2,183 research outputs found
Multispectral Recovery of a Fragment of Richard FitzRalphâs Summa de Questionibus Armenorum from University of Rochester, D.460 1000-03
Multispectral imagingâthe process of obtaining image data from a range of both visible and invisible wavelengthsâis a new frontier in medieval studies, raising the possibility of recovering damaged or palimpsested texts that have been illegible for centuries. In this paper we show the remarkable results of applying this technology to University of X, MS D.460 1000-003, a previously unidentified single-folio fragment that was gifted to the university in 1968. Formerly used as a limp vellum binding for a seventeenth-century volume, the text has become so worn that it is all but completely unreadable to the naked eye. The fragment has consequently received little scholarly attention prior to our investigation. Our team recovered nearly all of the lost text and identified the fragment as an excerpt from Richard FitzRalphâs Summa de Questionibus Armenorum. Although this text survives in 45 other manuscripts and fragments, our discovery is highly significant because the Rochester fragment is the only copy of any of FitzRalphâs works in a non-European collection. Moreover, the fragment, whose handwriting dates to no later than 1370, may be the oldest extant copy of the Summa by at least half a decade. We present the process of this discovery, our conclusions about the text, and the potential for multispectral imaging to unlock new information hidden in known but understudied fragments held in archival collections around the world
Assessing infection patterns in Chinese mystery snails from Wisconsin, USA using field and laboratory approaches
The success of invasive species establishment in new habitats depends, in part, on interactions with other members of the invaded community. Cipangopaludina chinensis, the Chinese mystery snail (CMS), is an exotic, invasive snail in North America. Since its introduction in the 1890s, CMS have spread to a number of watersheds across the United States and parts of Canada. This invasion has generated questions about the snailâs capacity to serve as a host for parasites within local habitats, including parasites with conservation implications. To begin addressing these questions, we necropsied 147 wild-caught snails from 22 lakes across Wisconsin, finding only two CMS individuals harboring trematode (flatworm) parasites. We also conducted experimental exposures using a trematode (Sphaeridiotrema pseudoglobulus) implicated in waterfowl die-offs and found that CMS infection levels were significantly lower than those in co-occurring snail species. Furthermore, the parasites that did successfully infect CMS were often found encased in the shells of the snails in a non-viable state. Together these results 1) provide insight into the importance of CMS as a host for parasites in the region, and 2) may help to explain the wide distribution of CMS across WI and the Midwest
Does language context impact the neural correlates of executive control in monolingual and multilingual young adults?
Some previous studies have shown that creating a language context in which words from both languages are interspersed into a flanker task improves executive control performance for bilinguals, but these studies have produced inconsistent results. The studies have used different versions of the task and not included monolinguals, limiting generalization. Here, English-Chinese multilinguals and English monolinguals performed a flanker task while EEG was recorded. There were three language context blocks â English, Chinese, or both â and participants were instructed to ignore the interspersed words. Multilinguals displayed faster flanker RTs and earlier P2 and N2 waveforms than monolinguals. There was also a significant correlation between the P2/N2 latency and reaction times, connecting these waveforms to behavior. Finally, P2 amplitude differed between groups in the mixed context, and language context impacted P3 amplitude for monolinguals but not multilinguals. These results are interpreted in terms of language context effects on monolingual executive function processing and possible difference in bilingual experience between current participants and those in previous studies
Non-Markovian Momentum Computing: Universal and Efficient
All computation is physically embedded. Reflecting this, a growing body of
results embraces rate equations as the underlying mechanics of thermodynamic
computation and biological information processing. Strictly applying the
implied continuous-time Markov chains, however, excludes a universe of natural
computing. We show that expanding the toolset to continuous-time hidden Markov
chains substantially removes the constraints. The general point is made
concrete by our analyzing two eminently-useful computations that are impossible
to describe with a set of rate equations over the memory states. We design and
analyze a thermodynamically-costless bit flip, providing a first counterexample
to rate-equation modeling. We generalize this to a costless Fredkin gate---a
key operation in reversible computing that is computation universal. Going
beyond rate-equation dynamics is not only possible, but necessary if stochastic
thermodynamics is to become part of the paradigm for physical information
processing.Comment: 6 pages, 3 figures; Supplementary Material, 1 page;
http://csc.ucdavis.edu/~cmg/compmech/pubs/cbdb.ht
UAS Surveillance Criticality
The integration of unmanned aircraft systems (UAS) into the national airspace system (NAS) poses considerable challenges. Maintaining human safety is perhaps chief among these challenges as UAS remote pilots will need to interact with other UAS, piloted aircraft, and other conditions associated with flight. A research team of 6 leading UAS research universities was formed to respond to a set of surveillance criticality research questions. Five analysis tools were selected following a literature review to evaluate airborne surveillance technology performance. The analysis tools included: Fault Trees, Monte Carlo Simulations, Hazard Analysis, Design of Experiments (DOE), and Human-in-the-Loop Simulations. The Surveillance Criticality research team used results from these analyses to address three primary research questions and provide recommendations for UAS detect-and-avoid mitigation and areas for further research
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Accounting for changing temperature patterns increases historical estimates of climate sensitivity
Eight atmospheric general circulation models (AGCMs) are forced with observed historical (1871â2010) monthly sea surface temperature and sea ice variations using the Atmospheric Model Intercomparison Project II data set. The AGCMs therefore have a similar temperature pattern and trend to that of observed historical climate change. The AGCMs simulate a spread in climate feedback similar to that seen in coupled simulations of the response to CO2 quadrupling. However, the feedbacks are robustly more stabilizing and the effective climate sensitivity (EffCS) smaller. This is due to a pattern effect, whereby the pattern of observed historical sea surface temperature change gives rise to more negative cloud and longwave clearâsky feedbacks. Assuming the patterns of longâterm temperature change simulated by models, and the radiative response to them, are credible; this implies that existing constraints on EffCS from historical energy budget variations give values that are too low and overly constrained, particularly at the upper end. For example, the pattern effect increases the longâterm Otto et al. (2013, https://doi.org/10.1038/ngeo1836) EffCS median and 5â95% confidence interval from 1.9 K (0.9â5.0 K) to 3.2 K (1.5â8.1 K
An Efficient, FPGA-Based, Cluster Detection Algorithm Implementation for a Strip Detector Readout System in a Time Projection Chamber Polarimeter
A fundamental challenge in a spaceborne application of a gas-based Time Projection Chamber (TPC) for observation of X-ray polarization is handling the large amount of data collected. The TPC polarimeter described uses the APV-25 Application Specific Integrated Circuit (ASIC) to readout a strip detector. Two dimensional photoelectron track images are created with a time projection technique and used to determine the polarization of the incident X-rays. The detector produces a 128x30 pixel image per photon interaction with each pixel registering 12 bits of collected charge. This creates challenging requirements for data storage and downlink bandwidth with only a modest incidence of photons and can have a significant impact on the overall mission cost. An approach is described for locating and isolating the photoelectron track within the detector image, yielding a much smaller data product, typically between 8x8 pixels and 20x20 pixels. This approach is implemented using a Microsemi RT-ProASIC3-3000 Field-Programmable Gate Array (FPGA), clocked at 20 MHz and utilizing 10.7k logic gates (14% of FPGA), 20 Block RAMs (17% of FPGA), and no external RAM. Results will be presented, demonstrating successful photoelectron track cluster detection with minimal impact to detector dead-time
EVALUATING ARTIFICIAL INTELLIGENCE METHODS FOR USE IN KILL CHAIN FUNCTIONS
Current naval operations require sailors to make time-critical and high-stakes decisions based on uncertain situational knowledge in dynamic operational environments. Recent tragic events have resulted in unnecessary casualties, and they represent the decision complexity involved in naval operations and specifically highlight challenges within the OODA loop (Observe, Orient, Decide, and Assess). Kill chain decisions involving the use of weapon systems are a particularly stressing category within the OODA loopâwith unexpected threats that are difficult to identify with certainty, shortened decision reaction times, and lethal consequences. An effective kill chain requires the proper setup and employment of shipboard sensors; the identification and classification of unknown contacts; the analysis of contact intentions based on kinematics and intelligence; an awareness of the environment; and decision analysis and resource selection. This project explored the use of automation and artificial intelligence (AI) to improve naval kill chain decisions. The team studied naval kill chain functions and developed specific evaluation criteria for each function for determining the efficacy of specific AI methods. The team identified and studied AI methods and applied the evaluation criteria to map specific AI methods to specific kill chain functions.Civilian, Department of the NavyCivilian, Department of the NavyCivilian, Department of the NavyCaptain, United States Marine CorpsCivilian, Department of the NavyCivilian, Department of the NavyApproved for public release. Distribution is unlimited
A Simulation Study of the Factors Influencing the Risk of Intraoperative Slipping
AbstractBackgroundTo identify the impact of weight, table surface, and table type on slipping in a simulation of minimally invasive gynecologic surgery.MethodsA mannequin was placed into increasing Trendelenburg until a slip was observed; the table angle at the time of the event was measured (slip angle). The influence of mannequin position (supine vs. lithotomy), weight, table surface, and model was evaluated. A linear regression model was used to analyze the data.ResultsMannequin weight, bed surface, and bed type all significantly impacted the slip angles. In general, higher mannequin weights tolerated significantly more Trendelenburg before slipping in the supine position but less in lithotomy compared to lower weights. In lithotomy, the disposable sheet and gelpad performed worse than the bean bag, egg crate foam, and bedsheet. There was no difference in slipping because of bed surface in the supine model. The Skytron operating table performed significantly better than the Steris operating table when tested with the bedsheet.ConclusionOperative position, patient weight, and bed surface together influence the slipping propensity. In lithotomy, heavier patients were more prone to slipping while the inverse was true in supine. The egg crate foam, bean bag, and bedsheet were the best antislip surfaces. Operating room table choice can mitigate slippage
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