343 research outputs found
Communication in Fluid Medium Using Motor Modulation
Aquatic vehicles may use electric motors for propulsion, such as brushless motors. As an example, a speed of these motors can be controlled using a pulse-width-modulated (PWM) electrical signal that varies the motor speed by varying pulse parameters within the PWM signal. PMW modulation can cause the motor to emit significant acoustic noise into the environment. In a fluid medium, such as aquatic environment, such noise can be detected with hydrophones or other acoustic sensors. The subject matter described herein can include modulating a signal provided to a motor to provide a communication signal to be mechanically (e.g., acoustically) emitted by the motor in a fluid medium, such as an underwater medium. In this manner, the motor can function both as a source of propulsion, and as an electroacoustic transducer (e.g., a transmitter)
Early Surgery for Traumatic Spinal Cord Injury: Where Are We Now?
Study Design: Narrative review.
Objective: There is a strong biological rationale to perform early decompression after traumatic spinal cord injury (SCI). With an enlarging clinical evidence base, most spine surgeons internationally now favor early decompression for the majority of SCI patients; however, a number of pertinent questions remain surrounding this therapy.
Methods: A narrative review evaluating the status of early surgery for SCI. In particular, we addressed the following questions: (1) Which patients stand to benefit most from early surgery? 2) What is the most appropriate time threshold defining early surgery?
Results: Although heterogeneity exists, the evidence generally seems to support early surgery. While the best evidence exists for cervical SCI, there is insufficient data to support a differential effect for early surgery depending on neurological level or injury severity. When comparing thresholds to define early versus late surgery-including a later threshold (48-72 hours), an earlier threshold (24 hours), and an ultra-early threshold (8-12 hours)-the 2 earlier time points seem to be associated with the greatest potential for improved outcomes. However, existing prehospital and hospital logistics pose barriers to early surgery in a significant proportion of patients. An overview of recommendations from the recent AOSpine guidelines is provided.
Conclusion: In spite of increasing acceptance of early surgery post SCI, further research is needed to (1) identify subgroups of patients who stand to derive particular benefit-in particular to develop more evidence-based approaches for central cord syndrome and (2) investigate the efficacy and feasibility of ultra-early surgery targeting more aggressive timelines
Probabilistic Analysis and Design of a Raked Wing Tip for a Commercial Transport
An approach for conducting reliability-based design and optimization (RBDO) of a Boeing 767 raked wing tip (RWT) is presented. The goal is to evaluate the benefits of RBDO for design of an aircraft substructure. A finite-element (FE) model that includes eight critical static load cases is used to evaluate the response of the wing tip. Thirteen design variables that describe the thickness of the composite skins and stiffeners are selected to minimize the weight of the wing tip. A strain-based margin of safety is used to evaluate the performance of the structure. The randomness in the load scale factor and in the strain limits is considered. Of the 13 variables, the wing-tip design was controlled primarily by the thickness of the thickest plies in the upper skins. The report includes an analysis of the optimization results and recommendations for future reliability-based studies
Projeto Historiadores do Futuro: a história mora ao lado!
Anais do 35º Seminário de Extensão Universitária da Região Sul - Área temática: Cultura – Patrimônio cultural, histórico e naturalO projeto de extensão Historiadores do Futuro: a história mora ao lado
objetiva proporcionar aos estudantes do Campus Pinhais-IFPR a experiência do
fazer historiográfico, tendo como objeto de investigação a história do bairro Vila
Amélia, localizado no município de Pinhais-PR. A partir do uso da metodologia da
história oral e da prática da análise do conteúdo problematizamos as fontes
históricas colhidas e organizamos uma exposição histórica sobre a localidade
envolvendo a participação da comunidade local e dos estudantes do campus
Pinhais-IFPR resultando na valorização da história local e no reconhecimento do
valor social do conhecimento históric
Efficacy and safety of methylprednisolone sodium succinate in acute spinal cord injury: a systematic review
Study Design: Systematic review and meta-analysis. Objective: The objective of this study was to conduct a systematic review to assess the comparative effectiveness and safety of high-dose methylprednisolone sodium succinate (MPSS) versus no pharmacological treatment in patients with traumatic spinal cord injury (SCI). Methods: A systematic search was performed in PubMed and the Cochrane Collaboration Library for literature published between January 1956 and June 17, 2015. Included studies ere critically appraised, and Grades of Recommendation Assessment, Development and Evaluation methods were used to determine the overall quality of evidence for primary outcomes. Previous systematic reviews on this topic were collated and evaluated using the Assessment of Multiple Systematic Reviews scoring system. Results: The search yielded 723 citations, 13 of which satisfied inclusion criteria. Among these, 6 were primary research articles and 7 were previous systematic reviews. Based on the included research articles, there was moderate evidence that the 24-hour NASCIS II (National Acute Spinal Cord Injury Studies) MPSS regimen has no impact on long-term neurological recovery when all postinjury time points are considered. However, there is also moderate evidence that subjects receiving the same MPSS regimen within 8 hours of injury achieve an additional 3.2 points (95% confidence interval = 0.10 to 6.33; P = .04) of motor recovery compared with patients receiving placebo or no treatment. Conclusion: Although safe to administer, a 24-hour NASCIS II MPSS regimen, when all postinjury time points are considered, has no impact on indices of long-term neurological recovery. When commenced within 8 hours of injury, however, a high-dose 24-hour regimen of MPSS confers a small positive benefit on long-term motor recovery and should be considered a treatment option for patients with SCI
Recommended from our members
Recovery priorities in degenerative cervical myelopathy: a cross-sectional survey of an international, online community of patients.
OBJECTIVES: To establish the recovery priorities of individuals suffering with degenerative cervical myelopathy (DCM). DESIGN: A cross-sectional, observational study. SETTING: Patients from across the world with a diagnosis of DCM accessed the survey over an 18-month period on Myelopathy.org, an international myelopathy charity. PARTICIPANTS: 481 individuals suffering from DCM completed the online survey fully. MAIN OUTCOME MEASURES: Functional recovery domains were established through qualitative interviews and a consensus process. Individuals were asked about their disease characteristics, including limb pain (Visual Analogue Scale) and functional disability (patient-derived version of the modified Japanese Orthopaedic Association score). Individuals ranked recovery domains (arm and hand function, walking, upper body/trunk function, sexual function, elimination of pain, sensation and bladder/bowel function) in order of priority. Priorities were analysed as the modal first priority and mean ranking. The influence of demographics on selection was analysed, with significance p<0.05. RESULTS: Of 659 survey responses obtained, 481 were complete. Overall, pain was the most popular recovery priority (39.9%) of respondents, followed by walking (20.2%), sensation (11.9%) and arm and hand function (11.5%). Sexual function (5.7%), bladder and bowel (3.7%) and trunk function (3.5%) were chosen less frequently. When considering the average ranking of symptoms, while pain remained the priority (2.6±2.0), this was closely followed by walking (2.9±1.7) and arm/hand function (3.0±1.4). Sensation ranked lower (4.3±2.1). With respect to disease characteristics, overall pain remained the recovery priority, with the exception of patients with greater walking impairment (p<0.005) who prioritised walking, even among patients with lower pain scores. CONCLUSIONS: This is the first study investigating patient priorities in DCM. The patient priorities reported provide an important framework for future research and will help to ensure that it is aligned with patient needs.NIHR
Welcome Trus
Optimal search strategies for detecting cost and economic studies in EMBASE
BACKGROUND: Economic evaluations in the medical literature compare competing diagnosis or treatment methods for their use of resources and their expected outcomes. The best evidence currently available from research regarding both cost and economic comparisons will continue to expand as this type of information becomes more important in today's clinical practice. Researchers and clinicians need quick, reliable ways to access this information. A key source of this type of information is large bibliographic databases such as EMBASE. The objective of this study was to develop search strategies that optimize the retrieval of health costs and economics studies from EMBASE. METHODS: We conducted an analytic survey, comparing hand searches of journals with retrievals from EMBASE for candidate search terms and combinations. 6 research assistants read all issues of 55 journals indexed by EMBASE for the publishing year 2000. We rated all articles using purpose and quality indicators and categorized them into clinically relevant original studies, review articles, general papers, or case reports. The original and review articles were then categorized for purpose (i.e., cost and economics and other clinical topics) and depending on the purpose as 'pass' or 'fail' for methodologic rigor. Candidate search strategies were developed for economic and cost studies, then run in the 55 EMBASE journals, the retrievals being compared with the hand search data. The sensitivity, specificity, precision, and accuracy of the search strategies were calculated. RESULTS: Combinations of search terms for detecting both cost and economic studies attained levels of 100% sensitivity with specificity levels of 92.9% and 92.3% respectively. When maximizing for both sensitivity and specificity, the combination of terms for detecting cost studies (sensitivity) increased 2.2% over the single term but at a slight decrease in specificity of 0.9%. The maximized combination of terms for economic studies saw no change in sensitivity from the single term and only a 0.1% increase in specificity. CONCLUSION: Selected terms have excellent performance in the retrieval of studies of health costs and economics from EMBASE
Recommended from our members
Detection of Nucleocapsid Antibodies Associated with Primary SARS-CoV-2 Infection in Unvaccinated and Vaccinated Blood Donors.
Nucleocapsid antibody assays can be used to estimate SARS-CoV-2 infection prevalence in regions implementing spike-based COVID-19 vaccines. However, poor sensitivity of nucleocapsid antibody assays in detecting infection after vaccination has been reported. We derived a lower cutoff for identifying previous infections in a large blood donor cohort (N = 142,599) by using the Ortho VITROS Anti-SARS-CoV-2 Total-N Antibody assay, improving sensitivity while maintaining specificity >98%. We validated sensitivity in samples donated after self-reported swab-confirmed infections diagnoses. Sensitivity for first infections in unvaccinated donors was 98.1% (95% CI 98.0-98.2) and for infection after vaccination was 95.6% (95% CI 95.6-95.7) based on the standard cutoff. Regression analysis showed sensitivity was reduced in the Delta compared with Omicron period, in older donors, in asymptomatic infections, <30 days after infection, and for infection after vaccination. The standard Ortho N antibody threshold demonstrated good sensitivity, which was modestly improved with the revised cutoff
- …