CpCo(III) Precatalysts for [2+2+2] Cycloadditions

Catalysts applied in cobalt-catalyzed cyclotrimerizations reactions in general rely on the use of Co(I) precatalysts or the in situ generation of Co(I) catalysts from Co(II) sources by reduction in the presence of steering ligands, often by addition of less noble metals. In this paper, we report the synthesis and properties of novel stable CpCo(III) complexes as precatalysts and their exemplary evaluation for application in catalytic [2+2+2] cycloadditions. The role of phosphite neutral ligands, as well as iodide and cyanide as anionic ligands, on the reactivity of the complexes was evaluated. A modified one-pot approach to the synthesis of Cp ring-functionalized Cp’Co(III) complexes was developed. The investigations demonstrated that CpCo(III) complexes can be directly applied as catalysts in catalytic cyclotrimerizations of triynes without reducing agents as additives. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

Measurement and Scale Analysis of Convective Transport over Heterogeneous Terrain

Meso-scale structures (MS) are supposed to be a major reason for the energy balance closure (EBC) problem of eddy-covariance measurments. This is assessed with Doppler lidar, tower and aircraft measurements. The lidar data provide evidence for MS in the surface layer, the airborne data show that MS contribute to the turbulent heat fluxes. The friction velocity and the gradients of temperature and moisture are promising variables for parameterizing the EBC

Independent Performing Arts in Europe: Institutional Consolidation and Precariousness of an Emerging Field

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Kyrle Disease and Acquired Perforating Collagenosis Secondary to Chronic Renal Failure and Diabetes Mellitus

A 59-year-old man with chronic renal failure and diabetes mellitus presented with pruritic crusted lesions which histologically were perforating disorders, showing features of both Kyrle disease and acquired perforating collagenosis. The mechanisms of transepidermal elimination and the classification of perforating disorders are briefly discussed. Additionally, we question the concept of perforation, as epidermal damage and exposure of subepidermal substances may artificially present as perforation

Spin currents in diluted magnetic semiconductors (extended version)

Spin currents resulting in the zero-bias spin separation have been observed in unbiased diluted magnetic semiconductor structures (Cd,Mn)Te/(Cd,Mg)Te. The pure spin current generated due to the electron gas heating by terahertz radiation is converted into a net electric current by application of an external magnetic field. We demonstrate that polarization of the magnetic ion system enhances drastically the conversion due to the spin-dependent scattering by localized Mn(2+) ions and the giant Zeeman splitting.Comment: 6 pages, 4 figure

Validez de la ordenanza 13 de 1947 del departamento de Cundinamarca a la luz de la constitución política de 1991

Mediante el presente trabajo, se quiere analizar las soluciones jurídicas que podemos utilizar cuando estamos frente a un vacío normativo en la aplicación de normas laborales para los servidores públicos, con el fin de salvaguardar los derechos que han sido adquiridos y que están siendo arbitrariamente negados por el ente estatal. Se pretende demostrar si las normas creadoras de emolumentos salariales para empleados del Estado, expedidas por entidades territoriales con anterioridad de la Constitución Política de 1991 son aplicables, lo anterior teniendo en cuenta que el Congreso de la Republica en función concurrente con el Gobierno Nacional, son las únicas instituciones facultadas legal y constitucionalmente para la regulación de asuntos salariales respecto a los empleados púbicos. Queremos exponer las interpretaciones vagas y erradas que se le están dando a la aplicación del reconocimiento del 20% de sobresueldo que contempla la Ordenanza 13 de 1947 para los empleados y obreros del Departamento de Cundinamarca, debido al desconocimiento que se viene presentando tanto por los operadores jurídicos como por los funcionarios del ente territorial. Este trabajo, va dirigido a docentes y empleados del Departamento de Cundinamarca, profesionales del derecho, jueces y todas aquellas personas interesadas en el tema, ya que servirá de guía en el evento de existir duda en la reclamación y aplicación del derecho que está contemplado en la ordenanza 13 del año 47

Synthesis and Characterization of Ceramide-Containing Liposomes as Membrane Models for Different T Cell Subpopulations

A fine balance of regulatory (Treg) and conventional CD4+ T cells (Tconv) is required to prevent harmful immune responses, while at the same time ensuring the development of protective immunity against pathogens. As for many cellular processes, sphingolipid metabolism also crucially modulates the Treg/Tconv balance. However, our understanding of how sphingolipid metabolism is involved in T cell biology is still evolving and a better characterization of the tools at hand is required to advance the field. Therefore, we established a reductionist liposomal membrane model system to imitate the plasma membrane of mouse Treg and Tconv with regards to their ceramide content. We found that the capacity of membranes to incorporate externally added azide-functionalized ceramide positively correlated with the ceramide content of the liposomes. Moreover, we studied the impact of the different liposomal preparations on primary mouse splenocytes in vitro. The addition of liposomes to resting, but not activated, splenocytes maintained viability with liposomes containing high amounts of C16-ceramide being most efficient. Our data thus suggest that differences in ceramide post-incorporation into Treg and Tconv reflect differences in the ceramide content of cellular membranes

Implementación de soluciones específicas mediante Nethserver

En el desarrollo del presente artículo se documentarán los resultados de la puesta en marcha de un servidor en ambiente virtualizado de la distribución GNU/Linux NethServer 7.9.2009, esto como solución propuesta para la implementación de servicios de infraestructura IT. Los servicios que se implementaran son DHCP Server, DNS Server, Controlador de Dominio, Proxy, Cortafuegos, File Server, Print Server y VPN, lo anterior como solución a la problemática previamente planteada.In the development of this article, the results of the implementation of a server in a virtualized environment of the GNU/Linux NethServer 7.9.2009 distribution will be documented, this as a proposed solution for the implementation of IT infrastructure services. The services that will be implemented are DHCP Server, DNS Server, Domain Controller, Proxy, Firewall, File Server, Print Server and VPN, the above as a solution to the previously raised problem

Little Things

We present LITTLE THINGS (Local Irregulars That Trace Luminosity Extremes, The HI Nearby Galaxy Survey) that is aimed at determining what drives star formation in dwarf galaxies. This is a multi-wavelength survey of 37 Dwarf Irregular and 4 Blue Compact Dwarf galaxies that is centered around HI-line data obtained with the National Radio Astronomy Observatory (NRAO) Very Large Array (VLA). The HI-line data are characterized by high sensitivity (less than 1.1 mJy/beam per channel), high spectral resolution (less than or equal to 2.6 km/s), and high angular resolution (~6 arcseconds. The LITTLE THINGS sample contains dwarf galaxies that are relatively nearby (less than or equal to 10.3 Mpc; 6 arcseconds is less than or equal to 300 pc), that were known to contain atomic hydrogen, the fuel for star formation, and that cover a large range in dwarf galactic properties. We describe our VLA data acquisition, calibration, and mapping procedures, as well as HI map characteristics, and show channel maps, moment maps, velocity-flux profiles, and surface gas density profiles. In addition to the HI data we have GALEX UV and ground-based UBV and Halpha images for most of the galaxies, and JHK images for some. Spitzer mid-IR images are available for many of the galaxies as well. These data sets are available on-line.Comment: In press in A