Controlling front-end electronics boards using commercial solutions

LHCb is a dedicated B-physics experiment under construction at CERN's large hadron collider (LHC) accelerator. This paper will describe the novel approach LHCb is taking toward controlling and monitoring of electronics boards. Instead of using the bus in a crate to exercise control over the boards, we use credit-card sized personal computers (CCPCs) connected via Ethernet to cheap control PCs. The CCPCs will provide a simple parallel, I2C, and JTAG buses toward the electronics board. Each board will be equipped with a CCPC and, hence, will be completely independently controlled. The advantages of this scheme versus the traditional bus-based scheme will be described. Also, the integration of the controls of the electronics boards into a commercial supervisory control and data acquisition (SCADA) system will be shown. (5 refs)

Confining Trypanosoma brucei in emulsion droplets reveals population variabilities in division rates and improves in vitro cultivation

Trypanosome parasites are infecting mammals in Sub-Saharan Africa and are transmitted between hosts through bites of the tsetse fly. The transmission from the insect vector to the mammal host causes a number of metabolic and physiological changes. A fraction of the population continuously adapt to the immune system of the host, indicating heterogeneity at the population level. Yet, the cell to cell variability in populations is mostly unknown. We develop here an analytical method for quantitative measurements at the single cell level based on encapsulation and cultivation of single-cell Trypanosoma brucei in emulsion droplets. We first show that mammalian stage trypanosomes survive for several hours to days in droplets, with an influence of droplet size on both survival and growth. We unravel various growth patterns within a population and find that droplet cultivation of trypanosomes results in 10-fold higher cell densities of the highest dividing cell variants compared to standard cultivation techniques. Some variants reach final cell titers in droplets closer to what is observed in nature than standard culture, of practical interest for cell production. Droplet microfluidics is therefore a promising tool for trypanosome cultivation and analysis with further potential for high-throughput single cell trypanosome analysis

Paper-based enzymatic microfluidic fuel cell: From a two-stream flow device to a single-stream lateral flow strip

This work presents a first approach towards the development of a cost-effective enzymatic paper-based glucose/O2 microfluidic fuel cell in which fluid transport is based on capillary action. A first fuel cell configuration consists of a Y-shaped paper device with the fuel and the oxidant flowing in parallel over carbon paper electrodes modified with bioelectrocatalytic enzymes. The anode consists of a ferrocenium-based polyethyleneimine polymer linked to glucose oxidase (GOx/Fc-C6-LPEI), while the cathode contains a mixture of laccase, anthracene-modified multiwall carbon nanotubes, and tetrabutylammonium bromide-modified Nafion (MWCNTs/laccase/TBAB-Nafion). Subsequently, the Y-shaped configuration is improved to use a single solution containing both, the anolyte and the catholyte. Thus, the electrolytes pHs of the fuel and the oxidant solutions are adapted to an intermediate pH of 5.5. Finally, the fuel cell is run with this single solution obtaining a maximum open circuit of 0.55 ± 0.04 V and a maximum current and power density of 225 ± 17 μA cm−2 and 24 ± 5 μW cm−2, respectively. Hence, a power source closer to a commercial application (similar to conventional lateral flow test strips) is developed and successfully operated. This system can be used to supply the energy required to power microelectronics demanding low power consumption.F. Javier del Campo acknowledges funding from the Spanish Ministry of Economy through the DADDi2 project (TEC2013-48506-C3). Juan Pablo Esquivel would like to thank the support from Marie Curie International Outgoing Fellowship (APPOCS-328144) within the 7th European Community Framework Programme. Shelley D. Minteer and Fabien Giroud would like to thank the National Science Foundation (CHE-1057597) for funding. Neus Sabaté acknowledges funding from the European H2020 Framework Programme (Grant Agreement 648518 - SUPERCELL - ERC 2014 CoG).Peer reviewe

Planck pre-launch status : The Planck mission

Peer reviewe

Etudes des désintégrations de mésons beaux avec photons convertis dans l'expérience LHCbLHC_b

The LHCb experiment studies CP violation in B meson decays and will take data in 2007. Analysis strategy are studied on simulations. In this development, I worked on many fields, and essentially in: - converted photons reconstruction: the charge deposited by electrons and positrons produced by converted photons can be seen and allow to detect them. The low rate of conversion is of course to consider and the use of converted photons is advantageous only because of their good momentum measurements. - decay channels with converted photon selection: the good momentum resolution allows to select different channels, among which: B0 -> K* gamma, B0 -> pi- pi+ pi0 and B0 -> pi0 pi0. Despite low branching ratios, I show that these modes can be studied. The classical method with photons detected by the electromagnetical calorimeter being difficult, the use of converted photons will be an advantage for LHCb

Etude des désintégrations de mésons beaux avec photons convertis dans l'expérience LHCb

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Mission d'etudes au Yémen.

Donated by Klaus KreiserReprinted from : La Géographie 28, 1913

Directed evolution and enzymatic biofuel cells,study of CotA laccase and its optimization by directed evolution using droplet based microfluidic

Les biopiles enzymatiques ont vu le jour pour développer des sources miniatures d'électricité renouvelable. Cette technologie naissante est cependant encore limitée en termes de puissance ou de durée de vie. Bien qu encore peu employée, une stratégie pourEnzymatic biofuel cells have been recently developed to create miniature renewable electricity sources. However, this new technology is still limited in terms of power and lifetime compared to classical fuel cells. Although it has been rarely used yet, o