368 research outputs found
Beta-Delayed fission of 230Am
The exotic decay process of β-delayed fission (βDF) has been studied in the neutron-deficient isotope Am230. The Am230 nuclei were produced in the complete fusion reaction Pb207(Al27,4n)Am230 and separated by using the GARIS gas-filled recoil ion separator. A lower limit for the βDF probability PβDF(Am230)>0.30 was deduced, which so far is the highest value among all known βDF nuclei. The systematics of βDF in the region of Am230 will be discussed
Impact of the Specific Mutation in KRAS Codon 12 Mutated Tumors on Treatment Efficacy in Patients with Metastatic Colorectal Cancer Receiving Cetuximab-Based First-Line Therapy: A Pooled Analysis of Three Trials
Purpose: This study investigated the impact of specific mutations in codon 12 of the Kirsten-ras (KRAS) gene on treatment efficacy in patients with metastatic colorectal cancer (mCRC). Patients: Overall, 119 patients bearing a KRAS mutation in codon 12 were evaluated. All patients received cetuximab-based first-line chemotherapy within the Central European Cooperative Oncology Group (CECOG), AIO KRK-0104 or AIO KRK-0306 trials. Results: Patients with KRAS codon 12 mutant mCRC showed a broad range of outcome when treated with cetuximab-based first-line regimens. Patients with tumors bearing a KRAS p.G12D mutation showed a strong trend to a more favorable outcome compared to other mutations (overall survival 23.3 vs. 14-18 months; hazard ratio 0.66, range 0.43-1.03). An interaction model illustrated that KRAS p.G12C was associated with unfavorable outcome when treated with oxaliplatin plus cetuximab. Conclusion: The present analysis suggests that KRAS codon 12 mutation may not represent a homogeneous entity in mCRC when treated with cetuximab-based first-line therapy. Copyright (C) 2012 S. Karger AG, Base
Биомеханические характеристики точностно-целевых ударных движений в спортивном карате
The methods of electrmiography and stabilography are used to determine biomechanic characteristics of target-oriented kick motions in sportive karate. It is shown that highly qualified sportsmen can better maintain equilibrium in main karate combat maneuvers. This shows itself in the smaller amplitude of vibrations of the common center of gravity and in higher quality values of the equilibrium function compared to lower-qualification sportsmen. In addition, masters of sports show the synchronous operation of motor units, their simultaneous participation in a kick motion. The dynamics of main stabilogram and electromiogram characteristics can be used as an indicator of the level of technical training of sportsmen.Методами электромиографии и стабилографии определены биомеханические характеристики точностно-целевых ударных движений в спортивном карате. Показано, что высококвалифицированные спортсмены способны лучше поддерживать равновесие при выполнении основных боевых приемов карате, что проявляется в меньшей амплитуде колебаний общего центра тяжести и больших значениях качества функции равновесия в сравнении с каратистами низкой квалификации. Также у мастеров спорта наблюдается синхронизация работы двигательных единиц, одновременное их вовлечение в выполнение ударного движения. Динамика основных характеристик стабилограммы и электромиограммы может использоваться в качестве индикатора уровня технической подготовленности спортсменов
Large-Scale Sidereal Anisotropy of Galactic Cosmic-Ray Intensity Observed by the Tibet Air Shower Array
We present the large-scale sidereal anisotropy ofgalactic cosmic-ray
intensity in the multi-TeV region observed with the Tibet-IIIair shower array
during the period from 1999 through 2003. The sidereal daily variation of
cosmic rays observed in this experiment shows an excess of relative intensity
around hours local sidereal time, as well as a deficit around 12
hours local sidereal time. While the amplitude of the excess is not significant
when averaged over all declinations, the excess in individual declinaton bands
becomes larger and clearer as the viewing direction moves toward the south. The
maximum phase of the excess intensity changes from 7 at the northern
hemisphere to 4 hours at the equatorial region. We also show that both
the amplitude and the phase of the first harmonic vector of the daily variation
are remarkably independent of primary energy in the multi-TeV region. This is
the first result determining the energy and declination dependences of the full
24-hour profiles of the sidereal daily variation in the multi-TeV region with a
single air shower experiment.Comment: 13 pages, 3 figures, 1 table. Accepted for publication in ApJ
Detailed α-decay study of 180Tl
International audienceA detailed -decay spectroscopy study of has been performed at ISOLDE (CERN). -selective ionization by the Resonance Ionization Laser Ion Source (RILIS) coupled to mass separation provided a high-purity beam of . Fine-structure decays to excited levels in the daughter were identified and an -decay scheme of was constructed based on an analysis of - and -- coincidences. Multipolarities of several -ray transitions deexciting levels in were determined. Based on the analysis of reduced -decay widths, it was found that all decays are hindered, which signifies a change of configuration between the parent and all daughter states
Large enhancement of the sub-barrier fusion probability for a halo nucleus
The fusion-fission cross sections of the He-4 + U-238 and He-6 + U-238 systems have been measured, at Louvain-la-Neuve, for energies around and below the Coulomb barrier, using an array of Si detectors surrounding a UF4 target. The data taken with 4He are in good agreement with previous data and with the coupled channel fusion calculation performed with ECIS. The He-6 data show a regular trend with a large enhancement below the barrier which is attributed to the halo structure of the He-6 nucleus
β-delayed fission and α decay of At196
A nuclear-decay spectroscopy study of the neutron-deficient isotope At196 is reported where an isotopically pure beam was produced using the selective Resonance Ionization Laser Ion Source and On-Line Isotope Mass Separator (CERN). The fine-structure α decay of At196 allowed the low-energy excited states in the daughter nucleus Bi192 to be investigated. A β-delayed fission study of At196 was also performed. A mixture of symmetric and asymmetric fission-fragment mass distributions of the daughter isotope Po196 (populated by β decay of At196) was deduced based on the measured fission-fragment energies. A βDF probability PβDF(At196)=9(1)×10−5 was determined
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