ProxiMAX randomisation:a new technology for non-degenerate saturation mutagenesis of contiguous codons

Back in 2003, we published ‘MAX’ randomisation, a process of non-degenerate saturation mutagenesis using exactly 20 codons (one for each amino acid) or else any required subset of those 20 codons. ‘MAX’ randomisation saturates codons located in isolated positions within a protein, as might be required in enzyme engineering, or else on one face of an alpha-helix, as in zinc finger engineering. Since that time, we have been asked for an equivalent process that can saturate multiple, contiguous codons in a non-degenerate manner. We have now developed ‘ProxiMAX’ randomisation, which does just that: generating DNA cassettes for saturation mutagenesis without degeneracy or bias. Offering an alternative to trinucleotide phosphoramidite chemistry, ProxiMAX randomisation uses nothing more sophisticated than unmodified oligonucleotides and standard molecular biology reagents. Thus it requires no specialised chemistry, reagents nor equipment and simply relies on a process of saturation cycling comprising ligation, amplification and digestion for each cycle. The process can encode both unbiased representation of selected amino acids or else encode them in pre-defined ratios. Each saturated position can be defined independently of the others. We demonstrate accurate saturation of up to 11 contiguous codons. As such, ProxiMAX randomisation is particularly relevant to antibody engineering

An Analysis of Merit Pay Reforms in Educational Institutions

With roots in behaviorist philosophy, performance pay for teachers is often linked to accountability regimes in school reform. The theory girding such programs suggests that pay as an economic incentive can help cause teachers to increase student outcomes as measured by standardized test scores. What is little noticed by many educationists, but particularly by policy makers, is how programmatic effects affect the ontology of educational environment. There are several ways to approach the viability of such programs. In this study of three pay-for-performance programs, two in the U.S. and one in the UK, we provide theoretic insights in light of three variables: (i) their psychological framework, (ii) teacher efficacy and the teacher-student relationship, and (iii) how the psychological impact of such programs coincides with larger institutional forces. Using theory to examine pay-for-performance is necessary in order to get beneath mere data and secure more thorough understandings of the phenomenological impacts of performance pay. And better understanding of these foundational features is necessary, even critical, in order to fully appreciate the economic and informational trade-offs in implementation. Our study suggests that as a small-scale reform measure and when it specifically accounts for complexities of educational production, performance pay may be a viable reform option

An Analysis of Merit Pay Reforms in Educational Institutions

With roots in behaviorist philosophy, performance pay for teachers is often linked to accountability regimes in school reform. The theory girding such programs suggests that pay as an economic incentive can help cause teachers to increase student outcomes as measured by standardized test scores. What is little noticed by many educationists, but particularly by policy makers, is how programmatic effects affect the ontology of educational environment. There are several ways to approach the viability of such programs. In this study of three pay-for-performance programs, two in the U.S. and one in the UK, we provide theoretic insights in light of three variables: (i) their psychological framework, (ii) teacher efficacy and the teacher-student relationship, and (iii) how the psychological impact of such programs coincides with larger institutional forces. Using theory to examine pay-for-performance is necessary in order to get beneath mere data and secure more thorough understandings of the phenomenological impacts of performance pay. And better understanding of these foundational features is necessary, even critical, in order to fully appreciate the economic and informational trade-offs in implementation. Our study suggests that as a small-scale reform measure and when it specifically accounts for complexities of educational production, performance pay may be a viable reform option.education, policy

Transcriptomic underpinning of toxicant-mediated physiological function alterations in three terrestrial invertebrate taxa: A review.

Diverse anthropogenic activities often lead to the accumulation of inorganic and organic residues in topsoils. Biota living in close contact with contaminated soils may experience stress at different levels of biological organisation throughout the continuum from the molecular-genetic to ecological and community levels. To date, the relationship between changes at the molecular (mRNA expression) and biochemical/physiological levels evoked by exposures to chemical compounds has been partially established in a limited number of terrestrial invertebrate species. Recently, the advent of a family of transcriptomic tools (e.g. Real-time PCR, Subtractive Suppressive Hybridization, Expressed Sequence Tag sequencing, pyro-sequencing technologies, Microarray chips), together with supporting informatic and statistical procedures, have permitted the robust analyses of global gene expression changes within an ecotoxicological context. This review focuses on how transcriptomics is enlightening our understanding of the molecular-genetic responses of three contrasting terrestrial macroinvertebrate taxa (nematodes, earthworms, and springtails) to inorganics, organics, and agrochemicals