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Groundwater, A century of word evolution
Words, especially those that apply directly to more than one discipline, often become the object of intense debate among professionals in those disciplines. This is particularly true with those people who have to deal with technical jargon on a day-to-day basis and who are concerned that scientific facts get communicated in as clear and concise a manner as possible. Communications regarding environmental restoration projects for the US Department of Energy are no exception. Lockheed Martin Energy Systems, Inc., its subcontractors and other prime contractors often disagree about the spelling and use of compound words. This frequently results in inconsistent spelling between project reports and incorrect spelling of referenced document titles. The following discussion is an attempt to provide an objective, in-depth examination of the evolution of one particular word and recommendations for its proper and consistent use. This discussion is the result of an extensive literature search conducted within the library system at Oak Ridge National Laboratory as well as the personal geologic libraries of the author and colleagues. The author has attempted to cite only those works produced by recognized names in the related disciplines or those works that constitute common references or glossaries
Inhibition of the epidermal growth factor receptor by erlotinib prevents immortalization of human cervical cells by Human Papillomavirus type 16
AbstractThe Human Papillomavirus type-16 (HPV-16) E6 and E7 oncogenes are selectively retained and expressed in cervical carcinomas, and expression of E6 and E7 is sufficient to immortalize human cervical epithelial cells. Expression of the epidermal growth factor receptor (EGFR) is often increased in cervical dysplasia and carcinoma, and HPV oncoproteins stimulate cell growth via the EGFR pathway. We found that erlotinib, a specific inhibitor of EGFR tyrosine kinase activity, prevented immortalization of cultured human cervical epithelial cells by the complete HPV-16 genome or the E6/E7 oncogenes. Erlotinib stimulated apoptosis in cells that expressed HPV-16 E6/E7 proteins and induced senescence in a subpopulation of cells that did not undergo apoptosis. Since immortalization by HPV E6/E7 is an important early event in cervical carcinogenesis, the EGFR is a potential target for chemoprevention or therapy in women who have a high risk for cervical cancer
The last forests on Antarctica: Reconstructing flora and temperature from the Neogene Sirius Group, Transantarctic Mountains
Fossil-bearing deposits in the Transantarctic Mountains, Antarctica indicate that, despite the cold nature of the continent’s climate, a tundra ecosystem grew during periods of ice sheet retreat in the mid to late Neogene (17–2.5 Ma), 480 km from the South Pole. To date, palaeotemperature reconstruction has been based only on biological ranges, thereby calling for a geochemical approach to understanding continental climate and environment. There is contradictory evidence in the fossil record as to whether this flora was mixed angiosperm-conifer vegetation, or whether by this point conifers had disappeared from the continent. In order to address these questions, we have analysed, for the first time in sediments of this age, plant and bacterial biomarkers in terrestrial sediments from the Transantarctic Mountains to reconstruct past temperature and vegetation during a period of East Antarctic Ice Sheet retreat. From tetraether lipids (MBT’/CBT palaeothermometer), we conclude that the mean continental summer temperature was ca. 5 °C, in agreement with previous reconstructions. This was warm enough to have allowed woody vegetation to survive and reproduce even during the austral winter. Biomarkers from vascular plants indicate a low diversity and spatially variable flora consisting of higher plants, moss and algal mats growing in microenvironments in a glacial outwash system. Abietane-type compounds were abundant in some samples, indicating that conifers, most likely Podocarpaceae, grew on the Antarctic continent well into the Neogene. This is supported by the palynological record, but not the macrofossil record for the continent, and has implications for the evolution of vegetation on Antarctica
Bighorn Basin Coring Project (BBCP): a continental perspective on early Paleogene hyperthermals
During the summer of 2011, the Bighorn Basin Coring Project (BBCP) recovered over 900m of overlapping core from 3 different sites in late Paleocene to early Eocene fluvial deposits of northwestern Wyoming. BBCP cores are being used to develop high-resolution proxy records of the Paleocene–Eocene Thermal Maximum (PETM) and Eocene Thermal Maximum 2 (ETM2) hyperthermal events. These events are short-term, large magnitude global warming events associated with extreme perturbations to the earth’s carbon cycle. Although the PETM and ETM2 occurred ~55–52 million years ago, they are analogous in many ways to modern anthropogenic changes to the carbon cycle. By applying various sedimentological, geochemical, and palynological methods to the cores, we hope to better understand what caused these events, study the biogeochemical and ecological feedbacks that operated during them, and reveal precisely how they impacted continental environments.
Core recovery was > 98% in all holes and most drilling was carried out without fluid additives, showing that continuous coring of continental smectitic deposits like these can be achieved with minimal risk of contamination to molecular biomarkers. Cores were processed in the Bremen Core Repository where the science team convened for 17 days to carry out data collection and sampling protocols similar to IODP projects. Initial results show that the weathered horizon extends to as much as ~30m below the surface and variations in magnetic susceptibility within the cores record an interplay between grain size and pedogenesis. Previous investigations of outcrops near the BBCP drill sites allow detailed evaluation of the effects of weathering on common proxy methods. Studies of lithofacies, organic geochemistry, stable isotope geochemistry, calibrated XRF core scanning, paleomagnetics, and palynology are underway and will represent the highest resolution and most integrated proxy records of the PETM from a continental setting yet known. An extensive outreach program is in place to capitalize on the educational value associated with the Bighorn Basin’s unusually complete record of Phanerozoic earth history
Hamburg's Spaces of Danger: Race, Violence and Memory in a Contemporary Global City
Germany today is experiencing the strongest upsurge of right-wing populism since the second world war, most notably with the rise of Pegida and Alternative für Deutschland. Yet wealthy global cities like Hamburg continue to present themselves as the gatekeepers of liberal progress and cosmopolitan openness. This article argues that Hamburg’s urban boosterism relies on, while simultaneously obscuring, the same structures of racial violence that embolden reactionary movements. Drawing on the work of Walter Benjamin and Allan Pred, we present an archaeology of Hamburg’s landscape, uncovering some of its ‘spaces of danger’––sites layered with histories of violence, many of which lie buried and forgotten. We find that these spaces, when they become visible, threaten to undermine Hamburg’s cosmopolitan narrative. They must, as a result, be continually erased or downplayed in order to secure the city as an attractive site for capital investment. To illustrate this argument, we give three historical examples: Hamburg’s role in the Hanseatic League during the medieval and early modern period; the city under the Nazi regime; and the recent treatment of Black African refugees. The article’s main contribution is to better situate issues of historical landscape, collective memory and racialized violence within the political economy of today’s global city
Fire and brief human occupations in Iberia during MIS 4: Evidence from Abric del Pastor (Alcoy, Spain)
There is a relatively low amount of Middle Paleolithic sites in Europe dating to MIS 4. Of the few that
exist, several of them lack evidence for anthropogenic fire, raising the question of how this period
of global cooling may have affected the Neanderthal population. The Iberian Peninsula is a key area
to explore this issue, as it has been considered as a glacial refugium during critical periods of the
Neanderthal timeline and might therefore yield archaeological contexts in which we can explore
possible changes in the behaviour and settlement patterns of Neanderthal groups during MIS 4.
Here we report recent data from Abric del Pastor, a small rock shelter in Alcoy (Alicante, Spain) with
a stratified deposit containing Middle Palaeolithic remains. We present absolute dates that frame
the sequence within MIS 4 and multi-proxy geoarchaeological evidence of in situ anthropogenic fire,
including microscopic evidence of in situ combustion residues and thermally altered sediment. We also
present archaeostratigraphic evidence of recurrent, functionally diverse, brief human occupation of the
rock shelter. Our results suggest that Neanderthals occupied the Central Mediterranean coast of the
Iberian Peninsula during MIS 4, that these Neanderthals were not undergoing climatic stress and they
were habitual fire users.This research was funded by a Leakey Foundation General Grant, Spanish Ministry of Science, Innovation
and Universities Projects HAR2008-06117/HIST and HAR2015-68321-P, Junta de Castilla y León-FEDER
Project BU235P18, the LabEx Sciences Archéologiques de Bordeaux (LaScArBx ANR-10-LABX-52) and ERC
Consolidator Grant ERC-CoG-2014. Archaeological excavations at Abric del Pastor are supported by the
Archaeological Museum of Alcoy and the Government of Valencia Cultural Heritage Department
Microbial physiology and necromass regulate agricultural soil carbon accumulation
Strategies for mitigating soil organic carbon (SOC) losses in intensively managed agricultural systems typically draw from traditional concepts of soil organic matter formation, and thus emphasize increasing C inputs, especially from slowly decomposing crop residues, and reducing soil disturbance. However these approaches are often ineffective and do not adequately reflect current views of SOC cycling, which stress the important contributions of microbial biomass (MB) inputs to SOC. We examined microbial physiology as an alternate mechanism of SOC accumulation under organic (ORG) compared to conventional (CT) agricultural management practices, where ORG is accumulating C despite fewer total C inputs and greater soil tillage. We hypothesized that microbial communities in ORG have higher growth rates (MGR) and C use efficiencies (CUE) and that this relates to greater MB production and ultimately higher retention of new C inputs. We show that ORG had 50% higher CUE (±8 se) and 56% higher MGR (±22 se) relative to CT (p \u3c 0.05). From in situ13C substrate additions, we show that higher CUE and MGR are associated with greater rates and amounts of 13C glucose and phenol assimilation into MBC and mineral-associated SOC pools in ORG up to 6 mo after field substrate additions (p \u3c 0.05). ORG soils were also enriched in proteins and lipids and had lower abundances of aromatic compounds and plant lipids (p \u3c 0.05). These results illustrate a new mechanism for SOC accumulation under reduced C inputs and intensive soil disturbance and demonstrate that agricultural systems that facilitate the transformation of plant C into MB may be an effective, often overlooked strategy for building SOC in agricultural soils
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