CuxNi1-xO nanostructures and their nanocomposites with reduced graphene oxide: Synthesis,characterization, and photocatalytic applications

NiO nanostructure was synthesized using a simple co-precipitation method and was embedded on reduced graphene oxide surface via ultrasonication. Structural investigations were made through X-ray diffraction (XRD) and functional groups were confirmed by Fourier transform infrared spectroscopy (FTIR). XRD analysis revealed the grain size reduction with doping. Fourier transform infrared spectroscopy confirmed the presence of metal-oxygen bond in pristine and doped NiO nanostructure as well as the presence of carbon containing groups. Scanning electron microscopy (SEM) indicated that the particle size decreased when NiO nanostructure was doped with copper. BET surface area was found to increase almost up to 43 m²/g for Cu doped NiO nanostructure/rGO composite. Current-voltage measurements were performed using two probe method. UV–Visible spectroscopic profiles showed the blue and red shift for Cu doped NiO nanostructure and Cu doped NiO Nanostructure/rGO composite respectively. Rate constant for Cu doped NiO nanostructure/rGO composite found to increase 4.4 times than pristine NiO nanostructure.     

Copper substituted nickel ferrite nanoparticles anchored onto the graphene sheets as electrode materials for supercapacitors fabrication

Nickel ferrites with high theoretical capacitance value as compared to the other metal oxides have been applied as electrode material for energy storage devices i.e. batteries and supercapacitors. High tendency towards aggregation and less specific surface area make the metal oxides poor candidate for electrochemical applications. Therefore, the improvements in the electrochemical properties of nickel ferrites (NiFe₂O₄) are required. Here, we report the synthesis of graphene nano-sheets decorated with spherical copper substituted nickel ferrite nanoparticles for supercapacitors electrode fabrication. The copper substituted and unsubstituted NiFe₂O₄ nanoparticles were prepared via wet chemical co-precipitation route. Reduced graphene oxide (rGO) was prepared via well-known Hummer's method. After structural characterization of both ferrite (Ni_1-xCu_xFe₂O₄) nanoparticles and rGO, the ferrite particles were decorated onto the graphene sheets to obtain Ni_1-xCu_xFe₂O₄@rGO nanocomposites. The confirmation of preparation of these nanocomposites was confirmed by scanning electron microscopy (SEM). The electrochemical measurements of nanoparticles and their nanocomposites (Ni_0.9Cu_0.1Fe₂O₄@rGO) confirmed that the nanocomposites due to highly conductive nature and relatively high surface area showed better capacitive behavior as compared to bare nanoparticles. This enhanced electrochemical energy storage properties of nanocomposites were attributed to the graphene and also supported by electrical (I-V) measurements. The cyclic stability experiments results showed ~65% capacitance retention after 1000 cycles. However this retention was enhanced from 65% to 75% for the copper substituted nanoparticles (Ni_0.9Cu_0.1Fe₂O₄) and 65–85% for graphene based composites. All this data suggest that these nanoparticles and their composites can be utilized for supercapacitors electrodes fabrication.     

Probiotics for cure of Helicobacter pylori infection: A review

Human physiology normally contains pathogenic and non-pathogenic microorganisms in the gastrointestinal flora. Disturbance of these microorganism balance results in the formation of infection. Extensive use of antibiotics for cure of these disturbances like Helicobacter pylori (H. pylori) infection leads to patient discomfort and associated side-effects. There is a need to adopt adjunct or alternative approach in order to minimize such conditions. Probiotics is one of the potential therapies to cure gastrointestinal discomforts especially associated with H. pylori. It competes through non-immune and immune systems. This review article concludes that probiotics are used to eradicate the infection at increased rate, and decreased associated side-effects are caused by triple therapy. A proper evaluation of these probiotics is demanded before their use in future as a commercial product. Furthermore, their effect on immune system requires more research work so that their usage for other chronic disorders can also be considered.     

Influence of different viscosity grade cellulose-based polymers on the development of valsartan controlled release tablets

This work is based on formulating and optimizing controlled release (CR) valsartan (160 mg) tablets using different viscosity grades of the cellulosic polymer. The objective was to develop an effective once-daily drug delivery system of this cardiovascular agent. Central composite design was used for designing the formulations. Polymers used were Methocel® K4M, K15M and K100M. Compatibility of excipients with active was studied through FT-IR. Micromeritic properties were determined and formulations exhibiting appropriate flow characteristics were compressed. Swelling behavior and in vitro buoyancy effect were studied and response surface curves were constructed to optimize the formulation. Multi-point dissolution profiles of valsartan CR tablets at pH 1.2, 4.5 and 6.8 were obtained. Model-dependent and model-independent methods were performed including f2, stability test as per ICH guidelines and ANOVA. FT-IR studies revealed the compatibility of valsartan with all excipients. Formulation K4T9 (containing 25% K4M polymer) was selected to be the best optimized trial, based on physical properties and controlled release profile (23% at 4 h, 82% at 16 h and 100% at 24 h). Results of buoyancy and swelling behavior indicated that HPMC-K4M polymer exhibited excellent floating lag time and swelling indexes. In vitro drug release kinetics showed that formulation K4T9 displayed Korsmeyer–Peppas drug release pattern with r value > 0.99. The manufacturing process of K4T9 was also found to be reproducible with a shelf life period of 41 and 36 months at room temperature and accelerated conditions, respectively. Valsartan CR matrix-based formulation was successfully prepared with Methocel K4M retardant.     

In vitro synergism of antimutagenic and antioxidant activities of Phoenix dactylifera fruit

The availability of total phenolics of date flesh (Pheonix dactylifera) in aqueous and acidified methanol and in vitro synergism of their antimutagenic and antioxidant activities were investigated. The antimutagenic activities of date flesh extracts tested against Salmonella strains TA-98 and TA-100 using Ames bacterial testing were in the range of 36.47 to 79.74% against the standard mutagens potassium dichromate and sodium azide. The antioxidant activities assessed as maximal inhibitory concentrations (IC₅₀) for DPPH radicals and linoleic acid peroxidation inhibition were 812.90 to 2,076.10 μg/mL and 54.43 to 80.89%, respectively. The total phenolic contents of date flesh extracts (35.76 to 114.09mg/g of gallic acid equivalents) were found to be correlated with the biological activities. Use of 0.5 N acidified methanol was efficient for extraction of phenolic compounds with retained antioxidant and antimutagen activities. Dates are a good candidate as a source for development of chemotherapeutic drugs, nutracueticals, and functional food ingredients.     

Lipid Class and Fatty Acid Composition of Psoralia corylifolia Seed

The purified crude lipid of Psoralia corylifolia seeds was subjected to lipid class and fatty acid analysis by thin layer and gas chromatography. The lipid classes identified were triacyl glycerol, free fatty acid, diacyl glycerol, mono acyl glycerol, hydrocarbon-waxester and polar lipid fractions. Most of the fractions were found to contain high level of C_18:1 while C_18:0, C_18:3 and C_20:0 were also found to be present in all the lipid fractions. It has been observed that the diacyl and monoacyl glycerol fractions contain significant amounts of C_14:0 and C_18:0 while the hydrocarbon-waxester fraction was rich in C_22:0. The polar lipids contain high level of C_18:3 and low level of C_18:1 as compared to other lipid fractions. The fatty acid composition of the whole oil was also determined and found to be similar to other fractions. Unidentified long chain fatty acids were also present in significant amounts in all the lipid fractions.     

pH Responsive Abelmoschus esculentus Mucilage and Administration of Methotrexate: In-Vitro Antitumor and In-Vivo Toxicity Evaluation

The rapid progression in biomaterial nanotechnology apprehends the potential of non-toxic and potent polysaccharide delivery modules to overcome oral chemotherapeutic challenges. The present study is aimed to design, fabricate and characterize polysaccharide nanoparticles for methotrexate (MTX) delivery. The nanoparticles (NPs) were prepared by Abelmoschus esculentus mucilage (AEM) and chitosan (CS) by the modified coacervation method, followed by ultra-sonification. The NPs showed much better pharmaceutical properties with a spherical shape and smooth surface of 213.4–254.2 nm with PDI ranging between 0.279–0.485 size with entrapment efficiency varying from 42.08 ± 1.2 to 72.23 ± 2.0. The results revealed NPs to possess positive zeta potential and a low polydispersity index (PDI). The in-vitro drug release showed a sustained release of the drug up to 32 h with pH-dependence. Blank AEM -CS NPs showed no in-vivo toxicity for a time duration of 14 days, accompanied by high cytotoxic effects of optimized MTX loaded NPs against MCF-7 and MD-MBA231 cells by MTT assay. In conclusion, the findings advocated the therapeutic potential of AEM/CS NPs as an efficacious tool, offering a new perspective for pH-responsive routing of anticancer drugs with tumor cells as a target.     

Power Law Velocity Profile in Fully Developed Turbulent Pipe and Channel Flows

The power law velocity profile has been analyzed in terms of the envelope of the friction factor which gives the friction factor log law. The power law index α and prefactor C are shown as the function of the friction Reynolds number, as well as the function of the alternate variable the nondimensional friction velocity. The fully developed turbulent superpipe flow data of McKeon et al. and fully developed channel flow data of Zanoun et al. have been analyzed and the power law index α and prefactor C data have been estimated, first as a function of the friction Reynolds number and second as function of the nondimensional friction velocity. Based on analysis, several correlations have been proposed that have been supported by the data.     

Fusion of remotely sensed data for soil moisture estimation using relevance vector and support vector machines

A data assimilation (DA) methodology that uses two state-of-the-art techniques, relevance vector machines (RVMs) and support vector machines (SVMs), is applied to retrieve surface (0–6 cm) soil moisture content (SMC) and SMC at a depth of 30 cm. RVMs and SVMs are known for their robustness, efficiency and sparseness and provide a statistically sound approach to solve inverse problems and thus to build statistical models. Here, we build a statistical model that produces acceptable estimations of SMC by using inexpensive and readily available data. The study area for this research is the Walnut Creek watershed in Ames, south-central Iowa, USA. The data were obtained from Soil Moisture Experiments 2002 (SMEX02) conducted at Ames, Iowa. The DA methodology combines remotely sensed inputs with field measurements, crop physiological characteristics, soil temperature, soil water-holding capacity and meteorological data to build a two-step model to estimate SMC using both techniques, i.e. RVMs and SVMs. First, the RVM is used to build a model that retrieves surface (0–6 cm) SMC. This information serves as a boundary condition for the second step of this model, which estimates SMC at a depth of 30 cm. An exactly similar routine is followed with an SVM for estimation of surface (0–6 cm) SMC and SMC at a depth of 30 cm. The results from the RVM and SVM models are compared and statistics show that RVMs perform better (root mean square error (RMSE)?= 0.014 m³ m^?3) when compared with SVMs (RMSE?= 0.017 m³ m^?3) with a reduced computational complexity and more suitable real-time implementation. Cross-validation techniques are used to optimize the model. Bootstrapping is used to check over/under-fitting and uncertainty in model estimates. Computations show good agreement with the actual SMC measurements with coefficients of determination (R ²) for RVM equal to 0.92 and for SVM equal to 0.88. Statistics indicate a good model generalization capability with indexes of agreement (IoAs) for RVM equal to 0.97 and for SVM equal to 0.96.     

Genetic effects on dairy calf growth

Objectives were to establish growth patterns for weight and height in dairy calves from birth to 90 d and to estimate appropriate genetic parameters. Measurements were 7943 body weights and 7005 wither heights of 752 calves. Represented over 12 yr were three breeds, 348 dams, and 115 sires; data resulted from designed calf nutrition experiments. Sources of variation considered in various least squares analyses of variance were breed, sire in breed, calf in sire in breed, sex of calf, treatment-year category, and several interactions. Repeatabilities of weights and heights between birth and 90 d were .64 and .88; heritabilities were .22 and .30; genetic and phenotypic correlations were .53 and .73. A regression equation was estimated for each calf. From these 752 equations, heritabilities of initial weight, initial height, and rates of growth in weight and height were .53, .50, .44, and .19. Genetic correlations were .81; -.07; -.05; .26; .14; .84. Selection schemes for these traits in dairy cattle should consider that although weights and heights at birth and thereafter are highly and positively correlated genetically, as are gains, birth measurements and gains to 90 d may be uncorrelated.