scholarly journals Scanning Electron Microscopy as a Tool to Observe the Effects of Simulated Conservation Treatment on Herbarium Specimens

2018 ◽  
Vol 2 ◽  
pp. e26093
Author(s):  
Magdalena Grenda-Kurmanow
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Dna Analysis ◽  
Genetic Material ◽  
Methyl Cellulose ◽  
Herbarium Specimens ◽  
Conservation Treatment ◽  
Wild Strawberry ◽  
Materials Used ◽  
Scanning Electron

This paper presents the Scanning Electron Microscopy (SEM) observations conducted for the project "Heritage preservation and ethnobotany. Analysis of the influence of conservation treatment on genetic material comprised in historic herbaria“ (project no. 2014/13/N/HS2/03118) funded by the National Science Centre in Poland. The main aim of the project is to establish if treatment methods used by herbarium conservators and mounters in different countries are harmful for the DNA material comprised in herbarium specimens. In order to analyse this problem the author conducted an international survey among specialists with documented experience in herbarium treatment. The next step was the evaluation of the results and the choice of materials. The chosen materials were then applied to samples of herbarium specimens, artificially aged in the climatic chamber, and subjected to DNA analysis. The results of the survey illustrated the variety of the materials used to treat and mount specimens. Some of them, such as methyl cellulose, were used in different concentrations and different degrees of polymerization. The project limitations determined the selection of materials for further testing, particularly when it comes to the concentration of a particular adhesive/consolidant. At the same time the main assumption was to identify versions of the material that can effectively penetrate the specimen in order to intensify the potential influence on its DNA. Dessicated plant specimens are not a common material in conservation research because their structure is highly heterogenic, fragile and brittle. Moreover, the materials used for mounting and conservation treatment are most often adapted from bookbinding and paper conservation disciplines. They are not always suitable for the treatment of botanic material and may cause damage. When observations of stratigraphic samples under a traditional microscope proved unsatisfactory, the potential of SEM imaging was examined. SEM turned out to be a very useful tool to observe the effects of simulated conservation treatments conducted on herbarium specimen samples, but only when samples were coated with gold. The conclusions from these observations informed decisions about what versions of the conservation and mounting materials should be used for further testing. Additionally, some samples were observed after artificial aging in aclimatic chamber. It enabled us to observe the degradation of the layers of materials applied onto the specimens. The analysis focussed on the leaves of two species, Fragaria vesca (wild strawberry) and Arabidopsis thaliana (thale cress).

Comparative Study of Acid Etching on Dental Enamel

2018 ◽  
Vol 69 (10) ◽  
pp. 2913-2915
Author(s):  
Daniela Jumanca ◽  
Anamaria Matichescu ◽  
Atena Galuscan ◽  
Laura Cristina Rusu ◽  
Cornelia Muntean
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Experimental Study ◽  
Orthophosphoric Acid ◽  
Dental Enamel ◽  
Acid Etching ◽  
Sealing Material ◽  
Mechanical Bond ◽  
Materials Used ◽  
Scanning Electron

This experimental study aims to analyse the effectiveness of various materials used in demineralisation of dental enamel. This work aims to create a mechanical bond by filling the pegs with sealing material. In order to achieve this goal, five teeth were compared using different concentrations of orthophosphoric acid and exposure times. In this regard, five different tests were performed and the results were analysed using the SEM technique (scanning electron microscopy). These comparative analyses revealed that etching using 35% orthophosphoric acid for one minute and etching using Icon Etch for two minutes were the most effective.

scholarly journals Adhesives and the Herbarium: International Survey and Application of the Results in Analysis of the Influence of Conservation Materials on DNA of Herbarium Specimens

2018 ◽  
Vol 2 ◽  
pp. e25583
Author(s):  
Magdalena Grenda-Kurmanow
Keyword(s):  
Genetic Material ◽  
Daily Basis ◽  
Wheat Starch ◽  
Rice Starch ◽  
Herbarium Specimens ◽  
International Survey ◽  
Heritage Preservation ◽  
Conservation Treatment ◽  
Materials Used ◽  
Starch Paste

In 2017 the author conducted an international survey among the conservators who have worked with herbaria collections, particularly paper conservators who treated historic herbaria. During the survey the author contacted 25 people from 9 countries. The participants were the conservators who either shared their experience through publications or whose conservation reports were available to the author. Participants were asked to recommend materials used in the conservation of historic herbaria and materials used on a daily basis to mount specimens. The aim of the survey was to list the materials that have direct contact with the surface of the specimens. Therefore the results concentrated mostly on adhesives. Acknowledging that materials recommended for conservation treatment may differ from those used for a typical mounting of a modern specimen, the author presented a traditional conservator’s approach that every modern object (including herbaria) may one day become a valuable part of heritage. This means that all materials used when working with herbaria should be reversible and DNA-safe. The survey revealed that most conservators recommend materials that are very popular in paper conservation: wheat starch paste and methylcellulose at different concentrations, however some suggested using animal glues such as gelatine or isinglass and mixtures of isinglass and starch paste. Other adhesives that were present in the results were two versions of hydroxypropylcellulose, Klucel G and Klucel E, rice starch, shofu, and different PVAs used for mounting (e.g. Hewit M218 and Jade 403). Many conservators expressed their negative approach to popular mounting materials and techniques of mounting by overall adhesion. The survey was a part of the project "Heritage preservation and ethnobotany. Analysis of the influence of conservation treatment on genetic material comprised in historic herbaria“ (project no. 2014/13/N/HS2/03118) funded by the National Science Centre in Poland. The results of the survey served as a basis for the next stage of the project, which was testing samples of herbarium specimens, 'treated' with the chosen materials, for the possible damaging influence on the DNA of specimens. The choice of materials based on the results of the survey, literature and availability of materials (some adhesives used for mounting some decades ago are no longer available). The herbarium samples were made of Arabidopsis thaliana and Fragaria vesca leaves, prepared for the project. After drying and 'treating' with conservation and mounting materials, the samples were artificially aged in a climatic chamber to imitate deterioration processes.

Setal morphology in cirripedes: a useful tool in phylogenetic studies?

2011 ◽  
Vol 92 (2) ◽  
pp. 305-325 ◽  
Author(s):  
L.J. Walley
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Shell Structure ◽  
Deep Sea ◽  
Littoral Zone ◽  
Dna Analysis ◽  
Soft Body ◽  
Barnacle Species ◽  
Phylogenetic Studies ◽  
Scanning Electron

The morphology of the setae, on the mouthparts and the cirri of 33 barnacle species, was investigated by scanning electron microscopy. The species examined were selected from a range of pedunculate and balanomorph families living in a variety of habitats from the littoral zone to deep-sea vents. It was found that the setae could be divided into five groups: simple, denticulate, setulate, plumo-denticulate and aesthetascs. The categories were subdivided resulting in 43 setal types being recognized. Balanomorph cirripedes were found to have a greater variety of setae than pedunculates. Setulate setae on the cirri, and specialized setae on the mandibular palps and the first maxillae tended to be associated with the development of the balanomorph form. Setal type was correlated with taxonomy, whether based on shell structure and soft body morphology or DNA analysis, but with some anomalies which deserve further investigation. The problems of reconciling the proposed cirripede setal categories with those described in the Decapoda are discussed.

scholarly journals Morphological and genetic evidence supports the separation of two Tapinoma ants (Formicidae, Dolichoderinae) from the Atlantic Forest biome

ZooKeys ◽  
2021 ◽  
Vol 1033 ◽  
pp. 35-62
Author(s):  
Mayron E. Escárraga ◽  
John E. Lattke ◽  
Marcio R. Pie ◽  
Roberto J. Guerrero
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Atlantic Forest ◽  
Dna Analysis ◽  
Morphological Characteristics ◽  
Genetic Evidence ◽  
Morphological Evidence ◽  
Head Shape ◽  
Scanning Electron ◽  
Forest Biome

The taxonomic boundaries of many Neotropical ant species of the genus Tapinoma are still unclear. Tapinoma atriceps and T. atriceps breviscapum are two morphologically similar taxa which occur sympatrically in the southern Atlantic Forest of Brazil. Some characters such as the scape length and head shape suggest that these taxa may be different species. We used DNA analysis and morphological evidence, including scanning electron microscopy, to evaluate the taxonomic validity of these taxa. We found distinct morphological characteristics that allow separating them as two different species, Tapinoma atriceps and Tapinoma breviscapumstatus novo, and this decision is supported by the DNA results, where Tapinoma atriceps was recovered as a lineage independent of T. breviscapum.

Microchemical Studies of Tuyeres and Refractory Materials used by Phoenicians and Punics at Tharros (Sardinia, Italy)

1996 ◽  
Vol 462 ◽  
Author(s):  
G.M. Ingo ◽  
E. Acquaro ◽  
L-I. Manfred ◽  
G. Bultrini ◽  
G. Chiozzini ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Smelting Process ◽  
Refractory Materials ◽  
Thermal Treatments ◽  
X Ray ◽  
Reducing Atmosphere ◽  
Iron Smelting ◽  
Materials Used ◽  
Scanning Electron

ABSTRACTA large amount of smelting slags, tuyeres and curved refractory materials used during pyrometallurgical activities have been found at Tharros (western-Sardinia, Italy) during an excavation stratigraphically related to the Phoenician-Punic period (VI-IV BC). The microchemical structure of the vitrified end of tuyeres and of the thick fragments of the smelting furnaces, has been studied by means of scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDS). The results indicate that these materials can be associated with an iron smelting process. Furthermore, the temperature and duration of the smelting process has been estimated from the study of vitrification process and penetration depth of vitrification of the tips of some tuyeres combined with the study of pieces of clay taken from a unverified fragment of a tuyere and subjected to different thermal treatments under reducing atmosphere.

A Study of the Materials of Pontormo's “Portrait of Alessandro de' Medici”

2004 ◽  
Vol 852 ◽  
Author(s):  
Ken Sutherland ◽  
Beth A. Price ◽  
Irma Passeri ◽  
Mark Tucker
Keyword(s):  
Electron Microscopy ◽  
Mass Spectrometry ◽  
Scanning Electron Microscopy ◽  
Gas Chromatography ◽  
Gas Chromatography Mass Spectrometry ◽  
Infrared Microspectroscopy ◽  
Fourier Transform Infrared Microspectroscopy ◽  
Materials Used ◽  
Scanning Electron

ABSTRACTIn studies of the materials of old master paintings, the characterization of thin and degraded layers often presents unusual challenges for routinely used methods of analysis. This paper discusses analyses performed as part of a study of the materials and techniques of Pontormo's “Portrait of Alessandro de’ Medici” (1534–5) carried out during a recent cleaning and restoration of the painting. Pontormo built up the portrait using a complex sequence of preparation, drawing and paint layers, the analysis of which was complicated further in some areas by the presence of degraded materials on the paint surface. The materials used for the various stages of preparation and painting were characterized by gas chromatography/mass spectrometry (GCMS), Fourier transform infrared microspectroscopy (FTIR) and scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). The focus of this paper will be the particular approaches taken to the characterization of the preparation layers and degraded surface materials.

The characterization of lead smelter dusts by automated scanning electron microscopy

1992 ◽  
Vol 50 (2) ◽  
pp. 1492-1493
Author(s):  
Tim B. Vander Wood
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Particle Size ◽  
Sinter Plant ◽  
Water Solution ◽  
Methyl Cellulose ◽  
Dust Sample ◽  
Lead Smelter ◽  
Automated Scanning ◽  
Scanning Electron

The dust derived from smelting and other mining/metallurgical processes is increasingly viewed as a resource rather than a hazardous waste. In order to determine the most appropriate technologies for resource recovery from these dusts and other hazardous wastes, they must be examined in some detail for particle size, chemistry, phase composition, etc. Automated scanning electron microscopy combined with energy-dispersive x-ray spectrometry (ASEM-EDS) provides a tool for rapidly determining the particle size distribution and chemistry on a representative dust sample so that the most appropriate processing methods can be chosen.ASEM-EDS analyses were performed on five dust samples that had previously been examined by traditional techniques of ore microscopy. Each sample was from a distinct area of the Herculaneum Lead Smelter: 1) Blast Furnace Area, #2) Dross Furnace Area, #3) Refinery Area, 4) Sinter Plant near the scrubber and #5) Sinter Plant near the crusher. Approximately 200 mg of each dust were dispersed in 100 ml of 20 ppm methyl cellulose/water solution, and a droplet of each dispersion was placed on a polished carbon planchet.

Leaves and epiphyllous shoots in Chisocheton (Meliaceae): a continuum of woody leaf and stem axes

1990 ◽  
Vol 68 (11) ◽  
pp. 2316-2328 ◽  
Author(s):  
Jack B. Fisher ◽  
Rolf Rutishauser
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Papua New Guinea ◽  
Related Species ◽  
Leaf Primordium ◽  
Axillary Buds ◽  
Herbarium Specimens ◽  
Small Tree ◽  
Scanning Electron ◽  
Epiphyllous Buds

The pinnately compound leaves of Chisocheton tenuis, a small tree from Papua New Guinea, exhibit indeterminate growth and periodically produce new pinnae from a leaf tip bud. Inflorescences and vegetative shoots arise from epiphyllous buds on the adaxial surface of the rachis between the pinna pairs. Axillary buds occur on the stem but are always vegetative. The structure and ontogeny of leaves, axillary buds, and epiphyllous buds are documented with sections and scanning electron microscopy. Although epiphyllous inflorescences are described from herbarium specimens of C. tenuis, only vegetative shoots were collected as epiphyllous outgrowths. These epiphyllous shoots formed woody stem and rachis axes similar to the stem and rachis on the original shoot. Epiphyllous buds first appear on a leaf primordium without evidence of an ontogenetic displacement from an earlier axillary site. Later, epiphyllous buds and pinnae arise in an acropetal order close to the meristem at the tip of the leaf. Epiphyllous inflorescences in Chisocheton pohlianus are described from herbarium material. Leaf and bud structure and ontogeny in a related species, Chisocheton montanus, which lacks epiphyllous buds and has axillary inflorescences, are similar to C. tenuis except that no meristems occur on the rachis. Possible morphological interpretations for these examples of unusual organography are presented. Epiphyllous buds and leaf tip meristems are examples of heterotopy. Key words: buds, epiphylly, Chisocheton, heterotopy, homology, leaves, Meliaceae, meristems.

Hydathodes in Physocarpus (Rosaceae: Spiraeoideae)

1982 ◽  
Vol 60 (6) ◽  
pp. 850-855 ◽  
Author(s):  
Nels R. Lersten ◽  
John D. Curtis
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Anatomical Study ◽  
Bundle Sheath ◽  
Herbarium Specimens ◽  
Marginal Tooth ◽  
Adaxial Epidermis ◽  
Physocarpus Opulifolius ◽  
Tooth Apex ◽  
Scanning Electron

This is the first anatomical study of hydathodes from subfamily Spiraeoideae. Fresh leaves of Physocarpus opulifolius were cleared, or processed for paraffin and plastic sections and scanning electron microscopy. Each marginal tooth apex bears an achlorophyllous hydathode, which is visible adaxially as a smooth epidermal pad studded with 15–25 small, sunken "water pores" usually covered by an unbroken cuticle. Ordinary stomata are larger, raised, and abaxial. Internally, an epithem of small, loosely arranged cells extends from the adaxial epidermis to the laterally broadened, single vein ending. Bundle and epithem are bounded by the bundle sheath, which extends to the epidermis at the periphery of the pad. Guttation neither was seen naturally nor could it be induced. Cleared leaves of herbarium specimens of the six Physocarpus species showed all degrees of hydathode reduction to complete absence.

Conservation of the Lyre from Grave 48 in the Area between the So-Called ‘Eriai’ Gates and the Dipylon (470–50 BC)

2020 ◽  
Vol 8 (1) ◽  
pp. 45-62
Author(s):  
Vassiliki Milona
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Energy Dispersive Spectroscopy ◽  
Present Writer ◽  
Energy Dispersive ◽  
Conservation Treatment ◽  
Scanning Electron

Abstract This paper focuses on the conservation of the lyre (chelys) of Grave 48, from the area between the so-called ‘Eriai’ Gates and the Dipylon. First, it describes the lifting of the lyre (sound box) from the ground and the recovery of the fragile plaques and fragments from the compact block of soil in the laboratory. Subsequently, it presents the extensive conservation work undertaken by the present writer and her team. Furthermore, it summarizes the conclusions of the X-Radiography and Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM-EDS) examinations of the sound box and the string holder and provides information about the biochemistry, structure and decay of the tortoise shell. In conclusion, the collaboration between conservator and archaeomusicologist, during the remedial conservation treatment, was of great importance, and helped with the identification of the plaques and restoration of the lyre.

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