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The essential elements controlling trigeminal motoneurons during feeding lie between the trigeminal and facial motor nuclei. These include populations of neurons in the medial reticular formation and pre-motoneurons in the lateral brainstem that reorganize to generate various patterns. Orofacial sensory feedback, antidromic firing in spindle afferents and intrinsic properties of motoneurons also contribute to the final masticatory motor output. 相似文献
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Alan D. Steinman Mary OgdahlRichard Rediske Carl R. Ruetz IIIBopaiah A. Biddanda Lori Nemeth 《Journal of Great Lakes research》2008,34(1):169-188
A long-term monitoring program was initiated in 2003 to determine the ecological status of Muskegon Lake, a Great Lakes Area of Concern. This paper presents data generated from the first 3 years of the monitoring program, discusses how the data are being used to establish and justify lake restoration targets, and assesses how water quality conditions have changed over time. Between 1972 and 2005, lake-wide averages of total phosphorus and soluble reactive phosphorus from the water surface have declined from 68 to 27 μg/L and from 20 to 5 μg/L, respectively. In addition, average chlorophyll a concentrations have declined from 25 to 6 μg/L over this period, while Secchi disk depths have increased from 1.5 to 2.2 m. Wastewater diversion, and perhaps dreissenid filtering activity, is most likely responsible for these changes. However, nitrate concentrations have increased from 70 to 270 μg/L over the same time period. During 2003–2005, phytoplankton abundance and fish catch were lower in the spring compared to the summer and fall. Microcystis was the most abundant phytoplankton genus; the fish community generally was dominated by round goby (Neogobius melanostomus) in spring and summer, and sunfishes (Centrarchidae) in the fall. Dreissenid abundance was highly variable over time, but densities were low relative to Saginaw Bay. Approximately 65% of the Muskegon Lake shoreline has been hardened (i.e., physically altered). Overall, the water quality of Muskegon Lake has improved over the past 30 years, but environmental challenges still exist, including contaminated sediments, loss of natural habitat, and invasive species. 相似文献
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RS Franco J Lohmann EB Silberstein G Mayfield-Pratt M Palascak TA Nemeth CH Joiner M Weiner DL Rucknagel 《Canadian Metallurgical Quarterly》1998,101(12):2730-2740
Sickle red blood cells (RBC) are subject to a number of important cellular changes and selection pressures. In this study, we validated a biotin RBC label by comparison to the standard 51Cr label, and used it to study changes that occur in sickle cells as they age. Sickle RBC had a much shorter lifespan than normal RBC, but the two labels gave equivalent results for each cell type. A variable number of sickle, but not normal, RBC disappeared from the circulation during the first few hours after reinfusion. The number of biotinylated sickle reticulocytes was decreased by 50% after 24 h and 75% after 48 h, with a gradual decrease in the amount of reticulum per cell. The labeled sickle cells exhibited major density increases during the first 4-6 d after reinfusion, with smaller changes thereafter. A small population of very light, labeled sickle RBC was essentially constant in number after the first few days. Fetal hemoglobin (HbF) content was determined in isolated biotinylated sickle RBC after reinfusion, allowing an estimate of lifespan for RBC containing HbF (F cells) and non-F cells. The lifespan of sickle biotinylated RBC lacking HbF was estimated to be approximately 2 wk, whereas F cells survived 6-8 wk. 相似文献
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Differential contributions of majority and minority influence. 总被引:2,自引:0,他引:2
Contends that in most studies comparing majority and minority influence, there is an emphasis on influence in the sense of prevailing. Within this context, evidence exists that majorities exert more public influence and that minority influence, when it occurs, tends to operate primarily at the latent level. In the present formulation, it is proposed that the differences between majority and minority influence are more extensive once influence is considered in a broader context and that exposure to persistent minority views fosters greater thought about the issue. Furthermore, this thought tends to be divergent rather than convergent, so that people tend to be better decision makers because they attend to more aspects of the situation and reexamine premises. By contrast, it is proposed that exposure to persistent majority views fosters convergent thinking and leads to an unreflective acceptance of the majority position. Three studies by the author (1976) and by the author and J. Kwan (1985) that directly tested some of the propositions are reviewed, and the formulation is linked to available knowledge in the areas of social cognition, creativity, and problem solving both at the individual and group levels. (64 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Michael P. Nemeth 《热应力杂志》2013,36(9):873-916
An approach for synthesizing buckling results and behavior for thin balanced and unbalanced symmetric laminates that are subjected to nondestabilizing mechanical preloads, uniform heating or cooling, and elastically or totally restrained axial thermal expansion or contraction is presented. This approach uses a nondimensional analysis for infinitely long, flexurally anisotropic plates that are subjected to combined loads and is based on useful nondimensional parameters. In addition, a stiffness-weighted laminate coefficient of thermal expansion is derived and used to determine critical temperatures in terms of physically intuitive mechanical buckling coefficients, and the effects of membrane orthotropy and membrane anisotropy are included. Many results are presented for some common laminates that are intended to facilitate a structural designer's transition to the use of the generic buckling design curves that are presented in the article. Several generic buckling design curves are presented that provide physical insight into the buckling response in addition to providing useful design data. Examples are presented that demonstrate the use of the generic design curves. The analysis approach and generic results identify the effects and characteristics of laminate thermal expansion, membrane orthotropy and anisotropy, and flexural orthotropy and anisotropy in a very general and unifying manner. 相似文献
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A. Peruzzi R. Bosma O. Kerkhof P. Rosenkranz M. D. Del Campo Maldonado R. Strnad J. Nielsen M. Anagnostou T. Veliki D. Zvizdic E. Grudnewicz M. Nedea D. M. Neagu P. Steur E. Filipe I. Lobo I. Antonsen E. Renaot M. Heinonen T. Weckstrom J. Bojkovski E. Turzo-Andras S. Nemeth M. White E. Tegeler M. Dobre S. Duris A. Kartal Dogan A. Uytun V. Augevicius A. Pauzha A. Pokhodun S. Simic 《International Journal of Thermophysics》2011,32(11-12):2516-2532
The results of a EURAMET key comparison of water triple-point cells (EURAMET.T-K7) are reported. The equipment used, the measuring conditions applied, and the procedures adopted for the water triple-point measurement at the participating laboratories are synthetically presented. The definitions of the national reference for the water triple-point temperature adopted by each laboratory are disclosed. The multiplicity of degrees of equivalence arising for the linking laboratories with respect to the ??mother?? comparison CCT-K7 is discussed in detail. 相似文献
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