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High-resolution digital elevation models of Finland and Sweden based on LiDAR (Light Detection and Ranging) reveal subglacial landforms in great detail. We describe the ice-sheet scale distribution and morphometric characteristics of a glacial landform that is distinctive in morphology and occurs commonly in the central parts of the former Scandinavian Ice Sheet, especially up-ice of the Younger Dryas end moraine zone. We refer to these triangular or V-shaped landforms as murtoos (singular, ‘murtoo’). Murtoos are typically 30–200 m in length and 30–200 m in width with a relief of commonly <5 m. Murtoos have straight and steep edges, a triangular tip oriented parallel to ice-flow direction, and an asymmetric longitudinal profile with a shorter, but steeper down-ice slope. The spatial distribution of murtoos and their geomorphic relation to other landforms indicate that they formed subglacially during times of climate warming and rapid retreat of the Scandinavian Ice Sheet when large amounts of meltwater were delivered to the bed. Murtoos are formed under warm-based ice and may be associated with a non-channelized subglacial hydraulic system that evacuated large discharges of subglacial water.
Plant growth stage and temperature influence the activity of glyphosate on common lambsquarters. A biotype of common lambsquarters in Dickinson County, KS (DK) was not controlled upon treatment with glyphosate in the field. In a greenhouse dose–response study, the DK biotype expressed 1.5-fold less sensitivity to glyphosate compared to a known susceptible biotype from Riley County, KS (RL). Common lambsquarters plants were treated at different growth stages (5 to 7, 10 to 12, 15 to 17, or 19 to 21 cm tall) with glyphosate at a field rate (840 g ae ha–1), and, regardless of the biotype, plants were more susceptible to glyphosate when they were 5 to 7 cm tall. Common lambsquarters plants were treated with glyphosate (840 g ae ha–1) after growing at different temperatures (25/15, 32.5/22.5, or 40/30 C day/night), and regardless of the biotype, plants were more susceptible to glyphosate when grown at 25/15 C. The results suggest that the DK biotype exhibits reduced sensitivity to glyphosate compared to the RL biotype, and glyphosate applied at field rate would be more effective on smaller common lambsquarters plants and at cooler temperatures. Common lambsquarters seedlings tend to emerge when temperatures are cooler, early in the spring relative to other summer annual weeds. Therefore, plants should be identified and treated earlier in the growing season for best efficacy with glyphosate.
The surface waters of the Southern Ocean play a key role in the global climate and carbon cycles by promoting growth of some of the world’s largest phytoplankton blooms. Several studies have emphasized the importance of glacial and sediment inputs of Fe that fuel the primary production of the Fe-limited Southern Ocean. Although the fertile surface waters along the shelf of the western Antarctic Peninsula (WAP) are influenced by large inputs of freshwater, this freshwater may take multiple pathways (e.g. calving, streams, groundwater discharge) with different degrees of water-rock interactions leading to variable Fe flux to coastal waters. During the summers of 2012–13 and 2013–14, seawater samples were collected along the WAP, near Anvers Island, to observe water column dynamics in nearshore and offshore waters. Tracers (223,224Ra, 222Rn, 18O, 2H) were used to evaluate the source and transport of water and nutrients in coastal fjords and across the shelf. Coastal waters are compared across two field seasons, with increased freshwater observed during 2014. Horizontal mixing rates of water masses along the WAP ranged from 110–3600 m2 s-1. These mixing rates suggest a rapid transport mechanism for moving meltwater offshore.
The complex of Niuheliang, in north-eastern China, with its concentration of ceremonial architecture and unusual art, has been considered the most highly developed polity of the Hongshan period, representing the integration of a large territory. In contrast, the supposed absence of residential remains has been advanced to suggest that it was a vacant ceremonial centre. Systematic survey of the area is now helping to clarify relationships between ceremonial sites and occupation patterns. Densities of utilitarian pottery sherds were used to map settlement and estimate population levels in relation to the locations of ceremonial architecture and concentrations of ritual pottery. This reveals that despite unproductive soils, the area had a relatively high, although scattered, population, focused in part on ritual locations. The results support a role for Niuheliang as a place of pilgrimage, but within a nexus of settled communities that sustained its ceremonial activities.
Cen X-3 was first discovered by Chodil et al. Since then, observations using the UHURU satellite have shown it to be an X-ray pulsar, and it must now have become one of the most searched for objects in the sky. It is both an X-ray pulsar (P~4.8 secs) and an X-ray eclipsing binary (P~2.08712 days).
Experiments on the National Ignition Facility show that multi-dimensional effects currently dominate the implosion performance. Low mode implosion symmetry and hydrodynamic instabilities seeded by capsule mounting features appear to be two key limiting factors for implosion performance. One reason these factors have a large impact on the performance of inertial confinement fusion implosions is the high convergence required to achieve high fusion gains. To tackle these problems, a predictable implosion platform is needed meaning experiments must trade-off high gain for performance. LANL has adopted three main approaches to develop a one-dimensional (1D) implosion platform where 1D means measured yield over the 1D clean calculation. A high adiabat, low convergence platform is being developed using beryllium capsules enabling larger case-to-capsule ratios to improve symmetry. The second approach is liquid fuel layers using wetted foam targets. With liquid fuel layers, the implosion convergence can be controlled via the initial vapor pressure set by the target fielding temperature. The last method is double shell targets. For double shells, the smaller inner shell houses the DT fuel and the convergence of this cavity is relatively small compared to hot spot ignition. However, double shell targets have a different set of trade-off versus advantages. Details for each of these approaches are described.
Waterhemp is an increasingly problematic weed in the U.S. Midwest, having now evolved resistances to herbicides from six different site-of-action groups. Glyphosate-resistant waterhemp in the Midwest is especially concerning given the economic importance of glyphosate in corn and soybean production. Amplification of the target-site gene, 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) was found to be the mechanism of glyphosate resistance in Palmer amaranth, a species closely related to waterhemp. Here, the relationship between glyphosate resistance and EPSPS gene amplification in waterhemp was investigated. Glyphosate dose response studies were performed at field sites with glyphosate-resistant waterhemp in Illinois, Kansas, Kentucky, Missouri, and Nebraska, and relative EPSPS copy number of survivors was determined via quantitative real-time polymerase chain reaction (qPCR). Waterhemp control increased with increasing glyphosate rate at all locations, but no population was completely controlled even at the highest rate (3,360 g ae ha−1). EPSPS gene amplification was present in plants from four of five locations (Illinois, Kansas, Missouri, and Nebraska) and the proportion of plants with elevated copy number was generally higher in survivors from glyphosate-treated plots than in plants from the untreated control plots. Copy number magnitude varied by site, but an overall trend of increasing copy number with increasing rate was observed in populations with gene amplification, suggesting that waterhemp plants with more EPSPS copies are more resistant. Survivors from the Kentucky population did not have elevated EPSPS copy number. Instead, resistance in this population was attributed to the EPSPS Pro106Ser mutation. Results herein show a quantitative relationship between glyphosate resistance and EPSPS gene amplification in some waterhemp populations, while highlighting that other mechanisms also confer glyphosate resistance in waterhemp.
The Wisconsin Plasma Astrophysics Laboratory (WiPAL) is a flexible user facility designed to study a range of astrophysically relevant plasma processes as well as novel geometries that mimic astrophysical systems. A multi-cusp magnetic bucket constructed from strong samarium cobalt permanent magnets now confines a
, fully ionized, magnetic-field-free plasma in a spherical geometry. Plasma parameters of
provide an ideal testbed for a range of astrophysical experiments, including self-exciting dynamos, collisionless magnetic reconnection, jet stability, stellar winds and more. This article describes the capabilities of WiPAL, along with several experiments, in both operating and planning stages, that illustrate the range of possibilities for future users.
We used the winter of 2009–2010, which had minimal influenza circulation due to the earlier 2009 influenza A(H1N1) pandemic, to test the accuracy of ecological trend methods used to estimate influenza-related deaths and hospitalizations. We aggregated weekly counts of person-time, all-cause deaths, and hospitalizations for pneumonia/influenza and respiratory/circulatory conditions from seven healthcare systems. We predicted the incidence of the outcomes during the winter of 2009–2010 using three different methods: a cyclic (Serfling) regression model, a cyclic regression model with viral circulation data (virological regression), and an autoregressive, integrated moving average model with viral circulation data (ARIMAX). We compared predicted non-influenza incidence with actual winter incidence. All three models generally displayed high accuracy, with prediction errors for death ranging from −5% to −2%. For hospitalizations, errors ranged from −10% to −2% for pneumonia/influenza and from −3% to 0% for respiratory/circulatory. The Serfling and virological models consistently outperformed the ARIMAX model. The three methods tested could predict incidence of non-influenza deaths and hospitalizations during a winter with negligible influenza circulation. However, meaningful mis-estimation of the burden of influenza can still result with outcomes for which the contribution of influenza is low, such as all-cause mortality.
The purpose of this investigation was to compare a new psychotherapy for bulimia nervosa (BN), integrative cognitive-affective therapy (ICAT), with an established treatment, ‘enhanced’ cognitive-behavioral therapy (CBT-E).
Eighty adults with symptoms of BN were randomized to ICAT or CBT-E for 21 sessions over 19 weeks. Bulimic symptoms, measured by the Eating Disorder Examination (EDE), were assessed at baseline, at the end of treatment (EOT) and at the 4-month follow-up. Treatment outcome, measured by binge eating frequency, purging frequency, global eating disorder severity, emotion regulation, self-oriented cognition, depression, anxiety and self-esteem, was determined using generalized estimating equations (GEEs), logistic regression and a general linear model (intent-to-treat).
Both treatments were associated with significant improvement in bulimic symptoms and in all measures of outcome, and no statistically significant differences were observed between the two conditions at EOT or follow-up. Intent-to-treat abstinence rates for ICAT (37.5% at EOT, 32.5% at follow-up) and CBT-E (22.5% at both EOT and follow-up) were not significantly different.
ICAT was associated with significant improvements in bulimic and associated symptoms that did not differ from those obtained with CBT-E. This initial randomized controlled trial of a new individual psychotherapy for BN suggests that targeting emotion and self-oriented cognition in the context of nutritional rehabilitation may be efficacious and worthy of further study.
Societies in many regions all over the world started down the path toward large-scale social formations, so the number of trajectories available for comparative study is large. Although most of these regional trajectories are not well known, the few that are well enough documented for comparative study are more than comparisons can easily handle. A focus on early civilizations leads to comparing large world areas (Mesopotamia, Nile Valley, North China, Mesoamerica, Central Andes, etc.) because early civilizations are very large-scale social formations – finally, each of these world areas contained only one civilization. The beginnings of large social formations, which is the subject of this chapter, however, can be found in multiple separate regions within any of these areas. It is the specific trajectories of societal change within these smaller regions that we seek to compare, not culture-historical constructs like archaeological cultures, horizons, or traditions. For comparing trajectories, attention must be focused on human activities and the organization of social relationships in a place, and culture history is not the most effective or direct approach to these subjects. We treat each regional trajectory as a separate instance to be compared with others.
This chapter lays aside the data threads spun around differentiation in Chapter 5 in order to focus on those most directly connected to the emergence and growth of supra-local communities: local community structure, supra-local community scale, supra-local community centralization, demographic density, public works investment, tax rate, and conflict. Estimation of ancient populations and labor investment in public works lies at the core of the comparisons presented here. At least some archaeologists have long been willing to make such estimates, but the task should only be attempted by archaeologists willing to “dare to be inaccurate” (cf. Martens 2008:1160). Although the empirical basis for archaeological population and labor investment estimates is far better than it was twenty years ago, both still come with very wide error ranges. They can be put to effective use, but only if we adopt the attitude required for solving what have come to be called Fermi problems in the natural sciences, where the vital role played by quick calculations on cocktail napkins is thoroughly appreciated (Morrison 1963; Weinstein and Adam 2008). The comparisons we offer here are based on more rigorous use of empirical data than the solutions to Fermi problems often are, but the reader is forewarned that we have not let the imprecision of archaeological population or labor investment estimates stop us. We have been willing to work with sometimes uncomfortably large error ranges in order to see what kind of conclusions the best information now available leads toward. We offer them as cocktail napkin calculations; readers more interested in data precision than in the heuristic value of seeing where even imprecise data might lead should probably stop here. Those willing to join us in being as careful as possible with the data but riding roughshod when necessary, should read on. The sources of the empirical information we have used and the nature of our analyses are discussed in the appendix.
As archaeologists, we seek to understand variation and change in past human societies. This goal necessitates a comparative approach, and comparisons justify the broad cross-cultural and diachronic scope of our work. Without comparisons we sink into the culture-bound theorizing against which anthropology and archaeology have long sought to broaden social science research. By undertaking comparisons that incorporate long-term social variability, archaeologists not only improve our understanding of the past, but also open the door to meaningful transdisciplinary research. Archaeologists have unique and comprehensive data sets whose analysis can contribute to dialogues surrounding contemporary issues and the myriad challenges of our era.
In the past two decades, the pendulum seems to have swung away from comparative research in archaeology. Many archaeologists focus on detailed contextual descriptions of individual cases, and only a few have dedicated themselves to explicit comparative work. Yet in that same time span, fieldwork has expanded tremendously throughout the world, leading to an explosion of well-documented diachronic data on sites and regions. We now have substantial detail on the variation inherent in phenomena such as cultural assemblages, settlement patterns, and economic activity. New methods, from dating techniques to digital data processing, promote comparative analysis and greatly advance our understanding of human societies and change. The time is ripe for a renewed commitment to comparative research in archaeology.
Early complex society studies, like anthropology in general, are strongly rooted in comparative analysis. Cultural evolutionists of the mid-nineteenth century (Tylor 1865; Morgan 1877; Spencer 1880–97) relied entirely on comparative ethnography to create speculative accounts of the antecedents of contemporary societies. A century later, Sahlins (Sahlins and Service 1960), Service (1962), Fried (1967), and other scholars did the same without assuming that “savages” would naturally aspire to better things, and slowly work their way through “barbarism” toward the “civilized” condition of Victorian Britain. Value-neutral vocabulary was sought and forces driving social change were considered, but the entire comparative enterprise still depended on imagining that some contemporary societies were like the unknown ancestors of other more complex contemporary societies. There was virtually no direct information about human societies before those that could be observed in the ethnographic present or through historical sources.
By the beginning of the twenty-first century, that situation has changed dramatically. It is no longer necessary to speculate about diachronic processes from synchronic snapshots of societies not historically related to each other, because of a flood of direct archaeological evidence about long-term trajectories of social change. We still do not know as much about the past of any region as we would like to, but we do now know more about many regions than we are fully able to make sense of. Comparative study is important to this task of, quite literally, making sense of abundant detailed information. It was exactly this that the early cultural evolutionists were doing with their comparative ethnography: making sense of a welter of ethnographic detail. Scholars from Morgan to Service and Fried offered understanding by placing ethnographically known contemporary societies in an imaginary developmental sequence. Since the sequence was based on nothing more than ethnographic information about contemporary unrelated societies, it is remarkable how much the cultural evolutionists got right about the past ten thousand years of human history.
We report an experimental study of photocarrier lifetime, transport, and excitation spectra in silicon-on-insulator doped with sulfur far above thermodynamic saturation. The spectral dependence of photocurrent in coplanar structures is consistent with photocarrier generation throughout the hyperdoped and undoped sub-layers, limited by collection of holes transported along the undoped layer. Holes photoexcited in the hyperdoped layer are able to diffuse to the undoped layer, implying (μτ)h ∼ 5 × 10−9 cm2/V. Although high absorptance of hyperdoped silicon is observed from 1200 to 2000 nm in transmission experiments, the number of collected electrons per absorbed photon is 10−4 of the above-bandgap response of the device, consistent with (μτ)e < 1 × 10−7cm2/V.
To date, there have been no reports of Dalmatian toadflax serving as a host for cucumber mosaic virus (CMV). Infestations of Dalmatian toadflax may serve as a reservoir of CMV, thereby facilitating aphid transmission of CMV to both agricultural crops and native plants. The goal of this study was to determine whether Dalmatian toadflax is a host for CMV. Dalmatian toadflax seedlings were randomly assigned to two treatments (18 replicates/treatment): no inoculation (control) and inoculation with CMV (Fast New York strain). The Dalmatian toadflax seedlings were inoculated by standard mechanical methods and tested for the presence of CMV using enzyme-linked immunosorbent assay (ELISA). Ten of the 18 CMV-inoculated toadflax plants tested positive for the virus; 6 of the 18 displayed systemic mosaic chlorosis and leaf curling. All control plants tested negative. Transmission electron microscopy obtained from CMV-positive plants confirmed the presence of CMV based on physical properties. To verify CMV infestation, tobacco plants were assigned to the following treatments (six replicates/treatment): no inoculation (control), CMV-negative (control) inoculation, and a CMV-positive inoculation. Plants were inoculated by standard methods. Five of the 6 tobacco plants treated with the CMV-positive inoculum tested positive for CMV using ELISA. All control plants tested negative for the virus.
The deposition and post-treatment processes involved in the production of porous organosilicate glasses (OSGs) by plasma-enhanced chemical vapor deposition (PECVD) with ultraviolet light (UV) treatment are investigated through the use of a deuterated organic porogen precursor using infrared spectroscopy and solid-state nuclear magnetic resonance spectroscopy. Infrared analysis provides evidence for hydrogen-deuterium scrambling between the chemical species during the deposition process, which is exacerbated by the UV treatment process. Analysis of 13C cross-polarized magic angle spinning (CP-MAS) NMR suggests that the porogen exists in domains relatively isolated from the network, in agreement with short UV treatment time morphological data that indicates the pore size is relatively constant from the early stages of UV treatment process. The chemical and morphological information provides further support for a deposition controlled morphology and has implications towards enhanced chemical processing of porous organosilicate glass (OSG) films for back-end-of-line integrated circuit manufacturing.