Technical communication. Perspectives for the Eighties, part 2

The importance of technical writing as a separate discipline is suggested. Some specific areas addressed were: technical writing skills industry needs, definitions of technical writing, the hows and whys of inhouse writing, and the nature of the composing process in technical comunication

Technical Communication: Perspectives for the Eighties, Part 1. Proceedings of the Technical Communications Sessions at the 32Nd Annual Meeting of the Conference on College Composition and Communication

Proceeding of the technical communication sessions at the 32nd annual meeting of the Conference on College Composition and Communication held in Dallas, Texas, March 26-28, 1981 are summarized. The proceeding suggest that technical communication has become an important subfield and is becoming an intrinsic part of many undergraduate curricula. Technical communication as a separate discipline, however, is relatively new. For that reason, proceedings that can make current research available as quickly as possible are suggested for preparation. The following topics were addressed: (1) a history and definition of technical writing, (2) the case method is technical communication (3) teaching technical writing (4) oral communication and rhetorical theory, and (5) new approaches in and practical applications of technical writing

Search for hidden-photon dark matter with the FUNK experiment

Many extensions of the Standard Model of particle physics predict a parallel sector of a new U(1) symmetry, giving rise to hidden photons. These hidden photons are candidate particles for cold dark matter. They are expected to kinetically mix with regular photons, which leads to a tiny oscillating electric-field component accompanying dark matter particles. A conducting surface can convert such dark matter particles into photons which are emitted almost perpendicularly to the surface. The corresponding photon frequency follows from the mass of the hidden photons. In this contribution we present a preliminary result on a hidden photon search in the visible and near-UV wavelength range that was done with a large, 14 m2 spherical metallic mirror and discuss future dark matter searches in the eV and sub-eV range by application of different detectors for electromagnetic radiation.Comment: Contribution to the 35th International Cosmic Ray Conference ICRC2017, 10 to 20 July, 2017, Bexco, Busan, Korea. arXiv admin note: text overlap with arXiv:1711.0296

Machine learning for automatic prediction of the quality of electrophysiological recordings

The quality of electrophysiological recordings varies a lot due to technical and biological variability and neuroscientists inevitably have to select “good” recordings for further analyses. This procedure is time-consuming and prone to selection biases. Here, we investigate replacing human decisions by a machine learning approach. We define 16 features, such as spike height and width, select the most informative ones using a wrapper method and train a classifier to reproduce the judgement of one of our expert electrophysiologists. Generalisation performance is then assessed on unseen data, classified by the same or by another expert. We observe that the learning machine can be equally, if not more, consistent in its judgements as individual experts amongst each other. Best performance is achieved for a limited number of informative features; the optimal feature set being different from one data set to another. With 80–90% of correct judgements, the performance of the system is very promising within the data sets of each expert but judgments are less reliable when it is used across sets of recordings from different experts. We conclude that the proposed approach is relevant to the selection of electrophysiological recordings, provided parameters are adjusted to different types of experiments and to individual experimenters

Third Level Trigger for the Fluorescence Telescopes of the Pierre Auger Observatory

The trigger system for the Auger fluorescence telescopes is implemented in hard- and software for an efficient selection of fluorescence light tracks induced by high-energy extensive air showers. The algorithm of the third stage uses the multiplicity signal of the hardware for fast rejection of lightning events with above 99% efficiency. In a second step direct muon hits in the camera and random triggers are rejected by analyzing the space-time correlation of the pixels. The trigger algorithm was tested with measured and simulated showers and implemented in the electronics of the fluorescence telescopes. A comparison to a prototype trigger without multiplicity shows the superiority of this approach, e.g. the false rejection rate is a factor 10 lower.Comment: 8 pages, 7 figures, to be published in NIM A; 1 typo correcte

BLUF Domain Function Does Not Require a Metastable Radical Intermediate State

BLUF (blue light using flavin) domain proteins are an important family of blue light-sensing proteins which control a wide variety of functions in cells. The primary light-activated step in the BLUF domain is not yet established. A number of experimental and theoretical studies points to a role for photoinduced electron transfer (PET) between a highly conserved tyrosine and the flavin chromophore to form a radical intermediate state. Here we investigate the role of PET in three different BLUF proteins, using ultrafast broadband transient infrared spectroscopy. We characterize and identify infrared active marker modes for excited and ground state species and use them to record photochemical dynamics in the proteins. We also generate mutants which unambiguously show PET and, through isotope labeling of the protein and the chromophore, are able to assign modes characteristic of both flavin and protein radical states. We find that these radical intermediates are not observed in two of the three BLUF domains studied, casting doubt on the importance of the formation of a population of radical intermediates in the BLUF photocycle. Further, unnatural amino acid mutagenesis is used to replace the conserved tyrosine with fluorotyrosines, thus modifying the driving force for the proposed electron transfer reaction; the rate changes observed are also not consistent with a PET mechanism. Thus, while intermediates of PET reactions can be observed in BLUF proteins they are not correlated with photoactivity, suggesting that radical intermediates are not central to their operation. Alternative nonradical pathways including a keto–enol tautomerization induced by electronic excitation of the flavin ring are considered

Joint Elastic Side-Scattering Lidar and Raman Lidar Measurements of Aerosol Optical Properties in South East Colorado

We describe an experiment, located in south-east Colorado, USA, that measured aerosol optical depth profiles using two Lidar techniques. Two independent detectors measured scattered light from a vertical UV laser beam. One detector, located at the laser site, measured light via the inelastic Raman backscattering process. This is a common method used in atmospheric science for measuring aerosol optical depth profiles. The other detector, located approximately 40km distant, viewed the laser beam from the side. This detector featured a 3.5m2 mirror and measured elastically scattered light in a bistatic Lidar configuration following the method used at the Pierre Auger cosmic ray observatory. The goal of this experiment was to assess and improve methods to measure atmospheric clarity, specifically aerosol optical depth profiles, for cosmic ray UV fluorescence detectors that use the atmosphere as a giant calorimeter. The experiment collected data from September 2010 to July 2011 under varying conditions of aerosol loading. We describe the instruments and techniques and compare the aerosol optical depth profiles measured by the Raman and bistatic Lidar detectors.Comment: 34 pages, 16 figure

First results of the air shower experiment KASCADE

The main goals of the KASCADE (KArlsruhe Shower Core and Array DEtector) experiment are the determination of the energy spectrum and elemental composition of the charged cosmic rays in the energy range around the knee at ca. 5 PeV. Due to the large number of measured observables per single shower a variety of different approaches are applied to the data, preferably on an event-by-event basis. First results are presented and the influence of the high-energy interaction models underlying the analyses is discussed.Comment: 3 pages, 3 figures included, to appear in the TAUP 99 Proceedings, Nucl. Phys. B (Proc. Suppl.), ed. by M. Froissart, J. Dumarchez and D. Vignau