2,248 research outputs found
Pediatric Interventional Cardiology: A Specialty Comes of Age
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73435/1/j.1540-8183.1995.tb00574.x.pd
Science and Society in Dialogue About Marker Assisted Selection
Analysis of a European Union funded biotechnology project on plant genomics and marker assisted selection in Solanaceous crops shows that the organization of a dialogue between science and society to accompany technological innovations in plant breeding faces practical challenges. Semi-structured interviews with project participants and a survey among representatives of consumer and other non-governmental organizations show that the professed commitment to dialogue on science and biotechnology is rather shallow and has had limited application for all involved. Ultimately, other priorities tend to prevail because of high workload. The paper recommends including results from previous debates and input from societal groups in the research design phase (prior to communication), to use appropriate media to disseminate information and to make explicit how societal feedback is used in research, in order to facilitate true dialogue between science and society on biotechnology
Type-II Bose-Mott insulators
The Mott insulating state formed from bosons is ubiquitous in solid He-4,
cold atom systems, Josephson junction networks and perhaps underdoped high-Tc
superconductors. We predict that close to the quantum phase transition to the
superconducting state the Mott insulator is not at all as featureless as is
commonly believed. In three dimensions there is a phase transition to a low
temperature state where, under influence of an external current, a
superconducting state consisting of a regular array of 'wires' that each carry
a quantized flux of supercurrent is realized. This prediction of the "type-II
Mott insulator" follows from a field theoretical weak-strong duality, showing
that this 'current lattice' is the dual of the famous Abrikosov lattice of
magnetic fluxes in normal superconductors. We argue that this can be exploited
to investigate experimentally whether preformed Cooper pairs exist in high-Tc
superconductors.Comment: RevTeX, 17 pages, 6 figures, published versio
Strain driven anisotropic magnetoresistance in antiferromagnetic LaSrMnO
We investigate the effects of strain on antiferromagntic (AFM) single crystal
thin films of LaSrMnO (x = 0.6). Nominally unstrained
samples have strong magnetoresistance with anisotropic magnetoresistances (AMR)
of up to 8%. Compressive strain suppresses magnetoresistance but generates AMR
values of up to 63%. Tensile strain presents the only case of a metal-insulator
transition and demonstrates a previously unreported AMR behavior. In all three
cases, we find evidence of magnetic ordering and no indication of a global
ferromagnetic phase transition. These behaviors are attributed to epitaxy
induced changes in orbital occupation driving different magnetic ordering
types. Our findings suggest that different AFM ordering types have a profound
impact on the AMR magnitude and character.Comment: http://dx.doi.org/10.1063/1.489242
Balloon valvuloplasty for critical aortic stenosis in the newborn: Influence of new catheter technology
AbstractBetween 1986 and July 1990, balloon valvuloplasty was attempted in eight newborns (<28 days of age) with isolated critical aortic valve stenosis. Balloon valvuloplasty could not be successfully accomplished in any of the three infants presenting before 1989. Since March 1989, when improved catheter technology became available, all five neonates presenting with critical aortic stenosis were treated successfully by balloon valvuloplasty. A transumbilical approach was utilized in all four infants in whom umbilical artery access could be obtained. One newborn who was 25 days of age underwent transfemoral balloon valvuloplasty.Balloon valvuloplasty was immediately successful in all five newborns, as evidenced by a decrease in valve gradient and improvement in left ventricular function and cardiac output. Peak systolic gradient was reduced by 64% from 69 ± 8 to 25 ± 3 mm Hg (p = 0.005). Left ventricular systolic pressure decreased from 128 ± 9 to 95 ± 9 mm Hg (p = 0.02) and left ventricular end-diastolic pressure decreased from 20 ± 2 to 11 ± 1 mm Hg (p = 0.02). Moderate (2+) aortic regurgitation was documented in two infants after valvuloplasty. The time from first catheter insertion to valve dilation averaged 57 ± 14 min (range 26 to 94) and the median length of the hospital stay was 4 days.With the use of recently available catheters, the transumbilical technique of balloon valvuloplasty can be performed quickly, safely and effectively in the newborn with critical aortic stenosis. It does not require general anesthesia, cardiopulmonary bypass or a left ventricular apical incision and it preserves the femoral arteries for future transcatheter intervention should significant aortic stenosis recur
A Musical instrument in MEMS
In this work we describe a MEMS instrument that resonates at audible frequencies, and with which music can be made. The sounds are generated by mechanical resonators and capacitive displacement sensors. Damping by air scales unfavourably for generating audible frequencies with small devices. Therefore a vacuum of 1.5 mbar is used to increase the quality factor and consequently the duration of the sounds to around 0.25 s. The instrument will be demonstrated during the MME 2010 conference opening, in a musical composition especially made for the occasion
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