290 Abstract— This paper aims to simulate dielectric elastomeric (DE) diaphragm for a micropump. First a theoretical study is done to compare the different actuation methods that are currently being used in this field. Then a circular DE diaphragm is modeled for a micropump. The material assumed for the micro diaphragm is 3M’s VHB 4910 (polyacrylic tapes available in the market). The thickness ...

CONJUGATED POLYMER ACTUATORS AND SENSORS: MODELING, CONTROL, AND APPLICATIONS By Yang Fang Conjugated polymers are soft actuation and sensing materials with promising applications in biomedical devices and micromanipulation systems. However, their sophisticated electro-chemo-mechanical dynamics and nonlinear behaviors present significant challenges in such applications. This dissertation is foc...

INTRODUCTION Studies indicate that mechanically ventilated patients develop significant diaphragm muscle weakness, but the etiology of weakness and its clinical impact remain incompletely understood. We assessed diaphragm strength in mechanically ventilated medical ICU patients, correlated the development of diaphragm weakness with multiple clinical parameters, and examined the relationship bet...

Introduction. Recent work revealed the development of marked muscle fiber weakness in the diaphragm, but not in the non-respiratory latissimus dorsi, during thoracic surgery. To disentangle the molecular processes that underlie the development of diaphragm muscle fiber weakness during thoracic surgery, we studied changes in the gene expression profile. Methods. Serial biopsies from the diaphrag...

Diaphragm muscle weakness in patients with chronic obstructive pulmonary disease (COPD) is associated with increased morbidity and mortality. Recent studies indicate that increased contractile protein degradation by the proteasome contributes to diaphragm weakness in patients with COPD. The aim of the present study was to investigate the effect of proteasome inhibition on diaphragm function and...

Esophageal distension and transient lower esophageal sphincter (LES) relaxation (TLESR) are accompanied by simultaneous relaxation of the LES and inhibition of crural diaphragm. Recent studies indicate that baclofen decreases the frequency of TLESR; however, its effect on the crural diaphragm is not known. We evaluated the effects of baclofen on LES relaxation and crural diaphragm inhibition in...

Rat diaphragm muscle has been used almost exclusively for the investigation in vitro of skeletal muscle metabolism. However, the diaphragm is a specialized muscle adapted to constant activity and, with respect to oxygen consumption (1) and oxidative metabolism, seems to occupy an intermediate position between constantly active heart muscle and intermittently active skeletal muscle (2, 3). Histo...

Mechanical ventilation (MV) is a life-saving intervention for patients in respiratory failure. However, prolonged MV causes the rapid development of diaphragm muscle atrophy, and diaphragmatic weakness may contribute to difficult weaning from MV. Therefore, developing a therapeutic countermeasure to protect against MV-induced diaphragmatic atrophy is important. MV-induced diaphragm atrophy is d...

Inspiratory muscle weakness in patients with chronic obstructive pulmonary disease (COPD) is of major clinical relevance; maximum inspiratory pressure generation is an independent determinant of survival in severe COPD. Traditionally, inspiratory muscle weakness has been ascribed to hyperinflation-induced diaphragm shortening. However, more recently, invasive evaluation of diaphragm contractile...