Six lessons from introducing sweetened beverage taxes in Berkeley,Cook County,and Philadelphia: A case study comparison in agenda setting and decision making

Sweetened beverage (SB) taxes have recently been introduced to prevent obesity by several governments, but limited information on related policy adoption processes hampers further diffusion. We investigated the agenda-setting and decision-making phases of SB tax reforms in Berkeley and Philadelphia (where it was successfully adopted), and Cook County (where it was repealed). A web-based survey, semi structured stakeholder interviews, and a local media coverage analysis were used to collect information. Findings were structured and analyzed using the health policy triangle of Buse, Mays and Walt. Six general lessons emerged. First, the policy was coupled to existing high-agenda items (e.g., financing pre-kindergarten in Philadelphia). Second, policy framing had to align prevailing political sentiments, as expressed in media (e.g., ‘Berkeley vs. Big Soda’ echoed skepticism of corporate influence in politics). Third, existing tax policies and political decision-making rules were important (e.g., confusion how the SB tax related to state and federal taxes fueled Cook County opposition). Fourth, the tax structure required technical and political considerations during policy formulation (e.g., artificially-sweetened beverages were included in Philadelphia to counteract arguments that the tax was regressive). Fifth, it was important to build an advocacy coalition upfront (e.g., the Berkeley coalition was constructed prior to announcing the attempt). Sixth, successful advocacy coalitions were locally grounded and influenced local media (e.g., the Cook County opposition engaged local retailers).     

经颅磁刺激的多尺度建模仿真研究

经颅磁刺激是一种无创无痛的电磁刺激手段，被广泛应用于神经调控，在临床上对多种精神疾病和神经类疾病有明显的治疗效果。本文从电磁场建模仿真，细胞跨膜电位建模仿真，以及神经元响应建模仿真3个方面对经颅磁刺激多尺度建模仿真研究进行了详细的综述，并提出现阶段存在的问题以及对未来的展望。经颅磁刺激的多尺度建模仿真对磁刺激仪的设计开发具有指导意义，对磁刺激的导航系统提供重要的理论基础，有助于我们更好的理解电磁刺激的神经调控机制。     

浙江省德清县县域医共体改革措施与效果分析

目的：分析浙江省德清县县域医共体改革措施及阶段性成效。方法：定性访谈了解医共体整合措施，定量分析医共体建设前后（2016-2018年）各级医疗机构医疗服务利用数据及医共体部分绩效考核数据。结果：医共体在组织、管理、功能、服务方面进行整合，并取得阶段成效：医保基金在县域内支出率有所增加；乡镇卫生院卫生人员数量、医疗收入有所提高，乡镇卫生院住院病人人均医药费有所降低。结论：医共体取得初期成效，应开展以患者健康结局指标为主的长期追踪调查，全面系统评估医共体；保留基层医疗机构地位、功能定位不变；探索实行医共体"总额预付、结余奖励"制度，将医共体发展成以患者健康为中心、基于利益共享机制、分工合作的责任利益共同体。     

Radiography Students' Learning of Plain X-Ray Examinations in Simulation Laboratory Exercises: An Ethnographic Research

IntroductionIn addition to lessons and clinical training, simulation-based learning has become more ubiquitous in radiography students' learning. Plain examinations are in the core of radiography, and studying how students learn them in simulation is therefore essential when considering students' professional development. The purpose of this study was to describe radiography students' learning to perform plain X-ray examinations in simulation laboratory exercises. The aim was to understand how the students learned.MethodsThe data were gathered by observing and interviewing 17 radiography students as they performed laboratory exercises of plain X-ray examinations before clinical training. Learning was understood according to social constructivism and was examined from the perspective of interpretive ethnography. Data were analyzed using the constant comparative method.ResultsIn simulation laboratory exercises, radiography students learned by model-based experimentation. Learning consisted of imaging bone and chest examinations of a manikin, evaluation of the images, and patient positioning and guidance among students. The learning method was collaborative learning. Three learning outcomes were found: simulation promoted theory-practice connection, simulation guided the students to follow instructions, and simulation strengthened collaboration between students. The factors supporting and impeding learning were the same: academic studies before the simulation and learning tasks. In addition, experimentation without teacher's supervision was an impeding factor for some students.ConclusionSimulation laboratory exercises with a manikin proved to be a useful learning method for radiography students in learning to perform plain X-ray examinations. The results indicated the need to pay attention to simulation pedagogy and students' academic skills.     

A model-based analysis of pharmacokinetic–pharmacodynamic (PK/PD) indices of avibactam against Pseudomonas aeruginosa

ObjectiveThe aim of the present work was to use a semi-mechanistic pharmacokinetic–pharmacodynamic (PK/PD) model developed from in vitro time–kill measurements with P. aeruginosa to compare different pharmacodynamic indices derived from simulated human avibactam exposures, with respect to their degree of correlation with the modelled bacterial responses.MethodsA mathematical model of the effect of ceftazidime–avibactam on the growth dynamics of P. aeruginosa was used to simulate bacterial responses to modelled human exposures from fractionated avibactam dosing regimens with a fixed ceftazidime dosing regimen (2 or 8 g q8h as a 2-h infusion). The relatedness of the 24-h change in bacterial density and avibactam exposure parameters was evaluated to determine exposure parameter that closely correlated with bacterial growth/killing responses.ResultsFrequent dosing was associated with higher efficacy, resulting in a reduction of avibactam daily dose. The best-fit PD index of avibactam determined from the simulation was fT > C_T of 1 mg/L avibactam and q8h was the longest dosing interval able to achieve 2-log kill: 41–87% (3.3 h to 7.0 h out of 8-h interval, respectively). The avibactam exposure magnitude required to achieve a 2-log kill in the simulations was dependent on the susceptibility of the bacterial isolate to ceftazidime.ConclusionsAvibactam activity in combination with ceftazidime against multidrug resistant P. aeruginosa correlated with fT > C_T. Setting a threshold avibactam concentration to 1 mg/L, superimposed over a simulated human-like exposure of ceftazidime, achieved at least 2-log kill for the clinical dose of 500 mg q8h avibactam as a 2-h infusion, depending on the minimum inhibitory concentration of ceftazidime alone.     

Predicting the outcome of transcatheter mitral valve implantation using image-based computational models

BackgroundThe appropriate placement and size selection of mitral prostheses in transcatheter mitral valve implantation (TMVI) is critical, as encroachment on the left ventricular outflow tract (LVOT) may lead to flow obstruction. Recent advances in computed tomography (CT) can be employed for pre-procedural planning of mitral prosthetic valve placement. This study aims to develop patient-specific computational fluid dynamics models of the left ventricle (LV) in the presence of a mitral valve prosthesis to investigate blood flow and LVOT pressure gradient during systole.MethodsPatient-specific computational fluid dynamics simulations of TMVI with varied cardiac anatomy and insertion angles were performed (n = 30). Wide-volume full cycle cardiovascular CT images prior to TMVI were used as source anatomical data (n = 6 patients). Blood movement was governed by Navier-Stokes equations and the LV endocardial wall deformation was derived from each patient's CT images.ResultsThe computed pressure gradients in the presence of the mitral prosthesis compared well with clinically measured gradients. Analysis of the effects of prosthetic valve angulation, aorto-mitral annular angle, ejection fraction, LV size and new LVOT area (neo-LVOT) after TMVI in silico revealed that the neo-LVOT area (p < 0.001) was the most significant factor affecting LVOT pressure gradient. Angulation of the mitral valve can substantially mitigate LVOT gradient.ConclusionsComputational fluid dynamics simulation is a promising method to aid in pre-TMVI planning and understanding the factors underlying LVOT obstruction.     

Monte Carlo based analysis and evaluation of energy spectrum for low-kV IORT spherical applicators

Low-kV IORT is an increasing modality for breast cancer treatment. Soft X-rays from INTRABEAM (Carl Zeiss Meditec AG, Oberkochen, Germany), a dedicated IORT device along with special spherical applicators are employed for this purpose. A Monte Carlo model of INTRAMBEAM and spherical applicators are introduced in the current study to evaluate the dosimetric and physical characteristics of emitted X-rays from the bare probe and different applicator diameters.X-ray probe and different applicator diameters of 1.5 cm to 5 cm were simulated by GEANT4 Monte Carlo Toolkit. Then, the validity of the simulated model was evaluated by comparing the Monte Carlo based PDD (percentage depth dose) and anisotropy data with those reported by the manufacturer. Finally, the physical characteristics of X-rays such as the mean and most probable energy as well as the LET of secondary electrons were obtained and analyzed.There was a good agreement between the simulated and reported PDDs for bare probe and different applicator diameters. The anisotropy values were also within an exemplary range reported by the manufacturer. The X-ray mean energy shifts from 25.6keV to 28.6keV with variations of applicator diameter. The maximum variation of the secondary electron LET was 9% with changing the applicator diameter.The usefulness of GEANT4 Toolkit for Monte Carlo based commissioning of INTRABEAM machine was confirmed in the current study. The variations of the applicator diameter slightly changed the physical characteristics of low-kV X-rays and LET of secondary electrons which cannot considerably affect the relative biologic effectiveness (RBE) for different applicator diameters.     

The link between language and action in aging

ObjectiveMany studies have demonstrated the existence of a link between action verb processing and action. However, little is known about the changes in this relationship with aging.MethodTo assess this point, we compare the performances of younger and older people during a priming task consisting of judging whether an image contains a human after listening to an action verb.ResultsIn accordance with previous literature, the results showed that younger people were faster to detect the presence of a human in the image in congruent conditions, namely, when the action verb and the image refer to the same action. However, this effect was not present in older adults’ participants.ConclusionThese findings suggest that the link between action and language decreases with age. We discuss these findings in the context of the embodied view of cognition.