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In this article the Fluorescence resonance energy transfer (FRET) between two important cationic dyes namely Acridine Orange (AO) and Rhodamine B (RhB) in aqueous solution in presence and absence of montmorillonite (MMT) is demonstrated. The energy transfer is also studied in ethanolic solution. Excited state energy migration is occurred from AO to RhB molecules and the extent of energy transfer efficiency linearly increases with increase in RhB concentration in the solution. Interestingly the incorporation of MMT clay significantly increases the energy transfer efficiencies between the dye pair in the solution but the nature of interaction depends on the clay concentrations studied in the present work. The nature of quenching of steady state fluorescence emission of AO in presence of RhB as well as MMT clay in the mixed ensemble is systematically investigated and further confirmed by Time-resolved fluorescence and temperature-dependent steady state fluorescence emission experiments. AO and RhB dye molecules formed ground state complex with MMT clay followed by static quenching. As the clay platelets successfully control the FRET efficiency and it is also well known that MMT clay can host wide diversity of molecular species therefore, the present studies may provide a new insight for the design and the development of FRET-based molecular sensors.

In this communication, we report the comparative and selective interaction of amino acid d-cysteine (d-Cys) with citrate caped gold nanoparticles (Au NPs) in the presence of a fluorescent dye, rhodamine B (RhB), in aqueous solution. Au NPs of size 27.5 nm could almost fully quench the steady-state fluorescence emission of RhB at their optimum concentrations in the mixed solution. The interactions of d-Cys, l-Cys, all other relevant d- and l-amino acids, neurotransmitters, and other relevant biological compounds with the Au NPs/RhB mixed solution have been explored by monitoring the fluorescence recovery efficiencies from the almost fully quenched state of RhB fluorescence via a simple steady-state spectrofluorometric method. The higher fluorescence recovery for the interaction of d-Cys with the Au NPs/RhB mixed system is accompanied by a distinct color change (red-wine to bluish-black) of the assay medium after the reaction compared to that of all other interfering compounds considered in this work. The sensitivity of this fluorometric response lies in a broad linear range of concentrations of d-Cys and the limit of detection (LOD) is found to be 4.2 nM, which is low compared to many other methods available in the literature. The different degrees of interaction of d-Cys and l-Cys with the Au NPs/RhB mixed sample have been further explored by circular dichroism (CD) spectroscopy and Fourier transform infrared (FTIR) spectroscopy. The selective interaction of d-Cys with the proposed Au NPs/RhB mixed system is also found to be correlated with interparticle cross-linking and aggregations of nanoparticles by the analysis of ζ potential and dynamic light scattering (DLS) study, transmission electron microscopy (TEM), atomic force microscopy (AFM), UV-vis absorption spectroscopy etc. The proposed interaction mechanism is further studied with a normal human urine sample to elucidate that the optimized combination of Au NPs and RhB may be realized as an efficient platform for detection of the amino acid d-Cys in a real biosample via a simple fluorometric approach.

Study was done to look for the future neurodevelopmental outcome of the babies with extremely high serum bilirubin level at 1st week of life. Fifty one term and near term babies were enrolled with features of acute bilirubin encephalopathy (ABE), with bilirubin level more than20mg/dl. They were followed up at 3rd and 6th month to observe their neurodevelopment. Neurological outcome was measured with Denver Development Screening Test (DDST-II) and brainstem evoked response audiometry (BERA). The mean peak total serum bilirubin (TSB) was 25.3±2.35(mg/dl). Abnormal developmental was found in 23.5% babies (12 out of 51) and abnormalities were more in the babies whose TSB was beyond 28mg/dl. Abnormal BERA was found among 13.7% babies. TSB value below 25 mg/dl can be considered as safe cut off value for reversibility of bilirubin induced acute brain damage.

An assay method based on fluorometric and colorimetric change was developed for selective sensing of important thiol containing amino acid L-Cysteine (L-Cys) by using gold nanoparticles (Au NPs) and Rhodamine B (RhB) in aqueous environment. This fluorometric assay is basically relies on the competitive binding between RhB and Au NPs via electrostatic interaction as well as strong thiol(-SH)-Au NPs bonding via chemisorption. Citrate stabilized Au NPs (diameter ∼27 nm) was synthesized by soft chemical method and characterized by UV–Vis absorption spectroscopy and Transmission electron microscopic (TEM) techniques. The change in non-radiative energy transfer between RhB and Au NPs are responsible for the observed drastic fluorescence quenching of RhB via FRET process. The recovery of fluorescence from the assay solution of RhB/Au NPs after addition of L-Cys was found linear over the concentration range 0.01 μM–1000 μM with experimental limit of detection (LOD) of 0.01 μM. The selective interaction of L-Cys with the mixed solution of RhB/Au NPs was reflected by the color change from wine to bluish-black of the final solution. The proposed fluorometric assay method accompanied with the observed colorimetric change could successfully differentiate other interfering amino acids including thiol (-SH) containing compounds namely L-Methionine, L-Homocysteine and antioxidant glutathione with the high degree of accuracy. Also the LOD is comparable to the concentration of L-Cys present in the blood plasma. The proposed sensing mechanism is also confirmed with pure human urine sample to detect the response of L-Cys in the urine. Therefore, this fluorometric assay technique for detection of L-Cys has great potential with the diagnostic impact for biomedical interest.

In this paper an iterative, closed-loop light control scheme is proposed and evaluated by a white light emitting diode-based, daylight-responsive luminaire to follow the time-varying pattern of correlated colour temperature and illuminance of a daylight scene. The proposed control scheme functions primarily with the response signals of two RGB colour sensors, viz., a daylight sensor to monitor the daylight scene at the window plane and an internal light sensor to monitor the light scene created by the test white light emitting diode luminaire. The control scheme controls the lumen delivery of individual light emitting diode arrays of the test luminaire by adjusting the duty cycles to follow the instantaneous correlated colour temperature of daylight and at the same time to respond to the variation of window plane illuminance in the reverse pattern. Evaluation is conducted by laboratory testing and in situ testing. The maximum deviations in correlated colour temperature, illuminance and chromaticity from the required values under laboratory testing and in situ testing are found to be [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text], [Formula: see text], [Formula: see text] respectively, which establish the acceptable performance of the proposed iterative light control scheme.

In this study, we investigated the spectroscopic properties of the water-soluble globular protein bovine serum albumin (BSA) while interacting with zinc oxide (ZnO) semiconductor nanoparticles (NPs) in aqueous medium and in a ZnO/BSA layer-by-layer (LbL) self-assembled film fabricated on poly (acrylic acid) (PAA)-coated quartz or a Si substrate via electrostatic interactions. BSA formed a ground state complex due to its interaction with ZnO NPs, which was confirmed by ultraviolet–visible absorption, and steady state and time-resolved fluorescence emission spectroscopic techniques. However, due to its interaction with ZnO, the photophysical properties of BSA depend significantly on the concentration of ZnO NPs in the mixed solution. The quenching of the fluorescence intensity of BSA in the presence of ZnO NPs was due to the interaction between ZnO and BSA, and the formation of their stable ground state complex, as well as energy transfer from the excited BSA to ZnO NPs in the complex nano-bioconjugated species. Multilayer growth of the ZnO/BSA LbL self-assembled film on the quartz substrate was confirmed by monitoring the characteristic absorption band of BSA (280 nm), where the nature of the film growth depends on the number of bilayers deposited on the quartz substrate. BSA formed a well-ordered molecular network-type morphology due to its adsorption onto the surface of the ZnO nanostructure in the backbone of the PAA-coated Si substrate in the LbL film according to atomic force microscopic study. The as-synthesized ZnO NPs were characterized by field emission scanning electron microscopy, X-ray powder diffraction, and dynamic light scattering techniques.

Generation of alternative source of energy is one of the talks of the present decade. In the present work, the focus has been given to produce energy from perovskite-based solar cells. For this purpose, a unique and novel nano-structured perovskite material ethyl ammonium lead chloride (C2H5NH3 +PbCl3 −) was prepared through a novel co-precipitation route using ethyl amine (C2H5NH2) and hydrochloric acid as the starting precursors with aqueous solution of Pb(CH3COO)23H2O. Finally acetic acid was added in the solution, and this solution was allowed to concentrate and cooled down at room temperature. Then the synthesized material was deposited over TiO2 film in order to fabricate the solar cell. Systematic study using XRD, SEM, UV, and photo conversion were conducted to properly analyze the structural, optical, and electrical properties of device. In the presence of light, this perovskite-based solar cell has shown energy conversion efficiency (η) of around 5.2% which is appreciably good. This result has depicted that this material is promising material for fabrication of highly efficient solar cells. This technology can be applied in industrial scale as substitute of the conventional energy in the future.

A microcontroller based electronic dimmer is developed using pulse width modulation technique. This dimmer is controllable by infra-red remote within a distance of 4 m and can be electrically connected between LED module and its driver. The performance of a developed LED dimmer is assessed on basis of variation of the photometric parameters of commercially available warm white and cool white LED luminaire used in indoor lighting applications. Four equally spaced dimming levels are considered to measure luminous efficacy, spectral power distribution, CIE 1931 chromaticity coordinates, CIE 1976 CIELUV color difference, correlated color temperature, general color rendering index and one specific color rendering index for saturated red color sample. Variations of above parameters are found out with reference to the values measured at rated voltage without the developed dimmer. Analysis of experimentally measured data shows that the developed LED dimmer is capable to vary light output of the WLED luminaire within a range of 25–100% without appreciable variation of its photometric and color parameters. The only exception is observed for the luminous efficacy parameter where it shows about 17 and 14.7% reduction for warm white and cool white LED luminaire at 25% dimming level.

In this paper, the performance of a dynamic light controller (DLC) is experimentally evaluated to achieve a dynamic light source consisting of alternative arrays of warm white and cool white light-emitting diodes (LEDs). The DLC is programmed to drive the light source through both step and continuous variations of correlated colour temperature (CCT) and light output. For step variation, the DLC generates pulse width modulation (PWM) signals to drive the LED arrays to achieve 16 desired set points out of four CCTs (2900–5600 K) and four illuminances (100–300 Lux). The measured set points show deviations within acceptable limits. For continuous variation, the DLC is programmed to make the dynamic light source follow a time-varying pattern of CCT and Illuminance. The variations of measured values are mostly within acceptable limits except at lower CCT and illuminance points. The measured duty cycles of the generated PWM signals from the DLC are almost equal to the corresponding calculated values for both the step and continuous variations indicating good performance. The measured deviations are caused by the differences in lumen output at duty cycles

Expectations are used in almost every branch of economics. And alternative theories of expectations have been developed, including the theory of rational expectations (RE) introduced by Robert Lucas (Jr.). The use of RE in macroeconomic models has changed radically many well-developed earlier results and policy prescriptions. The purpose of the present paper is twofold—first, to discuss the various theories of expectations, and secondly, to show how the Phillips curve in macroeconomics dealing with the celebrated trade-off between inflation and unemployment—yield different results, if alternative expectations mechanisms are used. We thus discuss different versions of the Phillips curve—first, its initial version due to Phillips, showing the existence of a permanent trade-off between inflation and unemployment, next the Friedman–Phelps version using static expectations and showing the existence of only temporary, but no permanent trade-off, and finally, the new classical version with rational expectations showing the absence of any trade-off even temporarily. We add that no new result has been proved here; rather, our objective is mainly to help the students to understand these topics clearly—students who might have felt that the discussion of these topics in the standard textbooks is not always up to expectation.

In this paper we report the photophysical and electrical characteristics of our synthesized imidazole derivative namely l-alkyl-2-(arylazo) imidazole (AAI) organized in Langmuir-Blodgett (LB) films towards the development of organic Schottky barrier diode (SBD). Presence of long alkyl chain in the molecule make it suitable for LB technology and may favour aggregations of the molecules in LB films under barrier compression. The interfacial properties of the formation of Langmuir monolayer of AAI at air-water interface have been studied by surface pressure versus area per molecule (π-A) isotherm and compressibility modulus. Hysteresis study of the isotherm confirmed the formation of stable monolayer of AAI molecular assemblies at air-water interface. The aggregation of AAI molecules in LB films is confirmed by Ultraviolet–visible (UV–vis) absorption, fluorescence emission spectroscopy and Atomic force microscopic (AFM) methods. AAI molecules also formed network type morphology in LB films due to their closure association and aggregations or cluster of molecules which were evidenced by AFM technique. The compression induced aggregations of AAI is reflected as broadened nature of monomeric absorption band along with the emergence of a new absorption band at longer wavelength side for LB film deposited at surface pressure of 25 mN/m. The optical absorption bands of AAI and the corresponding transitions between different electronic states have been simulated by density functional theoretical (DFT) analysis and is compared with the experimental results. Nonlinear behaviour of the current-voltage characteristics and various relevant electrical parameters of the LB film device at the interface of metal electrode (gold) satisfy the necessary conditions showing the properties of a Schottky barrier diode.

In this article, a simple dynamic light controller (DLC) is proposed, designed, and fabricated for practical realization of variable correlated color temperature (CCT) but constant light output white light emitting diode (WLED) light source. This WLED light source consists of alternate strings of warm white (WW) and cool white (CW) LEDs. Light control logic of developed DLC is based on Grassman’s color mixing law and hence the range of CCT variation of the test light source lies within the CCT values of the WW and the CW LEDs. A pulse width modulation (PWM) technique is applied to implement the light control logic and embedded in a PIC microcontroller to control the light outputs of two WLED arrays through enhanced PWM mode with dual PWM output. The developed controller is connected with the test light source and controllable by infrared (IR) remote within a distance of 4 m. Thus, the developed DLC is an integrated module consisting of an IR receiver, IR decoder, control signal (PWM) generator, am...

Integration of available daylight with artificial lighting system is indispensable for successful implementation of the concept of green building or sustainable building. In this work a daylight responsive RF light controller is designed and developed for a daylight-integrated artificial lighting system for a typical indoor space of commercial building. Sensor monitors the external daylight level and corresponding response is transmitted to the light controller wirelessly as RF signal. Light control logic is developed and embedded in the light controller to control the light output of lamps depending on the measured daylight level. The developed light controller is also capable to monitor external daylight available at different window orientations and accordingly controls the light output of different lamps groups adjacent to the respective window. The workings of the developed light control logic and the developed RF light controller are experimentally evaluated in the laboratory and results show satisfactory performance of the developed light controller.

Indian leather industry has massive potential for generating employment and achieving high export-oriented growth. However, its economic performance has not been assessed much till date. The present paper attempts to fill in this gap by examining technical efficiency (TE) of individual leather producing firms for some years since the mid-1980’s. Analyzing the industry’s firm-level data through the two conventional tools, viz., data envelopment analysis and stochastic frontier analysis, the paper observes a significant positive association between a firm’s size and its TE, but no such clear relation between a firm’s age and TE. It also finds significant variation in TE across firms in different groups of states as well as under different organizational structures and observes some technological heterogeneity across states. Although, non-availability of panel data does not allow one to assess effects of economic reforms on the performance of the Indian leather firms, the average firm-level TE, however, seems to be on an increasing path, except for downswing in the immediate post-reform years.

This is web based project which mainly deals with GENOMIC COMPRESSION. Here we have used several compression techniques i,e Huffman Compression Techniques, Four base to single base compression techniques..etc for compressing Nucleotide sequence of huge size. There are two phases one is ADNMINISTRATOR and another NORMAL USER. ADMINISTRATOR handles the data and maintains the database. Initially our aim to generate the encoded file for a particular file at runtime and the signature of that particular file are stored in another file to identify that particular file while decoding but due to stored of time we were not able to generate at runtime but rather we store the encoded file along with signature file in the database and while retrieving decoded data from encoded data we use encoded data file along with the signature file.The DNA sequences storing and transmitting them may require a huge amount of space. This web page are help to reduce the space for storing and transmitting data , also introduce one new techniques along with exiting Huffman Technique of compression routine. DNA and RNA sequences can be considered as tests over a four letter alphabet, namely {a,t,g and c}. This new algorithm can approach a compression rate of 2.1 bits /base and even lower. Time complexity of the algorithm O(n). The time complexity of this algorithm is linear and varies linearly with the size of the source file to be compressed. For accuracy purpose we have use mapping techniques in between input file and output file. The greatest advantage of this program is fast execution, small memory occupation and easy implementation.

A series of tricyclohexyl- and triphenylphosphine boranes, carboxyboranes and cyanoboranes were synthesized. These compounds have potent hypolipidemic effects, antineoplastic and antiinflammatory activities in rodents. Furthermore, they demonstrated potent cyctotoxicity against standard human tissue culture lines. The compounds which afforded the best hypolipidemic activity, i.e. greater than 40% reduction of serum cholesterol and triglyceride levels, were diphenyl-(4-methylphenyl)-phosphine borane and triphenylphosphine carboxyborane. Other derivatives demonstrated more potent antineoplastic activity against the Ehrlich ascites carcinoma growth including triphenylphosphine cyanoborane, 2-amino-4-methyl-pyridine cyanoborane and 2-amino-pyridine cyanoborane. Most of the derivatives showed good activity against murine L1210 lymphoid leukemia, Tmolt3 human leukemia, uterine HeLaS cells, and human glioma cell growth. Select compounds were active against colon adenocarcinoma, KB nasopharynx, lung bronchogenic and osteosarcoma cell growth. Tricyclohexyl- and triphenylphosphine boranes and the carboxy derivatives of the latter borane demonstrated good antiinflammatory activity. Beziehungen zwischen lipidsenkenden Eigenschaften und antineoplastischer Aktivitat von Tricyclohexyl- und Triphenylphosphin-boranen, Carboxyboranen, Cyanoboranen und verwandten Verbindungen Tricyclohexyl- und Triphenylphosphinborane, Carboxyborane und Cyanoborane wurden hergestellt Diese Verbindungen sind bei Nagetieren wirksame Lipidsenker mit antineoplastischen und entzundungshemmenden Eigenschaften, die zugleich gegen die ublichen menschlichen Zellkulturen, die als Standards eingesetzt wurden, cytotoxisch wirken. Die Verbindungen mit den besten Lipidsenker-Eigenschaften — Senkung des Serumcholesterols und der Triglyceride um mehr als 40% — waren Diphenyl-(4-methylphenyl)-phosphinboran und Triphenylphosphin-carboxyboran. Starkere antineoplastische Wirkung gegen Ehrlich-Ascites Carcinom zeigten u.a. Triphenylphosphin-cyanoboran, 2-Amino-4-methylpyridin-cyanoboran und 2-Aminopyridin-cyanoboran. Die meisten Derivate waren gut wirksam gegen L1210-lymphoide Leukamie der Maus, uterine HeLaS-Zellen und menschliche Gliomazellen. Ausgewahlte Verbindungen unterdrucken das Zellwachstum des Colon-Adenocarcinoms, des KB Nasopharynx und des Osleosarcoms. Tricyclohexyl- und Triphenylphosphinborane und Carboxyderivate der letztgenannten Verbindungen waren gute Entzundungshemmer.

Mucosal lymphoid changes were observed in cryopreserved rectal tissues obtained from BALB/c mice infected with Shigella dysenteriae 1, immunized with 57-kDa major antigenic outer membrane protein, and infection after immunization.Our data suggested that caspase-3 is downregulated in CD4(+) cells of immunized BALB/c mice following infection with substantial increased expression of interleukin (IL)-2 and interferon (IFN)-gamma, while caspase-1 is upregulated in CD8(+) cells with decreased expression of IL-4 and IL-10. This indicated an involvement of Fas-mediated lytic pathway for selective deletion of CD8(+) cells out of CD3(+) T cells. IL-18 promotes inflammation and induces IFN-gamma and tumor necrosis factor (TNF)-alpha as the expression of IFN-gamma and TNF-alpha cytokines was evident in this study. It is assumed that the role of caspase-1 in inducing the CD4+ T cell activity increased with IL-18 rather than CD8+ suppressor cell activity. Bcl-2 is capable of inhibiting the Fas/Fas-L-mediated cell death for helper cells. Overall, the findings indicate that majority of the apoptotic cells were CD8(+) T cells in the groups of infection following immunization, and there might be a selective deletion of T lymphocytes mediated by caspase-1 via IL-18.

Six cyanoborane adducts of the heteroaromatic amines, 2-amino-, 3-amino-, 4-amino-, 2-amino-4- methyl-, 4-cyano- and 4-ethylpyridines, and four isothiocyanatoborane adducts of the heteroaromatic amines, 3-methyl-, 4-methyl-, 4-ethyl- and 4-amino- pyridines have been prepared. These have been characterized by elemental analyses and by infrared and 1H and 11B NMR spectral study.

In India it is a common experience that that availability of currencies of various denomination do not often match that corresponding demands. This obviously leads to disorder in the management of the currency in the country. Since supply figures are available while those for the demand by the public are not, no idea about the magnitude of discrepancy between the demand for currencies of various denominations and the supply of the same can be made. In this paper we have presented some estimates of the extent of this discrepancy by denomination at the level of banking transactions, based on a survey conducted in the (Greater) Calcutta postal area. The survey methodology developed here is also expected to help the currency management authorities in getting quick estimates of such imbalances in other regions of the country.

Isothiocyanatoborane complexes with triethyl-, di-i-propyl-, tripropyl-, di-i-butyl- and di-n-butyl-amines have been prepared by treating amine hydrochlorides with NaBH3SCN (generated in situ from the NaBH4, iodine and NaSCN) in refluxing monoglyme. The products have been characterized by spectroscopic methods.

The decomposition algorithm for the solution of large-scale linear programmes has been interpreted by Baumol and Fabian (Management Science, September, 1964) as a procedure for decentralized decision by the multi-division company or the multi-sector economy. While commenting on the possibility of decentralization in this context, they maintain that an economy's optimum point will not in general yield a sectoral optimum. The present note demonstrates that this contention is not valid.

Isothiocyanatoborane complexes with triethyl-, di-i-propyl-, tripropyl-, di-i-butyl- and di-n-butyl-amines have been prepared by treating amine hydrochlorides with NaBH3SCN (generated in situ from the NaBH4, iodine and NaSCN) in refluxing monoglyme. The products have been characterized by spectroscopic methods.