolted flange joint plate systems considering the stick, slip, and separation states simultaneously, which can be extended to a structure with an arbitrary number of bolts and plates. The bi-linear hysteretic model is adopted to model the three contact states. The contact pressure between the bolts and flanges is considered as two-dimensional distribution form, which is closer to real contact situation. Based on the Kirchhoff plate theory, the energy functions of plate and flange are obtained. Further, the nonlinear dynamic equation is derived using Lagrange equations, and solved by the Newmark-beta method. The experimental studies are performed on a plate system connected with bolted flange joint to illustrate the effectiveness of the theoretical model. The results highlight the influence of separation state and friction coefficient on the vibration response. It is found that as the tightening torque decreases, the resonance amplitude increases due to the occurrence of interface separation. The slip state can cause the nonlinear softening property, but this property will weaken when the separation occurs at bolted joint interfaces. [ABSTRACT FROM AUTHOR]

The thorax is the central component of the insect flight drivetrain, making it essential to understand how thoracic muscles influence insect flight for flapping wing microair vehicle design. This paper presents a theoretical model that takes into account the influence of thoracic muscles on flapping wing motion with reference to real insects. The thoracic muscle effect is simulated by the chordwise torsional spring, whose stiffness is derived from a comparison test with the results of real insect experiments. The elastic deformation of the flexible flapping wing is modeled by the von Kármán nonlinear plate theory. The predictive quasi-steady aerodynamic model based on the blade element theory can estimate the aerodynamic force, and the modeling of the spanwise bending and twisting is done with quadratic polynomials. The equations of motion are solved using the Newmark-Raphson method. Results suggest that including the influence of thoracic muscles decreases cycle-averaged lift and power, but enhances the efficiency of lift production by 23%. Moreover, it also postpones pitching motion and reduces its amplitude, though the movement trends of the flapping motion remain approximately unchanged regardless of the inclusion of the thoracic muscle effect. [ABSTRACT FROM AUTHOR]

In this paper, we are concerned with the precise relationship between the Hausdorff dimension of possible singular point set S of suitable weak solutions and the parameter α in the nonlinear term in the following parabolic equation h t + h x x x x + ∂ x x | h x | α = f. It is shown that when 5 / 3 ≤ α < 7 / 3 , the 3 α − 5 α − 1 dimensional parabolic Hausdorff measure of S is zero, which generalizes the recent corresponding work of Ozánski and Robinson in [SIAM J. Math. Anal., 51, 228–255 (2019)] for α = 2 and f = 0. The same result is valid for a 3D modified Navier–Stokes system. [ABSTRACT FROM AUTHOR]

In this study, analytical solutions are developed for the super-critical vibration of fluid-conveying pipes with elastic supports. By accounting for the geometric nonlinearity, the nonlinear buckling problem is solved and the equilibrium configurations are obtained. Using a coordinate transform, the dynamic model of a super-critical pipe is obtained for the vibrations around the non-trivial equilibrium configuration. The present analytical solutions of interest for the equilibrium configurations, the natural frequencies, the mode shape, and the transient response are obtained by combining the Laplace transform method with the complex mode method. The Laplace transform method is applied to formulate a steady-state Green's function solution. Using the complex mode methodology, vibration characteristics of the super-critical pipe around the equilibrium configurations are presented. The present analytical solutions can be readily reduced to classical boundary conditions by setting end-spring parameters to zero or infinity. Numerical simulations are conducted to understand the impact mechanisms of the elastic support parameters on the free and forced vibration characteristics. This work offers important guidance for optimization and design of super-critical fluid-conveying pipes with elastic supports for engineering applications. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pain is a common symptom of an illness. For decades, pain treatments such as non-steroidal anti-inflammatory drugs, opioids, and surgical nerve blocking have been widely used, but each method has its limitations. Photobiomodulation is a recently developed method for pain management, with light-emitting diodes (LEDs) being a more recent development used in pain management because of their low cost, low side effects, and high safety. Here, we reviewed the phototherapeutic effects of LEDs on different pain conditions. We also discussed possible physicochemical and neurobiological mechanisms underlying LED therapy, especially its effects on inflammatory pain. [ABSTRACT FROM AUTHOR]

Purpose: For the non-destructive interrogation purpose, the present work studies the flexural wave propagation characteristics in submerged pipes conveying viscous flowing fluid. The internal fluid-pipe and external fluid-pipe coupling effects are both considered. Methods: The internal fluid is assumed to be viscous, irrotational, and isotropic; and the external fluid is treated as ideal and irrotational. The pressures exerted on the pipe by the internal and external fluid can be derived via the Navier–Stokes equation. The pipe is modeled based on the first-order shear deformation shell theory. The motion equations of the submerged fluid-conveying pipe are given by the Hamilton's Principle. Results: The coupled equations of wave motion of the pipes are obtained based on the first-order shear deformation shell theory. The wave propagation relations of submerged pipes conveying viscous flowing fluid are given. Conclusion: Increasing internal fluid velocity, external fluid velocity, or reducing internal fluid mass density can result in an increase in phase velocity of the first flexural mode. In addition, the phase velocities of the first three flexural modes are almost constant under a large axial wave number. [ABSTRACT FROM AUTHOR]

This work analyzes the free vibration of a spinning functionally graded graphene platelet-reinforced metal foam (FG-GPLRMF) beam. The differential transformation method is extended to analyze flap-wise bending vibration and chordwise bending vibration with Coriolis force effect for the first time. The beam is modeled using the Euler–Bernoulli beam theory. The Halpin–Tsai micromechanics model is utilized to predict effective material properties. Various types of graphene platelet (GPL) and porosity distributions are considered. The governing equations and corresponding boundary conditions of the FG-GPLRMF beam are obtained via Hamilton's principle. Results show that the vibration characteristics of the FG-GPLRMF beam are affected by the GPL geometry size, types of porosity, and GPL distributions. Among different types of porosity, the Porosity-A causes the highest fundamental natural frequency, while the Porosity-B corresponds to the lowest one of the spinning FG-GPLRMF beam in most cases. Moreover, the GPL pattern and porosity distribution have a coupled effect on the bending vibration of the spinning FG-GPLRMF beam. [ABSTRACT FROM AUTHOR]

The theoretical modeling of a functionally graded (FG) graphene nanoplatelet (GPL)-reinforced assembled beam–plate structure resting on elastic supports is presented for the first time, and its free vibration analysis is performed. Herein, the assembled structure is modeled according to the Kirchhoff plate theory and the Rayleigh beam theory. The graphene nanoplatelets (GPLs) gradiently distribute in the beam's radial direction and in the plate's thickness direction, respectively. By adopting the rule of mixture and the Halpin–Tsai model, the effective material properties can be obtained. By employing the Lagrange's equation and considering the effects of Coriolis force and centrifugal force, the coupled governing equations of the assembled structure are determined. Furthermore, the assumed modes method and substructure modal synthesis method are applied to obtain the frequencies of the assembled beam–plate structure. A comprehensive numerical investigation is carried out to discuss the influence of the structural and material parameters on the vibration behavior of the beam–plate structure. [ABSTRACT FROM AUTHOR]

In this study, the dynamic response of buried fluid-conveying pipelines subjected to blast loading using the Love shell theory has been investigated. The fluid is considered as ideal fluid, and the velocity potential is used to describe the fluid pressure acting on the pipeline. The governing equations of the buried fluid-conveying pipelines are derived through Hamilton's principle. The modal superposition method and the Newmark integral method are used to analyze the dynamic response of the pipelines under blast loading. Results show that the displacement amplitudes of the pipelines are larger in the soil with a higher acoustic impedance. The Winkler foundation can enhance the stiffness of the pipelines. Moreover, the increase in the scaled distance leads to the decrease in the displacement amplitudes of the pipelines. The increase in the fluid velocity results in the rise of the displacement amplitudes of the pipelines. In addition, the maximum displacement increases first and then decreases with the increase in length-to-radius ratio of the pipelines. With the increase in thickness-to-radius ratio, the maximum displacement of the pipelines tends to decrease. [ABSTRACT FROM AUTHOR]

In the present study, we analyze the nonlinear forced vibration of thin-walled metal foam cylindrical shells reinforced with functionally graded graphene platelets. Attention is focused on the 1:1:1:2 internal resonances, which is detected to exist in this novel nanocomposite structure. Three kinds of porosity distribution and different kinds of graphene platelet distribution are considered. The equations of motion and the compatibility equation are deduced according to the Donnell's nonlinear shell theory. The stress function is introduced, and then, the four-degree-of-freedom nonlinear ordinary differential equations (ODEs) are obtained via the Galerkin method. The numerical analysis of nonlinear forced vibration responses is presented by using the pseudo-arclength continuation technique. The present results are validated by comparison with those in existing literature for special cases. Results demonstrate that the amplitude–frequency relations of the system are very complex due to the 1:1:1:2 internal resonances. Porosity distribution and graphene platelet (GPL) distribution influence obviously the nonlinear behavior of the shells. We also found that the inclusion of graphene platelets in the shells weakens the nonlinear coupling effect. Moreover, the effects of the porosity coefficient and GPL weight fraction on the nonlinear dynamical response are strongly related to the porosity distribution as well as graphene platelet distribution. [ABSTRACT FROM AUTHOR]

Trigeminal neuralgia is a debilitating condition, and the pain easily spreads to other parts of the face. Here, we established a mouse model of partial transection of the infraorbital nerve (pT-ION) and found that the Connexin 36 (Cx36) inhibitor mefloquine caused greater alleviation of pT-ION-induced cold allodynia compared to the reduction of mechanical allodynia. Mefloquine reversed the pT-ION-induced upregulation of Cx36, glutamate receptor ionotropic kainate 2 (GluK2), transient receptor potential ankyrin 1 (TRPA1), and phosphorylated extracellular signal regulated kinase (p-ERK) in the trigeminal ganglion. Cold allodynia but not mechanical allodynia induced by pT-ION or by virus-mediated overexpression of Cx36 in the trigeminal ganglion was reversed by the GluK2 antagonist NS102, and knocking down Cx36 expression in Nav1.8-expressing nociceptors by injecting virus into the orofacial skin area of Nav1.8-Cre mice attenuated cold allodynia but not mechanical allodynia. In conclusion, we show that Cx36 contributes greatly to the development of orofacial pain hypersensitivity through GluK2, TRPA1, and p-ERK signaling. [ABSTRACT FROM AUTHOR]

It is very significant to improve the diameter accuracy of micro-shafts fabricated by micro-electrical discharge machining (micro-EDM) in micro-tools application. The diameter accuracy includes the uniformity of a single micro-shaft in axial direction and the repeatability of micro-shafts with the same diameter. A newly proposed method, named twin-mirroring-wire tangential feed electrical discharge grinding (TMTF-WEDG), can realize high uniformity and repeatability of micro-shafts via tangentially feeding and constraining of a narrow slit formed by a twin-mirroring-wire on the diameter of micro-shafts, respectively. Controlling the material removal thickness in single-step machining of micro-shafts is necessary to achieve high uniformity and repeatability. This paper focuses on the effects of the several important factors on the material removal thickness of micro-shafts to reveal the effects on the diameter uniformity and repeatability, including the open voltage, capacitance, feed rate in the Z-direction, feed step in the Y-direction, and tangential feed distance. The results indicate that the lower open voltage or the smaller capacitance or higher Z-direction feed rate, the smaller the thickness of the material removed, which is advantageous for controlling the consistency and repeatability of the micro-shafts. Decreasing of Y-direction feed step from 20 to 5 μm is accompanied by a reduction in material removal thickness, and the material removal thickness of less than 0.4 μm is achieved with a smaller feed step of in the Y-direction. As the tangential feed distance S2 decreases, the material removal thickness of the micro-shafts decreases gradually. In this study, the uniformity and repeatability of brass and tungsten micro-shafts are controlled within 1 μm and 2 μm, respectively. [ABSTRACT FROM AUTHOR]

This work investigates the wave dispersion characteristics in viscoelastic lipid nanotubes conveying protein solution. The protein solution is assumed to be viscous, incompressible, and irrotational. The theoretical formulation is within the framework of the Rayleigh beam theory and the nonlocal strain gradient theory (NSGT). The analytical wave dispersion relations of protein-conveying lipid nanotubes are obtained. Results show that the nonlocal parameter, the material length-scale parameter, the fluid mass density, and the damping coefficient have important effect on wave dispersion characteristics of viscoelastic lipid nanotubes conveying protein solution. These findings are helpful to understand the wave dispersion characteristics of protein-conveying lipid nanotubes. [ABSTRACT FROM AUTHOR]

In this paper, free vibration of a metal foam core sandwich (MFCS) beam embedded in Winkler–Pasternak elastic foundation is studied using the Chebyshev collocation method (CCM). This method can achieve high precision within the range allowed by the effective number of bits of computers. Three foam distribution types along the thickness direction are considered for the core. The Timoshenko beam theory is adopted and Hamilton's principle is utilized to derive the boundary conditions and governing equations of the model. The numerical results show that natural frequencies of the sandwich beam initially increase and then decrease with the rise in thickness of metal foam core. By arranging the foam distribution in the core, natural frequencies of the sandwich beam can be significantly changed. Moreover, natural frequencies of the uniform foam distribution beam are insensitive to the foam coefficient. For the beam with non-uniform foam distribution, however, the natural frequencies increase or decrease with the foam coefficient, depending closely on the foam type. In addition, the present method is validated by comparing with the published ones for special cases. [ABSTRACT FROM AUTHOR]

In this work, vibration and stability of fluid-conveying lipid nanotubes are investigated. The first-order shear deformation theory and the nonlocal strain gradient theory are adopted in the model. By using Hamilton's principle, the governing equations of the present system are obtained. In order to analyze the eigenvalue problem, the modal expansion method is used. Results show that the nonlocal parameter, the length-to-radius ratio, the flow velocity, the material length scale parameter and the solution density have important effect on the free vibration of fluid-conveying lipid nanotubes. Additionally, the current method is validated by comparing with the literature for special cases. The obtained results can be used for the biological application and design of fluid-conveying lipid nanotubes. [ABSTRACT FROM AUTHOR]

In this paper, free vibrations of cylindrical nanoshells made of nanoporous metal foam are investigated for the first time. Based on the modified couple stress theory and Love's thin shell theory, the governing equations of the present system are derived by using Hamilton's principle. Two types of nanoporosity distribution are considered in the construction of the nanoporous shells. Then, the Navier method and Galerkin method are utilized to solve natural frequencies of the nanoporous shells under different boundary conditions. Afterwards, a detailed parametric study is conducted. Results show that the nanoporosity type, the material length scale parameter, the porosity coefficient, the length-to-radius ratio, and the radius-to-thickness ratio play important role on the free vibrations of nanoporous shells. To check the validity of the present analysis, the results are compared with those in previous studies for the special cases. [ABSTRACT FROM AUTHOR]

This study investigates the free vibration of metal foam circular cylindrical shells under various boundary conditions. The elasticity modulus and mass density of the shells vary gradually and continually in the thickness direction. Two types of porosity distribution are taken into account including symmetrical and unsymmetrical distributions. Love's shell theory is employed to formulate the governing equations and then the Rayleigh–Ritz method is utilized to solve natural frequencies of the system. The results show that the porosity coefficient has important effect on the natural frequencies of metal foam shells. Its effect also relates to the boundary conditions of the shells. Moreover, different porosity distributions make the metal foam shells possess different vibration characteristics, which is quite obvious at large porosity coefficient. As the circumferential wave number increases, the natural frequencies of the metal foam shells tend to the same under various boundary conditions. Additionally, the present results are verified by the comparison with the published ones in the literature. [ABSTRACT FROM AUTHOR]

This study investigates vibration characteristics of longitudinally moving sigmoid functionally graded material (S-FGM) plates containing porosities. Two types of porosity distribution, i.e., the even and uneven distributions, are taken into account. In accordance with the sigmoid distribution rule, the material properties of porous S-FGM plates vary smoothly along the plate thickness direction. The nonlinear geometrical relations are adopted by using the von Kármán non-linear plate theory. Based on the d’Alembert’s principle, the nonlinear governing equation of the system is derived. Then, the governing equation is discretized to a set of ordinary differential equations via the Galerkin method. These discretized equations are subsequently solved by using the method of harmonic balance. Analytical solutions are verified with the aid of the adaptive step-size fourth-order Runge-Kutta method. By using the perturbation technique, the stability of the steady-state response is highlighted. Finally, both natural frequencies and nonlinear forced responses of moving porous S-FGM plates are examined. Results demonstrate that the moving porous S-FGM plates exhibit hardening spring characteristics in the nonlinear frequency response. Moreover, it is shown that the type of porosity distribution, moving speed, porosity volume fraction, constituent volume fraction and in-plane pretension all have significant influence on the nonlinear forced responses of moving porous S-FGM plates. [ABSTRACT FROM AUTHOR]

Accumulating evidence suggests that obesity is associated with chronic pain. However, whether obesity is associated with acute inflammatory pain is unknown. Using a well-established obese mouse model induced by a high-fat diet, we found that: (1) the acute thermal pain sensory threshold did not change in obese mice; (2) the model obese mice had fewer nociceptive responses in formalin-induced inflammatory pain tests; restoring the obese mice to a chow diet for three weeks partly recovered their pain sensation; (3) leptin injection induced significant phosphorylation of STAT3 in control mice but not in obese mice, indicating the dysmodulation of topical leptin-leptin receptor signaling in these mice; and (4) leptin-leptin receptor signaling-deficient mice (ob/ob and db/db) or leptin-leptin receptor pathway blockade with a leptin receptor antagonist and the JAK2 inhibitor AG 490 in wild-type mice reduced their nociceptive responses in formalin tests. These results indicate that leptin plays a role in nociception induced by acute inflammation and that interference in the leptin-leptin receptor pathway could be a peripheral target against acute inflammatory pain. [ABSTRACT FROM AUTHOR]

Congenital skeletal deformity of fetus varies and may be attributed to a range of reasons. Congenital skeletal deformity seriously affects body function or even leads to neonatal death directly. The disease brings great pain to victim and their family. We reviewed the fetal prenatal ultrasonic data conducted during period from Jan. 2013 to June 2016, and there were 84 fetuses with skeletal abnormalities among 12 000 cases, and 3 fetuses with thanatophoric dysplasia. Our report described and reviewed three common types of thanatophoric dysplasia, aiming to explore the value of standardized prenatal ultrasonic diagnosis of fetal abnormalities in the skeletal system. [ABSTRACT FROM AUTHOR]

The multi-objective genetic algorithm (MOGA) is proposed to calibrate the non-linear camera model of a space manipulator to improve its locational accuracy. This algorithm can optimize the camera model by dynamic balancing its model weight and multi-parametric distributions to the required accuracy. A novel measuring instrument of space manipulator is designed to orbital simulative motion and locational accuracy test. The camera system of space manipulator, calibrated by MOGA algorithm, is used to locational accuracy test in this measuring instrument. The experimental result shows that the absolute errors are [0.07, 1.75] mm for MOGA calibrating model, [2.88, 5.95] mm for MN method, and [1.19, 4.83] mm for LM method. Besides, the composite errors both of LM method and MN method are approximately seven times higher that of MOGA calibrating model. It is suggested that the MOGA calibrating model is superior both to LM method and MN method. [ABSTRACT FROM AUTHOR]

The title complex, {[Zn(ODIB)( bpdc)]·2DMF} was prepared under hydrothermal conditions (dimethylformamide and water) based on two ligands, namely, 1,1′-oxy-bis[3,5-diimidazolyl-benzene] (ODIB) and biphenyldicarboxylic acid (H bpdc). ODIB ligands link Zn cations to give layers in crystal. bpdc anions coordinate to Zn atoms, however, their introduction does not increase the dimension of the structure. Each layer is partially passes through the adjacent layers in the offset ABAB manner. [ABSTRACT FROM AUTHOR]

In microelectrical discharge machining (μEDM), the machining repeatability of microshafts with the same diameter is low due to the complex and stochastic nature of sparking. To improve machining repeatability, the effects of the main error sources on diameter accuracy of microshafts fabricated by wire electrical discharge grinding (WEDG) were analyzed. Strategies to minimize diameter differences between the target microshaft and the microshaft finally obtained by semifinishing and finishing were then proposed. Determining an appropriate infeed (depth of a cut) according to the desired erosion depth in the radial direction (Δ R) of microshafts was chosen as the control strategy for the semifinishing of microshafts produced by WEDG. To determine the infeed, empirical models that evaluate the relationship between the infeed and Δ R were developed through a large number of experiments. For the finishing of microshafts using WEDG, machining strategies such as zero infeed and stopping the wire electrode running, were proposed to eliminate some of the inherent errors. Finally, the empirical models developed for determining the infeed were verified by the successful fabrication of a stepped microshaft, which has small deviations from its desired diameters. By employing the developed empirical models and machining strategies, diameters of 26 out of 28 microshafts fabricated were found to lie in the range of 45 ± 2 μm. The experimental results verify that the diameter control strategies are effective and can be used to improve machining repeatability. [ABSTRACT FROM AUTHOR]

The NLRP3 inflammasome, which consists of the NLRP3 (nucleotide-binding oligomerization domain (Nod)-like receptor 3) scaffold, the ASC (apoptosis-associated speck-like protein containing a CARD) adaptor and procaspase- 1, is assembled after the cytoplasmic LRRs (leucine-rich repeats) of NLRP3 sense pathogens or danger signals. The NLRP3 inflammasome controls the activation of the proteolytic enzyme caspase-1. Caspase-1 in turn regulates the maturation of the proinflammasome cytokines IL-1β and IL-18, which leads to an inflammatory response. The inflammasome plays an important role in the development of Alzheimer’s disease and bacterial meningitis, and the NLRP3 inflammasome may become a new target for the prevention and treatment of central nervous system diseases. [ABSTRACT FROM AUTHOR]

It has been reported that Toll-like receptor 4 (TLR4), which plays an important role in glial activation in neuropathic pain, is significantly increased in cancer pain. The present study was designed to assess the role of TLR4 in cancer-induced bone pain (CIBP) by intrathecal administration of TLR4 signaling pathway blocker naloxone or lipopolysaccharide Rhodobacter sphaeroides (LPS-RS). The rats developed significant mechanical allodynia from day 8 after intratibial Walker 256 inoculation. Intrathecal injection of naloxone or LPS-RS at day 8 significantly attenuated mechanical allodynia as shown by increased paw withdrawal thresholds. In contrast, the same pharmacological treatment showed no or slight pain relieving effect at day 16. Our findings demonstrate that the spinal TLR4 signaling pathway contributes to the mechanism underlying CIBP in a stage-dependent manner in rats, and it may be an efficacious target at early stage for the treatment in the future. [ABSTRACT FROM AUTHOR]

The features of brucine (BC) binding to two blood proteins, bovine hemoglobin (BHb), and bovine serum albumin (BSA), were investigated via fluorescence, circular dichroism and UV/Vis absorption spectroscopy. The results revealed that BC caused the fluorescence quenching of blood proteins by the formation of BC-protein complex. The corresponding thermodynamic parameters were measured at different temperatures. The process of binding BC molecule on protein was a spontaneous molecular interaction procedure in which entropy increased and Gibbs free energy decreased. Hydrophobic and electrostatic interactions play a major role in stabilizing the complex. The molecular docking has been employed to explore the binding site of the BC in BHb and BSA on the Autodock 4.2. The distances r between BC and protein were calculated to be 4.93 and 5.08 nm for BHb, and BSA, respectively. The effect of BC on the conformation of blood proteins was analyzed using CD, synchronous fluorescence and three-dimensional fluorescence spectra. [ABSTRACT FROM AUTHOR]

Copyright of Neuroscience Bulletin is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

CD40/CD40 ligand (CD40L) interaction plays an essential role in cell-mediated immune responses. We examined whether expression of CD40L in murine lung carcinoma (A11) cells could produce antitumor effects. The proliferation rate in vitro of A11 cells transfected with the murine CD40L gene (A11/CD40L) was not different from that of parent cells; however, half of the immunocompetent mice inoculated with A11/CD40L cells did not form tumors and the growth of A11/CD40L tumors developed in the rest of mice was significantly retarded compared with that of parent tumors. Protective immunity was also induced in the mice that had rejected A11/CD40L cells. In T-cell-defective nude mice, these antitumor effects were not observed. Bone-marrow-derived dendritic cells (DCs), when cultured with A11/CD40L cells, formed clusters with the tumors and showed upregulated CD86 expression. Expression of the interleukin-23 (IL-23) p19, IL-12p35, IL-18, interferon-γ (IFN-γ) and Mig (monokine induced by IFN-γ) genes was induced in the DCs that were cultured with A11/CD40L but not with A11 cells, and P40, the subunit of both IL-12 and IL-23, was secreted from the cocultured DCs. These data directly showed that the expression of CD40L in tumors facilitated the interaction between DCs and the tumors, enhanced the maturation of DCs, induced secretion of cytokines, and consequently produced T-cell-dependent systemic immunity. [ABSTRACT FROM AUTHOR]

Interleukin-21 (IL-21) is a novel cytokine that can induce proliferation of activated T cells and maturation of natural killer (NK) cells. We therefore examined whether expression of the IL-21 gene in tumor cells could generate antitumor responses. Murine colon carcinoma Colon 26 cells that were transduced with the mouse IL-21 gene (Colon 26/IL-21) were rejected in syngeneic mice and the mice subsequently acquired protective immunity. The growth of Colon 26/IL-21 tumors developed in nude mice was retarded compared with that of parent tumors, and this growth suppression was not observed in nude mice that were treated with anti-asialo GM[SUB1] antibody. Spleen cells from the mice that had rejected Colon 26/IL-21 cells showed cytotoxic activity to Colon 26 but not to irrelevant tumor cells, and produced larger amounts of interferon-γ upon stimulation with irradiated Colon 26 cells. Spleen cells from Colon 26/IL-21-tumor- but not parent-tumor-bearing mice had lytic activity to YAC-1 cells. These data suggest that expression of IL-21 in tumors induces T- and NK-cell-dependent antitumor effects. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Acupuncture & Tuina Science is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)