Дисертації з теми "Respiratory signal processing"
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Cherif, Safa. "Effective signal processing methods for robust respiratory rate estimation from photoplethysmography signal." Thesis, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2018. http://www.theses.fr/2018IMTA0094/document.
Повний текст джерелаOne promising area of research in clinical routine involves using photoplethysmography (PPG) for monitoring respiratory activities. PPG is an optical signal acquired from oximeters, whose principal use consists in measuring oxygen saturation. Despite its simplicity of use, the deployment of this technique is still limited because of the signal sensitivity to distortions and the non-reproducibility between subjects, but also for the same subject, due to age and health conditions. The main aim of this work is to develop robust and universal methods for estimating accurate respiratory rate regardless of the intra- and inter-individual variability that affects PPG features. For this purpose, firstly, an adaptive artefact detection method based on template matching and decision by Random Distortion Testing is introduced for detecting PPG pulses with artefacts. Secondly, an analysis of several spectral methods for Respiratory Rate (RR) estimation on two different databases, with different age ranges and different respiratory modes, is proposed. Thirdly, a Spectral Respiratory Quality Index (SRQI) is attributed to respiratory rate estimates, in order that the clinician may select only RR values with a large confidence scale. Promising results are found for two different databases
Antonsson, Per, and Jesper Johansson. "Measuring Respiratory Frequency Using Optronics and Computer Vision." Thesis, Linköpings universitet, Datorseende, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-176354.
Повний текст джерелаMotamedi, Fakhr Shayan. "Application of signal processing to respiratory cycle related EEG change (RCREC) in children." Thesis, University of Southampton, 2014. https://eprints.soton.ac.uk/363767/.
Повний текст джерелаRaoof, Kosai. "Traitement du signal électromyographique des muscles respiratoires et estimation des paramètres en temps réel." Grenoble 1, 1993. http://www.theses.fr/1993GRE10013.
Повний текст джерелаAjčević, Miloš. "Personalized setup of high frequency percussive ventilator by estimation of respiratory system viscoelastic parameters." Doctoral thesis, Università degli studi di Trieste, 2015. http://hdl.handle.net/10077/10976.
Повний текст джерелаHigh Frequency Percussive Ventilation (HFPV) is a non-conventional ventilatory modality which has proven highly effective in patients with severe gas exchange impairment. However, at the present time, HFPV ventilator provides only airway pressure measurement. The airway pressure measurements and gas exchange analysis are currently the only parameters that guide the physician during the HFPV ventilator setup and treatment monitoring. The evaluation of respiratory system resistance and compliance parameters in patients undergoing mechanical ventilation is used for lung dysfunctions detection, ventilation setup and treatment effect evaluation. Furthermore, the pressure measured by ventilator represents the sum of the endotracheal tube pressure drop and the tracheal pressure. From the clinical point of view, it is very important to take into account the real amount of pressure dissipated by endotracheal tube to avoid lung injury. HFPV is pressure controlled logic ventilation, thus hypoventilation and hyperventilation cases are possible because of tidal volume variations in function of pulmonary and endotracheal tube impedance. This thesis offers a new approach for HFPV ventilator setup in accordance with protective ventilatory strategy and optimization of alveolar recruitment using estimation of the respiratory mechanics parameters and endotracheal pressure drop. Respiratory system resistance and compliance parameters were estimated, firstly in vitro and successively in patients undergoing HFPV, applying least squares regression on Dorkin high frequency model starting from measured respiratory signals. The Blasius model was identified as the most adequate to estimate pressure drop across the endotracheal tube during HFPV. Beside measurement device was developed in order to measure respiratory parameters in patients undergoing HFPV. The possibility to tailor HFPV ventilator setup, using respiratory signals measurement and estimation of respiratory system resistance, compliance and endotracheal tube pressure drop, provided by this thesis, opens a new prospective to this particular ventilatory strategy, improving its beneficial effects and minimizing ventilator-induced lung damage.
XXVII Ciclo
1981
Park, Seonyeong. "Respiratory Prediction and Image Quality Improvement of 4D Cone Beam CT and MRI for Lung Tumor Treatments." VCU Scholars Compass, 2017. http://scholarscompass.vcu.edu/etd/5046.
Повний текст джерелаHult, Peter. "Bioacoustic principles used in monitoring and diagnostic applications /." Linköping : Univ, 2002. http://www.bibl.liu.se/liupubl/disp/disp2002/tek778s.pdf.
Повний текст джерелаLucangelo, Umberto. "Titration of High Frequency Percussive Ventilation by means of real-time monitoring of the viscoelastic respiratory system properties and endotracheal tubes pressure drop." Doctoral thesis, Università degli studi di Trieste, 2014. http://hdl.handle.net/10077/9992.
Повний текст джерелаThe use of High Frequency Percussive Ventilation (HFPV) is still debated although this type of non-conventional ventilation has proven effective and safe in patients with acute respiratory failure. In the clinical practice, HFPV is not an intuitive ventilatory modality and the absence of real-time delivered volume monitoring produces disaffection among the physicians. Avoiding the "volutrauma" is the cornerstone of the "protective ventilation strategy", which assumes a constant monitoring of inspiratory volume delivered to the patient. Currently the system capable of delivering HFPV is the VDR-4® (Volumetric Diffusive Respirator), which provides only analog airway pressure waveform and digital output of peak and the mean airway pressure. The latter is involved in the determination of oxygenation and hemodynamics, irrespective of the mode of ventilation. At the present time, the mean airway pressure, together with gas exchange analysis, are the only parameters that indirectly guide the physician in assessing the clinical effectiveness of HFPV. Till now, flow, volume and pressure curves generated by HFPV have never been studied in relation to the specific patients respiratory mechanics. The real-time examination of these parameters could allow the physicians to analyze and understand elements of respiratory system mechanics as compliance (Crs), resistance (Rrs), inertance (Irs) and of patient-ventilator interaction. The mechanical effects are complex and result from interactions between ventilator settings and patient’s respiratory system impedance. The aim of this doctoral thesis was to acquire and study volume and respiratory parameters during HFPV in order to explain this complex patients-machine interaction and transfer the results in clinical practice.
XXVI Ciclo
1959
Breuilly, Marine. "Imagerie TEMP 4D du petit animal : estimation du mouvement respiratoire et de la biodistribution de l'iode." Phd thesis, Université Nice Sophia Antipolis, 2013. http://tel.archives-ouvertes.fr/tel-00908962.
Повний текст джерелаLi, Yelei. "Heartbeat detection, classification and coupling analysis using Electrocardiography data." Case Western Reserve University School of Graduate Studies / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=case1405084050.
Повний текст джерелаLuguern, Duncan. "Nouvelle approche pour l'estimation du rythme respiratoire basée sur la photopléthysmographie sans contact." Thesis, Bourgogne Franche-Comté, 2021. http://www.theses.fr/2021UBFCK005.
Повний текст джерелаRespiratory rhythm is important information in medical context.Its assessment allows to predict some medical complications that could lead to death.However, it is often neglected by the medical staff due to a bad comprehension of its importance, or a lack of time.Automated measurement methods allow to improve this by continuously giving respiratory rate.Most of these methods needs a contact with the patient to efficiently measure the breathing rate.Unfortunately it leads to some issues which could forbid measurement or make it unconfortable for continuous monitoring.The continuous, every-day monitoring especially needs to be as discrete as possible to be forgotten by the patient.To deal with these drawbacks, several non contact respiratory rate assessment methods are currently developped.In these methods, the remote photoplethysmography uses the color variation of the skin due to blood volume in capillaries to obtain a cardiac and respiratory correlated signal.In this thesis, we focused on improving the respiratory rate measurement using remote photoplethysmography.To do this, we developped some methods whose goals are to efficiently combine color signals that were extracted from the video to obtain a single signal that maximizes the breathing information.In a second part, we developped a processing pipeline to assess the breathing rate from all informations that could be extracted from remote photoplethysmography signals.The processing pipeline was tested with state of the art combination methods and the methods that were developped during the thesis
Wallach, Daphné. "Compensation du mouvement respiratoire en TEP/TDM à l'aide de la super-résolution." Phd thesis, Université de Bretagne occidentale - Brest, 2011. http://tel.archives-ouvertes.fr/tel-00714263.
Повний текст джерелаCosta, Taisa Daiana da. "Sistema para sincronização automática de estimulação elétrica no tratamento de insuficiência respiratória em pessoas com lesão medular." Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1271.
Повний текст джерелаA insuficiência respiratória gerada pela lesão medular, em pessoas com tetraplegia e paraplegia torácica alta, tem sido uma das principais causas de morte desses indivíduos. A paralisação, total ou parcial, dos músculos abdominais e do diafragma dificulta a produção de tosse e diminui o volume corrente da ventilação. Este problema pode ser amenizado por meio do tratamento com estimulação elétrica funcional transcutânea (EEFT), na musculatura diafragmática e abdominal, sincronizada com a respiração espontânea. Poucos estudos têm sido direcionados a esta área e foi constatado que é de grande interesse científico que seja desenvolvido um sistema capaz de automaticamente sincronizar a estimulação elétrica com os eventos de inspiração (estimulação diafragmática) e expiração (estimulação abdominal). Por isso, nesta dissertação, desenvolveu-se um sistema de aquisição de sinal respiratório e detecção dos eventos de inspiração e expiração para sincronismo da EEFT durante a respiração tranquila. O sistema emprega uma cinta elástica acoplada a uma célula de carga baseada em strain gauges para a aquisição do sinal respiratório. Um algoritmo, baseado em análise estatística do sinal, foi desenvolvido para a detecção das fases de inspiração e expiração.Testes foram realizados em oito voluntários hígidos. A cinta foi posicionada na região da última costela, e sinais foram adquiridos com o auxílio de um osciloscópio digital. Um fisioterapeuta ajudou na análise dos sinais. Foi realizada a contagem de inspirações e expirações detectadas corretamente. O resultado dos testes alcançou a taxa de 82% de acerto na detecção dos eventos inspiratórios, e 96% para os eventos expiratórios. Os resultados indicam que o sistema desenvolvido é eficiente para a aquisição de sinais respiratórios e o algoritmo criado pode propiciar a sincronização da EEFT, com o paciente tratado em posição quase estática.
The respiratory failure, caused by spinal cord injury in people with high thoracic paraplegia and tetraplegia, has been the major cause of death for those individuals. The total or partial paralysis of the abdominal muscles and the diaphragm hinders the production of cough and decreases tidal volume. This problem can be alleviated by treatment with transcutaneous functional electrical stimulation (TFES), on diaphragm and abdominal muscles synchronized with the spontaneous respiration. Few studies have been conducted on this matter, and it was found that is of great scientific interest the development of a system capable of automatically triggering the electrical stimulation with inspiration (diaphragmatic stimulation) and expiration events (abdominal stimulation). Therefore, in this work, a respiratory signal acquisition system was developed for the detection of inspiration and expiration events for triggering the electrical stimulation during quiet breathing. The system employs an elastic belt attached to a load cell based on strain gauges for acquiring the respiratory signal. An algorithm based on signal statistical analysis was developed for the detection of inspiration and expiration events. Tests were carried out in eight healthy volunteers. The belt was positioned at the last rib region, and signals were obtained with the aid of a digital oscilloscope. A physical therapist helped in the analysis of the signals by counting the inspiratory and expiratory events. The results reached the accuracy of 82% in the detection of inspiratory events, and 96% for expiratory events. The results indicate that the developed system is effective for the acquisition of respiratory signals and the created algorithm can provide synchronization of TFES with the patient in quasi-static situation during treatment.
Porras, Desiderio Cano. "Comparação da assincronia toracoabdominal ao repouso e ao exercício em pacientes com doença pulmonar obstrutiva crônica utilizando diferentes metodologias." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/5/5170/tde-27082014-091225/.
Повний текст джерелаChronic obstructive pulmonary disease (COPD) patients can present thoracoabdominal asynchrony (TAA). There are several TAA estimation techniques, however, there is no consensus about which is the most appropriate. The aim of this study was to compare two thoracoabdominal asynchrony quantification techniques and to assess chest wall ventilatory inefficiency in COPD patients at rest and during exercise. We evaluated 22 COPD patients (FEV1 40,2±10,5% predicted) and 13 healthy controls (CG) matched by age, gender and body mass index. Thoracoabdominal kinematics was assessed via optoelectronic plethysmography at rest and during mild and moderate exercise (70 % maximum workload) in a cycle ergometer. TAA was calculated among upper (URC) and lower ribcage (LRC) and abdomen (ABD) by using the phase angle (PA) and phase relation (PR) approaches. Ventilatory Inefficiency was estimated in each compartment as the difference between the maximal volume (VM) and the volume (VC) calculated according to respiratory timing (sum of volume in the 3 compartments) divided by the maximal volume (VM-VC)/VM. COPD patients were classified as asynchronous (AT group) or not (NA group) by using as reference the values on the controls. Chi-square or Fisher\'s exact test was used for assessing the patients differentiation between the two TAA quantification approaches and two-way ANOVA was used to compare respiratory parameters among groups (CG, AT and NA). Statistical significance was set at 5% level. PA approach determined more patients as asynchronous when compared to RF at rest (respectively, 15 vs. 7) and during mild (11 vs. 3) and moderate (14 vs. 8) exercise. Asynchrony values in AT group among URC-LRC and LRC-ABD were greater at rest (respectively, 35.7±45.4° and -42.2±42.5° with PA and 61.8±29.1° and -66.9±27.4° with PR) and during mild (PA: 53.3±35.6° and -55.8±40.4°; PR: 106.1±40.3° and -124.8±17.2°) and moderate exercise (PA: 61.6±55.1° and - 75.9±44.8°; PR: 85.9±23.6° and -81.8±42.2°) when compared to NA (p < 0.05) and CG (p < 0.05). Analysis among URC-ABD presented no difference between groups. It was observed that AT group presented a smaller LRC contribution and greater ventilatory inefficiency during all assessing moments and, during moderate exercise, had a lower tidal volume when compared to NA and CG. Our results suggest that phase angle approach presents larger TAA detection in COPD patients. This asynchrony seems to occur mainly in the lower ribcage and be associated with decreased contribution and increased ventilatory inefficiency of this compartment
Pérez, Trenard Diego Oswaldo. "Optimal control of non-invasive neuromodulation for the treatment of sleep apnea syndromes." Thesis, Rennes 1, 2018. http://www.theses.fr/2018REN1S014/document.
Повний текст джерелаSleep apnea syndrome (SAS) is a multifactorial disease characterized by recurrent episodes of breathing pauses or significant reductions in respiratory amplitude during sleep. These episodes may provoke acute cardiorespiratory responses along with alterations of the sleep structure, which may be deleterious in the long term. Several therapies have been proposed for the treatment of SAS, being continuous positive airway pressure the gold standard treatment. Despite its excellent results in symptomatic patients, there is a 15% initial refusal rate and long term adherence is difficult to achieve in minimally symptomatic patients. Therefore, the development of non-invasive SAS treatment methods, with improved acceptability, is of major importance. The objective of this PhD thesis is to propose new signal processing and control methods of non-invasive neuromodulation for the treatment of SAS. The hypothesis underlying this work is that bursts of kinesthetic stimulation delivered during the early phase of apneas or hypopneas may elicit a controlled startle response that can activate sub-cortical centers controlling upper airways muscles and the autonomic nervous system, stopping respiratory events without generating a cortical arousal. In this context, the first part of this manuscript is dedicated to the description of a novel real-time monitoring and therapeutic neuromodulation system, which functions as a multi-purpose device for SAS diagnosis and treatment through kinesthetic stimulation. This system has been developed in the framework of an ANR TecSan project led by our laboratory, with the participation of Sorin CRM SAS. The main contributions in this thesis are focused on the signal processing and control aspects of this system, as well as the electronics associated. Another contribution is related to the evaluation of these methods and devices through specific clinical protocols. In a second part, we propose a first optimal On/Off control method for delivering kinesthetic stimulation, using as control variable the output of a real-time respiratory event detector. A unique stimulation strategy where a constant stimulation amplitude is applied upon event detention was implemented in a first clinical protocol, dedicated to assessing the patient response to therapy. Results showed that 75% of the patients responded correctly to therapy, showing statistically significant reductions in respiratory event durations. Also, significant decreases in the SaO2 variability were also found when implementing a novel acute analysis method. Since we hypothesized that inappropriate patient selection could explain the observed lack of response in 25% of patients, we proposed a method to differentiate patients who could benefit from this therapy based on the estimation of complexity-based indexes of heart rate variability. Results of these analyses showed that the effectiveness of this therapy seems correlated to a functional autonomic nervous system. Finally, an improved closed-loop control method integrating concurrent, coupled proportional-derivative (PD) controllers in order to adaptively change the kinesthetic stimulation was proposed. It uses as control variables three physiological signals recorded in real-time: Nasal pressure, oxygen saturation and the electrocardiogram signal. A second clinical protocol with the main objective of validating the control algorithm for patient-specific adaptive kinesthetic stimulation was launched. Several improvements to the first version of the system were developed to allow the integration of the proposed controller. Preliminary results from the first phase of this study validated the proposed controller operation and showed that the controller was able to provide adaptive kinesthetic stimulation in function of the patient-specific responses. A second phase of this study implementing the proposed controller and the set of the selected control parameters from the first phase is currently ongoing
Шатровська, Марія Степанівна, та Mariia Shatrovska. "Комп'ютерний засіб тестування методів обробки сигналів дихання людини". Master's thesis, Тернопільський національний технічний університет імені Івана Пулюя, 2021. http://elartu.tntu.edu.ua/handle/lib/36237.
Повний текст джерелаНаведено результати розробки комп'ютерного засобу тестування методів обробки сигналів дихання як шуму повторного та амплітудо-модульованого методами імітаційного моделювання та програмного засобу Matlab. Імітаційна модель сигналу дихання забезпечує за даними медичних показників (морфопараметрів) імітувати сигнали різних станів органів дихання, що є важливим при тестуванні методів та розроблених їх підґрунті програмних засобів обробки сигналів у комп’ютерних аускультаційних системах. Імітаційна модель сигналу дихання реалізована через відповідне програмне забезпечення (комп’ютерний засіб) в Matlab та є адекватним засобом імітації сигналів дихання різни станів з мінімальними відхиленнями від емпіричних сигналів.
The results of development of a computer tool for testing methods of processing respiratory signals as repeated and amplitude-modulated noise by simulation methods and Matlab software are presented. The simulation model of the respiratory signal provides, according to medical indicators (morphoparameters), to simulate the signals of different respiratory conditions, which is important when testing methods and software based on signal processing in computer auscultation systems. The simulation model of the respiratory signal is implemented through the appropriate software (computer tool) in Matlab and is an adequate means of simulating respiratory signals of different states with minimal deviations from the empirical signals.
ВСТУП 8 РОЗДІЛ 1. АНАЛІТИЧНА ЧАСТИНА 10 1.1. Процес утворення сигналів дихання 10 1.2. Сигнал дихання та його показники 12 1.3. Відомі матмоделі сигналів дихання 17 1.3.1. Стаціонарний випадковий процес 17 1.3.2. Стаціонарна випадкова центрована функція та періодична функція 18 1.3.3. Адитивна суміш шумової та періодичної компонент 19 1.3.4. ПКВП 22 1.4. Висновки до розділу 1 23 РОЗДІЛ 2. ОСНОВНА ЧАСТИНА 24 2.1. Реєстрація сигналів дихання 24 2.2. Оцінювання показників сигналу дихання 26 2.3. Матмодель сигналів дихання 31 2.4. Суть тестування методів обробки сигналів дихання 34 2.5. Імітаційна модель сигналів дихання 36 2.6. Узагальнене подання алгоритму імітування сигналів дихання 45 2.7. Блок-схема імітаційного моделювання дихального шуму 46 2.8. Висновки до розділу 2 48 РОЗДІЛ 3. НАУКОВО-ДОСЛІДНА ЧАСТИНА 49 3.1. Блок-схема комп’ютерного засобу тестування методів обробки сигналів дихання 49 3.2. Блок-схема комп’ютерного засобу тестування 50 3.3. Реалізація комп’ютерного засобу тестування 51 3.4. Результати роботи комп’ютерного засобу тестування 55 3.5. Висновки до розділу 3 57 7 РОЗДІЛ 4. ОХОРОНА ПРАЦІ ТА БЕЗПЕКА В НАДЗВИЧАЙНИХ СИТУАЦІЯХ 58 4.1 Охорона праці 58 4.2 Безпека в надзвичайних ситуаціях 61 4.3 Висновки до розділу 4 65 ЗАГАЛЬНІ ВИСНОВКИ 66 ПЕРЕЛІК ПОСИЛАНЬ 67 ДОДАТКИ 78 ДОДАТОК А. Програмне забезпечення комп’ютерного засобу тестування методів обробки сигналів дихання 79 ДОДАТОК Б. Копія тези 81 ДОДАТОК В. Копія тези 83
Shen, Yi-Hsiang, and 沈義翔. "Human Respiratory Feature Extraction on A UWB Radar Signal Processing Platform." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/93269462631188359405.
Повний текст джерела國立清華大學
通訊工程研究所
101
This paper presents a ultra-wideband (UWB) impulse-radio radar signal processing platform. This platform is integrated with a front-end radar chip for human respiratory feature extraction and signal compression. The conventional radar detection algorithms only extract the respiration rate for medical diagnosis. However, there is more information in the radar-detected respiratory signals which can be useful for medical diagnosis. Thus, this study proposed a modified raised cosine model and an iterative correlation algorithm to extract more respiratory features, such as inspiration and expiration speed, respiration intensity, and respiration holding ratio. Moreover, the extracted features are useful in remote medical monitoring system since they can be seen as compressed respiratory signals. Transmission bandwidth can be saved by transmitting the extracted features instead of lots of sampled data. The proposed algorithm and architecture is designed and implemented on a radar signal processing platform with the ARM processor and FPGA logic array. Human respiratory signals of 0.1 to 1 Hz rate are detected and analyzed along with other information at each period.
Hong, Guo-Feng, and 洪國峰. "An Integrated UWB Radar Signal Processing System for Real-Time Human Respiratory Feature Extraction." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/37452850499163195906.
Повний текст джерелаChiu, Yu-Fang, and 邱于芳. "A Low-Complexity UWB-Radar Signal Processing System for Real-Time Human Respiratory Feature Extraction." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/22482580742784822841.
Повний текст джерела國立清華大學
電機工程學系
102
This paper presents a real time ultra-wideband (UWB) impulse-radio radar signal processing platform with reduced complexity. This platform is integrated with a radar front-end chip for human respiratory feature extraction and signal compression. Conventional radar detection algorithms only extract respiration rate for medical diagnosis. However, there is more useful information in the radar-detected respiratory signals for medical diagnosis. Thus, this study proposed a four segment linear wave model and an iterative correlation search algorithm to extract more respiratory features, such as inspiration and expiration speed, respiration intensity, and respiration holding ratio between inspiration and expiration. Moreover, since the iterative correlation search algorithms involves high computation cost, this study applies an early termination scheme and down sampling to reduce the complexity with negligible performance degradation. The extracted features are also useful in a remote medical monitoring system because they can be regarded as compressed respiratory signals. One-period human respiratory cycle can be expressed by extracted features instead of lots of samples. Transmission bandwidth or storage capacity can be greatly saved by transmitting or storing the extracted features. The proposed algorithm and architecture was designed and implemented on a real time radar signal processing platform with a FPGA chip. Human respiratory signals from 0.1 to 1 Hz rate are detected and analyzed along with other information in each period.
Yadollahi, Azadeh. "Respiratory sound analysis for flow estimation during wakefulness and sleep, and its applications for sleep apnea detection and monitoring." 2011. http://hdl.handle.net/1993/4590.
Повний текст джерелаLi, Pin. "Effects of carbon nanotubes on airway epithelial cells and model lipid bilayers : proteomic and biophysical studies." Thesis, 2014. http://hdl.handle.net/1805/5968.
Повний текст джерелаCarbon nanomaterials are widely produced and used in industry, medicine and scientific research. To examine the impact of exposure to nanoparticles on human health, the human airway epithelial cell line, Calu-3, was used to evaluate changes in the cellular proteome that could account for alterations in cellular function of airway epithelia after 24 h exposure to 10 μg/mL and 100 ng/mL of two common carbon nanoparticles, singleand multi-wall carbon nanotubes (SWCNT, MWCNT). After exposure to the nanoparticles, label-free quantitative mass spectrometry (LFQMS) was used to study differential protein expression. Ingenuity Pathway Analysis (IPA) was used to conduct a bioinformatics analysis of proteins identified by LFQMS. Interestingly, after exposure to a high concentration (10 μg/mL; 0.4 μg/cm2) of MWCNT or SWCNT, only 8 and 13 proteins, respectively, exhibited changes in abundance. In contrast, the abundance of hundreds of proteins was altered in response to a low concentration (100 ng/mL; 4 ng/cm2) of either CNT. Of the 281 and 282 proteins that were significantly altered in response to MWCNT or SWCNT, respectively, 231 proteins were the same. Bioinformatic analyses found that the proteins common to both kinds of nanotubes are associated with the cellular functions of cell death and survival, cell-to-cell signaling and interaction, cellular assembly and organization, cellular growth and proliferation, infectious disease, molecular transport and protein synthesis. The decrease in expression of the majority proteins suggests a general stress response to protect cells. The STRING database was used to analyze the various functional protein networks. Interestingly, some proteins like cadherin 1 (CDH1), signal transducer and activator of transcription 1 (STAT1), junction plakoglobin (JUP), and apoptosis-associated speck-like protein containing a CARD (PYCARD), appear in several functional categories and tend to be in the center of the networks. This central positioning suggests they may play important roles in multiple cellular functions and activities that are altered in response to carbon nanotube exposure. To examine the effect of nanotubes on the plasma membrane, we investigated the interaction of short purified MWCNT with model lipid membranes using a planar bilayer workstation. Bilayer lipid membranes were synthesized using neutral 1, 2-diphytanoylsn-glycero-3-phosphocholine (DPhPC) in 1 M KCl. The ion channel model protein, Gramicidin A (gA), was incorporated into the bilayers and used to measure the effect of MWCNT on ion transport. The opening and closing of ion channels, amplitude of current, and open probability and lifetime of ion channels were measured and analyzed by Clampfit. The presence of an intermediate concentration of MWCNT (2 μg/ml) could be related to a statistically significant decrease of the open probability and lifetime of gA channels. The proteomic studies revealed changes in response to CNT exposure. An analysis of the changes using multiple databases revealed alterations in pathways, which were consistent with the physiological changes that were observed in cultured cells exposed to very low concentrations of CNT. The physiological changes included the break down of the barrier function and the inhibition of the mucocillary clearance, both of which could increase the risk of CNT’s toxicity to human health. The biophysical studies indicate MWCNTs have an effect on single channel kinetics of Gramicidin A model cation channel. These changes are consistent with the inhibitory effect of nanoparticles on hormone stimulated transepithelial ion flux, but additional experiments will be necessary to substantiate this correlation.