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Taking the Chinese city of Xiamen as an example, simulation and quantitative analysis were performed on the transmissions of the Coronavirus Disease 2019(COVID-19) and the influence of intervention combinations to assist policymakers in the preparation of targeted response measures. A machine learning model was built to estimate the effectiveness of interventions and simulate transmission in different scenarios. The comparison was conducted between simulated and real cases in Xiamen. A web inter...  相似文献   
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An essential role of critical care advanced practice providers—advanced practice registered nurses and physician assistants—is to have knowledge and competency to make accurate and efficient decisions. The ability to manage clinical scenarios involving medically deteriorating patients requires higher-order cognitive thinking and leadership skills that are challenging to extrapolate in traditional interviews. In critical care, advanced practice providers must make rapid clinical assessments and implement appropriate medical interventions to deter progression of life-threatening illnesses. Adding clinical simulation to the traditional interview allows interviewers to evaluate applicants’ crisis resource management skills, leadership, and clinical competency.  相似文献   
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Oral and maxillofacial surgery (OMS) teaching is set to undergo a paradigm shift towards competency-based training. With increasing focus on resident skill development and patient safety, computerized simulators are likely to play a more mainstream role in OMS training. A systematic review of the available literature was conducted, in accordance with the PRISMA guidelines, to highlight the scope of computerized simulation in OMS teaching. A PubMed search was performed by two independent reviewers, and 35 articles published in English between 2010 and 2021 that reported the use of computerized simulation for teaching maxillofacial procedures were included in the analysis. Eight articles on minor oral surgery, seven on orthognathic surgery, five on maxillofacial trauma, five on cleft lip and palate surgery, three articles each on nerve block techniques, endoscopic procedures, and reconstructive surgery, and one article on fibre-optic intubation reported the use of computerized simulation that can be applied to OMS training. Ten randomized controlled trials were identified in the search. However there was marked heterogeneity among the studies. Simulator training for skill acquisition mentored by an expert OMS educator could offer holistic resident training; however more studies that test common themes of resident training such as knowledge acquisition and skill development are necessary.  相似文献   
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目的:探讨建立一种放射治疗全身器官剂量数据库平台的可行性。方法:使用基于深度学习的自动勾画软件DeepViewer?1例食管癌患者的全身CT上勾画全身器官,然后利用基于GPU加速的蒙特卡罗软件ARCHER计算相应的器官剂量分布,最后利用Lyman-Kutcher-Burman(LKB)模型评估放疗患者正常组织并发症概率(NTCP)。结果:针对该病例,成功建立基于DeepViewer?ARCHER和LKB模型的全身器官剂量数据库,发现距离靶区越近的器官剂量越大,其中心脏与靶区间距离最小,剂量为14.11 Gy,但因其模型参数特殊,通过LKB模型计算的NTCP为0.00%;左、右肺的剂量分别为3.19和1.16 Gy,但是NTCP值却很大,分别为2.13%和1.60%。对于距离靶区较远的头颈部器官(视交叉、视神经和眼)和腹部器官(直肠、膀胱和股骨头)剂量分别约为9和2 mGy,并且NTCP均近似为0.00%。结论:研究结果证明通过自动勾画软件DeepViewer?蒙特卡罗软件ARCHER和LKB模型建立全身器官剂量数据库的可行性。  相似文献   
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Purpose

Using volumetric modulated arc therapy (VMAT) delivery technique gantry position, multi-leaf collimator (MLC) as well as dose rate change dynamically during the application. However, additional components can be dynamically altered throughout the dose delivery such as the collimator or the couch. Thus, the degrees of freedom increase allowing almost arbitrary dynamic trajectories for the beam. While the dose delivery of such dynamic trajectories for linear accelerators is technically possible, there is currently no dose calculation and validation tool available. Thus, the aim of this work is to develop a dose calculation and verification tool for dynamic trajectories using Monte Carlo (MC) methods.

Methods

The dose calculation for dynamic trajectories is implemented in the previously developed Swiss Monte Carlo Plan (SMCP). SMCP interfaces the treatment planning system Eclipse with a MC dose calculation algorithm and is already able to handle dynamic MLC and gantry rotations. Hence, the additional dynamic components, namely the collimator and the couch, are described similarly to the dynamic MLC by defining data pairs of positions of the dynamic component and the corresponding MU-fractions. For validation purposes, measurements are performed with the Delta4 phantom and film measurements using the developer mode on a TrueBeam linear accelerator. These measured dose distributions are then compared with the corresponding calculations using SMCP. First, simple academic cases applying one-dimensional movements are investigated and second, more complex dynamic trajectories with several simultaneously moving components are compared considering academic cases as well as a clinically motivated prostate case.

Results

The dose calculation for dynamic trajectories is successfully implemented into SMCP. The comparisons between the measured and calculated dose distributions for the simple as well as for the more complex situations show an agreement which is generally within 3% of the maximum dose or 3 mm. The required computation time for the dose calculation remains the same when the additional dynamic moving components are included.

Conclusion

The results obtained for the dose comparisons for simple and complex situations suggest that the extended SMCP is an accurate dose calculation and efficient verification tool for dynamic trajectory radiotherapy. This work was supported by Varian Medical Systems.  相似文献   
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Emergency front-of-neck access to achieve a percutaneous airway can be a life-saving intervention, but there is debate about the preferred technique. This prospective, observational study was designed to compare the two most common emergency surgical airway techniques in a wet lab simulation using an ovine model. Forty-three doctors participated. After providing standardised reading, a lecture and dry lab benchtop training, participants progressed to a high-fidelity wet lab simulation. Participants entered an operating theatre where a ‘cannot intubate, cannot oxygenate’ situation had been declared and were directed to perform emergency front-of-neck access: first with a cannula technique (14-gauge cannula insertion with ventilation using a Rapid-O2® cricothyroidotomy insufflation device); and subsequently, a scalpel-bougie technique (surgical incision, bougie insertion into trachea and then tracheal tube passed over bougie, with ventilation using a self-inflating bag). The primary end-point was time from declaration of ‘cannot intubate, cannot oxygenate’ to delivery of oxygen via a correctly placed percutaneous device. If a cannula or tracheal tube was not placed within 240 s, the attempt was marked as a failure. There was one failure for the cannula approach and 15 for the scalpel-bougie technique (OR 0.07 (95%CI 0.00–0.43); p <0.001). Median (IQR [range]) time to oxygenation, if successful, was 65 (57–78 [28–160]) s for the cannula approach and 90 (74–115 [40–265]) s for the scalpel-bougie technique (p=0.005). In this ovine model, emergency front-of-neck access using a cannula had a lower chance of failure and (when successful) shorter time to first oxygen delivery compared with a scalpel-bougie technique.  相似文献   
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