Coronary stent healing in cancer patients: an optical coherence tomography perspective

Objective: This study assessed stent healing patterns and cardiovascular outcomes by optical coherence tomography (OCT) in cancer patients after drug-eluting stent (DES) placement.Background: Cancer treatment, owing to its cytotoxic and antiproliferative effects, could delay stent healing and increase stent thrombosis risk, especially when dual antiplatelet therapy (DAPT) is discontinued early for oncological treatment. OCT can assess stent endothelialization and other healing parameters, which may provide clinical guidance in these challenging scenarios.Methods: This single-center retrospective study enrolled all cancer patients who underwent OCT for assessment of vascular healing patterns after prior DES placement from November 2009 to November 2018. Primary study endpoints were stent healing parameters, including stent coverage, apposition, degree of expansion, neointimal hyperplasia heterogeneity, in-stent restenosis, stent thrombosis, and overall survival (OS).Results: A total of 67 patients were included in this study. Mean time between DES placement and OCT evaluation was 154 +/- 82 days. Stent healing matched published values for DES in non-cancer patients (P >= 0.063). At 1 year, the OS was 86% (95% confidence interval [CI]: 78-96%) with 0% incidence of acute coronary syndrome. Advanced cancers and active chemotherapies were associated with inferior OS (P = 0.024, hazard ratio [HR]: 3.50, 95% CI: 1.18-10.42 and P = 0.026, HR: 2.65, 95% CI: 1.13-6.22, respectively), while stent healing parameters were unassociated with OS. Forty-one patients (61%) had DAPT duration <= 6 months.Conclusions: Stent healing of contemporary DES appears similar in cancer and non-cancer patients. Cardiovascular risk of cancer patients after DES placement can be managed to facilitate timely cancer therapies, as the underlying malignancy and active chemotherapy ultimately determine survival.Cardiovascular Aspects of Radiolog

Structural and optical properties of ZnO and Al-doped ZnO microrods obtained by spray pyrolysis method using different solvents

ZnO and Al-doped ZnO microrods were obtained by spray pyrolysis method using different solvents such as methanol and propanol. The effect of the type of solvent in the starting solution on the structural, morphological and optical properties of the samples was investigated. X-ray diffraction patterns showed that the undoped and Al-doped ZnO microrods exhibited hexagonal crystal structure with a preferred orientation along (0 0 2) direction. Surface morphology of the samples obtained by scanning electron microscopy revealed that undoped and Al-doped ZnO microrods grew as quasi-aligned hexagonal shaped microrods with diameters varying between 0.7 and 1.3 ?m irrespective of solvents used. Optical studies indicated that microrods had a low transmittance (?30%) and the band gap increased from 3.24 to 3.26 eV upon Al doping. Photoluminescence measurements indicated the existence of two emission bands in the spectra: one sharp ultraviolet luminescence at ?383 nm and one broad visible emission ranging from 420 to 580 nm. © 2012 Elsevier Ltd. All rights reserved

The influence of substrate temperature on electrical properties of Cu/CdS/SnO2 Schottky diode

Polycrystalline CdS samples on the SnO2 coated glass substrate were obtained by vacuum evaporation method at low substrate temperatures (T S=200 and 300 K) instead of the commonly used vacuum evaporation at high substrate temperatures (TS>300 K). X-ray diffraction studies showed that the textures of the films are hexagonal with a strong (0 0 2) preferred direction. Circular Cu contacts were deposited on the upper surface of the CdS thin films at 200 K by vacuum evaporation. The effects of low substrate temperature on the currentvoltage (IV) characteristics of the Cu/CdS/SnO 2 structure were investigated in the temperature range 100300 K. The Cu/CdS (at 300 K)/SnO2 structure shows exponential currentvoltage variations. However, IV characteristics of the Cu/CdS (at 200 K)/SnO2 structure deviate from exponential behavior due to high series resistance. The diodes show non-ideal IV behavior with an ideality factor greater than unity. The results indicate that the current transport mechanism in the Cu/CdS (at 300 K)/SnO2 structure in the whole temperature range is performed by tunneling with E00=143 meV. However, the current transport mechanism in the Cu/CdS (at 200 K)/SnO2 structure is tunneling in the range 200300 K with E00=82 meV. © 2011 Elsevier B.V

Growth of Cu2ZnSnS4 (CZTS) thin films using short sulfurization periods

Olgar, Mehmet Ali/0000-0002-6359-8316;WOS: 000457544900001In this study CZTS thin films were grown by a two-stage process that involved sequential sputter deposition of metallic Cu, Zn, and Sn layers on Mo coated glass substrates followed by RTP annealing at 530 and 560 degrees C for various dwell times (1, 60, and 180 s). CZTS thin films obtained by reaction at different sulfurization temperatures and reaction times were characterized employing XRD, Raman spectroscopy, SEM, EDX, and photoluminescence. It was observed that it is possible to obtain Cu-poor and Zn-rich CZTS thin films with short dwell time of reactions. XRD pattern and Raman spectra of the films showed formation of kesterite CZTS structure and some secondary phases such as CuS, SnS, SnS2 . the full-width-at-half-maximum (FWHM) values extracted from the (112) diffraction peaks of the CZTS thin films showed that extension of the sulfurization time provides better crystalline quality except for the CZTS560-60 thin film. SEM surface microstructure of the films displayed non-uniform, dense, and polycrystalline structure. the optical band gap of the films as determined by photoluminescence was found to be about 1.36-1.38 eV

Preparation and characterization of new window material CdS thin films at low substrate temperature (<300 K) with vacuum deposition

Low-temperature vacuum deposition instead of the commonly used vacuum deposition at high substrate temperatures has been applied to prepare new window material CdS thin films. The structural, optical and electrical properties of vacuum-evaporated CdS thin films were investigated as a function of substrate temperature (100300 K) and the post-deposition annealing temperature (at 473, 573 and 673 K). It was determined that films deposited at all substrate temperatures were polycrystalline in nature with hexagonal structure and a strong (0 0 2) texture. The AFM and SEM studies showed that the microstructures of the as-deposited films agreed with the expectations from structure zone model. X-ray diffraction studies showed that the crystallinity of the CdS films was improved on annealing. Optical spectroscopy results of the films indicated that the optical band gap value increased from 2.40 to 2.42 eV with decreased substrate temperature. Increasing the annealing temperature sharpened the band edge. The dark resistivity increased from 4.5×103 to 7.3×103 ? cm and the carrier concentration decreased from 4.7×1017 to 3.5×1015 cm-3 as the substrate temperature decreased from 300 to 100 K. © 2011 Elsevier Ltd. All rights reserved.Karadeniz Teknik Üniversitesi: 2007.111.001.1This work was supported by the Research Fund of Karadeniz Technical University, Trabzon , under Contract no. 2007.111.001.1. Authors would like to thank Dr. Mustafa Akdoğan of Abant İzzet Baysal University performing the AFM measurements

Current transport mechanism in CdS thin films prepared by vacuum evaporation method at substrate temperatures below room temperature

CdS thin films were deposited by vacuum deposition method at low substrate temperatures instead of the commonly used vacuum deposition at high substrate temperatures (T S > 300 K). The effect of low substrate temperature on the current transport mechanisms in polycrystalline CdS thin films has been studied as a function of temperature over the temperature range 100-300 K. Both thermally assisted tunneling of carriers through and thermionic emission over the grain boundary potential have contributions to the conduction in the range 250-300 K for the sample prepared at 300 K substrate temperature. The dominant conduction mechanism of the samples prepared at 200 K and 100 K is determined as thermionic emission over 200 K and Mott's hopping process below 200 K. The Mott's hopping process is not applicable for the sample prepared at 300 K. © 2011 Elsevier B.V. All rights reserved

Growth of Cu 2 ZnSnS 4 (CZTS) thin films using short sulfurization periods

In this study CZTS thin films were grown by a two-stage process that involved sequential sputter deposition of metallic Cu, Zn, and Sn layers on Mo coated glass substrates followed by RTP annealing at 530 and 560 °C for various dwell times (1, 60, and 180 s). CZTS thin films obtained by reaction at different sulfurization temperatures and reaction times were characterized employing XRD, Raman spectroscopy, SEM, EDX, and photoluminescence. It was observed that it is possible to obtain Cu-poor and Zn-rich CZTS thin films with short dwell time of reactions. XRD pattern and Raman spectra of the films showed formation of kesterite CZTS structure and some secondary phases such as CuS, SnS, SnS 2 . The full-width-at-half-maximum (FWHM) values extracted from the (112) diffraction peaks of the CZTS thin films showed that extension of the sulfurization time provides better crystalline quality except for the CZTS560-60 thin film. SEM surface microstructure of the films displayed non-uniform, dense, and polycrystalline structure. The optical band gap of the films as determined by photoluminescence was found to be about 1.36-1.38 eV. © 2019 IOP Publishing Ltd

Structural, optical and magnetic properties of Cd1-xCo xS thin films prepared by spray pyrolysis

Structural, optical and magnetic properties of CdS thin films with the addition of Co prepared by (i) spray pyrolysis of Cd1-xCo xS (x?0.10) thin films (Type 1) and (ii) Co diffusion doped CdS films (Type 2) were investigated. The undoped film has a hexagonal structure with a strong (112) preferred orientation. As the Co concentration in CdS is increased, the preferred orientation changes from (112) to (002) direction. X-ray photoelectron spectroscopy (XPS) analysis shows that Co atoms on the surface of films are found to be bounded either to S atoms or O atoms. Although most of the bindings of Co atoms include Co-O bondings, some of them replace the Cd atoms by making chemical bounds with S atoms. The transmittance spectra indicate the four characteristic absorption maxima at the wavelengths of 680, 685, 729 and 744 nm, which were not observed for the undoped CdS film. Band gap energy Eg decreases from 2.43 to 2.37 eV with increasing Co content from x = 0 to 0.10. The Co-doped Cd1-xCoxS films grown by spray pyrolysis (Type 1) didnot show any sign of ferromagnetic behavior. However, the Co diffused CdS films (Type 2) have clear ferromagnetic loops. © 2008 Elsevier B.V. All rights reserved

A research on growth and characterization of CdS:Eu thin films

POLAT, ISMAIL/0000-0002-5134-0246WOS: 000454877700007Chemical spray pyrolysis-grown CdS thin films including various quantities of Eu atoms (from 0 to 10at.%) were synthesized on glass slides. the detailed physical properties of the produced CdS and CdS:Eu thin films were explored. Structural analysis showed that Eu-doping enhanced the crystal quality of CdS thin films until 10at.% Eu-doping and further Eu-doping treatment led to a distortion in the CdS structure. in addition, the crystallite sizes of CdS thin films dropped from 36.2 to 32.4nm as Eu-doping level increased to 10at.%. Morphological data showed that increasing Eu-doping remarkably varied the surface morphology of CdS thin films forming smaller grains. Chemical content examinations approved the presence of Eu atoms in CdS structure. From the optical measurements, it was obtained that more transparent CdS thin films with a maximum transmittance of 68% at 820nm were created after 10at.% Eu-doping and bandgap values of samples reduced from 2.58 to 2.47eV with rising of Eu-doping from 0 to 10at.%. Room temperature photoluminescence data demonstrated the formation of two essential peaks for all the samples, which are in turn related to green and yellow bands. Electrical investigation pointed out that Eu-doping enhanced the carrier density of CdS thin films from 4.38 x 10(13) cm(-3) to 2.46 x 10(14) cm(-3) and dropped the resistivity of CdS samples from 2.59 x 10(4) cm to 5.85 x 10(3) cm until 6at.% and further increment of Eu-doping paved the way to get worse electrical data. Thus, it can be brought a conclusion that Eu-doping not only improved the optical properties of CdS thin films, but also restored the electrical properties, which are able to use in the opto-electronic devices.Adana Science and Technology University [17103029]The work has been financially supported by the research fund of Adana Science and Technology University by a Project Number of 17103029

Comparative studies of CdS, CdS:Al, CdS:Na and CdS:(Al-Na) thin films prepared by spray pyrolysis

Yilmaz, Salih/0000-0002-3006-4473WOS: 000367276600036In the present study, the spray pyrolysis technique was used to prepare pure CdS, 4 at.% Al-doped CdS, 4 at.% Na-doped CdS and (4 at.% Al, 4 at.% Na)-co-doped CdS thin films. It was found from X-ray diffraction data that all the specimens showed hexagonal wurtzite structure with the preferred orientation of (101). Scanning electron microscopy results indicated that 4 at.% Al-doping caused a grain growth in the morphology of CdS thin films whereas the 4 at.% Na-doping and (4 at.% Al, 4 at.% Na)-co-doping led to porous structure with small grains. the band gap value of CdS thin films increased to 2.42 eV after 4 at.% Al-doping. However, it reduced to 2.30 eV and 2.08 eV for 4 at.% Na-doping and (4 at.% Al, 4 at.% Na)-co-doping, respectively. the room temperature photoluminescence measurements illustrated that the peak intensity of CdS thin films enhanced with 4 at.% Al-doping while 4 at.% Na-doping and (4 at.% Al, 4 at.% Na)-co-doping caused a decline in the intensity. the maximum carrier concentration and minimum resistivity were obtained for 4 at.% Al-doped CdS thin films, which is associated with the grain growth. Furthermore, (4 at.% Al, 4 at.% Na)-co-doping gave rise to a slight reduction in the carrier concentration and a slight increment in the resistivity. As a result, it can be said that 4 at.% Al-doped CdS thin films exhibited the best electrical and optical properties, which is important for the optoelectronic applications. (C) 2015 Elsevier Ltd. All rights reserved