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Precise Manner (precise + manner)
Selected AbstractsBison breeding characteristics and interpretation of archaeological seasonality revisitedINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 6 2006D. WaldeArticle first published online: 17 JUL 200 Abstract Bison breeding behaviour has been used for the last three decades as the basis for developing methods for assigning season-of-occupation estimates to archaeological sites on the North American Plains. These methods are based upon the supposition that the North American bison breeding season is extremely short and that genetically controlled ontological characteristics such as foetal growth and tooth eruption sequences can therefore be used to infer site seasonality in a reasonably straightforward and precise manner. This paper reviews bison population studies conducted during the past 30 years to reassess present understandings of the length of North American bison breeding seasons. It is concluded that the bison breeding season regularly extends over a period of three to four months, and that initiation of ontological development will therefore also vary over the same period of time. Bison development characteristics cannot provide a reliable or precise means of assigning seasonality to archaeological sites on the North American Plains. It is suggested that methods using physical characteristics such as dental cementum incrementation which are directly affected by seasonal changes could be more productive. Copyright © 2006 John Wiley & Sons, Ltd. [source] Challenging the Bioethical Application of the Autonomy Principle within Multicultural SocietiesJOURNAL OF APPLIED PHILOSOPHY, Issue 1 2004Andrew Fagan abstract,This article critically re-examines the application of the principle of patient autonomy within bioethics. In complex societies such as those found in North America and Europe health care professionals are increasingly confronted by patients from diverse ethnic, cultural, and religious backgrounds. This affects the relationship between clinicians and patients to the extent that patients' deliberations upon the proposed courses of treatment can, in various ways and to varying extents, be influenced by their ethnic, cultural, and religious commitments. The principle of patient autonomy is the main normative constraint imposed upon medical treatment. Bioethicists typically appeal to the principle of patient autonomy as a means for generally attempting to resolve conflict between patients and clinicians. In recent years a number of bioethicists have responded to the condition of multiculturalism by arguing that the autonomy principle provides the basis for a common moral discourse capable of regulating the relationship between clinicians and patients in those situations where patients' beliefs and commitments do or may contradict the ethos of biomedicine. This article challenges that claim. I argue that the precise manner in which the autonomy principle is philosophically formulated within such accounts prohibits bioethicists' deployment of autonomy as a core ideal for a common moral discourse within multicultural societies. The formulation of autonomy underlying such accounts cannot be extended to simply assimilate individuals' most fundamental religious and cultural commitments and affiliations per se. I challenge the assumption that respecting prospective patients' fundamental religious and cultural commitments is necessarily always compatible with respecting their autonomy. I argue that the character of some peoples' relationship with their cultural or religious community acts to significantly constrain the possibilities for acting autonomously. The implication is clear. The autonomy principle may be presently invalidly applied in certain circumstances because the conditions for the exercise of autonomy have not been fully or even adequately satisfied. This is a controversial claim. The precise terms of my argument, while addressing the specific application of the autonomy principle within bioethics, will resonate beyond this sphere and raises questions for attempts to establish a common moral discourse upon the ideal of personal autonomy within multicultural societies generally. [source] Optimization of pathogenicity assays to study the Arabidopsis thaliana,Xanthomonas campestris pv. campestris pathosystemMOLECULAR PLANT PATHOLOGY, Issue 3 2005DAMIEN MEYER SUMMARY The cruciferous weed Arabidopsis thaliana and the causal agent of black rot disease of Crucifers Xanthomonas campestris pv. campestris (Xcc) are both model organisms in plant pathology. Their interaction has been studied successfully in the past, but these investigations suffered from high variability. In the present study, we describe an improved Arabidopsis,Xcc pathosystem that is based on a wound inoculation procedure. We show that after wound inoculation, Xcc colonizes the vascular system of Arabidopsis leaves and causes typical black rot symptoms in a compatible interaction, while in an incompatible interaction bacterial multiplication is inhibited. The highly synchronous and reproducible symptom expression allowed the development of a disease scoring scheme that enabled us to analyse the effects of mutations in individual genes on plant resistance or on bacterial virulence in a simple and precise manner. This optimized Arabidopsis,Xcc pathosystem will be a robust tool for further genetic and post-genomic investigation of fundamental questions in plant pathology. [source] Efficient Ca2+ buffering in fast-spiking basket cells of rat hippocampusTHE JOURNAL OF PHYSIOLOGY, Issue 8 2008Yexica Aponte Fast-spiking parvalbumin-expressing basket cells (BCs) represent a major type of inhibitory interneuron in the hippocampus. These cells inhibit principal cells in a temporally precise manner and are involved in the generation of network oscillations. Although BCs show a unique expression profile of Ca2+ -permeable receptors, Ca2+ -binding proteins and Ca2+ -dependent signalling molecules, physiological Ca2+ signalling in these interneurons has not been investigated. To study action potential (AP)-induced dendritic Ca2+ influx and buffering, we combined whole-cell patch-clamp recordings with ratiometric Ca2+ imaging from the proximal apical dendrites of rigorously identified BCs in acute slices, using the high-affinity Ca2+ indicator fura-2 or the low-affinity dye fura-FF. Single APs evoked dendritic Ca2+ transients with small amplitude. Bursts of APs evoked Ca2+ transients with amplitudes that increased linearly with AP number. Analysis of Ca2+ transients under steady-state conditions with different fura-2 concentrations and during loading with 200 ,m fura-2 indicated that the endogenous Ca2+ -binding ratio was ,200 (,S= 202 ± 26 for the loading experiments). The peak amplitude of the Ca2+ transients measured directly with 100 ,m fura-FF was 39 nm AP,1. At ,23°C, the decay time constant of the Ca2+ transients was 390 ms, corresponding to an extrusion rate of ,600 s,1. At 34°C, the decay time constant was 203 ms and the corresponding extrusion rate was ,1100 s,1. At both temperatures, continuous theta-burst activity with three to five APs per theta cycle, as occurs in vivo during exploration, led to a moderate increase in the global Ca2+ concentration that was proportional to AP number, whereas more intense stimulation was required to reach micromolar Ca2+ concentrations and to shift Ca2+ signalling into a non-linear regime. In conclusion, dentate gyrus BCs show a high endogenous Ca2+ -binding ratio, a small AP-induced dendritic Ca2+ influx, and a relatively slow Ca2+ extrusion. These specific buffering properties of BCs will sharpen the time course of local Ca2+ signals, while prolonging the decay of global Ca2+ signals. [source] Application of Laser-Assisted Microdissection for Gene Expression Analysis of Mammalian Germ CellsANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 3 2010R. Kenngott With 1 figure and 2 tables Summary Laser-assisted microdissection (LAM) is an important method to provide new significant insights into many embryological processes. To understand these processes, it is important to obtain specific populations of cells from complex tissue in an efficient and precise manner and to combine with many different molecular biological methods. During the last few years, the sophistication of the techniques of LAM has increased significantly and made the procedure easy to use. New micro-extraction protocols for DNA, RNA and proteins now allow broad downstream applications in the fields of genomics, transcriptomics and proteomics. In this review, we give a short overview of the application of LAM in combination with quantitative qPCR for the analysis of gene expression in mammalian germ cells. 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