Structure and Emergence of Specific Olfactory Glomeruli in the Mouse

Olfactory sensory neurons (OSNs) expressing a given odorant receptor (OR) gene project their axons to a few specific glomeruli that reside at recognizable locations in the olfactory bulb. Connecting ∼1000 populations of OSNs to the ∼1800 glomeruli of the mouse bulb poses a formidable wiring problem. Additional progress in understanding the mechanisms of neuronal connectivity is dependent on knowing how these axonal pathways are organized and how they form during development. Here we have applied a genetic approach to this problem. We have constructed by gene targeting novel strains of mice in which either all OSNs or those that express a specific OR gene, M72 or M71, also produce green fluorescent protein (GFP) or a fusion of tau with GFP. We visualized OSNs and their axons in whole mounts with two-photon laser scanning microscopy. The main conclusion we draw from the three-dimensional reconstructions is the high degree of morphological variability of mature glomeruli receiving axonal input from OR-expressing OSNs and of the pathways taken by the axons to those glomeruli. We also observe that axons of OR-expressing OSNs do not innervate nearby glomeruli in mature mice. Postnatally, a tangle of axons from M72-expressing OSNs occupies a large surface area of the bulb and coalesces abruptly into a protoglomerulus at a reproducible stage of development. These results differ in several aspects from those reported for the development of glomeruli receiving input from OSNs expressing the P2 OR, suggesting the need for a more systematic examination of OR-specific glomeruli

The Use of In-Situ Simulation to Improve Safety in the Plastic Surgery Office: A Feasibility Study

Objective: Simulation-based interventions and education can potentially contribute to safer and more effective systems of care. We utilized in-situ simulation to highlight safety issues, regulatory requirements, and assess perceptions of safety processes by the plastic surgery office staff. Methods: A high-fidelity human patient simulator was brought to an office-based plastic surgery setting to enact a half-day full-scale, multidisciplinary medical emergency. Facilitated group debriefings were conducted after each scenario with special consideration of the principles of team training, communication, crisis management, and adherence to evidence-based protocols and regulatory standards. Abbreviated AHRQ Medical Office Safety Culture Survey was completed by the participants before and after the session. Results: The in-situ simulations had a high degree of acceptance and face validity according to the participants. Areas highlighted by the simulation sessions included rapid communication, delegation of tasks, location of emergency materials, scope of practice, and logistics of transport. The participant survey indicated greater awareness of patient safety issues following participation in simulation and debriefing exercises in 3 areas (P < 0.05): the need to change processes if there is a recognized patient safety issue (100% vs 75%), openness to ideas about improving office processes (100% vs 88%), and the need to discuss ways to prevent errors from recurring (88% vs 62%). Conclusions: Issues of safety and regulatory compliance can be assessed in an office-based setting through the short-term (half-day) use of in-situ simulation with facilitated debriefing and the review of audiovisual recordings by trained facilities inspectors

GeauxDock: A novel approach for mixed-resolution ligand docking using a descriptor-based force field

© 2015 Wiley Periodicals, Inc. Molecular docking is an important component of computer-aided drug discovery. In this communication, we describe GeauxDock, a new docking approach that builds on the ideas of ligand homology modeling. GeauxDock features a descriptor-based scoring function integrating evolutionary constraints with physics-based energy terms, a mixed-resolution molecular representation of protein-ligand complexes, and an efficient Monte Carlo sampling protocol. To drive docking simulations toward experimental conformations, the scoring function was carefully optimized to produce a correlation between the total pseudoenergy and the native-likeness of binding poses. Indeed, benchmarking calculations demonstrate that GeauxDock has a strong capacity to identify near-native conformations across docking trajectories with the area under receiver operating characteristics of 0.85. By excluding closely related templates, we show that GeauxDock maintains its accuracy at lower levels of homology through the increased contribution from physics-based energy terms compensating for weak evolutionary constraints. GeauxDock is available at http://www.institute.Loni.org/lasigma/package/dock/

K2-136: A Hyades Binary Star with a Neptune-sized Planet

We report the discovery of a Neptune-size planet (Rp = 3.0 Re) in the Hyades Cluster. The host star is in a binary system, comprising a K5V star and M7/8V star with a projected separation of 40 AU. The planet orbits the primary star with an orbital period of 17.3 days and a transit duration of 3 hours. The host star is bright (V=11.2, J=9.1) and so may be a good target for precise radial velocity measurements. K2-136A c is the first Neptune-sized planet to be found orbiting in a binary system within an open cluster. The Hyades is the nearest star cluster to the Sun, has an age of 625-750 Myr, and forms one of the fundamental rungs in the distance ladder; understanding the planet population in such a well-studied cluster can help us understand and set constraints on the formation and evolution of planetary systems.Comment: 13 pages, 8 figures, 2 tables. Accepted to AAS Journal

MSIS 2000: Model Curriculum and Guidelines for Graduate Degree Programs in Information Systems

This article contains the official text of the MSIS 2000 model curriculum as approved by both the Association for Computing Machinery and the Association for Information Systems. It is presented here in its original form

Brane cosmology with a bulk scalar field

We consider ``cosmologically symmetric'' (i.e. solutions with homogeneity and isotropy along three spatial dimensions) five-dimensional spacetimes with a scalar field and a three-brane representing our universe. We write Einstein's equations in a conformal gauge, using light-cone coordinates. We obtain explicit solutions: a. assuming proportionality between the scalar field and the logarithm of the (bulk) scale factor; b. assuming separable solutions. We then discuss the cosmology in the brane nduced by these solutions.Comment: 24 pages, Latex, no figur

Cosmological perturbation spectra from SL(4,R)-invariant effective actions

We investigate four-dimensional cosmological vacuum solutions derived from an effective action invariant under global SL(n,R) transformations. We find the general solutions for linear axion field perturbations about homogeneous dilaton-moduli-vacuum solutions for an SL(4,R)-invariant action and find the spectrum of super-horizon perturbations resulting from vacuum fluctuations in a pre big bang scenario. We show that for SL(n,R)-invariant actions with n>3 there exists a regime of parameter space of non-zero measure where all the axion field spectra have positive spectral tilt, as required if light axion fields are to provide a seed for anisotropies in the microwave background and large-scale structure in the universe.Comment: 8 pages, 3 figures, revtex plus epsf, minor typos corrected, version to appear in Physical Review

The camera of the fifth H.E.S.S. telescope. Part I: System description

In July 2012, as the four ground-based gamma-ray telescopes of the H.E.S.S. (High Energy Stereoscopic System) array reached their tenth year of operation in Khomas Highlands, Namibia, a fifth telescope took its first data as part of the system. This new Cherenkov detector, comprising a 614.5 m^2 reflector with a highly pixelized camera in its focal plane, improves the sensitivity of the current array by a factor two and extends its energy domain down to a few tens of GeV. The present part I of the paper gives a detailed description of the fifth H.E.S.S. telescope's camera, presenting the details of both the hardware and the software, emphasizing the main improvements as compared to previous H.E.S.S. camera technology.Comment: 16 pages, 13 figures, accepted for publication in NIM

Open multistate Majorana model

The multistate Majorana model in the presence of dissipation and dephasing is considered. It is proven that increasing the Hilbert space dimension the system becomes more and more fragile to quantum noise. The impossibility to recast the problem in the form of a set of independent spin-$1/2$ problems because of the presence of the noise is pointed out

K2-136: A Binary System in the Hyades Cluster Hosting a Neptune-sized Planet

We report the discovery of a Neptune-size planet (R_p = 3.0 R⊕) in the Hyades Cluster. The host star is in a binary system, comprising a K5V star and M7/8V star with a projected separation of 40 au. The planet orbits the primary star with an orbital period of 17.3 days and a transit duration of 3 hrs. The host star is bright (V = 11.2, J = 9.1) and so may be a good target for precise radial velocity measurements. K2-136A c is the first Neptune-sized planet to be found orbiting in a binary system within an open cluster. The Hyades is the nearest star cluster to the Sun, has an age of 625–750 Myr, and forms one of the fundamental rungs in the distance ladder; understanding the planet population in such a well-studied cluster can help us understand and set constraints on the formation and evolution of planetary systems