Interferon as a macrophage activating factor. I. Enhancement of cytotoxicity by fresh and matured human monocytes in the absence of other soluble signals

The cytolytic activity ofhuman peripheral blood monocytes in vitro against K-562 human leukaemic target cells was stimulated by human fibroblast (fi-) and leucocyte (a-) interferon (IFN). Stimulation was by up to several times the corresponding control activity, and was observed with freshly isolated monocytes, and with monocytes cultured for various periods up to 10 days. The cytolytic activity of untreated monocytes was detectable at very low effector: target ratios ( < 5: 1), and fell between days 1 and 4 in culture, normally rising again towards the initial activity at day 8; this pattern was also observed when IFN was present continuously, although the activities were then always higher than in the corresponding control cells. Cytolysis showed a lag of about 6 hr, in contrast to that by natural killer (NK) cells, and was routinely measured over 24 hr. The course of stimulation by IFN and its dose-response were studied. Stimulation required the presence of IFN for at least 24 hr, and was maximal with between 1,000 and 10,000 units of IFN/ml. When IFN containing media were removed and replaced with control media, the monocyte activity remained stimulated for at least 4 days. Stimulation by fl-IFN was blocked by a specific antibody to fl-IFN, under conditions in which assayable IFN activity was also neutralized. Several control experiments indicated that the action of IFN was on the monocytes and not on the target cells. The morphological maturation of monocytes was retarded by IFN, even in cultures containing up to 50% serum. The effectiveness of fibroblast IFN indicated that stimulation could not be attributed to the lymphokines which might contaminate a-IFN. The action of IFN did not require simultaneous or antecedent in vitro stimulation by endotoxin. This was indicated both by serum free experiments, and also by others in which polymixin B was used to complex with and render unavailable any endotoxin present. Endotoxin showed an independent stimulatory effect, which could be prevented by polymixin

Relationships between generated musical structure, performers’ physiological arousal and listener perceptions in solo piano improvisation

What musical structures do improvisers produce, and how do these relate to their physiological arousal while performing and to listener perceptions? Nine professional improvisers performed both structured and free improvisations. We hypothesised that increases in performers’ arousal and attention during structural transitions would be reflected by changes in skin conductance. Consistent with the hypothesis, skin conductance changed particularly around transitions. Improvisers then listened to their improvisations, continuously rating musical change. Fourteen non-musicians also rated change, and separately rated perceptions of affect. Their perceptions related to structural parameters, though these were less influenced by musical features than those of the performers

Modeling Perceptions of Valence in Diverse Music: Roles of Acoustic Features, Agency and Individual Variation

We investigate the roles of the acoustic parameters intensity and spectral flatness in the modeling of continuously measured perceptions of affect in nine diverse musical extracts. The extract sources range from Australian Aboriginal and Balinese music, to classical music from Mozart to minimalism and Xenakis; and include jazz, ambient, drum n' bass and performance text. We particularly assess whether modeling perceptions of the valence expressed by the music, generally modeled less well than the affective dimension of arousal, can be enhanced by inclusion of perceptions of change in the sound, human agency, musical segmentation, and random effects across participants, as model components. We confirm each of these expectations, and provide indications that perceived change in the music may eventually be subsumed adequately under its components such as acoustic features and agency. We find that participants vary substantially in the predictors useful for modeling their responses (judged by the random effects components of mixed effects cross-sectional time series analyses). But we also find that pieces do too, while yet sharing sufficient features that a single common model of the responses to all nine pieces has competitive precision

Linking Melodic Expectation to Expressive Performance Timing and Perceived Musical Tension

This article may not exactly replicate the final version published in the APA journal. It is not the copy of record

Synchronization can influence trust following virtual interaction.

Synchronization has recently received attention as a form of interpersonal interaction that may affect the affiliative relationships of those engaged in it. While there is evidence to suggest that synchronized movements lead to increased affiliative behavior (Hove and Risen, 2009; Valdesolo and DeSteno, 2011; Wiltermuth and Heath, 2009), the influence of other interpersonal cues has yet to be fully controlled. The current study controls for these features by using computer algorithms to replace human partners. By removing genuine interpersonal interaction, it also tests whether sounds alone can influence affiliative relationships, when it appears that another human agent has triggered those sounds. Results suggest that subjective experience of synchrony had a positive effect on a measure of trust, but task success was a similarly good predictor. An objective measure of synchrony was only related to trust in conditions where participants were instructed to move at the same time as stimuli

Dual-gated bilayer graphene hot electron bolometer

Detection of infrared light is central to diverse applications in security, medicine, astronomy, materials science, and biology. Often different materials and detection mechanisms are employed to optimize performance in different spectral ranges. Graphene is a unique material with strong, nearly frequency-independent light-matter interaction from far infrared to ultraviolet, with potential for broadband photonics applications. Moreover, graphene's small electron-phonon coupling suggests that hot-electron effects may be exploited at relatively high temperatures for fast and highly sensitive detectors in which light energy heats only the small-specific-heat electronic system. Here we demonstrate such a hot-electron bolometer using bilayer graphene that is dual-gated to create a tunable bandgap and electron-temperature-dependent conductivity. The measured large electron-phonon heat resistance is in good agreement with theoretical estimates in magnitude and temperature dependence, and enables our graphene bolometer operating at a temperature of 5 K to have a low noise equivalent power (33 fW/Hz1/2). We employ a pump-probe technique to directly measure the intrinsic speed of our device, >1 GHz at 10 K.Comment: 5 figure

Microscopic Polarization in Bilayer Graphene

Bilayer graphene has drawn significant attention due to the opening of a band gap in its low energy electronic spectrum, which offers a promising route to electronic applications. The gap can be either tunable through an external electric field or spontaneously formed through an interaction-induced symmetry breaking. Our scanning tunneling measurements reveal the microscopic nature of the bilayer gap to be very different from what is observed in previous macroscopic measurements or expected from current theoretical models. The potential difference between the layers, which is proportional to charge imbalance and determines the gap value, shows strong dependence on the disorder potential, varying spatially in both magnitude and sign on a microscopic level. Furthermore, the gap does not vanish at small charge densities. Additional interaction-induced effects are observed in a magnetic field with the opening of a subgap when the zero orbital Landau level is placed at the Fermi energy

Electron quantum metamaterials in van der Waals heterostructures

In recent decades, scientists have developed the means to engineer synthetic periodic arrays with feature sizes below the wavelength of light. When such features are appropriately structured, electromagnetic radiation can be manipulated in unusual ways, resulting in optical metamaterials whose function is directly controlled through nanoscale structure. Nature, too, has adopted such techniques -- for example in the unique coloring of butterfly wings -- to manipulate photons as they propagate through nanoscale periodic assemblies. In this Perspective, we highlight the intriguing potential of designer sub-electron wavelength (as well as wavelength-scale) structuring of electronic matter, which affords a new range of synthetic quantum metamaterials with unconventional responses. Driven by experimental developments in stacking atomically layered heterostructures -- e.g., mechanical pick-up/transfer assembly -- atomic scale registrations and structures can be readily tuned over distances smaller than characteristic electronic length-scales (such as electron wavelength, screening length, and electron mean free path). Yet electronic metamaterials promise far richer categories of behavior than those found in conventional optical metamaterial technologies. This is because unlike photons that scarcely interact with each other, electrons in subwavelength structured metamaterials are charged, and strongly interact. As a result, an enormous variety of emergent phenomena can be expected, and radically new classes of interacting quantum metamaterials designed

Observation of Coherent Elastic Neutrino-Nucleus Scattering

The coherent elastic scattering of neutrinos off nuclei has eluded detection for four decades, even though its predicted cross-section is the largest by far of all low-energy neutrino couplings. This mode of interaction provides new opportunities to study neutrino properties, and leads to a miniaturization of detector size, with potential technological applications. We observe this process at a 6.7-sigma confidence level, using a low-background, 14.6-kg CsI[Na] scintillator exposed to the neutrino emissions from the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory. Characteristic signatures in energy and time, predicted by the Standard Model for this process, are observed in high signal-to-background conditions. Improved constraints on non-standard neutrino interactions with quarks are derived from this initial dataset

Spectral Pitch Similarity is a Predictor of Perceived Change in Sound- as Well as Note-Based Music

Spectral pitch similarity (SPS) is a measure of the similarity between spectra of any pair of sounds. It has proved powerful in predicting perceived stability and fit of notes and chords in various tonal and microtonal instrumental contexts, that is, with discrete tones whose spectra are harmonic or close to harmonic. Here we assess the possible contribution of SPS to listeners’ continuous perceptions of change in music with fewer discrete events and with noisy or profoundly inharmonic sounds, such as electroacoustic music. Previous studies have shown that time series of perception of change in a range of music can be reasonably represented by time series models, whose predictors comprise autoregression together with series representing acoustic intensity and, usually, the timbral parameter spectral flatness. Here, we study possible roles for SPS in such models of continuous perceptions of change in a range of both instrumental (note-based) and sound-based music (generally containing more noise and fewer discrete events). In the first analysis, perceived change in three pieces of electroacoustic and one of piano music is modeled, to assess the possible contribution of (de-noised) SPS in cooperation with acoustic intensity and spectral flatness series. In the second analysis, a broad range of nine pieces is studied in relation to the wider range of distinctive spectral predictors useful in previous perceptual work, together with intensity and SPS. The second analysis uses cross-sectional (mixed-effects) time series analysis to take advantage of all the individual response series in the dataset, and to assess the possible generality of a predictive role for SPS. SPS proves to be a useful feature, making a predictive contribution distinct from other spectral parameters. Because SPS is a psychoacoustic “bottom up” feature, it may have wide applicability across both the familiar and the unfamiliar in the music to which we are exposed