A study of two-phase flow in a reduced gravity environment

A test loop was designed and fabricated for observing and measuring pressure drops of two-phase flow in reduced gravity. The portable flow test loop was then tested aboard the NASA-JSC KC135 reduced gravity aircraft. The test loop employed the Sundstrand Two-Phase Thermal Management System (TPTMS) concept which was specially fitted with a clear two-phase return line and condenser cover for flow observation. A two-phase (liquid/vapor) mixture was produced by pumping nearly saturated liquid through an evaporator and adding heat via electric heaters. The quality of the two-phase flow was varied by changing the evaporator heat load. The test loop was operated on the ground before and after the KC135 flight tests to create a one-gravity data base. The ground testing included all the test points run during the reduced gravity testing. Two days of reduced gravity tests aboard the KC135 were performed. During the flight tests, reduced-gravity, one-gravity, and nearly two-gravity accelerations were experienced. Data was taken during the entire flight which provided flow regime and pressure drop data for the three operating conditions. The test results show that two-phase pressure drops and flow regimes can be accurately predicted in zero-gravity

Investigating the Application of Multibeam Sonar and Remotely Operated Vehicles in Fish Population Monitoring on Artificial Reefs

Implementation of ROVs and multibeam imaging sonar in fisheries research has the potential to improve the accuracy and efficiency of current monitoring practices. This study aimed to 1) compare ROV video and diver abundance estimates; 2) evaluate fish length measurement accuracy from sonar; 3) investigate key differentiating sonar characteristics. Results indicate: 1) Diver surveys captured greater diversity of species; survey methods were comparable with regards to conspicuous species (r = 0.089, p = 0.074); 2) Length measurements from multibeam imaging sonar had high predictive power (Rho = 0.998; p \u3c 0.001) of actual standard lengths and; 3) variations between samples were largely due to swim bladder echo, relative position of the target fish, and schooling characteristics. We conclude that 1) ROVs are less apt at observing cryptic species; 2) The Blueview P900-90 sonar can accurately measure fish length; and 3) swim bladder morphology plays an important role in fish identification

fMRI repetition suppression reveals no sensitivity to trait judgments from faces in face perception or theory-of-mind networks

<div><p>The human face cues a wealth of social information, but the neural mechanisms that underpin social attributions from faces are not well known. In the current fMRI experiment, we used repetition suppression to test the hypothesis that populations of neurons in face perception and theory-of-mind neural networks would show sensitivity to faces that cue distinct trait judgments. Although faces were accurately discriminated based on associated traits, our results showed no evidence that face or theory-of-mind networks showed repetition suppression for face traits. Thus, we do not provide evidence for population coding models of face perception that include sensitivity to high and low trait features. Due to aspects of the experimental design, which bolstered statistical power and sensitivity, we have reasonable confidence that we could detect effects of a moderate size, should they exist. The null findings reported here, therefore, add value to models of neural organisation in social perception by showing instances where effects are absent or small. To test the generalisability of our findings, future work should test different types of trait judgment and different types of facial stimuli, in order to further probe the neurobiological bases of impression formation based on facial appearance.</p></div

Evaluation of Ground Nesting by Mourning Doves in Northwestern Oklahoma

Wildlife Conservatio

Plausible responses to the threat of rapid sea-level rise for the Thames Estuary

This paper considers the perceptions and responses of selected stakeholders to a scenarion of rapid rise in sea-level due to the collapse of the West Antarctic ice sheet, which could produce a global rise in sea-level of 5 to 6 metres. Through a process of dialogue involving one-to one interviews and a one-day policy exercise, we addressed influences on decision-making when information is uncertain and our ability to plan, prepare for and implement effective ways of coping with this extreme scenario. Through these interactions we hoped to uncover plausible responses to the scenario and identify potential weaknesses in our current flood management approaches to dealing with such an occurrence. By undertaking this exploratory exercise we hoped to find out whether this was a feasible way to deal with such a low probability but high consequence scenario. It was the process of finding a solution that interested us rather than the technical merits of one solution over another. We were not intending to produce definitive set of recommendations on how to respond but to gain insights into the process of making a decision, specifically what influences it and what assumptions are made.Sea level rise, London

The iconography of Asphyxiophilia: From fantasmatic fetish to forensic fact

This is a post print version of the article. The official published version can be accessed from the link below