Absorption Lines in the Gravitational Lens System MG 0414+0534

Spectra of components A1 +A2 and B of the gravitational lens system MG 0414+0534 taken with the low-resolution imaging spectrograph on the Keck 10 m telescope show that the strong absorption feature seen in a low-resolution spectrum is due to a complex of Fe II lines at redshifts near that of the lensed quasar. The redshift of the lens remains unknown

Digital Smartphone Tracking for COVID-19: Public Health and Civil Liberties in Tension

This Viewpoint compares manual and digital strategies for coronavirus disease 2019 (COVID-19) contact tracing, describes how countries in Asia and Europe have used smartphone tracking, and discusses privacy and discrimination concerns and strategies for balancing public health and civil liberties in the US

Editorial for Special Edition, Digital Representations: Re-Using and Publishing Digital Qualitative Data

This collection of papers comprises five contributions with a social science or social historical perspective that present the current state of the art in the field of re-using and publishing digital qualitative data. The articles address the use of digital sources in qualitative research in both research and teaching, charting types of use over the past 10 years, and looking forward to emerging practices and methods, such as the promise and potential that technological innovations can bring to enable new ways of presenting and publishing qualitative research. Some of the papers make use of direct linking allowing the reader to explore ?live? data sources, offering an opportunity to see how research transparency might be operationalized in the presentation of qualitative findings and reporting. The papers reference major contributions to the literature and present stimulating debates on the topic and build on previously well-cited publications in which the editors have presented state-of- the-art articles on secondary analysis of qualitative data

What Do Nectaris Basin Impact Melt Rocks Look like and Where Can We Find Them?

The formation of the Nectaris basin is a key event defining the stratigraphy of the Moon. Its absolute age, therefore, is a linchpin for lunar bombardment history. Fernandes et al. gave a thorough account of the history of different samples thought to originate in Nectaris, with the upshot being there is little agreement on what samples represent Nectaris, if any. We are revisiting the effort to identify Nectaris basin impact-melt rocks at the Apollo 16 site, to model their emplacement, and to use these parameters to examine other sites where Nectaris impact melt is more abundant and/or more recognizable for potential further study

Optical recording from respiratory pattern generator of foetal mouse brainstem reveals a distributed network

Author Posting. © The Authors, 2005. This is the author's version of the work. It is posted here by permission of Elsevier B. V. for personal use, not for redistribution. The definitive version was published in Neuroscience 137 (2006): 1221-1227, doi:10.1016/j.neuroscience.2005.10.053.Unfailing respiration depends on neural mechanisms already present in mammals before birth. Experiments were made to determine how inspiratory and expiratory neurons are grouped in the brainstem of fetal mice. A further aim was to assess whether rhythmicity arises from a single pacemaker or is generated by multiple sites in the brainstem. To measure neuronal firing, a fluorescent calcium indicator dye was applied to embryonic central nervous systems isolated from mice. While respiratory commands were monitored electrically from third to fifth cervical ventral roots, activity was measured optically over areas containing groups of respiratory neurones, or single neurones, along the medulla from the facial nucleus to the pre-Bötzinger complex. Large optical signals allowed recordings to be made during individual respiratory cycles. Inspiratory and expiratory neurones were intermingled. A novel finding was that bursts of activity arose in a discrete area intermittently, occurring during some breaths, but failing in others. Raised CO2 partial pressure or lowered pH increased the frequency of respiration; neurons then fired reliably with every cycle. Movies of activity revealed patterns of activation of inspiratory and expiratory neurones during successive respiratory cycles; there was no evidence for waves spreading systematically from region to region. Our results suggest that firing of neurons in immature respiratory circuits is a stochastic process, and that the rhythm does not depend on a single pacemaker. Respiratory circuits in fetal mouse brainstem appear to possess a high safety factor for generating rhythmicity, which may or may not persist as development proceeds.Supported by grants from FONDECYT #1010242 and #7010242 to J.E., NIH DC05259 to L.C., the state of FL to K.M., and an Evelyn and Melvin Spiegel Foundation Award for a summer research fellowship at the MBL to J.E

High definition systems in Japan

The successful implementation of a strategy to produce high-definition systems within the Japanese economy will favorably affect the fundamental competitiveness of Japan relative to the rest of the world. The development of an infrastructure necessary to support high-definition products and systems in that country involves major commitments of engineering resources, plants and equipment, educational programs and funding. The results of these efforts appear to affect virtually every aspect of the Japanese industrial complex. The results of assessments of the current progress of Japan toward the development of high-definition products and systems are presented. The assessments are based on the findings of a panel of U.S. experts made up of individuals from U.S. academia and industry, and derived from a study of the Japanese literature combined with visits to the primary relevant industrial laboratories and development agencies in Japan. Specific coverage includes an evaluation of progress in R&D for high-definition television (HDTV) displays that are evolving in Japan; high-definition standards and equipment development; Japanese intentions for the use of HDTV; economic evaluation of Japan's public policy initiatives in support of high-definition systems; management analysis of Japan's strategy of leverage with respect to high-definition products and systems

A Study of Variable Stiffness Alginate Printing for Medical Applications

Technologies for multi-material 3D-printing of anatomical shapes are useful both for fabrication of heterogeneous cell-seeded implants as well as for fabrication of synthetic models for surgical planning and training. For both these applications, it would be desirable to print directly with biological materials to best emulate the target’s properties. Using a novel material platform, we describe a series of experiments attempting to print variable-stiffness hydrogels. We vary compliances by alternating 2% alginate hydrogel and a Dextran-infused calcium chloride post-crosslinker. Stiffness throughout the construct ranged from 4 kPa to 20 kPa as a function of post-crosslinker concentration, which was spatially specified by the user.Mechanical Engineerin

Improved Quality of 3D-Printed Tissue Constructs Through Enhanced Mixing of Alginate Hydrogels

While alginate hydrogel is a desirable material platform for Solid Freeform Fabrication (SFF) of cell-seeded tissue engineering scaffolds, achieving consistently high-quality results can be challenging. Local variations in the material properties cause inconsistent material deposition behavior and consequently decrease the resultant geometric fidelity of the construct. The effects of gel mixing on material property consistency, geometric fidelity, and cell viability were characterized in an attempt to improve the formulation’s compatibility with SFF processing. Material homogeneity was quantified through a novel experimental setup composed of an EnduraTEC mechanical test-frame and custom syringe-extrusion jig. Cell viability and geometric fidelity were assessed using standard protocol. The baseline mechanical stiffness of the printed samples was 16±3 kPa (n=6). We found that increasing mixing reduced material inconsistency and improved geometric fidelity, without adversely affecting cell viability: the printed construct quality was drastically improved by increasing mixing well beyond previously established limits.Mechanical Engineerin