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Data Alone (data + alone)
Selected AbstractsCasenote assessment of psychopathy in a high security hospitalCRIMINAL BEHAVIOUR AND MENTAL HEALTH, Issue 1 2001Dr David Reiss Introduction There is now a large amount of data demonstrating the internal reliability and construct validity of the Hare Psychopathy Checklist (PCL/PCL-R) when used in the assessment of psychopathy in male forensic populations. It has well-established psychometric properties when scored following a review of collateral information and a subsequent interview. However, its internal reliability and factor structure, when casenote information alone has been used, have not been examined outside North America. Method A sample of 89 patients from a British high security hospital, with the legal classification of psychopathic disorder, was scored retrospectively on the PCL-R from their medical files only. The psychometric properties of the PCL-R were analysed. Results The PCL-R ratings showed a high level of internal reliability. The factor structure was very similar to that found in Hare's North American sample of forensic psychiatric patients. Discussion The findings support the application of the PCL-R, when scored using existing file data alone, to a British high security hospital population. Copyright © 2001 Whurr Publishers Ltd. [source] Eukaryotic diversity and phylogeny using small- and large-subunit ribosomal RNA genes from environmental samplesENVIRONMENTAL MICROBIOLOGY, Issue 12 2009William Marande Summary The recent introduction of molecular techniques in eukaryotic microbial diversity studies, in particular those based in the amplification and sequencing of small-subunit ribosomal DNA (SSU rDNA), has revealed the existence of an unexpected variety of new phylotypes. The taxonomic ascription of the organisms bearing those sequences is generally deduced from phylogenetic analysis. Unfortunately, the SSU rDNA sequence alone has often not enough phylogenetic information to resolve the phylogeny of fast-evolving or very divergent sequences, leading to their misclassification. To address this problem, we tried to increase the phylogenetic signal by amplifying the complete eukaryotic rDNA cluster [i.e. the SSU rDNA, the internal transcribed spacers, the 5.8S rDNA and the large-subunit (LSU) rDNA] from environmental samples, and sequencing the SSU and LSU rDNA part of the clones. Using marine planktonic samples, we showed that surveys based on either SSU or SSU + LSU rDNA retrieved comparable diversity patterns. In addition, phylogenetic trees based on the concatenated SSU + LSU rDNA sequences showed better resolution, yielding good support for major eukaryotic groups such as the Opisthokonta, Rhizaria and Excavata. Finally, highly divergent SSU rDNA sequences, whose phylogenetic position was impossible to determine with the SSU rDNA data alone, could be placed correctly with the SSU + LSU rDNA approach. These results suggest that this method can be useful, in particular for the analysis of eukaryotic microbial communities rich in phylotypes of difficult phylogenetic ascription. [source] Extensional development of the Fundy rift basin, southeastern CanadaGEOLOGICAL JOURNAL, Issue 6 2009Martha O. Withjack Abstract The Fundy rift basin of Nova Scotia and New Brunswick, Canada, is part of the Eastern North American rift system that formed during the breakup of Pangaea. Integrated seismic-reflection, field, digital-elevation and aeromagnetic data indicate that the Fundy rift basin underwent two phases of deformation: syn-rift extension followed by post-rift basin inversion. Inversion significantly modified the geometries of the basin and its rift-related structures. In this paper, we remove the effects of inversion to examine the basin's extensional development. The basin consists of three structural subbasins: the Fundy and Chignecto subbasins are bounded by low-angle, NE-striking faults; the Minas subbasin is bounded by E- to ENE-striking faults that are steeply dipping at the surface and gently dipping at depth. Together, these linked faults form the border,fault system of the Fundy rift basin. Most major faults within the border,fault system originated as Palaeozoic contractional structures. All syn-rift units imaged on seismic profiles thicken towards the border,fault system, reflecting extensional movement from Middle Triassic (and possibly Permian) through Early Jurassic time. Intra-rift unconformities, observed on seismic profiles and in the field, indicate that uplift and erosion occurred, at least locally, during rifting. Based on seismic data alone, the displacement direction of the hanging wall of the border,fault system of the Fundy rift basin ranged from SW to SE during rifting. Field data (i.e. NE-striking igneous dykes, sediment-filled fissures and normal faults) indicate NW,SE extension during Early Jurassic time, supporting a SE-displacement direction. With a SE-displacement direction, the NE-striking border,fault zones of the Fundy and Chignecto subbasins had predominantly normal dip slip during rifting, whereas the E-striking border,fault zone of the Minas subbasin had oblique slip with left-lateral and normal components. Sequential restorations of seismic-reflection profiles (coupled with projections from onshore geology) show that the Fundy rift basin underwent 10,20,km of extension, most of which was accommodated by the border,fault system, and was considerably wider and deeper prior to basin inversion. Post-rift deformation tilted the eastern side of the basin to the northwest/north, producing significant uplift and erosion. Copyright © 2009 John Wiley & Sons, Ltd. [source] Risk Segmentation Related to the Offering of a Consumer-Directed Health Plan: A Case Study of Humana Inc.HEALTH SERVICES RESEARCH, Issue 4p2 2004Laura A. Tollen Objective. To determine whether the offering of a consumer-directed health plan (CDHP) is likely to cause risk segmentation in an employer group. Study Setting and Data Source. The study population comprises the approximately 10,000 people (employees and dependents) enrolled as members of the employee health benefit program of Humana Inc. at its headquarters in Louisville, Kentucky, during the benefit years starting July 1, 2000, and July 1, 2001. This analysis is based on primary collection of claims, enrollment, and employment data for those employees and dependents. Study Design. This is a case study of the experience of a single employer in offering two consumer-directed health plan options ("Coverage First 1" and "Coverage First 2") to its employees. We assessed the risk profile of those choosing the Coverage First plans and those remaining in more traditional health maintenance organization (HMO) and preferred provider organization (PPO) coverage. Risk was measured using prior claims (in dollars per member per month), prior utilization (admissions/1,000; average length of stay; prescriptions/1,000; physician office visit services/1,000), a pharmacy-based risk assessment tool (developed by Ingenix), and demographics. Data Collection/Extraction Methods. Complete claims and administrative data were provided by Humana Inc. for the two-year study period. Unique identifiers enabled us to track subscribers' individual enrollment and utilization over this period. Principal Findings. Based on demographic data alone, there did not appear to be a difference in the risk profiles of those choosing versus not choosing Coverage First. However, based on prior claims and prior use data, it appeared that those who chose Coverage First were healthier than those electing to remain in more traditional coverage. For each of five services, prior-year usage by people who subsequently enrolled in Coverage First 1 (CF1) was below 60 percent of the average for the whole group. Hospital and maternity admissions per thousand were less than 30 percent of the overall average; length of stay per hospital admission, physician office services per thousand, and prescriptions per thousand were all between 50 and 60 percent of the overall average. Coverage First 2 (CF2) subscribers' prior use of services was somewhat higher than CF1 subscribers', but it was still below average in every category. As with prior use, prior claims data indicated that Coverage First subscribers were healthier than average, with prior total claims less than 50 percent of average. Conclusions. In this case, the offering of high-deductible or consumer-directed health plan options alongside more traditional options caused risk segmentation within an employer group. The extent to which these findings are applicable to other cases will depend on many factors, including the employer premium contribution policies and employees' perception of the value of the various plan options. Further research is needed to determine whether risk segmentation will worsen in future years for this employer and if so, whether it will cause premiums for more traditional health plans to increase. [source] Measuring the Quality of Diabetes Care Using Administrative Data: Is There Bias?HEALTH SERVICES RESEARCH, Issue 6p1 2003Nancy L. Keating Objectives. Health care organizations often measure processes of care using only administrative data. We assessed whether measuring processes of diabetes care using administrative data without medical record data is likely to underdetect compliance with accepted standards for certain groups of patients. Data Sources/Study Setting. Assessment of quality indicators during 1998 using administrative and medical records data for a cohort of 1,335 diabetic patients enrolled in three Minnesota health plans. Study Design. Cross-sectional retrospective study assessing hemoglobin A1c testing, LDL cholesterol testing, and retinopathy screening from the two data sources. Analyses examined whether patient or clinic characteristics were associated with underdetection of quality indicators when administrative data were not supplemented with medical record data. Data Collection/Extraction Methods. The health plans provided administrative data, and trained abstractors collected medical records data. Principal Findings. Quality indicators that would be identified if administrative data were supplemented with medical records data are often not identified using administrative data alone. In adjusted analyses, older patients were more likely to have hemoglobin A1c testing underdetected in administrative data (compared to patients <45 years, OR 2.95, 95 percent CI 1.09 to 7.96 for patients 65 to 74 years, and OR 4.20, 95 percent CI 1.81 to 9.77 for patients 75 years and older). Black patients were more likely than white patients to have retinopathy screening underdetected using administrative data (2.57, 95 percent CI 1.16 to 5.70). Patients in different health plans also differed in the likelihood of having quality indicators underdetected. Conclusions. Diabetes quality indicators may be underdetected more frequently for elderly and black patients and the physicians, clinics, and plans who care for such patients when quality measurement is based on administrative data alone. This suggests that providers who care for such patients may be disproportionately affected by public release of such data or by its use in determining the magnitude of financial incentives. [source] Radar-guided interpolation of climatological precipitation dataINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 2 2009Arthur T. DeGaetano Abstract A refined approach for interpolating daily precipitation accumulations is presented, which combines radar-based information to characterize the spatial distribution and gross accumulation of precipitation with observed daily rain-gauge data to adjust for spatially varying errors in the radar estimates. Considering the rain gauge observations to be true values at each measurement location, daily radar errors are calculated at these points. These errors are then interpolated back to the radar grid, providing a spatially varying daily adjustment that can be applied across the radar domain. In contrast to similar techniques that are employed at hourly intervals to adjust radar-rainfall estimates operationally, this refined approach is intended to provide high-spatial-resolution precipitation data for climatological purposes, such as drought and environmental monitoring, retrospective impact analyses, and (when time series of sufficient length become available) assessment of temporal precipitation variations at high-spatial-resolution. Compared to the Multisensor Precipitation Estimators (MPEs) used operationally, the refined method yields lower cross-validated interpolation errors regardless of season or daily precipitation amount. Comparisons between cross-validated radar estimates aggregated to monthly totals with operational (non-cross-validated) Parameter-elevation Regressions on Independent Slopes Model (PRISM) precipitation estimates are also favourable. The new method provides a radar-based alternative to similar climatologies based on the spatial interpolation of gauge data alone (e.g. PRISM). Copyright © 2008 Royal Meteorological Society [source] Spatial grouping of United States climate stations using a hybrid clustering approachINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 7 2001Arthur T. DeGaetano Abstract The development of a hybrid clustering technique based on the geographic proximity of observing stations and some application-driven measure of statistical similarity (in this case rank correlation) is described. The procedure is then applied to temperature and precipitation data from the United States (US) Historical Climatology Network. The resulting station groups provide some insight into the number of observation stations that are necessary to monitor adequately the climate of the US. Based on temperature data alone, a 287-station subset of the original 1145 sites would be adequate to account for 80% of the spatial variability in seasonal temperature across the US. Geographically the distribution of these stations would be relatively sparse in the centre of the country with higher station density along the East Coast and from the Rocky Mountains to the West Coast. Generally, the temperature clusters match the existing US climate divisions to some extent. To monitor adequately the spatial variability of precipitation, a network of similar size could be used. However, such a network would only account for 65% of the spatial variability in precipitation. In this case, fairly uniform station density is indicated across the country with the highest station density in Florida and the Dakotas. A similar number of stations, but with slightly different geographic groupings would be adequate to monitor precipitation and temperature simultaneously. Copyright © 2001 Royal Meteorological Society [source] From Illegal to Legal: Estimating Previous Illegal Experience among New Legal Immigrants to the United States1INTERNATIONAL MIGRATION REVIEW, Issue 4 2008Guillermina Jasso This paper develops a framework for estimating previous illegal experience among annual cohorts of new legal immigrants to the United States , using public-use administrative microdata alone, survey data alone, and the two jointly , and provides estimates for the FY 1996 cohort of new immigrants, based on both administrative and survey data. Our procedures enable assessment of type of illegal experience, including entry without inspection, visa overstay, and unauthorized employment. We compare our estimates of previous illegal experience to estimates that would be obtained using administrative data alone; examine the extent of previous illegal experience by country of birth, immigrant class of admission, religion, and geographic residence in the United States; and estimate multivariate models of the probability of having previous illegal experience. To further assess origins and destinations, we carry out two kinds of contrasts, comparing formerly illegal new legal immigrants both to fellow immigrants who do not have previous illegal experience and also to the broader unauthorized population, the latter using estimates developed by the U.S. Department of Homeland Security (2002), Passel (2002), and Costanzo et al. (2002). [source] Reproductive skew in birds: models, problems and prospectsJOURNAL OF AVIAN BIOLOGY, Issue 2 2000Robert D. Magrath In recent years there has been a resurgence of interest in models to explain the partitioning of direct reproduction (,reproductive skew') among members of one sex within social groups. We review models of skew, identify problems of testing models, and consider how to make progress. One series of models assumes that dominants have complete control of subordinate reproduction, but may allow subordinates some reproduction as a way of enticing them to help or getting them to share the cost of reproduction. Another series of models assume that dominants have limited control of subordinate reproduction. Reproductive skew may also be affected by incest avoidance or control by the opposite sex. Models are largely untested because no study of birds has quantified all relevant parameters, and we see no prospect of this happening soon. A common simplifying approach is to test qualitative predictions about the effect on skew of relatedness among group members. However, these data alone cannot distinguish among models because models do not make unique predictions, partly because skew is also affected by other factors. A major problem in cooperatively-breeding birds is that any effect of relatedness will often be confounded by covariation with relatedness asymmetry and subordinate competitiveness. Progress can be made with the development of theory, controlling confounding variables through the choice of study species or types of social group, and, most importantly, testing assumptions underlying hypotheses. [source] Age Estimation Using Thoracic and First Two Lumbar Vertebral Ring Epiphyseal UnionJOURNAL OF FORENSIC SCIENCES, Issue 2 2010Midori Albert Ph.D. Abstract:, Union of the vertebral centra or "ring" epiphyses occurs during adolescence and early adulthood, providing valuable age at death information. We present a system for estimating age based on the timing and pattern of vertebral ring union. Data from 57 known individuals aged 14,27 years were used to establish age ranges for various patterns of union in females and males. Female age ranges were more well defined with less overlap in patterns of union than male age ranges. The age ranges are accompanied by descriptions of the stages of union observed that aid in applying this method. A test of interobserver error in scoring stages of union demonstrated strong consistency among three observers (r = 0.91,0.97). Estimating age by observing all stages documented resulted in 78%, 88%, and 100% accuracies using vertebral data alone. We encourage the continued use of this method, in conjunction with other age indicators. [source] IDENTIFICATION OF SALT FEATURES IN SEISMIC DATAJOURNAL OF PETROLEUM GEOLOGY, Issue 4 2008M. K. Jenyon Deciding on the viability of a salt deposit as a possible site for storage-cavern solution mining requires detailed geological studies of the salt and of its confining formations. Borehole data alone can seldom deliver the information required for such a study. It can impart great detail of the subsurface but only at the actual borehole location in an area. The most practical approach to developing 3D information is to carry out a seismic survey tied in to one or more boreholes which have been logged geophysically Ideally, a high-resolution seismic survey is needed to study relatively shallow zones of the subsurface and resolve the top and base of fairly thin beds. However in some cases it is possible to use "reach-me-down" seismic data acquired previously during hydrocarbon exploration. Although these data were not designed to meet the requirements of salt deposit studies, they may still be adequate for the purpose. Their use will lead to quicker and lower-cost results than the commissioning of a full field seismic survey with concomitant processing, although in both cases a seismic interpretation would be required. [source] 15 Phylogeny of the chlorophyta: inferences from 18S and 26S rDNAJOURNAL OF PHYCOLOGY, Issue 2003M. A. Buchheim Recent studies of the Chlorophyceae using 18S and 26S rDNA data in meta-analysis have demonstrated the power of combining these two sets of rDNA data. Furthermore, the 26S rDNA data complement the more conserved 18S gene for many chlorophycean lineages. Consequently, this data approach was pursued in an expanded taxon-sampling scheme for the Chlorophyta, with special reference to the classes Chlorophyceae and Trebouxiophyceae. Results of these new phylogenetic analyses identify Microspora sp. (UTEX LB 472) and Radiofilum transversale (UTEX LB 1252) as sister taxa which, in turn, form a basal clade in the Cylindrocapsa alliance (Treubaria, Trochiscia, Elakatothrix). The relative position of the "Cylindrocapsa" clade within the Chlorophyceae remains uncertain. The enhanced taxon-sampling has not resolved the relative positions of the Oedogoniales, Chaetophorales or Chaetopeltidales. Furthermore, the Sphaeropleaceae are supported as members of the Sphaeropleales in only some analyses, raising concerns about the status of the order. Although based on a limited set of taxa (currently <10), a combined data approach reveals support for a monophyletic Trebouxiophyceae that includes the distinctive organisms, Geminella and Eremosphaera. The goal of a well-resolved phylogeny for the Chlorophyta remains just that, a goal. Achieving that goal obviously will require additional taxon sampling in the Prasinophyceae and Ulvophyceae, as well as, the Trebouxiophyceae. Moreover, it is clear that other genes (e.g., cp-atpB, cp-rbcL, cp-16S, mt-nad5) will be needed to help address problems of resolution based on the rDNA data alone. Supported by NSF DEB 9726588 and DEB 0129030. [source] On the Nitroxide Quasi-Equilibrium in the Alkoxyamine-Mediated Radical Polymerization of StyreneMACROMOLECULAR THEORY AND SIMULATIONS, Issue 2 2006Enrique Saldívar-Guerra Abstract Summary: The range of validity of two popular versions of the nitroxide quasi-equilibrium (NQE) approximation used in the theory of kinetics of alkoxyamine mediated styrene polymerization, are systematically tested by simulation comparing the approximate and exact solutions of the equations describing the system. The validity of the different versions of the NQE approximation is analyzed in terms of the relative magnitude of (dN/dt)/(dP/dt). The approximation with a rigorous NQE, kc[P][N],=,kd[PN], where P, N and PN are living, nitroxide radicals and dormant species respectively, with kinetic constants kc and kd, is found valid only for small values of the equilibrium constant K (10,11,10,12 mol,·,L,1) and its validity is found to depend strongly of the value of K. On the other hand, the relaxed NQE approximation of Fischer and Fukuda, kc[P][N],=,kd[PN]0 was found to be remarkably good up to values of K around 10,8 mol,·,L,1. This upper bound is numerically found to be 2,3 orders of magnitude smaller than the theoretical one given by Fischer. The relaxed NQE is a better one due to the fact that it never completely neglects dN/dt. It is found that the difference between these approximations lies essentially in the number of significant figures taken for the approximation; still this subtle difference results in dramatic changes in the predicted course of the reaction. Some results confirm previous findings, but a deeper understanding of the physico-chemical phenomena and their mathematical representation and another viewpoint of the theory is offered. Additionally, experiments and simulations indicate that polymerization rate data alone are not reliable to estimate the value of K, as recently suggested. Validity of the rigorous nitroxide quasi-equilibrium assumption as a function of the nitroxide equilibrium constant. [source] Evidence from ESR studies for [Co(,-C2H4)3] produced at 77 K in a rotating cryostat,MAGNETIC RESONANCE IN CHEMISTRY, Issue 10 2006Lynda J. Hayton Abstract Co atoms were reacted with ethene at 77 K and the paramagnetic products studied by electron spin resonance (ESR) at X- and K-bands. The ESR spectra of the major product at both frequencies showed eight cobalt multiplets (ICo = 7/2) indicating a mono-cobalt complex. The spectra have orthorhombic g and cobalt hyperfine tensors and were simulated by the parameters; g1 = 2.284, g2 = 2.0027, g3 = 2.1527; A1 < , 25 MHz, A2 = , 109 MHz, A3 = , 198 MHz. Proton and 13C (1% natural abundance) hyperfine couplings were lower than the line widths (<2 MHz) indicating less than 0.5 spin transfer to the ethene ligands. We assigned the spectrum to a Jahn,Teller-distorted planar trigonal mono-cobalt tris-ethene [Co(,-C2H4)3] complex in C2v symmetry. The SOMO is either a 3dx2,y2 (2a1) orbital in a T-geometry or a 3dxy (b1) orbital in a Y-geometry but there is only a spin density, a2, of 0.30 in these d orbitals. The spin deficiency of 0.70 is attributed to two factors; spin transfer from the Co to ethene ,/,* orbitals and a 4p orbital contribution, b2, to the SOMO. Calculations of a2 and b2 have been made at three levels of spin transfer, ,. At , = 0.00a2 is 0.23 and b2 is 0.78, at , = 0.25a2 is 0.25 and b2 is 0.52 and at , = 0.50a2 is 0.28 and b2 is 0.23. The other possible assignment to a mono-cobalt bis-ethene complex [Co(,-C2H4)2] cannot be discounted from the ESR data alone but is considered unlikely on other grounds. The complex is stable up to ,220 K indicating a barrier to decomposition of ,50 kJ Mol,1 Copyright © 2006 John Wiley & Sons, Ltd. [source] Iron oxidation state in impact glass from the K/T boundary at Beloc, Haiti, by high-resolution XANES spectroscopyMETEORITICS & PLANETARY SCIENCE, Issue 11 2005Gabriele Giuli The samples have been analyzed by Fe K-edge high-resolution X-ray absorption near edge structure (XANES) spectroscopy to obtain data on both the Fe oxidation state and the coordination number. The pre-edge peak of our high-resolution XANES spectra display noticeable variations indicative of significant changes in the Fe oxidation state spanning a wide range from about 20 to 75 mol% trivalent Fe. All data plot along the same trend, falling between two mixing lines joining a point calculated as the mean of a group of tektites studied so far (consisting of four- and five-coordinated Fe2+) to [4]Fe3+ and [5]Fe3+, respectively. Thus, the XANES spectra can be interpreted as a mixture of [4]Fe2+, [5]Fe2+, [4]Fe3+, and [5]Fe3+. There is no evidence for six-fold coordinated Fe; however, its presence in small amounts cannot be excluded from XANES data alone. Our observations can be explained by two possible scenarios: either these impact glasses formed under very reducing conditions and, because of their small size, were easily oxidized in air while still molten, or they formed under a variety of different oxygen fugacities resulting in different Fe oxidation states. In the first case, the oxidation state and coordination number would imply similar formation conditions as splash-form tektites, followed by progressive oxidation. [source] Stony meteorite porosities and densities: A review of the data through 2001METEORITICS & PLANETARY SCIENCE, Issue 8 2003D. T. Britt These data were taken from 925 samples of 454 different meteorites by a variety of techniques. Most meteorites have densities on the order of 3 to 4 g/cm3, with lower densities only for some volatile-rich carbonaceous meteorites and higher densities for stony irons. For the vast majority of stones, porosity data alone cannot distinguish between different meteorite compositions. Average porosities for most meteorite classes are around 10%, though individual samples can range as high as 30% porosity. Unbrecciated basaltic achondrites appear to be systematically less porous unless vesicles are present. The measured density of ordinary chondrites is strongly controlled by the amount of terrestrial weathering the sample has undergone with porosities steadily dropping with exposure to the terrestrial environment. A theoretical grain density based on composition can model "pre-weathered" porosities. The average model porosity for H and LL chondrites is 10%, while L chondrite model porosities average only 6%, a statistically significant difference. [source] Neither genetic nor observational data alone are sufficient for understanding sex-biased dispersal in a social-group-living speciesMOLECULAR ECOLOGY, Issue 8 2009T. R. HARRIS Abstract Complex sex-biased dispersal patterns often characterize social-group-living species and may ultimately drive patterns of cooperation and competition within and among groups. This study investigates whether observational data or genetic data alone can elucidate the potentially complex dispersal patterns of social-group-living black and white colobus monkeys (Colobus guereza, ,guerezas'), or whether combining both data types provides novel insights. We employed long-term observation of eight neighbouring guereza groups in Kibale National Park, Uganda, as well as microsatellite genotyping of these and two other neighbouring groups. We created a statistical model to examine the observational data and used dyadic relatedness values within and among groups to analyse the genetic data. Analyses of observational and genetic data both supported the conclusion that males typically disperse from their natal groups and often transfer into nearby groups and probably beyond. Both data types also supported the conclusion that females are more philopatric than males but provided somewhat conflicting evidence about the extent of female philopatry. Observational data suggested that female dispersal is rare or nonexistent and transfers into neighbouring groups do not occur, but genetic data revealed numerous pairs of closely related adult females among neighbouring groups. Only by combining both data types were we able to understand the complexity of sex-biased dispersal patterns in guerezas and the processes that could explain our seemingly conflicting results. We suggest that the data are compatible with a scenario of group dissolution prior to the start of this study, followed by female transfers into different neighbouring groups. [source] Using phylochronology to reveal cryptic population histories: review and synthesis of 29 ancient DNA studiesMOLECULAR ECOLOGY, Issue 7 2009UMA RAMAKRISHNAN Abstract The evolutionary history of a population involves changes in size, movements and selection pressures through time. Reconstruction of population history based on modern genetic data tends to be averaged over time or to be biased by generally reflecting only recent or extreme events, leaving many population historic processes undetected. Temporal genetic data present opportunities to reveal more complex population histories and provide important insights into what processes have influenced modern genetic diversity. Here we provide a synopsis of methods available for the analysis of ancient genetic data. We review 29 ancient DNA studies, summarizing the analytical methods and general conclusions for each study. Using the serial coalescent and a model-testing approach, we then re-analyse data from two species represented by these data sets in a common interpretive framework. Our analyses show that phylochronologic data can reveal more about population history than modern data alone, thus revealing ,cryptic' population processes, and enable us to determine whether simple or complex models best explain the data. Our re-analyses point to the need for novel methods that consider gene flow, multiple populations and population size in reconstruction of population history. We conclude that population genetic samples over large temporal and geographical scales, when analysed using more complex models and the serial coalescent, are critical to understand past population dynamics and provide important tools for reconstructing the evolutionary process. [source] Prospects for inferring pairwise relationships with single nucleotide polymorphismsMOLECULAR ECOLOGY, Issue 4 2003Jeffrey C. Glaubitz Abstract An extraordinarily large number of single nucleotide polymorphisms (SNPs) are now available in humans as well as in other model organisms. Technological advancements may soon make it feasible to assay hundreds of SNPs in virtually any organism of interest. One potential application of SNPs is the determination of pairwise genetic relationships in populations without known pedigrees. Although microsatellites are currently the marker of choice for this purpose, the number of independently segregating microsatellite markers that can be feasibly assayed is limited. Thus, it can be difficult to distinguish reliably some classes of relationship (e.g. full-sibs from half-sibs) with microsatellite data alone. We assess, via Monte Carlo computer simulation, the potential for using a large panel of independently segregating SNPs to infer genetic relationships, following the analytical approach of Blouin et al. (1996). We have explored a ,best case scenario' in which 100 independently segregating SNPs are available. For discrimination among single-generation relationships or for the identification of parent,offspring pairs, it appears that such a panel of moderately polymorphic SNPs (minor allele frequency of 0.20) will provide discrimination power equivalent to only 16,20 independently segregating microsatellites. Although newly available analytical methods that can account for tight genetic linkage between markers will, in theory, allow improved estimation of relationships using thousands of SNPs in highly dense genomic scans, in practice such studies will only be feasible in a handful of model organisms. Given the comparable amount of effort required for the development of both types of markers, it seems that microsatellites will remain the marker of choice for relationship estimation in nonmodel organisms, at least for the foreseeable future. [source] Across the Southern Alps by river capture?MOLECULAR ECOLOGY, Issue 10 2000Freshwater fish phylogeography in South Island, New Zealand Abstract We used DNA analysis of galaxiid fish to test a hypothesis of localized headwater capture in South Island, New Zealand. The restricted western, but widespread eastern, distributions of three nonmigratory freshwater fish species suggest that part of the east-flowing Waiau River has been captured by the west-flowing Buller River. However, mitochondrial control region (Kimura 2-parameter distance = 4.1,5.4%) and microsatellite flanking sequences do not support a relationship between Waiau (N = 4 fish sequences) and western populations (N = 8) of Galaxias vulgaris. Instead, the point of capture is probably to the north-east, perhaps the Nelson lakes region. Phylogenetic analysis indicates that western populations, along with populations in the north-east (N = 18), represent a previously unidentified monophyletic Evolutionarily Significant Unit, possibly a cryptic species. We suggest a general caveat for zoogeographic conclusions based on distributional data alone. [source] Differential gene expression in senescing leaves of two silver birch genotypes in response to elevated CO2 and tropospheric ozonePLANT CELL & ENVIRONMENT, Issue 6 2010SARI KONTUNEN-SOPPELA ABSTRACT Long-term effects of elevated CO2 and O3 concentrations on gene expression in silver birch (Betula pendula Roth) leaves were studied during the end of the growing season. Two birch genotypes, clones 4 and 80, with different ozone growth responses, were exposed to 2× ambient CO2 and/or O3 in open-top chambers (OTCs). Microarray analyses were performed after 2 years of exposure, and the transcriptional profiles were compared to key physiological characteristics during leaf senescence. There were genotypic differences in the responses to CO2 and O3. Clone 80 exhibited greater transcriptional response and capacity to alter metabolism, resulting in better stress tolerance. The gene expression patterns of birch leaves indicated contrasting responses of senescence-related genes to elevated CO2 and O3. Elevated CO2 delayed leaf senescence and reduced associated transcriptional changes, whereas elevated O3 advanced leaf senescence because of increased oxidative stress. The combined treatment demonstrated that elevated CO2 only temporarily alleviated the negative effects of O3. Gene expression data alone were insufficient to explain the O3 response in birch, and additional physiological and biochemical data were required to understand the true O3 sensitivity of these clones. [source] The global distribution of infant mortality: a subnational spatial viewPOPULATION, SPACE AND PLACE (PREVIOUSLY:-INT JOURNAL OF POPULATION GEOGRAPHY), Issue 3 2008Adam Storeygard Abstract We describe the compilation of a spatially explicit data-set detailing infant mortality rates in over 10,000 national and subnational units worldwide, benchmarked to the year 2000. Although their resolution is highly variable, subnational data are available for countries representing over 90% of the non-OECD population. Concentration of global infant deaths is higher than implied by national data alone. Assigning both national and subnational data to map grid cells so that they may be easily integrated with other geographical data, we generate infant mortality rates for environmental regions, including biomes and coastal zones, by continent. Rates for these regions also show striking refinements from the use of the higher resolution data. Possibilities and limitations for related work are discussed. Copyright © 2008 John Wiley & Sons, Ltd. [source] FORECASTING MANUFACTURING OUTPUT GROWTH USING FIRM-LEVEL SURVEY DATATHE MANCHESTER SCHOOL, Issue 4 2005JAMES MITCHELL Traditionally forecasts of macroeconomic aggregates are extracted from prospective qualitative survey data by relating official data on the aggregate to both the proportion of survey respondents who are ,optimists' and the proportion who are ,pessimists'. But there is no reason to focus on these proportions to the exclusion of other possible means of aggregating and quantifying the underlying panel of respondent or firm-level survey responses. Accordingly in this paper we show how the panel of firm-level responses underlying these proportions can be exploited to derive forecasts of (aggregate) manufacturing output growth that do not lose information that may be contained in the pattern of individual responses. An application using firm-level prospective survey data from the Confederation of British Industry shows that the forecasts of manufacturing output growth derived using these ,disaggregate' methods mark an improvement over the so-called ,aggregate' methods based on use of the proportions data alone. [source] Light detection and ranging (lidar) in the Witham Valley, Lincolnshire: an assessment of new remote sensing techniquesARCHAEOLOGICAL PROSPECTION, Issue 4 2006Simon Crutchley Abstract Airborne light detection and ranging (lidar) allows the identification and accurate recording of upstanding features on the ground to sub-metre accuracy. The technique has previously been tested in areas of known high monument density such as the Stonehenge World Heritage Site with exciting results, but it is also proving useful in less spectacular areas. This paper will look at some recent work carried out by the Aerial Survey Team at English Heritage concentrating on an area in the Witham Valley, east of Lincoln in the east of England. The area has recently been covered by an archaeological aerial survey project as part of the National Mapping Programme; examining the lidar data for the same area has revealed some interesting results. Lidar clearly has potential for recording certain site types and especially in highlighting relationships between sites in the broader landscape, but there are limitations with the standard off the shelf data due to issues of spatial resolution. The study also makes clear the importance of not using lidar data alone, but ensuring that it is part of an examination of all readily available sources. Copyright © 2006 English Heritage. NMR. [source] MAD phasing using the (Ta6Br12)2+ cluster: a retrospective studyACTA CRYSTALLOGRAPHICA SECTION D, Issue 5 2008Oliwia Pasternak The crystal structure of cytokinin-specific binding protein (CSBP) containing four independent molecules with 4 × 155 = 620 residues in the asymmetric unit of the P64 unit cell has been solved by three-wavelength MAD using 1.8,Å resolution data recorded from a crystal derivatized with the dodecabromohexatantalum cation (Ta6Br12)2+. The diffraction data contained a very strong anomalous signal (allowing successful phasing even using peak SAD data alone) despite the fact that the five (Ta6Br12)2+ clusters found in the asymmetric unit have low occupancy (about 0.3). The derivative structure has been successfully refined to R = 0.158, providing interesting details on the geometry of the (Ta6Br12)2+ cluster, its interactions with the protein and on the backsoaking of a cytokinin ligand that was originally part of a CSBP,cytokinin complex in the native crystals used for (Ta6Br12)2+ derivatization. A simulation analysis of the phasing power of the (Ta6Br12)2+ ions at artificially imposed resolution limits shows that it is not possible to resolve the individual Ta atoms if the dmin limit of the data is higher than 2.9,Å. Additionally, for successful Ta identification the (Ta6Br12)2+ complex should be specifically bound and ordered. Good binding at the protein surface is facilitated by the presence of acidic groups, indicating higher pH buffer conditions to be preferable. In addition, the water channels in the crystal should be sufficiently wide (at least 11,Å) to allow free diffusion of the (Ta6Br12)2+ ions on soaking. A retrospective look at the initial molecular-replacement calculations provides interesting insights into how the peculiar packing mode and strong bias of the molecular-replacement-phased electron-density maps had hindered successful solution of the structure by this method. [source] Linking ecological function to species composition in ecological restoration: Seed removal by ants in recreated woodlandAUSTRAL ECOLOGY, Issue 7 2009BORIS LOMOV Abstract Evaluations of ecological restoration typically focus on associating measures of structural properties of ecosystems (e.g. species diversity) with time since restoration efforts commenced. Such studies often conclude a failure to achieve restoration goals without examining functional performance of the organism assemblages in question. We compared diversity and composition of ant assemblages and the rates of seed removal by ants in pastures, 4- to 10-year old revegetated areas and remnants of Cumberland Plain Woodland, and an endangered ecological community in Sydney, Australia. Ant assemblages of forest remnant sites had significantly higher species richness, significantly different species composition and a more complex functional group structure in comparison with ant assemblages of pasture and revegetated sites, which did not differ significantly. However, the rates of seed removal by ants in revegetated sites were similar to those in forest remnants, with the rates in pasture sites being significantly lower. Approximately, one-third of all ant species were observed to remove seeds. Forest remnant sites had significantly different assemblages of seed removing ant species from those in pasture and revegetated sites. These results demonstrate that similar ant assemblages of unrestored and restored areas can function differently, depending on habitat context. Evaluation of restoration success by quantifying ecosystem structure and function offers more insights into ecosystem recovery than reliance on structural data alone. [source] Perdeuteration, purification, crystallization and preliminary neutron diffraction of an ocean pout type III antifreeze proteinACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 4 2009Isabelle Petit-Haertlein The highly homologous type III antifreeze protein (AFP) subfamily share the capability to inhibit ice growth at subzero temperatures. Extensive studies by X-ray crystallography have been conducted, mostly on AFPs from polar fishes. Although interactions between a defined flat ice-binding surface and a particular lattice plane of an ice crystal have now been identified, the fine structural features underlying the antifreeze mechanism still remain unclear owing to the intrinsic difficulty in identifying H atoms using X-ray diffraction data alone. Here, successful perdeuteration (i.e. complete deuteration) for neutron crystallographic studies of the North Atlantic ocean pout (Macrozoarces americanus) AFP in Escherichia coli high-density cell cultures is reported. The perdeuterated protein (AFP D) was expressed in inclusion bodies, refolded in deuterated buffer and purified by cation-exchange chromatography. Well shaped perdeuterated AFP D crystals have been grown in D2O by the sitting-drop method. Preliminary neutron Laue diffraction at 293,K using LADI-III at ILL showed that with a few exposures of 24,h a very low background and clear small spots up to a resolution of 1.85,Å were obtained using a `radically small' perdeuterated AFP D crystal of dimensions 0.70 × 0.55 × 0.35,mm, corresponding to a volume of 0.13,mm3. [source] The strategic leadership of complex practice: opportunities and challengesCHILD ABUSE REVIEW, Issue 5 2010Tony Morrison Abstract This paper addresses the issue of how strategic-level partnerships, such as Local Safeguarding Children Boards, know about and learn from practice. The death of Baby Peter in Haringey exposed the dangers of reliance on numerical performance data alone to inform leaders about the true state of practice. The drivers for, and impact of, regulatory, media and political pressures on front-line practice and partnership behaviour are discussed with reference to the rise of organisational risk management and ,rule-based' responses (Munro, 2009). These are exacerbated by an overload of negative data about child protection systems which results in contagious ,attention cascades' which lead to over-simplification of complex issues and the rush to quick-fix solutions. This results in compliance-based responses designed to avoid ,blame', based on individualistic analyses of complex situations. Under these conditions, ,learning', such as from serious case reviews, can become regressive (how to avoid future culpability) rather than progressive (how to improve knowledge skills and practice). It is argued that understanding and improving practice require strategic partnerships to have engaged with front-line staff in order to access practice narratives as well as performance numbers, and to achieve an accurate and systemic analysis of the state of practice and how it can be improved. This calls for collective forms of knowing and reflecting and the paper concludes by describing examples. Copyright © 2010 John Wiley & Sons, Ltd. [source] Mitochondrial genome data alone are not enough to unambiguously resolve the relationships of Entognatha, Insecta and Crustacea sensu lato (Arthropoda)CLADISTICS, Issue 6 2004Stephen L. Cameron An analysis of the relationships of the major arthropod groups was undertaken using mitochondrial genome data to examine the hypotheses that Hexapoda is polyphyletic and that Collembola is more closely related to branchiopod crustaceans than insects. We sought to examine the sensitivity of this relationship to outgroup choice, data treatment, gene choice and optimality criteria used in the phylogenetic analysis of mitochondrial genome data. Additionally we sequenced the mitochondrial genome of an archaeognathan, Nesomachilis australica, to improve taxon selection in the apterygote insects, a group poorly represented in previous mitochondrial phylogenies. The sister group of the Collembola was rarely resolved in our analyses with a significant level of support. The use of different outgroups (myriapods, nematodes, or annelids + mollusks) resulted in many different placements of Collembola. The way in which the dataset was coded for analysis (DNA, DNA with the exclusion of third codon position and as amino acids) also had marked affects on tree topology. We found that nodal support was spread evenly throughout the 13 mitochondrial genes and the exclusion of genes resulted in significantly less resolution in the inferred trees. Optimality criteria had a much lesser effect on topology than the preceding factors; parsimony and Bayesian trees for a given data set and treatment were quite similar. We therefore conclude that the relationships of the extant arthropod groups as inferred by mitochondrial genomes are highly vulnerable to outgroup choice, data treatment and gene choice, and no consistent alternative hypothesis of Collembola's relationships is supported. Pending the resolution of these identified problems with the application of mitogenomic data to basal arthropod relationships, it is difficult to justify the rejection of hexapod monophyly, which is well supported on morphological grounds. © The Willi Hennig Society 2004. [source] Response rate and nonresponse bias in a questionnaire survey of dentistsCOMMUNITY DENTISTRY AND ORAL EPIDEMIOLOGY, Issue 1 2005Peter Parashos Abstract , Objectives:, (a) To report on response rate and nonresponse bias of a questionnaire survey of dentists. (b) To make recommendations for future questionnaire survey research in dentistry. Methods:, A questionnaire was mailed to a stratified systematic sample of 908 Australian dentists. The strategy included three mailings, a final telephonic contact, university stationery, paid reply envelopes and personalized correspondence. Nonresponse bias was assessed by comparing responses to a simple ,yes/no' question from each contact (late responders), and by comparing demographic information (nonresponders). Results:, The response rate achieved was 87% and there was no evidence of nonresponse bias based on practice location or year of graduation. The cumulative proportions of ,yes/no' responses essentially remained constant after each contact, but significantly more late responders answered in the negative to the test question than did early responders. The telephonic contact aided in the identification of nonparticipants and ineligible units. Conclusions:, The current survey indicates that differences in data between early and nonresponders can occur despite there being no demographic differences. Therefore, assessment of nonresponse bias based on demographic data alone would seem to be insufficient. Questionnaire survey research must first be based on sound sampling techniques, and then on achieving as high a response rate as possible using the many incentives available. [source] | |||||||||||||||||||||||||