title: The PIN-domain ribonucleases and the prokaryotic VapBC toxin–antitoxin array

authors: Arcus, Vickery L.

subjects: growth regulation

abstract: The PIN-domains are small proteins of ∼130 amino acids that are found in bacteria, archaea and eukaryotes and are defined by a group of three strictly conserved acidic amino acids. The conserved three-dimensional structures of the PIN-domains cluster these acidic residues in an enzymatic active site. PIN-domains cleave single-stranded RNA in a sequence-specific, Mg²⁺- or Mg²⁺- dependent manner. These ribonucleases are toxic to the cells which express them and to offset this toxicity, they are co-expressed with tight binding protein inhibitors. The genes encoding these two proteins are adjacent in the genome of all prokaryotic organisms where they are found. This sequential arrangement of inhibitor-RNAse genes conforms to that of the so-called toxin–antitoxin (TA) modules and the PIN-domain TAs have been named VapBC TAs (virulence associated proteins, VapB is the inhibitor which contains a transcription factor domain and VapC is the PIN-domain ribonuclease). The presence of large numbers of vapBC loci in disparate prokaryotes has motivated many researchers to investigate their biochemical and biological functions. For example, the devastating human pathogen Mycobacterium tuberculosis has 45 vapBC loci encoded in its genome whereas its non-pathogenic relative, Mycobacterium smegmatis has just one vapBC operon. On another branch of the prokaryotic tree, the nitrogen-fixing symbiont of legumes, Sinorhizobium meliloti has 21 vapBC loci and at least one of these loci have been implicated in the regulation of growth in the plant nodule. A range of biological functions has been suggested for these operons and this review sets out to survey the PIN-domains and summarise the current knowledge about the vapBC TA systems and their roles in diverse bacteria.

text: The PIN-domain ribonucleases and the prokaryotic VapBC toxin–antitoxin array The PIN-domains are small proteins of ∼130 amino acids that are found in bacteria, archaea and eukaryotes and are defined by a group of three strictly conserved acidic amino acids. The conserved three-dimensional structures of the PIN-domains cluster these acidic residues in an enzymatic active site. PIN-domains cleave single-stranded RNA in a sequence-specific, Mg²⁺- or Mg²⁺- dependent manner. These ribonucleases are toxic to the cells which express them and to offset this toxicity, they are co-expressed with tight binding protein inhibitors. The genes encoding these two proteins are adjacent in the genome of all prokaryotic organisms where they are found. This sequential arrangement of inhibitor-RNAse genes conforms to that of the so-called toxin–antitoxin (TA) modules and the PIN-domain TAs have been named VapBC TAs (virulence associated proteins, VapB is the inhibitor which contains a transcription factor domain and VapC is the PIN-domain ribonuclease). The presence of large numbers of vapBC loci in disparate prokaryotes has motivated many researchers to investigate their biochemical and biological functions. For example, the devastating human pathogen Mycobacterium tuberculosis has 45 vapBC loci encoded in its genome whereas its non-pathogenic relative, Mycobacterium smegmatis has just one vapBC operon. On another branch of the prokaryotic tree, the nitrogen-fixing symbiont of legumes, Sinorhizobium meliloti has 21 vapBC loci and at least one of these loci have been implicated in the regulation of growth in the plant nodule. A range of biological functions has been suggested for these operons and this review sets out to survey the PIN-domains and summarise the current knowledge about the vapBC TA systems and their roles in diverse bacteria.

year: 2010

title: New Zealand jobs, 1976 - 1996: A demographic accounting

authors: Honey, Jeff

subjects: population

abstract: Over the last decade or so New Zealand has been through an era of radical political, economic, social and demographic change. In part this has been driven by economic restructuring. But in part, this had been an acceleration of a long-term industrial transformation, which had been a part of New Zealand culture for some time (Thompson 1985). This has taken the form of a long-term shift of employment out of the secondary sector and into the tertiary sector industries. Moreover, in the post-war period there has been a gradual further decline in the proportion of jobs in the primary sectors despite continuous economic improvements of agricultural activities. This is demonstrated proportionately more in terms of its contribution to exports and to the distribution of Gross Domestic Production across sectors, than in high percentages of the labour force in the primary sector. In this and other ways, New Zealand has been subject to the structural changes experienced by other developed countries. The major difference has been the speed of the policy-driven restructuring over the last decade in New Zealand.

This paper turns to some basic accounting methods to analyse increases and decreases in job numbers by industrial sector between 1976 and 1996. Analysis by gender, ethnicity and broad age groups will provide a more detailed picture of the major movements. Secondly, in order to assess whether there are gaps between employment and supply, these increases and decreases will be compared with data which indicate levels of "demographic supply". These data give, as it were, an "expected" figure for change in the numbers in each category. and this can be compared with the "observed" figures.

Demographic supply is defined here as the percentage growth between the periods analysed in the population at working ages (15-64 years). This paper also looks at the proportionate shifts between censuses in the number of workers by age, gender and ethnicity in a particular industry or broad sector. This analysis is strengthened by comparing the observed "gains and losses" which might have been expected through natural growth and attrition. What these data imply, therefore, is whether or not the labour market is dysfunctional in the way it can respond to a combination of gains and losses because of under- and over-supply of workers, plus the absorptive capacity of a given segment of the labour market.

text: New Zealand jobs, 1976 - 1996: A demographic accounting Over the last decade or so New Zealand has been through an era of radical political, economic, social and demographic change. In part this has been driven by economic restructuring. But in part, this had been an acceleration of a long-term industrial transformation, which had been a part of New Zealand culture for some time (Thompson 1985). This has taken the form of a long-term shift of employment out of the secondary sector and into the tertiary sector industries. Moreover, in the post-war period there has been a gradual further decline in the proportion of jobs in the primary sectors despite continuous economic improvements of agricultural activities. This is demonstrated proportionately more in terms of its contribution to exports and to the distribution of Gross Domestic Production across sectors, than in high percentages of the labour force in the primary sector. In this and other ways, New Zealand has been subject to the structural changes experienced by other developed countries. The major difference has been the speed of the policy-driven restructuring over the last decade in New Zealand.

This paper turns to some basic accounting methods to analyse increases and decreases in job numbers by industrial sector between 1976 and 1996. Analysis by gender, ethnicity and broad age groups will provide a more detailed picture of the major movements. Secondly, in order to assess whether there are gaps between employment and supply, these increases and decreases will be compared with data which indicate levels of "demographic supply". These data give, as it were, an "expected" figure for change in the numbers in each category. and this can be compared with the "observed" figures.

Demographic supply is defined here as the percentage growth between the periods analysed in the population at working ages (15-64 years). This paper also looks at the proportionate shifts between censuses in the number of workers by age, gender and ethnicity in a particular industry or broad sector. This analysis is strengthened by comparing the observed "gains and losses" which might have been expected through natural growth and attrition. What these data imply, therefore, is whether or not the labour market is dysfunctional in the way it can respond to a combination of gains and losses because of under- and over-supply of workers, plus the absorptive capacity of a given segment of the labour market.

year: 2001-09

title: What a difference a default setting makes

authors: Keegan, Te Taka Adrian Gregory

subjects: computer science

abstract: This paper examines the effect of the default interface language on the usage of a bilingual digital library. In 2005 the default interface language of a bilingual digital library was alternated on a monthly basis between Māori and English. A comprehensive transaction log analysis over this period reveals that not only did usage in a particular language increase when the default interface language was set to that language but that the way the interface was used, in both languages, was quite different depending on the default language.

text: What a difference a default setting makes This paper examines the effect of the default interface language on the usage of a bilingual digital library. In 2005 the default interface language of a bilingual digital library was alternated on a monthly basis between Māori and English. A comprehensive transaction log analysis over this period reveals that not only did usage in a particular language increase when the default interface language was set to that language but that the way the interface was used, in both languages, was quite different depending on the default language.

year: 2008