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Cryo-electron microscopy, atomic force microscopy, and light microscopy investigations provide experimental evidence that amphiphilic emulsion copolymerization particles change their morphology in dependence on concentration. The shape of the particles is spherical at solids content above 1%, but it changes to rod-like, ring-like, and web-like structures at lower concentrations. In addition, the shape and morphology of these particles at low concentrations are not fixed but very flexible and vary with time between spheres, flexible pearlnecklace structures, and stretched rods.
Der Autor versucht mit dieser kurzen Einführung eine Übersicht über den Stand der Forschung zu einem Thema zu geben, das in der Forschung bisher noch nicht ausreichend berücksichtigt wurde: der außerschulischen, privatwirtschaftlich organisierten Zusatzbildung, der sogenannten Shadow Education. Der Fokus der Arbeit richtet sich dabei auf die Länder Japan, welches bereits seit den 1970er Jahren ein System außerschulischer Bildungsinstitutionen besitzt, dessen Einfluss auf den Bildungserwerb junger Menschen so stark ist wie in kaum einem anderen Land, und Deutschland, dessen Schattenbildungs- oder Nachhilfesystem noch keinen derartig starken Einfluss ausübt, jedoch in den vergangenen Jahren steten Zuwachs verzeichnen konnte. Interessierten soll dieser Einblick durch die umfangreiche Bibliographie eine Hilfe bei der Recherche zu diesem Thema bieten.
Both the seat of the German government and the capitol of queer German culture, Berlin has been that spatial nexus of politics, sexuality and gender, work and leisure that has enabled the development of multifarious sexual and gender identities. This has caused celebration and consternation among Germans and foreigners alike. Contemporary studies of urban homosexual space cite an erosion of its 'authenticity' when cities market homosexual space in order to attract tourists. My literary analysis shows that Berlin's homosexual male culture and space had already been subject to commoditisation in the Weimar period (1918-1933), when Berliners discovered marketing potential in the French slight la vice allemand [the German vice] - male homosexuality. This article's examination of Weimar Berlin's spatial binary as 'sexy space' and 'sexualised place' in literature by Klaus Mann and Curt Moreck engages with current debates in leisure studies on the gendering and sexing of geography and leisure. Central to this re-evaluation of leisure and tourism in Weimar Berlin is my discussion of flanerie: the figure of the flaneuse indicates that flanerie was not the lone dominion of heterosexual men. In the context of urban leisure and male homosexuality, I argue that Weimar Berlin consistently and successfully negotiated its dual function of sexy space (allowing self-fashioning for homosexual men in Berlin) and sexualised place (voyeurism and sexual exploration for Berlin's newcomers and tourists).
Background and objective Whether treatment with vitamin D receptor activators contributes to cardiovascular disease in patients with chronic kidney disease is a matter of debate. We studied mechanisms involved in vitamin D-related vascular calcifications in vivo and in vitro.
Methods Aortic calcifications were induced in subtotally nephrectomized (SNX) rats by treatment with a high dose (0.25 mu g/kg per day) of 1,25-dihydroxyvitamin D-3 (calcitriol) given for 6 weeks. Likewise, primary rat vascular smooth muscle cells (VSMCs) were incubated with calcitriol at concentrations ranging from 10(-11) to 10(-7) mol/l. Immunohistochemistry revealed that the aortic expression of osteopontin, osteocalcin and bone sialoprotein was significantly increased in calcitriol-treated SNX rats compared to untreated SNX controls. In addition, aortic expression of the transient receptor potential vanilloid calcium channel 6 (TRPV6) and calbindin D9k was significantly up-regulated by treatment with calcitriol. Furthermore, calcitriol significantly increased expression of the osteogenic transcription factor osterix. In-vitro studies showed similar results, confirming that these effects could be attributed to treatment with calcitriol.
Conclusions High-dose calcitriol treatment induces an osteoblastic phenotype in VSMC both in SNX rats and in vitro, associated with up-regulation of proteins regulating mineralization and calcium transport, and of the osteogenic transcription factor osterix.
1-Oxo-1,3-dithiolane (4) and its cis- and trans-2-methyl (5,6), -4-methyl (7,8) and -5-methyl (9,10) derivatives were prepared by oxidizing the corresponding 1,3-dithiolanes (1-3) with NaIO(4) in water. The oxides were purified and their isomers separated using thin layer chromatography. The structural characterization was carried out with (1)H and (13)C NMR spectroscopy and molecular modelling. The sulfoxides 4-6 and 8-10 attain two S(1) type envelopes (sometimes slightly distorted) the S=O(ax) envelope greatly dominating. Cis-4-methyl-1-oxo-1,3-dithiolane is a special case exhibiting both two closely related S=O(ax) (30 and 27%) as well as S=O(eq) (21 and 22%) forms [S(1) and C(4) envelopes, respectively]. The relative energies of these conformations, the values of (1)H-(1)H coupling constants and (1)H and (13)C chemical shifts were estimated by computational methods and they support well the conclusions based on the experimental data.
1-Oxo-1,3-dithiolane (4) and its cis- andtrans-2-methyl (5,6), -4-methyl (7,8) and -5-methyl (9,10) derivatives were prepared by oxidizing the corresponding 1,3-dithiolanes (1-3) with NaIO4 in water. The oxides were purified and their isomers separated using thin layer chromatography. The structural characterization was carried out with 1H and 13C NMR spectroscopy and molecular modelling. The sulfoxides 4-6 and 8-10 attain two S(1) type envelopes (sometimes slightly distorted) the S=Oax envelope greatly dominating. Cis-4-methyl-1-oxo-1,3-dithiolane is a special case exhibiting both two closely related S=Oax (30 and 27%) as well as S=Oeq (21 and 22%) forms [S(1) and C(4) envelopes, respectively]. The relative energies of these conformations, the values of 1H-1H coupling constants and 1H and 13C chemical shifts were estimated by computational methods and they support well the conclusions based on the experimental data.
Block copolymers of 1H,1H,2H,2H-perfluorodecyl acrylate (AC8) were obtained from ARGET ATRP. To obtain block copolymers of low dispersity the PAC8 block was synthesized in anisole with a CuBr(2)/PMDETA catalyst in the presence of tin(II) 2-ethylhexanoate as a reducing agent. The PAC8 block was subsequently used as macroinitiator for copolymerization with butyl and tert-butyl acrylate carried out in scCO(2). To achieve catalyst solubility in CO(2) two fluorinated ligands were employed. The formation of block copolymers was confirmed by size exclusion chromatography and DSC.
Most 2.5D controlled-source electromagnetic (CSEM) modeling algorithms presented to date explicitly consider only sources that are point dipoles oriented parallel or perpendicular to the direction of constant conductivity. This makes simulations of complex source geometries expensive, requiring separate evaluations of many point dipole fields, and thus limits the practical applicability of such schemes for simulating and interpreting field data. We present a novel 2.5D CSEM modeling scheme that overcomes this limitation and permits efficient simulations of sources with general shape and orientation by evaluating fields for the entire source at once. We accommodate general sources by using a secondary field approach, in which primary fields are computed for the general source and a 1D background conductivity model. To carry out the required Fourier transforms between space and wavenumber domain using the same fast cosine and sine transform filters as in conventional algorithms, we split the primary and secondary fields into their symmetric and antisymmetric parts. For complex 3D source geometries, this approach is significantly more efficient than previous 2.5D algorithms. Our finite-difference algorithm also includes novel approaches for divergence correction at low frequencies and EM field interpolation across conductivity discontinuities. We describe the modeling scheme and demonstrate its accuracy and efficiency by comparisons of 2.5D-simulated data with 1D and 3D results.