Nature of Reduced Carbon in Martian Meteorites

Martian meteorites provide important information on the nature of reduced carbon components present on Mars throughout its history. The first in situ analyses for carbon on the surface of Mars by the Viking landers yielded disappointing results. With the recognition of Martian meteorites on Earth, investigations have shown carbon-bearing phases exist on Mars. Studies have yielded presence of reduced carbon, carbonates and inferred graphitic carbon phases. Samples ranging in age from the first approximately 4 Ga of Mars history [e.g. ALH84001] to nakhlites with a crystallization age of 1.3 Ga [e.g. Nakhla] with aqueous alteration processes occurring 0.5-0.7 Ga after crystallizaton. Shergottites demonstrate formation ages around 165-500 Ma with younger aqueous alterations events. Only a limited number of the Martian meteorites do not show evidence of significance terrestrial alterations. Selected areas within ALH84001, Nakhla, Yamato 000593 and possibly Tissint are suitable for study of their indigenous reduced carbon bearing phases. Nakhla possesses discrete, well-defined carbonaceous phases present within iddingsite alteration zones. Based upon both isotopic measurements and analysis of Nakhla's organic phases the presence of pre-terrestrial organics is now recognized. The reduced carbon-bearing phases appear to have been deposited during preterrestrial aqueous alteration events that produced clays. In addition, the microcrystalline layers of Nakhla's iddingsite have discrete units of salt crystals suggestive of evaporation processes. While we can only speculate on the origin of these unique carbonaceous structures, we note that the significance of such observations is that it may allow us to understand the role of Martian carbon as seen in the Martian meteorites with obvious implications for astrobiology and the pre-biotic evolution of Mars. In any case, our observations strongly suggest that reduced organic carbon exists as micrometer- size, discrete structures on Mars associated with clay and salt minerals. The Mars Science Laboratory s investigators should be aware of reduced organic carbon components within clay-bearing phases

The Case against Mercury as the Angrite Parent Body (APB)

Angrites are not plausibly from Mercury based on their high FeO contents and ancient ages (e.g., [1]). Rather, the early crystallization ages of angrites argues for a small asteroidal-sized parent body for these meteorites (e.g., [2]). Despite this, recently it has been proposed that Mercury is the APB [3, 4, 5, 6]. Preserved corona and symplectite textures and the presence of 120 triple junctions in NWA 2999 have been cited as requiring a planetary origin [3, 4], with the symplectites in NWA 2999 resulting from rapid decompression during uplift via thrust faults on Mercury [4], and the coronas during subsequent cooling at low pressure. Glasses along grain boundaries and exsolution lamellae possibly indicative of rapid melting and cooling in NWA 4950 are cited as evidence of rapid decompression [6]. To explain the discrepancy between spectral observations of the Mercurian surface and the high FeO contents in angrites, an early (~4.5 Ga), collisionally-stripped FeO-rich basaltic surface has been suggested for Mercury [5, 6]

Riddling traditions in eastern Indonesia and East Timor: some preliminary notes

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Risk assessment and comparison of short-term and long-term emissions for different treatment and disposal phases of MSW

International audienceA research program including a comparison between short term and long term emissions of MSW landfill started in 2006. The goal of that program was to access the human health chronic risk of three different waste disposal processes (anaerobic with/without leachate recirculation, with/without aerobic pretreatment) and to provide new criteria for the disposal site. A methodological approach using both calibration of the short term fluxes by in situ measurements and the prediction of long term fluxes by the use of exponential decreasing functions was explored. The identification of contaminant species was made by qualitative and quantitative concentration measurements done in a first stage on the landfill gas, and the collection of chemical leachate load measurements. At this stage of the study, the work did not show specific chemical contaminant species for the different waste disposal

Zum Vorkommen und zur Erfassung der Wildkatze ("Felis silvestris", Schreber 1777) im Egge-Weser-Gebiet

Aus verschiedenen Regionen Deutschlands wird in den letzten Jahren gemeldet, dass sich die seltene und heimliche Wildkatze ausgehend von ihren letzten Rückzugsräumen wieder ausbreitet und verloren gegangenes Terrain zurückgewinnt. Auch im Kreis Höxter gibt es aus den letzten Jahren glaubwürdige Meldungen von Wildkatzen. Aufgrund ihrer heimlichen Lebensweise ist es durchaus möglich, dass diese Art auch im Raum zwischen Egge und Weser schon weiter verbreitet ist, als der bisherige Kenntnisstand es vermuten ließe, denn der Kreis Höxter liegt nahe an zwei großen Vorkommen dieser Art, dem Solling und dem Reinhardswald. Diese Vorkommen wiederum sind vernetzt mit Beständen im Kaufungerwald und möglicherweise in geringerem Maße mit der Harzpopulation (siehe Abb. 2). Die günstige Situation lässt hoffen, dass die Wildkatze über kurz oder lang wieder stabile Populationen in den größeren Waldbeständen des Kreises aufbauen wird. Besondere Planungsrelevanz erhält die Wildkatze dadurch, dass sie in der bundesweiten Roten Liste als stark gefährdet eingestuft wird, in Nordrhein-Westfalen gilt sie sogar als „vom Aussterben bedroht“ (FELDMANN, HUTTERER & VIERHAUS 1999). Weiterhin ist sie rechtlich geschützt durch die FFH-Richtlinie (Anhang IV), die Bundesartenschutzverordnung (besonders und streng geschützte Art, CITES (Washingtoner Artenschutzabkommen: Anhang II) und die Berner Konvention (Hessisches Ministerium für Umwelt, ländlichen Raum und Verbraucherschutz 2004). Im Naturschutz wird sie als Leitart für unzerschnittene und waldreiche Landschaften angesehen und vertritt damit auch andere große Säugetierarten mit großen Raumansprüchen wie z. B. den Rothirsch (SIMON & RAIMER 2007). Deswegen erscheint es über das naturkundliche Interesse hinaus sinnvoll, die aktuelle Situation der Wildkatze in diesem Raum einmal näher zu untersuchen. Der folgende Text soll interessierten Personen einen Einblick in das Leben der Wildkatze geben und darüber hinaus über eine praktikable Methode der Bestandserfassung informieren

Cognitive Innovation, Irony and Collaboration

What seems clear from the experiences of researchers in CogNovo is that the concept of cognitive innovation offered a new vocabulary, and thus a clear space, within which creativity could be explored free from the baggage of prior conflicting definitions. The concept was, from its inception, intrinsically ironic in the sense that Rich⁠ard Rorty developed the term. Although initially we did not fully appreciate the potential this offered, approaching creativity under the rubric of cognitive innova⁠tion led to novel ideas that would not have emerged if we had taken a more con⁠ven⁠tional discipline-led approach. One example was expressing creativity as a mathematical function and as a media form in a parallel text. The absurdity of describing a process of such complexity in this form did not pass us by. However, this self-conscious irony, not a common rhetorical strategy in the sciences, clarified our understanding of cognitive innovation as a recursive function that allowed us to express a continuity between the basic life processes of exploration, innovation and the construction of the self, and the social and cultural ramifications of these processes; creativity. It led us to conclude that cognitive innovation furnishes a view of the self as a dynamic entity, for whom reality and novelty are contingent on one’s current state, both of which can change and be changed, and offers a means for enhancing the rigor of the current debate on what counts as creative. It also reveals the value of irony in not disavowing the inevitability of multiple perspectives and prospectives on reality, and consequently offers a way to avoid unnecessary reductivism. In this paper, we will argue, as we take the insights of CogNovo forward, that irony offers a hitherto unappreciated strategy for collaborative research

Always returning: feedback and sensory processing in visual cortex and thalamus

[Abstract] Feedback projections are an integral part of the mammalian visual system. Although it is tempting to relegate them to a subsidiary role in visual processing, because their supposed latency and lag might appear to be unfavourable for an involvement in fast processing, this is a dangerous simplification. Certainly for the world in motion, feedback from higher motion areas can influence the transfer of ascending input when, or even before, the input arrives. Here, we consider the circuit formed by layer 6 feedback cells in the visual cortex and how this straddles the retinothalamic and thalamocortical transfer of visual input. We discuss its links to feedback from the cortical motion area MT (V5), and suggest that motion perception involves a dynamic interplay between MT, V1 and the thalamus. This review is part of the TINS special issue on The Neural Substrates of Cognition

Some Interrelations among Martial Arts, Personality Development, and Military Career

In my study, I attempt to present a diverse set of requirements through which a valuable person may be characterized for a professional army in the long term, with the use of a scientific description of the concept of human talent. In the second half of the article, I explain in detail the personality-, character- and ability-shaping effects of martial arts. Following the psychosocial development process introduced by Erikson I analyse the specific life-course model provided by Japanese martial arts, which focuses on the lifelong exercise of budō