187,233 research outputs found

    Anatomy of Green Open Access

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    Open Access (OA) is the free unrestricted access to electronic versions of scholarly publications. For peer reviewed journal articles there are two main routes to OA, publishing in OA journals (gold OA) or archiving of article copies or manuscripts at other web locations (green OA). This study focuses on summarizing and extending upon current knowledge about green OA. A synthesis of previous studies indicates that the green OA coverage of all published journal articles is approximately 12 %, with substantial disciplinary variation. Typically, green OA copies become available with considerable time delays, partly caused by publisher imposed embargo periods, and partly by author tendencies to archive manuscripts only periodically. Although green OA copies should ideally be archived in proper repositories, a large share is stored on home pages and similar locations, with no assurance of long-term preservation. Often such locations contain exact copies of published articles, which may infringe on the publisher’s exclusive rights. The technical foundation for green OA uploading is becoming increasingly solid, which is largely due to the rapid increase in the number of institutional repositories. The number of articles within the scope of OA mandates, which strongly influence the self- archival rate of articles, is nevertheless still low.peerReviewe

    Circular frame fixation for calcaneal fractures risks injury to the medial neurovascular structures: a cadaveric description

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    Aim: There is a risk of iatrogenic injury to the soft tissues of the calcaneus and this study assesses the risk of injury to these structures in circular frame calcaneal fracture fixation. Materials and Methods: After olive tip wires were inserted, an L-shaped incision on the lateral and medial aspects of 5 formalin fixed cadaveric feet was performed to expose the underlying soft tissues. The calcaneus was divided into zones corresponding to high, medium and low risk using a grading system. Results: Structures at high risk included the posterior tibial artery, posterior tibial vein and posterior tibial nerve on the medial aspect. Soft tissue structures on the lateral side that were shown to be at lower risk of injury were the small saphenous vein and the sural nerve and the tendons of fibularis longus and fibularis brevis. Conclusion: The lateral surface of the calcaneus provides a lower risk area for external fixation. The risk of injury to significant soft tissues using a circular frame fixation approach has been shown to be greater on the medial aspect. Clinical Relevance: This study highlights the relevant anatomical relations in circular frame fixation for calcaneal fractures to minimize damage to these structures

    3D printing is a transformative technology in congenital heart disease

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    Survival in congenital heart disease has steadily improved since 1938, when Dr. Robert Gross successfully ligated for the first time a patent ductus arteriosus in a 7-year-old child. To continue the gains made over the past 80 years, transformative changes with broad impact are needed in management of congenital heart disease. Three-dimensional printing is an emerging technology that is fundamentally affecting patient care, research, trainee education, and interactions among medical teams, patients, and caregivers. This paper first reviews key clinical cases where the technology has affected patient care. It then discusses 3-dimensional printing in trainee education. Thereafter, the role of this technology in communication with multidisciplinary teams, patients, and caregivers is described. Finally, the paper reviews translational technologies on the horizon that promise to take this nascent field even further

    Aqueous Humor Outflow Structure and Function Imaging At the Bench and Bedside: A Review.

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    Anterior segment glaucoma clinical care and research has recently gained new focus because of novel imaging modalities and the advent of angle-based surgical treatments. Traditional investigation drawn to the trabecular meshwork now emphasizes the entire conventional aqueous humor outflow (AHO) pathway from the anterior chamber to the episcleral vein. AHO investigation can be divided into structural and functional assessments using different methods. The historical basis for studying the anterior segment of the eye and AHO in glaucoma is discussed. Structural studies of AHO are reviewed and include traditional pathological approaches to modern tools such as multi-model two-photon microscopy and optical coherence tomography. Functional assessment focuses on visualizing AHO itself through a variety of non-real-time and real-time techniques such as aqueous angiography. Implications of distal outflow resistance and segmental AHO are discussed with an emphasis on melding bench-side research to viable clinical applications. Through the development of an improved structure: function relationship for AHO in the anterior segment of the normal and diseased eye, a better understanding of the eye with improved therapeutics may be developed

    Optimization of treatment planning workflow and tumor coverage during daily adaptive magnetic resonance image guided radiation therapy (MR-IGRT) of pancreatic cancer

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    Abstract Background To simplify the adaptive treatment planning workflow while achieving the optimal tumor-dose coverage in pancreatic cancer patients undergoing daily adaptive magnetic resonance image guided radiation therapy (MR-IGRT). Methods In daily adaptive MR-IGRT, the plan objective function constructed during simulation is used for plan re-optimization throughout the course of treatment. In this study, we have constructed the initial objective functions using two methods for 16 pancreatic cancer patients treated with the ViewRay™ MR-IGRT system: 1) the conventional method that handles the stomach, duodenum, small bowel, and large bowel as separate organs at risk (OARs) and 2) the OAR grouping method. Using OAR grouping, a combined OAR structure that encompasses the portions of these four primary OARs within 3 cm of the planning target volume (PTV) is created. OAR grouping simulation plans were optimized such that the target coverage was comparable to the clinical simulation plan constructed in the conventional manner. In both cases, the initial objective function was then applied to each successive treatment fraction and the plan was re-optimized based on the patient’s daily anatomy. OAR grouping plans were compared to conventional plans at each fraction in terms of coverage of the PTV and the optimized PTV (PTV OPT), which is the result of the subtraction of overlapping OAR volumes with an additional margin from the PTV. Results Plan performance was enhanced across a majority of fractions using OAR grouping. The percentage of the volume of the PTV covered by 95% of the prescribed dose (D95) was improved by an average of 3.87 ± 4.29% while D95 coverage of the PTV OPT increased by 3.98 ± 4.97%. Finally, D100 coverage of the PTV demonstrated an average increase of 6.47 ± 7.16% and a maximum improvement of 20.19%. Conclusions In this study, our proposed OAR grouping plans generally outperformed conventional plans, especially when the conventional simulation plan favored or disregarded an OAR through the assignment of distinct weighting parameters relative to the other critical structures. OAR grouping simplifies the MR-IGRT adaptive treatment planning workflow at simulation while demonstrating improved coverage compared to delivered pancreatic cancer treatment plans in daily adaptive radiation therapy

    Redbook: 1997

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    Advice compiled by Boston University School of Medicine students for incoming first year students and third or fourth year students preparing for clinical rotations
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