1,673 research outputs found

    Different types of atrophy in the prostate with and without adenocarcinoma

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    OBJECTIVES: The purpose of this study was to evaluate, according to a classification proposed by a working group, the extent and type of atrophy lesions in radical prostatectomy specimens obtained from patients with prostatic carcinoma and benign prostatic hyperplasia (BPH), and to compare the prevalence and types of atrophy between two investigated groups. ----- METHODS: Histologic analysis of 1096 slides from 50 patients with carcinoma and 277 slides from 31 patients with BPH was performed to evaluate, according to the new prostatic atrophy classification, the number of foci and type of atrophic lesions. ----- RESULTS: Age, Gleason grade, and TNM showed no significant correlation with the number of proliferative atrophy (PA) and proliferative inflammatory atrophy (PIA) foci (p>0.05). PIA was significantly more frequent in prostates with carcinoma (1.63 vs 1.27 atrophic lesions per slide) (p<0.001), whereas PA displayed an increased frequency in BPH (2.28 vs 0.76 atrophic lesions per slide) (p<0.001). ----- CONCLUSIONS: We confirmed that PA and PIA are common findings in prostates with and without carcinoma, but the question of whether inflammation produces tissue damage and PA or whether some other insult induces the tissue damage and atrophy directly, with inflammation occurring secondarily, is still unresolved

    Three-dimensional charge transport mapping by two-photon absorption edge transient-current technique in synthetic single-crystalline diamond

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    We demonstrate the application of two-photon absorption transient current technique to wide bandgap semiconductors. We utilize it to probe charge transport properties of single-crystal Chemical Vapor Deposition (scCVD) diamond. The charge carriers, inside the scCVD diamond sample, are excited by a femtosecond laser through simultaneous absorption of two photons. Due to the nature of two-photon absorption, the generation of charge carriers is confined in space (3-D) around the focal point of the laser. Such localized charge injection allows to probe the charge transport properties of the semiconductor bulk with a fine-grained 3-D resolution. Exploiting spatial confinement of the generated charge, the electrical field of the diamond bulk was mapped at different depths and compared to an X-ray diffraction topograph of the sample. Measurements utilizing this method provide a unique way of exploring spatial variations of charge transport properties in transparent wide-bandgap semiconductors.Comment: This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. The following article appeared in Applied Physics Letters and may be found at https://doi.org/10.1063/1.509085

    Bias dependence and bistability of radiation defects in silicon

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    Influence of bias on effective dopant concentration in neutron and pion irradiatedp+nn+p^+ - n - n^+ diodes has been measured. Detailed studies of annealing of the bias-induced damagehave revealed three components, with introduction rates from 0.005 to 0.008 cm1^{-1} andannealing time constants ranging from 5 to 1000 hours at 20^\circC. Variation of annealing temperatures yielded activation energies around 1 eV for all the three components. Bistable behavior of radiation damage under bias has been observed and its activation and annealingstudied. The bistable damage was associated to the fastest annealing component of bias-induced damage.Using the parameterization obtained, a prediction for ATLAS SCT operation was made.Bias-induced damage is shown to require an additional 80 V to fully deplete detectors at the end of LHC operation

    Large-scale analysis of cell cycle regulators in urothelial bladder cancer identifies p16 and p27 as potentially useful prognostic markers

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    AIMS: We investigated the value of multiple cell cycle markers for their prognostic impact on overall survival and recurrence-free survival in urothelial carcinoma (UC). METHODS: A tissue microarray consisting of 99 UCs was evaluated for the expression of p53, p16, p21, p27, cyclin D1, cyclin E , Bcl-2, Ki-67 and PCNA. Statistical analysis was performed applying Kaplan-Meier and Cox regression models using receiver operator characteristic curves for determination of markers' cutoffs. RESULTS: Expression above the cutoffs of Ki-67, p53 and p27, particularly in high-grade and early-stage UC, was associated with worse overall survival, while expression of p16 indicated a better outcome in low-grade and low-stage tumors. Recurrence-free survival was better in patients with high-grade UC expressing PCNA, p16 and cyclin E, and low-grade UC expressing Bcl-2 above the cutoffs, but worse in all tumors with high Ki-67. CONCLUSION: Cell cycle deregulation in UC is complex and the prognostic value of the various involved proteins should be differentially regarded with respect to this complexity and other tumor characteristics such as grade and stage. Our results point towards the role of p16- and p27-associated pathways in tumor progression and indicate that, by using standardized approaches for tissue antigen expression, evaluation and cutoff determination, single potentially useful prognostic markers could be identified

    Pathology without microscope: From a projection screen to a virtual slide

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    We have witnessed successive stages since the Seventies in the advancements towards digital pathology. We agree with Dr Pallua et al on the tremendous changes that are taking place in pathology, all leading toward greater role of digitalization in the field of pathology, both in terms of consultation and teaching. In particular, distance teaching using digital pathology will grow into a mainstream mode of pathology teaching, something that has been reinforced by COVID-19

    Evaluating GAIA performances on eclipsing binaries. II. Orbits and stellar parameters for V781 Tau, UV Leo and GK Dra

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    The orbits and physical parameters of three close, double-lined G0 eclipsing binaries have been derived combining H_P, V_T, B_T photometry from the Hipparcos/Tycho mission with 8480-8740 \AA ground-based spectroscopy. The setup is mimicking the photometric and spectroscopic observations that should be obtained by GAIA. The binaries considered here are all of G0 spectral type, but each with its own complications: V781 Tau is an overcontact system with components of unequal temperature, UV Leo shows occasional surface spots and GK Dra contains a delta-Scuti variable. Such peculiarities will be common among binaries to be discovered by GAIA. We find that the values of masses, radii and temperatures for such stars can be derived with a 1-2% accuracy using the adopted GAIA-like observing mode.Comment: accepted for publication in Astronomy and Astrophysics, contains 5 Tables and 3 Figures; correction of an important typ

    Radiation Hardness of Thin Low Gain Avalanche Detectors

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    Low Gain Avalanche Detectors (LGAD) are based on a n++-p+-p-p++ structure where an appropriate doping of the multiplication layer (p+) leads to high enough electric fields for impact ionization. Gain factors of few tens in charge significantly improve the resolution of timing measurements, particularly for thin detectors, where the timing performance was shown to be limited by Landau fluctuations. The main obstacle for their operation is the decrease of gain with irradiation, attributed to effective acceptor removal in the gain layer. Sets of thin sensors were produced by two different producers on different substrates, with different gain layer doping profiles and thicknesses (45, 50 and 80 um). Their performance in terms of gain/collected charge and leakage current was compared before and after irradiation with neutrons and pions up to the equivalent fluences of 5e15 cm-2. Transient Current Technique and charge collection measurements with LHC speed electronics were employed to characterize the detectors. The thin LGAD sensors were shown to perform much better than sensors of standard thickness (~300 um) and offer larger charge collection with respect to detectors without gain layer for fluences <2e15 cm-2. Larger initial gain prolongs the beneficial performance of LGADs. Pions were found to be more damaging than neutrons at the same equivalent fluence, while no significant difference was found between different producers. At very high fluences and bias voltages the gain appears due to deep acceptors in the bulk, hence also in thin standard detectors

    SN 2007od: A Type IIP SN with Circumstellar Interaction

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    SN 2007od exhibits characteristics that have rarely been seen in a Type IIP supernova (SN). Optical V band photometry reveals a very steep brightness decline between the plateau and nebular phases of ~4.5 mag, likely due to SN 2007od containing a low mass of 56Ni. The optical spectra show an evolution from normal Type IIP with broad Halpha emission, to a complex, four component Halpha emission profile exhibiting asymmetries caused by dust extinction after day 232. This is similar to the spectral evolution of the Type IIn SN 1998S, although no early-time narrow (~200 km s-1) Halpha component was present in SN 2007od. In both SNe, the intermediate-width Halpha emission components are thought to arise in the interaction between the ejecta and its circumstellar medium (CSM). SN 2007od also shows a mid-IR excess due to new dust. The evolution of the Halpha profile and the presence of the mid-IR excess provide strong evidence that SN 2007od formed new dust before day 232. Late-time observations reveal a flattening of the visible lightcurve. This flattening is a strong indication of the presence of a light echo, which likely accounts for much of the broad, underlying Halpha component seen at late-times. We believe the multi-peaked Halpha emission is consistent with the interaction of the ejecta with a circumstellar ring or torus (for the inner components at \pm1500 km s-1), and a single blob or cloud of circumstellar material out of the plane of the CSM ring (for the outer component at -5000 km s-1). The most probable location for the formation of new dust is in the cool dense shell created by the interaction between the expanding ejecta and its CSM. Monte Carlo radiative transfer modeling of the dust emission from SN 2007od implies that up to 4x 10-4Msun of new dust has formed. This is similar to the amounts of dust formed in other CCSNe such as SNe 1999em, 2004et, and 2006jc.Comment: 35 pages, 6 figures. Accepted for publication in Ap
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