1,832 research outputs found

    Classifying visual field loss in glaucoma through baseline matching of stable reference sequences

    Get PDF
    Glaucoma is a common disease of the eye that often results in partial blindness. The main symptom of glaucoma is progressive loss of sight in the visual field over time. The clinical management of glaucoma involves monitoring the progress of the disease using a sequence of regular visual field tests. However, there is currently no universally accepted standard method for classifying changes in the visual field test data. Sequence matching techniques typically rely on similarity measures. However, visual field measurements are very noisy, particularly in people with glaucoma. It is therefore difficult to establish a reference data set including both stable and progressive visual fields. This paper proposes a method that uses a "baseline" computed from a query sequence, to match stable sequences in a database of visual field measurements collected from volunteers. The purpose of the new method is to classify a given query sequence as being stable or progressive. The results suggest that the new method gives a significant improvement in accuracy for identifying progressive sequences, though there is a small penalty for stable sequences

    On crowdsourcing relevance magnitudes for information retrieval evaluation

    Get PDF
    4siMagnitude estimation is a psychophysical scaling technique for the measurement of sensation, where observers assign numbers to stimuli in response to their perceived intensity. We investigate the use of magnitude estimation for judging the relevance of documents for information retrieval evaluation, carrying out a large-scale user study across 18 TREC topics and collecting over 50,000 magnitude estimation judgments using crowdsourcing. Our analysis shows that magnitude estimation judgments can be reliably collected using crowdsourcing, are competitive in terms of assessor cost, and are, on average, rank-aligned with ordinal judgments made by expert relevance assessors. We explore the application of magnitude estimation for IR evaluation, calibrating two gain-based effectiveness metrics, nDCG and ERR, directly from user-reported perceptions of relevance. A comparison of TREC system effectiveness rankings based on binary, ordinal, and magnitude estimation relevance shows substantial variation; in particular, the top systems ranked using magnitude estimation and ordinal judgments differ substantially. Analysis of the magnitude estimation scores shows that this effect is due in part to varying perceptions of relevance: different users have different perceptions of the impact of relative differences in document relevance. These results have direct implications for IR evaluation, suggesting that current assumptions about a single view of relevance being sufficient to represent a population of users are unlikely to hold.partially_openopenMaddalena, Eddy; Mizzaro, Stefano; Scholer, Falk; Turpin, AndrewMaddalena, Eddy; Mizzaro, Stefano; Scholer, Falk; Turpin, Andre

    Oligomers, organosulfates, and nitrooxy organosulfates in rainwater identified by ultra-high resolution electrospray ionization FT-ICR mass spectrometry

    Get PDF
    Wet deposition is an important removal mechanism for atmospheric organic matter, and a potentially important input for receiving ecosystems, yet less than 50% of rainwater organic matter is considered chemically characterized. Precipitation samples collected in New Jersey, USA, were analyzed by negative ion ultra-high resolution electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Elemental compositions of 552 unique molecular species were determined in the mass range 50–500 Da in the rainwater. Four main groups of organic compounds were identified: compounds containing carbon, hydrogen, and oxygen (CHO) only, sulfur (S) containing CHOS compounds, nitrogen (N) containing CHON compounds, and S- and N- containing CHONS compounds. Organic acids commonly identified in precipitation were detected in the rainwater. Within the four main groups of compounds detected in the rainwater, oligomers, organosulfates, and nitrooxy-organosulfates were assigned based on elemental formula comparisons. The majority of the compounds identified are products of atmospheric reactions and are known contributors to secondary organic aerosol (SOA) formed from gas phase, aerosol phase, and in-cloud reactions in the atmosphere. It is suggested that the large uncharacterized component of SOA is the main contributor to the large uncharacterized component of rainwater organic matter

    Conical refraction with low-coherence light sources

    Get PDF
    We report on conical refraction (CR) with low-coherence light sources, such as light-emitting diodes and decoherentized HeNe laser radiation, and demonstrate different CR patterns. In our experiments, a variation of the pinhole sizes from 25 to 100 ”m and the distances to pinhole from 50 to 5 cm reduced spatial coherence of radiation that resulted in the disappearance of the dark Poggendorff’s ring in the Lloyd’s plane. This is attributed to the interference nature of the Lloyd’s distribution and found to be in excellent agreement with the paraxial dual-cone model of conical refraction

    Intermolecular interaction of photoexcited Cu(TMpy-P4) with water studied by transient resonance Raman and picosecond absorption spectroscopies

    Get PDF
    photoinduced complex between Cu(TMpy-P4) and water molecules, reversibly axially coordinated to the central metal, was observed in picosecond transient absorption and nanosecond resonance Raman experiments. This complex is rapidly created (τ1 = 15 ± 5 ps) in the excited triplet (π, π*) state of Cu-porphyrin, and the subsequent relaxation is proposed to proceed via two parallel pathways. One is fast and efficient (≄90% of molecules), and presumably involves a (π, d) charge-transfer state. The second pathway is slow (τ2 >> 1 ns), has a low quantum yield (≀10%) and involves the excited (d, d) state which is responsible for transient Raman features at ≈ 1553 cm−1 (Îœ2*) and ≈ 1347 cm−1 (Îœ4*), and for low-intensity long-lived transient absorption features

    Brain activation covaries with reported criminal behaviors when making risky choices: A fuzzy-trace theory approach

    Get PDF
    This is the author accepted manuscript. The final version is available from the American Psychological Association via the DOI in this record.Criminal behavior has been associated with abnormal neural activity when people experience risks and rewards or exercise inhibition. However, neural substrates of mental representations that underlie criminal and noncriminal risk-taking in adulthood have received scant attention. We take a new approach, applying fuzzy-trace theory, to examine neural substrates of risk preferences and criminality. We extend ideas about gist (simple meaning) and verbatim (precise risk-reward tradeoffs) representations used to explain adolescent risk-taking to uncover neural correlates of developmentally inappropriate adult risk-taking. We tested predictions using a risky-choice framing task completed in the MRI scanner, and examined neural covariation with self-reported criminal and noncriminal risk-taking. As predicted, risk-taking was correlated with a behavioral pattern of risk preferences called “reverse framing” (preferring sure losses over a risky option and a risky option over sure gains, the opposite of typical framing biases) that has been linked to risky behavior in adolescents and is rarely observed in nondisordered adults. Experimental manipulations confirmed processing interpretations of typical framing (gist-based) and reverse-framing (verbatim-based) risk preferences. In the brain, covariation with criminal and noncriminal risk-taking was observed predominantly when subjects made reverse-framing choices. Noncriminal risk-taking behavior was associated with emotional reactivity (amygdala) and reward motivation (striatal) areas, whereas criminal behavior was associated with greater activation in temporal and parietal cortices, their junction, and insula. When subjects made more developmentally typical framing choices, reflecting non-preferred gist processing, activation in dorsolateral prefrontal cortex covaried with criminal risk-taking, which may reflect cognitive effort to process gist while inhibiting preferred verbatim processin

    How to Use the Changing Components of the Corporate Annual Report

    Get PDF
    The amount of information required in a corporate annual report continues to increase. Most recently, additional reporting requirements brought about by the Sarbanes-Oxley Act of 2002 (SOA), the Public Company Accounting Oversight Board (PCAOB) and the Securities and Exchange Commission (SEC) increase the number of component reports that must be included in the annual report package. Lenders need to be familiar with the additional information that these new components provide. Therefore, this article summarizes the required component reports, discusses the information conveyed in each report and gives some examples of the types of significant new information that can be obtained

    The Changing Components of the Corporate Annual Report: An Update

    Get PDF
    Recent regulatory changes affect not only the content of annual reports but also the population of companies that are required to comply with these reporting regulations. Lenders need to stay abreast of the information provided in corporate reporting packages. This article provides an update on regulatory changes and discusses how these changes affect the information that can be found in corporate annual reports
    • 

    corecore