CT is a powerful method for noninvasive assessment of the lung. Advancements to CT technology have guided the high-resolution structural and functional assessment of lung diseases. This has helped make the transition from characterizing the severity of lung disease to novel phenotyping of disease subtypes. Chronic obstructive pulmonary disease (COPD) is a spectrum of inflammatory lung disease affecting lung parenchyma, airways, and the pulmonary and systemic vasculature. Quantitative CT-based measures have largely focused on quantifying the extent of airway and parenchymal damage with disease. Recently perfusion CT method has been used to assess the pulmonary vascular bed. This technique was used to demonstrate a vascular etiology of smoking-associated centriacinar emphysema (CAE), a subtype of the COPD spectrum. However, technical challenges have limited the transition of this CT method to clinical studies to assess pulmonary vascular physiology. In this thesis, we introduce dual energy CT-perfused blood volume (DECT-PBV) as a novel image-based biomarker to assess peripheral pulmonary vascular dysfunction. Using this technique, we show that smoking-associated pulmonary perfusion heterogeneity, a marker of abnormal blood flow is a reversible process, in the midst of smoking-associated lung inflammation, and not a product of advanced lung disease. We demonstrate, via regional PBV measures and structural measures of the central pulmonary vessels, that the reversibility of pulmonary perfusion heterogeneity is a direct result of increased peripheral (downstream) parenchymal perfusion. We validate our quantitative imaging approach in a unique cohort of early CAE-susceptible smokers using a pharmaceutical intervention to dilate the pulmonary parenchymal vascular bed. The validated DECT approach and our novel DECT imaging findings extend our characterization of the vascular phenotype in inflammatory lung disease and provide a framework for future quantitative imaging studies of the lung to assess early intervention targeted to pulmonary vessels.

The current work investigated the stimulation induced spatial response of the cerebral microvascular network by reconstruction of the 3D microvascular morphology from in vivo two photon fluorescence microscopy (2PFM) volumes using an automated, model based tracking algorithm. In vivo 2PFM imaging of the vasculature in the forelimb representation of the primary somatosensory cortex of alpha-chloralose anesthetized rats was achieved via implantation of a closed cranial window, and intravascular injection of fluorescent dextran. The dilatory and constrictory responses of the cerebral microvascular network to functional stimulation were heterogeneous and depended on resting vascular radius and response latency. Capillaries experienced large relative dilations and constrictions, but the larger vessel absolute volume changes dominated the overall network cerebral blood volume change.

The current work investigated the stimulation induced spatial response of the cerebral microvascular network by reconstruction of the 3D microvascular morphology from in vivo two photon fluorescence microscopy (2PFM) volumes using an automated, model based tracking algorithm. In vivo 2PFM imaging of the vasculature in the forelimb representation of the primary somatosensory cortex of alpha-chloralose anesthetized rats was achieved via implantation of a closed cranial window, and intravascular injection of fluorescent dextran. The dilatory and constrictory responses of the cerebral microvascular network to functional stimulation were heterogeneous and depended on resting vascular radius and response latency. Capillaries experienced large relative dilations and constrictions, but the larger vessel absolute volume changes dominated the overall network cerebral blood volume change.

Effective game music is typically adaptive, interactive, or both. Changes in game music are usually influenced by the current state of the game or the actions of the player. To provide another dimension of interactivity, it would be useful to know the affective state of the human player. Biosignals are continuous signals generated by a person that can be measured over time, and have been shown to reflect affective state. This project demonstrates that control signals can be gathered from the player and mapped to musical parameters. Using a heart rate sensor and galvanic skin response sensor built from open source designs, we have used biosignals to control music playback while playing four games from different genres. A system for controlling game music with biosignals is computationally cheap, and can provide data that is useful to other game systems. The prototype developed for this project is basic, but with further research and development, we believe such a system will greatly improve the immersive experience of video games by involving the player on a new level. / text

1) Both the partially euryhaline Scyliorhinus canicula and the fully euryhaline Carcharhinus leucas significantly modify plasma concentrations of urea and chloride (Cl-) (and sodium (Na+)) in response to changes in environmental salinity, in order to maintain overall plasma osmolality slightly hyper- or isosmotic to the environment. C. leucas has a greater capacity for urea retention in dilute environments. In S. canicula all of these changes occur within 12 hours of transfer, with the notable exception of increasing plasma urea in response to acute transfer to elevated salinity. 2) A new technique, 51Cr-labelled erythrocytes, was developed to assess blood volume in elasmobranch fish. S. canicula displays significant haemodilution and concentration during chronic acclimation to decreased and increased environmental salinity respectively. Significant changes in blood volume were seen within 6 hours of acute salinity transfer. 3) In vivo secretion rates were measured in the rectal gland of S. canicula during both chronic and acute salinity transfer. Significant changes in Cl- clearance occur during acute transfer, as plasma Na+ and Cl- levels are modified, but do not persist in chronically acclimated animals. This is achieved through modifications in the volume and Cl- concentration of the secretory fluid. 4) C. leucas is able to significantly alter the abundance and/or recruitment of Na+, K+-ATPase in both the rectal gland and the kidney during chronic acclimation to salinity transfer. This is presumably in response to increased requirements for NaCl secretion in SW and osmolyte retention in FW respectively. S. canicula do not significantly alter abundance and/or recruitment of Na+, K+-ATPase in the principle osmoregulatory organs following chronic acclimation to salinity transfer. 5) Chronically SW acclimated C. leucas modify the proportion of ouabain-sensitive oxygen consumption in the tissues of the rectal gland in response to the secretory endocrine stimulus C-type natriuretic peptide (CNP). No such modification occurred in the rectal glands of FW acclimated C. leucas. This represents a change in the sensitivity and response to endocrine control factors during chronic acclimation to salinity transfer in this species. No such modification was seen the in the proportion of ouabain-sensitive oxygen consumption in the rectal glands of chronically acclimated S. canicula in response to CNP. These results were discussed in relation to the capacity for modification of osmoregulatory organs in partially and fully euryhaline elasmobranchs.

Diss. (sammanfattning) Uppsala : Univ., 2003. / Härtill 5 uppsatser.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Bilagan utgöres av sammanfattnig på svenska med titeln: Fysiologiskt svar på arbete hos varmblodiga travhästar i relation till total blodvolym. Härtill 5 uppsatser.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2006. / Härtill 4 uppsatser.

Thesis (M.Sc. (Physiology))--Mahidol University, 1978.

Recording and monitoring vital signs is an essential aspect of home-based healthcare. Using contact sensors to record physiological signals can cause discomfort to patients, especially after prolonged use. Hence, remote physiological measurement approaches have attracted considerable attention as they do not require physical contact with the patient’s skin. Several studies proposed techniques to measure Heart Rate (HR) and Heart Rate Variability (HRV) by detecting the Blood Volume Pulse (BVP) from human facial video recordings while the subject is in a resting condition. In this thesis, we focus on the measurement of HR. We adopt an algorithm that uses the Independent Component Analysis (ICA) to separate the source (physiological) signal from noise in the RGB channels of a facial video. We generalize existing methods to support subject movement during video recording. When a subject is moving, the face may be turned away from the camera. We utilize multiple cameras to enable the algorithm to monitor the vital sign continuously, even if the subject leaves the frame or turns away from a subset of the system’s cameras. Furthermore, we improve the accuracy of existing methods by implementing a light equalization scheme to reduce the effect of shadows and unequal facial light on the HR estimation, a machine learning method to select the most accurate channel outputted by the ICA module, and a regression technique to adjust the initial HR estimate. We systematically test our method on eleven subjects using four cameras. The proposed method decreases the RMSE by 27% compared to the state of the art in the rest condition. When the subject is in motion, the proposed method achieves a RMSE of 1.12 bpm using a single camera and RMSE of 0.96 bpm using multiple camera.