Vaporization and decomposition kinetics of candidate re-entry blackout suppressants in low-pressure flames

Measurement of thermal accommodation coefficients between liquids and high temperature gases in low pressure reentry communications blackout interval

The Setting Up of an Introductory Woodworking Course and Basic Shop

Not provided

Polarized-interferometer feasibility study

The feasibility of using a polarized-interferometer system as a rendezvous and docking sensor for two cooperating spacecraft was studied. The polarized interferometer is a radio frequency system for long range, real time determination of relative position and attitude. Range is determined by round trip signal timing. Direction is determined by radio interferometry. Relative roll is determined from signal polarization. Each spacecraft is equipped with a transponder and an antenna array. The antenna arrays consist of four crossed dipoles that can transmit or receive either circularly or linearly polarized signals. The active spacecraft is equipped with a sophisticated transponder and makes all measurements. The transponder on the passive spacecraft is a relatively simple repeater. An initialization algorithm is developed to estimate position and attitude without any a priori information. A tracking algorithm based upon minimum variance linear estimators is also developed. Techniques to simplify the transponder on the passive spacecraft are investigated and a suitable configuration is determined. A multiple carrier CW signal format is selected. The dependence of range accuracy and ambiguity resolution error probability are derived and used to design a candidate system. The validity of the design and the feasibility of the polarized interferometer concept are verified by simulation

The first direct detection of gravitational waves opens a vast new frontier in astronomy

The first direct detection of gravitational waves (GWs), announced on 11 February 2016, has opened a vast new frontier in astronomy. Albert Einstein predicted the existence of these waves about a century ago as a consequence of his general theory of relativity. Radio astronomy observations of the binary pulsar system PSR 1913 + 16 over a 20 year period beginning in 1975 provided strong observational evidence that gravitational waves carried energy away from the orbits of neutron stars at precisely the level predicted by general relativity (GR). This relentless conversion of orbital energy into gravitational wave energy causes binary orbits to decay until the objects eventually collide and merge. The frontier of precision measurement science, using laser interferometers, was pushed for more than four decades to achieve this first direct detection, marking a milestone in experimental physics and engineering. Even more significantly, this milestone also opens a new window onto our universe and a completely new kind of astronomy to explore

The past, present and future of research on judgment and decision making in sport

Objectives: The study of judgment and decision-making in sports is at least as old as the anniversary of FEPSAC we celebrate with this special issue. It seems therefore appropriate to look into the past, present and future of this topic. Design: For the past, a focus of the review is relating the European perspective of the co-authors into a larger frame of areas in judgment and decision making within the last 50 years and beyond. Method/Results/Conclusions: For the present, scientific current developments will be structured as judgments from the most influential perspectives such as the economical, social cognition, ecological dynamics or cognitive approaches illustrating some milestones in research on judgment and decision-making in sports of today. For the future, potentials of the field will be structured based on theory, methodology and practical applications showcasing challenges for the next decades of research ahead of us

No impact of instructions and feedback on task integration in motor learning

This study examined the effect of instructions and feedback on the integration of two tasks. Task-integration of covarying tasks are thought to help dual-task performance. With complete task integration of covarying dual tasks, a dual-task becomes more like a single task and dual-task costs should be reduced as it is no longer conceptualized as a dual task. We covaried a tracking task with an auditory go/no-go task and tried to manipulate the extent of task-integration by using two different sets of instructions and feedback. A group receiving task-integration promoting instructions and feedback (N = 18) and a group receiving task-separation instructions and feedback (N = 20) trained a continuous tracking task. The tracking task covaried with the auditory go/no-go reaction time task because high-pitch sounds always occurred 250 ms before turns, which has been demonstrated to foster task integration before. The tracking task further contained a repeating segment to investigate implicit learning. Results showed that neither instructions, feedback, nor participants’ conceptualization of performing a single task vs. a dual task significantly affected task-integration. However, the covariation manipulation improved performance in both the tracking and the go/no-go task, exceeding performance in non-covarying and single tasks. We conclude that task-integration between covarying motor tasks is a robust phenomenon that is not influenced by instructions or feedback

How to not induce SNAs: The insufficiency of directional force.

People respond faster to smaller numbers in their left space and to larger numbers in their right space. Here we argue that movements in space contribute to the formation of spatial-numerical associations (SNAs). We studied the impact of continuous isometric forces along the horizontal or vertical cardinal axes on SNAs while participants performed random number production and arithmetic verification tasks. Our results suggest that such isometric directional force do not suffice to induce SNAs. [Abstract copyright: Copyright: © 2023 Michirev et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Motional sidebands and direct measurement of the cooling rate in the resonance fluorescence of a single trapped ion

Resonance fluorescence of a single trapped ion is spectrally analyzed using a heterodyne technique. Motional sidebands due to the oscillation of the ion in the harmonic trap potential are observed in the fluorescence spectrum. From the width of the sidebands the cooling rate is obtained and found to be in agreement with the theoretical prediction.Comment: 4 pages, 4 figures. Final version after minor changes, 1 figure replaced; to be published in PRL, July 10, 200

Signature Amino Acid Changes in Latent Membrane Protein 1 Distinguish Epstein–Barr Virus Strains

Sequence variations in the Epstein-Barr virus (EBV) latent membrane protein 1 gene have been described in numerous EBV-associated tumors with some of these variations, most notably a 30-base pair deletion in the cytoplasmic carboxyl-terminal domain, suggested as associated with an increase in tumorigenicity. In this study, EBV DNA sequence was determined from 92 tissue specimens or cell lines, including nasopharyngeal carcinoma, oral hairy leukoplakia, post-transplant lymphoma, post-transplant without pathology, mononucleosis, Burkitt's lymphoma, parotid tumor, and normal from distinct geographical regions. The amino- and carboxyl-terminal sequences and, in some cases, the full-length sequences of latent membrane protein 1 were determined. Characteristic sequence patterns distinguished strains, with the carboxyl-terminal sequence being the most informative in distinguishing among the strains. Phylogenetic relationships between strains were determined, as were signature amino acid changes that discriminate between them. A correlation between strain and disease or strain and geographic location was not detected. The sequence variation and signature sequences identified at least seven distinct strains, as well as hybrid strains that apparently result from recombination

Communications Biophysics

Contains reports on two research projects