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Defense Science Research Conference and Expo (DSR), 2011

Date 3-5 Aug. 2011

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Displaying Results 1 - 25 of 88
  • Modeling of spinal cord and investigation of the injury mechanism during compression

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (470 KB) |  | HTML iconHTML  

    To establish a Finite element model of thoracolumbar spinal cord and investigate the injury mechanism caused by burst fracture using finite element simulation. A three-dimensional finite element model of human spinal cord at T-12 and L-l level was developed. The model was validated with previous published literatures in terms of uniaxial tension, compression. Then, a burst fracture compressive simulation was performed to study the spinal cord injury mechanism. The strain distribution in the eight function regions of white and grey matter in transverse section was quantitatively documented with the bony fragments' enroachment. When the encroachment increased to 2.7 mm, the strain in ventral cord tissue (AHMN (DM): 0.18, AHMN (PM): 0.26, VTF: 0.29 , ASCT: 0.04) is higher than dorsal (SG: 0.02, CN: 0.05, PSCT: 0.01, FG: 0.02). As the encroachement increased to maximum value (5.4 mm), the strains had no difference between ventral and dorsal spinal cord tissue. View full abstract»

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  • Strategies for pathway-based analysis of genome-wide SNP data

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (195 KB) |  | HTML iconHTML  

    Numerous genome-wide association studies (GWAS) have been performed in order to determine the susceptible loci of diseases. However, most diseases still cannot be explained by a single locus. Pathway-based methods address this problem by combining those small effects into groups of related genes or pathways. However, because pathway-based approaches consist of multiple steps, there is much room for improvement. This paper presents an improved method for translating list of SNPs from GWAS into list of genes. We incrementally adjusted and compared different modifications applied to Parkinson's disease (PD) genome-wide SNP data and then used GSEA-P to analyze the resulting list of genes. After careful adjustments, we are able to identify more relevant pathways that were not found previously. View full abstract»

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  • A study on sleep EEG Using sample entropy and power spectrum analysis

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (247 KB) |  | HTML iconHTML  

    Research on the automation of sleep stage classification, particularly single channel EEG, has been a challenge for many years. The research aims to look into the analysis and evaluation of feature extraction techniques and classification methods that are important to properly classify sleep stages with limited channels. Sample entropy, and the power spectrum of the harmonic parameters using infinite impulse response filters and wavelet transform were used to extract features from the data taken from Physionet database. A total of 13 features were initially extracted and used for the training and testing of the sleep stage classification system. Analysis of the training data showed a distinct combination patterns between the sample entropy and harmonic parameters with a change in the sleep stage. In addition, a prototype for the sleep stage classification system was implemented. Support Vector Machine (SVM) was utilized for the classification system. While the training data were extracted from several database. Further refinement of the data and the program could be useful for a test the sleep stage classification on other database or data. View full abstract»

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  • A novel method to extract ECG morphology from scanned ECG records

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (244 KB) |  | HTML iconHTML  

    ECG is a valuable source of information regarding the patient's clinical data repository. Archiving the paper Electrocardiogram (ECG) trace as an image requires immense storage space and manpower for storage and retrieval of the patient records. Objective of this paper is to extract the ECG Morphological features from the paper ECG. In this paper, we have proposed a novel technique to extract the ECG Morphological features. The proposed algorithm has been evaluated with 25 patient's ECG sheets printed from 12-lead ECG equipments. Further, the proposed technique enhances the accuracy of heart rate and morphological feature extraction from the obtained time series signal. The evaluation of the digital time series data conversion algorithm has been performed by comparing obtained heart rate with value printed on the paper. The accuracy of the heart rate was found to be 99.12%. Evaluation of the proposed slope method for ECG morphological feature extraction was done by comparing the obtained values with manual data and this method offered an accuracy of 97.09%. View full abstract»

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  • Clinical applications of diffuse reflectance spectroscopy in normal and prediabetic subjects-A pilot study

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (189 KB) |  | HTML iconHTML  

    A pilot study was conducted in 4 different regions on the foot sole of normal and prediabetic subjects to determine the ratios of oxy and deoxy hemoglobin bands using diffuse reflectance spectroscopy in visible range. The reflectance spectra of normal subjects showed a greater absorption dips at 542 nm. In conclusion the ratio of R542/R555, ratio of oxy and deoxy hemoglobin bands would be helpful in characterizing tissue oxygenation levels in normal and prediabetic subjects. View full abstract»

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  • Relationship between shoe heel shape and foot pressure while walking

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (356 KB) |  | HTML iconHTML  

    Women have a lot of chances to wear high-heeled shoes for work on business occasions and for fashion. Even though several reports have demonstrated the physical risk, women continue to wear high-heeled shoes. The wedge sole is popular for some women as it is fashionable and allows the body weight to distributed over the entire bottom of the shoe, and the load on the foot is relatively small compared to the pin heel. However, its risks are not insignificant, and the possibility of falling must be considered. This paper clarifies the characteristics of shoe heel shape by recording foot pressure while walks. It describes a comparison of foot pressure in 7 foot regions for four different shoes (3 high-heeled with the same height and one low heeled). The pressure was captured by an insole type foot pressure sensor. The results of several experiments verify that the wedge sole with a strap gives stable walking even though the heel is high enough for fashion. View full abstract»

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  • Fingerprint verification: A comparison of three approaches

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (303 KB) |  | HTML iconHTML  

    Fingerprint verification is used for person authentication. This has wide application from low risk to safety critical authentication systems. Research in this field has a long history. A number of approaches have been implemented for effective and efficient fingerprint verification. This article reports the results of quantitative comparison of different fingerprint verification approaches. We conducted an experiment of fingerprint verification using three approaches- biometric technique, Genetic algorithm and Back propagation neural network. The performance of the three approaches was assessed in terms of False Acceptance Rate (FAR), False Rejection Rate (FRR) and execution time. Our comparative analysis reveals that for small number of images there is no significant difference in performance among the chosen approaches. View full abstract»

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  • Gait Authentication using a wearable sensor

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1931 KB) |  | HTML iconHTML  

    ICT and MEMS technology are becoming pervasive. Therefore, wearable sensors are receiving a lot of attention. This raises the feasibility of various sensor-based services. This paper introduces a gait authentication method based on wearable sensors. We capture gait data from a wearable sensor and analyze personal gait characteristics on the basis of the data obtained. We propose and evaluate an authentication algorithm. Results confirm that when the threshold value was 18.4, EER was 23.1%. View full abstract»

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  • Feasibility of assessing rehabilitation status by using foot pressure sensor while walking

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (262 KB) |  | HTML iconHTML  

    The world is facing the problem of rapid aging. ICT (Information and Communication Technology) is capable of alleviating this problem. Among the technologies available, simple physical sensors will be the key to capturing a variety of information including human vital information even in the home. This will result in creating a new infrastructure or service of Distributed Diagnosis and Home Healthcare. In order to clarify how sensors-based systems can assess the rehabilitation status of people with leg injuries, this paper describes the results of on-going experiments in which a wearable foot pressure sensor is used to capture foot pressure while walking. The results show that rehabilitation progress can be verified by the system and help motivate the subject to continue with rehabilitation. View full abstract»

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  • Comparing mathematical models of cell adhesion in tumors

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (400 KB) |  | HTML iconHTML  

    Cancer progression accompanies changes in cell adhesion characteristics, which is crucial for cancer cell invasion and metastasis. Drugs altering cell adhesion have been suggested as a possible therapeutic treatment for cancer. Tumor cell adhesion is thus an important topic of current investigation. Recently individual cell (agent)-based in silico tumor models have incorporated mathematical models of cell adhesion. However, cell adhesion has been modeled in various ways in different studies. The first, Lennard-Jones potential model, is extrapolated from attractive/repulsive interactions between inert molecules. The second, JKR model, is derived from van-der Waals contact forces between non-spontaneously adhering solid elastic bodies. The third, cellular Potts model, is an adaptation of the Ising model of ferromagnetism to a spontaneously adhering population of cells. We compare these three mathematical models of cell adhesion and show how they give different perspectives to tumor growth, morphology and effectiveness of therapy. We also discuss how these models predict multi-nodular tumor morphology which is hitherto unaddressed in the literature. View full abstract»

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  • Finite element analysis of stress on the cells injected into the patient's intervertebralDisc

    Page(s): 1 - 4
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (232 KB)  

    Tissue diseases impact on human life, This review can be appropriate for physicians to thus recognize the best injection site. New science of tissue engineering is the use of modeling community could do to help humanity, this paper, 1/4 of IVD is modeled as ax symmetric where the living cells are assumed to be soft with isotropic, elastic properties and IVD are assumed to be viscoelastic parameters, Two places to inject the cells are considered and are compared, 1) top of the nucleus, 2) middle of the nucleus. By comparing these two cases can be diagnosed the best place to inject cells in the IVD is in the middle. View full abstract»

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  • Effect of plasma viscosity on blood flow behaviors in microvessels

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (404 KB) |  | HTML iconHTML  

    To pursue a better understanding of the counter intuitive observations of plasma viscosity effects on microscopic blood flows, we have numerically simulated the red blood cell dynamics in shear and channel flows and multiple cell flow behaviors in straight microvessels. Our simulations indicate that, in a high-viscosity suspending medium, red blood cells appear more deformable, and this enhances the cell migration in straight microvessels. Also the cell free layer change with plasma viscosity might be helpful to interpret the increase in functional capillary density observed in hemodilution experiments with high-viscosity plasma expanders. Such information could be important to relevant biomedical applications. View full abstract»

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  • Effect of diffraction wave at the reflector aperture on shock wave lithotripsy

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (279 KB) |  | HTML iconHTML  

    To study the effect of diffraction wave evolved in the shock wave (SW) propagation on the performance of extracorporeal lithotripter, an edge blocker was designed to fit at the outside surface of the ellipsoidal reflector of a Dornier HM-3 lithotripter. With this modification, the contribution of the diffraction wave to the tensile component of SW at the focal region could be reduced significantly (3.2±0.54 μs vs. 5.83±0.56 μs). However, the amplitude and duration of the compressive wave as well as the -6 dB beam width and the amplitude of the tensile wave were almost unchanged. The suppression on bubble cavitation was confirmed using the passive cavitation detection technique. At the lithotripter focus, while 30 SWs can cause rupture of a blood vessel phantom using the HM-3 lithotripter at 20 kV; no rupture could be found after 300 SWs with the edge blocker. On the other hand, after 200 SWs the HM-3 lithotripter at 20 kV can achieve a stone fragmentation of 50.4±2.0% on plaster-of-Paris stone phantom, which is comparable to that of using the edge blocker (46.8±4.1%, p=0.005). Altogether, the diffraction wave is a major reason for the bubble expansion at the lithotripter focus and the modification on it at the lithotripter aperture can produce satisfactory stone comminution while significantly reducing the potential for vessel rupture in shock wave lithotripsy. View full abstract»

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  • Biomechanical effect of footwear intervene of forefoot loading during landing movement

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (181 KB) |  | HTML iconHTML  

    This study investigated the forefoot loading character under flexible sole condition while performing landing maneuver. Twenty healthy male volunteers have participated in the test. The insole and outsole loading were measured at the same time. Both peak pressure and force-time integral of plantar surface was largely reduced in the medial metatarsals area. The results of this study shown that the forefoot impact loading could be effectively relieved through the footwear during landing movement. Also, the kinematic data of forefoot in footwear condition need further studied. View full abstract»

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  • Scale-space analysis of event-related fMRI data using higher harmonics

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (331 KB) |  | HTML iconHTML  

    Scale-space analysis is able to detect activation at various scales from a functional MR brain slice. Though scale space analysis has been used in functional MRI, its use has been limited to periodic block-based experiments. This paper extends scale space analysis to event-related experiments. Furthermore, the method uses higher harmonics of stimulus frequency, which contain considerable energy especially in periodic event-related data. The use of these harmonics results in a chi-square random field of higher degree and improves accuracy in activation detection. View full abstract»

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  • A ranking-based method to predict protein function in terms of gene ontology

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (331 KB) |  | HTML iconHTML  

    In the post genomic era, protein function prediction has become the focus of many researches. Methods that predict function from the high-throughput experimental screening have gained popularity due to the reduced cost of conducting genome wide functional screening. In this work we predict the function of uncharacterized proteins by ranking the functions based on the protein interaction data with the help of gene ontology terms. We used Neighbor counting, Chi-square, S-weight, and FS-weight methods to predict the functions of a set of 100 un-annotated proteins. Among them, the ZNF24 and VDP proteins, which were predicted to be involved in transcription regulation and vesicle mediated transport, respectively, obtained the best results. In confirmation, our results were mostly confirmed by Pfam and WoLF Psort shows possible reliability of our method, and it therefore can be applied in protein function prediction when the prior knowledge such as sequences or structures is still not available. View full abstract»

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  • Aromatic chemicals production using phenylalnine ammonia lyase expressing Streptomyces lividans

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (474 KB) |  | HTML iconHTML  

    Cinnamic acid production was demonstrated using Streptomyces as a host. A gene encoding phenylalanine ammonia lyase (PAL) from Streptomyces maritimus was introduced into Streptomyces lividans and its expression was confirmed by western blot analysis. After 4 days cultivation using glucose as a carbon source, the maximal level of cinnamic acid reached 210 mg/L. When glycerol (30 g/L) was used as the carbon source, the maximal level of produced cinnamic acid reached 450 mg/L. In addition, using raw starch, xylose and xylan as the carbon source, the maximal level of cinnamic acid reached 460, 300, 130 mg/L, respectively. We demonstrated that S. lividans has great potential to produce cinnamic acid as well as other aromatic compounds. View full abstract»

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  • From system-centric to data-centric logging - Accountability, trust & security in cloud computing

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (177 KB) |  | HTML iconHTML  

    Cloud computing signifies a paradigm shift from owning computing systems to buying computing services. As a result of this paradigm shift, many key concerns such as the transparency of data transfer and access within the cloud, and the lack of clarity in data ownership were surfaced. To address these concerns, we propose a new way of approaching traditional security and trust problems: To adopt a detective, data-centric thinking instead of the classical preventive, system-centric thinking. While classical preventive approaches are useful, they play a catch-up game; often do not address the problems (i.e. data accountability, data retention, etc) directly. In this paper, we propose a data-centric, detective approach to increase trust and security of data in the cloud. Our framework, known as TrustCloud, contains a suite of techniques that address cloud security, trust and accountability from a detective approach at all levels of granularity. TrustCloud also extends detective techniques to policies and regulations governing IT systems. View full abstract»

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  • Robot-assisted gait rehabilitation: From exoskeletons to gait systems

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1214 KB) |  | HTML iconHTML  

    In recent years, robotic technologies have been applied to build assistive robots, such as robotic exoskeletons and rehabilitation robots. Based on the clinical considerations, new trends of rehabilitation, like over-ground rehabilitation robots and home-based mobile rehabilitation robots, have emerged by combining both the knowledge from the exoskeleton and the rehabilitation robots. In this article, we review some of the important assistive and rehabilitation robots, in terms of their hardware, actuation, sensory and controls systems. The paper ends with a discussion on the future trends of the rehabilitation robots, especially on clinical-based considerations. View full abstract»

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  • Current and future trends of biologically inspired underwater vehicles

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1672 KB) |  | HTML iconHTML  

    The combination of biological principles, mechanical engineering, and robotics has opened up an entirely new area and possibility. In addition to those works from active and prominent groups in the international biomimetics community on bio inspired aquatic robots, recent research and development works on underwater robotics by the NTU team will be presented in this paper. The bio-inspired fin design on the underwater vehicles will be illustrated together with the concept of modular mechanism segments. The specified fin mechanical layout is able to produce a wide range of motions in various modes. Some swimming test results of the finned robots will be briefly shown. Design issues and challenges towards the effective implementation in terms of energy. The discussion on biological inspired underwater vehicles comes at a particularly appropriate time when activity in the area of biomimetics is increasing. This paper should also act as a good introduction to engineers and technologists might not be familiar to the fields. View full abstract»

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  • The continuing learning curve from airliner failure

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (156 KB) |  | HTML iconHTML  

    The military situation is almost invariably at the "sharp end" of technology where aircraft fly faster, have tighter design margins, heavier loads, more sophisticated software and maybe no pilot at all. Failure cause and effect is usually classified for security reasons, so we have to look at the civil airliner situation for an overview of what things can cause accidents. Here the international airline safety authorities, their national equivalents, the airline operators and the aircraft manufacturers all seek careful analyses of why and how things actually went wrong. View full abstract»

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  • The research on the astronauts operation sEMG based on small sample data analysis

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (205 KB) |  | HTML iconHTML  

    Under the extremely limited space experimental conditions, it's still a challenge for us to make the small sample of the data ensure the validity of experimental results in a certain confidence interval. We used the theory of small sample data analysis to design and synthesize strategies in order to be adequate for reasonably good knockdown of the number of samples required for the experiment. And we applied and verified the method to determine the number of operation sEMG signal samples by using an example of space ergonomics experiment. Finally, we analyzed the applicability and reliability of this method for series of experiments and looked forward to the trend of the research directions. View full abstract»

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  • The air ion mobility spectra of corona air ionization

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (142 KB) |  | HTML iconHTML  

    The article considers electrical mobility spectra of small and intermediate air ions as a result of corona air ionization. The generation of intermediate air ions, which are charged nanoparticles, is detected near the corona ionizer. The modifications of air ion spectra from distance to corona air ionizer are presented. The probable ways of intermediate air ion formation are discussed. View full abstract»

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  • Measurement of field blast testing data using high speed data acquisition system for steel fiber reinforced concrete

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (456 KB) |  | HTML iconHTML  

    This paper reports on a measurement of field blast testing data for steel fiber reinforced concrete using high speed data acquisition system. In this experiment a field blast test was conducted by the Blast Research Unit of University Pertahanan Nasional Malaysia to investigate the behavior of steel fiber reinforced concrete panel subjected to air blast loading. The steel fiber reinforced concrete panels were subjected to air blast loading using plastic explosive (PE4) weighing 1kg each at standoff distance of 0.3 meter. The parameters measured are air blast pressure, free field blast pressure and also acceleration of the slab using high speed data acquisition system and the result is presented in this paper. View full abstract»

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  • Acoustic tool to test status of respiratory ventilation function

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (150 KB) |  | HTML iconHTML  

    Diving renders negative influence on human respiratory system especially when oxygen breathing apparatus aimed for military divers is used. Spirometry indexes have poor sensitivity to toxic effect of hyperbaric hyperoxia. Objective is to develop new acoustic instrumentation for revealing minimum impairments of lung function in oxygen divers. The apparatus has been designed which is based on analysis of forced expiratory tracheal noise duration (FETND). This apparatus contains acoustic sensor, input device, portable personal computer and specially designed software. 48 divers before and after single shallow water dive in oxygen closed-type breathing apparatus were tested by means of this acoustic tool. After dive a significant drop of spirometric indexes forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1) over the group as a whole was found. The significant increase of individual FETND, exceeding the natural variability limit, was found in 10 subjects (20.8%). Three of them during dive had respiratory symptoms characteristic for initial manifestations of pulmonary oxygen poisoning. Two of them had essential drop of FEV1. The asymptomatic reversible increase of FETND in the rest 7 divers was interpreted as a sign of obstructive impairments caused by hidden phase of hyperbaric hyperoxia effect. Thus developed acoustic tool is useful to monitor ventilation function of lungs in military/civil divers and other persons working in harmful gas media such as firefighters, astronauts and so on. View full abstract»

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