Metal-Halide Perovskite Submicrometer-Thick Films for Ultra-Stable Self-Powered Direct X-Ray Detectors

Metal-halide perovskites are revolutionizing the world of X-ray detectors,due to the development of sensitive,fast,and cost-effective devices.Self-powered operation,ensuring portability and low power consumption,has also been recently demonstrated in both bulk materials and thin films.However,the signal stability and repeatability under continuous X-ray exposure has only been tested up to a few hours,often reporting degradation of the detection performance.Here it is shown that self-powered direct X-ray detectors,fabricated starting from a FAPbBr_(3)submicrometer-thick film deposition onto a mesoporous TiO_(2)scaffold,can withstand a 26-day uninterrupted X-ray exposure with negligible signal loss,demonstrating ultra-high operational stability and excellent repeatability.No structural modification is observed after irradiation with a total ionizing dose of almost 200 Gy,revealing an unexpectedly high radiation hardness for a metal-halide perovskite thin film.In addition,trap-assisted photoconductive gain enabled the device to achieve a record bulk sensitivity of 7.28 C Gy^(−1)cm^(−3)at 0 V,an unprecedented value in the field of thin-film-based photoconductors and photodiodes for“hard”X-rays.Finally,prototypal validation under the X-ray beam produced by a medical linear accelerator for cancer treatment is also introduced.

Preparation of Air Film for Medical Infusion Device and Study on Air Permeability and Water Resistance

Polypropylene melt-blown nonwoven was used as the substrate for the preparation of an air film. The nonwoven was immersed in the casting solution at first,and then respectively placed in the first coagulation bath,the second coagulation bath and the finishing liquid containing fluorine additive aqueous solution of 20 g/L. At last,the high temperature drying was carried out to obtain the air permeable and water resistant air film. With analyses and comparisons of the isopropanol alcohol content,the residence time of air,the composition of the first coagulation bath and the residence time of the first coagulation,the optimum parameters were found and the air film had an air permeability of 4. 7 L/min,a water blocking pressure of 16 kPa,a contact angle of 134. 2°,and a mean pore size of 2. 089 1 μm.

Image Processing of Biological Liquids Films for Medical Diagnostics

In this paper, the development of smart medical autonomous technology is considered. An example of a smart medical autonomous distributed system for diagnostics is also discussed. To develop this system for medical image analysis we review several processing methods. The use of the cuneiform dehydration method for medical diagnosis is considered. The experimental results obtained for blood serum dehydrated films are presented. The author proposes an algorithm for the primary identification of structures formed in the films and their use for automated detection of various structures for diagnostic purposes. The paper describes the first stage of image processing, i.e. the selection of filtering types for the correct identification of structural features and characteristics of the images. The results of filtering and some computational results of various types of structures in the films are presented.

Preparation and photo-catalytic activity of TiO_2-coated medical stone-based porous ceramics

Medical stone-based porous ceramics as a carrier were prepared by ultra-fine grinding and low-temperature sintering method. Nano-TiO~ thin films were loaded on the carrier by chemical liquid deposition method using titanium tetrachloride as a precursor. The micro-morphology and microstructure of the synthesized samples were characterized using X-ray diffraction, scanning electron microscopy with energy dispersive spectrometry, and mercury injection method. The photo-catalytic activity of the TiO2 thin films was investigated by degrading formaldehyde. The main crystalline phase in the TiO2 thin films calcined at 550~C is anatase with the average particle size about 10 nm. The specific surface area of the carrier-coated nano-TiO2 increases from 3.68 to 5.32 m2/g. The formaldehyde removal rate of the TiO2/medical stone-based porous ceramics irradiated under an ultraviolet lamp for 120 min reaches 85.6%.

Direct Measurement of Medical Linear Accelerator Electron Beam Width at Scattering Foil Position

Purpose: The aim of this study was to develop a method for the direct measurement of electron beam width and distribution at the scattering foil on the carrousel in a medical linear accelerator gantry head, which differs from an existing indirect method for measuring the focal spot size using a camera or metallic slit located outside the gantry head. Methods: The electron beam emitted by the linear accelerator was used to irradiate radiochromic film mounted on the scattering foil on the carrousel, which was not used for clinical treatment. The electron beam width at the scattering foil position was then evaluated using the full width at half maximum of the Gaussian distribution approximated from each one dimensional distribution of the irradiated radiochromic film. Results: The electron beam width at the scattering foil position was found to be 3.1 to 6.4 mm in the crossline direction and 2.8 to 5.5 mm in the inline direction with electron energy of 4 to 16 MeV. The two-dimensional distribution of the electron beam was therefore elliptical or distorted in shape, not circular. Conclusions: Direct measurement of the electron beam width at the scattering foil in the carrousel of a medical linear accelerator is possible, though the use of lower sensitivity film in addition to indirect methods is expected to bring about better results. However, as this method does not allow for direct measurement of the incident angle of the accelerated electron beam, further improvements and refinements are still needed.

DESIGN AND FABRICATION OF HIGH-PERFORMANCE INFRARED HOLLOW FIBER FOR MEDICAL LASER POWER DELIVERY

We proposed a method to evaluate the material dispersion of the dielectric film in dielectriccoated silver hollow fiber.By taking into consideration the derived material dispersion,the wavelengths of the loss peaks and valleys in the loss spectra of the hollow fiber can be predicted more accurately.Then,we fabricated the dielectric-coated silver hollow fiber according to the parameters obtained by using the improved design method.The measured data showed good agreement with the calculated results.The loss for medical laser of Er:YAG and CO_(2)was less than 0.3 dB/m.The loss for green or red pilot beams was around 5 dB/m,which is sufficiently low for the purpose of pilot beam transmission.The derived material dispersion plays an important role in the design and fabrication of the hollow fiber for multiwavelength delivery.

生物可降解塑料的发展与应用

目前,生物可降解塑料已取得较为突出的成绩和效果,但仍存在着需要改进的地方。随着生物基可生物降解塑料的前沿正在不断扩大,改进生物塑料的持续进展使其在工业应用中得到更多的应用。生物可降解塑料已有效地应用于某些方面中,例如生物可降解塑料被应用于食品生产包装、3D打印、农业地膜、医疗应用等方面。文章简要介绍了生物可降解塑料研究进展以及生物降解塑料研究中的新兴和先进技术、最新应用、未来方向及其在可持续发展中的作用。

E-FILM软件在核医学科图像存储中的应用

应用E-FILM工作站软件,对既往核医学科图像存储方式进行改进,使图像存储方法更科学、更合理。

医用钛表面石墨烯薄膜的PECVD法制备及其性能

目的在医用钛表面制备石墨烯薄膜,研究生长时间对石墨烯薄膜理化性能和生物学性能的影响。方法采用等离子体增强化学气相沉积设备,在医用钛表面制备石墨烯薄膜,控制石墨烯薄膜生长时间为5、10、30 min。通过拉曼光谱、扫描电子显微镜、接触角测量仪和电化学工作站对石墨烯薄膜的结构、表面形貌、表面润湿性和耐腐蚀性进行表征,通过小鼠成骨细胞培养评价石墨烯薄膜的细胞相容性。结果薄膜的拉曼结果呈现石墨烯的D、G和2D特征峰。生长时间为10 min和30 min的石墨烯薄膜在医用钛表面呈现垂直纳米片状态。随着生长时间的延长,医用钛表面石墨烯薄膜的水接触角逐渐增大。3组样品中,生长时间为5 min的样品具有最小的腐蚀电流密度(1.822×10^(‒7)A/cm^(2)),生长时间为10 min的样品具有最高的腐蚀电位(‒0.404 V);生长时间为5 min和10 min的样品有利于细胞的黏附与铺展,生长时间为30 min的样品对小鼠成骨细胞活性具有一定的抑制作用。结论石墨烯薄膜可以有效提高医用钛的耐腐蚀性。石墨烯薄膜生长时间影响其形貌,进而改变水接触角。不同生长时间的石墨烯薄膜对小鼠成骨细胞的黏附和铺展表现出明显的差异。

融合影片观摩的新型临床带教模式示例

目的通过融合影片观摩的新型临床带教模式示例,本研究旨在示范并推广一种创新的医学教育方法,即医学电影教学模式(film-based medical education mode)。方法2021年3月,本研究结合电影《Brain on Fire》(中文翻译为“脑火”)介绍了NMDA脑炎(NMDA encephalitis)的相关知识,为进一步推广该模式打下了基础。带教学员为神经内科本科室住院医师、外单位进修医师、其他科室轮转住院医师、主治医师、神经内科病房护士等共13位。由神经内科高年资主治医师主持,与护理部合作安排场地和制定计划,组织观看电影(影片全程1.5 h),观影结束后对影片介绍的疾病做一个简短的总结讲座。教学活动结束后通过填写《医学影片观摩教学反馈表》及时反馈。结果各项反馈指标显示该教学活动达到了预期的效果,反馈“非常满意”的比例达到84.6%。结论医学电影教学模式在各类型学员中反响很好,简单易行,目前该教学方法在国内医学院校中尚未普及,建议在临床教学实践中进一步推广。

人工智能在医学影像学辅助诊疗中的发展及应用研究新进展

医学影像学检查作为临床上常用的诊疗方法,能反映人体组织器官的形态及功能,在临床疾病的诊断及预后中发挥了重要的作用。临床上,对于医学影像的诊疗更多依赖于医生阅片,虽然能满足诊疗所需,但是受医生的经验及主观因素的影响,导致诊断结果存在偏差,亦增加医生工作量。人工智能(AI)是指任何能够感知和理解其周围环境,采取相应适当行动,最大限度实现其目标的代理或设备。因此,AI具有机器及智能设备的特点,能根据相应的数据自动预测计算,实现自主学习。利用AI技术用于医学影像学诊断中,能提升医生的准确性和效率,为患者提供更好的医疗服务。本综述将以医学影像学为起点,分析AI在医学影像学诊疗中的作用,探讨该方法在常用影像学中的价值及优点,为患者诊疗提供新方法。

医用镁合金微弧氧化工艺研究进展

从火花放电方面归纳整理了镁合金微弧氧化膜层的形成机理,并分析了膜层结构。在此基础上,结合国内外研究现状,阐述了预处理、电解质和添加剂以及电参数(电压、电流模式和脉冲频率)和封孔技术对镁合金微弧氧化膜层耐蚀性和生物相容性的影响。着重分析了电解质和添加剂的种类、浓度对膜层和生物性能的影响机制,其中电解质包括碱性硅酸盐和磷酸盐电解液等,添加剂包括甘油、氟化物、羟基磷灰石和纳米粒子等。研究发现,碱性磷酸盐电解质的加入可以降低膜层腐蚀速率,促进骨整合和细胞附着过程,羟基磷灰石、Ca、P等具有生物活性和对人体有益的粒子作为添加剂加入,可以显著提高膜层的耐蚀性和生物相容性。最后,基于研究现状,对镁合金微弧氧化技术在生物医用方面的发展进行了展望。

一种结合三重注意力机制的双路径网络胸片疾病分类方法

近年来,利用CNN进行医学图像处理,在胸片疾病分类任务中取得显著研究进展。然而,与单一结构CNN相比,双路径网络可结合不同CNN特点,从而提高疾病分类能力。其次,对于不同疾病,其位置、大小、形态、密度、纹理等特征均有不同,而注意力机制有助于模型提取不同病理特征,提升分类精度。因此针对胸片疾病分类问题,该文提出一种结合三重注意力机制的双路径卷积神经网络(TADPN),TADPN将ResNet和DenseNet结合的双路径网络DPN作为骨干网络,并利用3种不同形式的注意力机制改进DPN,在维持参数量稳定的同时提高网络复杂度,进而提升对胸片疾病的分类精度。在ChestXray14数据集上实验,并与目前较为先进的6种算法对比,14种疾病的平均AUC值达到0.8185,较前人提升1.1%,表明双路径CNN及三重注意力机制对胸片疾病分类的有效性及TADPN的先进性。

GB/T 42067-2022《水溶性生物降解医用织物包装膜袋》标准解读

国家标准GB/T 42067-2022《水溶性生物降解医用织物包装膜袋》已于2022年10月12日正式发布。本文简述了该标准的制定背景和国内外相关标准情况,介绍了标准的整体架构,并对标准中核心技术指标进行解读,旨在为标准使用者提供一定的参考依据。

多学科协作模式引入医学影像学实习生教学的应用探讨

目的 以实习大纲和教材为参考,探讨多学科协作(multidisciplinary collaboration,MDT)模式在医学影像学实习生教学的应用。方法 选择在宜昌市第二人民医院2018年8月—2021年8月医学影像科实习的大学本科生40名,将实习生随机分为试验组与对照组,对照组采取课堂教学,试验组采用MDT教学模式,对比分析教学时长、学生理论成绩、阅片成绩及无记名调查问卷结果。问卷调查的内容包括学习兴趣、文献阅读能力、教学满意程度、影像阅片分析以及临床思维能力。结果教学时长试验组较对照组更长,差异有统计学意义(P<0.05),理论成绩试验组高于对照组,差异有统计学意义(P<0.05),阅片成绩试验组高于对照组,差异有统计学意义(P<0.05),学习兴趣、文献阅读能力、教学满意程度、影像阅片分析以及临床思维能力试验组均优于对照组,差异有统计学意义(P<0.05)。结论 MDT教学模式在提高学生理论及阅片成绩方面有明显优势,在学习兴趣、文献阅读能力、教学满意程度、影像阅片分析以及临床思维能力方面也对学生有较大帮助,但是由于MDT教学模式需要多位临床带教老师的共同参与,以及涉及多学科的理论知识及临床专家的发言、讨论,因此教学时间相对较长。

医院使用云胶片替代传统医用胶片的效益分析

目的通过分析民航总医院使用云胶片替代传统医用胶片所带来的经济效益和社会效益,为今后医院使用云胶片提供数据支撑和科学依据。方法利用民航总医院2019年医院信息系统(hospital information system,HIS)统计数据库,应用Excel软件对数据进行统计分析。结果使用云胶片后,医院的耗占比下降0.72%,患者胶片费用平均降费49.40元/人次,降费比例为71.18%,其中做CT和磁共振检查的患者胶片降费比例分别为78.26%和83.71%。结论相较于传统医用胶片,云胶片的使用能够降低医院的耗材支出,降低患者就医费用。

普及公共卫生安全基础教育 树立公众科学防疫观念——以《人类与传染病的抗争--流感》科普教育专题片为例

医学类科普视频可以将科学家在医学实践过程中总结出来的知识经验传播给公众,旨在提升公众健康风险意识、树立科学防控观念。以《人类与传染病的抗争——流感》科普专题片为例,通过对该影片经验的总结,证实公众印象中艰深难懂的医学知识也可以通过科普专题片的方式变得“亲民”,并力求在常见型传染病来袭时,为公众提供一份具备充分参考和实用价值的“防疫说明书”,发挥医学专题中的科普作用。

水溶性PVA载体薄膜应用的现状与展望

主要介绍了水溶性PVA载体膜的特性,以及水溶性PVA作为载体膜在水转印和纺织刺绣、药膜、洗手膜等方面的应用,并对PVA载体膜作了展望。

水溶性PVA载体薄膜应用的现状与展望

本文主要介绍了水溶性PVA载体膜的特性,以及水溶性PVA作为载体膜在水转印和纺织刺绣、药膜、洗手膜等上的应用,并对PVA载体膜作了展望。

壳聚糖的成膜性及其工业应用进展

综述了壳聚糖的结构及成膜材料的组成与膜性质的关系,简要讨论了壳聚糖的脱乙酰化度、交联度与相对分子量的大小等内在结构因素,以及成膜时的pH、增塑剂的类型和浓度、其它高分子材料与膜的存放时间等外界成膜条件对壳聚糖膜的通透性、柔顺性、抗拉强度等性质的影响。介绍了天然壳聚糖资源及壳聚糖膜在食品保鲜、医疗及膜分离等方面的应用进展,从而展示其研究开发的广阔前景。