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141.
142.
Nowadays, the mangrove biome is considered to be a profound resource of natural products usually possessing cytotoxicity of a broader range. Covering the period 2007–2015, a total of 21 new naturally occurring compounds has stood out. For example, xylogranin B and swietephragmin C were found to exhibit very potent cytotoxic activity against the colon HCT-116 cells reaching IC50 values of 0.05 and 0.06 μM, respectively. Bearing in mind the efficacy of the majority compounds in the preliminary in vitro screens, these studies should be expanded to both ex vivo and in vivo screens including the evaluation of the relevant toxicological profiles. 相似文献
143.
Nick Brettell Jake Horsfield Andrea Munaro Giacomo Paesani Daniël Paulusma 《Journal of Graph Theory》2022,99(1):117-151
A large number of -hard graph problems are solvable in time when parameterized by some width parameter. Hence, when solving problems on special graph classes, it is helpful to know if the graph class under consideration has bounded width. In this paper we consider maximum-induced matching width (mim-width), a particularly general width parameter that has a number of algorithmic applications whenever a decomposition is “quickly computable” for the graph class under consideration. We start by extending the toolkit for proving (un)boundedness of mim-width of graph classes. By combining our new techniques with known ones we then initiate a systematic study into bounding mim-width from the perspective of hereditary graph classes, and make a comparison with clique-width, a more restrictive width parameter that has been well studied. We prove that for a given graph , the class of -free graphs has bounded mim-width if and only if it has bounded clique-width. We show that the same is not true for -free graphs. We identify several general classes of -free graphs having unbounded clique-width, but bounded mim-width; moreover, we show that a branch decomposition of constant mim-width can be found in polynomial time for these classes. Hence, these results have algorithmic implications: when the input is restricted to such a class of -free graphs, many problems become polynomial-time solvable, including classical problems, such as - Colouring and Independent Set , domination-type problems known as Locally Checkable Vertex Subset and Vertex Partitioning (LC-VSVP) problems, and distance versions of LC-VSVP problems, to name just a few. We also prove a number of new results showing that, for certain and , the class of -free graphs has unbounded mim-width. Boundedness of clique-width implies boundedness of mim-width. By combining our results with the known bounded cases for clique-width, we present summary theorems of the current state of the art for the boundedness of mim-width for -free graphs. In particular, we classify the mim-width of -free graphs for all pairs with . When and are connected graphs, we classify all pairs except for one remaining infinite family and a few isolated cases. 相似文献
144.
This review covers the activation, aggregation and degradation of white phosphorus by molecules containing reactive p-block centers. The chemistry has been divided into a number of reaction types and possible mechanisms are used to aid in the understanding of these reactions. 相似文献
145.
146.
Gerald Tuskan Darrell West Harvey D. Bradshaw David Neale Mitch Sewell Nick Wheeler Bob Megraw Keith Jech Art Wiselogel Robert Evans Carolyn Elam Mark Davis Ron Dinus 《Applied biochemistry and biotechnology》1999,77(1-3):55-65
Two new high-through put techniques, computer tomography X-ray densitometry (CT scan) and pyrolysis molecular beam mass spectrometry
(pyMBMS), coupled with quantitative trait loci (QTL) analysis, were tested as a means to overcome the time and cost associated
with conventional characterization of biomass feedstock components. Applications of these two techniques were evaluated using
hybrid poplar for the CT scan and loblolly pine for the pyMBMS. Segregating progeny from hybrid poplar varied in specific
gravity, with individual mean estimates ranging from 0.21–0.41. Progeny from loblolly pine varied in lignin, α cellulose,
and mannan contents, with individual mean estimates of lignin content ranging from 28.7–33.1%, α cellulose content from 28.8–43.5%
and mannan content from 4.2–10.1%. QTL analysis of the loblolly pine data suggested that eleven QTLs were associated with
individual feedstock characteristics and that two QTLs for several feedstock components were linked to the same position on
the loblolly pine genetic map. Each QTL individually accounted for 7–13% of the total phenotypic variation in associated loblolly
pine feedstock components. 相似文献
147.
Nick Serpone Satoshi Horikoshi Alexei V. Emeline 《Journal of Photochemistry and Photobiology, C: Photochemistry Reviews》2010,11(2-3):114-131
This review article focuses, albeit non-exhaustively, on the influence of microwave radiation on photoassisted processes often referred to as Advanced Oxidation Processes. In particular, we describe and illustrate the possible advantages of microwaves in TiO2-assisted photodegradations and photomineralizations of various organic pollutants such as herbicides and endocrine disruptors, among others. Described are also various reactor configurations involving UV/visible radiation and microwaves, with the former being supplied either by traditional Hg lamps or alternatively by electrodeless lamps activated by microwaves. To place the use of microwaves on processes occurring in aqueous TiO2 dispersions in perspective regarding environmental applications, we first introduce the various sources of pollutants and subsequently describe in brief the various advanced oxidation processes such as UV/peroxidation, UV/ozonation and the photo-Fenton process(es) in addition to direct photolysis either by sunlight or by artificial light sources. 相似文献
148.
We compute the force and torque between well-separated, slowly-moving Giant Magnons with arbitrary orientations on S5. We propose an effective Hamiltonian for Giant Magnons in this regime. 相似文献
149.
Wouter A. Herrebout Prof. Nick Nagels Benjamin J. van der Veken Prof. 《Chemphyschem》2009,10(17):3054-3060
Infrared and Raman spectra of solutions in liquid argon and krypton containing dimethyl ether or its fully deuterated isotopomer and 12CO2 or 13CO2 are investigated. The spectra lead to new data on the ν1/2 ν2 resonances appearing in the complex of CO2 with the ether. The experimental data, and their interpretation, is supported by MP2/6‐311++G(2d,2p) calculations of the cubic and quartic force constants and of the first and higher order dipole moment derivatives required for the modelling of the Fermi and Darling‐Dennison resonances observed. 相似文献
150.
Nick Dungey 《Journal of Functional Analysis》2009,256(5):1387-1407
There is a standard notion of type for a sectorial linear operator acting in a Banach space. We introduce a notion of asymptotic type for a linear operator V, involving estimates on the resolvent −1(λI+V) as λ→0. We show, for example, that if V is sectorial and of asymptotic type ω then the fractional power Vα is of asymptotic type αω for a suitable range of positive α. Moreover, we establish various properties of the operator ; in particular, this operator is of asymptotic type 0, for a sectorial operator V. This result has an application to the construction of operators satisfying the well-known Ritt resolvent condition. 相似文献