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11.
Kristin Geddes Gary Adamson Neal Dube Susan Crathern Richard C. King 《Rapid communications in mass spectrometry : RCM》2009,23(9):1303-1312
This paper describes an automated workflow for the determination of selected reaction monitoring (SRM) transitions and optimum mass spectrometric (MS) instrument parameters. The approach uses a Nanomate from Advion Biosciences for automated infusion of small amounts of sample in combination with Automaton optimization software from Sciex. The results are stored in the Analyst software Compound Database for automated acquisition method building. Comparisons are presented between the more traditional optimization methods of manual flow injection optimization, Autotune infusion optimization, Automaton flow injection optimization and the Nanomate–Automaton optimization approach. Data is also presented to show that acquisition methods developed on the Sciex model API3000 instrument can be effectively transferred to the Sceix API4000 and API5000 model instruments. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
12.
A comparative study with a vertically integrated model and the multi-level model has shown that the former can remain a good substitute for the latter in the prediction of sea-surface elevation as long as the bottom friction coefficients in the vertically integrated models are properly specified. 相似文献
13.
We define the notion of weak pseudocompactness for frames and present several characterizations. Among them are characterizations
in terms of strong inclusions, uniformities and cozero bases. Noteworthy is the fact that these internal characterizations
are not translated from characterizations of weakly pseudocompact spaces.
相似文献
14.
Binary mixtures of ethylene glycols HO(CH2CH2O)xH (x = 3–5) with glycerol were investigated by fast atom bombardment mass Spectrometry. The relative intensities in the ethylene glycol partial mass spectra as a function of concentration exhibit a steep slope in the low concentration range. With increasing concentration the curves asymptotically approach the 100% line. This effect increases from triethylene to pentaethylene glycol. Comparison of these results with those of surface tension measurements leads to the conclusion that the high sensitivity of fast atom bombardment mass Spectrometry for ethylene glycols is caused by the surface-active properties of these compounds, which lead to an enrichment of the surface investigated with the substance molecules. 相似文献
15.
Themba Dube Inderasan Naidoo 《Topology and its Applications》2011,158(16):2257-2259
We address and correct an oversight that we have identified in Lemma 3.2 of Dube and Naidoo (2010) [2] and provide counterexamples to the original assertions. 相似文献
16.
17.
A frame homomorphism is coz-onto if it maps the cozero part of its domain surjectively onto that of its codomain. This captures the notion of a z-embedded subspace of a topological space in a point-free setting. We give three different types of characterizations of coz-onto homomorphisms. The first is in terms of elements, the second in terms of quotients, and the last in terms of ideals. As an application of properties of coz-onto homomorphisms developed herein, we present some characterizations of $F$ - and $F^{\prime }$ -frames. 相似文献
18.
Yu X Mailman A Dube PA Assoud A Oakley RT 《Chemical communications (Cambridge, England)》2011,47(16):4655-4657
The alternating ABABAB π-stacked bis-1,2,3-dithiazolyl radical 2a (2, R(2)=Ph) has a conductivity σ of 3×10(-5) S cm(-1) at 300 K, and orders as a spin-canted antiferromagnet (T(N)=4.5 K) which undergoes a spin-flop transition to a field-induced ferromagnetic state saturating (at 2 K) at H ~20 kOe. 相似文献
19.
Betelhem Sirak Kaleab Asres Asrat Hailu Mthandazo Dube Norbert Arnold Cecile Hberli Jennifer Keiser Peter Imming 《Molecules (Basel, Switzerland)》2021,26(24)
Leishmaniasis and schistosomiasis are neglected tropical diseases (NTDs) infecting the world’s poorest populations. Effectiveness of the current antileishmanial and antischistosomal therapies are significantly declining, which calls for an urgent need of new effective and safe drugs. In Ethiopia fresh leaves of Ranunculus multifidus Forsk. are traditionally used for the treatment of various ailments including leishmaniasis and eradication of intestinal worms. In the current study, anemonin isolated from the fresh leaves of R. multifidus was assessed for its in vitro antileishmanial and antischistosomal activities. Anemonin was isolated from the hydro-distilled extract of the leaves of R. multifidus. Antileishmanial activity was assessed on clinical isolates of the promastigote and amastigote forms of Leishmania aethiopica and L. donovani clinical isolates. Resazurin reduction assay was used to determine antipromastigote activity, while macrophages were employed for antiamastigote and cytotoxicity assays. Antischistosomal assays were performed against adult Schistosoma mansoni and newly transformed schistosomules (NTS). Anemonin displayed significant antileishmanial activity with IC50 values of 1.33 nM and 1.58 nM against promastigotes and 1.24 nM and 1.91 nM against amastigotes of L. aethiopica and L. donovani, respectively. It also showed moderate activity against adult S. mansoni and NTS (49% activity against adult S. mansoni at 10 µM and 41% activity against NTS at 1 µM). The results obtained in this investigation indicate that anemonin has the potential to be used as a template for designing novel antileishmanial and antischistosomal pharmacophores. 相似文献
20.