Female newcomers’ adjustment to life in Toronto,Canada: sources of mental stress and their implications for delivering primary mental health care

Stress disorders and other mental ill health may be brought on by the disruption caused by resettlement. We examine female newcomers’ experiences of adjusting to a new place, metropolitan Toronto, Canada and a new health care system. We consider sources of mental stress experienced during adjustment. We frame this adjustment as a process that happens over place and through time. Thematic findings of interviews (n = 35) with female newcomers from five cultural-linguistic groups are reported. Sources of stress in adjusting to life in Toronto include: navigating a new place, personal safety concerns, adapting to a new lifestyle, and finding employment. Sources of stress in adjusting to a new health care system include: learning how to access care, not having access to specialists, and adapting to a new culture of care. We conclude by considering the implications of what newcomers report for the delivery of primary mental health care (i.e. ‘first contact’ care).     

Autogenic incision‐backfilling cycles and lobe formation during the growth of alluvial fans with supercritical distributaries

Autogenic cycles of channelization, terminal deposit formation, channel backfilling and channel abandonment have been observed in the formation of fans and deltas. In subcritical flow, these terminal deposits are characterized as mouth bars that lead to flow bifurcation, backwater and eventual channel backfilling. Similar, although less well characterized, cycles also take place on supercritical subaerial and submarine fans. This study investigates the hydraulics and morphodynamics of autogenic incision and backfilling cycles associated with supercritical distributive channel flow in alluvial fans. The research questions of the study are: (i) how are supercritical autogenic cycles on alluvial fans different from the subcritical cycles; (ii) what are the hydraulic and sediment transport characteristics at the various stages of autogenic feedback cycles; and (iii) what role do the cycles play in the overall fan evolution? These questions are investigated in the laboratory, and emphasis is placed on measuring the hydraulic and topographic evolution of the systems during the cycles. The cycles arise quasi‐periodically under constant water and sediment discharge. Periods of sheet‐like flow are competent to move sediment () but not competent enough to carry the full imposed load. The net result is preferential deposition near the inlet, resulting in fan steepening and an increase in flow competency with time. At a sediment supply to capacity ratio of , the sheet‐like flow is unstable to small erosional events near the inlet, resulting in the collapse of the distributed flow to a strong channelized state. During channelization, a graded () supercritical (Fr > 1) channel develops and transports eroded and fed sediment up to and through the fan front – extending the fan, initiating a lobe shaped deposit and reducing the local slope. The slopes defined by a sheet‐like flow with and channelized flow with set the maximum and minimum slopes on the fan, respectively. Once formed, graded channels act as bypass conduits linking the inlet with the terminal deposit. On average, deposits are up to six channel depths in thickness and have volumes approximately five times that of the excavated channel. The main distinctive characteristics of the supercritical cycles relate to how the flow interacts with the terminal deposit. At the channel to deposit transition, the flow undergoes a weak hydraulic jump, resulting in rapid sedimentation, dechannelization and lateral expansion of the flow, and deposition of any remaining sediment on top of the channel fill and floodplain. This process often caps the channel as the deposit propagates up channel erasing memory of the excavated channel.     

Characterization of Persistent Volatile Contaminant Sources in the Vadose Zone

Effective long‐term operation of soil vapor extraction (SVE) systems for cleanup of vadose‐zone sources requires consideration of the likelihood that remediation activities over time will alter the subsurface distribution and configuration of contaminants. A method is demonstrated for locating and characterizing the distribution and nature of persistent volatile organic contaminant (VOC) sources in the vadose zone. The method consists of three components: analysis of existing site and SVE‐operations data, vapor‐phase cyclic contaminant mass‐discharge testing, and short‐term vapor‐phase contaminant mass‐discharge tests conducted in series at multiple locations. Results obtained from the method were used to characterize overall source zone mass‐transfer limitations, source‐strength reductions, potential changes in source‐zone architecture, and the spatial variability and extent of the persistent source(s) for the Department of Energy's Hanford site. The results confirmed a heterogeneous distribution of contaminant mass discharge throughout the vadose zone. Analyses of the mass‐discharge profiles indicate that the remaining contaminant source is coincident with a lower‐permeability unit at the site. Such measurements of source strength and size as obtained herein are needed to determine the impacts of vadose‐zone sources on groundwater contamination and vapor intrusion, and can support evaluation and optimization of the performance of SVE operations.     

Mesozoic to Cenozoic tectono‐metamorphic history of the South Pamir–Hindu Kush (Chitral,NW Pakistan): Insights from phase equilibria modelling,and garnet–monazite petrochronology

The Karakoram–Hindu Kush–Pamir and adjacent Tibetan plateau belt comprise a series of Gondwana‐derived crustal fragments that successively accreted to the Eurasian margin in the Mesozoic as the result of the progressive Tethys ocean closure. These domains provide unique insights into the thermal and structural history of the Mesozoic to Cenozoic Eurasian plate margin, which are critical to inform the initial boundary conditions (e.g. crustal thickness, structure and thermo‐mechanical properties) for the subsequent development of the large and hot Tibetan–Himalaya orogen, and the associated crustal deformation processes. Using a combination of microstructural analyses, thermobarometry modelling and U–Th–Pb monazite and Lu–Hf garnet geochronology, the study reappraises the metamorphic history of exposed mid‐crustal metapelites in the Chitral region of the South Pamir–Hindu Kush (NW Pakistan). This study also demonstrates that trace elements in monazite (especially Y and Dy), combined with thermodynamical modelling and Lu–Hf garnet dating, provides a powerful integrated toolbox for constraining long‐lived and polyphased tectono‐metamorphic histories in all their spatial and temporal complexity. Rocks from the Chitral region were progressively deformed and metamorphosed at sub‐ and supra‐solidus conditions through at least four distinct episodes from the Mesozoic to the Cenozoic. Rocks were first metamorphosed at ~400–500°C and ~0.3 GPa in the Late Triassic–Early Jurassic (210–185 Ma), likely in response to the accretion of the Karakoram during the Cimmerian orogeny. Pressure and temperature subsequently increased by ~0.3 GPa and 100°C in the Early‐ to Mid Cretaceous (140–80 Ma), coinciding with the intrusion of calcalkaline granitic plutons across the Karakoram and Pamir regions. This event is interpreted as the record of crustal thickening and the development of a proto‐plateau within the Eurasian margin due to a long‐lived episode of slab flattening in an Andean‐type margin. Peak metamorphism was reached in the Late Eocene–Early Oligocene (40–30 Ma) at conditions of 580–600°C and ~0.6 GPa and 700–750°C and 0.7–0.8 GPa for the investigated staurolite schists and sillimanite migmatites respectively. This crustal heating up to moderate anatexis likely resulted in the underthrusting of the Indian plate after a NeoTethyan slab‐break off or to the Tethyan Himalaya–Lhasa microcontinent collision and subsequent oceanic slab flattening. Near‐isothermal decompression/exhumation followed in the Late Oligocene (28–23 Ma) as marked by a pressure decrease in excess of ~0.1 GPa. This event was coeval with the intrusion of the 24 Ma Garam Chasma leucogranite. This rapid exhumation is interpreted to be related to the reactivation of the South Pamir–Karakoram suture zone during the ongoing collision with India. The findings of this study confirm that significant crustal shortening and thickening of the south Eurasian margin occurred during the Mesozoic in an accretionary‐type tectonic setting through successive episodes of terrane accretions and probably slab flattening, transiently increasing the coupling at the plate interface. Moreover, they indicate that the south Eurasian margin was already hot and thickened prior to Cenozoic collision with India, which has important implications for orogen‐scale strain‐accommodation mechanisms.     

Quantifying large‐scale historical formation of accommodation in the Mississippi Delta

Large volumes of new accommodation have formed within the Mississippi Delta plain since the mid‐1950s in association with rapid conversion of coastal wetlands to open water. The three‐dimensional aspects and processes responsible for accommodation formation were quantified by comparing surface elevations, water depths, and vertical displacements of stratigraphic contacts that were correlated between short sediment cores. Integration of data from remotely sensed images, sediment cores, and water‐depth surveys at 10 geologically diverse areas in the delta plain provided a basis for estimating the total volume of accommodation formed by interior‐wetland subsidence and subsequent erosion. Results indicate that at most of the study areas subsidence was a greater contributor than erosion to the formation of accommodation associated with wetland loss. Tens of millions of cubic meters of accommodation formed rapidly at each of the large open‐water bodies that were formerly continuous interior delta‐plain marsh. Together the individual study areas account for more than 440 × 10⁶ × m³ of new accommodation that formed as holes in the Mississippi River delta‐plain fabric between 1956 and 2004. This large volume provides an estimate of the new sediment that would be needed just at the study areas to restore the delta‐plain wetlands to their pre‐1956 areal extent and elevations. Published 2010. This article is a US Government work and is in the public domain in the USA.     

A survey of ultraviolet-bright sources behind the halo of M31

We have performed a wide-area ultraviolet (UV) imaging survey using the GALaxy Evolution eXplorer to search for bright, point-like UV sources behind M31's extended halo. Our survey consisted of 46 pointings covering an effective area of ≈50 deg², in both the far-UV and near-UV channels. We combined these data with optical R -band observations acquired with the WIYN Mosaic-1 imager on the Kitt Peak National Observatory 0.9-m WIYN telescope. An analysis of the brightness and colours of sources matched between our photometric catalogues yielded ≈100 UV-bright quasar candidates. We have obtained discovery spectra for 76 of these targets with the Kast spectrometer on the Lick 3-m telescope and confirmed 30 active galactic nuclei and quasars, 29 galaxies at   z > 0.02  including several early-type systems, 16 Galactic stars (hot main-sequence stars) and one featureless source previously identified as a BL Lac object. Future UV spectroscopy of the brightest targets with the Cosmic Origins Spectrograph on the Hubble Space Telescope will enable a systematic search for diffuse gas in the extended halo of M31.     

Mineralogy and crystallization history of a highly differentiated REE-enriched hypabyssal rhyolite: Round Top laccolith,Trans-Pecos,Texas

Mineralogy and Petrology - The Round Top hypabyssal rhyolite laccolith is a highly evolved magmatic system, enriched in incompatible elements including REE [Rare Earth Element(s)], U, Be, and F....     

Geology of the Elephanta Island fault zone,western Indian rifted margin,and its significance for understanding the Panvel flexure

The Panvel flexure is a 150-km long tectonic structure, comprising prominently seaward-dipping Deccan flood basalts, on the western Indian rifted margin. Given the active tectonic faulting beneath the Panvel flexure zone inferred from microseismicity, better structural understanding of the region is needed. The geology of Elephanta Island in the Mumbai harbour, famous for the ca. mid-6th century A.D. Hindu rock-cut caves in Deccan basalt (a UNESCO World Heritage site) is poorly known. We describe a previously unreported but well-exposed fault zone on Elephanta Island, consisting of two large faults dipping steeply east–southeast and producing easterly downthrows. Well-developed slickensides and structural measurements indicate oblique slip on both faults. The Elephanta Island fault zone may be the northern extension of the Alibag–Uran fault zone previously described. This and two other known regional faults (Nhava–Sheva and Belpada faults) indicate a progressively eastward step-faulted structure of the Panvel flexure, with the important result that the individual movements were not simply downdip but also oblique-slip and locally even rotational (as at Uran). An interesting problem is the normal faulting, block tectonics and rifting of this region of the crust for which seismological data indicate a normal thickness (up to 41.3 km). A model of asymmetric rifting by simple shear may explain this observation and the consistently landward dips of the rifted margin faults.     

Timing of metamorphism and deformation in the Swat valley,northern Pakistan:Insight into garnet-monazite HREE partitioning

New metamorphic petrology and geochronology from the Loe Sar dome in the Swat region of northern Pakistan place refined constraints on the pressure, temperature and timing of metamorphism and deformation in that part of the Himalayan orogen. Thermodynamic modelling and monazite petrochronology indicate that metamorphism in the area followed a prograde evolution from ～525 ± 25 ℃and 6 士 0.5 kbar to ～610 ± 25 ℃ and 9 士 0.5 kbar, between ca. 39 Ma and 28 Ma. Partitioning of heavy rare earth elements between garnet rims and 30-28 Ma monazite are interpreted to indicate coeval crystallization at peak conditions. Microtextural relationships indicate that garnet rim growth post-dated the development of the main foliation in the area. The regional foliation is folded about large-scale N-S trending fold axes and overprinting E-W trending folds to form km-scale domal culminations. The textural relationships observed indicate that final dome development must be younger than the 30-28 Ma monazite that grew with garnet rims post-regional foliation development, but pre-doming-related deformation. This new timing constraint helps resolve discrepancy between previous interpretations,which have alternately suggested that N-S trending regional folds must be either pre-or post-early Oligocene. Finally, when combined with existing hornblende and white mica cooling ages, these new data indicate that the study area was exhumed rapidly following peak metamorphism.     

A nonlinear stability problem in the three dimensional restricted three body problem

The question of whether or not there is a transfer of energy between the in-plane motion and out-of-plane motion in the neighborhood ofL ₄ in the restricted problem of three bodies is investigated in this paper. The in-plane motion is assumed to be finite and the out-of-plane motion to be infinitesimal. The equation governing the out-of-plane motion becomes one with time varying coefficients. The stability of this equation is then investigated using Lie Series.Presented as a paper AAS No. 70-313, at the AAS/AIAA Astrodynamics Specialists Conference 1971 at Fort Lauderdale Fla., U.S.A.