title: Review: Biomolecular stability and life at high temperatures

authors: Daniel, Roy M.

subjects: archaea

abstract: It is not clear what the upper temperature limit forlife is, or what specific factors will set this limit, but it is generally assumed that the limit will be dictated by molecular instability. In this review, we examine the thermal stability of two key groups of biological molecules: the intracellular small molecules/metabolites and the major classes of macromolecules. Certain small molecules/metabolites are unstable in vitro at the growth temperatures of the hyperthermophiles in which they are found. This instability appears to be dealt with in vivo by a range of mechanisms including rapid turnover, metabolic channelling and local stabilisation. Evidence to date suggests that proteins have the potential to be stable at substantially higher temperatures than those known to support life, but evidence concerning degradative reactions above 100p°C is slight. DNA duplex stability is apparently achieved at high temperature by elevated salt concentrations, polyamines, cationic proteins, and supercoiling rather than manipulation of C-G ratios. RNA stability seems dependent upon covalent modification, although secondary structure is probably also critical. The diether-linked lipids, which make up the monolayer membrane of most organisms growing above 85p°C are chemically very stable and seem potentially capable of maintaining membrane integrity at much higher temperatures. However, the in vivo implications of the in vitro instability of biomolecules are difficult to assess, and in vivo data are rare.

text: Review: Biomolecular stability and life at high temperatures It is not clear what the upper temperature limit forlife is, or what specific factors will set this limit, but it is generally assumed that the limit will be dictated by molecular instability. In this review, we examine the thermal stability of two key groups of biological molecules: the intracellular small molecules/metabolites and the major classes of macromolecules. Certain small molecules/metabolites are unstable in vitro at the growth temperatures of the hyperthermophiles in which they are found. This instability appears to be dealt with in vivo by a range of mechanisms including rapid turnover, metabolic channelling and local stabilisation. Evidence to date suggests that proteins have the potential to be stable at substantially higher temperatures than those known to support life, but evidence concerning degradative reactions above 100p°C is slight. DNA duplex stability is apparently achieved at high temperature by elevated salt concentrations, polyamines, cationic proteins, and supercoiling rather than manipulation of C-G ratios. RNA stability seems dependent upon covalent modification, although secondary structure is probably also critical. The diether-linked lipids, which make up the monolayer membrane of most organisms growing above 85p°C are chemically very stable and seem potentially capable of maintaining membrane integrity at much higher temperatures. However, the in vivo implications of the in vitro instability of biomolecules are difficult to assess, and in vivo data are rare.

year: 2000

title: Social conceptions versus legal protections of privacy and information security in the context of encryption

authors: Dizon, Michael

abstract: This article examines the disconnect between people’s social conceptions of privacy and information security in relation to encryption vis-à-vis the legal protections offered by law. It describes the social conceptions and expectations of participants based in New Zealand and contrasts these with the applicable laws and legal protections concerning privacy, information security and encryption. In light of incongruence between the social and the legal, the article recommends law and policy developments to better align and connect people’s social conceptions of privacy and information security with the legal protections provided by law. This includes having greater awareness of the relevance of civil and criminal procedure rights to privacy and information security in the context of encryption and providing stronger legal protections to the right against unreasonable search and seizure and the privilege against self-incrimination.

text: Social conceptions versus legal protections of privacy and information security in the context of encryption This article examines the disconnect between people’s social conceptions of privacy and information security in relation to encryption vis-à-vis the legal protections offered by law. It describes the social conceptions and expectations of participants based in New Zealand and contrasts these with the applicable laws and legal protections concerning privacy, information security and encryption. In light of incongruence between the social and the legal, the article recommends law and policy developments to better align and connect people’s social conceptions of privacy and information security with the legal protections provided by law. This includes having greater awareness of the relevance of civil and criminal procedure rights to privacy and information security in the context of encryption and providing stronger legal protections to the right against unreasonable search and seizure and the privilege against self-incrimination.

year: 2022

title: Ka awatea

authors: Levy, Michelle Patricia

abstract: This book realises a long held vision to boldly claim our space in psychology: showing how we as Māori practitioners, researchers, and teachers of psychology realise our belief in the potential of psychology to contribute positively to the lives of our whānau. Celebrating our diversity, while at the same time being drawn together by our commonalities, these pages offer a space where all our contributions can be honoured. Our title, originating from Virginia’s chapter, which in turn originated from a well-known whakataukī, expresses the distinctiveness and beauty of manu Māori who herald the dawn, share stories and who listen to the voices of the universe. Like the manu, our reo expresses our whakaaro and our shared beginnings that unite and connect us across the dimensions of wairua, land, sea and air.

text: Ka awatea This book realises a long held vision to boldly claim our space in psychology: showing how we as Māori practitioners, researchers, and teachers of psychology realise our belief in the potential of psychology to contribute positively to the lives of our whānau. Celebrating our diversity, while at the same time being drawn together by our commonalities, these pages offer a space where all our contributions can be honoured. Our title, originating from Virginia’s chapter, which in turn originated from a well-known whakataukī, expresses the distinctiveness and beauty of manu Māori who herald the dawn, share stories and who listen to the voices of the universe. Like the manu, our reo expresses our whakaaro and our shared beginnings that unite and connect us across the dimensions of wairua, land, sea and air.

year: 2016