1,802 research outputs found
A coral reef as an analogical model to promote collaborative learning on cultural and ethnic diversity in science
An exercise designed to engage students in critical thinking and active conversation about gender, diversity, and ethnicity in science is described. First semester college science students frequently do not realize that individual scholarship is an integral component of global scholarship and that scientific progress stems from the scholarly contributions of numerous individuals. The described exercise initially uses a collage of a coral reef—chosen both for its visual impact and because it is an excellent model of diversity—highlighting various aspects of life on a reef. This is followed by a trawl of library resources to enable the development of a chronology of significant contributions and practices in the field of medicine and the identification of historical and contemporary scholars and practitioners by race, cultural heritage, and gender
Apparatus for welding torch angle and seam tracking control Patent
Computer controlled apparatus for maintaining welding torch angle and velocity during seam trackin
Photographic techniques for enhancing ERTS MSS data for geologic information
Satellite multispectral black-and-white photographic negatives of Luna County, New Mexico, obtained by ERTS on 15 August and 2 September 1973, were precisely reprocessed into positive images and analyzed in an additive color viewer. In addition, an isoluminous (uniform brightness) color rendition of the image was constructed. The isoluminous technique emphasizes subtle differences between multispectral bands by greatly enhancing the color of the superimposed composite of all bands and eliminating the effects of brightness caused by sloping terrain. Basaltic lava flows were more accurately displayed in the precision processed multispectral additive color ERTS renditions than on existing state geological maps. Malpais lava flows and small basaltic occurrences not appearing on existing geological maps were identified in ERTS multispectral color images
Path to the Theoretical Luminosity Precision Requirement for the FCC-ee (and ILC)
We present pathways to the required theoretical precision for the luminosity
targeted by the FCC-ee precision studies. We put the discussion in context by
reviewing briefly the situation at the time of LEP. We then present the current
status and routes to the desired 0.01\% targeted by the FCC-ee (as well as by
the ILC).Comment: 6 pages, 2 tables; talk presented at the International Workshop on
Future Linear Colliders (LCWS2018), Arlington, Texas, 22-26 October 2018.
C18-10-22; typos corrected; misprint correcte
Acetylation of albumin by low doses of aspirin
Aspirin has a variety of pharmacologic actions, which are expressed at
different doses of the drug. An effect on platelet function occurs at very
low doses of aspirin (1,2). Indeed, a large number of clinical trials have
been carried out to assess whether low to moderate doses of aspirin (180 to
1500 mg per day) taken prophylactically will affect the natural history of a
variety of diseases in which thrombosis is thought to play a role (3)
Space Technology Presentation: DARPA Phoenix Industry Day 2011
Space technology programs approach and future goals presentation by NASA ARC CCT
Liquid-immersible electrostatic ultrasonic transducer
A broadband megahertz range electrostatic acoustic transducer for use in a liquid environment is described. A liquid tight enclosure includes a metallic conducting membrane as part of its outside surface and has a means inside the liquid tight enclosure for applying a tension to the membrane and for mounting an electrode such that the flat end of the electrode is aproximately parallel to the membrane. The invention includes structure and a method for ensuring that the membrane and the flat end of the electrode are exactly parallel and a fixed predetermined distance from each other
New Results on Precision Studies of Heavy Vector Boson Physics
We present new results for two important heavy vector boson physics
processes: (1), virtual corrections to hard bremsstrahlung which are relevant
to precision predictions for the radiative return process in Z boson production
at and beyond LEP2 energies ; and, (2), electric charge screening effects in
single W production with finite p_T, multiple photon radiation in high energy
collider physics processes. In both cases we show that we improve the
respective precision tag significantly. Phenomenological implications are
discussed.Comment: 5 pages, 2 figures; to appear in Proc. DPF200
Regulation of Gut and Heart Left–Right Asymmetry by Context-Dependent Interactions between Xenopus Lefty and BMP4 Signaling
AbstractThe Lefty subfamily of TGFβ signaling molecules has been implicated in early development in mouse, zebrafish, and chick. Here, we show that Xenopus lefty (Xlefty) is expressed both bilaterally in symmetric midline domains and unilaterally in left lateral plate mesoderm and anterior dorsal endoderm. To examine the roles of Xlefty in left–right development, we created a system for scoring gut asymmetry and examined the effects of unilateral Xlefty misexpression on gut development, heart development, and Xnr-1 and XPitx2 expression. In contrast to the unilateral effects of Vg1, Activin, Nodal, or BMPs, targeted expression of Xlefty in either the left or the right side of Xenopus embryos randomized the direction of heart looping, gut coiling, and left–right positioning of the gut and downregulated the asymmetric expression of Xnr-1 and XPitx2. It is currently thought that Lefty proteins act as feedback inhibitors of Nodal signaling. However, this would not explain the effects of right-sided Xlefty misexpression. Here, we show that Xlefty interacts with the signaling pathways of other members of the TGFβ family during left–right development. Results from coexpression of Xlefty and Vg1 indicate that Xlefty can nullify the effects of Vg1 ectopic expression and that Xlefty is downstream of left-sided Vg1 signaling. Results from coexpression of Xlefty and XBMP4 indicate that XLefty and XBMP4 interact both synergistically and antagonistically in a context-dependent manner. We propose a model in which interactions of Xlefty with multiple members of the TGFβ family enhance the differences between the right-sided BMP/ALK2/Smad pathway and the left-sided Vg1/anti-BMP/Nodal pathway, leading to left–right morphogenesis of the gut and heart
- …