843 research outputs found
Steering Taste: Ernest Marsh, a study of private collecting in England in the early 20th Century
No full textThe primary aim of this thesis is to focus attention on the bourgeois, 'un-named' collector. The driving force behind most museum and art gallery collections of the Victorian and Edwardian period. British museum and art gallery records of gifted collections, bequests and loans usually note their donors. However, with a few notable exceptions, little is known about the collectors, their activities and motivation in making such presentations.
Using the interests and activities of the Quaker miller and collector Ernest Marsh (1843-1945) as a case study, this thesis explores how in the period 1890-1945 a collector came to be a key agent in the construction and manifestation of taste in British Applied Arts and to a lesser degree in the Fine Arts. Through primary visual and documentary evidence of the Marsh home, and reference to contemporary and later commentaries it considers the relative influences of husband and wife on decorating and furnishing the domestic interior, the evolution of taste, and, for Ernest Marsh, its impact upon his artistic interests within the public arena.
By examination of private papers, metropolitan and provincial art gallery and museum archives it also considers evidence of the inter-relationships between donors and curators, and the mutual advantages and disadvantages accruing to both, particularly focussing on the processes in bringing about changes in individual and institutional collecting policy. Further, by review of records of, in particular, the Contemporary Art Society and the Greenslade archive, it examines the degree to which private benefactors and those in public or semi-public office, acting as fund-raisers and spenders exercise influence through patronage of particular practitioners, choice of works and initiating new designs
Bio-physical controls on tidal network geomorphology
No full textThe copyright of this thesis rests with the author and no quotation from it or information derived from it may be published without the prior written consent of the authorLooking over a tidal wetland, the tidal network characterised by its intricate system
of bifurcating, blind-ended tidal courses clearly stands out from the overall landscape.
This tidal landform exerts a fundamental control on the morphology and ecology within
the tidal environment. With today’s recognition of the ecological, economical and
societal values provided by tidal wetlands, which has been notably reflected in the
development of restoration management strategies across Europe and USA, there is
a need to fully understand the nature and development of tidal networks as well as
their relationships with associated landforms and biotic components (e.g. vegetation),
to eventually guarantee the success of current and future restoration practices. Accordingly,
this research aims to bring further insights into the bio-physical controls on
the geomorphology of tidal networks. To this end, a combination of remote sensing,
modelling and field activities was employed.
A geo-spatial analysis was performed at Queen Mary, University of London (UK), to
address the variability of tidal network patterns. A series of network scale morphometric
variables was extracted using airborne LiDAR data among selected tidal networks
across the UK depicting different planview morphologies, and supplemented with
the collection of corresponding marsh scale environmental variables from published
sources. Multivariate statistics were then performed to characterise the variability of
tidal network patterns and identify the inherent environmental controls. The analysis
has revealed that every network type can be characterised based upon measures of
network size and complexity, with each network pattern depicting proper morphometric
aspects. Particularly, the stream Strahler order and the median depth of the network
main channel have the highest discriminating weight on the patterns investigated. High
correlation between the latter variable and network main channel width has revealed
that linear, linear-dendritic and dendritic networks followed a transitional gradient in
their aspect ratio approximated by a power law and thus are seen to depict similar
erosional processes. To the contrary, meandering networks clearly depart from this relationship, and show particular segregation in their aspect ratios with respect to
dendritic networks. Globally, differentiation on network morphometric properties has
been linked to environmental conditions specific to the marsh physiographic setting
within which a tidal network develops. Conceptually, tidal networks seem to adapt to
marsh environmental conditions by adopting suitable morphologies to drain their tidal
basin effectively.
An eco-geomorphic modelling framework was developed at University of Trento
(Italy), to address tidal network morphological development. In line with current
theories as well as modelling advances and challenges in the field of tidal network
ontogeny, emphasis was thus placed on the investigation of tidal channel formation
and evolution in progressive marsh accretional context. Under these environmental
conditions, tidal network development can be ascribed to the combination of two
channel-forming processes: channel initiation results from bottom incisions in regions
where topographic depressions occur; channel elaboration results from differential
deposition, contributing to the deepening of the tidal channels relative to the adjacent
marsh platform. Further evolutionary stages including channel reduction proceed from
the horizontal progradation of the marsh platform which may lead eventually to channel
infilling. Moreover, both qualitative and quantitative results allude to an acceleration of
the morphological development of the synthetic tidal networks with increasing sediment
supply. These different observations thus emphasise the prevalence of depositional
processes in shaping tidal channels. In a second stage, the investigation was extended
to the role of the initial tidal flat morphology as an inherent control on tidal network
development, by considering different scenarios of topographic perturbations, which
has revealed its legacy on tidal network morphological features. Modelling experiments
have also acknowledged salt marsh macrophytes as a potential control on network
evolution depending on their biomass distribution within the tidal frame. However,
tidal channel morphodynamcis appears to be sensitive to the way biomass growth is
mathematically parameterised in the model.
In view of the current challenges in transcribing mathematically such a dynamic
process and the relevance of bio-physical interactions in driving salt marsh and tidal
network evolution, a field survey was conducted in a temperate salt marsh in the
Netherlands, as part of the mobility to UNESCO-IHE (Netherlands) in partnership with
University of Antwerp (Belgium), to assess vegetation distribution and productivity in
the tidal frame. Particularly, emphasis was placed on extending investigations on the possible presence of relationships involving vegetation properties in different climatic and ecological conditions from those characterising these previously documented
relationships. Regression analysis has revealed that biomass growth can be expressed
as a linear function of marsh relative elevation, providing therefore direct empirical
validation for corresponding assumptions reported in the literature and used in the
present modelling framework; surprisingly, that increase did not correlate with an
increase in species richness and diversity. Analysis of likely associations between
vegetation morphometrics and total standing biomass yielded only a single linear
relationship linking the latter variable to stem height. In truth, these observations may
bear reconsiderations on the global validity of the assumptions used in the formulation of some eco-geomorphic processes which are applied in the study and prediction of
wetland resiliency facing climate change
Marsh, Frank Lewis (1899–1992)
No full textFrank Lewis Marsh was the first Seventh-day Adventist to earn a Ph.D. in biology. He taught at several Adventist institutions and was the author of numerous articles and books in defense of young-earth creationism
Biotechnology in New Zealand: Description and analysis based on the 1998/99 and 2002 biotech surveys and a review of secondary sources
No full textThis paper provides a detailed description of the New Zealand biotechnology sector based on a re-analysis of the first comprehensive (1998/99) survey of biotechnology in New Zealand, data from an original (2002) survey conducted by the author and a detailed review of secondary sources. It provides the background for a study of the determinants of innovation reported elsewhere (Marsh, 2004). A review of alternative data sources on sector size and characteristics is followed by a comparison of New Zealand and international biotech indicators. Data is presented on enterprise type and size and the age distribution of New Zealand biotech enterprises. This is followed by an analysis of innovative output using data on new products, processes and patents. Data is also presented on partnerships and alliances, information sources and other factors affecting innovative performance
The AM Canum Venaticorum binary SDSS J173047.59+554518.5
No full textThe AM Canum Venaticorum (AM CVn) binaries are a rare group of hydrogen-deficient, ultrashort period, mass-transferring white dwarf binaries and are possible progenitors of Type Ia supernovae. We present time-resolved spectroscopy of the recently discovered AM CVn binary SDSS J173047.59+554518.5. The average spectrum shows strong double-peaked helium emission lines, as well as a variety of metal lines, including neon; this is the second detection of neon in an AM CVn binary, after the much brighter system GP Com. We detect no calcium in the accretion disc, a puzzling feature that has been noted in many of the longer period AM CVn binaries. We measure an orbital period, from the radial velocities of the emission lines, of 35.2 ± 0.2 min, confirming the ultracompact binary nature of the system. The emission lines seen in SDSS J1730 are very narrow, although double-peaked, implying a low-inclination, face-on accretion disc; using the measured velocities of the line peaks, we estimate i ≤ 11°. This low inclination makes SDSS J1730 an excellent system for the identification of emission lines
BIOPHYSICAL CONTROLS OF MARSH SOIL SHEAR STRENGTH ALONG AN ESTUARINE SALINITY GRADIENT
No full text© The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Gillen, M. N., Messerschmidt, T. C., & Kirwan, M. L. Biophysical controls of marsh soil shear strength along an estuarine salinity gradient. Earth Surface Dynamics, 9(3),(2021): 413-421, https://doi.org/10.5194/esurf-9-413-2021.Sea-level rise, saltwater intrusion, and wave erosion threaten coastal marshes, but the influence of salinity on marsh erodibility remains poorly understood. We measured the shear strength of marsh soils along a salinity and biodiversity gradient in the York River estuary in Virginia to assess the direct and indirect impacts of salinity on potential marsh erodibility. We found that soil shear strength was higher in monospecific salt marshes (5–36 kPa) than in biodiverse freshwater marshes (4–8 kPa), likely driven by differences in belowground biomass. However, we also found that shear strength at the marsh edge was controlled by sediment characteristics, rather than vegetation or salinity, suggesting that inherent relationships may be obscured in more dynamic environments. Our results indicate that York River freshwater marsh soils are weaker than salt marsh soils, and suggest that salinization of these freshwater marshes may lead to simultaneous losses in biodiversity and erodibility.This research has been supported by the US National Science Foundation (grant nos. 1654374, 1426981, 1529245, and 1832221)
Water regimes and marsh distribution. In: McComb, A.J., Kobryn, H.T. and Latchford, J.A. (eds) Samphire marshes of the Peel-Harvey estuarine system Western Australia.
No full textTide has long been recognised as the most influential factor determining plant zonation and the development of saltmarsh communities, and it is the tide that largely determines the structure and function of saltmarshes (Clarke & Hannon, 1969).
The zonation of species with increasing distance from the water's edge and increasing elevation is initially determined by the frequency of tidal flooding and the tolerance of various species to this (Huiskes, 1990). Tidal range usually sets the upper and lower limits of the marsh. The lower limits are set by depth and duration of flooding, and the consequent mechanical effect of the waves, sediment availability and rate of erosion. The upper limits are influenced mainly by soil water salinity and nutrient availability, both of which are linked to tidal flooding frequency (Mitsch & Gosselink, 1993), tidal water being the main source of soil salt and the major mechanism for nutrient transport (Clarke & Hannon, 1971)
Predicting marsh vulnerability to sea-level rise using Holocene relative sea-level data
No full textTidal marshes rank among Earth's vulnerable ecosystems, which will retreat if future rates of relative sea-level rise (RSLR) exceed marshes' ability to accrete vertically. Here, we assess the limits to marsh vulnerability by analyzing >780 Holocene reconstructions of tidal marsh evolution in Great Britain. These reconstructions include both transgressive (tidal marsh retreat) and regressive (tidal marsh expansion) contacts. The probability of a marsh retreat was conditional upon Holocene rates of RSLR, which varied between -7.7 and 15.2 mm/yr. Holocene records indicate that marshes are nine times more likely to retreat than expand when RSLR rates are ≥7.1 mm/yr. Coupling estimated probabilities of marsh retreat with projections of future RSLR suggests a major risk of tidal marsh loss in the twenty-first century. All of Great Britain has a >80% probability of a marsh retreat under Representative Concentration Pathway (RCP) 8.5 by 2100, with areas of southern and eastern England achieving this probability by 2040.Physical and Space Geodes
Pronounced inter-individual variation in plasma cortisol response to fluoxetine hydrochloride in the pig
No full textPublished: 18 March 2020Animal welfare assessment requires measures for positive affective state. Pharmacological agents that manipulate affective state can be used to evaluate novel biomarkers for affective state assessment. However, to validate that an agent has modified brain function, a reliable indicator is required. Circulating cortisol has been used as a reporter for effective delivery of the antidepressant selective serotonin reuptake inhibitor (SSRI) fluoxetine hydrochloride to the brain in humans and sheep. Here, we tested cortisol as a reporter for effective delivery of fluoxetine hydrochloride to the pig brain. We hypothesized that following administration of SSRI, innervation of the serotonergic reward pathway would result in activation of the hypothalamic-pituitary-adrenal (HPA) axis, leading to increased circulating cortisol levels. Large White-Landrace gilts received either a single intravenous dose of 100 mg fluoxetine hydrochloride suspended in 10 mL saline (n = 4), or 10 mL saline alone (n = 4). Blood samples were collected every 15 min for one hour prior to, and six hours post-treatment. The interaction of treatment x time on mean plasma cortisol levels between 15–165 min post-treatment was significant (p = 0.048) with highest cortisol concentrations of SSRI treated pigs versus controls (+ 98%) at 135 min post-treatment. However, individual cortisol profiles after SSRI treatment revealed high inter-individual variation in response. We conclude that, while combined data imply that plasma cortisol may be a readout for SSRI efficacy, inter-individual variation in SSRI response may preclude application of this approach in the pig. Given the current limited sample size, further research to confirm these findings is needed.Laura E. Marsh, Robyn Terry, Alexandra L. Whittaker, Stefan Hiendleder and Cameron R. Ralp
Cataclysmic variables from a ROSAT/2MASS selection. I, Four new intermediate polars
No full textWe report the first results from a new search for cataclysmic variables (CVs) using a combined X-ray (ROSAT)/infrared (2MASS) target selection that discriminates against background active galactic nuclei. Identification spectra were obtained at the Isaac Newton Telescope for a total of 174 targets, leading to the discovery of 12 new CVs. Initially devised to find short-period low-mass-transfer CVs, this selection scheme has been very successful in identifying new intermediate polars. Photometric and spectroscopic follow-up observations identify four of the new CVs as intermediate polars: 1RXS J063631.9+353537 P(orb)similar or equal to 201 min, P-spin= 1008.3408 s or 930.5829 s), 1RXS J070407.9+262501 (P(orb)similar or equal to 250 min, P-spin= 480.708 s) 1RXS J173021.5-055933 (P-orb= 925.27 min, P-spin= 128.0 s), and 1RXS J180340.0+401214 (P-orb= 160.21 min, P-spin= 1520.51 s). RX J1730, also a moderately bright hard X-ray source in the INTEGRAL/IBIS Galactic plane survey, resembles the enigmatic AE Aqr. It is likely that its white dwarf is not rotating at the spin equilibrium period, and the system may represent a short-lived phase in CV evolution
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