Social Norms: Do We Love Norms Too Much?

Social norms are often cited as the cause of many social phenomena, especially as an explanation for prosocial family and relationship behaviors. And yet maybe we love the idea of social norms too much, as suggested by our failure to subject them to rigorous test. Compared to the detail in social norms theoretical orientations, there is very little detail in tests of normative theories. To provide guidance to researchers who invoke social norms as explanations, we catalog normative orientations that have been proposed to account for consistent patterns of action. We call on researchers to conduct tests of normative theories and the processes such theories assert

Leadership in Student Distance Education Teams

Interactive video technology has become a widely used medium for education. A prominent implementation of this technology, interactive distance learning, involves groups of students at local and remote sites connected by audio and video teleconferencing. This approach has made the task of delivering vital undergraduate and graduate engineering courses to distributed audiences much easier. As this approach has permeated more curricula, distance education instructors have increasingly assigned projects that require distance learners to work together as an element of the final course grade. This trend presents an interesting opportunity for researchers to understand the nature of interactions among course participants involved in project teams. This paper presents the results of an investigation of project leadership behaviors in the distance learning environment. Surveys were administered via online protocol to fifty-three students, comprising nineteen project teams. Results indicate that those teams led by individuals who clarified roles and task requirements, and recognized the strengths and individual needs of teams members performed better on their assigned tasks. Implications for instructors utilizing project teams in distance education, as well as traditional teams where communication technology (e.g., email) is highly relied upon, are presented

Subscale Flight Testing for Aircraft Loss of Control: Accomplishments and Future Directions

Subscale flight-testing provides a means to validate both dynamic models and mitigation technologies in the high-risk flight conditions associated with aircraft loss of control. The Airborne Subscale Transport Aircraft Research (AirSTAR) facility was designed to be a flexible and efficient research facility to address this type of flight-testing. Over the last several years (2009-2011) it has been used to perform 58 research flights with an unmanned, remotely-piloted, dynamically-scaled airplane. This paper will present an overview of the facility and its architecture and summarize the experimental data collected. All flights to date have been conducted within visual range of a safety observer. Current plans for the facility include expanding the test volume to altitudes and distances well beyond visual range. The architecture and instrumentation changes associated with this upgrade will also be presented

A Model For the Formation of High Density Clumps in Proto-Planetary Nebulae

The detection of NaCl at large radii in the Egg Nebula, CRL 2688, requires densities of 10^7 - 10^8 cm^-3 in a thick shell of r ~ a few X 10^17 cm. To explain these results, a mechanism is needed for producing high densities at a considerable distance from the central star. In two dimensional simulations of the interaction of the fast wind with an ambient medium, the material becomes thermally unstable. The resulting clumps can achieve the requisite conditions for NaCl excitation. We present 2D models with simple physics as proof-of-principle calculations to show that the clumping behavior is robust. Clumping is a natural outcome of cooling in the colliding wind model and comparable to that inferred from observations.Comment: 12 pages, 3 figures. Accepted for publication in the Astrophysical Journal Letter

Toward Automation of the Supine Pressor Test for Preeclampsia

Preeclampsia leads to increased risk of morbidity and mortality for both mother and fetus. Most previous studies have largely neglected mechanical compression of the left renal vein by the gravid uterus as a potential mechanism. In this study, we first used a murine model to investigate the pathophysiology of left renal vein constriction. The results indicate that prolonged renal vein stenosis after 14 days can cause renal necrosis and an increase in blood pressure (BP) of roughly 30 mmHg. The second part of this study aimed to automate a diagnostic tool, known as the supine pressor test (SPT), to enable pregnant women to assess their preeclampsia development risk. A positive SPT has been previously defined as an increase of at least 20 mmHg in diastolic BP when switching between left lateral recumbent and supine positions. The results from this study established a baseline BP increase between the two body positions in nonpregnant women and demonstrated the feasibility of an autonomous SPT in pregnant women. Our results demonstrate that there is a baseline increase in BP of roughly 10-14 mmHg and that pregnant women can autonomously perform the SPT. Overall, this work in both rodents and humans suggests that (1) stenosis of the left renal vein in mice leads to elevation in BP and acute renal failure, (2) nonpregnant women experience a baseline increase in BP when they shift from left lateral recumbent to supine position, and (3) the SPT can be automated and used autonomously

Dust Explosions and Collapsed Ductwork

PresentationOne of the more obvious consequences of a dust deflagration inside process equipment or a structure is the mechanical damage caused by shock (compression) waves. This overpressure damage is revealed through the displacement of equipment, the outward deformation or rupture of enclosures constructed of ductile materials, or the projection of missiles. However, a different type of damage is sometimes observed in the ductwork connecting process equipment. In particular, the ductwork is collapsed as if it were subjected to an external, rather than an internal pressure. The phenomenon that causes this collapse of thin-walled conduit is a gas dynamic process called an expansion wave. When a dust deflagration travels through a conduit, it accelerates and causing a rise in pressure. When the dust deflagration is vented (say through a deflagration vent), the discharge of the high pressure combustion products causes the formation of an expansion wave that travels in the reverse direction from the vent backwards. The expansion wave causes the pressure in the ductwork to fall below atmospheric pressure. The sub-atmospheric pressure, in turn, causes the ductwork to fail by buckling. In this study, we examine the gas dynamics of the expansion wave, demonstrate how to calculate the degree of pressure drop caused by the expansion wave, and illustrate the concept with case studies of dust explosions

Enhancing spatial detection accuracy for syndromic surveillance with street level incidence data

<p>Abstract</p> <p>Background</p> <p>The Department of Defense Military Health System operates a syndromic surveillance system that monitors medical records at more than 450 non-combat Military Treatment Facilities (MTF) worldwide. The Electronic Surveillance System for Early Notification of Community-based Epidemics (ESSENCE) uses both temporal and spatial algorithms to detect disease outbreaks. This study focuses on spatial detection and attempts to improve the effectiveness of the ESSENCE implementation of the spatial scan statistic by increasing the spatial resolution of incidence data from zip codes to street address level.</p> <p>Methods</p> <p>Influenza-Like Illness (ILI) was used as a test syndrome to develop methods to improve the spatial accuracy of detected alerts. Simulated incident clusters of various sizes were superimposed on real ILI incidents from the 2008/2009 influenza season. Clusters were detected using the spatial scan statistic and their displacement from simulated loci was measured. Detected cluster size distributions were also evaluated for compliance with simulated cluster sizes.</p> <p>Results</p> <p>Relative to the ESSENCE zip code based method, clusters detected using street level incidents were displaced on average 65% less for 2 and 5 mile radius clusters and 31% less for 10 mile radius clusters. Detected cluster size distributions for the street address method were quasi normal and sizes tended to slightly exceed simulated radii. ESSENCE methods yielded fragmented distributions and had high rates of zero radius and oversized clusters.</p> <p>Conclusions</p> <p>Spatial detection accuracy improved notably with regard to both location and size when incidents were geocoded to street addresses rather than zip code centroids. Since street address geocoding success rates were only 73.5%, zip codes were still used for more than one quarter of ILI cases. Thus, further advances in spatial detection accuracy are dependant on systematic improvements in the collection of individual address information.</p