3,805 research outputs found
Josephson junctions in thin and narrow rectangular superconducting strips
I consider a Josephson junction crossing the middle of a thin rectangular
superconducting strip of length L and width W subjected to a perpendicular
magnetic induction B. I calculate the spatial dependence of the gauge-invariant
phase difference across the junction and the resulting B dependence of the
critical current Ic(B).Comment: 4 pages, 6 figures, revised following referee's comment
Violence Prevention: Reaching Adolescents with the Message
To identify an effective medium for communicating with adolescents in a large-scale, cost-effective violence prevention program.
A set of youth violence prevention programs was established at The Stamford Hospital, a level II trauma center. The traveling version of the program was presented to middle school students in four parts: 1) a rap music video created by our violence prevention staff, 2) a facilitated discussion about dealing with anger, 3) a video of a trauma resuscitation in our emergency department, and 4) a commercial video of a teenage boy paralyzed after a gunshot wound. A written questionnaire with a five-point rating scale (1 to 5) was used to survey the audience 1 month after the program. The survey assessed the respondents\u27 recall of each part of the program and the perceptions of the value of each part in identifying the problem of violence and reducing violent behavior.
Results: Of 99 respondents, the highest ratings for retention, problem identification, and impact were given to the commercial video (combined average category ranking of 11.394) and the rap music video (11.182). The trauma resuscitation video and the discussion of anger were ranked as being less effective (10.253 and 9.383, respectively). The audience seemed to comprehend the main point of the program and ranked the program, as a whole, higher than any of the parts when measured by success at problem identification and impact.
Effective communication with adolescents is possible through many avenues. Children of the video age respond well to visual material. A violence prevention program should incorporate effective multimedia presentations. A variety of methods hi combination proves to be most effective
Implications Of The Caacb Virus Contamination In Biomanufacturing Project For Cell Therapy Manufacturers
Adventitious agent contamination of cell culture-based biomanufacturing operations for the production of protein and monoclonal antibody biotherapeutics are infrequent, but when they do occur, they are very costly, impact manufacturing operations, and can potentially impact patient safety and product supply. In response to this need, the MIT Consortium on Adventitious Agent Contamination in Biomanufacturing (CAACB) began the confidential collection and analysis of industry-wide viral contamination data with an emphasis on “lessons learned”. This presentation will cover the learnings from this study, including identified industry risks and best practices to mitigate those risks. Some of the key findings which have significant implications to the emerging cell therapy industry are:
1) Raw materials, including non-animal-based raw materials, may be a potential source of viral contamination and stringent raw material testing and vendor selection and auditing programs are critical.
2) Traditional viral tests, including in vitro testing and PCR, have contributed to false-positive events, which may take extended times to resolve prior to release of raw materials, process intermediates, or final product.
3) The time frames needed for viral testing in general, and for investigation of positive viral tests, can range from weeks to months, and are not compatible with the requirements for near real-time release testing for some cell therapy products.
4) Viral testing programs, and potential investigations of positive results, are quite expensive, and application to the autologous cell therapy space will be challenging
Selective functionalization of carbon nanotubes
The present invention is directed toward methods of selectively functionalizing carbon nanotubes of a specific type or range of types, based on their electronic properties, using diazonium chemistry. The present invention is also directed toward methods of separating carbon nanotubes into populations of specific types or range(s) of types via selective functionalization and electrophoresis, and also to the novel compositions generated by such separations
Methods for selective functionalization and separation of carbon nanotubes
The present invention is directed toward methods of selectively functionalizing carbon nanotubes of a specific type or range of types, based on their electronic properties, using diazonium chemistry. The present invention is also directed toward methods of separating carbon nanotubes into populations of specific types or range(s) of types via selective functionalization and electrophoresis, and also to the novel compositions generated by such separations
The onset of circulation triggers a metabolic switch required for endothelial to hematopoietic transition
Hematopoietic stem cells (HSCs) emerge during development from the vascular wall of the main embryonic arteries. The onset of circulation triggers several processes that provide critical external factors for HSC generation. Nevertheless, it is not fully understood how and when the onset of circulation affects HSC emergence. Here we show that in Ncx1-/- mouse embryos devoid of circulation the HSC lineage develops until the phenotypic pro-HSC stage. However, these cells reside in an abnormal microenvironment, fail to activate the hematopoietic program downstream of Runx1, and are functionally impaired. Single-cell transcriptomics shows that during the endothelial-to-hematopoietic transition, Ncx1-/- cells fail to undergo a glycolysis to oxidative phosphorylation metabolic switch present in wild-type cells. Interestingly, experimental activation of glycolysis results in decreased intraembryonic hematopoiesis. Our results suggest that the onset of circulation triggers metabolic changes that allow HSC generation to proceed
The Herschel Virgo Cluster Survey. IX. Dust-to-gas mass ratio and metallicity gradients in four Virgo spiral galaxies
Using Herschel data from the Open Time Key Project the Herschel Virgo Cluster
Survey (HeViCS), we investigated the relationship between the metallicity
gradients expressed by metal abundances in the gas phase as traced by the
chemical composition of HII regions, and in the solid phase, as traced by the
dust-to-gas mass ratio. We derived the radial gradient of the dust-to-gas mass
ratio for all galaxies observed by HeViCS whose metallicity gradients are
available in the literature. They are all late type Sbc galaxies, namely
NGC4254, NGC4303, NGC4321, and NGC4501. We examined different dependencies on
metallicity of the CO-to-H conversion factor (\xco), used to transform the
CO observations into the amount of molecular hydrogen. We found that in
these galaxies the dust-to-gas mass ratio radial profile is extremely sensitive
to choice of the \xco\ value, since the molecular gas is the dominant component
in the inner parts. We found that for three galaxies of our sample, namely
NGC4254, NGC4321, and NGC4501, the slopes of the oxygen and of the dust-to-gas
radial gradients agree up to 0.6-0.7R using \xco\ values in the
range 1/3-1/2 Galactic \xco. For NGC4303 a lower value of \xco
10 is necessary. We suggest that such low \xco\ values might be due to a
metallicity dependence of \xco (from close to linear for NGC4254, NGC4321, and
NGC4501 to superlinear for NGC4303), especially in the radial regions
R0.6-0.7R where the molecular gas dominates. On the other hand, the
outer regions, where the atomic gas component is dominant, are less affected by
the choice of \xco, and thus we cannot put constraints on its value.Comment: 13 pages, 8 figures, A&A accepte
Gravitational Waves From Known Pulsars: Results From The Initial Detector Era
We present the results of searches for gravitational waves from a large selection of pulsars using data from the most recent science runs (S6, VSR2 and VSR4) of the initial generation of interferometric gravitational wave detectors LIGO (Laser Interferometric Gravitational-wave Observatory) and Virgo. We do not see evidence for gravitational wave emission from any of the targeted sources but produce upper limits on the emission amplitude. We highlight the results from seven young pulsars with large spin-down luminosities. We reach within a factor of five of the canonical spin-down limit for all seven of these, whilst for the Crab and Vela pulsars we further surpass their spin-down limits. We present new or updated limits for 172 other pulsars (including both young and millisecond pulsars). Now that the detectors are undergoing major upgrades, and, for completeness, we bring together all of the most up-to-date results from all pulsars searched for during the operations of the first-generation LIGO, Virgo and GEO600 detectors. This gives a total of 195 pulsars including the most recent results described in this paper.United States National Science FoundationScience and Technology Facilities Council of the United KingdomMax-Planck-SocietyState of Niedersachsen/GermanyAustralian Research CouncilInternational Science Linkages program of the Commonwealth of AustraliaCouncil of Scientific and Industrial Research of IndiaIstituto Nazionale di Fisica Nucleare of ItalySpanish Ministerio de Economia y CompetitividadConselleria d'Economia Hisenda i Innovacio of the Govern de les Illes BalearsNetherlands Organisation for Scientific ResearchPolish Ministry of Science and Higher EducationFOCUS Programme of Foundation for Polish ScienceRoyal SocietyScottish Funding CouncilScottish Universities Physics AllianceNational Aeronautics and Space AdministrationOTKA of HungaryLyon Institute of Origins (LIO)National Research Foundation of KoreaIndustry CanadaProvince of Ontario through the Ministry of Economic Development and InnovationNational Science and Engineering Research Council CanadaCarnegie TrustLeverhulme TrustDavid and Lucile Packard FoundationResearch CorporationAlfred P. Sloan FoundationAstronom
Measurement of the lepton charge asymmetry in W-boson decays produced in p-pbar collisions
We describe a measurement of the charge asymmetry of leptons from W boson
decays in the rapidity range 0 enu, munu events from
110+/-7 pb^{-1}of data collected by the CDF detector during 1992-95. The
asymmetry data constrain the ratio of d and u quark momentum distributions in
the proton over the x range of 0.006 to 0.34 at Q2 \approx M_W^2. The asymmetry
predictions that use parton distribution functions obtained from previously
published CDF data in the central rapidity region (0.0<|y_l|<1.1) do not agree
with the new data in the large rapidity region (|y_l|>1.1).Comment: 13 pages, 3 tables, 1 figur
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