Search results for "FOS"
showing 10 items of 15075 documents
Last Millennium hydro-climate variability in Central–Eastern Europe (Northern Carpathians, Romania)
2015
Proxy-based reconstructions of climate variability over the last millennium provide important insights for understanding current climate change within a long-term context. Past hydrological changes are particularly difficult to reconstruct, yet rainfall patterns and variability are among the most critical environmental variables. Ombrotrophic bogs, entirely dependent on water from precipitation and sensitive to changes in the balance between precipitation and evapotranspiration, are highly suitable for such hydro-climate reconstructions. We present a multi-proxy analysis (testate amoebae, plant macrofossils, stable carbon isotopes in Sphagnum, pollen, spores and macroscopic charcoal) from …
2017
Ranking among the largest volcanic eruptions of the Common Era (CE), the ‘Millennium Eruption’ of Changbaishan produced a widely-dispersed tephra layer (known as the B-Tm ash), which represents an important tie point for palaeoenvironmental studies in East Asia. Hitherto, there has been no consensus on its age, with estimates spanning at least the tenth century CE. Here, we identify the cosmogenic radiocarbon signal of 775 CE in a subfossil larch engulfed and killed by pyroclastic currents emplaced during the initial rhyolitic phase of the explosive eruption. Combined with glaciochemical evidence from Greenland, this enables us to date the eruption to late 946 CE. This secure date rules out…
Climate controls on the Holocene development of a subarctic lake in northern Fennoscandia
2015
International audience; Climate exerts strong control over the functioning of northern freshwater ecosystems, yet their resilience and responses to climate forcing may vary. We examined postglacial development patterns in subarctic Lake Varddoaijavri to discern the impact of direct climate controls, catchment influence, and ontogenic processes on the ecological functioning of the lake over the Holocene. Subfossil diatom assemblages together with the elemental and stable isotopic (delta C-13, delta N-15) composition of sediment organic matter were used to examine climate-induced changes in the structure of the phototrophic community and transport of terrestrial organic matter from the catchm…
Des os dans les fossés et des animaux dans les enclos : diversité des fonctions et limites des interprétations
1999
Des animaux vivants ont pu sejourner de maniere temporaire ou permanente dans certaines des enceintes qui parsement la Gaule au deuxieme Âge du Fer. Mais ils ont pu egalement y etre mis mort, manges ou abandonnes a la decomposition. La diversite des fonctions qu'ont pu remplir les enclos vis-a-vis de l'elevage et de l'usage des animaux est grande. Notre propos est d'essayer de voir dans quelle mesure il est possible de les restituer, et quels indices peuvent nous aider dans cette demarche.
Cardinal invariants of cellular Lindelof spaces
2018
A space X is said to be cellular-Lindelof if for every cellular family $$\mathcal {U}$$ there is a Lindelof subspace L of X which meets every element of $$\mathcal {U}$$ . Cellular-Lindelof spaces generalize both Lindelof spaces and spaces with the countable chain condition. Solving questions of Xuan and Song, we prove that every cellular-Lindelof monotonically normal space is Lindelof and that every cellular-Lindelof space with a regular $$G_\delta $$ -diagonal has cardinality at most $$2^\mathfrak {c}$$ . We also prove that every normal cellular-Lindelof first-countable space has cardinality at most continuum under $$2^{<\mathfrak {c}}=\mathfrak {c}$$ and that every normal cellular-Lindel…
Pullneyocoris dentatus gen. et sp. nov. (Hemiptera: Pentatomoidea: Cydnidae), the third representative of the subfamily Amnestinae from mid-Cretaceou…
2020
Abstract A new genus and species of burrower bug, Pullneyocoris dentatus gen. et sp. nov. (Hemiptera: Cydnidae: Amnestinae), is described from amber of northern Myanmar. It is the third representative of this family known from Burmese amber, and besides its autapomorphies, it presents a mixture of characters relevant to the extant Parachilocoris Horvath, 1919 and Pullneya Horvath, 1919. A comparison of this new genus to the two genera already described from the burmite, i.e. Chilamnestocoris Lis J.A., Lis. B. & Heiss, 2018, and Punctacorona Wang, Du, Yao & Ren, 2019 is also provided.
Presence of Naraoia Walcott, 1912 in the middle Cambrian of Europe (Murero, NE Spain).
2018
Este artículo se encuentra disponible en la página web de la revista en la siguiente URL: http://sepaleontologia.es/revista/anteriores/SJP%20(2018)%20vol.%2033/vol.%201/04.pdf The genus Naraoia Walcott, 1912, a Burgess Shale-type fossil known from the lower and middle Cambrian of British Columbia (Canada), Idaho and Utah (USA), as well as from Yunnan and Guizhou provinces (China), is now reported from the middle Cambrian of Murero (Zaragoza, Spain), which is the first record in the Acadobaltic province. The only fragmented specimen found is determined as Naraoia sp., its age being Pardailhania multispinosa Zone (Drumian Stage). This new datum reinforces the hypothesis of the existence of a …
RTS2 - the Remote Telescope System
2010
RTS2 is an open source observatory manager. It was written from scratch in the C++ language, with portability and modularity in mind. Its driving requirements originated from quick follow-ups of Gamma Ray Bursts. After some years of development it is now used to carry tasks it was originally not intended to carry. This article presents the current development status of the RTS2 code. It focuses on describing strategies which worked as well as things which failed to deliver expected results. Copyright © 2010 Petr Kubánek.
Using machine learning to disentangle LHC signatures of Dark Matter candidates
2019
We study the prospects of characterising Dark Matter at colliders using Machine Learning (ML) techniques. We focus on the monojet and missing transverse energy (MET) channel and propose a set of benchmark models for the study: a typical WIMP Dark Matter candidate in the form of a SUSY neutralino, a pseudo-Goldstone impostor in the shape of an Axion-Like Particle, and a light Dark Matter impostor whose interactions are mediated by a heavy particle. All these benchmarks are tensioned against each other, and against the main SM background ($Z$+jets). Our analysis uses both the leading-order kinematic features as well as the information of an additional hard jet. We explore different representa…
The Role of Recent Admixture in Forming the Contemporary West Eurasian Genomic Landscape
2015
Summary Over the past few years, studies of DNA isolated from human fossils and archaeological remains have generated considerable novel insight into the history of our species. Several landmark papers have described the genomes of ancient humans across West Eurasia, demonstrating the presence of large-scale, dynamic population movements over the last 10,000 years, such that ancestry across present-day populations is likely to be a mixture of several ancient groups [1, 2, 3, 4, 5, 6, 7]. While these efforts are bringing the details of West Eurasian prehistory into increasing focus, studies aimed at understanding the processes behind the generation of the current West Eurasian genetic landsc…