Showing papers by "University of Portsmouth published in 2007"

The Fifth Data Release of the Sloan Digital Sky Survey

Abstract: This paper describes the Fifth Data Release (DR5) of the Sloan Digital Sky Survey (SDSS). DR5 includes all survey quality data taken through 2005 June and represents the completion of the SDSS-I project (whose successor, SDSS-II, will continue through mid-2008). It includes five-band photometric data for 217 million objects selected over 8000 deg^2 and 1,048,960 spectra of galaxies, quasars, and stars selected from 5713 deg^2 of that imaging data. These numbers represent a roughly 20% increment over those of the Fourth Data Release; all the data from previous data releases are included in the present release. In addition to "standard" SDSS observations, DR5 includes repeat scans of the southern equatorial stripe, imaging scans across M31 and the core of the Perseus Cluster of galaxies, and the first spectroscopic data from SEGUE, a survey to explore the kinematics and chemical evolution of the Galaxy. The catalog database incorporates several new features, including photometric redshifts of galaxies, tables of matched objects in overlap regions of the imaging survey, and tools that allow precise computations of survey geometry for statistical investigations.

Loop quantum cosmology of k = 1 FRW models

Abstract: The closed, $k=1$, FRW model coupled to a massless scalar field is investigated in the framework of loop quantum cosmology using analytical and numerical methods. As in the $k=0$ case, the scalar field can be again used as emergent time to construct the physical Hilbert space and introduce Dirac observables. The resulting framework is then used to address a major challenge of quantum cosmology: resolving the big-bang singularity while retaining agreement with general relativity at large scales. It is shown that the framework fulfills this task. In particular, for states which are semiclassical at some late time, the big bang is replaced by a quantum bounce and a recollapse occurs at the value of the scale factor predicted by classical general relativity. Thus, the ``difficulties'' pointed out by Green and Unruh in the $k=1$ case do not arise in a more systematic treatment. As in $k=0$ models, quantum dynamics is deterministic across the deep Planck regime. However, because it also retains the classical recollapse, in contrast to the $k=0$ case one is now led to a cyclic model. Finally, we clarify some issues raised by Laguna's recent work addressed to computational physicists.

Sedimentary basin and detrital zircon record along East Laurentia and Baltica during assembly and breakup of Rodinia

Abstract: Tectonic processes associated with supercontinent cycles result in a variety of basin types, and the isotopic dating of detrital minerals within sedimentary sequences assists palaeogeographical reconstructions. Basins located along the Laurentia–Baltica margin prior to assembly of Rodinia at 1.2–1.0 Ga are dominated by zircon detritus derived from contemporaneous magmatic arcs. Basins formed during assembly are also dominated by zircon detritus with ages similar to that of sediment accumulation, reflecting syn-collisional magmatism and rapid exhumation of the developing Grenville–Sveconorwegian orogen. Post-collision intracratonic basins lack input from syn-depositional magmatism, and are dominated by significantly older detritus derived from the mountain range as well as its foreland. Basins formed during late Neoproterozoic to Cambrian breakup of Rodinia are divisible into two types. Those within the Caledonides lie on the Grenville–Sveconorwegian foreland and incorporate Archaean and Palaeoproterozoic detritus derived from the cratonic interior and Mesoproterozoic detritus derived from the eroded remnants of the orogen. In the Appalachian orogen, such basins are dominated by Mesoproterozoic detritus with older detritus forming only a minor component, suggesting restricted input from the cratonic interior as a result of either the Grenville orogen still forming a drainage divide or the formation of rift shoulders.

FLR: an open-source framework for the evaluation and development of management strategies

Abstract: The FLR framework (Fisheries Library for R) is a development effort directed towards the evaluation of fisheries management strategies. The overall goal is to develop a common framework to facilitate collaboration within and across disciplines (e.g. biological, ecological, statistical, mathematical, economic, and social) and, in particular, to ensure that new modelling methods and software are more easily validated and evaluated, as well as becoming widely available once developed. Specifically, the framework details how to implement and link a variety of fishery, biological, and economic software packages so that alternative management strategies and procedures can be evaluated for their robustness to uncertainty before implementation. The design of the framework, including the adoption of object-orientated programming, its feasibility to be extended to new processes, and its application to new management approaches (e.g. ecosystem affects of fishing), is discussed. The importance of open source for promoting transparency and allowing technology transfer between disciplines and researchers is stressed.

The Crato Fossil Beds of Brazil: Window into an Ancient World

Abstract: This beautifully illustrated 2007 volume describes the entire flora and fauna of the famous Lower Cretaceous Crato Formation of Brazil - one of the world's most important fossil deposits, exhibiting exceptional preservation A wide range of invertebrates and vertebrates are covered, including extended sections on pterosaurs and insects Two chapters are devoted to plants Many of the chapters include descriptions of new species and re-descriptions and appraisals of taxa published in obscure places, rendering them available to a wider audience Fossil descriptions are supported by detailed explanations of the geological history of the deposit and its tectonic setting Drawing on expertise from around the world and specimens from the most important museum collections, this book forms an essential reference for researchers and enthusiasts with an interest in Mesozoic fossils

Intrinsic galaxy alignments from the 2SLAQ and SDSS surveys: luminosity and redshift scalings and implications for weak lensing surveys

Abstract: Correlations between intrinsic shear and the density field on large scales, a potentially important contaminant for cosmic shear surveys, have been robustly detected at low redshifts with bright galaxies in Sloan Digital Sky Survey (SDSS) data. Here we present a more detailed characterization of this effect, which can cause anticorrelations between gravitational lensing shear and intrinsic ellipticity (GI correlations). This measurement uses 36 278 luminous red galaxies (LRGs) from the SDSS spectroscopic sample with 0.15 3σ detections of the effect on large scales (up to 60 h−1 Mpc) for all galaxy subsamples within the SDSS LRG sample; for the 2SLAQ sample, we find a 2σ detection for a bright subsample, and no detection for a fainter subsample. Fitting formulae are provided for the scaling of the GI correlations with luminosity, transverse separation and redshift (for which the 2SLAQ sample, while small, provides crucial constraints due to its longer baseline in redshift). We estimate contamination in the measurement of σ8 for future cosmic shear surveys on the basis of the fitted dependence of GI correlations on galaxy properties. We find contamination to the power spectrum ranging from −1.5 per cent (optimistic) to −33 per cent (pessimistic) for a toy cosmic shear survey using all galaxies to a depth of R = 24 using scales l ≈ 500, though the central value of predicted contamination is −6.5 per cent. This corresponds to a bias in σ8 of Δσ8 = −0.004 (optimistic), −0.02 (central) or −0.10 (pessimistic). We provide a prescription for inclusion of this error in cosmological parameter estimation codes. The principal uncertainty is in the treatment of the L ≤ L blue galaxies, for which we have no detection of the GI signal, but which could dominate the GI contamination if their GI amplitude is near our upper limits. Characterization of the tidal alignments of these galaxies, especially at redshifts relevant for cosmic shear, should be a high priority for the cosmic shear community.

The 2dF-SDSS LRG and QSO survey: QSO clustering and the L-z degeneracy

Abstract: We combine the quasi-stellar object (QSO) samples from the 2dF QSO Redshift Survey (2QZ) and the 2dF-Sloan Digital Sky Survey luminous red galaxy (LRG) and QSO Survey (2dF-SDSS LRG and QSO, hereafter 2SLAQ) in order to investigate the clustering of z∼ 1.5 QSOs and measure the correlation function (ξ). The clustering signal in redshift-space and projected along the sky direction is similar to that previously obtained from the 2QZ sample alone. By fitting functional forms for ξ(σ, π), the correlation function measured along and across the line of sight, we find, as expected, that β, the dynamical infall parameter and Ω0m , the cosmological density parameter, are degenerate. However, this degeneracy can be lifted by using linear theory predictions under different cosmological scenarios. Using the combination of the 2QZ and 2SLAQ QSO data, we obtain: βQSO(z= 1.5) = 0.60+0.14−0.11, Ω0m= 0.25+0.09−0.07 which imply a value for the QSO bias, b(z= 1.4) = 1.5 ± 0.2 . The combination of the 2QZ with the fainter 2SLAQ QSO sample further reveals that QSO clustering does not depend strongly on luminosity at fixed redshift. This result is inconsistent with the expectation of simple 'high peaks' biasing models where more luminous, rare QSOs are assumed to inhabit higher mass haloes. The data are more consistent with models which predict that QSOs of different luminosities reside in haloes of similar mass. By assuming ellipsoidal models for the collapse of density perturbations, we estimate the mass of the dark matter haloes which the QSOs inhabit as ∼3 × 1012 h−1 M⊙ . We find that this halo mass does not evolve strongly with redshift nor depend on QSO luminosity. Assuming a range of relations which relate halo to black hole mass, we investigate how black hole mass correlates with luminosity and redshift, and ascertain the relation between Eddington efficiency and black hole mass. Our results suggest that QSOs of different luminosities may contain black holes of similar mass.

The Work-Related Quality of Life scale for healthcare workers.

Abstract: Title. The Work-Related Quality of Life scale for healthcare workers Aim. This paper is a report of a study to develop and test the psychometric properties of the Work-Related Quality of Life scale for healthcare workers. Background. As problems associated with stress and job satisfaction are evident for healthcare workers and nurses, a reliable tool to assess employees’ quality of working life is required. However, previous research has produced inconsistent factor structures and inadequate psychometric properties for a range of quality of working life measures. This new scale expands the concept of quality of working life by incorporating a broad six-factor structure derived from a theoretical review of the field. Method. We used data from a 2003 survey of 953 healthcare workers. Eighty-six per cent of the sample is female and 36% had been employed by the organization for 1–5 years. Approximately 50% of workers were employed full-time. Findings. Both exploratory and confirmatory factor analysis using split-half data sets produced a good fit and a reliable 23-item, six-factor measurement model of Work-Related Quality of Life. The factors generated were labelled: Job and Career Satisfaction, General Well-Being, Home–Work Interface, Stress at Work, Control at Work and Working Conditions. Conclusion. The Work-Related Quality of Life measure is one of the most succinct yet psychometrically valid and reliable Quality of Working Life scales in the literature. We propose that it can appropriately be used in healthcare organizations to assess quality of working life. Further research is required to refine the instrument and assess its applicability to other areas.

Regulation of myofibroblast transdifferentiation by DNA methylation and MeCP2: implications for wound healing and fibrogenesis

Abstract: Myofibroblasts are critical cellular elements of wound healing generated at sites of injury by transdifferentiation of resident cells. A paradigm for this process is conversion of hepatic stellate cells (HSC) into hepatic myofibroblasts. Treatment of HSC with DNA methylation inhibitor 5-aza-2'-deoxycytidine (5-azadC) blocked transdifferentiation. 5-azadC also prevented loss of IkappaBalpha and PPARgamma expression that occurs during transdifferentiation to allow acquisition of proinflammatory and profibrogenic characteristics. ChIP analysis revealed IkappaBalpha promoter is associated with transcriptionally repressed chromatin that converts to an active state with 5-azadC treatment. The methyl-CpG-binding protein MeCP2 which promotes repressed chromatin structure is selectively detected in myofibroblasts of diseased liver. siRNA knockdown of MeCP2 elevated IkappaBalpha promoter activity, mRNA and protein expression in myofibroblasts. MeCP2 interacts with IkappaBalpha promoter via a methyl-CpG-dependent mechanism and recruitment into a CBF1 corepression complex. We conclude that MeCP2 and DNA methylation exert epigenetic control over hepatic wound healing and fibrogenesis.

Eicosapentaenoic acid (EPA, an omega‐3 fatty acid from fish oils) for the treatment of cancer cachexia

Abstract: Background- Cancer cachexia is a distressing weight loss syndrome commonly seen in advanced cancer patients. It is associated with reduced quality of life and shorter survival time. Eicosapentaenoic acid (EPA) is a long chain polyunsaturated fatty acid found naturally in some fish which has been used to decrease weight loss, promote weight gain and increase survival times in patients affected with cancer cachexia. Objectives - To evaluate the effectiveness and safety of EPA in relieving symptoms associated with the cachexia syndrome in patients with advanced cancer. Search strategy - Studies were sought through an extensive search of a range of electronic databases. Hand searching was conducted on selected journals and reference lists as well as contact made with investigators, manufacturers and experts. The most recent electronic search was conducted in February 2005. Selection criteria - Studies were included in the review if they assessed oral EPA compared with placebo or control in randomised controlled trials of patients with advanced cancer and either a clinical diagnosis of cachexia or self-reported weight loss of 5% or more. Data collection and analysis - Both methodological quality evaluation of potential trials and data extraction were conducted by two independent review authors. Main results - Five trials (involving 587 participants) met the inclusion criteria. Three trials compared EPA at different doses with placebo with two outcomes, nutritional status and adverse events comparable across two of the three included trials. In addition, two trials compared different doses of EPA with an active matched control. It was possible to compare the outcomes of weight, quality of life and adverse events across these two trials. There were insufficient data to define the optimal dose of EPA. Authors' conclusions -There were insufficient data to establish whether oral EPA was better than placebo. Comparisons of EPA combined with a protein energy supplementation versus a protein energy supplementation (without EPA) in the presence of an appetite stimulant (Megestrol Acetate) provided no evidence that EPA improves symptoms associated with the cachexia syndrome often seen in patients with advanced cancer.

Historical GIS: structuring, mapping and analysing geographies of the past

Abstract: The last 10 years have seen a sudden rise in interest in the use of Geographical Information Systems (GIS) in historical research. This has led to a field that has become known as `historical GIS'. This development started in the more quantitative ends of the discipline but has spread to encompass qualitative research as well. Interest in historical GIS is not restricted to researchers who would previously have regarded themselves as historical geographers, but has in fact led to an increased awareness of the importance of geography from across the discipline of history. This paper introduces historical GIS and critically evaluates how it is affecting the practice of historical geography.

Cues to Deception and Ability to Detect Lies as a Function of Police Interview Styles

Abstract: In Experiment 1, we examined whether three interview styles used by the police, accusatory, information-gathering and behaviour analysis, reveal verbal cues to deceit, measured with the Criteria-Based Content Analysis (CBCA) and Reality Monitoring (RM) methods. A total of 120 mock suspects told the truth or lied about a staged event and were interviewed by a police officer employing one of these three interview styles. The results showed that accusatory interviews, which typically result in suspects making short denials, contained the fewest verbal cues to deceit. Moreover, RM distinguished between truth tellers and liars better than CBCA. Finally, manual RM coding resulted in more verbal cues to deception than automatic coding of the RM criteria utilising the Linguistic Inquiry and Word Count (LIWC) software programme. In Experiment 2, we examined the effects of the three police interview styles on the ability to detect deception. Sixty-eight police officers watched some of the videotaped interviews of Experiment 1 and made veracity and confidence judgements. Accuracy scores did not differ between the three interview styles; however, watching accusatory interviews resulted in more false accusations (accusing truth tellers of lying) than watching information-gathering interviews. Furthermore, only in accusatory interviews, judgements of mendacity were associated with higher confidence. We discuss the possible danger of conducting accusatory interviews.

The 2dF-SDSS LRG and QSO Survey: the LRG 2-point correlation function and redshift-space distortions

Abstract: We present a clustering analysis of luminous red galaxies (LRGs) using nearly 9000 objects from the final, three-year catalogue of the 2dF-SDSS LRG and QSO (2SLAQ) Survey. We measure the redshift-space two-point correlation function, ξ(s) and find that, at the mean LRG redshift of shows the characteristic downturn at small scales (1 h−1 Mpc) expected from line-of-sight velocity dispersion. We fit a double power law to ξ(s) and measure an amplitude and slope of s0 = 17.3+2.5−2.0 h−1 Mpc, γ = 1.03 ± 0.07 at small scales (s 4.5 h−1 Mpc). In the semiprojected correlation function, wp(σ), we find a simple power law with γ = 1.83 ± 0.05 and r0 = 7.30 ± 0.34 h−1 Mpc fits the data in the range 0.4 < σ < 50 h−1 Mpc, although there is evidence of a steeper power law at smaller scales. A single power law also fits the deprojected correlation function ξ(r), with a correlation length of r0 = 7.45 ± 0.35 h−1 Mpc and a power-law slope of γ = 1.72 ± 0.06 in the 0.4 < r < 50 h−1 Mpc range. But it is in the LRG angular correlation function that the strongest evidence for non-power-law features is found where a slope of γ = −2.17 ± 0.07 is seen at 1 < r < 10 h−1 Mpc with a flatter γ = −1.67 ± 0.07 slope apparent at r 1 h−1 Mpc scales. We use the simple power-law fit to the galaxy ξ(r), under the assumption of linear bias, to model the redshift-space distortions in the 2D redshift-space correlation function, ξ(σ, π). We fit for the LRG velocity dispersion, wz, the density parameter, Ωm and β(z), where β(z) = Ω0.6m/b and b is the linear bias parameter. We find values of wz = 330 km s−1, Ωm = 0.10+0.35−0.10 and β = 0.40 ± 0.05. The low values for wz and β reflect the high bias of the LRG sample. These high-redshift results, which incorporate the Alcock–Paczynski effect and the effects of dynamical infall, start to break the degeneracy between Ωm and β found in low-redshift galaxy surveys such as 2dFGRS. This degeneracy is further broken by introducing an additional external constraint, which is the value β(z = 0.1) = 0.45 from 2dFGRS, and then considering the evolution of clustering from z 0 to zLRG 0.55. With these combined methods we find Ωm(z = 0) = 0.30 ± 0.15 and β(z = 0.55) = 0.45 ± 0.05. Assuming these values, we find a value for b(z = 0.55) = 1.66 ± 0.35. We show that this is consistent with a simple ����high-peak’ bias prescription which assumes that LRGs have a constant comoving density and their clustering evolves purely under gravity.

Clustering analyses of 300,000 photometrically classified quasars. I. Luminosity and redshift evolution in quasar bias

Abstract: Using 300,000 photometrically classified quasars, by far the largest quasar sample ever used for such analyses,we study the redshift and luminosity evolution of quasar clustering on scales of 50 h-1 kpc to 20 h-1 Mpc from redshifts of z 0:75-2:28. We parameterize our clustering amplitudes using realistic dark matter models and find that a ΛCDM power spectrum provides a superb fit to our data with a redshift-averaged quasar bias of bz =1:40Q = 2:41±0:08 (P 99.6%using our data set alone, increasing to >99.9999% if stellar contamination is not explicitly parameterized. We measure the quasar classification efficiency across our full sample as a = 95:6 ± 4:41:9 %, a star-quasar separation comparable to the star-galaxy separation in many photometric studies of galaxy clustering.We derive the mean mass of the dark matter halos hosting quasars as MDMH = (5:2 ± 0:6) x 1012 h-1 M⊙. At z ∼ 1:9 we find a 1.5 σ deviation from luminosity independent quasar clustering; this suggests that increasing our sample size by a factor of ∼1.8 could begin to constrain any luminosity dependence in quasar bias at z ∼ 2. Our results agree with recent studies of quasar environments at z < 0:4, which detected little luminosity dependence to quasar clustering on proper scales ≳50 h-1 kpc. At z < 1:6,our analysis suggests that bQ is constant with luminosity to within ΔbQ ∼ 0:6, and that, for g < 21, angular quasar autocorrelation measurements are unlikely to have sufficient statistical power at z ≲ 1:6 to detect any luminosity dependence in quasars’ clustering.

Dynamical modelling of luminous and dark matter in 17 Coma early-type galaxies

Abstract: Dynamical models for 17 early-type galaxies in the Coma cluster are presented. The galaxy sample consists of flattened, rotating as well as non-rotating early-types including cD and S0 galaxies with luminosities between MB = 18.79 and MB = 22.56. Kinematical long-slit observations cover at least the major and minor axis and extend to 1 4 reff. Axisymmetric Schwarzschild models are used to derive stellar mass-tolight ratios and dark halo parameters. In every galaxy the best fit with dark matter matches the data better than the best fit without. The statistical significance is over 95 percent for 8 galaxies, around 90 percent for 5 galaxies and for four galaxies it is not significant. For the highly significant cases systematic deviations between observed and modelled kinematics are clearly seen; for the remaining galaxies differences are more statistical in nature. Best-fit models contain 10-50 percent dark matter inside the half-light radius. The central dark matter density is at least one order of magnitude lower than the luminous mass density, independent of the assumed dark matter density profile. The central phase-space density of dark matter is often orders of magnitude lower than in the luminous component, especially when the halo core radius is large. The orbital system of the stars along the major-axis is slightly dominated by radial motions. Some galaxies show tangential anisotropy along the minor-axis, which is correlated with the minor-axis Gauss-Hermite coefficientH4. Changing the balance between data-fit and regularisation constraints does not change the reconstructed mass structure significantly: model anisotropies tend to strengthen if the weight on regularisation is reduced, but the general property of a galaxy to be radially or tangentially anisotropic, respectively, does not change. This paper is aimed to set the basis for a subsequent detailed analysis of luminous and dark matter scaling relations, orbital dynamics and stellar populations.

Can the 12-item General Health Questionnaire be used to measure positive mental health?

Abstract: Background. Well-being is an important determinant of health and social outcomes. Measures of positive mental health states are needed for population-based research. The 12-item General Health Questionnaire (GHQ-12) has been widely used in many settings and languages, and includes positively and negatively worded items. Our aim was to test the hypothesis that the GHQ-12 assesses both positive and negative mental health and that these domains are independent of one another. Method. Exploratory (EFA) and confirmatory (CFA) factor analyses were conducted using data from the British Household Panel Survey (BHPS) and the Health Survey for England (HSE). Regression models were used to assess whether associations with individual and household characteristics varied across positive and negative mental health dimensions. We also explored higher-level variance in these measures, between electoral wards. Results. We found a consistent, replicable factor structure in both datasets. EFA results indicated a two-factor solution, and CFA demonstrated that this was superior to a one-factor model. These factors correspond to ‘symptoms of mental disorder’ and ‘positive mental health’. Further analyses demonstrated independence of these factors in associations with age, gender, employment status, poor housing and household composition. Statistically significant ward-level variance was found for symptoms of mental disorder but not positive mental health. Conclusions. The GHQ-12 measures both positive and negative aspects of mental health, and although correlated, these dimensions have some independence. The GHQ-12 could be used to measure positive mental health in population-based research.

Multiple field inflation

Abstract: Inflation offers a simple model for very early evolution of our universe and the origin of primordial perturbations on large scales. Over the last 25 years we have become familiar with the predictions of single-field models, but inflation with more than one light scalar field can alter preconceptions about the inflationary dynamics and our predictions for the primordial perturbations. I will discuss how future observational data could distinguish between inflation driven by one field, or many fields. As an example, I briefly review the curvation as an alternative to the inflaton scenario for the origin of structure.

Dissolved iron in the vicinity of the Crozet Islands, Southern Ocean

Abstract: The annual phytoplankton bloom occurring north of the Crozet Plateau provides a rare opportunity to examine the hypothesis that natural iron fertilization can alleviate high-nutrient low-chlorophyll (HNLC) conditions normally associated with the Southern Ocean. Therefore, during CROZet natural iron bloom and EXport experiment (CROZEX), a large multidisciplinary study performed between November 2004 and January 2005, measurements of total dissolved iron (DFe⩽0.2 μm) were made on seawater from around the islands and atmospheric iron deposition estimated from rain and aerosol samples. DFe concentrations were determined by flow injection analysis with N,N-dimethyl-p-phenylenediamine dihydrochloride (DPD) catalytic spectrophotometric detection. DFe concentrations varied between 0.086 and 2.48 nM, with low values in surface waters. Enrichment of dissolved iron (>1 nM) at close proximity to the islands suggests that the plateau and the associated sediments are a source of iron. Waters farther north also appear to be affected by this input of coastal and shelf origin, although dissolved iron concentrations decrease as a function of distance to the north of the plateau with a gradient of ∼0.07 nM km−1 at the time of sampling. Using lateral and vertical diffusion coefficients derived from Ra isotope profiles and also estimates of atmospheric inputs, it was then possible to estimate a DFe concentration of ∼0.55 nM to the north of the islands prior to the bloom event, which is sufficient to initiate the bloom, the lateral island source being the largest component. A similar situation is observed for other Sub-Antarctic Islands such as Kerguelen, South Georgia, that supply dissolved iron to their surrounding waters, thus enhancing chlorophyll concentrations.

A Cross-species Comparison of Facial Morphology and Movement in Humans and Chimpanzees Using the Facial Action Coding System (FACS)

Abstract: A comparative perspective has remained central to the study of human facial expressions since Darwin’s [(1872/1998). The expression of the emotions in man and animals (3rd ed.). New York: Oxford University Press] insightful observations on the presence and significance of cross-species continuities and species-unique phenomena. However, cross-species comparisons are often difficult to draw due to methodological limitations. We report the application of a common methodology, the Facial Action Coding System (FACS) to examine facial movement across two species of hominoids, namely humans and chimpanzees. FACS [Ekman & Friesen (1978). Facial action coding system. CA: Consulting Psychology Press] has been employed to identify the repertoire of human facial movements. We demonstrate that FACS can be applied to other species, but highlight that any modifications must be based on both underlying anatomy and detailed observational analysis of movements. Here we describe the ChimpFACS and use it to compare the repertoire of facial movement in chimpanzees and humans. While the underlying mimetic musculature shows minimal differences, important differences in facial morphology impact upon the identification and detection of related surface appearance changes across these two species.

Loop quantum cosmology and the k=-1 Robertson-Walker model

Abstract: The loop quantization of the negatively curved $k=\ensuremath{-}1$ Robertson-Walker model poses several technical challenges. We show that the issues can be overcome and a successful quantization is possible that extends the results of the $k=0$, $+1$ models in a natural fashion. We discuss the resulting dynamics and show that for a universe consisting of a massless scalar field, a bounce is predicted in the backward evolution in accordance with the results of the $k=0$, $+1$ models. We also show that the model predicts a vacuum repulsion in the high curvature regime that would lead to a bounce even for matter with vanishing energy density. We finally comment on the inverse volume modifications of loop quantum cosmology and show that, as in the $k=0$ model, the modifications depend sensitively on the introduction of a length scale which a priori is independent of the curvature scale or a matter energy scale.

Sociology and the body: classical traditions and new agendas

Abstract: Reflecting developments in consumer culture, the politics of social movements, public health policy, and medical technologies, the body has since the early 1980s become one of the most popular and ...

Minimum mass–radius ratio for charged gravitational objects

Abstract: We rigorously prove that for compact charged general relativistic objects there is a lower bound for the mass–radius ratio. This result follows from the same Buchdahl type inequality for charged objects, which has been extensively used for the proof of the existence of an upper bound for the mass–radius ratio. The effect of the vacuum energy (a cosmological constant) on the minimum mass is also taken into account. Several bounds on the total charge, mass and the vacuum energy for compact charged objects are obtained from the study of the Ricci scalar invariants. The total energy (including the gravitational one) and the stability of the objects with minimum mass–radius ratio is also considered, leading to a representation of the mass and radius of the charged objects with minimum mass–radius ratio in terms of the charge and vacuum energy only.

Turnover intention and preparedness for change: exploring leader-member exchange and occupational self-efficacy as antecedents of two employability predictors

Abstract: Purpose – “Turnover intention” is defined as an employee's intention to voluntarily change jobs or companies. The purpose of this paper is to set “turnover intention” in relation to “preparedness for change”. The former relates to the change of jobs or companies, the latter to employees' willingness to change their current workplace. Both phenomena relate to employability, i.e. an employee's adaptability to changing internal (i.e. the current employer) and external labour market demands. The main aim of this paper is to compare both phenomena and identify antecedents of employability, namely, leader‐member exchange (LMX) and occupational self‐efficacy.Design/methodology/approach – A questionnaire study was conducted in two samples of German and Dutch employees.Findings – Results indicate that the two concepts (turnover intention, preparedness for change) are, to some extent, related and show, to some extent, similar relationships to the antecedents.Research limitations/implications – In both samples, self...

Elevated plasma interleukin-6 levels in trained male triathletes following an acute period of intense interval training.

Abstract: The aim of the present study was to investigate possible changes in the plasma IL-6 levels, subjective reporting of sources and symptoms of stress and the innate immune system in response to an acute period of intensified run training in highly trained endurance athletes. Eight healthy endurance trained male subjects (mean +/- SD age 23 +/- 2 years, VO(2max) 64.8 +/- 2.6 ml kg(-1) min(-1), mass 77.1 +/- 2.9 kg) completed the study which took place over a 4 week period. In weeks 2 and 3, in addition to their normal endurance training, subjects completed interval-training run sessions on three successive days. Saliva and venous blood samples were taken at the end of each week. Blood samples were analysed for leukocyte counts; neutrophil function; plasma IL-6; creatine kinase activity; and cortisol. Symptoms and sources of stress were assessed by questionnaire. Plasma IL-6 and creatine kinase activity were elevated following intensified training. Neutrophil function was reduced but total leukocyte and neutrophil counts, plasma cortisol and salivary IgA remained unchanged. There was a worsening in symptoms of stress despite there being no significant change in the sources of stress during intensified training. In conclusion, an acute period of intensified training can induce a suppression of the innate immune system and a chronic elevation in IL-6. This was associated with an increase in fatigue and generalised malaise which lends support to the recent cytokine theories of unexplained, underperformance syndrome.