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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
Andreev rectifier: a nonlocal conductance signature of topological phase transitions
The proximity effect in hybrid superconductor-semiconductor structures,
crucial for realizing Majorana edge modes, is complicated to control due to its
dependence on many unknown microscopic parameters. In addition, defects can
spoil the induced superconductivity locally in the proximitised system which
complicates measuring global properties with a local probe. We show how to use
the nonlocal conductance between two spatially separated leads to probe three
global properties of a proximitised system: the bulk superconducting gap, the
induced gap, and the induced coherence length. Unlike local conductance
spectroscopy, nonlocal conductance measurements distinguish between
non-topological zero-energy modes localized around potential inhomogeneities,
and true Majorana edge modes that emerge in the topological phase. In addition,
we find that the nonlocal conductance is an odd function of bias at the
topological phase transition, acting as a current rectifier in the low-bias
limit. More generally, we identify conditions for crossed Andreev reflection to
dominate the nonlocal conductance and show how to design a Cooper pair splitter
in the open regime.Comment: 11 pages, 13 figure
The evolution of the galactic morphological types in clusters
The morphological types of galaxies in nine clusters in the redshift range
0.1<z<0.25 are derived from very good seeing images taken at the NOT and the La
Silla Danish telescopes. With the purpose of investigating the evolution of the
fraction of different morphological types with redshift, we compare our results
with the morphological content of nine distant clusters studied by the MORPHS
group, five clusters observed with HST-WFPC2 at redshift z = 0.2-0.3, and
Dressler's (1980) large sample of nearby clusters. After having checked the
reliability of our morphological classification both in an absolute sense and
relative to the MORPHS scheme, we analyze the relative occurrence of
elliptical, S0 and spiral galaxies as a function of the cluster properties and
redshift. We find a large intrinsic scatter in the S0/E ratio, mostly related
to the cluster morphology. In particular, in our cluster sample, clusters with
a high concentration of ellipticals display a low S0/E ratio and, vice-versa,
low concentration clusters have a high S0/E. At the same time, the trend of the
morphological fractions and ratios with redshift clearly points to a
morphological evolution: as the redshift decreases, the S0 population tends to
grow at the expense of the spiral population, whereas the frequency of Es
remains almost constant. We also analyze the morphology-density (MD) relation
in our clusters and find that -similarly to higher redshift clusters- a good MD
relation exists in the high-concentration clusters, while it is absent in the
less concentrated clusters. Finally, the comparison of the MD relation in our
clusters with that of the D97 sample suggests that the transformation of
spirals into S0 galaxies becomes more efficient with decreasing local density.Comment: 24 pages including 11 figures and 4 tables, accepted for publication
in Ap
Fast sensing of double-dot charge arrangement and spin state with an rf sensor quantum dot
Single-shot measurement of the charge arrangement and spin state of a double
quantum dot are reported, with measurement times down to ~ 100 ns. Sensing uses
radio-frequency reflectometry of a proximal quantum dot in the Coulomb blockade
regime. The sensor quantum dot is up to 30 times more sensitive than a
comparable quantum point contact sensor, and yields three times greater signal
to noise in rf single-shot measurements. Numerical modeling is qualitatively
consistent with experiment and shows that the improved sensitivity of the
sensor quantum dot results from reduced screening and lifetime broadening.Comment: related papers at http://marcuslab.harvard.ed
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
Evolution of Galaxy morphologies in Clusters
We have studied the evolution of galaxian morphologies from ground-based,
good-seeing images of 9 clusters at z=0.09-0.25. The comparison of our data
with those relative to higher redshift clusters (Dressler et al. 1997) allowed
us to trace for the first time the evolution of the morphological mix at a
look-back time of 2-4 Gyr, finding a dependence of the observed evolutionary
trends on the cluster properties.Comment: 4 pages with 2 figures in Latex-Kluwer style. To be published in the
proceedings of the Granada Euroconference "The Evolution of
Galaxies.I-Observational Clues
Superconducting, Insulating, and Anomalous Metallic Regimes in a Gated Two-Dimensional Semiconductor-Superconductor Array
The superconductor-insulator transition in two dimensions has been widely
investigated as a paradigmatic quantum phase transition. The topic remains
controversial, however, because many experiments exhibit a metallic regime with
saturating low-temperature resistance, at odds with conventional theory. Here,
we explore this transition in a novel, highly controllable system, a
semiconductor heterostructure with epitaxial Al, patterned to form a regular
array of superconducting islands connected by a gateable quantum well. Spanning
nine orders of magnitude in resistance, the system exhibits regimes of
superconducting, metallic, and insulating behavior, along with signatures of
flux commensurability and vortex penetration. An in-plane magnetic field
eliminates the metallic regime, restoring the direct superconductor-insulator
transition, and improves scaling, while strongly altering the scaling exponent
Zero-Energy Modes from Coalescing Andreev States in a Two-Dimensional Semiconductor-Superconductor Hybrid Platform
We investigate zero-bias conductance peaks that arise from coalescing subgap
Andreev states, consistent with emerging Majorana zero modes, in hybrid
semiconductor-superconductor wires defined in a two-dimensional InAs/Al
heterostructure using top-down lithography and gating. The measurements
indicate a hard superconducting gap, ballistic tunneling contact, and in-plane
critical fields up to ~T. Top-down lithography allows complex geometries,
branched structures, and straightforward scaling to multicomponent devices
compared to structures made from assembled nanowires.Comment: Includes Supplementary Materia
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
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