Xun Gu
- Published in print:
- 2010
- Published Online:
- January 2011
- ISBN:
- 9780199213269
- eISBN:
- 9780191594762
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199213269.003.0007
- Subject:
- Biology, Biomathematics / Statistics and Data Analysis / Complexity Studies
Understanding the underlying regulatory mechanism is a fundamental step to exploring the emergence of genome complexity. An important issue is the role of tissue-specific factors in genomic ...
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Understanding the underlying regulatory mechanism is a fundamental step to exploring the emergence of genome complexity. An important issue is the role of tissue-specific factors in genomic evolution. Several studies have suggested that tissue-specific constraints may generate among tissue variation of expression divergence between humans and chimpanzees, between humans and mice, or between fruitflies. Duret and Mouchiroud showed that the rate of protein divergence was negatively associated with the tissue broadness of gene expression. This chapter first discusses the tissue-driven hypothesis, based on an explicit evolutionary model for providing testable predictions. This theory claims that stabilizing selections for both expression and sequence divergences may be affected simultaneously by common tissue factors. It then addresses an interesting problem about the expression evolution in the human brain since the separate development of humans and chimpanzees.Less
Understanding the underlying regulatory mechanism is a fundamental step to exploring the emergence of genome complexity. An important issue is the role of tissue-specific factors in genomic evolution. Several studies have suggested that tissue-specific constraints may generate among tissue variation of expression divergence between humans and chimpanzees, between humans and mice, or between fruitflies. Duret and Mouchiroud showed that the rate of protein divergence was negatively associated with the tissue broadness of gene expression. This chapter first discusses the tissue-driven hypothesis, based on an explicit evolutionary model for providing testable predictions. This theory claims that stabilizing selections for both expression and sequence divergences may be affected simultaneously by common tissue factors. It then addresses an interesting problem about the expression evolution in the human brain since the separate development of humans and chimpanzees.
Paul Nunez
- Published in print:
- 2010
- Published Online:
- May 2010
- ISBN:
- 9780195340716
- eISBN:
- 9780199776269
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195340716.001.0001
- Subject:
- Neuroscience, Development
Does the brain create the mind, or is some external entity involved? In addressing this hard problem of consciousness, we face a central human challenge: what do we really know and how do we know it? ...
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Does the brain create the mind, or is some external entity involved? In addressing this hard problem of consciousness, we face a central human challenge: what do we really know and how do we know it? Tentative answers in this book follow from a synthesis of profound ideas, borrowed from philosophy, religion, politics, economics, neuroscience, physics, mathematics, and cosmology, the knowledge structures supporting our meager grasp of reality. This search for new links in the web of human knowledge extends in many directions: the shadows of our thought processes revealed by brain imagining, brains treated as complex adaptive systems that reveal fractal-like behavior in the brain's nested hierarchy, resonant interactions facilitating functional connections in brain tissue, probability and entropy as measures of human ignorance, fundamental limits on human knowledge, and the central role played by information in both brains and physical systems. The author discusses the possibility of deep connections between relativity, quantum mechanics, thermodynamics, and consciousness; all entities involved with fundamental information barriers. This study elaborates on possible new links in this nested web of human knowledge that may tell us something new about the nature and origins of consciousness. In the end, does the brain create the mind? Or is the mind already out there?Less
Does the brain create the mind, or is some external entity involved? In addressing this hard problem of consciousness, we face a central human challenge: what do we really know and how do we know it? Tentative answers in this book follow from a synthesis of profound ideas, borrowed from philosophy, religion, politics, economics, neuroscience, physics, mathematics, and cosmology, the knowledge structures supporting our meager grasp of reality. This search for new links in the web of human knowledge extends in many directions: the shadows of our thought processes revealed by brain imagining, brains treated as complex adaptive systems that reveal fractal-like behavior in the brain's nested hierarchy, resonant interactions facilitating functional connections in brain tissue, probability and entropy as measures of human ignorance, fundamental limits on human knowledge, and the central role played by information in both brains and physical systems. The author discusses the possibility of deep connections between relativity, quantum mechanics, thermodynamics, and consciousness; all entities involved with fundamental information barriers. This study elaborates on possible new links in this nested web of human knowledge that may tell us something new about the nature and origins of consciousness. In the end, does the brain create the mind? Or is the mind already out there?
Milena D. Bister
- Published in print:
- 2011
- Published Online:
- May 2011
- ISBN:
- 9780199587551
- eISBN:
- 9780191725630
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199587551.003.0018
- Subject:
- Public Health and Epidemiology, Public Health
This concluding chapter briefly highlights the main results of the preceding chapters and poses some vital questions that are still unanswered in the field of human tissue research: How can the ...
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This concluding chapter briefly highlights the main results of the preceding chapters and poses some vital questions that are still unanswered in the field of human tissue research: How can the regulatory efforts of Member states be translated to the supranational level of the European Union and the Council of Europe? How can diverging standards in the handling of new and existing tissue collections be avoided? How are individual interests to be weighed against the public good? Finally, should a joint regulatory approach be established in the European Union?Less
This concluding chapter briefly highlights the main results of the preceding chapters and poses some vital questions that are still unanswered in the field of human tissue research: How can the regulatory efforts of Member states be translated to the supranational level of the European Union and the Council of Europe? How can diverging standards in the handling of new and existing tissue collections be avoided? How are individual interests to be weighed against the public good? Finally, should a joint regulatory approach be established in the European Union?
Mike Savage
- Published in print:
- 2010
- Published Online:
- May 2012
- ISBN:
- 9780199587650
- eISBN:
- 9780191740626
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199587650.003.0011
- Subject:
- Sociology, Comparative and Historical Sociology
This chapter sums up arguments about the politics of method and the key findings of this study on socio-cultural change in Great Britain during the period between 1940 and 1970. It describes the ...
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This chapter sums up arguments about the politics of method and the key findings of this study on socio-cultural change in Great Britain during the period between 1940 and 1970. It describes the battery of techniques and methods that could be used to expose the social tissue during the post-war decades, and the technical identities associated with them. The chapter also highlights how the social sciences systematically conceal their own tracks through their deployment of ethical issues as a kind of screen that distinguishes past from present.Less
This chapter sums up arguments about the politics of method and the key findings of this study on socio-cultural change in Great Britain during the period between 1940 and 1970. It describes the battery of techniques and methods that could be used to expose the social tissue during the post-war decades, and the technical identities associated with them. The chapter also highlights how the social sciences systematically conceal their own tracks through their deployment of ethical issues as a kind of screen that distinguishes past from present.
Pat Willmer
- Published in print:
- 2011
- Published Online:
- October 2017
- ISBN:
- 9780691128610
- eISBN:
- 9781400838943
- Item type:
- chapter
- Publisher:
- Princeton University Press
- DOI:
- 10.23943/princeton/9780691128610.003.0009
- Subject:
- Biology, Ecology
This chapter examines a variety of rewards that can be obtained by pollinators from flower visits, including oils, waxes, scents, and resins and gums. Fatty oils as an offering in flowers are now ...
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This chapter examines a variety of rewards that can be obtained by pollinators from flower visits, including oils, waxes, scents, and resins and gums. Fatty oils as an offering in flowers are now known from at least eighty genera across several families and from nearly 1 per cent of flowering plant species. Floral resins have been reported in occasional genera that are abundant in the tropics. The chapter also considers stigmatic exudates, which provide a good oily food source that sometimes can be the primary reward; examples of fragrance as a reward; floral tissues; and other possible nonfood rewards such as brood sites, microclimatic protection and warmth, and meeting places. Most of the rewards discussed in this chapter may be the key to some particularly fascinating pollination systems and open up possibilities for new dimensions in animal–flower interactions.Less
This chapter examines a variety of rewards that can be obtained by pollinators from flower visits, including oils, waxes, scents, and resins and gums. Fatty oils as an offering in flowers are now known from at least eighty genera across several families and from nearly 1 per cent of flowering plant species. Floral resins have been reported in occasional genera that are abundant in the tropics. The chapter also considers stigmatic exudates, which provide a good oily food source that sometimes can be the primary reward; examples of fragrance as a reward; floral tissues; and other possible nonfood rewards such as brood sites, microclimatic protection and warmth, and meeting places. Most of the rewards discussed in this chapter may be the key to some particularly fascinating pollination systems and open up possibilities for new dimensions in animal–flower interactions.
Brian D. Kloeppel, Mark E. Harmon, and Timothy J. Fahey
- Published in print:
- 2007
- Published Online:
- September 2007
- ISBN:
- 9780195168662
- eISBN:
- 9780199790128
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195168662.003.0005
- Subject:
- Biology, Ecology
This chapter focuses on the measurement of aboveground live biomass increment and tissue mortality in forest ecosystems. Standardized approaches for quantifying wood production, tree mortality, and ...
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This chapter focuses on the measurement of aboveground live biomass increment and tissue mortality in forest ecosystems. Standardized approaches for quantifying wood production, tree mortality, and the production of ephemeral tissues (foliage, fruits, etc.) are described in detail, including sampling strategies and precautions. The development of reliable allometric equations relating stem diameter and tree biomass is examined. A variety of special considerations, including losses to herbivory, leaching and volatilization, as well as approaches for scaling and sample adequacy determination are described.Less
This chapter focuses on the measurement of aboveground live biomass increment and tissue mortality in forest ecosystems. Standardized approaches for quantifying wood production, tree mortality, and the production of ephemeral tissues (foliage, fruits, etc.) are described in detail, including sampling strategies and precautions. The development of reliable allometric equations relating stem diameter and tree biomass is examined. A variety of special considerations, including losses to herbivory, leaching and volatilization, as well as approaches for scaling and sample adequacy determination are described.
J. S. Malik Peiris and Yi Guan
- Published in print:
- 2005
- Published Online:
- September 2007
- ISBN:
- 9780198568193
- eISBN:
- 9780191718175
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198568193.003.0006
- Subject:
- Biology, Disease Ecology / Epidemiology
An unusual atypical pneumonia emerged in the autumn of 2002 and winter of 2003, which was recognized as a new disease and designated Severe Acute Respiratory Syndrome (SARS). A novel coronavirus ...
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An unusual atypical pneumonia emerged in the autumn of 2002 and winter of 2003, which was recognized as a new disease and designated Severe Acute Respiratory Syndrome (SARS). A novel coronavirus (SARS CoV) was identified as the cause of SARS. This chapter describes the initial recognition of the new disease and the concerted international effort that allowed the rapid identification of SARS CoV as its aetiological agent. The tissue distribution of virus in infected patients is described with reference to the implications for onward human-to-human transmission. In contrast to other respiratory viral infections, the viral load of SARS CoV in the upper respiratory tract and faeces is low in the first few days of illness, and peaks around day 10 of illness. The chapter concludes with a discussion of the implications of this pattern of viral excretion.Less
An unusual atypical pneumonia emerged in the autumn of 2002 and winter of 2003, which was recognized as a new disease and designated Severe Acute Respiratory Syndrome (SARS). A novel coronavirus (SARS CoV) was identified as the cause of SARS. This chapter describes the initial recognition of the new disease and the concerted international effort that allowed the rapid identification of SARS CoV as its aetiological agent. The tissue distribution of virus in infected patients is described with reference to the implications for onward human-to-human transmission. In contrast to other respiratory viral infections, the viral load of SARS CoV in the upper respiratory tract and faeces is low in the first few days of illness, and peaks around day 10 of illness. The chapter concludes with a discussion of the implications of this pattern of viral excretion.
Stephen Wilkinson
- Published in print:
- 2010
- Published Online:
- May 2010
- ISBN:
- 9780199273966
- eISBN:
- 9780191706585
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199273966.003.0004
- Subject:
- Philosophy, Moral Philosophy, Political Philosophy
This chapter starts by evaluating the Cost of Care Argument. This is a further argument against selecting for disability, one that (unlike those considered in Chapter 3) relies not on appeals to the ...
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This chapter starts by evaluating the Cost of Care Argument. This is a further argument against selecting for disability, one that (unlike those considered in Chapter 3) relies not on appeals to the welfare of the child created but on concerns about the costs that selecting for disability would allegedly impose on health and social services. Several reasons for being sceptical or cautious about using the Cost of Care Argument to justify reproductive decisions and policies are offered. The second part of the chapter discusses the deliberate creation of a saviour sibling (a new child whose tissue might be used to save the life of an existing sick child). The case against selection saviour siblings is reviewed and generally found wanting, although unsurprisingly there may be extreme versions of this practice that are objectionable (for instance, if parents planned to discard the saviour sibling once it had ‘served its purpose’).Less
This chapter starts by evaluating the Cost of Care Argument. This is a further argument against selecting for disability, one that (unlike those considered in Chapter 3) relies not on appeals to the welfare of the child created but on concerns about the costs that selecting for disability would allegedly impose on health and social services. Several reasons for being sceptical or cautious about using the Cost of Care Argument to justify reproductive decisions and policies are offered. The second part of the chapter discusses the deliberate creation of a saviour sibling (a new child whose tissue might be used to save the life of an existing sick child). The case against selection saviour siblings is reviewed and generally found wanting, although unsurprisingly there may be extreme versions of this practice that are objectionable (for instance, if parents planned to discard the saviour sibling once it had ‘served its purpose’).
Pierluigi Frisco
- Published in print:
- 2009
- Published Online:
- September 2009
- ISBN:
- 9780199542864
- eISBN:
- 9780191715679
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199542864.003.0005
- Subject:
- Mathematics, Applied Mathematics, Mathematical Biology
This chapter presents one of the most studied models of membrane systems: P systems with symport/antiport. Their simple and elegant method of operation has caught the interest of many researchers and ...
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This chapter presents one of the most studied models of membrane systems: P systems with symport/antiport. Their simple and elegant method of operation has caught the interest of many researchers and several papers have been written on this model or inspired by the operations used by it. Some studied issues related to descriptional complexity, others considered restricted ways in which operations can be performed, others used these operations on other platforms, etc. All in all, it would be very possible to write a monograph dedicated only to P systems with symport/antiport. This chapter gives an overview and provides the proofs of the latest results on this model.Less
This chapter presents one of the most studied models of membrane systems: P systems with symport/antiport. Their simple and elegant method of operation has caught the interest of many researchers and several papers have been written on this model or inspired by the operations used by it. Some studied issues related to descriptional complexity, others considered restricted ways in which operations can be performed, others used these operations on other platforms, etc. All in all, it would be very possible to write a monograph dedicated only to P systems with symport/antiport. This chapter gives an overview and provides the proofs of the latest results on this model.
Fabian Model, Jörn Lewin, Catherine Lofton-Day, and Gunter Weiss
- Published in print:
- 2009
- Published Online:
- September 2009
- ISBN:
- 9780199532872
- eISBN:
- 9780191714467
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199532872.003.0005
- Subject:
- Mathematics, Probability / Statistics, Biostatistics
This chapter gives an overview of algorithms and statistical methods used for measuring and analyzing DNA methylation in cancer research. It starts with a short introduction into the biology of DNA ...
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This chapter gives an overview of algorithms and statistical methods used for measuring and analyzing DNA methylation in cancer research. It starts with a short introduction into the biology of DNA methylation and its role in cancer. This is followed by an overview of measurement technologies and a detailed description of data pre-processing algorithms for normalization and calibration of direct bisulphite DNA sequencing and DNA methylation microarray measurements. The second part of the chapter explores some typical examples of DNA methylation data analysis in cancer research and diagnostics: the classification of tumour tissue samples, the detection of cancer in plasma samples, and the tissue based prediction of tumour recurrence.Less
This chapter gives an overview of algorithms and statistical methods used for measuring and analyzing DNA methylation in cancer research. It starts with a short introduction into the biology of DNA methylation and its role in cancer. This is followed by an overview of measurement technologies and a detailed description of data pre-processing algorithms for normalization and calibration of direct bisulphite DNA sequencing and DNA methylation microarray measurements. The second part of the chapter explores some typical examples of DNA methylation data analysis in cancer research and diagnostics: the classification of tumour tissue samples, the detection of cancer in plasma samples, and the tissue based prediction of tumour recurrence.
Yosef Grodzinsky and Katrin Amunts (eds)
- Published in print:
- 2006
- Published Online:
- May 2009
- ISBN:
- 9780195177640
- eISBN:
- 9780199864799
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195177640.001.0001
- Subject:
- Neuroscience, Sensory and Motor Systems, Behavioral Neuroscience
Broca's region has been in the news ever since scientists realized that particular cognitive functions could be localized to parts of the cerebral cortex. Its discoverer, Paul Broca, was one of the ...
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Broca's region has been in the news ever since scientists realized that particular cognitive functions could be localized to parts of the cerebral cortex. Its discoverer, Paul Broca, was one of the first researchers to argue for a direct connection between a concrete behavior—in this case, the use of language—and a specific cortical region. Today, Broca's region is perhaps the most famous part of the human brain, and for over a century, has persisted as the focus of intense research and numerous debates. The name has even penetrated mainstream culture through popular science and the theater. Broca's region is famous for a good reason: As language is one of the most distinctive human traits, the cognitive mechanisms that support it and the tissues in which these mechanisms are housed are also quite complex, and so have the potential to reveal a lot not only about how words, phrases, sentences, and grammatical rules are instantiated in neural tissue, but also, and more broadly, about how brain function relates to behavior. Paul Broca's discoveries were an important, driving force behind the more general effort to relate complex behavior to particular parts of the cerebral cortex, which, significantly, produced the first brain maps.Less
Broca's region has been in the news ever since scientists realized that particular cognitive functions could be localized to parts of the cerebral cortex. Its discoverer, Paul Broca, was one of the first researchers to argue for a direct connection between a concrete behavior—in this case, the use of language—and a specific cortical region. Today, Broca's region is perhaps the most famous part of the human brain, and for over a century, has persisted as the focus of intense research and numerous debates. The name has even penetrated mainstream culture through popular science and the theater. Broca's region is famous for a good reason: As language is one of the most distinctive human traits, the cognitive mechanisms that support it and the tissues in which these mechanisms are housed are also quite complex, and so have the potential to reveal a lot not only about how words, phrases, sentences, and grammatical rules are instantiated in neural tissue, but also, and more broadly, about how brain function relates to behavior. Paul Broca's discoveries were an important, driving force behind the more general effort to relate complex behavior to particular parts of the cerebral cortex, which, significantly, produced the first brain maps.
Bente Finsen, Rikke Gregersen, Elin Lehrmann, Steen Lovmand, and Mark J. West
- Published in print:
- 2004
- Published Online:
- September 2009
- ISBN:
- 9780198505280
- eISBN:
- 9780191723766
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198505280.003.0005
- Subject:
- Neuroscience, Techniques
This chapter discusses in situ hybridization. Topics covered include the principles of hybridization, visualization of single cells with AP-conjugated oligonucleotide probes, sensitivity of alkaline ...
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This chapter discusses in situ hybridization. Topics covered include the principles of hybridization, visualization of single cells with AP-conjugated oligonucleotide probes, sensitivity of alkaline phosphatase (AP)-labeled, tissue processing, specificity of the hybridization reaction, screening of internal standard sections, and stereological quantification.Less
This chapter discusses in situ hybridization. Topics covered include the principles of hybridization, visualization of single cells with AP-conjugated oligonucleotide probes, sensitivity of alkaline phosphatase (AP)-labeled, tissue processing, specificity of the hybridization reaction, screening of internal standard sections, and stereological quantification.
Peter Hoskin and Wendy Makin
- Published in print:
- 2003
- Published Online:
- November 2011
- ISBN:
- 9780192628114
- eISBN:
- 9780191730115
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780192628114.003.0018
- Subject:
- Palliative Care, Patient Care and End-of-Life Decision Making, Pain Management and Palliative Pharmacology
This chapter discusses tumours and malignancies occurring in the bones and soft tissues. These are common in children and rare in adults. Bone and soft tissue tumours may occur at any age; however, ...
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This chapter discusses tumours and malignancies occurring in the bones and soft tissues. These are common in children and rare in adults. Bone and soft tissue tumours may occur at any age; however, certain types of tumour follow a recognized pattern. Bone and soft tissue tumours grow and infiltrate locally, and they commonly affect the lungs via blood-borne metastasis. These tumours have great implications for the extent of local treatment required and the probability of local recurrence. Topics covered are the common symptoms associated with these tumours, such as pain, fungation and haemorrhage, as well as the management and treatment procedures that alleviate these.Less
This chapter discusses tumours and malignancies occurring in the bones and soft tissues. These are common in children and rare in adults. Bone and soft tissue tumours may occur at any age; however, certain types of tumour follow a recognized pattern. Bone and soft tissue tumours grow and infiltrate locally, and they commonly affect the lungs via blood-borne metastasis. These tumours have great implications for the extent of local treatment required and the probability of local recurrence. Topics covered are the common symptoms associated with these tumours, such as pain, fungation and haemorrhage, as well as the management and treatment procedures that alleviate these.
G. A. D. Briggs and O. V. Kolosov
- Published in print:
- 2009
- Published Online:
- February 2010
- ISBN:
- 9780199232734
- eISBN:
- 9780191716355
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199232734.003.0009
- Subject:
- Physics, Condensed Matter Physics / Materials
Biological tissue: The elastic properties of biological tissue show much greater contrast than their optical properties. Cells can be imaged in an aqueous medium, so that the ...
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Biological tissue: The elastic properties of biological tissue show much greater contrast than their optical properties. Cells can be imaged in an aqueous medium, so that the variation with environment and time of their mechanical properties and adhesion to a substrate can be measured. For soft tissue, time‐resolved techniques are more relevant than Rayleigh wave interference. Mineralized tissues such as teeth can support Rayleigh waves, giving contrast from carious lesions and allowing line‐focus‐beam V(z) analysis to measure elastic anisotropy. Bone is an intermediate case, with contrast from its mechanical structure.Less
Biological tissue: The elastic properties of biological tissue show much greater contrast than their optical properties. Cells can be imaged in an aqueous medium, so that the variation with environment and time of their mechanical properties and adhesion to a substrate can be measured. For soft tissue, time‐resolved techniques are more relevant than Rayleigh wave interference. Mineralized tissues such as teeth can support Rayleigh waves, giving contrast from carious lesions and allowing line‐focus‐beam V(z) analysis to measure elastic anisotropy. Bone is an intermediate case, with contrast from its mechanical structure.
Paul L. Nunez and Ramesh Srinivasan
- Published in print:
- 2006
- Published Online:
- May 2009
- ISBN:
- 9780195050387
- eISBN:
- 9780199865673
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195050387.003.0004
- Subject:
- Neuroscience, Neuroendocrine and Autonomic, Techniques
This chapter continues the physical principles of Chapter 3 in the context of biological tissue. Electrophysiology spans about five orders of magnitude of spatial scale, ranging from the ...
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This chapter continues the physical principles of Chapter 3 in the context of biological tissue. Electrophysiology spans about five orders of magnitude of spatial scale, ranging from the microelectrode recordings of transmembrane potentials to millimeter-scale intracranial recordings to centimeter-scale scalp potentials. The classic membrane diffusion equation (core conductor model) is derived from basic principles without reference to any “equivalent circuit.” Tissue electrical properties at several scales are considered with emphasis on the cortical and skull tissues. A volume (current) microsource function and a millimeter scale (current) source function P(r,t) are defined based on fundamental physical and physiological principles. A low-pass filtering effect on cortical potentials is predicted based on reduced (pyramidal cell) microsource/sink separations in cortex at frequencies of perhaps 50 to 100 Hz. The relationship of P(r,t) to scalp potentials is discussed in the context of a Green's function for the head volume conductor, providing equivalent “electrical distances” between sources and scalp electrodes.Less
This chapter continues the physical principles of Chapter 3 in the context of biological tissue. Electrophysiology spans about five orders of magnitude of spatial scale, ranging from the microelectrode recordings of transmembrane potentials to millimeter-scale intracranial recordings to centimeter-scale scalp potentials. The classic membrane diffusion equation (core conductor model) is derived from basic principles without reference to any “equivalent circuit.” Tissue electrical properties at several scales are considered with emphasis on the cortical and skull tissues. A volume (current) microsource function and a millimeter scale (current) source function P(r,t) are defined based on fundamental physical and physiological principles. A low-pass filtering effect on cortical potentials is predicted based on reduced (pyramidal cell) microsource/sink separations in cortex at frequencies of perhaps 50 to 100 Hz. The relationship of P(r,t) to scalp potentials is discussed in the context of a Green's function for the head volume conductor, providing equivalent “electrical distances” between sources and scalp electrodes.
NAOMI KLEITMAN and RICHARD P. BUNGE
- Published in print:
- 1995
- Published Online:
- May 2009
- ISBN:
- 9780195082937
- eISBN:
- 9780199865802
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195082937.003.0005
- Subject:
- Neuroscience, Disorders of the Nervous System
This chapter describes the sequential phenomena observed during the development of the peripheral nerve, with emphasis on the Schwann cell. It presents research elucidating the mechanisms by which ...
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This chapter describes the sequential phenomena observed during the development of the peripheral nerve, with emphasis on the Schwann cell. It presents research elucidating the mechanisms by which these phenomena are controlled. The use of tissue culture models of nerve development is emphasized inasmuch as these have contributed greatly to the understanding of the role of each of the peripheral nerve cell types at each stage of differentiation. The chapter reviews how these studies have elucidated the interactions that create the fully functional nerve. Finally, it discusses ways in which understanding these cellular interactions may be exploited to maximize regeneration in the wake of injury.Less
This chapter describes the sequential phenomena observed during the development of the peripheral nerve, with emphasis on the Schwann cell. It presents research elucidating the mechanisms by which these phenomena are controlled. The use of tissue culture models of nerve development is emphasized inasmuch as these have contributed greatly to the understanding of the role of each of the peripheral nerve cell types at each stage of differentiation. The chapter reviews how these studies have elucidated the interactions that create the fully functional nerve. Finally, it discusses ways in which understanding these cellular interactions may be exploited to maximize regeneration in the wake of injury.
Francesca Aloisi
- Published in print:
- 2004
- Published Online:
- May 2009
- ISBN:
- 9780195152227
- eISBN:
- 9780199865024
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195152227.003.0022
- Subject:
- Neuroscience, Development, Disorders of the Nervous System
This chapter discusses recent research on cytokines that are produced by and/or act on glial cells, focusing on those involved in the regulation of inflammatory, immune, and tissue repair processes. ...
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This chapter discusses recent research on cytokines that are produced by and/or act on glial cells, focusing on those involved in the regulation of inflammatory, immune, and tissue repair processes. It shows that the maintenance of tissue homeostasis and responses to pathological stimuli in the nervous system are governed by the integrated action of multiple cytokines, most of which appear to be produced by glial cells. Although each glial cell type has the potential to express various cytokines, it is the kind of stimulus that dictates the temporal and cellular cascade of cytokine expression that is initiated under a given condition. Recent studies in transgenic and knockout mice have show that several glia-derived cytokines, such as IL-1, TNF and IL-6, may subserve both neuroinflammatory and neuroprotective functions.Less
This chapter discusses recent research on cytokines that are produced by and/or act on glial cells, focusing on those involved in the regulation of inflammatory, immune, and tissue repair processes. It shows that the maintenance of tissue homeostasis and responses to pathological stimuli in the nervous system are governed by the integrated action of multiple cytokines, most of which appear to be produced by glial cells. Although each glial cell type has the potential to express various cytokines, it is the kind of stimulus that dictates the temporal and cellular cascade of cytokine expression that is initiated under a given condition. Recent studies in transgenic and knockout mice have show that several glia-derived cytokines, such as IL-1, TNF and IL-6, may subserve both neuroinflammatory and neuroprotective functions.
Håkan Widner
- Published in print:
- 2002
- Published Online:
- March 2012
- ISBN:
- 9780198509806
- eISBN:
- 9780191724596
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198509806.003.0011
- Subject:
- Neuroscience, Disorders of the Nervous System
This chapter examines the factors that must be considered in the transplantation of neuronal and non-neuronal tissue into the brain parenchyma for repair and neuroprotective purposes. It discusses ...
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This chapter examines the factors that must be considered in the transplantation of neuronal and non-neuronal tissue into the brain parenchyma for repair and neuroprotective purposes. It discusses the afferent pathways from the brain to the immune system and immunological responses against intracerebral neural allografts. The chapter suggests that immune responses need to be addressed in any protocol for transplantation of tissue and cells into the brain for a successful outcome.Less
This chapter examines the factors that must be considered in the transplantation of neuronal and non-neuronal tissue into the brain parenchyma for repair and neuroprotective purposes. It discusses the afferent pathways from the brain to the immune system and immunological responses against intracerebral neural allografts. The chapter suggests that immune responses need to be addressed in any protocol for transplantation of tissue and cells into the brain for a successful outcome.
Jerome O. Nriagu
- Published in print:
- 2015
- Published Online:
- May 2016
- ISBN:
- 9780262029193
- eISBN:
- 9780262327619
- Item type:
- chapter
- Publisher:
- The MIT Press
- DOI:
- 10.7551/mitpress/9780262029193.003.0012
- Subject:
- Public Health and Epidemiology, Public Health
Trace metals are required in small quantities for a wide array of metabolic functions in the body. In terms of obesity, they can enhance insulin action through activating insulin receptor sites, ...
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Trace metals are required in small quantities for a wide array of metabolic functions in the body. In terms of obesity, they can enhance insulin action through activating insulin receptor sites, serve as cofactors or components for enzyme systems involved in glucose metabolism, increase insulin sensitivity, and act as antioxidants to prevent tissue oxidation. Chronic hyperglycemia causes significant alterations in the status of many trace metals in the body and consequently increases the oxidative stress which can contribute to the pathogenesis of infectious diseases. Whether obese individuals with trace metal deficiency (or toxicity) are at increased risk for infection is a matter of concern in many developing countries, where a growing segment of the population (exposed to traditional health risks) has embraced Western dietary habits. A better understanding of the roles of different trace metals will undoubtedly facilitate the development of new treatment and prevention strategies that can more effectively reduce the silent burden of comorbid obesity and infectious diseases.Less
Trace metals are required in small quantities for a wide array of metabolic functions in the body. In terms of obesity, they can enhance insulin action through activating insulin receptor sites, serve as cofactors or components for enzyme systems involved in glucose metabolism, increase insulin sensitivity, and act as antioxidants to prevent tissue oxidation. Chronic hyperglycemia causes significant alterations in the status of many trace metals in the body and consequently increases the oxidative stress which can contribute to the pathogenesis of infectious diseases. Whether obese individuals with trace metal deficiency (or toxicity) are at increased risk for infection is a matter of concern in many developing countries, where a growing segment of the population (exposed to traditional health risks) has embraced Western dietary habits. A better understanding of the roles of different trace metals will undoubtedly facilitate the development of new treatment and prevention strategies that can more effectively reduce the silent burden of comorbid obesity and infectious diseases.
Scott Curtis
- Published in print:
- 2015
- Published Online:
- May 2016
- ISBN:
- 9780231134033
- eISBN:
- 9780231508636
- Item type:
- chapter
- Publisher:
- Columbia University Press
- DOI:
- 10.7312/columbia/9780231134033.003.0002
- Subject:
- Film, Television and Radio, Film
Chapter One examines use of film as a scientific research tool in three fields (human motion studies, physics, biology) in Germany from the 1880s to 1914. It argues that there is a close relationship ...
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Chapter One examines use of film as a scientific research tool in three fields (human motion studies, physics, biology) in Germany from the 1880s to 1914. It argues that there is a close relationship between film form and disciplinary agendas, which explains the affinity between cinema and science that Henri Bergson critiqued in Creative Evolution (1907).Less
Chapter One examines use of film as a scientific research tool in three fields (human motion studies, physics, biology) in Germany from the 1880s to 1914. It argues that there is a close relationship between film form and disciplinary agendas, which explains the affinity between cinema and science that Henri Bergson critiqued in Creative Evolution (1907).
