MSCT参数优化和图像质量的相关性研究

目的探讨多层螺旋CT（MSCT）诸扫描参数对图像质量的影响，以进一步提高MSCT图像的质量。方法固定扫描条件，分别对两种不同密度材料的质量控制体模进行扫描。在质量控制体模的左、中、右各选取1个431．43mm2的感兴趣区（ROI），改变其中某个扫描条件（如层厚、电压、曝光量、螺距），对质量控制模各扫描10次，计算CT值（X±SD），并比较各条件下两种质量控制体模的CT值。结果在固定扫描条件下，随曝光量、层厚的增加，CT图像对应各材料的平均CT值变化不明显，而SD明显减小；随着管电压的升高，CT图像对应各材料的平均CT值和SD明显减小；随着螺距的增大，CT图像对应各材料的平均CT值无明显变化，而SD增加较为明显。结论CT图像质量与扫描参数密切相关，并且各扫捕参数之间既相互影响，又相互制约。     

A Modular Activation/Coherence Approach to Evaluating Clinical/QEEG Correlations and for Guiding Neurofeedback Training: Modular Insufficiencies,Modular Excesses,Disconnections, and Hyperconnections

ABSTRACT

Current approaches to QEEG-guided neurofeedback involve efforts to normalize the abnormalities seen, without reference to the functional localization of the cortical areas involved. Recent advances in cortical neurophysiology indicate that specific brain areas are developed to perform certain functions (cortical modules). Complex brain functions require cooperation between modules, particularly during a learning situation. For example, the left prefrontal “activation module” must cooperate with one or both occipital “visual modules” to attend and see something on a chalkboard. To remember what has been seen, both temporal “memory modules” must cooperate with the visual modules for the image to be retained in short-term memory. If the connections between these modules are not functioning optimally, visual learning will be impaired. Decreased coherence (hypocoherence) indicates a decrease in functional connectivity between these modules, and increased coherence (hypercoherence) indicates an increase in functional connectivity between the modules. Neurofeedback can be used to normalize coherence between these modules, thereby improving the efficiency of their cooperation in the learning process. If coherence is less than normal, it is trained up. If coherence is more than normal, it is trained down. Three cases are presented where this approach has succeeded in remediating the client's symptoms.     

Does Scalp Cooling Have the Same Efficacy in Black Patients Receiving Chemotherapy for Breast Cancer?

Lessons Learned

• Despite U.S. Food and Drug Administration approval to reduce alopecia, data on efficacy of scalp cooling in Black patients with cancer are limited by lack of minority representation in prior clinical trials.
• Scalp cooling devices may have less efficacy in Black patients; additional studies are required to explore the possible causes for this, including hair texture and cap design.

BackgroundThe Paxman scalp cooling (SC) device is U.S. Food and Drug Administration (FDA)‐approved for prevention of chemotherapy‐induced alopecia. Studies report 50%–80% success rates and high patient satisfaction, yet there have been no studies of SC in Black patients. We conducted a phase II feasibility study of Paxman SC with a planned enrollment of 30 Black patients receiving chemotherapy for stage I–III breast cancer.MethodsBlack patients who planned to receive at least four cycles of chemotherapy with non‐anthracycline (NAC) or anthracycline (AC) regimens were eligible. Alopecia was assessed by trained oncology providers using the modified Dean scale (MDS) prior to each chemotherapy session. Distress related to alopecia was measured by the Chemotherapy Alopecia Distress Scale (CADS).ResultsFifteen patients enrolled in the intervention before the study was closed early because of lack of efficacy. Median MDS and CADS increased after SC, suggesting increased hair loss (p < .001) and alopecia distress (p = .04). Only one participant was successful in preventing significant hair loss; the majority stopped SC before chemotherapy completion because of grade 3 alopecia (>50% hair loss).ConclusionSC may not be efficacious in preventing alopecia in Black women. Differences in hair thickness, hair volume, and limitations of cooling cap design are possible contributing factors.     

医疗器械检测和校准实验室设备信息化管理的设计与开发

目的:研发实验室信息管理系统仪器设备数据库,实现检测与校准仪器的信息化管理。方法:在研究国家标准"GB/T27025-2008检测和校准实验室能力的通用要求"的基础上,运用编程语言Delphi7.0和微软SQL Server 2000开发后台数据库,分析其中涉及实验室设备管理、量值溯源等要素。结果:获取到所需要的数据字段和程序流程,完成功能模块数据库的集成。结论:在符合国家标准质量体系要求的前提下,建立检测和校准实验室仪器设备信息化管理的基础架构。     

Heat Conduction in a Functionally Graded Plate Subjected to Finite Cooling/Heating Rates: An Asymptotic Solution

This work investigates transient heat conduction in a functionally graded plate (FGM plate) subjected to gradual cooling/heating at its boundaries. The thermal properties of the FGM are assumed to be continuous and piecewise differentiable functions of the coordinate in the plate thickness direction. A linear ramp function describes the cooling/heating rates at the plate boundaries. A multi-layered material model and Laplace transform are employed to obtain the transformed temperatures at the interfaces between the layers. An asymptotic analysis and an integration technique are then used to obtain a closed form asymptotic solution of the temperature field in the FGM plate for short times. The thermal stress intensity factor (TSIF) for an edge crack in the FGM plate calculated based on the asymptotic temperature solution shows that the asymptotic solution can capture the peak TSIFs under the finite cooling rate conditions.     

对国内外几种玻璃纤维根管桩的力学性能评价

目的比较国内外4种玻璃纤维根管桩材料的力学性能,为国产玻璃纤维桩的研究和临床运用提供理论依据。方法选取FIBIO GLASSFIBER POST 9支、MATCHPOST 10支、LuxaPost 10支及国产玻璃纤维桩9支,采用三点加载系统测定其弯曲强度及弹性模量,并进行比较和统计分析。结果弯曲强度除MATCHPOST组与LuxaPost组、LuxaPost组与国产桩组无统计学差异外,其他各组间均有统计学差异(P0.05)。弹性模量除MATCHPOST组与LuxaPost组无统计学差异外,其他各组间均有统计学差异(P0.05)。LuxaPost的弯曲强度最大,FIBIO GLASSFIBER POST的弹性模量最低,与牙本质的弹性模量最接近。结论试验采用的4种玻璃纤维桩材料均体现出良好的力学性能,达到临床使用标准。     

基层老年护理培训班课程设计及评价

目的探讨基层老年护理培训班的课程设计、实施和评价。方法在文献调研的基础上,通过专家咨询形成基层老年护理培训班的七个培训模块;将培训课程应用于受日本笹川医学会专项经费援助的基层老年护理专业的护理人员,并对七个培训模块、30个课程进行效果评价。结果七个培训模块的需求评价和效果评价中老年护理安全评分最高,课程的评价中磁性护理文化、压力管理、老年患者的皮肤管理、预防老年人误吸以及老年人跌倒的管理排在前五位。结论护理人文建设和护理安全是基层老年护理工作者关注的热点。     

Vapor condensation with daytime radiative cooling

A radiative vapor condenser sheds heat in the form of infrared radiation and cools itself to below the ambient air temperature to produce liquid water from vapor. This effect has been known for centuries, and is exploited by some insects to survive in dry deserts. Humans have also been using radiative condensation for dew collection. However, all existing radiative vapor condensers must operate during the nighttime. Here, we develop daytime radiative condensers that continue to operate 24 h a day. These daytime radiative condensers can produce water from vapor under direct sunlight, without active consumption of energy. Combined with traditional passive cooling via convection and conduction, radiative cooling can substantially increase the performance of passive vapor condensation, which can be used for passive water extraction and purification technologies.

Energy and clean water are global challenges that are intertwined in an unfavorable way: even in areas where water is abundant, energy may not be available to purify it for human use (1, 2). There has been strong interest in developing passive technologies to purify or harvest water without using fuel or electricity. In this context, passive vapor condensation becomes particularly important because many passive water technologies go through the vapor phase of water in their harvesting or purification processes.Traditional vapor condensation technique is based on convective and conductive heat exchange with ambient environments. This technique is widely used in systems with hot vapors (3–6). However, with ever-increasing emphasis on passive systems, there are many situations in which warm- or even room-temperature vapor needs to be effectively condensed, such as extracting water from atmosphere (7–9) and warm vapor generated from high-efficiency solar evaporation (10). For vapor at such temperatures, most traditional condensers fail. For this reason, there is a clear need for a condensation technique to complement traditional condensers.A different technique is based on radiative vapor condensation. Darkling beetles in the Namib desert (11) use this technique to collect water. Their bodies function as a cooling surface by shedding thermal energy through midinfrared (mid-IR) radiation toward a clear nighttime sky, generating dew from humid air. This mechanism is also used by commercial radiative dew condensers (7–9). However, neither Namib beetle nor existing dew condensers can operate in the daytime (7). Those nighttime radiative condensers are incompatible with many emerging water technologies that require 24 h operation or direct access to sunlight.Recently, Fan et al. showed that passive radiative cooling to subambient temperatures can be realized even during the daytime, by integrating a high-efficiency solar reflector with a high-emissivity thermal emitter in the mid-IR atmospheric transparency window (12). Using this work as a basis, here we demonstrate a daytime radiative condenser. Compared to existing radiative vapor condensers (7–9), our condenser can function even in the presence of sunlight, which is essential for integration into passive water-harvesting systems that mainly operate during daytime.