Simultaneous purification of minor components in natural products using twin-column recycling chromatography with a step solvent gradient

The isolation of minor components from complex natural product matrices presents a significant challenge in the field of purification science due to their low concentrations and the presence of structurally similar compounds.This study introduces an optimized twin-column recycling chromatography method for the efficient and simultaneous purification of these elusive constituents.By introducing water at a small flowing rate between the twin columns,a step solvent gradient is created,by which the leading edge of concentration band would migrate at a slower rate than the trailing edge as it flowing from the upstream to downstream column.Hence,the band broadening is counterbalanced,resulting in an enrichment effect for those minor components in separation process.Herein,two target substances,which showed similar peak position in high performance liquid chromatography(HPLC)and did not exceed 1.8%in crude paclitaxel were selected as target compounds for separation.By using the twin-column recycling chromatography with a step solvent gradient,a successful purification was achieved in getting the two with the purity almost 100%.We suggest this method is suitable for the separation of most components in natural produces,which shows higher precision and recovery rate compared with the common lab-operated separation ways for natural products(thin-layer chromatography and prep-HPLC).

Packed Supercritical Fluid Chromatography for the Analyses and Preparative Separations of Palm Oil Minor Components

This paper depicts a brief review on the applications of packed supercritical fluid chromatography (SFC) in palm oil analyses and purifications from early 1990s to date. Packed SFC has been used for the analyses of various palm oil components. The analytical separations have also been scaled up to preparative scale that leads to the recovery of high value components from palm oil. This review encompasses both analytical and preparative SFC in the oil palm processing.

Determination of potassium content as principal components in pyrotechnic compositions used for fireworks and firecrackers based on inductively coupled plasma optical emission spectrometric approach （ICP-OES）

Inductively coupled plasma optical emission spectrometric approach（1CP-OES） is used to determine the potassium content as principal component in pyrotechnic compositions used for fireworks and firecrackers. Element of potassium is conunonly found in potassium nitrate and potassium perchlorate in pyrotechnic compositions in fireworks and firecrackers. Statistical analysis shows that potassium nitrate content in pyrotechnics is between 10% to 60% and the potassium perchlorate content is between 20% to 70%,which counted in the content of potassium element is between 4% to 23%. Concept of this method： considering the weight of the sample is 400rag,constant volume is 1L and the concentration of potassium is between 10 mg/L to 90 mg/L in sample solution, the determination scope of the method for the potassium content would be between 1% to 23%.Further experiments proved that the fitting correlation coefficient of potassium calibration curve is 0.9997 or higher, recovery is 89.15%-100.23%.The allowable differential value is 0.4% between two single tests under repeatable conditions. This method can completely satisfy the requirements of the fireworks and firecrackers industry with high accuracy and good precision.

Determination of magnesium and aluminum content as principal components in pyrotechnic compositions used for fireworks and firecrackers based on inductively coupled plasma optical emission spectrometric approach （ICP-OES）

Inductively coupled plasma optical emission spectrometric approach（ICP-OES）is used to determine the magnesium and aluminum content as principal components in pyrotechnic compositions used for fireworks and firecrackers. Elements of magnesium and aluminum are commonly found in aluminum powder or magnesium-aluminum alloy powder in pyrotechnic compositions in fireworks and firecrackers. Statistical analysis shows that the magnesium content in pyrotechnics is between 8% to 30% and the aluminum content is between 8% to 35%（roughly）.Concept of this method： suppose the weight of the sample is 400rag,constant volume is IL and the concentlation of magnesium and aluminum is between 12mg/L to 160mg/L in sample solution, the determination scope of the method for magnesium and aluminum content would be between 3% to 40%.Further experiments proved that the fitting correlation coefficient of the magnesium calibration curve is 0.9999 or higher, recovery is 101.01% -101.96%.The fitting correlation coefficient of the aluminum calibration curve is 0.9999 or higher, recovery is 99.36%-103.07%. The allowable differential value is 0.4% between two single tests under repeatable conditions. This method can completely satisfy the requirements of the fireworks and firecrackers industry with high accuracy and good precision.

Determination of Active Components of Lamiophlomis rotata(Benth.)Kudo by Ultra-performance Convergence Chromatography

[Objectives]To determine active components of Lamiophlomis rotata(Benth.)Kudo.[Methods]A new method was developed for the quantitative determination of L.rotata by using Ultra-performance convergence chromatography.The separation of active components of L.rotata was successfully achieved on Waters ACQUITY UPC column,with gradient elution carbon dioxide and methanol solvent at flow rate of 0.7 mL/min.The separation gradient elution rate was as follows:15%methanol 0-1 min,18%methanol 1-5 min,20%methanol 5-6 min,25%methanol 6-7 min,30%methanol 7-8 min,30%methanol 8-9 min,15%methanol 9-10 min.The conditions used in the separation process was as follows:column temperature 30℃;injection volume 2μL.Under the abovementioned conditions,the content of methyl glucoside was measured by 3D-full wavelength scanning.The validity of the method was tested by analyzing the precision,reproducibility,stability and accuracy.[Results]The results indicated that in terms of extraction and separation of compounds,supercritical CO2 not only has the diffusion property of gas,but also has the density and fluidity of liquid.[Conclusions]The ultra-high performance chromatography is a new technique for drug analysis.

Simultaneous Spectrophotometric Determination of Four Components including Acetaminophen by Taget Factor Analysis

UV Spectrophotometric Target Factor Analysis （TFA） was used for the simultaneous determination of four components （acetaminophen, guuaifenesin, caffeine, Chlorphenamine maleate） in cough syrup. The computer Frogram of TFA is based on VC＋＋ language. The difficulty of overlapping of absorption spectra of four compounds was overcome by this procedure. The experimental results show that the average recovery of each component is all in the range from 98.9% to 106.8% and each component obtains satisfactory results without any pre-separation.

Simultaneous Biparametric Determination of Total Calcium and Potassium in Biological Fluids by Flow Injection Analysis──Use of Powell＇s Method in the System Optimization

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Progress and prediction of multicomponent quantification in complex systems with practical LC-UV methods

Complex systems exist widely,including medicines from natural products,functional foods,and biological samples.The biological activity of complex systems is often the result of the synergistic effect of multiple components.In the quality evaluation of complex samples,multicomponent quantitative analysis(MCQA)is usually needed.To overcome the difficulty in obtaining standard products,scholars have proposed achieving MCQA through the“single standard to determine multiple components(SSDMC)”approach.This method has been used in the determination of multicomponent content in natural source drugs and the analysis of impurities in chemical drugs and has been included in the Chinese Pharmacopoeia.Depending on a convenient(ultra)high-performance liquid chromatography method,how can the repeatability and robustness of the MCQA method be improved?How can the chromatography conditions be optimized to improve the number of quantitative components?How can computer software technology be introduced to improve the efficiency of multicomponent analysis(MCA)?These are the key problems that remain to be solved in practical MCQA.First,this review article summarizes the calculation methods of relative correction factors in the SSDMC approach in the past five years,as well as the method robustness and accuracy evaluation.Second,it also summarizes methods to improve peak capacity and quantitative accuracy in MCA,including column selection and twodimensional chromatographic analysis technology.Finally,computer software technologies for predicting chromatographic conditions and analytical parameters are introduced,which provides an idea for intelligent method development in MCA.This paper aims to provide methodological ideas for the improvement of complex system analysis,especially MCQA.

基于UPLC-Q-TOF-MS技术建立银花抗病毒口服液的指纹图谱及多指标含量测定

目的建立银花抗病毒口服液的UPLC-Q-TOF-MS指纹图谱,对其主要化学成分进行分析鉴定,并测定6个化学成分的含量。方法采用UPLC-Q-TOF-MS技术,正、负离子模式,Agilent ZORBAX Eclipse Plus C18(3.0 mm×100 mm,1.8μm)色谱柱,以水相(A,含0.1%甲酸)和有机相乙腈(B)为流动相梯度洗脱,流速为0.4 mL·min^(-1),进样量为1μL。建立12批银花抗病毒口服液的指纹图谱,确定共有峰并进行相似度评价、聚类分析、主成分分析和偏最小二乘判别分析,通过一级、二级质谱及对照品比对鉴别共有峰的化学成分。结果在正、负离子模式下共鉴定了12批银花抗病毒口服液的指纹图谱,确定共有峰32个,指纹图谱相似度均≥0.978,通过聚类分析将样品各分为4类、3类,与主成分分析一致,筛选出汉黄芩苷、千层纸素A苷、连翘酯苷I、异绿原酸B等8个成分是导致不同批次样品差异的标志性化合物。结论所建立的指纹图谱结合多指标含量测定方法稳定、重复性好、特征性强,可为银花抗病毒口服液的质量评价和临床应用提供有效参考。

Minor Component Analysis-based Landing Forecast System for Ship-borne Helicopter

The general structure of ship-borne helicopter landing forecast system is presented, and a novel ship motion prediction model based on minor component analysis (MCA) is built up to improve the forecast effectiveness. To validate the feasibility of this landing forecast system, time series for the roll, pitch and heave are generated by simulation and then forecasted based on MCA. Simulation results show that ship-borne helicopters can land safely in higher sea condition while carrying on rescue or replenishment tasks at sea in terms of the landing forecast system.

Diabetes in migrants and ethnic minorities in a changingWorld

On a worldwide scale, the total number of migrants exceeds 200 million and is not expected to reduce, fuelled by the economic crisis, terrorism and wars, generating increasing clinical and administrative problems to National Health Systems. Chronic non-communicable diseases(NCD), and specifically diabetes, are on the front-line, due to the high number of cases at risk, duration and cost of diseases, and availability of effective measures of prevention and treatment. We reviewed the documents of International Agencies on migration and performed a Pub Med search of existing literature, focusing on the differences in the prevalence of diabetes between migrants and native people, the prevalence of NCD in migrants vs rates in the countries of origin, diabetes convergence, risk of diabetes progression and standard of care in migrants. Even in universalistic healthcare systems, differences in socioeconomic status and barriers generated by the present culture of biomedicine make high-risk ethnic minorities under-treated and not protected against inequalities. Underutilization of drugs and primary care services in specific ethnic groups are far from being money-saving, and might produce higher hospitalization rates due to disease progression and complications. Efforts should be made to favor screening and treatment programs, to adapt education programs to specific cultures, and to develop community partnerships.

Distribution of the Sample Correlation Matrix and Applications

For the case where the multivariate normal population does not have null correlations, we give the exact expression of the distribution of the sample matrix of correlations R, with the sample variances acting as parameters. Also, the distribution of its determinant is established in terms of Meijer G-functions in the null-correlation case. Several numerical examples are given, and applications to the concept of system de- pendence in Reliability Theory are presented.

Prevalence of influenza vaccination coverage amongst the first and third generation Asian adults in California, United States of America

The Asian population comprises the third largest ethnic minority in the state of California.However,influenza vaccination coverage amongst the overall Asian population,and the first and third-generation Asian’s have not been widely studied.Previous literature exploring generational status as a corelate of influenza immunization amongst Mexican identified Latino adults confirms disparities in influenza vaccination coverage by generation.This study aims to report on the prevalence of influenza vaccination coverage amongst the overall,first and third-generation Asians in California,and examine the correlates of influenza vaccination coverage in the aforementioned population.Methods:Cross-sectional data from the California Health Interview Survey 2016 for Asian adults was analyzed using IBM SPSS 25.0 for Mac.Descriptive statistics were utilized for reporting the frequencies and percentages of the selected variables.Weighted multivariable binary logistic regression was used to obtain adjusted odds ratios(95%confidence interval)and determine independent association between socioeconomic determinants and influenza vaccination coverage amongst the first and third-generation Asians at P<0.05.The analysis was adjusted for“visit to the doctor”and“insurance status”.Results:Thirteen point one percent(n=2,761)of the survey respondents(N=21,055)identified as Asians.The first-generation(n=1,857,67%)comprised the highest proportion of the Asian ethnic group.Influenza vaccination coverage was reported as 61.2%amongst the overall,61.1%amongst the first-generation and 70.9%amongst the third-generation respectively.All predictor variables were significant amongst the first-generation,however amongst the third-generation all variables except for location and living in a household of 3 and more,were significant predictors of influenza vaccination coverage.Conclusion:Compared to the other ethnic groups in California,the Asian respondents reported a higher percentage of influenza vaccination coverage.Influenza vaccination coverage was the highest amongst the third-generation Asians.Increased influenza vaccination coverage amongst the Asian ethnic group can be ascribed to higher educational attainment,a higher proportion choosing to visit a doctor as well as increased insurance coverage.

Cardiovascular diseases in European ethnic minorities: Beyond the traditional cardiovascular risk factors

This editorial is intended to be a reflection on cardiovascular disease(CVD)burden in European ethnic minorities.In some European countries,ethnic minority realities,due to their recent appearance,are still to be studied in depth.The experience of several European countries,where the migration processes started earlier,even more than a century ago,can help by being an example.Many studies have shown that major differences in CVD burden exist not only between countries,but also within the same country when considering different social strata and ethnic groups.The CV risk factors underlying heart disease have been well established.Important epidemiological studies have helped us understand that the underlying causes of heart disease as well as the behaviors that can help prevent them are the same.We are now well aware that CVD should be treated by considering a holistic approach.This is why the social determinants(SDs)of health that may worsen the disease burden or that,vice versa,may improve the treatment,and even more significantly,the prognosis of a patient’s illness should be taken into consideration.For ethnic minority patients,this holistic,hermeneutic approach is of importance.Several SDs of health that influence CVDs have been identified but their relevance for the health of ethnic minorities has not yet been clearly defined.In some European countries,most ethnic minorities are largely also religious minorities.Only a few studies have evaluated the role of religion,which is an important SD that affects the probability of having CV risk factors and diseases.Adolescents,particularly those belonging to the second generation,seem to be the weak link.If we believe that these young people are really citizens of their country of birth,then a way of recognizing their belonging to the community starts from a will to better understand their condition,in order to assist them while they grow physically and mentally.Thinking about safeguarding the health of this population should be more than a health task,rather a goal of social justice.

基于GC×GC-TOFMS和化学计量学的典型浓香型白酒鉴别分析

为了研究典型浓香型白酒的差异性,利用全二维气相色谱飞行时间质谱联用仪(GC×GC-TOFMS)、气相色谱-氢火焰离子检测器(GC-FID)结合定性定量技术手段研究了不同地域和品牌的浓香型白酒的挥发性风味组分。基于挥发性风味组分和色谱骨架成分,通过正交偏最小二乘判别分析(OPLS-DA)对不同产地的浓香型白酒进行区分鉴别,且预测能力指数Q2Y值均大于0.5,具备较好的预测能力。基于挥发性风味组分筛选出庚酸乙酯、4-壬醇、水杨酸甲酯、3,5-二甲基-4-辛酮、4-壬酮、乙醛乙基己基缩醛等49个VIP值大于1.5的潜在差异性化合物用以鉴别不同地域的浓香型白酒。

Simultaneous Determination of Seven Components in Gamboge and Its Processed Products Using a Single Reference Standard

Objective To establish a quality control method for simultaneous determination of multiple components in gamboge. Methods A single reference standard for the determination of multiple components （SSDMC） with HPLC was proposed. Seven major components of gamboge including gambogenic acid （S）, β-morellic acid （C1）, 2R-30-hydroxygambogic acid （C2）, isogambogenic acid （C3）, gambogellic acid （C4）, 2R-gambogic acid （C5）, and 2S-gambogic acid （C6） were simultaneously analyzed using gambogenic acid as reference standard. The credibility and feasibility of SSDMC method were validated with respect to linearity, limits of detection and quantification, precision, stability, repeatability, accuracy, ruggedness, and robustness. The relative conversion factors （RCFs） of S and C1-6 were calculated. Twelve batches of gamboge including crude and processed products were successfully analyzed by applying the SSDMC and traditional external standard （ES） methods. Results The SSDMC method was credible and feasible. The RCFs of S and C1-6 were 1.000, 0.913, 0.864, 1.064, 0.777, 0.921, and 0.919, respectively. No significant difference was observed in the contents of the seven components between SSDMC and ES methods. The heat-processing technique caused a reduction in the seven components. Conclusion SSDMC is a simple, reliable, and effective method for the analysis of the complex multiple components in gamboge, and it is also a practical and economical approach.

基于UPLC-Q-TOF-MS技术的脉络宁注射液酯提废渣大孔树脂富集液的化学成分鉴定和含量测定

目的利用超高效液相-四极杆串联飞行时间质谱(UPLC-Q-TOF-MS)技术分析脉络宁注射液酯提废渣的化学成分,为酯提废渣资源的再利用提供科学依据。方法利用ASD-7大孔树脂柱富集脉络宁注射液酯提废渣化学成分,采用UPLC-Q-TOF-MS技术对脉络宁注射液酯提废渣大孔树脂富集液进行数据采集和化学成分鉴定,采用定量软件对绿原酸、异绿原酸、异绿原酸C、灰毡毛忍冬皂苷甲和灰毡毛忍冬皂苷乙进行含量测定。结果共鉴定出脉络宁注射液酯提废渣中42个化学成分,包括9个酚酸类化合物、9个黄酮类化合物、10个环烯醚萜类化合物、8个三萜皂苷类化合物、5个苯丙素类化合物和1个联苄类化合物,定量分析结果显示绿原酸、异绿原酸、异绿原酸C、灰毡毛忍冬皂苷甲和灰毡毛忍冬皂苷乙在考察的浓度范围内与峰面积线性关系良好(r>0.9990),精密度、重复性和稳定性良好,加样回收率为95.38%~103.06%,RSD为0.76%~1.8%。结论本研究可用于脉络宁注射液酯提废渣大孔树脂富集液中化学成分的鉴定以及5种有效成分的准确定量分析,为脉络宁注射液酯提废渣的再利用和制备工艺奠定基础。

Population distribution in China-characteristics,components, determinants since 1949

Rational population distribution is an important issue in China. In depth analysis on population distribution is valuable for policy making. in this paper, an attempt is made to study changes in population distribution by region. province, rural-urban and city size in China. their components and determinants since 1949.

Key Social Determinants to Narrow the Gap between Health-adjusted Life Expectancy and Life Expectancy in Megacities

Objective Improvement in the quality of life is reflected in the narrowing of the gap between healthadjusted life expectancy(HALE)and life expectancy(LE).The effect of megacity expansion on narrowing the gap is rarely reported.This study aimed to disclose this potential relationship.Methods Annual life tables were constructed from identified death records and population counts from multiple administrative sources in Guangzhou,China,from 2010 to 2020.Joinpoint regression was used to evaluate the temporal trend.Generalized principal component analysis and multilevel models were applied to examine the county-level association between the gap and social determinants.Results Although LE and HALE in megacities are increasing steadily,their gap is widening.Socioeconomic and health services are guaranteed to narrow this gap.Increasing personal wealth,a growing number of newborns and healthy immigrants,high urbanization,and healthy aging have helped in narrowing this gap.Conclusion In megacities,parallel LE and HALE growth should be highly considered to narrow their gap.Multiple social determinants need to be integrated as a whole to formulate public health plans.

基于SMOTE-IKPCA-SeNet深度迁移学习的小批量生产质量预测研究

随着智能制造技术的发展和客户个性化需求的增加,多品种小批量生产方式逐渐成为制造业的主流。面向大批量生产、以统计过程控制为核心的质量管理方式并不适用于小批量生产。针对复杂生产过程存在参数多、非线性和交互作用的问题,提出利用深度迁移学习的方式将历史生产数据作为源域迁移至小样本目标产品数据进行质量预测。首先,通过合成少数类过采样技术(synthetic minority over-sampling technique,SMOTE)和改进的核主成分分析(improved kernel principal component analysis,IKPCA)算法筛选源域和目标域的可迁移特征,这不仅兼顾了特征重要性和可迁移性,还减少了“负迁移”,提高了模型泛化能力;然后,采用结合通道注意力机制的卷积神经网络SeNet构建基于深度迁移学习的质量预测模型。仿真结果表明,随着目标域样本的增加,所提方法的预测准确性明显优于广泛采用的支持向量机建模方法。同时,所提可迁移特征筛选方法显著提高了深度迁移学习的质量预测效果,为复杂的小批量生产过程质量保证提供了新方法。