On the distortions in calculated GW parameters during slanted atmospheric soundings

The significant distortions introduced in the measured atmospheric gravity wavelengths by soundings other than those in vertical and horizontal directions, are discussed as a function of the elevation angle of the sounding path and the gravity wave aspect ratio. Under- or overestimation of real vertical wavelengths during the measurement process depends on the value of these two parameters. The consequences of these distortions on the calculation of the energy and the vertical flux of horizontal momentum are analyzed and discussed in the context of two experimental limb satellite setups: GPS-LEO radio occultations and TIMED/SABER ((Atmosphere using Broadband Emission Radiometry/Thermosphere-Ionosphere-Mesosphere-Energetics and Dynamics)) measurements. Possible discrepancies previously found between the momentum flux calculated from satellite temperature profiles, on site and from model simulations, may to a certain degree be attributed to these distortions. A recalculation of previous momentum flux climatologies based on these considerations seems to be a difficult goal.Fil: de la Torre, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Austral. Facultad de Ingeniería; ArgentinaFil: Alexander, Pedro Manfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Schmidt, Torsten. German Research Centre for Geosciences; AlemaniaFil: Llamedo Soria, Pablo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Austral. Facultad de Ingeniería; ArgentinaFil: Hierro, Rodrigo Federico. Universidad Austral. Facultad de Ingeniería; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

riverSedge 1981 v.4 no.1

Richard Peabody -- Katharyn Machan Aal -- Joan Rohr Myers -- Ronald James Costarella -- William M. White -- Jan Seale -- Edward C. Lynskey -- David Ruenzel -- Paul A. Lamphear -- Roger Jones -- Patricia Grant -- Lyn Lifshin -- Ted Daniel 27, -- Thomas Bost -- David E. Cowen -- Robert B. Bowie -- Richard Gaillard -- Peter Krok -- Robert F. Whisler -- Joyce Meier -- Gloria Hulk -- Jeanne Ranker -- Katharine Privett -- Robert F. Trotter -- John J. Soldo -- John N. Miller.https://scholarworks.utrgv.edu/riversedge/1010/thumbnail.jp

riverSedge Fall 1979 v.3 no.2

R. E. Sodowsky -- Jan Villarrubia -- Roger Jones -- J. W. Rivers -- Dawna Maydak Andrejcak -- Barbara Jameson -- T. C. Buell -- Timm Louis -- Susan Baran -- Sarah Brown Weitzman -- Allan Morris -- Robert Necker -- David E. Cowen -- Randall Schluter -- Jeremy Palmer -- Phillip Corwin -- V. T. Abercrombie -- A. C. Kimball -- Tonita S. Gardner -- Contributors.https://scholarworks.utrgv.edu/riversedge/1008/thumbnail.jp

Thermodynamics of Quantum Feedback Cooling

This is the final version. Available on open access from MDPI via the DOI in this reocrdThe ability to initialize quantum registers in pure states lies at the core of many applications of quantum technologies, from sensing to quantum information processing and computation. In this paper, we tackle the problem of increasing the polarization bias of an ensemble of two-level register spins by means of joint coherent manipulations, involving a second ensemble of ancillary spins and energy dissipation into an external heat bath. We formulate this spin refrigeration protocol, akin to algorithmic cooling, in the general language of quantum feedback control, and identify the relevant thermodynamic variables involved. Our analysis is two-fold: on the one hand, we assess the optimality of the protocol by means of suitable figures of merit, accounting for both its work cost and effectiveness; on the other hand, we characterise the nature of correlations built up between the register and the ancilla. In particular, we observe that neither the amount of classical correlations nor the quantum entanglement seem to be key ingredients fuelling our spin refrigeration protocol. We report instead that a more general indicator of quantumness beyond entanglement, the so-called quantum discord, is closely related to the cooling performance.COST ActionUniversity of NottinghamSpanish MINECOGeneralitat de Catalunya Consejo Interdepartamental de Investigación e Innovación TecnológicaAcademy of FinlandFoundational Questions InstituteEuropean Research Counci

A Method to Determine Gravity Wave Net Momentum Flux, Propagation Direction, and “Real” Wavelengths: A GPS Radio Occultations Soundings Case Study

Atmospheric gravity waves (GW) serve as an essential mechanism in the transport of energy and momentum flux from the low to the upper atmosphere. In the last decades satellite observations have become an important part in the analysis of GW due to their global and frequent coverage. Present procedures often provide GW absolute momentum flux (MF), ambiguous 3‐D propagation direction, and apparent vertical wavelengths. We here introduce a method with close sounding quartets, which allows the calculation for GW of the net MF, the definite propagation direction, and “real” wavelengths. Among the satellite observational techniques, Global Positioning System (GPS) radio occultation (RO) retrievals provide temperature profiles that after adequate processing may yield GW properties like wavelengths, MF, and energy. Our procedure is illustrated by an example under requirements that tend to ensure that four GPS RO soundings are observing the same GW. The future increase of satellite measuring devices due to new missions (including GPS RO) will lead to a higher spatial and temporal density of profiles that may eventually allow the attainment of GW climatologies of net MF, propagation direction, and “real” vertical wavelengths.Fil: Alexander, Pedro Manfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Schmidt, T.. German Research Centre for Geosciences; AlemaniaFil: de la Torre, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Austral. Facultad de Ingeniería; Argentin

Data extraction methods for systematic review (semi)automation: A living systematic review [version 1; peer review: awaiting peer review]

Background: The reliable and usable (semi)automation of data extraction can support the field of systematic review by reducing the workload required to gather information about the conduct and results of the included studies. This living systematic review examines published approaches for data extraction from reports of clinical studies. Methods: We systematically and continually search MEDLINE, Institute of Electrical and Electronics Engineers (IEEE), arXiv, and the dblp computer science bibliography databases. Full text screening and data extraction are conducted within an open-source living systematic review application created for the purpose of this review. This iteration of the living review includes publications up to a cut-off date of 22 April 2020. Results: In total, 53 publications are included in this version of our review. Of these, 41 (77%) of the publications addressed extraction of data from abstracts, while 14 (26%) used full texts. A total of 48 (90%) publications developed and evaluated classifiers that used randomised controlled trials as the main target texts. Over 30 entities were extracted, with PICOs (population, intervention, comparator, outcome) being the most frequently extracted. A description of their datasets was provided by 49 publications (94%), but only seven (13%) made the data publicly available. Code was made available by 10 (19%) publications, and five (9%) implemented publicly available tools. Conclusions: This living systematic review presents an overview of (semi)automated data-extraction literature of interest to different types of systematic review. We identified a broad evidence base of publications describing data extraction for interventional reviews and a small number of publications extracting epidemiological or diagnostic accuracy data. The lack of publicly available gold-standard data for evaluation, and lack of application thereof, makes it difficult to draw conclusions on which is the best-performing system for each data extraction target. With this living review we aim to review the literature continually

Parallax and Distance Estimates for Twelve Cataclysmic Variable Stars

We report parallax and distance estimates for twelve more cataclysmic binaries and related objects observed with the 2.4m Hiltner telescope at MDM Observatory. The final parallax accuracy is typically about 1 mas. For only one of the twelve objects, IR Gem, do we fail to detect a significant parallax. Notable results include distances for V396 Hya (CE 315), a helium double degenerate with a relatively long orbital period, and for MQ Dra (SDSSJ155331+551615), a magnetic system with a very low accretion rate. We find that the Z Cam star KT Persei is physically paired with a K main-sequence star lying 15 arcsec away. Several of the targets have distance estimates in the literature that are based on the white dwarf's effective temperature and flux; our measurements broadly corroborate these estimates, but tend to put the stars a bit closer, indicating that the white dwarfs may have rather larger masses than assumed. As a side note, we briefly describe radial velocity spectroscopy that refines the orbital period of V396 Hya to 65.07 +- 0.08 min.Comment: Accepted for Astronomical Journal. 19 pages, no figure

Towards segmentation and spatial alignment of the human embryonic brain using deep learning for atlas-based registration

We propose an unsupervised deep learning method for atlas based registration to achieve segmentation and spatial alignment of the embryonic brain in a single framework. Our approach consists of two sequential networks with a specifically designed loss function to address the challenges in 3D first trimester ultrasound. The first part learns the affine transformation and the second part learns the voxelwise nonrigid deformation between the target image and the atlas. We trained this network end-to-end and validated it against a ground truth on synthetic datasets designed to resemble the challenges present in 3D first trimester ultrasound. The method was tested on a dataset of human embryonic ultrasound volumes acquired at 9 weeks gestational age, which showed alignment of the brain in some cases and gave insight in open challenges for the proposed method. We conclude that our method is a promising approach towards fully automated spatial alignment and segmentation of embryonic brains in 3D ultrasound

Inter-individual stereotypy of the Platynereis larval visual connectome

This is the final version of the article. Available from the publisher via the DOI in this record.Developmental programs have the fidelity to form neural circuits with the same structure and function among individuals of the same species. It is less well understood, however, to what extent entire neural circuits of different individuals are similar. Previously, we reported the neuronal connectome of the visual eye circuit from the head of a Platynereis dumerilii larva (Randel et al., 2014). We now report a full-body serial section transmission electron microscopy (ssTEM) dataset of another larva of the same age, for which we describe the connectome of the visual eyes and the larval eyespots. Anatomical comparisons and quantitative analyses of the two circuits reveal a high inter-individual stereotypy of the cell complement, neuronal projections, and synaptic connectivity, including the left-right asymmetry in the connectivity of some neurons. Our work shows the extent to which the eye circuitry in Platynereis larvae is hard-wired.The research leading to these results received funding from the European Research Council under the European Union’s Seventh Framework Programme (FP7/2007–2013)/European Research Council Grant Agreement 260821.European Research Council (ERC): Grant Agreement 260821, Gaspar Jekel