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Cerebrospinal fluid (CSF) leak can occur immediately or several years after traumatic skull base injury which may present merely as a CSF leak or may even present with recurrent meningitis. Around 2% of all cases of head trauma, and 12%–30% of all basilar skull fractures may develop CSF leak. Posttraumatic CSF rhinorrhoea usually occurs within the first 48 hours, and the majority of them occur in the first 3 months, whereas delayed CSF leak beyond 3 months is rare. We encountered two such cases of delayed post-traumatic CSF rhinorrhoea about a decade after the head injury. We have reviewed and discussed previous studies on delayed post-traumatic CSF rhinorrhoea which have shown CSF leaks occur after months, years, or even after trauma. Such cases may help clinicians to be aware of the possibility of delayed CSF rhinorrhoea which may occur years after traumatic head injury.

Metal halide Pb-based and Pb-free perovskite crystal structures are an essential class of optoelectronic materials due to their significant optoelectronic properties, optical absorption and tuneable emission spectrum properties. However, the most efficient optoelectronic devices were based on the Pb as a monovalent cation, but its toxicity is a significant hurdle for commercial device applications. Thus, replacing the toxic Pb with Pb-free alternatives (such as tin (Sn)) for diverse photovoltaic and optoelectronic applications is essential. Moreover, replacing the volatile methylammonium (MA) with cesium (Cs) leads to the development of an efficient perovskite absorber layer with improved optical & thermal stability and stabilized photoconversion efficiency. This paper discusses the correlation between the experimental and theoretical work for the Pb-based and Pb-free perovskites synthesised using the hot-injection method at different temperatures. Here, simulation is also carried out using the help of SCAPS-1D software to study the effect of various parameters of CsSnI3 and CsPbI3 layers on solar cell performance. This experimental and theoretical comparative study of the Hot-injection method synthesised CsPbI3 and CsSnI3 perovskites is rarely investigated for optoelectronic applications.

Nowadays, the toxicity of lead in metal-halide perovskites is the most precarious obstruction in the commercialization of perovskite-based optoelectronic devices. However, Pb-free metal halide perovskites as environment-friendly materials because of their exceptional properties, such as band-gap tunability, narrow emission spectra, low toxicity and easy solution-processability, are potential candidates for optoelectronic applications. Recently, literature reported the poor structural stability and low-emission intensity of Bi-based perovskite NCs. Still, this paper focuses on the fabrication of Formamidinium (FA)-based Bi mixed halide and Methylammonium(MA)-based Bi-pure halide perovskites using Ligand-Assisted Reprecipitation Technique (LARP) technique. XRD diffraction patterns of FA-based perovskites were slightly broad, signifying the nanocrystalline form and limited size of perovskite nanocrystals. While the XRD diffraction patterns of MA3Bi2X9 (X = Cl/Br/I) perovskites were narrow, signifying the amorphous nature and larger size of perovskite nanocrystals. The peak positions were varied in MA-based bismuth halide perovskites with respect to the halide variation from Br to Cl to I ions. The optical study shows the variation in band gap and average lifetime with respect to halide variation leading to enhanced optical properties for device applications. The band-gap of FA3Bi2BrxCl1-x & FA3Bi2IxCl1-x perovskites was calculated to be around 3.7 & 3.8 eV, respectively, while in MA-halide perovskites the band-gap was calculated to be 2.8 eV, 3.1 eV & 3.4 eV with respect to halide variation from I to Cl to Br in perovskite samples using Tauc's plot respectively. Moreover, simulation is carried out using the SCAPS-1D software to study the various parameters in MA & FA-based Bi-pure or mixed halide perovskites. Here, we discussed the variation in efficiency with respect to the thickness variation from 100 to 500 nm for MA3Bi2I9 halide perovskites. These MA3Bi2I9 halide perovskites show minimum efficiency of 4.65 % at 100 nm thickness, while the perovskite sample exhibits maximum efficiency of 10.32 % at 500 nm thickness. Thus, the results stated that the thickness of absorber layers directly affects the device characteristics for optoelectronic applications.

The regulators based on PI control law continue to be the key elements in many of the industrial systems for their control. Likewise, the wind power generation systems (WPGSs) also make extensive use of PI regulators in their control schemes. The enhanced performance of these WPGS depends on proper selection of the PI regulator parameters. This paper deals with the control of a grid-tied permanent magnet synchronous generator (PMSG)-based WPGS wherein, a new attempt has been depicted to apply the most optimum design of the involved PI regulator parameters for the proposed WPGS based on standard performance indices making use of four popular optimization algorithms namely genetic algorithm (GA), cultural algorithm (CA), particle swarm optimization (PSO) and artificial bee colony (ABC). An informative discussion has also been presented which would be useful for practicing engineers/researchers to select flexibly and reasonably the PI regulators parameters meant for the control of the proposed WPGS. A detailed simulation model developed in MATLAB/Simulink has been used to analyze the performance of the proposed PMSG-based WPGS employed with the most optimum values of PI regulator parameters. The performances of WPGS have been compared while the most optimum PI regulator parameters have been included in the control system, and also when incorporating the PI regulator parameters in WPGS control designed via classical d-partition technique. The results obtained under gradually changing wind speed profile show the improvement in the performance of WPGS in terms of peak overshoot, time response and waveform oscillations. The experimental validation of the control performances have been carried out by way of real-time hardware-in-the-loop (HIL) testing making use of Typhoon HIL402 emulator and TMS320F28335 digital signal controller. The obtained real time HIL results are in close agreement to the results obtained in simulations using MATLAB/Simulink. A deviation of less than 4% was observed in the percentage overshoot/undershoot of the PMSG speed and DC link voltage determined through simulation and experimental means under various wind speed conditions.

In this experimental study, Sr2+-Co2+ was doped in Zn2Y-type hexaferrite to improve its magnetic and dielectric properties. Sol-gel auto combustion was used to synthesize Ba2-xSrxZn2-yCoyFe12O22 (x ​= ​0.0, 0.4, 0.8 and y ​= ​0.0, 0.5, 1.0), and the Retrieved refinement of XRD data confirmed the single-phase Y-type. Lattice constants a and c decreased from 5.867 to 5.854 Å and 43.566 to 43.470 Å, respectively. FTIR identified the absorption bands of hexaferrite at 405 cm-1 and 546 ​cm−1. An average grain size from FESEM decreased from 350 to 250 ​nm. Saturation magnetization and coercivity from M-H hysteresis loop for x ​= ​0.0, y ​= ​0.0, x ​= ​0.4, y ​= ​0.5, and x ​= ​0.8, y ​= ​1.0 are 40.04 emu/g, 42.77emu/g, 52.91emu/g, and 381.24 ​Oe, 261.44 ​Oe, 236.14 ​Oe respectively. The decrease in grain size, coercivity, and an increase in saturation magnetization make the prepared sample suitable for application in magnetic recording media. The material also deemed ideal for microwave devices due to its decreased dielectric constant values

Ferromagnetic properties of hexaferrites induce magnetisation inside their crystal structure, separating them into uniaxial and ferroxplana hexaferrites. Y-type is the first observed ferroxplana ferrite with spontaneous magnetization in the basal c-plane perpendicular to the c-axis. Y-type is a material class that exhibits a more comprehensive range of adjustable characteristics. This article provides a comprehensive overview of the synthesis methods to produce Y-type hexaferrite (A2Me2Fe12O22, where A can be Ba or Sr and Me is any divalent metal ion) and techniques used to characterize its properties. Due to the potential applications of Y-type hexaferrites, numerous authors synthesized several kinds of Y-type hexaferrite using a variety of metal substitutions for Me, Fe, and A. Most research on Y-type hexaferrite has concentrated on its structural and magnetic characteristics to investigate magnetoelectric and microwave (MW) device applications. In this review, we reported the suitability of Y-type hexaferrite for multiple applications in current information and communication processing equipment according to the previous findings.

Introduction. Pineal region pathologies are heterogenous, spectrum ranging from benign, infective to malignant in nature such as parenchymal, germ cell, glial, melanomas, metastatic, tubercular, etc. These lesions are commoner in the pediatric age group and have a variable outcome. The goal of this study is to present our experience regarding the surgical outcomes of pineal region lesions in the paediatric population. Objective. The objective of this study is to access the surgical outcome of pineal region lesions in the paediatric population Methods and Material. Eighty cases of pineal region lesions in the paediatric population (upto 15 years of age) operated in the neurosurgery department, G.B Pant Hospital New Delhi via either Occipital transtentorial or Supracerebellar Infratentorial approaches were retrospectively analyzed. Results. There were four main groups of lesions with pineal parenchymal tumours (35 cases) being the commonest. Glial tumours were the next most common contributing 29 cases. Germ cell tumours comprise 7 and miscellaneous 9 cases. The outcome showed graded improvement with the extent of tumour removal and 57 patients(71.25%) improved following surgery. The clinical status of 20 patients(25%) remained unchanged and 3(3.75%) deteriorated from their pre-operative status. 3 patients(3.75%) died in the immediate post-operative period and 11(13.75%) died due to recurrent disease. Conclusion. A graded increase in survival was noted with increasing the degree of resection and postoperative adjuvant therapy in malignant pineal tumours whereas benign pineal lesions can be managed with surgery. Pure germinomas are the only tumour for which the survival rate was unrelated to extent of tumour resection.

COVID-19 belongs to a typical class of viruses that predominantly affects the human respiratory system, thereby proving to be fatal to many. The virus, along with other air pollutant particulates poses a severe threat to the human respiratory organs. Since the most common transmission mode is respiratory fomites and aerosol particulates, it is necessary to prevent their ingression through a mask. The primary use of masks is to prevent aerial particulates. This paper reveals the development of masks with air filters coated with functionalized graphene (fG) mounted on a 3D-printed facial mask replica. The fused deposition modeling (FDM) process is used for fabricating the facial mask replica. fG associated with nanosheets has an additional adsorbing capacity with a high surface area to volume ratio. fG coat is used over a polypropylene (PP) cloth through a dip coating method to enhance the antiviral and antimicrobial properties. The quality of fG was investigated through Raman spectroscopy and other characterization techniques such as SEM, XRD, and FTIR, which were used for visual interpretation of distributions of fG on a polypropylene (PP) fabric. Fabricated fG coated MB filters show 98.2% of bacterial filtration efficiency with 1.10 mbar of breathing resistance. The efficacy of the fG coated filter was tested against SARS-CoV-2 viral particles, which showed a complete arrest of viral transmission at the fG coated layer.

BackgroundDuring the second wave of the COVID-19 pandemic in India, the Ministry of Ayush conducted a community study to provide therapeutic care to patients with asymptomatic, mild, and moderate COVID-19 in home isolation based on the empirical evidence generated on the efficacy of AYUSH-64 in COVID-19.ObjectiveTo document disease characteristics, care-seeking behavior, and outcomes in patients with asymptomatic, mild, or moderate COVID-19 in home isolation who used AYUSH-64 for COVID-19.MethodsCross-sectional analysis of the data generated through a community study conducted in India from 08 May to 31 August 2021 was performed to study the disease characteristics, care-seeking behavior during home isolation, clinical outcomes, adverse events, and the association between various risk factors and clinical recovery during the study period. The data were collected through semi-structured questionnaires, available in electronic data collection format at the baseline, 7, 14, and 21 days. A logistic regression was performed to explore the relationship between relevant variables and clinical recovery.ResultsData from 64,642 participants were analyzed for baseline assessment, and final analysis was done for 49,770 participants. The mean age of the enrolled participants was 38.8 ± 11.7 years, and 8.4% had co-morbidities. AYUSH-64 was utilized as an add-on to the standard care by 58.3% of participants. Comparable clinical outcomes were observed in participants utilizing AYUSH-64 either as a standalone or as an add-on to standard care, in terms of clinical recovery, disease progression, the requirement for oxygen supplementation, hospitalization, ICU admission, and need for ventilator support. Younger age, having no co-morbidities or substance abuse, and having been vaccinated were associated with early clinical recovery than those who were older and not vaccinated.ConclusionsThe study findings suggest that AYUSH-64 use, either standalone or as an adjunct to standard care, in asymptomatic, mild, or moderate COVID-19 is associated with good clinical outcomes. Ayush services and interventions can be effectively integrated into the mainstream public health architecture to serve public health goals.

World produces annually multimillion of tones of fly ash (FA) and red mud (RM) as industrial wastes. There is a dire need to develop a process that can potentially use these wastes as large stockpiling of these materials can lead a potential hazard to the common people. The FA is rich in silica and alumina, two major ingredients of the aluminosilicate network containing inorganic polymer called geopolymer. The present work demonstrates the geopolymer prepared from fly ash and red mud (FA-RM-geopolymer) with significant high strength of 65 MPa under optimized experimental conditions. Geopolymers were synthesized from the raw material under ambient condition of 25 °C with 28 day of curing. It was observed that after 28 days of curing maximum compressive strength of 65 MPa was achieved in presence of 10 wt percent of red mud. While fly ash based geopolymer (FA-geopolymer) showed 53 MPa compressive strength under similar experimental conditions. X-ray photoelectron spectroscopy (XPS), X-ray diffraction spectroscopy (XRD), particle size analysis and FE-SEM were used to study the structural properties of raw material and the geopolymer. XPS studies revealed that the iron of the RM does not take part in the geopolymerization, as no change was observed for the Fe2p3/2 peak of the RM and FA-RM-geopolymer. However significant change was observed for the Al2p3/2 XPS peak. Further it was observed that the presence of RM resulted in increases Si/Al and Na/Al molar ratio compared to FA-geopolymer. SEM studies confirmed the formation of high dense structure for the FA-RM-geopolymer suggesting RM provides aluminum to participate in the geopolymerization and simultaneously acts as filler thereby leads to enhanced and active geopolymerization process on blending of fly ash with red mud.

316 L Stainless steel is widely used industrial material having application in broad range of domain including automotive, structural as well as biomedical. It is also used for several high temperature applications in various industries, permanent deformation due to thermal cycling and continuous high temperature exposure is one of the major concern in industries. Therefore, enticing thermo physical properties is very crucial for better efficiency and service life of components. In the present work, graphene reinforced 316 L metal matrix composite was prepared via powder bed fusion additive manufacturing technique in order to make it more stable material at elevated temperature. Powder bed fusion technique was used to melt graphene coated 316 L metal powder layer by layer to prevent agglomeration of graphene inside the matrix. To identify the chemical state of the elements in the prepared composite, synchrotron based X-ray photoelectron spectroscopy was performed. However, no carbide formation was observed inside the matrix and the prepared composite was purely austenitic. The obtained composite with 0.2 wt % graphene has coefficient of thermal expansion (CTE) equal to 19.3 × 10−6 K-1 which is about 6.2% lower than bare 316 L at 1100 °C. The value further decrease after annealing process and this much decrement in CTE can increase the application window of the material to the large extent.

Medicinal plants are well known to have the advantages of high concentration of medicinal ingredients having clinical importance, curative value, small toxic and side effects. Important compounds viz., paclitaxel, camptothecin, and vincristine have been developed from medicinal plants as first-line of clinical drugs, leading to their consistently increasing demand globally. However, the destruction of natural environment due to excessive mining threatened such resources jeopardizing the successful growing of medicinal plants. A group of beneficial arbuscular mycorrhizal (AM) fungi is known to exist in the rhizosphere of medicinal plants, which can establish a reciprocal symbiosis with their roots, namely arbuscular mycorrhizas. These AM fungi are pivotal in the habitat adaptation of medicinal plants. Studies have demonstrated that AM fungi aided in growth promotion and nutrient absorption of medicinal plants, thereby, accelerating the accumulation of medicinal ingredients and aiding resistance against abiotic stresses such as drought, low temperature, and salinity. An AM-like fungus Piriformospora indica is known to be cultured in vitro without roots, later showed analogous effects of AM fungi on medicinal plants. These fungi provide new mechanistic pathways towards the artificial cultivation of medicinal plants loaded with ingredients in huge demand in international market. This review provides an overview of the diversity of AM fungi inhabiting the rhizosphere of medicinal plants, and analyzes the functioning of AM fungi and P. indica, coupled with future lines of research.

In laboratory scale experiment, Cu–ZrO2 nanocomposite was synthesized using a leaf extract of Melia azedarach plant as a capping agent. The nanocomposite seems to be highly selective for the abolition of Cr(VI) from water system. The chemical compositions and morphology of nanocomposite has been inspected using Fourier transform infrared spectrogram (FTIR), X-ray diffractometer (XRD), field emission scanning electron microscope (FESEM), high-resolution transmission electron microscope (HRTEM), thermo-gravimetric analysis (TGA) and electron dispersive X-ray (EDX). The adsorption mechanism ofCu-ZrO2 nanocomposite was extremely dependent onsolutionpH. The maximum adsorption for Cr(VI) was found at 2.0 pH. Approximately, 95% of Cr(VI)has been adsorbed using Cu–ZrO2 nanocomposite. The experimental data precisely follows Langmuir plot (R2 equal to 0.99). This indicates the single layer adsorption of Cr(VI). Kinetics study indicates the chemical nature of adsorption. Thermodynamic study corresponds to feasible, spontaneous, and endothermic adsorption.

Three dimension fire retardant carbon-CNTs hybrid foams for electromagnetic interference (EMI) shielding effectiveness (SE) were fabricated using a polyurethane (PU) template. Phenolic resin with different contents (0.2–2 wt.%) of mutltiwalled carbon nanotubes (MWCNTs) was mixed using a magnetic stirrer for making a homogenous slurry and then PU foam was impregnated in this slurry followed by carbonization at 1000 °C. The foams were characterized for their morphological, structural, mechanical, EMI shielding, and fire-retardant properties. The total EMI shielding effectiveness (SE) of -57.2 dB was achieved for the carbon foam containing 1 wt.% MWCNTs in the frequency range of 8.2–12.4 GHz. Moreover, the addition of MWCNTs into phenolic resin also enhanced the compressive strength (6.5 MPa), thermal stability and fire retardant performance of carbon-CNTs hybrid foams. The multifunctional carbon-CNTs hybrid foams demonstrate that they are outstanding materials with potential applications in EMI shielding and thermal management for defense and aerospace sectors.

Activated bark prepared from Mangifera indica was used for the removal of Cr(VI) from aqueous solution. Activated bark (AB) was characterized by some instrumental techniques such as Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermal analysis (TGA). The effect of different adsorption parameters such as metal ion concentration, adsorbent dosage, contact time, pH, and the temperature was optimized. Langmuir, Freundlich, and Tempkin’s isotherms were studied for the interpretation of experimental data. Langmuir model was found to be best fitted with a maximum adsorption capacity of 78.96 ​mg/g. The kinetic study was described by pseudo-first-order kinetics and Elovich model. Kinetic study indicates that physio-adsorption play major role in Cr(VI) removal from water system. The thermodynamic parameters such as energy change (ΔG°), enthalpy change (ΔH°) and entropy change (ΔS°) were found to be spontaneous, feasible, and endothermic nature.

Mycorrhizas alter root hair profile, but it is not clear whether exogenous phytohormones regulate the mycorrhizal effects on root hair. Studies were carried out in a two-chambered rootbox separated by 37-μm nylon mesh to establish root+hyphae chamber carrying trifoliate orange [Poncirus trifoliata (L.) Raf.] as the test plant inoculated with Diversispora versiformis and hyphae chamber (without roots). Indole butyric acid (IBA), abscisic acid (ABA), and jasmonic acid (JA) (each at 0.1 μM concentration) were weekly applied into hyphae chamber, in total of six times before plant harvest. Mycorrhization strongly stimulated plant growth performance, and exogenous phytohormones, especially IBA, further magnified the mycorrhizal-stimulated growth responses. Three exogenous phytohormones decreased mycorrhizal colonization in taproot and first-order lateral roots, but increased in second- and third-order lateral roots. These phytohormones also increased hyphal length in nylon mesh and soil, irrespective of root+hyphae or hyphae chamber. Mycorrhizal inoculation significantly increased root hair density of different root classes, and exogenous hormones further strengthened the mycorrhizal effect. Average root hair length was stimulated by mycorrhization, but all exogenous phytohormones weakened the mycorrhizal response. Mycorrhization in combination with exogenous phytohormones showed no response on root hair diameter. Our studies, hence, suggested that application of exogenous phytohormones in hyphae chamber strengthened the D. versiformis-induced changes in average root hair density but weakened in average root hair length in trifofliate orange grown in root+hyphae chamber.

Understanding the behavior of mycorrhiza-originated glomalin, either of plant or soil origin, is anticipated to facilitate better opportunities of modulating antioxidants and carbon distribution in plants. In this study, trifoliate orange seedlings with half of roots were colonized by Acaulospora scrobiculata and Funneliformis mosseae in a split-root rootbox. Mycorrhizal inoculation showed a significantly higher plant biomass of trifoliate orange, regardless of mycorrhizal species. Glomalin-related root protein showed a systematic increase in non-mycorrhiza-inoculated chamber under inoculation with A. scrobiculata and F. mosseae than under non-mycorrhizal inoculation. Similar increase was also observed in easily extractable glomalin-related soil protein and total glomalin-related soil protein as a result of F. mosseae colonization only. Mean weight diameter and soil organic carbon were significantly higher under mycorrhization than non-mycorrhization, irrespective of mycorrhized or non-mycorrhized chamber. Mycorrhizal inoculation stimulated an increase in soil protease activity in the mycorrhized chamber, without any distinctive change in the non-mycorrhized chamber. These results, hence, suggested that mycorrhization conferred a systematic increase in glomalin synthesis in roots and soils, collectively, aiding in better aggregate stability and soil carbon sequestration.

Sol-gel autocombustion technique was used to synthesized composites of barium hexaferrites (BaM) and calcium copper titanate (CCTO) with chemical composition Ba1−xCoxFe12−x−yDyxLayO19 (x = 0.0, 0.1, 0.2, 0.3 and y = 0.0, 0.4, 0.5, 0.6) and Ca1-xErxCu3Ti4−yMnyO12 (x = 0.0, 0.1, 0.2, 0.3 and y = 0.0, 0.4, 0.5, 0.6) respectively. The BaM/CCTO composites exhibit a single crystalline phases of both BaM and CCTO, this observation is supported by Raman spectroscopy. Characteristics peaks of both BaM and CCTO were observed at 439 and 592 cm−1; these peaks give a hint on the formation of both BaM and CCTO phase in the composites. Morphology analysis show that the grains of the BaM nanoparticles exhibit uneven distribution with morphology close to hexagonal structure while the CCTO microparticles shows cubic-like grains with homogenous distribution and the stoichiometry of the prepared composites was also observed. Lattice fringes of BaM nanoparticles and CCTO microparticles with sizes of 0.2629 and 0.2613 nm corresponding to (1 1 4) and (2 2 0) hkl planes respectively have been observed. The observed band-gap increases with increase in crystallite size. The coercivity increases as a result of the presence of CCTO phase. BaMCCTO4 composite shows maximum reflection loss (RL) of −27.9 dB (99.83% absorption) at 16.5 GHz and matching thickness of 3 mm with effective absorption (RL 20 dB) bandwidth of 4.2 GHz. Keywords: Permittivity, Permeability, Reflection loss, Shielding effectiveness, Band gap

We have performed the quantitative structure activity relationship (QSAR) study for N-1 and C-3 substituted indole shiff bases to understand the structural features that influence the inhibitory activity toward the cyclooxygenase-2 (COX-2) enzyme. The calculated QSAR results revealed that the drug activity could be modeled by using molecular connectivity indices (0χ, 1χ, 2χ), wiener index (W) and mean wiener index (WA) parameters. The predictive ability of models was cross validated by evaluating the low residual activity, appreciable cross validated r2 values (Rcv2) and leave one out (LOO) technique.