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The present-day water cycle on Mars has implications for habitability and future human exploration. Water ice clouds and water vapour have been detected above the Tharsis volcanic province, suggesting the active exchange of water between regolith and atmosphere. Here we report observational evidence for extensive transient morning frost deposits on the calderas of the Tharsis volcanoes (Olympus, Arsia and Ascraeus Montes, and Ceraunius Tholus) using high-resolution colour images from the Colour and Stereo Surface Imaging System on board the European Space Agency’s Trace Gas Orbiter. The transient bluish deposits appear on the caldera floor and rim in the morning during the colder Martian seasons but are not present by afternoon. The presence of water frost is supported by spectral observations, as well as independent imagery from the European Space Agency’s Mars Express orbiter. Climate model simulations further suggest that early-morning surface temperatures at the high altitudes of the volcano calderas are sufficiently low to support the daily condensation of water—but not CO2—frost. Given the unlikely seasonal nature of volcanic outgassing, we suggest the observed frost is atmospheric in origin, implying the role of microclimate in local frost formation and a contribution to the broader Mars water cycle.

Byline: S. Karande, N. Deshmukh, V. Rangarajan, A. Agrawal, R. SholapurwalaBackground and Objectives: Brain single-photon emission computed tomography (SPECT) assesses brain function through measurement of regional cerebral blood flow. This [...]

Cancer is a fatal disease and one of the leading causes of death worldwide. The cure rate in cancer treatment remains low; hence, cancer treatment is gradually shifting toward personalized treatment. Artificial intelligence (AI) and radiomics have been recognized as one of the potential areas of research in personalized medicine in oncology. Several researchers have identified the capabilities of AI and radiomics to characterize phenotype and there by predict the outcome of treatment in oncology. Although AI and radiomics have shown promising initial results in diagnosis and treatment in oncology, these technologies are also facing challenges of standardization and scalability. In the last few years, researchers have been trying to develop a research infrastructure for federated machine learning that increases the usability of Big Data for clinical research. These research infrastructures are based on the findable, accessible, interoperable, and reusable (i.e., FAIR) data principles. The India-Dutch “big imaging data approach for oncology in a Netherlands India collaboration” (BIONIC) is a jointly funded initiative by the Dutch Research Council (NWO) and the Indian Ministry of Electronics and Information Technology (MeitY), aiming to introduce radiomic-based research into clinical environments using federated machine learning on geographically dispersed collections of FAIR data. This article described a prototype end-to-end research infrastructure implemented through the BIONIC partnership into a leading cancer care public hospital in India.

Byline: V. Rangarajan, Sumeet. Dua, Nilendu. Purandare, C. Pramesh, George. Karimundackal, Santosh. Menon, Sneha. Shah Sir, Pulmonary inflammatory myofibroblastic tumor (IMT) is a well recognized mimic of lung cancer and [...]

Byline: Sumeet. Dua, Nilendu. Purandare, Siddhartha. Laskar, Sneha. Shah, Kedar. Deodhar, V. Rangarajan Only a minority of the patients who develop recurrence after definitive treatment for cervical cancer are detected [...]

Byline: S. Dua, N. Purandare, S. Shah, V. Rangarajan A 56-year-old man underwent a positron emission tomography/computed tomography (PET/CT) study to investigate his fever of unknown origin. Laboratory parameters were [...]

Byline: N. Purandare, V. Rangarajan Diagnostic imaging plays a pivotal role in cancer management. Imaging has made rapid strides in the past few years with new modalities and new indications [...]

An earth air heat exchanger (EAHE) is an underground heat exchanger that captures or dissipates heat to the ground and hence moderates the temperature of the air flowing through it. Though a promising energy efficient option for thermal comfort, EAHE has not diffused much in the society. One reason for its limited application is space constraint. This includes restrictions on the length and route of the EAHE pipe, positioning of the EAHE, the forced interaction between the civil foundations and the EAHE etc. In order to investigate the effectiveness of such a ‘constrained’ EAHE, an EAHE was installed under such urban constraints and its performance was measured. Simultaneously a predictive 3-dimensional numerical transient model was developed to study the impact of model parameters on the EAHE’s performance. The model was coded on the MATLABⒸplatform. The developed mathematical model is robust, and it was validated at sites with and without urban constraints across three climatic zones. Model predictions were in good agreement with the measured values. The data and model predictions confirmed that in a semi-arid climatic zone if a constrained EAHE is placed strategically, its performance is not compromised, and it provides the desired cooling even when it is installed at a shallower depth.

Renal function is important when assessing the response of a dilated renal pelvis to a diuretic stimulus. Yet there is little in the literature to suggest how this should be undertaken. Our aim was to develop a model which we have called pelvic excretion efficiency (PEE). The PEE, which may be used to assess drainage, is a mathematical model of the ratio of the total kidney excretion to the total amount of isotope extracted from the blood by the kidney. Thirty-three children with a prenatal diagnosis of unilateral renal pelvic dilatation (PUJ) were treated conservatively after birth. As a group, they underwent a total of 164 diuretic DTPA renograms up to the age of 72 months. Drainage was assessed as the response to fruse-mide (defined as the time for the corrected renal curve to fall to 75 of the maximum value in the frusemide part of the study; T75), response to bladder emptying, a change of posture after frusemide (PM), and PEE. The contralateral normal kidney showed a combination of both ‘good’ T75and PM drainage in 51 of renograms while the PEE showed drainage in all. The affected kidney with renal pelvic dilatation showed a combination of both ‘poor’ T75and PM drainage in 42 of renograms. The PEE was low in 99 of these ‘poor drainage’ renograms. The PEE, the ratio of the mathematical model of renal uptake to excretion, is readily calculated and may be a more accurate and specific technique to assess drainage on diuretic renography.

Abstract: The hot dipped galvanized coatings of flexible tubes with variable corrosion resistances were examined by x-ray diffraction and scanning electron microscopy (SEM). Accelerated corrosion was related to wide cracks formed during roll forming of coatings with coarse spangle sizes and preferred orientation of Zn basal planes parallel to the coating surface. Coarse spangled coatings with reduced preferred orientation of basal planes parallel to sheet surfaces formed only thin cracks and accommodated forming strain primarily by plastic flow. Coatings with fine spangle sizes and preferred parallel basal plane orientations developed networks of fine cracks during forming. The zinc coatings with fine cracks did not expose sufficient steel to cause accelerated galvanic corrosion.

Electrogalvanized coatings of three different weights (30, 70 and 100 g/m2) and hot dip Galfan® and Galvalume® coatings were characterized by scanning electron microscopy (SEM) and x-ray diffraction. Changes in surface morphology and texture in the coatings were monitored as a function of strain in uniaxial tension tests. The electrogalvanized coatings exhibited texture favorable for basal plane slip and consequently strong texture changes developed during straining. The ability to accomodate strain by plastic flow prevented cracking in the electrogalvanized coatings and ensured good substrate coverage except in the thinnest coating at high strains. The Galfan coatings had a strong basal plane texture and therefore an unfavorable orientation for plastic flow. As a result strain was primarily accomodated by cracking and texture changes with strain were minimal. Galvalume coatings accomodated strain by interdendritic cracking even at low strains, despite close-to-random texture in these zinc rich regions.

Optical absorption studies have been carried out from the UV to NIR for Ho3+ ions (0.1 M%) mixed organic acids namely anthrolinic, benzoic, salicylic and pthalic acids. Spectral intensities of various observed bands of Ho3+ have neen affected very significantly depending upon the surrounding environment. We made a correlation between the intensity parameters and the spectral intensities quite clearly by the application of Judd-Ofelt theory. Of the various levels recorded, particularly the energy level 5G6 ← 5I8 has shown a distinctive phenomenon in its intensity magnitudes as a function of the host. We have also examined the bonding nature of the complexes, as ionic for Ho3+ in four different fluorescing organic acids.

Abstract: Surface segregation behavior of solute atoms has been studied on low-carbon steels used in producing galvannealed sheet steels for automotive body panel applications. Samples of cold-rolled low-carbon steels with different amounts of carbon and phosphorus in solution were heated in a vacuum chamber and their surface chemistries analyzed by Auger electron spectroscopy. For the steels studied here, one or more of the elements carbon, phosphorus, and sulfur accumulated significantly at the surface within a temperature window of 300 to 973 K. As the temperature was increased, carbon appeared on the surface first, followed by phosphorus, and then sulfur. Each succeeding segregating element displaced the previous one from the surface. The free solute concentration in the bulk and the temperature were critical factors controlling the amount of solute accumulation at the surface. Once segregated, the solute atoms remained on the surface as the samples cooled. Carbon and/or boron in steels retarded the transport of phosphorus to the surface. The implications of these findings in understanding the galvannealing behavior of these steels are discussed.