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Author C Engrand, E Charon, H Le- Roux, M Marinova, J Duprat, E Dartois, B Guérin, J Rojas, L Delauche, M Godard, D Troadec openurl 
  Title Evidence of irradiation in interplanetary space in minerals from an ultracarbonaceous Antarctic micrometeorites (UCAMM) Type Peer-reviewed symposium
  Year 2020 Publication Lunar and Planetary Science Conference Abbreviated Journal  
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  Abstract Introduction: Ultracarbonaceous Antarctic Micrometeorites (UCAMMs) are dominated by N-rich polyaromatic organic matter exhibiting large D enrichments [1-5]. The high abundance of organic matter exhibiting large D enrichment suggests a cometary origin for UCAMMs [1-3]. Three kinds of organic matter are identified in UCAMMs, with different nitrogen abundances and highly variable concentrations of small (typically 30-500 nanometer) mineral aggregates embedded in the organic matter [5-8]. We focus here on a mineral assemblage embedded in one UCAMM that exhibits evidence of ion irradiation, to get insight on the formation and evolution of this cometary particle. Sample and methods: A fragment of UCAMM DC06-06-43 (hereafter DC06-43) was carbon coated, observed by SEM/EDX, and a 100 nm thick FIB section of this fragment was made at IEMN Lille. The size of the initial UCAMM before fragmentation was ~ 25 x 30 µm. After STXM-XANES analysis, the mineralogy of the sample was investigated by TEM at UMET Lille using a FEI Tecnai G2 20 at 200 kV and FEI TITAN Themis at 300 kV [9]. Results : TEM examination reveals a large assemblage of crystalline minerals at the center of the DC06-43 UCAMM fragment, surrounded by organic matter (Figure 1) [9]. The assemblage consists of µm-to subµm sized Mg-rich pyroxenes, a large “triskell”-shaped Fe-sulfide, a few Mg-rich olivines, and minor Si-Al-Carich amorphous pockets and Fe-Ni metal. About 28 crystalline pyroxenes are identified whereas only 5 olivine crystals are observed in the section. GEMS are present embedded in the organic matter, close to the crystalline assemblage. We identified irradiation features (rims and tracks) in pyroxene grains. No rims or tracks were found in olivine. We observed irradiated rims around six pyroxenes at the top of the section (Figure 1, light blue labels). One pyroxene shows a continuous irradiated rim (Figure 2 top). Rim thicknesses range from 20 to 100 nm, with an average of 60 ± 20 nm (1σ) (Figure 2 bottom). Fe-rich deposits are occasionally found on top of irradiated rims. EDX mappings and profiles show that the rims are strongly depleted in Mg (Figure 3). The average track density in pyroxene grains measured over an area of 4.5 x 10-8 cm 2 is 1.3 x 10 10 cm-2 with one value at 3.8 x 10 9 cm-2 , the other values ranging from 9.5 x 10 9 to 3.2 x 10 10 cm-2 (Figure 4). Irradiation track lengths  
  Programme 1120  
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  Notes Approved yes  
  Call Number Serial 7909  
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Author B Guérin, C Engrand, C Le Guillou, H Leroux, J Duprat, E Dartois, S Bernard, K Ben- Zerara, J Rojas, M Godard, L Delauche, D Troadec openurl 
  Title STEM and STXM-XANES analysis of FIB sections of Ultracarbonaceous Antarctic Micrometeorites (UCAMMs) Type Peer-reviewed symposium
  Year 2020 Publication Lunar and Planetary Science Conference, id 2117 Abbreviated Journal  
  Volume 51 Issue Pages 2117  
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  Abstract Introduction: Ultracarbonaceous Antarctic Micrometeorites (UCAMMS) are extraterrestrial dust particles containing large amount of carbonaceous material with elevated D/H ratios [1] and high N/C atomic ratio (up to 0.2)[2]. UCAMMS are rare (~ 1% of the particles in the Concordia meteorite collection) but they have been identified in several collection of interplanetary dust [3, 4]. They are most probably of cometary origin. Here, we studied the association of organic matter and minerals by scanning transmission X-ray microscopy (STXM-XANES) coupled with scanning transmission electronic microscopy (TEM/STEM). Samples and Methods: The UCAMMs studied here were collected in the Antarctic snow, close to the Concordia station at Dome C [3]. FIB sections of 8 UCAMMs (DC06-18, DC06-41, DC06-43, DC06-65, DC06-308, DC06-139, DC16-30, DC16-309) were analyzed using synchrotron based STXM-XANES at the carbon, nitrogen and oxygen K-edges. The FIB sections were subsequently analyzed with transmission electron microscopy (TEM/STEM) using a FEI Tecnai G2 20 and a FEI TITAN Themis 300 [5, 6]. Peak identification of STXM-XANES spectra are based on [7]. XANES spectra are processed and quantified using Quantorxs method [8] and quantification of STEM EDS spectra has been realized using Hyperspy software [9]. Here, we mainly present results obtained on two recently identified UCAMMs (DC06-308 and DC16-309) and compare them with previous observations [1, 5, 6]. Results: The STXM-XANES analysis reveals 3 types of organic matter (OM) characterized by different carbon speciation. Figure 1 shows type I OM in blue and type II OM in green, both having spectra close to that of chondritic insoluble organic matter (IOM). The main peaks of type I and II OMs are found around 284.8 eV (aromatic and olefinic groups (C=C)), 286.4 eV (ketone and phenol C=O) and 288.4 eV (carboxyl O=C-O). Type II OM exhibits similar functional groups as type I OM but the first peak position is shifted to 285 eV, indicating a stronger contribution of the aromatic groups. The atomic N/C ratio of types I/II OMs range between 0.01 and 0.05 (1σ=0.02) similar to those of chondritic IOM. The type III, in red on Figure 1 exhibits larger differences. The main peak is at 286.4 eV (C≡N nitrile), a small peak at 284.8 eV (alkene  
  Programme 1120  
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  Notes Approved yes  
  Call Number Serial 7910  
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Author Y. Kebukawa, M. Zolensly, J. Mathurin, E. Dartois, C. Engrand, J. Duprat, A. Deniset-Besseau, A. Dazzi, M. Fries, T. Ohigashi, D. Wakabayashi, S. Yamashita, Y. Takeichi, Y. Takahashi, M. Kondo, M. Ito, Y. Kodama, Z. Rahman, K. Kobayashi openurl 
  Title Organic matter in the Aguas Zarcas (CM2) meteorite: high abundance of aliphatic carbon in metal-rich lithology Type Peer-reviewed symposium
  Year 2020 Publication Lunar and Planetary Science Conference, id 1349 Abbreviated Journal  
  Volume 51 Issue Pages 1614  
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  Programme 1120  
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  Notes Approved yes  
  Call Number Serial 7911  
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Author J Mathurin, E Dartois, C Engrand, J Duprat, A Deniset- Besseau, A Dazzi, Y Kebukawa, T Noguchi, D Troadec openurl 
  Title Nanometre-scale infrared chemical imaging (AFM-IR) of organic matter in ultra-carbonaceous Antarctic micrometeorites (UCAMMS) and future analyses of Hayabusa 2 samples. Type Peer-reviewed symposium
  Year 2020 Publication Lunar and Planetary Science, id 1983 Abbreviated Journal  
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  Abstract Introduction: The chemical composition of organic matter (OM) in interplanetary samples (meteorites and micrometeorites) is suitably characterized by the distribution of the different chemical bonds using infrared (IR) vibrational spectroscopy (see e.g. [1]). Classical IR microscopy provides a global view of the dust grain chemical structure content but remains limited by the diffraction, with typical spot sizes sampling a few micrometers in the mid-IR range. This spatial resolution limitation is well above that of complementary techniques such as isotopic imaging with NanoSIMS or transmission electron or X-ray microscopy techniques. These techniques reveal mineralogical, chemical and isotopic heterogeneities at the sub-micron scale but do not give full access to the distribution of the various chemical bonds. The IR diffraction limitation can be circumvented by using AFM-IR microscopy. This technique opens a new window for studies of OM at ten to tens of nanometer scales and will be of importance for studies of the samples from carbonaceous asteroid Ryugu, returned by the Hayabusa 2 space probe in December 2020. AFM-IR is now a well-established microscopy technique in the vibrational field. It combines an atomic force microscope (AFM) and a tunable IR source to detect photo-thermal effect and access chemical information down to a nanoscale resolution [2]. This technique is now applied in a wide diversity of scientific fields [3], and was recently used to analyze extraterrestrial OM [4, 5]. We report here on recent results obtained on imaging two UltraCarbonaceous Antarctic MicroMeteorites (UCAMMs) using AFM-IR [5]. A small fraction of the Antarctic micrometeorites from the Concordia collection consists in UCAMMs, particles with extreme concentrations in OM, most of them exhibiting large deuterium excesses [6]. UCAMMs are also found in Japanese interplanetary dust collections [7-9]. These UCAMMs most likely originate from the surface of small icy bodies in the outer regions of the solar system [1,6,7,10]. The large OM fraction of UCAMMs (considerably higher than in the most carbon-rich meteorites) enables direct analyses without the pre-treatment generally applied to extract the OM from other meteoritic samples, and give access to unaltered chemical maps of the intimate association of minerals and organics.  
  Programme 1120  
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  Notes Approved yes  
  Call Number Serial 7912  
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Author J Rojas, J Duprat, E Dartois, T-D Wu, C Engrand, B Augé, J Mathurin, B Guerin, J-L Guerquin-Kern, Ph Boduch, H Rothard openurl 
  Title Isotopic analyses of ion irradiation-induced organic residues, clues on the formation of organics from UCAMMS Type Peer-reviewed symposium
  Year 2020 Publication Lunar and Planetary Science, id 1630 Abbreviated Journal  
  Volume 51 Issue Pages 1630  
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  Abstract Introduction: UltraCarbonaceous Antarctic Mi-croMeteorites (UCAMMs) are interplanetary dust particles that exhibit large concentrations of organic matter with high N concentrations and extreme D/H ratios [1-4]. The mineralogy, the elemental and isotopic composition of UCAMMs indicate that they most likely originate from the cometary reservoir [1, 2, 5]. Most UCAMMs exhibit large variations on D/H, 15 N/ 14 N and 13 C/ 12 C ratios at the micron or sub-micron scale. These isotopic fractionations are carried by the organic matter and their origin is still an open question. We showed that the precursors of UCAMMs can be formed by irradiation with high energy ions of N-rich ice mixtures with hydrocarbons, a process likely to take place at the surface of icy bodies orbiting beyond a nitrogen snow line and irradiated by galactic cosmic rays [2, 6]. Recent experimental simulations showed that the irradiation itself does not induce large D fractionation, but that the refractory organic residue resulting from irradiation of isotopically heterogeneous ice mixtures can exhibit large D/H spatial variation at the micron scale [7]. We performed a new series of experiments on D, 15 N and 13 C labelled ices to study the transmission of the isotopic labelled ice layers to the irradiation-induced residue. Material and method: Irradiation experiments of ices were conducted with the low-energy beam (Irrsud, 0.5-1 MeV/n) at GANIL (Caen, France). We used the IGLIAS experimental setup [8] which allows to deposit and irradiate complex ice films mixtures on substrate windows held at temperatures ranging from 8K to 300K (Figure 1). The evolution of the ices during the irradiation was monitored in situ with a Brucker Vertex 70v Fourier transform infrared (FTIR) spectrometer. The gas mixtures deposited are controlled with a Quadrupole Mass Spectrometer (QMS). We followed the same protocol as described in [7]. We first irradiated a mixture of ices made of two equally thick layers of 14 N2-CH4 (90:10) of about 5 µm each surrounding a thin layer of isotopically labeled (in D, 13 C and 15 N) ice with a thickness of about 0.2 µm. The ice films were formed by gas injections on ZnSe windows at 8K. The thickness of the central isotopically labeled ice layer was estimated from the volume of gases injected (i.e. 2% of the total thickness). The overall thickness of the ice sandwiches (11 µm) were  
  Programme 1120  
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  Notes Approved yes  
  Call Number Serial 7913  
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Author J Rojas, J Duprat, L R Nittler, J Mathurin, E Dartois, C Engrand, N Bardin, A Dazzi, A Deniset-Besseau, M Godard, J-L Guerquin-Kern, B Guerin, S Moste- Faoui, L Rémusat, R M Stroud, T-D Wu openurl 
  Title The isotopic diversity of ultracarbonaceous Antarctic micrometeorites, a coupled nanosims and afmir study Type Peer-reviewed symposium
  Year 2020 Publication Lunar and Planetary Science, : id 1614 Abbreviated Journal  
  Volume 2326 Issue Pages  
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  Programme 1120  
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  Notes Approved yes  
  Call Number Serial 7914  
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Author E. Crubezy, O. Melnichuk, A. Alexeev file  doi
openurl 
  Title Archaelogy, genetics and history 15 years of research in Yakutia (2002–2017) Type Journal
  Year 2020 Publication Vestnik arheologii, antropologii i etnografii Abbreviated Journal  
  Volume Issue 4 (51) Pages 110-119  
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  Abstract For the past 15 years, our research has focused on the evolution of the first Yakut populations, their interaction with local tribes as well as with the Russian population, which marks the beginning of Yakutia's development from the first half of the 17th century. We conducted the excavation of tombs and we analysed the cultural, historical and paleogenetic data uncovered. A review and a synthesis of the main results published in articles and monographs informs our research directions for the future.  
  Programme 1038  
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  Corporate Author Thesis Bachelor's thesis  
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  Series Volume Series Issue Edition  
  ISSN 1811-7465 ISBN (up) Medium  
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  Notes Approved yes  
  Call Number Serial 7936  
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Author Louis Le Toumelin, Charles Amory, Vincent Favier, Christoph Kittel, Stefan Hofer, Xavier Fettweis, Hubert Gallée, Vinay Kayetha file  doi
openurl 
  Title Sensitivity of the surface energy budget to drifting snow as simulated by MAR in coastal Adelie Land, Antarctica Type Journal
  Year 2020 Publication The Cryosphere Abbreviated Journal  
  Volume 15 Issue 8 Pages 3595-3614  
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  Abstract

 
  Programme 411,1013  
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  Corporate Author Thesis Bachelor's thesis  
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  Series Volume Series Issue Edition  
  ISSN 1994-0416 ISBN (up) Medium  
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  Notes Approved yes  
  Call Number Serial 7946  
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Author Luis R. Pertierra, Nicolás I. Segovia, Daly Noll, Pablo A. Martinez, Patricio Pliscoff, Andrés Barbosa, Pedro Aragón, Andrea Raya Rey, Pierre Pistorius, Phil Trathan, Andrea Polanowski, Francesco Bonadonna, Céline Le Bohec, Ke Bi, Cynthia Y. Wang-Claypool, Daniel González-Acuña, Gisele P. M. Dantas, Rauri C. K. Bowie, Elie Poulin, Juliana A. Vianna file  doi
openurl 
  Title Cryptic speciation in gentoo penguins is driven by geographic isolation and regional marine conditions: Unforeseen vulnerabilities to global change Type Journal
  Year 2020 Publication Diversity and distributions Abbreviated Journal  
  Volume 26 Issue 8 Pages 958-975  
  Keywords diversification ecological niche overlap gentoo penguin subspecies  
  Abstract Aim The conservation of biodiversity is hampered by data deficiencies, with many new species and subspecies awaiting description or reclassification. Population genomics and ecological niche modelling offer complementary new tools for uncovering functional units of phylogenetic diversity. We hypothesize that phylogenetically delineated lineages of gentoo penguins (Pygoscelis papua) distributed across Antarctica and sub-Antarctic Islands are subject to spatially explicit ecological conditions that have limited gene flow, facilitating genetic differentiation, and thereby speciation processes. Location Antarctica and sub-Antarctic area. Methods We identify divergent lineages for gentoo penguins using ddRAD-seq and mtDNA, and generated species distribution models (SDMs) based on terrestrial and marine parameters. Results Analyses of our genomic data supports the existence of four major lineages of gentoo penguin: (i) spanning the sub-Antarctic archipelagos north of the Antarctic Polar Front (APF); (ii) Kerguelen Island; (iii) South America; and (iv) across maritime Antarctic and the Scotia Arc archipelagos. The APF, a major current system around Antarctica, acts as the most important barrier separating regional sister lineages. Our ecological analyses spanning both the terrestrial (breeding sites) and marine (feeding sites) realms recover limited niche overlap among the major lineages of gentoo penguin. We observe this pattern to correspond more closely with regional differentiation of marine conditions than to terrestrial macroenvironmental features. Main conclusions Recognition of regional genetic lineages as discrete evolutionary entities that occupy distinct ecological niches and also differ morphologically should be considered a priority for conservation. Gentoo penguins provide a good example of how conservation policy can be directly impacted by new insights obtained through the integration of larger genomic datasets with novel approaches to ecological modelling. This is particularly pertinent to polar environments that are among the most rapidly changing environments on earth.  
  Programme 137,354  
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  Corporate Author Thesis Bachelor's thesis  
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  Series Volume Series Issue Edition  
  ISSN 1472-4642 ISBN (up) Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 7950  
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Author Adam T. Devlin, Jiayi Pan, Hui Lin doi  openurl
  Title Multi-Timescale Analysis of Tidal Variability in the Indian Ocean Using Ensemble Empirical Mode Decomposition Type Journal
  Year 2020 Publication Journal of Geophysical Research: Oceans Abbreviated Journal  
  Volume 125 Issue 12 Pages e2020JC016604  
  Keywords Coastal risks Ensemble Empirical Mode Decomposition Indian Ocean Sea level variability Tidal evolution Tidal variability  
  Abstract Ocean tides have been observed to be changing worldwide for nonastronomical reasons, which can combine with rising mean sea level (MSL) to increase the long-term impact to coastal regions. Tides can also exhibit variability at shorter timescales, which may be correlated with short-term variability in MSL. This short-term coupling may yield higher peak water levels and increased impacts of exceedance events that may be equally significant as long-term sea level rise. Previous studies employed the tidal anomaly correlation (TAC) method to quantify the sensitivity of tides to MSL fluctuations at long-period (>20 years) tide gauges in basin-scale surveys of the Pacific and Atlantic Ocean, finding that TACs exist at most locations. The Indian Ocean also experiences significant sea level rise and tidal variability yet has been less studied due to a sparse network of tide gauges. However, since the beginning of the 21st century, more tide gauges have been established in a wider geographical range, bringing the possibility of better estimates of tidal and MSL variability. Here, we improve the TAC approach, using the ensemble empirical mode decomposition (EEMD) method to analyze tidal amplitudes and sea level at multiple frequency bands, allowing a more effective use of shorter record tide gauges and better understanding of multiple timescales of tidal variability. We apply this approach to 73 tide gauges in the Indian Ocean to better quantify tidal variability in these under-studied regions, finding that the majority of locations exhibit significant correlations of tides and MSL.  
  Programme 688  
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  Series Volume Series Issue Edition  
  ISSN 2169-9291 ISBN (up) Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 7956  
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