A Minimally-Invasive Procedure for Sexing Young Zebra Finches

Zebra finches have been widely used to study neurobiology underlying vocal development. Because only male zebra finches learn song, efficient developmental use of these animals requires early determination of sex at ages that precede maturation of secondary sex characteristics. We have developed a sex determination method that combines a forensics method of genomic DNA isolation (from very small blood samples) with PCR amplification from Z and W sex chromosomes (males are ZZ, females ZW). This combination results in a minimally-invasive yet highly reliable and convenient genotyping method. Originally published Journal of Neuroscience Methods, Vol. 164, No. 1, Aug 200

Sergeant, Jean-Claude. L’anglais du journalisme : comprendre et traduire

This 215-page manual has been written for the benefit of journalists, students of journalism and students of English who have to read, analyse and translate the written press in English. Among Jean-Claude Sergeant’s many objectives, the first is to pass on the know-how required by any reader trying to read and understand a press article in English. Given the many subtle cultural and linguistic references that pose a challenge to the non-native speaker, the author presents the different tools ..

Suspended tensegrity:the anthropomorphic machine

The paper presents a suspended tensegrity "cloud" structure as an interactive art installation with computer vision. Actuated by 12 pneumatic rubber muscles, the research discusses the design, engineering and fabrication challenges of a dynamic tensegrity "cloud". Through material testing and physical prototyping processes, the design workflow enables a cross-disciplinary approach to the problems with feedback and an iterative static analysis approach. The project demonstrates a cross-disciplinary design collaboration between artists, architects, engineers, and the fabricator towards refinement in the engineering of dynamic structures. Using a pneumatic actuation system combined with tensegrity structures, the project demonstrated a method to develop active, controlled, deployable and form-changing envelopes and structures on a larger scale

Global Finance and Environmental Politics:

Summary This article outlines how insurance companies have so far responded to climate change. Such change threatens the viability of much of their business, by disrupting the actuarial data on which insurance risks are calculated. At the same time, insurance companies are an important component of global finance, and thus their political?economic power has led many observers to suggest that their involvement in climate politics is encouraging from an environmentalist point of view. The article critically analyses whether such optimism is justified

Dynamics of superconducting nanowires shunted with an external resistor

We present the first study of superconducting nanowires shunted with an external resistor, geared towards understanding and controlling coherence and dissipation in nanowires. The dynamics is probed by measuring the evolution of the V-I characteristics and the distributions of switching and retrapping currents upon varying the shunt resistor and temperature. Theoretical analysis of the experiments indicates that as the value of the shunt resistance is decreased, the dynamics turns more coherent presumably due to stabilization of phase-slip centers in the wire and furthermore the switching current approaches the Bardeen's prediction for equilibrium depairing current. By a detailed comparison between theory and experimental, we make headway into identifying regimes in which the quasi-one-dimensional wire can effectively be described by a zero-dimensional circuit model analogous to the RCSJ (resistively and capacitively shunted Josephson junction) model of Stewart and McCumber. Besides its fundamental significance, our study has implications for a range of promising technological applications.Comment: 15 pages, 14 figure

Thermal Infrared MMTAO Observations of the HR 8799 Planetary System

We present direct imaging observations at wavelengths of 3.3, 3.8 (L',band), and 4.8 (M band) microns, for the planetary system surrounding HR 8799. All three planets are detected at L'. The c and d component are detected at 3.3 microns, and upper limits are derived from the M band observations. These observations provide useful constraints on warm giant planet atmospheres. We discuss the current age constraints on the HR 8799 system, and show that several potential co-eval objects can be excluded from being co-moving with the star. Comparison of the photometry is made to models for giant planet atmospheres. Models which include non-equilibrium chemistry provide a reasonable match to the colors of c and d. From the observed colors in the thermal infrared we estimate T_eff < 960 K for b, and T_eff=1300 and 1170 K for c and d, respectively. This provides an independent check on the effective temperatures and thus masses of the objects from the Marois 2008 results.Comment: 16 pages, 6 figures, accepted to Ap

Ultracool Field Brown Dwarf Candidates Selected at 4.5 microns

We have identified a sample of cool field brown dwarf candidates using IRAC data from the Spitzer Deep, Wide-Field Survey (SDWFS). The candidates were selected from 400,000 SDWFS sources with [4.5] <= 18.5 mag and required to have [3.6]-[4.5] >= 1.5 and [4.5] - [8.0] <= 2.0 on the Vega system. The first color requirement selects objects redder than all but a handful of presently known brown dwarfs with spectral classes later than T7, while the second eliminates 14 probable reddened AGN. Optical detection of 4 of the remaining 18 sources implies they are likely also AGN, leaving 14 brown dwarf candidates. For two of the brightest candidates (SDWFS J143524.44+335334.6 and SDWFS J143222.82+323746.5), the spectral energy distributions including near-infrared detections suggest a spectral class of ~ T8. The proper motion is < 0.25 "/yr, consistent with expectations for a luminosity inferred distance of >70 pc. The reddest brown dwarf candidate (SDWFS J143356.62+351849.2) has [3.6] - [4.5]=2.24 and H - [4.5] > 5.7, redder than any published brown dwarf in these colors, and may be the first example of the elusive Y-dwarf spectral class. Models from Burrows et al. (2003) predict larger numbers of cool brown dwarfs should be found for a Chabrier (2003) mass function. Suppressing the model [4.5] flux by a factor of two, as indicated by previous work, brings the Burrows models and observations into reasonable agreement. The recently launched Wide-field Infrared Survey Explorer (WISE) will probe a volume ~40x larger and should find hundreds of brown dwarfs cooler than T7.Comment: 13 pages, 6 figures, accepted for publication in the June 2010 issue of The Astronomical Journa

Using optically-pumped magnetometers to measure magnetoencephalographic signals in the human cerebellum

KEY POINTS: The application of conventional cryogenic magnetoencephalography (MEG) to the study of cerebellar functions is highly limited because typical cryogenic sensor arrays are far away from the cerebellum and naturalistic movement is not allowed in the recording. A new generation of MEG using optically pumped magnetometers (OPMs) that can be worn on the head during movement has opened up an opportunity to image the cerebellar electrophysiological activity non-invasively. We use OPMs to record human cerebellar MEG signals elicited by air-puff stimulation to the eye. We demonstrate robust responses in the cerebellum. OPMs pave the way for studying the neurophysiology of the human cerebellum. ABSTRACT: We test the feasibility of an optically pumped magnetometer-based magnetoencephalographic (OP-MEG) system for the measurement of human cerebellar activity. This is to our knowledge the first study investigating the human cerebellar electrophysiology using optically pumped magnetometers. As a proof of principle, we use an air-puff stimulus to the eyeball in order to elicit cerebellar activity that is well characterized in non-human models. In three subjects, we observe an evoked component at approx. 50 ms post-stimulus, followed by a second component at approx. 85-115 ms post-stimulus. Source inversion localizes both components in the cerebellum, while control experiments exclude potential sources elsewhere. We also assess the induced oscillations, with time-frequency decompositions, and identify additional sources in the occipital lobe, a region expected to be active in our paradigm, and in the neck muscles. Neither of these contributes to the stimulus-evoked responses at 50-115 ms. We conclude that OP-MEG technology offers a promising way to advance the understanding of the information processing mechanisms in the human cerebellum

Data?driven model optimization for optically pumped magnetometer sensor arrays

© 2019 The Authors. Human Brain Mapping published by Wiley Periodicals, Inc. Optically pumped magnetometers (OPMs) have reached sensitivity levels that make them viable portable alternatives to traditional superconducting technology for magnetoencephalography (MEG). OPMs do not require cryogenic cooling and can therefore be placed directly on the scalp surface. Unlike cryogenic systems, based on a well-characterised fixed arrays essentially linear in applied flux, OPM devices, based on different physical principles, present new modelling challenges. Here, we outline an empirical Bayesian framework that can be used to compare between and optimise sensor arrays. We perturb the sensor geometry (via simulation) and with analytic model comparison methods estimate the true sensor geometry. The width of these perturbation curves allows us to compare different MEG systems. We test this technique using simulated and real data from SQUID and OPM recordings using head-casts and scanner-casts. Finally, we show that given knowledge of underlying brain anatomy, it is possible to estimate the true sensor geometry from the OPM data themselves using a model comparison framework. This implies that the requirement for accurate knowledge of the sensor positions and orientations a priori may be relaxed. As this procedure uses the cortical manifold as spatial support there is no co-registration procedure or reliance on scalp landmarks

MinION Analysis and Reference Consortium: Phase 1 data release and analysis

The advent of a miniaturized DNA sequencing device with a high-throughput contextual sequencing capability embodies the next generation of large scale sequencing tools. The MinION™ Access Programme (MAP) was initiated by Oxford Nanopore Technologies™ in April 2014, giving public access to their USB-attached miniature sequencing device. The MinION Analysis and Reference Consortium (MARC) was formed by a subset of MAP participants, with the aim of evaluating and providing standard protocols and reference data to the community. Envisaged as a multi-phased project, this study provides the global community with the Phase 1 data from MARC, where the reproducibility of the performance of the MinION was evaluated at multiple sites. Five laboratories on two continents generated data using a control strain of Escherichia coli K-12, preparing and sequencing samples according to a revised ONT protocol. Here, we provide the details of the protocol used, along with a preliminary analysis of the characteristics of typical runs including the consistency, rate, volume and quality of data produced. Further analysis of the Phase 1 data presented here, and additional experiments in Phase 2 of E. coli from MARC are already underway to identify ways to improve and enhance MinION performance