Metric Structure of the Space of Two-Qubit Gates, Perfect Entanglers and Quantum Control

We derive expressions for the invariant length element and measure for the simple compact Lie group SU(4) in a coordinate system particularly suitable for treating entanglement in quantum information processing. Using this metric, we compute the invariant volume of the space of two-qubit perfect entanglers. We find that this volume corresponds to more than 84% of the total invariant volume of the space of two-qubit gates. This same metric is also used to determine the effective target sizes that selected gates will present in any quantum-control procedure designed to implement them.Comment: 27 pages, 5 figure

A hierarchy of SPI activities for software SMEs: results from ISO/IEC 12207-based SPI assessments

In an assessment of software process improvement (SPI) in 15 software small- and –medium-sized enterprises (software SMEs), we applied the broad spectrum of software specific and system context processes in ISO/IEC 12207 to the task of examining SPI in practice. Using the data collected in the study, we developed a four-tiered pyramidal hierarchy of SPI for software SMEs, with processes in the higher tiers undergoing SPI in more companies than processes on lower level tiers. The development of the hierarchy of SPI activities for software SMEs can facilitate future evolutions of process maturity reference frameworks, such as ISO/IEC 15504, in better supporting software development in software SMEs. Furthermore, the findings extend our body of knowledge concerning the practice of SPI in software SMEs, a large and vital sector of the software development community that has largely avoided the implementation of established process maturity and software quality management standards

Antimicrobial antagonists against food pathogens; a bacteriocin perspective

peer-reviewedEfforts are continuing to find novel bacteriocins with enhanced specificity and potency. Traditional plating techniques are still being used for bacteriocin screening studies, however, the availability of ever more bacterial genome sequences and the use of in silico gene mining tools have revealed novel bacteriocin gene clusters that would otherwise have been overlooked. Furthermore, synthetic biology and bioengineering-based approaches are allowing scientists to harness existing and novel bacteriocin gene clusters through expression in different hosts and by enhancing functionalities. The same principles apply to bacteriocin producing probiotic cultures and their application to control pathogens in the gut. We can expect that the recent developments on bacteriocins from Lactic Acid Bacteria (LAB) described here will contribute greatly to increased commercialisation of bacteriocins in food systems.This work was funded by the Alimentary Pharmabiotic Centre, a research centre funded by Science Foundation Ireland (SFI), through the Irish Government’s National Development Plan. The authors and their work were supported by SFI (grant no. 12/RC/2273

In Vitro Activities of Nisin and Nisin Derivatives Alone and In Combination with Antibiotics against Staphylococcus Biofilms

peer-reviewedThe development and spread of pathogenic bacteria that are resistant to the existing catalog of antibiotics is a major public health threat. Biofilms are complex, sessile communities of bacteria embedded in an organic polymer matrix which serve to further enhance antimicrobial resistance. Consequently, novel compounds and innovative methods are urgently required to arrest the proliferation of drug-resistant infections in both nosocomial and community environments. Accordingly, it has been suggested that antimicrobial peptides could be used as novel natural inhibitors that can be used in formulations with synergistically acting antibiotics. Nisin is a member of the lantibiotic family of antimicrobial peptides that exhibit potent antibacterial activity against many Gram-positive bacteria. Recently we have used bioengineering strategies to enhance the activity of nisin against several high profile targets, including multi-drug resistant clinical pathogens such as methicillin-resistant Staphylococcus aureus, vancomycinresistant enterococci, staphylococci, and streptococci associated with bovine mastitis. We have also identified nisin derivatives with an enhanced ability to impair biofilm formation and to reduce the density of established biofilms of methicillin resistant S. pseudintermedius. The present study was aimed at evaluating the potential of nisin and nisin derivatives to increase the efficacy of conventional antibiotics and to assess the possibility of killing and/or eradicating biofilm-associated cells of a variety of staphylococcal targets. Growth curve-based comparisons established that combinations of derivatives nisin V C penicillin or nisin I4V C chloramphenicol had an enhanced inhibitory effect against S. aureus SA113 and S. pseudintermedius DSM21284, respectively, compared to the equivalent nisin A C antibiotic combinations or when each antimicrobial was administered alone. Furthermore, the metabolic activity of established biofilms treated with nisin V C chloramphenicol and nisin I4V C chloramphenicol combinations revealed a significant decrease in S. aureus SA113 and S. pseudintermedius DSM21284 biofilm viability, respectively, compared to the nisin A C antibiotic combinations as determined by the rapid colorimetric XTT assay. The results indicate that the activities of the nisin derivative and antibiotic combinations represent a significant improvement over that of the wild-type nisin and antibiotic combination and merit further investigation with a view to their use as anti-biofilm agents.DF,CH,PC,RR are supported by the Irish Government under the National Development Plan, through a Science Foundation Ireland (SFI)Technology and Innovation Development Award (TIDA14/TIDA/2286)to DF,a SFI Investigator awards to CH and RR(10/IN.1/B3027),SFI-PI funding(11/PI/1137)to PC and the Alimentary Pharmabiotic Centre under Grant Number SFI/12/RC/2273

The study of a prokaryotic glycolytic enzyme

The overall objective of this project is to generate novel carbohydrate binding proteins for use in glycoprotein analysis which are amenable to large scale production. The approach used here is the modification of prokaryotic glycolytic enzymes. Their enzymatic activity will be eliminated while hoping they still retain their binding capabilities. These proteins will be immobilized onto different surfaces to generate advanced bioanalytical platforms which will have huge commercial potential in the field of glycoanalysis

Evaluation of photografted charged sites within polymer monoliths in capillary columns using contactless conductivity detection

Capacitively coupled contactless conductivity detection (C4D) is presented as a novel and versatile means of visualising discrete zones of charged functional groups grafted onto polymer based monoliths. Monoliths were formed within 100 μm UV transparent fused silica capillaries and photografting methods were subsequently used to graft a charged functional monomer, 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) onto discrete regions of the “generic” monolith using a photomask. Post-modification monolith evaluation involves scanning the C4D detector along the length of the monolith to obtain a profile of the exact spatial location of grafted charged functionalities with millimetre accuracy. The methodology was extended to the visualisation of several zones of immobilised protein (bovine serum albumin) using photografted azlactone groups to enable covalent attachment of the protein to the monolith at precise locations along its length. In addition, the extent of non-specific binding of protein to the ungrafted regions of the monolith due to hydrophobic interactions could be monitored as an increase in background conductivity of the stationary phase. Finally, the technique was cross-validated using fluorescence microscopy by immobilising green fluorescent protein (GFP) in discrete zones and comparing the profiles obtained using both complementary techniques

Glycolytic enzymes - novel carbohydrate binding proteins for glycoprotein analysis

•The cloning, expression, purification and characterisation of recombinant prokaryotic glycolytic enzymes •The mutagenesis of prokaryotic glycolytic enzymes to generate novel recombinant carbohydrate binding proteins •The characterisation of the binding profile of the novel recombinant carbohydrate binding protein

The Policy, Process And Impact Of Whole School Inspection At Primary Level In The Republic Of Ireland From The Perspective Of Some Inspectors And Teachers

This thesis explores whole school inspection in the Republic of Ireland since its inception in 1976. It is located within the tradition of qualitative research and examines government policy. the process of inspecting and the impact of the operation on selected schools from the vantage point of participating inspectors and teachers. Ihe research is centred on three primary schools that underwent whole school inspection during the school year 1998-1999. A total of twenty teachers in all together with the three inspectors who conducted the inspections were interviewed immediately after the inspections, they were allowed a wide measure of freedom to express their views on the operation and their responses were analyzed. The senior management of the primary inspectorate was also interviewed and their views on official policy and on the efficacy of whole school inspection in general were elicited. The schools were revisited some six to nine months later and the teachers were once more interviewed in an effort to determine the level of impact made by the inspections and to gauge any change of view. What emerges is a lack of consensus among the key players on what constitutes the primary purpose of whole school inspection. In general the teachers saw it primarily as a surveillance exercise that generated high levels of anxiety, whereas the inspectors were more inclined to emphasise the developmental dimension. The teachers were unanimous in their perception of the inspectors as persons of sensitivity. courtesy and credibility and appreciated the fact that they engaged actively with the children in the classroom. However, they declared that the inspections had made little or no useful impact, and the field inspectors expressed a similar opinion. Given the lack of consensus on what constitutes the role and function of inspectors, the research questions the validity of this judgement. It is argued that whole school inspection is best seen as an exercise located within the naturalist paradigm. and that its impact is percolative in nature and not readily amenable to positivist measurement. While acknowledging shortcomings especially in the area of reporting, the problematic nature of identifying the direction of causality is discussed in support of this position. Arising from this, suggestions for development are offered and these centre on a vision of whole school inspection as an operation that seeks to validate assisted self-review arrangements by the provision of high quality evaluation and strategic advice. The lesson for the Department of Education and Science is that school self-evaluation ought to be promoted on a systematic basis nationally. 'The implication for inspectors is that they should be released from the discharge of great many duties that distract them from their core work of providing information and analysis on the individual school and on the system in general. It is suggested that to the extent this happens whole school inspection will be nearer the realisation of its potential