27 research outputs found

    The Source of Spontaneous Activity in the Main Olfactory Bulb of the Rat

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    In vivo, most neurons in the main olfactory bulb exhibit robust spontaneous activity. This paper tests the hypothesis that spontaneous activity in olfactory receptor neurons drives much of the spontaneous activity in mitral and tufted cells via excitatory synapses.Single units were recorded in vivo from the main olfactory bulb of a rat before, during, and after application of lidocaine to the olfactory nerve. The effect of lidocaine on the conduction of action potentials from the olfactory epithelium to the olfactory bulb was assessed by electrically stimulating the olfactory nerve rostral to the application site and monitoring the field potential evoked in the bulb.Lidocaine caused a significant decrease in the amplitude of the olfactory nerve evoked field potential that was recorded in the olfactory bulb. By contrast, the lidocaine block did not significantly alter the spontaneous activity of single units in the bulb, nor did it alter the field potential evoked by electrical stimulation of the lateral olfactory tract. Lidocaine block also did not change the temporal patters of action potential or their synchronization with respiration.Spontaneous activity in neurons of the main olfactory bulb is not driven mainly by activity in olfactory receptor neurons despite the extensive convergence onto mitral and tufted cells. These results suggest that spontaneous activity of mitral and tufted is either an inherent property of these cells or is driven by centrifugal inputs to the bulb

    "It's what midwifery is all about": Western Australian midwives' experiences of being 'with woman' during labour and birth in the known midwife model

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    Background: The phenomenon of being 'with woman' is fundamental to midwifery as it underpins its philosophy, relationships and practices. There is an identified gap in knowledge around the 'with woman' phenomenon from the perspective of midwives providing care in a variety of contexts. As such, the aim of this study was to explore the experiences of being 'with woman' during labour and birth from the perspective of midwives' working in a model where care is provided by a known midwife. Methods: A descriptive phenomenological design was employed with ten midwives working in a 'known midwife' model who described their experiences of being 'with woman' during labour and birth. The method was informed by Husserlian philosophy which seeks to explore the same phenomenon through rich descriptions by individuals revealing commonalities of the experience. Results: Five themes emerged 1) Building relationships; 2) Woman centred care; 3) Impact on the midwife; 4) Impact on the woman; and 5) Challenges in the Known Midwife model. Midwives emphasised the importance of trusting relationships while being 'with woman', confirming that this relationship extends beyond the woman - midwife relationship to include the woman's support people and family. Being 'with woman' during labour and birth in the context of the relationship facilitates woman-centred care. Being 'with woman' influences midwives, and, it is noted, the women that midwives are working with. Finally, challenges that impact being 'with woman' in the known midwife model are shared by midwives. Conclusions: Findings offer valuable insight into midwives' experiences of being 'with woman' in the context of models that provide care by a known midwife. In this model, the trusting relationship is the conduit for being 'with woman' which influences the midwife, the profession of midwifery, as well as women and their families. Descriptions of challenges to being 'with woman' provide opportunities for professional development and service review. Rich descriptions from the unique voice of midwives, provided insight into the applied practices of being 'with woman' in a known midwife model which adds important knowledge concerning a phenomenon so deeply embedded in the philosophy and practices of the profession of midwifery

    Lacunarity, lexicography and beyond: integration of the introduction of a linguo-cultural concept and the development of L2 learners’ dictionary skills

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    The paper discusses the integration of presenting theoretical linguocultural knowledge and developing dictionary skills in advanced students of a foreign language. The proposed approach allows showing students the interdisciplinary character of various issues, one of which is cross-linguistic lacunarity. It is given as an example of a phenomenon, whose introduction can be combined with the development of students’ dictionary use abilities. Lacunarity consists in the lack of some source language elements in the target language. Two main kinds of lacunae are distinguished: linguistic and referential ones. The focal issue of the paper is how the information on the lacunary character of words can be presented to advanced students of English as a foreign language, in this paper Polish learners, so that they could consider the phenomenon in terms of bilingual lexicography: first, becoming aware of the specifics of their description; second, practising their dictionary skills by analysing entries for selected lacunary lexical and phraseological units; third, combining the information and skills in doing creative tasks, related to lacunarity and its bilingual lexicographic descriptions. Furthermore, additional activities are proposed for revising the acquired knowledge on lacunarity and advancing dictionary use. Offering students tasks, which require them to adopt a different perspective, aims to increase their involvement in the learning process and to foster their autonomy as learners. Encouraging learners to reflect on lacunae and their lexicographic description is expected to familiarize them with the phenomenon and simultaneously to develop their dictionary skills by doing especially designed [email protected] University of Bialystok101-11

    Mitochondrial physiology

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    As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

    Mitochondrial physiology

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    As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

    Research and Science Today No. 2(4)/2012

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    The effects of olfactory nerve block on mean rate.

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    <p>The mean change in the amplitude of the ON-evoked field potential (A) caused by lidocaine application is compared to the mean change in the rate of spontaneous activity (B).</p

    The effects of olfactory nerve block on field potentials.

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    <p>Field potentials recorded in the main olfactory bulb were evoked by stimulating the olfactory nerve (ON field potential, A and B) and the lateral olfactory tract (LOT field potential, C and D) before (control, A and C) and after (ON block, B and D) applying lidocaine to the olfactory nerve.</p
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