C. Mathew Mate
- Published in print:
- 2007
- Published Online:
- January 2008
- ISBN:
- 9780198526780
- eISBN:
- 9780191712098
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198526780.001.0001
- Subject:
- Physics, Condensed Matter Physics / Materials
Friction, lubrication, adhesion, and wear are prevalent physical phenomena in everyday life and in many key technologies. This book incorporates a bottom-up approach to friction, lubrication, and ...
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Friction, lubrication, adhesion, and wear are prevalent physical phenomena in everyday life and in many key technologies. This book incorporates a bottom-up approach to friction, lubrication, and wear. This is done by focusing on how these tribological phenomena occur on the small scale — the atomic to the micrometer scale — a field often called nanotribology. The book covers the microscopic origins of the common tribological concepts of roughness, elasticity, plasticity, friction coefficients, and wear coefficients. Some macroscale concepts (like elasticity) scale down well to the micro- and atomic-scale, while other macroscale concepts (like hydrodynamic lubrication) do not. In addition, this book also has chapters on topics not typically found in tribology texts: surface energy, surface forces, lubrication in confined spaces, and the atomistic origins of friction. These chapters cover tribological concepts that have become increasingly important at the small scale: capillary condensation, disjoining pressure, contact electrification, molecular slippage at interfaces, and atomic scale stick-slip. Numerous examples are provided throughout the book on how a nanoscale understanding of tribological phenomena is essential to the proper engineering of important new technologies such as MEMS, disk drives, and nanoimprinting.Less
Friction, lubrication, adhesion, and wear are prevalent physical phenomena in everyday life and in many key technologies. This book incorporates a bottom-up approach to friction, lubrication, and wear. This is done by focusing on how these tribological phenomena occur on the small scale — the atomic to the micrometer scale — a field often called nanotribology. The book covers the microscopic origins of the common tribological concepts of roughness, elasticity, plasticity, friction coefficients, and wear coefficients. Some macroscale concepts (like elasticity) scale down well to the micro- and atomic-scale, while other macroscale concepts (like hydrodynamic lubrication) do not. In addition, this book also has chapters on topics not typically found in tribology texts: surface energy, surface forces, lubrication in confined spaces, and the atomistic origins of friction. These chapters cover tribological concepts that have become increasingly important at the small scale: capillary condensation, disjoining pressure, contact electrification, molecular slippage at interfaces, and atomic scale stick-slip. Numerous examples are provided throughout the book on how a nanoscale understanding of tribological phenomena is essential to the proper engineering of important new technologies such as MEMS, disk drives, and nanoimprinting.
Nikolas Rose and Joelle M. Abi-Rached
- Published in print:
- 2013
- Published Online:
- October 2017
- ISBN:
- 9780691149608
- eISBN:
- 9781400846337
- Item type:
- chapter
- Publisher:
- Princeton University Press
- DOI:
- 10.23943/princeton/9780691149608.003.0002
- Subject:
- Neuroscience, Development
This chapter examines the neuromolecular and plastic brain. Ideas about plasticity and the openness of brains to environment influences, from initial evidence about nerve development, through the ...
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This chapter examines the neuromolecular and plastic brain. Ideas about plasticity and the openness of brains to environment influences, from initial evidence about nerve development, through the recognition that synaptic plasticity was the very basis of learning and memory, to evidence about the influence of environment on gene expression and the persistence throughout life of the capacity to make new neurons—all this made the neuromolecular brain seem exquisitely open to its milieu, with changes at the molecular level occurring throughout the course of a human life and thus shaping the growth, organization, and regeneration of neurons and neuronal circuits at time scales from the millisecond to the decade. This was an opportunity to explore the myriad ways in which the milieu got “under the skin,” implying an openness of these molecular processes of the brain to biography, sociality, and culture, and hence perhaps even to history and politics.Less
This chapter examines the neuromolecular and plastic brain. Ideas about plasticity and the openness of brains to environment influences, from initial evidence about nerve development, through the recognition that synaptic plasticity was the very basis of learning and memory, to evidence about the influence of environment on gene expression and the persistence throughout life of the capacity to make new neurons—all this made the neuromolecular brain seem exquisitely open to its milieu, with changes at the molecular level occurring throughout the course of a human life and thus shaping the growth, organization, and regeneration of neurons and neuronal circuits at time scales from the millisecond to the decade. This was an opportunity to explore the myriad ways in which the milieu got “under the skin,” implying an openness of these molecular processes of the brain to biography, sociality, and culture, and hence perhaps even to history and politics.
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/9780195342796.003.0013
- Subject:
- Neuroscience, Molecular and Cellular Systems, Development
VFO precedes electrographic seizures in vitro, as well as in vivo. The in vitro VFO is gap junction dependent, and is observed most readily in conditions when synaptic transmission is suppressed. One ...
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VFO precedes electrographic seizures in vitro, as well as in vivo. The in vitro VFO is gap junction dependent, and is observed most readily in conditions when synaptic transmission is suppressed. One hypothesis as to seizure initiation is that synaptic excitation recovers prior to synaptic inhibition, so that classical synaptically mediated seizure discharges can arise. Epileptiform discharges in vivo can also be preceded by gamma oscillations, and there is an in vitro model in which gamma activity and bursting activity alternates. The alternating activity appears to arise because of use-dependent alterations in synaptic excitation and inhibition.Less
VFO precedes electrographic seizures in vitro, as well as in vivo. The in vitro VFO is gap junction dependent, and is observed most readily in conditions when synaptic transmission is suppressed. One hypothesis as to seizure initiation is that synaptic excitation recovers prior to synaptic inhibition, so that classical synaptically mediated seizure discharges can arise. Epileptiform discharges in vivo can also be preceded by gamma oscillations, and there is an in vitro model in which gamma activity and bursting activity alternates. The alternating activity appears to arise because of use-dependent alterations in synaptic excitation and inhibition.
Josef P. Rauschecker
- Published in print:
- 2006
- Published Online:
- September 2009
- ISBN:
- 9780198528999
- eISBN:
- 9780191723926
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198528999.003.0021
- Subject:
- Neuroscience, Disorders of the Nervous System
This chapter considers adaptive plasticity which allows experience-based cortical expansion within a modality if used as a model for the cross-modal plasticity accompanying the loss of a sense. This ...
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This chapter considers adaptive plasticity which allows experience-based cortical expansion within a modality if used as a model for the cross-modal plasticity accompanying the loss of a sense. This plasticity is shown through auditory and somatosensory activity in occipital cortex in blind subjects. Hebbian principles are thought to be the underlying mechanism of this reorganization.Less
This chapter considers adaptive plasticity which allows experience-based cortical expansion within a modality if used as a model for the cross-modal plasticity accompanying the loss of a sense. This plasticity is shown through auditory and somatosensory activity in occipital cortex in blind subjects. Hebbian principles are thought to be the underlying mechanism of this reorganization.
Graham Bell
- Published in print:
- 2007
- Published Online:
- May 2008
- ISBN:
- 9780198569725
- eISBN:
- 9780191717741
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198569725.003.0008
- Subject:
- Biology, Evolutionary Biology / Genetics
Selection in complex and structured environments is likely to cause the divergence of differently adapted lines. This will lead to a diverse array of specialized types, or to one or a few broad ...
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Selection in complex and structured environments is likely to cause the divergence of differently adapted lines. This will lead to a diverse array of specialized types, or to one or a few broad generalists, or to some intermediate situation. The first section in this chapter is called GxE and details the ecogenetic landscape; the magnitude of GxE; inconsistency and responsiveness; the genetic correlation in relation to environmental variance; the outcome of selection in different environments; stability and responsiveness; and the evolution of stability and responsiveness. The second section is about specialization and generalization, and details niche separation; the cost of adaptation; divergent specialization; sources of antagonism: functional interference; sources of antagonism: mutational degradation; and the consequences of interference and degradation. It also gives an experimental adaptive radiation regarding pseudomonas and an historical adaptive radiation concerning anolis. The third section called Opportunities in space, obligations in time, explains simple environments; complex environments; the cost of adaptation in complex environments; structured environments; the outcome of selection in structured environments; fluctuating fitness; and the outcome of selection in variable environments. The final section is called Local adaptation and details the precision of local adaptation and gives reciprocal transplant experiments.Less
Selection in complex and structured environments is likely to cause the divergence of differently adapted lines. This will lead to a diverse array of specialized types, or to one or a few broad generalists, or to some intermediate situation. The first section in this chapter is called GxE and details the ecogenetic landscape; the magnitude of GxE; inconsistency and responsiveness; the genetic correlation in relation to environmental variance; the outcome of selection in different environments; stability and responsiveness; and the evolution of stability and responsiveness. The second section is about specialization and generalization, and details niche separation; the cost of adaptation; divergent specialization; sources of antagonism: functional interference; sources of antagonism: mutational degradation; and the consequences of interference and degradation. It also gives an experimental adaptive radiation regarding pseudomonas and an historical adaptive radiation concerning anolis. The third section called Opportunities in space, obligations in time, explains simple environments; complex environments; the cost of adaptation in complex environments; structured environments; the outcome of selection in structured environments; fluctuating fitness; and the outcome of selection in variable environments. The final section is called Local adaptation and details the precision of local adaptation and gives reciprocal transplant experiments.
Gregory P. Cheplick and Stanley H. Faeth
- Published in print:
- 2009
- Published Online:
- January 2009
- ISBN:
- 9780195308082
- eISBN:
- 9780199867462
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195308082.003.0004
- Subject:
- Biology, Ecology
For ongoing coevolution of the grass-endophyte symbiosis through the agents of natural selection, there must be genetic variation within populations for both host and endophyte. The breeding systems ...
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For ongoing coevolution of the grass-endophyte symbiosis through the agents of natural selection, there must be genetic variation within populations for both host and endophyte. The breeding systems of both symbiotic partners influence the distribution and level of genetic variation within populations. Traditional reaction norms and symbiotic interaction norms can be useful in depicting host genotype interactions with environment and infection. Examples are provided for both agronomic and native grass-endophyte symbioses. Endophytes can also modulate phenotypic plasticity of their grass hosts in relation to environmental variation. There is evidence that endophyte genotypes (haplotypes) can differ significantly in their impact on host growth and physiology. Genetic diversity of endophyte isolates has been quantified using isozymes and DNA markers. Host-endophyte compatibility can vary among endophytes and their host grasses as revealed by reciprocal inoculation experiments using fungal isolates from different host populations or species. Multistrain infections of single grass hosts and fungal hybridization within individual hosts have been determined for some symbioses. Genetic variation in both host and endophyte will expedite the continued coevolution of the symbiosis.Less
For ongoing coevolution of the grass-endophyte symbiosis through the agents of natural selection, there must be genetic variation within populations for both host and endophyte. The breeding systems of both symbiotic partners influence the distribution and level of genetic variation within populations. Traditional reaction norms and symbiotic interaction norms can be useful in depicting host genotype interactions with environment and infection. Examples are provided for both agronomic and native grass-endophyte symbioses. Endophytes can also modulate phenotypic plasticity of their grass hosts in relation to environmental variation. There is evidence that endophyte genotypes (haplotypes) can differ significantly in their impact on host growth and physiology. Genetic diversity of endophyte isolates has been quantified using isozymes and DNA markers. Host-endophyte compatibility can vary among endophytes and their host grasses as revealed by reciprocal inoculation experiments using fungal isolates from different host populations or species. Multistrain infections of single grass hosts and fungal hybridization within individual hosts have been determined for some symbioses. Genetic variation in both host and endophyte will expedite the continued coevolution of the symbiosis.
Frank Johansson and Dirk Johannes Mikolajewski
- Published in print:
- 2008
- Published Online:
- September 2008
- ISBN:
- 9780199230693
- eISBN:
- 9780191710889
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199230693.003.0010
- Subject:
- Biology, Ecology, Animal Biology
Understanding the ecology and evolution of morphological defences in animals and plants may help us to understand and protect biodiversity. Several species of dragonfly larvae express lateral and ...
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Understanding the ecology and evolution of morphological defences in animals and plants may help us to understand and protect biodiversity. Several species of dragonfly larvae express lateral and dorsal abdominal spines. In some species these spines seem to be fixed, and in others they are induced by the presence of predatory fish. Larger spines are adaptations to reduce predation risk by fish, but incur a cost because large spines are associated with a higher predation risk by invertebrate predators. The difference in vulnerability to different predators has the potential to affect temporal and spatial variation in the morphology of dragonfly larvae, and may ultimately result in speciation. Future focus on the joint evolution of correlated defensive traits such as morphology and behaviour and their plasticity might be fruitful for a better understanding of the development of animal diversity.Less
Understanding the ecology and evolution of morphological defences in animals and plants may help us to understand and protect biodiversity. Several species of dragonfly larvae express lateral and dorsal abdominal spines. In some species these spines seem to be fixed, and in others they are induced by the presence of predatory fish. Larger spines are adaptations to reduce predation risk by fish, but incur a cost because large spines are associated with a higher predation risk by invertebrate predators. The difference in vulnerability to different predators has the potential to affect temporal and spatial variation in the morphology of dragonfly larvae, and may ultimately result in speciation. Future focus on the joint evolution of correlated defensive traits such as morphology and behaviour and their plasticity might be fruitful for a better understanding of the development of animal diversity.
David C. Rowland and Clifford G. Kentros
- Published in print:
- 2008
- Published Online:
- May 2008
- ISBN:
- 9780195323245
- eISBN:
- 9780199869268
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195323245.003.0008
- Subject:
- Psychology, Cognitive Neuroscience
This chapter examines the hypothesis that attention aids memory formation by providing neuromodulatory input that turns transient, homosynaptic plasticity to long-lasting heterosynaptic plasticity. ...
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This chapter examines the hypothesis that attention aids memory formation by providing neuromodulatory input that turns transient, homosynaptic plasticity to long-lasting heterosynaptic plasticity. It addresses the following questions. Are the firing patterns of hippocampal neurons learned? Do they require plasticity like that seen in reduced hippocampal preparations? Are the firing properties of hippocampal neurons attentionally modulated? Evidence suggests that place fields require experience to be constructed, and that plasticity is involved in this process, thus, the first two questions can be answered positively even though the mechanistic details remain elusive. However, the role of attention in the firing patterns of hippocampal neurons, remains more problematic. This is not surprising because this part deals with cognitive rather than cellular mechanisms, and the mechanistic understanding of cognitive neuroscience is still in its infancy relative to that of cellular neuroscience.Less
This chapter examines the hypothesis that attention aids memory formation by providing neuromodulatory input that turns transient, homosynaptic plasticity to long-lasting heterosynaptic plasticity. It addresses the following questions. Are the firing patterns of hippocampal neurons learned? Do they require plasticity like that seen in reduced hippocampal preparations? Are the firing properties of hippocampal neurons attentionally modulated? Evidence suggests that place fields require experience to be constructed, and that plasticity is involved in this process, thus, the first two questions can be answered positively even though the mechanistic details remain elusive. However, the role of attention in the firing patterns of hippocampal neurons, remains more problematic. This is not surprising because this part deals with cognitive rather than cellular mechanisms, and the mechanistic understanding of cognitive neuroscience is still in its infancy relative to that of cellular neuroscience.
Gary L. Wenk
- Published in print:
- 2010
- Published Online:
- September 2010
- ISBN:
- 9780195388541
- eISBN:
- 9780199863587
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195388541.003.0006
- Subject:
- Neuroscience, Behavioral Neuroscience, Neuroendocrine and Autonomic
Glutamate is an amino acid that your brain uses as a neurotransmitter and it is almost always is excitatory. GABA is also an amino acid that your brain uses as a neurotransmitter and it is almost ...
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Glutamate is an amino acid that your brain uses as a neurotransmitter and it is almost always is excitatory. GABA is also an amino acid that your brain uses as a neurotransmitter and it is almost always inhibitory. These two neurotransmitters are widespread in your brain and tend to compete for turning your neurons on or off. Glutamate makes and breaks connections between neurons; this action allows your brain to learn. For example, if you consume a chemical that blocks the actions of glutamate you become amnestic, unable to remember anything new. The street drugs PCP and ketamine block glutamate receptors and depress the activity of your brain. Your brain makes its own PCP-like neurotransmitter called angeldustin. Chemicals that enhance the action of GABA, such as alcohol, barbiturates, or any of the popular drugs related to Valium and Librium, can make us sleepy, send us into a coma, or kill us by turning off too many neurons in the brain.Less
Glutamate is an amino acid that your brain uses as a neurotransmitter and it is almost always is excitatory. GABA is also an amino acid that your brain uses as a neurotransmitter and it is almost always inhibitory. These two neurotransmitters are widespread in your brain and tend to compete for turning your neurons on or off. Glutamate makes and breaks connections between neurons; this action allows your brain to learn. For example, if you consume a chemical that blocks the actions of glutamate you become amnestic, unable to remember anything new. The street drugs PCP and ketamine block glutamate receptors and depress the activity of your brain. Your brain makes its own PCP-like neurotransmitter called angeldustin. Chemicals that enhance the action of GABA, such as alcohol, barbiturates, or any of the popular drugs related to Valium and Librium, can make us sleepy, send us into a coma, or kill us by turning off too many neurons in the brain.
Motoy Kuno
- Published in print:
- 1994
- Published Online:
- March 2012
- ISBN:
- 9780198546870
- eISBN:
- 9780191724350
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198546870.001.0001
- Subject:
- Neuroscience, Molecular and Cellular Systems
The synapse not only provides a bridge from one nerve cell to the next; its function can be modified by experience, making it important for learning and memory. This overview of the synapse provides ...
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The synapse not only provides a bridge from one nerve cell to the next; its function can be modified by experience, making it important for learning and memory. This overview of the synapse provides a review of current concepts in neurobiology, with specific reference to synaptic plasticity, neurotransmission, and neurotrophism. These areas have been advanced dramatically by the application of molecular biology techniques, and this book provides a synthesis of these advances. The book incorporates all the latest thinking and current research together with a brief historical overview of research in the field.Less
The synapse not only provides a bridge from one nerve cell to the next; its function can be modified by experience, making it important for learning and memory. This overview of the synapse provides a review of current concepts in neurobiology, with specific reference to synaptic plasticity, neurotransmission, and neurotrophism. These areas have been advanced dramatically by the application of molecular biology techniques, and this book provides a synthesis of these advances. The book incorporates all the latest thinking and current research together with a brief historical overview of research in the field.
Luis Miguel García-Segura
- Published in print:
- 2009
- Published Online:
- May 2009
- ISBN:
- 9780195326611
- eISBN:
- 9780199864881
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195326611.003.0001
- Subject:
- Neuroscience, Behavioral Neuroscience, Neuroendocrine and Autonomic
This chapter begins with a discussion of the concepts of homeostasis, allostasis, homeodynamics, brain plasticity, and endocrine glands. It then discusses cellular plasticity, cellular replacement, ...
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This chapter begins with a discussion of the concepts of homeostasis, allostasis, homeodynamics, brain plasticity, and endocrine glands. It then discusses cellular plasticity, cellular replacement, brain plasticity, and the role of hormones in brain mutability.Less
This chapter begins with a discussion of the concepts of homeostasis, allostasis, homeodynamics, brain plasticity, and endocrine glands. It then discusses cellular plasticity, cellular replacement, brain plasticity, and the role of hormones in brain mutability.
Manfred Fahle and Mark Greenlee (eds)
- Published in print:
- 2003
- Published Online:
- March 2012
- ISBN:
- 9780198505822
- eISBN:
- 9780191686900
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198505822.001.0001
- Subject:
- Psychology, Neuropsychology
This book describes a range of new approaches to neuropsychological investigation and provides a broad overview of visual neuropsychology. It starts by presenting the results from new research ...
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This book describes a range of new approaches to neuropsychological investigation and provides a broad overview of visual neuropsychology. It starts by presenting the results from new research employing single-unit recordings on the neuronal basis of perception demonstrating that the visual system relies strongly on feedback from higher to lower levels of information processing, and that neuronal plasticity exists in the primary sensory cortices of adults, areas previously considered to be hard-wired. The book also describes other new and adapted techniques to measure brain activity, including multi-unit sum potential recording, functional magnetic resonance imaging and employing transcranial magnetic stimulation to induce temporary, circumscribed functional lesions in the cortices of normal subjects to mimic disorders. The coverage then moves on to review the experience of patients suffering from disturbances of visual perception. The disorders covered include agnosia, neglect, blindsight, and achromatopsia. The final chapter is devoted to recovery and rehabilitation from cerebral visual disorder.Less
This book describes a range of new approaches to neuropsychological investigation and provides a broad overview of visual neuropsychology. It starts by presenting the results from new research employing single-unit recordings on the neuronal basis of perception demonstrating that the visual system relies strongly on feedback from higher to lower levels of information processing, and that neuronal plasticity exists in the primary sensory cortices of adults, areas previously considered to be hard-wired. The book also describes other new and adapted techniques to measure brain activity, including multi-unit sum potential recording, functional magnetic resonance imaging and employing transcranial magnetic stimulation to induce temporary, circumscribed functional lesions in the cortices of normal subjects to mimic disorders. The coverage then moves on to review the experience of patients suffering from disturbances of visual perception. The disorders covered include agnosia, neglect, blindsight, and achromatopsia. The final chapter is devoted to recovery and rehabilitation from cerebral visual disorder.
R. Ford Denison
- Published in print:
- 2012
- Published Online:
- October 2017
- ISBN:
- 9780691139500
- eISBN:
- 9781400842810
- Item type:
- chapter
- Publisher:
- Princeton University Press
- DOI:
- 10.23943/princeton/9780691139500.003.0012
- Subject:
- Biology, Evolutionary Biology / Genetics
This chapter summarizes the book's main conclusions and cautions against exclusive reliance on any single approach. The book's central thesis is that nature's wisdom is found primarily in ...
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This chapter summarizes the book's main conclusions and cautions against exclusive reliance on any single approach. The book's central thesis is that nature's wisdom is found primarily in competitively tested individual adaptations, in wild species and sometimes still in cultivated ones, rather than in the overall structure of natural ecosystems. It notes how some biotechnology advocates underestimate the perfection of existing individual adaptations and suggests that most near-term opportunities for genetic improvement of crops or livestock will involve tradeoffs that had constrained natural selection in the past. The chapter considers two basic approaches to the problem of varying environments: phenotypic plasticity and bet-hedging. It also discusses bet-hedging in food production, the bet-hedging benefits of organic farming and animal agriculture, and the use of diversity for bet-hedging in agricultural research. Finally, it describes traditional agricultural sciences that have been more receptive to input from evolutionary biology than biotechnology has.Less
This chapter summarizes the book's main conclusions and cautions against exclusive reliance on any single approach. The book's central thesis is that nature's wisdom is found primarily in competitively tested individual adaptations, in wild species and sometimes still in cultivated ones, rather than in the overall structure of natural ecosystems. It notes how some biotechnology advocates underestimate the perfection of existing individual adaptations and suggests that most near-term opportunities for genetic improvement of crops or livestock will involve tradeoffs that had constrained natural selection in the past. The chapter considers two basic approaches to the problem of varying environments: phenotypic plasticity and bet-hedging. It also discusses bet-hedging in food production, the bet-hedging benefits of organic farming and animal agriculture, and the use of diversity for bet-hedging in agricultural research. Finally, it describes traditional agricultural sciences that have been more receptive to input from evolutionary biology than biotechnology has.
F. Woodward Hopf, Antonello Bonci, and Robert C. Malenka
- Published in print:
- 2009
- Published Online:
- February 2010
- ISBN:
- 9780195373035
- eISBN:
- 9780199865543
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195373035.003.0024
- Subject:
- Neuroscience, Molecular and Cellular Systems, History of Neuroscience
This chapter reviews current understanding of how dopamine (DA) might modulate glutamatergic synaptic plasticity in mesolimbic brain regions. This topic is examined in the context of in vitro brain ...
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This chapter reviews current understanding of how dopamine (DA) might modulate glutamatergic synaptic plasticity in mesolimbic brain regions. This topic is examined in the context of in vitro brain slice experiments and plasticity induction in the anesthetized animal. The possibility that DA modulation of glutamatergic signaling could occur in the awake animal and contribute to the expression of motivated behavior is discussed.Less
This chapter reviews current understanding of how dopamine (DA) might modulate glutamatergic synaptic plasticity in mesolimbic brain regions. This topic is examined in the context of in vitro brain slice experiments and plasticity induction in the anesthetized animal. The possibility that DA modulation of glutamatergic signaling could occur in the awake animal and contribute to the expression of motivated behavior is discussed.
Xavier E. Cagigas and Robert M. Bilder
- Published in print:
- 2009
- Published Online:
- February 2010
- ISBN:
- 9780195176704
- eISBN:
- 9780199864706
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195176704.003.0003
- Subject:
- Neuroscience, History of Neuroscience
This chapter utilizes A.R. Luria’s method of neuropsychological investigation to shed light upon recent advances in neuroimaging and emerging paradigms in the cognitive neurosciences such as ...
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This chapter utilizes A.R. Luria’s method of neuropsychological investigation to shed light upon recent advances in neuroimaging and emerging paradigms in the cognitive neurosciences such as cognitive phenomics. Particular attention is focused on the theoretical power of Luria’s method for understanding the emerging literature in cultural neuropsychology which is challenging the notion of psychic unity and revolutionizing the field’s understanding of cognition. An argument is made for embracing biological and cultural diversity by recasting neurocognition as being completely culturally-constituted. Other themes covered in the chapter include: Goldberg’s gradiental theory, activity theory, the effects of bilingualism and other experience-based influences on brain plasticity, biocultural co-constructivism, and the cultural-historical method for understanding neurocognition.Less
This chapter utilizes A.R. Luria’s method of neuropsychological investigation to shed light upon recent advances in neuroimaging and emerging paradigms in the cognitive neurosciences such as cognitive phenomics. Particular attention is focused on the theoretical power of Luria’s method for understanding the emerging literature in cultural neuropsychology which is challenging the notion of psychic unity and revolutionizing the field’s understanding of cognition. An argument is made for embracing biological and cultural diversity by recasting neurocognition as being completely culturally-constituted. Other themes covered in the chapter include: Goldberg’s gradiental theory, activity theory, the effects of bilingualism and other experience-based influences on brain plasticity, biocultural co-constructivism, and the cultural-historical method for understanding neurocognition.
Howard Eichenbaum and Neal J. Cohen
- Published in print:
- 2004
- Published Online:
- January 2008
- ISBN:
- 9780195178043
- eISBN:
- 9780199871223
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195178043.001.0001
- Subject:
- Psychology, Cognitive Psychology
This book provides a comprehensive treatment of the history and implications of the notion of multiple memory systems, of the evidence that supports it, and of the nature of the systems discovered so ...
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This book provides a comprehensive treatment of the history and implications of the notion of multiple memory systems, of the evidence that supports it, and of the nature of the systems discovered so far. The book begins by highlighting a brief history of ideas about multiple memory systems and how those ideas fit into the story of the progression of our understanding of the nature and organization of memory in the brain. Other early chapters address some of the themes and principles that are common to all memory systems, including the fundamentals of cellular plasticity and the critical role of the cerebral cortex in memory. The central portion of the book then attempts to characterize the role of several specific memory systems, starting with a detailed analysis of the hippocampal memory system — the brain system that mediates declarative memory, our ability to recollect consciously everyday facts and experiences, by supporting the capacity for relational memory processing. Individual chapters focus on non-human primate and rodent models of amnesia, on hippocampal neuronal activity, and on the permanent consolidation of declarative memories. Subsequent chapters present evidence of functional dissociations among various memory systems. These chapters identify and describe brain systems that mediate emotional memories, modulate memory, or mediate the acquisition of behavioral habits (procedural memory), all concerned with long-term memory abilities, and a system focused on the prefrontal cortex that supports working memory.Less
This book provides a comprehensive treatment of the history and implications of the notion of multiple memory systems, of the evidence that supports it, and of the nature of the systems discovered so far. The book begins by highlighting a brief history of ideas about multiple memory systems and how those ideas fit into the story of the progression of our understanding of the nature and organization of memory in the brain. Other early chapters address some of the themes and principles that are common to all memory systems, including the fundamentals of cellular plasticity and the critical role of the cerebral cortex in memory. The central portion of the book then attempts to characterize the role of several specific memory systems, starting with a detailed analysis of the hippocampal memory system — the brain system that mediates declarative memory, our ability to recollect consciously everyday facts and experiences, by supporting the capacity for relational memory processing. Individual chapters focus on non-human primate and rodent models of amnesia, on hippocampal neuronal activity, and on the permanent consolidation of declarative memories. Subsequent chapters present evidence of functional dissociations among various memory systems. These chapters identify and describe brain systems that mediate emotional memories, modulate memory, or mediate the acquisition of behavioral habits (procedural memory), all concerned with long-term memory abilities, and a system focused on the prefrontal cortex that supports working memory.
Wolf U. Blanckenhorn, Rudolf Meier, and Tiit Teder
- Published in print:
- 2007
- Published Online:
- September 2007
- ISBN:
- 9780199208784
- eISBN:
- 9780191709036
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199208784.003.0007
- Subject:
- Biology, Animal Biology
Rensch's rule is a common pattern of allometry for sexual size dimorphism among animal species. This chapter evaluates Rensch's rule in insects, using three levels of analysis. When comparisons are ...
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Rensch's rule is a common pattern of allometry for sexual size dimorphism among animal species. This chapter evaluates Rensch's rule in insects, using three levels of analysis. When comparisons are made among species, Rensch's rule is not more common than that which would be expected by chance: it occurs in Diptera (flies) and Heteroptera (Gerridae; water striders), but not in other insect groups. Comparisons among populations within species also show little evidence of Rensch's rule, although when the populations were ordered by latitude, Rensch's rule was more common than that which would be expected by chance. Within populations, body size tends to be more phenotypically plastic in females than in males, resulting in allometry opposite to Rensch's rule. Data on scathophagid and sepsid flies show that patterns across the three levels of comparison do not correspond well. Thus, in insects, neither the allometric patterns nor their causative processes can be generalized among taxa or among levels of analysis.Less
Rensch's rule is a common pattern of allometry for sexual size dimorphism among animal species. This chapter evaluates Rensch's rule in insects, using three levels of analysis. When comparisons are made among species, Rensch's rule is not more common than that which would be expected by chance: it occurs in Diptera (flies) and Heteroptera (Gerridae; water striders), but not in other insect groups. Comparisons among populations within species also show little evidence of Rensch's rule, although when the populations were ordered by latitude, Rensch's rule was more common than that which would be expected by chance. Within populations, body size tends to be more phenotypically plastic in females than in males, resulting in allometry opposite to Rensch's rule. Data on scathophagid and sepsid flies show that patterns across the three levels of comparison do not correspond well. Thus, in insects, neither the allometric patterns nor their causative processes can be generalized among taxa or among levels of analysis.
Michael J. Angilletta Jr.
- Published in print:
- 2009
- Published Online:
- May 2009
- ISBN:
- 9780198570875
- eISBN:
- 9780191718748
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198570875.001.1
- Subject:
- Biology, Ecology, Animal Biology
Temperature pervasively impacts the phenotypes and distributions of organisms. These thermal effects generate strong selective pressures on behaviour, physiology, and life history when environmental ...
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Temperature pervasively impacts the phenotypes and distributions of organisms. These thermal effects generate strong selective pressures on behaviour, physiology, and life history when environmental temperatures vary over space and time. Despite this fact, progress toward a quantitative theory of thermal adaptation has lagged behind empirical descriptions of patterns and processes. This book draws on current evolutionary paradigms (optimization, quantitative genetics, and genetic algorithms) to establish a theory of thermal adaptation. It initially focuses on simple models that describe the evolution of thermosensitivity, thermoregulation, or acclimation. Later chapters focus on more complex models describing the coadaptation of traits or the coevolution of species. Throughout the book, various lines of evidence are used to question the major assumptions of these models. Furthermore, the predictions of these models are confronted with experimental and comparative data. Empirical examples represent a wide range of taxa, including bacteria, plants, fungi, and animals. The result is a synthesis of theoretical and empirical studies of thermal biology that offers insights about evolutionary processes.Less
Temperature pervasively impacts the phenotypes and distributions of organisms. These thermal effects generate strong selective pressures on behaviour, physiology, and life history when environmental temperatures vary over space and time. Despite this fact, progress toward a quantitative theory of thermal adaptation has lagged behind empirical descriptions of patterns and processes. This book draws on current evolutionary paradigms (optimization, quantitative genetics, and genetic algorithms) to establish a theory of thermal adaptation. It initially focuses on simple models that describe the evolution of thermosensitivity, thermoregulation, or acclimation. Later chapters focus on more complex models describing the coadaptation of traits or the coevolution of species. Throughout the book, various lines of evidence are used to question the major assumptions of these models. Furthermore, the predictions of these models are confronted with experimental and comparative data. Empirical examples represent a wide range of taxa, including bacteria, plants, fungi, and animals. The result is a synthesis of theoretical and empirical studies of thermal biology that offers insights about evolutionary processes.
Ellen Kalmbach and Maria M. Benito
- Published in print:
- 2007
- Published Online:
- September 2007
- ISBN:
- 9780199208784
- eISBN:
- 9780191709036
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199208784.003.0015
- Subject:
- Biology, Animal Biology
This chapter uses recent experimental and observational studies of birds to explore patterns of sex-specific offspring vulnerability (increased mortality and reduced fledging mass under poor ...
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This chapter uses recent experimental and observational studies of birds to explore patterns of sex-specific offspring vulnerability (increased mortality and reduced fledging mass under poor conditions) in relation to sexual size dimorphism (SSD). The results show size-dependent modulation of male fledgling mass but size-independent mass reduction in females. Overall, growth is more phenotypically plastic in males than in females. Comparisons of fledging mass reached in ‘good’ and ‘poor’ environments suggest that having to grow large is mainly disadvantageous when coupled with the male phenotype. Differences in environmental sensitivity between the two sexes during ontogeny, either in the form of increased mortality or reduced body size, will tend to reduce dimorphism during development, affecting adult SSD. These results suggest that environmental conditions during ontogeny contribute significantly to variation in SSD within bird species, particularly when comparisons are made among environments or between generations.Less
This chapter uses recent experimental and observational studies of birds to explore patterns of sex-specific offspring vulnerability (increased mortality and reduced fledging mass under poor conditions) in relation to sexual size dimorphism (SSD). The results show size-dependent modulation of male fledgling mass but size-independent mass reduction in females. Overall, growth is more phenotypically plastic in males than in females. Comparisons of fledging mass reached in ‘good’ and ‘poor’ environments suggest that having to grow large is mainly disadvantageous when coupled with the male phenotype. Differences in environmental sensitivity between the two sexes during ontogeny, either in the form of increased mortality or reduced body size, will tend to reduce dimorphism during development, affecting adult SSD. These results suggest that environmental conditions during ontogeny contribute significantly to variation in SSD within bird species, particularly when comparisons are made among environments or between generations.
Turk Rhen
- Published in print:
- 2007
- Published Online:
- September 2007
- ISBN:
- 9780199208784
- eISBN:
- 9780191709036
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199208784.003.0019
- Subject:
- Biology, Animal Biology
Females and males share the same genome, which places a significant constraint on the evolution of sex differences. This chapter begins with a review of current theory explaining the initial ...
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Females and males share the same genome, which places a significant constraint on the evolution of sex differences. This chapter begins with a review of current theory explaining the initial evolution of anisogamy and subsequent differentiation of the sexes. It then describes four mechanisms that relieve constraints on sexual differentiation: (i) genetic differences between the sexes; (ii) sex-limited or differential expression of autosomal loci; (iii) trans-generational epigenetic effects; and (iv) phenotypic plasticity for sexual traits (i.e., environmental influences on sexual development). All four mechanisms have evolved convergently in different evolutionary lineages. The chapter closes by advocating research programmes that integrate evolutionary and mechanistic approaches to discover how sex-specific selection interacts with genetic (and physiological) variation to produce sexual dimorphism.Less
Females and males share the same genome, which places a significant constraint on the evolution of sex differences. This chapter begins with a review of current theory explaining the initial evolution of anisogamy and subsequent differentiation of the sexes. It then describes four mechanisms that relieve constraints on sexual differentiation: (i) genetic differences between the sexes; (ii) sex-limited or differential expression of autosomal loci; (iii) trans-generational epigenetic effects; and (iv) phenotypic plasticity for sexual traits (i.e., environmental influences on sexual development). All four mechanisms have evolved convergently in different evolutionary lineages. The chapter closes by advocating research programmes that integrate evolutionary and mechanistic approaches to discover how sex-specific selection interacts with genetic (and physiological) variation to produce sexual dimorphism.
