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61.
Maria A. Mendoza DeEtta K. Mills Hemant Lata Suman Chandra Mahmoud A. ElSohly Jose R. Almirall 《Analytical and bioanalytical chemistry》2009,393(2):719-726
Cannabis sativa is the most frequently used of all illicit drugs in the USA. Cannabis has been used throughout history for its stems in the
production of hemp fiber, seed for oil and food, and buds and leaves as a psychoactive drug. Short tandem repeats (STRs) were
chosen as molecular markers owing to their distinct advantages over other genetic methods. STRs are codominant, can be standardized
such that reproducibility between laboratories can be easily achieved, have a high discrimination power, and can be multiplexed.
In this study, six STR markers previously described for C. sativa were multiplexed into one reaction. The multiplex reaction was able to individualize 98 cannabis samples (14 hemp and 84 marijuana, authenticated as originating from 33 of the 50 states of the USA) and detect
29 alleles averaging 4.8 alleles per loci. The data did not relate the samples from the same state to each other. This is
the first study to report a single-reaction sixplex and apply it to the analysis of almost 100 cannabis samples of known geographic
origin.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
62.
T. A. Lavin S. S. Girimaji S. Suman H. Yu 《Theoretical and Computational Fluid Dynamics》2012,26(6):501-522
We investigate the behavior of flow variables, thermodynamic variables and their interaction in rapidly sheared (S) homogeneous compressible turbulence using rapid distortion theory (RDT). We subject an initially isotropic and incompressible flow field to homogeneous shear-rate of various strengths quantified by a gradient Mach number (M g ) based on characteristic wavenumber. Our objective is to characterize the behavior of flow/thermodynamic fluctuations and their linear interactions during the course of turbulence evolution. Even though the mean shear-rate is held constant, the gradient Mach number progressively diminishes with time as the relevant wavenumber increases due to the mean deformation. The evolution exhibits three distinct phases which we categorize based on the character of pressure as: (i) Pressure-released (PR) stage which is observed when ${St < \sqrt{M_{g0}}}$ and pressure effects are negligible; (ii) Wave-character (WC) stage wherein ${\sqrt{M_{g0}} < St < M_{g0}}$ and the wave character of pressure is in evidence; and (iii) Low-Mach number (LM) stage when St > M g0, where M g0 is the initial gradient Mach number. In the PR regime we find that the thermodynamic fluctuations evolve from their initial state but velocity fluctuations grow unhindered by pressure fluctuations. In the WC regime, the pressure fluctuations become significant and flow-thermodynamic interaction commences. This interaction brings about equipartition of dilatational kinetic energy and thermodynamic potential energy. The interaction also results in stabilization of turbulence, and the total kinetic energy growth comes to a near standstill. Ultimately in the LM stage, kinetic energy starts increasing again with the growth rate being very similar to that in incompressible RDT. However, the thermodynamic fluctuations continue to grow despite the gradient Mach number being substantially smaller than unity. Overall, the study yields valuable insight into the linear processes in high Mach number shear flows and identifies important closure modeling issues. 相似文献
63.
64.
Manandhar Suman Sankhe Runali Priya Keerthi Hari Gangadhar Kumar B. Harish Mehta Chetan H. Nayak Usha Y. Pai K. Sreedhara Ranganath 《Molecular diversity》2022,26(5):2793-2811
Molecular Diversity - Wnt signaling pathway is an evolutionarily conserved pathway responsible for neurogenesis, axon outgrowth, neuronal polarity, synapse formation, and maintenance.... 相似文献
65.
The single crystal X-ray diffraction study of capped γ-peptide reveal that the peptide adopts helical conformation which self-assemble to form a supramolecular parallel double helical structure using intermolecular hydrogen bonding as well as π-π stacking interactions in the solid state. 相似文献
66.
Debapriya Chakraborty Nilanjana Bose Sukanya Sasmal Swagata Dasgupta Tapas K. Maiti Suman Chakraborty Sunando DasGupta 《Analytica chimica acta》2012
Aim of the present work is to investigate the reaction–diffusion process of a two species system under laminar flow in a T-shaped microchannel. A zone formed at the interface between the aqueous solutions of these two species is affected by advection and diffusion. Through theoretical analyses and experimental results, the effect of dispersion has been shown to influence this diffusion zone. We have defined a parameter called effective diffusivity, to account for the dispersion effects and observed it to be a function of the channel Peclet number. In the limiting case of low Peclet number, this parameter is constant and turns out to be equal to the molecular diffusivity. We have also related effective diffusivity and the dispersion coefficient through scaling estimates. 相似文献
67.
J.S. Yadav T. PandurangamA. Suman Kumar P. Adi Narayana ReddyA.R. Prasad B.V. Subba ReddyK. Rajendraprasad A.C. Kunwar 《Tetrahedron letters》2012,53(45):6048-6050
A convergent and highly stereoselective total synthesis of the Z-isomer of cytospolide E has been achieved via Evan’s aldol reaction, Sharpless kinetic resolution and RCM cyclisation. 相似文献
68.
Carolina Lipparelli Morelli José Manoel Marconcini Fabiano Vargas Pereira Rosario Elida Suman Bretas Márcia Cristina Branciforti 《Macromolecular Symposia》2012,319(1):191-195
Summary: In this study cellulose nanowhiskers were obtained from balsa wood. For this purpose, fibers of balsa wood were exposed to hydrolysis reactions for lignin and hemicellulose digestion and acquisition of nano-scale cellulose. Transmission electron microscopy (TEM) results demonstrated that the obtained cellulose nanocrystals had average length and thickness of 176 (±68 nm) and 7.5 (±2.9 nm), respectively. Infrared spectroscopy (FTIR) and wide angle x-ray diffraction (WAXD) showed that the process for extracting the nanowhiskers digested nearly all the lignin and hemicellulose from the balsa fiber and still preserved the aspect ratio and crystallinity satisfactory enough for future application as nanofillers in polymer nanocomposites. The thermogravimetric analysis (TGA) showed that the onset temperature of thermal degradation of the cellulose nanocrystals (226 °C) was higher than the onset temperature of the balsa fiber (215 °C), allowing its use in molding processes with polymers melts. 相似文献
69.
The disturbance caused by the application of continuous mechanical source on the free surface of a homogeneous, isotropic
elastic half space in the context of the theory of generalized thermoelastic diffusion with one relaxation time parameter
is investigated in the Laplace-Fourier transform domain for a two dimensional problem using eigenvalue approach. The integral
transforms are inverted by using a numerical technique. The expressions for displacement components, stresses, temperature
field, concentration and chemical potential so obtained in the physical domain are computed numerically and illustrated graphically
at different times, for copper like material. As a special case the effect of diffusion on various expressions has also been
obtained analytically and depicted graphically. 相似文献
70.
Abstract An efficient, atom-economic, one-pot protocol has been developed for the synthesis of highly functionalized dihydropyridines via four-component reactions of aromatic aldehydes, arylamines, malononitrile, and dimethylacetylenedicarboxylate in the presence of sodium hydroxide in ethanol. This domino reaction proceeded smoothly in good to excellent yields and offered several advantages, including short reaction time, simple experimental procedure, and applicability to a broad range of substrates. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file. 相似文献