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药学进展 1961年第Z1期 7-8页

作者： Shih Chu jack e.har Henry G.Man 赵连昌

作者鉴于将氮芥类化合物中的双(β—氯乙基)胺基和抗疟药、氨基酸、甾醇类化合物等分子相联,可以增强其制癌效用;同时又根据“交链结合”的假說,于是合成了黄嘌吟、次黃嘌吟、腺嘌吟的8—双(β—氯乙基)胺基等衍生物。

关键词：氮芥类抗疟药氯乙基交链闭水气月于明

Application of the Shrinking Particle Model for the evaluation of Molecular Recyclability of PeT versus Semi-Aromatic Polyesters

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Open Journal of Physical Chemistry 2024年第2期14卷 21-35页

作者： jack van Schijndel Sanne de Krom Dennis Molendijk Koen van Beurden Amarante Böttger Research Group Biopolymers/Green Chemistry Centre of Expertise Safe & Resilient Society Avans University of Applied Science Breda Netherlands New Materials and Their Applications Centre of Expertise Safe & Resilient Society Avans University of Applied Science Breda Netherlands Department of Materials Science and engineering Delft University of Technology Delft Netherlands

The molecular recyclability of poly (ethylene terephthalate) (PeT) and three semi-aromatic polyesters poly (phloretic acid) (poly-H), poly (dihydroferulic acid) (poly-G), and poly (dihydrosinapinic acid) (poly-S) is evaluated in this study. PeT is an extensively used aromatic polyester, and poly-H, poly-G, and poly-S can be considered semi-aromatic poly (lactic acid) modifications. All these polyesters have been depolymerized at neutral pH and by acid- and base-catalyzed hydrolysis at two temperatures, i.e., 50˚C and 80˚C. Base-catalyzed depolymerization of virgin PeT leads to an isolated yield of 38% after 48 hours of reaction at 80˚C. Contrary to these results for PeT, almost all the monomers of the semi-aromatic polyesters poly-H, poly-G, and poly-S are recovered with isolated yields larger than 90% at the same temperature after 15 minutes in a facile manner. A shrinking particle model used to determine the global kinetics of the base-catalyzed depolymerization showed that the rate rises with increasing temperature. Using the shrinking particle model, the intrinsic reaction rate constants were determined. It has been demonstrated that the rate coefficients of the depolymerization of the semi-aromatic polyesters poly-H, poly-G, and poly-S are between 2 and 3 orders of magnitude higher than those for PeT.

关键词： Depolymerization Molecular Recycling Poly-H Poly-G Poly-S PeT Circular Polymers

Disturbance cue communication is shaped by emitter diet and receiver background risk in Trinidadian guppies

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Current Zoology 2022年第4期68卷 433-440页

作者： jack A Goldman Adam L Crane Laurence e A Feyten emily Collins Grant e Brown Department of Biology Concordia University7141 Sherbrooke Street WestMontrealQCCanada H4B 1R6

In animal communication systems,individuals that detect a cue(i.e.,“receivers”)are often influenced by characteristics of the cue *** instance,in many species,receivers avoid chemical cues that are released by emitters experiencing *** chemical“disturbance cues”appear to benefit receivers by warning them about nearby danger,such as a predator’s *** the active ingredients in disturbance cues have been largely unexplored,by-products of metabolized protein are thought to play a role for some *** so,the content(quality)and volume(quantity)of the emitter’s diet should affect their disturbance cues,thus altering how receivers perceive the cues and *** Poecilia reticulata are a species known to discriminate among disturbance cues from different types of donors,but dietary variation has yet to be *** this study,we found evidence that diet quality and quantity can affect disturbance cues released by guppy emitters(i.e.,experimental“donors”).Receivers discriminated between donor cue treatments,responding more strongly to cues from donors fed a protein-rich bloodworm diet(experiment 1),as well as an overall larger diet(experiment 2).We also found that receivers exposed to higher background risk were more sensitive to disturbance cue variation,with the strongest avoidance responses displayed by high-risk receivers toward disturbance cues from donors fed the high-quality ***,diet,and perhaps protein specifically,affects either the concentration or composition of disturbance cues released by *** variation may be important in information signaling in social species like the guppy.

关键词： alarm cues chemical cues diet quality diet quantity protein

Sender and receiver experience alters the response of fish to disturbance cues

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Current Zoology 2020年第3期66卷 255-261页

作者： jack A.GOLDMAN Laurence e.A.FeYTeN Indar W.RAMNARINe Grant e.BROWN Department of Biology Concordia University7141 Sherbrooke St.WestMontrealQCH4B 1R6Canada Department of Lifte Sciences University of the West IndiesSt.AugustineTrinidad and Tobago

Predation is a pervasive selection pressure,shaping morphological,physiological,and behavioral phenotypes of prey *** studies have begun to examine how the effects of individual experience with predation risk shapes the use of publicly available risk assessment ***,we investigated the effects of prior predation risk experience on disturbance cue production and use by Trinidadian guppies Poecilia reticulata under laboratory *** our first experiment,we demonstrate that the response of guppies from a high predation population(Lopinot River)was dependent upon the source of disturbance cue senders(high *** predation populations).However,guppies collected from a low predation site(Upper Aripo River)exhibited similar responses to disturbance cues,regardless of the sender *** our second experiment,we used laboratory strain guppies exposed to high versus low background risk *** results show an analogous response patterns as shown for our first *** exposed to high background risk conditions exhibited stronger responses to the disturbance cues collected from senders exposed to high(***)risk conditions and guppies exposed to low risk conditions were not influenced by sender ***,our results suggest that experience with background predation risk significantly impacts both the production of and response to disturbance cues in guppies.

关键词： disturbance cues ecology of information perceived risk predator-prey interactions Trinidadian guppy

Do human activities influence survival and orientation abilities of larval fishes in the ocean?

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Integrative Zoology 2015年第1期10卷 65-82页

作者： Ulrike e.SIeBeCK jack O’CONNOR Christoph BRAUN Jeffrey M.LeIS School of Biomedical Sciences The University of QueenslandBrisbaneAustralia Ichthyology The Australian MuseumSydneyAustralia Department of environmental Studies University of Technology SydneyUltimoAustralia Institute for Marine and Antarctic Studies University of TasmaniaHobartAustralia

The larval stages of most marine fishes spend days to weeks in the pelagic environment,where they must find food and avoid predators in order to *** fish only spend part of their life history in the pelagic environment before returning to their adult habitat,for example,a coral *** sensory systems of larval fish develop rapidly during the first few days of their lives,and here we concentrate on the various sensory cues the fish have available to them for survival in the pelagic *** focus on the larvae of reef fishes because most is known about *** also review the major threats caused by human activities that have been identified to have worldwide impact and evaluate how these threats may impact larval-fish survival and orientation *** human activities negatively affect larval-fish sensory systems or the cues the fish need to ***,this could lead to decreased numbers of larvae surviving to settlement,and,therefore,to decreased abundance of adult *** we focus on species wherein the larvae and adults occupy different habitats(pelagic and demersal,respectively),it is important to acknowledge that the potential anthropogenic effects we identify may also apply to larvae of species like tuna and herring,where both larvae and adults are pelagic.

关键词： climate change larval fish pollution sensory systems teleost fish

Quantitative characterization of polyacrylamide–shale interaction under various saline conditions

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Petroleum Science 2017年第3期14卷 586-596页

作者： Samyukta Koteeswaran jack C.Pashin Josh D.Ramsey Peter e.Clark School of Chemical engineering Oklahoma State UniversityStillwater OK 74078 USA Boone Pickens School of Geology Oklahoma State University Stillwater OK 74078 USA

Interaction of polymer-containing injected fluids with shale is a widely studied phenomenon, but much is still unknown about the interaction of charged polyacrylamides such as anionic and cationic polyacrylamides with shale. The nature of interaction of charged polyacrylamides with shale is not well understood, especially from the perspective of assessing the potential for polyacrylamides to cause formation damage. Zeta potential and rheological measurements were made for Chattanooga and Pride Mountain shales suspended in polyacrylamide solutions with and without inorganic salts and tetramethyl ammonium chloride（TMAC）. The change in zeta potential and viscosity with time was recorded. The magnitude of decrease in the absolute value of zeta potential with time is indicative of adsorption of polymer on the surface of shale and serves as a measure of the extent of polymer interaction with shale. The salts that were used in this study are potassium chloride（KCl）, sodium chloride（Na Cl）. This study quantified the interaction of anionic and cationic polyacrylamide with different North American *** the experimental results, it was determined that the polyacrylamides can interact strongly with shale, particularly the cationic polyacrylamide. The objective of this study was to determine the extent of interaction of anionic and cationic polyacrylamide with each shale sample in the presence of additives such as salts.

关键词： Anionic and cationic polyacrylamides Chattanooga shale Pride Mountain shale Zeta potentialSlurry rheology

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Neuroimaging of inflammation in alcohol use disorder: a review

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作者： jack e. Davis.

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Science China(Information Sciences) 2020年第7期63卷 19-37页

作者： Dana e.FeLDMAN Katherine L.MCPHeRSON Catherine L.BIeSeCKeR Corinde e.WIeRS Peter MANZA Nora D.VOLKOW Gene-jack WANG National Institute on Alcohol Abuse and Alcoholism National Institute on Drug Abuse

Alcohol use disorder(AUD) is a global health concern associated with several *** health problems related to AUD, such as cognitive deficits, have been linked to *** use has been associated with changes in neuroimmune activity, although current literature has yielded mixed results. For example, markers of gliosis, including translocator protein 18-kDa(TSPO), proinflammatory cytokines, glutamate(Glu), and myo-inositol(mI), are disrupted in the alcohol-dependent brain. Further, neuroinflammatory-related phenomena including membrane turnover, blood brain barrier(BBB) permeability, and adenosine release have also shown alterations in AUD. However, current literature remains inconclusive about the directionality of these changes. Both in vivo and in vitro studies have provided insight on the relationship between alcohol use and neuroinflammatory processes, suggesting considerable treatment potential for alcohol use disorder and its inflammatory comorbidities. Here, we review current neuroimaging literature assessing the impacts of alcohol use on neuroimmune activity in the brain.

关键词： acetate adenosine alcohol use disorder blood brain barrier choline gliosis glutamate myoinositol neuroimaging neuroinflammation

Forests of West Virginia,U.S.A. and Shaanxi,China:a study in forest exploitation and recovery

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Journal of Forestry Research 2004年第1期15卷 49-54,J002-J003页

作者： jack e.Coster 彭鸿张秦岭 Morgantown West Virginia.U.S.A 陕西水土保持局西安710004 西北农林科技大学生命科学学院陕西杨凌712100

A review of the period of unregulated exploitation of forests in the state of West Virginia (U.S.) and in Shaanxi Province, PRC was presented. economic and ecological recovery from exploitation has been different in the two regions due to basic differences in nature of the forest and in the degree and persistence of exploitive pressures. After a century since unregulated exploitation, West Virginia forests are well on the road to management for sustainability and conservation. Shaanxi's recovery from overuse and unregulated exploitation is less certain; forests are still in the early phases of ecological recovery there. Full recovery to a period of sustainability will take a century or longer. Suggestions are made for measures needed to enhance the forest recovery. Keywords Forests - Shaanxi - West Virginia - Central China - Forest exploitation - Recovery CLC number S754 Document code A Article ID 1007-662X(2004)01-0049-06 Foundation item: The project was sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State education Ministry (2002–2004) and Shaanxi Provincial Foreign expert Bureau (2003).Biography: jack e. Coster (1935-), male, professor of West Virginia University, Morgantown, West Virginia. U.S.A.Responsible editor: Song Funan

关键词： Forests Shaanxi West Virginia Central China Forest exploitation Recovery

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Post-exascale supercomputing:research opportunities abound

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Frontiers of Information Technology & electronic engineering 2018年第10期19卷 1203-1208页

作者： Zuo-ning CHeN jack DONGARRA Zhi-wei XU Chinese Academy of engineering electrical engineering and Computer Science Department University of Tennessee Institute of Computing Technology Chinese Academy of Sciences

exascale supercomputing refers to the scientific research efforts and activities to build and use supercomputers that can perform scientific computing at the speed of exaflops,or 10^(18) floating-point(64-bit)operatio... 详细信息

关键词：计算研究机科学研究浮点操作

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