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Bi-layer epitaxial graphene (BLG) on 6H-SiC(0001) (EG/SiC) was grown and modified by thermal deposition of the molecular electron acceptor tetrafluoro-tetra cyano quinodimethane (F4-TCNQ). The surface-modified system, F4-TCNQ/EG/SiC, was studied by X-ray photoelectron spectroscopy (XPS) and angle-resolved polarized Raman spectroscopy (ARPRS). XPS results indicate that bonding of deposited F4-TCNQ molecules depends on their concentration. Although bonding through the cyano groups is present at all concentrations, charge transfer from graphene to fluorine is evident only at sub-monolayer concentrations. The corresponding change in bond character is coupled with a change in molecular orientation. Raman spectroscopy not only provides results consistent with the findings from the XPS study but also reveals a significant degree of molecular stacking above the monolayer concentration. Thus, both the variation of the acceptor concentration and the number of graphene layers provide further handles to manipulate charge and doping that may be useful in device applications.

COVID-19 is a systemic disease affecting multiple organ systems and caused by infection with the SARS-CoV-2 virus. Two years into the COVID-19 pandemic and after the introduction of several vaccines, the pandemic continues to evolve in part owing to global inequities in access to preventive and therapeutic measures. We are also witnessing the introduction of antivirals against COVID-19. Against this current background, we review the progress made with nanotechnology-based approaches such as nanoformulations to combat the multiorgan effects of SARS-CoV-2 infection from a systems medicine lens. While nanotechnology has previously been widely utilized in the antiviral research domain, it has not yet received the commensurate interest in the case of COVID-19 pandemic response strategies. Notably, SARS-CoV-2 and nanomaterials are similar in size ranging from 50 to 200 nm. Nanomaterials offer the promise to reduce the side effects of antiviral drugs, codeliver multiple drugs while maintaining stability in the biological milieu, and sustain the release of entrapped drug(s) for a predetermined time period, to name but a few conceivable scenarios, wherein nanotechnology can enable and empower preventive medicine and therapeutic innovations against SARS-CoV-2. We conclude the article by underlining that nanotechnology-based interventions warrant further consideration to enable precision planetary health responses against the COVID-19 pandemic.

We have performed a detailed analysis on the Teutsch 76 (T76) open cluster using the deep near-infrared (NIR) observations taken with the TANSPEC instrument mounted on the 3.6m Devasthal Optical Telescope (DOT) along with the recently available high quality proper motion data from the {\it Gaia} data release 3 and deep photometric data from Pan-STARRS1 survey. We have found that the T76 cluster is having a central density concentration with circular morphology, probably due to the star formation processes. The radius of the T76 cluster is found to be 45$^{\prime}{^\prime}$ (1.24 pc) and 28 stars within this radius were marked as highly probable cluster members. We have found that the cluster is located at a distance of $5.7\pm1.0$ kpc and is having an age of $50\pm10$ Myr. The mass function slope ($Γ$) in the cluster region in the mass range $\sim$0.75$, Accepted for publication in Journal of Astrophysics and Astronomy

Using optical photometric observations from 1.3m Devasthal Fast Optical Telescope and deep near-infrared (NIR) photometric observations from TANSPEC mounted on 3.6m Devasthal Optical Telescope, along with the multi-wavelength archival data, we present our study of open cluster Kronberger 55 to understand the star formation scenario in the region. The distance, extinction and age of the cluster Kronberger 55 are estimated as ~3.5 kpc, E(B-V)~1.0 mag and $\lesssim$55 Myr, respectively. We identified Young Stellar Objects (YSOs) based on their excess infrared (IR) emission using the two-color diagrams (TCDs). The mid-infrared (MIR) images reveal the presence of extended structure of dust and gas emission along with the outflow activities in the region with two peaks, one at the location of cluster Kronberger 55 and another at 5'.35 southwards to it. The association of radio continuum emission with the southern peak, hints towards the formation of massive star/s. The Herschel sub-millimeter maps reveal the presence of two clumps connected with a filamentary strcuture in this region, and such configuration is also evident in the 12CO(1-0) emission map. Our study suggests that this region might be a hub-filament system undergoing star formation due to the 'end-dominated collapse scenario'., 14 pages, 11 figures, Accepted in Journal of Astrophysics and Astronomy (JAA)

The TIFR Near Infrared Imaging Camera-II (TIRCAM2) is being used at the Devasthal Optical Telescope (DOT) operated by Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital, Uttarakhand, India. In addition to the normal full frame observations, there has been a requirement for high speed sub-array observations for applications such as lunar occultation and star speckle observations. Fast sub-array modes have been implemented in TIRCAM2 with suitable changes in the camera software at the computer and controller DSP code level. Successful observations have been carried out with the fast sub-array mode of observation., Comment: Accepted for publication in the Journal of Astrophysics and Astronomy, special issue

Phosphorus is an essential nutrient for crops. Precise spatiotemporal application of P fertilizer can improve plant P acquisition and reduce run‐off losses of P. Optimizing application would benefit from understanding the dynamics of P release from a fertilizer pellet into bulk soil, which requires space‐ and time‐resolved measurements of P concentration in soil solutions. In this study, we combined microdialysis and X‐ray computed tomography to investigate P transport in soil. Microdialysis probes enabled repeated solute sampling from one location with minimal physical disturbance, and their small dimensions permitted spatially resolved monitoring. We observed a rapid initial release of P from the source, producing high dissolved P concentrations within the first 24 h, followed by a decrease in dissolved P over time compatible with adsorption onto soil particles. Soils with greater bulk density (i.e., reduced soil porosity) impeded the P pulse movement, which resulted in a less homogeneous distribution of total P in the soil column at the end of the experiment. The model fit to the data showed that the observed phenomena can be explained by diffusion and adsorption. The results showed that compared with conventional measurement techniques (e.g., suction cups), microdialysis measurements present a less invasive alternative. The time‐resolved measurements ultimately highlighted rapid P dynamics that require more attention for improving P use efficiency., Core Ideas The initial release of P from fertilizer pellets is not well studiedMicrodialysis and X‐ray CT permit noninvasive time‐resolved monitoringA lab‐scale setup was used to study solution P concentrations in time and spaceA rapid initial release of P from the pellet was measured, with no replenishmentP concentration decreased over time, compatible with adsorption onto soil

We present the design and performance of the TANSPEC, a medium-resolution $0.55-2.5~\mu$m cryogenic spectrometer and imager, now in operation at the 3.6-m Devasthal Optical Telescope (DOT), Nainital, India. The TANSPEC provides three modes of operation which include, photometry with broad- and narrow-band filters, spectroscopy with short slits of 20$^{\prime \prime}$ length and different widths (from 0.5$^{\prime \prime}$ to 4.0$^{\prime \prime}$) in cross-dispersed mode at a resolving power R of $\sim$2750, and spectroscopy with long slits of 60$^{\prime \prime}$ length and different widths (from 0.5$^{\prime \prime}$ to 4.0$^{\prime \prime}$) in prism mode at a resolving power R of $\sim$100-350. TANSPEC's imager mode provides a field of view of 60$^{\prime \prime} \times 60^{\prime \prime}$ with a plate scale of 0.245$^{\prime \prime}$/pixel on the 3.6-m DOT. The TANSPEC was successfully commissioned during April-May 2019 and the subsequent characterization and astronomical observations are presented here. The TANSPEC has been made available to the worldwide astronomical community for science observations from October 2020., Comment: 35 pages, Accepted for publication in - Publications of the Astronomical Society of the Pacific (PASP)

We present a multiwavelength study of the H II region Sh 2-301 (S301) using deep optical data, near-infrared data, radio continuum data and other archival data at longer wavelengths. A cluster of young stellar objects (YSOs) is identified in the north-east (NE) direction of S301. The H{\alpha} and radio continuum images trace the distribution of the ionized gas surrounding a massive star ALS 207, and the S301 H II region is bounded by an arc-like structure of gas and dust emission in the south-eastern direction. The north-western part of S301 seems to be devoid of gas and dust emission, while the presence of molecular material between the NE cluster and the central massive star ALS 207 is found. The distribution of warm dust emission, ionized gas, and neutral hydrogen together suggests a blistered morphology of the S301 H II region powered by ALS 207, which appears to be located near the edge of the cloud. The location of the NE cluster embedded in the cold molecular cloud is found opposite to the blistered morphology. There is a noticeable age difference investigated between the massive star and the NE cluster. This age difference, pressure calculation, photodissociation regions (PDRs), and the distribution of YSOs favour the positive feedback of the massive star ALS 207 in S301. On a wider scale of S301, the H II region and the young stellar cluster are depicted toward the central region of a hub-filamentary system, which is evident in the infrared images., Comment: Accepted for publication in ApJ

Phosphorus (P) is a limiting nutrient for crops and it is therefore highly managed in human activities such as agriculture. Not only the global phosphate rock reserves are going to be exhausted in a century, but P can also be lost from fields with the runoff ending up contaminating water bodies and causing eutrophication. This study is aimed at investigating P release from a fertiliser granule at high spatial and temporal resolution to optimise fertilisation timing, match crop requirements and reduce runoff. Experimental data consist of time-resolved P concentration in the soil solution at three different depths and total P concentration profile determined via total soil digestion. We observed a rapid, single-pulse release of P from the fertiliser granule shortly after soil wetting ( As the experimental data did not match the model-predicted P diffusion behaviour, a new modelling approach was used to reproduce the data. The model accounts for P diffusion and adsorption onto soil particles, resulting in the temporal evolution of P concentrations both in the soil solution and adsorbed onto soil particles. As the final total P concentration in soil reflects the initial P concentration profile in the soil solution, the model shows that adsorption onto soil particles happens faster than diffusion. Additionally, the model gives an estimate of diffusion, adsorption and desorption rates, as well as the maximum distance that P can travel from the source. Combining high-resolution experiments with modelling provided a new insight into P release and diffusion from a fertiliser granule. The results can inform optimal fertilisation timings to improve crop yields while reducing P application rates and undesirable side effects such as eutrophication.

The Gaia Alert System issued an alert on 2020 August 28, on Gaia 20eae when its light curve showed a $\sim$4.25 magnitude outburst. We present multi-wavelength photometric and spectroscopic follow-up observations of this source since 2020 August and identify it as the newest member of the FUor/EXor family of sources. We find that the present brightening of Gaia 20eae is not due to the dust clearing event but due to an intrinsic change in the spectral energy distribution. The light curve of Gaia 20eae shows a transition stage during which most of its brightness ($\sim$3.4 mag) has occurred at a short timescale of 34 days with a rise-rate of 3 mag/month. Gaia 20eae has now started to decay at a rate of 0.3 mag/month. We have detected a strong P Cygni profile in H$\alpha$ which indicates the presence of winds originating from regions close to the accretion. We find signatures of very strong and turbulent outflow and accretion in Gaia 20eae during this outburst phase. We have also detected a red-shifted absorption component in all the Ca II IR triplet lines consistent with signature of hot in-falling gas in the magnetospheric accretion funnel. This enables us to constrain the viewing angle with respect to the accretion funnel. Our investigation of Gaia 20eae points towards magnetospheric accretion being the phenomenon for the current outburst., Comment: 17 pages, 11 figures, Accepted in Astrophysical Journal

The COVID-19 pandemic has affected 215 countries and territories around the world with 60,187,347 coronavirus cases and 17,125,719 currently infected patients confirmed as of the 25th of November 2020. Currently, many countries are working on developing new vaccines and therapeutic drugs for this novel virus strain, and a few of them are in different phases of clinical trials. The advancement in high-throughput sequence technologies, along with the application of bioinformatics, offers invaluable knowledge on genomic characterization and molecular pathogenesis of coronaviruses. Recent multi-disciplinary studies using bioinformatics methods like sequence-similarity, phylogenomic, and computational structural biology have provided an in-depth understanding of the molecular and biochemical basis of infection, atomic-level recognition of the viral-host receptor interaction, functional annotation of important viral proteins, and evolutionary divergence across different strains. Additionally, various modern immunoinformatic approaches are also being used to target the most promiscuous antigenic epitopes from the SARS-CoV-2 proteome for accelerating the vaccine development process. In this review, we summarize various important computational tools and databases available for systematic sequence-structural study on coronaviruses. The features of these public resources have been comprehensively discussed, which may help experimental biologists with predictive insights useful for ongoing research efforts to find therapeutics against the infectious COVID-19 disease., Graphical abstract Image 1, Highlights • This review presents a comprehensive and up-to-date overview of newly developed computational resources including tools and web servers focused on coronaviruses. • We have categorized these popular tools and databases depending on the utility and application such as for coronavirus detection, comparative genomics analysis, vaccine and drug discovery, molecular docking, tools for SARS-CoV-2 detection, and other applications in coronaviruses study. • The features of each of the tools have been discussed along with their application in recent coronavirus research studies.

High resolution infrared imaging observations of the young planetary nebulae (PNe) NGC 7027 and BD +30° 3639, taken with the newly installed TIFR near infrared camera-II (TIRCAM2) on 3.6 m Devasthal optical telescope (DOT), ARIES, Nainital, are being reported. The images are acquired in J, H, K, polycyclic aromatic hydrocarbon (PAH) and narrow-band L (nbL) filters. The observations show emission from warm dust and PAHs in the circumstellar shells. The imaging of the two objects are among the first observations in PAH and nbL bands using TIRCAM2 on DOT. The NGC 7027 images in all bands show similar elliptical morphology with $$\sim $$ 6 $$^{\prime \prime }$$ .7 and $$\sim $$ 4 $$^{\prime \prime }$$ .5 semi-major and semi-minor axes. Considering size up to 10% of peak value the nebula extends upto 8 $$^{\prime \prime }$$ from the central star revealing a multipolar evolution. The relatively cooler BD +30° 3639 shows a rectangular-ring shaped nebula. In J and H bands it shows an angular diameter of $$\sim $$ 8 $$^{\prime \prime }$$ , while a smaller $$\sim $$ 6 $$^{\prime \prime }$$ .9 size is observed in K, PAH and nbL bands. The 3.28 $$\mu $$ m emission indicates presence of PAHs at about 6000 and 5000 AU from the central stars in NGC 7027 and BD +30° 3639 respectively. Analysis suggests domination of neutral PAHs in BD +30° 3639, while in NGC 7027 there is higher ionization and more processed PAH population.

In this paper, we propose a modular approach to estimate the position and rotation of any mobile robot more precisely in an indoor environment using text and sign recognition. The modular approach for the text and sign recognition is performed in a twofold method in figure 1. First is the detection of the region with texts and various signs in the image which is done by an object detection system. The second part is the character recognition, where the detected textual region from the image will be passed onto an optical character recognition engine(OCR) engine to be recognized. This modular approach can be modified at any point based on any mobile robot in an indoor environment with texts and signs to help localize its position and rotation.

As recent research on deep learning methods has been actively conducted, a number of deep learning methods have been proposed. In this paper, we propose a method of removing the desired object from an image using generative adversarial networks(GANs) structure. We composed the network in which two GANs are fused. The first GAN erases the target object from the input image, and the second GAN generates an image that fills the empty space with the background. Through this network, we can erase the desired object from the input image and get an image with the erased part filled with the background without any object detection method. We show that the removal of people and vehicles from images of roads using the CityScapes Dataset.

Phosphorus (P) is a development-limiting nutrient for crops, hence global food production relies on P fertilizer application. However, P mobility in soil depends on many abiotic and biological processes, most notably its chemical interactions with the soil particles. Optimizing the timing and amount of fertilization could lead to higher production efficiencies and also reduce P runoff and subsequent contamination of water bodies. Plants have developed strategies to improve P uptake by optimizing the root system architecture and exuding organic acids for enhancing P mining locally to the root tips. However, these adaptations are mainly a response to low P availability or to already immobilized P patches in soil, and little is known about the fate of P in the early stages of fertilization.In this framework, we developed an experimental assay for investigating P release from the fertilizer pellets, and its movement through soil using non-invasive microdialysis sampling techniques and inductively coupled plasma - mass spectrometry (ICP-MS) analytical techniques. Microdialysis allowed for time resolved in-situ samplings and the small size of the probes also allows for a fine spatial resolution.Results showed a very rapid release of the P from the fertilizer pellet (triple super phosphate, TSP), producing a high concentration pulse that lasts a few hours. P concentrations then decrease over time until reaching steady low concentrations after 6-8 days and P replenishment from the pellet was not observed after the first pulse. The experiments showed that the speed of P movement in soil is greatly influenced by soil particle size distribution, and that gravity plays an important role in promoting quick P movement in the downward direction, while diffusion can account for P observed in the upward direction. Modelling was also applied to data fitting for quantifying trends and deriving an effective P diffusion coefficient in saturated soil.

We present a one-dimensional model describing the blood flow through a moderately curved and elastic blood vessel. We use an existing two dimensional model of the vessel wall along with Navier-Stokes equations to model the flow through the channel while taking factors, namely, surrounding muscle tissue and presence of external forces other than gravity into account. Our model is obtained via a dimension reduction procedure based on the assumption of thinness of the vessel relative to its length. Results of numerical simulations are presented to highlight the influence of different factors on the blood flow. (C) 2018 Elsevier Inc. All rights reserved. Funding Agencies|Russian Foundation of Basic Research [18-01-00325]

We present a two-dimensional model describing the elastic behaviour of the wall of a curved flexible pipe. The wall has a laminate structure consisting of several anisotropic layers of varying thic ...

Using our deep optical and near-infrared photometry along with multiwavelength archival data, we here present a detailed study of the Galactic H II region Sh 2-305, to understand the star/star-cluster formation. On the basis of excess infra-red emission, we have identified 116 young stellar objects (YSOs) within a field of view of ~ 18.5 arcminute x 18.5 arcminute, around Sh 2-305. The average age, mass and extinction (A_V) for this sample of YSOs are 1.8 Myr, 2.9 solar mass and 7.1 mag, respectively. The density distribution of stellar sources along with minimal spanning tree calculations on the location of YSOs reveals at least three stellar sub-clusterings in Sh 2-305. One cluster is seen toward the center (i.e., Mayer 3), while the other two are distributed toward the north and south directions. Two massive O-type stars (VM2 and VM4; ages ~ 5 Myr) are located at the center of the Sh 2-305 H II region. The analysis of the infrared and radio maps traces the photon dominant regions (PDRs) in the Sh 2-305. Association of younger generation of stars with the PDRs is also investigated in the Sh 2-305. This result suggests that these two massive stars might have influenced the star formation history in the Sh 2-305. This argument is also supported with the calculation of various pressures driven by massive stars, slope of mass function/K-band luminosity function, star formation efficiency, fraction of Class I sources, and mass of the dense gas toward the sub-clusterings in the Sh 2-305.

Up-scaling technologies for use during the processing of waste materials offer the hope of a sustainable environment. Under an optimistic scenario, recycling and reuse of waste materials, especially food waste, may reverse the global shortage of raw materials. In contrast to previous strategies, the biorefinery concept could be a reality, through which abandoned food waste could be saved from landfills and turned into biomaterials, including biochemicals and biofuels. The nature of feedstock and the valorization pathway are used to determine the overall production cost of the process and thus the market value. The opportunities and challenges for attaining market value for these valorized products are highlighted. This chapter also discusses an integrated product policy, an EU policy that is in agreement with the market in such a way that it creates incentives for companies by encouraging the continuous supply of and demand for valorized final products.

The problem of mathematical modelling of incompressible flows with low velocities through narrow curvilinear pipes is addressed in this thesis. The main motivation for this modelling task is to eve ...

A modified Reynolds equation governing the steady flow of a fluid with low Reynolds number through a curvilinear, narrow tube, with its derivation from Stokes equations through asymptotic methods is presented. The channel considered may have large curvature and torsion. Approximations of the velocity and the pressure of the fluid inside the channel are constructed by artificially imposing appropriate boundary conditions at the inlet and the outlet. A justification for the approximations is provided along with a comparison with a simpler case., Comment: 21 pages, 1 figure

Tata Institute of Fundamental Research (TIFR) Near Infrared Imaging Camera-II (TIRCAM2) is a closed-cycle Helium cryo-cooled imaging camera equipped with a Raytheon 512[Formula: see text][Formula: see text][Formula: see text]512 pixels InSb Aladdin III Quadrant focal plane array (FPA) having sensitivity to photons in the 1–5[Formula: see text][Formula: see text] wavelength band. In this paper, we present the performance of the camera on the newly installed 3.6[Formula: see text]m Devasthal Optical Telescope (DOT) based on the calibration observations carried out during 2017 May 11–14 and 2017 October 7–31. After the preliminary characterization, the camera has been released to the Indian and Belgian astronomical community for science observations since 2017 May. The camera offers a field-of-view (FoV) of [Formula: see text] on the DOT with a pixel scale of 0.169[Formula: see text]. The seeing at the telescope site in the near-infrared (NIR) bands is typically sub-arcsecond with the best seeing of [Formula: see text] realized in the NIR [Formula: see text]-band on 2017 October 16. The camera is found to be capable of deep observations in the [Formula: see text], [Formula: see text] and [Formula: see text] bands comparable to other 4[Formula: see text]m class telescopes available world-wide. Another highlight of this camera is the observational capability for sources up to Wide-field Infrared Survey Explorer (WISE) W1-band (3.4[Formula: see text][Formula: see text]m) magnitudes of 9.2 in the narrow [Formula: see text]-band ([Formula: see text]; [Formula: see text] 3.59[Formula: see text][Formula: see text]m). Hence, the camera could be a good complementary instrument to observe the bright [Formula: see text]-band sources that are saturated in the Spitzer-Infrared Array Camera (IRAC) ([3.6] [Formula: see text] 7.92 mag) and the WISE W1-band ([3.4] [Formula: see text] 8.1 mag). Sources with strong polycyclic aromatic hydrocarbon (PAH) emission at 3.3[Formula: see text][Formula: see text]m are also detected. Details of the observations and estimated parameters are presented in this paper.

We consider the problem $\mathbf{P_{curve}}$ of minimizing $\int \limits_0^L \sqrt{\xi^2 + \kappa^2(s)} \, {\rm d}s$ for a curve $\mathbf{x}$ on $\mathbb R$ with fixed boundary points and directions. Here the total length $L\geq 0$ is free, $s$ denotes the arclength parameter, $\kappa$ denotes the absolute curvature of $\mathbf{x}$, and $\xi>0$ is constant. We lift problem $\mathbf{P_{curve}}$ on $\mathbb R^3$ to a sub-Riemannian problem $\mathbf{P_{mec}}$ on $\operatorname{SE(3)}\nolimits/(\{\mathbf{0}\}\times \operatorname{SO(2)}\nolimits)$. Here, for admissible boundary conditions, the spatial projections of sub-Riemannian geodesics do not exhibit cusps and they solve problem $\mathbf{P_{curve}}$. We apply the Pontryagin Maximum Principle (PMP) and prove Liouville integrability of the Hamiltonian system. We derive explicit analytic formulas for such sub-Riemannian geodesics, relying on the co-adjoint orbit structure, an underlying Cartan connection, and the matrix representation of $\operatorname{SE(3)}\nolimits$ arising in the Cartan-matrix. These formulas allow us to extract geometrical properties of the sub-Riemannian geodesics with cuspless projection, such as planarity conditions, explicit bounds on their torsion, and their symmetries. Furthermore, they allow us to parameterize all admissible boundary conditions reachable by geodesics with cuspless spatial projection. Such projections lay in the upper half space. We prove this for most cases, and the rest is checked numerically. Finally, we employ the formulas to numerically solve the boundary value problem, and visualize the set of admissible boundary conditions., Comment: 28 pages, 9 figures