Approximate natural vibration analysis of rectangular plates with openings using assumed mode method

ABSTRACTNatural vibration analysis of plates with openings of different shape represents an important issue in naval architecture and ocean engineering applications. In this paper, a procedure for vibration analysis of plates with openings and arbitrary edge constraints is presented. It is based on the assumed mode method, where natural frequencies and modes are determined by solving an eigenvalue problem of a multi-degree-of-freedom system matrix equation derived by using Lagrange's equations of motion. The presented solution represents an extension of a procedure for natural vibration analysis of rectangular plates without openings, which has been recently presented in the literature. The effect of an opening is taken into account in an intuitive way, i.e. by subtracting its energy from the total plate energy without opening. Illustrative numerical examples include dynamic analysis of rectangular plates with rectangular, elliptic, circular as well as oval openings with various plate thicknesses and different combinations of boundary conditions. The results are compared with those obtained by the finite element method (FEM) as well as those available in the relevant literature, and very good agreement is achieved

The effects of the sliver carp (Hypophthalmichthys molitrix) predation on the extracellular enzymatic activities

Article信州大学理学部附属諏訪臨湖実験所報告 9: 77-85(1995)departmental bulletin pape

The distribution of attached bacteria on cellulose film and cellulose degradation rates in Lake Soyang, Korea.

Article信州大学理学部附属諏訪臨湖実験所報告 9: 69-75(1995)departmental bulletin pape

Concurrence of Stevens-Johnson Syndrome and Bilateral Parotitis after Minocycline Therapy

Minocycline is an antibiotic of tetracycline derivatives that is commonly used in the treatment of moderate to severe acne vulgaris. It has been reported to cause rare adverse events from mild cutaneous eruption to severe forms including drug-induced lupus, serum sickness-like reaction, and hypersensitivity reactions, etc. The risks of adverse events attributed to minocycline have not been ascertained reliably and there are concerns about the safety of minocycline which could possibly result in life-threatening events such as the Stevens-Johnson syndrome. Here we demonstrate an unusual case of Stevens-Johnson syndrome in conjunction with bilateral parotitis after the intake of minocycline in a Korean boy suggesting discreet use of the drug

The origin of proinflammatory cytokines in patients with idiopathic dilated cardiomyopathy.

Proinflammatory cytokines and their receptors are increased in the peripheral blood of patients with heart failure. We measured cytokines and their receptors in systemic artery (SA), coronary sinus (CS) and infra-renal inferior vena cava (IVC), in order to investigate their origin and influential factors. Thirty patients with idiopathic dilated cardiomyopathy were performed echocardiography at admission, and right heart catheterization after stabilization. Blood was drawn from 3 sites for measurement of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and soluble tumor necrosis factor-alpha receptor (sTNFR) I, II. TNF-alpha at CS (3.25 +/- 0.34 pg/mL) was higher than those of SA (1.81 +/- 0.39 pg/mL) and IVC (1.88 +/- 0.38 pg/mL, p<0.05). IL-6 at CS (18.3 +/- 3.8 pg/mL) was higher than that of SA (5.8 +/- 1.2 pg/mL, p<0.01). The levels of sTNFR I, II showed increasing tendency in sequence of SA, IVC and CS. TNF-alpha and sTNFR I, II from all sites were proportional to worsening of functional classes at admission (p<0.05). E/Ea by Doppler study at admission, which reflects left ventricular end-diastolic pressure (LVEDP) was positively correlated with TNF-alpha from SA (R=0.71, p<0.01), CS (R=0.52, p<0.05) and IVC (R=0.46, p<0.05). Thus, elevated LVEDP during decompensation might cause cytokine release from myocardium in patients with idiopathic dilated cardiomyopathy

Autism-like behavior caused by deletion of vaccinia-related kinase 3 is improved by TrkB stimulation

Vaccinia-related kinases (VRKs) are multifaceted serine/threonine kinases that play essential roles in various aspects of cell signaling, cell cycle progression, apoptosis, and neuronal development and differentiation. However, the neuronal function of VRK3 is still unknown despite its etiological potential in human autism spectrum disorder (ASD). Here, we report that VRK3-deficient mice exhibit typical symptoms of autism-like behavior, including hyperactivity, stereotyped behaviors, reduced social interaction, and impaired context-dependent spatial memory. A significant decrease in dendritic spine number and arborization were identified in the hippocampus CA1 of VRK3-deficient mice. These mice also exhibited a reduced rectification of AMPA receptor-mediated current and changes in expression of synaptic and signaling proteins, including tyrosine receptor kinase B (TrkB), Arc, and CaMKII alpha. Notably, TrkB stimulation with 7,8-dihydroxyflavone reversed the altered synaptic structure and function and successfully restored autism-like behavior in VRK3-deficient mice. These results reveal that VRK3 plays a critical role in neurodevelopmental disorders and suggest a potential therapeutic strategy for ASD.112Ysciescopu

New microbial ecosystem created by artificak floating island

To scrutinize the microbial ecosystem and processing of water quality improvement under the artificial floating island, water quality parameteres, bacterial numbers and extracellular enzyme activities were measured biweekly flom 3, November 2001 to 20,April 2002 in Lake Paldang, Korea. Most of the mean encironmental parameters were not different from artificially floating island (AFI) site and control site. But,zooplankton numbers were about 100 times higher at AFI site than those of control site, even though the chlorophyll α concentrations were not so different. During winter, the rations of respiratory active bacteria to total bacterial number were two fold higher and enzyme activities of β-glucosidase and phosphatase were extremely higher at AFI site than those of contrl site. With these high densities of zooplankton, active bacteria and high rates of degradation under the AFI, the organic materials are eliminated at inside of lake with newly created ecosystem.Article信州大学山地水環境教育研究センター研究報告 2: 5-9(2004)departmental bulletin pape