Search results for "amine"

Impacts of piscicide-induced fish removal on resource use and trophic diversity of lake invertebrates

2022

Chemical eradication of non-native species has become a widely used method to mitigate the potential negative im- pacts of altered competitive or predatory dynamics on biodiversity and natural ecosystem processes. However, the re- sponses of non-target species can vary from rapid full recovery to delayed or absent recolonization, and little is known about the potential shifts in resource use and trophic diversity of native species following chemical treatments. We used a before-after-control-impact approach to study the effects of rotenone piscicide treatment on abundance and tro- phic niche of benthic invertebrates in three untreated and three treated lakes in central Norway, the latter gr…

How to Become an Author: The Poet Isa Asp and Her Childhood Fascination with Writing for Magazines

2021

In this article the author explores the early development of the identity as a writer of a Finnish-speaking poet Lovisa (or Isa) Asp (1853–1872). She wrote her lyrics in the Finnish language in the 1870s, and she is regarded as the first 19th-century female Finnish poet (whose works were published in Finnish). She began writing poetry (initially in Swedish) as a teenager and started her literary career as a contributor to children’s magazines. Asp began her studies at the Teacher Training College in Jyväskylä in autumn 1871 with the aim of working as an elementary school teacher, but she also dreamt of becoming an established writer someday. Unfortunately, her early death meant that most of…

Rieke Trimçev, Politik als Spiel. Zur Geschichte einer Kontingenzmetapher im politischen Denken des 20. Jahrhunderts. Baden-Baden: Nomos 2018, 398 p.…

2019

Titanium complexes for the formation of nitrogen compounds : synthesis of homoallylamines and amidines

2011

Homoallylic amines are key reagents for the formation of a large number of biologically interesting products. Due to the double bond of their allylic moiety, easily functionalisable, they are commonly used in organic synthesis. This research work deals with the synthesis of homoallylic amines thanks to titanium complexes. In fact, the reductive coupling between of imines and dienes promoted by titanium allows the formation of diastereoisomeric homoallylamines syn and anti. The diastereoselectivity of the reaction is directly affected by the nitrogen substituent. Whether it is benzyl or phenyl, the selectivity will be in favour of syn or anti respectively. Moreover, the addition of a the Lew…

Hindrances to recognition in Finnish music schools

2021

This article examines recognition relations between students and teachers in Finnish music schools. The research is based on written texts by music school students. The texts are analysed for difficulties in recognition relations, namely, hindrances to recognition in music schools. In the texts, some of the respondents describe situations that can be analysed as hindrances to recognition. The author analyses four different types of recognition-related problems in the data, the main issue being a tension between caring for people (respecting them) and promoting musical values (emphasising esteem). In addition to discerning problems, the article attempts to alleviate this tension. This might…

Social Invisibility and Emotional Blindness

2020

The unsettling, humiliating, and often threatening experience of feeling oneself ‘invisible’ before the gazes of other people in one’s social world has obvious potential as a theme for collaborative efforts between social theorists and phenomenologists. This chapter proposes one way of approaching such an engagement, drawing in particular upon three authors who offer detailed analyses of social visibility and its potential pathologies: Axel Honneth, Frantz Fanon, and Edmund Husserl. The specific phenomenon is first be located by way of Honneth’s treatment of social invisibility as frequented by behaviour that expresses an attitude of nonrecognition towards other persons immediately present.…

Modeling Tyrosinase and Catecholase Activity Using New m-Xylyl-Based Ligands with Bidentate Alkylamine Terminal Coordination

2012

Chemical model systems possessing the reactivity aspects of both tyrosinase and catechol oxidase are presented. Using two m-xylyl-based ligands providing bidentate alkylamine terminal coordination, 1,3-bis[(N,N-dimethylaminoethyl)aminomethyl]benzene (L(H,H)) and 1,3-bis[(N,N,N'-trimethylaminoethyl)aminomethyl]benzene (L(Me,Me)), four new dicopper(I) complexes, [Cu(I)(2)(L(H,H))(MeCN)(4)][ClO(4)](2) (1), [Cu(I)(2)(L(H,H))(PPh(3))(2)(MeCN)(2)][ClO(4)](2) (2), [Cu(I)(2)(L(Me,Me))(MeCN)(2)][ClO(4)](2) (3), and [Cu(I)(2)(L(Me,Me))(PPh(3))(2)][ClO(4)](2) (4), have been synthesized and characterized. Complex 2 has been structurally characterized. Reaction of the dicopper(I) complex 3(2+) with diox…

Stabilization of a nutraceutical omega-3 fatty acid by encapsulation in ultrathin electrosprayed zein prolamine.

2010

Docosahexaenoic acid (DHA) is a long chain polyunsaturated fatty acid of the omega-3 series (omega-3), which exerts strong positive influences on human health. The target of this study was the stabilization by encapsulation of this bioactive ingredient in zein ultrathin capsules produced by electrospraying. The zein ultrathin DHA encapsulation was observed by ATR-FTIR spectroscopy to be more efficient against degradation under both ambient conditions and in a confined space (so-called headspace experiment). In the latter case, that more closely simulates a sealed food packaging situation, the bioactive DHA was considerably more stable. By fitting the degradation data to a specific auto-deco…

Amino acid substitutions enhancing thermostability of Bacillus polymyxa beta-glucosidase A

1996

Mutations enhancing the thermostability of β-glucosidase A of Bacillus polymyxa, a family 1 glycosyl hydrolase, have been obtained after hydroxylamine mutagenesis of a plasmid containing the bglA gene, transformation of Escherichia coli with the mutagenized plasmid, and identification of transformant colonies that showed β-glucosidase activity after a thermal treatment that inactivated the wild-type enzyme. Two additive mutations have been characterized that cause replacement of glutamate at position 96 by lysine and of methionine at position 416 by isoleucine respectively. The thermoresistant mutant enzymes showed increased resistance to other denaturing agents, such as pH and urea, while …

Gold-Catalyzed Intramolecular Hydroamination of o-Alkynylbenzyl Carbamates: A Route to Chiral Fluorinated Isoindoline and Isoquinoline Derivatives

2013

Enantiomerically pure fluorinated isoindoline and dihydroisoquinoline scaffolds have been prepared through a diastereoselective addition of fluorinated nucleophiles to Ellman’s N-(tert-butanesulfinyl)imines followed by a sequence of Sonogashira cross-coupling/gold(I)-catalyzed cycloisomerization of the corresponding carbamate. A more favored 5-exo-dig mechanism was observed mainly due to an electronic effect of the fluorinated group.