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In order to study the inheritance pattern of morpho-physiological traits in bread wheat, a 10×10 diallel cross, excluding reciprocals was made and grown in a randomized complete block design (RCBD) with three replications. Observations were recorded on Days to 75% flowering (DF), Days to maturity (DM), Duration of reproductive phase (DRP), Plant height (cm) (PH), Effective tiller/plant (TLS), No. of spikelets per spike (SLS), No. of grains per spike (GS), Grain weight per spike (g) (GW), Spike length (cm) (SL), Biological yield per plant (g) (BY), Harvest index (%) (HI), 1000-Grain weight (g) (TGW), Spike density (SD), Canopy temperature depression (°C) (CTD), Chlorophyll intensity (%) (CI), Chlorophyll fluorescence (Fv/Fm) (CF), Protein content (%) (PC), Grain yield per plant (g) (GY). Highly significant differences were observed among the genotypes for all traits. The resulted 45 F1s and their F2s used for study the nature of gene for grain yield and its contributing traits in bread wheat. The result indicated that considerable gene action and average degree of dominance respond to achieving significant result for grain yield and its component traits. In both the generations F1s and F2s, grain yield per plant (g) was governed by non-additive gene action based on combining ability analysis, (σ2 g/σ2 s)0.5 [GCA and SCA variance ratio] and (H1/D)0.5 [Degree of dominance] were exhibited over dominance type average degree of dominance for grain yield and its component traits in both generations. Genetic analyses of the traits confirm the involvement of both additive and non-additive gene effects in governing the inheritance.

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Abstract

Chromite Spinel materials were synthesized in this study by the citrate precursor method using four divalent cations (Ni2+, Co2+, Zn2+, and Cu2+). Citrate precursors consisting of mixed chromium citrates were first subjected to a thermogravimetric (TG) analysis for determining optimum temperatures for annealing. TG of coprecipitated chromium(III) citrate–zinc citrate gel has been carried out separately in N2 and O2 atmospheres. In both the cases, dehydration is followed by a four-step decomposition. The TG data were subjected to kinetic/mechanistic analysis, and the values of activation energy and Arrhenius factor were approximated. TG curves of various powders which were obtained on annealing at the two temperatures did exhibit thermal instability when carried out in N2 atmosphere. A large coercivity of 2701.01 Oe was observed for NiCr2O4 at 650 °C. On the basis of the results, 450 °C has been chosen for annealing treatment of the four gels. The samples were accordingly annealed at two different temperatures (450 and 650 °C) in a muffle furnace for 1 h in each case. The annealed powders were characterized using X-ray diffraction (XRD), SEM, and vibrating sample magnetometer (VSM). The XRD patterns show that annealing of CuCr2O4, NiCr2O4, and CoCr2O4 at 450 °C yields very small crystallites with poor Bragg reflections, although ZnCr2O4 samples show better peaks in XRD data. Annealing at 650 °C resulted in particle size range of 8–89 nm in the four cases. In the case of ZnCr2O4, the particle size was 8 nm.

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Summary

Herein, the isolation, characterization, and method validation of 5 bioactive terpenoids, viz., taraxerol (1), 3ß-hydroxyoleanane-12-one (2), betulinic acid (3), ursolic acid (4), and oleanolic acid (5) from Codonopsis ovata has been reported. A novel, accurate, and cost-effective high-performance thin-layer chromatography method was developed for the simultaneous quantification of 5 natural products on silica-gel 60 F254 plate using a ternary solvent system, n-hexane-ethyl acetate-formic acid (8.0:2.0:0.4, V/V). Markers were quantified after post-chromatographic derivatization with ceric ammonium sulfate reagent. The developed method was validated as per the International Conference on Harmonization (ICH) guidelines. All calibration curves showed a good linear relationship (r > 0.995) within the test range. Precision was evaluated by intra- and inter-day tests with relative standard deviations <1.99%, and accuracy validation recovery 85.66–91.87 with relative standard deviations >2.00°%. Oleanolic acid (5) and ursolic acid (4) were found in major quantity which is advantageous because of their anticancer, anti-inflammatory, anti-mutagenic, and anti-obesity activities. Based on our results, the developed method features good quantification parameters and can serve as an effective quality control method for standardization of Codonopsis ovata.

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Abstract

Magnetic nanoparticles of cobalt ferrite have been synthesized by citrate precursor method. TG-DSC studies have been made to get the idea of the optimum temperature of annealing that could lead to the formation of nanoparticles. Annealing the citrate precursor was done at 450, 650, and 973 °C. The X-ray diffraction (XRD) studies and the scanning electron microscopy (SEM) have been used for characterization. The data from vibrating sample magnetometer and photoluminescence spectrometer (PL) have been analyzed for exploring their applications. Using the Scherrer formula, the crystallite size was found to be 25, 32, and 43 nm, respectively, using the three temperatures. The particle size increased with annealing temperature. Rietveld refinements on the X-ray (XRD) data were done on the cobalt ferrite nanoparticles (monoclinic cells) obtained on annealing at 650 °C, selecting the space group P2/M. The values of coercivity (1574.4 G) and retentivity (18.705 emu g−1) were found out in the sample annealed at 650 °C while magnetization (39.032 emu g−1) was also found in the sample annealed at 973 °C. The photoluminescence (PL) property of these samples were studied using 225, 330, and 350 nm excitation wavelength radiation source. The PL intensity was found to be increasing with the particle size.

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Abstract  

Binary blends of poly (ether sulphone) (PES) and Nylon-6 were prepared in a whole range of composition by melt extrusion. Miscibility behaviour of the blends were studied using thermal analytical techniques like differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). Due to the rapid crystallization of Nylon-6 as it is cooled from the melt state, its glass transition behaviour could not be detected even in the quenched samples by DSC. Furthermore, the crystallization and melting behaviour of the blends have been studied by DSC. DMA results show that the dynamic storage modulus of the blends were in-between those of the constituent polymers. Also the glass transition of Nylon-6 phase as determined by the peak in loss tangent remains constant which shows that the two polymers are immiscible. Thermal expansion coefficient of the blends as determined by TMA is greater than that of Nylon-6 signifying the increased dimensional stability of the blends at higher temperatures. Morphological studies done by scanning electron microscopy (SEM) show the biphasic nature of the blends, with clear cut boundaries between the phases because of poor interfacial adhesion. Dispersed particle size is small when Nylon-6 is the dispersed phase because of its lower melt viscosity as compared to PES. Thermal stability of the blends was measured using thermogravimetric analysis (TG). Two-step decomposition behaviour was observed because of macro-phase separated morphology.

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Journal of Thermal Analysis and Calorimetry
Authors:
P. Rajagopalan
,
L. Kandpal
,
A. Tewary
,
R. Singh
,
K. Pandey
, and
G. Mathur

Abstract  

PEEK is characterised by high impact and fatigue resistance andT g of 145‡C. Blends of PEEK and PEI have been made and scanning electron micro-graphs of the broken specimen show that the two polymers are completely miscible in all proportions. The study also shows that PEEK∶PEI 50∶50 blend, can be used as matrix for composite applications with appreciable enhancement ofT g to 177‡C.

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Chromium(III) complexes of the type Cr(A)(A′)2, Cr(A)2(A′) and Cr(A)3 have been prepared (whereA is either piperidyldithiocarbamate or morpholyldithiocarbamate andA′ is glycine or oxine or acetylacetone moiety). The mixed ligand complexes have been charac terized by elemental analyses, magnetic susceptibility measurements and thermal studies. The complexes show magnetic moment in the range of 3.5–4.3 B.M. which corresponds to three unpaired electrons. TG studies have also been carried out, in order to study the mode of decomposition of the complexes and to evaluate various kinetic parameters.

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Acta Botanica Hungarica
Authors:
Á. K. Kiss
,
K. Szabó
,
M. K. Singh
, and
L. Gy. Szabó

Hausmann, K., Hülsmann, N. and Radek, R. (2003): Protistology, 3rd completely revised edition. - E. Schweizerbart'sche Verlagsbuchhandlung, Stuttgart, 379 pp. (With  384 figures and 22 tables); Krammer, K. and Lange-Bertalot, H. (2004): Achnanthaceae. Kritische Ergänzungen zu Achnanthes s. l., Navicula s. str., Gomphonema. Gesamtliteraturverzeichnis Teil 2/4. Ergänzter Nachdruck. - In: Ettl, et al. (eds) (2004): Süsswasserflora von Mitteleuropa. Band 2/4. Bacillariophyceae 4. Teil. Spektrum Akademischer Verlag, Heidelberg, Berlin, 468 pp.; Larkum, A. W. D., Douglas, S. E. and Raven, J. A. (eds) (2003): Photosynthesis in algae. - In: Govindjee (ed.): Advances in photosynthesis and respiration. Volume 14. Kluwer Academic Publishers, Dordrecht, Boston, London, 479 pp.; Magurran, A. E. (ed.) (2003): Measuring Biological Diversity. - Blackwell Science Ltd., Blackwell Publishing, Oxford, 260 pp. (ISBN-632-05633-9); Pena, L. (ed.) (2004): Transgenic plants - methods and protocols (Methods in molecular biology, Vol. 286). - Humana Press, Totowa, New Jersey, 437 pp. (ISBN 1-59259-827-7);

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Acta Physiologica Hungarica
Authors:
Szabolcs Varbiro
,
A. Biro
,
J. Cervenak
,
L. Cervenak
,
M. Singh
,
F. Banhidy
,
A. Sebestyen
,
G. Füst
, and
Z. Prohászka

Anti-human Hsp60 autoantibodies — known risk factor of atherosclerosis — were investigated in a mouse model and in samples of healthy subjects: polyreactivity, presence in cord blood samples of healthy newborns and life-long stability were tested. In IgM hybridoma panel from mouse spleens, polyreactivity of anti-Hsp60 autoantibodies was studied. In healthy pregnant women, umbilical vein and maternal blood samples were collected after childbirth, anti-Hsp-60 and -65 IgM and IgG levels were measured. Life-long stability of anti-Hsp-60 levels was studied on healthy patients during 5 years. ELISA was used in all studies. Polyreactivity of IgM clones of newborn mice and lifelong stability of these autoantibodies in healthy adults were established. IgM anti-Hsp60 autoantibodies in cord blood of healthy human infants were present, however, there was no correlation between maternal and cord blood IgM anti-Hsp60 concentrations. It is proposed that presence of anti-Hsp60 autoantibodies — as part of the natural autoantibody repertoire — may be an inherited trait. Level of anti-Hsp60 autoantibodies may be an independent, innate risk factor of atherosclerosis for the adulthood.

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The objective of this study was to develop and validate an assay method for simultaneous determination of atenolol, furosemide, losartan, and spironolactone in pharmaceutical formulations. A reverse-phase high-performance liquid chromatography procedure was developed, using a Kinetex® C-18 column (100 mm × 4.6 mm, 2.6 μm). The mobile phase was composed of methanol—water (75:25 v/v, pH 3.0, adjusted with phosphoric acid), with a flow rate of 0.4 mL min−1. All drugs were separated in less than 5 min. The method was validated according to International Conference on Harmonization (ICH) and Association of Official Analytical Chemists (AOAC) guidelines. The method showed linearity in a concentration range of 0.75–12.0 μg mL−1 for atenolol (r = 0.9995), 0.30–12.00 μg mL−1 for furosemide (r = 0.9997), 0.45–12.00 μg mL−1 for losartan (r = 0.9995), and 0.45–12.0 μg mL−1 for spironolactone (r = 0.9999). The method also showed repeatability and precision. The three-day average intra-day precisions were 101.35 ± 0.74% for atenolol, 95.84 ± 1.44% for furosemide, 98.90 ± 1.16% for losartan, and 97.19 ± 0.18% for spironolactone. Similarly, the inter-day precisions were 101.34 ± 0.72% for atenolol, 95.84 ± 0.1.50% for furosemide, 98.90 ± 1.17% for losartan, and 97.19 ± 0.83% for spironolactone. The method accuracy was also tested and validated — in this case, the average recovery values were 100.18 ± 1.20% for atenolol, 99.83 ± 1.54% for furosemide, 100.07 ± 0.95% for losartan, and 99.94 ± 0.93% for spironolactone. Finally, the method was successfully applied in the simultaneous determination of atenolol, furosemide, losartan, and spironolactone in magisterial formulas, as well as in commercial pharmaceutical formulations.

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