BRAF V600E is the most common mutation in conventional ameloblastoma (AM) of the mandible. In contrast, maxillary AMs appear to harbor more frequently RAS, FGFR2, or SMO mutations. Unicystic ...ameloblastoma (UAM) is considered a less aggressive variant of ameloblastoma, amenable to more conservative treatment, and classified as a distinct entity. The aim of this study was to characterize the mutation profile of UAM (n = 39) and to compare it to conventional AM (n = 39). The associations between mutation status and recurrence probability were also analyzed. In the mandible, 94% of UAMs (29/31, including 8/8 luminal, 6/8 intraluminal, and 15/15 mural subtypes) and 74% of AMs (28/38) revealed BRAF V600E mutations. Among the BRAF wild-type cases, 1 UAM showed a missense SMO mutation (p.L412F), whereas 2 NRAS (p.Q61R), 2 HRAS (p.Q61R), and 2 FGFR2 (p.C383R) activating mutations were identified in AM. Of the 3 maxillary UAMs, only 1 revealed a BRAF V600E mutation. Taken together, our findings demonstrate high frequency of activating BRAF V600E mutations in both UAM and AM of the mandible. In maxillary UAMs, the BRAF V600E mutation prevalence appears to be lower as was shown for AM previously. It could therefore be argued that UAM and AM are part of the spectrum of the same disease. AMs without BRAF V600E mutations were associated with an increased rate of local recurrence (P = 0.0003), which might indicate that routine mutation testing also has an impact on prognosis.
The past several years have seen the emergence of a standard cosmological model, in which small temperature differences in the cosmic microwave background (CMB) radiation on angular scales of the ...order of a degree are understood to arise from acoustic oscillations in the hot plasma of the early Universe, arising from primordial density fluctuations. Within the context of this model, recent measurements of the temperature fluctuations have led to profound conclusions about the origin, evolution and composition of the Universe. Using the measured temperature fluctuations, the theoretical framework predicts the level of polarization of the CMB with essentially no free parameters. Therefore, a measurement of the polarization is a critical test of the theory and thus of the validity of the cosmological parameters derived from the CMB measurements. Here we report the detection of polarization of the CMB with the Degree Angular Scale Interferometer (DASI). The polarization is deteced with high confidence, and its level and spatial distribution are in excellent agreement with the predictions of the standard theory.
Background Imaging of Cosmic Extragalactic Polarization (BICEP) is a bolometric polarimeter designed to measure the inflationary B-mode polarization of the cosmic microwave background (CMB) at degree ...angular scales. During three seasons of observing at the South Pole (2006 through 2008), BICEP mapped ~2% of the sky chosen to be uniquely clean of polarized foreground emission. Here, we present initial results derived from a subset of the data acquired during the first two years. We present maps of temperature, Stokes Q and U, E and B modes, and associated angular power spectra. We demonstrate that the polarization data are self-consistent by performing a series of jackknife tests. We study potential systematic errors in detail and show that they are sub-dominant to the statistical errors. We measure the E-mode angular power spectrum with high precision at 21 <= ell <= 335, detecting for the first time the peak expected at ell ~ 140. The measured E-mode spectrum is consistent with expectations from a ΛCDM model, and the B-mode spectrum is consistent with zero. The tensor-to-scalar ratio derived from the B-mode spectrum is r = 0.02+0.31 -0.26, or r < 0.72 at 95% confidence, the first meaningful constraint on the inflationary gravitational wave background to come directly from CMB B-mode polarization.
We present the analysis of the complete 3 yr data set obtained with the Degree Angular Scale Interferometer (DASI) polarization experiment, operating from the Amundsen-Scott South Pole research ...station. New data obtained at the end of the 2002 austral winter and throughout the 2003 season were added to the data from which the first detection of polarization of the cosmic microwave background (CMB) radiation was reported. The analysis of the combined data supports, with increased statistical power, all of the conclusions drawn from the initial data set. In particular, the detection of E-mode polarization is increased to the 6.3 sigma confidence level, TE cross-polarization is detected at 2.9 sigma , and B-mode polarization is consistent with zero, with an upper limit well below the level of the detected E-mode polarization. The results are in excellent agreement with the predictions of the cosmological model that has emerged from CMB temperature measurements. The analysis also demonstrates that contamination of the data by known sources of foreground emission is insignificant.
Polarization observations of the cosmic microwave background with the Cosmic Background Imager from September 2002 to May 2004 provide a significant detection of the f-mode polarization and reveal an ...angular power spectrum of polarized emission showing peaks and valleys that are shifted in phase by half a cycle relative to those of the total intensity spectrum. This key agreement between the phase of the observed polarization spectrum and that predicted on the basis of the total intensity spectrum provides support for the standard model of cosmology, in which dark matter and dark energy are the dominant constituents, the geometry is close to flat, and primordial density fluctuations are predominantly adiabatic with a matter power spectrum commensurate with inflationary cosmological models.
We present an improved search for axionlike polarization oscillations in the cosmic microwave background (CMB) with observations from the Keck Array. An all-sky, temporally sinusoidal rotation of CMB ...polarization, equivalent to a time-variable cosmic birefringence, is an observable manifestation of a local axion field and potentially allows a CMB polarimeter to detect axionlike dark matter directly. We describe improvements to the method presented in previous work, and we demonstrate the updated method with an expanded dataset consisting of the 2012–2015 observing seasons. We set limits on the axion-photon coupling constant for mass m in the range 10-23–10-18 eV , which corresponds to oscillation periods on the order of hours to years. Our results are consistent with the background model. For periods between 1 and 30 d ( 1.6×10-21≤m≤4.8×10-20 eV ), the 95%-confidence upper limits on rotation amplitude are approximately constant with a median of 0.27°, which constrains the axion-photon coupling constant to gφγ< ( 4.5×10-12 GeV-1 ) m / ( 10-21 eV ) , if axionlike particles constitute all of the dark matter. More than half of the collected BICEP dataset has yet to be analyzed, and several current and future CMB polarimetry experiments can apply the methods presented here to achieve comparable or superior constraints. In the coming years, oscillation measurements can achieve the sensitivity to rule out unexplored regions of the axion parameter space.
•Presents a recreation value estimate for a protected area network in its entirety.•Recreation values are of a similar order of magnitude to the extractive use values.•Incorporates data from more ...than 62,000 individuals and 728 protected area sites.•Reports on the distribution of recreational value amongst households.•Novel use of pseudo-absence data augmentation improves parameter estimates.
Environmental economists routinely use travel cost methods to value recreational services from protected areas, but a number of limitations remain. First, most travel cost studies focus on a single protected area or a small handful of protected area sites; value estimates that relate to a protected area network across a larger geographic area or jurisdiction are rare. Second, most protected area travel cost studies use on-site sampling techniques that bias value estimates towards those reported by frequent visitors. Values derived from such studies are unlikely to be representative of those held by the broader community, and as such they are of limited utility for strategic land-use planning. We have overcome these limitations to estimate the total value of tourism and recreation for a network of 728 protected areas across 800,000 km2 in New South Wales (NSW) in south-eastern Australia. This is one of the largest studies of its kind undertaken to date, drawing on data from a stratified random phone-survey of more than 62,000 individuals in which interviewers collected detailed information on the number of visits to any and all of the 728 protected areas within NSW. Our study provides new insights into protected area visitation through the use of a random effects ordered logit model, which allows explicit examination of the distribution of recreational value amongst households. Our modelling estimates the value of tourism and recreation services provided by the NSW protected area network at $AUD 3.3 billion per annum. Most of this value accrues to frequent users from within NSW, particularly those from regional areas. The comparative values presented in our study indicate that the recreational services provided by protected areas and other sites can be a similar order of magnitude to, and perhaps even greater than, the extractive uses that are traditionally assigned economic values. It follows that land-use decisions that fail to account for these values are unlikely to optimise societal benefits from land-use allocation.
This work describes the microstructure, indentation toughness, room and high temperature tribological properties of alumina–carbon nanotubes nanocomposites with various contents of carbon nanotubes ...prepared by spark plasma sintering. Materials have been studied by SEM, TEM, Vickers indentation technique on the microhardness and nanohardness testers and, by high temperature ball-on-disk tribometer. The microstructure, CNT dispersion, and fracture surface were studied and wearing mechanisms: fiber pull-out, CNT crushing and formation of transferred film were identified. The addition of 5% CNTs increased the indentation toughness from 3.24MPam1/2 to 4.14MPam1/2. The coefficient of friction of alumina–CNT nanocomposites is approximately three times lower in comparison to the alumina monolithic material due to the lubricating effect of carbon nanotubes during sliding.
We present a search for axionlike polarization oscillations in the cosmic microwave background (CMB) with observations from the Keck Array. A local axion field induces an all-sky, temporally ...sinusoidal rotation of CMB polarization. A CMB polarimeter can thus function as a direct-detection experiment for axionlike dark matter. We develop techniques to extract an oscillation signal. Many elements of the method are generic to CMB polarimetry experiments and can be adapted for other datasets. As a first demonstration, we process data from the 2012 observing season to set upper limits on the axion-photon coupling constant in the mass range 10−21 –10−18 eV, which corresponds to oscillation periods on the order of hours to months. We find no statistically significant deviations from the background model. For periods larger than 24 hr (mass m < 4.8 × 10−20 eV), the median 95% confidence upper limit is equivalent to a rotation amplitude of 0.68°, which constrains the axion-photon coupling constant to gϕγ < (1.1 × 10−11 GeV−1)m/(10−21 eV), if axionlike particles constitute all of the dark matter. The constraints can be improved substantially with data already collected by the BICEP series of experiments. Current and future CMB polarimetry experiments are expected to achieve sufficient sensitivity to rule out unexplored regions of the axion parameter space.
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