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121.
A systematic evaluation of protocols for a proteomics analysis of (lyophilized) fruit tissues
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Francis O. Amoako‐Andoh Bruno Daniëls Wannes Keulemans Mark W. Davey 《Electrophoresis》2014,35(10):1395-1405
This study represents a systematic evaluation of protocols for protein extraction and cleanup for fruit proteomic analysis. Procedures were optimized using pooled lyophilized banana fruit pulp, which is known to be particularly tricky due to high concentrations of soluble polysaccharides, phenolics, and other substances that interfere with protein extraction and purification. A total of 18 combinations of three protein extraction procedures (SDS‐based, Triton X‐100‐based, and phenol‐based), three protein precipitating agents (ammonium acetate/methanol, TCA/acetone, and acetone), and two resolubilization buffers (classical Rabilloud and the so‐called R2D2) were compared for total protein yields and efficiency of recovery. The results demonstrate that while losses in total recovered protein are unavoidable, the degree of these losses depends on the method combinations used. Combinations based on buffer‐saturated phenol always gave the highest yields, and overall recovery and purity was highest when acetone was combined with the R2D2 buffer for protein purification and concentration. Comparative 2D‐PAGE analysis confirmed that this method combination produced high‐quality and reproducible gels and the largest numbers of spots per gel. The usefulness of this methodology was demonstrated on ripe fruits from several other species and shown to give excellent results. 相似文献
122.
Chidi Amadi-Kamalu Holly Clarke Matthew McRobie James Mortimer Prof. Michael North Yanrui Ran Dr. Anne Routledge Dani Sibbald Matthew Tickias Kai Tse Helen Willway 《ChemistryOpen》2020,9(4):431-441
The influence of various physical and chemical factors on the swelling of polystyrene and PEG based resins in greener organic solvents has been systematically investigated. In general, chemical factors: the nature of the functionality/linker and the degree of loading were found to have a far larger influence on the swelling of the resins than physical parameters such as bead size. The results are interpreted in terms of Hansen solubility parameters for the solvents and there is evidence that some solvents interact with the polymeric core of a resin whilst others interact with the functionality. The results are extended to a study of the changes in resin swelling observed during both deprotection and chain elongation reactions during solid phase peptide synthesis. 相似文献
123.
Ignacio Fernández Nieves Danièle Schott Stefan Gruber Paul S. Pregosin 《Helvetica chimica acta》2007,90(2):271-276
Allylic alcohols, rather than halides, acetates, or carbonates can be used directly in the Friedel–Crafts‐type coupling with various phenols. The use of a RuIV, rather than a RuII, precursor promotes the formation of one H+ per cycle so that a large excess of acid is never present in the reaction mixture. Consequently, the leaving group in the oxidative addition reaction is H2O, thereby avoiding the production of an unnecessary by‐product. 相似文献
124.
De K Legros J Crousse B Chandrasekaran S Bonnet-Delpon D 《Organic & biomolecular chemistry》2011,9(2):347-350
The synthesis of 8-aminoquinolines and 1,10-phenanthrolines with substituents in α of the nitrogen has been performed through an inverse-demanding aza-Diels-Alder (Povarov reaction) in the fluoroalcohols TFE or HFIP. This path involves simple starting materials: 1,2-phenylenediamines, enol ethers and aldehydes. 相似文献
125.
For a regular jointly measurable Markov semigroup on the space of finite Borel measures on a Polish space we give a Yosida-type decomposition of the state space, which yields a parametrisation of the ergodic probability measures associated to this semigroup in terms of subsets of the state space. In this way we extend results by Costa and Dufour (J. Appl. Probab. 43:767?C781, 2006). As a consequence we obtain an integral decomposition of every invariant probability measure in terms of the ergodic probability measures. Our approach is completely centered around the reduction to and relationship with the case of a single regular Markov operator associated to the Markov semigroup, the resolvent operator, which enables us to fully exploit results in that situation (Worm and Hille in Ergod. Theory Dyn. Syst. 31(2):571?C597, 2011). 相似文献
126.
Federica Aiello Marcel G. Simons Jan W. van Velde Paulo Dani 《Molecules (Basel, Switzerland)》2021,26(13)
Pyrethroids are among the insecticidal compounds indicated by the World Health Organization for mitigation of vector-borne diseases. Active deltamethrin (with chiral configuration α-S,1-R-cis) is one of the most effective pyrethroids characterized by low toxicity to humans, and it is currently tested as active ingredient for insecticidal paints. Nevertheless, several degradation processes can occur and affect the insecticidal efficacy in the complex paint matrix. In the present study, a detailed NMR analysis of deltamethrin stability has been carried out under stress conditions, mimicking a water-based insecticidal paint environment. Two novel by-products, having a diastereomeric relationship, were identified and their structure was elucidated by combining NMR, HPLC, GC-MS, and ESI-MS analyses. These compounds are the result from a nucleophilic addition involving deltamethrin and one of its major degradation products, 3-phenoxybenzaldehyde. Given the known toxicity of the aldehyde, this reaction could represent a way to reduce its concentration into the matrix. On the other hand, the toxicology of these compounds towards humans should be addressed, as their presence may adversely affect the performance of deltamethrin-containing products. 相似文献
127.
Sebastian Milster Tobias Grünbaum Dr. Sebastian Bange Simon Kurrmann Hermann Kraus Dr. Dani M. Stoltzfus Dr. Anna E. Leung Dr. Tamim A. Darwish Prof. Paul L. Burn Prof. Dr. Christoph Boehme Prof. Dr. John M. Lupton 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(24):9474-9478
The formation of excitons in OLEDs is spin dependent and can be controlled by electron-paramagnetic resonance, affecting device resistance and electroluminescence yield. We explore electrically detected magnetic resonance in the regime of very low magnetic fields (<1 mT). A pronounced feature emerges at zero field in addition to the conventional spin- Zeeman resonance for which the Larmor frequency matches that of the incident radiation. By comparing a conventional π-conjugated polymer as the active material to a perdeuterated analogue, we demonstrate the interplay between the zero-field feature and local hyperfine fields. The zero-field peak results from a quasistatic magnetic-field effect of the RF radiation for periods comparable to the carrier-pair lifetime. Zeeman resonances are resolved down to 3.2 MHz, approximately twice the Larmor frequency of an electron in Earth's field. However, since reducing hyperfine fields sharpens the Zeeman peak at the cost of an increased zero-field peak, we suggest that this result may constitute a fundamental low-field limit of magnetic resonance in carrier-pair-based systems. OLEDs offer an alternative solid-state platform to investigate the radical-pair mechanism of magnetic-field effects in photochemical reactions, allowing models of biological magnetoreception to be tested by measuring spin decoherence directly in the time domain by pulsed experiments. 相似文献
128.
Errikos Kounalis Dr. Martin Lutz Dr. Ing. Daniël L. J. Broere 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(58):13280-13284
A naphthyridine-derived expanded pincer ligand is described that can host two copper(I) centers. The proton-responsive ligand can undergo reversible partial and full dearomatization of the naphthyridine core, which enables cooperative activation of H2 giving an unusual butterfly-shaped Cu4H2 complex. 相似文献
129.
We consider Markov semigroups on the cone of positive finite measures on a complete separable metric space. Such a semigroup
extends to a semigroup of linear operators on the vector space of measures that typically fails to be strongly continuous
for the total variation norm. First we characterise when the restriction of a Markov semigroup to an invariant L
1-space is strongly continuous. Aided by this result we provide several characterisations of the subspace of strong continuity
for the total variation norm. We prove that this subspace is a projection band in the Banach lattice of finite measures, and
consequently obtain a direct sum decomposition. 相似文献
130.
Daligault, Rao and Thomassé asked whether a hereditary class of graphs well-quasi-ordered by the induced subgraph relation has bounded clique-width. Lozin, Razgon and Zamaraev recently showed that this is not true for classes defined by infinitely many forbidden induced subgraphs. However, in the case of finitely many forbidden induced subgraphs the question remains open and we conjecture that in this case the answer is positive. The conjecture is known to hold for classes of graphs defined by a single forbidden induced subgraph H, as such graphs are well-quasi-ordered and are of bounded clique-width if and only if H is an induced subgraph of P 4. For bigenic classes of graphs, i.e. ones defined by two forbidden induced subgraphs, there are several open cases in both classifications. In the present paper we obtain a number of new results on well-quasi-orderability of bigenic classes, each of which supports the conjecture. 相似文献