| 1. |
- Asoni, Andrea, et al.
(författare)
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A mercenary army of the poor? Technological change and the demographic composition of the post-9/11 US military
- 2022
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Ingår i: Journal of Strategic Studies. - : Taylor & Francis Ltd. - 1743-937X .- 0140-2390. ; 45:4, s. 568-614
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Tidskriftsartikel (refereegranskat)abstract
- We test two sets of alternative hypotheses about the demographic composition of the U.S. armed forces. We analyse individual-level data of two national representative samples covering the period 1979-2008. We find that, in contrast to the accepted wisdom, the U.S. military no longer primarily recruits individuals from the most disadvantaged socio-economic backgrounds. Technological, tactical, operational and doctrinal changes have led to a change in the demand for personnel. As a result, on different metrics such as family income and family wealth as well as cognitive abilities, military personnel are on average like the average American citizen or slightly better.
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| 2. |
- Bauer, Franz E., et al.
(författare)
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A new, faint population of X-ray transients
- 2017
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Ingår i: Monthly Notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 467:4, s. 4841-4857
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Tidskriftsartikel (refereegranskat)abstract
- We report on the detection of a remarkable new fast high-energy transient found in the Chandra Deep Field-South, robustly associated with a faint (mR = 27.5mag, zph ~2.2) host in the CANDELS survey. The X-ray event is comprised of 115+12 -11 net 0.3-7.0 keV counts, with a light curve characterized by an ~100 s rise time, a peak 0.3-10 keV flux of ~5 × 10-12 erg s-1 cm-2 and a power-law decay time slope of -1.53 ± 0.27. The average spectral slope is Γ = 1.43+0.23 -0.13, with no clear spectral variations. The X-ray and multiwavelength properties effectively rule out the vast majority of previously observed highenergy transients. A few theoretical possibilities remain: an 'orphan' X-ray afterglow from an off-axis short-duration gamma-ray burst (GRB) with weak optical emission, a low-luminosity GRB at high redshift with no prompt emission below ~20 keV rest frame, or a highly beamed tidal disruption event (TDE) involving an intermediate-mass black hole and a white dwarf with little variability. However, none of the above scenarios can completely explain all observed properties. Although large uncertainties exist, the implied rate of such events is comparable to those of orphan and low-luminosity GRBs as well as rare TDEs, implying the discovery of an untapped regime for a known transient class, or a new type of variable phenomena whose nature remains to be determined.
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| 3. |
- Cusminsky, Gabriela, et al.
(författare)
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Late quaternary environmental changes in Patagonia as inferred from lacustrine fossil and extant ostracods
- 2011
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Ingår i: Biological Journal of the Linnean Society. - : Oxford University Press (OUP). - 0024-4066. ; 103:2, s. 397-408
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Tidskriftsartikel (refereegranskat)abstract
- In the present study, we compare modern and Quaternary ostracods from two lacustrine basins: Laguna Cari-Laufquen (41 degrees S) and Lago Cardiel (49 degrees S) in Patagonia. Taxonomic and quantitative analyses along with isotopic and chemical studies of the extant ostracod fauna indicate that distinct ostracod associations can be identified as a function of conductivity. Three ostracod associations can be distinguished: (1) springs, ponds and small creeks, characterized by low conductivity (e. g. 1015 ms cm(-1)); (2) lakes and permanent ponds, characterized by medium conductivity (e. g. 1625 ms cm(-1)) and (3) ephemeral lacustrine environments, generally characterized by higher conductivity (e. g. 16 480 ms cm(-1)) These modern ostracod associations were also identified in older sequences from sediments outcropping in the Laguna Cari-Laufquen current shoreline, as well as in sediment cores from Lago Cardiel. The predominance of Limnocythere rionegroensis Cusminsky & Whatley in the Cari-Laufquen sections suggests the development of a saline and turbid lake during the Late Pleistocene and Early Holocene, and thus higher precipitation at these latitudes. Changes in ostracod abundance and associations have been observed in Lago Cardiel during the last approximately 16 000 calibrated years BP. Conductivity is known to change as a function of the ratio of precipitation to evaporation and a decrease in conductivity from the Late Pleistocene to the Middle Holocene suggests substantial hydrological variations (i. e. increase of the precipitation/ evaporation ratio suggests minor conductivity). These two examples show that ostracods provide an excellent proxy for interpreting palaeoclimatic and palaeoenvironmental changes in Patagonia. (C) 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 103, 397-408.
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