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We created high-resolution shape models of Phobos and Deimos using stereophotoclinometry and united images from Viking Orbiter, Phobos 2, Mars Global Surveyor, Mars Express, and Mars Reconnaissance Orbiter into a single coregistered collection. The best-fit ellipsoid to the Phobos model has radii of (12.95 ± 0.04) km × (11.30 ± 0.04) km × (9.16 ± 0.03) km, with an average radius of (11.08 ± 0.04) km. The best-fit ellipsoid to the Deimos model has radii of (8.04 ± 0.08) km × (5.89 ± 0.06) km × (5.11 ± 0.05) km with an average radius of (6.27 ± 0.07) km. The new shape models offer substantial improvements in resolution over existing shape models, while remaining globally consistent with them. The Phobos model resolves grooves, craters, and other surface features ~ 100 m in size across the entire surface. The Deimos model is the first to resolve geological surface features. These models, associated data products, and a searchable, coregistered collection of images across six spacecraft are publicly available in the Small Body Mapping Tool, and will be archived with the NASA Planetary Data System. These products enable an array of future studies to advance the understanding of Phobos and Deimos, facilitate coregistration of other past and future datasets, and set the stage for planning and operating future missions to the moons, including the upcoming Martian Moons eXploration (MMX) mission. [ABSTRACT FROM AUTHOR]

Tissue engineering aims to exploit the regenerative capacity of cells and connect the inherent ability of the body to repair and regenerate. Cells are seeded onto a porous three-dimensional scaffold in tissue engineering, which will provide protection and direct cells to the development of new tissue-like structures. These scaffolds can provide a medium for the delivery, under controlled conditions of growth factors release and drug delivery. Herein, nanocellulose was extracted from Ixora coccinea L. plant root, plasticized scaffold of nanocellulose were prepared by using glycerol, gelatin, and PEG 600 followed by morphological characterized by FTIR, XRD, SEM, and tensile modulus analysis. FTIR indicated extracted nanocellulose is without any hemicelluloses, lignin, and non-cellulosic materials. XRD data displayed the extracted nanocellulose has a crystal size of around 3.6 nm while SEM data revealed the fiber diameter was around 20 µm. In the tensile modulus analysis, 1% PEG 600 exhibited the highest (tensile strength 69 MPa with young's modulus 67.326 MPa) as compared to glycerol and gelatin and hence selected for further studies. The In vitro cytocompatibility studies revealed that nanocellulose and 1% PEG 600 incorporated nanocellulose scaffolds were cell-friendly, promote cell proliferation, and do not show RBC aggregation as well as haemolysis suggesting its potential in various tissue engineering applications. The novelty of this work is that the nanocellulose extracted from the root of I. coccineahas traditional medicinal values in Ayurveda. [ABSTRACT FROM AUTHOR]

The MEGANE instrument onboard the MMX mission will acquire gamma-ray and neutron spectroscopy data of Phobos to determine the elemental composition of the martian moon and provide key constraints on its origin. To produce accurate compositional results, the irregular shape of Phobos and its proximity to Mars must be taken into account during the analysis of MEGANE data. The MEGANE team is adapting the Small Body Mapping Tool (SBMT) to handle gamma-ray and neutron spectroscopy investigations, building on the demonstrated record of success of the SBMT being applied to scientific investigations on other spacecraft missions of irregularly shaped bodies. This is the first application of the SBMT to a gamma-ray and neutron spectroscopy dataset, and the native, three-dimensional foundation of the SBMT is well suited to MEGANE's needs. In addition, the SBMT will enable comparisons between the MEGANE datasets and other datasets of the martian moons, including data from previous spacecraft missions and MMX's multi-instrument suite. [ABSTRACT FROM AUTHOR]

Precipitation chemistry measurements are essential to estimate the deposition of ionic components that are beneficial or harmful to the ecosystems and quantify the wet scavenging of the atmospheric constituents. A long-term (2006 to 2016) database of the water-soluble inorganic components in the rainwater (RW) at Pune (an urban location) and Sinhagad (a high-altitude rural location) in southwest India was examined to understand the trends in measured anthropogenic components and the factors controlling the chemistry of RW in this region. We observed the long-term increasing trends in NH4+ at Pune and SO42−, NO3¯, and NH4+ at Sinhagad. About 10% of rain samples were acidic (below 5.6). Low pH values were generally measured at Pune (8%) and Sinhagad (9%) stations when the air mass back trajectories (AMBTs) originated from land. This study suggests that NO3¯ plays a vital role in acidifying the rain in both the sampling stations, though SO42− remains the dominant factor. The high concentrations of Ca2+ and NH4+ have played a significant role in neutralizing the acidity of RW. The cluster analysis of AMBTs showed that at Pune 74% and Sinahagd 65% of rain events were associated with oceanic air masses from the Arabian Sea. [ABSTRACT FROM AUTHOR]

The properties of the atmospheric aerosols depend on the source region and on the modifications that occur during their transport in the air. We have studied physical and chemical properties of aerosols along with their sink mechanism over two locations in southwest India, an urban site (Pune) and well-established climate observatory at Sinhagad (SINH), which represents rural and high altitude site. The ground-based measurements of aerosols, together with their radiative properties in this study have provided means to understand the observed variability and the impact on the aerosol radiative properties effectively over this region. The annual mean elemental carbon concentration (3.4 µg m− 3) at Pune was observed about three times higher compared to SINH (1.3 µg m− 3), indicating strong emissions of carbon-rich aerosols at the urban location. Aerosol optical properties were derived using the OPAC model which were used to compute the Aerosol radiative forcing (ARF) over both stations calculated using SBDART (Santa Barbara DISORT Atmospheric Radiative Transfer) model shows pronounced seasonal variations due to changes in aerosol optical depth and single scattering albedo at both locations. The year-round ARF was 4–5 times higher over Pune (31.4 ± 3.5 Wm− 2) compared to SINH (7.2 ± 1.1 Wm− 2). The atmospheric heating rate due to aerosols shows a similar pattern as ARF for these locations. The heating was higher in the wintertime, ~ 0.9–1.6 K day− 1 at Pune, and ~ 0.3–0.6 K day− 1 at SINH. The estimated scavenging ratio was found high for NO3− and Ca.2+. The wet deposition fluxes of Cl−, SO42−, Na+, Mg2+ were observed higher for SINH as compared to Pune, due to the high amount of rain received at SINH. [ABSTRACT FROM AUTHOR]

We present an overview of the operations, calibration, geodetic control, photometric standardization, and processing of images from the Mercury Dual Imaging System (MDIS) acquired during the orbital phase of the MESSENGER spacecraft's mission at Mercury (18 March 2011–30 April 2015). We also provide a summary of all of the MDIS products that are available in NASA's Planetary Data System (PDS). Updates to the radiometric calibration included slight modification of the frame-transfer smear correction, updates to the flat fields of some wide-angle camera (WAC) filters, a new model for the temperature dependence of narrow-angle camera (NAC) and WAC sensitivity, and an empirical correction for temporal changes in WAC responsivity. Further, efforts to characterize scattered light in the WAC system are described, along with a mosaic-dependent correction for scattered light that was derived for two regional mosaics. Updates to the geometric calibration focused on the focal lengths and distortions of the NAC and all WAC filters, NAC–WAC alignment, and calibration of the MDIS pivot angle and base. Additionally, two control networks were derived so that the majority of MDIS images can be co-registered with sub-pixel accuracy; the larger of the two control networks was also used to create a global digital elevation model. Finally, we describe the image processing and photometric standardization parameters used in the creation of the MDIS advanced products in the PDS, which include seven large-scale mosaics, numerous targeted local mosaics, and a set of digital elevation models ranging in scale from local to global. [ABSTRACT FROM AUTHOR]

We investigate the impact of ErAs:GaAs and LuAs:GaAs superlattice structures with different LuAs/ErAs nanoparticle depositions and superlattice geometries on terahertz radiation properties of plasmonic photomixers operating at a 780-nm optical wavelength. Our analysis indicates the crucial impact of carrier drift velocity and carrier lifetime on the performance of plasmonic photomixers. While higher carrier drift velocities enable higher optical-to-terahertz conversion efficiencies by offering higher quantum efficiencies, shorter carrier lifetimes allow achieving higher optical-to-terahertz conversion efficiencies by mitigating the negative impact of destructive terahertz radiation from slow photocarriers and preventing the carrier screening effect. [ABSTRACT FROM AUTHOR]