Vibrational States of Glassy and Crystalline Orthotherphenyl

Low-frequency vibrations of glassy and crystalline orthoterphenyl are studied by means of neutron scattering. Phonon dispersions are measured along the main axes of a single crystal, and the corresponding longitudinal and transversal sound velocities are obtained. For glassy and polycrystalline samples, a density of vibrational states is determined and cross-checked against other dynamic observables. In the crystal, low-lying zone-boundary modes lead to an excess over the Debye density of states. In the glass, the boson peak is located at even lower frequencies. With increasing temperature, both glass and crystal show anharmonicity.Comment: 7 pages of LaTeX (svjour), 2 tables, 10 figures accepted in Eur. Phys. J.

Pressure dependence of diffusion in simple glasses and supercooled liquids

Using molecular dynamics simulation, we have calculated the pressure dependence of the diffusion constant in a binary Lennard-Jones Glass. We observe four temperature regimes. The apparent activation volume drops from high values in the hot liquid to a plateau value. Near the critical temperature of the mode coupling theory it rises steeply, but in the glassy state we find again small values, similar to the ones in the liquid. The peak of the activation volume at the critical temperature is in agreement with the prediction of mode coupling theory

Modeling Speech Disfluency to Predict Conceptual Misalignment in Speech Survey Interfaces

Computer-based interviewing systems could use models of respondent disfluency behaviors to predict a need for clarification of terms in survey questions. We compare simulated speech interfaces that use two such models - a generic model and a stereotyped model that distinguishes between the speech of younger and older speakers - to several non-modeling speech interfaces in a task where respondents provided answers to survey questions from fictional scenarios. Our modeling procedure found that the best predictor of conceptual misalignment was a critical Goldilocks range for response latency, outside of which responses are more likely to be conceptually misaligned. Different Goldilocks ranges are effective for younger and older speakers

What about their performance do free jazz improvisers agree upon? A case study

When musicians improvise freely together—not following any sort of script, predetermined harmonic structure, or “referent”—to what extent do they understand what they are doing in the same way as each other? And to what extent is their understanding privileged relative to outside listeners with similar levels of performing experience in free improvisation? In this exploratory case study, a saxophonist and a pianist of international renown who knew each other's work but who had never performed together before were recorded while improvising freely for 40 min. Immediately afterwards the performers were interviewed separately about the just-completed improvisation, first from memory and then while listening to two 5 min excerpts of the recording in order to prompt specific and detailed commentary. Two commenting listeners from the same performance community (a saxophonist and drummer) listened to, and were interviewed about, these excerpts. Some months later, all four participants rated the extent to which they endorsed 302 statements that had been extracted from the four interviews and anonymized. The findings demonstrate that these free jazz improvisers characterized the improvisation quite differently, selecting different moments to comment about and with little overlap in the content of their characterizations. The performers were not more likely to endorse statements by their performing partner than by a commenting listener from the same performance community, and their patterns of agreement with each other (endorsing or dissenting with statements) across multiple ratings—their interrater reliability as measured with Cohen's kappa—was only moderate, and not consistently higher than their agreement with the commenting listeners. These performers were more likely to endorse statements about performers' thoughts and actions than statements about the music itself, and more likely to endorse evaluatively positive than negative statements. But these kinds of statements were polarizing; the performers were more likely to agree with each other in their ratings of statements about the music itself and negative statements. As in Schober and Spiro (2014), the evidence supports a view that fully shared understanding is not needed for joint improvisation by professional musicians in this genre and that performing partners can agree with an outside listener more than with each other

Chaos control in random Boolean networks by reducing mean damage percolation rate

Chaos control in Random Boolean networks is implemented by freezing part of the network to drive it from chaotic to ordered phase. However, controlled nodes are only viewed as passive blocks to prevent perturbation spread. This paper proposes a new control method in which controlled nodes can exert an active impact on the network. Controlled nodes and frozen values are deliberately selected according to the information of connection and Boolean functions. Simulation results show that the number of nodes needed to achieve control is largely reduced compared to previous method. Theoretical analysis is also given to estimate the least fraction of nodes needed to achieve control.Comment: 10 pages, 2 figure

Survey-based naming conventions for use in OBO Foundry ontology development

A wide variety of ontologies relevant to the biological and medical domains are available through the OBO Foundry portal, and their number is growing rapidly. Integration of these ontologies, while requiring considerable effort, is extremely desirable. However, heterogeneities in format and style pose serious obstacles to such integration. In particular, inconsistencies in naming conventions can impair the readability and navigability of ontology class hierarchies, and hinder their alignment and integration. While other sources of diversity are tremendously complex and challenging, agreeing a set of common naming conventions is an achievable goal, particularly if those conventions are based on lessons drawn from pooled practical experience and surveys of community opinion. We summarize a review of existing naming conventions and highlight certain disadvantages with respect to general applicability in the biological domain. We also present the results of a survey carried out to establish which naming conventions are currently employed by OBO Foundry ontologies and to determine what their special requirements regarding the naming of entities might be. Lastly, we propose an initial set of typographic, syntactic and semantic conventions for labelling classes in OBO Foundry ontologies. Adherence to common naming conventions is more than just a matter of aesthetics. Such conventions provide guidance to ontology creators, help developers avoid flaws and inaccuracies when editing, and especially when interlinking, ontologies. Common naming conventions will also assist consumers of ontologies to more readily understand what meanings were intended by the authors of ontologies used in annotating bodies of data

When Do Misunderstandings Matter? Evidence From Survey Interviews About Smoking

This paper examines when conceptual misalignments in dialog lead to consequential miscommunication. Two studies explore misunderstanding in survey interviews of the sort conducted by governments and social scientists, where mismeasurement can have real social costs. In 131 interviews about tobacco use, misalignment between respondents’ and researchers’ conceptions of ordinary expressions like “smoking” and “every day” was quantified by probing respondents’ interpretations of survey terms and re‐administering the survey questionnaire with standard definitions after the interview. Respondents’ interpretations were surprisingly variable, and in many cases they did not match the conceptions that researchers intended them to use. More often than one might expect, this conceptual variability was consequential, leading to answers (and, in principle, to estimates of the prevalence of smoking and related attributes in the population) that would have been different had conceptualizations been aligned; for example, fully 12% of respondents gave a different answer about having smoked 100 cigarettes in their entire life when later given a standard definition. In other cases misaligned interpretations did not lead to miscommunication, in that the differences would not have led to different survey responses. Although clarification of survey terms during the interview sometimes improved conceptual alignment, this was not guaranteed; in this corpus some needed attempts at clarification were never made, some attempts did not succeed, and some seemed to make understanding worse. The findings suggest that conceptual misalignments may be more frequent in ordinary conversation than interlocutors know, and that attempts to detect and clarify them may not always work. They also suggest that at least some unresolved misunderstandings do not matter in the sense that they do not change the outcome of the communication—in this case, the survey estimates.Schober et al. describe two studies on how survey interview respondents misunderstand interview questions. After answering a survey, participants are given standardized definitions of the questions they have just answered. Even apparently simple questions such as “Have you smoked more than 100 cigarettes?” are interpreted very differently by participants. Moreover, clarifying the meaning of the definitions with the interviewer does not always help resolve the miscommunication.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143616/1/tops12330_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/143616/2/tops12330.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/143616/3/tops12330-sup-0003-AppendixS3.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/143616/4/tops12330-sup-0002-AppendixS2.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/143616/5/tops12330-sup-0005-TableS2.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/143616/6/tops12330-sup-0001-AppendixS1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/143616/7/tops12330-sup-0004-TableS1.pd

Wavenumber dependence of structural alpha relaxation in a molecular liquid

Structural alpha relaxation in liquid orthoterphenyl is studied by means of coherent neutron time-of-flight and backscattering spectroscopy over a large temperature range. Not only amplitude and relaxation time but also the spectral line shape show a significant variation with wavenumber. As expected from mode coupling theory, these variations are correlated with the static structure factor. Even far above the melting point, alpha relaxation remains non-exponential.Comment: 6 pages of LaTeX, 4 figure