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Coplanar waveguide (CPW)-fed vertically standing bow-tie antennas for 2.45 GHz ISM band applications for inter-/intraboard wireless communication are presented. The vertical antenna scheme provides wave propagation in the horizontal direction parallel to the substrate, allowing effective in-plane board-to-board communication. The monopole bow-tie antenna is implemented in an air-lifted fashion, resulting in high efficiency, broad bandwidth, and small footprint compared with the conventional surface mounted patch type antenna. The vertical bow-tie antenna with a height of 22.4 mm and a flare angle of 43° shows a 10-dB bandwidth of 20.4%, a footprint of ∼1 mm2, and a height reduction of 33% compared with a cylindrical monopole counterpart. A numerical analysis has been performed between 1 and 4 GHz and the transmission characteristics using two identical antennas have been performed at 2.45 GHz with a network analyzer. The numerical results are in good agreement with experimental data. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 266–269, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23988 [ABSTRACT FROM AUTHOR]

The effect of doping aluminum in the Li[Li0.27Cr0.15Al0.05Mn0.53]O2 layered cathode material has been investigated. The citric acid assisted sot-gel process was used to prepare the cathode material. The electrochemical properties of the cathode material were characterized in coin cells assembled in an argon-filled dry glove box. The Al-doped cathode delivered an initial discharge capacity of 198 mAh/g with a current density of 0.12 mA/cm2. A slight change in the shape of the discharge curve was observed with the substitution of aluminum in Li1.27Cr0.2Mn0.53O2 cathode material. A decreased resistance was observed in the aluminum- doped cathode from the ac impedance spectroscopy. Regarding the state of existence of chromium and manganese ions in the transition metal layer, X-ray photoelectron spectroscopy study results indicated that Mn4+ was reduced to Mn3+ at the end of the discharge. [ABSTRACT FROM AUTHOR]

Objective: We describe the imaging findings of malignant mixed müllerian tumor (MMMT) of the ovary, which have not previously been reported.Materials and Methods: We experienced 13 cases of ovarian MMMT in eight patients. All patients underwent surgical resection and the MMMTs were confirmed pathologically. US (n = 8), CT (n = 8), and MRI (n = 1) examinations were performed before operation. Imaging features were analyzed retrospectively for bilaterality, tumor solidity (cystic or solid), size, and contrast enhancement of the tumor on CT and MRI. Presence of ascites and other evidence of peritoneal seeding, adjacent organ invasion, distant metastasis, and surgical staging were also evaluated.Results: There were bilateral ovarian MMMTs in five patients and unilateral MMMTs in three patients. Two of the MMMTs were multiseptated cystic, and 11 were mixed (solid and cystic). The diameter of the largest dimension was less than 5 cm in one case, 5-10 cm in two cases, and larger than 10 cm in 10 cases. Dense homogeneous contrast enhancement of the solid component was seen in 11 mixed masses. Ascites were found in all patients. Other evidence of peritoneal seeding and direct invasion into adjacent organ such as the uterus or sigmoid colon was seen in five patients each. Pleural metastasis was present in one patient. Surgical stages were FIGO classification IIIb and IV in one patient each, and IIIc in six patients.Conclusion: Ovarian MMMTs usually present as aggressive, bilateral, large, solid and cystic tumors, combined with ascites, frequent peritoneal seeding, and adjacent organ invasion. [ABSTRACT FROM AUTHOR]