3,486 research outputs found
Acylsulfonamide safety-catch linker : promise and limitations for solid-phase oligosaccharide synthesis
Safety-catch linkers are useful for solid-phase oligosaccharide synthesis as they are orthogonal to many common protective groups. A new acylsulfonamide safety-catch linker was designed, synthesized and employed during glycosylations using an automated carbohydrate synthesizer. The analysis of the cleavage products revealed shortcomings for oligosaccharide synthesis
Social media as a venue for personal learning for educators: personal learning networks encourage application of knowledge and skills
Social media sites furnish an online space for a community of practice to create relationships and trust, collaboration and connections, and a personal learning environment. Social networking sites, both public and private, have common elements: member profiles, groups, discussions, and forums. A community of practice brings participants together to share a common interest, to learn from experts, and develop relationships. This dissertation study focused on Apple Distinguished Educators (ADE), a social network, and presents findings on how their participation affected personal learning, how their personal learning impacted their professional practice, and how participation resulted in new network connections and more collaborative work. The findings of this study included gains in personal learning by both male and female educators across experience levels and ages. Overall, males found a higher degree of personal learning than did females. Learning new technology skills and gaining new collaborations were ranked as the greatest personal learning experienced from males while females scored making new network connections and joining in collaborative projects as their greatest gain in personal learning. 54% agreed that participation added to their personal learning. Gains in personal learning laid the foundation for new collaborations. 78% of elementary teachers, 75% of middle schools educators, and 42% of high school educators found collaborative projects as a result of their participation. 63% of university instructors found new connections for collaborative project work. Adding the use of technology to instruction was rated as the highest new strategy gained from participation in the ADE community. The second highest rated new strategy used in instructional practice was using connections to experts. Other strategies added to instructional repertoires included using Web 2.0 tools and online collaboration with other classes and other countries. Several collaborative projects surfaced regularly, including Rock Our World, a music project spanning the globe, and an online global conference, The Global Education Collaborative. Conclusions drawn from this research show that social media provides a personal learning environment. Participants gain new knowledge and skills and as a result add to their professional practice innovative techniques. Study of other social media sites and personal learning is recommended
Six-body Light-Front Tamm-Dancoff approximation and wave functions for the massive Schwinger model
The spectrum of the massive Schwinger model in the strong coupling region is
obtained by using the light-front Tamm-Dancoff (LFTD) approximation up to
including six-body states. We numerically confirm that the two-meson bound
state has a negligibly small six-body component. Emphasis is on the usefulness
of the information about states (wave functions). It is used for identifying
the three-meson bound state among the states below the three-meson threshold.
We also show that the two-meson bound state is well described by the wave
function of the relative motion.Comment: 19 pages, RevTeX, 7 figures are available upon request; Minor errors
have been corrected; Final version to appear in Phys.Rev.
Finite-size effects on a lattice calculation
We study in this paper the finite-size effects of a non-periodic lattice on a
lattice calculation. To this end we use a finite lattice equipped with a
central difference derivative with homogeneous boundary conditions to calculate
the bosonic mass associated to the Schwinger model. We found that the
homogeneous boundary conditions produce absence of fermion doubling and chiral
invariance, but we also found that in the continuum limit this lattice model
does not yield the correct value of the boson mass as other models do. We
discuss the reasons for this and, as a result, the matrix which cause the
fermion doubling problem is identified.Comment: 8 pages, no figures, extended version, five references adde
ERTS-1 applications to Minnesota land use mapping
Land use class definitions that can be operationally employed with ERTS-1 imagery are being developed with the cooperation of personnel from several state, regional, and federal agencies with land management responsibilities within the state and the University of Minnesota. Investigations of urban, extractive, forest, and wetlands areas indicate that it is feasible to subdivide each of these classes into several sub-classes with the use of ERTS-1 images from one or more time periods
Calculation of production and decay of radioisotopes for future irradiation experiments and ion beam facilities
Abstract.: The design of future radioactive ion beam (RIB) facilites requires the forecast of radio isotope inventory after irradiation. At CERN - ISOLDE, we developed a software that estimates the activity of irradiated materials as a function of time dedicated to radioactive waste management. This tool can also be used for licensing procedures, planning of irradiation experiments and the estimation of yield
Sonoluminescing air bubbles rectify argon
The dynamics of single bubble sonoluminescence (SBSL) strongly depends on the
percentage of inert gas within the bubble. We propose a theory for this
dependence, based on a combination of principles from sonochemistry and
hydrodynamic stability. The nitrogen and oxygen dissociation and subsequent
reaction to water soluble gases implies that strongly forced air bubbles
eventually consist of pure argon. Thus it is the partial argon (or any other
inert gas) pressure which is relevant for stability. The theory provides
quantitative explanations for many aspects of SBSL.Comment: 4 page
Dynamics of the Light-Cone Zero Modes: Theta Vacuum of the Massive Schwinger Model
The massive Schwinger model is quantized on the light cone with great care on
the bosonic zero modes by putting the system in a finite (light-cone) spatial
box. The zero mode of survives Dirac's procedure for the constrained
system as a dynamical degree of freedom. After regularization and quantization,
we show that the physical space condition is consistently imposed and relates
the fermion Fock states to the zero mode of the gauge field. The vacuum is
obtained by solving a Schr\"odinger equation in a periodic potential, so that
the theta is understood as the Bloch momentum. We also construct a one-meson
state in the fermion-antifermion sector and obtained the Schr\"odinger equation
for it.Comment: 23 pages, RevTex, no figure
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