An efficient Galerkin averaging-incremental harmonic balance (EGA-IHB) method is developed for steady-state nonlinear dynamic analysis of index-3 differential algebraic equations (DAEs) for general ...rigid multibody systems. The multibody dynamic modeling theory has made significant advances in generality and simplicity, and multibody systems are usually governed by DAEs. The bridge between the multibody dynamic modeling theory and nonlinear dynamic analysis theory is built for the first time in this work, and the EGA-IHB method can be used as a universal solver for obtaining steady-state periodic responses of DAEs for general multibody systems. Since the fast Fourier transform and EGA are used, the EGA-IHB method has excellent robustness. Since the Floquet theory cannot be directly used for stability analysis of periodic responses of DAEs, a new stability analysis procedure is developed, where perturbed, linearized DAEs are reduced to ordinary differential equations with use of independent generalized coordinates. A modified arc-length continuation method with a scaling strategy is proposed for calculating response curves and conducting parameter studies. Several examples are used to show the performance and capability of the current method. Periodic solutions of DAEs from the EGA-IHB method show excellent agreement with those from numerical integration methods. Amplitude–frequency and amplitude–parameter response curves are generated, and stability and period-doubling bifurcations are analyzed. The current method shows excellent computational efficiency and robustness in solving high-dimensional DAEs.
Perovskite SrIrO3 has long been proposed as an exotic semimetal induced by the interplay between the spin-orbit coupling and electron correlations. However, its low-lying electronic structure is ...still lacking. We synthesize high-quality perovskite SrIrO3 (100) films by means of oxide molecular beam epitaxy, and then systemically investigate their low energy electronic structure using in-situ angle-resolved photoemission spectroscopy. We find that the hole-like bands around R and the electron-like bands around U(T) intersect the Fermi level simultaneously, providing the direct evidence of the semimetallic ground state in this compound. Comparing with the density functional theory, we discover that the bandwidth of states near Fermi level is extremely small, and there exists a pronounced mixing between the Jeff = 1/2 and Jeff = 3/2 states. Moreover, our data reveal that the predicted Dirac degeneracy protected by the mirror-symmetry, which was theoretically suggested to be the key to realize the non-trivial topological properties, is actually lifted in perovskite SrIrO3 thin films. Our findings pose strong constraints on the current theoretical models for the 5d iridates.
This work aims to investigate experimentally the effect of the Reynolds number Re, based on the nozzle diameter D, on jet mixing manipulation using an unsteady radial minijet. A novel artificial ...intelligence (AI) control system has been developed to manipulate the jet over Re = 5800–40 000. The system may optimize simultaneously the control law and a time-independent parameter, which dictate the actuation ON/OFF states and amplitude, respectively. The control parameters include the mass flow rate, excitation frequency and diameter ratios (Cm, fe/f0 and d/D) of the minijet to the main jet as well as the duty cycle (α) of minijet injection. Jet mixing is quantified using Ke and K0, where K is the decay rate of the jet centreline mean velocity, and subscripts e and 0 denote the manipulated and unforced jets, respectively. It has been found that the maximum Ke achievable does not vary with Re. Scaling analysis of the huge volume of experimental data obtained from the AI system reveals that the relationship Ke = g1 (Cm, fe/f0, α, d/D, Re, K0) may be reduced to Ke/K0 = g2 $(\zeta )$, where g1 and g2 are different functions and the scaling factor $\zeta = ({C_m}/\alpha ){(D/d)^{1 - n}}(1/Re){({f_e}/{f_{e,opt}})^m}$, m and 1 − n are the power indices, and subscript opt denotes the value at which Ke is maximum. The scaling law is discussed in detail, along with the physical meanings of the dimensionless parameters Ke/K0, ζ, $({C_m}/\alpha ){(D/d)^{1 - n}}(1/Re)$ and ${({f_e}/{f_{e,opt}})^m}$.
Nilotinib (Tasigna) is a BCR-ABL1 tyrosine kinase inhibitor approved for the treatment of patients with Philadelphia chromosome-positive chronic myeloid leukemia in chronic phase (CML-CP) who are ...newly diagnosed or intolerant of or resistant to imatinib. The 48-month follow-up data for patients with CML-CP treated with nilotinib after imatinib resistance or intolerance on an international phase II study were analyzed. Overall, 59% of patients achieved major cytogenetic response; 45% achieved complete cytogenetic response while on study. The estimated rate of overall survival (OS) and progression-free survival (PFS) at 48 months was 78% and 57%, respectively. Deeper levels of molecular responses at 3 and 6 months were highly positively correlated with long-term outcomes, including PFS and OS at 48 months. Of the 321 patients initially enrolled in the study, 98 (31%) were treated for at least 48 months. Discontinuations were primarily due to disease progression (30%) or adverse events (21%). Nilotinib is safe and effective for long-term use in responding patients with CML-CP who are intolerant of or resistant to imatinib. Further significant improvements in therapy are required for patients who are resistant or intolerant to imatinib.
A new formulation is developed for dynamic analysis of a rotating planar Timoshenko beam. The configuration of Timoshenko beam is described using its slope angle and axial and shear strains; hence, ...the shear locking problem can be naturally avoided. Nonlinear partial differential equations of the rotating hub–beam system and associated boundary conditions are derived using Hamilton’s principle. While six boundary conditions are needed for choice of trial functions of three dependent variables, there are only four boundary conditions that can be determined and two boundary conditions are undetermined. An accurate global spatial discretization method is used, where dependent variables are divided into internal and boundary-induced terms. Internal terms only need to satisfy homogeneous boundary conditions, which can be easily chosen as trigonometric functions. Boundary-induced terms are interpolated using dependent variables at boundaries that are taken as generalized coordinates. Nonlinear governing ordinary differential equations of the system are obtained using Lagrange’s equations. When the hub rotates at a constant angular velocity, nonlinear governing equations can be linearized for vibration analysis, and dimensionless vibration equations of the beam are obtained. Natural frequencies and mode shapes of the beam with a constant angular velocity are calculated and compared with available results in the literature. Frequency veering and mode shift phenomena occur. Nonlinear dynamic responses of the system are then calculated and compared with those from the commercial software ADAMS, and they are in good agreement. Axial and shear strains of the beam and their spatial derivatives are also calculated. Since trial functions in the assumed modes method cannot satisfy undetermined boundary conditions, inaccurate results of strains and their spatial derivatives are obtained using the assumed modes method. Hence, use of the accurate global spatial discretization method in the current formulation is essential here.
This study further evaluated the
and
anti-
activities and potential underlying mechanism of patchouli alcohol (PA), a tricyclic sesquiterpene. In the
assay, the capacities of PA to inhibit and kill
...were tested on three standard strains at different pH values and on 12 clinical isolates. The effects of PA on
adhesion (and its
,
, and
genes), motility (and its
and
genes), ultrastructure, and flagellation were investigated. Moreover, the
resistance to and postantibiotic effect (PAE) of PA were determined. Furthermore, the
effects of PA on
eradication and gastritis were examined. Results showed that MICs of PA against three standard strains (pH 5.3 to 9) and 12 clinical isolates were 25 to 75 and 12.5 to 50 μg/ml, respectively. The killing kinetics of PA were time and concentration dependent, and its minimal bactericidal concentrations (MBCs) were 25 to 75 μg/ml. In addition,
adhesion, motility, ultrastructure, and flagellation were significantly suppressed. PA also remarkably inhibited the expression of adhesion genes (
and
) and motility genes (
and
). Furthermore, PA treatment caused a longer PAE and less bacterial resistance than clarithromycin and metronidazole. The
study showed that PA can effectively eradicate
, inhibit gastritis, and suppress the expression of inflammatory mediators (COX-2, interleukin 1β, tumor necrosis factor alpha, and inducible nitric oxide synthase iNOS). In conclusion, PA can efficiently kill
, interfere with its infection process, and attenuate gastritis with less bacterial resistance, making it a potential candidate for new drug development.
Soft sensors that can discriminate shear and normal force could help provide machines the fine control desirable for safe and effective physical interactions with people. A capacitive sensor is made ...for this purpose, composed of patterned elastomer and containing both fixed and sliding pillars that allow the sensor to deform and buckle, much like skin itself. The sensor differentiates between simultaneously applied normal force and shear using summation and differences of signals from four deformable capacitors. Cross talk from shear to normal force is less than 2.5%, and between shear axes is less than 10%. Normal and shear stress sensitivity is 0.49 kPa and 0.31 kPa respectively, with a minimum displacement resolution of 40 μm. In addition, finger proximity is detectable at a range of up to 15 mm. The operation is demonstrated on a simple gripper holding a cup. The combination of features and the straightforward fabrication method make this sensor a candidate for implementation as a sensing skin for humanoid robotics applications.
Our recent study observed that the expression of ubiquitin D (UBD), a member of ubiquitin-like modifier family, was upregulated in colon cancer parenchymal cells. The present study further ...investigated the clinical signicance of UBD in colon cancer.
Using quantitative PCR, tissue microarray (TMA), western blot analysis and immunohistochemical stain, we evaluated UBD mRNA and protein levels in tumour tissues from patients with colon cancer at different stages and in paired adjacent normal epithelium.
Immunohistochemical detection of UBD on a TMA containing 203 paired specimens showed that increased cytoplasmic UBD was signicantly associated with depth of cancer invasion, lymph node metastasis, distant metastasis, tumour histologic grade, advanced clinical stage and Ki-67 proliferative index. Patients with UBD-positive tumours had a significantly higher disease recurrence rate and poorer survival than patients with UBD-negative tumours after the radical surgery. Stratification analysis according to tumour stage revealed UBD as an independent predictor for tumour recurrence in patients with stage II and III tumours.
UBD may contribute to the progression of colon carcinogenesis and function as a novel prognostic indicator of forecasting recurrence of stage II and III patients after curative operations.
Deriving the strength and direction of the three-dimensional (3D) magnetic field in the solar atmosphere is fundamental for understanding its dynamics. Volume information on the magnetic field mostly ...relies on coupling 3D reconstruction methods with photospheric and/or chromospheric surface vector magnetic fields. Infrared coronal polarimetry could provide additional information to better constrain magnetic field reconstructions. However, combining such data with reconstruction methods is challenging, e.g., because of the optical thinness of the solar corona and the lack and limitations of stereoscopic polarimetry. To address these issues, we introduce the data-optimized coronal field model (DOCFM) framework, a model-data fitting approach that combines a parameterized 3D generative model, e.g., a magnetic field extrapolation or a magnetohydrodynamic model, with forward modeling of coronal data. We test it with a parameterized flux-rope insertion method and infrared coronal polarimetry where synthetic observations are created from a known "ground-truth" physical state. We show that this framework allows us to accurately retrieve the ground-truth 3D magnetic field of a set of force-free field solutions from the flux-rope insertion method. In observational studies, the DOCFM will provide a means to force the solutions derived with different reconstruction methods to satisfy additional common coronal constraints. The DOCFM framework therefore opens new perspectives for the exploitation of coronal polarimetry in magnetic field reconstructions and for developing new techniques to more reliably infer the 3D magnetic fields that trigger solar flares and coronal mass ejections.
An accurate singularity-free geometrically exact formulation of a three-dimensional beam with large displacements, large deformations, and large rotations is developed. The undeformed configuration ...of the beam can be either straight or curved. Euler parameters are used to parametrize the rotation of a cross section of the beam to avoid singularity. While the position vector is interpolated using Hermite functions, Euler parameters are interpolated using a
C
1
-continuous interpolation function. The stretch–shear strain vector of the centroid line of the beam can be obtained by independent interpolations of position and rotation fields. Governing equations of the beam are obtained using Lagrange’s equations for systems with constraints. An arc-length method is introduced to trace the force–displacement curve of equilibria of the beam. Several examples are simulated to show the performance of the current formulation. A static planar example with its exact solution is first simulated to show accuracy and convergency of the current formulation. In-plane buckling of a circular arch is then studied, and the snap-through phenomenon is found when the arch has clamped–clamped boundary conditions. The stiffness, natural frequencies, and mode shapes of a spring are calculated; the effect of the mass of the spring on natural frequencies and mode shapes of the spring–mass system is analyzed, and a curve veering phenomenon accompanied with mode shift and mode localization behaviors is found there. The current formulation is compared with the formulation in the commercial software ADAMS using a dynamic three-dimensional example, and their results are in excellent agreement. Another dynamic example of a moving force on a beam is also shown, and its dynamic behavior is analyzed.
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