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Mass spectrometry detection of basic drugs in fast chiral analyses with vancomycin stationary phases

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Journal of Pharmaceutical Analysis 2018年第5期8卷 324-332页

作者： Hongyue Guo M.Farooq wahab Alain Berthod Daniel w.armstrong Department of Chemistry and Biochemistry University of Texas at Arlington Institut des Sciences Analytiques CNRS Université de Lyon 1

Current trends in chiral analysis of pharmaceutical drugs are focused on faster separations and higher separation efficiencies, Core-shell or superficially porous particles （SPP） based chiral stationary phases （CSPs） provide reduced analysis times while maintaining high column efficiencies and sensitivity. In this study, mobile phase conditions suitable for chiral analyses with electrospray ionization LC-MS were systematically investigated using vancomycin as a representative CSP. The performance of a 2.7 μm SPP based vancomycin CSP （SPP-V） 10 cm ×0.21 cm column was compared to that of a corresponding 5 μm fully porous particles based analogue column. The results demonstrated that the SPP-V column provides higher efficiencies, 2-5 time greater sensitivity and shorter analysis time for a set of 22 basic pharma- ceutical drugs. The SPP-V was successfully applied for the analysis of the degradation products of racemic citalopram whose enantiomers could be selectively identified by MS.

关键词： Mass spectrometry detection Chiral separation Basic drugs Beta-blockers Superficially porous particle Fully porous particle Fast separation Vancomycin

Screening primary racemic amines for enantioseparation by derivatized polysaccharide and cyclofructan columns

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Journal of Pharmaceutical Analysis 2016年第6期6卷 345-355页

作者： Yeeun Lim Zachary S.Breitbach Daniel w.armstrong Alain Berthod Department of Chemistry University of Texas at ArlingtonPlanetarium Place Institut des Sciences Analytiques CNRSUniversité de Lyon

It is a challenge to separate the enantiomers of native chiral amines prone to deleterious silanol interactions. Aset of 39 underivatized chiral primary amines was screened for enantiomeric separation. Seven recentlyintroduced commercial chiral columns were tested. They included six polysaccharide based chiral stationaryphases (CSP) with bonded derivatives, ChiralPak? IA, IB, IC, ID, IE and IF columns and a cyclofructanderivatized CSP, Larihc? CF6-P column. Both the normal phase (NP) mode with heptane/alcohol mobile phasesand the polar organic (PO) mode with acetonitrile/alcohol were evaluated. It was found that the cyclofructanbased CSP demonstrated the highest success rate in separating primary amines in the PO mode with only onechiral amine not resolved. It is shown that, when screening the columns, there is no standard optimal condition;an excellent mobile phase composition for one column may be poorly suited to another one. Althoughbutylamine was a good mobile phase additive for the polysaccharide columns in both PO and NP modes, it wasdetrimental to the enantio-recognition capability of the cyclofructan column. Triethylamine was the appropriatesilanol screening agent for this latter column.

关键词： Chiral primary amines Cyclofructan Bonded polysaccharide Enantiomeric separation

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溴甲烷熏蒸加利福尼亚核果上的桔小实蝇

植物检疫 1990年第3期4卷 173-175页

作者： John w.armstrong 于复坤

桔小实蝇 Dacus dorsalis Hendel(双翅目:实蝇科)是夏威夷和太平洋盆地其它地区的一个严重的农业害虫。许多国家已经对从感染地区进口的易感果蔬实行检疫限制,以阻止这种害虫的传人。桔小实蝇的寄主范围包括多达250种不同作物,而且这个... 详细信息

桔小实蝇 Dacus dorsalis Hendel(双翅目:实蝇科)是夏威夷和太平洋盆地其它地区的一个严重的农业害虫。许多国家已经对从感染地区进口的易感果蔬实行检疫限制,以阻止这种害虫的传人。桔小实蝇的寄主范围包括多达250种不同作物,而且这个昆虫对加利福尼亚州的数十亿美元的果蔬工业是一个严重的威胁。虽然北美本地没有桔小实蝇,但自从1960年以来几乎每年都偶然有桔小实蝇的传入。

关键词：桔小实蝇 dorsalis 农业害虫实蝇科地中海实蝇加利福尼亚州双翅目尼亚农业损失寄主范围

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生物技术生产天然调味品

生物工程进展 1989年第4期9卷 46-50页

作者： David w.armstrong 徐家立

目前,世界调味品市场销售额达20—30亿美元,而且还在增长。产生香和味的调味化合物其重量占世界所用食品添加剂的10—15％,但销售额却占到25％。市场向“天然”

关键词：生物技术天然调味品

Measurements of the ablation-front trajectory and low-mode nonuniformity in direct-drive implosions using x-ray self-emission shadowgraphy

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High Power Laser Science and Engineering 2015年第3期3卷 20-27页

作者： D.T.Michel A.K.Davis w.armstrong R.Bahr R.Epstein V.N.Goncharov M.Hohenberger I.V.Igumenshchev R.Jungquist D.D.Meyerhofer P.B.Radha T.C.Sangster C.Sorce D.H.Froula Laboratory for Laser Energetics University of Rochester

Self-emission x-ray shadowgraphy provides a method to measure the ablation-front trajectory and low-mode nonuniformity of a target imploded by directly illuminating a fusion capsule with laser beams. The technique uses time-resolved images of soft x-rays(>1 ke V) emitted from the coronal plasma of the target imaged onto an x-ray framing camera to determine the position of the ablation front. Methods used to accurately measure the ablation-front radius(δ R= ±1.15 μm), image-to-image timing(δ( t)= ±2.5 ps) and absolute timing(δt= ±10 ps) are *** averaging of the images provides an average radius measurement of δ( Rav)= ±0.15 μm and an error in velocity of δV / V= ±3%. This technique was applied on the Omega Laser Facility [Boehly et al., Opt. Commun. 133, 495(1997)] and the National Ignition Facility [Campbell and Hogan, Plasma Phys. Control. Fusion 41, B39(1999)].

关键词： low mode nonuiformity nuclear fusion self-emission shadowgraphy shell trajectory

应用环果糖和糖肽色谱柱亲水作用色谱法分离药用多肽

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应用环果糖和糖肽色谱柱亲水作用色谱法分离药用多肽

A novel method for clustering cellular data to improve classification

第二十届全国色谱学术报告会及仪器展览会

作者：舒杨陈旭伟王建华 Zachary S.Breitbacha Daniel w.armstrong 东北大学分析科学中心 Department of Chemistry and Biochemistry The University of Texas at Arlington

＜正＞本研究基于不同的功能参数,评价了三个环果糖色谱柱（Frulic N、Larihc P、Larihc RN）,两个糖肽色谱柱（Chirobiotic T、Chirobiotic V）和一个两性离子型亲水作用色谱柱（ZI-DPPS）的选择性,并将这六个亲水作用色谱的特性与先... 详细信息

＜正＞本研究基于不同的功能参数,评价了三个环果糖色谱柱（Frulic N、Larihc P、Larihc RN）,两个糖肽色谱柱（Chirobiotic T、Chirobiotic V）和一个两性离子型亲水作用色谱柱（ZI-DPPS）的选择性,并将这六个亲水作用色谱的特性与先前评估过的33个色谱柱进行比较（见图1）。硅胶键合丙基氨基甲酸酯衍生的环六果糖色谱柱Larihc P与硅胶键合天然环果糖色谱柱Frulic N相比,亲水性降低。首先由于未被取代的剩余硅胶的去质子化作用,Frulic N和Larihc P都表现出阳离子交换的

关键词：亲水作用色谱选择性环果糖固定相糖肽固定相药用多肽

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Neural Regeneration Research 2025年第9期20卷 2697-2705页

作者： Diek w.wheeler Giorgio A.Ascoli Center for Neural Informatics Structures&PlasticityKrasnow Institute for Advanced Study Bioengineering Department Volgenau School of Engineering George Mason University FairfaxVAUSA

Many fields,such as neuroscience,are experiencing the vast prolife ration of cellular data,underscoring the need fo r organizing and interpreting large datasets.A popular approach partitions data into manageable subsets via hierarchical clustering,but objective methods to determine the appropriate classification granularity are *** recently introduced a technique to systematically identify when to stop subdividing clusters based on the fundamental principle that cells must differ more between than within *** we present the corresponding protocol to classify cellular datasets by combining datadriven unsupervised hierarchical clustering with statistical *** general-purpose functions are applicable to any cellular dataset that can be organized as two-dimensional matrices of numerical values,including molecula r,physiological,and anatomical *** demonstrate the protocol using cellular data from the Janelia MouseLight project to chara cterize morphological aspects of neurons.

关键词： cellular data clustering dendrogram data classification Levene's one-tailed statistical test unsupervised hierarchical clustering

Genistein:a possible solution for the treatment of Alzheimer’s disease

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Neural Regeneration Research 2025年第10期20卷 2903-2905页

作者： Karolina Pierzynowska Bartosz Karaszewski Grzegorz węgrzyn Department of Molecular Biology University of GdanskGdanskPoland Gdansk Polandand Department of Adult NeurologyFaculty of MedicineMedical University of GdanskGdanskPoland

Neurodegenerative diseases are defined as disorders resulting from the slow and progressive loss of function and eventual death of neural cells that result from the primary pathology of nervous *** can lead to severe nervous system dysfunction,eventually affecting multiple organs and *** hundred neurodegenerative diseases have been described,and owing to their prevalence,severity.

关键词： organs Alzheimer death

Glia-to-neuron reprogramming to the rescue?

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Neural Regeneration Research 2025年第5期20卷 1395-1396页

作者： Jack w.Hickmott Cindi M.Morshead Department of Surgery University of TorontoTorontoONCanada Donnelly Centre for Cellular and Biomolecular Research TorontoONCanada Institute of Biomedical Engineering University of TorontoTorontoONCanada The KITE Research Institute Toronto Rehabilitation InstituteUniversity Health NetworkTorontoONCanada

Over the last two decades,the dogma that cell fate is immutable has been increasingly challenged,with important implications for regenerative *** brea kth rough discovery that induced pluripotent stem cells could be generated from adult mouse fibroblasts is powerful proof that cell fate can be *** exciting extension of the discovery of cell fate impermanence is the direct cellular reprogram ming hypothesis-that terminally differentiated cells can be reprogrammed into other adult cell fates without first passing through a stem cell state.

关键词： programming passing proof