WS2 Nanotube-Embedded SiOC Fibermat Electrodes for Sodium-Ion Batteries.

Layered transition metal dichalcogenides (TMDs) such as tungsten disulfide (WS2) are promising materials for a wide range of applications, including charge storage in batteries and supercapacitors. Nevertheless, TMD-based electrodes suffer from bottlenecks such as capacity fading at high current densities, voltage hysteresis during the conversion reaction, and polysulfide dissolution. To tame such adverse phenomena, we fabricate composites with WS2 nanotubes. Herein, we report on the superior electrochemical performance of ceramic composite fibers comprising WS2 nanotubes (WS2NTs) embedded in a chemically robust molecular polymer-derived ceramic matrix of silicon-oxycarbide (SiOC). Such a heterogeneous fiber structure was obtained via electrospinning of WS2NT/preceramic polymer solution followed by pyrolysis at elevated temperatures. The electrode capacity fading in WS2NTs was curbed by the synergistic effect between WS2NT and SiOC. As a result, the composite electrode exhibits high initial capacity of 454 mAh g-1 and the capacity retention approximately 2-3 times higher than that of the neat WS2NT electrode.

Antifungal potential of Azotobacter species and its metabolites against Fusarium verticillioides and biodegradation of fumonisin.

AIMS: In the study, seven Plant Growth Promoting Rhizobacteria (PGPR) Azotobacter species were screened against three strains of Fusarium verticillioides to test its antifungal activity. Azotobacter strains were tested for the degradation of fumonisin produced by F. verticillioides. Secondary metabolites were isolated and characterized from the Azotobacter strains for the first time. METHODS AND RESULTS: Potential seven Azotobacter species antifungal activity was tested following the dual culture assay against three strains of Fusarium verticillioides namely FVM-42, FVM-86 and MTCC156 estimating the substantial zone of inhibition. Azotobacter species AZT-31 and AZT-50 strains significantly inhibited the growth of F. verticillioides recording drastic growth enhancement of maize under in-vitro conditions by calculating the infection incidence, vigour index and germination percentage. As confirmation, dereplication studies were conducted for the reconfirmation of Azotobacter strains by isolating from rhizoplane. Azotobacter strains played a key role in the degradation of fumonisin produced by F. verticillioides reporting 98% degradation at 2 h of incubation with the pathogen. Furthermore, in the study first time, we have tried to isolate and characterize the secondary metabolites from the Azotobacter strains exhibiting six compounds from the species AZT-31 (2) and AZT-50 (4). Preliminary in-vitro experiments were carried out using the compounds extracted to check the reduction of infection incidence (90%) and increase in germination percentage upto 50 to 70% when compared to the test pathogen. CONCLUSION: Azotobacter strains referred as PGPR on influencing the growth of plant by producing certain substances that act as stimulators on inhibiting the growth of the pathogen. SIGNIFICANCE AND IMPACT OF THE STUDY: The future perspective would be the production of an active combination of carboxamide compound and Azotobacter species for preventively controlling the phytopathogenic fungi of plants and crops and also towards the treatment of seeds.

Antifungal Potential of Azotobacter salinestris Strain Azt 31 against Phytopathogenic Fusarium spp. Associated with Cereals.

Antifungal efficacy of Azotobacter salinestris against trichothecene-producing Fusarium spp. was investigated in maize, sorghum, and wheat. The three cereals were subjected to four treatments as control (T1), Fusarium alone (T2), combination of Fusarium and A. salinestris treatment (T3), and only A. salinestris (T4). All the treatments were evaluated for total mass of seedlings, root and shoot length, seed germination, and vigor index (VI), and extent of rhizoplane colonization by A. salinestris was investigated. Further, greenhouse studies were conducted to learn the efficacy of A. salinestris in vivo conditions. Antifungal efficacy was tested by the dual-culture method which resulted in significant reduction in Fusarium growth. Infection by Fusarium was reduced up to 50% in treated cereals such as maize, sorghum, and wheat, and there was also significant increase in seedling mass in the three hosts. Maize showed the highest VI (1859.715), followed by sorghum (1470.84), and wheat (2804.123) with A. salinestris treatment. In addition, seed germination was enhanced to 76% in maize, 69% in sorghum, and 68% in wheat, respectively. Efficacy of rhizoplane colonization showed successful isolation of A. salinestris with high CFU rate, and furthermore, significant colonization inhibition by Fusarium spp. was observed. In the greenhouse conditions, on the 45th day of the experimental set-up, the highest shoot length/root length recorded in maize was 155.70/70.0 cm, in sorghum 165.90/48.0 cm, and in wheat 77.85/56.0 cm, and the maximum root mass recorded was 17.53 g in maize, 4.52 g in sorghum, and 1.90 g in wheat. Our present study showed that seed treatment by A. salinestris, may be used as an alternate biocontrol method against Fusarium infection in maize, sorghum, and wheat.

TiNF and Related Analogues of TiO2 : A Combined Experimental and Theoretical Study.

Aliovalent anion substitution in inorganic materials brings about marked changes in properties, as exemplified by N,F-codoped metal oxides. Recently, complete substitution of oxygen in ZnO by N and F was carried out to generate Zn2 NF. In view of the important properties of TiO2 , we have attempted to prepare TiNF by employing an entirely new procedure involving the reaction of TiN with TiF4 . While the reaction at low temperature (450 °C) yields TiNF in the anatase phase, reaction at a higher temperature (600 °C) yields TiNF in the rutile phase. This is interesting since the anatase phase of TiO2 also transforms to the rutile phase on heating. The lattice parameters of TiNF are close to those of the parent oxide. Partial substitution of oxygen in TiO2 by N and F reduces the band gap, but complete substitution increases the value comparable to that of the oxide. We have examined properties of N,F-codoped TiO2 , and more interestingly N,F-codoped Ti3 O5 , both with lower band gaps than the parent oxides. A detailed first-principles calculations has been carried out on structural and electronic properties of N,F-TiO2 and the TiNF phases. This has enabled us to understand the effects of N,F substitution in TiO2 in terms of the crystal structure, electronic structure and optical properties.

Cd2NF, an analogue of CdO.

Cd2NF, isoelectronic with CdO, has been prepared by ammonolysis of CdF2. Cd2NF has the rock salt structure of CdO and shows electronic properties similar to CdO. First principles calculations shed light on the electronic structure and properties.

Zn2NF and Related Analogues of ZnO.

Substitution of aliovalent N(3-) and F(-) anions in place of O(2-) in ZnO brings about major changes in the electronic structure and properties, the composition, even with 10 atomic percent or less of the two anions, rendering the material yellow colored with a much smaller band gap. We have examined the variation of band gap of ZnO with progressive substitution of N and F and more importantly prepared Zn2NF which is the composition one obtains ultimately upon complete replacement of O(2-) ions. In this article, we present the results of a first complete study of the crystal and electronic structures as well as of properties of a stable metal nitride fluoride, Zn2NF. This material occurs in two crystal forms, tetragonal and orthorhombic, both with a band gap much smaller than that of ZnO. Electronic structures of Zn2NF as well as ZnO0.2N0.5F0.3 investigated by first-principles calculations show that the valence bands of these are dominated by the N (2p) states lying at the top. Interestingly, the latter is a p-type material, a property that has been anticipated for long time. The calculations predict conduction and valence band edges in Zn2NF to be favorable for water splitting. Zn2NF does indeed exhibit good visible-light-induced hydrogen evolution activity unlike ZnO. The present study demonstrates how aliovalent anion substitution can be employed for tuning band gaps of materials.

Antifungal activity of Azotobacter nigricans against trichothecene-producing Fusarium species associated with cereals.

Antifungal efficacy of Azotobacter nigricans on Fusarium infection, total seedlings mass, root and shoot length, and seed germination in maize, sorghum, and wheat were investigated. Antifungal efficacy of A. nigricans against Fusarium sporotrichioides, Fusarium graminearum, Fusarium poae and Fusarium equiseti showed a significant reduction in growth and Fusarium infection incidence (up to 50%) in all the three treated cereals. However, challenge inoculation of Fusarium spp. to the three cereals showed 100% infection incidence. Total mass of the maize seedlings increased two fold by A. nigricans treatment; however, only a slight increase was observed in sorghum and wheat seedlings. The highest vigour index recorded in maize was 1321 against Fusarium crookwellense, 1616.71 against Fusarium sporotrichioides in sorghum, and 1584.8 against Fusarium acuminatum in wheat treated with A. nigricans. Highest germination incidence of 64% was in maize, 67% in sorghum, and 56% in wheat treated with A. nigricans.

Evaluation of cytotoxicity of aqueous extract of Graviola leaves on squamous cell carcinoma cell-25 cell lines by 3-(4,5-dimethylthiazol-2-Yl) -2,5-diphenyltetrazolium bromide assay and determination of percentage of cell inhibition at G2M phase of cell cycle by flow cytometry: An in vitro study.

INTRODUCTION: Malignancies constitute a wide variety of disorders having high mortality and morbidity rates. Current protocols for management include surgical intervention, chemotherapy, and radiation which possess numerous adverse effects. Many phytochemicals are available with anticancer properties similar to anticancer drugs. Major benefit of these compounds is apparent lack of toxicity to normal tissues. Graviola (botanical name: Annona Muricata) contain bioactive compound "annonaceous acetogenins" known for anticancer activity on cancer cell lines. AIMS: To determine cytotoxicity of Graviola and percentage cell inhibition at G2M phase of cell cycle. SETTINGS AND DESIGN: The cytotoxicity of aqueous extract of Graviola leaves on squamous cell carcinoma (SCC-25) cell lines at various concentrations evaluated using 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The percentage of SCC-25 cell inhibition at G2M phase of cell cycle determined using flow cytometry. METHODS: Graviola Leaves, American Type Culture Collection SCC-25 cell lines were procured from Skanda Laboratories, Bengaluru. The cytotoxicity of aqueous extract of Graviola on SCC-25 cells at various concentrations evaluated using MTT assay. The percentage of SCC-25 cell inhibition at G2M phase of cell cycle determined using flow cytometry. STATISTICAL ANALYSIS: Statistical analysis was done using one-way ANOVA. RESULTS: MTT assay showed statistically significant (P < 0.001) dose-dependent inhibition of SCC-25 cell lines by Graviola with IC50 value of 12.42 µg/ml. Flow cytometry revealed that Graviola at 25 and 50 g/ml arrested 53.39% and 52.09% cells in G2M phase of cell cycle respectively, which was statistically significant. CONCLUSION: Graviola showed significant cytotoxic activity and percentage of cell inhibition at G2M phase cell cycle against SCC-25 cell lines.

Analysis of enamel rod end patterns on tooth surface for personal identification--ameloglyphics.

Ameloglyphics is the study of enamel rod end patterns on a tooth surface. Our aim was to study the in vivo analysis of enamel rod end patterns on tooth surfaces for personal identification. In this study, the maxillary left canine and 1st premolar of 30 men and 30 women were included. The cellulose acetate peel technique was used to record enamel rod endings on tooth surfaces. Photomicrographs of the acetate peel imprint were subjected to VeriFinger Standard SDK v5.0 software for obtaining enamel rod end patterns. All 120 enamel rod end patterns were subjected to visual analysis and biometric analysis. Biometric analysis revealed that the enamel rod end pattern is unique for each tooth in an individual. It shows both intra- and interindividual variation. Enamel rod end patterns were unique between the male and female subjects. Visual analysis showed that wavy branched subpattern was the predominant subpattern observed among examined teeth. Hence, ameloglyphics is a reliable technique for personal identification.