Is the Mesolithic-Neolithic Subsistence Dichotomy Real? New Stable Isotope Evidence from the Danube Gorges

The article presents new results of stable isotope analyses made on animal and human bones from the Mesolithic-early Neolithic sites of Lepenski Vir and Vlasac in the Danube Gorges of the Balkans. It reconstructs the food web for the region during these periods on the basis of stable isotope analyses of mammal and fish species found at Vlasac. These results are compared to measurements made on human burials from the two sites. In the light of these new results, the article also discusses interpretations provided by previous isotopic studies of this material. It concludes that great care is required in the interpretation of stable isotope results due to inherent methodological complexities of this type of analysis, and suggests that it is also necessary to integrate stable isotope results with information based on the examination of faunal remains and the archaeological context of analysed burials when making inferences about palaeodietary patterns

Search for supernova-produced 60Fe in a marine sediment

An 60Fe peak in a deep-sea FeMn crust has been interpreted as due to the signature left by the ejecta of a supernova explosion close to the solar system 2.8 +/- 0.4 Myr ago [Knie et al., Phys. Rev. Lett. 93, 171103 (2004)]. To confirm this interpretation with better time resolution and obtain a more direct flux estimate, we measured 60Fe concentrations along a dated marine sediment. We find no 60Fe peak at the expected level from 1.7 to 3.2 Myr ago. However, applying the same chemistry used for the sediment, we confirm the 60Fe signal in the FeMn crust. The cause of the discrepancy is discussed.Comment: 15 pages, 5 figures, submitted to PR

Discovery Prospects for a Supernova Signature of Biogenic Origin

Approximately 2.8 Myr before the present our planet was subjected to the debris of a supernova explosion. The terrestrial proxy for this event was the discovery of live atoms of 60Fe in a deep-sea ferromanganese crust. The signature for this supernova event should also reside in magnetite Fe3O4 microfossils produced by magnetotactic bacteria extant at the time of the Earth-supernova interaction, provided the bacteria preferentially uptake iron from fine-grained iron oxides and ferric hydroxides. Using estimates for the terrestrial supernova 60Fe flux, combined with our empirically derived microfossil concentrations in a deep-sea drill core, we deduce a conservative estimate of the ^{60}{Fe} fraction as 60Fe/Fe ~ 3.6 x 10^{-15}. This value sits comfortably within the sensitivity limit of present accelerator mass spectrometry capabilities. The implication is that a biogenic signature of this cosmic event is detectable in the Earth's fossil record.Comment: As it appears in Icaru

An IRT Analysis of Motive Questionnaires: The Unified Motive Scales

Multiple inventories claiming to assess the same explicit motive (achievement, power, or affiliation) show only mediocre convergent validity. In three studies (N = 1685) the structure, nomological net, and content coverage of multiple existing motive scales was investigated with exploratory factor analyses. The analyses revealed four approach factors (achievement, power, affiliation, and intimacy) and a general avoidance factor with a facet structure. New scales (the Unified Motive Scales; UMS) were developed using IRT, reflecting these underlying dimensions. In comparison to existing questionnaires, the UMS have the highest measurement precision and provide short (6-item) and ultra-short (3-item) scales. In a fourth study (N = 96), the UMS demonstrated incremental validity over existing motive scales with respect to several outcome criteria

Skill needs and continuing vocational training in Sweden

The main purpose of this paper is to explore whether and how the amount of firmsponsored Continuing Vocational Training (CVT) provided in Sweden from 1999 onwards was influenced by institutional conditions. The Swedish labour market is characterised by a relatively large amount of publicly subsidised CVT. How this affects the incidence of firm-sponsored CVT ultimately depends on whether publicly financed training is a substitute for, a complement to or is independent from company training. Recent Swedish research and descriptive data suggest that elements of all three cases exist. If the two were complements, the phenomenon of underinvestment in CVT which is frequently considered to exist would be attenuated by the provision of publicly financed CVT. Support for this view hinges on the notion that public CVT evens out human capital accumulation within the labour force, that this in turn contributes to a compressed wage structure and that compressed wages have a positive influence on the provision of firm-sponsored CVT. -- Anliegen des vorliegenden Papiers ist die Untersuchung des Einflusses von institutionellen Faktoren auf die Häufigkeit betrieblicher Weiterbildung in Schweden. Hierbei wird der Zeitraum ab dem Jahr 1999 betrachtet. Der Arbeitsmarkt in Schweden ist durch ein relativ hohes Niveau öffentlicher Subventionen in berufliche Weiterbildung geprägt. Der Zusammenhang zwischen einem hohen Niveau öffentlich geförderter beruflicher Weiterbildung und betrieblicher Weiterbildung hängt davon ab, ob die beiden Finanzierungsformen substitutiv, komplementär oder unabhängig voneinander sind. Aktuelle Forschungsergebnisse deuten darauf hin, dass Elemente aller drei Wirkmechanismen existieren. Bei Komplementarität kann der oft beschriebenen Unterinvestition in betriebliche Weiterbildung begegnet werden, indem öffentlich geförderte berufliche Weiterbildung die Unterschiede in der Verteilung des Humankapitals in der Erwerbsbevölkerung ausgleicht. Dieses wiederum würde zu einer Verringerung der Lohnspreizung führen, welche dann einen positiven Einfluss auf betrieblich finanzierte Weiterbildung ausübt.

Late Pleistocene human genome suggests a local origin for the first farmers of central Anatolia

Anatolia was home to some of the earliest farming communities. It has been long debated whether a migration of farming groups introduced agriculture to central Anatolia. Here, we report the first genome-wide data from a 15,000-year-old Anatolian hunter-gatherer and from seven Anatolian and Levantine early farmers. We find high genetic continuity (~80–90%) between the hunter-gatherers and early farmers of Anatolia and detect two distinct incoming ancestries: an early Iranian/Caucasus related one and a later one linked to the ancient Levant. Finally, we observe a genetic link between southern Europe and the Near East predating 15,000 years ago. Our results suggest a limited role of human migration in the emergence of agriculture in central Anatolia

Edge switching transformations of quantum graphs

Discussed here are the effects of basics graph transformations on the spectra of associated quantum graphs. In particular it is shown that under an edge switch the spectrum of the transformed Schr\"odinger operator is interlaced with that of the original one. By implication, under edge swap the spectra before and after the transformation, denoted by $\{ E_n\}_{n=1}^{\infty}$ and $\{\widetilde E_n\}_{n=1}^{\infty}$ correspondingly, are level-2 interlaced, so that $E_{n-2}\le \widetilde E_n\le E_{n+2}$. The proofs are guided by considerations of the quantum graphs' discrete analogs