/customers/academia.dk/academia.dk/httpd.www/Blog/wp-content/plugins/wp-cache/wp-cache-phase1.php Tænketanken | En blog om sundhedsvæsen, medicinhistorie, neurovidenskab og hverdagen i et klinisk biokemisk laboratorium - Part 2

Four methods of trepanation demonstrated on a single human skull [en]

29. september 2013

Dr. Thomas Wilson Parry (1866-1945) owned this particular skull, which he used to perform practical research on trepanation. He performed roughly 50 trepanation experiments on the skulls of the more and less recent deceased, using in this case a shark’s tooth, a flint-pointed bow drill, a flint scraper, and obsidian to achieve the variety of holes. Parry published Trephination of the Living Human Skull in Prehistoric Times in 1923, and an amusing ballad about the practice in 1918.

Read more here.

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DINO 101: Some articles on the use of stable isotopes in dino research [da]

9. september 2013

  • Shaena Montanari, Pennilyn Higgins, Mark A. Norell (2013). Dinosaur eggshell and tooth enamel geochemistry as an indicator of Mongolian Late Cretaceous paleoenvironments. Palaeogeography, Palaeoclimatology, Palaeoecology 370 158-166. http://www.sciencedirect.com/science/article/pii/S0031018212006736 [pdf]
  • Romain Amiot, Christophe Lécuyer, Eric Buffetaut, Gilles Escarguel, Frédéric Fluteau, François Martineau. (2006). Oxygen isotopes from biogenic apatites suggest widespread endothermy in Cretaceous dinosaurs. Earth and Planetary Science Letters 246 41–54 http://www.sciencedirect.com/science/article/pii/S0012821X06003050 [pdf]
  • Kathryn J. Stanton Thomas, Sandra J. Carlson. (2004). Microscale d18O and d13C isotopic analysis of an ontogenetic series of the hadrosaurid dinosaur Edmontosaurus: implications for physiology and ecology. Palaeogeography, Palaeoclimatology, Palaeoecology 206 257– 287 http://www.sciencedirect.com/science/article/pii/S0031018204000161 [pdf]
  • Robert A. Eagle, Thomas Tütken, Taylor S. Martin, Aradhna K. Tripati2,, Henry C. Fricke, Melissa Connely, Richard L. Cifelli, John M. Eiler. 2011. Dinosaur Body Temperatures Determined from Isotopic (13C-18O) Ordering in Fossil Biominerals. Science. Vol. 333 no. 6041 pp. 443-445 http://www.sciencemag.org/content/333/6041/443.abstract [pdf]

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[da]

6. september 2013

Computed tomography in paleoanthropology — an overview

by Heike Scherf

"Computed tomography (CT) was first applied in the early 1970s and introduced subsequently a new perspective towards anatomical imaging. In the last decade, high-resolution CT (HR-CT) had a high impact on anthropology and paleoanthropology through its ability to define and explore subtle differences in hard tissue structures in fossil and extant humans and nonhuman primates. CT is very suitable for unique fossil material, because it is destruction free and the original material stays intact while the internal structures are digitized. The imaging yields a virtual copy of the object, which can be used for the generation of detailed copies of original fossil material. CT data allow multiple studies in parallel and independently on specimens which are not commonly accessible. Diverse CT systems with different performance characteristics as designed for different functions can make it difficult for a researcher to choose the most appropriate CT system and to check the image quality of CT scans. The physical principles involved in CT imaging and the principles of signal processing and computer graphics can help to choose the best scan setting and the most suitable CT system for a study. Quantitative and qualitative analysis can also be improved and comparisons between different studies can be facilitated when the above mentioned principles are taken into account. In the following, I will give an overview of the different CT systems and discus both theoretical and practical matters of CT imaging using the example of trabecular bone" (read more/not open access).

Source: Archaeological and Anthropological Sciences 2013, doi: 10.1007/s12520-013-0128-5; top image: Max Planck Institute

Via theolduvaigorge

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My favorite drink [en]

14. august 2013

Drink Coffee! Do Stupid Things Faster with More Energy.

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The Graves of a Catholic woman and her Protestant husband, Holland [da]

30. juni 2013

Graves of a Catholic woman and her Protestant husband, who were not allowed to be buried together.

Via @Earth_Pics

I wondered where to find these peculiar graves, and what the history behind them were. I now see that dichotomization can add at least some of the story:

In the Protestant part of this cemetery, J.W.C van Gorcum, colonel of the Dutch Cavalry and militia commissioner in Limburg, is buried. His wife, lady J.C.P.H van Aefferden, is buried in the Catholic part. They were married in 1842, the lady was 22 and the colonel was 33, but he was a protestant and didn’t belong to the nobility. This caused quite a commotion in Roermond. After being married for 38 years, the colonel died in 1880 and was buried in the protestant part of the cemetery against the wall. His wife died in 1888 and had decided not to be buried in the family tomb but on the other side of the wall, which was the closest she could get to her husband. Two clasped hands connect the graves across the wall.

Roermond is in Holland, and you can actually find the grave on Google Maps! Plus som extra photos of the grave, incl. pic no. 2 of the grave dressed in snow.

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Alice and Augustus Le Plongeon camping in Governor’s Palace at Uxmal (1876) [da]

29. juni 2013

Alice and Augustus Le Plongeon camped in the center room of the Governor’s Palace at Uxmal during their field work there in 1876

Alice Dixon Le Plongeon (1851–1910) was an English photographer, amateur archaeologist traveller, and author. Together with her husband Augustus Le Plongeon (1825–1908) she spent eleven years living and working in southern Mexico and Central America photographing and studying the ruined cities of the pre-Columbian Maya civilization. Together with her husband, she helped make some of the first photographs of ruins at Chichén Itzá and Uxmal.

Alice and Augustus camped in the center room of the Governor’s Palace at Uxmal during their field work there in 1876. Note their surveying and photographic equipment, Alice’s Remington Rolling Block rifle, hammock, and their dog Trinity sleeping in the corner. Not in the photo is their portable darkroom where they developed their photos. Photo by Alice and Augustus, 1876

Source: Exavation Of The Platform Of Venus, Chichén Itzá, Yucatán, México: The Pioneering Field Work of Alice Dixon Le Plongeon and Augustus Le Plongeon.

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The periodic table as a spiral [da]

6. juni 2013

Another fascinating alternative version of the Periodic Table!

In May 1949, LIFE Magazine published a stunning series of images to accompany an issue dedicated largely to The Atom. You can check out the feature in its entirety here, but the reimagination of the periodic table of elements as a colorful spiral is easily one of the most striking graphics of the lot. [Click here to see it in hi-res]

The periodic table as a spiral
The periodic table as a spiral

Here in its entirety is the caption that accompanied the original graphic:

    The irregular spiral above is a systematic arrangement of the 92 natural elements, the four new elements so far created by man and eight more elements which is theoretically possible to create. It is called the periodic table of the elements. The sequence begins with hydrogen (at the center of the spiral), which is the first and simplest element. Under its name appears its chemical symbol (left), its atomic weight (right) and a larger numeral which gives the total number of electrons in its atom. It is on the basis of this number that the elements are arranged in sequence: after hydrogen, with its single electron, come helium with two, lithium with three, beryllium with four and so on around the spiral.

    The colors and construction of the table express another kind of relationship among the elements: the repetition, at regular intervals, of the chemical properties of the first few. Characteristics are thus repeated periodically in the progression form the simplest to the most complex. The table is so organized that elements whose chemistry is almost identical are grouped together in blocks of connected by solid arrows (all the inert gases–helium, neon, etc.–fall in the single gray block at the left). Broken arrows relate groups of elements which are similar in most respects but differ in a few of their properties. All related elements are given different shades of the same color. The key to this similarity among elements is found in the arrangement rather than the number of the electrons in their atoms. Only the electrons in the outer shell affect an atom's chemical nature. Therefore all elements whose atoms have identical outer shells are chemically related, regardless of the total umber of electrons which each of them may possess. For example, lithium, sodium and the other elements in the red segment at left all have one electron in their outer shells and are therefore similar though they differ in the total number of their electrons. Each complete circuit of the table starts with one of these elements and ends with an element in the adjacent gray segment whose atom's outer shell is complete.

    This table, like all attempts to reduce the basic phenomena of nature to a simple pattern, falls somewhat short of its objective. For one thing, there are variations in the sequence of elements which do not fit readily into its graphic form. For another, it is not so much a simplification as an orderly presentation which specifies the relationship between elements but leaves much about them to be explained... Yet in expressing this relationship the table reveals the extraordinary symmetry and order which underlie the universe.

Check out my earlier posts on the periodic table:


Added June 7th 2013: Just found a wonderful post on alternative periodic tables at chemistry-blog.com


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The etymology of the fibula [da]

26. maj 2013

Etymology of the Fibula

A nice little drawing by Shaza Ali explaining the etymology of the fibula.

“Fibula” is the Latin word meaning “clasp” or brooch. Modern safety pins evolved from the ancient fibula brooch. The leg bone fibula is named so because of its resemblance to the safety pin.

Pencil & white charcoal. October 2012.

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A canary in a coal mine [da]

25. maj 2013
In Memory of Little Joe. Died November 3rd 1875. Aged 3 Years
A canary in a coal mine Another canary in a coal mine

In the 19th century and well into the 20th century coal miners would traditionally take canaries in cages down into the mine with them. The birds would act as an early warning system for carbon monoxide gas. When the canary stopped singing the miner would know that he had to escape the chamber he was in.

This particular yellow canary on the top photo was obviously a favoured pet as well as a working bird. Inscribed with the legend : ‘In Memory of Little Joe. Died November 3rd 1875. Aged 3 Years’

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The Porsmose Man: A Neolithic skeleton from Denmark [da]

25. maj 2013
The skull of the Porsmose Man
The sternum The location of Porsmose

Image 1: The bone arrowhead still sat in the skull, when the skeleton of a 35-40-year-old man man was found in 1946 in the peat bog Porsmose, near Næstved. Another arrow was also deeply embedded in the man’s breastbone. Both arrows must have been fired at an angle from above and from close distance. This suggests that the man was surprised by his attackers or perhaps was the victim of an execution. After this the body was thrown out into what was then a lake. The arrows are a type which belong to the Single Grave Culture period.

Image 2: The Porsmose man’s breastbone (sternum) was perforated by a bone arrow.

Image 3: The Porsmose skeleton was found in a bog north-east of Holme Olstrup near Næstved.

The skull is on display at the National Museum of Denmark in Copenhagen

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