1,143 research outputs found
The management of behavioural and psychological symptoms of dementia in the acute general medical hospital: A longitudinal cohort study
yesBackground: The acute hospital is a challenging place for a person with dementia. Behavioural and psychological symptoms of dementia (BPSD) are common and may be exacerbated by the hospital environment. Concerns have been raised about how BPSD are managed in this setting and about over reliance on neuroleptic medication. This study aimed to investigate how BPSD are managed in UK acute hospitals.
Method(s): A longitudinal cohort of 230 patients with dementia admitted to two acute NHS hospitals. BPSD were measured every four days (Behave-AD scale), as well as documentation of pharmacological prescriptions and non-pharmacological management.
Results: The overall prevalence of BPSD was 75%, with aggression and activity disturbance being the most common. Antipsychotics were prescribed for 28 (12%) patients; 70% of these prescriptions were new on admission. Benzodiazepines were prescribed for 27 (12%) patients, antidepressants were prescribed for 37 (16%) patients, and sedatives were prescribed for 14 (3%) patients. Patients who were prescribed antipsychotics, after adjusting for end of life medication, age and dementia severity, were significantly more likely to die (adjusted hazard ratio 5.78, 95% CI 1.57, 21.26, p= 0.008). Nonpharmacological
management was used in 55% of participants, most commonly psychosocial
interventions (36%) with little evidence of monitoring their effectiveness. A form of restraint was used during 50 (22%) patients’ admissions.
Conclusions: Antipsychotic medications and psychosocial interventions were the main methods used to manage BPSD; however, these were not implemented or monitored in a systematic fashion.Alzheimer's Society; BUPA Foundatio
Chirality effects in carbon nanotubes
We consider chirality related effects in optical, photogalvanic and
electron-transport properties of carbon nanotubes. We show that these
properties of chiral nanotubes are determined by terms in the electron
effective Hamiltonian describing the coupling between the electron wavevector
along the tube principal axis and the orbital momentum around the tube
circumference. We develop a theory of photogalvanic effects and a theory of
d.c. electric current, which is linear in the magnetic field and quadratic in
the bias voltage. Moreover, we present analytic estimations for the natural
circular dichroism and magneto-spatial effect in the light absorption.Comment: 23 pages, 3 figure
A Real-Space Full Multigrid study of the fragmentation of Li11+ clusters
We have studied the fragmentation of Li11+ clusters into the two
experimentally observed products (Li9+,Li2) and (Li10+,Li) The ground state
structures for the two fragmentation channels are found by Molecular Dynamics
Simulated Annealing in the framework of Local Density Functional theory.
Energetics considerations suggest that the fragmentation process is dominated
by non-equilibrium processes. We use a real-space approach to solve the
Kohn-Sham problem, where the Laplacian operator is discretized according to the
Mehrstellen scheme, and take advantage of a Full MultiGrid (FMG) strategy to
accelerate convergence. When applied to isolated clusters we find our FMG
method to be more efficient than state-of-the-art plane wave calculations.Comment: 9 pages + 6 Figures (in gzipped tar file
Residual cognitive deficits 50 years after lead poisoning during childhood
The long term neurobehavioural consequences of childhood lead poisoning are not known. In this study adult subjects with a documented history of lead poisoning before age 4 and matched controls were examined with an abbreviated battery of neuropsychological tests including measures of attention, reasoning, memory, motor speed, and current mood. The subjects exposed to lead were inferior to controls on almost all of the cognitive tasks. This pattern of widespread deficits resembles that found in children evaluated at the time of acute exposure to lead rather than the more circumscribed pattern typically seen in adults exposed to lead. Despite having completed as many years of schooling as controls, the subjects exposed to lead were lower in lifetime occupational status. Within the exposed group, performance on the neuropsychological battery and occupational status were related, consistent with the presumed impact of limitations in neuropsychological functioning on everyday life. The results suggest that many subjects exposed to lead suffered acute encephalopathy in childhood which resolved into a chronic subclinical encephalopathy with associated cognitive dysfunction still evident in adulthood. These findings lend support to efforts to limit exposure to lead in childhood
Real-space local polynomial basis for solid-state electronic-structure calculations: A finite-element approach
We present an approach to solid-state electronic-structure calculations based
on the finite-element method. In this method, the basis functions are strictly
local, piecewise polynomials. Because the basis is composed of polynomials, the
method is completely general and its convergence can be controlled
systematically. Because the basis functions are strictly local in real space,
the method allows for variable resolution in real space; produces sparse,
structured matrices, enabling the effective use of iterative solution methods;
and is well suited to parallel implementation. The method thus combines the
significant advantages of both real-space-grid and basis-oriented approaches
and so promises to be particularly well suited for large, accurate ab initio
calculations. We develop the theory of our approach in detail, discuss
advantages and disadvantages, and report initial results, including the first
fully three-dimensional electronic band structures calculated by the method.Comment: replacement: single spaced, included figures, added journal referenc
Farmland Prices: Is This Time Different?
The historical behavior of farmland prices, rental rates, and rates of return are examined by treating farmland as an asset with an infinitely long life. It is found that high (low) farmland prices relative to rents have historically preceded extended periods of low (high) net rates of return, rather than greater (smaller) growth in rents. Our analysis shows that this attribute is shared with stocks and housing, and the financial literature provides ample evidence that other assets feature it as well. The long-run relationship linking farmland prices, rents, and rates of return is analyzed. Based on this relationship, we conclude that recent trends are unlikely to be sustainable. The study explores the expected paths that farmland prices and rates of return might follow if they were to eventually conform to the average values observed in the historical sample, and concludes with a discussion of the policy implications. Recommendations for policy makers include close monitoring of farmland lending practices and institutions to allow early identification of potential problems, and identifying in advance appropriate interventions in case recent farmland market trends were to suddenly change
Benchmark Parameters for CMB Polarization Experiments
The recently detected polarization of the cosmic microwave background (CMB)
holds the potential for revealing the physics of inflation and gravitationally
mapping the large-scale structure of the universe, if so called B-mode signals
below 10^{-7}, or tenths of a uK, can be reliably detected. We provide a
language for describing systematic effects which distort the observed CMB
temperature and polarization fields and so contaminate the B-modes. We identify
7 types of effects, described by 11 distortion fields, and show their
association with known instrumental systematics such as common mode and
differential gain fluctuations, line cross-coupling, pointing errors, and
differential polarized beam effects. Because of aliasing from the small-scale
structure in the CMB, even uncorrelated fluctuations in these effects can
affect the large-scale B modes relevant to gravitational waves. Many of these
problems are greatly reduced by having an instrumental beam that resolves the
primary anisotropies (FWHM << 10'). To reach the ultimate goal of an
inflationary energy scale of 3 \times 10^{15} GeV, polarization distortion
fluctuations must be controlled at the 10^{-2}-10^{-3} level and temperature
leakage to the 10^{-4}-10^{-3} level depending on effect. For example pointing
errors must be controlled to 1.5'' rms for arcminute scale beams or a percent
of the Gaussian beam width for larger beams; low spatial frequency differential
gain fluctuations or line cross-coupling must be eliminated at the level of
10^{-4} rms.Comment: 11 pages, 5 figures, submitted to PR
Anisotropic exchange interaction of localized conduction-band electrons in semiconductor structures
The spin-orbit interaction in semiconductors is shown to result in an
anisotropic contribution into the exchange Hamiltonian of a pair of localized
conduction-band electrons. The anisotropic exchange interaction exists in
semiconductor structures which are not symmetric with respect to spatial
inversion, for instance in bulk zinc-blend semiconductors. The interaction has
both symmetric and antisymmetric parts with respect to permutation of spin
components. The antisymmetric (Dzyaloshinskii-Moriya) interaction is the
strongest one. It contributes significantly into spin relaxation of localized
electrons; in particular, it governs low-temperature spin relaxation in n-GaAs
with the donor concentration near 10^16cm-3. The interaction must be allowed
for in designing spintronic devices, especially spin-based quantum computers,
where it may be a major source of decoherence and errors
Criticality in coupled quantum spin-chains with competing ladder-like and two-dimensional couplings
Motivated by the geometry of spins in the material CaCuO, we study a
two-layer, spin-half Heisenberg model, with nearest-neighbor exchange couplings
J and \alpha*J along the two axes in the plane and a coupling J_\perp
perpendicular to the planes. We study these class of models using the
Stochastic Series Expansion (SSE) Quantum Monte Carlo simulations at finite
temperatures and series expansion methods at T=0. The critical value of the
interlayer coupling, J_\perp^c, separating the N{\'e}el ordered and disordered
ground states, is found to follow very closely a square root dependence on
. Both T=0 and finite-temperature properties of the model are
presented.Comment: 9 pages, 11 figs., 1 tabl
Studies on two stage sludge digestion, 1928-29
At head of title: State of Illinois. Department of registration and education. Division of the state Water survey."Bulletins of the state water survey": 1 leaf at end."Literature cited": p. 92.Enumeration continues from preceding title
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