Development and a SEU Test of a TDC LSI for the ATLAS Muon Detector

A new TDC LSI (AMT-2) for the ATLAS Muon detector has been developed. The AMT-2 chip is a successor of the previous prototype chip (AMT-1). The design of the chip was polished up for aiming mass production of 20,000 chips in year 2002. Especially, power consumption of the chip was reduced to less than half of the previous chip by introducing newly developed LVDS receivers. The AMT-2 was processed in a 0.3 mu m CMOS Gate-Array technology. It achieved 300 ps timing resolution and includes several data buffers, trigger matching circuit, JTAG interface and so on. First SEU test by using a proton beam was recently performed. Although the test results are very preliminary at present stage, we get very low SEU rate safely used in ATLAS environment. (7 refs)

Performance and Irradiation Tests of the 0.3μ\mum CMOS TDC for the ATLAS MDT

ATLAS Muon TDC test-element group chip (AMTTEG) was developed and tested to confirm the performance of critical circuits of the TDC and measure radiation tolerance of the process. The chip was fabricated in a 0.3 mm CMOS Gate-Array technology. Measurements of critical elements of the chip such as the PLL, and data buffering circuits demonstrated adequate performance. The effect of gamma-ray irradiation, using a Co60 source, and neutron irradiation, using PROSPERO reactor in France, were also examined. The test results revealed radiation tolerance adequate for the operation of the circuits in the environment of the ATLAS MDT

Efficacy of capillary pattern type IIIA/IIIB by magnifying narrow band imaging for estimating depth of invasion of early colorectal neoplasms

<p>Abstract</p> <p>Background</p> <p>Capillary patterns (CP) observed by magnifying Narrow Band Imaging (NBI) are useful for differentiating non-adenomatous from adenomatous colorectal polyps. However, there are few studies concerning the effectiveness of magnifying NBI for determining the depth of invasion in early colorectal neoplasms. We aimed to determine whether CP type IIIA/IIIB identified by magnifying NBI is effective for estimating the depth of invasion in early colorectal neoplasms.</p> <p>Methods</p> <p>A series of 127 consecutive patients with 130 colorectal lesions were evaluated from October 2005 to October 2007 at the National Cancer Center Hospital East, Chiba, Japan. Lesions were classified as CP type IIIA or type IIIB according to the NBI CP classification. Lesions were histopathologically evaluated. Inter and intraobserver variabilities were assessed by three colonoscopists experienced in NBI.</p> <p>Results</p> <p>There were 15 adenomas, 66 intramucosal cancers (pM) and 49 submucosal cancers (pSM): 16 pSM superficial (pSM1) and 33 pSM deep cancers (pSM2-3). Among lesions diagnosed as CP IIIA 86 out of 91 (94.5%) were adenomas, pM-ca, or pSM1; among lesions diagnosed as CP IIIB 28 out of 39 (72%) were pSM2-3. Sensitivity, specificity and diagnostic accuracy of the CP type III for differentiating pM-ca or pSM1 (<1000 μm) from pSM2-3 (≥1000 μm) were 84.8%, 88.7 % and 87.7%, respectively. Interobserver variability: κ = 0.68, 0.67, 0.72. Intraobserver agreement: κ = 0.79, 0.76, 0.75</p> <p>Conclusion</p> <p>Identification of CP type IIIA/IIIB by magnifying NBI is useful for estimating the depth of invasion of early colorectal neoplasms.</p

Structure and physical properties of Na4C60 under ambient and high pressures

The structure and physical properties of two-dimensional polymeric Na4C60 (body-centered monoclinic, space group I2/m) are studied in a wide temperature region from 12 to 300 K at 1 bar, and in a pressure region up to 53 kbar at 300 K. The temperature dependence of lattice constants suggests a structural anomaly below 100 K where the variation of spin susceptibility is observed from electron spin resonance. The thermal expansion of the unit-cell volume V is smaller than that of monomeric Rb3C60 and K3C60. The compressibility of c is larger than that of a and b, which can be well explained by the repulsion between Na ions. The compressibility of the center-to-center distance in the (10(1) over bar) plane is similar to1/3 times smaller that that in the (101) plane, which can be well explained by the formation of the polymer chains. Further, a possibility of a three-dimensional polymerization is discussed on the basis of the pressure dependence of C-60. . .C-60 distances.</p

Metal-insulator transition at 50 K in Na2C60

Temperature dependence of electron spin resonance in Na2C60 was studied in a temperature range from 2 to 350 K. It was shown that Na2C60 was metallic above 50 K and had a metal-insulator transition at 50 K. The center frequency for the Hg(2) Raman mode in Na2C60 at 298 K was close to those in the metallic Rb3C60, K3C60, and Cs3C60, while the linewidth was close to that in the metallic but nonsuperconducting Cs3C60. The Hg(2) mode showed a large blueshift and narrowing at 50 K. The center frequency and the linewidth in the low-temperature region from 50 K were almost the same as those in the insulating C-60 and Rb6C60, which showed the metal-insulator transition at 50 K in Na2C60. The origin of this metal-insulator transition was discussed in terms of the electron-phonon interaction (Jahn-Teller effect) and the electron-electron interaction (Mott-Hubbard picture). [S0163-1829(99)04123-5].</p

Simple and Rapid Enzymatic Method for the Synthesis of Single-Strand Oligonucleotides Containing Trifluorothymidine

To investigate the mechanism of trifluorothymidine (TFT)-induced DNA damage, we developed an enzymatic method for the synthesis of single-strand oligonucleotides containing TFT-monophosphate residues. Sixteen-mer oligonucleotides and 14-mer 5′-phosphorylated oligonucleotides were annealed to the template of 25-mer, so as to empty one nucleotide site. TFT-triphosphate was incorporated into the site by DNA polymerase and then ligated to 5′-phosphorylated oligonucleotides by DNA ligase. The synthesized 31-mer oligonucleotides containing TFT residues were isolated from the 25-mer complementary template by denaturing polyacrylamide electrophoresis. Using these single-strand oligonucleotides containing TFT residues, the cleavage of TFT residues from DNA, using mismatch uracil-DNA glycosylase (MUG) of E.coli origin, was compared with that of 5-fluorouracil (5FU) and 5-bromodeoxyuridine (BrdU). The TFT/A pair was not cleaved by MUG, while the other pairs, namely, 5FU/A, 5FU/G, BrdU/A, BrdU/G, and TFT/G, were easily cleaved from each synthesized DNA. Thus, this method is useful for obtaining some site-specifically modified oligonucleotides

Probing the DeltaNN component of 3He

The 3He(gamma,pi^+/- p) reactions were measured simultaneously over a tagged photon energy range of 800<E_gamma<1120 MeV, well above the Delta resonance region. An analysis was performed to kinematically isolate Delta knockout events from conventional Delta photoproduction events, and a statistically significant excess of pi+p events was identified, consistent with Delta++ knockout. Two methods were used to estimate the DeltaNN probability in the 3He ground state, corresponding to the observed knockout cross section. The first gave a lower probability limit of 1.5+/-0.6+/-0.5%; the second yielded an upper limit of about 2.6%.Comment: 14 page

Mechanism of trifluorothymidine potentiation of oxaliplatin-induced cytotoxicity to colorectal cancer cells

Oxaliplatin (OHP) is an anticancer agent that acts by formation of Platinum-DNA (Pt-DNA) adducts resulting in DNA-strand breaks and is used for the treatment of colorectal cancer. The pyrimidine analog trifluorothymidine (TFT) forms together with a thymidine phosphorylase inhibitor (TPI) the anticancer drug formulation TAS-102, in which TPI enhances the bioavailability of TFT in vivo. In this in vitro study the combined cytotoxic effects of OHP with TFT were investigated in human colorectal cancer cells as a model for TAS-102 combinations. In a panel of five colon cancer cell lines (WiDr, H630, Colo320, SNU-C4 and SW1116) we evaluated the OHP-TFT drug combinations using the multiple drug–effect analysis with CalcuSyn software, in which the combination index (CI) indicates synergism (CI<0.9), additivity (CI=0.9–1.1) or antagonism (CI>1.1). Drug target analysis was used for WiDr, H630 and SW1116 to investigate whether there was an increase in Pt-DNA adduct formation, DNA damage induction, cell cycle delay and apoptosis. Trifluorothymidine combined with OHP resulted in synergism for all cell lines (all CI<0.9). This was irrespective of schedule in which either one of the drugs was kept at a constant concentration (using variable drug ratio) or when the two drugs were added in a 1 : 1 IC50-based molar ratio. Synergism could be increased for WiDr using sequential drug treatment schedules. Trifluorothymidine increased Pt-DNA adduct formation significantly in H630 and SW1116 (14.4 and 99.1%, respectively; P<0.05). Platinum-DNA adducts were retained best in SW1116 in the presence of TFT. More DNA-strand breaks were induced in SW1116 and the combination increased DNA damage induction (>20%) compared with OHP alone. Exposure to the drugs induced a clear cell-cycle S-phase arrest, but was dose schedule and cell line dependent. Trifluorothymidine (TFT) and OHP both induced apoptosis, which increased significantly for WiDr and SW1116 after TFT–OHP exposure (18.8 and 20.6% respectively; P<0.05). The basal protein levels of ERCC1 DNA repair enzyme were not related to the DNA damage that was induced in the cell lines. In conclusion, the combination of TFT with the DNA synthesis inhibitor OHP induces synergism in colorectal cancer cells, but is dependent on the dose and treatment schedule used