1,237 research outputs found
First sensitivity limits of the ALPS TES detector
The Any Light Particle Search II (ALPS II) requires a sensitive detection of
1064 nm photons. Thus, a low dark count rate (DC) and a high detection
efficiency (DE) is needed. ALPS has set up a transition-edge sensor (TES)
detector system, namely the ALPS TES detector. It is found that thermal photons
from room temperature surfaces are the main contribution of dark counts for
1064 nm photon signals. Furthermore, the current setup of the ALPS TES detector
shows an improvement compared to using the ALPS I detector.Comment: 4 pages, 1 figure; proceedings of 10th Patras Workshop on Axions,
WIMPs, and WISPs, Geneva, CERN, 29 June to 4 July 201
A preferred vision for administering high schools : a reflective essay
Without an educated population, this nation would not be as strong as it is, nor will it be as strong as it could be. We still have a strong educational focus in the state of Iowa which lends us to believe that we can stand alone. That might not be the case in the future. Our state, communities, school districts, parents, teachers and students must keep striving to be the best and not rest on its laurels. We can not afford to let a generation of our youth slip, while we entertain a policy of isolation. I believe that the state of Iowa will take the step into the next millennium and lead the nation with the development of a strong set of standards and benchmarks that give all students a chance to learn
A Discussion of Audiovisual Archival Methods: Conversations with Institutions, Content Creators, Archival System Designers and Integrators
[Excerpt:] My survey of local, national, and international audiovisual archival methods highlighted the underlying cause of why archiving media for video has yet to be refined to an easily-compartmentalized process. Companies who acknowledge that archiving their media properly is a concern still see it as unglamorous and perhaps even unworthy of committing a significant-enough portion of their budgets toward a sufficient solution. Finding âa solutionâ begins to look like the lifeâs work of an artist rather than a âPoint A to Point Bâ procedure. In my discussions with various representatives of content creators, archival system integrators, and institutional archivists, I hoped to discover success stories. In the end, I was shown just how complex the archiving process is, and how this inscrutability makes it virtually impossible to answer the question, âHow much does a proper archive cost?
Methods and Informatics for Gas-Phase Structural Biology and Drug Discovery
Methods for rapid interrogation of structure and stability attributes of proteins and protein complexes are becoming increasingly important for developing our understanding of biology and the development of pharmaceuticals. Gas-phase technologies such as mass spectrometry and ion mobility spectrometry have proven valuable in these endeavors, as they provide unique perspectives on the solution-phase equilibrium of protein complexes and their conformations. Before fully harnessing the information derived from these gas-phase techniques, new approaches for data analysis and mechanistic understanding of gas-phase protein structure are necessary. In this dissertation, we develop ion mobility mass spectrometry methods and informatics for the study of gas-phase proteins, multiprotein complexes, and protein-small molecule complexes.
In the first half of the dissertation, novel data analysis tools and experimental methodologies are outlined for the study of gas-phase protein unfolding. After providing the software tools necessary for robust analysis of gas-phase unfolding trajectories in Chapter 2, we turned our attention to understanding the mechanism of unfolding for large multidomain proteins. In Chapter 3, we focus on the factors driving changes in unfolding trajectories for a variety of serum albumin homologues, and through the use of novel unfolding experiments utilizing chemical probes and non-covalent protein constructs, a detailed mechanism for solvent-free protein unfolding is provided.
Subsequent chapters in the dissertation focus on the characterization of multiprotein complexes, especially through the use of ion mobility-mass spectrometry and coarse-grained modeling. In chapter 4, we develop and benchmark new algorithms for translating ion mobility and mass spectrometry datasets into coarse grained models. These studies outline the limits in current coarse-graining methodologies, and define the minimum restraint sets necessary to generate high confidence multiprotein models. Additionally, best practices for dealing with ambiguous models resulting from sparse datasets are described. In chapter 5, the tools developed in the previous chapter are applied to structurally characterize the urease pre-activation complex, a transient 18-subunit complex that is a target for inhibition of urease-related pathology. When our ion mobility-mass spectrometry datasets are combined with previously published chemical crosslinking and x-ray scattering data, a discrete population of conformations for the urease pre-activation complex emerges which compares favorably to previous models generated using computational techniques.
In Chapter 6, I highlight more applications of ion mobility-mass spectrometry to engineered and naturally occurring protein complexes. These applications highlight the power of ion mobility mass-mass spectrometry datasets for rapid analysis of protein oligomerization state and structure, providing a basis for further integration of the technology into pharmaceutical and structural biology workflows.PHDChemistryUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/138785/1/joeesch_1.pd
Characterization, 1064 nm photon signals and background events of a tungsten TES detector for the ALPS experiment
The high efficiency, low-background, and single-photon detection with
transition-edge sensors (TES) is making this type of detector attractive in
widely different types of application. In this paper, we present first
characterizations of a TES to be used in the Any Light Particle Search (ALPS)
experiment searching for new fundamental ultra-light particles. Firstly, we
describe the setup and the main components of the ALPS TES detector (TES,
millikelvin-cryostat and SQUID read-out) and their performances. Secondly, we
explain a dedicated analysis method for single-photon spectroscopy and
rejection of non-photon background. Finally, we report on results from
extensive background measurements. Considering an event-selection, optimized
for a wavelength of , we achieved a background suppression of
with a efficiency for photons passing the
selection. The resulting overall efficiency was with a dark count rate
of . We observed that pile-up events of thermal
photons are the main background component.Comment: 17 pages, 9 figures. Accepted by Journal of Modern Optic
Rules, Discretion, and Central Bank Independence: The German Experience 1880 - 1989
Theories of rules and discretion have become a corner stone in the formulation of macroeconomic policy. They suggest that monetary policy rules are first best in terms of social welfare. However, if commitment is not feasible, delegating monetary policy to an independent and conservative central bank can be second best. Monetary policy in Germany during the past one hundred years provides an excellent case to assess the empirical evidence on the use of rules and central bank independence in monetary policy making. Since the creation of a central monetary authority in 1876, Germany has participated in four monetary regimes: the pre-war gold standard, the inter-war gold standard, the Bretton Woods system, and the floating exchange rate regime. With the exception of the two world war periods German monetary policy was geared primarily towards maintaining price stability and characterized by a high degree of formal and practical central bank independenc
A registered report of a crossover study on the effects of face masks on walking adaptability in people with Parkinson's disease and multiple sclerosis
Background Face masks protrude into the lower visual field causing reduced perception of visual stimuli, potentially making obstacle avoidance during walking more difficult and increasing fall risk. Recommendations on walking and mask wearing for older adults have been debated, with no clear consensus on the various factors interacting and influencing walking safety while wearing a face mask. It is particularly important to address this issue in populations at an increased risk of falls. Therefore, this study aims to investigate the effects of mask-wearing on objectively measured walking adaptability in people with Parkinson's disease and Multiple Sclerosis. Methods 50 patients with either Parkinson's disease or Multiple Sclerosis attending inpatient neurorehabilitation will be recruited to participate in this crossover study. Performance during a standardized gait adaptability (C-Gait) test on a VR-based treadmill (C-Mill+VR), as well as during clinical mobility tests (10-meter walk test, Timed Up & Go test, and stair ambulation) will be measured with and without an FFP2- mask (order randomized). In addition, participants will be asked about their perceived performance and perceived safety during the tests with and without a mask. Performance on the seven C-Gait subtests is based on centre of pressure-derived measures of foot placement in relation to the different tasks. These are averaged and added to a cognitive C-Gait task to give the overall composite score (primary outcome). Secondary outcomes will include the different subscores and clinical mobility tests. Potential significance This study will make an important contribution to an ongoing debate regarding recommendations persons with and without a neurological disease should be given regarding wearing a face mask while walking. Furthermore, the study will complement the existing scientific discourse with clinical data from people with a neurological disease for whom falls, mobility deficits and mask wearing may be more frequent, which can help inform evidence-based recommendations.ISSN:1932-620
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