30,206 research outputs found
Plant respirometer enables high resolution of oxygen consumption rates
Plant respirometer permits high resolution of relatively small changes in the rate of oxygen consumed by plant organisms undergoing oxidative metabolism in a nonphotosynthetic state. The two stage supply and monitoring system operates by a differential pressure transducer and provides a calibrated output by digital or analog signals
Dispositional Hardiness and Women’s Well-Being Relating to Gender Discrimination: The Role of Minimization
Three studies examined whether personality-based hardiness would be associated with mental health benefits in contexts of gender discrimination. Hardy women encountering both a laboratory simulation and a hypothetical scenario of discrimination showed greater self-esteem and less negative affect than low hardy women. However, these benefits were mediated by the use of specific attributions, suggesting that the well-being in hardy women may have been achieved through minimizing the pervasiveness of discrimination. Study three showed this mediation pattern occurred only for participants exposed to higher threat scenarios versus lower threat scenarios of discrimination. Thus, minimizing the pervasiveness of discrimination may have been a threat-reducing tool for high hardy women. Bandura’s (1997) self-efficacy theory was used as a possible explanation for this finding
Raising the visibility of protected data: A pilot data catalog project
Sharing research data that is protected for legal, regulatory, or contractual reasons can be challenging and current mechanisms for doing so may act as barriers to researchers and discourage data sharing. Additionally, the infrastructure commonly used for open data repositories does not easily support responsible sharing of protected data. This chapter presents a case study of an academic university library’s work to configure the existing institutional data repository to function as a data catalog. By engaging in this project, university librarians strive to enhance visibility and access to protected datasets produced at the institution and cultivate a data sharing culture
The Role of Hardiness in Moderating the Relationship between Global/Specific Attributions and Actions against Discrimination
In this study, we proposed that individual differences in hardiness may moderate the relationship between global attributions and actions against discrimination. Specifically, global attributions were expected to predict decreased endorsement of actions to combat discrimination among low hardy women. In contrast, global attributions were expected to predict increased endorsement of actions among high hardy women. High and low hardy women were exposed to a laboratory situation of discrimination, and their attributions for, and responses to, discrimination were then assessed. Results showed the expected interaction, but in the opposite direction: among low hardy women, global attributions predicted stronger endorsement of action.Among high hardy women, specific attributions predicted stronger endorsement of action. Theoretical and practical implications are discussed
Shuttle system ascent aerodynamic and plume heating
The shuttle program provided a challenge to the aerothermodynamicist due to the complexity of the flow field around the vehicle during ascent, since the configuration causes multiple shock interactions between the elements. Wind tunnel tests provided data for the prediction of the ascent design heating environment which involves both plume and aerodynamic heating phenomena. The approach for the heating methodology based on ground test firings and the use of the wind tunnel data to formulate the math models is discussed
Flight-test measurement of the noise reduction of a jet transport delayed flap approach procedure
A delayed flap approach procedure was flight tested using the NASA CV-990 airplane to measure and analyze the noise produced beneath the flight path. Three other types of landing approaches were also flight tested to provide a comparison of the noise reduction benefits to the delayed flap approach. The conventional type of approach was used as a baseline to compare the effectiveness of the other approaches. The decelerating approach is a variation of the delayed flap approach. A detailed comparison of the ground perceived noise generated during the approaches is presented. For this comparison, the measured noise data were normalized to compensate for variations in aircraft weight and winds that occurred during the flight tests. The data show that the reduced flap approach offers some noise reduction, while the delayed flap and decelerating approaches offer significant noise reductions over the conventional approach
Helical automatic approaches of helicopters with microwave landing systems
A program is under way to develop a data base for establishing navigation and guidance concepts for all-weather operation of rotorcraft. One of the objectives is to examine the feasibility of conducting simultaneous rotorcraft and conventional fixed-wing, noninterfering, landing operations in instrument meteorological conditions at airports equipped with microwave landing systems (MLSs) for fixed-wing traffic. An initial test program to investigate the feasibility of conducting automatic helical approaches was completed, using the MLS at Crows Landing near Ames. These tests were flown on board a UH-1H helicopter equipped with a digital automatic landing system. A total of 48 automatic approaches and landings were flown along a two-turn helical descent, tangent to the centerline of the MLS-equipped runway to determine helical light performance and to provide a data base for comparison with future flights for which the helical approach path will be located near the edge of the MLS coverage. In addition, 13 straight-in approaches were conducted. The performance with varying levels of state-estimation system sophistication was evaluated as part of the flight tests. The results indicate that helical approaches to MLS-equipped runways are feasible for rotorcraft and that the best position accuracy was obtained using the Kalman-filter state-estimation with inertial navigation systems sensors
Monitoring the Very-Long-Term Variability of X-ray Sources in the Giant Elliptical Galaxy M87
We report on our search for very-long-term variability (weeks to years) in
X-ray binaries (XRBs) in the giant elliptical galaxy M87. We have used archival
Chandra imaging observations to characterise the long-term variability of 8 of
the brightest members of the XRB population in M87. The peak brightness of some
of the sources exceeded the ultra luminous X-ray source (ULX) threshold
luminosity of ~ 10^{39} erg/s, and one source could exhibit dips or eclipses.
We show that for one source, if it has similar modulation amplitude as in
SS433, then period recoverability analysis on the current data would detect
periodic modulations, but only for a narrow range of periods less than 120
days. We conclude that a dedicated monitoring campaign, with appropriately
defined sampling, is essential if we are to investigate properly the nature of
the long-term modulations such as those seen in Galactic sources.Comment: 19 pages, 19 figures, 1 table, Accepted for publication in MNRAS.
Updated to correct typos in previous versio
Semiclassical description of the kinematically complete experiments
Based on the semiclassical, impact parameter method a theoretical model is
constructed to calculate totally differential cross sections for single
ionization of helium by impact with fast C ions. Good agreement with the
experiment is achieved in the scattering plane, while in the perpendicular
plane a similar structure to that observed experimentally is obtained. The
contribution of different partial waves to the cross section is also
investigated.Comment: 9 pages, 6 figure
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