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A Survey of the Homotopy Properties of Inclusion of Certain Types of Configuration Spaces into the Cartesian Product

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Chinese Annals of Mathematics,Series B 2017年第6期38卷 1223-1246页

作者： Daciberg Lima GONCALVES john GUASCHI Departamento de Matematica IME-USPRua do Matao 1010CEP:05508-090Sao PauloSPBrazil Normandie Universite UNICAENLaboratoire de Mathematiques Nicolas Oresme UMR CNRS 6139CS 1403214032 Caen Cedex 5France

Let X be a topological *** this survey the authors consider several types of configuration spaces,namely,the classical(usual)configuration spaces f_n(X)and D_n(X),the orbit configuration spaces f_n^G(X)and f_n^G(X)/S_nwith respect to a free action of a group G on X,and the graph configuration spaces f_n~Γ(X)and f_n~Γ(X)/H,whereΓis a graph and H is a suitable subgroup of the symmetric group S_*** ordered configuration spaces f_n(X),f_n^G(X),f_n~Γ(X)are all subsets of the n-fold Cartesian product ∏_1~nX of X with itself,and satisfy f_n^G(X)?f_n(X)?f_n~Γ(X)?∏_1~*** A denotes one of these configuration spaces,the authors analyse the difference between A and ∏_1~nXfrom a topological and homotopical point of *** principal results known in the literature concern the usual configuration *** authors are particularly interested in the homomorphism on the level of the homotopy groups of the spaces induced by the inclusionι:A-→∏_1~nX,the homotopy type of the homotopy fibre I_ιof the mapιvia certain constructions on various spaces that depend on X,and the long exact sequence in homotopy of the fibration involving I_ιand arising from the inclusionι.In this respect,if X is either a surface without boundary,in particular if X is the 2-sphere or the real projective plane,or a space whose universal covering is contractible,or an orbit space S^k/Gof the k-dimensional sphere by a free action of a Lie group G,the authors present recent results obtained by themselves for the first case,and in collaboration with Golasi′nski for the second and third *** authors also briefly indicate some older results relative to the homotopy of these spaces that are related to the problems of *** order to motivate various questions,for the remaining types of configuration spaces,a few of their basic properties are described and proved.A list of open questions and problems is given at the end of the paper.

关键词： Configuration space Equivariant configuration space fibration Homotopy fibre K(π,1)space Braid groups

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IMAGING REDOX STATE HETEROGENEITY WITHIN INDIVIDUAL EMBRYONIC STEM CELL COLONIES

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Journal of Innovative Optical Health Sciences 2011年第3期4卷 279-288页

作者： HE N.XU RUSSELL C.ADDIS DAVIDA f.GOINGS SHOKO NIOKA BRITTON CHANCE john D.GEARHART LIN Z.LI Molecular Imaging Laboratory Department of Radiology University of PennsylvaniaSchool of Medicine PhiladelphiaPA 19104USA Institute for Regenerative Medicine and Department of Cell and Developmental Biology University of Pennsylvania School of Medicine PhiladelphiaPA 19104USA Britton Chance Laboratory of Redox Imaging johnson Research foundation Department of Biochemistry and Biophysics University of Pennsylvania School of Medicine PhiladelphiaPA 19104USA Institute of Translational Medicine and Therapeutics University of Pennsylvania PhiladelphiaPA 19104USA

Redox state mediates embryonic stem cell(ESC)differentiation and thus offers an important complementary approach to understanding the pluripotency of stem *** redox ratio(NADH/(fp t NADH)),where NADH is the reduced form of nicotinamide adenine dinucleotide and fp is the oxidizedflavoproteins,has been established as a sensitive indicator of mitochondrial redox *** this paper,we report our redox imaging data on the mitochondrial redox state of mouse ESC(mESC)colonies and the implications *** low-temperature NADH/fp redox scanner was employed to image mESC colonies grown on a feeder layer of gamma-irradiated mouse embryonicfibroblasts(MEfs)on glass cover *** result showed significant heterogeneity in the mitochondrial redox state within individual mESC colonies(size:~200-440μm),exhibiting a core with a more reduced state than the *** more reduced state positively correlates with the expression pattern of Oct4,a well-established marker of *** observation is thefirst to show the heterogeneity in the mitochondrial redox state within a mESC colony,suggesting that mitochondrial redox state should be further investigated as a potential new biomarker for the stemness of embryonic stem cells.

关键词： Redox imaging pluripotency NADH flavoproteins redox ratio

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Analytical framework Model for Capacity Needs Assessment and Strategic Capacity Development within the Local Government Structure in Tanzania

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Open Journal of Soil Science 2014年第13期4卷 502-508页

作者： john f. Kessy Abiud Kaswamila Department of forest Economics Sokoine University of Agriculture Morogoro Tanzania Department of Geography University of Dodoma Dodoma Tanzania

This is a methodological paper prepared by senior academicians, researchers and consultants from renowned universities in Tanzania. The paper provides insights as to how best development agents can approach the challenge of capacity needs assessment and development of capacity building programs in the context of the local government structure in Tanzania. The paper is of original nature and is based on author’s accumulated knowledge and practice in conducting capacity assessments and developing capacity building programs in Tanzania. The paper describes what can be considered to be best practices in conducting participatory capacity assessment through consultative processes which involves most of the key actors who would be engaged in implementing proposed interventions. The paper puts forward an analytical model for capacity assessment and program development in the Tanzanian context. The main features of the model can be summarized as participatory capacity assessment, strategic capacity building program development and complementarity through synergy building with like-minded stakeholders. The operational modality for utilizing the model in developing capacity building programs which among other components has monitoring and evaluation aspects is included. It is recommended that practitioners and development agents should test the model in their working environments to realize its potential benefits including program ownership by stakeholders.

关键词： Capacity Assessment Local Government Structure Tanzania

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Selling :building partnerships 3rd ed. 3rd ed.

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1998年

作者： Bart A. Weitz Stephen B. Castleberry john f. Tanner Jr

来源：畅想之星图书光盘版（南... 评论

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Ultra high sensitivity Charde Coupled Devices（CCD）

Ultra high sensitivity Charde Coupled Devices（CCD）

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中国物理学会光散射专业委员会成立十周年暨第六届学术会议

作者： john f Clarke Spex Industries Inc Edison NJ USA B.Sc.Ph.D

＜正＞The SPEX Spectrum One CCD is a stats-of-the-art,Z-D detector that excels at very low-light level applications reaniring the utmost *** has the added advantage of enhanced red response making it ideal for

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Repeat Rf Ablation of C2 and Third Occipital Nerves for Recurrent Occipital Neuralgia and Cervicogenic Headaches

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World Journal of Neuroscience 2016年第4期6卷 236-242页

作者： john f. Hamer Traci A. Purath Oak Brook IL USA Purath Headache and Neurology Greenfield WI USA

Objective: To address the degree and duration of pain relief from recurrent cervicogenic headaches and/or occipital neuralgia following retreatment with radiofrequency ablation of the C2 dorsal root ganglion and/or third occipital nerves;to review outcomes including duration and degree of pain relief;to evaluate procedure’s complication rate and patient’s willingness to repeat the procedure;to compare effectiveness of the most recent Rf ablation to patient’s first Rf ablation. Methods: This is a single-center retrospective observational study of 23 patients with recurrent cervicogenic headaches and/or occipital neuralgia treated with repeated Rf ablation of the C2 dorsal root ganglion and/or third occipital nerves. All patients receiving treatment from January 2010 to July 2014 are included in this single site retrospective study. This is an IRB approved medical chart review study. Results: 22 of 23 patients underwent follow-up. An average of 86.5% of participants reported pain relief on average of 25.4 weeks at time of follow-up. 41% reported side effects including suboccipital hyperesthesia and/or ear discomfort, 95% reported willingness to repeat the procedure again if severe symptoms recurred, 59% of patients reported the most recent Rf ablation had the same results as the first, 32% reported the most recent Rf was the most effective, and 9% reported that the first Rf was the most effective. Conclusion: Repeated Rf ablation is a feasible option for recurrent cervicogenic headaches and/or occipital neuralgia. Effectiveness of repeat intervention is the same or better than the first ablation. Though there was a higher likelihood of side effects including suboccipital neuralgia and/or ear discomfort on repeat treatment, the side effects were generally well tolerated.

关键词： Occipital Neuralgia Cervicogenic Headache Radiofrequency Ablation

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Comparison of the Kobayashi-Royden and Sibony metrics on ring domains

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Science China Mathematics 2009年第12期52卷 2610-2616页

作者： fORN■SS john Erik Department of Mathematics University of MichiganAnn ArborMichigan 48109USA

In this paper we show that the Kobayashi-Royden metric and the Sibony metric are different on ring domains,i.e.,the difference of two concentric balls,in higher dimension.

关键词： Kobayashi-Royden metric Sibony metric ring domain 32f45 32U05

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Cross inhibition improves activity selection when switching incurs time costs

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Current Zoology 2015年第2期61卷 242-250页

作者： James A. R. MARSHALL Angelique fAVR EAU-PEIGN Lutz fROMHAGE john M. MCNAMARA Liarme f. S. MEAH Alasdair I. HOUSTON Department of Computer Science and University of Sheffield Sheffield S 1 4DP UK INRA UMR791 Modelisation Systemique Appliquee aux Ruminants F-75005 Paris France Department of Biological and Environmental Science P.O. Box 35 FI-40014 University of Jyvaskyla Finland School of Mathematics University of Bristol University Walk Bristol BS8 1TW UK School of Biological Sciences University of Bristol Bristol Life Sciences Building 24 Tyndall Avenue Bristol BS8 1TQ UK AgroParisTech UMR Modelisation Systemique Appliquee anx Ruminants F-75005 Paris France

We consider a behavioural model of an animal choosing between two activities, based on positive feedback, and exa- mine the effect of introducing cross inhibition between the motivations for the two activities. While cross-inhibition has pre- viously been included in models of decision making, the question of what benefit it may provide to an animal＇s activity selection behaviour has not previously been studied. In neuroscience and in collective behaviour cross-inhibition, and other equivalent means of coupling evidence-accumulating pathways, have been shown to approximate statistically-optimal decision-making and to adaptively break deadlock, thereby improving decision performance. Switching between activities is an ongoing decision process yet here we also find that cross-inhibition robustly improves its efficiency, by reducing the frequency of costly switches between behaviours .

关键词： Crossinhibition Geometric framework foraging Activity selection Neuroscience Behaviour

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Validation of a discrete element model using magnetic resonance measurements

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Particuology 2009年第4期7卷 297-306页

作者： Christoph R.Müller Stuart A.Scott Daniel J.Holland Belinda C.Clarke Andrew J.Sederman john S.Dennis Lynn f.Gladden Department of Chemical Engineering and Biotechnology University of CambridgePembroke StreetCambridge CB2 3RAUnited Kingdom

The discrete element model （DEM） is a very promising modelling strategy for two-phase granular systems. However, owing to a lack of experimental measurements, validation of numerical simulations of two-phase granular systems is still an important issue. In this study, a small two-dimensional gas- fluidized bed was simulated using a discrete element model. The dimensions of the simulated bed were 44mm × 10mm × 120 mm and the fluidized particles had a diameter dp = 1.2 mm and density ρp = 1000 kg/m^3. The comparison between DEM simulations and experiments are performed on the basis of time-averaged voidage maps. The drag-law of Beetstra et al. [Beetstra, R., van der Hoef, M.A., ＆ Kuipers,J. A. M. （2007b）. Drag force of intermediate Reynolds number flow past mono- and bidispersed arrays of spheres. AIChE Journal, 53,489-501 ] seems to give the best results. The simulations are fairly insensitive to the coefficient of restitution and the coefficient of friction as long as some route of energy dissipation during particle-particle and particle-wall contact is provided. Changing the boundary condition of the gas phase at the side-walls from zero-slip to full-slip does not affect the simulation results. Care is to be taken that the cell sizes are chosen so that a reasonable number of particles can be found in a fluid cell.

关键词： Discrete element modelling Magnetic resonance imaging Voidage Gas-fluidized beds

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Huanglongbing:An overview of a complex pathosystem ravaging the world's citrus

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Journal of Integrative Plant Biology 2016年第4期58卷 373-387页

作者： john V.da Graca Greg W.Douhan Susan E.Halbert Manjunath L.Keremane Richard f.Lee Georgios Vidalakis Hongwei Zhao Texas A&M University--Kingsville Citrus Center WeslacoTexas 78599USA Department of Plant Pathology and Microbiology University of CaliforniaRiversideCalifornia 92521USA florida Department of Agriculture and Consumer Services Division of Plant IndustryP.O.Box 147100GainesvilleFlorida 32614USA USDA ARS National Clonal Germplasm Repository for Citrus and Dates RiversideCalifornia 92507USA College of Plant Protection Nanjing Agricultural UniversityNanjing 210095China

Citrus huanglongbing（HLB） has become a major disease and limiting factor of production in citrus areas that have become infected. The destruction to the affected citrus industries has resulted in a tremendous increase to support research that in return has resulted in significant information on both applied and basic knowledge concerning this important disease to the global citrus industry. Recent research indicates the relationship between citrus and the causal agent of HLB is shaped by multiple elements, in which host defense responses may also play an important role. This review is intended to provide an overview of the importance of HLB to a wider audience of plant biologists. Recent advances on host-pathogen interactions, population genetics and vectoring of the causal agent are discussed.

关键词： Citrus greening Diaphorina citri host response Huanglongbing(HLB) psyllid vectors

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