Solubility Limits of Α'-SiAION Solid Solutions in the System Si,Al,Y/N,O

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66438/1/j.1151-2916.1991.tb06797.x.pd

Subsolidus phase relationships in part of the system Si, Al, Ca/N, O

Subsolidus phase relationships in the region bounded by Si3N4, SiO2, CaSiO3, 2CaO.Al2O3.SiO2, CaO.Al2O3, Al2O3 and [beta]'-Si2Al4O4N4([beta]60) have been studied. A new quinary phase with composition near to CaO. 1[middle dot]33Al2O3.0[middle dot]67Si2N2O (designated as S-phase) and a complete series of solid solution between S-phase and CaO.2Al2O3 were found. Fourteen compatible tetrahedra, of which five contain S-phase, occur in the region explored. They are as follows: X1-SiO2-anorthite-mullite; X1-anorthite-mullite-Al2O3; X1-anorthite-Al2O3-[beta]60; X1-anorthite-[beta]60-Si3N4; X1-anorthite-Si3N4-Si2N2O; X1-anorthite-Si2N2O-SiO2; anorthite-Si2N2O-SiO2-CaSiO3; anorthite-Si2N2O-CaSiO3-gehlenite; anorthite-Si2N2O-gehlenite-Si3N4; S-anorthite-Al2O3-[beta]60; S-Al2O3-CaO.2Al2O3-gehlenite; S-Al2O3-gehlenite-anorthite; S-gehlenite-anorthite-Si3N4; S-anorthite-Si3N4-[beta]60.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/27507/1/0000551.pd

Subsolidus phase relationships in the systems Re---Al---O---N (Where Re = Rare Earth Elements)

Subsolidus phase relationships in the systems R---Al---O---N (where Re = Ce, Pr, Nd, and Sm) were determined. A family of lanthanum aluminium oxynitrides, ReAl12O18N, with magnetoplumbite structure occurs, where the rare earth elements have large ionic radii ranging from La to Eu. The lattice parameters of these compounds were determined, and the results indicated that all these compounds have nearly the same value of a = 5.564 A, C = 22.00 A, and c/a = 3.96 A.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/29008/1/0000037.pd

Compound formation and melting behavior in theAB compound and rare earth oxide systems

Compound formation in the systems of the covalent compounds BeO, AlN, and SiC withR2O3(rare earth oxides) is described. Tentative phase diagrams of the AlNNd2O3 and AlNEu2O3 systems are presented.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/28688/1/0000507.pd

Whole pelvic helical tomotherapy for locally advanced cervical cancer: technical implementation of IMRT with helical tomothearapy

<p>Abstract</p> <p>Background</p> <p>To review the experience and to evaluate the treatment plan of using helical tomotherapy (HT) for the treatment of cervical cancer.</p> <p>Methods</p> <p>Between November 1st, 2006 and May 31, 2009, 10 cervical cancer patients histologically confirmed were enrolled. All of the patients received definitive concurrent chemoradiation (CCRT) with whole pelvic HT (WPHT) followed by brachytherapy. During WPHT, all patients were treated with cisplatin, 40 mg/m²intravenously weekly. Toxicity of treatment was scored according to the Common Terminology Criteria for Adverse Events v3.0 (CTCAE v3.0).</p> <p>Results</p> <p>The mean survival was 25 months (range, 3 to 27 months). The actuarial overall survival, disease-free survival, locoregional control and distant metastasis-free rates at 2 years were 67%, 77%, 90% and 88%, respectively. The average of uniformity index and conformal index was 1.06 and 1.19, respectively. One grade 3 of acute toxicity for diarrhea, thrombocytopenia and three grade 3 leucopenia were noted during CCRT. Only one grade 3 of subacute toxicity for thrombocytopenia was noted. There were no grade 3 or 4 subacute toxicities of anemia, leucopenia, genitourinary or gastrointestinal effects. Compared with conventional whole pelvic radiation therapy (WPRT), WPHT decreases the mean dose to rectum, bladder and intestines successfully.</p> <p>Conclusion</p> <p>HT provides feasible clinical outcomes in locally advanced cervical cancer patients. Long-term follow-up and enroll more locally advanced cervical carcinoma patients by limiting bone marrow radiation dose with WPHT technique is warranted.</p

Twisting of the DNA-binding surface by a β-strand-bearing proline modulates DNA gyrase activity

DNA gyrase is the only topoisomerase capable of introducing (−) supercoils into relaxed DNA. The C-terminal domain of the gyrase A subunit (GyrA-CTD) and the presence of a gyrase-specific ‘GyrA-box’ motif within this domain are essential for this unique (−) supercoiling activity by allowing gyrase to wrap DNA around itself. Here we report the crystal structure of Xanthomonas campestris GyrA-CTD and provide the first view of a canonical GyrA-box motif. This structure resembles the GyrA-box-disordered Escherichia coli GyrA-CTD, both adopting a non-planar β-pinwheel fold composed of six seemingly spirally arranged β-sheet blades. Interestingly, structural analysis revealed that the non-planar architecture mainly stems from the tilted packing seen between blades 1 and 2, with the packing geometry likely being defined by a conserved and unusual β-strand-bearing proline. Consequently, the GyrA-box-containing blade 1 is placed at an angled spatial position relative to the other DNA-binding blades, and an abrupt bend is introduced into the otherwise flat DNA-binding surface. Mutagenesis studies support that the proline-induced structural twist contributes directly to gyrase’s (−) supercoiling activity. To our knowledge, this is the first demonstration that a β-strand-bearing proline may impact protein function. Potential relevance of β-strand-bearing proline to disease phenylketonuria is also noted

Iterative joint frequency offset and channel estimation for OFDM systems using first and second order approximation algorithms

[[abstract]]To implement an algorithm for joint estimation of carrier frequency offset (CFO) and channel impulse response (CIR) in orthogonal frequency division multiplexing (OFDM) systems, the maximum-likelihood criterion is commonly adopted. A major difficulty arises from the highly nonlinear nature of the log-likelihood function which renders local extrema or multiple solutions for the CFO and CIR estimators. Use of an approximation method coupled with an adaptive iteration algorithm has been a popular approach to ease problem solving. The approximation used in those existing methods is usually of the first order level. Here, in addition to a new first order approximation method, we also propose a second order approximation method. Further, for the part of the adaptive iteration algorithm, we adopt a new technique which will enable performance improvement. Our first order approximation method is found to outperform the existing ones in terms of estimation accuracies, tracking range, computation complexity, and convergence speed. As expected, our second order approximation method provides an even further improvement at the expense of higher computation complication.[[notice]]補正完畢[[journaltype]]國外[[incitationindex]]SCI[[booktype]]紙本[[booktype]]電子版[[countrycodes]]DE

Design and synthesis of new 2-arylnaphthyridin-4-ones as potent antitumor agents targeting tumorigenic cell lines

To develop new anticancer drug candidates from 2-arylnaphthyridin-4-one (AN), we have designed and synthesized a series of 3′-hydroxy and 6-hydroxy derivatives of AN. The results of cytotoxicity screening indicated that the replacement of the 3′-methoxy moiety on the C-ring phenyl group of AN (6a–e) with 3′-hydroxy (7a–e) made no significant effect on the inhibitory activity against HL-60, Hep3B and NCI-H460 cancer cell lines. On the other hand, replacing the 6-methoxy group on the A-ring of AN (6g–i) with a 6-hydroxy group (7g–i) resulted in reduced inhibitory activity against the above three cancer cell lines. Among the above-mentioned target compounds, 2-(3-hydroxyphenyl)-5-methyl-1,8-naphthyridin-4(1H)-one (7a) demonstrated the greatest potency and the best selectivity toward tumorigenic cancer cell lines. In a 7a preliminary mechanism of action study in Hep3B hepatoma cells, 7a showed the effects on microtubules followed by cell cycle arrest and sequentially led to apoptosis