Objectives: Investigate the acute effects of non-invasive ventilation (NIV) on cerebral blood flow (CBF) and on cognitive functions in COPD.
Methods: Nine non-hypercapnic stable COPD and twelve healthy controls were enrolled. CBF (transcranial Doppler), cognitive tests and cardiorespiratory response were performed at baseline, during one hour of NIV and after 30 min.
We investigate high brightness pumping of a multi-kilowatt Yb fiber amplifier in a bi-directional pumping configuration. Each pump outputs 2 kW in a 200 μm, 0.2 NA multimode fiber.
View Article and Find Full Text PDFA theoretical and experimental investigation of the transmission of solid-core photonic crystal fibers (PCFs) filled with nonlinear absorbers shows a sharp change in the threshold for optical limiting and in leakage loss as the refractive index of the material in the holes approaches that of the glass matrix. Theoretical calculations of the mode profiles and leakage loss of the PCF are in agreement with experimental results and indicate that the change in limiting response is due to the interaction of the evanescent field of the guided mode with the nonlinear absorbers in the holes.
View Article and Find Full Text PDFBackground: Several complex mechanisms including biological, psychological and social factors may contribute to the development of bodily symptoms. Affective temperaments may represent heritable subclinical manifestations of mood disorders, and the concept of ego defense mechanisms has also provided a model for the comprehension of psychopathology. The relationship between affective temperaments, defensive functioning and somatic symptom severity remains unknown.
View Article and Find Full Text PDFWe demonstrate the use of digital coherent superposition to improve the performance of space-division-multiplexed (SDM) 676-Gb/s OFDM-16QAM superchannels, achieving ~4 dB improvement in OSNR by using two SDM copies and 1075-km (14 x 76.8 km) transmission over a seven-core-fiber with an effective aggregate spectral efficiency of 23.7 b/s/Hz.
View Article and Find Full Text PDF