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141.
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
142.
Arthur CJ Szafranska AE Long J Mills J Cox RJ Findlow SC Simpson TJ Crump MP Crosby J 《Chemistry & biology》2006,13(6):587-596
Acyl carrier proteins (ACPs) play a fundamental role in directing intermediates among the enzyme active sites of fatty acid and polyketide synthases (PKSs). In this paper, we demonstrate that the Streptomyces coelicolor (S. coelicolor) actinorhodin (act) PKS ACP can catalyze transfer of malonate to type II S. coelicolor fatty acid synthase (FAS) and other PKS ACPs in vitro. The reciprocal transfer from S. coelicolor FAS ACP to a PKS ACP was not observed. Several mutations in both act ACP and S. coelicolor FAS ACP could be classified by their participation in either donation or acceptance of this malonyl group. These mutations indicated that self-malonylation and malonyl transfer could be completely decoupled, implying that they were separate processes and that a FAS ACP could be converted from a non-malonyl-transferring protein to one with malonyl transferase activity. 相似文献
143.
Finite element micromechanics model of impact compression of closed-cell polymer foams 总被引:1,自引:0,他引:1
N.J. Mills R. Stämpfli F. Marone P.A. Brühwiler 《International Journal of Solids and Structures》2009,46(3-4):677-697
Finite element analysis, of regular Kelvin foam models with all the material in uniform-thickness faces, was used to predict the compressive impact response of low-density closed-cell polyethylene and polystyrene foams. Cell air compression was analysed, treating cells as surface-based fluid cavities. For a typical 1 mm cell size and 50 s?1 impact strain rate, the elastic buckling of cell faces, and pop-in shape inversion of some buckled square faces, caused a non-linear stress strain response before yield. Pairs of plastic hinges formed across hexagonal faces, then yield occurred when trios of faces concertinaed. The predicted compressive yield stresses were close to experimental data, for a range of foam densities. Air compression was the hardening mechanism for engineering strains <0.6, with face-to-face contact also contributing for strains >0.7. Predictions of lateral expansion and residual strains after impact were reasonable. There were no significant changes in the predicted behavior at a compressive strain rate of 500 s?1. 相似文献
144.
Review of nanofluids for heat transfer applications 总被引:2,自引:0,他引:2
Saeid Vafaei 《中国颗粒学报》2009,7(2)
Research on nanofluids has progressed rapidly since its enhanced thermal conductivity was first repotted about a decade ago,though much controversy and inconsistency have been reported,and insufficient understanding of the formulation and mechanism of nanofluids further limits their applications.This work presents a critical review of research on heat transfer applications of nanofluids with the aim of identifying the limiting factors so as to push forward their further development. 相似文献
145.
The ternary rare-earth gallium antimonides, REGaSb(2) (RE = La--Nd, Sm), have been synthesized through reaction of the elements. The structures of SmGaSb(2) (orthorhombic, space group D(5)(2)-C222(1), Z = 4, a = 4.3087(5) A, b = 22.093(4) A, c = 4.3319(4) A) and NdGaSb(2) (tetragonal, space group D(19)(4h)-I4(1)/amd, Z = 8, a = 4.3486(3) A, c = 44.579(8) A) have been determined by single-crystal X-ray diffraction. The SmGaSb(2)-type structure is adopted for RE = La and Sm, whereas the NdGaSb(2)-type structure is adopted for RE = Ce--Nd. The layered SmGaSb(2) and NdGaSb(2) structures are stacking variants of each other. In both structures, two-dimensional layers of composition (2)(infinity)[GaSb] are separated from square nets of Sb atoms [Sb] by RE atoms. Alternatively, the structures may be considered as resulting from the insertion of zigzag Ga chains between (2)(infinity)[RE Sb(2)] slabs. In SmGaSb(2), all of the Ga chains are parallel and the (2)(infinity)[SmSb(2)] layers are stacked in a ZrSi(2)-type arrangement. In NdGaSb(2), the Ga chains alternate in direction, resulting in a doubling of the long axis relative to SmGaSb(2), and the (2)(infinity)[NdSb(2)] layers are stacked in a Zr(3)Al(4)Si(5)-type arrangement. Extended Hückel band structure calculations are used to explain the bonding in the [GaSb(2)](3-) substructure. 相似文献
146.
147.
Vijay S. Parmar Dr. David P. Mills Prof. Richard E. P. Winpenny 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(28):7625-7645
Recent studies have shown that mononuclear lanthanide (Ln) complexes can be high-performing single-molecule magnets (SMMs). Recently, there has been an influx of mononuclear Ln alkoxide and aryloxide SMMs, which have provided the necessary geometrical control to improve SMM properties and to allow the intricate relaxation dynamics of Ln SMMs to be studied in detail. Here non-aqueous Ln alkoxide and aryloxide chemistry applied to the synthesis of low-coordinate mononuclear Ln SMMs are reviewed. The focus is on mononuclear DyIII alkoxide and aryloxide SMMs with coordination numbers up to eight, covering synthesis, solid-state structures and magnetic attributes. Brief overviews are also provided of mononuclear TbIII, HoIII, ErIII and YbIII alkoxide and aryloxide SMMs. 相似文献
148.
A total synthesis of the 5-ylidenepyrrole-2-one pukeleimide A (3), a constituent of the marine blue-green alga , is described. 相似文献
149.
A. P. Mills Jr. 《Hyperfine Interactions》1989,44(1-4):105-123
We review the physics of the negative affinity and hot-positron moderators that allow us to produce intense beams of slow
positrons. By repeated staes of remoderation a positron beam can be focused to a microscopic spot on a solid target with little
loss of intensity. The positronium (Ps) and positronium negative ions (Ps−) produced by such a spot will be bright enough to permit the formation of well-collimated Ps beams suitable for gravitational
free fall and other experiments. 相似文献
150.
Eugene Mills 《Acta Analytica》2006,21(4):50-61
Any satisfactory account of freedom must capture, or at least permit, the mysteriousness of freedom—a “sweet” mystery involving a certain kind of ignorance rather than a “sour” mystery of unintelligibility, incoherence,
or unjustifiedness. I argue that compatibilism can capture the sweet mystery of freedom. I argue first that an action is free
if and only if a certain “rationality constraint” is satisfied, and that nothing in standard libertarian accounts of freedom
entails its satisfaction. Satisfaction of this constraint is consistent with the universal causal predetermination of action
(UCP). If UCP is true and the rationality constraint satisfied, there’s a sense in which our actions are explanatorily (though
not necessarily causally) overdetermined. While it seems plausible (given UCP) that our actions are so overdetermined, it seems utterly mysterious why they should be so overdetermined. Compatibilism’s capacity to accommodate this mystery is a mark in its favor. 相似文献