Browsing by Type "Other article"

Now showing 1 - 20 of 555

Open Access
9/11 Museum Should Not Conflate Islam and Terrorism
(Huffington Post, 2014-05-15) Schanzer, DH
Open Access
A BENCH-TOP PROTOTYPE OF A VARIABLE STIFFNESS PROSTHESIS
(2005) Russell, D.; McTavish, M.
A prototype of a variable stiffness prosthetic joint has been constructed and tested. The joint is based on two actuator subsystems arranged in an antagonistic configuration. Each actuator subsystem is composed of a small, high-speed electric motor, a single stage, worm-gear based transmission and a nonlinear stiffness element. Each nonlinear stiffness element is composed of a set of short sections of elastic tube that was chosen based on its stiffness characteristics. The system is powered by batteries and can be controlled in a number of ways. The paper will present the basis used for selecting the nonlinear stiffness elements, the details of the design as constructed and a comparison of the actual performance of the prototype to predictions based on design calculations and simulations. The prototype has performance that is comparable to commercially available prostheses and showed good correspondence between simulation and prototype. The prototype was able to lift a 2 kg load through 135 degrees in 1.42 seconds and to vary its stiffness from 14 to 24 Nm/rad.
Open Access
A Brief History of BioPerl
(2016-03-08) Crossman, Colin; Rai, Arti K.
Large-scale open-source projects face a litany of pitfalls and difficulties. Problems of contribution quality, credit for contributions, project coordination, funding, and mission-creep are ever-present. Of these, long-term funding and project coordination can interact to form a particularly difficult problem for open-source projects in an academic environment. BioPerl was chosen as an example of a successful academic open-source project. Several of the roadblocks and hurdles encountered and overcome in the development of BioPerl are examined through the telling of the history of the project. Along the way, key points of open-source law are explained, such as license choice and copyright. The BioPerl project current status is then analyzed, and four different strategies typically employed by traditional open-source projects at this stage are analyzed as future directions. Strategies such as soliciting donations, securing grants, providing dual-licenses to enhance commercial interest, and the paid provision of support have all been employed in various traditional open-source projects with success, but each has drawbacks when applied to the academy. Finally, the construction of a successful long-term strategy for BioPerl, and other academic open-source projects, is proposed so that such projects can navigate the difficulties.
Open Access
A BUS PROTOCOL FOR INTERCOMPONENT COMMUNICATION IN ADVANCED UPPER-LIMB PROSTHESES
(2005) Stavdahl, Oyvind; Mathisen, Geir
Microcontrollers are ubiquitous in modern electronic products, powered prosthetic components being no exception. Likewise, digital communication buses are the key technology for interconnecting such smart devices for reasons such as reduced wiring requirements, high information throughput, robustness in the presence of noise and flexibility. This flexibility contains the potential of interoperability, which means that similar components from different manufacturers may communicate in the same way so that one can easily be replaced by another or components from different manufacturers can be combined in one and the same system. However desirable this situation is, it requires an open, sandardised communication protocol that is adhered to by the majority of the manufacturers and research organisations. Presently no such standard exists in the prosthetics industry, while it has existed in related fields such as wheelchairs and environmental controllers for a number of years. In this paper we propose such a bus standard, and outline the potential benefits for end users, prosthetists and technicians, healthcare providers, manufacturers and researchers. We then list several important aspects of a prosthesis bus that must be carefully considered, and invite interested parties to engage in the completion of a draft specification.
Open Access
A Case for Quantifying Statistical Robustness of Specialized Probabilistic AI Accelerators
(2019 IBM IEEE CAS/EDS – AI Compute Symposium, 2019-10-02) Zhang, Xiangyu; Mukherjee, Sayan; Lebeck, Alvin
Open Access
A Christmas Story -Septic Tank Drowning/Aspiration
(Case Studies in Emergency Medicine) Severance, Harry
Open Access
A Common Stage: Theater and Public Life in Medieval Arras
(2010) Solterer, Helen
Open Access
A Comparison of Surface and Internally Measured Myoelectric Signals for use in Prosthetic Control
(2005) Hargrove, L.; Hudgins, B.; Englehart, K.; Leckey, R.
The surface myoelectric signal (MES) has proven to be an effective control input for powered prostheses. Pattern recognition based controllers use multi-channel surface MES as inputs to discriminate between the desired classes of limb activation. There are two major methods which may be pursued to increase the accuracy of the controller: 1) use signal processing to extract more information from the input signals; or 2) provide more informative raw signals to the controller. As a result of recent technological advances, it is reasonable to assume that there will soon be implantable myoelectric sensors which will enable the internal MES to be used as inputs to controllers [1]. An internal MES measurement should have less muscular crosstalk allowing for more independent control sites. However, it remains unclear if this benefit outweighs the loss of the more global information contained in the surface MES. This study compares the classification accuracy of several pattern based myoelectric controllers which use information extracted from surface MES to the same controllers which use information extracted from fine-wire intramuscular MES.
Open Access
A Comparison of the Wellbeing of Orphans and Abandoned Children Ages 6-12 in Institutional and Community-Based Care Settings in 5 Less Wealthy Nations
(2009) Whetten, Kathryn; Ostermann, Jan; Whetten, Rachel A; Pence, Brian W; O'Donnell, Karen; Messer, Lynne C; Thielman, Nathan M; Positive Outcomes for Orphans (POFO) Research Team
Background: Leaders are struggling to care for the estimated 143,000,000 orphans and millions more abandoned children worldwide. Global policy makers are advocating that institution-living orphans and abandoned children (OAC) be moved as quickly as possible to a residential family setting and that institutional care be used as a last resort. This analysis tests the hypothesis that institutional care for OAC aged 6-12 is associated with worse health and wellbeing than community residential care using conservative two-tail tests. Methodology: The Positive Outcomes for Orphans (POFO) study employed two-stage random sampling survey methodology in 6 sites across 5 countries to identify 1,357 institution-living and 1,480 community-living OAC ages 6-12, 658 of whom were double-orphans or abandoned by both biological parents. Survey analytic techniques were used to compare cognitive functioning, emotion, behavior, physical health, and growth. Linear mixed-effects models were used to estimate the proportion of variability in child outcomes attributable to the study site, care setting, and child levels and institutional versus community care settings. Conservative analyses limited the community living children to double-orphans or abandoned children. Principal Findings: Health, emotional and cognitive functioning, and physical growth were no worse for institution-living than community-living OAC, and generally better than for community-living OAC cared for by persons other than a biological parent. Differences between study sites explained 2-23% of the total variability in child outcomes, while differences between care settings within sites explained 8-21%. Differences among children within care settings explained 64-87%. After adjusting for sites, age, and gender, institution vs. community-living explained only 0.3-7% of the variability in child outcomes. Conclusion: This study does not support the hypothesis that institutional care is systematically associated with poorer wellbeing than community care for OAC aged 6-12 in those countries facing the greatest OAC burden. Much greater variability among children within care settings was observed than among care settings type. Methodologically rigorous studies must be conducted in those countries facing the new OAC epidemic in order to understand which characteristics of care promote child wellbeing. Such characteristics may transcend the structural definitions of institutions or family homes.
Open Access
A COMPARISON OF UPPER LIMB AMPUTEES AND PATIENTS WITH UPPER LIMB INJURIES USING THE DISABILITY OF THE ARM, SHOULDER AND HAND (DASH).
(2005) Davidson, Judith
Amputation of a limb represents a catastrophe for the adult amputee and their family. However data regarding the prosthetic, functional and psychological outcomes achieved by these patients is limited. There is no well recognised outcome measure used throughout Australia, UK or America especially for aquired adult amputations of the upper limb. Most scales currently in use fail to identify the psychological adjustment problems which many of these amputees demonstrate. Many adult amputees continue to report significant behavioural limitations and discomfort, associated with low self-esteem, anxiety and depression when compared with an able-bodied control sample.(1) Phantom limb phenomena is also a well recognised problem for many upper limb amputees . Scales used to measure prosthetic use rarely investigate the impact pain has on the amputee and his or her well being. The Disability of the Arm Shoulder and Hand Scale (DASH) is an evaluative outcome measure for patients with upper extremity musculoskeletal conditions designed in the mid 1990s by the American Academy of Orthopaedic Surgeons and Toronto Institute for Work and Health. (2,3,4) It is a region specific questionnaire as opposed to diagnosis specific questionnaire. It measures function & symptoms of musculo-skeletal disorders in upper limb. The DASH was able to demonstrate change in all situations in which change was presumed to have occurred. The DASH was found to have comparable responsiveness to the joint specific measures. It demonstrated suitable levels of sensitivity and specificity.
Open Access
A COMPENSATING SHOULDER JOINT TO ASSIST THE SHORT TRANSHUMERAL AMPUTEE
(2008) Williams, T. Walley, III
The typical problem patient has a transhumeral amputation 30 to 60 mm below the axilla. No matter how well the socket is made, the moment arm in the socket is too little to sustain the four foot-pound torque of a typical advanced prosthesis when working out in front. Matters get worse if the prosthetic terminal device carries a load. A prosthesis that solves this problem must compensate for the gravitational torque generated by the prosthesis itself so that all user generated torque can be used to position the prosthesis and to support the terminal device load
Open Access
A computational screen for site selective A-to-I editing detects novel sites in neuron specific Hu proteins
(2010) Ensterö, Mats; Akerborg, Orjan; Lundin, Daniel; Wang, Bei; Furey, Terrence S; Ohman, Marie; Lagergren, Jens
Background: Several bioinformatic approaches have previously been used to find novel sites of ADAR mediated A-to-I RNA editing in human. These studies have discovered thousands of genes that are hyper-edited in their non-coding intronic regions, especially in alu retrotransposable elements, but very few substrates that are site-selectively edited in coding regions. Known RNA edited substrates suggest, however, that site selective A-to-I editing is particularly important for normal brain development in mammals. Results: We have compiled a screen that enables the identification of new sites of site-selective editing, primarily in coding sequences. To avoid hyper-edited repeat regions, we applied our screen to the alu-free mouse genome. Focusing on the mouse also facilitated better experimental verification. To identify candidate sites of RNA editing, we first performed an explorative screen based on RNA structure and genomic sequence conservation. We further evaluated the results of the explorative screen by determining which transcripts were enriched for A-G mismatches between the genomic template and the expressed sequence since the editing product, inosine (I), is read as guanosine (G) by the translational machinery. For expressed sequences, we only considered coding regions to focus entirely on re-coding events. Lastly, we refined the results from the explorative screen using a novel scoring scheme based on characteristics for known A-to-I edited sites. The extent of editing in the final candidate genes was verified using total RNA from mouse brain and 454 sequencing. Conclusions: Using this method, we identified and confirmed efficient editing at one site in the Gabra3 gene. Editing was also verified at several other novel sites within candidates predicted to be edited. Five of these sites are situated in genes coding for the neuron-specific RNA binding proteins HuB and HuD.
Open Access
A Delegation-Based Theory of Expertise
(American Economic Journal: Microeconomics, 2021-11-01) Ambrus, Attila; Baranovskyi, Volodymyr; Kolb, Aaron
We investigate information aggregation and competition in a delegation framework. An uninformed principal is unable to perform a task herself and must choose between one of two biased and imperfectly informed experts. In the focal equilibrium, experts exaggerate their biases, anticipating an ideological winner's curse. We show that having a second expert can benefit the principal, even when equally or more biased than the first expert. The principal can benefit from commitment to an "element of surprise" and prefers experts with equal rather than opposite biases.
Open Access
A FLEXIBLE USER INTERFACE FOR RAPID PROTOTYPING OF ADVANCED REAL-TIME MYOELECTRIC CONTROL SCHEMES
(2008) Scheme, Erik; Englehart, Kevin
A recent emphasis on the advancement of upper limb prosthetics, due in part to the high number of injuries resulting from ongoing military conflicts, has accelerated research in the field of advanced prosthetics. One important aspect of the controls portion of this research is the ability to quickly transition from experimental algorithms to control schemes which can be used and tested in real time by end users. Herein, the authors introduce a powerful Matlab-based software package which facilitates rapid prototyping and testing of novel real-time control schemes. The ACE (Acquisition and Control Environment) application has recently been used as a research and clinical tool, helping to verify the viability of existing myoelectric control strategies, and is helping to accelerate the development of novel control schemes.
Open Access
A Generalizable Scale of Propensity to Plan: The Long and the Short of Planning for Time and for Money
(2010) Lynch, John G; Netemeyer, Richard G; Spiller, Stephen A; Zammit, Alessandra
Planning has pronounced effects on consumer behavior and intertemporal choice. We develop a six-item scale measuring individual differences in propensity to plan that can be adapted to different domains and used to compare planning across domains and time horizons. Adaptations tailored to planning time and money in the short run and long run each show strong evidence of reliability and validity. We find that propensity to plan is moderately domain-specific. Scale measures and actual planning measures show that for time, people plan much more for the short run than the long run; for money, short- and long-run planning differ less. Time and money adaptations of our scale exhibit sharp differences in nomological correlates; short- run and long-run adaptations differ less. Domain-specific adaptations predict frequency of actual planning in their respective domains. A "very long-run" money adaptation predicts FICO credit scores; low planners thus face materially higher cost of credit.
Open Access
A Guide to Municipal Water Conservation Pricing in Utah
(Utah State University Extension Fact Sheet, 2019-01-01) Sutherland, Sara; Edwards, Eric
Open Access
A Man with No Religion
(2012-02-06) Strandberg, Victor
Open Access
A MINIMAL JERK PROSTHESIS CONTROL SYSTEM
(2005) Hill, Stewart Scotland; Binnie, T.D.; Gow, T.J.
Efficient prosthesis control is dependant on the user’s ability to control the desired movements of the prosthesis. Observed manifestations of jerk on a complete arm prosthesis can lead to difficulty in performing controlled movements, especially under load on gravity assisted downward movements. The application of so called soft start and soft stop routines for controlling the velocity profile of the prosthesis joint through its rotational movement can go some way to reducing this effect. It is proposed that an adaptive velocity control system can be applied to the same prosthesis under the same test conditions and reduce the discernible jerk considerably. This adaptive system monitors the change is angular velocity thus controlling the second and third derivatives of position. The implication of actively controlled angular velocity lends itself to minimize jerk, combined with reduced power consumption, and an increase in parts life and reliability. This control is applicable to all externally powered prosthetic limbs, regardless of user interface.
Open Access
A modular simulation system for the bidomain equations
Pormann, J
Cardiac arrhythmias and fibrillation are potentially life threatening diseases that can result from the improper conduction of electrical impulses in the heart. Experimental study of such cardiac abnormalities are dangerous at best, often requiring the subject to be placed in fibrillation for some time before attempting a large ``rescue'' shock. Thus, most all studies are done in animals and not humans. Furthermore, there is some indication that heart size may have considerable implications for fibrillation and other conduction abnormalities. Thus animal models for defibrillation studies must be chosen with great care. As an alternative, researchers are now using computer simulation to study the factors that generate and sustain arrhythmias, hoping to obtain at least preliminary data to guide fewer, more targeted experimental studies. Computer simulations of the Bidomain Equations have become very complex as they have been applied to many problems in cardiac electrophysiology. More complex membrane dynamics, irregular grids, and 3-D data sets are all being investigated. Software engineering principles will need to be applied to manage this continuing growth in complexity. We propose a modular framework for development of a Simulation System whereby a researcher may mix and match program elements to generate a simulator tailored to their particular problem. The modular approach will simplify the generation and maintenance of the different program elements and it will enable the end-researcher to determine the proper mix of complexity versus speed for their particular problem of interest. The contrary approach, one monolithic program which can run all simulations of all complexities, is simply unrealistic. It would impose too great a burden on maintenance and upgradability, and it would be difficult to provide good performance for a wide range of applications. The modular approach also allows for the incremental inclusion of various complexities in the bidomain model. From a simple 2-D homogeneous, isotropic regular grid, monodomain simulation, we can progress, step by step, to a bidomain simulation with a fully implicit time-integration scheme on irregular, 3-D grids with arbitrary anisotropy and inhomogeneity, with a non-trivial membrane model. Simulations with such a wealth of complexity have not been performed to date. As microprocessors have become cheaper and more powerful, parallel computing has become more widespread. Machines with hundreds of high-performance CPUs connected by fast networks are commonplace and are now capable of surpassing traditional vector-based supercomputers in terms of overall performance. The Simulation System presented here incorporates data-parallelism to allow large scale Bidomain problems to be run on these newest parallel supercomputers. The large amount of distributed memory in such machines can be harnessed to allow extremely large scale simulations to be run. The large number of CPUs provide a tremendous amount of computational power which can be used to run such simulations more quickly. Finally, the results presented here show that a modular Simulation System is feasible for a wide range of pplications, and that it can obtain very good performance over this range of applications. The parallel speed-up seen was very good, regularly achieving a factor of 13 speed-up on 16 processors. The results presented here also show that we can simulate bidomain problems using an implicit time-integrator with an irregular, anisotropic and inhomogeneous, grid and a non-trivial membrane model. We are able to run such simulations on parallel computers, thereby harnessing a tremendous amount of memory and computational resources. Such simulations have not been run to date.
Open Access
A MYOELECTRICALLY CONTROLLED PROSTHETIC HAND FOR TRANSMETACARPAL AMPUTATIONS.
(2002) Weir, Richard F.; Grahn, Edward C.
We have developed a new externally-powered, myoelectrically controlled partial hand prosthesis that is suitable for fitting those persons with amputations at or more proximal to the level of the metacarpophalangeal (MCP) joint. This hand mechanism is capable of reasonable pinch forces (12 lbsf) and fast opening and closing (2 rads/sec). In a partial hand mechanism there is very little space available for the drive mechanism if an aesthetic result is to be achieved and any residual motion of the wrist is to be preserved. The challenge is to be able to fit all the requisite mechanisms and electronics in the highly confined volume that remains after accommodating the residual limb and still have reasonable performance.

Browsing by Type "Other article"

Results Per Page

Sort Options