702 research outputs found
STS-1 operational flight profile. Volume 5: Descent, cycle 3
The trajectory data presented are to be used for orbiter systems and subsystems evalation, flight and mission control center software verification, flight techniques and timeline development, crew training, and evaluation of operational mission suitability. The entry profile is very similar to cycle 2, however, elevon and body flap temperature margins have increased and the elevon schedule was changed. The terminal area energy management (TAEM) profile was completely reshaped to conform with new angle of attack constraints and left hand turn around the heading alignment cylinder. Also, the entry/TAEM interface was adjusted to minimize guidance induced angle of attack transients across the interface. The approach and landing phase was reshaped for a 20 deg glideslope and reduced velocity at touchdown. The definition of the runway threshold was standardized for all landing sites. This results in a shift at Edwards Air Force Base in aim points and touchdown relative to the threshold of 1000 feet. The rollout remains essentially unchanged with the exception of the speedbrake, which is now deployed to 50 percent at touchdown
Principles of membrane protein interactions with annular lipids deduced from aquaporin-0 2D crystals
We have previously described the interactions of aquaporin-0 (AQP0) with dimyristoyl phosphatidylcholine (DMPC) lipids. We have now determined the 2.5 Å structure of AQP0 in two-dimensional (2D) crystals formed with Escherichia coli polar lipids (EPLs), which differ from DMPC both in headgroups and acyl chains. Comparison of the two structures shows that AQP0 does not adapt to the different length of the acyl chains in EPLs and that the distance between the phosphodiester groups in the two leaflets of the DMPC and EPL bilayers is almost identical. The EPL headgroups interact differently with AQP0 than do those of DMPC, but the acyl chains in the EPL and DMPC bilayers occupy similar positions. The interactions of annular lipids with membrane proteins seem to be driven by the propensity of the acyl chains to fill gaps in the protein surface. Interactions of the lipid headgroups may be responsible for the specific interactions found in tightly bound lipids but seem to have a negligible effect on interactions of generic annular lipids with membrane proteins
Electric-field noise from carbon-adatom diffusion on a Au(110) surface: first-principles calculations and experiments
The decoherence of trapped-ion quantum gates due to heating of their motional
modes is a fundamental science and engineering problem. This heating is
attributed to electric-field noise arising from the trap-electrode surfaces. In
this work, we investigate the source of this noise by focusing on the diffusion
of carbon-containing adsorbates on the surface of Au(110). We show by density
functional theory, based on detailed scanning probe microscopy, how the carbon
adatom diffusion on the gold surface changes the energy landscape, and how the
adatom dipole moment varies with the diffusive motion. A simple model for the
diffusion noise, which varies quadratically with the variation of the dipole
moment, qualitatively reproduces the measured noise spectrum, and the estimate
of the noise spectral density is in accord with measured values.Comment: 8 pages, 6 figure
Investigation on the Use of a FLIR (Forward Looking Infrared) Camera to Detect Relationships Between Internal and Surface Temperatures of Beef Carcasses During Chilling
The objective of this study was to collect preliminary data on the efficacy of using thermal imaging technology as a means to assess beef carcass chilling
Influence of Post-harvest Circulatory Rinse on Tenderness and Objective Color of Cow Striploin Steaks
The objective of this study was to compare the effect of a post-harvest rinse of an isotonic solution through the circulatory system on tenderness of steaks from cows
Observation of quantum oscillations between a Josephson phase qubit and a microscopic resonator using fast readout
We have detected coherent quantum oscillations between Josephson phase qubits
and microscopic critical-current fluctuators by implementing a new state
readout technique that is an order of magnitude faster than previous methods.
The period of the oscillations is consistent with the spectroscopic splittings
observed in the qubit's resonant frequency. The results point to a possible
mechanism for decoherence and reduced measurement fidelity in superconducting
qubits and demonstrate the means to measure two-qubit interactions in the time
domain
Medically attended pediatric influenza during the resurgence of the Victoria lineage of influenza B virus
SummaryObjectivesDuring the 2002–2003 season, a new variant of influenza B co-circulated with influenza A viruses. This study examines the characteristics and outcomes of children with influenza A and B virus infection vs. other acute respiratory illnesses.MethodsA retrospective chart review was performed on children with laboratory-confirmed influenza infection, and influenza negative acute respiratory illnesses that prompted a hospital visit.ResultsChildren with influenza were more often previously healthy and presenting with upper respiratory symptoms, while influenza negative patients typically had underlying medical conditions, and lower respiratory tract disease. Children with influenza B were older, were more likely to be in school, and presented with myositis more frequently than those with influenza A. A third of children with influenza A, and 42% with influenza B required hospitalization. The highest hospitalization rates were in infants under one year. No healthy children, and only 15% of those with chronic medical problems, had received influenza vaccine. Vaccine efficacy was estimated to be 82.6%.ConclusionsMost children with influenza were previously healthy. Overall, a third of children with influenza required hospitalization. Influenza A and B were clinically indistinguishable, except for older age and higher incidence of myositis in patients with influenza B. Influenza vaccine coverage in both healthy and high-risk children was low
What do people do with porn? qualitative research into the consumption, use and experience of pornography and other sexually explicit media
This article reviews qualitative research into the consumption of pornography and other sexually explicit media emerging from a range of subject areas. Taking a critique of quantitative methods and a focus on measuring sexual effects and attitudes as a starting point, it considers the proposition that qualitative work is more suited to an examination of the complex social, cultural and political constructions of sexuality. Examining studies into the way men, women and young people see, experience, and use explicit media texts, the article identifies the key findings that have emerged. Qualitative work shows that sexuality explicit media texts are experienced and understood in a variety of ways and evoke strong and often contradictory reactions, not all of which are represented in public debates about pornography. These texts function in a range of different ways, depending on context; as a source of knowledge, a resource for intimate practices, a site for identity construction, and an occasion for performing gender and sexuality. The article reviews these studies and their findings, identifying what they suggest about directions for future research, both in terms of developing methodology and refining approaches to sexuality and media consumption.</p
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