Iridium Across the Triassic-Jurassic Boundary in Austria

Distribution of iridium and associated geochemistry across the Triassic–Jurassic boundary in sections at Kuhjoch and Kendlbach, Northern Calcareous Alps, Austria

Authors:

Tanner et al

Abstract:

Samples from strata spanning the Triassic–Jurassic boundary at the GSSP at Kuhjoch and at Kendlbachgraben were studied by NAA, XRF and combustion analysis to determine Ir levels and associated geochemistry. The results are compared to previously determined carbon isotope stratigraphy at these sections. Ir concentrations in the limestones of the Kössen Formation at Kuhjoch are very low (< 10 pg/g) below the top of the formation, rising to 26 pg/g, in the T-bed at the top of the Eiberg Member. The Tiefengraben Member of the Kendlbach Formation exhibits higher concentrations of Ir in general relative to the strata below. The shift to higher levels is abrupt at the base of the member, coinciding with a decrease in carbonate content. Concentrations of 60 to 80 pg/g are typical through the entire thickness of the Schattwald Beds and into the gray Tiefengraben Member strata, peaking at 145 pg/g. Concentrations decline to 30–40 pg/g above 680 cm from the formation base, coinciding with increasing carbonate content. The analyses from the Kendlbachgraben section compare well with those from Kuhjoch, with similar difference in Ir concentration between the Kössen and Kendlbach formations. In both sections, the initial increase in Ir corresponds to the initial carbon isotope excursion. Concentrations of redox-sensitive elements indicate transient reducing conditions during deposition of the uppermost Kössen Formation, but oxidizing conditions during Tiefengraben Member deposition. The Al/Ti ratio indicates more intense weathering during deposition of the lowermost 20 cm of the Tiefengraben Member, but otherwise consistently humid to sub-humid climate prevailed during deposition. The primary control on Ir concentration in the sampled section is formation lithology, although there are variations within the Tiefengraben Member that are independent of carbonate content. Enrichment of Ir at the top of the T-bed is associated with a redox boundary, but the cause of other variations is undetermined.

This can Only end Well: Three new Cyborgs With Austrian Accents

Three Austrian men have become the first in the world to undergo a new technique called "bionic reconstruction", enabling them to use a robotic prosthetic hand controlled by their mind, according to new research published in The Lancet. All three men suffered for many years with brachial plexus injuries [1] and poor hand function as a result of motor vehicle and climbing accidents.

The new technique was developed by Professor Oskar Aszmann, Director of the Christian Doppler Laboratory for Restoration of Extremity Function at the Medical University of Vienna, together with engineers from the Department of Neurorehabilitation Engineering of the University Medical Center Goettingen. It combines selective nerve and muscle transfers, elective amputation, and replacement with an advanced robotic prosthesis (using sensors that respond to electrical impulses in the muscles). Following comprehensive rehabilitation, the technique restored a high level of function, in all three recipients, aiding in activities of daily living.

"In effect, brachial plexus avulsion injuries represent an inner amputation, irreversibly separating the hand from neural control. Existing surgical techniques for such injuries are crude and ineffective and result in poor hand function", explains Professor Aszmann. "The scientific advance here was that we were able to create and extract new neural signals via nerve transfers amplified by muscle transplantation. These signals were then decoded and translated into solid mechatronic hand function" [2]

Before amputation, all three patients spent an average of 9 months undergoing cognitive training, firstly to activate the muscles, and then to use the electrical signals to control a virtual hand. Once they had mastered the virtual environment, they practiced using a hybrid hand--a prosthetic hand attached to a splint-like device fixed to their non-functioning hand (Figure 1 page 3 and video).

Three months after amputation, robotic prostheses gave all three recipients substantially better functional movement in their hands, improved quality of life, and less pain. For the first time since their accidents all three men were able to accomplish various everyday tasks such as picking up a ball, pouring water from a jug, using a key, cutting food with a knife, or using two hands to undo buttons.

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First Glimpse at Lower Jurassic Benthic Paleodiversity

First glimpse into Lower Jurassic deep-sea biodiversity: in situ diversification and resilience against extinction

Authors:

Thuy et al

Abstract:

Owing to the assumed lack of deep-sea macrofossils older than the Late Cretaceous, very little is known about the geological history of deep-sea communities, and most inference-based hypotheses argue for repeated recolonizations of the deep sea from shelf habitats following major palaeoceanographic perturbations. We present a fossil deep-sea assemblage of echinoderms, gastropods, brachiopods and ostracods, from the Early Jurassic of the Glasenbach Gorge, Austria, which includes the oldest known representatives of a number of extant deep-sea groups, and thus implies that in situ diversification, in contrast to immigration from shelf habitats, played a much greater role in shaping modern deep-sea biodiversity than previously thought. A comparison with coeval shelf assemblages reveals that, at least in some of the analysed groups, significantly more extant families/superfamilies have endured in the deep sea since the Early Jurassic than in the shelf seas, which suggests that deep-sea biota are more resilient against extinction than shallow-water ones. In addition, a number of extant deep-sea families/superfamilies found in the Glasenbach assemblage lack post-Jurassic shelf occurrences, implying that if there was a complete extinction of the deep-sea fauna followed by replacement from the shelf, it must have happened before the Late Jurassic.

Astounding

Taking old World War II photos, Russian photographer Sergey Larenkov carefully photoshops them over more recent shots to make the past come alive. Not only do we get to experience places like Berlin, Prague, and Vienna in ways we could have never imagined, more importantly, we are able to appreciate our shared history in a whole new and unbelievably meaningful way.

Words fail me. This is just astounding.