A Rapid Colour Test for the Detection of Karanja (Pongamia glabra) Oil in other Vegetable Oils

A rapid colour test was development to detect adulteration or contamination of edible or non-edible vegetable oils with karanja (Pongamia glabra) oil either raw or refined with alkali, acid, alcohol or alcohol-alkali and bleached. The test is based on the development of an intense orange to bright red colour on contacting the oil with phosphoric acid. The detection limit is 1%.     

Formulation and in vitro studies of a fixed-dose combination of a bilayer matrix tablet containing metformin HCl as sustained release and glipizide as immediate release

The emerging new fixed dose combination of metformin hydrocholride (HCl) as sustained release and glipizide as immediate release were formulated as a bilayer matrix tablet using hydroxy propyl methyl cellulose (HPMC) as the matrix-forming polymer, and the tablets were evaluated via in vitro studies. Three different grades of HPMC (HPMC K 4M, HPMC K 15M, and HPMC K 100M) were used. All tablet formulations yielded quality matrix preparations with satisfactory tableting properties. In vitro release studies were carried out at a phosphate buffer of pH 6.8 with 0.75% sodium lauryl sulphate w/v using the apparatus I (basket) as described in the United States Pharmacopeia (2000). The release kinetics of metformin were evaluated using the regression coefficient analysis. There was no significant difference in drug release for different viscosity grade of HPMC with the same concentration. Tablet thus formulated provided sustained release of metformin HCl over a period of 8 hours and glipizide as immediate release.     

Green synthesis of highly stabilized nanocrystalline silver particles by a non-pathogenic and agriculturally important fungus T. asperellum

A controlled and up-scalable biosynthetic route to nanocrystalline silver particles with well-defined morphology using cell-free aqueous filtrate of a non-pathogenic and commercially viable biocontrol agent Trichoderma asperellum is being reported for the first time. A transparent solution of the cell-free filtrate of Trichoderma asperellum containing 1?mM AgNO(3) turns progressively dark brown within 5?d of incubation at 25?°C. The kinetics of the reaction was studied using UV-vis spectroscopy. An intense surface plasmon resonance band at ～410?nm in the UV-vis spectrum clearly reveals the formation of silver nanoparticles. The size of the silver particles using TEM and XRD studies is found to be in the range 13-18?nm. These nanoparticles are found to be highly stable and even after prolonged storage for over 6 months they do not show significant aggregation. A plausible mechanism behind the formation of silver nanoparticles and their stabilization via capping has been investigated using FTIR and surface-enhanced resonance Raman spectroscopy.     

Preconcentration, separation, and indirect detection of nonfluorescent analytes using fluorescent mobility markers

We present a method to achieve separation and indirect detection of nonfluorescent species using fluorescent mobility markers. This technique leverages isotachophoresis (ITP) for both preconcentration and separation. We employ a leading electrolyte (LE), trailing electrolyte (TE), and a set of fluorescent markers of mobilities designed to bound those of nonfluorescent analytes of interest. Fluorescent markers and nonfluorescent analytes are initially mixed homogenously and ITP is initiated. The dynamics of isotachophoresis cause the analyte and fluorescent marker mixture to segregate into respective zones between the LE and TE in the order of reducing mobility. Unlabeled analytes are detected as gaps (regions with local minimums in intensity) in the fluorescent signals of mobility markers. We have successfully demonstrated preconcentration, separation, and detection of unlabeled amino acids serine, glycine, and phenylalanine; and of acetic acid, aspartic acid, and 3-phenylpropionic acid. We show detection of 12 microM concentration of analytes with signal-to-noise ratio of 4.0 and with a high degree of repeatability. We discuss methods for encoding mobility marker identity using marker fluorescence intensity level and alternating fluorescence emission wavelengths. We present example experimental results of fluorescence intensity level encoding.     

Coal–oil–water multiphase fuel: Rheological behavior and prediction of optimum particle size

As the coal–oil–water slurry is gaining importance in place of fuel oil, a better understanding of handling characteristics is in demand. Therefore, experimental investigations have been carried out to investigate the rheological properties of coal–oil–water suspension containing coal particles of different sizes. Different coal stocks with average particle sizes of 108 μm, 75.7 μm and 62.9 μm have been used. The concentration of solid for the experiment varies from 10% to 50% by weight. All experiments have been carried out in a cup and bob type coaxial cylindrical viscometer. Newtonian, shear thinning and shear thickening behavior of suspension has been observed depending on component content and operating conditions. Study with different particle sizes shows that it is possible to achieve an optimum particle size for better handling of such suspension. A generalized correlation has been developed to predict the apparent viscosity of coal–oil–water suspension incorporating the coal concentration, oil concentration, torque and particle diameter. The experimental data are in well agreement with proposed correlation.     

Switch-peptides: design and characterization of controllable super-amyloid-forming host-guest peptides as tools for identifying anti-amyloid agents

Several amyloid-forming proteins are characterized by the presence of hydrophobic and highly amyloidogenic core sequences that play critical roles in the initiation and progression of amyloid fibril formation. Therefore targeting these sequences represents a viable strategy for identifying candidate molecules that could interfere with amyloid formation and toxicity of the parent proteins. However, the highly amyloidogenic and insoluble nature of these sequences has hampered efforts to develop high-throughput fibrillization assays. Here we describe the design and characterization of host-guest switch peptides that can be used for in vitro mechanistic and screening studies that are aimed at discovering aggregation inhibitors that target highly amyloidogenic sequences. These model systems are based on a host-guest system where the amyloidogenic sequence (guest peptide) is flanked by two beta-sheet-promoting (Leu-Ser)(n) oligomers as host sequences. Two host-guest peptides were prepared by using the hydrophobic core of Abeta comprising residues 14-24 (HQKLVFFAEDV) as the guest peptide with switch elements inserted within (peptide 1) or at the N and C termini of the guest peptide (peptide 2). Both model peptides can be triggered to undergo rapid self-assembly and amyloid formation in a highly controllable manner and their fibrillization kinetics is tuneable by manipulating solution conditions (for example, peptide concentration and pH). The fibrillization of both peptides reproduces many features of the full-length Abeta peptides and can be inhibited by known inhibitors of Abeta fibril formation. Our results suggest that this approach can be extended to other amyloid proteins and should facilitate the discovery of small-molecule aggregation inhibitors and the development of more efficacious anti-amyloid agents to treat and/or reverse the pathogenesis of neurodegenerative and systemic amyloid diseases.     

Design of sharp-rejection, compact, wideband bandstop filters

A general procedure is described to design a sharp-rejection wideband bandstop filter by using interference of the signals propagating through two parallel transmission line segments having different electrical lengths and characteristic impedances. Bandwidth and rejection level of the filters can be controlled by changing the impedances of the lines. A simple transmission line model is used for filter analysis. Design graphs are presented. Theoretical prediction is verified by fabricating two filters in microstrip technology. Good agreements is obtained among theoretical prediction, full-wave simulation and measurements.     

A 1-bit full adder using CNFET based dual chirality high speed domino logic

CNFET devices are preferred over CMOS devices for designing high-speed digital circuits. This paper introduces a new technique Dual Chirality High-speed Domino Logic (DCHSDL) for implementing low power and high-speed domino circuits in CNFET technology. Simulations are carried out for 32 nm Stanford CNFET model in HSPICE for 2, 4, 8 and 16 input domino OR gates at a clock frequency of 200 MHz on a DC supply voltage of 0.9 V. The proposed domino technique shows maximum power reduction of 82.55% and maximum delay reduction of 57.97% compared to CPVT technique in CNFET technology at a frequency of 200 MHz. The proposed circuit shows maximum power reduction of 97.90% compared to its analogous circuit in CMOS technology for a 2-input domino OR gate. The proposed technique shows maximum improvement of 1.05× to 1.63× in unity noise gain (UNG) compared to various existing techniques in CNFET technology at a frequency of 200 MHz. The 1-bit Full Adder designed using the proposed technique shows a power reduction of 16.91% and a delay reduction of 23.64% compared to standard FDL 1-bit Full Adder.     

Microstrip bandpass filter design using split‐path method and optimized curvature corrections

Bandpass filters with wide pass‐band are an essential requirement in various equipments of satellite and defence communication sectors. Here a method of split‐path interactions is proposed to approximately predict the resonant frequency and topology of bandpass filters which otherwise fall under the category of heuristic designs. Curved transmission lines are often required to make filter structures physically compact; however, curvature effects create errors in the theoretical (design) prediction of resonant or central frequencies for bandpass filter design. Earlier propositions on curvature corrections had been considerably precise, but recent design standards demand even higher accuracies. The prime feature of this work is the use of a meta‐heuristic optimization (i.e. Particle Swarm Optimization) technique in curvature corrections for the first time which brings accuracies of over 99% in the corrected results. The split paths used in this design are suitably curved, with the proposed optimized curvature correction technique, so as to attain a compact size of the filter. The resulting filter has a low insertion loss of around −1.00 dB and a sharp stopband cut‐off. Fabrication was done on a FR4 microstrip substrate with a good agreement between measured and simulated results. Copyright © 2015 John Wiley & Sons, Ltd.