“Heinrich events” (& sediments): A history of terminology and recommendations for future usage

IF/01500/2014info:eu-repo/semantics/publishedVersio

Beam Dynamics Studies for SRF Photoinjectors

The SRF photoinjector combines the advantages of photo assisted production of high brightness, short electron pulses and high gradient, low loss continuous wave CW operation of a superconducting radiofrequency SRF cavity. The paper discusses beam dynamics considerations for ERL class applications of SRF photoinjectors. One case of particular interest is the design of the SRF photoinjector for BERLinPro, an ERL test facility demanding a high brightness beam with an emittance better than 1 mm mrad at 77 pC and average current of 100 m

Wigner Glass, Spin-liquids, and the Metal-Insulator Transition

Recent experiments on the two dimensional electron gas in various semiconductor devices have revealed an unexpected metal-insulator transition and have challenged the previously held assumption that there is no such transition in two dimensions. While the experiments are still at the stage of rapid development, it is becoming evident that they cannot be understood from the conventional perspective of weak interactions. In the present paper, we propose the following. (1) The low-density insulating state is the Wigner Glass, a phase with quasi-long-range translational order and competing ferromagnetic and antiferromagnetic spin-exchange interactions. (2) The transition is the melting of this Wigner Glass, disorder being the agent allowing the transition to be second order. (3) Within the Wigner Glass phase, there are at least two, distinct magnetic ground-states, a ferromagnetic state at very low electron density and a spin-liquid state with a spin pseudo-gap at higher densities. (4) The metallic side of the transition is a non-Fermi liquid. These conclusions are encapsulated in Figure 1 which presents the proposed phase diagram as a function of disorder strength and density; we also suggest experimental signatures of the various phases and transitions.Comment: Revised manuscript 6 pages, 1 figure redrawn for clarity; discussion of experiments expande

From protease to decarboxylase: the molecular metamorphosis of phosphatidylserine decarboxylase

Background: Phosphatidylserine decarboxylase (PSD) undergoes an autoendoproteolytic cleavage but the mechanism has not been defined. Results: PSD proenzyme processing occurs by a canonical serine protease mechanism catalyzed by a conserved aspartate-histidine-serine triad. Conclusion: PSD proenzyme executes a proteolytic reaction in cis that creates the active site of the decarboxylase. Significance: The mechanism of autoendoproteolyic processing of PSDs across phyla has been elucidated

Millennial-scale deep ocean ventilation and sea-surface variability during the last four glacial cycles : a new assessment for the Northern Hemisphere ice-sheet growth

AGU Fall Meeting, S. Francisco (USA), 19-14 December 2007, Suppl., Abstract PP44B-0

DebriSat - A Planned Laboratory-Based Satellite Impact Experiment for Breakup Fragment Characterization

DebriSat is a planned laboratory ]based satellite hypervelocity impact experiment. The goal of the project is to characterize the orbital debris that would be generated by a hypervelocity collision involving a modern satellite in low Earth orbit (LEO). The DebriSat project will update and expand upon the information obtained in the 1992 Satellite Orbital Debris Characterization Impact Test (SOCIT), which characterized the breakup of a 1960 's US Navy Transit satellite. There are three phases to this project: the design and fabrication of an engineering model representing a modern, 50-cm/50-kg class LEO satellite known as DebriSat; conduction of a laboratory-based hypervelocity impact to catastrophically break up the satellite; and characterization of the properties of breakup fragments down to 2 mm in size. The data obtained, including fragment size, area ]to ]mass ratio, density, shape, material composition, optical properties, and radar cross ]section distributions, will be used to supplement the DoD fs and NASA fs satellite breakup models to better describe the breakup outcome of a modern satellite. Updated breakup models will improve mission planning, environmental models, and event response. The DebriSat project is sponsored by the Air Force fs Space and Missile Systems Center and the NASA Orbital Debris Program Office. The design and fabrication of DebriSat is led by University of Florida with subject matter experts f support from The Aerospace Corporation. The major milestones of the project include the complete fabrication of DebriSat by September 2013, the hypervelocity impact of DebriSat at the Air Force fs Arnold Engineering Development Complex in early 2014, and fragment characterization and data analyses in late 2014

Dental Hygiene and Dental Assistant Students\u27 Simulated DVI Radiographic Match Accuracy: A Pilot Study

Purpose Allied dental health care professionals have served on disaster victim identification (DVI) teams; however, the literature is void of statistical measures regarding transferable skills and disaster preparedness. The purpose of this study was to assess second year dental hygiene and dental assistant students’ match accuracy for simulated DVI radiographs and compare the match accuracy between the student groups. Methods Five patient cases were chosen at random to retrospectively collect sets of digital bitewing radiographs from two time periods. The five retrospectively selected sets of images served as simulated antemortem (AM) and postmortem (PM) radiographs. A convenience sample of second year dental hygiene and dental assistant students from two institutions (n=48) were invited to participate in this IRB-exempt descriptive observational study. The previously selected AM and PM images were randomly mismatched, and participants were asked to visually compare the image sets and indicate the matches using a drag and drop feature in an electronic survey instrument. Descriptive statistics were used to analyze the data; the significance level was set at α=0.05. Results A total of 41 dental hygiene and dental assistant students agreed to participate for a response rate of 85.4%. Eighty-five percent of the participants accurately matched five out of five sets while the remaining 15% accurately matched three out of five sets. A one-sample binomial proportion test revealed that 80% of the participants were able to match at least four out of five sets (p\u3c0.001). Dental hygiene students demonstrated increased matching performance as compared to dental assisting students (p=0.013). Conclusion Both dental hygiene and dental assistant students demonstrated transferable DVI skills to accurately match simulated AM and PM radiographs. Future research is needed in a larger sample to develop and assess best practices of DVI training to build on existing skills for allied dental health care professionals