Morphology, Development, and Sediment Dynamics of Elongating Linear Dunes on Mars

Linear dunes occur on planetary surfaces, including Earth, Mars, and Titan, yet their dynamics are poorly understood. Recent studies of terrestrial linear dunes suggest they migrate by elongation only in supply limited environments. Here, we investigate elongating linear dunes in the Hellespontus Montes region of Mars which are morphologically similar to terrestrial systems. Multi‐temporal, high‐resolution orbital images show these linear dunes migrate by elongation only and that the fixed sediment source of the dunes probably restricts any lateral migration. Some linear dunes maintain their along length volume and elongate at rates comparable to adjacent barchans, whereas those which decrease in volume show no elongation, suggesting they are near steady state, matching morphometric predictions. Limited sediment supply may restrict Martian linear dunes to several kilometers, significantly shorter than many terrestrial linear dunes. Our results demonstrate the close similarities in dune dynamics across the two planetary surfaces

The Stratigraphy of Central and Western Butte and the Greenheugh Pediment Contact

The Greenheugh pediment at the base of Aeolis Mons (Mt. Sharp), which may truncate units in the Murray formation and is capped by a thin sandstone unit, appears to represent a major shift in climate history within Gale crater. The pediment appears to be an erosional remnant of potentially a much more extensive feature. Curiositys traverse through the southern extent of Glen Torridon (south of Vera Rubin ridge) has brought the rover in contact with several new stratigraphic units that lie beneath the pediment. These strata were visited at two outcrop-forming buttes (Central and Western butte- both remnants of the retreating pediment) south of an orbitally defined boundary marking the transition from the Fractured Clay-bearing Unit (fCU) and the fractured Intermediate Unit (fIU). Here we present preliminary interpretations of the stratigraphy within Central and Western buttes and propose the Western butte cap rocks do not match the pediment capping unit

A Lacustrine Paleoenvironment Recorded at Vera RubinRidge, Gale Crater: Overview of the Sedimentology and Stratigraphy Observed by the Mars ScienceLaboratory Curiosity Rover

For ~500 Martian solar days (sols), the Mars Science Laboratory team explored Vera Rubin ridge (VRR), a topographic feature on the northwest slope of Aeolis Mons. Here we review the sedimentary facies and stratigraphy observed during sols 1,800–2,300, covering more than 100 m of stratigraphic thickness. Curiosity's traverse includes two transects across the ridge, which enables investigation of lateral variability over a distance of ~300 m. Three informally named stratigraphic members of the Murray formation are described: Blunts Point, Pettegrove Point, and Jura, with the latter two exposed on VRR. The Blunts Point member, exposed just below the ridge, is characterized by a recessive, fine‐grained facies that exhibits extensive planar lamination and is crosscut by abundant curvi‐planar veins. The Pettegrove Point member is more resistant, fine‐grained, thinly planar laminated, and contains a higher abundance of diagenetic concretions. Conformable above the Pettegrove Point member is the Jura member, which is also fine‐grained and parallel stratified, but is marked by a distinct step in topography, which coincides with localized meter‐scale inclined strata, a thinly and thickly laminated facies, and occasional crystal molds. All members record low‐energy lacustrine deposition, consistent with prior observations of the Murray formation. Uncommon outcrops of low‐angle stratification suggest possible subaqueous currents, and steeply inclined beds may be the result of slumping. Collectively, the rocks exposed at VRR provide additional evidence for a long‐lived lacustrine environment (in excess of 106 years via comparison to terrestrial records of sedimentation), which extends our understanding of the duration of habitable conditions in Gale crater

A cross-sectional survey of mental health clinicians’ knowledge, attitudes, and practice relating to tobacco dependence among young people with mental disorders

BACKGROUND: Mental health services in England are smoke-free by law and expected to provide comprehensive support to patients who smoke. Although clinicians’ knowledge in this area is reported to be limited, research exploring the issue in Child and Adolescent Mental Health Services (CAMHS) is lacking. This study aimed to investigate the knowledge, attitudes, and practice of clinicians working within specialist and highly specialist Child and Adolescent Mental Health Services (CAMHS) relating to tobacco dependence, its treatment and its relation to mental disorder. METHODS: A cross-sectional survey of clinicians working across all CAMHS teams of a large UK National Health Service mental health Trust. RESULTS: Sixty clinicians (50% response rate) completed the survey. Less than half (48.3%) believed that addressing smoking was part of their responsibility, and half (50%) asserted confidence in supporting patients in a cessation attempt. Misconceptions relating to smoking were present across all staff groups: e.g. only 40% of respondents were aware of potential interactions between smoking and antipsychotic medications, although psychiatrists were more knowledgeable than non-medical clinicians (91.6% vs 27.1%; OR 3.4, p < .001). Self-reported attendance at smoking-related training was significantly associated with more proactive clinical practice. CONCLUSIONS: There is a need to improve clinicians’ knowledge, capacity and confidence in effectively identifying, motivating, supporting and treating young smokers in the context of treatment for mental disorders. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12913-014-0618-x) contains supplementary material, which is available to authorized users

Extraformational sediment recycling on Mars

Extraformational sediment recycling (old sedimentary rock to new sedimentary rock) is a fundamental aspect of Earth's geological record; tectonism exposes sedimentary rock, whereupon it is weathered and eroded to form new sediment that later becomes lithified. On Mars, tectonism has been minor, but two decades of orbiter instrument-based studies show that some sedimentary rocks previously buried to depths of kilometers have been exposed, by erosion, at the surface. Four locations in Gale crater, explored using the National Aeronautics and Space Administration's Curiosity rover, exhibit sedimentary lithoclasts in sedimentary rock: At Marias Pass, they are mudstone fragments in sandstone derived from strata below an erosional unconformity; at Bimbe, they are pebble-sized sandstone and, possibly, laminated, intraclast-bearing, chemical (calcium sulfate) sediment fragments in conglomerates; at Cooperstown, they are pebble-sized fragments of sandstone within coarse sandstone; at Dingo Gap, they are cobble-sized, stratified sandstone fragments in conglomerate derived from an immediately underlying sandstone. Mars orbiter images show lithified sediment fans at the termini of canyons that incise sedimentary rock in Gale crater; these, too, consist of recycled, extraformational sediment. The recycled sediments in Gale crater are compositionally immature, indicating the dominance of physical weathering processes during the second known cycle. The observations at Marias Pass indicate that sediment eroded and removed from craters such as Gale crater during the Martian Hesperian Period could have been recycled to form new rock elsewhere. Our results permit prediction that lithified deltaic sediments at the Perseverance (landing in 2021) and Rosalind Franklin (landing in 2023) rover field sites could contain extraformational recycled sediment.With funding from the Spanish government through the "María de Maeztu Unit of Excellence" accreditation (MDM-2017-0737

Critical Dimensions in Architectural Photography: Contributions to Architectural Knowledge

This paper illustrates and explores three critical dimensions of photography in architecture, each of which informs the production of images, texts, and other artifacts which establish what might be called a building’s media footprint. The paper’s broad goal is to question the extent to which these critical dimensions are relevant to architectural decision-making processes. Acknowledging that such dimensions as the ones examined here rarely predict an architect’s specific design decisions in a transparent manner, the paper discusses not only the decisions made by architects during the process of designing buildings, but the decisions made by critics, visitors, and members of the general public as they engage in activities such as visiting buildings, writing about them and, particularly, photographing them. First, the text discusses the potential of buildings to operate as mechanisms for producing images, in the sense originated by Beatriz Colomina. The question is developed through the analysis of the space of photography – mapping of points of view, directions of view, and fields of view of defined photographic collections. Secondly, it considers photography’s complicity in the canonization of buildings, and specifically, the extent to which photography is responsible for distinguishing between major and minor architectural works. Finally, the essay examines the erosion over time of photography’s historical power to frame when confronted with contemporary technologies of virtual reality and photo realistically rendered digital models. Each of these critical dimensions, or concepts, develops a specific aspect of how photographic information about buildings is organized, structured, and disseminated, and is thus only part of the larger project of architectural epistemology, which inquires into this wider field. This will be done through an examination of the Mies van der Rohe-designed Commons Building at ITT in Chicago and the evolution of its relationship with architectural photography and photographic representation – both on its own terms and through the prism of the Rem Koolhaas-designed McCormick Tribune Student Center, which adds to and incorporates the Commons Building. Until the end of the twentieth century, the Commons Building on the campus of the Illinois Institute of Technology was generally considered one of Mies van der Rohe’s lesser works. Reportedly neglected by its own architect during the design process, and frequently marginalized in academic discussions of the campus, when mentioned at all the building was often cited as an unrefined prototype of Crown Hall. This discourse took a new direction when in 1998, Rem Koolhaas/OMA won a design competition for a student center on the IIT campus: uniquely among the competition entries, Koolhaas’s design incorporated the Commons Building within a new context – what ultimately became the McCormick Tribune Campus Center (MTCC). When critics concluded that the incorporation of the Commons Building into the larger whole could compromise its integrity as an exemplar of Mies’s work, the building became the object of renewed interest and controversy. The two projects considered here show a clear evolution in architecture’s relationship with the photographic image. Specifically, the history of the Commons Building can be traced through photographs: during and shortly following its construction, the building was photographed as part of Mies’s own attention to publicity; it was documented as part of historical analyses; and over time it was visited and photographed by casual and amateur photographers. Following the competition results, photographs of the Commons Building were strategically deployed by both proponents and critics of Koolhaas’s design. Contemporary photographs of the building appear in architectural and campus guidebooks and on websites such as Flickr.com. Examining the ways in which photographs of the Commons Building appear in these various contexts allows discussion of the critical dimensions identified above and permits us to trace the evolution of the mutually reinforcing relationship between architecture and photography

Revealing Repton: bringing landscape to life at Sheringham Park

The year 2012 marked 200 years since Humphry Repton (1752–1818) produced his design for Sheringham Park in north Norfolk, bound as one of his Red Books. On paper, Repton is England’s best-known and most influential landscape gardener. On the ground, his work is much harder to identify, focused as it was on light touches that equated more to landscape makeover than the landscape making of his predecessor Lancelot “Capability” Brown. This paper documents and evaluates a project that celebrated this bicentenary through a temporary exhibition within the visitor centre of Sheringham Park, whilst also making reference to the commemoration of his work in other places and on paper. In attempting to reveal Repton at Sheringham, we explore the context of the 1812 commission and the longer landscape history of the site, as well as the different methods of representing Repton on site that are open to site owners and managers