10,226 research outputs found
The assessment and management of pain in older people : a systematic review of the literature
This paper presents the findings of a systematic literature which was carried out to determine the most appropriate strategies that could be carried out for the assessment and management of pain in residents living in care homes. Five hundred and seventy-one papers were initially identified and from this total 70 papers were found to be appropriate. These papers were organised into five key themes; Assessment & Behavioural Assessment, Barriers/Attitudes/Perceptions, Cognitive Behavioural Therapy, Complementary Therapies and Education/Guidelines. Most of the papers related to pain in this group were pharmacological suggesting that health care professionals generally feel that pharmacological approaches are the only way to manage pain in this group. Nevertheless, the non-pharmacological papers do suggest that there are other methods of pain control which should be considered. Recommendations for further research are made.Burdett Trust for Nursin
Scattering of low-energy electrons and positrons by atomic beryllium: Ramsauer-Townsend effect
Total cross sections for the scattering of low-energy electrons and positrons
by atomic beryllium in the energy range below the first inelastic thresholds
are calculated. A Ramsauer-Townsend minimum is seen in the electron scattering
cross sections, while no such effect is found in the case of positron
scattering. A minimum total cross section of 0.016 a.u. at 0.0029 eV is
observed for the electron case. In the limit of zero energy, the cross sections
yield a scattering length of -0.61 a.u. for electron and +13.8 a.u. for
positron scattering
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Cryo-EM structure of the potassium-chloride cotransporter KCC4 in lipid nanodiscs.
Cation-chloride-cotransporters (CCCs) catalyze transport of Cl- with K+ and/or Na+across cellular membranes. CCCs play roles in cellular volume regulation, neural development and function, audition, regulation of blood pressure, and renal function. CCCs are targets of clinically important drugs including loop diuretics and their disruption has been implicated in pathophysiology including epilepsy, hearing loss, and the genetic disorders Andermann, Gitelman, and Bartter syndromes. Here we present the structure of a CCC, the Mus musculus K+-Cl- cotransporter (KCC) KCC4, in lipid nanodiscs determined by cryo-EM. The structure, captured in an inside-open conformation, reveals the architecture of KCCs including an extracellular domain poised to regulate transport activity through an outer gate. We identify binding sites for substrate K+ and Cl- ions, demonstrate the importance of key coordinating residues for transporter activity, and provide a structural explanation for varied substrate specificity and ion transport ratio among CCCs. These results provide mechanistic insight into the function and regulation of a physiologically important transporter family
Experimental study of the fluctuation theorem in a nonequilibrium steady state
The fluctuation theorem (FT) quantifies the probability of second law violations in small systems over short time scales. While this theorem has been experimentally demonstrated for systems that are perturbed from an initial equilibrium state, there are a number of studies suggesting that the theorem applies asymptotically in the long time limit to systems in a nonequilibrium steady state. The asymptotic application of the FT to such nonequilibrium steady states has been referred to in the literature as the steady-state fluctuation theorem (or SSFT). In this paper, we demonstrate experimentally the application of the FT to nonequilibrium steady states, using a colloidal particle localized in a translating optical trap. Furthermore, we show, for this colloidal system, that the FT holds under nonequilibrium steady states for all time, and not just in the long time limit, as in the SSFT
Spin entanglement, decoherence and Bohm's EPR paradox
We obtain criteria for entanglement and the EPR paradox
for spin-entangled particles and analyse the effects of decoherence caused
by absorption and state purity errors. For a two qubit photonic state,
entanglement can occur for all transmission efficiencies. In this case,
the state preparation purity must be above a threshold value. However,
Bohm’s spin EPR paradox can be achieved only above a critical level of
loss. We calculate a required efficiency of 58%, which appears achievable
with current quantum optical technologies. For a macroscopic number of
particles prepared in a correlated state, spin entanglement and the EPR
paradox can be demonstrated using our criteria for efficiencies η > 1/3
and η > 2/3 respectively. This indicates a surprising insensitivity to loss
decoherence, in a macroscopic system of ultra-cold atoms or photons
Seasonal Variation in 25(OH)D at Aberdeen (57°N) and Bone Health Indicators- Could Holidays in the Sun and Cod Liver Oil Supplements Alleviate Deficiency?
Vitamin D has been linked with many health outcomes. The aim of this longitudinal study, was to assess predictors of seasonal variation of 25-hydroxy-vitamin D (25(OH)D) (including use of supplements and holidays in sunny destinations) at a northerly latitude in the UK (57°N) in relation to bone health indicators. 365 healthy postmenopausal women (mean age 62.0 y (SD 1.4)) had 25(OH)D measurements by immunoassay, serum C-telopeptide (CTX), estimates of sunlight exposure (badges of polysulphone film), information regarding holidays in sunny destinations, and diet (from food diaries, including use of supplements such as cod liver oil (CLO)) at fixed 3-monthly intervals over 15 months (subject retention 88%) with an additional 25(OH)D assessment in spring 2008. Bone mineral density (BMD) at the lumbar spine (LS) and dual hip was measured in autumn 2006 and spring 2007 (Lunar I-DXA). Deficiency prevalence (25(OH)
Molecular electrostatic potentials by systematic molecular fragmentation
A simple method is presented for estimating the molecular electrostatic potential in and around molecules using systematic molecular fragmentation. This approach estimates the potential directly from the electron density. The accuracy of the method is established for a set of organic molecules and ions. The utility of the approach is demonstrated by estimating the binding energy of a water molecule in an internal cavity in the protein ubiquitin
Intermediate- to high-energy positrons scattered by alkali-metal atoms
We present calculations of the differential, integrated elastic, and total cross sections for positrons scattered from alkali-metal atoms. The energy of the positrons ranges from 10 eV to 1000 eV. In the calculations we use parameter-free model potentials for the correlation-polarization and absorption interactions. The absorption potential used for positron scattering is based on a quasifree model that we recently proposed and tested for the noble-gas targets. For positron–alkali-metal scattering the model potentials have produced reliable scattering cross sections over the extended range of impact energies when compared against the available experimental data
Low-energy differential scattering of electrons and positrons from noble gases
Calculations of cross sections for electron (e−) and positron (e+) scattering from ground-state He, Ne, Ar, Kr, and Xe at projectile energies below the lowest inelastic thresholds are presented. The main focus in the present work is on the differential cross sections, since angular distributions depend sensitively on the choice of interaction potentials used in the calculations. A part of the interaction potential used in the calculations includes a parameter-free correlation-polarization potential which is (a) based on physical ideas of what a correlation-polarization potential should be, (b) different for various target gases, and (c) distinct for electron and positron scattering. The present calculations of differential cross sections predict the locations of the principal maxima and minima with good accuracy and the shapes of the calculated differential cross-section curves compare quite well with available experimental cross sections
Research notes: A partially male-sterile mutant in soybeans
An entry consisting mostly of plants having little to no seed set was found amidst the breeding material of Dr. Walter R. Fehr (Iowa State University) in 1975. The entry was descendent from germplasm population AP6(Sl)Cl, which was described by Fehr and Ortiz (1975). Investigations have revealed that partial male sterility was the primary cause leading to reduced seed set (Stelly, 1979)
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