Magnetron Sputtered CsPbCl3 Perovskite Detectors as Real-Time Dosimeters for Clinical Radiotherapy

The aim of this study is to investigate the feasibility of manufacturing thin real-time relative dosimeters for clinical radiotherapy (RT) with potential applications for transmission monitoring in vivo dosimetry and pre-treatment dose verifications. Thin (≈1 μm) layers of a high sensitivity, wide bandgap semiconductor, the inorganic perovskite CsPbCl₃, have been grown for the first time by magnetron sputtering on plastic substrates equipped with electrode arrays. Prototype devices have been tested in real-time configuration to evaluate the dose delivered by a 6 MV photon beam from a linear accelerator. Linearity of the charge with the dose has been verified over three order of magnitudes, linearity of the current signal with the dose rate has been also successfully tested in the range 0.5-4.3 Gy/min. The combination of high sensitivity per unit volume and wide bandgap provides high signal-to-noise ratios, up to 70, even at moderate applied voltages. The Schottky diode configuration allows the detector to operate without bias voltage (null bias).The blocking-barrier structure allows to confine the active volume within sub-millimetric sizes, a quite attractive feature in view to increase granularity and achieve the high spatial resolutions required in modern RT techniques. All the above-mentioned features indeed pave the way to a novel generation of flexible, transmission, real time dosimeters for clinical radiotherapy.     

Placing volunteered geographic health information: Socio-spatial bias in 311 bed bug report data for New York City

Health researchers and policy-makers increasingly use volunteered geographic information (VGI) to analyze spatial variation in health and wellbeing and to develop interventions. As socially constructed data, health VGI reflect the people who perceive issues and choose to report them, and the digital systems that structure the reporting process. We propose a conceptual framework that describes the interlocking effects of socioeconomic, behavioral, geographic, and technological processes on VGI accuracy and credibility. GIS and statistical methods are used to analyze social and geographical biases in health-related VGI through a case study of bed bug complaint data from New York City's 311 system. Reports of bed bug infestation from 311 are mapped and modeled to uncover associations with socioeconomic and built environment characteristics. Factors associated with bed bug report credibility are examined by comparing characteristics of confirmed reports with those for reports in which inspectors found no evidence of infestation (negative reports). A multilevel model of credibility incorporating report-, building-, and tract-level variables reveals strong geographical and socioeconomic biases, with negative reports generated more frequently from high-value residential buildings located in high-income neighborhoods with predominately white, non-Hispanic populations. Using 311 data for all bed bug reports, rather than confirmed reports, obscures the burden of these pests in high poverty neighborhoods and diminishes socioeconomic disparities. Mistaken reporting also has economic costs, as each report triggers an inspection by city inspectors that entails time, monetary, and opportunity costs.     

基于离散型地理信息的H7N9流感病毒动态时空传播模式

目的 基于离散型的地理信息构建了H7N9病毒时空动态传播模式图，探索H7N9病毒的空间传播路径。方法 选取全球共享禽流感数据倡议组织（GISAID）中中国以人类为宿主的H7N9流感病毒血凝素（HA）和神经酰胺酶（NA）基因序列，利用BioEdit 7.0软件进行多序列比对。在贝叶斯理论框架下，运用BEAST 1.8.2软件构建H7N9时空传播模型，采用symmetric substitution model和贝叶斯随机搜索变量选择（BBSVS）方法，对H7N9的历史传播轨迹进行推断和检验。以Google Earth软件展现H7N9病毒的时空传播动态图。结果 感染人类的H7N9病毒起源于上海或杭州，最早可追溯到2012年10月。并在2013年3、4月份开始传向邻近省份，同年8、9月份传播加剧，3个月内传向10余处地区。结论 基于基因核苷酸序列和空间地理信息，追踪了H7N9病毒历史传播轨迹，为早期流感疫情的防控及病毒的溯源提供线索。     

Spatial distribution of intestinal parasitic infections in a Kaingáng indigenous village from Southern Brazil

The spatial distribution of enteroparasitosis in an indigenous village from Paraná was evaluated to identify areas of risk for these infections. A cross-sectional study (from November 2010 to June 2011) was performed using Three Faecal Test^® and Kato &; Katz method and a questionnaire on housing and hygiene conditions was administered. Local geostatistical analyses were performed to determine the spatial distribution of intestinal parasitic infections. The overall prevalence of enteroparasites was 67.2?% (457/680), and the most prevalent taxa were Ascaris lumbricoides (48.8?%) and Trichuris trichiura (44.7?%). The prevalence of heavy infection by soil-transmitted helminths was 3.6?% and the families lived in houses with an average of 5.1 residents and < 2 bedrooms per household. The average number of species per individual present spatial heterogeneity with the highest values (≥0.8) in areas with high clustering of residences. The visualization of the spatial distribution of intestinal parasites in this indigenous village is an important contribution to determining health risk areas and planning decisions and services.     

不同地理居群新塔花的ITS2和psbA-trnH序列及聚类分析

目的:分析18个不同地理居群新塔花的内转录间隔区(ITS)2和psbA-trnH序列,为其种质资源评价和基原药用植物遗传多样性分析提供参考。方法:试剂盒法提取新塔花基因组DNA,聚合酶链式反应(PCR)扩增ITS2和psbA-trnH间隔区序列,双向测序,拼接,基于Kimura两参数模型(K2P)构建邻接法(NJ)系统发育树。结果:不同地理居群新塔花ITS2和psbA-trnH序列均有种内差异。ITS2序列长度平均为236 bp,检测有9个单倍型,遗传距离为0～0. 022,不同地理居群新塔花聚为两支,XTH3,XTH6,XTH9等10个地理居群聚为一支,XTH4,XTH5,XTH10等8个地理居群聚为另一支。除XTH6的psbAtrnH序列存在6 bp缺失外,其他地理居群的psbA-trnH序列长度均为355 bp,检测有4个单倍型,遗传距离为0～0. 023,不同地理居群新塔花聚为两支,XTH1,XTH3,XTH4等12个地理居群聚为一支,XTH14,XTH17,XTH18聚为另一支。基于ITS2+psbA-trnH组合序列的系统发育(NJ)树显示,不同地理居群的新塔花可分为两支,XTH11,XTH12,XTH16等12个地理居群聚为一支,XTH14,XTH17,XTH18聚为另一支。结论:不同地理居群的新塔花地理位置接近或相似,相对遗传距离较小,亲缘关系较为接近,说明不同地理居群新塔花的亲缘关系及其遗传多样性与地理位置相关。