2,486 research outputs found
Clinical Ladders in Physical Therapy
The clinical laddering system as it pertains to physical therapy is described. The history, purpose, benefits, and development of clinical ladders is presented. The benefits include improved recruitment and retention of professional physical therapy staff.
A clinical ladder in a physical therapy department may be very beneficial, but the decision to develop it should be considered carefully. Developing a clinical ladder system is a time consuming and costly undertaking and other alternatives should be considered first
A Beam Driven Plasma-Wakefield Linear Collider: From Higgs Factory to Multi-TeV
Plasma wakefield acceleration (PWFA) holds much promise for advancing the
energy frontier because it can potentially provide a 1000-fold or more increase
in acceleration gradient with excellent power efficiency in respect with
standard technologies. Most of the advances in beam-driven plasma wakefield
acceleration were obtained by a UCLA/USC/SLAC collaboration working at the SLAC
FFTB[ ]. These experiments have shown that plasmas can accelerate and focus
both electron and positron high energy beams, and an accelerating gradient in
excess of 50 GeV/m can be sustained in an 85 cm-long plasma. The FFTB
experiments were essentially proof-of-principle experiments that showed the
great potential of plasma accelerators.
The FACET[ ] test facility at SLAC will in the period 2012-2016 further study
several issues that are directly related to the applicability of PWFA to a
high-energy collider, in particular two-beam acceleration where the witness
beam experiences high beam loading (required for high efficiency), small energy
spread and small emittance dilution (required to achieve luminosity).
The PWFA-LC concept presented in this document is an attempt to find the best
design that takes advantage of the PWFA, identify the critical parameters to be
achieved and eventually the necessary R&D to address their feasibility. It best
benefits from the extensive R&D that has been performed for conventional rf
linear colliders during the last twenty years, especially ILC[ ] and CLIC[ ],
with a potential for a comparably lower power consumption and cost.Comment: Submitted to the proceedings of the Snowmass Process CSS2013. Work
supported in part by the U.S. Department of Energy under contract number
DE-AC02-76SF0051
African meningitis belt pneumococcal disease epidemiology indicates a need for an effective serotype 1 containing vaccine, including for older children and adults
<p>Abstract</p> <p>Background</p> <p>Pneumococcal conjugate vaccine strategies in GAVI-eligible countries are focusing on infant immunization but this strategy may not be optimal in all settings. We aimed to collect all available population based data on pneumococcal meningitis throughout life in the African meningitis belt and then to model overall meningitis risk to help inform vaccine policy.</p> <p>Methods</p> <p>After a systematic review of literature published from 1970 through the present, we found robust population-based <it>Streptococcus pneumoniae </it>(Sp) meningitis data across age strata for four African meningitis belt countries that included 35 surveillance years spanning from 1970 to 2005. Using these data we modeled disease risk for a hypothetical cohort of 100,000 persons followed throughout life.</p> <p>Results</p> <p>Similar to meningococcal meningitis, laboratory-confirmed pneumococcal meningitis was seasonal, occurring primarily in the dry season. The mean annual Sp meningitis incidence rates were 98, 7.8 to 14, and 5.8 to 12 per 100,000 among persons <1, 1 through 19, and 20 to 99 years of age, respectively, which (in the absence of major epidemics) were higher than meningococcal meningitis incidences for persons less than 1 and over 20 years of age. Mean Sp meningitis case fatality ratios (CFR) among hospitalized patients ranged from 36-66% depending on the age group, with CFR exceeding 60% for all age groups beyond 40 years; depending on the age group, Sp meningitis mortality incidences were 2 to 12-fold greater than those for meningococcal meningitis. The lifetime risks of pneumococcal meningitis disease and death were 0.6% (1 in 170) and 0.3% (1 in 304), respectively. The incidences of these outcomes were highest among children age <1 year. However, the cumulative risk was highest among persons age 5 to 59 years who experienced 59% of pneumococcal meningitis outcomes. After age 5 years and depending on the country, 59-79% of meningitis cases were caused by serotype 1.</p> <p>Conclusions</p> <p>In the African meningitis belt, Sp is as important a cause of meningitis as <it>Neisseria meningitidis</it>, particularly among older children and working age adults. The meningitis belt population needs an effective serotype 1 containing vaccine and policy discussions should consider vaccine use outside of early childhood.</p
Recommended from our members
A 2CUL Collaborative Ethnographic Assessment of Humanities Doctoral Students: Design, Implementation and Analysis
This paper examines the processes taken to design and administer a collaborative ethnographic study of humanities doctoral students within an inter-institutional, collaborative framework. Project organization and management, including the creation of instruments and analysis of results across two local research teams and institutional cultures is discussed. Effective communications, among and between project teams, and time management were identified as critical factors for success. Benefits resulting from the project included an improved understanding of the needs of a key user group, a heightened interest in user assessment and data-driven decision-making among staff within the partner organizations, and a deeper engagement with academic administrators on both campuses
Recommended from our members
A 2CUL Collaborative Ethnographic Assessment of Humanities Doctoral Students
This paper examines the processes taken to design and administer a collaborative ethnographic study of humanities doctoral students within an inter-institutional, collaborative framework. Project organization and management, including the creation of instruments and analysis of results across two local research teams and institutional cultures is discussed. Effective communications, among and between project teams, and time management were identified as critical factors for success. Benefits resulting from the project included an improved understanding of the needs of a key user group, a heightened interest in user assessment and data-driven decision making among staff within the partner organizations, and a deeper engagement with important academic administrators on both campuses
Recommended from our members
Supporting Humanities Doctoral Student Success: A Collaborative Project between Cornell University Library and Columbia University Libraries
In recent years there have been a number of major, large-scale studies in the United States on the high attrition rates for doctoral students in the humanities. The results of these studies reveal a significant gap between the humanities and other disciplines. None of the studies consulted has specifically considered the role of the library in supporting doctoral program completion, even though it is often characterized as the humanist‘s equivalent to the scientific laboratory. This collaborative study includes focus groups and individual interviews with doctoral students in the humanities at both Cornell and Columbia. The study investigates whether the research library might positively impact doctoral student success in the humanities and discusses specific strategies it might employ to do so
Positron Acceleration in Plasma Wakefields
Plasma acceleration has emerged as a promising technology for future particle
accelerators, particularly linear colliders. Significant progress has been made
in recent decades toward high-efficiency and high-quality acceleration of
electrons in plasmas. However, this progress does not generalize to
acceleration of positrons, as plasmas are inherently charge asymmetric. Here,
we present a comprehensive review of historical and current efforts to
accelerate positrons using plasma wakefields. Proposed schemes that aim to
increase the energy efficiency and beam quality are summarised and
quantitatively compared. A dimensionless metric that scales with the
luminosity-per-beam power is introduced, indicating that positron-acceleration
schemes are currently below the ultimate requirement for colliders. The primary
issue is electron motion; the high mobility of plasma electrons compared to
plasma ions, which leads to non-uniform accelerating and focusing fields that
degrade the beam quality of the positron bunch, particularly for high
efficiency acceleration. Finally, we discuss possible mitigation strategies and
directions for future research.Comment: 24 pages (30 pages with references), 22 figure
Commissioning of the electron injector for the AWAKE experiment
The advanced wakefield experiment (AWAKE) at CERN is the first proton beam-driven plasma wakefield acceleration experiment. The main goal of AWAKE RUN 1 was to demonstrate seeded self-modulation (SSM) of the proton beam and electron witness beam acceleration in the plasma wakefield. For the AWAKE experiment, a 10-meter-long Rubidium-vapor cell together with a high-power laser for ionization was used to generate the plasma. The plasma wakefield is driven by a 400 GeV/c proton beam extracted from the super proton synchrotron (SPS), which undergoes a seeded self-modulation process in the plasma. The electron witness beam used to probe the wakefields is generated from an S-band RF photo-cathode gun and then accelerated by a booster structure up to energies between 16 and 20 MeV. The first run of the AWAKE experiment revealed that the maximum energy gain after the plasma cell is 2 GeV, and the SSM mechanism of the proton beam was verified. In this paper, we will present the details of the AWAKE electron injector. A comparison of the measured electron beam parameters, such as beam size, energy, and normalized emittance, with the simulation results was performed
- …