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Peat record reflecting Holo-cene climatic change in the Zoige Plateau and AMS radiocarbon dating

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Chinese Science Bulletin 2002年第1期47卷 66-70页

作者： ZHOU Weijian LU Xuefeng WU Zhengkun DENG Lin A.J.T.Jull D.donahue W.Beck State Key Lab of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710054China NNSF-AMS Facility University of Arizona

Through the use of reliable AMS dating of high resolution (15-30 years) peat and the establishment of monsoon climate proxies sequence, we have been able to recognize several cold, dry events in the Tibetan Plateau during the Holocene. The more obvious ones occurred around 12800, 11300, 10200, 9580, 8900, 6400, 4400, 3700, 2800 and 1500 cal. aBP. These events correlate well with both ice rafting events recorded in high latitude North Atlantic Ocean sediment cores and cooling events in the low latitude SST. Spectral analysis indicates high frequency climate variation on centennial-millennial time scale during the Holocene. This further reflects Holocene climate instability and the existence of centennial-millenium scale rhythm in mid latitude areas as well.

关键词： Zoige Holocene high-resolution record peat AMS dating climate instability.

南海全新世珊瑚礁AMS^(14)C,^(230)Th/^(234)U和ESR年龄的对比研究

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海洋科学 1993年第2期17卷 63-65页

作者：业渝光 D.J.donahue 地质矿产部海洋地质研究所青岛266071 美国亚利桑那大学

用^(14)C(AMS和稀释技术),铀系和ESR方法对南海珊瑚礁进行了测年对比研究,表明这些珊瑚礁形成于全新世早、中期。此外,对测年方法的一些有关问题也进行了讨论。

关键词：珊瑚礁 AMS^14C ESR 铀系年龄

Fabrication and Characterization of Chitosan Based Injectable Thermosensitive Hydrogels Containing Silica/Calcium Phosphate Nanocomposite Particles

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Journal of Biomaterials and Nanobiotechnology 2021年第3期12卷 34-48页

作者： Seyed Mohsen Latifi Christina Tang Henry J. donahue Bone Engineering Science and Technology (BEST) Lab Department of Biomedical Engineering Virginia Commonwealth University Richmond VA USA Department of Chemical and Life Sciences Engineering Virginia Commonwealth University Richmond VA USA

In this study, the effect of silica/calcium phosphate (SiCaP) nanocomposite particles on the properties of a novel chitosan-based thermosensitive hydrogel system was examined. SiCaP nanocomposite powder was fabricated using a sol-gel method and then used to fabricate nanocomposite hydrogels (Ch- β/7.5SiCaP and Ch-β/15SiCaP) including chitosan and β-glycerophosphate (Ch-β) as a matrix. Results revealed that compared to the Ch-β hydrogel without SiCaP, the presence of SiCaP particles in nanocomposite hydrogels maintained pH stability during the sol-gel transition, accelerated the gelation and improved the stiffness of nanocomposite hydrogels. Gelation time at 37℃ was reduced approximately 75% and stiffness was increased approximately 115%. Both of these changes are attributed to chemical and physical interactions of the SiCaP bioactive particles with chitosan. Furthermore, compared to the Ch-β hydrogel, the presence of SiCaP in the Ch-β/7.5SiCaP nanocomposite hydrogel did not affect biocompatibility negatively, but improved osteoblastic cell differentiation. Our studies suggest that these nanocomposite hydrogels may offer an innovative approach to bone regeneration strategies.

关键词： Thermosensitivity Composite Hydrogel Bioactive Particles Rheology Biocompatibility

Polydopamine Coating on Titanium Affects Osteoblastic Differentiation to a Greater Degree than Does Surface Roughness

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Advances in Materials Physics and Chemistry 2020年第12期10卷 339-349页

作者： Seyed Mohsen Latifi Ravi Shankar Henry J. donahue Bone Engineering Science and Technology (BEST) Lab Virginia Commonwealth University Richmond USA

Biointerface design can greatly influence cell behavior. Therefore, in this study we examined the effects of three surface characteristics, roughness, chemistry, and wettability, on osteoblastic cell differentiation. We examined osteoblastic differentiation on titanium (Ti) samples with four levels of roughness (average roughness: 148.6 ± 23.1, 42 ± 6.2, 14.3 ± 5.5, 7.2 ± 1.6 nm) with or without a nanolayer coating of polydopamine (PDA). In vitro osteogenic differentiation was evaluated by quantifying alkaline phosphatase (AP) activity of human fetal preosteoblastic (hFOB 1.19) cells. The change in surface chemistry of Ti samples as a result of PDA coating was assessed by XPS analysis and water contact angle measurement. Results demonstrated that PDA treated samples were more hydrophilic, compared to untreated samples, and this was substrate roughness independent. Moreover, with the exception of the substrate with an oriented texture of surface nanotopography (RTi-4), the presence of a PDA nanolayer increased AP activity independent of substrate roughness. Our results suggest that surface chemistry and wettability, induced by a PDA nanolayer coating, had a greater effect on osteoblastic differentiation than did surface roughness.

关键词： Surface Chemistry Roughness Polydopamine Wettability Osteoblastic Differentiation

The Butterfly on the Redwood

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中学生阅读（高中版） 2004年第6期 22-页

作者： Paul donahue 保罗·唐纳休刘杰

导读:红杉树是一种跟恐龙同时代的植物。在半个世纪之前,北美有数十万公顷的原始红杉树。然而,由于木材加工业的步步紧逼,在今天红杉树已成为濒危植物。24岁的朱丽叶·希尔是一个漂亮的加利福尼亚女郎。她有一颗水晶般的爱心,芙丽而又... 详细信息

导读:红杉树是一种跟恐龙同时代的植物。在半个世纪之前,北美有数十万公顷的原始红杉树。然而,由于木材加工业的步步紧逼,在今天红杉树已成为濒危植物。24岁的朱丽叶·希尔是一个漂亮的加利福尼亚女郎。她有一颗水晶般的爱心,芙丽而又热爱大自然,人们给她起了个“蝴蝶”的绰号。为了保护世界上罕见的、珍贵的名叫“卢娜”的红杉树免遭砍伐,朱丽叶·希尔不畏艰辛,在一棵红杉树上安营扎寨,度过了738个日日夜夜。最终,她凭借自己的勇气和努力赢得了胜利,同时她的智慧与善谈也使她成了一位出色的环保活动家。(虹雨)

关键词：朱丽叶 The Butterfly on the Redwood

Mediator complex subunit 12 is a gatekeeper of SARS-CoV-2 infection in breast cancer cells

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Genes & Diseases 2022年第1期9卷 5-8页

作者： Shengjie Zhang Fabao Liu Peter Halfmann Ryan TBehrens Peng Liu Sean JMcilwain Irene MOng Kristine donahue Yidan Wang Yoshihiro Kawaoka Nathan Sherer Wei Xua McArdle Laboratory for Cancer Research University of Wisconsin-MadisonMadisonWI 53706USA Department of Pathobiological Sciences School of Veterinary MedicineUniversity of WisconsinMadisonWI 53706USA Department of Biostatistics and Medical Informatics School of Medicine and Public HealthUniversity of WisconsinMadisonWI 53706USA Department of Biostatistics and Medical Informatics Carbone Cancer CenterUniversity of WisconsinMadisonWI 53706USA Department of Obstetrics and Gynecology School of Medicine and Public HealthUniversity of WisconsinMadisonWI 53706USA Cancer Hospital of the University of Chinese Academy of Sciences(Zhejiang Cancer Hospital) Institute of Basic Medicine and Cancer(IBMC)Chinese Academy of SciencesHangzhouZhejiang 310022China

Cancer patients are at increased risk for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection and *** other viruses in the SARS family,SARS-CoV-2 employs two host proteins,angiotensin-converting enzyme 2(ACE2)and transmembrane serine protease 2(TMPRSS2),for viral entry.1 Recent studies showed that many of the host proteins identified as potential targets for developing COVID therapies are dysregulated in cancer,2 prompting us to investigate whether human cancer cells are susceptible to SARS-CoV-2 infection,and whether chemotherapy could modulate a cancer patient's risk for infection.

关键词： infection ACE2 cancer

Plasma-Based Graphene Functionalization in Glow Discharge

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Graphene 2015年第1期4卷 1-6页

作者： X. Fang J. donahue A. Shashurin M. Keidar Department of Mechanical & Aerospace Engineering The George Washington University Washington DC USA

Glow discharge was utilized to add oxygen functional groups to the graphene platelets sample produced in chemical exfoliation synthesis. It was concluded based on Raman spectra that the graphene sample treated with the glow discharge preserves specific graphene features while no transformation to amorphous carbon is happening. SEM and EDS results indicated the increases of oxygen content in the graphene sample after the exposure to the glow discharge. Raman spectra also support the fact that the graphene platelets have been decorated with oxygen as the result of the glow discharge treatment.

关键词： Graphene Functionalization Plasma-Based

MEASURING THE LUMINANCE OF A RETROREFLECTIVE SIGN

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MEASURING THE LUMINANCE OF A RETROREFLECTIVE SIGN

26th Session of the CIE

作者： Miller,Cameron Heimer,Todd donahue,Tim Schwartz,Matthew Kuniega,David National Institute of Standards and Technology USA Gamma Scientific Corporation USA The 3M Company USA Pennsylvania Department of Transportation USA

The area of retroreflective signage for traffic control is moving from fixed retroreflective requirements to a traffic scenario/performance based *** Technical Report 54.2, “Retroreflection:Definition and Measurement”,published in 2001,offers several methods for measuring the coefficient of retroreflected *** this experiment,two CIE 54.2 methods, The Ratio Method and The Direct Luminance Method,along with a new method,Total Luminous Flux Method,are compared in the laboratory and through uncertainty *** results show the Total Luminous Flux method has the potential for the lowest measurement uncertainty and implementation of the Direct Luminance method is not trivial showing errors as large as 20 % are easily possible.

关键词： luminance retroreflection uncertainty

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埃塞俄比亚成为全球时尚供应链一环的背后

商业周刊（中文版） 2018年第5期 68-73页

作者： Bill donahue

在永欣集团（IndochineInternational）崭新的埃塞俄比亚工厂，这家中国服装制造商的副总裁拉加夫·帕塔（RaghavPattar）站在一间阳光明媚的办公室里，看上去神采奕奕。

关键词：埃塞俄比亚供应链时尚中国服装办公室副总裁制造商集团