bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mothers of young adults with intellectual disability: multiple roles, ethnicity and well‐being
Authors: Eisenhower A. , Blacher J. 
Published: November 2006

AbstractBackground  Two opposing perspectives – role strain and role enhancement – were considered as predictive of women’s psychological and physical health. The authors examined the relation between multiple role occupancy (parenting, employment, marriage) and well‐being (depression and health) among mothers of young adults with intellectual disability (ID).Methods  Participants were 226 mothers aged 35–70 years old caring for a young adult aged 16–26 years old with moderate to severe/profound ID. Mothers were of either Latino ethnicity (n = 117) or Anglo (n = 109). Mothers’ ethnicity and degree of acculturation and young adults’ adaptive behaviour and behaviour problems were examined as potential moderators.Results  Mothers who were employed, married, or both reported better well‐being than mothers who were both unemployed and unmarried, especially when their offspring had relatively higher adaptive functioning. This relationship between role occupancy and well‐being was fully mediated by socio‐economic status (SES) factors. Results did not suggest a role enhancement effect, but instead indicated a role shortage effect; unemployed, unmarried mothers experienced markedly poor well‐being, while all other mothers experienced comparable well‐being. Well‐being scores were higher for Anglo than for Latino mothers; this relationship was entirely accounted for by SES. In Latina mothers, the relation between role occupancy and well‐being was moderated by degree of acculturation.Conclusions  Findings suggest that multiple roles benefit mothers of young adults with ID primarily through their impact on socio‐economic resources. For more acculturated Latina mothers, occupying more roles predicted better well‐being even after controlling for SES. Latina mothers who were unemployed and unmarried had lower SES, and this group emerged as at particular risk. The latter group may benefit most from respite assistance and other interventions aimed at addressing their physical and mental health.
Child, parent and family factors as predictors of adjustment for siblings of children with a disability
Authors: Giallo R. , Gavidia‐Payne S. 
Published: November 2006

AbstractBackground  Siblings adjust to having a brother or sister with a disability in diverse ways. This study investigated a range of child, parent and family factors as predictors of sibling adjustment outcomes.Methods  Forty‐nine siblings (aged 7–16 years) and parents provided information about (1) sibling daily hassles and uplifts; (2) sibling coping; (3) parent stress; (4) parenting; and (5) family resilience. Multiple regression techniques were used.Results  It was found that parent and family factors were stronger predictors of sibling adjustment difficulties than siblings’ own experiences of stress and coping. Specifically, socio‐economic status, past attendance at a sibling support group, parent stress, family time and routines, family problem‐solving and communication, and family hardiness‐predicted sibling adjustment difficulties. Finally, siblings’ perceived intensity of daily uplifts significantly predicted sibling prosocial behaviour.Conclusions  The results revealed that the family level of risk and resilience factors were better predictors of sibling adjustment than siblings’ own experiences of stress and coping resources, highlighting the importance of familial and parental contributions to the sibling adjustment process. The implications of these results for the design of interventions and supports for siblings are discussed.
Personality, coping style and well‐being of parents rearing children with developmental disabilities
Authors: Glidden L. M. , Billings F. J. , Jobe B. M. 
Published: November 2006

AbstractBackground  Parents with children with developmental disabilities (DD) encounter a variety of stressors associated with rearing their children and must develop effective coping mechanisms in order to adapt successfully to these challenges. Previous research has failed to establish the role of parental individual differences in the reported use of different coping strategies. The current study explores parental personality and whether children with DD were adopted or born into the families and their influence on the coping strategies used by mothers and fathers.Methods  A total of 97 mother–father dyads rearing at least one child with DD were participants. They narrated stressful situations related to their child and completed the Ways of Coping Questionnaire twice. Data were also collected with regard to personality, depression and subjective well‐being (SWB).Results  Both adoptive and birth mothers and fathers used more problem‐focused than emotion‐focused strategies. Personality factors, Neuroticism especially, were predictive of coping strategy use. Higher levels of Positive Reappraisal were associated with higher levels of SWB, whereas higher levels of Escape‐Avoidance were associated with lower levels of SWB, but only for mothers. Results were consistent with a dispositional model of strategy use in that frequency of use was associated with personality characteristics, was consistent over time, and for different children in the same families. Future research should focus on the persistence of the associations between strategy use and well‐being and whether they hold true at different stages of the lifespan when coping contexts may change quite dramatically.
Facies, geometry and geological significance of Late Ordovician (early Caradocian) coral bioherms: Lourdes Formation, western Newfoundland
Authors: BATTEN HENDER KELLY L. , DIX GEORGE R. 
Published: November 2006

AbstractLate Ordovician coral bioherms in the Lourdes Formation of western Newfoundland exhibit a complex mixing of architectural elements, including framework, boundstone and suspension deposits. The bioherms occur within a narrow (16 m) stratigraphic interval, and a prominent unconformity truncates the interval of bioherm growth and tops of many of the bioherms. The buildups developed along a carbonate ramp. They occur isolated and in groups, individuals in groups are aligned in parallel orientation. The sizes of the bioherms range from small (50–100 cm) coral piles to columnar and dome‐shaped masses (1–15 m); however, topographic relief was never more than ≈1 m. Bioherm construction reflects: (i) stacking of the tabulate coral Labyrinthites chidlensis, and less common stromatoporoids; (ii) accumulation of microbial‐stromatoporoid boundstone and suspension deposits within shelter cavities between corals; and (iii) detrital bioherm‐flank skeletal grainstone beds. Trypanites borings are common in the tops of coral heads. The bioherms exhibit three growth‐development stages: (i) seafloor stabilization, wherein rare, abraded coral colonies lie scattered within pelmatozoan/skeletal grainstone lenses; (ii) colonization, wherein corals (L. chidlensis), rare stromatoporoids (Labechia sp.), and other biota (bryozoans) produced a bioherm overlying the basal sediment base; and (iii) diversification, which is marked by a more diverse range of fauna and flora as well as occurrence of shelter‐cavity deposits. The diversification stage usually makes up more than 70% of a bioherm structure, and, in some defines multiple periods of start‐up and shut‐down of bioherm growth. The latter is defined by bored omission surfaces and/or deposition of inter‐bioherm sediment. The Lourdes bioherms have a similar ecological structure, biotic diversity and depositional environment to patch reefs in the equivalent Carters Limestone in Tennessee. The mixture of coral stacking and boundstone as architectural elements identify an Early Palaeozoic transition of reef‐design development along shallow‐water platforms that began to displace the muddy (boundstone, bafflestone) carbonate buildups more typical of the Early and Middle Ordovician time.
Form, function and feedbacks in a tidally dominated ooid shoal, Bahamas
Authors: RANKEY EUGENE C. , RIEGL BERNHARD , STEFFEN KELLEY 
Published: November 2006

AbstractAlthough the general aspects of oolitic depositional systems are well documented, seascape‐scale (≈103–106 m2) patterns of oolitic shoals and the details of processes acting on them are not well understood or quantified. To begin to fill this basic gap in understanding, this paper describes the morphology and hydrodynamics of Lily Bank, a Modern tidally dominated Bahamian ooid shoal. In this study, integrating remote sensing imagery with quantitative, geo‐located bathymetrical, hydrological and granulometric data in a Geographic Information System documents geomorphic and sedimentological patterns and facilitates interpreting these patterns in the context of the processes operating in this system. The results of these analyses reveal that parabolic bars up to several kilometres in wavelength and several metres in height form a common morphologic motif, although there is considerable variation on that general theme. The seascape‐scale configuration of bars and superimposed sedimentary structures is closely linked to spatial patterns of tidal movements, and includes the presence of mutually evasive flood and ebb channels. Sedimentologically, bars are neither homogenous nor random bodies; instead, granulometric parameters such as sorting and percentage mud vary systematically, as shaped by hydro‐geomorphic controls. The best sorted, coarsest ooids are on bar crests, whereas the finest grains are found in the lower energy, deeper interior and flanking regions. In short, results clearly document hydrodynamic‐bathymetrical influences on these ooid shoals and their granulometry, linkages akin to siliciclastic analogues. Sedimentological, hydrodynamic and geomorphic observations are consistent with a conceptual model for the formation of parabolic bars in which initial irregularities in non‐parabolic bars are enhanced through their effect of focusing flow. Constricted flow leads to higher flow velocities, tidal flow velocity asymmetries, differential net sediment transport and growth of bathymetrical highs. This bathymetrical divergence creates separate paths for flood‐ and ebb‐tides, facilitating emergence of better‐developed parabolic forms. The resultant parabolic geometries and component bedforms appear to be either in dynamic equilibrium with both ebb‐ and flood‐tide flows, or evolving toward that state. In exploring patterns and processes within carbonate shoals, this study illustrates some of the first documented insights on quantitative details of morphology and dynamics and in the links between geomorphic framework and grain‐size and sorting in an oolitic carbonate system. Assuming a continuity of processes between ancient and modern, the insights from this shoal provide information on possible facies geometries and on the characteristics of grains and depositional porosity of analogous facies within ancient ooid shoals.
Evolution of a Holocene delta driven by episodic sediment delivery and coseismic deformation, Puget Sound, Washington, USA
Authors: BARNHARDT WALTER A. , SHERROD BRIAN L. 
Published: November 2006

AbstractEpisodic, large‐volume pulses of volcaniclastic sediment and coseismic subsidence of the coast have influenced the development of a late Holocene delta at southern Puget Sound. Multibeam bathymetry, ground‐penetrating radar (GPR) and vibracores were used to investigate the morphologic and stratigraphic evolution of the Nisqually River delta. Two fluvial–deltaic facies are recognized on the basis of GPR data and sedimentary characteristics in cores, which suggest partial emplacement from sediment‐rich floods that originated on Mount Rainier. Facies S consists of stacked, sheet‐like deposits of andesitic sand up to 4 m thick that are continuous across the entire width of the delta. Flat‐lying, highly reflective surfaces separate the sand sheets and comprise important facies boundaries. Beds of massive, pumice‐ and charcoal‐rich sand overlie one of the buried surfaces. Organic‐rich material from that surface, beneath the massive sand, yielded a radiocarbon age that is time‐correlative with a series of known eruptive events that generated lahars in the upper Nisqually River valley. Facies CF consists of linear sandbodies or palaeochannels incised into facies S on the lower delta plain. Radiocarbon ages of wood fragments in the sandy channel‐fill deposits also correlate in time to lahar deposits in upstream areas. Intrusive, sand‐filled dikes and sills indicate liquefaction caused by post‐depositional ground shaking related to earthquakes. Continued progradation of the delta into Puget Sound is currently balanced by tidal‐current reworking, which redistributes sediment into large fields of ebb‐ and flood‐oriented bedforms.
Geochemical and Nd isotope composition of detrital sediments on the north margin of the South China Sea: provenance and tectonic implications
Authors: YAN YI , XIA BIN , LIN GE , CARTER ANDY , HU XIAOQIONG , CUI XUEJUN , LIU BAOMING , YAN PIN , SONG ZHENGJIANG 
Published: November 2006

AbstractA major re‐organization of regional drainages in eastern Tibet and south‐western China took place in the Cenozoic as deformation from the growing Himalayas and Tibetan Plateau affected an increasingly wider area. The effects of these changes on the regional sediment routing systems is not well constrained. This study examines the geochemical and Nd signatures of sedimentary rocks from the Ying‐Qiong and Nanxiong basins on the northern margin of the South China Sea to constrain and identify any significant changes in sediment source. Upper Cretaceous to Lower Eocene sedimentary rocks in the Nanxiong Basin show higher Th/Sc, La/Sc, Th/Cr and Th/Co ratios and lower Eu/Eu* ratios than PAAS (post‐Archaean Australian Shale), which indicates that Palaeozoic sedimentary rocks of the South China Block were the main basin sediment source. In contrast, Oligocene to Pleistocene sedimentary rocks of the Ying‐Qiong Basin show an abrupt change in these trace‐element ratios between 16·3 and 10·4 Ma, indicating a mid‐Miocene shift in provenance. ɛNd values from the Ying‐Qiong Basin (range = −11·1 to −2·1) reinforce this, with pre‐13·8 Ma sedimentary rocks having average ɛNd of −5·6 (range = −2·1 to −7·4), and post‐13·8 Ma sedimentary rocks having average ɛNd of −9·3 (range = −8·7 to −11·1). During the Oligocene, the centre of rifting transferred south and basins on the north margin of the South China Sea experienced rapid subsidence. Further uplift and erosion then exposed Mesozoic and Cenozoic granites that supplied large amounts of granitic detritus, especially to the Ying‐Qiong Basin. Then a change occurred at ca 13 Ma resulting in less input from local sources (i.e. the fault blocks formed by Mesozoic‐Cenozoic tectonics and magmatism) to an increasing contribution of older continental material, mostly from Indochina to the west of the South China Sea.
Lithofacies and origin of late Quaternary mass transport deposits in submarine canyons, central Scotian Slope, Canada
Authors: JENNER KIMBERLEY A. , PIPER DAVID J. W. , CAMPBELL D. CALVIN , MOSHER DAVID C. 
Published: November 2006

AbstractMass transport deposits, up to 3·9 m thick, have been identified from piston cores collected from canyon floors and inter‐canyon ridges on the central Scotian Slope. These deposits are characterized by four distinct mass‐transport facies – folded mud, dipping stratified mud, various types of mud‐clast conglomerate, and diamicton. Commonly, the folded and stratified mud facies are overlain by mud‐clast conglomerate, followed by diamicton and then by turbidity current deposits of well‐sorted sand. Stratified and folded mud facies were sourced from canyon walls. Overconsolidation in clasts in some mud‐clast conglomerates indicates that the source sediment was buried 12–33 m, much deeper than the present cored depth, implying a source in canyon heads and canyon walls. The known stratigraphic framework for the region and new radiocarbon dating suggests that there were four or five episodes of sediment failure within the past 17 ka, most of which are found in more than one canyon system. The most likely mechanism for triggering occasional, synchronous failures in separate canyons is seismic ground shaking. The facies sequence is interpreted as resulting from local slides being overlain by mud‐clast conglomerate deposits derived from failures farther upslope and finally by coarser‐grained deposits resulting from retrogressive failure re‐mobilizing upper slope sediments to form debrisflows and turbidity currents.
Holocene evolution of the Anichab Pan on the south‐west coast of Namibia
Authors: COMPTON JOHN S. 
Published: November 2006

AbstractCoastal sediment‐filled depressions (pans) are one of the few areas that contain Quaternary records of sea‐level and palaeoenvironmental change along the western margin of southern Africa. Anichab is a 128 km2 salt‐encrusted pan on the hyper‐arid southern coast of Namibia with an emergent, well‐preserved and in‐place mid‐Holocene mollusc assemblage. The molluscs are typical of subtidal sands on the sheltered side of offshore islands but include several warm‐water species no longer found living along this coast. The Holocene evolution of the pan was largely influenced by changes in sea level and supply of sand along the coast. Calibrated radiocarbon ages of mollusc shells indicate a maximum Holocene sea level of ca 2 m above mean sea level (msl) from 7·0 to 6·3 ka and a return to near present‐day sea level by 5·3 ka. The pan surface is 2 m below msl and has been emergent since 4·9 ka from the build up of sandy beaches and coastal dunes. A thin (1–4 cm) halite crust occurs over much of the pan surface but a layer of halite‐cemented sand up to 40 cm thick is restricted to the central pan. Gypsum occurs near the subsurface brine interface and is limited by calcium to the edges of the pan. Nodules of calcite‐cemented sand are forming in brackish, relatively high alkalinity subsurface waters in the south‐east corner of the pan and nodules of aragonite‐cemented sand are forming in brines 1 m below the central pan surface. Although modern dolomite has been reported from coastal lagoons of Brazil and Australia, carbonate cements are a minor feature of Anichab Pan and dolomite was restricted to a single reworked nodule most likely of Late Pleistocene age. Therefore, Anichab Pan does not appear to be a modern analogue to extensive, mixed‐water dolomite cements found in Upper Pleistocene sediment‐filled depressions on the Namibian shelf.
Factors affecting the nature and rate of dust production from natural dune sands
Authors: BULLARD JOANNA E. , MCTAINSH GRANT H. , PUDMENZKY CHRISTA 
Published: November 2006

AbstractThis paper evaluates the influence of natural sand particle characteristics on the amount and particle‐size distributions of dust produced by aeolian abrasion. It contrasts with previous studies of aeolian abrasion by conducting experiments using: (i) whole sand samples, as opposed to selected size fractions; (ii) natural, mature dune sands, rather than artificial or freshly crushed material; and (iii) weathered sands that have acquired a superficial clay coating, instead of grains with clean surfaces. Whilst previous research has found clear, positive relationships between particle size, sorting, roundness and the amount of dust produced by aeolian abrasion, the relationships determined in this study show some variation according to the geomorphological context from which the original samples were obtained. The most important factor affecting the amount and particle‐size characteristics of the dust produced was the presence of a clay coating on the grain surface that is removed by the abrasion process. The dust produced by this mechanism had a modal size of 2–5 μm and material <10 μm comprised up to 90% of the particles produced.
Formation and preservation of open‐framework gravel strata in unidirectional flows
Authors: LUNT I. A. , BRIDGE J. S. 
Published: November 2006

AbstractOpen‐framework gravel (OFG) in river deposits is important because of its exceptionally high permeability, resulting from the lack of sediment in the pore spaces between the gravel grains. Fluvial OFG occurs as planar strata and cross strata of varying scale, and is interbedded with sand and sandy gravel. The origin of OFG has been related to: (1) proportion of sand available relative to gravel; (2) separation of sand from gravel during a specific flow stage and sediment transport rate (either high, falling or low); (3) separation of sand from gravel in bedforms superimposed on the backs of larger bedforms; (4) flow separation in the lee of dunes or unit bars. Laboratory flume experiments were undertaken to test and develop these theories for the origin of OFG. Bed sediment size distribution (sandy gravel with a mean diameter of 1·5 mm) was kept constant, but flow depth, flow velocity and aggradation rate were varied. Bedforms produced under these flow conditions were bedload sheets, dunes and unit bars. The fundamental cause of OFG is the sorting of sand from gravel associated with flow separation at the crest of bedforms, and further segregation of grain sizes during avalanching on the steep lee side. Sand in transport near the bed is deposited in the trough of the bedform, whereas bed‐load gravel avalanches down the leeside and overruns the sand in the trough. The effectiveness of this sorting mechanism increases as the height of the bedform increases. Infiltration of sand into the gravel framework is of minor importance in these experiments, and occurs mainly in bedform troughs. The geometry and proportion of OFG in fluvial deposits are influenced by variation in height of bedforms as they migrate, superposition of small bedforms on the backs of larger bedforms, aggradation rate, and changes in sediment supply. If the height of a bedform increases as it migrates downstream, so does the amount of OFG. Changes in the character of OFG on the lee‐side of unit bars depend on grain‐size sorting in the superimposed bedforms (dunes and bedload sheets). Thick deposits of cross‐stratified OFG require high bedforms (dunes, unit bars) and large amounts of aggradation. These conditions might be expected to occur during high falling stages in the deeper parts of river channels adjacent to compound‐bar tails and downstream of confluence scours. Increase in the amount of sand supplied relative to gravel reduces the development of OFG. Such increases in sand supply may be related to falling flow stage and/or upstream erosion of sandy deposits.