3,751 research outputs found
Cancer mortality in the United Kingdom: projections to the year 2025
The purpose of this study was to project mortality rates in the United Kingdom for the period 2006–2025 for 21 major cancers on the basis of the observed trends in mortality rates during 1971–2005, and to estimate the implication in terms of expected deaths. Age-period-cohort models were applied to official statistics. The projected decrease in age-standardised mortality rates for all cancers from 2003 to 2023 was 17% in men and 16% in women. Future mortality rates were projected to decline for most cancer sites. In men, there were small projected increases in mortality rates from cancers of the oral cavity, oesophagus and melanoma, with a larger projected increase (14% over 20 years) in mortality of liver cancer. In women, the only projected increase (18%) was for corpus uteri. The numbers of deaths will increase for most cancers, with a 30% increase in all cancers projected for men and a 12% increase projected for women. Mortality rates from cancer as a whole have been falling in the United Kingdom since 1990, and this decline was projected to continue into the future as well as the declining rates in both sexes for most cancers. Actual numbers of deaths will increase for most cancers
Multimode optomechanical system in the quantum regime
We realise a simple and robust optomechanical system with a multitude of
long-lived () mechanical modes in a phononic-bandgap shielded membrane
resonator. An optical mode of a compact Fabry-Perot resonator detects these
modes' motion with a measurement rate () that exceeds the
mechanical decoherence rates already at moderate cryogenic temperatures
(). Reaching this quantum regime entails, i.~a., quantum
measurement backaction exceeding thermal forces, and thus detectable
optomechanical quantum correlations. In particular, we observe ponderomotive
squeezing of the output light mediated by a multitude of mechanical resonator
modes, with quantum noise suppression up to -2.4 dB (-3.6 dB if corrected for
detection losses) and bandwidths . The multi-mode
nature of the employed membrane and Fabry-Perot resonators lends itself to
hybrid entanglement schemes involving multiple electromagnetic, mechanical, and
spin degrees of freedom.Comment: 19 pages, 9 figure
Quantitative Relativistic Effects in the Three-Nucleon Problem
The quantitative impact of the requirement of relativistic invariance in the
three-nucleon problem is examined within the framework of Poincar\'e invariant
quantum mechanics. In the case of the bound state, and for a wide variety of
model implementations and reasonable interactions, most of the quantitative
effects come from kinematic factors that can easily be incorporated within a
non-relativistic momentum-space three-body code.Comment: 15 pages, 15 figure
An analytical treatment of the Clock Paradox in the framework of the Special and General Theories of Relativity
In this paper we treat the so called clock paradox in an analytical way by
assuming that a constant and uniform force F of finite magnitude acts
continuously on the moving clock along the direction of its motion assumed to
be rectilinear. No inertial motion steps are considered. The rest clock is
denoted as (1), the to-and-fro moving clock is (2), the inertial frame in which
(1) is at rest in its origin and (2) is seen moving is I and, finally, the
accelerated frame in which (2) is at rest in its origin and (1) moves forward
and backward is A. We deal with the following questions: I) What is the effect
of the finite force acting on (2) on the proper time intervals measured by the
two clocks when they reunite? Does a differential aging between the two clocks
occur, as it happens when inertial motion and infinite values of the
accelerating force is considered? The Special Theory of Relativity is used in
order to describe the hyperbolic motion of (2) in the frame I II) Is this
effect an absolute one, i.e. does the accelerated observer A comoving with (2)
obtain the same results as that in I, both qualitatively and quantitatively, as
it is expected? We use the General Theory of Relativity in order to answer this
question.Comment: LaTex2e, 19 pages, no tables, no figures. Rewritten version, it
amends the previous one whose results about the treatment with General
Relativity were wrong. References added. Eq. (55) corrected. More refined
version. Comments and suggestions are warmly welcom
The effect of geometry on charge confinement in three dimensions
We show that, in contrast to the flat case, the Maxwell theory is not
confining in the background of the three dimensional BTZ black-hole (covering
space). We also study the effect of the curvature on screening behavior of
Maxwell-Chern-Simons model in this space-time.Comment: 8 pages. To be published in Europhysics Letter
The equivalence principle, uniformly accelerated reference frames, and the uniform gravitational field
The relationship between uniformly accelerated reference frames in flat
spacetime and the uniform gravitational field is examined in a relativistic
context. It is shown that, contrary to previous statements in the pages of this
journal, equivalence does not break down in this context. No restrictions to
Newtonian approximations or small enclosures are necessary
First Order Relativistic Three-Body Scattering
Relativistic Faddeev equations for three-body scattering at arbitrary
energies are formulated in momentum space and in first order in the two-body
transition-operator directly solved in terms of momentum vectors without
employing a partial wave decomposition. Relativistic invariance is incorporated
within the framework of Poincare invariant quantum mechanics, and presented in
some detail.
Based on a Malfliet-Tjon type interaction, observables for elastic and
break-up scattering are calculated up to projectile energies of 1 GeV. The
influence of kinematic and dynamic relativistic effects on those observables is
systematically studied. Approximations to the two-body interaction embedded in
the three-particle space are compared to the exact treatment.Comment: 26 pages, 13 figure
N-terminal and core-domain random mutations in human topoisomerase II α conferring bisdioxopiperazine resistance
AbstractRandom mutagenesis of human topoisomerase II α cDNA followed by functional expression in yeast cells lacking endogenous topoisomerase II activity in the presence of ICRF-187, identified five functional mutations conferring cellular bisdioxopiperazine resistance. The mutations L169F, G551S, P592L, D645N, and T996L confer >37, 37, 18, 14, and 19 fold resistance towards ICRF-187 in a 24 h clonogenic assay, respectively. Purified recombinant L169F protein is highly resistant towards catalytic inhibition by ICRF-187 in vitro while G551S, D645N, and T996L proteins are not. This demonstrates that cellular bisdioxopiperazine resistance can result from at least two classes of mutations in topoisomerase II; one class renders the protein non-responsive to bisdioxopiperazine compounds, while an other class does not appear to affect the catalytic sensitivity towards these drugs. In addition, our results indicate that different protein domains are involved in mediating the effect of bisdioxopiperazine compounds
Conservation laws for vacuum tetrad gravity
Ten conservation laws in useful polynomial form are derived from a Cartan
form and Exterior Differential System (EDS) for the tetrad equations of vacuum
relativity. The Noether construction of conservation laws for well posed EDS is
introduced first, and an illustration given, deriving 15 conservation laws of
the free field Maxwell Equations from symmetries of its EDS. The Maxwell EDS
and tetrad gravity EDS have parallel structures, with their numbers of
dependent variables, numbers of generating 2-forms and generating 3-forms, and
Cartan character tables all in the ratio of 1 to 4. They have 10 corresponding
symmetries with the same Lorentz algebra, and 10 corresponding conservation
laws.Comment: Final version with additional reference
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