Yang-Mills origin of gravitational symmetries

By regarding gravity as the convolution of left and right Yang-Mills theories together with a spectator scalar field in the biadjoint representation, we derive in linearized approximation, the gravitational symmetries of general covariance, p-form gauge invariance, local Lorentz invariance, and local supersymmetry from the flat space Yang-Mills symmetries of local gauge invariance and global super-Poincaré symmetry. As a concrete example, we focus on the new minimal (12+12) off shell version of simple four-dimensional supergravity obtained by tensoring the off shell Yang-Mills multiplets (4+4, N_{L}=1) and (3+0, N_{R}=0).

Design and preliminary recruitment results of the Cluster randomised triAl of PSA testing for Prostate cancer (CAP)

BACKGROUND

Screening for prostate cancer continues to generate controversy because of concerns about over-diagnosis and unnecessary treatment. We describe the rationale, design and recruitment of the Cluster randomised triAl of PSA testing for Prostate cancer (CAP) trial, a UK-wide cluster randomised controlled trial investigating the effectiveness and cost-effectiveness of prostate-specific antigen (PSA) testing.

METHODS

Seven hundred and eighty-five general practitioner (GP) practices in England and Wales were randomised to a population-based PSA testing or standard care and then approached for consent to participate. In the intervention arm, men aged 50-69 years were invited to undergo PSA testing, and those diagnosed with localised prostate cancer were invited into a treatment trial. Control arm practices undertook standard UK management. All men were flagged with the Health and Social Care Information Centre for deaths and cancer registrations. The primary outcome is prostate cancer mortality at a median 10-year-follow-up.

RESULTS

Among randomised practices, 271 (68%) in the intervention arm (198,114 men) and 302 (78%) in the control arm (221,929 men) consented to participate, meeting pre-specified power requirements. There was little evidence of differences between trial arms in measured baseline characteristics of the consenting GP practices (or men within those practices).

CONCLUSIONS

The CAP trial successfully met its recruitment targets and will make an important contribution to international understanding of PSA-based prostate cancer screening.

Magic square from Yang-Mills squared

We give a unified description of D=3 super-Yang-Mills theory with N=1, 2, 4, and 8 supersymmeties in terms of the four division algebras: reals (R), complexes (C), quaternions (H) and octonions (O). Tensoring left and right super-Yang-Mills multiplets with N=1, 2, 4, 8 we obtain a magic square RR, CR, CC, HR, HC, HH, OR, OC, OH, OO description of D=3 supergravity with N=2, 3, 4, 5, 6, 8, 9, 10, 12, 16.

Multistage wastewater treatment using separated storage driven denitrification and nitrification biofilms

The feasibility of combining a previously reported storage driven denitrification biofilm, where 80% of influent acetate can be converted to poly-beta-hydroxybutyrate (PHB), with a suitable nitrification reactor, either submerged or trickling filter design, to achieve complete biological nitrogen removal was tested. The reactor system showed the potential of complete biological nitrogen removal of waste streams with a C/N ratio as low as 3.93 kg COD/kg N-NH3 at an overall nitrogen removal rate of 1.1 mmole NH3/L/h. While the efficiency and the rates of nitrogen removal were higher than what is observed in traditional or simultaneous nitrification and denitrification (SND) systems, there were two problems that require further development: (a) the incomplete draining of the reactor caused ammonia retention and release in the effluent, limiting the overall N-removal and (b) pH drifts in the nitrification step slowed down the rate of nitrification if not corrected by appropriate pH adjustment or buffering.

Functionally associated molecular genetic marker map construction in perennial ryegrass (Lolium perenne L.)

A molecular marker-based map of perennial ryegrass (Lolium perenne L.) has been constructed through the use of polymorphisms associated with expressed sequence tags (ESTs). A pair-cross between genotypes from a North African ecotype and the cultivar Aurora was used to generate a two-way pseudo-testcross population. A selection of 157 cDNAs assigned to eight different functional categories associated with agronomically important biological processes was used to detect polymorphic EST-RFLP loci in the F(1)(NA(6) x AU(6)) population. A comprehensive set of EST-SSR markers was developed from the analysis of 14,767 unigenes, with 310 primer pairs showing efficient amplification and detecting 113 polymorphic loci. Two parental genetic maps were produced: the NA(6) genetic map contains 88 EST-RFLP and 71 EST-SSR loci with a total map length of 963 cM, while the AU(6) genetic map contains 67 EST-RFLP and 58 EST-SSR loci with a total map length of 757 cM. Bridging loci permitted the alignment of homologous chromosomes between the parental maps, and a sub-set of genomic DNA-derived SSRs was used to relate linkage groups to the perennial ryegrass reference map. Regions of segregation distortion were identified, in some instances in common with other perennial ryegrass maps. The EST-derived marker-based map provides the basis for in silico comparative genetic mapping, as well as the evaluation of co-location between QTLs and functionally associated genetic loci.

Functionally associated molecular genetic marker map construction in perennial ryegrass (Lolium perenne L.)

A molecular marker-based map of perennial ryegrass (Lolium perenne L.) has been constructed through the use of polymorphisms associated with expressed sequence tags (ESTs). A pair-cross between genotypes from a North African ecotype and the cultivar Aurora was used to generate a two-way pseudo-testcross population. A selection of 157 cDNAs assigned to eight different functional categories associated with agronomically important biological processes was used to detect polymorphic EST-RFLP loci in the F(1)(NA(6) x AU(6)) population. A comprehensive set of EST-SSR markers was developed from the analysis of 14,767 unigenes, with 310 primer pairs showing efficient amplification and detecting 113 polymorphic loci. Two parental genetic maps were produced: the NA(6) genetic map contains 88 EST-RFLP and 71 EST-SSR loci with a total map length of 963 cM, while the AU(6) genetic map contains 67 EST-RFLP and 58 EST-SSR loci with a total map length of 757 cM. Bridging loci permitted the alignment of homologous chromosomes between the parental maps, and a sub-set of genomic DNA-derived SSRs was used to relate linkage groups to the perennial ryegrass reference map. Regions of segregation distortion were identified, in some instances in common with other perennial ryegrass maps. The EST-derived marker-based map provides the basis for in silico comparative genetic mapping, as well as the evaluation of co-location between QTLs and functionally associated genetic loci.

Underutilization of neuropsychology in traumatic brain injury rehabilitation: is managed care to blame?

We evaluated factors determining which individuals received neuropsychological evaluations (NPEs) following traumatic brain injury (TBI). Comprehensive records from a State-wide/sponsored Head Injury Program were followed from 1985--1995 to monitor effects of managed care on provision (or absence) of formal NPEs and ultimately on rehabilitation outcome. Only 26% of 273 individuals received NPEs (within their first three years post-injury). In the years prior to and after large changes in managed care, there were no differences in the provision of formal NPEs. Discriminant analysis identified functional status at discharge from primary rehabilitation and total number of rehabilitation facilities as the two variables that most distinguished those who had received NPEs with 69% classification accuracy. Between group analyses revealed that individuals were more likely to receive NPEs if they were young, involved in liability claims, attended multiple rehabilitation facilities, or had higher functional status at discharge from primary rehabilitation, regardless of the nature or severity of their TBI. Individuals receiving formal NPEs ultimately achieved higher levels of functional independence, suggesting a potential selection bias. Individuals were no more likely to receive NPEs according to insurance status (private versus government assisted) or as a function of the decade of their injury (1980's versus 1990's). It appears that health-care reform has had no deleterious effect on neuropsychologists' ability to provide consultative services for this population, and following TBI, only a discrete sample of individuals receive and benefit from NPEs.

Risk of hepatoblastoma in familial adenomatous polyposis

Infantile and childhood hepatoblastoma occurs more frequently in persons heterozygous for the familial adenomatous polyposis (FAP) gene than in the general population. This observation is based on numerous case reports plus the results of an international survey of FAP registries. However, the frequency of this rare tumor in FAP patients is unknown. In a retrospective review of our family history data, 2/470 (0.42%) children born to 241 patients with FAP had hepatoblastoma. This figure is significantly higher than the 1/100,000 incidence of hepatoblastoma in the general population. However, for genetic counseling purposes, an empiric risk of less than 1% for hepatoblastoma can be cited to persons with FAP for their children.