Search results for "Sphere"
showing 10 items of 2121 documents
Occurrence of whale barnacles in Nerja Cave (Málaga, southern Spain): Indirect evidence of whale consumption by humans in the Upper Magdalenian
2014
A total of 167 plates of two whale barnacle species (Tubicinella major Lamarck, 1802 and Cetopirus complanatus Morch, 1853) have been found in the Upper Magdalenian layers of Nerja Cave, Mina Chamber (Maro, Malaga, southern Spain). This is the first occurrence of these species in a prehistoric site. Both species are specific to the southern right whale Eubalena australis, today endemic in the Southern Hemisphere. Because of Antarctic sea-ice expansion during the Last Glacial Period, these whales could have migrated to the Northern Hemisphere, and reached southern Spain. Whale barnacles indicate that maritime-oriented forager human groups found stranded whales on the coast and, because of th…
Temari Balls, Spheres, SphereHarmonic: From Japanese Folkcraft to Music
2022
Temari balls are traditional Japanese toys and artworks. The variety of their geometries and tessellations can be investigated formally and computationally with the means of combinatorics. As a further step, we also propose a musical application of the core idea of Temari balls. In fact, inspired by the classical idea of music of spheres and by the CubeHarmonic, a musical application of the Rubik’s cube, we present the concept of a new musical instrument, the SphereHarmonic. The mathematical (and musical) description of Temari balls lies in the wide background of interactions between art and combinatorics. Concerning the methods, we present the tools of permutations and tessellations we ado…
G-CLASS: geosynchronous radar for water cycle science – orbit selection and system design
2019
The mission geosynchronous – continental land atmosphere sensing system (G-CLASS) is designed to study thediurnal water cycle, using geosynchronous radar. Although the water cycle is vital to human society, processes on timescalesless than a day are very poorly observed from space. G-CLASS, using C-band geosynchronous radar, could transform this. Itsscience objectives address intense storms and high resolution weather prediction, and significant diurnal processes such assnow melt and soil moisture change, with societal impacts including agriculture, water resource management, flooding, andlandslides. Secondary objectives relate to ground motion observations for earthquake, volcano, and subs…
Microbial succession of nitrate-reducing bacteria in the rhizosphere of Poa alpina across a glacier foreland in the Central Alps
2006
International audience; Changes in community structure and activity of the dissimilatory nitrate-reducing community were investigated across a glacier foreland in the Central Alps to gain insight into the successional pattern of this functional group and the driving environmental factors. Bulk soil and rhizosphere soil of Poa alpina was sampled in five replicates in August during the flowering stage and in September after the first snowfalls along a gradient from 25 to 129 years after deglaciation and at a reference site outside the glacier foreland (> 2000 years deglaciated). In a laboratory-based assay, nitrate reductase activity was determined colorimetrically after 24 h of anaerobic inc…
Statistical upscaling of ecosystem CO2 fluxes across the terrestrial tundra and boreal domain: Regional patterns and uncertainties
2021
The regional variability in tundra and boreal carbon dioxide (CO2) fluxes can be high, complicating efforts to quantify sink-source patterns across the entire region. Statistical models are increasingly used to predict (i.e., upscale) CO2 fluxes across large spatial domains, but the reliability of different modeling techniques, each with different specifications and assumptions, has not been assessed in detail. Here, we compile eddy covariance and chamber measurements of annual and growing season CO2 fluxes of gross primary productivity (GPP), ecosystem respiration (ER), and net ecosystem exchange (NEE) during 1990–2015 from 148 terrestrial high-latitude (i.e., tundra and boreal) sites to a…
A Sociohistorical View of Cultural Policies
2007
There is a need to articulate the theoretical basis for the historical orientation in cultural policy research. In this article I will delineate a theoretical frame in which various aspects of politics are taken into account in relation to research on cultural policy histories. My thesis will be based comprised of the following three components: (1) the contingency of human action; (2) the public nature of political action, and (3) culture as a realized signifying system. Another aim is to illustrate the importance of carrying out historical research that links empirical data and theoretical research in order to successfully expound the histories of cultural policies. Furthermore, I will ar…
Modelling molecular iodine emissions in a coastal marine environment: The link to new particle formation
2006
International audience; A model of iodine chemistry in the marine boundary layer (MBL) has been used to investigate the impact of daytime coastal emissions of molecular iodine (I2). The model contains a full treatment of gas-phase iodine chemistry, combined with a description of the nucleation and growth, by condensation and coagulation, of iodine oxide nano-particles. In-situ measurements of coastal emissions of I2 made by the broadband cavity ring-down spectroscopy (BBCRDS) and inductively coupled plasma-mass spectrometry (ICP/MS) techniques are presented and compared to long path differential optical absorption spectroscopy (DOAS) observations of I2 at Mace Head, Ireland. Simultaneous me…
The seaweeds <i>Fucus vesiculosus</i> and <i>Ascophyllum nodosum</i> are significant contribu…
2013
Abstract. Based on the results of a pilot study in 2007, which found high mixing ratios of molecular iodine (I2) above the intertidal macroalgae (seaweed) beds at Mweenish Bay (Ireland), we extended the study to nine different locations in the vicinity of Mace Head Atmospheric Research Station on the west coast of Ireland during a field campaign in 2009. The mean values of I2 mixing ratio found above the macroalgae beds at nine different locations ranged from 104 to 393 ppt, implying a high source strength of I2. Such mixing ratios are sufficient to result in photochemically driven coastal new-particle formation events. Mixing ratios above the Ascophyllum nodosum and Fucus vesiculosus beds …
Crystal structure of a CsF-uranyl-salen complex. An unusual cesium-chlorine coordination.
2006
Complexation of CsF with the ditopic uranyl-salen receptor results in a solid-state structure, in which the coordination sphere of cesium is filled by ligation to one of the chlorine atoms of the solvent chloroform. This X-ray structure is the first example of chloroform ligation to an alkali-metal ion.
Monolayer graphene doping and strain dynamics induced by thermal treatments in controlled atmosphere
2018
Time dynamics of doping and strain induced in single layer graphene by thermal treatments up to 300 degrees C in vacuum, nitrogen, carbon dioxide and oxygen controlled atmosphere are deeply studied by Raman spectroscopy and they are compared with its morphological evolution investigated by Atomic Force Microscopy. The reaction dynamics in oxygen treatments is determined down to a time scale of few minutes as well as that of dedoping process made by water vapor treatment. The interplay of strain modification and doping effects is separated. The strain is clarified to be strongly influenced by the cooling time. The doping removal is dominated by the water vapor, showing that the concentration…