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Wednesday, October 22, 2008

Dr. Jerald Block is a psychiatrist based in Portland, Oregon, United States. Dr. Block has attracted some media attention due to one theory of his – the idea that Internet addiction can be viewed as a distinct mental condition.

In an interview with Wikinews, Dr. Block discusses this theory, including what needs to be done about it, and the alleged violent response that can arise from an addict’s withdrawal. Below is the full exclusive interview.

Sunday, June 28, 2020

Last month, a study conducted by archæologist Dr. Naomi Martisius and other researchers concluded Neanderthals living in Europe tens of thousands of years ago were more sophisticated than previously thought. The now-extinct species used to carefully select bones from a particular animal species to manufacture their bone tools, the research showed. The research was published on May 8 in Nature’s Scientific Reports journal.

Dr Martisius and her team used five bone tools discovered from Neanderthals’ sites in southwest France for this research. Four of these bone tools were found in a site called Abri Peyrony and the other one was from Pech-de-l’Azé I. These tools were just a few centimetres in size and were about 50 thousand years old, Dr Martisius told Wikinews. Microscopy analysis of these bone tools called lissoirs (smoothers) suggested Neanderthals used these tools for working animal skin to leathers.

The study stated the fauna of the sites were primarily medium-sized ungulates such as reindeer, in one layer nearly 90%. Despite the overabundance of medium-sized ungulates, Neanderthals used ribs of large bovids for making lissoirs. Dr Martisius told Wikinews this was likely due to the physical characteristics of the bovid ribs, which were “thicker” and “stronger” as compared to the “thin and flimsy ribs” of reindeers. In order to check the origins of the bone tools, the researchers used a technology called non-destructive Zooarchæology by Mass Spectrometry (ZooMS).

Instead of damaging the bone artefacts in order to discover its origins, the researchers collected collagen from the plastic containers in which these artefacts were kept. Collagen is a type of protein. These bone artefacts were kept in plastic containers: some were kept for about five years, some for just a few months. During this time, the collagen proteins from bone tools were stuck to the walls of its plastic containers. The collagen samples collected from the walls of the containers are broken into smaller molecules called peptides by using a chemical enzyme called trypsin.

After the trypsin has broken collagen fibres into peptides, it is analysed using a technology called Matrix-assisted laser desorption/ionization (MALDI) Time-of-Flight mass spectrometer (ToF MS). The assisting matrix is a coloured compound. The acidic peptide is combined with the matrix, vapourised, and peptides are released. Some of them are positively-charged particles which travel across a vacuum tube in an electric field. Depending on the weight of the peptides, these molecules reach the end of the vacuum tube at different instances of time, forming a spectrum. These graphs are like unique fingerprints of a species: they are different for different species of animals. Looking at the database of such graphs, taxonomic identifications of the collagen proteins came be made.

All four bone tools from Abri Peyrony gave positive results and showed that the bones were made from large bovids, even though reindeer were more abundant during that time. One of the advantages of using bovid ribs over reindeer’s thin ribs was the bovid ribs would be more resistant to breaking during flexion, Dr Martisius said.

Dr Martisius said such non-destructive ZooMS analysis was previously conducted, but for tools no older than a few centuries. She said such an analysis had never been previously conducted for artefacts so ancient.

Wikinews caught up with Dr Martisius to discuss this research in-depth.