A Bayesian Reflection on Surfaces

The topic of this paper is a novel Bayesian continuous-basis field representation and inference framework. Within this paper several problems are solved: The maximally informative inference of continuous-basis fields, that is where the basis for the field is itself a continuous object and not representable in a finite manner; the tradeoff between accuracy of representation in terms of information learned, and memory or storage capacity in bits; the approximation of probability distributions so that a maximal amount of information about the object being inferred is preserved; an information theoretic justification for multigrid methodology. The maximally informative field inference framework is described in full generality and denoted the Generalized Kalman Filter. The Generalized Kalman Filter allows the update of field knowledge from previous knowledge at any scale, and new data, to new knowledge at any other scale. An application example instance, the inference of continuous surfaces from measurements (for example, camera image data), is presented.Comment: 34 pages, 1 figure, abbreviated versions presented: Bayesian Statistics, Valencia, Spain, 1998; Maximum Entropy and Bayesian Methods, Garching, Germany, 199

Engineering Valence Band Dispersion for High Mobility p-Type Semiconductors

The paucity of high performance transparent p-type semiconductors has been a stumbling block for the electronics industry for decades, effectively hindering the route to efficient transparent devices based on p–n junctions. Cu-based oxides and subsequently Cu-based oxychalcogenides have been heavily studied as affordable, earth-abundant p-type transparent semiconductors, where the mixing of the Cu 3d states with the chalcogenide 2p states at the top of the valence band encourages increased valence band dispersion. In this article, we extend this mixing concept further, by utilizing quantum chemistry techniques to investigate ternary copper phosphides as potential high mobility p-type materials. We use hybrid density functional theory to examine a family of phosphides, namely, MCuP (M = Mg, Ca, Sr, Ba) which all possess extremely disperse valence band maxima, comparable to the dispersion of excellent industry standard n-type transparent conducting oxides. As a proof of concept, we synthesized and characterized powders of CaCuP, showing that they display high levels of p-type conductivity, without any external acceptor dopant. Lastly, we discuss the role of Cu-coordination in promoting valence band dispersion and provide design principles for producing degenerate p-type materials

Thermal development of latent fingermarks on porous surfaces-Further observations and refinements

In a further study of the thermal development of fingermarks on paper and similar surfaces, it is demonstrated that direct contact heating of the substrate using coated or ceramic surfaces at temperatures in excess of 230 °C produces results superior to those obtained using hot air. Fingermarks can also be developed in this way on other cellulose-based substrates such as wood and cotton fabric, though ridge detail is difficult to obtain in the latter case. Fluorescence spectroscopy indicates that the phenomena observed during the thermal development of fingermarks can be reproduced simply by heating untreated white copy paper or filter paper, or these papers treated with solutions of sodium chloride or alanine. There is no evidence to suggest that the observed fluorescence of fingermarks heated on paper is due to a reaction of fingermark constituents on or with the paper. Instead, we maintain that the ridge contrast observed first as fluorescence, and later as brown charring, is simply an acceleration of the thermal degradation of the paper. Thermal degradation of cellulose, a major constituent of paper and wood, is known to give rise to a fluorescent product if sufficient oxygen is available [1-5]. However, the absence of atmospheric oxygen has only a slight effect on the thermal development of fingermarks, indicating that there is sufficient oxygen already present in paper to allow the formation of the fluorescent and charred products. In a depletion study comparing thermal development of fingermarks on paper with development using ninhydrin, the thermal technique was found to be as sensitive as ninhydrin for six out of seven donors. When thermal development was used in sequence with ninhydrin and DFO, it was found that only fingermarks that had been developed to the fluorescent stage (a few seconds of heating) could subsequently be developed with the other reagents. In the reverse sequence, no useful further development was noted for fingermarks that were treated thermally after having been developed with ninhydrin or DFO. Aged fingermarks, including marks from 1-year-old university examination papers were successfully developed using the thermal technique. © 2010 Elsevier Ireland Ltd

The acoustic space of pain: cries as indicators of distress recovering dynamics in preverbal infants

Crying is a vital built-in survival mechanism for the Human baby. Yet both the information carried by cries and the factors driving the perception and reaction of adult listeners remain under-investigated. Here, we contrasted the relevance of psychoacoustic vs. acoustic evaluation for the assessment of distress levels in babies' cries recorded during baths and during an immunization event. Parents asked to rate the level of distress experienced by babies from listening to their cries attributed lower pain ratings to mild discomfort (bath) than to distress (vaccination) cries but failed to discriminate between different putative levels of pain experienced during different vaccination sequences. In contrast, vocal "roughness", a composite acoustic factor characterising the level of aperiodicity of the cries, not only differed between mild discomfort and distress cries but also between the levels of pain experienced during the different vaccination sequences. These observations suggest that acoustic analyses are more powerful than psychoacoustic evaluations for discriminating distress levels in babies’ cries, and opens the way for the design of a tool based on the acoustics of cries for assessing and monitoring pain levels in preverbal infants

The Fusion Loops of the Initial Prefusion Conformation of Herpes Simplex Virus 1 Fusion Protein Point Toward the Membrane

All enveloped viruses, including herpesviruses, must fuse their envelope with the host membrane to deliver their genomes into target cells, making this essential step subject to interference by antibodies and drugs. Viral fusion is mediated by a viral surface protein that transits from an initial prefusion conformation to a final postfusion conformation. Strikingly, the prefusion conformation of the herpesvirus fusion protein, gB, is poorly understood. Herpes simplex virus (HSV), a model system for herpesviruses, causes diseases ranging from mild skin lesions to serious encephalitis and neonatal infections. Using cryo-electron tomography and subtomogram averaging, we have characterized the structure of the prefusion conformation and fusion intermediates of HSV-1 gB. To this end, we have set up a system that generates microvesicles displaying full-length gB on their envelope. We confirmed proper folding of gB by nondenaturing electrophoresis-Western blotting with a panel of monoclonal antibodies (MAbs) covering all gB domains. To elucidate the arrangement of gB domains, we labeled them by using (i) mutagenesis to insert fluorescent proteins at specific positions, (ii) coexpression of gB with Fabs for a neutralizing MAb with known binding sites, and (iii) incubation of gB with an antibody directed against the fusion loops. Our results show that gB starts in a compact prefusion conformation with the fusion loops pointing toward the viral membrane and suggest, for the first time, a model for gB’s conformational rearrangements during fusion. These experiments further illustrate how neutralizing antibodies can interfere with the essential gB structural transitions that mediate viral entry and therefore infectivity