L'Afrique des pouvoirs et la démocratie

Gruénais Marc-Eric, Schmitz Jean. L'Afrique des pouvoirs et la démocratie. In: Cahiers d'études africaines, vol. 35, n°137, 1995. La démocratie déclinée. pp. 7-17

Instandsetzung von Schleusenanlagen unter laufendem Betrieb – Anwendung Modulbaukasten

BAWBrief 02/202

Current Concepts on 6-sulfo LacNAc Expressing Monocytes (slanMo)

The human mononuclear phagocytes system consists of dendritic cells (DCs), monocytes, and macrophages having different functions in bridging innate and adaptive immunity. Among the heterogeneous population of monocytes the cell surface marker slan (6-sulfo LacNAc) identifies a specific subset of human CD14− CD16+ non-classical monocytes, called slan+ monocytes (slanMo). In this review we discuss the identity and functions of slanMo, their contributions to immune surveillance by pro-inflammatory cytokine production, and cross talk with T cells and NK cells. We also consider the role of slanMo in the regulation of chronic inflammatory diseases and cancer. Finally, we highlight unresolved questions that should be the focus of future research

Tumor Evasion from T Cell Surveillance

An intact immune system is essential to prevent the development and progression of neoplastic cells in a process termed immune surveillance. During this process the innate and the adaptive immune systems closely cooperate and especially T cells play an important role to detect and eliminate tumor cells. Due to the mechanism of central tolerance the frequency of T cells displaying appropriate arranged tumor-peptide-specific-T-cell receptors is very low and their activation by professional antigen-presenting cells, such as dendritic cells, is frequently hampered by insufficient costimulation resulting in peripheral tolerance. In addition, inhibitory immune circuits can impair an efficient antitumoral response of reactive T cells. It also has been demonstrated that large tumor burden can promote a state of immunosuppression that in turn can facilitate neoplastic progression. Moreover, tumor cells, which mostly are genetically instable, can gain rescue mechanisms which further impair immune surveillance by T cells. Herein, we summarize the data on how tumor cells evade T-cell immune surveillance with the focus on solid tumors and describe approaches to improve anticancer capacity of T cells

Raman spectroscopy as probe of nanometer-scale strain variations in graphene

Confocal Raman spectroscopy is a versatile, non-invasive investigation tool and a major workhorse for graphene characterization. Here we show that the experimentally observed Raman 2D line width is a measure of nanometer-scale strain variations in graphene. By investigating the relation between the G and 2D line at high magnetic fields we find that the 2D line width contains valuable information on nanometer-scale flatness and lattice deformations of graphene, making it a good quantity for classifying the structural quality of graphene even at zero magnetic field.Comment: 7 pages, 4 figure

Power Hardware-in-the-Loop Test Bench for Permanent Magnet Synchronous Machines based on a Parallel Hybrid Converter

This paper presents a Power Hardware-in-the-Loop (PHIL) emulation test bench for emulating highly utilized perma-nent magnet synchronous machines (PMSM). The output stage of the PHIL is a Cascaded H-bridge based Parallel Hybrid Converter (PHC) with a 17-level output voltage and an effective switching frequency of 1 MHz. The nonlinear machine is emu-lated with a sampling frequency of 5 MHz and is implemented on a field programmable gate array (FPGA) using Matlab/Simulink\u27s HDL Coder. For this purpose, the time-discretized model equations of a PMSM and the PHIL test bench are derived and their mapping into an HDL code-generable and fully fixed-point transformed model in Simulink is described. To enable the high model sampling rate of 5 MHz, it is optimized for a low clock cycle count and the nonlinear relations between the machine currents and flux linkages are stored in lookup tables (LUT). The measurements are carried out in steady-state operation as well as for highly dynamic current and rotor speed steps. They demonstrate the excellent performance of the presented PHIL test bench, which even perfectly reproduces the current ripple of the modeled PMSM

Hardware-in-the-Loop Setup for a Modular Multilevel Converter with Integrated Batteries

A hardware-in-the-loop setup to emulate a modular multilevel converter (MMC) with batteries integrated in its submodules is presented. It allows the testing of control methods without a real converter. A state-space MMC model is introduced, extended by RC battery models and implemented on an FPGA. The scalability of battery models for converters with large numbers of submodules is shown. The emulation closes the loop for a combined MMC-controller and battery management algorithm under test, running on an ARM processor. Given the modular approach, the level of detail for power electronics, batteries and control schemes can be adapted independently