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Au-Cu alloy nanoparticles were synthesized by a chemical reduction method. Five samples having different compositions of Au and Cu (Au-Cu 3 : 1, Au-Cu 2 : 1, Au-Cu 1 : 1, Au-Cu 1 : 2, and Au-Cu 1 : 3) were prepared. The newly synthesized nanoparticles were characterized by electronic absorption, fluorescence, and X-ray diffraction spectroscopy (XRD). These alloy nanoparticles were also analyzed by SEM and TEM. The particle size was determined by SEM and TEM and calculated by Debye Scherrer’s equation as well. The results revealed that the average diameter of nanoparticles gets lowered from 80 to 65 nm as the amount of Cu is increased in alloy nanoparticles. Some physical properties were found to change with change in molar composition of Au and Cu. Most of the properties showed optimum values for Au-Cu alloy nanoparticles of 1 : 3. Cu in Au-Cu alloy caused decrease in the intensity of the emission peak and acted as a quencher. The fluorescence data was utilized for the evaluation of number of binding sites, total number of atoms in alloy nanoparticle, binding constant, and free energy of binding while morphology was deduced from SEM and TEM.

Abstract Background Prunella vulgaris is medicinally important plant containing high-valued chemical metabolites like Prunellin which belong to family Lamiaceae and it is also known as self-heal. In this research, calli culture were exposed to differential ratios of gold (Au) and silver (Ag) nanoparticles (1:1, 1:2, 1:3, 2:1 and 3:1) along with naphthalene acetic acid (2.0 mg NAA) to investigate its antimicrobial potential. A well diffusion method was used for antimicrobial properties. Results Here, two concentrations (1 and 2 mg/6 µl) of all treated calli cultures and wild plants were used against Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, Bacillus atrophaeus, Bacillus subtilis, Agrobacterium tumefaciens, Erwinia caratovora and Candida albicans. Dimethyl sulfoxide (DMSO) and antibiotics were used as negative and positive controls. Here, the calli exposed to gold (Au) nanoparticles (NPs) and 2.0 mg naphthalene acetic acid (NAA) displayed the highest activity (25.7 mm) against Salmonella typhi than other extracts, which was considered the most susceptible species, while Agrobacterium tumefaciens and Candida albicans was the most resistance species. A possible mechanism of calli induced nanoparticles was also investigated for cytoplasmic leakage. Conclusion From the above data it is concluded that Prunella vulgaris is medicinally important plant for the development of anti-microbial drugs using nanotechnology and applicable in various pharmaceutical research.

This paper proposes some iterative constructions of fixed points for showing the existence and uniqueness of solutions for functional equations and fractional differential equations (FDEs) in the framework of CAT (0) spaces. Our new approach is based on the M∗-iterative scheme and the class of mappings with the KSC condition. We first obtain some ∆ and strong convergence theorems using M∗-iterative scheme. Using one of our main results, we solve a FDE from a broad class of fractional calculus. Eventually, we support our main results with a numerical example. A comparative numerical experiment shows that the M∗-iterative scheme produces high accurate numerical results corresponding to the other schemes in the literature. Our results are new and generalize several comparable results in fixed point theory and applications.

A new highly selective and sensitive electrochemical sensor has been developed, whereby working electrode is modified with bimetallic Au-Pt alloy nanoparticles (NPs). Au-Pt alloy NPs were prepared by a facile method using non/less toxic chemicals. The optical properties of the synthesized NPs were studied by UV-Visible spectroscopy. The surface structure was characterized by X-ray diffraction and scanning electron microscopy. The NPs were found spherical with an average diameter of 14.6 nm. The electrochemical response of modified electrode with polypyrrole and Au-Pt alloy NPs toward the detection of rabeprazole (antiulcer drug) was systematically investigated though cyclic, square wave and differential pulse voltammetry methods. Under optimized conditions, the developed sensor showed its promise for the trace level (1.29 µM) detection of the analyte. Moreover, the designed sensor demonstrated excellent reproducibility and maintained its integrity in a wide pH range and different supporting electrolytes for the sensing of rabeprazole. The Au-Pt alloy NPs based electrochemical sensor exhibited good selectivity, high sensitivity and stability, fast response time, ease of use and reproducibility. [ABSTRACT FROM AUTHOR]

An experiment was conducted to study the effect of different herbicides and row spacings on the growth and yield of tomato at Horticulture Research Farm of Khyber Pakhtunkhwa Agricultural University, Peshawar during 2007. The experiment was laid out in randomized complete block (RCB) design with split plot arrangements having three replications. The herbicides trifluralin @ 2L, s-metolachlor @ 2L and pendimethalin @ 2L ha-1were applied to the main plots, while row spacings of 40, 60, 80, and 100 cm were kept in the subplots. Seedlings of tomato 'Shimla' were transplanted in 3 × 2 m2 plots. The herbicides significantly affected all the parameters of the crop. The highest seedling survival (83%), weed density (240 m-2), weed biomass (10820 kg ha-1), plant height (80 cm) and least days to first flowering (54.7), first fruit set (62.8) and first picking (73.1) were recorded in weedy check plots. While maximum number of branches (3.4) and fruit yield (9.8 t ha-1) were recorded in Treflan 48 EC treated plots. Significantly minimum weed density (92.8 m-2), weed biomass (7153 kg ha-1), maximum plant height (78.6 cm) and maximum fruit yield (9.9 t ha-1) were recorded in 40 cm row spacing, whereas number of branches (3.6) was the highest in 100 cm spacing. The effect of interaction between the herbicides and row spacings was also found significant. Lowest weed density (43 m-2) and weed biomass (4933 kg ha-1) were recorded at 40 cm row spacing treated with Treflan 48 EC. In conclusion, Treflan 48 EC performed best at all the row spacings as compared to other herbicides especially at 40 cm row spacing. [ABSTRACT FROM AUTHOR]

The present work aimed to highlight an efficient, readily accessible, and cost-effective adsorbent derived from Dalbergia sissoo (DS) leaf powder for removing the environmentally hazardous dye “alizarin red S” (ARS) from hydrous medium. A variant of the adsorbent is activated via sulfuric acid and composited with magnetic iron oxide nanoparticles (DSMNC). Both adsorbents are thoroughly characterized using techniques such as Fourier transform infrared spectroscopy, point of zero charge, energy-dispersive X-ray spectroscopy, and scanning electron microscopy, which show that they have a porous structure rich in active sites. Different adsorption conditions are optimized with the maximum removal efficiency of 76.63% for DS and 97.89% for DSMNC. The study was highlighted via the application of various adsorption isotherms, including Freundlich, Langmuir, Temkin, and Dubinin–Radushkevich, to adsorption data. Pseudo-first-order, pseudo-second-order, and intra-particle diffusion models were utilized to investigate the kinetics and mechanism of adsorption. The Freundlich model and pseudo-second-order kinetics exhibited the best fit, suggesting a combination of physical interactions, as confirmed by the D–R and Temkin models. The dominant adsorbate–adsorbent interactive interactions responsible for ARS removal were hydrogen bonding, dispersion forces, and noncovalent aromatic ring adsorbent pi-interactions. Thermodynamic parameters extracted from adsorption data indicated that the removal of the mutagenic dye “ARS” was exothermic and spontaneous on both DS and DSMNC, with DSMNC exhibiting higher removal efficiency.

Lichen planus is an autoimmune disease that typically involves skin and the mucosa of the mouth and genitalia. The involvement of conjunctival and laryngeal is rare. A young patient presented with hoarseness of voice, oral ulcerative lesions and symblephron. Mucosal biopsies (buccal mucosa and supraglottic area) revealed the diagnosis of lichen planus and he was managed accordingly. Although oral lichen planus is frequently reported but simultaneous involvement of oral, ocular and laryngeal mucosa has not been reported earlier.