Public Private Partnerships: a Licence to Print Money or Value for Money?

It is often considered that a Public Private Partnership (PPP) is a licence to print money for the private entity and that the state receives a price which does reflect the value of the underlying public asset. This paper explores key concepts that underpin and define the nature of PPPs and how such partnerships have emerged and evolved as a means of project funding. The relationship between the underlying asset and the ownership of the derived benefit from the consumption of the public asset is explored to illustrate how the same asset can represent different values

Vector Pascal: a computer programming language for the FPS-164 array processor

Support for vector operations in computer programming languages is analyzed to determine if programs employing such operations run faster;The programming language Vector Pascal is defined and compared to Fortran 8X and Actus. Vector Pascal contains definitions for matrix and vector operations and the Vector Pascal compiler translates vector expressions. The Vector Pascal compiler executes on an IBM Personal Computer AT and produces code for a Floating Point Systems FPS-164 Scientific Computer;The standard benchmark LINPACK, which solves systems of linear equations, is transcribed from Fortran to Standard Pascal and Vector Pascal. The Vector Pascal version of LINPACK exploits vector operations defined in the language. The speedup of the Vector Pascal version of LINPACK over the Standard Pascal version is presented

Nonparametric estimation of correlation functions in longitudinal and spatial data, with application to colon carcinogenesis experiments

In longitudinal and spatial studies, observations often demonstrate strong correlations that are stationary in time or distance lags, and the times or locations of these data being sampled may not be homogeneous. We propose a nonparametric estimator of the correlation function in such data, using kernel methods. We develop a pointwise asymptotic normal distribution for the proposed estimator, when the number of subjects is fixed and the number of vectors or functions within each subject goes to infinity. Based on the asymptotic theory, we propose a weighted block bootstrapping method for making inferences about the correlation function, where the weights account for the inhomogeneity of the distribution of the times or locations. The method is applied to a data set from a colon carcinogenesis study, in which colonic crypts were sampled from a piece of colon segment from each of the 12 rats in the experiment and the expression level of p27, an important cell cycle protein, was then measured for each cell within the sampled crypts. A simulation study is also provided to illustrate the numerical performance of the proposed method.Comment: Published in at http://dx.doi.org/10.1214/009053607000000082 the Annals of Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical Statistics (http://www.imstat.org

Diversity and evolution of the small multidrug resistance protein family

<p>Abstract</p> <p>Background</p> <p>Members of the small multidrug resistance (SMR) protein family are integral membrane proteins characterized by four α-helical transmembrane strands that confer resistance to a broad range of antiseptics and lipophilic quaternary ammonium compounds (QAC) in bacteria. Due to their short length and broad substrate profile, SMR proteins are suggested to be the progenitors for larger α-helical transporters such as the major facilitator superfamily (MFS) and drug/metabolite transporter (DMT) superfamily. To explore their evolutionary association with larger multidrug transporters, an extensive bioinformatics analysis of SMR sequences (> 300 Bacteria taxa) was performed to expand upon previous evolutionary studies of the SMR protein family and its origins.</p> <p>Results</p> <p>A thorough annotation of unidentified/putative SMR sequences was performed placing sequences into each of the three SMR protein subclass designations, namely small multidrug proteins (SMP), suppressor of <it>groEL </it>mutations (SUG), and paired small multidrug resistance (PSMR) using protein alignments and phylogenetic analysis. Examination of SMR subclass distribution within Bacteria and Archaea taxa identified specific Bacterial classes that uniquely encode for particular SMR subclass members. The extent of selective pressure acting upon each SMR subclass was determined by calculating the rate of synonymous to non-synonymous nucleotide substitutions using Syn-SCAN analysis. SUG and SMP subclasses are maintained under moderate selection pressure in comparison to integron and plasmid encoded SMR homologues. Conversely, PSMR sequences are maintained under lower levels of selection pressure, where one of the two PSMR pairs diverges in sequence more rapidly than the other. SMR genomic loci surveys identified potential SMR efflux substrates based on its gene association to putative operons that encode for genes regulating amino acid biogenesis and QAC-like metabolites. SMR subclass protein transmembrane domain alignments to Bacterial/Archaeal transporters (BAT), DMT, and MFS sequences supports SMR participation in multidrug transport evolution by identifying common TM domains.</p> <p>Conclusion</p> <p>Based on this study, PSMR sequences originated recently within both SUG and SMP clades through gene duplication events and it appears that SMR members may be evolving towards specific metabolite transport.</p