44 research outputs found
Challenges encountered during acid resin transfer preparation of fossil fish from Monte Bolca, Italy
Copyright: Palaeontological Association May 2015.
This is an open access article, available to all readers online, published under a creative commons licensing (https://creativecommons.org/licenses/by/4.0/). The file attached is the published version of the article
Cleaning Minerals: practical and ethical considerations
Mineral specimens have a dual nature, both as a scientific resource and an aesthetic pleasure. Combine this with a long history of sampling for study, and the developed nature of most specimens on the commercial market, and it is difficult to relate to the ethical principles of conservation when cleaning minerals.The attached document is the authorâs final accepted/submitted version of the journal article. You are advised to consult the publisherâs version if you wish to cite from it
âHopeâ is the thing with feathers: how useful are cyclomethicones when cleaning taxidermy?
Silicone solvents have extreme hydrophobicity so they can be used as a temporary barrier to aqueous cleaning solutions. They are characterised as having low odour, moderately low toxicity, low polarity and surface tension. They are 100% volatile so will leave no trace behind. Silicone solvents could potentially be used to flood the skin of taxidermy specimens, to provide a barrier whilst fur or feathers are cleaned, and even permit the use of heat treatments without causing damage to the skin. They will not cause drying or swelling and will not dissolve or mobilise any skin components such as dyes or fats, which would normally be adversely affected by water or other solvents. They are also, in theory, safe to use on skin which has suffered so much deterioration that the shrinkage temperature is close to room temperature. Different classes of silicone solvents have different working times and this article explores 3 of these, and their practical applicability when cleaning taxidermy.NatSCA Notes & Comments is published by the Natural Sciences Collections Association (NatSCA) and distributed under a Creative Commons Attribution 4.0 International Licence (CC BY 4.0; https://creativecommons.org/licenses/by/4.0/). Works can be shared and adapted for any purpose, including commercially. CC BY 4.0 allows maximum dissemination, which is integral to the aims of NatSCA. All authors retain the copyright in their work
Conservation of James Sowerbyâs Fungi Models
NatSCA supports open access publication as part of its mission is to promote and support natural science collections. NatSCA uses the Creative Commons Attribution License (CCAL)
http://creativecommons.org/licenses/by/2.5/ for all works we publish. Under CCAL authors retain ownership of the copyright for their article, but authors allow anyone to download, reuse, reprint, modify, distribute, and/or copy articles in NatSCA publications, so long as the original authors and source are cited. The attached version is the published pdf
Snagged setae: evaluating alternatives to cotton wool bungs for liquid-stored specimens
Society for the Preservation of Natural History Collections Copyright © 2018. All rights reserved. Article is available as open access. The attached file is the published pdf version
Conservation in a Barcode Age: A cross-discipline re-storage project for pyritic specimens
The dichotomy of conservation and access has long been recognised within the museum profession. The recent push for digitisation has added a new dimension to this argument: digital records can both increase potential access, due to increased awareness of the existence of objects, and decrease potential handling, since a more thorough awareness of an object creates a more informed decision regarding whether access is actually necessary. The use of barcodes and the creation of digital resources have therefore been incorporated into a re-storage project at the Natural History Museum, London to reduce duplication of work (and handling) by staff and to combat the reduction in access caused by the enclosure of objects within microenvironments, which in turn helps preserve specimens for future access. This project demonstrates how conservation and digitisation can successfully synthesise through the use of barcodes, when working with a cross-discipline team.This publication from ICOM-CC is "Open Accessâ and licensed by the respective authors. This license allows for unlimited distribution and reuse as long as appropriate credit is given to the original source
The Airless Project
A project to combat pyrite oxidation at the NHM (London, UK) is currently in its second year. The project aims to undertake conservation treatments and store highest risk specimens in low oxygen microenvironments. An emergent benefit of the conservation-driven project has been the digitisation of specimens on the collection management system KE Emu, through the use of barcodes and web-based applications.This is a poster presented at Evolving Ideas: Provocative new ways of working with collections
(Natural Sciences Collections Association Conference). Cambridge, UK, 20â21 April 2017. NatSCA supports open access publication as part of its mission is to promote and support natural science collections. NatSCA uses the Creative Commons Attribution License (CCAL) for all works we publish. Under CCAL authors retain ownership of the copyright for their article, but authors allow anyone to download, reuse, reprint, modify, distribute, and/or copy articles in NatSCA publications, so long as the original authors and source are cited
Giant Sequoia: an extraordinary case study involving CarbopolÂź gel
In 2016 a project was undertaken to stabilise and aestheticise the transverse section of giant sequoia on display at the Natural History Museum (NHM) in London, UK. This iconic specimen, which now dominates the top floor of the central hall, was 1300 years old when felled and has been part of the exhibitions for 122 years. Measuring over 4.5 metres in diameter, it posed many challenges during remedial conservation. The largest involved removal of the discoloured waxy substance and opacified shellac-based varnish that had been applied in the early 1980s. Solvent tests revealed that the coating was soluble in Industrial Methylated Spirits (IMS) and that the gel worked most effectively at a 1 hour application time. At longer durations the varnish itself gelled and the waxy component was re-deposited. The waxy substance was effectively removed by wiping with alternate white spirit and IMS swabs.The attached file is the final accepted manuscript version of a presentation given at Gels in Conservation conference, London 16 - 18 October 2017. The link is to the video of the presentation and the published version is available in the printed proceedings. The photographs appear here by courtesy of the authors
The detection and X-ray evolution of galaxy groups at high redshift
We describe some of the first X-ray detections of groups of galaxies at high
redshifts (z~0.4), based on the UK deep X-ray survey of McHardy et al (1998).
Combined with other deep ROSAT X-ray surveys with nearly complete optical
identifications, we investigate the X-ray evolution of these systems. We find
no evidence for evolution of the X-ray luminosity function up to z=0.5 at the
low luminosities of groups of galaxies and poor clusters (Lx>3e42 erg/s),
although the small sample size precludes very accurate measurements. This
result confirms and extends to lower luminosities current results based on
surveys at brighter X-ray fluxes. The evolution of the X-ray luminosity
function of these low luminosity systems is more sensitive to the thermal
history of the intra-group medium (IGM) than to cosmological parameters. Energy
injection into the IGM (from for example supernovae or AGN winds) is required
to explain the X-ray properties of nearby groups. The observed lack of
evolution suggests that the energy injection occured at redshifts z>0.5.Comment: 13 pages, MNRAS accepte
Galaxy colours in high redshift X-ray selected clusters - I: Blue galaxy fractions in eight clusters
We present initial results from a wide-field, multi-colour imaging project,
designed to study galaxy evolution in X-ray selected clusters at intermediate
(z~0.25) and high redshifts (z~0.5). In this paper we give blue galaxy
fractions from eight X-ray selected clusters, drawn from a combined sample of
three X-ray surveys. We find that all the clusters exhibit excess blue galaxy
populations over the numbers observed in local systems, though a large scatter
is present in the results. We find no significant correlation of blue fraction
with redshift at z>0.2 although the large scatter could mask a positive trend.
We also find no systematic trend of blue fraction with X-ray luminosity. We
show that the blue fraction is a function of (a) radius within a cluster, (b)
absolute magnitude and (c) the passbands used to measure the colour. We find
that our blue fractions (f_b) from galaxy colours close to restframe (U-B),
f_b~0.4, are systematically higher than those from restframe (B-V) colours,
f_b~0.2. We conclude this effect is real, may offer a partial explanation of
the widely differing levels of blue fraction found in previous studies and may
have implications for biases in optical samples selected in different bands.
While the increasing blue fraction with radius can be interpreted as evidence
of cluster infall of field galaxies, the exact physical processes which these
galaxies undergo is unclear. We estimate that, in the cores of the more massive
clusters, galaxies should be experiencing ram--pressure stripping of galactic
gas by the intra--cluster medium. The fact that our low X-ray luminosity
systems show a similar blue fraction as the high luminosity systems, as well as
a significant blue fraction gradient with radius, implies other physical
effects are also important.Comment: Accepted for publication in MNRA