Dilatant normal faulting in jointed cohesive rocks: a physical model study

Dilatant faults often form in rocks containing pre-existing joints, but the effects of joints on fault segment linkage and fracture connectivity are not well understood. We present an analogue modeling study using cohesive powder with pre-formed joint sets in the upper layer, varying the angle between joints and a rigid basement fault. We analyze interpreted map-view photographs at maximum displacement for damage zone width, number of connected joints, number of secondary fractures, degree of segmentation and area fraction of massively dilatant fractures. Particle imaging velocimetry provides insight into the deformation history of the experiments and illustrates the localization pattern of fault segments. Results show that with increasing angle between joint-set and basement-fault strike the number of secondary fractures and the number of connected joints increase, while the area fraction of massively dilatant fractures shows only a minor increase. Models without pre-existing joints show far lower area fractions of massively dilatant fractures while forming distinctly more secondary fractures

Evolution of a highly dilatant fault zone in the grabens of Canyonlands National Park, Utah, USA - Integrating fieldwork, ground-penetrating radar and airborne imagery analysis

Abstract. The grabens of Canyonlands National Park are a young and active system of sub-parallel, arcuate grabens, whose evolution is the result of salt movement in the subsurface and a slight regional tilt of the faulted strata. We present results of ground-penetrating radar (GPR) surveys in combination with field observations and analysis of high-resolution airborne imagery. GPR data show intense faulting of the Quaternary sediments at the flat graben floors, implying a more complex fault structure than visible at the surface. Direct measurements of heave and throw at several locations to infer fault dips at depth, combined with observations of primary joint surfaces in the upper 100 m, suggest a highly dilatant fault geometry. Sinkholes observed in the field as well as in airborne imagery give insights in local dilatancy and show where water and sediments are transported underground. Based on correlations of paleosols observed in outcrops and GPR profiles, we argue that either the grabens in Canyonlands National Park are older than previously assumed or that sedimentation rates were much higher in the Pleistocene. This is the final version of the article. It first appeared from Copernicus Publications via http://dx.doi.org/10.5194/se-6-839-2015 The supplement related to this article is available online at http://dx.doi.org/10.5194/se-6-839-2015-supplemen

On the photometric variability of blue supergiants in NGC 300 and its impact on the Flux-weighted Gravity-Luminosity Relationship

We present a study of the photometric variability of spectroscopically confirmed supergiants in NGC 300, comprising 28 epochs extending over a period of five months. We find 15 clearly photometrically variable blue supergiants in a sample of nearly 70 such stars, showing maximum light amplitudes ranging from 0.08 to 0.23 magnitudes in the V band, and one variable red supergiant. We show their light curves, and determine semi-periods for two A2 Ia stars. Assuming that the observed changes correspond to similar variations in the bolometric luminosity, we test for the influence of this variability on the Flux-weighted Gravity--Luminosity Relationship and find a negligible effect, showing that the calibration of this relationship, which has the potential to measure extragalactic distances at the Cepheid accuracy level, is not affected by the stellar photometric variability in any significant way.Comment: 9 pages, 3 figures, 3 tables. Accepted for publication in the Astrophysical Journa

Galactose inhibition of the constitutive transport of hexoses in Saccharomyces cerevisiae

The relationship between the pathways of glucose and galactose utilization in Saccharomyces cerevisiae has been studied. Galactose (which is transported and phosphorylated by inducible systems) is a strong inhibitor of the utilization of glucose, fructose and mannose (which have the same constitutive transport and phosphorylation systems). Conversely, all these three hexoses inhibit the utilization of galactose, though with poor efficiency. These cross-inhibitions only occur in yeast adapted to galactose or in galactose-constitutive mutants. The efficiency of galactose as inhibitor is even greater than the efficiencies of each of the other three hexoses to inhibit the utilization of each other. Phosphorylation is not involved in the inhibition and transport of sugars is the affected step. The cross-inhibitions between galactose and either glucose, fructose or mannose do not implicate utilization of one hexose at the expense of the other, as it occurs in the mutual interactions between the latter three sugars. it seems that, by growing the yeast in galactose, a protein component is synthesized, or alternatively modified, that once bound to either galactose or any one of the other three hexoses (glucose, fructose or mannose), cross-interacts respectively with the constitutive or the inducible transport systems, impairing their function.This work was supported by a grant (PB87-0206) from the DGICYT, Promoción General del Conocimiento.Peer Reviewe

Maladaptive personality traits in adolescence: Psychometric properties of the Personality Diagnostic Questionnaire-4+

AbstractThe Personality Diagnostic Questionnaire-4+ (PDQ-4+) is a self-report used for the assessment of personality disorder traits, however, its psychometric characteristics have yet to be tested in community samples of adolescents. The main goal was to analyze the psychometric properties of the PDQ-4+ scores in a large sample of non-clinical adolescents (N=1,443; M=15.9 years; SD=1.2). The PDQ-4+ scores showed adequate psychometric properties. Reliability of the subscales, incorporating a Likert-type 5-point response format, ranged from .62 to .85. The study of the internal structure at item level revealed that the PDQ-4+ subscales were essentially one-dimensional. Analysis of the internal structure at the subscale level by means of exploratory factor analysis and exploratory structural equation modeling yielded a possible three-dimensional solution. The PDQ-4+ subscales correlated moderately with emotional and behavioural variables measured by the Strengths and Difficulties Questionnaire. The results have clear implications for the understanding of maladaptive personality traits in adolescents

Evaluation of phospholipid transfer protein and cholesteryl ester transfer protein as contributors to the generation of pre beta-high-density lipoproteins

High-density lipoproteins (HDLs) are considered anti-atherogenic because they mediate peripheral cell cholesterol transport to the liver for excretion and degradation. An important step in this reverse cholesterol-transport pathway is the uptake of cellular cholesterol by a specific subclass of small, lipid-poor apolipoprotein A-I particles designated pre beta-HDL. The two lipid-transfer proteins present in human plasma, cholesteryl ester transfer protein (CETP) and phospholipid transfer protein (PLTP), have both been implicated in the formation of pre beta-HDL. In order to investigate the relative contribution of each of these proteins, we used transgenic mouse models. Comparisons were made between human CETP transgenic mice (huCETPtg), human PLTP transgenic mice (huPLTPtg) and mice transgenic for both lipid-transfer proteins (huCETPtg/huPLTPtg). These animals showed elevated plasma levels of CETP activity, PLTP activity or both activities, respectively. We evaluated the generation of pre beta-HDL in mouse plasma by immunoblotting and crossed immuno-electrophoresis. Generation of pre beta-HDL was equal in huCETPtg and wild-type mice. In contrast, in huPLTPtg and huCETPtg/huPLTPtg mice, pre beta-HDL generation was 3-fold higher than in plasma from either wild-type or huCETPtg mice. Our findings demonstrate that, of the two plasma lipid-transfer proteins, PLTP rather than CETP is responsible for the generation of pre beta-HDL. These data support the hypothesis of a role for PLTP in the initial stage of reverse cholesterol transport

Influence of severity and level of injury on the occurrence of complications during the subacute and chronic stage of traumatic spinal cord injury:a systematic review

Objective: Secondary health conditions (SHCs) are long-term complications that frequently occur due to traumatic spinal cord injury (tSCI) and can negatively affect quality of life in this patient population. This study provides an overview of the associations between the severity and level of injury and the occurrence of SHCs in tSCI. Methods: A systematic search was conducted in PubMed and Embase that retrieved 44 studies on the influence of severity and/or level of injury on the occurrence of SHCs in the subacute and chronic phase of tSCI (from 3 months after trauma). The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Results: In the majority of studies, patients with motor-complete tSCI (American Spinal Injury Association [ASIA] Impairment Scale [AIS] grade A or B) had a significantly increased occurrence of SHCs in comparison to patients with motor-incomplete tSCI (AIS grade C or D), such as respiratory and urogenital complications, musculoskeletal disorders, pressure ulcers, and autonomic dysreflexia. In contrast, an increased prevalence of pain was seen in patients with motor-incomplete injuries. In addition, higher rates of pulmonary infections, spasticity, and autonomic dysreflexia were observed in patients with tetraplegia. Patients with paraplegia more commonly suffered from hypertension, venous thromboembolism, and pain. Conclusions: This review suggests that patients with a motor-complete tSCI have an increased risk of developing SHCs during the subacute and chronic stage of tSCI in comparison with patients with motor-incomplete tSCI. Future studies should examine whether systematic monitoring during rehabilitation and the subacute and chronic phase in patients with motor-complete tSCI could lead to early detection and potential prevention of SHCs in this population

Healthy living the the Amsterdam region:Housing market, environmental quality, health and inequality in the metropolitan region

De centrale vraag was in hoeverre veranderde planning in de Amsterdamse regionale woningmarkt bijdraagt aan verschillen in de mate van blootstelling aan omgevingseffecten voor kopers en huurders, en in hoeverre omgevingskwaliteit en vervuiling te koppelen is aan gezondheidsuitkomsten.Het onderzoek bracht hierom unieke, grootschalige kwantitatieve datasets over woonomgeving, individuele bewoners en medische gesteldheid bij elkaar. Hierdoor kon de blootstelling aan luchtvervuiling, geluidoverlast, groenvoorzieningen en hittestress vergeleken worden, en konden de effecten van blootstelling op psychische en lichamelijke gezondheid geschat worden. Het onderzoek laat verschillen zien zijn tussen kopers en huurders in blootstelling. In de meest recente nieuwbouw is dit verschil met name groter voor particuliere huurders. Dit lijkt een gevolg van recente verstedelijking langs infrastructuur en in bevolkte gebieden (verdichting in de stad). Ondanks aanzienlijke blootstellings- en gezondheidsverschillen tussen huurders en kopers, is het verband tussen verschillen in blootstelling en gezondheidsuitkomsten echter zwak, en behoeft verder onderzoek.De uitkomsten dragen bij aan academische debatten over milieurechtvaardigheid, ruimtelijke gezondheid, en het cumulatieve karakter van ongelijkheden. Daarnaast biedt het inzicht in de opeenstapeling van verschillende dimensies van ongelijkheid en kunnen de bevindingen bijdragen aan de ontwikkeling van interventies en beleid voor een duurzame, gezondere, en rechtvaardigere ruimtelijke ordening, buurtontwikkeling en woningmarkt. Om beleid en interventies te helpen zijn samen met maatschappelijke partners vijf beleidsdilemma’s opgesteld.Het twee jaar durende onderzoek is uitgevoerd door een interdisciplinair team van geografen, planologen en medisch onderzoekers van Amsterdam Institute for Social Science Research (AISSR) en van Amsterdam UMC, onder leiding van dr. Wouter van Gent (Urban Geographies, UvA). Maatschappelijke partners zijn GGD Amsterdam, Amsterdamse Federatie Woningcorporaties, Stichting de Gezonde Stad, en de Gemeente Amsterdam. Het project is gefinancierd door Kenniscentrum Ongelijkheid