The existence of tumor-suppressor genes was originally demonstrated by functional complementation through whole-cell and microcell fusion. Transfer of chromosome 11 into a human non-small-cell lung ...cancer (NSCLC) cell line, A549, suppresses tumorigenicity. Loss of heterozygosity (LOH) on the long arm of chromosome 11 has been reported in NSCLC and other cancers. Several independent studies indicate that multiple tumor-suppressor genes are found in this region, including the gene PPP2R1B at 11q23-24 (ref. 7). Linkage studies of NSCLC are precluded because no hereditary forms are known. We previously identified a region of 700 kb on 11q23.2 that completely suppresses tumorigenicity of A549 human NSCLC cells. Most of this tumor-suppressor activity localizes to a 100-kb segment by functional complementation. Here we report that this region contains a single confirmed gene, TSLC1, whose expression is reduced or absent in A549 and several other NSCLC, hepatocellular carcinoma (HCC) and pancreatic cancer (PaC) cell lines. TSLC1 expression or suppression is correlated with promoter methylation state in these cell lines. Restoration of TSLC1 expression to normal or higher levels suppresses tumor formation by A549 cells in nude mice. Only 2 inactivating mutations of TSLC1 were discovered in 161 tumors and tumor cell lines, both among the 20 primary tumors with LOH for 11q23.2. Promoter methylation was observed in 15 of the other 18 primary NSCLC, HCC and PaC tumors with LOH for 11q23.2. Thus, attenuation of TSLC1 expression occurred in 85% of primary tumors with LOH. Hypermethylation of the TSLC1 promoter would seem to represent the 'second hit' in NSCLC with LOH.
The COSINE-100 liquid scintillator veto system Adhikari, G.; Barbosa de Souza, E.; Carlin, N. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2021, Volume:
1006
Journal Article
Peer reviewed
Open access
This paper describes the liquid scintillator veto system for the COSINE-100 dark matter experiment and its performance. The COSINE-100 detector consists of eight NaI(Tl) crystals immersed in 2200 L ...of linear alkylbenzene-based liquid scintillator. The liquid scintillator tags between 65 and 75% of the internal 40K background in the 2–6 keV energy region. We also describe the background model for the liquid scintillator, which is primarily used to assess its energy calibration and threshold.
The CUORE experiment is a ton-scale array of
TeO
2
cryogenic bolometers located at the underground Laboratori Nazionali del Gran Sasso of Istituto Nazionale di Fisica Nucleare (INFN), in Italy. The ...CUORE detector consists of 988 crystals operated as source and detector at a base temperature of
∼
10
mK. Such cryogenic temperature is reached and maintained by means of a custom built cryogen-free dilution cryostat, designed with the aim of minimizing the vibrational noise and the environmental radioactivity. The primary goal of CUORE is the search for neutrinoless double beta decay of
130
Te
, but thanks to its large target mass and ultra-low background it is suitable for the study of other rare processes as well, such as the neutrinoless double beta decay of
128
Te
. This tellurium isotope is an attractive candidate for the search of this process, due to its high natural isotopic abundance of 31.75%. The transition energy at (866.7 ± 0.7) keV lies in a highly populated region of the energy spectrum, dominated by the contribution of the two-neutrino double beta decay of
130
Te
. As the first ton-scale infrastructure operating cryogenic
TeO
2
bolometers in stable conditions, CUORE is able to achieve a factor
>
10
higher sensitivity to the neutrinoless double beta decay of this isotope with respect to past direct experiments.
The CUORE experiment, a ton-scale cryogenic bolometer array, recently began operation at the Laboratori Nazionali del Gran Sasso in Italy. The array represents a significant advancement in this ...technology, and in this work we apply it for the first time to a high-sensitivity search for a lepton-number-violating process: ^{130}Te neutrinoless double-beta decay. Examining a total TeO_{2} exposure of 86.3 kg yr, characterized by an effective energy resolution of (7.7±0.5) keV FWHM and a background in the region of interest of (0.014±0.002) counts/(keV kg yr), we find no evidence for neutrinoless double-beta decay. Including systematic uncertainties, we place a lower limit on the decay half-life of T_{1/2}^{0ν}(^{130}Te)>1.3×10^{25} yr (90% C.L.); the median statistical sensitivity of this search is 7.0×10^{24} yr. Combining this result with those of two earlier experiments, Cuoricino and CUORE-0, we find T_{1/2}^{0ν}(^{130}Te)>1.5×10^{25} yr (90% C.L.), which is the most stringent limit to date on this decay. Interpreting this result as a limit on the effective Majorana neutrino mass, we find m_{ββ}<(110-520) meV, where the range reflects the nuclear matrix element estimates employed.
The thermal and electromagnetic loads related to disruptions in ITER are substantial and require careful design of tokamak components to ensure they reach the projected lifetime and to ensure that ...safety relevant components fulfil their function for the worst foreseen scenarios. The disruption load specifications are the basis for the design process of components like the full-W divertor, the blanket modules and the vacuum vessel and will set the boundary conditions for ITER operations. This paper will give a brief overview on the disruption loads and mitigation strategies for ITER and will discuss the physics basis which is continuously refined through the current disruption R&D programs.
COSINE-100 is a direct detection dark matter search experiment that uses a 106 kg array of eight NaI(Tl) crystals that are kept underground at the Yangyang Underground Laboratory to avoid cosmogenic ...activation of radioisotopes by cosmic rays. Even though the cosmogenic activity is declining with time, there are still significant background rates from the remnant nuclides. In this paper, we report measurements of cosmogenic isotope contaminations with less than one year half-lives that are based on extrapolations of the time dependent activities of their characteristic energy peaks to activity rates at the time the crystals were deployed underground. For longer-lived 109Cd (T1/2=1.27 y) and 22Na (T1/2=2.6 y), we investigate time correlations and coincidence events due to several emissions. The inferred sea-level production rates are compared with calculations based on the ACTIVIA and MENDL-2 model calculations and experimental data. The results from different approaches are in reasonable agreement with each other. For 3H, which has a long, 12.3 year half-life, we evaluated the activity levels and the exposure times that are in reasonable agreement with the time period estimated for each crystal’s exposure.
We search for energetic electron recoil signals induced by boosted dark matter (BDM) from the galactic center using the COSINE-100 array of NaI(Tl) crystal detectors at the Yangyang Underground ...Laboratory. The signal would be an excess of events with energies above 4 MeV over the well-understood background. Because no excess of events are observed in a 97.7 kg·yr exposure, we set limits on BDM interactions under a variety of hypotheses. Notably, we explored the dark photon parameter space, leading to competitive limits compared to direct dark photon search experiments, particularly for dark photon masses below 4 MeV and considering the invisible decay mode. Furthermore, by comparing our results with a previous BDM search conducted by the Super-Kamionkande experiment, we found that the COSINE-100 detector has advantages in searching for low-mass dark matter. This analysis demonstrates the potential of the COSINE-100 detector to search for MeV electron recoil signals produced by the dark sector particle interactions.
The projected background for the CUORE experiment Alduino, C.; Avignone, F. T.; Azzolini, O. ...
The European physical journal. C, Particles and fields,
08/2017, Volume:
77, Issue:
8
Journal Article
Peer reviewed
Open access
The Cryogenic Underground Observatory for Rare Events (CUORE) is designed to search for neutrinoless double beta decay of
130
Te with an array of 988 TeO
2
bolometers operating at temperatures ...around 10 mK. The experiment is currently being commissioned in Hall A of Laboratori Nazionali del Gran Sasso, Italy. The goal of CUORE is to reach a 90% C.L. exclusion sensitivity on the
130
Te decay half-life of 9
×
10
25
years after 5 years of data taking. The main issue to be addressed to accomplish this aim is the rate of background events in the region of interest, which must not be higher than 10
-
2
counts/keV/kg/year. We developed a detailed Monte Carlo simulation, based on results from a campaign of material screening, radioassays, and bolometric measurements, to evaluate the expected background. This was used over the years to guide the construction strategies of the experiment and we use it here to project a background model for CUORE. In this paper we report the results of our study and our expectations for the background rate in the energy region where the peak signature of neutrinoless double beta decay of
130
Te is expected.
We report the final result of the CUORICINO experiment. Operated between 2003 and 2008, with a total exposure of 19.75 kg*y of Te, CUORICINO was able to set a lower bound on the Te Ovββhalf-life of ...2.8 ×10years at 90% C.L. The limit here reported includes the effects of systematic uncertainties that are examined in detail in the paper. The corresponding upper bound on the neutrino Majorana mass is in the range 300-710 meV, depending on the adopted nuclear matrix element evaluation.
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