Probing the spatial and velocity anisotropies in stellar halos from the Aquarius simulations

We analyze the spatial anisotropy and the velocity anisotropy in a set of mock stellar halos from the Aquarius simulations. The spatial anisotropy in each mock stellar halo rises progressively with the increasing distance from the halo centre, eventually reaching a maximum near the periphery. Excluding the bound satellites leads to a significant reduction of the spatial anisotropy in each halo. We compare the measured anisotropy in the mock stellar halos with that from their sphericalized versions where all the shape and substructure induced anisotropies are erased. The growth of spatial anisotropy persists throughout the entire halo when the bound satellites are present but remains limited within the inner halo ($<60 \, h^{-1}\, {\rm kpc}$) after their exclusion. This indicates that the spatial anisotropy in the inner halo is induced by the diffuse substructures and the halo shape whereas the outer halo anisotropy is dominated by the bound satellites. We find that the outer parts of the stellar halo are kinematically colder than the inner regions. The stellar orbits are predominantly radial but they become rotationally dominated at certain radii that are marked by the prominent $\beta$ dips. Most of the $\beta$ dips disappear after the removal of the satellites. A few shallow and broad $\beta$ dips arise occasionally due to the presence of diffuse streams and clouds. Our analysis suggests that a combined study of the spatial and velocity anisotropies can reveal the structure and the assembly history of the stellar halos.Comment: 15 pages, 9 figures, comments welcom

Coronal Elemental Abundances during A-class Solar Flares Observed by Chandrayaan-2 XSM

The abundances of low First Ionisation Potential (FIP) elements are three to four times higher (FIP bias) in the closed loop active corona than in the photosphere, known as the FIP effect. Observations suggest that the abundances vary in different coronal structures. Here, we use the soft X-ray spectroscopic measurements from the Solar X-ray Monitor (XSM) on board the Chandrayaan-2 orbiter to study the FIP effect in multiple A-class flares observed during the minimum of solar cycle 24. Using time-integrated spectral analysis, we derive the average temperature, emission measure, and the abundances of four elements - Mg, Al, Si, and S. We find that the temperature and emission measure scales with the flares sub-class while the measured abundances show an intermediate FIP bias for the lower A-flares (e.g., A1), while for the higher A-flares, the FIP bias is near unity. To investigate it further, we perform a time-resolved spectral analysis for a sample of the A-class flares and examine the evolution of temperature, emission measure, and abundances. We find that the abundances drop from the coronal values towards their photospheric values in the impulsive phase of the flares, and after the impulsive phase, they quickly return to the usual coronal values. The transition of the abundances from the coronal to photospheric values in the impulsive phase of the flares indicates the injection of fresh unfractionated material from the lower solar atmosphere to the corona due to chromospheric evaporation. However, explaining the quick recovery of the abundances from the photospheric to coronal values in the decay phase of the flare is challenging.Comment: Accepted for publication in 'Solar Physics

A Study of Kinematic Release Parameters of Male and Female Shot Putters

Today technique is equally the key to better performance, although we cannot escape the facts that "style" will always be an integral aspect in ultimate performance. This is due to the differences in the physical and anatomical structure of the human body, which differs from athlete to athlete.  The aim of the study was to gain understanding of the athlete performance and to communicate the knowledge to the coaches to generate accurate recommendation. The subjects for the study were selected from sports hostel in SAI (Salt Lake City). 05 male and 05 female national athletes were selected randomly and aged from 18 to 28 years. Each of them were given six trials and that best trial result was recorded for the analysis of various parameters. Such as:  height of release, angle of release, speed of release and horizontal release distance.  The above parameters were analyzed and calculated with the help of tracker 4.92 software. The actions of athletes were captured using cannon camera with 120fps speed and parameters like release velocity was calculated. The horizontal distance was calculated by reference tape. Result showed that male and female shot putters did not show any significant difference in angle of release of the shot and horizontal distance gained by the shot at release. The non significance difference in release angle of shot between male and female shot putters is in compliance with the basic mechanical principles

Role of Multipurpose Projects on Distribution of Cropping Intensity and Canal Irrigation: A Study on DVC Projects of the Middle Damodar River Valley of West Bengal

The river valley projects with many objectives are called multipurpose project. Multipurpose project in the Damodar River played a major role not only as a flood controller but also as a source of canal irrigation. Middle and lower course of the river are the most prominent area where irrigation systems are largely controlled by DVC projects of Damodar River. Several canal systems has also developed after construction of dams in DVC project of Damodar River Valley. The study area falls under the area in between Panchet Dam and Burdwan Town. It is extended up to 23º28’ N to 23º41’N latitude and 86 º 44 ’E to 87 º 18’ E longitudes. Total length of the area is approximately 70 km. the avg. height of this area is 110 m from the sea level. To show the increase of Agricultural Land in downstream section Damodar River Basin, block wise Cropping Intensity distribution has been calculated for showing locational and temporal. In this river valley, the area under Agricultural Land has been drastically increased (15%) from 1990 to 2010 but there are slightly increase in the Built up areas. The western side of the basin have the low cropping intensity in the Burdwan District. Upper reaches are less fertile that is why production is also low and reverse condition are found in the lower reaches of the river basin area. The downstream of the river valley are pure alluvial track of the Ganga River system and this region are more fertile than the upstream region. Whole basin area is bounded with agricultural and industrial activities. Irrigation also can put impetus on the agricultural output of this valley region especially in the downstream areas of the valley. Thus the dams are severally interlinked with the human settlement and landscapes of the Damodar Valley Region. Keywords: Multipurpose DVC projects, Agriculture, Dam and Barrage, Land use/land cover change, Cropping Intensity, Damodar River Valle

Azo dye degrading bacteria and their mechanism: A review

Major part of the aesthetics and beauty of idols, textiles, paper, paintings industries, etc. finds its roots in the use of colours (azo compound). These synthetic dyes can not degrade easily by physical and chemical means and are toxic for the environment and animals including humans. Even if they get degraded, it becomes difficult to get rid of the secondary toxic products.  Microbes especially bacteria can be used which results cheap, eco friendly and complete degradation of azo dye products without production of any secondary toxic products (or secondary products with way lesser toxicity). Also, it requires no new chemical to be added (in an attempt to degrade azo dye) in an already polluted environment, as the bacterial enzymes would do the job without requiring any other added chemicals. This review article discusses the use of bacteria for azo dye degradation, the bacterial enzymes such as laccase etc. that degrade azo dye and how they work to decolourise the dyes, the common genetic elements found in the different bacteria that can degrade azo dye. This article also includes information on future prospects and some genetically modified organism (GMO) that are being/ (can be) brought to use for dye degradation and pollution reduction

Numerical Solution of First-Order Linear Differential Equations in Fuzzy Environment by Runge-Kutta-Fehlberg Method and Its Application

The numerical algorithm for solving “first-order linear differential equation in fuzzy environment” is discussed. A scheme, namely, “Runge-Kutta-Fehlberg method,” is described in detail for solving the said differential equation. The numerical solutions are compared with (i)-gH and (ii)-gH differential (exact solutions concepts) system. The method is also followed by complete error analysis. The method is illustrated by solving an example and an application

Shell-Isolated Assembly of Atomically Precise Nanoclusters on Gold Nanorods for Integrated Plasmonic-Luminescent Nanocomposites

In this work, we integrate atomically precise noble metal nanoclusters (NCs) on gold nanorods (AuNRs) to create hybrid plasmonic-luminescent nanomaterials. Initially, we assemble luminescent Ag29(LA)12 NC (LA = lipoic acid) to silica shell-encapsulated AuNRs. The resulting nanostructure shows plasmon-enhanced luminescence in aqueous medium as well as in the solid state. Atomic precision of the fluorophores used in this case allows detailed characterization of individual nanocomposites by diverse techniques, including transmission electron microscopy (TEM) and 3D electron tomographic reconstruction. We extend this strategy to prepare similar structures with gold NC protected with bovine serum albumin (Au30BSA). These two examples demonstrate the generic nature of the present strategy in preparing plasmonic-luminescent hybrid nanostructures using atomically precise NCs.acceptedVersionPeer reviewe

Strong and Elastic Membranes via Hydrogen Bonding Directed Self-Assembly of Atomically Precise Nanoclusters

2D nanomaterials have provided an extraordinary palette of mechanical, electrical, optical, and catalytic properties. Ultrathin 2D nanomaterials are classically produced via exfoliation, delamination, deposition, or advanced synthesis methods using a handful of starting materials. Thus, there is a need to explore more generic avenues to expand the feasibility to the next generation 2D materials beyond atomic and molecular-level covalent networks. In this context, self-assembly of atomically precise noble nanoclusters can, in principle, suggest modular approaches for new generation 2D materials, provided that the ligand engineering allows symmetry breaking and directional internanoparticle interactions. Here the self-assembly of silver nanoclusters (NCs) capped with p-mercaptobenzoic acid ligands (Na4Ag44-pMBA30) into large-area freestanding membranes by trapping the NCs in a transient solvent layer at air–solvent interfaces is demonstrated. The patchy distribution of ligand bundles facilitates symmetry breaking and preferential intralayer hydrogen bondings resulting in strong and elastic membranes. The membranes with Young's modulus of 14.5 ± 0.2 GPa can readily be transferred to different substrates. The assemblies allow detection of Raman active antibiotic molecules with high reproducibility without any need for substrate pretreatment.publishedVersionPeer reviewe