Spatially Controlled Membrane Depositions for Silicon-Based Sensors

The membrane deposition technology on silicon-based transducers constitutes the most delicate part of the miniaturized (bio)chemical sensor fabrication. Membrane adhesion to the transducer, reproducibility of the deposition process and its spatial control are the three most important parameters which determine the sensor performance and lifetime.The fabrication of two sensors is described: 1) a combined pO2, pCO2, pH sensor for which a polyacrylamide gel and a polysiloxane gas-permeable membrane were deposited and patterned at the on-wafer level and 2) a glucose amperometric enzyme electrode where the glucose oxidase was immobilized electrochemically either in a polypyrrole matrix or co-deposited with bovine serum albumin by electrochemically aided adsorption. The optimization of the deposition procedures allowed reproducible devices with reasonable lifetimes to be obtained

A micro gas preconcentrator with improved performance for pollution monitoring and explosives detection

International audienceThis paper presents the optimization of a micro gas preconcentrator based on a micro-channel in porous and non-porous silicon filled with an adequate adsorbent. This micro gas preconcentrator is both applicable in the fields of atmospheric pollution monitoring (Volatil organic compounds—VOCs) and explosives detection (nitroaromatic compounds). Different designs of micro-devices and adsorbent materials have been investigated since these two parameters are of importance in the performances of the micro-device. The optimization of the device and its operation were driven by its future application in outdoor environments. Parameters such as the preconcentration factor, cycle time and the influence of the humidity were considered along the optimization process. As a result of this study, a preconcentrator with a total cycle time of 10 min and the use of single wall carbon nanotubes (SWCNTs) as adsorbent exhibits a good preconcentration factor for VOCs with a limited influence of the humidity. The benefits of using porous silicon to modify the gas desorption kinetics are also investigated

Reinsertion of an inverted osteochondral lesion of the talus: A case report

Osteochondral lesions of the talus (OLTs) occur infrequently and are missed at the initial presentation in up to 67% of cases. Probably more than 1500 OLTs have been reported in published studies, of which, thus far, only 5 cases have been an inverted anterolateral OLT. An anterolateral OLT results from a hypersupination trauma, in which the talar dome is caught behind the fibula. Apparently, if the forces are large enough a " flip of the coin" phenomenon occurs, causing the fragment to invert 180° upside down. We present the case of a young female patient with an inverted OLT that was treated with open reduction and internal fixation using bioabsorbable pins. Follow-up radiographs and computed tomography showed a congruent joint and complete healing of the osteochondral fragment. At the short-term follow-up visit, the functional outcome was promising

Micro gas preconcentrator in porous silicon filled with a carbon absorbent

International audienceThis paper presents the development of a gas preconcentrator based on a micro-channel in porous silicon filled with carbon nanopowders by a micro-fluidic process. The particularity of this device is its applicability in the fields of atmospheric pollution monitoring by targeting VOCS (volatiles organic compounds). Various designs of micro-devices have been investigated and a special focus has been dedicated to the carbon adsorbent. The optimization of the device and its operation were driven by its future application in outdoor environments. The benefits of using porous silicon to ease the fixing of the carbon absorbent in micro-channels and to modify the gas desorption kinetic are also investigated. Results on a device based on a carbon adsorbent powder filled in a porous silicon micro-channel for benzene preconcentration are reported

Observation Versus Embolization in Patients with Blunt Splenic Injury after Trauma: A Propensity Score Analysis

Background: Non-operative management (NOM) is the standard of care in hemodynamically stable patients with blunt splenic injury after trauma. Splenic artery embolization (SAE) is reported to increase observation success rate. Studies demonstrating improved splenic salvage rates with SAE primarily compared SAE with historical controls. The aim of this study was to investigate whether SAE improves success rate compared to observation alone in contemporaneous patients with blunt splenic injury. Methods: We included adult patients with blunt splenic injury admitted to five Level 1 Trauma Centers between January 2009 and December 2012 and selected for NOM. Successful treatment was defined as splenic salvage and no splenic re-intervention. We calculated propensity scores, expressing the probability of undergoing SAE, using multivariable logistic regression and created five strata based on the quintiles of the propensity score distribution. A weighted relative risk (RR) was calculated across strata to express the chances of success with SAE. Results: Two hundred and six patients were included in the study. Treatment was successful in 180 patients: 134/146 (92 %) patients treated with observation and 48/57 (84 %) patients treated with SAE. The weighted RR for success with SAE was 1.17 (0.94-1.45); for complications, the weighted RR was 0.71 (0.41-1.22). The mean number of transfused blood products was 4.4 (SD 9.9) in the observation group versus 9.1 (SD 17.2) in the SAE group. Conclusions: After correction for confounders with propensity score stratification technique, there was no significant difference between embolization and observation alone with regard to successful treatment in patients with blunt splenic injury after trauma