Guest Blog by Professor Andrew Nelson: On the Road with SA in the UK (Part 3, final installment)

Interested in how research projects and collaborations are established and executed? This is the final blog post in our series of three that has followed SA Research Associate Professor Andrew Nelson on a recent trip to the UK. Read Part 1 of the series here, and Part 2 here.

July 11^th – Andrew took the opportunity to visit the Nikon Metrology Centre-of-Excellence in Tring. Tring is about 40 minutes by train north of London. This is where the microCT scanners - including our own! - are assembled, and where Nikon offers inspection services using their line of scanners. Andrew Ramsey, a CT Specialist at Nikon, showed Andrew N. around, and patiently tolerated a barrage of questions about the inner workings of the CT Pro reconstruction software.  Andrew R. was part of the team that scanned the amazing 'mechanism' from the Antikythera shipwreck - and has lots of experience scanning interesting things!  

CT scanners being assembled at Nikon Metrology in Tring, England.

 July 12^th – Andrew visited the incredible block-buster exhibit at the British Museum entitled “Ancient lives:new discoveries”, featuring 8 Egyptian mummies [Andrew being a mummy expert himself - Ed.].  The exhibit features CT scans and detailed examinations of each individual, highlighting the story of their lives and how they were treated in death. Many of the exhibits included the ability for the visitor to interact with the scans – either rotating the views, cutting through the mummy or otherwise highlighting specific features. In many ways the exhibit was quite simple, but the visitors were enthralled.  This might be an interesting way to exhibit the scans of the prayer beads at the AGO!

July 14^th – Scan day.  Andrew linked up with Annie Kemkaran-Smith, to scan two objects from the Wernher Collection at Ranger’s House Museum in Greenwich. Annie is the Curator (Art Collections) of the National Collections Group with English Heritage, London. As such, she is the collections curator for Down House (Darwin’s home), Eltham Palace and Ranger’s House.

The objects were a small prayer bead and a miniature boxwood coffin – a memento mori (see an example of a very similar coffin at the Metropolitan Museum in New York, here).  The scans are pretty amazing – particularly the coffin!  It will take a lot of work with the analytical software to segment it into separate elements. We will demonstrate this work in a future blog post.

That was it for the bead and CT related work on this trip.  It was a pretty eventful few days!  We’ve got some more scanning planned at home in London, Ontario and the triptych with the Detroit Institute of the Arts to do – so lots more to come. Watch this space!

Thanks, Andrew, for sharing your adventures with us. It's been interesting to see where our microCT scanner was built, and the sorts of work researchers in the UK are doing with similar equipment. We are certain the trip has inspired research for both you and future students in the Anthropology Department at Western. We look forward to seeing your research and collaborations blossom here at SA: Western, and we're thrilled to be a part of this story!

Guest Blog by Professor Andrew Nelson: On the Road with SA in the UK (Part 2)

Interested in how research projects and collaborations are established and executed? This blog post continues the adventures of  SA Research Associate Professor Andrew Nelson, as he gives us a  behind-the-scenes look at his new collaborative project with the Art Gallery of Ontario. Read Part 1 of the series here.

July 8^th – Lisa Ellis, Sasha Suda (both of the AGO) and myself (Western University) visit the Natural History Museum in London, England to see their microCT scanning facility.  They have a Nikon XT225 just like the one at SA: Western – perfect for this project, as the unit and the software here will be the same that I use at home, ensuring comparability of the scans.  Lisa and Andrew, along with Andrew’s long time radiography colleague, Jerry Conlogue, met up at the NHM.  

Prof. Jerry Conlogue stands in front of a showcase of some of the projects produced by the IAC lab at the NHM.

There we were met by Dan Sykes, Assistant Micro-CT Lab Manager and Micro-CT Specialist at the Imaging and Analysis Centre (IAC). This is an amazing operation – a lab full of humming computers with folks creating amazing images on their computer screens – everything from bee brains to meteorites to bones. 

The Imaging and Analysis Centre at the Natural History Museum, London.

Andrew returned here later in July to scan two pieces from the Wernher Collection at Ranger’s House museum in Greenwich (see 3rd blog installment).  One piece is a prayer bead, and the other is a small boxwood coffin that is carved in a similar manner as the beads.  That should be fascinating… stay tuned.

July 9^th – Lisa and Sasha head back to Canada.  There’s nothing going on that’s relevant to the bead project – but Andrew did visit the Hunterian Museum.  This is an amazing collection of anatomical specimens – both human and animal, as well as the skeleton of Charles Byrne, the Irish Giant.  Fascinating stuff – lots here that could be microCT scanned! (Byrne’s skull has been scanned at the Natural History Museum).

 

Next time, Andrew visits the Nikon Metrology Centre-of-Excellence in Tring - where our microCT scanner was born - stay tuned to Part 3 of our blog series.

Tracking our Progress

One of the reasons that we love sharing and updating Sustainable Archaeology's progress on our blog is the opportunity to look back at how far we have come - literally from the ground up! In March of 2011, our Ancient Images Laboratory was just concrete, an idea of what could be. Now, in March of 2014, we have a fully outfitted and functioning space that features our micro-CT scanner, digital x-ray, artifact photography stations, and 3D printer.

A microCT and Archaeobotanical Analysis of Charcoal

The microCT scanner at Sustainable Archaeology was used to non-destructively study charcoal remains from the Arkona site, a ca. AD 1200 Younge Phase village site in Ontario. The scanned charcoal was analyzed and identified by Ontario archaeobotanist Rudy Fecteau. Using the microCT allowed for the charred remains to be digitally "split" in order to examine internal structures while preserving the original specimen for future analysis.

As noted in the video, the species of the second charcoal sample was not determined, and we invite our blog readers to assist us with the identification. Below are two closeup images giving a closer look at the internal structures of the second sample. If you have an idea of what the species might be, let us know by commenting on the blog, by tweeting the answer to us (@SustArchaeology), or by posting on our Facebook page.

 Special thank you to Rudy Fecteau for providing feedback and analysis on our scans, and for the delicious strawberry loaf!

Notes from the SA: February - March 2013

The February - March 2013 edition of Notes from the SA, Sustainable Archaeology's newsletter.

Guest Blog #4: A Non-Destructive Technology for Palaeopathology: Differential Diagnosis of Cranial Lesions in Archaeological Human Populations

Jennifer Morgan is a PhD candidate in the Department of Anthropology at Western University.  Jennifer has been working with Sustainable Archaeology's microCT scanner to scan and analyze Maya and Egyptian archaeological cranial samples exhibiting cribra orbitalia and/or porotic hyperostosis in order to assess whether the microCT is a more effective tool than destructive thin section techniques to study the etiology, activity, and healing of the lesions. 

This blog features Jennifer's contribution to the upcoming edition of the Sustainable Archaeology newsletter, Notes from the SA, which will be published on February 7th.

A Non-Destructive Technology for Palaeopathology: Differential Diagnosis of Cranial Lesions in Archaeological Human Populations

Jennifer Morgan, PhD Candidate, Western University 

Palaeopathology is defined as the scientific study of disease processes from archaeological human remains. The pattern of disease that affects a population is the expression of the biological and cultural stressors to which they were exposed. It is influenced by the environment, sex, social status, diet, occupation, and even cultural belief systems. These factors help researchers to interpret and explain the patterns of disease observable on human skeletal remains. Recent microscopic analyses of bone have revealed that porotic lesions of the skull, referred to as cribra orbitalia and porotic hyperostosis, can be caused by more than one health related condition. Originally associated with anaemia, other conditions including vitamin deficiencies and localized infections have also been implicated as possible causes of these lesions. Therefore, it is critical to establish methods that can accurately assess health conditions from skeletal remains. Inaccurate diagnoses can have significant implications for our current understandings of how disease and other health related conditions may have evolved over time, across geographic space, and how they may have affected human populations in the past.

The purpose of my current doctoral research is to examine an innovative non-destructive method for improving the accuracy of disease diagnosis in archaeological skeletal samples.  The principal objective of this study is to determine whether micro-computed tomography (μCT) and advanced methods of digital image analysis can be used in palaeopathology to visualize small scale bone changes which are typical of certain health conditions. The goals of this research are two-fold.  First, I wish to assess the capability of μCT and digital image analysis as sufficient alternatives to destructive thin section techniques which are traditionally used for microscopic skeletal analysis in bioarchaeological research. Second, I wish to evaluate the ability of µCT for more reliable differentiation between the various pathological conditions that contribute to the presence skeletal lesions in archaeological human remains.

Why is this significant?  In order to establish a reliable diagnosis it is often necessary to analyze the microscopic structures of diseased bone. Microscopy is essential in palaeopathology since although several disease processes can lead to similar bone surface changes, microscopic analyses demonstrate that there are patterns of microscopic changes which are unique to specific diseases. The classic way to examine bone microscopically is through the use of histological thin sections of bone, which require significant preparation and destruction of the sample. The method proposed for my doctoral research, using μCT, requires little to no sample preparation and is a method which has the potential for high resolution bone analysis, while eliminating the need for destructive sampling of valuable archaeological remains. 

For this research project, skeletal samples have been drawn from an Egyptian and several Maya collections housed at Western University in London, Ontario.  A large number of individuals with observable porotic cranial lesions have been μCT scanned in the Ancient Images Laboratory.  The resulting images are currently being qualitatively and quantitatively analyzed using the digital image analysis software VGStudio Max 2.2. These analyses of bone structural changes will determine whether the characteristic microscopic patterns indicative of anaemia, vitamin deficiencies, and infectious processes described in the literature can be differentiated using μCT. It is anticipated that the results of this research project will make a significant contribution to palaeopathology by providing non-destructive, high resolution digital techniques for the diagnosis of disease from archaeological skeletal samples as well as vastly improving our epidemiological understandings of health and disease in archaeological populations.

MicroCT Rotating Target and a Holiday Fruit Cake

In the Sustainable Archaeology Ancient Images Lab, we've been performing proof of concept tests using the rotating target on the microCT. The rotating target enables the user to "up" the flux (amount of power) that can be delivered to the target, without degrading the spot size - essentially allowing for faster scanning without compromising the excellent resolution of the machine. This give us the ability to greatly increase the amount of power we can use in a scan, allowing us to scan very dense objects, including meteorites, or, holiday fruit cake!

Special thank you to Hope Miles for providing the delicious fruit cake!

Yes the Cat: A Study of Mummification

The "Yes the Cat" project is an interdisciplinary investigation led by Dr. Andrew Nelson of the Department of Anthropology at Western University. The project is an ongoing study of the effects of mummification on different tissues of the body as demonstrated by the individual of interest - a domestic house cat named Yes.

Yes was mummified at the request of his owner, after dying of natural causes eight years ago. Since the time of the mummification, he has been studied using MR and clinical CT imaging in order to see beneath the exterior wrappings, to examine how the remains have changed over time.

Most recently, Yes the Cat was scanned using Sustainable Archaeology's microCT scanner. The microCT provides an additional means to non-destructively examine Yes the Cat's "afterlife", without removing any of the wrappings or disturbing the remains below. In the video below, Yes's skeleton was isolated from the layers of wrappings, which are digitally removed, allowing for the examination of the skeletal remains.

                                     

 

By isolating different densities, the researchers were also able to examine the condition of remaining internal organs, such as the heart, seen in red in the image below.

This cross-section, produced using the SA microCT's software, provides a more complete picture of Yes - through the wrappings down to the skeleton, also revealing what remains of the brain, heart and tongue.

Through digital imaging, Yes the Cat will continue to be a source of information about the effects of mummification for years to come, contributing broadly to our understanding of mummification and how mummified remains change over time. These findings can be applied to other cases of mummification, including both humans and other animals.

The Yes the Cat project will be presented at the upcoming Annual Meeting of the Canadian Association for Physical Anthropology at the University of Victoria in Victoria, B.C., on November 13th.