Technology and Regional Development in the American Context

Many large cities in the developed countries have recently experienced a slow-down of growth, and in some cases, absolute contraction of their population size. These trends pertain in particular to old industrial agglomerations which often fail to adapt to the changing demands and locational requirements of modern production facilities and to differentiate their employment structure. Interrelations between industrial restructuring and urban regional change were among topics studied in the former Human Settlements and Services Area at IIASA. They are also of current research interest to the Regional and Urban Development Group. The paper by J. Rees, H. Stafford, R. Briggs and R. Oakey touches on several aspects of those interdependencies, especially the question of how do high-technology complexes develop over space. Part II of the paper has been done within a framework of an international collaboration project involving similar studies in the U.K. and F.R.G. and coordinated by Professor John Goddard of Newcastle, U.K

Chromosome-wide identification of novel imprinted genes using microarrays and uniparental disomies

Genomic imprinting refers to a specialized form of epigenetic gene regulation whereby the expression of a given allele is dictated by parental origin. Defining the extent and distribution of imprinting across genomes will be crucial for understanding the roles played by imprinting in normal mammalian growth and development. Using mice carrying uniparental disomies or duplications, microarray screening and stringent bioinformatics, we have developed the first large-scale tissue-specific screen for imprinted gene detection. We quantify the stringency of our methodology and relate it to previous non-tissue-specific large-scale studies. We report the identification in mouse of four brain-specific novel paternally expressed transcripts and an additional three genes that show maternal expression in the placenta. The regions of conserved linkage in the human genome are associated with the Prader–Willi Syndrome (PWS) and Beckwith–Wiedemann Syndrome (BWS) where imprinting is known to be a contributing factor. We conclude that large-scale systematic analyses of this genre are necessary for the full impact of genomic imprinting on mammalian gene expression and phenotype to be elucidated

Estimation in a multiplicative mixed model involving a genetic relationship matrix

Genetic models partitioning additive and non-additive genetic effects for populations tested in replicated multi-environment trials (METs) in a plant breeding program have recently been presented in the literature. For these data, the variance model involves the direct product of a large numerator relationship matrix A, and a complex structure for the genotype by environment interaction effects, generally of a factor analytic (FA) form. With MET data, we expect a high correlation in genotype rankings between environments, leading to non-positive definite covariance matrices. Estimation methods for reduced rank models have been derived for the FA formulation with independent genotypes, and we employ these estimation methods for the more complex case involving the numerator relationship matrix. We examine the performance of differing genetic models for MET data with an embedded pedigree structure, and consider the magnitude of the non-additive variance. The capacity of existing software packages to fit these complex models is largely due to the use of the sparse matrix methodology and the average information algorithm. Here, we present an extension to the standard formulation necessary for estimation with a factor analytic structure across multiple environments

Stirring by small-scale vortices caused by patchy mixing

Author Posting. © American Meteorological Society, 2005. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 35 (2005): 1245-1262, doi:10.1175/JPO2713.1.Evidence is presented that lateral dispersion on scales of 1–10 km in the stratified waters of the continental shelf may be significantly enhanced by stirring by small-scale geostrophic motions caused by patches of mixed fluid adjusting in the aftermath of diapycnal mixing events. Dye-release experiments conducted during the recent Coastal Mixing and Optics (CMO) experiment provide estimates of diapycnal and lateral dispersion. Microstructure observations made during these experiments showed patchy turbulence on vertical scales of 1–10 m and horizontal scales of a few hundred meters to a few kilometers. Momentum scaling and a simple random walk formulation were used to estimate the effective lateral dispersion caused by motions resulting from lateral adjustment following episodic mixing events. It is predicted that lateral dispersion is largest when the scale of mixed patches is on the order of the internal Rossby radius of deformation, which seems to have been the case for CMO. For parameter values relevant to CMO, lower-bound estimates of the effective lateral diffusivity by this mechanism ranged from 0.1 to 1 m2s−1. Revised estimates after accounting for the possibility of long-lived motions were an order of magnitude larger and ranged from 1 to 10 m2s−1. The predicted dispersion is large enough to explain the observed lateral dispersion in all four CMO dye-release experiments examined.The Coastal Mixing and Optics dye studies were funded by the Office of Naval Research under Grants N00014-95-1-0633 (tracer experiments) and N00014-95-1-1063 (AASERT fellowship). Additional analysis was also performed under ONR Grant N00014-01-1-0984

A cohort study of duplicate faecal immunochemical testing in patients at risk of colorectal cancer from North-West England

Objectives We sought to investigate if duplicate faecal immunochemical testing (FIT) sampling improves the negative and positive predictive value of patients thought to be at risk of colorectal cancer (CRC). Specifically, we aimed to investigate whether the proportion of FIT-negative CRC missed by a single FIT test in symptomatic patients could be reduced by duplicate FIT testing. Design A retrospective service evaluation cohort study of the diagnostic accuracy of duplicate FIT testing. Setting Patients referred from primary care with suspected CRC to four secondary care trusts in North-West England. Participants 28 622 patients over 18-years-old with lower gastrointestinal symptoms suggestive of CRC who completed two FIT samples. Primary and secondary outcome measures The performance of duplicate FIT for detecting CRC at a threshold of 10 µgHb/g. Results The sensitivity if either test was >10 µgHb/g was 0.978 (0.955–0.989), specificity was 0.662 (0.657–0.668), positive predictive value 0.031 (0.028–0.035) and negative predictive value 1.00 (0.999–1.00). Despite two-thirds of patients (18952) being negative following two tests, at this threshold only seven CRC were missed over a 26-month period. All seven patients had other high-risk features which should have prompted investigation. Conclusions This study suggests that in routine NHS practice, a duplicate FIT sample strategy together with clinical evaluation for evidence of anaemia and weight loss is superior to a single FIT sample alone and would allow sy

Diapycnal mixing in the Antarctic Circumpolar Current

Author Posting. © American Meteorological Society, 2011. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 41 (2011): 241-246, doi:10.1175/2010JPO4557.1.The vertical dispersion of a tracer released on a density surface near 1500-m depth in the Antarctic Circumpolar Current west of Drake Passage indicates that the diapycnal diffusivity, averaged over 1 yr and over tens of thousands of square kilometers, is (1.3 ± 0.2) × 10−5 m2 s−1. Diapycnal diffusivity estimated from turbulent kinetic energy dissipation measurements about the area occupied by the tracer in austral summer 2010 was somewhat less, but still within a factor of 2, at (0.75 ± 0.07) × 10−5 m2 s−1. Turbulent diapycnal mixing of this intensity is characteristic of the midlatitude ocean interior, where the energy for mixing is believed to derive from internal wave breaking. Indeed, despite the frequent and intense atmospheric forcing experienced by the Southern Ocean, the amplitude of finescale velocity shear sampled about the tracer was similar to background amplitudes in the midlatitude ocean, with levels elevated to only 20%–50% above the Garrett–Munk reference spectrum. These results add to a long line of evidence that diapycnal mixing in the interior middepth ocean is weak and is likely too small to dictate the middepth meridional overturning circulation of the ocean.This material is based upon work supported by the National Science Foundation Grants OCE-0622825,OCE-0622670, OCE-0622630, and OCE-0623177

Candidate knowledge? Exploring epistemic claims in scientific writing:a corpus-driven approach

In this article I argue that the study of the linguistic aspects of epistemology has become unhelpfully focused on the corpus-based study of hedging and that a corpus-driven approach can help to improve upon this. Through focusing on a corpus of texts from one discourse community (that of genetics) and identifying frequent tri-lexical clusters containing highly frequent lexical items identified as keywords, I undertake an inductive analysis identifying patterns of epistemic significance. Several of these patterns are shown to be hedging devices and the whole corpus frequencies of the most salient of these, candidate and putative, are then compared to the whole corpus frequencies for comparable wordforms and clusters of epistemic significance. Finally I interviewed a ‘friendly geneticist’ in order to check my interpretation of some of the terms used and to get an expert interpretation of the overall findings. In summary I argue that the highly unexpected patterns of hedging found in genetics demonstrate the value of adopting a corpus-driven approach and constitute an advance in our current understanding of how to approach the relationship between language and epistemology