1,538 research outputs found
Flux-free conductance modulation in a helical Aharonov-Bohm interferometer
A novel conductance oscillation in a twisted quantum ring composed of a
helical atomic configuration is theoretically predicted. Internal torsion of
the ring is found to cause a quantum phase shift in the wavefunction that
describes the electron's motion along the ring. The resulting conductance
oscillation is free from magnetic flux penetrating inside the ring, which is in
complete contrast with the ordinary Aharonov-Bohm effect observed in untwisted
quantum rings.Comment: 10 pages, 4 figure
siRNAs generated by recombinant human Dicer induce specific and significant but target site-independent gene silencing in human cells
Brittleness index of machinable dental materials and its relation to the marginal chipping factor
OBJECTIVES:
The machinability of a material can be measured with the calculation of its brittleness index (BI). It is possible that different materials with different BI could produce restorations with varied marginal integrity. The degree of marginal chipping of a milled restoration can be estimated by the calculation of the marginal chipping factor (CF). The aim of this study is to investigate any possible correlation between the BI of machinable dental materials and the CF of the final restorations.
METHODS:
The CERECTM system was used to mill a wide range of materials used with that system; namely the Paradigm MZ100TM (3M/ESPE), Vita Mark II (VITA), ProCAD (Ivoclar-Vivadent) and IPS e.max CAD (Ivoclar-Vivadent). A Vickers hardness Tester was used for the calculation of BI, while for the calculation of CF the percentage of marginal chipping of crowns prepared with bevelled marginal angulations was estimated.
RESULTS:
The results of this study showed that Paradigm MZ100 had the lowest BI and CF, while IPS e.max CAD demonstrated the highest BI and CF. Vita Mark II and ProCAD had similar BI and CF and were lying between the above materials. Statistical analysis of the results showed that there is a perfect positive correlation between BI and CF for all the materials.
CONCLUSIONS:
The BI and CF could be both regarded as indicators of a material’s machinability. Within the limitations of this study it was shown that as the BI increases so does the potential for marginal chipping, indicating that the BI of a material can be used as a predictor of the CF
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Interseismic coupling and refined earthquake potential on the Hayward-Calaveras fault zone
Interseismic strain accumulation and fault creep is usually estimated from GPS and alignment arrays data, which provide precise but spatially sparse measurements. Here we use interferometric synthetic aperture radar to resolve the interseismic deformation associated with the Hayward and Calaveras Faults (HF and CF) in the East San Francisco Bay Area. The large 1992–2011 SAR data set permits evaluation of short- and long-wavelength deformation larger than 2 mm/yr without alignment of the velocity field to a GPS-based model. Our time series approach in which the interferogram selection is based on the spatial coherence enables deformation mapping in vegetated areas and leads to refined estimates of along-fault surface creep rates. Creep rates vary from 0 ± 2 mm/yr on the northern CF to 14 ± 2 mm/yr on the central CF south of the HF surface junction. We estimate the long-term slip rates by inverting the long-wavelength deformation and the distribution of shallow slip due to creep by inverting the remaining velocity field. This distribution of slip reveals the locations of locked and slowly creeping patches with potential for a M6.8 ± 0.3 on the HF near San Leandro, a M6.6 ± 0.2 on the northern CF near Dublin, a M6.5 ± 0.1 on the HF south of Fremont, and a M6.2 ± 0.2 on the central CF near Morgan Hill. With cascading multisegment ruptures the HF rupturing from Berkeley to the CF junction could produce a M6.9 ± 0.1, the northern CF a M6.6 ± 0.1, the central CF a M6.9 ± 0.2 from the junction to Gilroy, and a joint rupture of the HF and central CF could produce a M7.1 ± 0.1
Diffuse Galactic Soft Gamma-Ray Emission
The Galactic diffuse soft gamma-ray (30-800 keV) emission has been measured
from the Galactic Center by the HIREGS balloon-borne germanium spectrometer to
determine the spectral characteristics and origin of the emission. The
resulting Galactic diffuse continuum is found to agree well with a single
power-law (plus positronium) over the entire energy range, consistent with RXTE
and COMPTEL/CGRO observations at lower and higher energies, respectively. We
find no evidence of spectral steepening below 200 keV, as has been reported in
previous observations. The spatial distribution along the Galactic ridge is
found to be nearly flat, with upper limits set on the longitudinal gradient,
and with no evidence of an edge in the observed region. The soft gamma-ray
diffuse spectrum is well modeled by inverse Compton scattering of interstellar
radiation off of cosmic-ray electrons, minimizing the need to invoke
inefficient nonthermal bremsstrahlung emission. The resulting power requirement
is well within that provided by Galactic supernovae. We speculate that the
measured spectrum provides the first direct constraints on the cosmic-ray
electron spectrum below 300 MeV.Comment: 26 pages, 7 figure, submitted to Ap
Using MailPoet to manage faculty publications alerts and track user engagement
Poster presentation at the 2017 MidContinental Chapter of the Medical Library Association (MCMLA) Annual Meeting, Columbia, Missouri, October 9-11, 2017.OBJECTIVES: Discovering a need for research faculty to understand what their colleagues were researching and where they were publishing, the University of Missouri School of Medicine Research Council wanted a way to provide this information in an easy to read platform. The Research Council contacted the library for a possible solution. This poster will discuss how librarians create monthly email newsletters using the free WordPress plugin, MailPoet to showcase new research. METHODS: Searches are run monthly to identify articles added into the Scopus database in the last 30 days: one for articles in medicine and related fields, and the other for articles in other disciplines. Searches are run and the results are analyzed to highlight the article published in the journal with the highest impact factor. A chart is also created to highlight the journals with the top ten impact factors. With the analysis complete, two WordPress posts are created and published on the library website: one highlights the journal with highest impact factor, and the second post provides an overview of the recent published articles in medicine and related fields, as well as a link to other disciplines. Posts are pulled into a MailPoet newsletter, sent out to the School of Medicine Research Council subscription list. The librarians can track user engagement including who opened the newsletter, and who clicked on the newsletter to go to the original posts. Based on feedback from MailPoet metrics, the librarians have been able to modify the newsletters since January for optimum viewing."--Conference website
Providing service through #MizzouPDF : interlibrary loan/document delivery
Why #MIZZOUPDF? Seeing that #icanhazpdf on social media, we felt we could combat illegal sharing of resources with MizzouPDF, while providing a new means of filling interlibrary loan and 'scan and deliver' requests
Manipulating the Tomonaga-Luttinger exponent by electric field modulation
We establish a theoretical framework for artificial control of the power-law
singularities in Tomonaga-Luttinger liquid states. The exponent governing the
power-law behaviors is found to increase significantly with an increase in the
amplitude of the periodic electric field modulation applied externally to the
system. This field-induced shift in the exponent indicates the tunability of
the transport properties of quasi-one-dimensional electron systems.Comment: 7 pages, 3 figure
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