A new device for 100 per cent humidification of inspired air

A new humidifier for use during mechanical ventilation in endotracheally intubated patients is described and tested. The humidifier is based on a heat-moisture exchanger, which absorbs the expired heat and moisture and releases it into the inspired air. External heat and water are then added at the patient side of the heat-moisture exchanger, so that the inspired gas should reach 100% humidity (44 mg/l) at 37°C. In bench tests using constant and decelerating inspiratory flow and minute volumes of 3–25 l the device gave an absolute humidity of 41–44 mg/l, and it reduced the amount of water consumed in eight mechanically ventilated patients compared with a conventional active humidifier. During a 24-h test period there was no water condensation in the ventilator tubing with the new device.

On-line microwave-based preconcentration device for inductively coupled plasma atomic emission spectrometry: Application to the elemental analysis of spirit samples

A microwave-based thermal nebulizer (MWTN) has been employed for the first time as on-line preconcentration device in inductively coupled plasma atomic emission spectrometry (ICP-AES). By the appropriate selection of the experimental conditions, the MWTN could be either operated as a conventional thermal nebulizer or as on-line analyte preconcentration and nebulization device. Thus, when operating at microwave power values above 100 W and highly concentrated alcohol solutions, the amount of energy per solvent mass liquid unit (EMR) is high enough to completely evaporate the solvent inside the system and, as a consequence, the analyte is deposited (and then preconcentrated) on the inner walls of the MWTN capillary. When reducing the EMR to the appropriate value (e.g., by reducing the microwave power at a constant sample uptake rate) the retained analyte is swept along by the liquid-gas stream and an analyte-enriched aerosol is generated and next introduced into the plasma cell. Emission signals obtained with the MWTN operating in preconcentration-nebulization mode improved when increasing preconcentration time and sample uptake rate as well as when decreasing the nozzle inner diameter. When running with pure ethanol solution at its optimum experimental conditions, the MWTN in preconcentration-nebulization mode afforded limits of detection up to one order of magnitude lowers than those obtained operating the MWTN exclusively as a nebulizer. To validate the method, the multi-element analysis (i.e. Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Pb and Zn) of different commercial spirit samples in ICP-AES has been performed. Analyte recoveries for all the elements studied ranged between 93% and 107% and the dynamic linear range covered up to 4 orders of magnitude (i.e. from 0.1 to 1000 μg L−1). In these analysis, both MWTN operating modes afforded similar results. Nevertheless, the preconcentration-nebulization mode permits to determine a higher number of analytes due to its higher detection capabilities.

Development of a magnetic resonance compatible wrist device for the analysis of movement encoding in the brain

Tese de mestrado integrado em Engenharia Biomédica e Biofísica, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2016

HTML5, Javascript and modern browser technologies: toward a web based framework for device fingerprinting

Mentre navighiamo siamo veramente certi che i nostri dati e la nostra privacy siano al sicuro? I browser e le tecnologie di cui fanno uso possono rivelare una miriade di informazioni. Al crescere delle informazioni reperibili, si inizia a superare una massa critica che può permettere l'identificazione. Il device fingerprinting è proprio il rilevamento di questa tipologia di dati. HTML5 e le nuove API che esso mette a disposizione aumentano a dismisura le modalità per fare fingerprinting. Durante lo sviluppo della presente tesi è stato realizzato un framework molto potente che verrà mostrato nel dettaglio. Come a seguito di un disastro aereo, l'ingegneria aeronautica si mette all'opera per scovare i punti deboli allo scopo di rendere più robusti gli aerei di nuova generazione, noi con la presente tesi vogliamo dare il nostro contributo al miglioramento del web del futuro. Affinchè la nostra privacy sia veramente nelle nostre mani e possiamo essere artefici del nostro domani.

A synthetic biology-based device prevents liver injury in mice

BACKGROUND & AIMS The liver performs a panoply of complex activities coordinating metabolic, immunologic and detoxification processes. Despite the liver's robustness and unique self-regeneration capacity, viral infection, autoimmune disorders, fatty liver disease, alcohol abuse and drug-induced hepatotoxicity contribute to the increasing prevalence of liver failure. Liver injuries impair the clearance of bile acids from the hepatic portal vein which leads to their spill over into the peripheral circulation where they activate the G-protein-coupled bile acid receptor TGR5 to initiate a variety of hepatoprotective processes. METHODS By functionally linking activation of ectopically expressed TGR5 to an artificial promoter controlling transcription of the hepatocyte growth factor (HGF), we created a closed-loop synthetic signalling network that coordinated liver injury-associated serum bile acid levels to expression of HGF in a self-sufficient, reversible and dose-dependent manner. RESULTS After implantation of genetically engineered human cells inside auto-vascularizing, immunoprotective and clinically validated alginate-poly-(L-lysine)-alginate beads into mice, the liver-protection device detected pathologic serum bile acid levels and produced therapeutic HGF levels that protected the animals from acute drug-induced liver failure. CONCLUSIONS Genetically engineered cells containing theranostic gene circuits that dynamically interface with host metabolism may provide novel opportunities for preventive, acute and chronic healthcare. LAY SUMMARY Liver diseases leading to organ failure may go unnoticed as they do not trigger any symptoms or significant discomfort. We have designed a synthetic gene circuit that senses excessive bile acid levels associated with liver injuries and automatically produces a therapeutic protein in response. When integrated into mammalian cells and implanted into mice, the circuit detects the onset of liver injuries and coordinates the production of a protein pharmaceutical which prevents liver damage.

Short structured feedback training is equivalent to a mechanical feedback device in two-rescuer BLS: a randomised simulation study.

BACKGROUND Resuscitation guidelines encourage the use of cardiopulmonary resuscitation (CPR) feedback devices implying better outcomes after sudden cardiac arrest. Whether effective continuous feedback could also be given verbally by a second rescuer ("human feedback") has not been investigated yet. We, therefore, compared the effect of human feedback to a CPR feedback device. METHODS In an open, prospective, randomised, controlled trial, we compared CPR performance of three groups of medical students in a two-rescuer scenario. Group "sCPR" was taught standard BLS without continuous feedback, serving as control. Group "mfCPR" was taught BLS with mechanical audio-visual feedback (HeartStart MRx with Q-CPR-Technology™). Group "hfCPR" was taught standard BLS with human feedback. Afterwards, 326 medical students performed two-rescuer BLS on a manikin for 8 min. CPR quality parameters, such as "effective compression ratio" (ECR: compressions with correct hand position, depth and complete decompression multiplied by flow-time fraction), and other compression, ventilation and time-related parameters were assessed for all groups. RESULTS ECR was comparable between the hfCPR and the mfCPR group (0.33 vs. 0.35, p = 0.435). The hfCPR group needed less time until starting chest compressions (2 vs. 8 s, p < 0.001) and showed fewer incorrect decompressions (26 vs. 33 %, p = 0.044). On the other hand, absolute hands-off time was higher in the hfCPR group (67 vs. 60 s, p = 0.021). CONCLUSIONS The quality of CPR with human feedback or by using a mechanical audio-visual feedback device was similar. Further studies should investigate whether extended human feedback training could further increase CPR quality at comparable costs for training.

Effects of exercise training on intrauterine growth restriction in an animal model

Résumé Selon l'OMS, la retard de croissance intra-utérine (RCIU; 10% en dessous du poids normal pendant la grossesse) affecte 5-10% des grossesses et est une cause principale de la morbidité et de la mortalité périnatales. Dans notre étude précédente sur un modèle de souris transgénique de prééclampsie (R+A+), nous avons constaté que l’entraînement physique (ExT) avant et pendant la grossesse réduisait la pression artérielle maternelle et empêchait la RCIU en améliorant le développement placentaire. Dans le cadre de mon projet, nous avons confirmé les bénifices de l’ExT dans un modèle de RCIU (souris déficiente en p57Kip2 (p57-/+). Ainsi, nous avons observé la présence de RCIU, d’une masse placentaire réduite, d’une augmentation de la pathologie placentaire ainsi qu’une plus petite taille des portées chez les souris p57-/+ sédentaire. L’ExT prévient la RCIU ainsi que tous les paramètres mentionnés ci-haut. Nous avons observé que l'expression du facteur de croissance de l’endothélium vasculaire, un régulateur clé de l'angiogenèse lors de la croissance placentaire, était réduite dans le placenta des souris p57-/+ et normalisée par l’ExT. Nous avons également trouvé que l'expression en ARN dans le placenta de 2 facteurs inflammatoires (interleukine-1β et MCP-1) était augmenté chez les souris sédentaires p57-/+ alors que ceci n’était pas présent chez les souris entraînées, ce qui suggère que l'inflammation placentaire peut contribuer à la pathologie placentaire. Toutefois, contrairement aux souris R+A+, le système rénine-angiotensine placentaire chez les souris p57-/+ était normale et aucun effet de l’ExT a été observé. Ces résultats suggèrent que l’ExT prévient la RCIU en normalisant la pathologie placentaire, l’angiogenèse et l’inflammation placentaire.