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Protein Precipitation to Remove Carbohydrates that Interfere in Protein-Bound Tryptophan Quantification in Soybean Seeds

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Journal of Analysis and Testing 2020年第3期4卷 238-247页

作者： Zhentian Lei Santosh Kumar Saurav J.Sarma Ritesh Kumar Barbara W.sumner Minviluz G.Stacey lloyd W.sumner University of Missouri Metabolomics Center ColumbiaMO 65211USA Division of Biochemistry University of MissouriColumbiaMO 65211USA Division of Plant Sciences University of MissouriColumbiaMO 65211USA

Tryptophan is one of the nine essential amino acids in humans that can only be obtained through diets and *** is a precursor to many biological processes,such as serotonin,melatonin,kynurenin,and niacin(nicotinamide)vitamin *** content of tryptophan in foods,such as soybean is an important indicator of nutritional ***,accurate quantification of tryptophan in soybean is crucial to soybean nutritional *** of soybean protein-bound amino acids first involves acid hydrolysis of total protein to liberate amino ***,tryptophan quantification following acid hydrolysis is difficult or impossible due to its reactions with soybean ***,removal of carbohydrates from soy proteins prior to acid hydrolysis is *** this study,we compared four common protein precipitation methods(i.e.,methanol,acetonitrile,acetone,and trichloroacetic acid(TCA)protein precipitation methods)to determine the best method to separate soy proteins from carbohydrates,and concluded that acetone provided the highest recovery of soy *** content in the precipitated proteins was determined after acid hydrolysis of the proteins using liquid chromatography-tandem mass spectrometry multiple reaction monitoring(LC-MS/MS-MRM).No significant difference in the tryptophan content was found among proteins precipitated with methanol,acetonitrile,and TCA,suggesting that these precipitated proteins have similar compositions.A slightly lower,but statistically significant tryptophan content was found in the acetonitrile-precipitated proteins,suggesting that these proteins contain slightly higher glycosylated proteins.

关键词： Tryptophan Acid hydrolysis LC-MS/MS MRM Soybean seeds Protein precipitation

Characterization of the Formation of Branched Short-Chain Fatty Acid：CoAs for Bitter Acid Biosynthesis in Hop Glandular Trichomes

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Molecular Plant 2013年第4期6卷 1301-1317页

作者： Haiyang Xu Fengxia Zhang Baoxiu Liu David V. Huhman lloyd W. sumner Richard A. Dixon Guodong Wang State Key Laboratory of Plant Genomics and National Center for Plant Gene Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100039 China The Samuel Roberts Noble Foundation Plant Biology 2510 Sam Noble Parkway Ardmore OK 73401 USA Current address: Department of Biological Sciences University of North Texas Denton Texas 76203 USA

Bitter acids, known for their use as beer flavoring and for their diverse biological activities, are predominantly formed in hop （Humulus lupulus） glandular trichomes. Branched short-chain acyI-CoAs （e.g. isobutyryI-CoA, isovaleryl- CoA and 2-methylbutyryI-CoA）, derived from the degradation of branched-chain amino acids （BCAAs）, are essential building blocks for the biosynthesis of bitter acids in hops. However, little is known regarding what components are needed to produce and maintain the pool of branched short-chain acyI-CoAs in hop trichomes. Here, we present several lines of evidence that both CoA ligases and thioesterases are likely involved in bitter acid biosynthesis. Recombinant HICCL2 （carboxyl CoA ligase） protein had high specific activity for isovaleric acid as a substrate （Kcat/Km = 4100 s-~ M-l）, whereas recombinant HICCL4 specifically utilized isobutyric acid （Kcat/Km = 1800 s-1 M-1） and 2-methylbutyric acid （Kcat/ Km = 6900 s-1 M-~） as substrates. Both HICCLs, like hop valerophenone synthase （HIVPS）, were expressed strongly in glandular trichomes and localized to the cytoplasm. Co-expression of HICCL2 and HICCL4 with HIVPS in yeast led to significant production of acylphloroglucinols （the direct precursors for bitter acid biosynthesis）, which further confirmed the biochemical function of these two HICCLs in vivo. Functional identification of a thioesterase that catalyzed the reverse reaction of CCLs in mitochondria, together with the comprehensive analysis of genes involved BCAA catabolism, supported the idea that cytosolic CoA ligases are required for linking BCAA degradation and bitter acid biosynthesis in glandular trichomes. The evolution and other possible physiological roles of branched short-chain fatty acid：CoA ligases in planta are also discussed.

关键词： CoA ligase glandular trichomes bitter acid thioesterase evolution Humulus lupulus

Resource discovery in distributed digital libraries through visual knowledge navigation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2005年第11期6卷 1306-1311页

作者： AHMAD Faisal sumner Tamara Department of Computer Science University of Colorado Colorado 80309-0430 USADepartment of Computer Science University of Colorado Colorado 80309-0430 USA

In order to support users to search and browse for various resources, digital libraries are composed of discovery systems which provide user interface and information retrieve system. Recent researches in Information Retrieval have investi- gated different techniques through improving precision and recall to enhance the effectiveness of discovery system in digital libraries. In this paper, we present our work to enhance discovery system effectiveness with a different approach, through resource discovery based on visual knowledge navigation. In our Strand Map Services project under National Science Digital Library, we introduce the visual resource discovery system called conceptual browsing interfaces, to help educators and learners to locate, comprehend and use educational resources in digital libraries. The paper begins with a short introduction of the Strand Map Services. Then we illustrate the service architecture, the design and implementation of its major components. We will focus our discussion of how the visualization system of the Strand Map Services supports the visual knowledge navigation for distributed digital libraries. This includes the knowledge acquisition of the conceptual browsing interfaces, different knowledge representa- tions in the system perspective and user interface perspective, visualization system modules, algorithm and Web services inte- gration to use visual knowledge navigation to enhance resource discovery in digital libraries.

关键词：数字图书馆发现系统视频系统网络服务信息修复

INVESTIGATION ON LYMPHOCYTE SUBPOPULATIONS IN THE INTESTINAL LAMINA PROPRI IN INFLAMMATORY BOWEL DISEASES

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中华医学杂志(英文版) 1992年第1期105卷 18-24页

作者：袁世珍王宁生 sumner C.Kraft Department of Medicine University of Chicago Illinois USA

Intestinal lamina proprial lymphocytes were enu-merated in 13 patients with Crohn's disease(CD),7with ulcerative colitis(UC)and 9 control subjects withgrossly norfmal *** percentages and absolutenumbers of B cells and complement receptor-bearinglymphocytes in the patients with UC did not differsignificantly from those of the control group;but inCD,the percentages of these cells were significantlydecreased despite that the absolute numbers were *** percentages and abolute numbers of T cellsidentified by E rosettes(regular and stable)were nor-mal in both CD and *** both diseases,significantlyincreased percentages but normal absolute numbers ofmature T cells were identified by monoclonal antibodystaining with the CD3 *** was an increasedproportion of suppressor/cytotoxic T cells and aconcomitant significant decrease of the helper tosuppressor T-cell ratio (using either percentages orabsolute numbers of cells)in tissues from patients withCD,but not with UC as compared with the *** results suggest that the imbalance ofT-cell subpopulations in the intestinal lamina propriamay play a role in the pathogenesis of CD.

关键词： SUB-POPULATIONS CROHNS-DISEASE CELLS

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微网中储能系统的能量管控方法

中国电机工程学报 2016年第10期36卷 2665-2673页

作者：贾科陈奕汝毕天姝 Mark sumner 新能源电力系统国家重点实验室(华北电力大学) 北京市昌平区102206 诺丁汉大学

微网利用光伏、风机等可再生能源发电(renewable energy source of electricity,RES-E)并与能量存储系统配合向本地负荷供电,可以减小能量传输损耗以及大电网扰动的影响。然而,微网中的可再生能源分布式电源出力与负荷逆向分布,如何利... 详细信息

微网利用光伏、风机等可再生能源发电(renewable energy source of electricity,RES-E)并与能量存储系统配合向本地负荷供电,可以减小能量传输损耗以及大电网扰动的影响。然而,微网中的可再生能源分布式电源出力与负荷逆向分布,如何利用储能元件实现能源就地高效利用、避免大量过剩功率入网是当前微网发展重点之一。针对这一问题,该文提出一种可变阈值的自动适应控制方法,采用自适应智能技术控制储能元件的即时充放电功率,提高电能分配效率,实现对于负荷的"削峰填谷"。文中利用现场测得的RES数据对提出的方法进行验证,结果表明与传统利用固定阈值和需要精确预测的方法相比提出的方法在不需要RES和负荷预测数据的情况下,可以更有效减小负荷峰值,得到更加平滑的负荷曲线,同时最大程度地利用本地RES能源。

关键词：微网可再生能源自适应智能技术电池储能能量管理可变阈值

A case study of multi-seam coal mine entry stability analysis with strength reduction method

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矿业科学技术学报：英文版 2016年第2期26卷 193-198页

作者： Tulu Ihsan Berk Esterhuizen Gabriel S. Klemetti Ted Murphy Michael M. sumner James Sloan Michael Ground Control Branch NIOSH Office of Mine Safety and Health Research Pittsburgh PA 15216 USA Lone Mountain Processing Inc. St. Charles VA 24282 USA

In this paper,the advantage of using numerical models with the strength reduction method(SRM) to evaluate entry stability in complex multiple-seam conditions is demonstrated.A coal mine under variable topography from the Central Appalachian region is used as a case *** this mine,unexpected roof conditions were encountered during development below previously mined *** mapping and observation of ground conditions were used to quantify the success of entry support systems in three room-and-pillar *** model analyses were initially conducted to estimate the stresses induced by the multiple-seam mining at the locations of the affected *** SRM was used to quantify the stability factor of the supported roof of the entries at selected *** SRM-calculated stability factors were compared with observations made during the site visits,and the results demonstrate that the SRM adequately identifies the unexpected roof conditions in this complex *** is concluded that the SRM can be used to effectively evaluate the likely success of roof supports and the stability condition of entries in coal mines.

关键词：稳定性分析强度折减煤层巷道多煤层开采实例数值模型煤矿井下应力影响

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格雷斯水泥添加剂应用技术

格雷斯水泥添加剂应用技术

首届水泥助磨剂应用技术研讨会

作者： Mike sumner 格雷斯建材产品公司

本文主要想介绍一下格雷斯水泥添加剂的应用技术。拟从以下三个部分来阐述:水泥添加剂的作用原理;水泥添加剂的应用价值;水泥添加剂的实例研究。 1 水泥添加剂的作用机理在水泥粉磨过程中,添加一定量的水泥添加剂,能有效地增加水泥颗粒...

本文主要想介绍一下格雷斯水泥添加剂的应用技术。拟从以下三个部分来阐述:水泥添加剂的作用原理;水泥添加剂的应用价值;水泥添加剂的实例研究。 1 水泥添加剂的作用机理在水泥粉磨过程中,添加一定量的水泥添加剂,能有效地增加水泥颗粒表面,减少水泥颗粒之间的聚集现象,减少水泥磨内的糊球现象;同时提高磨机系统的选粉效率,减少磨内的物料量,缩短水泥在磨内的停留时间(MRT)和降低磨机填充率。

关键词：

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Feeding the Busy

大学英语 1993年第3期 21-22页

作者： Margaret sumner 谭凯莹

There are times when one just seems to be too busy to eat. Mothers looking after stoat| children; business people trying to prepare for an important meeting; actors during the last few days of rehearsal; students before their examinations; brides getting ready for the wedding; people in all sorts of circumstances find it difficult to

关键词： Feeding the Busy

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美国肉鸡产业历程及未来发展方向

美国肉鸡产业历程及未来发展方向