5,383 research outputs found
Self-assembly and crystallisation of indented colloids at a planar wall
We report experimental and simulation studies of the structure of a monolayer
of indented ("lock and key") colloids, on a planar surface. On adding a
non-absorbing polymer with prescribed radius and volume fraction, depletion
interactions are induced between the colloids, with controlled range and
strength. For spherical particles, this leads to crystallisation, but the
indented colloids crystallise less easily than spheres, in both simulation and
experiment. Nevertheless, simulations show that indented colloids do form
plastic (rotator) crystals. We discuss the conditions under which this occurs,
and the possibilities of lower-symmetry crystal states. We also comment on the
kinetic accessibility of these states.Comment: 8 pages, 8 figure
The Early Middle Palaeolithic of Britain and Jersey: reconnecting the Saalian occupations of the Channel Region
The Early Middle Palaeolithic of southern Britain is best represented by the record recovered from
within the terraces of the Thames, within which some attempt has been made to correlate particular sites to
substage level within MIS 7. It has been suggested that there are particular features of the British record which
suggest both shared features â and differences â to the record in Northern France: firstly, an under-representation
of sites in Britain dated to late MIS7/early MIS 6 (unlike Northern France), and secondly, an apparent geographical split in the manufacture of handaxes versus Levallois debitage between the east and west. We here present
the key features of the British record, but suggest that taking a âcompare and contrastâ approach to Britain could
artificially create an impression of difference. We need to understand how our records are formed before assuming
human behaviour to be the primary driver. It is necessary to work towards a seamless characterisation of northwest European landscapes, taking account the regional filters created by, for instance, local conditions of preservation and release, and research tradition, before addressing such apparent differences. British research has
tended to focus on La Manche as a barrier, and the timing and impact of the creation of the channel upon human
access to Britain. We here suggest ways in which we can start looking at this area, not as a barrier, but an
inhabited landscape, concentrating on what we can learn from sites located around the margins of this now
inaccessible, submerged place. The site of La Cotte de St. Brelade, Jersey provides us with an important window
into the landscapes of La Manche. This site preserves the longest Middle Palaeolithic archaeological sequence
in north-west Europe, spanning from at least 240,000 BP through to MIS3. The Saalian sequence is some 5m
thick, and divided into 10 major units, all rich in artefacts. New work enables changing Neanderthal behaviour
throughout the sequence to be explored in relation to changes in regional climate and environment, as well as
starting to repopulate the space between Britain and the continent. Building on these observations, we can begin
to reflect of how space was used by Neanderthals between Great Britain and the rest of the European continent
'I just want a job' : what do we really know about young people in jobs without training?
Over recent years, a central concern of policy has been to drive up post-16 participation rates in full-time education and address the needs of young people not in education, employment or training (NEET). As a result, young people who enter work which is classified as 'without training' at 16/17 have largely been ignored. However, the decision to Raise the Participation Age (RPA) for continuing in learning for all 17-year olds from 2013 and for all 18-year olds from 2015 in England, together with a growing unease about the impact of the current recession on youth unemployment rates, have revived interest in the 'jobs without training' (JWT) group. This paper draws on the findings from two studies: first, a qualitative study in two contrasting local labour markets, of young people in JWT, together with their employers and parents; and second, an evaluation of the Learning Agreement Pilots (LAP), which was the first policy initiative in England targeted at the JWT group. Both studies reveal a dearth of understanding about early labour market entrants and a lack of policy intervention and infrastructure to support the needs of the JWT group throughout the UK. From this, it is concluded that questionable assumptions have been made about the composition and the aspirations of young people in JWT, and their employers, on the basis of little or no evidence. As a consequence, a policy 'quick fix' to satisfy the RPA agenda will not easily be achieved. If the decision to raise the participation age is adopted also by the Welsh and Scottish parliaments, similar challenges may have to be faced
Do Neural Factors Underlie Age Differences in Rapid Ankle Torque Development?
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111232/1/j.1532-5415.1996.tb03737.x.pd
Short-Term Transport Stress and Supplementation Alter Immune Function in Aged Horses
Long-distance transport is associated with stress-related changes in equine immune function, and shipping-associated illnesses are often reported. Horses are frequently transported short distances, yet the effects of short-term transport on immune function remain largely unknown. Twelve horses, aged 15â30 yr, were assigned to either the control (n = 6) or treatment (n = 6) groups; treatment horses received a daily antioxidant supplement 3 weeks before and after transport. All horses were transported for approximately 1.5â2 hr on Day 0. Blood was collected via jugular venipuncture at 15-min pre- and post-transport and on Days â21, 1, 3, 7, 14, and 21. Body temperature, heart rate, body weight, total cortisol, and gene expression of IFNÎł, IL-1ÎČ, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12α, IL-17α, SAA1, and TNFα in whole blood were measured. Peripheral blood mononuclear cells were isolated, stimulated with PMA/ionomycin, and stained for IFNÎł and TNFα before analysis via flow cytometry. Statistical analyses were performed with significance set at P \u3c 0.05 (SAS 9.4). Transport and supplementation did not appear to affect body weight, heart rate, IL-4, IL-8, IL-12α, IL-17α, change (Î) in the % and mean fluorescence intensity (MFI) of IFNÎł+ lymphocytes after stimulation, or Î in the % and MFI of TNFα+ lymphocytes after stimulation. Supplementation decreased IL-1ÎČ and SAA1 expression. Transport increased total cortisol concentration, body temperature, and IL-2, IL-6, and IL-10 expression but decreased IL-1ÎČ, TNFα, and IFNÎł expression. Short-term transportation affected physiological, endocrine, and immune responses; supplementation may ameliorate inflammation in aged horses. Immune responses were most altered at 15-min post-transport and typically recovered by Day 1, suggesting that horses may be vulnerable to disease during and almost immediately after short-term transport
Metabolic Differentiation of Early Lyme Disease from Southern Tick-associated Rash Illness (STARI)
Lyme disease, the most commonly reported vector-borne disease in the United States, results from infection with Borrelia burgdorferi. Early clinical diagnosis of this disease is largely based on the presence of an erythematous skin lesion for individuals in high-risk regions. This, however, can be confused with other illnesses including southern tick-associated rash illness (STARI), an illness that lacks a defined etiological agent or laboratory diagnostic test, and is coprevalent with Lyme disease in portions of the eastern United States. By applying an unbiased metabolomics approach with sera retrospectively obtained from well-characterized patients, we defined biochemical and diagnostic differences between early Lyme disease and STARI. Specifically, a metabolic biosignature consisting of 261 molecular features (MFs) revealed that altered N-acyl ethanolamine and primary fatty acid amide metabolism discriminated early Lyme disease from STARI. Development of classification models with the 261-MF biosignature and testing against validation samples differentiated early Lyme disease from STARI with an accuracy of 85 to 98%. These findings revealed metabolic dissimilarity between early Lyme disease and STARI, and provide a powerful and new approach to inform patient management by objectively distinguishing early Lyme disease from an illness with nearly identical symptoms
Comparative effectiveness, safety, and costs of rivaroxaban and warfarin among morbidly obese patients with atrial fibrillation.
BACKGROUND: There are limited data regarding clinical outcomes and healthcare resource utilization of direct oral anticoagulants (DOACs) in patients with atrial fibrillation (AF) who are morbidly obese (body mass index \u3e40 kg/m
METHODS: Using data from 2 US healthcare claims databases, we identified patients initiating rivaroxaban or warfarin who had â„1 medical claim with an AF diagnosis, a diagnostic code for morbid obesity (ICD-9: 278.01, V85.4%; ICD-10: E66.01%, E66.2%, Z68.4%), and a minimum continuous enrollment of 12 months before and 3 months after treatment initiation. Patients were excluded if they had mitral stenosis, a mechanical heart valve procedure, an organ/tissue transplant, or an oral anticoagulant prescription prior to the index date. Rivaroxaban and warfarin patients were 1:1 propensity score matched. Conditional logistic regression was used to compare ischemic stroke/systemic embolism and major bleeding risk. Generalized linear models were used to compare healthcare resource utilization and costs.
RESULTS: A total of 3563 matched pairs of morbidly obese AF patients treated with rivaroxaban or warfarin were identified. The majority (81.4%) of patients in the rivaroxaban cohort were receiving the 20 mg dose. The rivaroxaban and warfarin cohorts were well balanced after propensity score matching. The risks of ischemic stroke/systemic embolism and major bleeding were similar for rivaroxaban and warfarin users (stroke/systemic embolism: 1.5% vs 1.7%; odds ratio [OR]: 0.88; 95% confidence interval [CI]: 0.60, 1.28; P = .5028; major bleeding: 2.2% vs 2.7%; OR: 0.80; 95% CI: 0.59, 1.08; P = .1447). Total healthcare costs including medication costs per patient per year (PPPY) were significantly lower with rivaroxaban versus warfarin (52,418; P = .0025), which was primarily driven by lower hospitalization rate (50.2% vs 54.1%; P = .0008), shorter length of stay (7.5 vs 9.1 days; P = .0010), and less outpatient service utilization (86 vs 115 visits PPPY; P \u3c .0001).
CONCLUSIONS: Morbidly obese AF patients treated with rivaroxaban had comparable risk of ischemic stroke/systemic embolism and major bleeding as those treated with warfarin, but lower healthcare resource utilization and costs
Rivaroxaban versus warfarin treatment among morbidly obese patients with venous thromboembolism: Comparative effectiveness, safety, and costs.
INTRODUCTION: Limited data exist on direct-acting oral anticoagulants in morbidly obese patients with venous thromboembolism (VTE). We compared clinical and health/economic outcomes with rivaroxaban versus warfarin for VTE treatment in morbidly obese patients.
MATERIALS AND METHODS: This retrospective 1:1 propensity score matched cohort study analyzed data from 2 US claims databases. VTE patients initiating rivaroxaban or warfarin were identified who had diagnosis codes for morbid obesity (ICD-9:278.01,V85.4; ICD-10:E66.01,E66.2,Z68.4) 12âŻmonths pre- or 3âŻmonths post-initiation and followed â„3âŻmonths. Intent-to-treat (ITT) and on-treatment (OT) analyses were conducted using conditional logistic regression and generalized linear models to compare recurrent VTE and major bleeding risks, healthcare resource utilization (HRU), and per patient per year (PPPY) costs.
RESULTS: In total, 2890 matched pairs of morbidly obese VTE patients initiating rivaroxaban or warfarin were identified. Risks of recurrent VTE (ITT: OR: 0.99; 95% CI: 0.85-1.14) and major bleeding (OT: OR: 0.75; 95% CI: 0.47-1.19) were similar for cohorts. Anti-Factor Xa laboratory measurement was performed on
CONCLUSIONS: Morbidly obese VTE patients receiving rivaroxaban had similar risks of recurrent VTE and major bleeding versus warfarin. Rivaroxaban treatment yielded significantly less HRU and total medical costs, with similar total healthcare costs between groups
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