开源软件社区中人类知识创造行为的个体差异性研究

近年来,利用复杂性科学解释人类行为成为一个新兴的研究热点.与以群体或群体中部分个体为研究对象不同,以codeplex开源软件社区所有个体知识创造行为为研究对象,利用人类行为动力学方法从活跃度、阵发性、时间间隔分布、长程相关性四个侧面对社区中所有个体知识创造过程中的生产行为、沟通行为、bug讨论行为进行分析.发现开源软件社区中生产者个体的这三种行为在活跃度、分布形式及分布参数、阵发性指标、长程相关性都呈现出显著的差异性.最后,对造成这种差异性的原因进行了讨论.     

基于RST/IAHP的航空维修人因可靠性评估模型研究

针对航空维修人因可靠性定量评估这一难点问题,提出了一种基于粗糙集理论(RST)和区间层次分析法(IAHP)的人因可靠性评估模型.根据大量统计数据,运用决策树法建立分层次的航空维修科目人因可靠性指标评价体系.综合采用区间层次分析法和粗糙集方法确定指标权重,提出了采用区间型加权算法对指标进行聚合.以某航空维修系统更换发动机科目为例,对所提方法进行案例验证.结果表明,该方法具有实用、可操作性强等特点,为航空维修系统科目的人因可靠性评估提供了理论参考.     

弘扬地方文化 优化课堂教学——将闽都文化融入中学化学教学

分析地方文化融入中学化学的重要性与必要性,整理闽都文化中涉及的化学知识。以脱胎漆器、茉莉花茶、糖画为例,进行化学教学应用的设计,提出促进地方文化更好地融入中学化学教学的建议,旨在促进学生人文底蕴、家国情怀的培养,科学精神、辩证思维的形成。     

A simple and easy non-derivatization gas chromatography-mass spectrometry method for simultaneous quantification of valproic acid,gabapentin, pregabalin,and vigabatrin in human plasma

Immunoassays are currently not available in commercial kits for the quantification of valproic acid, vigabatrin, pregabalin, and gabapentin, which also cannot suffer the limitations of interferences of substances with similar structures. Chromatography is a good alternative to immunoassay. In this study, a simple and robust non-derivatization gas chromatography-mass spectrometry method for simultaneous determination of the above four drugs in human plasma was developed and validated for therapeutic drug monitoring purposes. This method employed benzoic acid as the internal standard with hydrochloric acid for plasma acidification and ACN for precipitate protein. The supernatant was directly injected into gas chromatography-mass spectrometry for analysis. Good linearity was obtained with linear correlation coefficients of the four analytes of 0.9988–0.9996. Extraction recoveries of valproic acid, vigabatrin, pregabalin, and gabapentin were respectively in the ranges of 91.3%–94.5%, 90.0%–90.9%, 90.0%–92.1%, and 88.0%–92.2% with the relative standard deviation values less than 12.6%. Intra- and inter-batch precision and accuracy, and stability assays were all acceptable. Taken together, the novel method developed in this study provided easy plasma pretreatment, good extraction yield, and high chromatographic resolution, which has been successfully validated through the quantification of valproic acid in the plasma of 46 patients with epilepsy.     

Properties and biocompatibility of colloid cadmium sulfide nanoparticles

The properties and cytotoxicity of aqueous colloidal solutions of cadmium sulfide CdS nanoparticles obtained by chemical condensation were explored. Dynamic light scattering and optical spectroscopy were used to study the hydrodynamic diameter, size distribution, zeta-potential and optical properties of the CdS nanoparticles in solution. The cytotoxicity of colloidal CdS nanoparticles at different concentrations was assessed on cultures of human dermal fibroblasts and the cancer HeLa line.     

Determination of insulin aspart in plasma by liquid chromatography-quadrupole electrostatic field orbitrap high-resolution mass spectrometryEI北大核心CSCD

A rapid detection method for insulin aspart in human plasma was established by using liquid chromatography-quadrupole electrostatic field orbitrap high-resolution mass spectrometry. Samples were pretreated with a precipitant of methanol-acetonitrile-acetic acid solution (49:49:2, V/V/V), an Agilent Eclipse Plus C18 column (50 mm×2.1 mm, 3.5 µm) was selected, with 0.1% aqueous formic acid and 0.1% formic acid[1]acetonitrile as mobile phases for gradient elution, and mass spectrometry was performed in selected ions monitoring (SIM) scan mode. The experimental results showed that the linear relationship of insulin aspart in human plasma was good in the range of 0.1-10 µg/mL (R2=0.9938), with the limit of quantification of 0.1 µg/mL, and the limit of detection of 0.05 µg/mL. The recoveries ranged from 71.6% to 106.2%, and the relative standard deviations (RSDs) of the intra-day and inter-day were both less than 15%. The method can meet the inspection needs of actual cases. © 2023, Youke Publishing Co.,Ltd. All rights reserved.     

Analytical applications of Raman spectroscopy

In this article interaction of transition metal complexes with DNA and its applications in electrochemical DNA biosensors as hybridization indicator or electroactive marker of DNA are reviewed. Special emphasis has been given to the efforts for the development of new transition metal complexes and their interaction to DNA. DNA and polymers covalently conjugated with transition metal complexes were also reviewed.     

毛细管电泳等离子体原子发射光谱测定人血浆中游离钙离子的含量

毛细管电泳-电感耦合等离子体原子发射光谱联用技术应用于人体血浆中钙元素的形态分析,对游离钙离子进行了定位表征与定量分析。在电泳缓冲溶液为30 mmol/L Tris-HCl(pH=7.4)及电泳电压为20 kV的条件下,得到人体血浆中钙的主要形态有8种,其中一种为游离钙离子,迁移时间的相对偏差小于2%(n=10),血浆中游离钙离子的含量为42.2 mg/L,该测定方法RSD小于5%。采用以上联用技术测得血浆样品中游离钙离子回收率为94.8%~104%;方法检出限为25μg/L。     

A simple and sensitive HPLC method for quantitation of low phenoprolamine hydrochloride concentrations in human plasma and its pharmacokinetic application

Phenoprolamine hydrochloride is a novel compound that works against a variety of types of hypertension. The purpose of this study was to develop a simple and sensitive high-performance liquid chromatographic method for quantitation of low phenoprolamine hydrochloride concentrations in human plasma and to apply it to pharmacokinetic study. The procedure involved extraction of the drug and clonidine (internal standard) from the plasma using diethyl ether. Chromatographic separations were carried out on a 4.6 x 200 mm Hypersil silica column with UV detection at 230 nm. The isocratic mobile phase, 1% ammonium acetate (pH 5.4) and methanol (0.3:99.7, v/v), was run at 1 mL/min. Extraction recovery was 84% for phenoprolamine hydrochloride at a concentration level of 200 ng/mL, and 76% for clonidine at 200 ng/mL. The method was linear in the concentration range 5-4000 ng/mL with a lower limit of quantitation of 5 ng/mL for phenoprolamine hydrochloride. Inter- and intra-day coefficients of variation were less than 10%. The validated method was successfully applied to a pharmacokinetic study in human after an oral administration of the drug, and the pharmacokinetic parameters are presented.     

Development and validation of a sensitive LC-MS/MS method with electrospray ionization for quantitation of zafirlukast, a selective leukotriene antagonist in human plasma: application to a clinical pharmacokinetic study

A highly sensitive and specific LC-MS/MS method has been developed and validated for the estimation of zafirlukast (ZFK) with 500 microL human plasma using valdecoxib as an internal standard (IS). The API-4,000 LC-MS/MS was operated under multiple reaction-monitoring mode using the electrospray ionization technique. The assay procedure involved extraction of ZFK and IS from human plasma with ethyl acetate. The resolution of peaks was achieved with 10 mm ammonium acetate (pH 6.4):acetonitrile (20:80, v/v) on a Hypersil BDS C(18) column. The total chromatographic run time was 2.0 min and the elution of ZFK and IS occurred at approximately 1.11 and 1.58 min, respectively. The MS/MS ion transitions monitored were 574.2 --> 462.1 for ZFK and 313.3 --> 118.1 for IS. The method was proved to be accurate and precise at a linearity range of 0.15-600 ng/mL with a correlation coefficient (r) of >or=0.999. The method was rugged with 0.15 ng/mL as lower limit of quantitation. The intra- and inter-day precision and accuracy values were found to be within the assay variability limits as per the FDA guidelines. The developed assay method was applied to a pharmacokinetic study in human volunteers following oral administration of 20 mg ZFK tablet.