Removal of congo red dye from water using carbon slurry waste

A cheaper adsorbent has been prepared from carbon slurry waste obtained from National Fertilizer Limited (NFL), Panipat and investigated for the removal of congo red, an anionic dye. Its adsorption on prepared carbonaceous adsorbent was studied as a function of contact time, concentration and temperature. The results have shown that carbonaceous adsorbent adsorbs dye to a sufficient extent (272mgg-1). A comparative study of adsorption results with those obtained on activated charcoal shows that the carbonaceous adsorbent is ~95% efficient as compared to activated charcoal. Thus, it can be fruitfully used for the removal of dyes from wastewater

Metformin induced yellow nails: a rare entity

This article reports an interesting and a rare case of metformin induced nail disorder in a middle aged female with type 2 diabetes. The patient had been receiving metformin one 1500mg daily from the last 6 months and noticed her finger nails gradually thickened and turned yellow. On stopping the metformin, the nails gradually normalized. The patient was treated further with glimepiride and insulin glargine. After 3 months of discontinuation of metformin there was a significant improvement in the nails. Clinicians should be aware of metformin induced yellow discolouration of nails, though a curable and reversible condition if diagnosed well in time

Efficacy of platelet rich plasma in comparison to steroid for the management of chronic plantar fasciitis

Background: Chronic plantar fasciitis is often a difficult to treat entity and platelet-rich plasma (PRP) is an upcoming modality instead of steroid in chronic cases of plantar fasciitis resistant to traditional non-operative management.Methods: Sixty patients with chronic plantar fasciitis were prospectively randomised into 2 groups and treated with either a single injection of 3 cc PRP or 40 mg DepoMedrol (Cortisone) injection and followed for a year. Immediately prior to PRP or cortisone injection American Orthopedic Foot and Ankle Society (AOFAS) hind foot scoring was done for all patients. These scores were repeated at 6 weeks, 6 months and 12 months.Results: Six weeks evaluation of AOFAS after PRP and corticosteroid administration, the mean visual analogue scale (VAS Score) showed a significant increase in corticosteroid group (4.2) as compared to PRP group (5.8). But, the PRP group (1.8) showed significant improvement in mean VAS scores as compared to Steroid group (3.4) after a year of the treatment. Similarly, the AOFAS score improved significantly in the steroid group (64.4) at 6wks as compared to the PRP group (52.2) but at 12 months however, the PRP group sustained its effect with a mean AOFAS score of 92.2 while in the steroid group, the score dropped to a mean of 78.4.Conclusions: PRP was more effective than steroid for the long term treatment of chronic plantar fasciitis. Level of Evidence: Level I, prospective randomized comparative series

Multimodal periarticular cocktail injection using steroid in total knee arthroplasty: a double blind randomised trial

Background: Multimodal periarticular cocktail injection (MPCI) containing local anesthetics, adrenaline, and anti-inflammatory agents such as NSAIDS have been promising in terms of quick functional recovery. This study evaluates the efficiency of steroid as a component of MPCI in knee arthroplasty.Methods: This is a prospective, double-blind, RCT where 36 patients with osteoarthritis were included and randomized to receive MPCI either with steroid or without steroid. Pain was evaluated by visual analogue scale (VAS) at preoperative and postoperatively at rest, and during activity. The range of motion of the knee was looked for in a similar way. The amount of NSAIDs and the duration of NSAID usage were noted till the last follow-up.Results: Both non-steroid and steroid groups were similar with regard to VAS at rest and during activity, or range of motion, at all postoperative observations. The postoperative knee society knee score in the steroid group improved significantly as compared to that in non-steroid group at the one-month (84.1±13.1 and 65.9±12.1; p<0.0045) and three-month follow-up (90.2±16.3 and 72.5±16.6; p<0.0027), but no significant difference was noted at six-month follow up. There was no significant difference in consumption of NSAIDs within 72 hours between the two groups. The duration of piroxicam usage in patients in the steroid group was significantly shorter than that in the non-steroid group, (7.2±0.7) compared with (10.5±1.9) weeks; =0.012.Conclusions: The Study validates usage of steroid in MPCI due to faster rehabilitation and less consumption of NSAIDs and no additional risk of post-operative complications.

Sub-monolayer growth of Ag on flat and nanorippled SiO2 surfaces

In-situ Rutherford Backscattering Spectrometry (RBS) and Molecular Dynamics (MD) simulations have been used to investigate the growth dynamics of silver on a flat and the rippled silica surface. The calculated sticking coeficient of silver over a range of incidence angles shows a similar behaviour to the experimental results for an average surface binding energy of a silver adatom of 0.2 eV. This value was used to parameterise the MD model of the cumulative deposition of silver in order to understand the growth mechanisms. Both the model and the RBS results show marginal difference between the atomic concentration of silver on the at and the rippled silica surface, for the same growth conditions. For oblique incidence, cluster growth occurs mainly on the leading edge of the rippled structure

Thermal dynamics of silver clusters grown on rippled silica surfaces

Silver nanoparticles have been deposited on silicon rippled patterned templates at an angle of incidence of 70° to the surface normal. The templates are produced by oblique incidence argon ion bombardment and as the fluence increases, the periods and heights of the structures increase. Structures with periods of 20 nm, 35 nm and 45 nm have been produced. Moderate temperature vacuum annealing shows the phenomenon of cluster coalescence following the contour of the more exposed faces of the ripple for the case of 35 nm and 45 nm but not at 20 nm where the silver aggregates into larger randomly distributed clusters. In order to understand this effect, the morphological changes of silver nanoparticles deposited on an asymmetric rippled silica surface are investigated through the use of molecular dynamics simulations for different deposition angles of incidence between 0° and 70° and annealing temperatures between 500 K and 900 K. Near to normal incidence, clusters are observed to migrate over the entire surface but for deposition at 70°, a similar patterning is observed as in the experiment. The random distribution of clusters for the periodicity of 20 nm is linked to the geometry of the silica surface which has a lower ripple height than the longer wavelength structures. Calculations carried out on a surface with such a lower ripple height also demonstrate a similar effect

The dynamic connectedness between risk and return in the Fintech market of India : evidence using the GARCH-M approach

Fintech allows investors to explore previously unavailable investment opportunities; it provides new return opportunities while also introducing new risks. The aim of this study is to investigate the relationship between risk and return in the fintech industry in the Indian stock market. This article is based on market-based research that focuses on demonstrating the volatility in the fintech market’s prices and demystifying the opportunities. Secondary data were collected from the Bombay Stock Exchange’s official fintech industry website from January 2017 to July 2022 to determine whether there is any dynamic link between risk and return in the Indian fintech market. The variance-based Mean-GARCH (GARCH-M) model was used to determine whether there is a dynamic link between risk and return in the Indian fintech market. The findings emphasize the importance of taking the risk of investing in India’s fintech industry. The implications for stock investors’ and fund managers’ portfolio composition and holding periods of equities or market exposure are significant. Finally, depending on their investment horizons, the Indian fintech industry may yield significant profits for risk-taking individuals.peer-reviewe

Temperature induced modulation of resonant Raman scattering in bilayer 2H-MoS2_{2}

The temperature evolution of the resonant Raman scattering from high-quality bilayer 2H-MoS$_{2}$ encapsulated in hexagonal BN flakes is presented. The observed resonant Raman scattering spectrum as initiated by the laser energy of 1.96 eV, close to the A excitonic resonance, shows rich and distinct vibrational features that are otherwise not observed in non-resonant scattering. The appearance of 1$^{st}$ and 2$^{nd}$ order phonon modes is unambiguously observed in a broad range of temperatures from 5 K to 320 K. The spectrum includes the Raman-active modes, $i.e.$ E$_\textrm{1g}^{2}$($\Gamma$) and A$_\textrm{1g}$($\Gamma$) along with their Davydov-split counterparts, $i.e.$ E$_\textrm{1u}$($\Gamma$) and B$_\textrm{1u}$($\Gamma$). The temperature evolution of the Raman scattering spectrum brings forward key observations, as the integrated intensity profiles of different phonon modes show diverse trends. The Raman-active A$_{1g}$($\Gamma$) mode, which dominates the Raman scattering spectrum at $T$=5~K quenches with increasing temperature. Surprisingly, at room temperature the B$_\textrm{1u}$($\Gamma$) mode, which is infrared-active in the bilayer, is substantially stronger than its nominally Raman-active A$_\textrm{1g}$($\Gamma$) counterpart.Comment: 7 pages, 3 figure

Analogy and dissimilarity of excitons in monolayer and bilayer of MoSe2_2

Excitons in thin layers of semiconducting transition metal dichalcogenides are highly subject to the strongly modified Coulomb electron-hole interaction in these materials. Therefore, they do not follow the model system of a two-dimensional hydrogen atom. We investigate experimentally and theoretically excitonic properties in both the monolayer (ML) and the bilayer (BL) of MoSe$_2$ encapsulated in hexagonal BN. The measured magnetic field evolutions of the reflectance contrast spectra of the MoSe$_2$ ML and BL allow us to determine $g$-factors of intralayer A and B excitons, as well as the $g$-factor of the interlayer exciton. We explain the dependence of $g$-factors on the number of layers and excitation state using first principles calculations. Furthermore, we demonstrate that the experimentally measured ladder of excitonic $s$ states in the ML can be reproduced using the $\mathbf{k\cdot p}$ approach with the Rytova-Keldysh potential that describes the electron-hole interaction. In contrast, the analogous calculation for the BL case requires taking into account the out-of-plane dielectric response of the MoSe$_2$ BL.Comment: 10 pages, 4 figures, + S

Broadband and Tunable Light Harvesting in Nanorippled MoS2 Ultrathin Films

Nanofabrication of flat optic silica gratings conformally layered with two-dimensional (2D) MoS2 is demonstrated over large area (cm2), achieving a strong amplification of the photon absorption in the active 2D layer. The anisotropic subwavelength silica gratings induce a highly ordered periodic modulation of the MoS2 layer, promoting the excitation of Guided Mode Anomalies (GMA) at the interfaces of the 2D layer. We show the capability to achieve a broadband tuning of these lattice modes from the visible (VIS) to the near-infrared (NIR) by simply tailoring the illumination conditions and/or the period of the lattice. Remarkably, we demonstrate the possibility to strongly confine resonant and nonresonant light into the 2D MoS2 layers via GMA excitation, leading to a strong absorption enhancement as high as 240% relative to a flat continuous MoS2 film. Due to their broadband and tunable photon harvesting capabilities, these large area 2D MoS2 metastructures represent an ideal scalable platform for new generation devices in nanophotonics, photo- detection and -conversion, and quantum technologies