An efficient in vitro process for rapid production of cloned plants of Uraria picta has been developed employing nodal stem segments taken from field-grown plants. Explants showed bud-break followed by regeneration
of shoots with restricted growth within 12 days on modified Murashige and Skoog’s medium supplemented with 0.25 mg l–1 each of 6-benzylaminopurine and indole-3-acetic acid and 25 mg l-1 adenine sulfate. Normal growth of shoots with good proliferation rate was achieved by reducing the concentrations of 6-benzylaminopurine
and indole-3-acetic acid to 0.1 mg l-1 each and incorporating 0.5 mg l-1 gibberellic acid in the medium in which, on an average, 19.6 shoots per explant were produced. Further, during successive
subcultures, increased concentrations of adenine sulfate (50 mg l-l) and gibberellic acid (2 mg l-l) along with the addition of 20 mg l-l
dl-tryptophan were found conducive to control the problem of necrosis of shoots. In this treatment, several “crops” of shoots
were obtained from single culture by repeated subculturing of basal portion of stalk in long-term. Isolated shoots rooted
100% in 0.25 mg l-1 indole-3-butyric acid. In vitro-raised plants after hardening in inorganic salt solution grew normally in soil and came to
flowering. Genetic fidelity of in vitro-raised plants was ascertained by rapid amplified polymorphic DNA (RAPD) markers. Also,
quantitative estimation of two isoflavonones in their root extracts further confirmed true-to-type nature of plantlets. 相似文献
Reaction of [VO(OPri)3] (1) with [O(CH2CH2OH)2] in 1:1 molar ratio in anhydrous benzene yield glycol-modified precursor, [VO{OCH2CH2OCH2CH2O}{OPri}] (2). Further reactions of (2) with internally functionalized oximes in anhydrous benzene yield heteroleptic complexes of the type [VO{OCH2CH2OCH2CH2O}{ON=C(R)(Ar)}] (3–8) {where R=CH3, Ar=C4H3O-2 (3), C4H3S-2 (4), C5H4N-2 (5); and when R=H, Ar=C4H3O-2 (6), C4H3S-2 (7), C5H4N-2 (8)}. All these derivatives have been characterized by elemental analyses, molecular weight measurements and spectroscopic techniques. The crysoscopic molecular weight measurement as well as FAB mass study suggests dimeric nature of (2). However, FAB mass spectrum of (4), and the crysoscopic molecular weight measurements of (3), (4), (5) and (6) indicate the monomeric behavior of the oximato derivatives (3–8). Hexa-coordination around vanadium(V) has been proposed for both monomeric and dimeric derivatives. Sol–gel transformations of (1), (2) or (4) to vanadia [(a), (b) or (c), respectively] have been carried out at low sintering temperature (600 °C). The XRD patterns of (a), (b) or (c) indicate formation of a single orthorhombic phase in all the three cases. The SEM images suggest grain like [for (a) and (b)] and rod like [for (c)] morphology of the crystallites. IR, Raman spectra as well as EDX analyses indicate formation of pure vanadia. Absorption spectra of the vanadia (b) and (c) suggest energy band gaps of 2.53 and 2.65 eV, respectively. 相似文献
A novel PCD/CUR self‐assembly approach for improved curcumin delivery to prostate cancer cells is described. The formation of PCD/CUR was confirmed using FTIR, DSC, TGA, and SEM/TEM, and their stability and solubility under physiological conditions was demonstrated. A mechanism for self‐assembly is proposed. Intracellular uptake of the self‐assemblies was studied by flow cytometry and immunofluorescence microscopy. The therapeutic efficacy was determined by cell proliferation and colony formation assays using C4‐2, DU145 and PC3 prostate cancer cells. The results suggest that the PCD/CUR formulation could be a useful system for improving curcumin delivery and its therapeutic efficacy in prostate cancer.
Heath and Vergara [Sorting by short block moves, Algorithmica 28 (2000) 323-352] proved the equivalence between sorting by 3-bounded transpositions and sorting by correcting skips and correcting hops. This paper explores various algorithmic as well as combinatorial aspects of correcting skips/hops, with the aim of understanding 3-bounded transpositions better.We show that to sort any permutation via correcting hops and skips, ⌊n/2⌋ correcting skips suffice. We also present a tighter analysis of the approximation algorithm of Heath and Vergara, and a possible simplification. Along the way, we study the class Hn of those permutations of Sn which can be sorted using correcting hops alone, and characterize large subsets of this class. We obtain a combinatorial characterization of the set Gn⊆Sn of all correcting-hop-free permutations, and describe a linear-time algorithm to optimally sort such permutations. We also show how to efficiently sort a permutation with a minimum number of correcting moves. 相似文献
A simple method for estimating the activation sensitivity of an element/isotope, activated with cyclotron produced fast neutrons, has been developed. It uses the measured neutron spectra produced by bombarding a thick Be target with deuterons of different energies (15-54 MeV) and the measured/estimated neutron cross sections for the particular nuclear reaction. This method is applicable to all sorts of neutron spectra and all the elements/isotopes, whose cross sections/excitation functions in the relevant energy ranges, are available. We have applied this method to estimate the activation sensitivities of a number of lighter elements of biomedical interest. It is pointed out that this simple method is much cheaper, more convenient and quicker in estimating the activation sensitivities than experimental measurements - of course as long as the appropriate excitation functions are available. 相似文献
Photogalvanic effects were studied in photogalvanic cells containing sodium lauryl sulphate as surfactant, EDTA as reductant
and azur-B as photosensitizer. The photopotential and photocurrent generated were 814#x00B7;0 mV and 255·0 μA respectively.
The observed conversion efficiency was 1·2% and the maximum power of cell was 207·57 μW. The storage capacity of the cell
was 26#x00B7;0 min in dark. The effect of different parameters on electrical output of the cell was observed. A mechanism
has been proposed here for the generation of photocurrent in photogalvanic cells 相似文献
Sulfated galactans of the red seaweed species Champia indica and Champia parvula of Indian waters were extracted and purified by ion exchange chromatography. These were characterized by infrared and 13C NMR spectroscopy as well as by GC-MS analysis of alditol acetate derivatives produced by reductive hydrolysis/acetylation of sulfated and desulfated and their methylated samples. The sulfated galactans of these Champia species contained alternating β-(1→3)-linked galactopyranosyl units with sulfation at the 2-position and α-(1→4)-linked galactopyranosyl units having sulfation at both the 2- and 3-positions. Other minor substitutions included 6-O-methyl ether of the β-(1→3)-linked galactose residues only in Champia parvula. 相似文献
By making use of the 19F(p,αγ)16O reaction the F-concentrations of different varieties of tea leaves, of some international geochemical reference materials,
and of the bones and teeth of some experimental animals have been determined. The tea leaves from Ceylon (ordinary), Orange
Pekoe (special Ceylon), China (ordinary black), Lapsang Souchong (special smoked Chinese) and Darjeeling (India) were found
to contain 170 ppm, 170 ppm, 120 ppm, 160 ppm and 100 ppm of fluorine, respectively, The F-concentrations of established geochemical
reference materials, NIM-D, NIM-N, NIM-P and NIM-S, from the National Institute of Metallurgy, South Africa were determined
to be 60 ppm, 120 ppm, 130 ppm and 190 ppm, respectively. The bones of rabbits, who were given fluoridated water, were found
to contain much higher amount of fluorine than the bones of the control rabbit. Furthermore, the rabbits who were kept on
fluoridated water for 45 days, had almost double the amount of F in their bones than the rabbits who were given fluoridated
water for only 15 days. Similarly, the teeth of grown-up monkeys who were given fluoridated water since birth had double the
amount of fluorine than those of the control monkey. 相似文献