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Terms modified by Plausible Selected AbstractsEffect of Gender on Communication of Health Information to Older AdultsJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 4 2006Jennifer L. Dearborn BA OBJECTIVES: To examine the effect of gender on three key elements of communication with elderly individuals: effectiveness of the communication, perceived relevance to the individual, and effect of gender-stereotyped content. DESIGN: Survey. SETTING: University of Connecticut Health Center. PARTICIPANTS: Thirty-three subjects (17 female); aged 69 to 91 (mean±standard deviation 82±5.4). MEASUREMENTS: Older adults listened to 16 brief narratives randomized in order and by the sex of the speaker (Narrator Voice). Effectiveness was measured according to ability to identify key features (Risks), and subjects were asked to rate the relevance (Plausibility). Number of Risks detected and determinations of plausibility were analyzed according to Subject Gender and Narrator Voice. Narratives were written for either sex or included male or female bias (Neutral or Stereotyped). RESULTS: Female subjects identified a significantly higher number of Risks across all narratives (P=.01). Subjects perceived a significantly higher number of Risks with a female Narrator Voice (P=.03). A significant Voice-by-Stereotype interaction was present for female-stereotyped narratives (P=.009). In narratives rated as Plausible, subjects detected more Risks (P=.02). CONCLUSION: Subject Gender influenced communication effectiveness. A female speaker resulted in identification of more Risks for subjects of both sexes, particularly for Stereotyped narratives. There was no significant effect of matching Subject Gender and Narrator Voice. This study suggests that the sex of the speaker influences the effectiveness of communication with older adults. These findings should motivate future research into the means by which medical providers can improve communication with their patients. [source] Abductive Diagnosis Using Time-Objects: Criteria for the Evaluation of SolutionsCOMPUTATIONAL INTELLIGENCE, Issue 1 2001Elpida T. Keravnou Diagnostic problem solving aims to account for, or explain, a malfunction of a system (human or other). Any plausible potential diagnostic solution must satisfy some minimum criteria relevant to the application. Often there will be several plausible solutions, and further criteria will be required to select the "best" explanation. Expert diagnosticians may employ different, complex criteria at different stages of their reasoning. These criteria may be combinations of some more primitive criteria, which therefore should be represented separately and explicitly to permit their flexible and transparent combined usage. In diagnostic reasoning there is a tight coupling between the formation of potential solutions and their evaluation. This is the essence of abductive reasoning. This article presents an abductive framework for diagnostic problem solving. Time-objects, an association of a property and an existence, are used as the representation formalism and a number of primitive, general evaluation criteria into which time has been integrated are defined. Each criterion provides an intuitive yardstick for evaluating the space of potential solutions. The criteria can be combined as appropriate for particular applications to define plausible and best explanations. The central principle is that when time is diagnostically significant, it should be modeled explicitly to enable a more accurate formulation and evaluation of diagnostic solutions. The integration of time and primitive evaluation criteria is illustrated through the Skeletal Dysplasias Diagnostician (SDD) system, a diagnostic expert system for a real-life medical domain. SDD's notions of plausible and best explanation are reviewed so as to show the difficulties in formalizing such notions. Although we illustrate our work by medical problems, it has been motivated by consideration of problems in a number of other domains (fermentation monitoring, air and ground traffic control, power distribution) and is intended to be of wide applicability. [source] Wrinkling Coarse Meshes on the GPUCOMPUTER GRAPHICS FORUM, Issue 3 2006J. Loviscach The simulation of complex layers of folds of cloth can be handled through algorithms which take the physical dynamics into account. In many cases, however, it is sufficient to generate wrinkles on a piece of garment which mostly appears spread out. This paper presents a corresponding fully GPU-based, easy-to-control, and robust method to generate and render plausible and detailed folds. This simulation is generated from an animated mesh. A relaxation step ensures that the behavior remains globally consistent. The resulting wrinkle field controls the lighting and distorts the texture in a way which closely simulates an actually deformed surface. No highly tessellated mesh is required to compute the position of the folds or to render them. Furthermore, the solution provides a 3D paint interface through which the user may bias the computation in such a way that folds already appear in the rest pose. Categories and Subject Descriptors (according to ACM CCS): I.3.7 [Computer Graphics]: Animation, I.3.7 [Computer Graphics]: Color, shading, shadowing, and texture [source] Association of criminal convictions between family members: Effects of siblings, fathers and mothersCRIMINAL BEHAVIOUR AND MENTAL HEALTH, Issue 2 2009Marieke van de Rakt Background,Crime runs in families. Previous research has shown the existence of intergenerational transmission of criminal behaviour. Aim,The aim of the present study was to investigate the extent to which variation in criminal convictions may be explained by the criminality of siblings and by the intergenerational transmission of criminal behaviour. Method,Data from the Dutch Criminal Career and Life-course Study (CCLS) were used to analyse cross-tabulations and to conduct multi-level logistic regression analyses. Results,The results indicate that criminal convictions of other family members are indeed correlated with individual conviction risk. The criminal history of siblings is most strongly correlated with the convictions of focal respondents. Results furthermore show that parental convictions only account modestly for the association of criminal convictions between siblings. Conclusions,These findings indicate that a direct influence between siblings is plausible, providing support for learning or imitation theories. Copyright © 2009 John Wiley & Sons, Ltd. [source] MANDATORY HIV TESTING IN PREGNANCY: IS THERE EVER A TIME?DEVELOPING WORLD BIOETHICS, Issue 1 2008RUSSELL ARMSTRONG ABSTRACT Despite recent advances in ways to prevent transmission of HIV from a mother to her child during pregnancy, infants continue to be born and become infected with HIV, particularly in southern Africa where HIV prevalence is the highest in the world. In this region, emphasis has shifted from voluntary HIV counselling and testing to routine testing of women during pregnancy. There have also been proposals for mandatory testing. Could mandatory testing ever be an option, even in high-prevalence settings? Many previous examinations of mandatory testing have dealt with it in the context of low HIV prevalence and a well-resourced health care system. In this discussion, different assumptions are made. Within this context, where mandatory testing may be a strategy of last resort, the objections to it are reviewed. Special attention is paid in the discussion to the entrenched vulnerability of women in much of southern Africa and how this contributes to both HIV prevalence and ongoing challenges for preventing HIV transmission during pregnancy. While mandatory testing is ethically plausible, particularly when coupled with guaranteed access to treatment and care, the discussion argues that the moment to employ this strategy has not yet come. Many barriers remain for pregnant women in terms of access to testing, treatment and care, most acutely in the southern African setting, despite the presence of national and international human rights instruments aimed at empowering women and removing such barriers. While this situation persists, mandatory HIV testing during pregnancy cannot be justified. [source] Agricultural Productivity Growth and Poverty AlleviationDEVELOPMENT POLICY REVIEW, Issue 4 2001Xavier Irz How important is agricultural growth to poverty reduction? This article first sets out the theoretical reasons for expecting agricultural growth to reduce poverty. Several plausible and strong arguments apply - including the creation of jobs on the land, linkages from farming to the rest of the rural economy, and a decline in the real cost of food for the whole economy - but the degree of impact is in all cases qualified by particular circumstances. Hence, the article deploys a cross-country estimation of the links between agricultural yield per unit area and measures of poverty. This produces strong confirmation of the hypothesised linkages. It is unlikely that there are many other development interventions capable of reducing the numbers in poverty so effectively. [source] Desmoplastic round cell tumor of childhood: Can cytology with immunocytochemistry serve as an alternative for tissue diagnosis?DIAGNOSTIC CYTOPATHOLOGY, Issue 6 2005Dr Brijal Dave M.D. Abstract There are limited reports on the cytology of desmoplastic small round cell tumors (DSRCT). Fine needle aspiration biopsy (FNAB) findings in seven aspirates from four cases of histologically and immunohistochemically confirmed cases were analyzed with the main intention of ascertaining if cytological diagnosis of DSRCT is possible. Also assessed were the immunocytochemistry(ICC) findings in these cases. The basic cytological impression was that of a cohesive small round cell tumor. Nuclei showed granular chromatin with grooves, nuclear molding and inconspicuous nucleoli. Stromal fragments were noted in all four cases. In two cases, awareness of cytological features in the appropriate clinical context led to a suggestion of the diagnosis of DSRCT on cytology itself. ICC on destained smears showed positivity for cytokeratin, epithelial membrane antigen (EMA), desmin and WT-1 in two cases. In conclusion, given the right clinical setting, a cytological diagnosis of DSRCT is plausible and in conjunction with ICC may help in documenting the polyphenotypic nature and thereby confirming the diagnosis. Diagn. Cytopathol. 2005;32:330,335. © 2005 Wiley-Liss, Inc. [source] Effects of species and habitat positional errors on the performance and interpretation of species distribution modelsDIVERSITY AND DISTRIBUTIONS, Issue 4 2009Patrick E. Osborne Abstract Aim, A key assumption in species distribution modelling is that both species and environmental data layers contain no positional errors, yet this will rarely be true. This study assesses the effect of introduced positional errors on the performance and interpretation of species distribution models. Location, Baixo Alentejo region of Portugal. Methods, Data on steppe bird occurrence were collected using a random stratified sampling design on a 1-km2 pixel grid. Environmental data were sourced from satellite imagery and digital maps. Error was deliberately introduced into the species data as shifts in a random direction of 0,1, 2,3, 4,5 and 0,5 pixels. Whole habitat layers were shifted by 1 pixel to cause mis-registration, and the cumulative effect of one to three shifted layers investigated. Distribution models were built for three species using three algorithms with three replicates. Test models were compared with controls without errors. Results, Positional errors in the species data led to a drop in model performance (larger errors having larger effects , typically up to 10% drop in area under the curve on average), although not enough for models to be rejected. Model interpretation was more severely affected with inconsistencies in the contributing variables. Errors in the habitat layers had similar although lesser effects. Main conclusions, Models with species positional errors are hard to detect, often statistically good, ecologically plausible and useful for prediction, but interpreting them is dangerous. Mis-registered habitat layers produce smaller effects probably because shifting entire layers does not break down the correlation structure to the same extent as random shifts in individual species observations. Spatial autocorrelation in the habitat layers may protect against species positional errors to some extent but the relationship is complex and requires further work. The key recommendation must be that positional errors should be minimised through careful field design and data processing. [source] The braincase of the chondrichthyan Doliodus from the Lower Devonian Campbellton Formation of New Brunswick, CanadaACTA ZOOLOGICA, Issue 2009John Maisey Abstract The braincase of the late Lower Devonian (Emsian) chondrichthyan Doliodus is described for the first time. Its postorbital process is extended ventrally and probably enclosed part of the infraorbital sensory canal, as in some placoderms. Doliodus has a shark-like dentition, but its upper anterior tooth files were supported by the internasal cartilage of the braincase, not by the palatoquadrates. Modern selachian jaws and dentitions are not representative of primitive crown-group gnathostomes because they display a mixture of conserved and derived character states. Separation of the palatoquadrates by the internasal cartilage is probably a primitive condition for crown-group gnathostomes. Continuity of the upper dental arcade across the ethmoid region may represent a synapomorphy of chondrichthyans and some acanthodians (the condition is not found in placoderms or osteichthyans). Exclusion of the arcade from the ethmoid region is probably apomorphic within elasmobranchs. Doliodus has curious bar-like, paired subcranial ridges ending posteriorly at the hyomandibular articulation. These superficially resemble visceral arch infrapharyngohyals fused to the floor of the braincase, adding circumstantial palaeontological support to the old proposal that parts of visceral arches may be incorporated into the gnathostome braincase, although it seems more plausible that they formed in the lateral margins of the embryonic parachordal or hypotic lamina. [source] The origins of the theophoric week in the Germanic languagesEARLY MEDIEVAL EUROPE, Issue 4 2007Philip Shaw The Germanic terms for the days of the week that contain the names of Germanic deities are often taken to result from Romano-Germanic interactions in the fourth century AD. Yet this need not be the case: the linguistic arguments underpinning this view are not decisive. A reassessment of these names suggests that an early medieval process of transfer in scholarly Christian contexts may be equally, if not more, plausible. [source] Accounting for uncertainty in DEMs from repeat topographic surveys: improved sediment budgetsEARTH SURFACE PROCESSES AND LANDFORMS, Issue 2 2010Joseph M. Wheaton Abstract Repeat topographic surveys are increasingly becoming more affordable, and possible at higher spatial resolutions and over greater spatial extents. Digital elevation models (DEMs) built from such surveys can be used to produce DEM of Difference (DoD) maps and estimate the net change in storage terms for morphological sediment budgets. While these products are extremely useful for monitoring and geomorphic interpretation, data and model uncertainties render them prone to misinterpretation. Two new methods are presented, which allow for more robust and spatially variable estimation of DEM uncertainties and propagate these forward to evaluate the consequences for estimates of geomorphic change. The first relies on a fuzzy inference system to estimate the spatial variability of elevation uncertainty in individual DEMs while the second approach modifies this estimate on the basis of the spatial coherence of erosion and deposition units. Both techniques allow for probabilistic representation of uncertainty on a cell-by-cell basis and thresholding of the sediment budget at a user-specified confidence interval. The application of these new techniques is illustrated with 5 years of high resolution survey data from a 1,km long braided reach of the River Feshie in the Highlands of Scotland. The reach was found to be consistently degradational, with between 570 and 1970,m3 of net erosion per annum, despite the fact that spatially, deposition covered more surface area than erosion. In the two wetter periods with extensive braid-plain inundation, the uncertainty analysis thresholded at a 95% confidence interval resulted in a larger percentage (57% for 2004,2005 and 59% for 2006,2007) of volumetric change being excluded from the budget than the drier years (24% for 2003,2004 and 31% for 2005,2006). For these data, the new uncertainty analysis is generally more conservative volumetrically than a standard spatially-uniform minimum level of detection analysis, but also produces more plausible and physically meaningful results. The tools are packaged in a wizard-driven Matlab software application available for download with this paper, and can be calibrated and extended for application to any topographic point cloud (x,y,z). Copyright © 2009 John Wiley & Sons, Ltd. [source] The Relationship Between Left Ventricular Shape and QT Interval DispersionECHOCARDIOGRAPHY, Issue 8 2002F.A.C.C., Kishore J. Harjai M.D. Left ventricular geometry is suspected to affect heterogeneity of myocardial repolarization; therefore, it is plausible but unproven that increased sphericity of the left ventricle is associated with greater QT interval dispersion. In 60 patients with dilated cardiomyopathy with left ventricular ejection fraction , 30%, we found that spherical distortion of the left ventricle was associated with increased QT dispersion, implying increased heterogeneity of myocardial repolarization. [source] Rediscovering MDMA (ecstasy): the role of the American chemist Alexander T. ShulginADDICTION, Issue 8 2010Udo Benzenhöfer ABSTRACT Aims Alexander T. Shulgin is widely thought of as the ,father' of +/,3,4-methylenedioxymethamphetamine (MDMA). This paper re-assesses his role in the modern history of this drug. Methods We analysed systematically Shulgin's original publications on MDMA, his publications on the history of MDMA and his laboratory notebook. Results According to Shulgin's book PIHKAL (1991), he synthesized MDMA in 1965, but did not try it. In the 1960s Shulgin also synthesized MDMA-related compounds such as 3,4-methylenedioxyamphetamine (MDA), 3-methoxy-4,5-methylenedioxyamphetamine (MMDA) and 3,4-methylenedioxyethylamphetamine (MDE), but this had no impact on his rediscovery of MDMA. In the mid-1970s Shulgin learned of a ,special effect' caused by MDMA, whereupon he re-synthesized it and tried it himself in September 1976, as confirmed by his laboratory notebook. In 1977 he gave MDMA to Leo Zeff PhD, who used it as an adjunct to psychotherapy and introduced it to other psychotherapists. Conclusion Shulgin was not the first to synthesize MDMA, but he played an important role in its history. It seems plausible that he was so impressed by its effects that he introduced it to psychotherapist Zeff in 1977. This, and the fact that in 1978 he published with David Nichols the first paper on the pharmacological action of MDMA in humans, explains why Shulgin is sometimes (erroneously) called the ,father' of MDMA. [source] Tooth row counts, vicariance, and the distribution of the sand tiger shark Carcharias taurusECOGRAPHY, Issue 5 2003Luis O. Lucifora Geographic variation in tooth row counts among sand tiger sharks Carcharias taurus (Chondrichthyes), from the SW Atlantic, NW Atlantic and the East China Sea is analyzed in this paper. We found significant differences between sand tigers from the SW Atlantic (Southern Hemisphere population) and each of the other two (Northern Hemisphere) regions in the number of upper lateral tooth rows, and between individuals from the SW Atlantic and the East China Sea in the total number of upper tooth rows. Sand tiger sharks from the two Northern Hemisphere populations did not differ in any of the studied variables. Our results agree with comparisons of vertebral counts between sand tiger sharks from Southern and Northern Hemispheres. Both lines of evidence suggest that Southern and Northern Hemisphere populations of C. taurus were isolated to a larger extent than populations of the Northern Hemisphere. The fossil record of the genus Carcharias begins in the Early Cretaceous and C. taurus is certainly known since the Late Miocene. During the Miocene, the Tethys Sea separating northern and southern land masses was still present and it provided a continuous temperate shallow sea that could allow dispersal of sand tiger sharks along Northern Hemisphere seas. Independent observations on the distribution and evolutionary history of the genera Myripristis, Neoniphon, Sargocentron and Aphanius, and genetic studies on the temperate shark genus Mustelus that indicate a close relationship between the Indo-Pacific M. manazo and the Mediterranean M. asterias suggest that this hypothesis is plausible and deserves to be tested. [source] PRICE AND EFFICIENCY EFFECTS OF TAXES AND SUBSIDIES FOR AUSTRALIAN HOUSINGECONOMIC PAPERS: A JOURNAL OF APPLIED ECONOMICS AND POLICY, Issue 2 2007PETER ABELSON This paper quantifies the major subsidies and taxes that affect housing, the impacts on house prices and housing consumption, and the efficiency effects. Private housing receives an estimated net subsidy of $6.3 billion per annum. Most of this subsidy accrues to homeowners, who as a group receive about an 8% subsidy on imputed gross rentals. The rental sector receives a subsidy of approximately 0.4% of rents. On plausible (unitary elasticity) demand and supply assumptions, the homeowner subsidy increases all housing prices by about 2% and total housing consumption by about 2%, with the rise in consumption by home owners more than offsetting the fall in consumption by renters. The housing subsidy produces an estimated deadweight loss from expenditure on renovations of about $100 million per annum. However, contrary to previous work, the paper finds that the housing subsidy produces welfare gains from expenditure on new housing in the order of $187 million a year. This arises because the subsidy offsets the over-regulated supply of new housing. Transaction taxes on housing have a separate deadweight loss of $375 million per annum. Also, the unequal treatment of homeowners and renters creates a small annual deadweight loss. [source] Maternal control of cold and desiccation tolerance in eggs of the band-legged ground cricket Dianemobius nigrofasciatus in relation to embryonic diapauseENTOMOLOGICAL RESEARCH, Issue 1 2008Shin G. GOTO Abstract Cold and desiccation tolerance was investigated in the eggs of the band-legged ground cricket Dianemobius nigrofasciatus in relation to embryonic diapause. Diapause eggs were more tolerant to both desiccation and cold than non-diapause eggs. In addition, diapause-destined eggs on day zero (0,12 h after being laid) already showed high tolerance to these stresses before entering diapause. This clearly indicates that stress tolerance, like diapause, is controlled by photoperiod, but is not directly associated with diapause itself. Because the acquisition of stress tolerance predates the onset of diapause, it is plausible that diapause programming during some period before the onset of diapause is involved in the acquisition of stress tolerance. Weights and sizes were nearly identical in short-day and long-day eggs until day five. Sorbitol, a major sugar alcohol in eggs of D. nigrofasciatus, was accumulated at the same level in short-day and long-day eggs on days zero and five. These results indicate that the surface-to-volume ratio as well as the accumulation of sugar alcohol is not involved in the acquisition of stress tolerance. Maternal factors are clearly involved in the acquisition of stress tolerance in D. nigrofasciatus eggs, but the physiological mechanisms underlying the tolerance are still unclear. [source] Tobacco smoke carcinogens and breast cancerENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 2-3 2002Stephen S. Hecht Abstract Cigarette smoking is an established cause of a variety of cancer types, but its role in breast cancer etiology is not clear. In this report, the potential role of cigarette smoke carcinogens as causes of human breast cancer is evaluated. Of over 60 known carcinogens in tobacco smoke, several are known to induce mammary tumors in laboratory animals: benzo[a]pyrene (B[a]P), dibenzo[a,l]pyrene (DB[a,l]P), 2-toluidine, 4-aminobiphenyl, 2-amino-3-methylimidazo[4,5- f]quinoline (IQ), 2-amino-1-methyl-6-phenylimidazo[4,5- b]pyridine (PhIP), 1,3-butadiene, isoprene, nitromethane, ethylene oxide, and benzene. Studies in humans demonstrate that tobacco constituents can reach breast tissue. The uptake and metabolic activation of mammary carcinogens such as polycyclic aromatic hydrocarbons (PAHs) and 4-aminobiphenyl are frequently higher in smokers than in nonsmokers. Although it is likely that specific mammary carcinogens in tobacco smoke can reach breast tissue, evidence is lacking at the present time. Some PAHs present in cigarette smoke can be metabolized to sterically hindered diol epoxides, which are potent mammary carcinogens. Thus, compounds such as benzo[c]phenanthrene (B[c]P), not classically considered to be a strong carcinogen in rodents, could nevertheless be metabolized in humans to diol epoxides carcinogenic to the breast. Collectively, the link between smoking and breast cancer is plausible but has been difficult to establish, probably because of the low carcinogen dose. Environ. Mol. Mutagen. 39:119,126, 2002. © 2002 Wiley-Liss, Inc. [source] Mechanism of DNA damage by cadmium and interplay of antioxidant enzymes and agentsENVIRONMENTAL TOXICOLOGY, Issue 2 2007Veera L. D. Badisa Abstract Cadmium is an environmental toxicant, which causes cancer in different organs. It was found that it damages DNA in the various tissues and cultured cell lines. To investigate the mechanism of DNA damage, we have studied the effect of cadmium-induced DNA damage in plasmid pBR322 DNA, and the possible ameliorative effects of antioxidative agents under in vitro conditions. It was observed that cadmium alone did not cause DNA damage. However, it caused DNA damage in the presence of hydrogen peroxide, in a dose dependent manner, because of production of hydroxyl radicals. Findings from this study show the conversion of covalently closed circular double-stranded pBR 322 DNA to the open circular and linear forms of DNA when treated with 10 ,M cadmium and various concentrations of H2O2. The conversion was due to nicking in DNA strands. The observed rate of DNA strand breakage was dependent on H2O2 concentration, temperature, and time. Metallothionein I failed to prevent cadmium-induced DNA nicking in the presence of H2O2. Of the two antioxidant enzymes (catalase and superoxide dismutase) studied, only catalase conferred significant (50,60%) protection. EDTA and DMSO exhibited protection similar to catalase, while mannitol showed only about 20% protection against DNA damage. Ethyl alcohol failed to ameliorate cadmium-induced DNA strands break. From this study, it is plausible to infer that cadmium in the presence of hydrogen peroxide causes DNA damage probably by the formation of hydroxyl ions. These results may indicate that cadmium in vivo could play a major role in the DNA damage induced by oxidative stress. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 144,151, 2007. [source] An image warping approach to spatio-temporal modellingENVIRONMETRICS, Issue 8 2005Sofia Aberg Abstract In this article we present a spatio-temporal dynamic model that can be realized using image warping. Image warping is a non-linear deformation which maps every point in one image plane to a point in another image plane. Using thin-plate splines, these deformations are defined by how a small set of points is mapped, making the method computationally tractable. In our case the dynamics of the process is modelled by thin-plate spline deformations and how they vary in time. Thus we make no assumption of stationarity in time. Finding the deformation between two images in the space,time series is a trade-off between a good match of the images and a smooth, physically plausible, deformation. This is formulated as a penalized likelihood problem, where the likelihood measures how good the match is and the penalty comes from a prior model on the deformation. The dynamic model we suggest can be used to make forecasts and also to estimate the uncertainties associated with these. An introduction to image warping and thin-plate splines is given as well as an application where the methodology is applied to the problem of nowcasting radar precipitation. Copyright © 2005 John Wiley & Sons, Ltd. [source] Dream recall frequency and sleep quality of patients with restless legs syndromeEUROPEAN JOURNAL OF NEUROLOGY, Issue 2 2001M. Schredl The present study investigated the dream recall frequency and the pattern of influencing factors of patients with restless legs syndrome in comparison with healthy controls. The patients' dream recall frequency did not differ from that of healthy controls. Dream recall, however, was negatively associated with the number of periodic leg movements with arousal (PLMAI). Subjective estimates of sleep quality or feeling of being refreshed in the morning, on the other hand, did not correlate with the PLMAI index. Whereas subjective sleep parameters were related to dream recall frequency in healthy controls, no substantial relationships were found in the patient group, except for the positive correlation between sleep latency and dream recall frequency. The results of the present study can not be interpreted as clear evidence for the arousal,retrieval model of dream recall; it seems plausible that other factors, e.g. the functional state of the brain, are of importance in explaining dream recall in this patient group. [source] Constitutionalism and Dissonances: Has Europe Paid Off Its Debt to Functionalism?EUROPEAN LAW JOURNAL, Issue 3 2009Marco Dani This impression seems confirmed by the recent Presidency Conclusions of the European Council which, although salvaging many important solutions contained in the Constitutional Treaty, explicitly sanction that ,the constitutional concept . . . is abandoned'. In the light of this context, what role could the constitutional scholarship play? How to make sense of a polity in which the claims of constitutionalism as a form of power are politically unappealing though legally plausible? This article tries to respond to these questions by reaffirming functionalism as a valid analytical and normative perspective in facing the current constitutional reality of European integration. The analytical value associated with functionalism is evidenced by testing against the current context of the EU legal framework the accounts for EU constitutionalism which postulate functional equivalence between the EU and the Member States. The normative potential of functionalism, then, is discussed by arguing that there may be a value worth preserving in a degree of functional discrepancy between the EU and state constitutionalism and, notably, that the transformative and civilising dividend inherent in functionalism could still be exploited, at least in certain areas of EU policy making. Finally, the article suggests that the difficulties in accounting for EU constitutionalism in the light of state-centred constitutional theory could be regarded as symptoms of European integration marking a moment in the theoretical evolution of constitutionalism. [source] ASSORTATIVE MATING FOR FITNESS AND THE EVOLUTION OF RECOMBINATIONEVOLUTION, Issue 7 2006Alistair Blachford Abstract To understand selection on recombination, we need to consider how linkage disequilibria develop and how recombination alters these disequilibria. Any factors that development of disequilbria, including nonrandom mating, can potentially change selectio on recombination. Assortative mating is known to affect linkage disequilbria but its effect on the evolution of recombination have not been previously studied. Given that assortative arise indirectly via a number of biologically realistic scenarios, it is plausible that weak assortative mating occurs across a diverse set of taxa. Using a modifier model, we examine how assortative mating for fitness affects the evolution of recombination under two evolutionary scenarios: selective sweeps and mutation-selection balance. We find there is no net effect of assortative mating during a selective sweep. In contrast, assortative mating could have a large effect on recombination when deleterious alleles are maintained at mutation-selection balance but only if assortative mating is sufficiently strong. Upon considering reasonable values for the number of loci affecting fitness components, the strength of selection, and the mutation rate, we conclude that the correlation in fitness between mates is unlikely to be sufficiently high for assortative mating to affect the evolution of recombination in most species. [source] THE ADAPTIVE SIGNIFICANCE OF TEMPERATURE-DEPENDENT SEX DETERMINATION: EXPERIMENTAL TESTS WITH A SHORT-LIVED LIZARDEVOLUTION, Issue 10 2005Daniel A. Warner Abstract Why is the sex of many reptiles determined by the temperatures that these animals experience during embryogenesis, rather than by their genes? The Charnov-Bull model suggests that temperature-dependent sex determination (TSD) can enhance maternal fitness relative to genotypic sex determination (GSD) if offspring traits affect fitness differently for sons versus daughters and nest temperatures either determine or predict those offspring traits. Although potential pathways for such effects have attracted much speculation, empirical tests largely have been precluded by logistical constraints (i.e., long life spans and late maturation of most TSD reptiles). We experimentally tested four differential fitness models within the Charnov-Bull framework, using a short-lived, early-maturing Australian lizard (Amphibolurus muricatus) with TSD. Eggs from wild-caught females were incubated at a range of thermal regimes, and the resultant hatchlings raised in large outdoor enclosures. We applied an aromatase inhibitor to half the eggs to override thermal effects on sex determination, thus decoupling sex and incubation temperature. Based on relationships between incubation temperatures, hatching dates, morphology, growth, and survival of hatchlings in their first season, we were able to reject three of the four differential fitness models. First, matching offspring sex to egg size was not plausible because the relationship between egg (offspring) size and fitness was similar in the two sexes. Second, sex differences in optimal incubation temperatures were not evident, because (1) although incubation temperature influenced offspring phenotypes and growth, it did so in similar ways in sons versus daughters, and (2) the relationship between phenotypic traits and fitness was similar in the two sexes, at least during preadult life. We were unable to reject a fourth model, in which TSD enhances offspring fitness by generating seasonal shifts in offspring sex ratio: that is, TSD allows overproduction of daughters (the sex likely to benefit most from early hatching) early in the nesting season. In keeping with this model, hatching early in the season massively enhanced body size at the beginning of the first winter, albeit with a significant decline in probability of survival. Thus, the timing of hatching is likely to influence reproductive success in this short-lived, early maturing species; and this effect may well differ between the sexes. [source] DIFFERENTIAL PERFORMANCE AMONG LDH-B GENOTYPES IN RANA LESSONAE TADPOLESEVOLUTION, Issue 5 2000Hansjürg Hotz Abstract The European pool frog, Rana lessonae, is widely polymorphic for two common alleles (b, e) at the lactate dehydrogenase-B (LDH-B) locus. We compared fitness-related larval life-history traits among LDH-B genotypes, which originated from segregation in heterozygous parents, in an artificial pond experiment where tadpoles of R. lessonae from a Swiss population were raised together with tadpoles of the hemiclonal hybrid R. esculenta at two densities. In R. lessonae, LDH-B e/e homozygotes at each density had a higher proportion of metamorphs among survivors, reached metamorphosis earlier, and were heavier at metamorphosis than b/b homozygotes; b/e heterozygotes had intermediate values. That e/e individuals were superior to b/b in both time to and mass at metamorphosis is surprising because these two life-history traits are thought to reflect a performance trade-off; e/e genotypes apparently compensated for shorter time to metamorphosis by a higher growth rate. The two alleles showed the same performance ranking when combined in hybrids with a R. ridibunda allele: When R. esculenta from Swiss populations reared in the same ponds had received the e allele rather than the b allele from their R. lessonae parent, they reached metamorphosis earlier, but did not differ in mass at metamorphosis. The degree of linkage disequilibrium in the source population of the eight R. lessonae used as parents of the R. lessonae tadpoles is unknown, so we cannot exclude the possibility that the performance differences are caused by some anonymous tightly linked gene, rather than the LDH-B locus, that constitutes the genomically localized target of natural selection. A causal involvement of LDH-B is plausible, nevertheless, because this enzyme takes part in the central energy-metabolizing processes and has been reported to underlie fitness differences in other animals; also, differential performance of LDH-B genotypes has been observed in R. lessonae larvae from another population. The present results suggest strong directional selection for allele e; the sum of available data, including an independent laboratory experiment, suggests that partial environment-dependent overdominance combined with balancing selection favoring e/e homozygotes under some and b/b homozygotes under other conditions may be partially responsible for the broad maintenance of the LDH-B polymorphism in R. lessonae. [source] CALORIE RESTRICTION AND AGING: A LIFE-HISTORY ANALYSISEVOLUTION, Issue 3 2000Daryl P. Shanley Abstract., The disposable soma theory suggests that aging occurs because natural selection favors a strategy in which fewer resources are invested in somatic maintenance than are necessary for indefinite survival. However, laboratory rodents on calorie-restricted diets have extended life spans and retarded aging. One hypothesis is that this is an adaptive response involving a shift of resources during short periods of famine away from reproduction and toward increased somatic maintenance. The potential benefit is that the animal gains an increased chance of survival with a reduced intrinsic rate of senescence, thereby permitting reproductive value to be preserved for when the famine is over. We describe a mathematical life-history model of dynamic resource allocation that tests this idea. Senescence is modeled as a change in state that depends on the resources allocated to maintenance. Individuals are assumed to allocate the available resources to maximize the total number of descendants. The model shows that the evolutionary hypothesis is plausible and identifies two factors, both likely to exist, that favor this conclusion. These factors are that survival of juveniles is reduced during periods of famine and that the organism needs to pay an energetic "overhead" before any litter of offspring can be produced. If neither of these conditions holds, there is no evolutionary advantage to be gained from switching extra resources to maintenance. The model provides a basis to evaluate whether the life-extending effects of calorie-restriction might apply in other species, including humans. [source] Probability modelling and statistical analysis of damage in the lower wing skins of two retired B-707 aircraftFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 8 2001D. G. Harlow A plausible mechanistically based probability model for localized pitting corrosion and subsequent fatigue crack nucleation and growth is used to analyse tear-down inspection data from two retired B-707 aircraft that had been in commercial service for about 24 and 30 years. Sections of the left-hand lower wing skins from these aircraft had been previously disassembled and inspected optically at 20× magnification. The inspections were augmented by metallographic examinations for the lower time aircraft. The evolution of damage in the fastener holes is estimated by using reasonable values for the localized corrosion and fatigue crack growth rates, statistically estimated from laboratory data. The primary loading, assumed to be the mean design load, is considered to be from ground,air,ground wing bending cycles, augmented by ,average' gust loading, only. The encouraging agreement between the estimated probability of occurrence and the observed distribution of multiple hole,wall cracks attests to the efficacy of the approach and its relevancy to airworthiness assessment and fleet life management. [source] Atrial natriuretic peptide-dependent photolabeling of a regulatory ATP-binding site on the natriuretic peptide receptor-AFEBS JOURNAL, Issue 21 2005Simon Joubert The natriuretic peptide receptor-A (NPR-A) is composed of an extracellular ligand-binding domain, a transmembrane-spanning domain, a kinase homology domain (KHD) and a guanylyl cyclase domain. Because the presence of ATP or adenylylimidodiphosphate reduces atrial natriuretic peptide (ANP) binding and is required for maximal guanylyl cyclase activity, a direct interaction of ATP with the receptor KHD domain is plausible. Therefore, we investigated whether ATP interacts directly with a binding site on the receptor by analyzing the binding of a photoaffinity analog of ATP to membranes from human embryonic kidney 293 cells expressing the NPR-A receptor lacking the guanylyl cyclase moiety (,GC). We demonstrate that this receptor (NPR-A-,GC) can be directly labeled by 8-azido-3,-biotinyl-ATP and that labeling is highly increased following ANP treatment. The mutant receptor ,KC, which does not contain the KHD, is not labeled. Photoaffinity labeling of the NPR-A-,GC is reduced by 50% in the presence of 550 µm ATP, and competition curve fitting studies indicate a Hill slope of 2.2, suggestive of cooperative binding. This approach demonstrates directly that the interaction of ANP with its receptor modulates the binding of ATP to the KHD, probably through a conformational change in the KHD. In turn, this conformational change is essential for maximal activity. In addition, the ATP analog, 8-azido-adenylylimidodiphosphate, inhibits guanylyl cyclase activity but increases ANP binding to the extracellular domain. These results suggest that the KHD regulates ANP binding and guanylyl cyclase activity independently. [source] A steady-state modeling approach to validate an in vivo mechanism of the GAL regulatory network in Saccharomyces cerevisiaeFEBS JOURNAL, Issue 20 2004Malkhey Verma Cellular regulation is a result of complex interactions arising from DNA,protein and protein,protein binding, autoregulation, and compartmentalization and shuttling of regulatory proteins. Experiments in molecular biology have identified these mechanisms recruited by a regulatory network. Mathematical models may be used to complement the knowledge-base provided by in vitro experimental methods. Interactions identified by in vitro experiments can lead to the hypothesis of multiple candidate models explaining the in vivo mechanism. The equilibrium dissociation constants for the various interactions and the total component concentration constitute constraints on the candidate models. In this work, we identify the most plausible in vivo network by comparing the output response to the experimental data. We demonstrate the methodology using the GAL system of Saccharomyces cerevisiae for which the steady-state analysis reveals that Gal3p neither dimerizes nor shuttles between the cytoplasm and the nucleus. [source] Karyotypic similarity identified by multiplex-FISH relates four prostate adenocarcinoma cell lines: PC-3, PPC-1, ALVA-31, and ALVA-41GENES, CHROMOSOMES AND CANCER, Issue 4 2001Marileila Varella-Garcia Recently developed molecular cytogenetic techniques for karyotyping are providing new and important insights regarding the chromosomal changes that occur in solid tumors. We used multiplex-FISH to analyze four adenocarcinoma cell lines, PC-3, PPC-1, ALVA-31, and ALVA-41, in which the characterization of a large number of rearranged chromosomes was partially or substantially inconclusive by G-banding. Although the original descriptions of these lines depict them as distinct entities established from different patients, this study demonstrates that these four lines share numerous, highly rearranged chromosomes, strongly supporting the conclusion that they are derived from the same patient material. Our analysis indicates that PPC-1, ALVA-31, and ALVA-41 were derived from PC-3 through mechanisms involving clonal progression represented by sequential changes and clonal diversion represented by differing patterns of changes. Extensive cellular heterogeneity was detected in all four lines, and most rearrangements included segments derived from multiple chromosomes. Each line also showed a set of unique derivative chromosomes. However, a limited number of metaphase cells (approximately 10) was analyzed for each line, and numerous single-cell abnormalities were detected in all of them. Therefore, it is plausible that the number of clonal, shared, and/or unique rearrangements has been underestimated. These cell lines have been utilized as models for understanding the biology of prostate cancer and reportedly differ in their cell physiology. Rather than detracting from their value, a complete understanding of the interrelationships of these lines to one another may provide the opportunity to define the molecular changes that have led to their individual malignant phenotypes. © 2001 Wiley-Liss, Inc. [source] Neoproterozoic ,snowball Earth' glaciations and the evolution of altruismGEOBIOLOGY, Issue 4 2007R. A. BOYLE ABSTRACT We hypothesize that a demographic and ecological effect of Neoproterozoic ,snowball Earth' glaciations was to increase the fitness of group-level traits and consequently the likelihood of the evolution of macroscopic form. Extreme and repeated founder effects raised genetic relatedness , and therefore the influence of kin selection on the individuals within a group. This was permissive for the evolution of some highly costly altruistic traits, including those for macroscopic differentiation. In some eukaryotic species, the harsh and fluctuating abiotic conditions made a macroscopic physiology advantageous, perhaps necessary, for collective survival. This caused population-wide group viability selection, whereby non-altruist ,cheat' genotypes killed the groups they were in, and therefore themselves, by reaching fixation. Furthermore, dispersal between refugia would reach zero under anything near a ,hard snowball', which would protect altruists at high local frequency from the influx of cheats from neighbouring groups. We illustrate our hypothesis analytically and with a simple spatial model. We show how removal of between-group dispersal, in a population with initial between-group variation in cheat frequency, causes the relative frequency of altruists to increase while the population as a whole decreases in size, as a result of group death caused by cheat invasion. This may be of particular relevance to animal multicellularity because irreversible differentiation (highly altruistic in that it imposes a high fitness cost on the individual cell) is more prevalent than in other multicellular eukaryotes. The relevance of our hypothesis should be scaled by any future consensus on the severity of snowball Earth, but it is theoretically plausible that global-scale glaciations had a systematic influence on the level of selection during Earth history. [source] | |||||||||||||||||||||||||||||||||||||