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This paper investigates the buckling and vibration of heavy standing plates with rotational elastic edge constraints. The discrete singular convolution (DSC) method as a powerful numerical technique is applied to derive the governing eigenvalue equation. Convergence and comparison studies are conducted to authenticate the correctness and accuracy of the DSC approach. Accurate first-known vibration solutions for elastically restrained vertical plates subjecting to body forces/self-weight are presented. Some contour mode shapes for the vibration of elastically restrained vertical plates are also depicted for illustration. [ABSTRACT FROM AUTHOR]

Mitotic death is a major form of cell death in cancer cells that have been treated with chemotherapeutic drugs. However, the mechanisms underlying this form of cell death is poorly understood. Here, we report that the loss of chromosome integrity is an important determinant of mitotic death. During prolonged mitotic arrest, caspase-3 is activated and it cleaves Cap-H, a subunit of condensin I. The depletion of Cap-H results in the loss of condensin I complex at the chromosomes, thus affecting the integrity of the chromosomes. Consequently, DNA fragmentation by caspase-activated DNase is facilitated, thus driving the cell towards mitotic death. By expressing a caspase-resistant form of Cap-H, mitotic death is abrogated and the cells are able to reenter interphase after a long mitotic delay. Taken together, we provide new insights into the molecular events that occur during mitotic death. [ABSTRACT FROM AUTHOR]

Objective: The present study was carried out to explore the antinociceptive as well as the anti-inflammatory effects of an ethanol extract of Stachytarpheta jamaicensis (L.) Vahl (EESJ) using 3 models of nociception and 2 models of inflammation in experimental animals. Materials and Methods: EESJ was prepared by overnight soaking of the oven-dried (50°C; 72 h) ground leaves (500 g) in 80% ethanol (1:5; w/v). The filtrate was evaporated to dryness (50°C), resuspended in distilled water at concentrations to provide the desired doses of 50, 100 and 150 mg/kg. For antinociceptive effects, 3 models were used: acetic acid-induced abdominal writhing, hot-plate- and formalin-induced paw-licking tests; for anti-inflammatory effects, 2 models were used – carrageenan-induced paw edema and cotton-pellet-induced granuloma tests. Appropriate doses were administered intraperitoneally (i.p.) to mice/rats prior to each test. The mechanisms of antinociceptive action of the extract were also investigated by pretreatment with naloxone (5 mg/kg, i.p.). Results: The extract exhibited significant (p < 0.05) antinociceptive activity in all nociceptive models tested with dose-dependent activity observed using the abdominal writhing and formalin tests. Pretreatment with naloxone partially, but significantly (p < 0.05) reversed the antinociceptive activity of the extract when assessed using the abdominal-writhing- and formalin-induced paw-licking tests, and completely inhibited its activity when the hot-plate test was used. The extract also showed significant (p < 0.05) anti-inflammatory activity in both the acute (carrageenan-induced paw edema test) and the chronic (cotton-pellet granuloma test) tests. Conclusion: This study showed the potential of EESJ to exert antinociceptive and anti-inflammatory activities, the former being modulated via peripheral and central mechanisms and involving, in part, activation of the opioid receptor system. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

In this paper, a new harmonic balance approach for solving the large amplitude nonlinear vibration of an elastically-restrained beam with a point mass is introduced. The coupling of Newton's method with harmonic balancing takes the advantage of reducing the deficiency and complexity of the classical harmonic balance method in dealing with the nonlinear systems. Using the approach, accurate higher-order approximate analytical expressions for period and periodic solution are established. Results in non-dimensional forms are presented graphically to illustrate the effects of the base stiffness, position and magnitude of lumped mass on the variation of oscillation period and amplitude. Comparison with published results and numerical integration solutions shows that the accuracy of this new Newton-harmonic balance (NHB) approach is excellent while some published numerical solutions for specific examples are rather unsatisfactory. [ABSTRACT FROM AUTHOR]