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Tadashi Iwai, Manabu Hoshi, Naoto Oebisu, Kumi Orita, Akiyoshi Shimatani, Naoki Takada, Hiroaki Nakamura Department of Orthopedic Surgery, Osaka City University Graduate School of Medicine, Osaka, 545-8585, JapanCorrespondence: Tadashi IwaiDepartment of Orthopedic Surgery, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-Machi, Abeno-Ku, Osaka, 545-8585, JapanTel +81-6-6645-3851Fax +81-6-6646-6260Email qq329xpd@opal.ocn.ne.jpPurpose: We aimed to determine if finite element analysis (FEA) provides useful thresholds for bone biopsy practice patterns.Methods: The femoral head compression test was performed on rabbit femurs, using FEA to identify the part of the bone that preferentially fractures (n=15/group). Four types of rectangular biopsy holes were made using finite element (FE) models. These models were divided into control (no defect), defect 1 (10% width), defect 2 (20% width), defect 3 (30% width), and defect 4 (40% width) groups (n=15 each). Three types of rectangular biopsy holes (defect A, 27% length; defect B, 40% length; defect C, 53% length) were also made using FE models (n=15 each). The load to failure was then predicted using FEA.Results: Almost all femurs with no defect were fractured at the femoral shaft in both the femoral head compression test and FEA. The experimental load to failure in intact femurs was predicted well by the FE models (R2=0.74, p< 0.001). There was also a strong linear correlation of stiffness between compression test in femurs with no defect and the FEA (R2=0.68, p< 0.001). Therefore, the femoral shaft was targeted for FEA. The median predicted loads by FEA were significantly higher for defect 1 than for the other types when testing the widths of the rectangular defects, but there were no significant differences among the three types when testing for defect length.Conclusion: The FEA results correlated well with those of the femoral head compression test. A width < 10% of the circumference length in bone biopsy holes helps minimize bone strength reduction using FEA. It may be useful for orthopedic doctors to perform FEA to avoid pathological fractures after bone tumor biopsy.Keywords: femur, orthopedics, bone tumor biopsy, New Zealand white rabbits, finite element analysis

Abstract: Black spot disease, which is caused by the Japanese pear pathotype of Alternaria alternata (Fr.) Keissler, is one of the most harmful diseases in Japanese pear cultivation. We identified [...]

The ATLAS level-1 muon endcap trigger system is divided into three parts; one off-detector part and two on-detector parts. Application specific ICs (ASICs) and anti-fuse Field Programmable Gate Array (FPGAs) are actively used in the on-detector parts. A Low-Voltage Data Signaling (LVDS) serial link is used for the data transfer between the two on-detector parts (15 m apart) and G-Link (Hewlett-Packard 1.4 Gbaud high speed data link) with optical transmission (90 m) is used from one of the on-detector parts to the off-detector part. These components will be exposed to a radiation of approximately 200 Gy (including safety factors) for ten years corresponding to a total ionizing dose (TID) and a hadron fluence of 2 x [10.sup.10] hadrons/[cm.sup.2]. We have investigated systematically the radiation susceptibility to both the total ionizing dose and the single event effects for ASIC, FPGA, and Commercial Off The Shelf (COTS) serializer and deserializer chipsets for two types of LVDS serial link and one G-Link type. In this documentation we report the result of the irradiation tests for these devices and discuss their validity in the ATLAS system. Index Terms--Application specific integrated circuits, optical fiber radiation effects, semiconductor device radiation effects.

An investigation on the influence of the fluorocarbon gas (C5F8, C4F8, and CF4 molecules) flux onto SiO2 etching reaction is done in a beam apparatus. The findings suggest a significant contribution of direct SiO2 etching by fluorocarbon molecules in practical etching reactors, especially in case of the C5F8 molecules.

A new study investigates the optical and structural properties of distyrylbenzene derivative thin films.

Three different factors influence the width of the spectral output from the amplifier of an optically pumped high-power D2O laser system. Narrow spectral outputs of about 10 megahertz width are obtained when the D20 gas pressure is between 6 and 7 Torricelli, the intensity of the laser beam is more than 50 Weber per square centimeter and the oscillation frequency is between 15 and 35 megahertz. The D2O laser system is operated using a configuration with an oscillator-amplifier.