Search results for "31"
showing 10 items of 4401 documents
Dinuclear Palladium(II) and -(III) Compounds with O,O-Chelating Ligands. Room-Temperature Direct 2-Phenylation of 1-Methylindole
2012
New dinuclear palladium(III) compounds of general formula Pd2[(C6H4)PPh2]2[O–O]2Cl2, O–O being chelating phenolates C6H4OC(O)R (R = CH3, 3a; R = C2H5, 3b; R = OPh, 3c) or acetylacetonates RC(O)CHC(O)R (R = CH3, 4a; R = CF3, 4b; R = C(CH3)3, 4c), have been obtained by oxidation with PhICl2 of the corresponding palladium(II) compounds. The stability of the new compounds has been studied by 31P NMR spectroscopy from 200 to 298 K. DFT calculations of the stability of the complexes have also been performed. In agreement with these calculations, only compound Pd2[(C6H4)PPh2]2[(CF3C(O)CHC(O)CF3]2Cl2, 6b, showed the highest thermal stability. 6b was characterized by X-ray diffraction methods, prese…
NMR spectroscopy in environmental chemistry:1H and13C NMR parameters of tricyclic polychlorinated C10 hydrocarbons and their oxy derivatives based on…
1999
Two-dimensional homo- and heteronuclear NMR chemical shift correlation techniques were applied in the characterization of five tricyclic polychlorinated C10 hydrocarbons, chlordene (1), heptachlor (2), trans-nonachlor (3), α-chlordene (4) and γ-chlordene (5), which are spread globally in the environment owing to their use as insecticides. Approximate and partly contradictory 1H and 13C NMR chemical shifts reported in the literature were corrected in this work. The chemical shift assignments of 1–5 were based on DQF COSY, HMQC and HMBC experiments. In addition, an INADEQUATE experiment was needed to ascertain the 13C chemical shifts assignment of 2. The nJ(H,H)s of 1–5 were solved by compute…
Cobalt bis(dicarbollides)(1-) covalently attached to the calyx[4]arene platform: the first combination of organic bowl-shaped matrices and inorganic …
2005
Various calix[4]arene and resorc[4]arene ionic compounds substituted by cobalt bis(dicarbollide) anions (1) have been prepared for the first time. From tBu-calix[4]arene (A) the complete series of mono-, di-, tri- and tetrasubstituted derivatives bearing one to four cluster anions on the lower rim (3-6) have been obtained in the form of their alkali-metal salts by O-alkylation with the 1-dioxane derivative [8-O(CH2CH2)2O(+)-1,2-C2B9H10)-(1',2'-C2B9H11)-3,3'-Co] (2), all of which are syn or cone isomers. In contrast, disubstitution of the dipropyl ether of tBu-calix[4]arene (B) led to a mixture of the cone and 1,3-alternate conformers 7a and 7b, respectively. Starting from tetrapropoxy-calix…
Self-adjuvanting C18 lipid vinil sulfone-PP2A vaccine: study of the induced immunomodulation against
2017
Despite the importance of the adjuvant in the immunization process, very few adjuvants merge with the antigens in vaccines. A synthetic self-adjuvant oleic-vinyl sulfone (OVS) linked to the catalytic region of recombinant serine/threonine phosphatase 2A from the nematode Angiostrongylus costaricensis (rPP2A) was used for intranasal immunization in mice previously infected with Trichuris muris. The animal intranasal immunization with rPP2A-OVS showed a reduction of 99.01% in the number of the nematode eggs and 97.90% in adult. The immunohistochemical analysis of the intestinal sections showed that in immunized animals with lipopeptide the mucus was significantly higher than in the other expe…
Sensitivity of the Cherenkov Telescope Array to a dark matter signal from the Galactic centre
2021
Full list of authors: Acharyya, A.; Adam, R.; Adams, C.; Agudo, I.; Aguirre-Santaella, A.; Alfaro, R.; Alfaro, J.; Alispach, C.; Aloisio, R.; Alves Batista, R.; Amati, L.; Ambrosi, G.; Angüner, E. O.; Antonelli, L. A.; Aramo, C.; Araudo, A.; Armstrong, T.; Arqueros, F.; Asano, K.; Ascasíbar, Y. Ashley, M.; Balazs, C.; Ballester, O.; Baquero Larriva, A.; Barbosa Martins, V.; Barkov, M.; Barres de Almeida, U.; Barrio, J. A.; Bastieri, D.; Becerra, J.; Beck, G.; Becker Tjus, J.; Benbow, W.; Benito, M.; Berge, D.; Bernardini, E.; Bernlöhr, K.; Berti, A.; Bertucci, B.; Beshley, V.; Biasuzzi, B.; Biland, A.; Bissaldi, E.; Biteau, J.; Blanch, O.; Blazek, J.; Bocchino, F.; Boisson, C.; Bonneau Arbe…
How consistent are the transcriptome changes associated with cold acclimation in two species of the Drosophila virilis group?
2015
This work was financially support by a Marie Curie Initial Training Network grant, “Understanding the evolutionary origin of biological diversity” (ITN-2008–213780 SPECIATION), grants from the Academy of Finland to A.H. (project 132619) and M.K. (projects 268214 and 272927), a grant from NERC, UK to M.G.R. (grant NE/J020818/1), and NERC, UK PhD studentship to D.J.P. (NE/I528634/1). For many organisms the ability to cold acclimate with the onset of seasonal cold has major implications for their fitness. In insects, where this ability is widespread, the physiological changes associated with increased cold tolerance have been well studied. Despite this, little work has been done to trace chang…
In zwei Welten: ein Lebensbild
1911
Inhalt: Geleitwort./D.M. Kähler/ I. Teil: Licht im Dunkel ; II. Teil: Licht nach dem Dunkel.
Diurnal changes in the perception of emotions in music: Does the time of day matter?
2014
According to the Hindustani music tradition, the ability of a song to induce certain emotions depends on the time of day: playing a song at the right time is said to maximise its emotional effect. The present exploratory study investigated this claim by combining findings in chronobiology, mood research and music perception. It has already been established that some aspects of our mood fluctuations follow a cyclical pattern. Besides, it is a known fact that our current mood influences our perception and assessment of emotions. However, these elements have never been linked together in a study examining the effect of mood cyclicity on perceived emotions in music. To test the hypothesis of a…
Carnosine Inhibits Aβ42Aggregation by Perturbing the H-Bond Network in and around the Central Hydrophobic Cluster
2013
Aggregation of the amyloid-β peptide (Aβ) into fibrillar structures is a hallmark of Alzheimer's disease. Thus, preventing self-assembly of the Aβ peptide is an attractive therapeutic strategy. Here, we used experimental techniques and atomistic simulations to investigate the influence of carnosine, a dipeptide naturally occurring in the brain, on Aβ aggregation. Scanning force microscopy, circular dichroism and thioflavin T fluorescence experiments showed that carnosine does not modify the conformational features of Aβ42 but nonetheless inhibits amyloid growth. Molecular dynamics (MD) simulations indicated that carnosine interacts transiently with monomeric Aβ42 by salt bridges with charge…
Zvaigžņotā Debess: 2000, Rudens (169)
2000
Contents: M.Zepe. Water Steam in the Venus Atmosphere ; B.Sala, L.Kondraševa. Use of Solar Energy ; A.Balklavs. Century Long Astrophysics ; Z.Alksne, A.Alksnis. Plenty of Extrasolar Planets ; Z.Alksne, A.Alksnis. Unexpected Discovery of Spiral Structure in a Dwarf Elliptical Galaxy ; A.Balklavs. Hunting for the Black Holes ; J.Jaunbergs. Private Enterprise on Mir ; T.Czarnik. Surviving Explosive Decompression ; M.Gills. Space Research 40 Years Ago – Chronicle ; M.Krastiņš. Impressions about Rose Center for the Earth and Space ; K.Bērziņš. On Friendly Terms with Cosmology: Basic Principles and Models of the Universe (continuation) ; V.Flerov, A.Cēbers, D.Docenko, V.Kaščejev. Latvia 24th Open…