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Conjugation of nano and quantum materials with bovine serum albumin (BSA) to study their biological potential
No full textConjugates of gold nanoparticles (AuNPs) and semiconductor quantum dots (CdS/T) have been synthesized with bovine serum albumin (BSA) using wet chemistry. The optical properties of nano and quantum materials and their BSA conjugate have been studied using UV–Visible and Fluorescence spectroscopy. UV–Visible spectrum of pure BSA showed an absorption maximum at 278 nm, which showed blue shift after its conjugation with nano and quantum materials. Increased concentration of AuNPs during conjugation resulted in broadening of BSA peak (278 nm), which can be related to the formation of ground state complex formation, caused by the partial adsorption of BSA on the surface of NPs. However, increased concentrations of BSA resulted in decrease in SPR intensity of gold nanoparticles (528 nm) and absorbance peak of BSA started diminishing. AuNPs acted as quencher for BSA fluorescence intensity, when excited at 280 nm. The binding constant (K) and the number of binding sites (n) between AuNPs and BSA have been found to be 1.97×102 LM−1 and 0.6 respectively. With quantum dots, conjugation resulted in enhancement of fluorescence emission of quantum dots when excited at 300 nm, which might be due to the stabilizing effect of BSA on QDs or due to energy transfer from tryptophan moieties of albumin to quantum dots
Nondestructive grading of black tea based on physical parameters by texture analysis
No full textTexture is an important characteristic used in identification of objects or regions of interest in an image. This paper describes a technique to discriminate between four different grades of made black tea using textural features based on grey tone spatial dependencies. The statistical features were computed from the tea images and wavelet decomposed sub band images. The multi-layer perceptron (MLP) technique has been used for data classification and 82.33% classification accuracy was achieved. Finally, statistical analysis in the form of one way analysis of variance (ANOVA) has been employed as a validation tool to check for grading accuracy
Coupling of chromatographic analyses with pretreatment for the determination of bioactive compounds in Emblica officinalis juice.
No full textA simple and new method for the simultaneous detection and quantification of vitamin C (ascorbic acid), phenolic acids (gallic acid and ellagic acid), hydroxycinnamic acid (chlorogenic acid) and flavonoids (myricetin, quercetin and kaempferol) in Emblica juice is developed. The compounds are separated in 18 minutes by an intangible curved gradient of 0.1% ortho-phosphoric acid in water (v/v) and acetonitrile, as mobile phase A and B, respectively, using Zorbax SB RP C-18 column at a wavelength of 254 nm. The assay was optimized by varying the mobile phase, gradient type, pretreatment method (thermal and non-thermal) and detection wavelength. The method was validated in terms of linearity, precision, detection limits and quantification limits. Good linear response was observed over the range specified for all the analytes, as confirmed by the correlation coefficient which ranged from 0.991 and 0.995. The limit of detection (LOD) and limit of quantification (LOQ) were found to be in the range of 0.129–0.685 μg ml−1 and 0.43–2.883 μg ml−1 respectively. Pulsed electric field (PEF) was used as the non-thermal pretreatment sample technique. HPLC-PDA showed increased levels of phenolic acids, as gallic and ellagic acid, and flavonoid, as quercetin, in PEF treated Emblica juice with respect to the untreated and thermally treated juice samples (p < 0.05). The overall precision values obtained for standards and samples were within the range 0.01–0.2 and 0.15–0.23 respectively. Further, total polyphenolic content and free radical scavenging capacity of the untreated, thermally and PEF treated Emblica juice were corroborated by HPLC
Moving target detection in thermal infrared imagery using spatiotemporal information.
No full textAn efficient target detection algorithm for detecting moving targets in infrared imagery using spatiotemporal information is presented. The output of the spatial processing serves as input to the temporal stage in a layered manner. The spatial information is obtained using joint space–spatial-frequency distribution and Rényi entropy. Temporal information is incorporated using background subtraction. By utilizing both spatial and temporal information, it is observed that the proposed method can achieve both high detection and a low false-alarm rate. The method is validated with experimentally generated data consisting of a variety of moving targets. Experimental results demonstrate a high value of F-measure for the proposed algorithm
Impact of Nonthermal Pulsed Electric Field on Bioactive Compounds and Browning Activity in Emblica officinalis Juice
No full textThe effect of nonthermal pulsed electric field (PEF)
and thermal treatment (90⁰C for 60s) was studied on quality parameters of Emblica officinalis juice for the period of 6 weeks at 4⁰C using monopolar rectangular pulse of 1µs width. The PEF treatment was given using static chamber at 24kV/cm for 500µs. The quality of Emblica officinalis juice was investigated in terms of non enzymatic browning index (NEBI), 5-hydroxymethyl-2-furfural (HMF), total polyphenol content and antioxidant capacity. ⁰Brix, pH and conductivity were evaluated as physical parameters. The aim of the work was to investigate the effect of PEF on the retention of bioactive compounds and retardation of browning activity. The results showed that conventional thermal treatment had led to a significant (p<0.05) decrease of 48.15% in polyphenol content (129.56 mg of GAE L-1), with higher NEBI and HMF formation (p < 0.05) whilst PEF suppressed NEBI and retained higher polyphenol compounds (168.59mg GAE L-1) with limiting the loss to 32.56% along maximum free radical scavenging activity (92.07%). However, pH, ⁰brix and electrical conductivity of treated juice samples remain unaffected. Therefore, PEF can be considered as an effective nonthermal treatment for retaining bioactive compounds along suppressing browning of emblica juice
Thermally Evaporated Poly(Aniline-co-Fluoroaniline) Films for Ammonia Sensing
No full textChemically synthesized poly(aniline-co-fluoroaniline) [poly(An-FAn)] powder were deposited on platinum substrates using thermal evaporation technique [poly(An-FAn)/vac]. These films were characterized using spectroscopic and cyclic voltammetry techniques. Electrical conductivity and molecular weight of copolymer have been measured. Results revealed that the structure of poly(An-FAn) is maintained during thermal evaporation. The response of poly(An-FAn)/vac films in terms of change in resistance with different concentration of ammonia shows its utility as a sensor material. The films show good response for ammonia. The sensing of 50 ppm of ammonia was achieved with response and recovery time of 13 and 80 seconds, respectively
Facile Route for the Synthesis of a Vertically Aligned ZnO–PANI Nanohybrid Film for Polyphenol Sensing
No full textVertically aligned zinc oxide (ZnO) nanorods have been fabricated on a polyaniline (PANI) film template after electrochemical seeding and hydrothermal growth in a nutrient medium at a low temperature of 65 °C. Dense c-oriented [0001], hexagonal-shaped, vertically aligned ZnO nanorods are obtained on the PANI film surface, which is confirmed by X-ray diffraction and scanning electron microscopy studies. The nanohybrid film used as the working electrode has been characterized for sensing catechin polyphenol in different tea varieties through cyclic voltammetry. Principal component analysis shows enhancement in the classification ability of the nanohybrid film for various concentrations of catechin standard and tea infusions
Electrostatic hand pressure knapsack spray system with enhanced performance for small scale farms
No full textElectrostatic force fields have been employed and enhanced in the design of an electrostatic knapsack spray system for increasing the deposition efficiency and reducing the drift of pesticides. The designed induction charge based electrostatic sprayer offers optimum electrode position and electrical conductivity of liquid. The experiments were conducted in ambient conditions for liquid feed rate 340 ml/min at hand pressure of 30 psi. The charge-to-mass ratio was found to be 0.419 mC/kg at 3.25 kV by a spray liquid of conductivity 10.25 mS/cm. There has been 2–3 fold increase of chemical deposition with better uniformity on the target (potted plant)
Optoelectronics behaviour of ZnO nanorods for UV detection
No full textIn this study ZnO nanorods have been synthesized by a chemical precipitation method. The room temperature UV–Vis absorption spectra of the ZnO nanorods indicated two absorption peaks in the UV region, one in the near UV region and the other attributed to the band gap of ZnO. The Photoluminescence spectra of ZnO nanorods show two emission bands, one ultraviolet emission band at 378 nm and the other in the defect related yellow emission band near 550 nm. The stimulated yellow luminescence of ZnO nanorods were affected by the synthesis time and annealing temperature. The same ZnO nanorods were deposited onto the ITO substrate to form a UV photoconductive detector. The ratio of the UV photogenerated current to dark current was as high as nine times under 3 V bias. Hence, these nanorods can be promising materials in the use of UV radiation detection
Novel Design of Detachable Surgical Tool for Robotic Assisted Minimal Invasive Surgery
No full textIn modern surgical operation, a surgeon using a
robotic surgical system which use a manipulator (a
variety of surgical instruments, such as tissue graspers,
needle drivers), Each of these structures perform
functions for the surgeon such as holding or driving a
needle, grasping a blood vessel, cutting or dissecting
tissue, for this hand input devices of the surgeon’s
workstation coupled to the surgical instrument by a
servo mechanism (more especially DC servo motors).
This servo mechanism provides an interfacing between
surgeon’s hand input and manipulator surgical tool.
The surgeon or assistant will mount robotic surgical
instruments having suitable end effectors (grasper
forceps, scissors, needle etc.) to the manipulator, and
will often pass the end effectors through hollow sleeve
for internal surgical site, so as to treat the targeted
tissues while minimizing injury to the adjacent tissue
structures. We are developing surgical tool with
minimally invasive robotic surgical system. To use
those tools in surgery, the mechanism of system needs
to be simple and durable to reduce the cost of robotic
surgery. In this paper, we present mechanism for
minimally invasive surgical robot tools that have
simple structure, easy to manufacture and control.
Through an extensive design process, a compact and
dexterous robotic surgical manipulator as well as the
supporting control hardware is formed