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Insight into Stagnating Life Expectancy: Analysing Cause of Death Patterns across Socio-economic Groups
This article analyzes the complexity of female longevity improvements. As socio-economic status is found to influence health and mortality, we partition all individuals, at each age in every year, into five socio-economic groups based on an affluence measure that combine an individual’s income and wealth. We identify the particular socio-economic groups that have been driving the standstill for Danish females. Within each socio-economic group, we further analyze the cause of death patterns. The decline in life expectancy for Danish females is present for four out of five subgroups, however with particular large decreases for the low-middle and middle affluence groups. Cancers, smoking related causes, and other diseases particularly contribute to the stagnation. Moreover, cardiovascular and cerebrovascular diseases are found to be important for capturing the following catch-up in longevity
Photoionization and Photoelectric Loading of Barium Ion Traps
Simple and effective techniques for loading barium ions into linear Paul
traps are demonstrated. Two-step photoionization of neutral barium is achieved
using a weak intercombination line (6s2 1S0 6s6p 3P1, 791 nm) followed by
excitation above the ionization threshold using a nitrogen gas laser (337 nm).
Isotopic selectivity is achieved by using a near Doppler-free geometry for
excitation of the triplet 6s6p 3P1 state. Additionally, we report a
particularly simple and efficient trap loading technique that employs an
in-expensive UV epoxy curing lamp to generate photoelectrons.Comment: 5 pages, Accepted to PRA 3/20/2007 -fixed typo -clarified figure 3
caption -added reference [15
Mesoscopic atomic entanglement for precision measurements beyond the standard quantum limit
Squeezing of quantum fluctuations by means of entanglement is a well
recognized goal in the field of quantum information science and precision
measurements. In particular, squeezing the fluctuations via entanglement
between two-level atoms can improve the precision of sensing, clocks,
metrology, and spectroscopy. Here, we demonstrate 3.4 dB of metrologically
relevant squeezing and entanglement for ~ 10^5 cold cesium atoms via a quantum
nondemolition (QND) measurement on the atom clock levels. We show that there is
an optimal degree of decoherence induced by the quantum measurement which
maximizes the generated entanglement. A two-color QND scheme used in this paper
is shown to have a number of advantages for entanglement generation as compared
to a single color QND measurement.Comment: 6 pages+suppl, PNAS forma
Non-Destructive Identification of Cold and Extremely Localized Single Molecular Ions
A simple and non-destructive method for identification of a single molecular
ion sympathetically cooled by a single laser cooled atomic ion in a linear Paul
trap is demonstrated. The technique is based on a precise determination of the
molecular ion mass through a measurement of the eigenfrequency of a common
motional mode of the two ions. The demonstrated mass resolution is sufficiently
high that a particular molecular ion species can be distinguished from other
equally charged atomic or molecular ions having the same total number of
nucleons
Anti-tumour therapeutic efficacy of OX40L in murine tumour model
OX40 ligand (OX40L), a member of TNF superfamily, is a co-stimulatory molecule involved in T cell activation. Systemic administration of mOX40L fusion protein significantly inhibited the growth of experimental lung metastasis and subcutaneous (s.c.) established colon (CT26) and breast (4T1) carcinomas. Vaccination with OX40L was significantly enhanced by combination treatment with intra-tumour injection of a disabled infectious single cycle-herpes simplex virus (DISC-HSV) vector encoding murine granulocyte macrophage-colony stimulating factor (mGM-CSF). Tumour rejection in response to OX40L therapy required functional CD4+ and CD8+ T cells and correlated with splenocyte cytotoxic T lymphocytes (CTLs) activity against the AH-1 gp70 peptide of the tumour associated antigen expressed by CT26 cells. These results demonstrate the potential role of the OX40L in cancer immunotherapy
Echo Spectroscopy of Atomic Dynamics in a Gaussian Trap via Phase Imprints
We report on the collapse and revival of Ramsey fringe visibility when a
spatially dependent phase is imprinted in the coherences of a trapped ensemble
of two-level atoms. The phase is imprinted via the light shift from a Gaussian
laser beam which couples the dynamics of internal and external degrees of
freedom for the atoms in an echo spectroscopy sequence. The observed revivals
are directly linked to the oscillatory motion of atoms in the trap. An
understanding of the effect is important for quantum state engineering of
trapped atoms
Inhomogeneous Light Shift Effects on Atomic Quantum State Evolution in Non-Destructive Measurements
Various parameters of a trapped collection of cold and ultracold atoms can be
determined non--destructively by measuring the phase shift of an off--resonant
probe beam, caused by the state dependent index of refraction of the atoms. The
dispersive light--atom interaction, however, gives rise to a differential light
shift (AC Stark shift) between the atomic states which, for a nonuniform probe
intensity distribution, causes an inhomogeneous dephasing between the atoms. In
this paper, we investigate the effects of this inhomogeneous light shift in
non--destructive measurement schemes. We interpret our experimental data on
dispersively probed Rabi oscillations and Ramsey fringes in terms of a simple
light shift model which is shown to describe the observed behavior well.
Furthermore, we show that by using spin echo techniques, the inhomogeneous
phase shift distribution between the two clock levels can be reversed.Comment: 9 pages, 7 figures, updated introduction and reference lis
Two-dimensional epitaxial superconductor-semiconductor heterostructures: A platform for topological superconducting networks
Progress in the emergent field of topological superconductivity relies on
synthesis of new material combinations, combining superconductivity, low
density, and spin-orbit coupling (SOC). For example, theory [1-4] indicates
that the interface between a one-dimensional (1D) semiconductor (Sm) with
strong SOC and a superconductor (S) hosts Majorana modes with nontrivial
topological properties [5-8]. Recently, epitaxial growth of Al on InAs
nanowires was shown to yield a high quality S-Sm system with uniformly
transparent interfaces [9] and a hard induced gap, indicted by strongly
suppressed sub gap tunneling conductance [10]. Here we report the realization
of a two-dimensional (2D) InAs/InGaAs heterostructure with epitaxial Al,
yielding a planar S-Sm system with structural and transport characteristics as
good as the epitaxial wires. The realization of 2D epitaxial S-Sm systems
represent a significant advance over wires, allowing extended networks via
top-down processing. Among numerous potential applications, this new material
system can serve as a platform for complex networks of topological
superconductors with gate-controlled Majorana zero modes [1-4]. We demonstrate
gateable Josephson junctions and a highly transparent 2D S-Sm interface based
on the product of excess current and normal state resistance
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