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41.
Sunita D. Bansod Manisha Bawaskar Sudhir Shende Aniket Gade Mahendra Rai 《IET nanobiotechnology / IET》2019,13(6):609
Here, a rapid and easy transformation by electroporation technique for gene transfer in plants using cell penetrating amino nanocomplex (nanoplex) has been demonstrated in Nicotiana. Nanoplex was prepared using cell penetrating amino acids (CPAs) such as poly‐L‐lysine (PLL) and Argenine (Arg), in combination with the gold nanoparticles (AuNPs). PLLs‐modified nanoplex with zeta potential of 34.2 ± 1.22 mV charge showed 63.3% efficiency for gene transformation in plant cells as compared to 60% when modified with Arg and the zeta potential was found to be 30.0 ± 0.83 mV; whereas, the transformation efficiency without nanoplex was found to be 6.6%. The findings indicate that the zeta potential of positively charged nanocomplex (AuNPs/CPAs/DNA/CPAs) increases the transformation efficiency because of their ability to protect the DNA from electroporation wave and endogenous enzyme damage. Transformation was confirmed by GUS assay and amplification of npt gene. This technique may open up new possibilities of gene transfer in plants, which will enable to produce large number of transgenic plants.Inspec keywords: biochemistry, electrokinetic effects, DNA, biomedical materials, nanomedicine, nanoparticles, gold, cellular biophysics, enzymes, genetics, molecular biophysics, genomicsOther keywords: nanoplex‐mediated plant transformation approach, electroporation technique, gene transfer, cell penetrating amino nanocomplex, cell penetrating amino acids, poly‐L‐lysine, Arg, gold nanoparticles, PLLs‐modified nanoplex, zeta potential, gene transformation, plant cells, transformation efficiency, positively charged nanocomplex, electroporation wave, npt gene, transgenic plants, AuNPs‐CPAs‐DNA‐CPAs, voltage 32.980000000000004 mV to 35.42 mV, voltage 29.169999999999998 mV to 30.830000000000002 mV, Au 相似文献
42.
Although laser-induced incandescence (LII) has been successfully used for soot volume fraction and particle size measurements, uncertainties remain regarding issues of soot vaporization leading to mass loss and morphological changes occurring in soot due to intense heating. Prompt LII detection schemes are often based on the assumption that the associated time scale is shorter than the time scale of soot vaporization or sublimation. The validity of such assumptions is the focus of the current study. Time-resolved light-scattering measurements were made in combination with LII measurements to quantify soot particle vaporization effects resulting from the LII laser pulse. The light-scattering measurements revealed a sharp decrease in total soot particle mass during the time course of the 25 ns full-width LII laser pulse for fluences in the range of 0.5 J/cm2. Light-scattering theory was used to invert the scattering data, revealing approximately 80%-90% reductions in the soot particle volume for LII fluences of 0.47 and 0.61 J/cm2. In addition, the time-resolved scattering measurements show that the time scale of soot vaporization is completely confined to the LII laser pulse itself. Light scattering revealed no soot vaporization only for fluences of approximately 0.1 J/cm2, which is consistent with recent work on low-fluence LII. Possible mechanisms for soot vaporization are discussed, notably for near-threshold fluences. 相似文献
43.
N.A. Romero C. Glinsvad A.H. Larsen J. Enkovaara S. Shende V.A. Morozov J.J. Mortensen 《Concurrency and Computation》2015,27(1):69-93
Density function theory (DFT) is the most widely employed electronic structure method because of its favorable scaling with system size and accuracy for a broad range of molecular and condensed‐phase systems. The advent of massively parallel supercomputers has enhanced the scientific community's ability to study larger system sizes. Ground‐state DFT calculations on ∼ 103 valence electrons using traditional algorithms can be routinely performed on present‐day supercomputers. The performance characteristics of these massively parallel DFT codes on > 104 computer cores are not well understood. The GPAW code was ported an optimized for the Blue Gene/P architecture. We present our algorithmic parallelization strategy and interpret the results for a number of benchmark test cases.Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
44.
Diwakar Gupta John A. Buzacott 《International Journal of Flexible Manufacturing Systems》1996,8(3):233-245
After more than a decade of research on measurement of manufacturing flexibility, it is now recognized that measures of flexibility are, by their very nature, user- and/or situation-specific. In such an environment, a set of principles that could be used by practitioners to test the goodness of metrics which they devise (to suit the requirements of their particular application) will be most useful. This article fulfills the above stated need by developing such a test. This test is then applied to some flexibility measures suggested in recent studies, and their strengths and/or weaknesses are pointed out. 相似文献
45.
The catalytic activity of transition metals in coal liquefaction was studied and compared. Impregnation of coal with transition metals significantly increased oil production and asphaltene and preasphaltene conversion in coal liquefaction. Overall, coal conversion increased marginally and hydrocarbon gas production decreased slightly with metals. Iron impregnation was more active than cobalt, nickel, and molybdenum in preasphaltene conversion, whereas the other metals were more active than iron in asphaltene conversion. Hydrogen consumption decreased with all metals. The quality of generated solvent decreased with iron, but increased with other metals. Significant benefits were observed by using iron and molybdenum together; simultaneous impregnation of coal with iron and molybdenum significantly increased coal, asphaltene, and preasphaltene conversion, as well as oil production compared to individual metals. In addition, a mixture of iron and molybdenum decreased hydrocarbon gas production and increased hydrogen consumption and the quality of generated solvent over iron alone. 相似文献
46.
We study the problem of placing erasure nodes among passive stations in a slotted dual bus network. Erasure nodes are known to improve throughput by allowing slot reuse. It is also known that choices made in locating erasure nodes significantly impact network congestion and overall throughput-especially when traffic patterns exhibit a high degree of locality. We present algorithms to determine optimal placements of erasure nodes that improve upon prior work on this problem: we present simpler and faster polynomial-time algorithms and also consider various useful cost measures. These algorithms can be used to solve related placement problems in which limits on congestion and existing placements are given as input, and the goal is to find the minimum number of erasure nodes required to meet the congestion bound 相似文献
47.
Bhushan Mehendale Rajesh Shende Senthil Subramanian Paul Redner Deepak Kapoor 《Journal of Energetic Materials》2013,31(4):341-360
Ordered mesoporous Fe2O3 was synthesized using cetyltrimethylammonium chloride (CTAC) and polyethylene glycol octadecyl ether (Brij 76) surfactant templates. The gel time was monitored as a function of the concentration ratio of precursor to the surfactant. As-prepared FeOOH gels were extracted in ethanol to remove the surfactant and calcined at 200–400°C for 6 h so that α-Fe2O3 is produced. The FTIR spectra of these gels reveal complete removal of surfactant and water impurities and the presence of Fe-O vibrations. TEM images show ordering of mesopores in the gels prepared using surfactant templating and no ordering of the pores in the gels prepared without surfactant. The gels after calcinations were mixed with aluminum nanoparticles to prepare nanoenergetic composites. The burn rate of the nanocomposites containing ordered mesoporous Fe2O3 mixed with Al nanoparticles was compared with the one containing Fe2O3 with no ordering of mesopores and Al nanoparticles. 相似文献
48.
Shriyesh Patel Sneha Shende Sumit Arora Ashish K Singh 《International Journal of Dairy Technology》2013,66(2):207-213
A coriander extract was evaluated for its potential to increase oxidative stability of ghee. Antioxidant activity using β‐carotene–linoleic acid model system and radical scavenging activity by 2‐diphenyl‐1‐picrylhydrazyl hydrate free (DPPH) was higher in steam distilled extract compared to its oleoresin counterpart. Steam distilled extract and oleoresin were significantly effective in retarding the deterioration of ghee relative to control, as observed in peroxide value, conjugated dienes, thiobarbituric acid (TBA) value and oxidative stability index at the end of 21 days of storage. However, these were less effective than butylated hydroxyanisole (BHA). During deep fat frying, steam distilled extracts showed higher antioxidant activity compared to oleoresin and BHA. 相似文献
49.
Mesoporous ZrO2-modified coupled ZnO/TiO2 nanocomposites were prepared by a surfactant assisted sol–gel method. The photocatalytic performance of these materials was investigated for H2 evolution without noble metal co-catalyst using aqueous methanol media under AM1.5 simulated light. The H2 evolution was compared with coupled ZnO/TiO2, TiO2, ZnO and Degussa P25. The ZrO2-modified nanocomposites exhibited higher H2 generation, specifically 0.5 wt.% ZrO2 loading produced 30.78 mmol H2 g−1 compared to 3.55 mmol H2 g−1 obtained with coupled ZnO/TiO2. A multiple absorbance thresholds at 435 nm and 417 nm were observed with 0.5 wt.% ZrO2 loading, corresponding to 2.85 eV and 2.97 eV band gap energies. The high surface area, large pore volume, uniform crystallite sizes and enhanced light harvesting observed in ZrO2-modified nanocomposites were contributing factors for effective charge separation and higher H2 production. The possible mechanism of H2 generation from aqueous methanol solution over ZrO2-modified nanocomposite is presented. 相似文献
50.
Liposomes containing phosphatidylcholine and cholesterol (uncoated) and coated by chitosan, gelatin, and combination of chitosan and gelatin were prepared by the modified ethanol injection method. The aim of this work was to formulate and characterize liposomes of camptothecin (CPT)-11-HCl (Irinotecan HCl) containing chitosan, gelatin, and both polymers as coating materials; and also to increase its circulation longevity when compared with the free drug while maintaining the agent in its active lactone form. Size, shape, zeta potential, encapsulation efficiency, stability study, in vitro, and in vivo release study were used for characterization of liposomes. The size of liposomes was in the order of uncoated < chitosan coated < gelatin coated < combination of chitosan and gelatin coated. The zeta potential of liposomes was in the order of combination of chitosan and gelatin coated > chitosan coated > gelatin coated > uncoated. The formulations showed the long-term stability. The encapsulation efficiency of liposomes was in order of combination of chitosan and gelatin coated > gelatin coated > chitosan coated > uncoated. The in vitro and in vivo release of drug was observed in the order of combination chitosan and gelatin coated > gelatin coated > chitosan coated > uncoated. 相似文献