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Global morphogenetic flow is accurately predicted by the spatial distribution of myosin motors.
During embryogenesis tissue layers undergo morphogenetic flow rearranging and folding into specific shapes. While developmental biology has identified key genes and local cellular processes, global coordination of tissue remodeling at the organ scale remains unclear. Here, we combine in toto light-sheet microscopy of the Drosophila embryo with quantitative analysis and physical modeling to relate cellular flow with the patterns of force generation during the gastrulation process. We find that the complex spatio-temporal flow pattern can be predicted from the measured meso-scale myosin density and anisotropy using a simple, effective viscous model of the tissue, achieving close to 90% accuracy with one time dependent and two constant parameters. Our analysis uncovers the importance of a) spatial modulation of myosin distribution on the scale of the embryo and b) the non-locality of its effect due to mechanical interaction of cells, demonstrating the need for the global perspective in the study of morphogenetic flow
Social competence in pediatric brain tumor survivors: application of a model from social neuroscience and developmental psychology.
Pediatric brain tumor (BT) survivors are at risk for psychosocial late effects across many domains of functioning, including neurocognitive and social. The literature on the social competence of pediatric BT survivors is still developing and future research is needed that integrates developmental and cognitive neuroscience research methodologies to identify predictors of survivor social adjustment and interventions to ameliorate problems. This review discusses the current literature on survivor social functioning through a model of social competence in childhood brain disorder and suggests future directions based on this model. Interventions pursuing change in survivor social adjustment should consider targeting social ecological factors
Technical Findings, Lessons Learned, and Recommendations Resulting from the Helios Prototype Vehicle Mishap
The Helios Prototype was originally planned to be two separate vehicles, but because of resource limitations only one vehicle was developed to demonstrate two missions. The vehicle consisted of two configurations, one for each mission. One configuration, designated HP01, was designed to operate at extremely high altitudes using batteries and high-efficiency solar cells spread across the upper surface of its 247-foot wingspan. On August 13, 2001, the HP01 configuration reached an altitude of 96,863 feet, a world record for sustained horizontal flight by a winged aircraft. The other configuration, designated HP03, was designed for long-duration flight. The plan was to use the solar cells to power the vehicle's electric motors and subsystems during the day and to use a modified commercial hydrogen-air fuel cell system for use during the night. The aircraft design used wing dihedral, engine power, elevator control surfaces, and a stability augmentation and control system to provide aerodynamic stability and control. At about 30 minutes into the second flight of HP03, the aircraft encountered a disturbance in the way of turbulence and morphed into an unexpected, persistent, high dihedral configuration. As a result of the persistent high dihedral, the aircraft became unstable in a very divergent pitch mode in which the airspeed excursions from the nominal flight speed about doubled every cycle of the oscillation. The aircraft s design airspeed was subsequently exceeded and the resulting high dynamic pressures caused the wing leading edge secondary structure on the outer wing panels to fail and the solar cells and skin on the upper surface of the wing to rip away. As a result, the vehicle lost its ability to maintain lift, fell into the Pacific Ocean within the confines of the U.S. Navy's Pacific Missile Range Facility, and was destroyed. This paper describes the mishap and its causes, and presents the technical recommendations and lessons learned for improving the design, analysis, and testing methods and techniques required for this class of vehicle
The Lantern Vol. 56, No. 1, Fall 1989
• Spider Silk • Cattle Prods and Prodigies • Hooligans • Japan Night • Closed Captioned for the Emotionally Impaired • On Reading Ellison\u27s King of the Bingo Game • Breakfast Talk • Thoughts in a Boring Bed • Therapy • Maria\u27s Room • The Poet, Unsuccessful Once Again • Words in a Restaurant • Their Way • Maternity • Hell in a Nut Shell • Transformers • What Would Mozart Hear? • A Single Sestinahttps://digitalcommons.ursinus.edu/lantern/1135/thumbnail.jp
The Lantern Vol. 55, No. 1, Fall 1988
• The Third Grade Gorilla • Friend, I Am Not Yet A Poet • Twisted • The Final Journey • Ritu Miltonis • Hearthside • The Ogre • O Indestructible Everlasting • December 1, 1988 • Our Church • Louise • Gazebo For Learned Women • Hanging Mirror • Of Football and Flashlights • The Ragged Brown Peasant • Judgement of the Serpent • Sidewalk Wars • I Guess That\u27s Why I Went Awayhttps://digitalcommons.ursinus.edu/lantern/1133/thumbnail.jp
The Lantern Vol. 54, No. 1, Fall 1987
• Darkside • Reflections on a Subway Ride • Demand for Love • Music Man • Something Wild • The Nice Guy\u27s Story • The Picnic • Internalize • Days When You Feel Like Wonder Bread • II • A Tear • In Pursuit of Beauty • A Walk Down Sycamore Lane • A Wish • Sins of Omission • Pessimism • And the Sky Cracked • The Clock Strikes • Invinciblehttps://digitalcommons.ursinus.edu/lantern/1131/thumbnail.jp
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