THREE-DIMENSIONAL FINITE ELEMENT ANALYSIS OF STRESS RESPONSE IN ADHESIVE BUTT JOINTS SUBJECTED TO IMPACT BENDING MOMENTS

The stress wave propagation and the stress distribution in adhesive butt joints of T-shaped similar adherends subjected to impact bending moments are calculated using a three-dimensional finite-element method (FEM). An impact bending moment is applied to a joint by dropping a weight. The FEM code employed is DYNA3D. The effects of the Young's modulus of adherends, the adhesive thickness, and the web length of T-shaped adherends on the stress wave propagation at the interfaces are examined. It is found that the highest stress occurs at the interfaces. In the case of T-shaped adherends, it is seen that the maximum principal stress at the interfaces increases as Young's modulus of the adherends increases. In the special case where the web length of T-shaped adherends equals the flange length, the maximum principal stress at the interfaces increases as Young's modulus of the adherends decreases. The maximum principal stress at the interfaces increases as the adherend thickness decreases. The characteristics of the T-shaped adhesive joints subjected to static bending moments are also examined by FEM and compared with those under impact bending moments. Furthermore, strain response of adhesive butt joints was measured using strain gauges. A fairly good agreement is observed between the numerical and the experimental results.     

Effect of matrix metalloproteinase inhibitor on experimental pseudomonal corneal ulceration

We examined the effect of matrix metalloproteinase (MMP) inhibitor (CS-610) on experimental pseudomonal corneal ulceration by clinical and histological evaluation. Intrastromal injection of 3.5 microliters sterile culture broth of P. aeruginosa, IID-1117 (13.5 unit Type I collagenase equivalent proteinase activities), was done to induce corneal ulcers in guinea pigs. The animals were divided into two groups of 23 each. The CS-610 group received topical CS-610 (400 micrograms/ml) treatment at 2-hour intervals and the control group received only the vehicle of CS-610 at the same intervals. In the control group, corneas developed acute corneal damage following corneal ulcerations at 6-12 hours. In the CS-610 group, these corneal lesions were inhibited in most of the eyes (p < 0.01). In the late period, as inflammatory cells migrated into the cornea, some animals of the CS-610 group developed corneal ulcer. The results indicated that CS-610 had a potent inhibitory activity against pseudomonal proteinases in vivo. The results also suggested that the mechanism of the ulceration model involved not only pseudomonal proteinases but also endogenous responses.     

Carbon tax for subsidizing photovoltaic power generation systems and its effect on carbon dioxide emissions

This paper proposes a new framework for evaluating quantitatively the effect of carbon taxation. In this study, the tax revenues are supposed to be used only as a subsidy for installing Photovoltaic Power Generation (PV) Systems on houses. The evaluation model developed in this study comprises three sequential modules. The first module is for estimating the demand for the PV system under the subsidy and the carbon taxation policy, the second is the module for life-cycle inventory analysis based on the modified Input–Output table, and the third is the module for calculating the amount of carbon-dioxide emissions from the final-demand vector of the Input–Output table. Major findings of this study are as follows: (1) The amount of CO₂-emission reduction increases by advertising the PV system with subsidy policy even under the same tax-rate. (2) The CO₂-payback time of the PV system reduces by half if the GDP is assumed not to change after the introduction of carbon taxation.     

Sensory Preconditioning in Spatial Learning Using a Touch Screen Task in Pigeons.

The authors used a touch screen-based visual-search task to investigate spatial integration in pigeons. First, pigeons were presented with a consistent spatial relationship between compound visual landmarks (LMs) A-X and B-Y, separately. Next, pigeons learned to find a hidden goal on the monitor in the presence of LMs A and B. The goal bore a consistent spatial relationship to LM A, but not to LM B. On nonreinforced probe tests, the peak and distribution of responses to LM X suggest that pigeons computed a novel X-goal spatial relationship on the basis of X-A and A-goal spatial vectors. Responses to LM Y, however, revealed no evidence of spatial integration. These results replicate and extend those of A. P. Blaisdell and R. G. Cook (2005) using an open-field task. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Role of alveolar macrophages in initiation and regulation of inflammation in Pseudomonas aeruginosa pneumonia

To evaluate the role of alveolar macrophages (AMs) in acute Pseudomonas aeruginosa pneumonia in mice, AMs were depleted by aerosol inhalation of liposomes containing clodronate disodium. AM-depleted mice were then intratracheally infected with 5 x 10(5) CFU of P. aeruginosa. In addition to monitoring neutrophil recruitment and chemokine releases, lung injury was evaluated soon after infection (8 h) and at a later time (48 h). At 8 h, depletion of AMs reduced neutrophil recruitment, chemokine release, and lung injury. At 48 h, however, depletion of AMs decreased bacterial clearance and resulted in delayed movement of neutrophils from the site of inflammation with aggravated lung injury. With instillation of 5 x 10(7) CFU of bacteria, AM-depleted mice showed low mortality within 24 h of infection but high mortality at a later time, in contrast to non-AM-depleted mice. These results demonstrate that depletion of AMs has beneficial early effects but deleterious late effects on lung injury and survival in cases of P. aeruginosa pneumonia.     

Analysis of slotlines and microstrip lines on anisotropicsubstrates

The propagation characteristics of the dominant mode in slotlines as well as in microstrip lines on anisotropic substrates are studied. The dielectric tensor in the substrate may have nondiagonal elements which represent misalignment, on the substrate surface, between the material coordinate system and the waveguide coordinate system. The analysis is devoted to the slotline and is based on Galerkin's method applied in the spectral domain. Numerical results are presented for a sapphire substrate and a boron nitride substrate. It is found that the coordinate misalignment on the substrate surface has a significant influence on the propagation characteristics of the slotline     

Prevention of hypoxic liver cell necrosis by in vivo human bcl-2 gene transfection

Acute unilateral monosymptomatic optic neuritis (ON) is a common first manifestation of MS if associated with multiple MS-like lesions on brain MRI and oligoclonal IgG bands (OB) in the CSF, whereas ON patients lacking these laboratory abnormalities are considered to have a good prognosis regarding future MS development. Several cytokines involved in immune regulation are upregulated in blood and even more noticeable in CSF in MS. To study a possible relation between cytokine profiles and presence versus absence of MS-like brain MRI lesions and CSF OB, we used in situ hybridization to examine mRNA expression of the proinflammatory interleukin-12 (IL-12), interferon-gamma, and tumor necrosis factor-alpha and the immune response downregulating IL-10, transforming growth factor-beta, and IL-4 in blood and CSF mononuclear cells (MNC) from 59 patients with untreated ON. There were no differences in numbers of MNC in blood or CSF expressing any of the cytokines under study, upon subgrouping the ON patients regarding presence (n = 31) versus absence (n = 28) of MRI lesions, presence (n = 45) versus absence (n = 14) of OB, or duration after onset of ON (<1 month, n = 30, versus >1 month, n = 29). Similarly, no differences were observed for numbers of myelin basic protein-reactive blood MNC expressing any of these cytokines after subgrouping according to these variables. Our findings suggest that the cytokine profile, as examined in this study, is less useful to determine the risk of future development of clinically definite MS in ON patients or as indicator for therapeutic interventions in ON. An upregulation of both pro- and anti-inflammatory cytokines in ON patients seems to be more related to the CNS disease per se, whether limited to the optic nerve or not, than to the inflammatory process characteristic for MS.     

Prevention of galling in forming of deep hole with retreat and advance pulse ram motion on servo press

To prevent galling in backward extrusion of deep holes, an extrusion method utilizing a servo press and a punch having an internal channel for supplying liquid lubricant is proposed. On the servo press, the punch is pushed into the billet in a manner combining pulsed and stepwise modes. The lubricant is sucked into the formed hole through the internal channel during the retreat motion of the punch. Appropriate punch ram motions for preventing galling are determined from the surface observation of the formed hole. The maximum aspect ratio of the hole attained by the proposed method is discussed.