804 research outputs found
A Multi Megawatt Cyclotron Complex to Search for CP Violation in the Neutrino Sector
A Multi Megawatt Cyclotron complex able to accelerate H2+ to 800 MeV/amu is
under study. It consists of an injector cyclotron able to accelerate the
injected beam up to 50 MeV/n and of a booster ring made of 8 magnetic sectors
and 8 RF cavities. The magnetic field and the forces on the superconducting
coils are evaluated using the 3-D code OPERA. The injection and extraction
trajectories are evaluated using the well tested codes developed by the MSU
group in the '80s. The advantages to accelerate H2+ are described and
preliminary evaluations on the feasibility and expected problems to build the
injector cyclotron and the ring booster are here presented.Comment: Presentation at Cyclotron'10 conference, Lanzhou, China, Sept 7, 201
Regulation of BALB/c 3T3 fibroblast proliferation by B-myb is accompanied by selective activation of cdc2 and cyclin D1 expression.
Toward the next generation of research into small area effects on health : a synthesis of multilevel investigations published since July 1998.
To map out area effects on health research, this study had the following aims: (1) to inventory multilevel investigations of area effects on self rated health, cardiovascular diseases and risk factors, and mortality among adults; (2) to describe and critically discuss methodological approaches employed and results observed; and (3) to formulate selected recommendations for advancing the study of area effects on health. Overall, 86 studies were inventoried. Although several innovative methodological approaches and analytical designs were found, small areas are most often operationalised using administrative and statistical spatial units. Most studies used indicators of area socioeconomic status derived from censuses, and few provided information on the validity and reliability of measures of exposures. A consistent finding was that a significant portion of the variation in health is associated with area context independently of individual characteristics. Area effects on health, although significant in most studies, often depend on the health outcome studied, the measure of area exposure used, and the spatial scale at which associations are examined
Finite element analysis of horizontal axis wind turbines performance
This paper presents an aeroelastic formulation based on the Finite Element Method
(FEM) to predict the performance of an isolated horizontal axis wind turbine.
Hamiltonâs principle is applied to derive the equations of blade(s) aeroelasticity, based
on a nonlinear beam model coupled with Beddoes-Leishman unsteady sectional aerodynamics.
A devoted fifteen-degrees of freedom finite element, able to accurately model the kinematics and
elastic behavior of rotating blades, is introduced and the spatial discretization of the
aeroelastic equations is carried-out yielding a set of coupled nonlinear ordinary differential
equations that are then solved by a time-marching algorithm. The proposed formulation may be
enhanced to face the analysis of advanced blade shapes, including the presence of the
tower, and represents the first step of an ongoing activity on wind energy based on a FEM
approach. Due to similarities between wind turbine and helicopter rotor blades
aeroelasticity, validation results firstly concern with the aeroelastic response of a helicopter
rotor in hovering. Next, the performance of a wind turbine in terms of blade elastic
response and delivered power are
predicted and compared with available literature data
Finite element analysis of horizontal axis wind turbines performance
This paper presents an aeroelastic formulation based on the Finite Element Method
(FEM) to predict the performance of an isolated horizontal axis wind turbine.
Hamiltonâs principle is applied to derive the equations of blade(s) aeroelasticity, based
on a nonlinear beam model coupled with Beddoes-Leishman unsteady sectional aerodynamics.
A devoted fifteen-degrees of freedom finite element, able to accurately model the kinematics and
elastic behavior of rotating blades, is introduced and the spatial discretization of the
aeroelastic equations is carried-out yielding a set of coupled nonlinear ordinary differential
equations that are then solved by a time-marching algorithm. The proposed formulation may be
enhanced to face the analysis of advanced blade shapes, including the presence of the
tower, and represents the first step of an ongoing activity on wind energy based on a FEM
approach. Due to similarities between wind turbine and helicopter rotor blades
aeroelasticity, validation results firstly concern with the aeroelastic response of a helicopter
rotor in hovering. Next, the performance of a wind turbine in terms of blade elastic
response and delivered power are
predicted and compared with available literature data
Anomalous radio emission from dust in the Helix
A byproduct of experiments designed to map the CMB is the recent detection of
a new component of foreground Galactic emission. The anomalous foreground at ~
10--30 GHz, unexplained by traditional emission mechanisms, correlates with
100um dust emission. We report that in the Helix the emission at 31 GHz and
100um are well correlated, and exhibit similar features on sky images, which
are absent in H\beta. Upper limits on the 250 GHz continuum emission in the
Helix rule out cold grains as candidates for the 31 GHz emission, and provide
spectroscopic evidence for an excess at 31 GHz over bremsstrahlung. We estimate
that the 100um-correlated radio emission, presumably due to dust, accounts for
at least 20% of the 31 GHz emission in the Helix. This result strengthens
previous tentative interpretations of diffuse ISM spectra involving a new dust
emission mechanism at radio frequencies. Very small grains have not been
detected in the Helix, which hampers interpreting the new component in terms of
spinning dust. The observed iron depletion in the Helix favors considering the
identity of this new component to be magnetic dipole emission from hot
ferromagnetic grains. The reduced level of free-free continuum we report also
implies an electronic temperature of Te=4600\pm1200K for the free-free emitting
material, which is significantly lower than the temperature of 9500\pm500K
inferred from collisionally-excited lines (abridged).Comment: Accepted for publication in Ap
Celecoxib inhibits proliferation and survival of chronic myelogeous leukemia (CML) cells via AMPK-dependent regulation of ÎČ-catenin and mTORC1/2.
CML is effectively treated with tyrosine kinase inhibitors (TKIs). However, the efficacy of these drugs is confined to the chronic phase of the disease and development of resistance to TKIs remains a pressing issue. The anti-inflammatory COX2 inhibitor celecoxib has been utilized as anti-tumour drug due to its anti-proliferative activity. However, its effects in hematological malignancies, in particular CML, have not been investigated yet. Thus, we tested biological effects and mechanisms of action of celecoxib in Philadelphia-positive (Ph+) CML and ALL cells.We show here that celecoxib suppresses the growth of Ph+ cell lines by increasing G1-phase and apoptotic cells and reducing S- and G2-phase cells. These effects were independent of COX2 inhibition but required the rapid activation of AMP-activated protein kinase (AMPK) and the consequent inhibition mTORC1 and 2. Treatment with celecoxib also restored GSK3ÎČ function and led to down-regulation of ÎČ-catenin activity through transcriptional and post-translational mechanisms, two effects likely to contribute to Ph+ cell growth suppression by celecoxib.Celecoxib inhibited colony formation of TKI-resistant Ph+ cell lines including those with the T315I BCR-ABL mutation and acted synergistically with imatinib in suppressing colony formation of TKI-sensitive Ph+ cell lines. Finally, it suppressed colony formation of CD34+ cells from CML patients, while sparing most CD34+ progenitors from healthy donors, and induced apoptosis of primary Ph+ ALL cells.Together, these findings indicate that celecoxib may serve as a COX2-independent lead compound to simultaneously target the mTOR and ÎČ-catenin pathways, key players in the resistance of CML stem cells to TKIs
- âŠ