title: Molecular dynamics decomposition of temperature-dependent elastic neutron scattering by a protein solution

authors: Hayward, Jennifer A.

abstract: Molecular dynamics simulations are performed of bovine pancreatic trypsin inhibitor in a cryosolution over a range of temperatures from 80 to 300 K and the origins identified of elastic dynamic neutron scattering from the solution. The elastic scattering and mean-square displacement calculated from the molecular dynamics trajectories are in reasonable agreement with experiments on a larger protein in the same solvent. The solvent and protein contributions to the scattering from the simulation model are determined. At lower temperatures (< 200 K) or on shorter timescales ( 10 ps) the scattering contributions are proportional to the isotopic nuclear scattering cross-sections of each component. However, for T > 200 K marked deviations from these cross-sections are seen due to differences in the dynamics of the components of the solution. Rapid activation of solvent diffusion leads to the variation with temperature of the total elastic intensity being determined largely by that of the solvent. At higher temperatures (>240 K) and longer times ( 100 ps) the protein makes the only significant contribution to the scattering, the solvent scattering having moved out of the accessible time-space window. Decomposition of the protein mean-square displacement shows that the observed dynamical transition in the solution at 200–220 K involves activation of both internal motions and external whole-molecule rotational and translational diffusion. The proportion that the external dynamics contributes to the protein mean-square displacement increases to  30 and 60% at 300 K on the 10- and 100-ps timescales, respectively.

text: Molecular dynamics decomposition of temperature-dependent elastic neutron scattering by a protein solution Molecular dynamics simulations are performed of bovine pancreatic trypsin inhibitor in a cryosolution over a range of temperatures from 80 to 300 K and the origins identified of elastic dynamic neutron scattering from the solution. The elastic scattering and mean-square displacement calculated from the molecular dynamics trajectories are in reasonable agreement with experiments on a larger protein in the same solvent. The solvent and protein contributions to the scattering from the simulation model are determined. At lower temperatures (< 200 K) or on shorter timescales ( 10 ps) the scattering contributions are proportional to the isotopic nuclear scattering cross-sections of each component. However, for T > 200 K marked deviations from these cross-sections are seen due to differences in the dynamics of the components of the solution. Rapid activation of solvent diffusion leads to the variation with temperature of the total elastic intensity being determined largely by that of the solvent. At higher temperatures (>240 K) and longer times ( 100 ps) the protein makes the only significant contribution to the scattering, the solvent scattering having moved out of the accessible time-space window. Decomposition of the protein mean-square displacement shows that the observed dynamical transition in the solution at 200–220 K involves activation of both internal motions and external whole-molecule rotational and translational diffusion. The proportion that the external dynamics contributes to the protein mean-square displacement increases to  30 and 60% at 300 K on the 10- and 100-ps timescales, respectively.

year: 2003-08

title: David Bowie and the Art of Music Video

authors: Perrott, Lisa

subjects: Art

abstract: The first in-depth study of David Bowie's music videos across a sustained period takes on interweaving storyworlds of an iconic career. Remarkable for their capacity to conjure elaborate imagery, Bowie's videos provide fascinating exemplars of the artistry and remediation of music video. When their construction is examined across several years, they appear as time-travelling vessels, transporting kooky characters and strange story-world components across time and space. By charting Bowie's creative and collaborative process across five distinct phases, David Bowie and the Art of Music Video shows how he played a vital role in establishing music video as an artform. Filling a gap in the existing literature, this book shines a light on the significant contributions of directors such as Mick Rock, Stanley Dorfman and David Mallet, each of whom taught Bowie much about how to use the form. By examining Bowie's collaborative process, his use of surrealist strategies and his integration of avant-garde art with popular music and media, the book provides a history of music video in relation to the broader fields of audiovisual media, visual music and art.

text: David Bowie and the Art of Music Video The first in-depth study of David Bowie's music videos across a sustained period takes on interweaving storyworlds of an iconic career. Remarkable for their capacity to conjure elaborate imagery, Bowie's videos provide fascinating exemplars of the artistry and remediation of music video. When their construction is examined across several years, they appear as time-travelling vessels, transporting kooky characters and strange story-world components across time and space. By charting Bowie's creative and collaborative process across five distinct phases, David Bowie and the Art of Music Video shows how he played a vital role in establishing music video as an artform. Filling a gap in the existing literature, this book shines a light on the significant contributions of directors such as Mick Rock, Stanley Dorfman and David Mallet, each of whom taught Bowie much about how to use the form. By examining Bowie's collaborative process, his use of surrealist strategies and his integration of avant-garde art with popular music and media, the book provides a history of music video in relation to the broader fields of audiovisual media, visual music and art.

year: 2023-07-27

title: Indigenous perspectives and gene editing in Aotearoa New Zealand

authors: Hudson, Maui

subjects: Science & Technology

abstract: Gene editing is arguably the most significant recent addition to the modern biotechnology toolbox, bringing both profoundly challenging and enabling opportunities. From a technical point of view the specificity and relative simplicity of these new tools has broadened the potential applications. However, from an ethical point of view it has re-ignited the debates generated by earlier forms of genetic modification. In New Zealand gene editing is currently considered genetic modification and is subject to approval processes under the Environmental Protection Authority (EPA). This process requires decision makers to take into account Māori perspectives. This article outlines previously articulated Māori perspectives on genetic modification and considers the continuing influence of those cultural and ethical arguments within the new context of gene editing. It also explores the range of ways cultural values might be used to analyse the risks and benefits of gene editing in the Aotearoa New Zealand context. Methods used to obtain these perspectives consisted of (a) review of relevant literature regarding lessons learned from the responses of Maori to genetic modification, (b) interviews of selected ‘key Maori informants’ and (c) surveys of self-selected individuals from groups with interests in either genetics or environmental management. The outcomes of this pilot study identified that while Māori informants were not categorically opposed to new and emerging gene editing technologies a priori, they suggest a dynamic approach to regulation is required where specific uses or types of uses are approved on a case by case basis. This study demonstrates how the cultural cues that Māori referenced in the genetic modification debate continue to be relevant in the context of gene editing but that further work is required to characterize the strength of various positions across the broader community.

text: Indigenous perspectives and gene editing in Aotearoa New Zealand Gene editing is arguably the most significant recent addition to the modern biotechnology toolbox, bringing both profoundly challenging and enabling opportunities. From a technical point of view the specificity and relative simplicity of these new tools has broadened the potential applications. However, from an ethical point of view it has re-ignited the debates generated by earlier forms of genetic modification. In New Zealand gene editing is currently considered genetic modification and is subject to approval processes under the Environmental Protection Authority (EPA). This process requires decision makers to take into account Māori perspectives. This article outlines previously articulated Māori perspectives on genetic modification and considers the continuing influence of those cultural and ethical arguments within the new context of gene editing. It also explores the range of ways cultural values might be used to analyse the risks and benefits of gene editing in the Aotearoa New Zealand context. Methods used to obtain these perspectives consisted of (a) review of relevant literature regarding lessons learned from the responses of Maori to genetic modification, (b) interviews of selected ‘key Maori informants’ and (c) surveys of self-selected individuals from groups with interests in either genetics or environmental management. The outcomes of this pilot study identified that while Māori informants were not categorically opposed to new and emerging gene editing technologies a priori, they suggest a dynamic approach to regulation is required where specific uses or types of uses are approved on a case by case basis. This study demonstrates how the cultural cues that Māori referenced in the genetic modification debate continue to be relevant in the context of gene editing but that further work is required to characterize the strength of various positions across the broader community.

year: 2019