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Here, nickel cobalt oxide micro-flowers (NCO-F) have been prepared by the hydrothermal method for their application as electrode material in supercapacitors. The electrochemical performance of the prepared material has been studied in three different aqueous electrolytes (1 M Na2SO4, 1 M KOH, and 1 M Na2SO4 with hydroquinone (Hq) and benzoquinone (Bq) as redox additives). The NCO-F shows maximum specific capacitance in 1 M KOH (470 Fg−1) followed by 1 M Na2SO4 with Hq and Bq additives (173 Fg−1) and 1 M Na2SO4 (101 Fg−1) at the scan rate of 5 mVs−1. However, the higher value of energy density and power density is obtained in 1 M Na2SO4 (35.80 Whkg−1 at 424 Wkg−1). This is because of the higher potential window possessed by NCO-F in 1 M Na2SO4. The results illustrate that the role of the potential window is important which in turn is governed by the type of electrolyte.

Nowadays researchers are much interested in bioceramics for their use as biological implants. Researchers have succeeded to derive few bioceramic materials which show good biological response with living tissues. Few of the bioceramics are zirconia, hexagonal boron nitride and hydroxyapatite. Herein, the effects of zirconia nanoparticles and hexagonal boron nitride nanosheets in hydroxyapatite powder on the structural, mechanical, and biological properties were investigated. In this study, the formation of a potential composite with desired mechanical and biological properties is strongly anticipated. The present study is also proposed to provide further faces to improve osteogenic properties of the scaffolding material without altering the established mechanical and biological properties. Three different compositions in the system [(95-x)HAp-x(ZrO2)-5hBN] (x = 10, 20, 30) were prepared using a simple solid-state reaction technique. In the samples, significant phase was identified for HAp [Calcium Phosphate Hydroxide: Ca5(PO4)3(OH)]. SEM analysis of the composites revealed well-connected and uniform distribution of ZrO2 and HAp nanoparticles on h-BN sheets. The composite samples 65H30Z5B9h (65HAp-30ZrO2-5hBN sintered at 900 °C) and 65H30Z5B1T (65HAp-30ZrO2-5hBN sintered at 1000 °C) showed improved mechanical and tribological behaviors. These samples exhibited excellent mechanical properties like compressive strength, Young's modulus, toughness and density. The obtained values were 2.154 MPa, 0.0182 MPa, 553.82 MJ/m3, 2.29 g/cm3 for 65H30Z5B9h and 3.798 MPa, 0.0832 MPa, 231.59 MJ/m3, 2.31 g/cm3 for 65H30Z5B1T respectively. Cytotoxicity of the composites was studied on Drosophila fly and Mice calvarial osteoblasts cells at five different concentrations. Toxic effect of the composite 65H30Z5B1T on the fly was confirmed by phenotypic observations, trypan blue staining, pupal count, and larval crawling speed. Composite 65H30Z5B1T was found to be toxic in this study, but the composite 65H30Z5B9h was not. Further, cell viability, alkaline phosphates, and mineralization tests confirmed non-toxic property and enhanced osteogenic activities for the composite sample 65H30Z5B9h.

A Chlorella sp. was isolated from a brackish water high-altitude lake of the Northern-Western Himalayas and selected on the basis of its ability to secrete substantial amount of exopolysaccharide (EPS). The purified EPS was estimated to have molecular weight (Mw) of approximately 1.52 × 105 Da with polydispersity of 2.315 and showed amorphous dense morphology. The production of the EPS was maximized to ≅ 460 mg L−1 through nutrient optimisation. The monosaccharide composition of EPS showed the presence of hexose (glucose, galactose mannose), pentose (xylose, arabinose), deoxy (rhamnose), amino (galactosamine) and acid (galacturonic acid and glucuronic) sugars. The one-dimensional proton NMR and FT-IR analysis confirmed the presence of aliphatic groups. The pseudo-plastic rheology and the antioxidant activity of the EPS suggested its suitability for industrial applications. Importantly, the isolated polysaccharide exhibits its potential for easy and single pot biosynthesis of polysaccharide-capped gold-nanoparticles (AuNPs). The polysaccharide-capped AuNPs displayed exceptional stability at extended pH range and high salinity and suggest that this algal EPS can be utilized for its biotechnological application.

Osteoporosis is a major health problem in postmenopausal women globally. This study determined the mechanism through which coelogin stimulates osteoblastogenesis and its osteoprotective and bone regenerating potential. Coelogin effect on primary calvarial osteoblast cells was determined by measuring alkaline phosphatase activity, mineralization, osteoblast survival, and apoptosis and protein expression studies. The osteoprotective effect of coelogin was also evaluated on osteopenic adult female Swiss mice. At autopsy, bones were collected for dynamic and histomorphometry studies. Serum samples were also collected for assessment of serum parameters. Coelogin treatment led to increased osteoblast proliferation, survival, differentiation, and mineralization in osteoblast cells. Coelogin supplementation to Ovx mice promoted new bone formation, prevented Ovx-induced deterioration of bone microarchitecture, and enhanced bone regeneration. In addition, signaling studies revealed that coelogin treatment activates the ER-Erk and Akt-dependent signaling pathways which stimulate the osteoblastogenesis in osteoblast cells.

Post-translational modifications such as phosphorylation, nitrosylation, and pupylation modulate multiple cellular processes in Mycobacterium tuberculosis. While protein methylation at lysine and arginine residues is widespread in eukaryotes, to date only two methylated proteins in Mtb have been identified. Here, we report the identification of methylation at lysine and/or arginine residues in nine mycobacterial proteins. Among the proteins identified, we chose MtrA, an essential response regulator of a two-component signaling system, which gets methylated on multiple lysine and arginine residues to examine the functional consequences of methylation. While methylation of K207 confers a marginal decrease in the DNA-binding ability of MtrA, methylation of R122 or K204 significantly reduces the interaction with the DNA. Overexpression of S-adenosyl homocysteine hydrolase (SahH), an enzyme that modulates the levels of S-adenosyl methionine in mycobacteria decreases the extent of MtrA methylation. Most importantly, we show that decreased MtrA methylation results in transcriptional activation of mtrA and sahH promoters. Collectively, we identify novel methylated proteins, expand the list of modifications in mycobacteria by adding arginine methylation, and show that methylation regulates MtrA activity. We propose that protein methylation could be a more prevalent modification in mycobacterial proteins.

The global population depends on fairly a small number of crops including wheat, rice and maize for food and nutrition, leaving a wealth of genetic resources neglected. Owing to ever increasing demands of the growing world, food production must be increased but research evidences suggests that climate change has adversely affected crop yields, thereby impacting whole agriculture. Exploring the potential reservoir of underutilized crops would provide a highly diversified agricultural production system in sustaining food and nutritional security under climate change. Buckwheat (Fagopyrum sp.) is one such crop representing a broad gene pool harboring diverse genetic resources for future agriculture due to their suitability to marginalized environments. Research advancements suggest that buckwheat has immense potential of commercialization due to presence of essential nutrients and therapeutics. With a balance of bioactive components and nutraceuticals, it has the ability to withstand various environmental stresses to make it a suitable candidate crop for future nutritional security initiatives. Despite such potential, efforts pertaining to genetic improvement, including breeding and molecular techniques are not exemplary. In this review, we present a comprehensive coverage of buckwheat germplasm research done till date along with a tangible perspective of integrating breeding and omics-driven approaches to accelerate higher genetic gains. The implementation of this strategy could enhance the nutritional benefits and adaptation to changing climates for future needs.

Microscale processes are critically important to soil ecology and biogeochemistry yet are difficult to study due to soil’s opacity and complexity. To advance the study of soil processes, we constructed transparent soil microcosms that enable the visualization of microbes via fluorescence microscopy and the non-destructive measurement of microbial activity and carbon uptake in situ via Raman microspectroscopy. We assessed the polymer Nafion and the crystal cryolite as optically transparent soil substrates. We demonstrated that both substrates enable the growth, maintenance, and visualization of microbial cells in three dimensions over time, and are compatible with stable isotope probing using Raman. We applied this system to ascertain that after a dry-down/rewetting cycle, bacteria on and near dead fungal hyphae were more metabolically active than those far from hyphae. These data underscore the impact fungi have facilitating bacterial survival in fluctuating conditions and how these microcosms can yield insights into microscale microbial activities.

Thin films of nickel cobalt oxide-reduced graphene oxide-polyvinyl alcohol (NCO-RGO-PVA) nanocomposite have been prepared for their use as electrode material for flexible supercapacitors. At first graphene oxide, synthesized by modified Hummer’s method, is reduced to reduced graphene oxide (RGO). Then, the nickel cobalt oxide nanoparticles have been prepared by hydrothermal method. Finally films of NCO-RGO-PVA have been prepared by chemical method. As prepared nanocomposite is then characterized structurally by X-ray diffraction (XRD). Also the crystallite size corresponding to prominent plane is calculated and it comes out to be ∼6 nm confirming the formation of nanocomposite. Electrochemical properties are interrogated by cyclic voltammetry and galvanostatic charge-discharge method. The nanocomposite films exhibit the specific capacitance of 127 Fg−1 at the current density of 0.67 Ag−1 and corresponding energy and power density comes out to be 17.6 Whkg−1 and 371 Wkg−1 respectively. The results show that the prepared nanocomposite can be a good electrode material for flexible supercapacitors.

Low-resistance and high quality contacts are necessary for utilizing the electronic applications of Transition Metal Dichalcogenides (TMDs). Earlier reported work on decreasing the contact resistance is mainly based on techniques those results in either oxidation or degradation of samples. So, achieving ohmic junction behavior of metal and semiconducting TMDs is the need of the hour to boost nanoelectronics. In this work, MoS2 thin films are synthesized using modified thermal chemical vapor deposition technique. Indium electrodes are deposited on these films and Indium-MoS2 junction is studied.

The present study deals with the effect of dual cathode buffer layer (CBL) on the performance of bilayer of 4,4′-cyclohexylidenebis[ N , N -bis(4-methylphenyl)benzenamine] (TAPC) and fullerene (C70)-based organic solar cell (OSC) with low donor concentration. OSC devices with CBLs have been fabricated using thermal vapor deposition technique. We report the use of lithium fluoride (LiF) and molybdenum trioxide (MoO 3 ) as CBLs. The insertion of LiF between C70 and aluminium (Al) electrode enhances the power conversion efficiency (PCE) of device from 1.89% to 2.47% but quenching of photogenerated excitons is observed at interface of C70 and LiF layers. Incorporation of MoO 3 between LiF and Al electrode further enhances PCE of device to 3.51%. This has also improved the material quality and device properties, by preventing the formation of gap states and diminishing exciton quenching.

The presence of harmful contaminants in the waste stream is an important concern worldwide. The convergence of biotechnology and nanoscience offers a sustainable alternative in treating contaminated waters. Hexavalent chromium, being carcinogenic deserves effective and sustainable methods for sequestration. Here in, we report the immobilization of a prokaryote (Rhizobium) and eukaryote (Saccharomyces cerevisiae) in multiwalled carbon nanotubes (MWCNTs) for the effective adsorption of hexavalent chromium. The carboxylic groups were introduced into the MWCNTs during oxidation using potassium permanganate and were subjected to EDC-HOBT coupling to bind with microbial cell surface. FTIR, TGA, BET, FESEM-EDAX, HRTEM, XPS and confocal microscopy were the investigative techniques used to characterize the developed biosorbents. Experimental variables such as pH, adsorbent dosage, kinetics, isotherms and thermodynamics were investigated and it was observed that the system follows pseudo second order kinetics with a best fit for Langmuir isotherm. Electrostatic interactions between the functional groups in the microbial cell wall and hydrochromate anion at pH 2.0 propel the adsorption mechanism. The lab scale column studies were performed with higher volumes of the Cr(VI) contaminated water. Sodium hydroxide was used as the desorbing agent for reuse of the biosorbents. The sustainable biosorbents show prospects to treat chromium contaminated water.

We have explored the effect of Cu dopant concentration on the electrical transport properties of Cu doped CdSe thin films at two concentrations of Cu (at 1 and 5 at.%). Structural, morphological and elemental analysis has been carried out by using X-ray Diffraction (XRD), Scanning electron microscopy (SEM) and Energy Dispersive X-ray analysis (EDX). XRD analysis reveals the hexagonal (wurtzite) structure of nc-CdSe:Cu 1% and nc-CdSe:Cu 5% thin films. EDX analysis determines the atomic weight percentage of Cu in these thin films. SEM studies reveal that the grains are uniformly distributed all over the surface of the substrates for nc-CdSe:Cu 1% and nc-CdSe:Cu 5% thin films. Dark conductivity measurements are made on nc-CdSe:Cu 1% and nc-CdSe:Cu 5% thin films in the temperature range 110–370 K in order to determine the effect of Cu concentration. The obtained results reveal that dark conductivity increases as the Cu dopant concentration increases as compared to undoped nc-CdSe thin films. Dark conductivity graphs show two distinct regions at high and low temperatures with decreasing activation energies. Low temperature data is analyzed using Mott’s variable-range hopping model which indicates hopping in localized states near the Fermi level. Various Mott parameters such as the density of localized states N(EF), characteristic temperature (To), hopping distance (R) and hopping energy (W) near the Fermi level are calculated. The concentration of charge carriers and carrier mobility are calculated for nc-CdSe:Cu 1% and nc-CdSe:Cu 5% thin films by using Hall measurements. Constant photocurrent measurement is also performed on Cu 1% and Cu 5% doped CdSe thin films to determine occupied density of states, Urbach parameter and density of defect states. Obtained results show that occupied density of states increases for nc-CdSe:Cu 5% as compared to nc-CdSe:Cu 1% thin films.

Background To evaluate the efficacy of tulsi extract mouthrinse in reducing halitosis as compared to chlorhexidine and hydrogen peroxide mouthrinses using spectrophotometric analysis. Material and methods It was a parallel, single center, double blinded randomized controlled trial of 15 days duration. A total of 300 participants were screened, out of which 45 subjects those fulfilled inclusion criteria of age range 17-35 years were included in the trial. The participants were randomly provided with tulsi, hydrogen peroxide or chlorhexidine mouthwashes (control group) to use 10 ml twice daily for 15 days. Clinical measurements were taken at baseline and 15 days using arbitrary 0-5 scale for organoleptic odor assessments, spectrophotometric analysis for Volatile Sulphide Compounds (VSCs) from saliva samples, Loe & Silness gingival index and Silness & Loe plaque index. Results After intervention, organoleptic, VSCs, gingival and plaque scores showed statistically significant decrease in all the three study groups. The mean percentage reduction in VSC and organoleptic scores was significantly greater in chlorhexidine and hydrogen peroxide groups than in the tulsi group and the mean percentage reduction in plaque and gingival scores was significantly greater in chlorhexidine group than in hydrogen peroxide and tulsi group. Conclusions Tulsi may not have the efficacy of chlorhexidine and hydrogen peroxide mouthrinses. But, Tulsi is effective in reducing halitosis, plaque and gingivitis and with its lack of side effects & cost effectiveness, can be an effective & economic tool to deal with halitosis. The spectrophotometric technique appears to be a promising method for evaluation of oral malodor. Key words:Halitosis, tulsi mouthwash, chlorhexidine, hydrogen peroxide, spectrophotometric analysis.

The Two dimensional (2D) transition metal dichalcogenides material Molybdenum Diselenide (MoSe2) is synthesized by route of hydrothermal method. UV-vis Spectroscopy and X-Ray Diffraction (XRD) confirms that MoSe2 has been synthesized. Further, polymer composites of MoSe2 /Poly (methyl methacrylate) (PMMA) are formed and optical properties of its thin film are studied. MoSe2 nanosheets show the diffraction peak at 2θ=14.04°, 33.52° and 54.38° whereas in MoSe2-PMMA nanocomposite amorphous nature is observed. The Optical Energy band gap of MoSe2 and its composite is calculated to be 1.6eV and 2.75eV respectively. The averaged value of refractive index is found to be 4.94 in case of PMMA-MoSe2 nanocomposite whereas for MoSe2 it was obtained 1.35. There is a rise in extinction coefficient (k) values in case of polymer nanocomposite. Moreover, dielectric constant (ei) showed a direct relation with refractive index (n).

We have prepared nanocomposite films of reduced graphene oxide (rGO) and nickel cobalt oxide quantum dots (NCO-QDs) by chemical method, and these are represented by NCO-rGO. Different nanocomposite films have been formed by varying the ratio of NCO-QDs and rGO. The obtained value of the specific capacitance of the nanocomposite (NCO5-rGO1.5) is 265 F g−1 (260 C g−1) at 0.73 A g−1 which is much higher than rGO alone (96 F g−1 at 0.33 A g−1). As the asymmetric/hybrid configuration also enhances the potential window, so in this work, we have fabricated an asymmetric supercapacitor with NCO5-rGO1.5 as the positive electrode and rGO as a negative electrode using 1 M Na2SO4, neutral aqueous solution, as the electrolyte. The assembled supercapacitor delivered the specific capacitance value of 131 F g−1 (197 C g−1) at an energy density of 47 W h kg−1 and a power density of 631 W kg−1 within a wide potential window of 1.6 V. The potential window of the device can be extended up to 2.4 V, but in that case, its coulombic efficiency decreases. The device retains a specific capacitance of 69% after 1000 cycles of charge-discharge. Also, a solid-state device has been fabricated, which displays a potential of 3.4 V after charging 20 s. All these results may prove fruitful for the design of high energy density supercapacitors in the future.

Binary metal oxides have great potential as electrode materials for supercapacitors. Three-dimensional flower-like nickel-cobalt oxide (NiCo2O4) nanostructures have been obtained by a simple and cost-effective hydrothermal synthesis followed by annealing at distinct temperatures. The effect of calcination temperature, on the structure and the electrochemical behaviour of the nanostructures, has also been investigated. Highly porous, hollow and continuous structures of NiCo2O4 quantum dots (NCO-QDs), formed at the calcination temperature of 300 °C, delivered a specific capacitance of 362 F g−1 at a current density of 0.5 A g−1. The good electrochemical behaviour of these nanostructures may be related to their unique, highly porous, integrated nanostructures that provide a good electroactive surface for faradaic redox reactions to occur. Also, an asymmetric-supercapacitor with NCO-QDs as positive electrode and reduced graphene oxide (rGO) as negative electrode has been fabricated which exhibits a good charge storage capacity (81 F g−1 at the scan rate of 5 mV s−1) along with very good cycling stability (86% capacitance retention after 1000 cycles). The energy density and power density of the supercapacitor have been checked at a potential window of 2.5 V after 1000 charge-discharge cycles. The device has shown a very good energy density of 69.5 W h kg−1 along with high power density of 2.22 kW kg−1 at a current density of 1.5 A g −1. So, this study suggests that the prepared NCO-QDs are prospective candidates for fabricating supercapacitor electrodes with good electrochemical performance in an extended potential window.

To reduce the cost of solar electricity, there is an enormous potential of thin-film photovoltaic technologies. An approach for lowering the manufacturing costs of solar cells is to use organic (polymer) materials that can be processed under less demanding conditions. Organic/polymer solar cells have many intrinsic advantages, such as their light weight, flexibility, and low material and manufacturing costs. But reduced thickness comes at the expense of performance. However, thin photoactive layers are widely used, but light-trapping strategies, due to the embedding of plasmonic metallic nanoparticles have been shown to be beneficial for a better optical absorption in polymer solar cells. This article reviews the different plasmonic effects occurring due to the incorporation of metallic nanoparticles in the polymer solar cell. It is shown that a careful choice of size, concentration and location of plasmonic metallic nanoparticles in the device result in an enhancement of the power conversion efficiencies, when compared to standard organic solar cell devices.Contents of Paper

Nanocrystalline cadmium selenide (nc-CdSe) thin films have been prepared by thermal evaporation using the inert gas condensation (IGC) technique. Transmission electron microscopy (TEM) studies show that the CdSe nanocrystals (NCs) are spherical in shape. Constant photocurrent method (CPM) is used to determine the value of absorption coefficient in low absorption region of as-deposited, annealed and light soaked nc-CdSe thin films. Values of optical band gap ( E g ) have been determined by using Tauc's relation for as-deposited, annealed and light soaked nc-CdSe thin films from the α values evaluated from reflection and transmission measurements. We have used a derivative procedure to sub-gap absorption spectra in order to get information on the energetic distribution of the occupied density of states below Fermi level. Constants such as optical gap E g , Urbach edge E u have been obtained from CPM spectra in as-deposited, annealed and light soaked nc-CdSe thin films. Concentration of defect states has also been calculated in as-deposited, annealed and light soaked nc-CdSe thin films.

Thin films of the undoped nanocrystalline CdSe (nc-CdSe) and doped (Zn and In) thin films have been prepared by physical vapor deposition in the presence of argon as inert gas at room temperature. The influence of the doping materials on the stoichiometry, grain size and trap parameters has been explored by means of Energy Dispersive X-ray Spectroscopy (EDX), Transmission Electron Microscopy (TEM) and thermally stimulated current (TSC) measurements. The TEM results show that small particles of nanometer range are formed in thin films and that size increases slightly with Zn doping and decreases when In is used as the doping material. TSC measurements in the temperature range from 225 to 350 K are performed at different heating rates. Well defined TSC peaks have been observed. The peaks shift to higher temperatures as heating rate is increased. Trap parameters, such as trap depth and density of traps have been determined. The trap parameters have been evaluated by using Gaussian fit and different heating rates methods. Good agreement has been obtained between trap parameters calculated from these two methods. It is observed that the trap depth decreases and trap density increases in doped samples compared to undoped ones.

Thin films of Ag doped CdSe have been prepared by thermal evaporation using inert gas condensation (IGC) method taking Argon as inert gas. The prepared thin films are annealed at 363 K for one hour. The sub-band gap absorption spectra in the as deposited and annealed thin films have been studied using constant photocurrent method (CPM). The absorption coefficient in the sub-band gap region is described by an Urbach tail in both as deposited and annealed thin films. The value of Urbach energy and number density of trap states have been calculated from the absorption coefficient in the sub-band gap region which have been found to increase after annealing treatment indicating increase in disorderness in the lattice. The energy distribution of the occupied density of states below Fermi level has also been studied using derivative procedure of absorption coefficient.

CdTe quantum dots embedded in glass matrix are grown using two-step annealing method. The results for the optical transmission characterization are analysed and compared with the results obtained from CdTe quantum dots grown using conventional single-step annealing method. A theoretical model for the absorption spectra is used to quantitatively estimate the size dispersion in the two cases. In the present work, it is established that the quantum dots grown using two-step annealing method have stronger quantum confinement, reduced size dispersion and higher volume ratio as compared to the single-step annealed samples. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

We report the effects of chemical vapours on the Raman and infrared absorption spectra of α crystalline nickel phthalocyanine thin films. Transmission electron micrograph of the thin films suggests presence of nano-sized particles of nickel phthalocyanine in the thin film. Some vibrational bands show changes in their positions and/or intensities on exposure of thin films with chemical vapours. These changes have been interpreted on the basis of interactions of the vapours molecule with the central nickel ion and other peripheral atoms of the phthalocyanine ring. Density functional theory (DFT) calculations have been carried out to determine the probable geometric structures of the complexes of vapour and phthalocyanine molecules. Calculated geometric structures show in-plane and out-of-plane distortions in the phthalocyanine molecule. Calculations further suggest charge transfer between vapour and phthalocyanine molecules.