An empirical investigation of the Pathways Model of problem gambling through the conjoint use of self-reports and behavioural tasks

Background and aims Blaszczynski and Nower (2002) conceptualized their Pathways Model by postulating the existence of three subtypes of problem gamblers who share common characteristics, but also present specific ones. Methods This study investigated how the psychological mechanisms postulated in the Pathways Model predict clinical status in a sample that combined treatment-seeking gamblers (n = 59) and non-problematic community gamblers (n = 107). To test the Pathways Model, we computed a hierarchic logistic regression in which variables associated with each postulated pathway were entered sequentially to predict the status of the treatment-seeking gambler. Self-report questionnaires measured gambling-related cognitions, alexithymia, emotional reactivity, emotion regulation strategies and impulsivity. Behavioural tasks measured gambling persistence (slot machine task), decision-making under uncertainty (Iowa Gambling Task) and decision-making under risk (Game of Dice Task). Results We showed that specific factors theorized as underlying mechanisms for each pathway predicted the status of clinical gambler. For each pathway, significant predictors included gambling-related cognitive distortions and behaviourally measured gambling persistence (behaviourally conditioned pathway), emotional reactivity and emotion regulation strategies (emotionally vulnerable pathway), and lack of premeditation impulsivity facet (impulsivist-antisocial pathway). Discussion and conclusions Our study adds to the body of literature confirming the validity of the Pathways Model and hold important implications in terms of assessment and treatment of problem gambling. In particular, a standardized assessment based on the Pathways Model should promote individualized treatment strategies to allow clinicians to take into account the high heterogeneity that characterizes gambling disorder

Synthesis of the distribution of subsidence of the lower Ganges-Brahmaputra Delta, Bangladesh

Deltas, the low-lying land at river mouths, are sensitive to the delicate balance between sea level rise, land subsidence and sedimentation. Bangladesh and the Ganges-Brahmaputra Delta (GBD) have been highlighted as a region at risk from sea-level rise, but reliable estimates of land subsidence have been limited. While early studies suggested high rates of relative sea-level rise, recent papers estimate more modest rates. Our objective is to better quantify the magnitude, spatial variability, and depth variation of sediment compaction and land subsidence in the lower GBD to better evaluate the processes controlling them and the pattern of relative sea level rise in this vulnerable region. We combine subsidence and compaction estimates from hand-drilled tube wells and historic sites (1–5 mm/y), GNSS and river gauges (4–8 mm/y) and RSET-MH and borehole vertical strainmeters (9–10 mm/y) in SW Bangladesh. The differences between the different types of measurements reflect the different timescales, spatial distribution and depth sensitivity of the different observations. Rates are lower for times >300y providing data on the timescale of compaction. We also observe differences related to the degree to which different devices measure shallow and deep subsidence. Higher values reflect a greater component of subsidence from young shallow deposits from soil compaction and organic matter degradation. Thus, we observe different rates for different environments and physical settings. These differences indicate that in planning adaptation for rising sea level, hard construction with a solid foundation may experience different subsidence rates than open fields or reclaimed land with recent natural or anthropogenic sedimentation. Significance statement: Land subsidence increases the impact of sea level rise. We combine six different types of measurements that examine land subsidence in coastal Bangladesh. The results show that causes of subsidence, including compaction of the sediments varies both spatially and with depth, and that compaction and organic matter degradation from young shallow deposits is a significant contribution to subsidence. This suggests that hard construction with a solid foundation, such as buildings and embankments, may experience a lower subsidence rates than open fields or reclaimed land with recent natural or anthropogenic sedimentation

Multidisciplinary investigation on cold seeps with vigorous gas emissions in the Sea of Marmara (MarsiteCruise): Strategy for site detection and sampling and first scientific outcome

MarsiteCruise was undertaken in October/November 2014 in the Sea of Marmara to gain detailed insight into the fate of fluids migrating within the sedimentary column and partially released into the water column. The overall objective of the project was to achieve a more global understanding of cold-seep dynamics in the context of a major active strike-slip fault. Five remotely operated vehicle (ROV) dives were performed at selected areas along the North Anatolian Fault and inherited faults. To efficiently detect, select and sample the gas seeps, we applied an original procedure. It combines sequentially (1) the acquisition of ship-borne multibeam acoustic data from the water column prior to each dive to detect gas emission sites and to design the tracks of the ROV dives, (2) in situ and real-time Raman spectroscopy analysis of the gas stream, and (3) onboard determination of molecular and isotopic compositions of the collected gas bubbles. The in situ Raman spectroscopy was used as a decision-making tool to evaluate the need for continuing with the sampling of gases from the discovered seep, or to move to another one. Push cores were gathered to study buried carbonates and pore waters at the surficial sediment, while CTD-Rosette allowed collecting samples to measure dissolved-methane concentration within the water column followed by a comparison with measurements from samples collected with the submersible Nautile during the Marnaut cruise in 2007. Overall, the visited sites were characterized by a wide diversity of seeps. CO2- and oil-rich seeps were found at the westernmost part of the sea in the Tekirdag Basin, while amphipods, anemones and coral populated the sites visited at the easternmost part in the Cinarcik Basin. Methane-derived authigenic carbonates and bacterial mats were widespread on the seafloor at all sites with variable size and distributions. The measured methane concentrations in the water column were up to 377 μmol, and the dissolved pore-water profiles indicated the occurrence of sulfate depleting processes accompanied with carbonate precipitation. The pore-water profiles display evidence of biogeochemical transformations leading to the fast depletion of seawater sulfate within the first 25-cm depth of the sediment. These results show that the North Anatolian Fault and inherited faults are important migration paths for fluids for which a significant part is discharged into the water column, contributing to the increase of methane concentration at the bottom seawater and favoring the development of specific ecosystems

The submerged section of the North Anatolian Fault within the Sea of Marmara : evolution of the fault network and fluid migration

Cette thèse porte sur la déformation et les migrations de fluides associées à la Faille Nord Anatolienne en Mer de Marmara (Turquie).Nous étudions tout d'abord l'évolution de la géométrie et du taux de glissement du système de faille, par deux approches indépendantes: - modélisation thermique de l'histoire d'un bassin, - définition d'un marqueur temporel de type Dépôt de Transport en Masse, daté par interprétation stratigraphique. Nous montrons que: -(1) le système de failles actuel, défini comme une faille principale accommodant la majorité de la déformation inter-plaque, n'a pas significativement évolué depuis 330.000 ± 100.000 ans dans la partie Ouest de la mer; -(2) le système de faille s'est progressivement réorganisé depuis 2.5-1.5 Ma.Dans un deuxième temps, nous étudions les processus d'initiation des Transports en Masse. Nous montrons que: -(1) même si les Transports en Masse sont contrôlés par des processus tectoniques (principalement les séismes et l'extension crustale), leur fréquence et leur taille sont conditionnées par les oscillations glacio-eustatiques; -(2) des Dépôts en Masse ont une périodicité corrélée aux transitions marins/lacustres. Cette cyclicité peut être expliquée par la diffusion d'eau saumâtre, dans les argiles marines entraînant leur gonflement et déstabilisant les sédiments. Dans une troisième partie, nous étudions la diversité des contextes des sites d'émissions de fluides en fonds de mer. Nous montrons que l'occurrence des sites d'émission de fluides est en partie liée au flux ascendant de gaz le long de couches perméables des bassins vers leurs bords, et le long des fractures du socle vers les bords des bassins et les anticlinaux.This study addresses the issue on the deformation and the fluid migration, associated to the North Anatolian Fault within the Sea of Marmara (Turkey).First, we aim to constrain the evolution of the fault network and the slip rate through time, by two independent approaches: - historical thermal modeling of a basin of the Sea of Marmara; - definition of a Mass Transport Deposit as a fault lateral slip marker, and dated by stratigraphic interpretation. We show that: - (1) the present day fault system, formed by a main fault which accommodated the main part of the inter-plate deformation does not significantly evolved since 330.000 ± 100.000 years - (2) a progressive reorganization of the fault network occurred since the last 2.5-1.5 Ma.Secondly, we discuss the triggers of Mass Transport Processes. We show that: - (1) despite submarine mass movements are related to tectonic activity (mainly earthquakes and crustal stretching), their frequency and their size are also modulated by glacio-eustatic changes; -(2) remarkable Mass Transport Deposits display some cyclicity in stratigraphic sequences which are apparently correlated to transitions between salty marine and lacustrine environments. This cyclicity is perhaps explained by marine clay activity (swelling) under low brackish-fresh water conditions, which can trigger sediment destabilization.Third, we investigate the diversity of active fluid seepages contexts. We propose that the widespread occurrence of fluid expulsion sites can be explained by up-dip gas migration by buoyancy along permeable strata toward their edges, and along fractures within the basement toward both the edges of the basins and topographic highs

Contribution of campaign GNSS toward parsing subsidence rates by time and depth in coastal Bangladesh

International audienceCoastal regions are vulnerable to rising seas, increasing storm magnitude, and decimation of ecologically fragile areas. Deltas are particularly sensitive to the balance between sea level rise, land subsidence and sedimentation that determine relative elevation. Bangladesh has been highlighted as being at risk from sea level rise, but reliable estimates of land subsidence are limited. Subsidence rates vary spatially, and with depth and time. However, integrating measurements from different methods can approach a more complete understanding of factors controlling spatially and temporally varying rates. To augment our compilation of rates from stratigraphic wells, historic buildings and structures, vertical strainmeters, RSET-MH, and continuous GNSS sites, we resurveyed geodetic monuments in coastal Bangladesh. We resurveyed 48 sites ~18 years after the monuments were installed. Approximately ½ the sites had high rates that we strongly suspected to result from unstable monuments, confirmed by a later resurvey of 4 sites. Remaining sites show subsidence rates of 13-15mm/y, tapering to 0-2mm/y in the northwestern part of the study area. Sites with rates <2 mm/y overlie thin (≤35m), sandy Holocene deposits. Remaining sites overlie thick (70 to >90m) muddy deposits within the incised valleys of the Ganges, Brahmaputra and Meghna Rivers. Together with earlier measurements, we parse the different rates and mechanisms of subsidence. We estimate 2-3mm/y correspond to deep processes, such as isostasy. 1-5mm/y is estimated to result from compaction of Holocene strata, with thicker and muddier strata undergoing greater compaction. Finally, 5-7 mm/y result from shallow, edaphic effects such as tree roots, burrows, organic matter decomposition, and shallow (≤10m) sediment consolidation on short timescales (10$^0$ -10$^2$ y) in the upper few meters. Subsidence rates in areas of active sedimentation, such as rice fields and mangrove forests, are greater than at buildings and structures without active sedimentation. Subsidence on timescales >300y, which does not include edaphic effects, are up to ~5mm/y. We note shallow subsidence can be offset by active deltaic sedimentation, and do not necessarily indicate elevation loss. Collectively, the integration of these approaches allows us to better quantify the varied contributions to land subsidence from edaphic effects, Holocene sediment compaction, lithology, and time

Propagation of a strike slip plate boundary within an extensional environment: the westward propagation of the North Anatolian Fault

The Sea of Marmara marks a key point in the propagation of the North Anatolian Fault (NAF) toward the northern extremity of the Aegean subduction during the last 12-11 Myr. There is no indication that a localized plate boundary existed to the west of it, north of the Aegean portion of the Anatolia plate, before 2 Ma. Prior to 2 Ma, the shear produced by the motion of Anatolia-Aegea with respect to Eurasia was distributed over the whole width of the Aegean-West Anatolian western portion. This was most probably related to the presence there of a N/S component of extension produced by the southward migration of the Aegean-West Anatolian subduction. Fast subduction of the oceanic Ionian lithosphere had been initiated 15 Ma ago, a few million years before the Anatolia westward motion began 11 Ma ago. These two processes are obviously tightly linked. We document the establishment of the Aegea-Anatolia/Eurasia plate boundary in Plio-Pleistocene time in this geodynamic context. We show that the beginning of the formation of a localized plate boundary occurred between 4.5 and 3.5 Ma ago at the location of the present Sea of Marmara by the initiation of a shear zone comparable to the Gulf of Corinth one in Central Greece. Thus the first part of the formation of the Sea of Marmara was purely extensional. We discuss the transition from the initial extensional basins to the present strike-slip system, that today cuts across the whole Sea of Marmara and that is called Main Marmara Fault (MMF). We show that the beginning of its development is not earlier than 2.5 Ma ago. Shortly after, the plate boundary migrated west of the Sea of Marmara along the northern border of Aegea from the North Aegean Trough, to the Gulf of Corinth area and to the Kefalonia fault. There, it finally linked with the northern tip of the Aegean subduction zone, completing the system of plate boundaries delimiting the Anatolia-Aegea plate. We have related the remarkable change in the distribution of shear over the whole Aegea from Miocene to Pliocene to the formation of a relatively undeforming block in Pliocene that forced the shear to be distributed over a narrow plate boundary to the north of it. We attribute the formation of this relatively undeforming Aegean block to the northeastward progression of the cold oceanic Ionian slab. We propose that the slab cuts the overlying lithosphere from asthenospheric sources and induces a shortening environment over it.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Correction to: Gas occurrence and shallow conduit systems in the Western Sea of Marmara: a review and new acoustic evidence

International audienc