281 research outputs found
Altered p16INK4 and RB1 Expressions Are Associated with Poor Prognosis in Patients with Nonsmall Cell Lung Cancer
p16INK4 and RB1 are two potent cell cycle regulators to control the G1/S transition by interacting with CDK4/6, E2F, and D-type cyclins, respectively. Depending on the tumour type, genetic alterations resulting in the functional inactivation have frequently been reported in both genes. By contrast, much less is known regarding the overexpression of these proteins in the tumor cells. In this study, expressions of p16INK4 RB1, and CDKN2A copy number variances (CNV) in the tumor cells were assessed by immunohistochemistry and fluorescence in situ hybridization (FISH), respectively, in 73 nonsmall cell lung cancer (NSCLC) with known 5-year survivals. The histologic type (P = 0.01), p16INK4 (P = 0.004), and RB1 (P < 0.001) were predictive of survivals. The CDKN2A CNV (P < 0.05) was also significant when compared to those cases without CNV. Therefore, among the molecular genetic prognostic factors, expressions of RB1 and p16INK4 in the tumor cells were the most strongly predictive of adverse outcomes in stage I and II nonsquamous NSCLC
Search for an Annual Modulation in a P-type Point Contact Germanium Dark Matter Detector
Fifteen months of cumulative CoGeNT data are examined for indications of an
annual modulation, a predicted signature of Weakly Interacting Massive Particle
(WIMP) interactions. Presently available data support the presence of a
modulated component of unknown origin, with parameters prima facie compatible
with a galactic halo composed of light-mass WIMPs. Unoptimized estimators yield
a statistical significance for a modulation of ~2.8 sigma, limited by the short
exposure.Comment: Published version, slightly expanded discussion of ROI uncertainties,
one reference adde
The Majorana experiment: an ultra-low background search for neutrinoless double-beta decay
The observation of neutrinoless double-beta decay would resolve the Majorana
nature of the neutrino and could provide information on the absolute scale of
the neutrino mass. The initial phase of the Majorana experiment, known as the
Demonstrator, will house 40 kg of Ge in an ultra-low background shielded
environment at the 4850' level of the Sanford Underground Laboratory in Lead,
SD. The objective of the Demonstrator is to determine whether a future 1-tonne
experiment can achieve a background goal of one count per tonne-year in a
narrow region of interest around the 76Ge neutrinoless double-beta decay peak.Comment: Presentation for the Rutherford Centennial Conference on Nuclear
Physic
The MAJORANA DEMONSTRATOR: A Search for Neutrinoless Double-beta Decay of Germanium-76
The observation of neutrinoless double-beta decay would determine whether the
neutrino is a Majorana particle and provide information on the absolute scale
of neutrino mass. The MAJORANA Collaboration is constructing the DEMONSTRATOR,
an array of germanium detectors, to search for neutrinoless double-beta decay
of 76-Ge. The DEMONSTRATOR will contain 40 kg of germanium; up to 30 kg will be
enriched to 86% in 76-Ge. The DEMONSTRATOR will be deployed deep underground in
an ultra-low-background shielded environment. Operation of the DEMONSTRATOR
aims to determine whether a future tonne-scale germanium experiment can achieve
a background goal of one count per tonne-year in a 4-keV region of interest
around the 76-Ge neutrinoless double-beta decay Q-value of 2039 keV.Comment: Submitted to AIP Conference Proceedings, 19th Particles & Nuclei
International Conference (PANIC 2011), Massachusetts Institute of Technology,
Cambridge, MA, USA, July 24-29, 2011; 3 pages, 1 figur
Properties of stellar generations in Globular Clusters and relations with global parameters
ABRIDGED) We revise the formation of Galactic GCs by adding the detailed
chemical composition of their different stellar generations (from 1200 giants
in 19 GCs) to their global parameters. We propose to identify as GCs those
showing the Na-O anticorrelation, and we classify the GCs according to
kinematics and location in the Galaxy in disk/bulge, inner, and outer halo. We
find that the LF of GCs is fairly independent of their population, suggesting
that it is imprinted by the formation mechanism, and only marginally affected
by the ensuing evolution. We show that a large fraction of the primordial
population should have been lost by the proto-GCs. The extremely low Al
abundances found for the primordial population of massive GCs indicate a very
fast enrichment process before the formation of the primordial population. We
suggest a scenario for the formation of GCs including at least 3 main phases:
i) the formation of a precursor population (likely due to the interaction of
cosmological structures similar to those leading to dwarf spheroidals, but
residing at smaller Rgc, with the early Galaxy or with other structures), ii)
which triggers a large episode of star formation (the primordial population),
and iii) the formation of the current GC, mainly within a cooling flow formed
by the slow winds of a fraction of the primordial population. The precursor
population is very effective in raising the metal content in massive and/or
metal poor (mainly halo) clusters, while its role is minor in small and/or
metal rich (mainly disk) ones. Finally, we use PCA and multivariate relations
to study the phase of metal-enrichment from 1st to 2nd generation. Most of the
chemical signatures of GCs may be ascribed to a few parameters, the most
important being [Fe/H], mass, and age of the cluster, with the location within
the Galaxy also playing some role.Comment: 24 pages (+2 pages of bibliography and 5 of Appendix), 19 figures,
accepted for publication on Astronomy and Astrophysic
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