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Firm Basis (firm + basis)
Selected AbstractsFact, Truth, and Text: The Quest for a Firm Basis for Historical Knowledge Around 1900HISTORY AND THEORY, Issue 3 2003Rolf Torstendahl The object of this essay is to discuss two problems and to present solutions to them, which do not quite agree with what is generally said of them. The first problem concerns the history of methods for reaching firm historical knowledge. In three methodological manuals for historians, written by J. G. Droysen, E. Bernheim, and C.-V. Langlois and C. Seignobos and first published in the late nineteenth century, the task of the historian was said to be how to obtain firm knowledge about history. The question is how this message should be understood. The second problem concerns the differences between the three manuals. If their common goal is firm historical knowledge, are there any major differences of opinion? The answer given in this article is yes, and the ground is sought in their theories of truth. [source] Steady- and unsteady-state lumped parameter modelling of tritium and chlorofluorocarbons transport: hypothetical analyses and application to an alpine karst aquiferHYDROLOGICAL PROCESSES, Issue 17 2005N. Nur Ozyurt Abstract Determination of a groundwater's mean residence time with the aid of environmental tracers is common in hydrogeology. Many of the lumped parameter (LP) applications used for this purpose have been based on steady-state models. However, the results may be misleading if a steady LP model is used to simulate the environmental tracer transport in an unsteady aquifer. To test this hypothesis, the results of steady and unsteady versions of several LP models were evaluated theoretically and in an alpine karst aquifer case by using tritium, oxygen-18 and chlorofluorocarbons (CFCs). The results reveal that the mean residence times obtained may be significantly different between the steady and unsteady versions of the same model. For the karst aquifer investigated, a serially connected exponential and a plug flow model were run under unsteady conditions. It is shown that outflux calibration with an unsteady model provides a firm basis in evaluating the results of models. An outflux-calibrated unsteady model predicted reasonably the observed series of water isotopes. The calibrated model's CFCs output overpredicts the observed concentrations, probably because of the time lag in the unsaturated zone of the alpine karst aquifer. Copyright © 2005 John Wiley & Sons, Ltd. [source] Fibroblast growth factor-2 mRNA expression in the brainstem and spinal cord of normal and chronic spinally transected urodelesJOURNAL OF NEUROSCIENCE RESEARCH, Issue 15 2008Marie Moftah Abstract Descending pathways in the spinal cord of adult urodele amphibians show a high regenerative ability after body spinal cord transection; regenerated axons regrow into the transected spinal cord, and hindlimb locomotor recovery occurs spontaneously. Little is currently known about the molecular basis of spinal cord regeneration in urodeles, but it is believed that fibroblast growth factor-2 (FGF2) may play an important role by inducing proliferation of neural progenitor cells. The aim of our study, using in situ hybridization in adult Pleurodeles waltlii, was twofold: 1) to document FGF2 mRNA expression pattern along the brainstem-spinal cord of intact salamanders and 2) to investigate the changes in this pattern in animals unable to display hindlimb locomotor movements and in animals having fully recovered hindlimb locomotor activity after body spinal cord transection. This design establishes a firm basis for further studies on the role of FGF2 in functional recovery of hindlimb locomotion. Our results revealed a decreasing rostrocaudal gradient in FGF2 mRNA expression along the brainstem-spinal cord in intact animals. They further demonstrated a long-lasting up-regulation of FGF2 mRNA expression in response to spinal transection at the midtrunk level, both in brainstem and in the spinal cord below the injury. Finally, double immunolabeling showed that FGF2 was up-regulated in neuroglial, presumably undifferentiated, cells. Therefore, we propose that FGF2 may be involved in cell proliferation and/or neuronal differentiation after body spinal cord transection in salamander and could thus play an important role in functional recovery of locomotion after spinal lesion. © 2008 Wiley-Liss, Inc. [source] BARBARIAN PIRACY AND THE SAXON SHORE: A REAPPRAISALOXFORD JOURNAL OF ARCHAEOLOGY, Issue 1 2005A.F. PEARSON Summary. The tradition of Saxon and other Continental piracy is one of the longest standing tenets of Romano-British studies. It may also be one of its greatest myths, which owes more to its considerable antiquarian pedigree than to any firm basis in fact. This paper reassesses Roman military strategy around the British coast, and suggests that the ,Saxon Shore Forts' and other coastal installations played a more significant economic and logistical role than is often appreciated. Moreover, the idea that each monument fulfilled a single, dedicated function is argued to be too simplistic: instead it is proposed that individual forts served in various capacities during their operational lifetime, and quite possibly not those for which they were originally conceived. [source] A new metabolite of nodakenetin by rat liver microsomes and its quantification by RP-HPLC methodBIOMEDICAL CHROMATOGRAPHY, Issue 2 2010Peng Zhang Abstract The biotransformation of nodakenetin (NANI) by rat liver microsomes in vitro was investigated. Two major polar metabolites were produced by liver microsomes from phenobarbital-pretreated rats and detected by reversed-phase high-performance liquid chromatography (RP-HPLC) analysis. The chemical structures of two metabolites were firmly identified as 3,(R)-hydroxy-nodakenetin-3,-ol and 3,(S)-hydroxy-nodakenetin-3,-ol, respectively, on the basis of their 1H-NMR, MS and optical rotation analysis. The latter was a new compound. A sensitive, selective and simple RP-HPLC method has been developed for the simultaneous determination of NANI and its two major metabolites in rat liver microsomes. Chromatographic conditions comprise a C18 column, a mobile phase with MeOH-H2O (40 : 60, v/v), a total run time of 40 min, and ultraviolet absorbance detection at 330 nm. In the rat heat-inactivated liver microsomal supernatant, the lower limits of detection and quantification of metabolite I, metabolite II and NANI were 5.0, 2.0, 10.0 ng/mL and 20.0, 5.0, 50.0 ng/mL, respectively, and their calibration curves were linear over the concentration range 50,400, 20,120 and 150,24000 ng/mL, respectively. The results provided a firm basis for further evaluating the pharmacokinetics and clinical efficacy of NANI. Copyright © 2009 John Wiley & Sons, Ltd. [source] | ||||||||||