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Long-term monitoring of cycles in Clethrionomys rutilus in the Yukon boreal forest

Integrative Zoology 2024年第1期19卷 27-36页

作者： Charles J.krebs Alice J.KENNEY B.Scott GILBERT Rudy BOONSTRA Department of Zoology University of British ColumbiaVancouverBritish ColumbiaCanada Renewable Resources Management Program Yukon UniversityWhitehorseYukonCanada Department of Biological Sciences University of Toronto ScarboroughTorontoOntarioCanada

Baseline studies of small rodent populations in undisturbed ecosystems are *** report here 50 years of mon-itoring and experimentation in Yukon of a dominant rodent species in the North American boreal forest,the red-backed vole Clethrionomys *** voles breed in summer,weigh 20–25 g,and reach a maximum density of 20 to 25 per *** populations have shown consistent 3–4-year cycles for the last 50 years with the only change being that peak densities averaged 8/ha until 2000 and 18/ha since that *** the last 25 years,we have measured food resources,predator numbers,and winter weather,and for 1-year social interactions,to estimate their contribution to changes in the rate of summer increase and the rate of overwinter *** these potential limiting factors could contribute to changes in density,and we measured their relative contributions statistically with multiple *** rate of winter decline in density was related to both food supply and winter *** rate of summer increase was related to summer berry crops and white spruce cone *** measure of predator numbers was related to winter or summer changes in vole *** was a large signal of climate change effects in these *** is no density dependence in summer population growth and only a weak one in winter population *** of our results provide a clear understanding of what generates 3–4-year cycles in these voles,and the major missing piece may be an understanding of social interactions at high density.

关键词： boreal forest climate change density dependence population cycles predation winter severity

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Many faces of neuronal activity manipulation in Drosophila

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Neural Regeneration Research 2025年第9期20卷 2574-2576页

作者： Amber krebs Steffen Kautzmann Christian Klämbt Institut für Neuro-und Verhaltensbiologie MünsterGermany

Animals exhibit complex responses to external and internal *** information is computed by interconnected neurons that express numerous ion channels,which modulate the neuronal membrane *** can neuronal activity orchestrate complex motor patterns or allow learning from previous experience?To answer such questions,we need the ability not only to record,but also to modulate neuronal activity in both space(e.g.,neuronal subsets)and time.

关键词： manipulation potential. neuronal

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生产准备时间缩短一半

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现代制造 2024年第8期 30-30,32页

作者： Lars Rödel Jonas krebs Gregor Müller Timo Denner 不详

在生产准备工作实现自动化之后,才能实现节约生产成本的目标。而利用弗劳恩霍夫IPA生产技术和自动化研究所开发的“设计链(Designchain)”系统可实现生产准备的自动化。当前,虽然经济形势不容乐观,但Ceratizit公司的订单合同依然比较充... 详细信息

在生产准备工作实现自动化之后,才能实现节约生产成本的目标。而利用弗劳恩霍夫IPA生产技术和自动化研究所开发的“设计链(Designchain)”系统可实现生产准备的自动化。当前,虽然经济形势不容乐观,但Ceratizit公司的订单合同依然比较充足。究其原因,是由于此前受全球疫情影响,Ceratizit公司忘记了如何快速高效地处理客户合同订单,还是因为供应链受到干扰而出现订单积压?

关键词：自动化研究所供应链设计链生产准备时间合同订单生产准备工作节约生产订单合同

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Simulation-Based Analysis and Intuitive Visualization of the Cutting Edge Load in Micromilling of Hardened Steel

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Engineering（科研） 2012年第9期4卷 532-539页

作者： Petra Kersting Dirk Biermann eugen.krebs Institute of Machining Technology Dortmund Germany

The precise micromanufacturing of complex dies with small structures for sheet-bulk metal forming is a challenge due to the high hardness of the materials to be machined. Experiments have shown that micromilling of these difficult-to-machine materials is possible despite of their high hardness. Nevertheless, the higher wear of the tools plays a decisive role. When implementing the machining task as five-axis process, it is possible to control the wear distribution by tilting the milling tools. In this paper, a simulation system is presented which determines the loads acting on the cut- ting edge with regard to different criteria, e.g., the machined material or the effective impulse. Based on this knowledge, it is possible to design the milling process to minimize the tool wear and thereby to increase the lifetime of the milling tools. In order to show the applicability of the simulation system, test workpieces were machined and the experimental results are compared to the simulation data.

关键词： Simulation Visualization Micromilling Tool Wear

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One hundred years of population ecology:Successes,failures and the road ahead

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Integrative Zoology 2015年第3期10卷 233-240页

作者： Charles J.krebs Department of Zoology University of British ColumbiaVancouverCanada and Institute for Applied EcologyUniversity of CanberraCanberraAustralia

Population ecology is the most mature of the three subdisciplines of ecology partly because it has a solid mathematical foundation and partly because it can address the primary questions of distribution and abundance with experimental *** there is much left to do to integrate our population knowledge into community and ecosystem ecology to help address the global issues of food security and the conservation of *** different approaches are now being developed to bring about this integration and much more research will be necessary to decide which if any will be most useful in achieving our goals of explaining the changes we see in the distribution and abundance of animals and *** web ecology would appear to be the best approach at present because it uses the detailed information of the population ecology of particular species in combination with data on consumer-resource interactions to apply to the applied problems of biodiversity conservation,food security,pest management and disease *** we can use our understanding of population ecology to address the practical problems of our time in a creative way,we will benefit both the human population and the Earth’s *** remains to be done.

关键词： abundance geographic distributions history of ecology population models

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Rodent biology and management

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Integrative Zoology 2014年第3期9卷 229-230页

作者： Charles krebs Department of Zoology University of British Columbia Vancouver BCCanada

Rodent species comprise about 42%of the Earth’s mammal biodiversity,with 2277 species and others still not *** such they are key species in many ecosystems as herbivores,seed eaters and seed dispersers,and prey for many *** of rodent biology and population dynamics goes on with little notice by humans,but a small number of rodent species are major pests for agriculture or reservoirs for diseases that can be transmitted to *** of their typically small size and rapid turnover,rodents are excellent subjects both for laboratory and field *** students can study rodent biology knowing that in the time frame of 3 years they can ask and answer interesting scientific questions.

关键词： diseases reservoirs typically

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Rodents galore:Third International Conference on Rodent Biology and Management

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Integrative Zoology 2006年第4期1卷 194-195页

作者： Charles J.krebs Department of Zoology University of British ColumbiaVancouverCanada

The Third International Conference on Rodent Biology and Management was held in Hanoi,Vietnam,from 28 August to 1 September 2006,with 130 scientists from 32 countries *** focus of the conference was to bring together pure and applied scientists dealing with rodent ecology,rodent pests,and rodent conservation in one framework to encourage scientific *** conference followed highly successful conferences in Beijing in 1998 and in Canberra in 2003.

关键词： dealing Management encourage

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Palatability and profitability of co-occurring seeds alter indirect interactions among rodent-dispersed trees

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Integrative Zoology 2022年第2期17卷 206-216页

作者： Zhishu XIAO Marcel HOLYOAK Charles J.krebs Xiaoqun HUANG State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture Institute of ZoologyChinese Academy of SciencesChina University of Chinese Academy of Sciences BeijingChina Department of Environmental Science and Policy University of CaliforniaDavisUSA Department of Zoology University of British ColumbiaVancouverCanada

Beyond direct species interactions,seed dispersal is potentially affected by indirect seed–seed interactions among co-occurring nut-bearing trees which are mediated by scatter-hoarding animals as shared seed dispersers.A relevant question in such systems is to what extent different functional traits related to food palatability and profitability affect the kinds of indirect interactions that occur among co-occurring seeds,and the consequences for seed *** used field experiments to track seed dispersal with individually tagged seeds in both monospecific and mixed seed *** measured indirect effects based on 3 seed–seed species pairs from the family Fagaceae with contrasting seed size,tannin level,and dormancy in a subtropical forest in Southwest *** all else was equal,the presence of adjacently placed seeds with contrasting seed traits created different indirect effects measured through a variety of dispersal-related *** mutualism was reciprocal due to increasing seed dispersal in mixed seed patches with mixed differences in seed tannins and ***,differences in either seed size or dormancy in co-occurring adjacently placed seeds caused apparent competition with reduced seed removal or seed dispersal(distance)in at least one *** study supports the hypothesis that different functional traits related to food palatability and profitability in co-occurring seeds modify foraging decisions of scatter-hoarding animals,and subsequently cause indirect effects on seed dispersal among rodent-dispersed *** conclude that such indirect effects mediated by shared seed dispersers may act as an important determinant of seed dispersal for co-fruiting animal-dispersed trees in many natural forests.

关键词： dispersal distance functional trait scatter-hoarding rodents seed dispersal trait-mediated indirect interactions

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Prognostic value of additional pathological variables for longterm survival after curative resection of rectal cancer

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World Journal of Gastroenterology 2006年第28期12卷 4565-4568页

作者： Bojan krebs Miran Kozelj Rajko Kavalar Borut Gajzer Eldar M Gadzijev Department for abdominal surgery Teaching Hospital MariborLjubljanska ulica 52000 MariborSlovenia Department for abdominal surgery Teaching Hospital MariborLjubljanska ulica 52000 MariborSlovenia Department of PathologyTeaching Hospital MariborLjubljanska ulica 52000 MariborSlovenia

AIM： To evaluate the prognostic value of some pathological variables in rectal cancer survival. METHODS： 247 patients who underwent curative resection of rectal cancer were included in the study. The influence on survival of five pathological variables （histopathological tumor type, histopathological tumor grade differentiation, blood vessel invasion, perineural invasion and lymphatic invasion） was assessed using statistical analyses. RESULTS： Overall 5-year survival was 71.2%. Univariate analysis of all tested variables showed an effect on survival but only the effect of lymphatic invasion was statistically significant. At stages three and four it had a negative effect on survival （P = 0.0212）. Lymphatic invasion also significantly affected cancer related survival in multivariate analysis at stages three and four. At lower stages （stage 0, stage 1 and stage 2） multivariate analysis showed a negative effect of perineural invasion on cancer related survival. CONCLUSION： Patients with lymphatic and perineural invasion have a higher risk for rectal cancer related death after curative resection. Examination of these variables should be an important step in detecting patients with a poorer prognosis.

关键词： Rectum Cancer Prognosis Survival Lymphatic invasion Perineural invasion

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Exploring new avenues in high repetition rate table-top coherent extreme ultraviolet sources

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Light(Science & Applications) 2015年第1期4卷 231-236页

作者： Steffen Hadrich Manuel krebs Armin Hoffmann Arno Klenke Jan Rothhardt Jens Limpert Andreas Tunnermann Friedrich-Schiller-Universitat Jena Institute of Applied PhysicsAbbe Center of PhotonicsAlbert-Einstein-Straße 1507745 JenaGermany Helmholtz-Institute Jena Frobelstieg 307743 JenaGermany Fraunhofer Institute for Applied Optics and Precision Engineering Albert-Einstein-Straße 707745 JenaGermany

The process of high harmonic generation(HHG)enables the development of table-top sources of coherent extreme ultraviolet(XUV)*** these are now matured sources,they still mostly rely on bulk laser technology that limits the attainable repetition rate to the low kilohertz ***,many of the emerging applications of such light sources(e.g.,photoelectron spectroscopy and microscopy,coherent diffractive imaging,or frequency metrology in the XUV spectral region)require an increase in the repetition ***,these sources are operated with a multi-MHz repetition rate and deliver a high photon flux *** far,this regime has been solely addressed using passive enhancement cavities together with low energy and high repetition rate ***,a novel route with significantly reduced complexity(omitting the requirement of an external actively stabilized resonator)is demonstrated that achieves the previously mentioned demanding parameters.A krypton-filled Kagome photonic crystal fiber is used for efficient nonlinear compression of 9 μJ,250 fs pulses leading to,7 μJ,31 fs pulses at 10.7 MHz repetition *** compressed pulses are used for HHG in a gas *** attention is devoted to achieving phase-matched(transiently)generation yielding.10^(13) photons s^(-1)(.50 μW)at 27.7 *** new spatially coherent XUV source improved the photon flux by four orders of magnitude for direct multi-MHZ experiments,thus demonstrating the considerable potential of this source.

关键词： coherent extreme ultraviolet sources high average power high harmonic generation nonlinear compression ultrafast laser

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