Dielectric measurement of cerebral water content using a Network Analyzer

Abstract

At present, no practical method exists for monitoring the progression and severity of cerebral oedema in a clinical setting on a continuous basis. In search for such a method[ we investigated the electrical characteristics of cerebral tissue at microwave frequencies to quantify cerebral oedema. The dielectric constants of normal and oedematous canine cerebral white matter were measured using a Network Analyzer and then compared to the tissue's water content In additioni, salt infiltration and time elapsed after excision of the tissue were examined to determine their effects on the measurements.

The water content and dielectric constant of the white matter were linearly related (correlation coefficient; r = 0.903), comparable to results obtained with a Time Domain Reflectometer in previous research. The Network Analyzer, however; is a more robust measurement device and, because of this, can potentially be used for long term measurements. Further, it was found that neither an increased tissue salt content nor the amount of time after excision of the tissue significantly affected the results. This indicates that the dielectric constant of cerebral white matter is mainly a function of the tissue's water content     

场域论视域下高校学术期刊与主办高校的融合发展

【目的】 深入分析高校学术期刊在主办高校内部被边缘化的现状与成因,探索高校学术期刊与主办高校融合发展的对策路径。【方法】 以社会场域论为研究工具,对我国高校学术期刊与主办高校融合发展的现实困境与对策路径进行分析。【结果】 学术期刊与高等院校存在场域融合壁垒,高校学术期刊的发展既受限于主办高校的教学、科研、人力及行政管理,又要服从学术期刊的发展规律和出版业务部门管理,很难与主办高校的发展产生共振,难以深层融入主办高校的发展。【结论】 高校学术期刊与主办高校深度融合的发展路径包括：构建高校学术期刊与主办高校的协同发展网络,打破场域壁垒;改革经济资本走向,完善制度资本,优化人力管理资本;消除惯习误识,扬弃高校对学术期刊的定位依赖惯习。     

Immunization of Zika virus envelope protein domain III induces specific and neutralizing immune responses against Zika virus

In this study, we described the generation and immunogenicity of the Zika Virus (ZIKV) envelope protein (E) domain III (DIII) as a protein subunit vaccine candidate. ZIKV EDIII (zEDIII) was rapidly produced in E. coli in inclusion bodies. ZIKV EDIII was solubilized, refolded and purified to >95% homogeneity with a one-step Ni²⁺ affinity chromatography process. Further analysis revealed that zEDIII was refolded properly and demonstrated specific binding to an anti-zEDIII monoclonal antibody that recognizes a zEDIII conformational epitope. Subcutaneous immunization of mice with 25 and 50 μg of zEDIII was performed over a period of 11 weeks. zEDIII evoked ZIKV-specific and neutralizing antibody response with titers that exceed the threshold that correlates with protective immunity against ZIKV. The antigen-specific IgG isotypes were predominantly IgG1 and splenocyte cultures from immunized mice secreted IFN-gamma, IL-4 and IL-6. Notably, zEDIII-elicited antibodies did not enhance the infection of dengue virus in Fc gamma receptor (FcγR)-expressing cells. This study provided a proof of principle for the further development of recombinant protein-based subunit vaccines against ZIKV.     

个体参赌意愿跨情境特殊性分析

目的 评价个体在各类赌博情境中的行为倾向,探讨赌博类别这一情境性变量对参赌意愿的影响.方法 对373名澳门被试在13种博彩游戏中的参赌意愿进行问卷调查,并对所获取的参赌意愿数据进行探索性因素分析.结果 抽取出2个特征根大于1的因素,分别命名为低对弈性赌博和高对弈性赌博,两因素分别解释了 32.59%和26.86%的变异量,累积解释率为59.46%.被试在低对弈性赌博中的参赌意愿普遍偏低[(1.62±1.13)分～(2.20±1.35)分],而在高对弈性赌博中的参赌意愿则普遍偏高[(2.34±1.39)分～(3.02±1.55)分].结论 跨情境的特殊性不仅存在于一般的风险决策中,个体的参赌意愿也具有跨情境特殊性的特点,即各种博彩并非生来平等,参赌意愿较高的个体并非对所有博彩(赌博类别)的参赌意愿都高.     

胃癌患者血清RASSF1A基因启动子区甲基化检测

Ras相关结构域家族1A（RASSF1A）基因是近年发现的新型抑癌基因，其启动子区甲基化可能与胃肠道肿瘤的发生、发展密切相关。目的：检测胃癌患者血清RASSF1A基因启动子区甲基化情况，探讨其在胃癌早期诊断和预后评估中的可能作用。方法：以甲基化特异性聚合酶链反应（MSP）检测47例胃腺癌患者、30例胃良性病变患者和30名健康对照者的血清RASSF1A基因启动子区甲基化情况，其中16例胃腺癌患者同时留取手术切除癌组织、癌旁组织标本以及术前、术后血标本行对照研究。结果：胃腺癌患者血清RASSF1A基因启动子区甲基化率为34．0％（16／47），显著高于胃良性病变患者（3.3％，1／30）和健康对照者（0％）（P〈0．01）。16例胃腺癌组织中5例（31．2％）检测到RASSF1A基因启动子区甲基化，其中4例（80．0％）术前、术后血清标本均检测到RASSF1A基因启动子区甲基化。血清RASSF1A基因启动子区甲基化与胃癌患者性别、年龄、肿瘤分化程度、有无转移以及血清癌胚抗原（CEA）水平均无相关性。结论：血清RASSF1A基因启动子区甲基化检测可望为胃癌的早期诊断和预后判断提供依据。