6,365 research outputs found
A Process for Comparing Dynamics of Distributed Space Systems Simulations
The paper describes a process that was developed for comparing the primary orbital dynamics behavior between space systems distributed simulations. This process is used to characterize and understand the fundamental fidelities and compatibilities of the modeling of orbital dynamics between spacecraft simulations. This is required for high-latency distributed simulations such as NASA s Integrated Mission Simulation and must be understood when reporting results from simulation executions. This paper presents 10 principal comparison tests along with their rationale and examples of the results. The Integrated Mission Simulation (IMSim) (formerly know as the Distributed Space Exploration Simulation (DSES)) is a NASA research and development project focusing on the technologies and processes that are related to the collaborative simulation of complex space systems involved in the exploration of our solar system. Currently, the NASA centers that are actively participating in the IMSim project are the Ames Research Center, the Jet Propulsion Laboratory (JPL), the Johnson Space Center (JSC), the Kennedy Space Center, the Langley Research Center and the Marshall Space Flight Center. In concept, each center participating in IMSim has its own set of simulation models and environment(s). These simulation tools are used to build the various simulation products that are used for scientific investigation, engineering analysis, system design, training, planning, operations and more. Working individually, these production simulations provide important data to various NASA projects
Wormholes and Flux Tubes in 5D Kaluza-Klein Theory
In this paper spherically symmetric solutions to 5D Kaluza-Klein theory, with
``electric'' and/or ``magnetic'' fields are investigated. It is shown that the
global structure of the spacetime depends on the relation between the
``electrical'' and ``magnetic'' Kaluza-Klein fields. For small ``magnetic''
field we find a wormhole-like solution. As the strength of the ``magnetic''
field is increased relative to the strength of the ``electrical'' field, the
wormhole-like solution evolves into a finite or infinite flux tube depending on
the strengths of the two fields. For the large ``electric'' field case we
conjecture that this solution can be considered as the mouth of a wormhole,
with the , and components of the metric acting as
the source of the exotic matter necessary for the formation of the wormhole's
mouth. For the large ``magnetic'' field case a 5D flux tube forms, which is
similar to the flux tube between two monopoles in Type-II superconductors, or
the hypothesized color field flux tube between two quarks in the QCD vacuum.Comment: 12 pages, 5 eps.figures, REVTEX, Discussion about null surfaces
ammended. References added. To be published in PR
Analysis of clogging in constructed wetlands using magnetic resonance
In this work we demonstrate the potential of permanent magnet based magnetic resonance sensors to monitor and assess the extent of pore clogging in water filtration systems. The performance of the sensor was tested on artificially clogged gravel substrates and on gravel bed samples from constructed wetlands used to treat wastewater. Data indicate that the spin lattice relaxation time is linearly related to the hydraulic conductivity in such systems. In addition, within biologically active filters we demonstrate the ability to determine the relative ratio of biomass to abiotic solids, a measurement which is not possible using alternative techniques
Nurses\u27 Alumnae Association Bulletin - Volume 5 Number 8
Calling All Nurses
Financial Report
Calendar of Events
Lest You Forget!
Attention
Review of the Alumnae Association Meetings
President\u27s Report
Barton Memorial Division
Oxygen Therapy
Welcome, White Haven Alumnae
Clinical Use of Penicillin in Infections of the Ears, Nose and Throat
Address - Graduation of Nurses, 1945
Miscellaneous Items
The Blood that Kills
The Story of Malaria
Program
Prizes - May, 1946
Capping Exercises
The Economic Security Program of the Pennsylvania State Nurses\u27 Association
The Clara Melville Scholarship Fund
Card of Thanks
The Poet\u27s Corner
The Hospital Pharmacy
Jefferson Medical College Hospital School of Nursing Faculty
Jefferson Hospital Gray Lady Unite, A.R.R.
The Volunteer Nurses\u27 Aides Salute Jefferson Nurses
Changes in the Staff at Jefferson Hospital
Red Cross Recruits
Did You Know That
The Pennsylvania Nurse
Medical College News
Magazine and Newspaper Items
Central Dressing Room and Transfusion Unit
Rules Concerning Central Dressing Room
Radios and Electrical Appliances
Attending College
Nurses in Anesthesia
Condolences
Marriages
New Arrivals
Deaths
The Bulletin Committee
Attention, Alumnae
New Addresse
Exploring the costs and outcomes of sexually transmitted infection (STI) screening interventions targeting men in football club settings: preliminary cost-consequence analysis of the SPORTSMART pilot randomised controlled trial
Background:
The objective of this study was to compare the costs and outcomes of two sexually transmitted infection (STI) screening interventions targeted at men in football club settings in England, including screening promoted by team captains.
Methods:
A comparison of costs and outcomes was undertaken alongside a pilot cluster randomised control trial involving three trial arms: (1) captain-led and poster STI screening promotion; (2) sexual health advisor-led and poster STI screening promotion and (3) poster-only STI screening promotion (control/comparator). For all study arms, resource use and cost data were collected prospectively.
Results:
There was considerable variation in uptake rates between clubs, but results were broadly comparable across study arms with 50% of men accepting the screening offer in the captain-led arm, 67% in the sexual health advisor-led arm and 61% in the poster-only control arm. The overall costs associated with the intervention arms were similar. The average cost per player tested was comparable, with the average cost per player tested for the captain-led promotion estimated to be £88.99 compared with £88.33 for the sexual health advisor-led promotion and £81.87 for the poster-only (control) arm.
Conclusions:
Costs and outcomes were similar across intervention arms. The target sample size was not achieved, and we found a greater than anticipated variability between clubs in the acceptability of screening, which limited our ability to estimate acceptability for intervention arms. Further evidence is needed about the public health benefits associated with screening interventions in non-clinical settings so that their cost-effectiveness can be fully evaluated
Domestic ventilation rates, indoor humidity and dust mite allergens : are our homes causing the asthma pandemic?
This paper is concerned with historical changes in domestic ventilation rates, relative humidity and the associated risk of house dust mite colonization. A controlled trial evaluated allergen and water vapour control measures on the level of house dust mite (HDM) Der p1 allergen and indoor humidity, concurrently with changes in lung function in 54 subjects who completed the protocol. Mechanical heat recovery ventilation units significantly reduced moisture content in the active group, while HDM allergen reservoirs in carpets and beds were reduced by circa 96%. Self reported health status confirmed a significant clinical improvement in the active group. The study can form the basis for assessing minimum winter ventilation rates that can suppress RH below the critical ambient equilibrium humidity of 60% and thus inhibit dust mite colonization and activity in temperate and maritime in' uenced climatic regions
Activation induced changes in GABA: functional MRS at 7 T with MEGA-sLASER
Functional magnetic resonance spectroscopy (fMRS) has been used to assess the dynamic metabolic responses of the brain to a physiological stimulus non-invasively. However, only limited information on the dynamic functional response of γ-aminobutyric acid (GABA), the primary inhibitory neurotransmitter in the brain, is available. We aimed to measure the activation-induced changes in GABA unambiguously using a spectral editing method, instead of the conventional direct detection techniques used in previous fMRS studies. The Mescher-Garwood-semi-localised by adiabatic selective refocusing (MEGA-sLASER) sequence was developed at 7 T to obtain the time course of GABA concentration without macromolecular contamination. A significant decrease (−12±5%) in the GABA to total creatine ratio (GABA/tCr) was observed in the motor cortex during a period of 10 minutes of hand-clenching, compared to an initial baseline level (GABA/tCr = 0.11±0.02) at rest. An increase in the Glx (glutamate and glutamine) to tCr ratio was also found, which is in agreement with previous findings. In contrast, no significant changes in NAA/tCr and tCr were detected. With consistent and highly efficient editing performance for GABA detection and the advantage of visually identifying GABA resonances in the spectra, MEGA-sLASER is demonstrated to be an effective method for studying of dynamic changes in GABA at 7 T
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