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DETERMINANTS OF STRUCTURE IN AQUATIC NON-PELAGIC PROTOZOAN COMMUNITIES

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Chinese Journal of Oceanology and Limnology 1993年第3期11卷 215-228页

作者： john cairns Jr Paul V.McCormick University Center for Environmental and Hazardous Materials Studies Virginia Polytechnic Institute and State University Blacksburg Virginia 24061 U.S.AUniversity Center for Environmental and Hazardous Materials Studies Virginia Polytechnic Institute and State University Blacksburg Virginia 24061 U.S.AUniversity Center for Environmental and Hazardous Materials Studies Virginia Polytechnic Institute and State University Blacksburg Virginia 24061 U.S.A

Although microbes have traditionally been used as models for testing ecological theory, research on the organization of these communities has largely been isolated from other areas of community ecology. Early studies indicated that microbial populations can form dynamic, interacting assemblages. Observations of distributional patterns suggest that certain deterministic forces regulate community structure. It appears that protozoans are tolerant of a wide range of environmental conditions although evidence for this is largely based on gross environmental analyses. Laboratory studies have suggested the importance of negative and positive biotic interactions in determining community membership, but little field evidence for this exists. The importance of transport processes in controlling community composition is being increasingly recognized. All three types of processes likely act to regulate the colonization and successional dynamics of these communities. A simple model is presented to promote the

关键词： determinants structure protozoan communities

Prospects for the continued development of environmentally-realistic toxicity test susing microorganisms

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Journal of Environmental Sciences 1993年第3期5卷 253-268页

作者： john cairns,Jr. Paul V.McCormick Scott E.Belanger Department of Biology and University Center for Environmental and Hazardous Materials Studies Virginia Polytechnic Institute and State UniversityBlacksburgVirginia 24061-0415U.S.A. Department of Biology Elizabethtown CollegeElizabethtownPennsylvania-17022-2298U.S.A.and Senior Research AssociateUniversity Center for Environmental and Hazardous Materials StudiesVirginia Polytechnic Institute and State UniversityBlacksburgVirginia-24061-0415U.S.A. Stream Ecosystem Research Section Environmental Safety DepartmentThe Procter and Gamble CompanyCincinnatiOhio-45217U.S.A.

The focus of environmental regulations has changed significantly since the introduction of the bioassay as a standard means of assessing environmental *** in this change is an increasing emphasis on protecting the integrity of natural ecosystems,which incorporate community-and system-level properties as well as organismal and population ***,support for the use of multispecies testing has widened to include not only ecologists in academia but environmental scientists in the regulatory and industrial sector as *** reason for this trend is clear:the additional environmental realism gained from tests utilizing communities of organisms allows for greater insight into the potential hazard of chemicals and other forms of human activity to natural ecosystems that cannot be obtained from single species tests *** of the problems cited for multispecies testing early in their evolution as a hazard assessment tool have been refuted or *** particular,the use of natural microbial communities minimizes several shortcomings typically associated with multispecies toxicity *** discussion includes the utility of microcosm and mesocosm tests using aquatic microbial communities as hazard assessment tools in conjunction with accumulating information on their performance in toxicity testing *** increasing body of experimental evidence supports an expansion in the use of these tests for a variety of regulatory and research purposes.A shift in research focus is needed,however,to answer remaining questions and further refine standard protocols for these valuable ecotoxicological tools.

关键词： environmentally-realistic toxicity tests microorganisms.

Macroinvertebrate　assemblages　of　surface　mine　wetlands　of　Southwest　Virginia，USA

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Journal of Environmental Sciences 1996年第1期8卷 1-14页

作者： David H.Jones Robert B. Atkinson john cairns,Jr.(Department of Biology,Virginia Polytechnic Institute and State University, Blacksburg,Virginia 24061 USA) Dept Biol Virginia Poly Inst Blacksburg VA 24061 United States

The focus of this study was to investigate the macroinvertebrate community in surface mine wetlands. Nine wetlands were sampled for macroinvertebrates from July 1993 through May *** sites represented a range of physical,chemical, and biological parameters. Macroinvertebrates were found in all sites;a total of 14 orders, 40 families,and 70 genera were identified in the samples. Insects were the most common invertebrates,and most functional feeding groups were represented. Predators dominated with 63% of the taxa, followed by the collector/gathers with 20%,shredders 14%, and scrapers 3%. Sites differed in the number of taxa inhabiting *** ranged from 10 genera to *** lowest richness was found in two seasonal wetlands that were dry for the majority of the year. A permanently flooded site with no water quality problems and a dense growth of aquatic plants had the highest richness.

关键词： macroinvertebrate assemblages surface mine wetlands wetland faunas.

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癌症的起因

国际肿瘤学杂志 1982年第2期28卷 83-85页

作者： john cairns 柯杨

不同人群倾向于罹患不同的癌症。第三世界国家居民多发肝癌,西方国家居民好发乳腺癌和结肠癌,日本人则高发胃癌。一些国家癌症发病率一代一代发生改变,而移民却倾向于罹患新定居国家的特殊好发癌症,这可能是由于饮食、生活习惯和环境因... 详细信息

不同人群倾向于罹患不同的癌症。第三世界国家居民多发肝癌,西方国家居民好发乳腺癌和结肠癌,日本人则高发胃癌。一些国家癌症发病率一代一代发生改变,而移民却倾向于罹患新定居国家的特殊好发癌症,这可能是由于饮食、生活习惯和环境因素不同所造成的。此外,皮肤癌和肺癌与单一因素(日晒和吸烟)有关,而其他一些常见癌症的病因则不甚清楚。当代核酸化学技术的发展,已能分辨癌细胞及与其对应之正常细胞在核酸顺序和基因表达上的区别。从这一点出发,也许能够阐明肿瘤发生过程的各个步骤。本综述旨在分析事实资料,并对人类癌症分子生物学问题作某些推论。实验致癌作用有许多方法能在实验动物中诱发癌瘤。将动物作为靶体暴露于可损害DNA

关键词：癌症死亡人数 DNA 皮肤癌患者修复缺陷染色体重排

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关于水质管理选择方法的评价

环境科学动态 1986年第5期 10-12页

作者： john cairns Jr.

引言直至约15年前,生态学意识才成为工业化国家的主要特点.这种突然发展似乎是由于社会废物从各种方式和在一些地方超出了环境的净化能力而产生的结果.环境突变是来自自然系统的正确的信号所致,也就是说,社会上废物的耐受阈值涉及到几... 详细信息

引言直至约15年前,生态学意识才成为工业化国家的主要特点.这种突然发展似乎是由于社会废物从各种方式和在一些地方超出了环境的净化能力而产生的结果.环境突变是来自自然系统的正确的信号所致,也就是说,社会上废物的耐受阈值涉及到几乎世界的每个地方.如Woodwell(1984)所示。

关键词：净化能力水质管理生态学理论最佳条件应用因子微生态系工程师学会接收系统质量控制系统学术讨论会

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逐步致癌

国际肿瘤学杂志 1984年第2期11卷 105-107页

作者： john cairns ,Jonothan Logan ,孙即昆

大多数人癌是多年逐步变化才产生的。如宫颈癌,常首先出现异常细胞(宫颈细胞发育不良)的扩展性克隆,此种克隆往往退化消失,但其中有时形成更不正常的细胞群(原位癌),其中电包括形成真正的浸润癌。这样,细胞就脱离了机体的控制(此种控制... 详细信息

大多数人癌是多年逐步变化才产生的。如宫颈癌,常首先出现异常细胞(宫颈细胞发育不良)的扩展性克隆,此种克隆往往退化消失,但其中有时形成更不正常的细胞群(原位癌),其中电包括形成真正的浸润癌。这样,细胞就脱离了机体的控制(此种控制在正常的上皮组织中起作用),松弛了对分化的控制,并消除了对细胞寿命的限制。由于我们对多细胞系统的生长和形成的分子生物学毫无了解,因而也就不能弄清哪些生化改变能赋予一细胞

关键词：纤维细胞 DNA 瘤基因细胞群肿瘤病毒致癌性病毒逆转录病毒细胞株

Asynopsis of the book Striking a balance :improving stewardship of marine areas

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Journal of Environmental Sciences 2000年第4期12卷 506-509页

作者： cairns Jr., john Virginia Polytechnic Institute and State University 美国 Blacksburg VA 240 6 1

Reviews the book `Striking a Balance: Improving Stewardship of Marine Areas.'

关键词： Asynopsis of the book Striking a balance improving stewardship of marine areas

SERVICE VALUE NETWORKS:INTO PRACTICE

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Journal of Systems Science and Systems Engineering 2007年第4期16卷 414-423页

作者： john HAMILTON Director of E-Business James Cook UniversityCairns4870Australia

Modeling a business to match its customer perceived （and customer desired） outcomes, remains an on-going task. This paper considers shows how a service value networks （SVNs） approach may be engaged to model, and deliver, understanding of the front-end business and its direct engagement with its immediate （or front-end） customers. These front-end customers may be either：（1） its off-line, in-store customers - engaging directly with the business sales staff （or representative）, or-（2） its on-line, virtual customers - engaging with the business via internet or remote access. In this situation, both the business, and the customer draw upon their respective viewpoints, and both sides influence the interaction. External to these business and customer influences are additional factors that capture the immediate and broader global effects - termed environmental effects. These three business-customer engagement areas of influence are captured by a SVN SEM approach. Without a business-customer encounter of some kind the likelihood of a services business, and a prospecting customer, successfully engaging in an exchange process is reduced. This exchange may be a physical, and/or services exchange, and/or an information and/or ideas exchange. To the business, this encounter is, in effect, a trade, and as a result, the business targets acquiring an economic exchange that will ultimately deliver a net positive economic outcome. To the customer, external and internal information feeds, servicing, perceived value, and satisfaction, are key encounter drivers. SVNs offers a new way to understand the business-customer encounter, and to then utilize this acquired knowledge to either：（1） build a strategic management model, or （2） reengineer its business networks, and to then create a re-positioned, more customer-aligned business operation - one that is capable of delivering win - win, competitive business-customer solutions.

关键词： Service value networks alignment structural equation modeling

BENCHMARKING ON-LINE SERVICES INDUSTRIES

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Journal of Systems Science and Systems Engineering 2006年第1期15卷 48-69页

作者： john HAMILTON Director of E-Business James Cook University Cairns 4870 Australia

The Web Quality Analyser (WQA) is a new benchmarking tool for industry. It has been extensively tested across services industries. Forty five critical success features are presented as measures that capture the user’s perception of services industry websites. This tool differs to previous tools, in that it captures the information technology (IT) related driver sectors of website performance, along with the marketing-services related driver sectors. These driver sectors capture relevant structure, function and performance components. An ‘on-off’ switch measurement approach determines each component. Relevant component measures scale into a relative presence of the applicable feature, with a feature block delivering one of the sector drivers. Although it houses both measurable and a few subjective components, the WQA offers a proven and useful means to compare relevant websites. The WQA defines website strengths and weaknesses, thereby allowing for corrections to the website structure of the specific business. WQA benchmarking against services related business competitors delivers a position on the WQA index, facilitates specific website driver rating comparisons, and demonstrates where key competitive advantage may reside. This paper reports on the marketing-services driver sectors of this new benchmarking WQA tool.

关键词： Benchmarking performance website service analysis compare