6,662 research outputs found

    Civil Uses of Remotely Piloted Aircraft

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    The technology effort is identified and assessed that is required to bring the civil uses of RPVs to fruition and to determine whether or not the potential market is real and economically practical, the technologies are within reach, the operational problems are manageable, and the benefits are worth the cost. To do so, the economic, technical, and environmental implications are examined. The time frame is 1980-85. Representative uses are selected; detailed functional and performance requirements are derived for RPV systems; and conceptual system designs are devised. Total system cost comparisons are made with non-RPV alternatives. The potential market demand for RPV systems is estimated. Environmental and safety requirements are examined, and legal and regulatory concerns are identified. A potential demand for 2,000-11,000 RPV systems is estimated. Typical cost savings of 25-35% compared to non-RPV alternatives are determined. There appear to be no environmental problems, and the safety issue appears manageable

    John Chalmers DaCosta (1863-1933): restoration of the old operating table.

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    John Chalmers DaCosta was an influential chairman and the first Samuel D. Gross Professor of Surgery at Jefferson Medical College in Philadelphia. He was well known throughout the field as a skilled surgeon, passionate speaker, and exceptional writer. In addition to countless accomplishments during his career, DaCosta was deeply dedicated to the preservation and commemoration of surgical history. This ideology was exemplified when he set out on a mission to recover the old wooden operating table used by many of his iconic mentors including Samuel D. Gross, Joseph Pancoast, and William W. Keen. This table was originally used for surgical demonstrations and anatomy lessons in a lecture room of the Ely Building and later in the great amphitheater of the Jefferson Sansom Street Hospital. It was found forgotten in the basement of the College Building and was promptly refurbished, donned with dedicatory plaques, and returned to its honored position in the medical college. Dr. DaCosta also contributed a detailed article recalling the history of the table and the notable leaders in surgery who taught and practiced on its surface. The old table currently stands proudly in the entranceway of the Department of Surgery where it will remain as a cherished symbol of the early beginnings of surgical practice and education

    Electrochemical AFM : understanding the electromaterial-cellular interface

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    Organic conducting polymers are emerging as an exciting new class of biomaterial that can be used to enhance and control the growth of mammalian cells for tissue regeneration and engineering application

    Thoracic Epidural analgesia versus Rectus Sheath Catheters for open midline incisions in major abdominal surgery within an enhanced recovery programme (TERSC):study protocol for a randomised controlled trial

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    BACKGROUND: Thoracic epidural analgesia (TEA) is recommended for post-operative pain relief in patients undergoing major abdominal surgery via a midline incision. However, the effectiveness of TEA is variable with high failure rates reported post-operatively. Common side effects such as low blood pressure and motor block can reduce mobility and hinder recovery, and a number of rare but serious complications can also occur following their use.Rectus sheath catheters (RSC) may provide a novel alternative approach to somatic analgesia without the associated adverse effects of TEA. The aim of this study is to compare the efficacy of both techniques in terms of pain relief, patient experience, post-operative functional recovery, safety and cost-effectiveness. METHODS/DESIGN: This is a single-centre randomised controlled non-blinded trial, which also includes a nested qualitative study. Over a two-year period, 132 patients undergoing major abdominal surgery via a midline incision will be randomised to receive either TEA or RSC for post-operative analgesia. The primary outcome measures pain scores on moving from a supine to a sitting position at 24 hours post wound closure, and the patient experience between groups evaluated through in-depth interviews. Secondary outcomes include pain scores at rest and on movement at other time points, opiate consumption, functional recovery, morbidity and cost-effectiveness. DISCUSSION: This will be the first randomised controlled trial comparing thoracic epidurals to ultrasound-guided rectus sheath catheters in adults undergoing elective midline laparotomy. The standardised care provided by an Enhanced Recovery Programme makes this a comparison between two complex pain packages and not simply two analgesic techniques, in order to ascertain if RSC is a viable alternative to TEA. TRIAL REGISTRATION: Current Controlled Trials ISRCTN81223298 (16 January 2014)

    Processable aqueous dispersions of graphene nanosheets

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    Graphene sheets offer extraordinary electronic, thermal and mechanical properties and are expected to ๏ฌnd a variety of applications. A prerequisite for exploiting most proposed applications for graphene is the availability of processable graphene sheets in large quantities. The direct dispersion of hydrophobic graphite or graphene sheets in water without the assistance of dispersing agents has generally been considered to be an insurmountable challenge. Here we report that chemically converted graphene sheets obtained from graphite can readily form stable aqueous colloids through electrostatic stabilization. This discovery has enabled us to develop a facile approach to large-scale production of aqueous graphene dispersions without the need for polymeric or surfactant stabilizers. Our ๏ฌndings make it possible to process graphene materials using low-cost solution processing techniques, opening up enormous opportunities to use this unique carbon nanostructure for many technological applications

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    Stage-Specific Sampling by Pattern Recognition Receptors during Candida albicans Phagocytosis

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    Candida albicans is a medically important pathogen, and recognition by innate immune cells is critical for its clearance. Although a number of pattern recognition receptors have been shown to be involved in recognition and phagocytosis of this fungus, the relative role of these receptors has not been formally examined. In this paper, we have investigated the contribution of the mannose receptor, Dectin-1, and complement receptor 3; and we have demonstrated that Dectin-1 is the main non-opsonic receptor involved in fungal uptake. However, both Dectin-1 and complement receptor 3 were found to accumulate at the site of uptake, while mannose receptor accumulated on C. albicans phagosomes at later stages. These results suggest a potential role for MR in phagosome sampling; and, accordingly, MR deficiency led to a reduction in TNF-ฮฑ and MCP-1 production in response to C. albicans uptake. Our data suggest that pattern recognition receptors sample the fungal phagosome in a sequential fashion

    A systematic review of rehabilitation in chronic heart failure:evaluating the reporting of exercise interventions

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    Abstract A large body of research supports the use of exercise to improve symptoms, quality of life, and physical function in patients with chronic heart failure. Previous reviews have focused on reporting outcomes of exercise interventions such as cardiorespiratory fitness. However, none have critically examined exercise prescription. The aim of this review was to evaluate the reporting and application of exercise principles in randomised control trials of exercise training in patients with chronic heart failure. A systematic review of exercise intervention RCTs in patients with CHF, using the Consensus on Exercise Reporting Template (CERT), was undertaken. The Ovid Medline/PubMed, Embase, Scopus/Web of Science, and Cochrane Library and Health Technology Assessment Databases were searched from 2000 to June 2020. Prospective RCTs in which patients with CHF were randomized to a structured exercise programme were included. No limits were placed on the type or duration of exercise structured exercise programme or type of CHF (i.e. preserved or reduced ejection fraction). We included 143 studies, comprising of 181 different exercise interventions. The mean CERT score was 10 out of 19, with no study achieving a score of 19. Primarily, details were missing regarding motivational strategies, homeโ€based exercise components, and adherence/fidelity to the intervention. Exercise intensity was the most common principle of exercise prescription missing from intervention reporting. There was no improvement in the reporting of exercise interventions with time (R2ย =ย 0.003). Most RCTs of exercise training in CHF are reported with insufficient detail to allow for replication, limiting the translation of evidence to clinical practice. We encourage authors to provide adequate details when reporting future interventions. Where journal word counts are restrictive, we recommend using supplementary material or publishing trial protocols prior to beginning the study
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