Improved Residual Dense Network for Large Scale Super-Resolution via Generative Adversarial Network

Recent single image super resolution (SISR) studies were conducted extensively on small upscaling factors such as x2 and x4 on remote sensing images, while less work was conducted on large factors such as the factor x8 and x16. Owing to the high performance of the generative adversarial networks (GANs), in this paper, two GAN’s frameworks are implemented to study the SISR on the residual remote sensing image with large magnification under x8 scale factor, which is still lacking acceptable results. This work proposes a modified version of the residual dense network (RDN) and then it been implemented within GAN framework which named RDGAN. The second GAN framework has been built based on the densely sampled super resolution network (DSSR) and we named DSGAN. The used loss function for the training employs the adversarial, mean squared error (MSE) and the perceptual loss derived from the VGG19 model. We optimize the training by using Adam for number of epochs then switching to the SGD optimizer. We validate the frameworks on the proposed dataset of this work and other three remote sensing datasets: the UC Merced, WHU-RS19 and RSSCN7. To validate the frameworks, we use the following image quality assessment metrics: the PSNR and the SSIM on the RGB and the Y channel and the MSE. The RDGAN evaluation values on the proposed dataset were 26.02, 0.704, and 257.70 for PSNR, SSIM and the MSE, respectively, and the DSGAN evaluation on the same dataset yielded 26.13, 0.708 and 251.89 for the PSNR, the SSIM, and the MSE

Hidden impurities in transparent conducting oxides: study of vacancies-related defects and impurities in (Cu–Ni) co-doped ZnO films

The effect of hydrogen and nitrogen impurities on the physical properties of transparent conductive oxides is investigated in this study. Therefore, 5 wt.% of copper and 5 wt.% of nickel co-doped zinc oxide ((Cu–Ni)/ZnO) films were prepared using the sol–gel method. The (Cu–Ni)/ZnO films were annealed in an oven at 500 °C for 2 h under air, vacuum, nitrogen, and argon atmospheres. The synthesized zinc hydroxide film was transformed to zinc oxide film during the annealing by evaporating H 2O. Films annealed under the mentioned atmosphere including as-prepared one were characterized by analyzing with UV–Vis and FTIR spectra in addition to the 2D mapping electrical conductivity of the surface measured by the 4-point probe. The annealed films under air, vacuum, and argon atmospheres led to generate H-related impurities bounded to the oxygen vacancy (H O) which they act as shallow donor defects resulting in forming (Cu–Ni)/ZnO films into n-type materials. Whereas, the film annealed under a nitrogen atmosphere has N-related defects bounding to the zinc vacancy (N Zn) which they act as shallow acceptor defects resulting in transforming the film from n-type to p-type. These defects affect the optical, electrical, and optoelectronic properties of the (Cu–Ni)/ZnO films

Synthesis and Characterization of Erbia Doped Metal Oxide Nanofibers for Applications in the Rmophotovoltaics

Titania (TiO2) nanofibers doped with erbia (Er2O3) have been synthesized by electrospinning mixtures of polymers, titanium-containing materials, and erbia particles. These electrospun nanofibers are subsequently annealed at temperatures of 800, 900, 1000, and 1050 degrees C to remove the organics and leave behind the metal oxides. The crystal structure and optical properties of the metal oxides depend on the annealing temperature, and we characterize these nanofibers using x-ray diffraction and Fourier transform infrared spectroscopy (FTIR). An Er2Ti2O7 phase is formed in an amount which depends on the annealing temperature, and relationships between the nature of FTIR spectra and the relative amounts of different phases are demonstrated. Finally, the relevance of this work to thermophotovoltaics and other applications is discussed. (c) 2007 American Vacuum Society

Measurement and ab initio Investigation of Structural, Electronic, Optical, and Mechanical Properties of Sputtered Aluminum Nitride Thin Films

We report our results on highly textured aluminum nitride (AlN) thin films deposited on glass substrates, oriented along the c-axis, using DC-magnetron sputtering technique for different values of back pressure. The structural, electronic, optical, piezoelectric, dielectric, and elastic properties of sputtered AlN thin films are measured and characterized. In particular, X-ray powder diffraction (XRD) technique shows that AlN thin films exhibit a hexagonal structure. Moreover, we employed ab initio simulations of AlN using the Vienna Ab Initio Simulation Package (VASP) to investigate the structural and the electronic properties of hexagonal AlN structures. The experimental lattice parameters of the as-prepared thin films agree well with those calculated using the total energy minimization approach. The optical parameters of AlN thin films, such as transmittance and refractive index, were measured using UV–vis measurements. Our measurements of refractive index, n, of AlN thin films yield a value of 2.2. Furthermore, the elastic, piezoelectric, and dielectric tensors of AlN crystal are calculated using VASP. The dynamical Born effective charge tensor is reported for all atoms in the unit cell of AlN. Interestingly, ab initio simulations indicate that AlN has a static dielectric constant approximately equal to 4.68, which is in good agreement with the reported experimental value. In addition, the clamped-ion piezoelectric tensor is calculated. The diagonal components of the piezoelectric tensor are found to be e33=1.79 C/m2 and e31=−0.80 C/m2. The large values of the piezoelectric coefficients show that a polar AlN crystal exhibits a strong microwave piezoelectric effect. Additionally, the components of the elastic moduli tensor are calculated. The extraordinary electronic, optical, piezoelectric, and elastic properties make AlN thin films potential candidates for several optoelectronic, elastic, dielectric, and piezoelectric applications

Experimental study of the Al-Mg-Sr phase diagram at 400°C

TheAl-Mg-Sr systemis experimentally studied at 400∘C using EPMA and XRD techniques. It was determined that the intermetallic phases in the Al-Mg-Sr system have a tendency to form extended substitutional solid solutions. Two ternary phases were found in this system. Solubility limits of binary and ternary phases were determined and the phase equilibria among phases were established. The isothermal section of the Al-Mg-Sr system at 400∘C has been constructed using results of the phase analysis and experimental literature data

Association Of BCR-ABL Alternative Splice Variants with Disease Progression, Treatment Response and Survival in Chronic Myeloid Leukemia Patients Treated with Firstline imatinib Monotherapy

Background: Alternative RNA splicing has diverse biological effects in heath as well as disease. It also contributes to cancer onset and progression. Chronic Myeloid Leukemia (CML) results due to BCR-ABL fusion oncogene that is created due to chromosomal translocation t [9; 22] [q34; q11]). BCR-ABL is target of tyrosine kinase inhibitors (TKIs). BCR-ABL through alternative splicing can generate b2a2, b3a2 and some other rare splicing variants. BCR-ABL variants may vary in their response to TKI treatment and disease progression potential, which is a major factor contributing to dismal treatment outcome in CML. Objective: The objective of this study is to investigate correlation of BCR-ABL splice variants with TKI treatment outcome and survival in three phases of CML that has rarely been studied previously.Methods: BCR-ABL splice variants were studied using reverse transcriptase PCR (RT-PCR). in 70 CML patients from three phases of CML who were receiving imatinib (TKI) treatment.Results: Frequencies of different BCR/ABL splice variants like b3a2, b2a2 and b3a2+b2a2 were 49 (70%), 15 (21.4%) and 6 (8.6%), respectively. Splice variant b2a2 were more common (53.3%) in chronic phase CML (CP-CML) while b3a2 had higher frequency in advanced phases of CML (44.9%). CML patients with b2a2 transcript had better complete cytogenetic response and major molecular response to TKI treatment overall (100% vs. 24.5%) as well as in CP-CML (100% vs. 85.7%) and superior survival when compared to patients with b3a2 splice variant. All patients who died had male gender, less than 33 years age, b3a2 transcript, advanced phases of CML and imatinib resistance.Conclusions: Splice variant b3a2 was associated with CML progression, poorer survival and inferior treatment outcome as compared to b2a2. Further investigations on BCR-ABL splice variants and their roles in CML pathogenesis can provide deeper insights into CML biology and new targets for BCR-ABL positive leukemia treatment.          Keywords: CML; BCR-ABL splice variants; Progression; Survival; Treatment outcome 

Documenting the Recovery of Vascular Services in European Centres Following the Initial COVID-19 Pandemic Peak: Results from a Multicentre Collaborative Study

Objective: To document the recovery of vascular services in Europe following the first COVID-19 pandemic peak. Methods: An online structured vascular service survey with repeated data entry between 23 March and 9 August 2020 was carried out. Unit level data were collected using repeated questionnaires addressing modifications to vascular services during the first peak (March – May 2020, “period 1”), and then again between May and June (“period 2”) and June and July 2020 (“period 3”). The duration of each period was similar. From 2 June, as reductions in cases began to be reported, centres were first asked if they were in a region still affected by rising cases, or if they had passed the peak of the first wave. These centres were asked additional questions about adaptations made to their standard pathways to permit elective surgery to resume. Results: The impact of the pandemic continued to be felt well after countries’ first peak was thought to have passed in 2020. Aneurysm screening had not returned to normal in 21.7% of centres. Carotid surgery was still offered on a case by case basis in 33.8% of centres, and only 52.9% of centres had returned to their normal aneurysm threshold for surgery. Half of centres (49.4%) believed their management of lower limb ischaemia continued to be negatively affected by the pandemic. Reduced operating theatre capacity continued in 45.5% of centres. Twenty per cent of responding centres documented a backlog of at least 20 aortic repairs. At least one negative swab and 14 days of isolation were the most common strategies used for permitting safe elective surgery to recommence. Conclusion: Centres reported a broad return of services approaching pre-pandemic “normal” by July 2020. Many introduced protocols to manage peri-operative COVID-19 risk. Backlogs in cases were reported for all major vascular surgeries

On the precipitates and mechanical properties of magnesium–yttrium sheets

Light-weight wrought magnesium alloys is an important part of the weight reduction in automobiles industry for improve their fuel efficiency. Yttrium containing magnesium alloy is a potential material in this perspective. In this work, two magnesium–yttrium alloys (C and D alloys) were cast and rolled to 2 mm thick sheets. The mechanical properties of these hot rolled and annealed sheets were determined. Optical microscope and scanning electron microscope equipped with EDX were used to investigate microstructure evolution during thermo-mechanical processing in the studied alloys. Precipitates evolution during hot rolling and annealing processes were analyzed and compared with those calculated using thermo-chemical software (FactSage). Schiel phase distribution diagrams of C and D alloys were calculated using FactSage

A Context-Aware Android Malware Detection Approach Using Machine Learning

The Android platform has become the most popular smartphone operating system, which makes it a target for malicious mobile apps. This paper proposes a machine learning-based approach for Android malware detection based on application features. Unlike many prior research that focused exclusively on API Calls and permissions features to improve detection efficiency and accuracy, this paper incorporates applications’ contextual features with API Calls and permissions features. Moreover, the proposed approach extracted a new dataset of static API Calls and permission features using a large dataset of malicious and benign Android APK samples. Furthermore, the proposed approach used the Information Gain algorithm to reduce the API and permission feature space from 527 to the most relevant 50 features only. Several combinations of API Calls, permissions, and contextual features were used. These combinations were fed into different machine-learning algorithms to show the significance of using the selected contextual features in detecting Android malware. The experiments show that the proposed model achieved a very high accuracy of about 99.4% when using contextual features in comparison to 97.2% without using contextual features. Moreover, the paper shows that the proposed approach outperformed the state-of-the-art models considered in this work