2,795 research outputs found
Ephemeral Londoners: Modelling Lower Class Migration to Eighteenth Century London
Between 1750 and 1801 the population of London grew from approximately 750,000 to 1.1 million people. Relocating to London in the eighteenth century only occasionally generated a paper trail, but a significant number of failed migrants were rounded up for ‘wandering and begging’ on the streets and sent back from whence they came to their parish of legal settlement. Records of these removals have been digitised and are used in this paper to model migration into London, to throw light onto the patterns of movement at this time
First principles theory of chiral dichroism in electron microscopy applied to 3d ferromagnets
Recently it was demonstrated (Schattschneider et al., Nature 441 (2006),
486), that an analogue of the X-ray magnetic circular dichroism (XMCD)
experiment can be performed with the transmission electron microscope (TEM).
The new phenomenon has been named energy-loss magnetic chiral dichroism (EMCD).
In this work we present a detailed ab initio study of the chiral dichroism in
the Fe, Co and Ni transition elements. We discuss the methods used for the
simulations together with the validity and accuracy of the treatment, which
can, in principle, apply to any given crystalline specimen. The dependence of
the dichroic signal on the sample thickness, accuracy of the detector position
and the size of convergence and collection angles is calculated.Comment: 9 pages, 6 figures, submitted to Physical Review
Plant Selections for Vegetative Channels: Evaluation of Seven Aquatic Plant Species for Susceptibility to Five Species of Phytophthora
(5S,6R)-5-Methyl-6-phenyl-4-propyl-1,3,4-oxadiazinane-2-thione
The title molecule, C13H18N2OS, is an oxadiazinanthione derived from (1R,2S)-norephedrine. There are two molecules in the asymmetric. Both adopt roughly half-chair conformations; however, the 5-position carbon orients out of opposite faces of the oxadiazinanthiones plane in the two molecules. In the crystal structure, they are oriented as a dimer linked by a pair of N—H⋯S hydrogen bonds. The absolute configuration has been established from anomalous dispersion and confirms the known stereochemistry based on the synthetic procedure
Experimental detection of entanglement via witness operators and local measurements
In this paper we address the problem of detection of entanglement using only
few local measurements when some knowledge about the state is given. The idea
is based on an optimized decomposition of witness operators into local
operators. We discuss two possible ways of optimizing this local decomposition.
We present several analytical results and estimates for optimized detection
strategies for NPT states of 2x2 and NxM systems, entangled states in 3 qubit
systems, and bound entangled states in 3x3 and 2x4 systems.Comment: 24 pages, 2 figures. Contribution to the proceedings of the
International Conference on Quantum Information in Oviedo, Spain (July 13-18,
2002). Error in W_W1-witness Eq. (35) corrected as well as minor typos.
Reference adde
The Challenges of Multimorbidity from the Patient Perspective
BACKGROUND
Although multiple co-occurring chronic illnesses within the same individual are increasingly common, few studies have examined the challenges of multimorbidity from the patient perspective.
OBJECTIVE
The aim of this study is to examine the self-management learning needs and willingness to see non-physician providers of patients with multimorbidity compared to patients with single chronic illnesses. DESIGN. This research is designed as a cross-sectional survey.
PARTICIPANTS
Based upon ICD-9 codes, patients from a single VHA healthcare system were stratified into multimorbidity clusters or groups with a single chronic illness from the corresponding cluster. Nonproportional sampling was used to randomly select 720 patients.
MEASUREMENTS
Demographic characteristics, functional status, number of contacts with healthcare providers, components of primary care, self-management learning needs, and willingness to see nonphysician providers.
RESULTS
Four hundred twenty-two patients returned surveys. A higher percentage of multimorbidity patients compared to single morbidity patients were "definitely" willing to learn all 22 self-management skills, of these only 2 were not significant. Compared to patients with single morbidity, a significantly higher percentage of patients with multimorbidity also reported that they were "definitely" willing to see 6 of 11 non-physician healthcare providers.
CONCLUSIONS
Self-management learning needs of multimorbidity patients are extensive, and their preferences are consistent with team-based primary care. Alternative methods of providing support and chronic illness care may be needed to meet the needs of these complex patients.US Department of Veterans Affairs (01-110, 02-197); Agency for Healthcare Research and Quality (K08 HS013008-02
Strain Relaxation Mechanisms and Local Structural Changes in Si_{1-x}$Ge_{x} Alloys
In this work, we address issues pertinent to the understanding of the
structural and electronic properties of Si_{1-x} Ge_{x}alloys, namely, (i) how
does the lattice constant mismatch between bulk Si and bulk Ge manifests itself
in the alloy system? and (ii) what are the relevant strain release mechanisms?
To provide answers to these questions, we have carried out an in-depth study of
the changes in the local geometric and electronic structures arising from the
strain relaxation in Si_{1-x} Ge_{x} alloys using an ab initio molecular
dynamics scheme. The optimized lattice constant, while exhibiting a general
trend of linear dependence on the composition (Vegard's law), shows a negative
deviation from Vegard's law in the vicinity of x=0.5. We delineate the
mechanisms responsible for each one of the above features. We show that the
radial-strain relaxation through bond stretching is responsible for the overall
trend of linear dependence of the lattice constant on the composition. On the
other hand, the negative deviation from Vegard's law is shown to arise from the
angular-strain relaxation.Comment: 21 pages, 7 figure
Dinosaur tracks from the Kilmaluag Formation (Bathonian, Middle Jurassic) of Score Bay, Isle of Skye, Scotland, UK
Tracks of a juvenile theropod dinosaur with footprint lengths of between 2 and 9 cm as well as adults of the same ichnospecies with footprints of about 15–25 cm in length were found in the Bathonian (Middle Jurassic) Kilmaluag Formation of Score Bay, northwestern Trotternish Peninsula, Isle of Skye, Scotland, UK. Two footprint sizes occur together on the same bedding plane in the central portion of Score Bay, both in situ and on loose blocks. Another horizon containing footprints above this was also identified. The footprints from the lowest horizon were produced in a desiccated silty mud that was covered with sand. A close association of both adults and juveniles with similar travel direction indicated by the footprints may suggest post-hatching care in theropod dinosaurs. Other footprints, produced on a rippled sandy substrate, have been found on the slightly higher bedding plane at this locality. Loose blocks found 130 m to the northeast in the central part of Score Bay have not been correlated with any in situ sediments, but were preserved in a similar manner to those from the higher bedding plane. These tracks represent the youngest dinosaur remains yet found in Scotland
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