Using analytical pyrolysis and scanning electron microscopy to evaluate charcoal formation of four wood taxa from the caatinga of north-east Brazil

2020 ◽  
Vol 151 ◽  
pp. 104909 ◽  
Author(s):  
Diego Tamburini ◽  
Caroline R Cartwright ◽  
Peter Gasson ◽  
Jeannette Jacqueline Łucejko ◽  
Claudia Luizon Dias Leme
Phytotaxa ◽  
2018 ◽  
Vol 357 (2) ◽  
pp. 117 ◽  
Author(s):  
SAYED A. SHAH ◽  
AMIR SULTAN ◽  
JUN WEN ◽  
SURAT U. NISA ◽  
XU SU ◽  
...  

We here describe a new species, Vincetoxicum luridum, from South West Balochistan. Scanning electron microscopy (SEM) of leaves and seeds, palynology and chorology support the recognition of V. luridum. The lurid appearance, dense pubescence and ovate corona lobes readily distinguish V. luridum from the closely related species V. stocksii which is endemic to North East Balochistan. We illustrate V. luridum, and confirm the significance of corona morphology for classification of Vincetoxicum in Pakistan. Presently, the V. arnottianum complex comprise four species with purple flowers viz., V. arnottianum, V. sakesarense, V. luridum and V. stocksii. In this study we also present the geographic distribution and a taxonomic key to the taxa of V. arnottianum complex.


Author(s):  
Piotr Kuklinski ◽  
Paul D. Taylor

Study of type and other material using scanning electron microscopy has permitted the recognition of three new species and one new genus of Arctic and boreal calloporid anascans. Originally described from the Gulf of St Lawrence, Callopora whiteavesi is reassigned to Flustrellaria, a calloporid genus not previously reported extant. Material from north-east Greenland misidentified as C. whiteavesi is described as C. weslawski sp. nov. The new genus Septentriopora is introduced for calloporids lacking pore chambers, with a distolateral pair of small interzooidal avicularia that face proximally or proximolaterally, and a reduced ovicell. The type species of Septentriopora, Tegella nigrans, has frequently been misidentified. Many of the supposed records of this species belong to two other species, described here as Septentriopora karasi sp. nov. and S. denisenkoae sp. nov. The apparent ovicell in S. karasi is particularly unusual, being vestigial and kenozooid-like in morphology.


2018 ◽  
pp. 145-168
Author(s):  
Ester Oras ◽  
Ivar Leimus ◽  
Lauri Joosu

This chapter presents in full the small gold hoard from Essu, north-east Estonia, on the Vikings’ Austrvegr (eastern route). The hoard was found in a peat bog in the nineteenth century, and comprised six gold pendants dating to around the last quarter of the ninth century. This chapter provides a detailed analysis of the six pendants—one Arabic dinar-pendant and five pendants decorated with filigree and granulation—discussing their decoration and cultural parallels. Results from recent Scanning Electron Microscopy-Energy Dispersive X-Ray Spectroscopy (SEM-EDS) analysis cast new light on the pendants’ production, alloy content, and use-wear. It is suggested that the filigree pendants were manufactured within Scandinavia and originally formed part of an elaborate female necklace, while the dinar-pendant reached Estonia via the Nordic countries. Overall, the hoard illustrates the prominence of gold within the Viking Age display economy. The chapter concludes by discussing the significance of the hoard from a gender perspective, relating it to a wider group of Viking Age ritual deposits of gold female jewellery sets (so-called ‘themed deposits’).


2015 ◽  
Vol 95 (7) ◽  
pp. 1389-1394 ◽  
Author(s):  
Joana R. Xavier ◽  
Inês Tojeira ◽  
Rob W.M. Van Soest

Hexactinellids or glass sponges constitute a predominantly deep-sea sponge group typically occurring at bathyal and abyssal depths. Some species form dense populations along the European and African continental slope but the distribution and extent of these populations remains ill known and the driving factors behind their occurrence poorly understood. Here we report an aggregation of the hexactinellid sponge Poliopogon amadou Thomson, 1878 at ~2700 m depth on the Great Meteor seamount, a large seamount located southern of the Azores archipelago. A description of the species, along with scanning electron microscopy of its spicules, is provided.


Author(s):  
P.S. Porter ◽  
T. Aoyagi ◽  
R. Matta

Using standard techniques of scanning electron microscopy (SEM), over 1000 human hair defects have been studied. In several of the defects, the pathogenesis of the abnormality has been clarified using these techniques. It is the purpose of this paper to present several distinct morphologic abnormalities of hair and to discuss their pathogenesis as elucidated through techniques of scanning electron microscopy.


Author(s):  
P.J. Dailey

The structure of insect salivary glands has been extensively investigated during the past decade; however, none have attempted scanning electron microscopy (SEM) in ultrastructural examinations of these secretory organs. This study correlates fine structure by means of SEM cryofractography with that of thin-sectioned epoxy embedded material observed by means of transmission electron microscopy (TEM).Salivary glands of Gromphadorhina portentosa were excised and immediately submerged in cold (4°C) paraformaldehyde-glutaraldehyde fixative1 for 2 hr, washed and post-fixed in 1 per cent 0s04 in phosphosphate buffer (4°C for 2 hr). After ethanolic dehydration half of the samples were embedded in Epon 812 for TEM and half cryofractured and subsequently critical point dried for SEM. Dried specimens were mounted on aluminum stubs and coated with approximately 150 Å of gold in a cold sputtering apparatus.Figure 1 shows a cryofractured plane through a salivary acinus revealing topographical relief of secretory vesicles.


Author(s):  
Nakazo Watari ◽  
Yasuaki Hotta ◽  
Yoshio Mabuchi

It is very useful if we can observe the identical cell elements within the same sections by light microscopy (LM), transmission electron microscopy (TEM) and/or scanning electron microscopy (SEM) sequentially, because, the cell fine structure can not be indicated by LM, while the color is; on the other hand, the cell fine structure can be very easily observed by EM, although its color properties may not. However, there is one problem in that LM requires thick sections of over 1 μm, while EM needs very thin sections of under 100 nm. Recently, we have developed a new method to observe the same cell elements within the same plastic sections using both light and transmission (conventional or high-voltage) electron microscopes.In this paper, we have developed two new observation methods for the identical cell elements within the same sections, both plastic-embedded and paraffin-embedded, using light microscopy, transmission electron microscopy and/or scanning electron microscopy (Fig. 1).


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