Roger Traub, MD and Miles Whittington, PhD
- Published in print:
- 2010
- Published Online:
- May 2010
- ISBN:
- 9780195342796
- eISBN:
- 9780199776276
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195342796.001.0001
- Subject:
- Neuroscience, Molecular and Cellular Systems, Development
This book reviews a number of clinical neuropsychiatric conditions in which brain oscillations play an essential role. It discusses how the intrinsic properties of neurons, and the interactions ...
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This book reviews a number of clinical neuropsychiatric conditions in which brain oscillations play an essential role. It discusses how the intrinsic properties of neurons, and the interactions between neurons – mediated by both chemical synapses and by gap junctions – can lead to oscillations in populations of cells. The discussion is based largely on data derived from in vitro systems (hippocampus, cerebral and cerebellar cortex) and from network modeling. Finally, the book considers how brain oscillations can provide insight into normal brain function as well as pathophysiology.Less
This book reviews a number of clinical neuropsychiatric conditions in which brain oscillations play an essential role. It discusses how the intrinsic properties of neurons, and the interactions between neurons – mediated by both chemical synapses and by gap junctions – can lead to oscillations in populations of cells. The discussion is based largely on data derived from in vitro systems (hippocampus, cerebral and cerebellar cortex) and from network modeling. Finally, the book considers how brain oscillations can provide insight into normal brain function as well as pathophysiology.
W. Otto Friesen and Jonathon A. Friesen
- Published in print:
- 2009
- Published Online:
- February 2010
- ISBN:
- 9780195371833
- eISBN:
- 9780199865178
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195371833.003.0022
- Subject:
- Psychology, Cognitive Neuroscience
The Circuit model simulates synaptic interactions among large numbers of neurons and includes many currents and derived values. This chapter gives the equations for the membrane potentials in ...
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The Circuit model simulates synaptic interactions among large numbers of neurons and includes many currents and derived values. This chapter gives the equations for the membrane potentials in circuits of three-compartment invertebrate neurons with a passive soma, a neurite, where all synaptic interactions take place, and the axon, which is the only compartment that can generate an action potential.Less
The Circuit model simulates synaptic interactions among large numbers of neurons and includes many currents and derived values. This chapter gives the equations for the membrane potentials in circuits of three-compartment invertebrate neurons with a passive soma, a neurite, where all synaptic interactions take place, and the axon, which is the only compartment that can generate an action potential.
Naomi E. Chayen, John R. Helliwell, and Edward H. Snell
- Published in print:
- 2010
- Published Online:
- May 2010
- ISBN:
- 9780199213252
- eISBN:
- 9780191707575
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199213252.003.0015
- Subject:
- Physics, Crystallography: Physics
Unusual diffraction geometries may seem a curiosity but may stimulate novel avenues of application. Not least they illustrate a diversity of diffraction‐measuring possibilities. Laue diffraction ...
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Unusual diffraction geometries may seem a curiosity but may stimulate novel avenues of application. Not least they illustrate a diversity of diffraction‐measuring possibilities. Laue diffraction including 3‐dimensional detector arrangements is described. The particular congestion of neutron Laue diffraction patterns with big crystals is highlighted. The large‐angle oscillation technique is discussed including the principle with the Ewald sphere construction and practical examples of ‘LOT’ diffraction patterns. Ultra‐fine‐phi‐slicing with perfect or near‐perfect crystals is described. Particular success has been obtained with Laue diffraction where applications to time‐resolved structural intermediates using synchrotron radiation as well as hydrogen and hydration in macromolecular structure are described.Less
Unusual diffraction geometries may seem a curiosity but may stimulate novel avenues of application. Not least they illustrate a diversity of diffraction‐measuring possibilities. Laue diffraction including 3‐dimensional detector arrangements is described. The particular congestion of neutron Laue diffraction patterns with big crystals is highlighted. The large‐angle oscillation technique is discussed including the principle with the Ewald sphere construction and practical examples of ‘LOT’ diffraction patterns. Ultra‐fine‐phi‐slicing with perfect or near‐perfect crystals is described. Particular success has been obtained with Laue diffraction where applications to time‐resolved structural intermediates using synchrotron radiation as well as hydrogen and hydration in macromolecular structure are described.
Ivan Soltesz
- Published in print:
- 2006
- Published Online:
- May 2009
- ISBN:
- 9780195177015
- eISBN:
- 9780199864713
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195177015.001.1
- Subject:
- Neuroscience, Neuroendocrine and Autonomic, Techniques
This book travels a colorful journey into the fascinatingly diverse world of interneurons, an important class of highly heterogeneous cells found in all cortical neuronal networks. Interneurons are ...
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This book travels a colorful journey into the fascinatingly diverse world of interneurons, an important class of highly heterogeneous cells found in all cortical neuronal networks. Interneurons are known to play key roles in many brain functions, from sensory processing to neuronal oscillations linked to learning and memory. This book aims to provide new insights into the striking degree of cellular diversity found in interneuronal microcircuits. The book discusses the history of research into interneuronal variability, the developmental origins of interneuronal diversity, the functional roles of heterogeneity in neuronal circuits, contemporary interneuronal classification systems, and the genetic and homeostatic mechanisms that shape the degree of cell to cell variability within interneuronal populations. It elaborates on new ideas about interneuronal diversity that rest upon recent theoretical and experimental results, with arguments touching upon evolution, animal behavior, and the mathematical theory of small world networks.Less
This book travels a colorful journey into the fascinatingly diverse world of interneurons, an important class of highly heterogeneous cells found in all cortical neuronal networks. Interneurons are known to play key roles in many brain functions, from sensory processing to neuronal oscillations linked to learning and memory. This book aims to provide new insights into the striking degree of cellular diversity found in interneuronal microcircuits. The book discusses the history of research into interneuronal variability, the developmental origins of interneuronal diversity, the functional roles of heterogeneity in neuronal circuits, contemporary interneuronal classification systems, and the genetic and homeostatic mechanisms that shape the degree of cell to cell variability within interneuronal populations. It elaborates on new ideas about interneuronal diversity that rest upon recent theoretical and experimental results, with arguments touching upon evolution, animal behavior, and the mathematical theory of small world networks.
Sergey Ganichev and Willi Prettl
- Published in print:
- 2005
- Published Online:
- September 2007
- ISBN:
- 9780198528302
- eISBN:
- 9780191713637
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198528302.001.0001
- Subject:
- Physics, Condensed Matter Physics / Materials
This book presents high-power terahertz applications to semiconductors and semiconductor structures. It aims to bridge the gap between optics and microwave physics. It focuses on a core topic of ...
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This book presents high-power terahertz applications to semiconductors and semiconductor structures. It aims to bridge the gap between optics and microwave physics. It focuses on a core topic of semiconductor physics, providing a full description of the state of art of the field. The book introduces new physical phenomena which occur in the terahertz frequency range at the transition from semi-classical physics with a classical field amplitude to the fully quantized limit with photons. It covers tunneling in high-frequency fields, nonlinear absorption of radiation and radiation heating, nonlinear optics in the classical sense, Bloch-oscillations and ponderomotive forces of the terahertz radiation on free carriers, photon drag and photogalvanic effects, and terahertz spin dependent phenomena being of importance in the field of spintronics. Background information for future work and references of current literature are given. The book also discusses various experimental aspects like the generation of high-power coherent terahertz radiation, properties of materials with respect to their application in optical components, and detection schemes of short intense terahertz pulses.Less
This book presents high-power terahertz applications to semiconductors and semiconductor structures. It aims to bridge the gap between optics and microwave physics. It focuses on a core topic of semiconductor physics, providing a full description of the state of art of the field. The book introduces new physical phenomena which occur in the terahertz frequency range at the transition from semi-classical physics with a classical field amplitude to the fully quantized limit with photons. It covers tunneling in high-frequency fields, nonlinear absorption of radiation and radiation heating, nonlinear optics in the classical sense, Bloch-oscillations and ponderomotive forces of the terahertz radiation on free carriers, photon drag and photogalvanic effects, and terahertz spin dependent phenomena being of importance in the field of spintronics. Background information for future work and references of current literature are given. The book also discusses various experimental aspects like the generation of high-power coherent terahertz radiation, properties of materials with respect to their application in optical components, and detection schemes of short intense terahertz pulses.
David N. Thomas, G.E. (Tony) Fogg, Peter Convey, Christian H. Fritsen, Josep-Maria Gili, Rolf Gradinger, Johanna Laybourn-Parry, Keith Reid, and David W.H. Walton
- Published in print:
- 2008
- Published Online:
- May 2008
- ISBN:
- 9780199298112
- eISBN:
- 9780191711640
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199298112.003.0001
- Subject:
- Biology, Ecology
This chapter begins with a brief description of the physical characteristics of polar regions, specifically in the Arctic and Antarctic. It then discusses the energy balances of the polar regions, ...
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This chapter begins with a brief description of the physical characteristics of polar regions, specifically in the Arctic and Antarctic. It then discusses the energy balances of the polar regions, climate, thermohaline circulation, El Niño Southern Oscillation, Arctic and North Atlantic Oscillations, and magnetic and electrical phenomena.Less
This chapter begins with a brief description of the physical characteristics of polar regions, specifically in the Arctic and Antarctic. It then discusses the energy balances of the polar regions, climate, thermohaline circulation, El Niño Southern Oscillation, Arctic and North Atlantic Oscillations, and magnetic and electrical phenomena.
Patrick Lehodey
- Published in print:
- 2005
- Published Online:
- September 2007
- ISBN:
- 9780198507499
- eISBN:
- 9780191709845
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198507499.003.0011
- Subject:
- Biology, Aquatic Biology
This chapter presents a brief description of the climate oscillations in the Pacific Ocean and their biological consequences. It then provides another illustration of the connection between climate ...
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This chapter presents a brief description of the climate oscillations in the Pacific Ocean and their biological consequences. It then provides another illustration of the connection between climate and fisheries using the example of tuna species in the Pacific Ocean. A modeling approach is also presented and used to explore the underlying mechanisms linking changes in climate and tuna populations.Less
This chapter presents a brief description of the climate oscillations in the Pacific Ocean and their biological consequences. It then provides another illustration of the connection between climate and fisheries using the example of tuna species in the Pacific Ocean. A modeling approach is also presented and used to explore the underlying mechanisms linking changes in climate and tuna populations.
Michael D. McDonald and Ian Budge
- Published in print:
- 2005
- Published Online:
- February 2006
- ISBN:
- 9780199286720
- eISBN:
- 9780191603327
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/0199286728.003.0010
- Subject:
- Political Science, Comparative Politics
Policy outcomes are rather stable while politics in the short-term are in a state of flux — one which oscillates round long-term equilibrium point which is fairly stable within each country. Such ...
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Policy outcomes are rather stable while politics in the short-term are in a state of flux — one which oscillates round long-term equilibrium point which is fairly stable within each country. Such well-established policy positions distinguish long-term policy regimes within each country. To change these, governments need popular support over fairly long periods of time, which usually is not forthcoming. Typically, actual policy outputs oscillate round a long-term equilibrium, which does not change very much over a four or five election period.Less
Policy outcomes are rather stable while politics in the short-term are in a state of flux — one which oscillates round long-term equilibrium point which is fairly stable within each country. Such well-established policy positions distinguish long-term policy regimes within each country. To change these, governments need popular support over fairly long periods of time, which usually is not forthcoming. Typically, actual policy outputs oscillate round a long-term equilibrium, which does not change very much over a four or five election period.
Eduard Feireisl
- Published in print:
- 2003
- Published Online:
- September 2007
- ISBN:
- 9780198528388
- eISBN:
- 9780191713590
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198528388.003.0006
- Subject:
- Mathematics, Applied Mathematics
Given the rather poor a priori estimates available, the methods of weak convergence play a decisive role in the mathematical theory to be developed in this book. Both ‘classical’ problems of this ...
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Given the rather poor a priori estimates available, the methods of weak convergence play a decisive role in the mathematical theory to be developed in this book. Both ‘classical’ problems of this approach — the presence of oscillations and concentrations in sequences of approximate solutions — are present. The well-known results of the theory of compensated compactness are used in order to cope with possible density oscillations. More specifically, the fundamental properties of the effective viscous pressure discovered by P.-L. Lions are discussed together with an alternative proof of ‘continuity’ of this quantity via the famous div-curl lemma. Next, the concept of oscillation defect measure is introduced, and its relation to the propagation of oscillations and the renormalized continuity equation is established. Furthermore, the whole machinery is applied to the problem of propagation of density oscillations in a sequence of solutions, and it is shown that the oscillations decay in time at a uniform rate independent of the choice of initial data provided the pressure is a monotone function of the density. The weak sequential stability (compactness) of the set of weak solutions is established for optimal values of the ‘adiabatic’ exponent. In particular, the physically interesting case of the monoatomic gas in the isentropic regime in three space dimensions can be treated — a problem left open in current theory. Possible concentrations in the temperature are treated via the method of renormalization (rescaling). A ‘renormalized’ formulation of the thermal energy equation is supplemented with the concept of a renormalized limit, usefulness of which being demonstrated on the problem of weak sequential stability and the study of possible concentrations of the temperature in the thermal energy equation.Less
Given the rather poor a priori estimates available, the methods of weak convergence play a decisive role in the mathematical theory to be developed in this book. Both ‘classical’ problems of this approach — the presence of oscillations and concentrations in sequences of approximate solutions — are present. The well-known results of the theory of compensated compactness are used in order to cope with possible density oscillations. More specifically, the fundamental properties of the effective viscous pressure discovered by P.-L. Lions are discussed together with an alternative proof of ‘continuity’ of this quantity via the famous div-curl lemma. Next, the concept of oscillation defect measure is introduced, and its relation to the propagation of oscillations and the renormalized continuity equation is established. Furthermore, the whole machinery is applied to the problem of propagation of density oscillations in a sequence of solutions, and it is shown that the oscillations decay in time at a uniform rate independent of the choice of initial data provided the pressure is a monotone function of the density. The weak sequential stability (compactness) of the set of weak solutions is established for optimal values of the ‘adiabatic’ exponent. In particular, the physically interesting case of the monoatomic gas in the isentropic regime in three space dimensions can be treated — a problem left open in current theory. Possible concentrations in the temperature are treated via the method of renormalization (rescaling). A ‘renormalized’ formulation of the thermal energy equation is supplemented with the concept of a renormalized limit, usefulness of which being demonstrated on the problem of weak sequential stability and the study of possible concentrations of the temperature in the thermal energy equation.
Jacob Hagberg, Björn G. Tunberg, Gunther Wieking, Ingrid Kröncke, and Andrea Belgrano
- Published in print:
- 2005
- Published Online:
- September 2007
- ISBN:
- 9780198507499
- eISBN:
- 9780191709845
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198507499.003.0009
- Subject:
- Biology, Aquatic Biology
Climatic variability is most likely to have an effect on marine populations and it is important to understand further the synchronicity between climatic oscillations and the life cycle of benthic ...
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Climatic variability is most likely to have an effect on marine populations and it is important to understand further the synchronicity between climatic oscillations and the life cycle of benthic species. This chapter presents a variety of studies on climate influence on marine benthos communities in the North Sea, Skagerrak, and Baltic. The main conclusion is that the NAO affects single species as well as whole communities and functional groups, and that the impact may differ geographically and depend on the species composition of the communities.Less
Climatic variability is most likely to have an effect on marine populations and it is important to understand further the synchronicity between climatic oscillations and the life cycle of benthic species. This chapter presents a variety of studies on climate influence on marine benthos communities in the North Sea, Skagerrak, and Baltic. The main conclusion is that the NAO affects single species as well as whole communities and functional groups, and that the impact may differ geographically and depend on the species composition of the communities.
Thomas Ihn
- Published in print:
- 2009
- Published Online:
- February 2010
- ISBN:
- 9780199534425
- eISBN:
- 9780191715297
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199534425.003.0017
- Subject:
- Physics, Condensed Matter Physics / Materials
This chapter continues the discussion of interaction effects in transport starts from the fractional quantum Hall effect in Chapter 16, but returns to the case of zero magnetic field. The influence ...
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This chapter continues the discussion of interaction effects in transport starts from the fractional quantum Hall effect in Chapter 16, but returns to the case of zero magnetic field. The influence of screening on the Drude conductivity and its temperature dependence are elucidated. Interaction-related quantum corrections to the Drude conductivity are discussed in the picture of multiple scattering at Friedel oscillations.Less
This chapter continues the discussion of interaction effects in transport starts from the fractional quantum Hall effect in Chapter 16, but returns to the case of zero magnetic field. The influence of screening on the Drude conductivity and its temperature dependence are elucidated. Interaction-related quantum corrections to the Drude conductivity are discussed in the picture of multiple scattering at Friedel oscillations.
Roger D. Roger and Miles A. Whittington
- Published in print:
- 2010
- Published Online:
- May 2010
- ISBN:
- 9780195342796
- eISBN:
- 9780199776276
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195342796.003.0001
- Subject:
- Neuroscience, Molecular and Cellular Systems, Development
In a previous monograph, the authors described an experimental model of the 40 Hz oscillations produced in vivo by visual stimulation. The model involved tetanic stimulation of one or two sites in a ...
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In a previous monograph, the authors described an experimental model of the 40 Hz oscillations produced in vivo by visual stimulation. The model involved tetanic stimulation of one or two sites in a hippocampal slice, and was able to produce synchronized oscillations in the presence of axonal conduction delays. The monograph showed how network simulations and in vitro studies complement each other, for example in elucidating the cellular mechanisms by such long-range synchrony could occur. The present monograph continues this type of research, but focuses on additional sorts of oscillations, many of which depend on gap junctions.Less
In a previous monograph, the authors described an experimental model of the 40 Hz oscillations produced in vivo by visual stimulation. The model involved tetanic stimulation of one or two sites in a hippocampal slice, and was able to produce synchronized oscillations in the presence of axonal conduction delays. The monograph showed how network simulations and in vitro studies complement each other, for example in elucidating the cellular mechanisms by such long-range synchrony could occur. The present monograph continues this type of research, but focuses on additional sorts of oscillations, many of which depend on gap junctions.
Roger D. Roger and Miles A. Whittington
- Published in print:
- 2010
- Published Online:
- May 2010
- ISBN:
- 9780195342796
- eISBN:
- 9780199776276
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195342796.003.0004
- Subject:
- Neuroscience, Molecular and Cellular Systems, Development
Epilepsy can be viewed from inter-related clinical and electrical/cellular points of view. Before and during a so-called electrographic seizure, neuronal events become both highly correlated ...
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Epilepsy can be viewed from inter-related clinical and electrical/cellular points of view. Before and during a so-called electrographic seizure, neuronal events become both highly correlated (synchronized) and also organized in time. The latter organization occurs over a wide range of frequencies. Prior to seizures, very fast oscillations (VFO, >70-80 Hz) occur, that are dependent on gap junctions. Understanding how VFO is generated may provide a therapeutic target.Less
Epilepsy can be viewed from inter-related clinical and electrical/cellular points of view. Before and during a so-called electrographic seizure, neuronal events become both highly correlated (synchronized) and also organized in time. The latter organization occurs over a wide range of frequencies. Prior to seizures, very fast oscillations (VFO, >70-80 Hz) occur, that are dependent on gap junctions. Understanding how VFO is generated may provide a therapeutic target.
Roger D. Roger and Miles A. Whittington
- Published in print:
- 2010
- Published Online:
- May 2010
- ISBN:
- 9780195342796
- eISBN:
- 9780199776276
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195342796.003.0005
- Subject:
- Neuroscience, Molecular and Cellular Systems, Development
Parkinson's Disease is associated with loss of brainstem dopaminergic neurons, and loss of dopaminergic innervation of basal ganglia and cortex. The most disabling clinical symptoms are slowness of ...
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Parkinson's Disease is associated with loss of brainstem dopaminergic neurons, and loss of dopaminergic innervation of basal ganglia and cortex. The most disabling clinical symptoms are slowness of movement and postural instability. Both in the clinical disorder, and in experimental models, dopaminergic deprivation leads to enhanced beta oscillations (~20 – 30 Hz) in motor and motor-related regions. Interestingly, beta oscillations occuring during cognitive tasks are associated with immobility. Beta oscillations can also be induced in vitro (Chapter 11).Less
Parkinson's Disease is associated with loss of brainstem dopaminergic neurons, and loss of dopaminergic innervation of basal ganglia and cortex. The most disabling clinical symptoms are slowness of movement and postural instability. Both in the clinical disorder, and in experimental models, dopaminergic deprivation leads to enhanced beta oscillations (~20 – 30 Hz) in motor and motor-related regions. Interestingly, beta oscillations occuring during cognitive tasks are associated with immobility. Beta oscillations can also be induced in vitro (Chapter 11).
Dietmar Straile
- Published in print:
- 2005
- Published Online:
- September 2007
- ISBN:
- 9780198507499
- eISBN:
- 9780191709845
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198507499.003.0013
- Subject:
- Biology, Aquatic Biology
North Atlantic climate variability not only influences North Atlantic ecosystems, but also influences terrestrial and freshwater ecosystems across the Northern Hemisphere. This chapter discusses ...
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North Atlantic climate variability not only influences North Atlantic ecosystems, but also influences terrestrial and freshwater ecosystems across the Northern Hemisphere. This chapter discusses selected aspects of NAO impacts on freshwater ecosystems, which might shed some light or pose new questions on the NAO impacts on the North Atlantic. Fluctuations originating with the NAO affect hydrology as well as phytoplankton and zooplankton biology. Effects include timing of phytoplankton blooms, balance between abundance of diatoms and other phytoplankton species, and population dynamics of Daphnia.Less
North Atlantic climate variability not only influences North Atlantic ecosystems, but also influences terrestrial and freshwater ecosystems across the Northern Hemisphere. This chapter discusses selected aspects of NAO impacts on freshwater ecosystems, which might shed some light or pose new questions on the NAO impacts on the North Atlantic. Fluctuations originating with the NAO affect hydrology as well as phytoplankton and zooplankton biology. Effects include timing of phytoplankton blooms, balance between abundance of diatoms and other phytoplankton species, and population dynamics of Daphnia.
Mauricio Lima and Fabian M. Jaksic
- Published in print:
- 2005
- Published Online:
- September 2007
- ISBN:
- 9780198507499
- eISBN:
- 9780191709845
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198507499.003.0016
- Subject:
- Biology, Aquatic Biology
This chapter aims to cast new light upon the preceding chapters, drawing upon the authors' experience along the western fringe of South America, especially on data gained from Chilean ecosystems. The ...
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This chapter aims to cast new light upon the preceding chapters, drawing upon the authors' experience along the western fringe of South America, especially on data gained from Chilean ecosystems. The eastern side of the tropical Pacific — where El Niño-Southern Oscillation (ENSO) plays a highly significant role — is linked closely to the NAO impacts in the North Atlantic sector. Specifically, the impacts on plants, invertebrates, amphibians, birds, and mammals are considered.Less
This chapter aims to cast new light upon the preceding chapters, drawing upon the authors' experience along the western fringe of South America, especially on data gained from Chilean ecosystems. The eastern side of the tropical Pacific — where El Niño-Southern Oscillation (ENSO) plays a highly significant role — is linked closely to the NAO impacts in the North Atlantic sector. Specifically, the impacts on plants, invertebrates, amphibians, birds, and mammals are considered.
Roger D. Roger and Miles A. Whittington
- Published in print:
- 2010
- Published Online:
- May 2010
- ISBN:
- 9780195342796
- eISBN:
- 9780199776276
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195342796.003.0010
- Subject:
- Neuroscience, Molecular and Cellular Systems, Development
VFO occurs in in vitro models when chemical receptors are blocked. In particular, VFO does not require GABAA receptors, even though interneurons fire at high rates during in vivo very fast ...
More
VFO occurs in in vitro models when chemical receptors are blocked. In particular, VFO does not require GABAA receptors, even though interneurons fire at high rates during in vivo very fast oscillations. VFO can be accounted for by a model in which neuronal spiking percolates through a sparse network of electrically coupled axons. This model predicts that VFO frequency depends on gap junction conductance, mediated by an effect on crossing time (i.e. the time it takes for a spike in one axon to elicit a spike in a coupled axon, estimated to be of order 0.2 ms). VFO in cerebellar slices also depends on gap junctions, but the physical principles are slightly different: cerebellar VFO appears to depend on many:one propagation of spiking, in effect a form of axonal coincidence detection.Less
VFO occurs in in vitro models when chemical receptors are blocked. In particular, VFO does not require GABAA receptors, even though interneurons fire at high rates during in vivo very fast oscillations. VFO can be accounted for by a model in which neuronal spiking percolates through a sparse network of electrically coupled axons. This model predicts that VFO frequency depends on gap junction conductance, mediated by an effect on crossing time (i.e. the time it takes for a spike in one axon to elicit a spike in a coupled axon, estimated to be of order 0.2 ms). VFO in cerebellar slices also depends on gap junctions, but the physical principles are slightly different: cerebellar VFO appears to depend on many:one propagation of spiking, in effect a form of axonal coincidence detection.
Michael Graham, Ben Halpern, and Mark Carr
- Published in print:
- 2008
- Published Online:
- May 2008
- ISBN:
- 9780195319958
- eISBN:
- 9780199869596
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195319958.003.0005
- Subject:
- Biology, Aquatic Biology
The chapter describes the geology, oceanography, and patterns of biogeography of the California kelp forests. The structure and biodiversity of the kelp forest food web for all trophic guilds is ...
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The chapter describes the geology, oceanography, and patterns of biogeography of the California kelp forests. The structure and biodiversity of the kelp forest food web for all trophic guilds is described as well as findings from experimental manipulations and long time series studies. The chapter finishes with a discussion of the role of fishing, habitat loss, and climate change on these kelp forests.Less
The chapter describes the geology, oceanography, and patterns of biogeography of the California kelp forests. The structure and biodiversity of the kelp forest food web for all trophic guilds is described as well as findings from experimental manipulations and long time series studies. The chapter finishes with a discussion of the role of fishing, habitat loss, and climate change on these kelp forests.
Buzsáki György
- Published in print:
- 2006
- Published Online:
- May 2009
- ISBN:
- 9780195301069
- eISBN:
- 9780199863716
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195301069.003.0007
- Subject:
- Neuroscience, Neuroendocrine and Autonomic, Techniques
In the absence of environmental inputs, such as during sleep, the brain engages in self-organized activity. The isolated neocortex, or small pieces of it, can sustain self-organized patterns. Neurons ...
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In the absence of environmental inputs, such as during sleep, the brain engages in self-organized activity. The isolated neocortex, or small pieces of it, can sustain self-organized patterns. Neurons in local or global regions of the cerebral cortex swing between excitable and less excitable (up and down) states. In the intact brain, properly timed exogenous influences can trigger upswing changes, if the cortical network has already spent a sufficient amount of time in the down state. Parallel with the increasing probability of cortical up-down state shifts, the membrane potential of thalamocortical neurons progressively polarizes. Cholinergic activity during REM sleep and in the waking brain is mainly responsible for the lack of down states in cortical neurons. The most prominent oscillation of the waking brain is the family of alpha rhythms that occur selectively in every sensory and motor thalamocortical system in the absence of sensory inputs.Less
In the absence of environmental inputs, such as during sleep, the brain engages in self-organized activity. The isolated neocortex, or small pieces of it, can sustain self-organized patterns. Neurons in local or global regions of the cerebral cortex swing between excitable and less excitable (up and down) states. In the intact brain, properly timed exogenous influences can trigger upswing changes, if the cortical network has already spent a sufficient amount of time in the down state. Parallel with the increasing probability of cortical up-down state shifts, the membrane potential of thalamocortical neurons progressively polarizes. Cholinergic activity during REM sleep and in the waking brain is mainly responsible for the lack of down states in cortical neurons. The most prominent oscillation of the waking brain is the family of alpha rhythms that occur selectively in every sensory and motor thalamocortical system in the absence of sensory inputs.
Alexey V. Kavokin and Jeremy J. Baumberg
- Published in print:
- 2007
- Published Online:
- May 2008
- ISBN:
- 9780199228942
- eISBN:
- 9780191711190
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199228942.003.0005
- Subject:
- Physics, Atomic, Laser, and Optical Physics
This chapter starts from description of Rabi and Bloch-oscillations in semiconductors. It introduces the exciton-light coupling Hamiltonian in terms of the secondary quantization theory, and ...
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This chapter starts from description of Rabi and Bloch-oscillations in semiconductors. It introduces the exciton-light coupling Hamiltonian in terms of the secondary quantization theory, and considers different approaches to quantum description of light-matter coupling, including the Jaynes-Cummings model and the Dicke model. The crossover from bosonic to fermionic statistics for excitons is then discussed. Finally, the dispersion of exciton-polaritons in microcavities is obtained and the polariton Hamiltonian is constructed.Less
This chapter starts from description of Rabi and Bloch-oscillations in semiconductors. It introduces the exciton-light coupling Hamiltonian in terms of the secondary quantization theory, and considers different approaches to quantum description of light-matter coupling, including the Jaynes-Cummings model and the Dicke model. The crossover from bosonic to fermionic statistics for excitons is then discussed. Finally, the dispersion of exciton-polaritons in microcavities is obtained and the polariton Hamiltonian is constructed.
