Effect of substrate temperature on structural and morphological parameters of ZnTe thin films

Vacuum evaporated thin films of Zinc Telluride (ZnTe) of 5000 Å thickness have been deposited on glass substrates at different substrate temperatures (303 K, 373 K, 448 K). Structural parameters were obtained using XRD analysis. Atomic Force Microscope (AFM) in non-contact mode has been used to study the surface morphological properties of the deposited thin films. The results obtained from structural and surface morphological studies have been correlated and it is found that the films deposited at higher substrate temperatures possess increasingly good crystallinity and smoother surfaces. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/930

A wide search for obscured active galactic nuclei using XMM-Newton and WISE

Heavily obscured and Compton-thick active galactic nuclei (AGNs) are missing even in the deepest X-ray surveys, and indirect methods are required to detect them. Here we use a combination of the XMM–Newton serendipitous X-ray survey with the optical Sloan Digital Sky Survey (SDSS), and the infrared WISE all-sky survey in order to check the efficiency of the low X-ray-to-infrared luminosity selection method in finding heavily obscured AGNs. We select the sources which are detected in the hard X-ray band (2–8 keV), and also have a redshift determination (photometric or spectroscopic) in the SDSS catalogue. We match this sample with the WISE catalogue, and fit the spectral energy distributions of the 2844 sources which have three, or more, photometric data points in the infrared. We then select the heavily obscured AGN candidates by comparing their 12 μm luminosity to the observed 2–10 keV X-ray luminosity and the intrinsic relation between the X-ray and the mid-infrared luminosities. With this approach, we find 20 candidate heavily obscured AGNs and we then examine their X-ray and optical spectra. Of the 20 initial candidates, we find nine (64 per cent; out of the 14, for which X-ray spectra could be fitted) based on the X-ray spectra, and seven (78 per cent; out of the nine detected spectroscopically in the SDSS) based on the [O III] line fluxes. Combining all criteria, we determine the final number of heavily obscured AGNs to be 12–19, and the number of Compton-thick AGNs to be 2–5, showing that the method is reliable in finding obscured AGNs, but not Compton thick. However, those numbers are smaller than what would be expected from X-ray background population synthesis models, which demonstrates how the optical–infrared selection and the scatter of the Lx-LMIR relation limit the efficiency of the method. Finally, we test popular obscured AGN selection methods based on mid-infrared colours, and find that the probability of an AGN to be selected by its mid-infrared colours increases with the X-ray luminosity. The (observed) X-ray luminosities of heavily obscured AGNs are relatively low (L2−10keV<1044ergs−1), even though most of them are located in the ‘quasi stellar object (QSO) locus’. However, a selection scheme based on a relatively low X-ray luminosity and mid-infrared colours characteristic of QSOs would not select ∼25 per cent of the heavily obscured AGNs of our sample

Use of Coronary Computed Tomographic Angiography to guide management of patients with coronary disease

Background In a prospective, multicenter, randomized controlled trial, 4,146 patients were randomized to receive standard care or standard care plus coronary computed tomography angiography (CCTA). Objectives The purpose of this study was to explore the consequences of CCTA-assisted diagnosis on invasive coronary angiography, preventive treatments, and clinical outcomes. Methods In post hoc analyses, we assessed changes in invasive coronary angiography, preventive treatments, and clinical outcomes using national electronic health records. Results Despite similar overall rates (409 vs. 401; p = 0.451), invasive angiography was less likely to demonstrate normal coronary arteries (20 vs. 56; hazard ratios [HRs]: 0.39 [95% confidence interval (CI): 0.23 to 0.68]; p < 0.001) but more likely to show obstructive coronary artery disease (283 vs. 230; HR: 1.29 [95% CI: 1.08 to 1.55]; p = 0.005) in those allocated to CCTA. More preventive therapies (283 vs. 74; HR: 4.03 [95% CI: 3.12 to 5.20]; p < 0.001) were initiated after CCTA, with each drug commencing at a median of 48 to 52 days after clinic attendance. From the median time for preventive therapy initiation (50 days), fatal and nonfatal myocardial infarction was halved in patients allocated to CCTA compared with those assigned to standard care (17 vs. 34; HR: 0.50 [95% CI: 0.28 to 0.88]; p = 0.020). Cumulative 6-month costs were slightly higher with CCTA: difference $462 (95$303 to $621). Conclusions In patients with suspected angina due to coronary heart disease, CCTA leads to more appropriate use of invasive angiography and alterations in preventive therapies that were associated with a halving of fatal and non-fatal myocardial infarction. (Scottish COmputed Tomography of the HEART Trial [SCOT-HEART]; NCT01149590

Leveraging gene expression subgroups to classify DLBCL patients and select for clinical benefit from a novel agent

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease, commonly described by cell-of-origin (COO) molecular subtypes. We sought to identify novel patient subgroups through an unsupervised analysis of a large public dataset of gene expression profiles from newly diagnosed de novo DLBCL patients, yielding 2 biologically distinct subgroups characterized by differences in the tumor microenvironment. Pathway analysis and immune deconvolution algorithms identified higher B-cell content and a strong proliferative signal in subgroup A and enriched T-cell, macrophage, and immune/inflammatory signals in subgroup B, reflecting similar biology to published DLBCL stratification research. A gene expression classifier, featuring 26 gene expression scores, was derived from the public dataset to discriminate subgroup A (classifier-negative, immune-low) and subgroup B (classifier-positive, immune-high) patients. Subsequent application to an independent series of diagnostic biopsies replicated the subgroups, with immune cell composition confirmed via immunohistochemistry. Avadomide, a CRL4CRBN E3 ubiquitin ligase modulator, demonstrated clinical activity in relapsed/refractory DLBCL patients, independent of COO subtypes. Given the immunomodulatory activity of avadomide and the need for a patient-selection strategy, we applied the gene expression classifier to pretreatment biopsies from relapsed/refractory DLBCL patients receiving avadomide (NCT01421524). Classifier-positive patients exhibited an enrichment in response rate and progression-free survival of 44% and 6.2 months vs 19% and 1.6 months for classifier-negative patients (hazard ratio, 0.49; 95% confidence interval, 0.280-0.86; P = .0096). The classifier was not prognostic for rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone or salvage immunochemotherapy. The classifier described here discriminates DLBCL tumors based on tumor and nontumor composition and has potential utility to enrich for clinical response to immunomodulatory agents, including avadomide

A NuSTAR Survey of Nearby Ultraluminous Infrared Galaxies

We present a Nuclear Spectroscopic Telescope Array (NuSTAR), Chandra, and XMM-Newton survey of nine of the nearest ultraluminous infrared galaxies (ULIRGs). The unprecedented sensitivity of NuSTAR at energies above 10 keV enables spectral modeling with far better precision than was previously possible. Six of the nine sources observed were detected sufficiently well by NuSTAR to model in detail their broadband X-ray spectra, and recover the levels of obscuration and intrinsic X-ray luminosities. Only one source (IRAS 13120–5453) has a spectrum consistent with a Compton-thick active galactic nucleus (AGN), but we cannot rule out that a second source (Arp 220) harbors an extremely highly obscured AGN as well. Variability in column density (reduction by a factor of a few compared to older observations) is seen in IRAS 05189–2524 and Mrk 273, altering the classification of these borderline sources from Compton-thick to Compton-thin. The ULIRGs in our sample have surprisingly low observed fluxes in high-energy (>10 keV) X-rays, especially compared to their bolometric luminosities. They have lower ratios of unabsorbed 2–10 keV to bolometric luminosity, and unabsorbed 2–10 keV to mid-IR [O iv] line luminosity than do Seyfert 1 galaxies. We identify IRAS 08572+3915 as another candidate intrinsically X-ray weak source, similar to Mrk 231. We speculate that the X-ray weakness of IRAS 08572+3915 is related to its powerful outflow observed at other wavelengths

Aspects of Two-Photon Physics at Linear e+e- Colliders

We discuss various reactions at future e+e- and gamma-gamma colliders involving real (beamstrahlung or backscattered laser) or quasi--real (bremsstrahlung) photons in the initial state and hadrons in the final state. The production of two central jets with large pT is described in some detail; we give distributions for the rapidity and pT of the jets as well as the di--jet invariant mass, and discuss the relative importance of various initial state configurations and the uncertainties in our predictions. We also present results for `mono--jet' production where one jet goes down a beam pipe, for the production of charm, bottom and top quarks, and for single production of W and Z bosons. Where appropriate, the two--photon processes are compared with annihilation reactions leading to similar final states. We also argue that the behaviour of the total inelastic gamma-gamma cross section at high energies will probably have little impact on the severity of background problems caused by soft and semi--hard (`minijet') two--photon reactions. We find very large differences in cross sections for all two--photon processes between existing designs for future e+e- colliders, due to the different beamstrahlung spectra; in particular, both designs with >1 events per bunch crossing exist.Comment: 51 pages, 13 figures(not included

Total photoproduction cross-section at very high energy

In this paper we apply to photoproduction total cross-section a model we have proposed for purely hadronic processes and which is based on QCD mini-jets and soft gluon re-summation. We compare the predictions of our model with the HERA data as well as with other models. For cosmic rays, our model predicts substantially higher cross-sections at TeV energies than models based on factorization but lower than models based on mini-jets alone, without soft gluons. We discuss the origin of this difference.Comment: 13 pages, 9 figures. Accepted for publication in EPJC. Changes concern added references, clarifications of the Soft Gluon Resummation method used in the paper, and other changes requested by the Journal referee which do not change the results of the original versio

NuSTAR J033202-2746.8: Direct Constraints on the Compton Reflection in a Heavily Obscured Quasar at z ≈ 2

We report Nuclear Spectroscopic Telescope Array (NuSTAR) observations of NuSTAR J033202-2746.8, a heavily obscured, radio-loud quasar detected in the Extended Chandra Deep Field-South, the deepest layer of the NuSTAR extragalactic survey (~400 ks, at its deepest). NuSTAR J033202-2746.8 is reliably detected by NuSTAR only at E > 8 keV and has a very flat spectral slope in the NuSTAR energy band ($\Gamma =0.55^{+0.62}_{-0.64}$; 3-30 keV). Combining the NuSTAR data with extremely deep observations by Chandra and XMM-Newton (4 Ms and 3 Ms, respectively), we constrain the broad-band X-ray spectrum of NuSTAR J033202-2746.8, indicating that this source is a heavily obscured quasar ($N_{\rm H}=5.6^{+0.9}_{-0.8}\times 10^{23}$ cm–2) with luminosity L 10-40 keV ≈ 6.4 × 1044 erg s–1. Although existing optical and near-infrared (near-IR) data, as well as follow-up spectroscopy with the Keck and VLT telescopes, failed to provide a secure redshift identification for NuSTAR J033202-2746.8, we reliably constrain the redshift z = 2.00 ± 0.04 from the X-ray spectral features (primarily from the iron K edge). The NuSTAR spectrum shows a significant reflection component ($R=0.55^{+0.44}_{-0.37}$), which was not constrained by previous analyses of Chandra and XMM-Newton data alone. The measured reflection fraction is higher than the R ~ 0 typically observed in bright radio-loud quasars such as NuSTAR J033202-2746.8, which has L 1.4 GHz ≈ 1027 W Hz–1. Constraining the spectral shape of active galactic nuclei (AGNs), including bright quasars, is very important for understanding the AGN population, and can have a strong impact on the modeling of the X-ray background. Our results show the importance of NuSTAR in investigating the broad-band spectral properties of quasars out to high redshift

The NuSTAR Serendipitous Survey: Hunting for the Most Extreme Obscured AGN at >10 keV

We identify sources with extremely hard X-ray spectra (i.e., with photon indices of ${\rm{\Gamma }}\lesssim 0.6$) in the 13 deg2 NuSTAR serendipitous survey, to search for the most highly obscured active galactic nuclei (AGNs) detected at $\gt 10\,\mathrm{keV}$. Eight extreme NuSTAR sources are identified, and we use the NuSTAR data in combination with lower-energy X-ray observations (from Chandra, Swift XRT, and XMM-Newton) to characterize the broadband (0.5–24 keV) X-ray spectra. We find that all of the extreme sources are highly obscured AGNs, including three robust Compton-thick (CT; ${N}_{{\rm{H}}}\gt 1.5\times {10}^{24}$ cm−2) AGNs at low redshift ($z\lt 0.1$) and a likely CT AGN at higher redshift (z = 0.16). Most of the extreme sources would not have been identified as highly obscured based on the low-energy ($\lt 10$ keV) X-ray coverage alone. The multiwavelength properties (e.g., optical spectra and X-ray–mid-IR luminosity ratios) provide further support for the eight sources being significantly obscured. Correcting for absorption, the intrinsic rest-frame 10–40 keV luminosities of the extreme sources cover a broad range, from $\approx 5\times {10}^{42}$ to 1045 erg s−1. The estimated number counts of CT AGNs in the NuSTAR serendipitous survey are in broad agreement with model expectations based on previous X-ray surveys, except for the lowest redshifts ($z\lt 0.07$), where we measure a high CT fraction of ${f}_{\mathrm{CT}}^{\mathrm{obs}}={30}_{-12}^{+16} \%$. For the small sample of CT AGNs, we find a high fraction of galaxy major mergers (50% ± 33%) compared to control samples of "normal" AGNs