2,522 research outputs found
Automated methods for surveillance of surgical site infections.
Automated data, especially from pharmacy and administrative claims, are available for much of the U.S. population and might substantially improve both inpatient and postdischarge surveillance for surgical site infections complicating selected procedures, while reducing the resources required. Potential improvements include better sensitivity, less susceptibility to interobserver variation, more uniform availability of data, more precise estimates of infection rates, and better adjustment for patients' coexisting illness
Classical and Quantum-like approaches to Charged-Particle Fluids in a Quadrupole
A classical description of the dynamics of a dissipative charged-particle
fluid in a quadrupole-like device is developed. It is shown that the set of the
classical fluid equations contains the same information as a complex function
satisfying a Schrodinger-like equation in which Planck's constant is replaced
by the time-varying emittance, which is related to the time-varying temperature
of the fluid. The squared modulus and the gradient of the phase of this complex
function are proportional to the fluid density and to the current velocity,
respectively. Within this framework, the dynamics of an electron bunch in a
storage ring in the presence of radiation damping and quantum-excitation is
recovered. Furthermore, both standard and generalized (including dissipation)
coherent states that may be associated with the classical particle fluids are
fully described in terms of the above formalism.Comment: LaTex, to appear in Physica Script
Exploring efficacy in personal constraint negotiation: an ethnography of mountaineering tourists
Limited work has explored the relationship between efficacy and personal constraint negotiation for adventure tourists, yet efficacy is pivotal to successful activity participation as it influences people’s perceived ability to cope with constraints, and their decision to use negotiation strategies. This paper explores these themes with participants of a commercially organised mountaineering expedition. Phenomenology-based ethnography was adopted to appreciate the social and cultural mountaineering setting from an emic perspective. Ethnography is already being used to understand adventure participation, yet there is considerable scope to employ it further through researchers immersing themselves into the experience. The findings capture the interaction between the ethnographer and the group members, and provide an embodied account using their lived experiences. Findings reveal that personal mountaineering skills, personal fitness, altitude sickness and fatigue were the four key types of personal constraint. Self-efficacy, negotiation-efficacy and other factors, such as hardiness and motivation, influenced the effectiveness of negotiation strategies. Training, rest days, personal health, and positive self-talk were negotiation strategies. A conceptual model illustrates these results and demonstrates the interplay between efficacy and the personal constraint negotiation journey for led mountaineers
Does free-living physical activity improve one-year following total knee arthroplasty in patients with osteoarthritis : a prospective study
Objective Total knee arthroplasty (TKA) is the gold-standard treatment for end-stage knee osteoarthritis, and the primary expectations are reduced pain and improved function. However, there is conflicting evidence regarding functional changes post-TKA. Commonly, functional changes are measured using Oxford Knee Score (OKS). No previous study has investigated physical behaviour (PB) changes in terms of volume and patterns post-TKA. The aims of this study were to explore volume and pattern changes in PB following TKA using an objective tool and to assess the correlation between this and OKS.
Design An activPAL measured the PB of individuals on a waiting list for TKA for a period of 7–8 days pre-TKA, and for the same length of time at 12 months post-TKA. OKS was completed at similar follow-up time points.
Results Thirty-three individuals completed the study, where stepping time, the number of steps and the time spent on moderate to vigorous physical activity (MVPA) (>100 steps/minute) improved significantly post-TKA p = 0.0001. Steps at 12 months post-TKA improved by 45.6% (from 4,240 to 6,174) and stepping time increased by 38.8% (from 0.98 to 1.36 hours). MVPA improved by 35 minutes at 12 months (from 6.6 to 41.7 minutes).
There were no significant correlations between PB and OKS.
Conclusion This is the first study to explore PB volumes and event-based patterns post-TKA. Activity improved in terms of volume and patterns. No correlation was found between OKS and ActivPAL, which emphasises the need to use objective methods in addition to patient reported outcome measures
Coherent States for Particle Beams in the Thermal Wave Model
In this paper, by using an analogy among {\it quantum mechanics}, {\it
electromagnetic beam optics in optical fibers}, and {\it charge particle beam
dynamics}, we introduce the concept of {\it coherent states} for charged
particle beams in the framework of the {\it Thermal Wave Model} (TWM). We give
a physical meaning of the Gaussian-like coherent structures of charged particle
distribution that are both naturally and artificially produced in an
accelerating machine in terms of the concept of coherent states widely used in
quantum mechanics and in quantum optics. According to TWM, this can be done by
using a Schr\"{o}dinger-like equation for a complex function, the so-called
{\it beam wave function} (BWF), whose squared modulus is proportional to the
transverse beam density profile, where Planck's constant and the time are
replaced by the transverse beam emittance and by the propagation coordinate,
respectively. The evolution of the particle beam, whose initial BWF is assumed
to be the simplest coherent state (ground-like state) associated with the beam,
in an infinite 1-D quadrupole-like device with small sextupole and octupole
aberrations, is analytically and numerically investigated.Comment: 21 pages, Late
The Geometry of Entanglement Sudden Death
In open quantum systems, entanglement can vanish faster than coherence. This
phenomenon is usually called sudden death of entanglement. In this paper sudden
death of entanglement is discussed from a geometrical point of view, in the
context of two qubits. A classification of possible scenarios is presented,
with important known examples classified. Theoretical and experimental
construction of other examples is suggested as well as large dimensional and
multipartite versions of the effect.Comment: 6 pages, 2 figures, references added, initial paragraph corrected,
sectioning adopted, some parts rewritten; accepted by New J. Phy
Economic Potential of Greenhouse Gas Emission Reductions: Comparative Role for Soil Sequestration in Agriculture and Forestry
We use the Agricultural Sector Model to analyze the economic potential of soil carbon sequestration as one of several agricultural greenhouse gas emission mitigation strategies, including afforestation. For low incentives on carbon emission savings, agricultural soil carbon sequestration is the most cost-efficient strategy. As incentive levels increase above $50 per ton of carbon equivalent, afforestation and biofuel production become the key strategies, while the role of soil carbon diminishes. If saturating sinks are discounted based on their net present value, the competitive economic equilibrium among agricultural mitigation strategies shifts away from soil carbon sequestration and afforestation and toward more biofuel production. Regardless of the discounting assumption and the carbon savings incentive level, the economic potential of soil carbon sequestration never attains its technical potential as estimated by soil scientists. The study also estimates the impacts of agricultural mitigation policies on welfare, prices, production, and input use in the traditional food and fiber sector and the effects of emission leakage from unregulated agricultural sources
Epidemiology of and surveillance for postpartum infections.
We screened automated ambulatory medical records, hospital and emergency room claims, and pharmacy records of 2,826 health maintenance organization (HMO) members who gave birth over a 30-month period. Full-text ambulatory records were reviewed for the 30-day postpartum period to confirm infection status for a weighted sample of cases. The overall postpartum infection rate was 6.0%, with rates of 7.4% following cesarean section and 5.5% following vaginal delivery. Rehospitalization; cesarean delivery; antistaphylococcal antibiotics; diagnosis codes for mastitis, endometritis, and wound infection; and ambulatory blood or wound cultures were important predictors of infection. Use of automated information routinely collected by HMOs and insurers allows efficient identification of postpartum infections not detected by conventional surveillance
Microbiology and atmospheric processes: research challenges concerning the impact of airborne micro-organisms on the atmosphere and climate
For the past 200 years, the field of aerobiology has explored the abundance, diversity, survival and transport of micro-organisms in the atmosphere. Micro-organisms have been explored as passive and severely stressed riders of atmospheric transport systems. Recently, an interest in the active roles of these micro-organisms has emerged along with proposals that the atmosphere is a global biome for microbial metabolic activity and perhaps even multiplication. As part of a series of papers on the sources, distribution and roles in atmospheric processes of biological particles in the atmosphere, here we describe the pertinence of questions relating to the potential roles that air-borne micro-organisms might play in meteorological phenomena. For the upcoming era of research on the role of air-borne micro-organisms in meteorological phenomena, one important challenge is to go beyond descriptions of abundance of micro-organisms in the atmosphere toward an understanding of their dynamics in terms of both biological and physico-chemical properties and of the relevant transport processes at different scales. Another challenge is to develop this understanding under contexts pertinent to their potential role in processes related to atmospheric chemistry, the formation of clouds, precipitation and radiative forcing. This will require truly interdisciplinary approaches involving collaborators from the biological and physical sciences, from disciplines as disparate as agronomy, microbial genetics and atmosphere physics, for example
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