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The feasibility of utilizing commercially available silica aerogel-based flexible composite blankets as passive thermal control element in applications such as extraterrestrial environments is investigated. Differential scanning calorimetry showed that aerogel blanket was thermally stable over - 150 to 126 °C. The outgassing behavior, e.g., total mass loss, collected volatile condensable materials, water vapor regained and recovered mass loss, was within acceptable range recommended for the space applications. ASTM tension and tear tests confirmed the material’s mechanical integrity. The thermo-optical properties remained nearly unaltered in simulated space environmental tests such as relative humidity, thermal cycling and thermo-vacuum tests and confirmed the space worthiness of the aerogel. Aluminized Kapton stitched or anchored to the blanket could be used to control the optical transparency of the aerogel. These outcomes highlight the potential of commercial aerogel composite blankets as passive thermal control element in spacecraft. Structural and chemical characterization of the material was also done using scanning electron microscopy, Fourier transform infrared spectroscopy and x-ray photoelectron spectroscopy. [ABSTRACT FROM AUTHOR]

Vanadium oxide films, deposited on aluminium (Al), titanium (Ti) and tantalum (Ta) metal substrates by pulsed RF magnetron sputtering at a working pressure of 1.5 x10−2 mbar at room temperature are found to display mixed crystalline vanadium oxide phases viz., VO2, V2O3, V2O5. The films have been characterized by field-emission scanning electron microscopy, X-ray diffraction, differential scanning calorimetry (DSC) and X-ray photoelectron spectroscopy, and their thermo-optical and electrical properties have been investigated. Studies of the deposited films by DSC have revealed a reversible-phase transition found in the temperature range of 45–49 °C. [ABSTRACT FROM AUTHOR]

Sunshield membranes made of germanium‐coated black polyimide (GBP) or Kapton are often used on the reflector/transmitter antenna of satellites for thermal control applications. However, the germanium top layer is prone to degrade during ground storage and implementation. Hence, vacuum/inert gas‐sealed packaging is required for storing the membranes, followed by a staggered fabrication schedule as the shelf‐life of the GBP is identified as only ~6 months. In the present study, microstructural, thermo‐optical, and electrical properties along with X‐ray photoelectron spectroscopy (XPS) studies for evaluating oxidation states of the as‐received and degraded GBP films have been investigated thoroughly. The radio frequency (RF) loss behavior of both the films has also been studied for S band (2.5–3.5 GHz), Ku band (10.5–14.5 GHz), and Ka band (30–35 GHz). Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Protective alumina thin films of different thicknesses (35-95 nm) were grown by pulsed RF magnetron sputtering technique at room temperature on germanium (Ge) coated black polyimide or Kapton substrate which is often employed as sunshield membrane on communications satellite antennas. The thin alumina top layer provides shielding of Ge coating from degradation during storage. The alumina thin film was characterized by X-ray diffraction, field emission scanning electron microscopy and X-ray photoelectron spectroscopy (XPS) techniques to investigate microstructural and electronic characteristics. Thermo-optical properties such as IR emittance, solar absorptance, reflectance and transmittance and electrical property e.g. sheet resistance of the deposited alumina films were measured. The RF losses e.g. insertion loss and return loss were measured in both Ku band (10.5-14.5 GHz) and Ka band (27-40 GHz). Finally, to prove anti-degradation behavior of alumina thin film, water droplet spreading experiments were carried out and evaluated its chemical degradation by XPS. [ABSTRACT FROM AUTHOR]

Indium tin oxide films were deposited on flexible fluorinated ethylene propylene substrate by rf magnetron sputtering at room temperature. The effects of different process parameters, such as substrate etching, sputter power density, simultaneous plasma etching and deposition time, were investigated. The functional properties of the film, i.e. transmittance, reflectance, figure of merit, lattice distortion, sheet resistance and its adhesion to the substrate, were studied. The optimised film showed average transmittance of ∼87% (400-900 nm wavelengths) and sheet resistance value of ∼2·54 kࡎ □-1. The crystal structure, composition and surface morphology of the film were investigated using X-ray diffraction, energy dispersive X-ray spectroscopy and scanning electron microscopy. Further, the space worthiness of the film was examined by simulated space environments, e.g. humidity, thermal cycling and thermovacuum tests. [ABSTRACT FROM AUTHOR]

Vanadium oxide-molybdenum oxide (VO-MO) thin (21-475 nm) films were grown on quartz and silicon substrates by pulsed RF magnetron sputtering technique by altering the RF power from 100 to 600 W. Crystalline VO-MO thin films showed the mixed phases of vanadium oxides e.g., V2O5, V2O3 and VO2 along with MoO3. Reversible or smart transition was found to occur just above the room temperature i.e., at ~45-50 °C. The VO-MO films deposited on quartz showed a gradual decrease in transmittance with increase in film thickness. But, the VO-MO films on silicon exhibited reflectance that was significantly lower than that of the substrate. Further, the effect of low temperature (i.e., 100 °C) vacuum (10−5 mbar) annealing on optical properties e.g., solar absorptance, transmittance and reflectance as well as the optical constants e.g., optical band gap, refractive index and extinction coefficient were studied. Sheet resistance, oxidation state and nanomechanical properties e.g., nanohardness and elastic modulus of the VO-MO thin films were also investigated in as-deposited condition as well as after the vacuum annealing treatment. Finally, the combination of the nanoindentation technique and the finite element modeling (FEM) was employed to investigate yield stress and von Mises stress distribution of the VO-MO thin films. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented regarding a case of a 55-year-old male patient with ossified posterior longitudinal ligament (OPLL) of cervical spine.

Abstract: Silica (SiO2) mono-layer and silica–alumina (SiO2–Al2O3) bi-layer thin films were developed on both SS304 and Ti thin foils by pulsed rf magnetron sputtering. The solar absorptance (α s) and IR emittance (ε ir) of the films were measured. Both α s and ε ir of SS304 and Ti were increased after depositing SiO2 and SiO2–Al2O3 bi-layer thin film. The ratio of solar absorptance and IR emittance (i.e. α s/ε ir) can be tailored in a large range e.g. 3.3–0.850 for SS and 3.66–1.085 for Ti which is useful for many spacecraft subsystems to tailor their operating temperatures. Further, the microstructure, surface morphology and topography of the films were investigated by field emission scanning electron microscopy, energy dispersive X-ray spectroscopy and atomic force microscopy. [Copyright &y& Elsevier]

Smooth, uniform and crystalline vanadium oxide thin films were deposited on quartz by spin coating technique with four different rpm i.e., 1000, 2000, 3000 and 4000 and subsequently post annealed at 350, 450 and 550 °C in vacuum. Transmission electron microscopy (TEM), Field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) techniques were utilized for microstructural characterizations and phase analysis, respectively, for vanadium oxide powder and deposited film. Nanorods were observed to be grown after vacuum annealing. X-ray photoelectron spectroscopy (XPS) technique was utilized to study the elemental oxidation state of deposited vanadium oxide films. Thermo-optical and electrical properties such as solar transmittance (τ s ), reflectance (ρ s ), absorptance (α s ), infrared (IR) emittance (ε ir ) and sheet resistance (R s ) of different thin films were evaluated. Based on the optical characteristics the optimized condition of the film processing was identified to be spin coated at 3000 rpm. Subsequently, the nanoindentation technique was utilized to measure hardness and Young's modulus of the optimized film. The measured nanomechanical properties were found to be superior to those reported for sputtered vanadium oxide films. Finally, temperature dependent phase transition characteristics of optimized vanadium oxide films were studied by differential scanning calorimetry (DSC) technique. Reversible and repeatable phase transition was found to occur in the range of 44–48 °C which was significantly lower than the phase transition temperature (i.e., 68 °C) of bulk VO 2 . [ABSTRACT FROM AUTHOR]

Acquiring good adhesion of ITO thin films on polymer substrate is a major concern, especially for space related applications. Delamination of ITO coating on these polymers can seriously damage the spacecraft. This paper presents the development of highly transparent and conducting ITO thin films on as-received and surface treated fluorinated ethylene propylene (FEP) and Kapton ® substrates by reactive direct current magnetron sputtering. Stability of the ITO coating on FEP and Kapton ® substrates was studied in simulated space environments. Environmental tests such as: relative humidity, thermal cycling and thermo vacuum were performed. Thermo-optical properties and sheet resistance of ITO coated FEP and Kapton ® substrates were studied before and after environmental tests. Optimized ITO coating with thickness of ~ 15 nm on FEP and Kapton ® substrates showed sheet resistance in the range of 2–4 kΩ/sq. with high average transmittance and high IR emittance. Adhesion of ITO coating on FEP substrate was improved by Ar plasma etching. X-ray photoelectron spectroscopy and field emission scanning electron microscopic studies of etched FEP substrate showed defluorination and high roughness of the etched surface which helped for better adhesion of ITO coating. We demonstrated that ITO coated plasma etched FEP substrate showed no change in the sheet resistance and thermo-optical properties. Moreover, ITO coated etched FEP substrate showed good environmental stability than ITO coated untreated FEP substrates. [ABSTRACT FROM AUTHOR]

Transparent and conducting ITO/Ag/ITO (IAI) multilayer coatings were deposited on glass and flexible fluorinated ethylene propylene (FEP) substrates by reactive sputtering using metallic In:Sn (90%:10%) and Ag targets at room temperature. Middle Ag layer thickness was optimized to obtain maximum figure of merit ( ϕ ) and the optimum Ag layer thickness was found to be ~13 nm. The optimized IAI multilayer on glass substrate showed transmittance of ~88.6% and sheet resistance of ~7.1 Ω/sq. The transmittance increased to ~91.4% for the IAI multilayer deposited on one side etched glass. The optimized IAI multilayer coating was also deposited on flexible FEP substrates. The electrical, optical, structural and morphological properties of IAI deposited on glass and FEP substrates were compared. IAI deposited on FEP substrate showed transmittance of ~90.2% at λ = 550 nm, sheet resistance of ~6.9 Ω/sq. and figure of merit of ~52 × 10 −3 Ω −1 . Bending test of IAI deposited FEP proved the high flexibility of IAI multilayer for the flexible transparent electrode applications. Solar selectivity study of IAI on FEP substrate showed it can effectively reflect the higher wavelength region of solar spectrum and can be used as a flexible solar spectrum segregator. Optical haze measurements of IAI coated glass and FEP show that high haze value can be achieved by increasing the roughness on non-coated side of the FEP substrate. [ABSTRACT FROM AUTHOR]

ITO thin films were deposited on flexible fluorinated ethylene propylene (FEP) substrates by pulsed direct current reactive magnetron sputtering system using an In:Sn (90%–10% wt.) alloy target. The influence of the deposition parameters (argon and oxygen flow rates, and substrate temperature) and effect of coating thickness on the optical, electrical, structural and microstructural properties of ITO thin films deposited on FEP was investigated. The thickness of the ITO coatings was varied from 5 to 180 nm. The optimized ITO coating (10 nm thick) exhibited high IR emittance (79%) on FEP substrate with high average solar transmittance (94.0%) and moderate sheet resistance (3 kΩ/sq.). We also investigated in detail the angular dependence of reflectance as well as haze factor of thin ITO coatings. Our results suggest that 10 nm thick ITO coating exhibits an average haze factor of 8.6%. The high value of IR emittance, moderate sheet resistance and high solar transmittance along with low haze factor indicate the suitability of ITO thin films on FEP substrates as flexible optical solar reflector for space applications. [ABSTRACT FROM AUTHOR]

COVID-19 was declared as a pandemic by the World Health Organization (WHO) in March 2020. The COVID-19 pandemic became a major public health burden with a high morbidity and mortality rate. In response to the pandemic, several COVID-19 vaccines were introduced to prevent infection and control the transmission of the virus. These vaccines have proven to be effective and relatively safe causing mild side effects in most individuals. However, these vaccines have also been associated with rare but life-threatening complications involving multiple body systems including the pulmonary, cardiovascular, lymphatic, vascular, gastrointestinal, and the central and peripheral nervous systems. This article describes the various severe complications and highlights the role of radiologists and imaging in aiding the prompt recognition of vaccine associated complications allowing for improved patient management., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

A significant increase in the striatal specific activity of DT diaphorase is demonstrable from one to six weeks after intrastriatal injection of kainic acid (KA). At six weeks, there is a significant dose-response relation (ANOVA, F(2,18) = 25.8, p less than 0.001); 1, 3 and 5 nmoles produce 12.3, 39.6 and 118% increases, respectively. Loss of acetylcholinesterase activity (AChE), used as an indicator of neuronal damage, is positively correlated with the enhanced DT diaphorase activity (r = 0.823, p less than 0.01).