Validation of Math Model Using Porous Media for Determining Alveolar CO 2 in Ventilated Patients.

Objectives: To validate a mathematical model using porous media theory for alveolar CO2 determination in ventilated patients.

Design: Mathematical modeling study with prospective clinical validation to simulate CO2 exchange from bloodstream to airway entrance.

Setting: ICU.

Release of phenolic compounds from fermented cocoa powder during fast heating in a novel hot plate reactor.

This article studies the release of phenolic compounds during cocoa heating under vacuum, N, and air atmospheres, and proposes fast heating (60 °C • s) as a methodology that allows the release of polyphenols from fermented cocoa powder. We aim to demonstrate that gas phase transport is not the only mechanism to extract compounds of interest and that convective-type mechanisms can facilitate the process by reducing their degradation. The oxidation and transport phenomena were evaluated both in the extracted fluid and in the solid sample during the heating process.

Computational model of trachea-alveoli gas movement during spontaneous breathing.

A computational model of the transport of gases involved in spontaneous breathing, from the trachea inlet to the alveoli was developed for healthy patients. Convective and diffusive transport mechanisms were considered simultaneously, using a diffusion coefficient (D) that has considered the four main species of gases present in the exchange carried out by the human lung, nitrogen (N), oxygen (O), carbon dioxide (CO) and water vapor (HO). A Matlab® script was programmed to simulate the trachea-alveolus gas exchange model under three respiratory frequencies: 12, 24 and 40 breaths per minute (BPM), each with three diaphragmatic movements of 2 cm, 4 cm, and 6 cm.

[IgG4 associated nephritis and recurrent hemoptysis: Case report].

IgG4 disease is a multi-systemic condition involving pancreas, salivary glands and lymph nodes. Less frequently, it causes interstitial nephritis and involves the lungs. We report a 58 years old male with a four years history of hemoptysis and renal dysfunction characterized by hematuria and proteinuria, responsive to steroidal therapy.