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Giving Food a Fiber Boost: Adding High Beta-Glucan Ingredient from Barley to Everyday Foods

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Immobilization of Penicillin G Acylase on Calcined Layered Double Hydroxides

Food and Nutrition Sciences（食品与营养科学） 2024年第4期 277页

作者： Gongshe Hu Sherry Ellberg Kathy Satterfield Chris evans

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Chemical Research in Chinese Universities 2003年第3期19卷 324-329页

作者： evans D.G. Key Laboratory of Science & Technology of Controllable Chemical Reactions

A hydrotalcite-like Mg 2+ /Al 3+ layered double hydroxide(LDH) material was prepared by means of a modified coprecipitation method involving a rapid mixing step followed by a separate aging process. LDH calcined at 500 ℃, denoted as CLDH, was characterized by XRD, IR and BET surface area measurements. CLDH has a poor crystalline MgO-like structure with a high surface area and porosity. CLDH was used as a support for the immobilization of penicillin G acylase(PGA). The effect of varying the immobilization conditions, such as pH, contact time and the ratio of enzyme to support, on the activity of the immobilized enzyme in the hydrolysis of penicillin G has been studied. It was found that the activity of the immobilized enzyme decreased slightly with decreasing pH and reached a maximum after a contact time of 24 h. The activity of the immobilized enzyme increased with increasing the ratio of enzyme to support. It was found that the adsorption of PGA inhibited the expected reaction of CLDH with an aqueous medium to regenerate a LDH phase. Its original activity(36%) after 15 cycles of reuse of the immobilized enzyme was retained, but no further loss in the activity was observed.

关键词： Immobilized enzyme Penicillin G acylase Layered double hydroxide Calcination

Study on the supramolecular structure of sorbic acid inter-calated Zn-Al layered double hydroxides and its thermal decomposition

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Chinese Science Bulletin 2005年第22期50卷 2575-2581页

作者： David G. evans Ministry of Education Key Laboratory of Science and Technology of Controllable Chemical Reactions Beijing University of Chemical Tech- nology Beijing 100029 China

A novel organic-inorganic composite, sorbic acid intercalated zinc aluminum layered double hydroxides (SA-ZnAl-LDHs) has been successfully assembled by a sim- ple direct coprecipitation method. A holistic approach in- cluding normal XRD, FT-IR, and UV-Vis measurements and simultaneous TG/DTA/MS and in situ HT-XRD techniques was employed to explore the supramolecular intercalation structure and the thermal decomposition properties of as-synthesized SA-ZnAl-LDHs material.

关键词：氢氧化铝超分子结构热量分解插入结构 HT-XRD 有机化合物

Modeling endodermal organ development and diseases using human pluripotent stem cell-derived organoids

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Journal of Molecular Cell Biology 2020年第8期12卷 580-592页

作者： Fong Cheng Pan Todd evans Shuibing Chen Department of Surgery Weill Cornell Medical CollegeNew YorkNY 10065USA

Recent advances in development of protocols for directed differentiation from human pluripotent stem cells(hPSCs)to defined lineages,in combination with 3D organoid technology,have facilitated the generation of various endoderm-derived organoids for in vitro modeling of human gastrointestinal development and associated *** this review,we discuss current state-ofthe-art strategies for generating hPSC-derived endodermal organoids including stomach,liver,pancreatic,small intestine,and colonic *** also review the advantages of using this system to model various human diseases and evaluate the shortcomings of this ***,we emphasize how other technologies,such as genome editing and bioengineering,can be incorporated into the 3D hPSC-organoid models to generate even more robust and powerful platforms for understanding human organ development and disease modeling.

关键词： human pluripotent stem cells endoderm gastrointestinal development disease modeling

Synthesis of layered LiMnO_2 by in situ oxidation-intercalation and a study of the reaction mechanism and electrochemical performance

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Chinese Science Bulletin 2005年第3期50卷 213-216页

作者： D.G.evans Key Laboratory of Science and Technology of Controllable Chemical Reactions Ministry of EducationBeijing University of Chemical Tech- nologyBeijing 100029China

Using Mn(OH)2 as precursor, LiOH as lithiat- ing agent and (NH4)2S2O8 as oxidant, layered o-LiMnO2 was obtained by a novel method——in situ oxidation-intercalation under mild conditions (80℃). The product was characterized by XRD, ICP, TEM and Li-NMR. The results reveal that 7 orthorhombic LiMnO2 with high purity and good crystallin- ity can be obtained by this method. During electrochemical tests, a LiMnO2/Li cell shows an initial reversible capacity of 208 mAh·g?1 and a reversible capacity of 180 mAh·g?1 after 30 cycles at room temperature.

关键词： LiMnO2 氧化反应电化学特性锂离子电池分析方法

Microbial Degradation of Organic Contaminants in Streambed/Floodplain Sediments in Passaic River—New Jersey Area

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Does the autonomic nervous system contribute to the initiation and progression of prostate cancer？

American Journal of Analytical Chemistry（美国分析化学） 2024年第4期 139页

作者： Taheim evans English Meghann Trombetta Alyssa Beres Yusuf Yildiz

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Asian Journal of Andrology 2013年第6期15卷 715-716页

作者： Sabatino Ventura Bronwyn a.evans Drug Discovery Biology Monash Institute of PharmaceuticalSciences Monash University Parkville Vic. 3052 Australia

In the July 12 issue of Science maga-zine, researchers from the AlbertEinstein College of Medicine, the Mount Sinai School of Medicine, the Durham VA Medical Centre and Duke University published an elegant study demonstrating that the sym-pathetic nervous system, acting through β2 and β3-adrenoceptors in the prostate, plays an important role in the initiation of prostate can-cer, while the parasympathetic nervous system plays a role in the dissemination of tumour metastases via M1 muscarirdc receptors. These findings are significant because they indicate that receptors associated with the autonomic nervous system may be viable tar-gets for prostate cancer therapy.

关键词： GROWTH SWITCH

Misalignment Between Skills Discovered, Disseminated, and Deployed in the Knowledge Economy

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Journal of Social Computing 2022年第3期3卷 191-205页

作者： Bhargav Srinivasa Desikan James evans the Department of Computer and Communication Sciences École Polytechnique Fédérale de Lausanne(EPFL)Lausanne 1015Switzerland the Knowledge Lab the Department of SociologyUniversity of ChicagoChicagoIL 60615USAand also with the Santa Fe InstituteSanta FeNM 87501USA

The knowledge economy is a complex and dynamical system,where knowledge and skills are discovered through research,diffused via education,and deployed by *** aligning the supply of new knowledge with the demand for practical skills through education is critical for developing national innovation systems that maximize human *** this paper,we evaluate the complex alignment of skills across the knowledge economy by creating an integrated semantic model that neurally encodes invented,instructed,and instituted skills across three major datasets:research abstracts from the Web of Science,teaching syllabi from the Open Syllabus Project,and job advertisements from Burning *** the high dimensional knowledge and skills space inscribed by these data,we draw critical insight about systemic misalignment between the diversity of skills supplied and demanded in the knowledge *** with insights from economic geography,demand for skills from industry exhibits high entropy(diversity)at local,regional,and national levels,demonstrating dense complementarities between them at all levels of the *** with the economics and sociology of innovation,we find low entropy in the invention of new knowledge and skills through research,as specialist researchers cluster within *** provide new evidence,however,for the low entropy of skills taught at local,regional,and national levels,illustrating a massive mismatch between diversity in skills supplied versus *** misalignment is sustained by the spatial and institutional mismatch in the organization of education by researchers at the site of skill invention over *** findings suggestively trace the societal costs of tethering education to researchers with narrow knowledge rather than students with broad skill needs.

关键词： computational content analysis knowledge economy sociology of knowledge natural language processing data science and society

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细胞无性系变异及其在植物育种体上的应用

生物技术通报 1989年第5期5卷 1-5页

作者： David a.evans 陈志贤王娇娟

科学家们对生长在培养基上的植物细胞产生广泛的遗传变异的发现已有若干年了。早期的一些报道记述了细胞的多倍性、非整倍性、细胞分裂后期桥,以及片段和染色体的稳定性。过去几年的研究观察大体上已得出一个结论:长期生长在培养基上的... 详细信息

科学家们对生长在培养基上的植物细胞产生广泛的遗传变异的发现已有若干年了。早期的一些报道记述了细胞的多倍性、非整倍性、细胞分裂后期桥,以及片段和染色体的稳定性。过去几年的研究观察大体上已得出一个结论:长期生长在培养基上的植株细胞遗传是不稳定的,通常会失去再生植株的能力。

关键词：无性系植物育种非整倍性遗传变异多倍性分裂后期有丝分裂交换染色体结构突变体减数分裂