90 research outputs found
N-Methylation of 2-Furylhenzothiazoles. The Influence of Substituents on the Rate of Quaternization
Quaternization of several 2-furylbenzothiazoles with dimethylsulphate
in dioxane has been studied. The noticeable substituent
dependence of the rate of methylation has been observed. The
substituents (CHa, Br, Cl) have been located at position 5 of the
furane nucleus and/or position 6 of the benzo-ring
Thioamides. XV. Some New Substituted 2-(2- or 3-Furyl)benzothiazoles. The Preparation and Properties
A number of 2-substituted benzothiazoles with 2-furyl- (Figure
1.) or 3-furyl- (Figure 2.) group as a substituent were prepared
by the oxidative cyclization of corresponding thioanilides. Some of
the prepared benzothiazoles were converted to N-methyl derivatives
with dimethylsulphate. The compounds were isolated as quarternary
salts. The influence of substituents on the basicity of the benzothiazole
nucleus and on the rate of quarternization was established
Book Reviews
Gmelins Handbuch der anorganischen Chemie. 8. Auflage. Herausgegeben vom Gmelin-Institut in Clausthal-Zellerfeld. Hauptredakteur Erich Pietsch. Verlag Chemie, GMBH, Weinheim/Bergstrasse. [I. Filipović]
F. Feigl: Spot Tests. Vol. I. Inorganic Applications. [L. Filipović]
F. Feigl: Spot Tests. Vol. II. Organic Applications. [K. Balenović]
E. de Barry Barnett: Stereochemistry. London, First Published 1950 (Sir Isaac Pitman & Sons, Ltd.) [K. Balenović]
R. J. McIlroy : The Plant Giycosides. London 1951. (Edward Arnold & Co.) [K. Balenović]
J. Timmermans: Les Constantes Physiques des Composes Organiques Cristallises. Paris 1953. [K. Balenović]
Roosevelt Griffiths: Thermostats and Temperature-Regulating Instruments. 3. izdanje, London 1951. (Charles Griffin & Co. Ltd.) [N. Škarica]
Ivan Brihta : Kataliza u kemijskoj industriji, Zagreb 1953. (Tehnička knjiga). [W. A. Fišer
Who dares does not always win: risk-averse rockpool prawns are better at controlling a limited food resource
This is the author accepted manuscript. The final version is available from Elsevier Masson via the DOI in this record.Animal ‘personality’ – the phenomenon of consistent individual differences in behaviour within
populations – has been documented widely, yet its functional significance and the reasons for its
persistence remain unclear. One possibility is that among-individual behavioural variation is linked to
fitness-determining traits via effects on resource acquisition. In this study, we test this idea, using
rockpool prawns (Palaemon elegans) to test for a correlation between ‘high-risk exploration’ and the
ability to monopolise a limited resource. Modified open field trials (OFTs) confirmed that consistent
among-individual (co)variation in high-risk exploratory behaviours does exist in this species, and
multivariate analysis shows trait variation is consistent with a major axis of personality variation.
Subsequent feeding trials in size-matched groups where competition was possible revealed a high
repeatability of feeding duration, used here as a proxy for RHP (resource holding potential). We
found significant negative correlations between feeding duration and two ‘risky’ behaviours, such
that individuals that took fewer risks fed more. Our results are not consistent with the widely
hypothesised idea of a ‘proactive syndrome’ in which bolder, risk-taking personalities are positively
associated with RHP. Rather they suggest the possibility of a trade-off, with some individuals
successful at monopolising limited, high-value resources, while others are more willing to engage in
potentially risky exploration (which may increase the likelihood of encountering novel resource
patches). We speculate that alternative strategies for acquiring limited resources might thereby
contribute to the maintenance of personality variation observed in wild populationsTH and AJW were supported by a grant from the Biotechnology and
Biological Sciences Research Council awarded to AJW (BBSRC, grant BB/L022656/1)
How do anthropogenic contaminants (ACs) affect behaviour? Multi-level analysis of the effects of copper on boldness in hermit crabs
Understanding the cancer stem cell
The last 15 years has seen an explosion of interest in the cancer stem cell (CSC). Although it was initially believed that only a rare population of stem cells are able to undergo self-renewing divisions and differentiate to form all populations within a malignancy, a recent work has shown that these cells may not be as rare as thought first, at least in some malignancies. Improved experimental models are beginning to uncover a less rigid structure to CSC biology, in which the concepts of functional plasticity and clonal evolution must be incorporated into the traditional models. Slowly the genetic programmes and biological processes underlying stem cell biology are being elucidated, opening the door to the development of drugs targeting the CSC. The aim of ongoing research to understand CSCs is to develop novel stem cell-directed treatments, which will reduce therapy resistance, relapse and the toxicity associated with current, non-selective agents
Persistence of phylogeographic footprints helps to understand cryptic diversity detected in two marine amphipods widespread in the Mediterranean basin
Amphipods of the genus Gammarus are a vital component of macrozoobenthic communities in European inland and coastal, marine and brackish waters of the Mediterranean and the Black Sea. Exceptional levels of cryptic diversity have been revealed for several widespread freshwater Gammarus species in Europe. No comprehensive assessment has yet been made for brackishwater counterparts, such as Gammarus aequicauda and G. insensibilis, which are among the most widely dispersed members of the so-called “G. locusta group” in the Mediterranean and in the Black Sea. Here we probe the diversity of these morphospecies examining the partitioning of mtDNA and nDNA across multiple populations along their distribution range and discuss it within the regional paleogeographic framework. We gathered molecular data from a collection of 166 individuals of G. aequicauda and G. insensibilis from 47 locations along their distribution range in the Mediterranean including the Black Sea. They were amplified for both mitochondrial COI and 16S rRNA as well as the nuclear 28S rRNA. All five MOTU delimitation methods (ABGD, BIN, bPTP, GMYC single and multiple threshold models) applied revealed deep divergence between Black Sea and Mediterranean populations in both G. aequicauda and G. insensibilis. There were eight distinct MOTUs delimited for G. aequicauda (6–18% K2P) and 4 MOTUs for G. insensibilis (4–14% K2P). No sympatric MOTUs were detected throughout their distribution range. Multimarker time-calibrated phylogeny indicated that divergence of both G. aequicauda and G. insensibilis species complexes started already in the late Oligocene/early Miocene with the split between clades inhabiting eastern and western part of the Mediterranean occurring in both species at the similar time. Our results indicate a high cryptic diversity within Mediterranean brackishwater Gammarus, similar to that observed for freshwater counterparts. Moreover, the phylogenetic history combined with the current geographic distribution indicate that the evolution of botThis work was supported by Polish National Science Center (projects no. 2014/15/B/NZ8/00266 and 2015/17/N/NZ8/01628) and partially by the statutory funds of the Department of Invertebrate Zoology and Hydrobiology of University of Lodz. F. Costa and the University of Minho contribution was supported by the strategic programme UID/BIA/04050/2013 (POCI-01-0145-FEDER-007569) funded by national funds through the FCT I.P. and by the ERDF through the COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI). There was no additional external funding received for this study. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
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