202 research outputs found
Zystische Adventitiadegeneration (CAD) als Ursache einer invalidisierenden Claudicatio intermittens
Zusammenfassung: Bei einem 45-jährigen Patienten mit wechselhaften Ischämiebeschwerden und initial limitierter Gehstrecke rechts von höchstens 50m führten die duplexsonographischen und angiographischen Abklärungen zur Verdachtsdiagnose einer zystischen Adventitiadegeneration. Intraoperativ zeigte sich ein zystisch aufgetriebenes Poplitealsegment mit Entleerung von gallertiger Flüssigkeit. Aufgrund der langstreckigen Veränderung erfolgte die Segmentresektion der A.poplitea und Rekonstruktion mittels eines autologen Veneninterponats. Die CAD ist ein seltenes Krankheitsbild, an das gerade bei jungen Patienten ohne systemische Arteriosklerose gedacht werden sollte. Die Therapie ist je nach Fall chirurgisch erhaltend durch Zystenresektion mittels "Exarterektomie" oder gefäßresezierend, insbesondere bei langstreckigen Veränderungen bzw. vollständiger Okklusion mittels Ersatz durch ein Veneninterpona
Personal experience with whole-body, low-dosage, digital X-ray scanning (LODOX-Statscan) in trauma
<p>Abstract</p> <p>Background</p> <p>Lodox-Statscan is a whole-body, skeletal and soft-tissue, low-dose X-ray scanner Anterior-posterior and lateral thoraco-abdominal studies are obtained in 3-5 minutes with only about one-third of the radiation required for conventional radiography. Since its approval by the Food and Drug Administration (FDA) in the USA, several trauma centers have incorporated this technology into their Advanced Trauma Life Support protocols. This review provides a brief overview of the system, and describes the authors' own experience with the system.</p> <p>Methods</p> <p>We performed a PubMed search to retrieve all references with 'Lodox' and 'Stat-scan' used as search terms. We furthermore used the google search engine to identify existing alternatives. To the best of our knowledge, this is the only FDA-approved device of its kind currently used in trauma.</p> <p>Results and Conclusion</p> <p>The intention of our review has been to sensitize the readership that such alternative devices exist. The key message is that low dosage full body radiography may be an alternative to conventional resuscitation room radiography which is usually a prelude to CT scanning (ATLS algorithm). The combination of both is radiation intensive and therefore we consider any reduction of radiation a success. But only the future will show whether LS will survive in the face of low-dose radiation CT scanners and magnetic resonance imaging devices that may eventually completely replace conventional radiography.</p
Finding and Navigating to Household Objects with UHF RFID Tags by Optimizing RF Signal Strength
©2014 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Presented at the IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS 2014), 14-18 September 2014, Chicago, IL.DOI: 10.1109/IROS.2014.6942914We address the challenge of finding and navigating
to an object with an attached ultra-high frequency radio-
frequency identification (UHF RFID) tag. With current off-the-
shelf technology, one can affix inexpensive self-adhesive UHF
RFID tags to hundreds of objects, thereby enabling a robot
to sense the RF signal strength it receives from each uniquely
identified object. The received signal strength indicator (RSSI)
associated with a tagged object varies widely and depends
on many factors, including the object’s pose, material prop-
erties and surroundings. This complexity creates challenges for
methods that attempt to explicitly estimate the object’s pose.
We present an alternative approach that formulates finding
and navigating to a tagged object as an optimization problem
where the robot must find a pose of a directional antenna
that maximizes the RSSI associated with the target tag. We
then present three autonomous robot behaviors that together
perform this optimization by combining global and local search.
The first behavior uses sparse sampling of RSSI across the
entire environment to move the robot to a location near the
tag; the second samples RSSI over orientation to point the robot
toward the tag; and the third samples RSSI from two antennas
pointing in different directions to enable the robot to approach
the tag. We justify our formulation using the radar equation
and associated literature. We also demonstrate that it has good
performance in practice via tests with a PR2 robot from Willow
Garage in a house with a variety of tagged household objects
The efficiency of full body radiography ‘Lodox Statscan’ in the detection of peripheral skeletal fractures in adult trauma patients
Cost-effectiveness of Physical Therapy vs Intra-articular Glucocorticoid Injection for Knee Osteoarthritis: A Secondary Analysis From a Randomized Clinical Trial
Importance: Physical therapy and glucocorticoid injections are initial treatment options for knee osteoarthritis, but available data indicate that most patients receive one or the other, suggesting they may be competing interventions. The initial cost difference for treatment can be substantial, with physical therapy often being more expensive at the outset, and cost-effectiveness analysis can aid patients and clinicians in making decisions.
Objective: To investigate the incremental cost-effectiveness between physical therapy and intra-articular glucocorticoid injection as initial treatment strategies for knee osteoarthritis.
Design, setting, and participants: This economic evaluation is a secondary analysis of a randomized clinical trial performed from October 1, 2012, to May 4, 2017. Health economists were blinded to study outcomes and treatment allocation. A randomized sample of patients seen in primary care and physical therapy clinics with a radiographically confirmed diagnosis of knee osteoarthritis were evaluated from the clinical trial with 96.2% follow-up at 1 year.
Interventions: Physical therapy or glucocorticoid injection.
Main outcomes and measures: The main outcome was incremental cost-effectiveness between 2 alternative treatments. Acceptability curves of bootstrapped incremental cost-effectiveness ratios (ICERs) were used to identify the proportion of ICERs under the specific willingness-to-pay level (100 000). Health care system costs (total and knee related) and health-related quality-of-life based on quality-adjusted life-years (QALYs) were obtained.
Results: A total of 156 participants (mean [SD] age, 56.1 [8.7] years; 81 [51.9%] male) were randomized 1:1 and followed up for 1 year. Mean (SD) 1-year knee-related medical costs were 4224) in the glucocorticoid injection group and 1015) in the physical therapy group. The mean difference in QALY significantly favored physical therapy at 1 year (0.076; 95% CI, 0.02-0.126; P = .003). Physical therapy was the more cost-effective intervention, with an ICER of 100 000.
Conclusions and relevance: A course of physical therapy was cost-effective compared with a course of glucocorticoid injections for patients with knee osteoarthritis. These results suggest that, although the initial cost of delivering physical therapy may be higher than an initial course of glucocorticoid injections, 1-year total knee-related costs are equivalent, and greater improvement in QALYs may justify the initial higher costs.
Trial registration: ClinicalTrials.gov Identifier: NCT0142715
RFID-Guided Robots for Pervasive Automation
©2010 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.DOI: 10.1109/MPRV.2010.17Passive UHF RFID tags are well matched to robots' needs. Unlike lowfrequency (LF) and high-frequency (HF) RFID tags, passive UHF RFID tags are readable from across a room, enabling a mobile robot to efficiently discover and locate them. Using tags' unique IDs, a semantic database, and RF perception via actuated antennas, this paper shows how a robot can reliably interact with people and manipulate labeled objects
Susceptible host availability modulates climate effects on dengue dynamics
Experiments and models suggest that climate affects mosquito-borne disease transmission. However, disease transmission involves complex nonlinear interactions between climate and population dynamics, which makes detecting climate drivers at the population level challenging. By analysing incidence data, estimated susceptible population size, and climate data with methods based on nonlinear time series analysis (collectively referred to as empirical dynamic modelling), we identified drivers and their interactive effects on dengue dynamics in San Juan, Puerto Rico. Climatic forcing arose only when susceptible availability was high: temperature and rainfall had net positive and negative effects respectively. By capturing mechanistic, nonlinear and context-dependent effects of population susceptibility, temperature and rainfall on dengue transmission empirically, our model improves forecast skill over recent, state-of-the-art models for dengue incidence. Together, these results provide empirical evidence that the interdependence of host population susceptibility and climate drives dengue dynamics in a nonlinear and complex, yet predictable way.R35GM133439 - NIH HHS; DBI-1667584 - National Science Foundation; DEB-1655203 - National Science Foundation; 00028335 - Lenfest Foundation; Stanford University: Bing Fellowship in Honor of Paul Ehrlich, Stanford Data Science Scholars program, Lindsay Family E-IPER Fellowship, Illich-Sadowsky Interdisciplinary Graduate Fellowship, Terman Fellowship, King Center for Global Development seed grant; SERDP 15 RC-2509 - U.S. Department of Defense; University of California San Diego: McQuown Chair in Natural Sciences; DBI-1611767 - National Science Foundation; RAPID DEB-1640780 - National Science Foundation; R35GM133439 - NIH HHS; Hellman Foundation: Hellman Faculty Fellowship; Stanford Woods Institute for the Environment: Environmental Ventures Program; DEB-1518681 - National Science Foundation; R35 GM133439 - NIGMS NIH HHS; DEB-2011147 - National Science Foundationhttps://www.biorxiv.org/content/biorxiv/early/2020/10/19/2019.12.20.883363.full.pdfAccepted manuscrip
Generalized Theorems for Nonlinear State Space Reconstruction
Takens' theorem (1981) shows how lagged variables of a single time series can be used as proxy variables to reconstruct an attractor for an underlying dynamic process. State space reconstruction (SSR) from single time series has been a powerful approach for the analysis of the complex, non-linear systems that appear ubiquitous in the natural and human world. The main shortcoming of these methods is the phenomenological nature of attractor reconstructions. Moreover, applied studies show that these single time series reconstructions can often be improved ad hoc by including multiple dynamically coupled time series in the reconstructions, to provide a more mechanistic model. Here we provide three analytical proofs that add to the growing literature to generalize Takens' work and that demonstrate how multiple time series can be used in attractor reconstructions. These expanded results (Takens' theorem is a special case) apply to a wide variety of natural systems having parallel time series observations for variables believed to be related to the same dynamic manifold. The potential information leverage provided by multiple embeddings created from different combinations of variables (and their lags) can pave the way for new applied techniques to exploit the time-limited, but parallel observations of natural systems, such as coupled ecological systems, geophysical systems, and financial systems. This paper aims to justify and help open this potential growth area for SSR applications in the natural sciences
- …