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Sample records for non-invasive optical characterization

  1. Tissue Damage Characterization Using Non-invasive Optical Modalities

    NASA Astrophysics Data System (ADS)

    Diaz, David

    The ability to determine the degree of cutaneous and subcutaneous tissue damage is essential for proper wound assessment and a significant factor for determining patient treatment and morbidity. Accurate characterization of tissue damage is critical for a number of medical applications including surgical removal of nonviable tissue, severity assessment of subcutaneous ulcers, and depth assessment of visually open wounds. The main objective of this research was to develop a non-invasive method for identifying the extent of tissue damage underneath intact skin that is not apparent upon visual examination. This work investigated the relationship between tissue optical properties, blood flow, and tissue viability by testing the hypotheses that (a) changes in tissue oxygenation and/or microcirculatory blood flow measurable by Diffuse Near Infrared Spectroscopy (DNIRS) and Diffuse Correlation Spectroscopy (DCS) differ between healthy and damaged tissue and (b) the magnitude of those changes differs for different degrees of tissue damage. This was accomplished by developing and validating a procedure for measuring microcirculatory blood flow and tissue oxygenation dynamics at multiple depths (up to 1 centimeter) using non-invasive DCS and DNIRS technologies. Due to the lack of pressure ulcer animal models that are compatible with our optical systems, a proof of concept was conducted in a porcine burn model prior to conducting clinical trials in order to assess the efficacy of the system in-vivo. A reduction in total hemoglobin was observed for superficial (5%) and deep burns (35%) along with a statistically significant difference between the optical properties of superficial and deep burns (p < 0.05). Burn depth and viable vessel density were estimated via histological samples. 42% of vessels in the dermal layer were viable for superficial burns, compared to 25% for deep burns. The differences detected in optical properties and hemoglobin content by optical measurements

  2. Non-invasive optical characterization of biomaterial mineralization.

    PubMed

    Gupta, Sharad; Hunter, Martin; Cebe, Peggy; Levitt, Jonathan M; Kaplan, David L; Georgakoudi, Irene

    2008-05-01

    Current approaches to study biomaterial mineralization are invasive and prevent dynamic characterization of this process within the same sample. Polarized light scattering spectroscopy (LSS) may offer a non-invasive alternative for assessing the levels of mineralization as well as some aspects of the organization of the mineral deposits. Specifically, we used LSS to characterize the formation of hydroxyapatite deposits on three types of silk films (water-annealed, methanol-treated and polyaspartic acid (PAA)-mixed) following 1, 3, 5 and 7 cycles of mineralization. We found that the total light scattering intensity provided a quantitative measure of the degree of mineralization as confirmed by thermal gravimetric analysis (TGA). The PAA-mixed silk films yielded the highest level of mineral deposition and the water-annealed ones the least, consistent with the beta sheet content of the films prior to the onset of mineralization. The wavelength dependence of the singly backscattered light was consistent with a self-affine fractal morphology of the deposited films within scales in the range of 150-300nm; this was confirmed by Fourier analysis of scanning electron microscopy (SEM) images of the corresponding films. The deposits of minerals in the water-annealed films were predominantly flake-like, with positively correlated density fluctuations (Hurst parameter, H>0.5), whereas methanol-treated and PAA-mixed silk films resulted in densely-packed, bulk mineral deposits with negatively correlated density fluctuations (H<0.5). Therefore, LSS could serve as a valuable tool for understanding the role of biomaterial properties in mineral formation, and, ultimately, for optimizing biomaterial designs that yield mineral deposits with the desired organization. PMID:18313137

  3. Towards non-invasive characterization of breast cancer and cancer metabolism with diffuse optics

    PubMed Central

    Busch, David R.; Choe, Regine; Durduran, Turgut; Yodh, Arjun G.

    2013-01-01

    We review recent developments in diffuse optical imaging and monitoring of breast cancer, i.e. optical mammography. Optical mammography permits non-invasive, safe and frequent measurement of tissue hemodynamics oxygen metabolism and components (lipids, water, etc.), the development of new compound indices indicative of the risk and malignancy, and holds potential for frequent non-invasive longitudinal monitoring of therapy progression. PMID:24244206

  4. Optical non-invasive 3D characterization of pottery of pre-colonial Paranaiba valley tribes

    NASA Astrophysics Data System (ADS)

    Magalhães, Wagner; Alves, Márcia Angelina; Costa, Manuel F.

    2014-08-01

    Optical non-invasive inspection tools and methods had expensively proven, for several decades now, their invaluable importance in the preservation of cultural heritage and artwork. In this paper we will report on an optical non-invasive microtopographic characterization work on pre-historical and pre-colonial ceramics and pottery of tribes in the Paranaiba valley in Minas Gerais, Brazil. The samples object of this work were collected at the Inhazinha archeological site (19º 10'00" S / 47° 11'00" W) in the vicinity of Perdizes municipality in transition between the West mining area and the "triangle" area in the center of Brazil. It is a hilly region (850m high) traversed by a number of rivers and streams tributary of Araguari river like Quebra Anzol river and Macaúba and Olegário streams. The Inhazinha site' excavations are part of the Project Jigsaw Hook which since 1980 aimed the establishment of a chrono-cultural framework associated with the study of the socio-cultural dynamics corresponding to successive occupations of hunter-recollector-farmer' tribes in prehistoric and pre-colonial times in the Paranaíba valley in Minas Gerais, Brazil. Two groups of indigenous Indian occupations were found. Both of the pre-colonial period dated at 1,095 ± 186 years ago (TL-FATEC/SP for Zone 1) and of the early nineteenth century dated at 212 ± 19 years ago (EMS-CENA-USP/SP) and 190 ± 30 years ago (C14- BETA/USA) in Zone 2 seemingly occupied by southern Kayapós tribes. The pottery found is decorated with incisions with different geometric distributions and levels of complexity.

  5. The potential of label-free nonlinear optical molecular microscopy to non-invasively characterize the viability of engineered human tissue constructs.

    PubMed

    Chen, Leng-Chun; Lloyd, William R; Kuo, Shiuhyang; Kim, Hyungjin Myra; Marcelo, Cynthia L; Feinberg, Stephen E; Mycek, Mary-Ann

    2014-08-01

    Nonlinear optical molecular imaging and quantitative analytic methods were developed to non-invasively assess the viability of tissue-engineered constructs manufactured from primary human cells. Label-free optical measures of local tissue structure and biochemistry characterized morphologic and functional differences between controls and stressed constructs. Rigorous statistical analysis accounted for variability between human patients. Fluorescence intensity-based spatial assessment and metabolic sensing differentiated controls from thermally-stressed and from metabolically-stressed constructs. Fluorescence lifetime-based sensing differentiated controls from thermally-stressed constructs. Unlike traditional histological (found to be generally reliable, but destructive) and biochemical (non-invasive, but found to be unreliable) tissue analyses, label-free optical assessments had the advantages of being both non-invasive and reliable. Thus, such optical measures could serve as reliable manufacturing release criteria for cell-based tissue-engineered constructs prior to human implantation, thereby addressing a critical regulatory need in regenerative medicine. PMID:24854093

  6. An optical approach for non-invasive blood clot testing

    NASA Astrophysics Data System (ADS)

    Kalchenko, Vyacheslav; Brill, Alexander; Fine, Ilya; Harmelin, Alon

    2007-02-01

    Physiological blood coagulation is an essential biological process. Current tests for plasma coagulation (clotting) need to be performed ex vivo and require fresh blood sampling for every test. A recently published work describes a new, noninvasive, in vivo approach to assess blood coagulation status during mechanical occlusion1. For this purpose, we have tested this approach and applied a controlled laser beam to blood micro-vessels of the mouse ear during mechanical occlusion. Standard setup for intravital transillumination videomicroscopy and laser based imaging techniques were used for monitoring the blood clotting process. Temporal mechanical occlusion of blood vessels in the observed area was applied to ensure blood flow cessation. Subsequently, laser irradiation was used to induce vascular micro-injury. Changes in the vessel wall, as well as in the pattern of blood flow, predispose the area to vascular thrombosis, according to the paradigm of Virchow's triad. In our experiments, two elements of Virchow's triad were used to induce the process of clotting in vivo, and to assess it optically. We identified several parameters that can serve as markers of the blood clotting process in vivo. These include changes in light absorption in the area of illumination, as well as changes in the pattern of the red blood cells' micro-movement in the vessels where blood flow is completely arrested. Thus, our results indicate that blood coagulation status can be characterized by non-invasive, in vivo methodologies.

  7. Non-Invasive Optical Biosensor for Probing Cell Signaling

    PubMed Central

    Fang, Ye

    2007-01-01

    Cell signaling mediated through a cellular target is encoded by spatial and temporal dynamics of downstream signaling networks. The coupling of temporal dynamics with spatial gradients of signaling activities guides cellular responses upon stimulation. Monitoring the integration of cell signaling in real time, if realized, would provide a new dimension for understanding cell biology and physiology. Optical biosensors including resonant waveguide grating (RWG) biosensor manifest a physiologically relevant and integrated cellular response related to dynamic redistribution of cellular matters, thus providing a non-invasive means for cell signaling study. This paper reviews recent progresses in biosensor instrumentation, and theoretical considerations and potential applications of optical biosensors for whole cell sensing.

  8. Neurophotonics: non-invasive optical techniques for monitoring brain functions.

    PubMed

    Torricelli, Alessandro; Contini, Davide; Dalla Mora, Alberto; Pifferi, Antonio; Re, Rebecca; Zucchelli, Lucia; Caffini, Matteo; Farina, Andrea; Spinelli, Lorenzo

    2014-01-01

    The aim of this review is to present the state of the art of neurophotonics, a recently founded discipline lying at the interface between optics and neuroscience. While neurophotonics also includes invasive techniques for animal studies, in this review we focus only on the non-invasive methods that use near infrared light to probe functional activity in the brain, namely the fast optical signal, diffuse correlation spectroscopy, and functional near infrared spectroscopy methods. We also present an overview of the physical principles of light propagation in biological tissues, and of the main physiological sources of signal. Finally, we discuss the open issues in models, instrumentation, data analysis and clinical approaches. PMID:25764252

  9. Neurophotonics: non-invasive optical techniques for monitoring brain functions

    PubMed Central

    Torricelli, Alessandro; Contini, Davide; Mora, Alberto Dalla; Pifferi, Antonio; Re, Rebecca; Zucchelli, Lucia; Caffini, Matteo; Farina, Andrea; Spinelli, Lorenzo

    2014-01-01

    Summary The aim of this review is to present the state of the art of neurophotonics, a recently founded discipline lying at the interface between optics and neuroscience. While neurophotonics also includes invasive techniques for animal studies, in this review we focus only on the non-invasive methods that use near infrared light to probe functional activity in the brain, namely the fast optical signal, diffuse correlation spectroscopy, and functional near infrared spectroscopy methods. We also present an overview of the physical principles of light propagation in biological tissues, and of the main physiological sources of signal. Finally, we discuss the open issues in models, instrumentation, data analysis and clinical approaches. PMID:25764252

  10. Influence of hemoglobin on non-invasive optical bilirubin sensing

    NASA Astrophysics Data System (ADS)

    Jiang, Jingying; Gong, Qiliang; Zou, Da; Xu, Kexin

    2012-03-01

    Since the abnormal metabolism of bilirubin could lead to diseases in the human body, especially the jaundice which is harmful to neonates. Traditional invasive measurements are difficult to be accepted by people because of pain and infection. Therefore, the real-time and non-invasive measurement of bilirubin is of great significance. However, the accuracy of currently transcutaneous bilirubinometry(TcB) is generally not high enough, and affected by many factors in the human skin, mostly by hemoglobin. In this talk, absorption spectra of hemoglobin and bilirubin have been collected and analyzed, then the Partial Least Squares (PLS) models have been built. By analyzing and comparing the Correlation and Root Mean Square Error of Prediction(RMSEP), the results show that the Correlation of bilirubin solution model is larger than that of the mixture solution added with hemoglobin, and its RMSEP value is smaller than that of mixture solution. Therefore, hemoglobin has influences on the non-invasive optical bilirubin sensing. In next step, it is necessary to investigate how to eliminate the influence.

  11. Application of optical non-invasive methods in skin physiology

    NASA Astrophysics Data System (ADS)

    Lademann, J.; Patzelt, A.; Darvin, M.; Richter, H.; Antoniou, C.; Sterry, W.; Koch, S.

    2008-05-01

    In the present paper the application of optical non-invasive methods in dermatology and cosmetology is discussed. Laser scanning microscopy (LSM) and optical coherent tomography (OCT) are the most promising methods for this application. Using these methods, the analysis of different skin parameters like dryness and oiliness of the skin, the barrier function and the structure of furrows and wrinkles are discussed. Additionally the homogeneity of distribution of topically applied creams, as well as their penetration into the skin were investigated. It is shown that these methods are highly valuable in dermatology for diagnostic and therapy control and for basic research, for instance in the field of structure analysis of hair follicles and sweat glands. The vertical images of the tissue produced by OCT can be easily compared with histological sections. Unfortunately, the resolution of the OCT technique is not high enough to carry out measurements on a cellular level, as is possible by LSM. LSM has the advantage that it can be used for the investigation of penetration and storage processes of topically applied substances, if these substances have fluorescent properties or if they are fluorescent-labelled.

  12. Non-invasive Optical Molecular Imaging for Cancer Detection

    NASA Astrophysics Data System (ADS)

    Luo, Zhen

    Cancer is a leading cause of death worldwide. It remains the second most common cause of death in the US, accounting for nearly 1 out of every 4 deaths. Improved fundamental understanding of molecular processes and pathways resulting in cancer development has catalyzed a shift towards molecular analysis of cancer using imaging technologies. It is expected that the non-invasive or minimally invasive molecular imaging analysis of cancer can significantly aid in improving the early detection of cancer and will result in reduced mortality and morbidity associated with the disease. The central hypothesis of the proposed research is that non-invasive imaging of changes in metabolic activity of individual cells, and extracellular pH within a tissue will improve early stage detection of cancer. The specific goals of this research project were to: (a) develop novel optical imaging probes to image changes in choline metabolism and tissue pH as a function of progression of cancer using clinically isolated tissue biopsies; (b) correlate changes in tissue extracellular pH and metabolic activity of tissues as a function of disease state using clinically isolated tissue biopsies; (c) provide fundamental understanding of relationship between tumor hypoxia, acidification of the extracellular space and altered cellular metabolism with progression of cancer. Three novel molecular imaging probes were developed to detect changes in choline and glucose metabolism and extracellular pH in model systems and clinically isolated cells and biopsies. Glucose uptake and metabolism was measured using a fluorescence analog of glucose, 2-NBDG (2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-D-glucose), while choline metabolism was measured using a click chemistry analog of choline, propargyl choline, which can be in-situ labeled with a fluorophore Alexa-488 azide via a click chemistry reaction. Extracellular pH in tissue were measured by Alexa-647 labeled pHLIP (pH low insertion peptide

  13. Optical non-invasive monitoring of skin blood pulsations

    NASA Astrophysics Data System (ADS)

    Spīgulis, Jānis

    2005-08-01

    Time resolved detection and analysis of the skin backscattered optical signals (remission photoplethysmography or PPG) provide rich information on skin blood volume pulsations and can serve for reliable cardiovascular assessment. The single- and multi-channel PPG concepts are discussed in this work. Simultaneous data flow from several body locations allows one to study the heartbeat pulse wave propagation in real time and evaluate the vascular resistance. Portable single-, dual- and four-channel PPG monitoring devices with special software have been designed for real-time data acquisition and processing. The clinical studies confirmed their potential in the monitoring of heart arrhythmias, drug tests, steady-state cardiovascular assessment, body fitness control, and express diagnostics of the arterial occlusions.

  14. Non-invasive optical detection of glucose in cell culture nutrient medium

    NASA Technical Reports Server (NTRS)

    Cote, Gerald L.

    1993-01-01

    The objective of the proposed research was to begin the development of a non-invasive optical sensor for measuring glucose concentration in the output medium of cell cultures grown in a unique NASA bioreactor referred to as an integrated rotating-wall vessel (IRWV). The input, a bovine serum based nutrient media, has a known glucose concentration. The cells within the bioreactor digest a portion of the glucose. Thus, the non-invasive optical sensor is needed to monitor the decrease in glucose due to cellular consumption since the critical parameters for sustained cellular productivity are glucose and pH. Previous glucose sensing techniques have used chemical reactions to quantify the glucose concentration. Chemical reactions, however, cannot provide for continuous, real time, non-invasive measurement as is required in this application. Our effort while in the fellowship program was focused on the design, optical setup, and testing of one bench top prototype non-invasive optical sensor using a mid-infrared absorption spectroscopy technique. Glucose has a fundamental vibrational absorption peak in the mid-infrared wavelength range at 9.6 micron. Preliminary absorption data using a CO2 laser were collected at this wavelength for water based glucose solutions at different concentrations and one bovine serum based nutrient medium (GTSF) with added glucose. The results showed near linear absorption responses for the glucose-in-water data with resolutions as high at 108 mg/dl and as low as 10 mg/dl. The nutrient medium had a resolution of 291 mg/dl. The variability of the results was due mainly to thermal and polarization drifts of the laser while the decrease in sensitivity to glucose in the nutrient medium was expected due to the increase in the number of confounders present in the nutrient medium. A multispectral approach needs to be used to compensate for these confounders. The CO2 laser used for these studies was wavelength tunable (9.2 to 10.8 micrometers), however

  15. Non-Invasive Multi-Dimensional Two-Photon Microscopy enables optical fingerprinting (TPOF) of immune cells.

    PubMed

    Gehlsen, Uta; Szaszák, Marta; Gebert, Andreas; Koop, Norbert; Hüttmann, Gereon; Steven, Philipp

    2015-06-01

    Mucosal surfaces are constantly exposed to pathogens and show high immunological activity. In a broad variety of ocular surface disorders inflammation is common, but underlying mechanisms are often not fully understood. However, the main clinical problem is that inflammatory processes are difficult to characterize and quantify due to the impossibility of repeated tissue probing of the delicate ocular surface. Therefore non-invasive optical methods are thought to have the potential for intravital investigation of ocular surface inflammation. This study demonstrates the general potential of two-photon microscopy to non-invasively detect and discriminate key players of inflammation in the ocular surface by using intrinsic fluorescence-based features without the necessity of tissue probing or the use of dyes. The use of wavelength dependent measurements of fluorescence lifetime, in addition to autofluorescence intensity enables a functional differentiation of isolated immune cells in vitro at excitation wavelengths between 710 to 830 nm. Mixed cell cultures and first in vivo results indicate the use of excitation wavelength of 710 to 750 nm for further experiments and future use in patients. Two photon based autofluorescence features of immune cells enables non-invasive differentiation. PMID:25186637

  16. Non-invasive measurements of tissue hemodynamics with hybrid diffuse optical methods

    NASA Astrophysics Data System (ADS)

    Durduran, Turgut

    Diffuse optical techniques were used to measure hemodynamics of tissues non-invasively. Spectroscopy and tomography of the brain, muscle and implanted tumors were carried out in animal models and humans. Two qualitatively different methods, diffuse optical tomography and diffuse correlation tomography, were hybridized permitting simultaneous measurement of total hemoglobin concentration, blood oxygen saturation and blood flow. This combination of information was processed further to derive estimates of oxygen metabolism (e.g. CMRO 2) in tissue. The diffuse correlation measurements of blood flow were demonstrated in human tissues, for the first time, demonstrating continous, non-invasive imaging of oxygen metabolism in large tissue volumes several centimeters below the tissue surface. The bulk of these investigations focussed on cerebral hemodynamics. Extensive validation of this methodology was carried out in in vivo rat brain models. Three dimensional images of deep tissue hemodynamics in middle cerebral artery occlusion and cortical spreading depression (CSD) were obtained. CSD hemodynamics were found to depend strongly on partial pressure of carbon dioxide. The technique was then adapted for measurement of human brain. All optical spectroscopic measurements of CMRO2 during functional activation were obtained through intact human skull non-invasively. Finally, a high spatio-temporal resolution measurement of cerebral blood flow due to somatosensory cortex activation following electrical forepaw stimulation in rats was carried out with laser speckle flowmetry. New analysis methods were introduced for laser speckle flowmetry. In other organs, deep tissue hemodynamics were measured on human calf muscle during exercise and cuff-ischemia and were shown to have some clinical utility for peripheral vascular disease. In mice tumor models, the measured hemodynamics were shown to be predictive of photodynamic therapy efficacy, again suggesting promise of clinical utility

  17. A simple approach for non-invasive transcranial optical vascular imaging (nTOVI).

    PubMed

    Kalchenko, Vyacheslav; Israeli, David; Kuznetsov, Yuri; Meglinski, Igor; Harmelin, Alon

    2015-11-01

    In vivo imaging of cerebral vasculature is highly vital for clinicians and medical researchers alike. For a number of years non-invasive optical-based imaging of brain vascular network by using standard fluorescence probes has been considered as impossible. In the current paper controverting this paradigm, we present a robust non-invasive optical-based imaging approach that allows visualize major cerebral vessels at the high temporal and spatial resolution. The developed technique is simple to use, utilizes standard fluorescent dyes, inexpensive micro-imaging and computation procedures. The ability to clearly visualize middle cerebral artery and other major vessels of brain vascular network, as well as the measurements of dynamics of blood flow are presented. The developed imaging approach has a great potential in neuroimaging and can significantly expand the capabilities of preclinical functional studies of brain and notably contribute for analysis of cerebral blood circulation in disorder models. An example of 1 × 1.5 cm color-coded image of brain blood vessels of mouse obtained in vivo by transcranial optical vascular imaging (TOVI) approach through the intact cranium. PMID:25924020

  18. Fibre optic sensor for non-invasive monitoring of blood pressure during MRI scanning.

    PubMed

    Myllylä, Teemu S; Elseoud, Ahmed Abou; Sorvoja, Hannu S S; Myllylä, Risto A; Harja, Juha M; Nikkinen, Juha; Tervonen, Osmo; Kiviniemi, Vesa

    2011-01-01

    This report focuses on designing and implementing a non-invasive blood pressure (NIBP) measuring device capable of being used during magnetic resonance imaging (MRI). Based on measuring pulse wave velocity in arterial blood, the device uses the obtained result to estimate diastolic blood pressure. Pulse transit times are measured by two fibre optical accelerometers placed over the chest and carotid artery. The fabricated accelerometer contains two static fibres and a cantilever beam, whose free end is angled at 90 degrees to act as a reflecting surface. Optical fibres are used for both illuminating the surface and receiving the reflected light. When acceleration is applied to the sensor, it causes a deflection in the beam, thereby changing the amount of reflected light. The sensor's output voltage is proportional to the intensity of the reflected light. Tests conducted on the electronics and sensors inside an MRI room during scanning proved that the device is MR- compatible. No artifacts or distortions were detected. PMID:20401906

  19. The importance of optical methods for non-invasive measurements in the skin care industry

    NASA Astrophysics Data System (ADS)

    Stamatas, Georgios N.

    2010-02-01

    Pharmaceutical and cosmetic industries are concerned with treating skin disease, as well as maintaining and promoting skin health. They are dealing with a unique tissue that defines our body in space. As such, skin provides not only the natural boundary with the environment inhibiting body dehydration as well as penetration of exogenous aggressors to the body, it is also ideally situated for optical measurements. A plurality of spectroscopic and imaging methods is being used to understand skin physiology and pathology and document the effects of topically applied products on the skin. The obvious advantage of such methods over traditional biopsy techniques is the ability to measure the cutaneous tissue in vivo and non-invasively. In this work, we will review such applications of various spectroscopy and imaging methods in skin research that is of interest the cosmetic and pharmaceutical industry. Examples will be given on the importance of optical techniques in acquiring new insights about acne pathogenesis and infant skin development.

  20. Speckle contrast optical spectroscopy, a non-invasive, diffuse optical method for measuring microvascular blood flow in tissue

    PubMed Central

    Valdes, Claudia P.; Varma, Hari M.; Kristoffersen, Anna K.; Dragojevic, Tanja; Culver, Joseph P.; Durduran, Turgut

    2014-01-01

    We introduce a new, non-invasive, diffuse optical technique, speckle contrast optical spectroscopy (SCOS), for probing deep tissue blood flow using the statistical properties of laser speckle contrast and the photon diffusion model for a point source. The feasibility of the method is tested using liquid phantoms which demonstrate that SCOS is capable of measuring the dynamic properties of turbid media non-invasively. We further present an in vivo measurement in a human forearm muscle using SCOS in two modalities: one with the dependence of the speckle contrast on the source-detector separation and another on the exposure time. In doing so, we also introduce crucial corrections to the speckle contrast that account for the variance of the shot and sensor dark noises. PMID:25136500

  1. Muscle tissue saturation in humans studied with two non-invasive optical techniques: a comparative study

    NASA Astrophysics Data System (ADS)

    Shaharin, Alfi; Krite Svanberg, Emilie; Ellerström, Ida; Subash, Arman Ahamed; Khoptyar, Dmitry; Andersson-Engels, Stefan; Åkeson, Jonas

    2013-11-01

    Muscle tissue saturation (StO2) has been measured with two non-invasive optical techniques and the results were compared. One of the techniques is widely used in the hospitals - the CW-NIRS technique. The other is the photon timeof- flight spectrometer (pTOFS) developed in the Group of Biophotonics, Lund University, Sweden. The wavelengths used in both the techniques are 730 nm and 810 nm. A campaign was arranged to perform measurements on 21 (17 were taken for comparison) healthy adult volunteers (8 women and 13 men). Oxygen saturations were measured at the right lower arm of each volunteer. To observe the effects of different provocations on the oxygen saturation a blood pressure cuff was attached in the upper right arm. For CW-NIRS, the tissue saturation values were in the range from 70-90%, while for pTOFS the values were in the range from 55-60%.

  2. Feasibility of optical diffraction radiation for a non-invasive low-emittance beam diagnostics

    NASA Astrophysics Data System (ADS)

    Urakawa, J.; Hayano, H.; Kubo, K.; Kuroda, S.; Terunuma, N.; Kuriki, M.; Okugi, T.; Naito, T.; Araki, S.; Potylitsyn, A.; Naumenko, G.; Karataev, P.; Potylitsyna, N.; Vnukov, I.; Hirose, T.; Hamatsu, R.; Muto, T.; Ikezawa, M.; Shibata, Y.

    2001-10-01

    A "proof-of-principle" experiment on the optical diffraction radiation (ODR) as a single-pulse beam profile monitor is planned using an electron beam extracted from the KEK-ATF damping ring. The main goals of this experiment are the following: (i) To measure the yield and the angular distributions of the optical diffraction radiation from a large-size target at different wavelengths, impact parameters and beam characteristics for a comparison with analogous characteristics of optical transition radiation from a foil with identical optical parameters and for a verification of the model assumption (perfectly conducting semi-infinite target). (ii) To investigate the ODR angular distributions from a tilted target with a slit for observing the interference effects. (iii) To compare the results obtained by simulations based on classical approaches, taking into account the optical characteristics of the equipment and the beam parameters. (iv) To estimate the prospects of using ODR as a new non-invasive tool for ultrarelativistic beams. We estimated that the ODR photon yield in 10% bandwidth for 500 nm is about 10 6 photons/bunch with an impact parameter of 100 μm. This indicates that the ODR monitor is a promising candidate for single-pulse beam-profile measurements, and that it will be an extremely useful instrument for future linear colliders (JLC, NLC, TESLA and CLIC).

  3. Non-invasive detection of periodontal loss of attachment using optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Damodaran, Vani; Vasa, Nilesh J.; Sarathi, R.; Rao, Suresh Ranga

    2015-06-01

    This study aims at developing a non-invasive technique to evaluate periodontal loss of attachment in the oral cavity. A method of imaging periodontal loss of attachment based on time-domain optical coherence tomography is proposed and studied. Based on measurements, boundaries of gingival tissue and tooth were seen separated by ≈0.3 mm. Further study is in progress to image the anatomical landmarks and evaluate the periodontal loss of attachment. The conventional time domain OCT systems acquisition speed is limited by the speed of the mechanical scanning system. In order to overcome this issue, a novel electro-optic based scanning system is proposed and demonstrated. Studies were performed initially with lithium niobate and potassium titanyl phosphate crystals and the tuning range observed were low. In order to increase the tuning range, a crystal with high electro-optic coefficient - potassium tantalite niobate was identified and experiments were carried out to characterise the crystal and electro-optic based phase tuning is demonstrated.

  4. Non-invasive characterization of intracranial tumors by magnetic resonance elastography

    NASA Astrophysics Data System (ADS)

    Simon, M.; Guo, J.; Papazoglou, S.; Scholand-Engler, H.; Erdmann, C.; Melchert, U.; Bonsanto, M.; Braun, J.; Petersen, D.; Sack, I.; Wuerfel, J.

    2013-08-01

    Presurgical, non-invasive methods of differentiating brain tumors have remained unsatisfactory even for specialized academic hospitals. Despite major advances in clinical and neuroradiological diagnostic techniques, the majority of neurooncology patients still need to undergo a brain biopsy for diagnosis. Recent single cell experiments suggested that biomechanical cell properties might be very sensitive in detecting cellular malignancy. Accordingly, we investigated magnetic resonance elastography (MRE) as an investigative tool for the clinical routine diagnostic work-up of intracranial neoplasm. In order to obtain sufficient spatial resolution for the biomechanical characterization of intracranial tumors, we modified a recently introduced least-squares solution of the stationary wave equation, facilitating stable solutions of the magnitude |G*| and the phase angle φ of the complex shear modulus G*. MRE was added to a routine diagnostic or presurgical neuroradiological magnetic resonance imaging work-up in 16 prospective patients and it was well tolerated in all cases. Our preliminary tumor MRE data revealed alterations in viscoelastic constants, e.g. a loss of stiffness in malignancies compared to healthy reference tissue, or benign variants. Based on larger studies on selected tumor entities to establish threshold and reference values for future diagnostic purposes, MRE may thus provide a predictive marker for tumor malignancy and thereby contribute to an early non-invasive clinical assessment of suspicious cerebral lesions.

  5. Multiscattering-enhanced optical biosensor: multiplexed, non-invasive and continuous measurements of cellular processes

    PubMed Central

    Koman, Volodymyr B.; Santschi, Christian; Martin, Olivier J. F.

    2015-01-01

    The continuous measurement of uptake or release of biomarkers provides invaluable information for understanding and monitoring the metabolism of cells. In this work, a multiscattering-enhanced optical biosensor for the multiplexed, non-invasive, and continuous detection of hydrogen peroxide (H2O2), lactate and glucose is presented. The sensing scheme is based on optical monitoring of the oxidation state of the metalloprotein cytochrome c (cyt c). The analyte of interest is enzymatically converted into H2O2 leading to an oxidation of the cyt c. Contact microspotting is used to prepare nanoliter-sized sensing spots containing either pure cyt c, a mixture of cyt c with glucose oxidase (GOx) to detect glucose, or a mixture of cyt c with lactate oxidase (LOx) to detect lactate. The sensing spots are embedded in a multiscattering porous medium that enhances the optical signal. We achieve limits of detection down to 240 nM and 110 nM for lactate and glucose, respectively. A microfluidic embodiment enables multiplexed and crosstalk-free experiments on living organisms. As an example, we study the uptake of exogenously supplied glucose by the green algae Chlamydomonas reinhardtii and simultaneously monitor the stress-related generation of H2O2. This multifunctional detection scheme provides a powerful tool to study biochemical processes at cellular level. PMID:26203366

  6. Multiscattering-enhanced optical biosensor: multiplexed, non-invasive and continuous measurements of cellular processes.

    PubMed

    Koman, Volodymyr B; Santschi, Christian; Martin, Olivier J F

    2015-07-01

    The continuous measurement of uptake or release of biomarkers provides invaluable information for understanding and monitoring the metabolism of cells. In this work, a multiscattering-enhanced optical biosensor for the multiplexed, non-invasive, and continuous detection of hydrogen peroxide (H2O2), lactate and glucose is presented. The sensing scheme is based on optical monitoring of the oxidation state of the metalloprotein cytochrome c (cyt c). The analyte of interest is enzymatically converted into H2O2 leading to an oxidation of the cyt c. Contact microspotting is used to prepare nanoliter-sized sensing spots containing either pure cyt c, a mixture of cyt c with glucose oxidase (GOx) to detect glucose, or a mixture of cyt c with lactate oxidase (LOx) to detect lactate. The sensing spots are embedded in a multiscattering porous medium that enhances the optical signal. We achieve limits of detection down to 240 nM and 110 nM for lactate and glucose, respectively. A microfluidic embodiment enables multiplexed and crosstalk-free experiments on living organisms. As an example, we study the uptake of exogenously supplied glucose by the green algae Chlamydomonas reinhardtii and simultaneously monitor the stress-related generation of H2O2. This multifunctional detection scheme provides a powerful tool to study biochemical processes at cellular level. PMID:26203366

  7. Non-invasive characterization of fluid foodstuffs based on ultrasonic measurements

    SciTech Connect

    Bamberger, Judith A.; Greenwood, Margaret S.

    2004-07-01

    The food industry can benefit from a highly sensitive, non-invasive, self-calibrating, on-line sensor for characterizing liquid or slurry in process vessels during mixing, settling, stationary, or flowing conditions by measuring the density, sound speed, and attenuation of ultrasound. The sensor system was developed by staff at Pacific Northwest National Laboratory. The sensor transducers are mounted directly on the stainless steel wall and the pipeline wall becomes part of the measurement system. Multiple reflections within the stainless steel wall are used to determine the acoustic impedance of the liquid, where the acoustic impedance is defined as the product of the density and the speed of sound. The probe becomes self-calibrating because variations in the pulser voltage do not affect the measurements. By basing the measurement upon multiple reflections, the sensitivity of the measurement is significantly increased

  8. Quantitative molecular characterization of bovine vitreous and lens with non-invasive dynamic light scattering

    NASA Technical Reports Server (NTRS)

    Ansari, R. R.; Suh, K. I.; Dunker, S.; Kitaya, N.; Sebag, J.

    2001-01-01

    The non-invasive technique of dynamic light scattering (DLS) was used to quantitatively characterize vitreous and lens structure on a molecular level by measuring the sizes of the predominant particles and mapping the three-dimensional topographic distribution of these structural macromolecules in three spatial dimensions. The results of DLS measurements in five fresh adult bovine eyes were compared to DLS measurements in model solutions of hyaluronan (HA) and collagen (Coll). In the bovine eyes DLS measurements were obtained from excised samples of gel and liquid vitreous and compared to the model solutions. Measurements in whole vitreous were obtained at multiple points posterior to the lens to generate a three-dimensional 'map' of molecular structure. The macromolecule distribution in bovine lens was similarly characterized.In each bovine vitreous (Bo Vit) specimen, DLS predominantly detected two distinct particles, which differed in diffusion properties and hence size. Comparisons with model vitreous solutions demonstrated that these most likely corresponded to the Coll and HA components of vitreous. Three-dimensional mapping of Bo Vit found heterogeneity throughout the vitreous body, with different particle size distributions for Coll and HA at different loci. In contrast, the three-dimensional distribution of lens macromolecules was more homogeneous. Thus, the non-invasive DLS technique can quantitate the average sizes of vitreous and lens macromolecules and map their three-dimensional distribution. This method to assess quantitatively the macromolecular structure of vitreous and lens should be useful for clinical as well as experimental applications in health and disease. Copyright 2001 Academic Press.

  9. Application of non-invasive optical monitoring methodologies to follow and record painting cleaning processes

    NASA Astrophysics Data System (ADS)

    Fontana, R.; Dal Fovo, A.; Striova, J.; Pezzati, L.; Pampaloni, E.; Raffaelli, M.; Barucci, M.

    2015-11-01

    The cleaning of painted artworks, i.e. the critical operation whereby materials are selectively removed from a painted surface by partial thinning or complete elimination of varnish, is one of the most debated conservation operations, being an irreversible process, which may result in chromatic and morphological variations in the painted surface. Due to ageing, the upper layer is subject to darkening and yellowing because of blanching and fading from ultraviolet exposure, dust deposition, and overpainted layers due, for instance, to restoration interventions. This degradation can either alter the original appearance of painting polychromy or cause mechanical failure of the finishes. To address these adverse conditions, a process of examination and analysis is critical to the definition and interpretation of the varnish layer. When investigating the ageing process of old paintings, it is of great importance to obtain insight into the painting technique as practiced in the past, and the first step in gaining this knowledge is, to a large extent, based on the study of the varnish film. An effective control of the process and objective evaluation of its outcome requires therefore instrumental/analytical support. The present study illustrates the successful application of non-invasive optical techniques—such as colorimetry, multispectral reflectography, laser scanning micro-profilometry, and optical coherence tomography—to the monitoring of an Italian fourteenth-century painting cleaning process. Results presented here confirm that optical techniques play a pivotal role in artwork diagnostics, especially with regard to conservation operations, while also indicating their validity when applied to the monitoring of the cleaning process.

  10. A Wide-Band Electromagnetic Impedance Profiling System forNon-Invasive Subsurface Characterization

    SciTech Connect

    Tseng, Hung-Wen; Lee, Ki Ha; Becker, Alex

    2004-12-17

    A non-invasive, wide-band electromagnetic (EM) impedance difference system for shallow subsurface electrical structure characterization in environmental and engineering problems has been developed at the Lawrence Berkeley National Laboratory (LBNL). Electrical parameters of interest are electrical conductivity and dielectric permittivity that are deduced from the impedance difference data. The prototype system includes a magnetic loop transmitter, which operates between 0.1 MHz and 100 MHz, an electrical dipole antenna for observing the electric field, and a loop antenna for measuring the magnetic field.All antennas are mounted on a cart made of non-metallic material for easy movement of the whole array for profiling. Surface EM impedance difference is obtained by taking the difference of the ratios of the electric fields to the magnetic fields at selected frequencies at two different levels. Numerical simulations will be presented to verify this new approach. A set of the impedance difference data acquired at the University of California's Richmond Field Station compares reasonably well with simulation results based on a model obtained with the resistivity method and in situ TDR (time domain reflectometry)measurements.

  11. Review of biomedical optical imaging—a powerful, non-invasive, non-ionizing technology for improving in vivo diagnosis

    NASA Astrophysics Data System (ADS)

    Balas, Costas

    2009-10-01

    This paper reviews the recent developments in the field of biomedical optical imaging, emphasizing technologies that have been moved from 'bench top to bedside'. Important new developments in this field allow for unprecedented visualization of the tissue microstructure and enable quantitative mapping of disease-specific endogenous and exogenous substances. With these advances, optical imaging technologies are becoming powerful clinical tools for non-invasive and objective diagnosis, guided treatment and monitoring therapies. Recent developments in visible and infrared diffuse spectroscopy and imaging, spectral imaging, optical coherence tomography, confocal imaging, molecular imaging and dynamic spectral imaging are presented together with their derivative medical devices. Their perspectives and challenges are discussed.

  12. Non-invasive Optical Measurement of Cerebral Metabolism and Hemodynamics in Infants

    PubMed Central

    Lin, Pei-Yi; Roche-Labarbe, Nadege; Dehaes, Mathieu; Carp, Stefan; Fenoglio, Angela; Barbieri, Beniamino; Hagan, Katherine; Grant, P. Ellen; Franceschini, Maria Angela

    2013-01-01

    Perinatal brain injury remains a significant cause of infant mortality and morbidity, but there is not yet an effective bedside tool that can accurately screen for brain injury, monitor injury evolution, or assess response to therapy. The energy used by neurons is derived largely from tissue oxidative metabolism, and neural hyperactivity and cell death are reflected by corresponding changes in cerebral oxygen metabolism (CMRO2). Thus, measures of CMRO2 are reflective of neuronal viability and provide critical diagnostic information, making CMRO2 an ideal target for bedside measurement of brain health. Brain-imaging techniques such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT) yield measures of cerebral glucose and oxygen metabolism, but these techniques require the administration of radionucleotides, so they are used in only the most acute cases. Continuous-wave near-infrared spectroscopy (CWNIRS) provides non-invasive and non-ionizing radiation measures of hemoglobin oxygen saturation (SO2) as a surrogate for cerebral oxygen consumption. However, SO2 is less than ideal as a surrogate for cerebral oxygen metabolism as it is influenced by both oxygen delivery and consumption. Furthermore, measurements of SO2 are not sensitive enough to detect brain injury hours after the insult 1,2, because oxygen consumption and delivery reach equilibrium after acute transients3. We investigated the possibility of using more sophisticated NIRS optical methods to quantify cerebral oxygen metabolism at the bedside in healthy and brain-injured newborns. More specifically, we combined the frequency-domain NIRS (FDNIRS) measure of SO2 with the diffuse correlation spectroscopy (DCS) measure of blood flow index (CBFi) to yield an index of CMRO2 (CMRO2i) 4,5. With the combined FDNIRS/DCS system we are able to quantify cerebral metabolism and hemodynamics. This represents an improvement over CWNIRS for detecting brain health, brain development

  13. Non-invasive optical measurement of cerebral metabolism and hemodynamics in infants.

    PubMed

    Lin, Pei-Yi; Roche-Labarbe, Nadege; Dehaes, Mathieu; Carp, Stefan; Fenoglio, Angela; Barbieri, Beniamino; Hagan, Katherine; Grant, P Ellen; Franceschini, Maria Angela

    2013-01-01

    Perinatal brain injury remains a significant cause of infant mortality and morbidity, but there is not yet an effective bedside tool that can accurately screen for brain injury, monitor injury evolution, or assess response to therapy. The energy used by neurons is derived largely from tissue oxidative metabolism, and neural hyperactivity and cell death are reflected by corresponding changes in cerebral oxygen metabolism (CMRO₂). Thus, measures of CMRO₂ are reflective of neuronal viability and provide critical diagnostic information, making CMRO₂ an ideal target for bedside measurement of brain health. Brain-imaging techniques such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT) yield measures of cerebral glucose and oxygen metabolism, but these techniques require the administration of radionucleotides, so they are used in only the most acute cases. Continuous-wave near-infrared spectroscopy (CWNIRS) provides non-invasive and non-ionizing radiation measures of hemoglobin oxygen saturation (SO₂) as a surrogate for cerebral oxygen consumption. However, SO₂ is less than ideal as a surrogate for cerebral oxygen metabolism as it is influenced by both oxygen delivery and consumption. Furthermore, measurements of SO₂ are not sensitive enough to detect brain injury hours after the insult, because oxygen consumption and delivery reach equilibrium after acute transients. We investigated the possibility of using more sophisticated NIRS optical methods to quantify cerebral oxygen metabolism at the bedside in healthy and brain-injured newborns. More specifically, we combined the frequency-domain NIRS (FDNIRS) measure of SO2 with the diffuse correlation spectroscopy (DCS) measure of blood flow index (CBFi) to yield an index of CMRO₂ (CMRO₂i). With the combined FDNIRS/DCS system we are able to quantify cerebral metabolism and hemodynamics. This represents an improvement over CWNIRS for detecting brain health, brain

  14. Non-invasive biopsy of doped-ions inside optical substrate by modified two-photon microscopy.

    PubMed

    Wang, Yao-Chin; Chen, Hsiang-Ning; Li, Wang-Yang; Chan, Ming-Che

    2015-01-26

    Doped-ion based optical elements play key roles in optical signal processes, including amplification, absorption, wavelength-filtering, lighting, and polarizing plate. Non-invasively mapping the spatial distribution of the ion concentrations in these optical elements is highly desirable either during the fabrication process or to determine their optical qualities. In this work, we applied modified two-photon fluorescence (m-TPF) microscopy to trace the ion-distributions deep inside the optical elements. For demonstration purposes, polyvinyl alcohol (PVA) polymer films inside polarizing plates are taken as an example, where the spatial distributions of Iodine-dyed ions were measured by the m-TPF microscope in a fast and non-invasive way. The durability of the polarizer films can be distinguished from the axial distribution of the Iodine-dyed ions, without the need to perform a biopsy. This proposed method and demonstrated results show great potential for monitoring the spatial distributions of doped-ions in the optical elements quickly and non-destructively, which would be of great benefit in both scientific research and industrial applications. PMID:25835941

  15. A non-invasive miniaturized-wireless laser-Doppler fiber optic sensor for understanding distal fingertip injuries in astronauts

    NASA Astrophysics Data System (ADS)

    Ansari, Rafat R.; Jones, Jeffrey A.; Pollonini, Luca; Rodriguez, Mikael; Opperman, Roedolph; Hochstein, Jason

    2009-02-01

    During extra-vehicular activities (EVAs) or space walks astronauts over use their fingertips under pressure inside the confined spaces of gloves/space-suite. The repetitive hand motion is a probable cause for discomfort and injuries to the finger-tips. We describe a new wireless fiber-optic probe that can be integrated inside the astronaut glove for non-invasive blood perfusion measurements in distal finger tips. In this preliminary study, we present blood perfusion measurements while performing hand-grip exercises simulating the use of space tools.

  16. Joint application of non-invasive techniques to characterize the dynamic behaviuor of engineering structures

    NASA Astrophysics Data System (ADS)

    Gallipoli, M. R.; Perrone, A.; Stabile, T. A.; Ponzo, F. C.; Ditommaso, R.

    2012-04-01

    The systematic monitoring of strategic civil infrastructures such as bridges, large dams or high-rise buildings in order to ensure their structural stability is a strategic issue particularly in earthquake-prone regions. Nevertheless, in areas less exposed to seismic hazard, the monitoring is also an important tool for civil engineers, for instance if they have to deal with structures exposed to heavy operational demands for extended periods of time and whose structural integrity might be in question or at risk. A continuous monitoring of such structures allows the identification of their fundamental response characteristics and the changes of these over time, the latter representing indicators for potential structural degradation. The aim of this paper is the estimation of fundamental dynamic parameters of some civil infrastructures by the joint application of fast executable, non-invasive techniques such as the Ambient Noise Standard Spectral Ratio, and Ground-Based microwave Radar Interferometer techniques. The joint approach combine conventional, non-conventional and innovative techniques in order to set up a non destructive evaluation procedure allowing for a multi-sensing monitoring at a multi-scale and multi-depth levels (i.e. with different degrees of spatial resolution and different subsurface depths). In particular, techniques based on ambient vibration recordings have become a popular tool for characterizing the seismic response and state-of-health of strategic civil infrastructure. The primary advantage of these approaches lies in the fact that no transient earthquake signals or even active excitation of the structure under investigation are required. The microwave interferometry radar technology, it has proven to be a powerful remote sensing tool for vibration measurement of structures, such as bridge, heritage architectural structures, vibrating stay cables, and engineering structures. The main advantage of this radar technique is the possibility to

  17. Investigation of opportunities of the optical non-invasive diagnostics method for the blood sugar control

    NASA Astrophysics Data System (ADS)

    Lastovskaia, Elena A.; Gorbunova, Elena V.; Chertov, Aleksandr N.; Korotaev, Valery V.

    2015-03-01

    The relevance of noninvasive method for determining the blood sugar is caused by necessity of regular monitoring of glucose levels in diabetic patients blood. Traditional invasive method is painful, because it requires a finger pricking. Despite the active studies in the field of non-invasive medical diagnostics, to date the painless and inexpensive instrument for blood sugar control for personal use doesn't exist. It's possible to measure the concentration of glucose in the blood with help of spectrophotometry method. It consists of registering and analyzing the spectral characteristics of the radiation which missed, reflected or absorbed by the object. The authors proposed a measuring scheme for studying the spectral characteristics of the radiation, missed by earlobe. Ultra-violet, visible and near infrared spectral ranges are considered. The paper presents the description of construction and working principles of the proposed special retaining clip and results of experiment with real patient.

  18. Non-invasive assessment of hemispheric language dominance by optical topography during a brief passive listening test: A pilot study

    PubMed Central

    Bembich, Stefano; Demarini, Sergio; Clarici, Andrea; Massaccesi, Stefano; Grasso, Domenico Leonardo

    2011-01-01

    Summary Background The Wada test is usually used for pre-surgical assessment of language lateralization. Considering its invasiveness and risk of complications, alternative methods have been proposed but they are not always applicable to non-cooperative patients. In this study we explored the possibility of using optical topography (OT) – a multichannel near-infrared system – for non-invasive assessment of hemispheric language dominance during passive listening. Material/Methods Cortical activity was monitored in a sample of healthy, adult Italian native speakers, all right-handed. We assessed changes in oxy-haemoglobin concentration in temporal, parietal and posterior frontal lobes during a passive listening of bi-syllabic words and vowel-consonant-vowel syllables lasting less then 3 minutes. Activated channels were identified by t tests. Results Left hemisphere showed significant activity only during the passive listening of bi-syllabic words. Specifically, the superior temporal gyrus, the supramarginal gyrus and the posterior inferior parietal lobe were activated. Conclusions During passive listening of bi-syllabic words, right handed healthy adults showed a significant activation in areas already known to be involved in speech comprehension. Although more research is needed, OT proved to be a promising alternative to the Wada test for non-invasive assessment of hemispheric language lateralization, even if using a particularly brief trial, which has been designed for future applications with non-cooperative subjects. PMID:22129900

  19. Adaptive optics optical coherence tomography at 120,000 depth scans/s for non-invasive cellular phenotyping of the living human retina

    PubMed Central

    Torti, Cristiano; Považay, Boris; Hofer, Bernd; Unterhuber, Angelika; Carroll, Joseph; Ahnelt, Peter Kurt; Drexler, Wolfgang

    2012-01-01

    This paper presents a successful combination of ultra-high speed (120,000 depth scans/s), ultra-high resolution optical coherence tomography with adaptive optics and an achromatizing lens for compensation of monochromatic and longitudinal chromatic ocular aberrations, respectively, allowing for non-invasive volumetric imaging in normal and pathologic human retinas at cellular resolution. The capability of this imaging system is demonstrated here through preliminary studies by probing cellular intraretinal structures that have not been accessible so far with in vivo, non-invasive, label-free imaging techniques, including pigment epithelial cells, micro-vasculature of the choriocapillaris, single nerve fibre bundles and collagenous plates of the lamina cribrosa in the optic nerve head. In addition, the volumetric extent of cone loss in two colour-blinds could be quantified for the first time. This novel technique provides opportunities to enhance the understanding of retinal pathogenesis and early diagnosis of retinal diseases. PMID:19997159

  20. A Non-invasive Platform for Functional Characterization of Stem-Cell-Derived Cardiomyocytes with Applications in Cardiotoxicity Testing

    PubMed Central

    Maddah, Mahnaz; Heidmann, Julia D.; Mandegar, Mohammad A.; Walker, Chase D.; Bolouki, Sara; Conklin, Bruce R.; Loewke, Kevin E.

    2015-01-01

    Summary We present a non-invasive method to characterize the function of pluripotent stem-cell-derived cardiomyocytes based on video microscopy and image analysis. The platform, called Pulse, generates automated measurements of beating frequency, beat duration, amplitude, and beat-to-beat variation based on motion analysis of phase-contrast images captured at a fast frame rate. Using Pulse, we demonstrate recapitulation of drug effects in stem-cell-derived cardiomyocytes without the use of exogenous labels and show that our platform can be used for high-throughput cardiotoxicity drug screening and studying physiologically relevant phenotypes. PMID:25801505

  1. Non-invasive characterization and quality assurance of silicon micro-strip detectors using pulsed infrared laser

    NASA Astrophysics Data System (ADS)

    Ghosh, P.

    2016-01-01

    The Compressed Baryonic Matter (CBM) experiment at FAIR is composed of 8 tracking stations consisting of roughly 1300 double sided silicon micro-strip detectors of 3 different dimensions. For the quality assurance of prototype micro-strip detectors a non-invasive detector charaterization is developed. The test system is using a pulsed infrared laser for charge injection and characterization, called Laser Test System (LTS). The system is aimed to develop a set of characterization procedures which are non-invasive (non-destructive) in nature and could be used for quality assurances of several silicon micro-strip detectors in an efficient, reliable and reproducible way. The procedures developed (as reported here) uses the LTS to scan sensors with a pulsed infra-red laser driven by step motor to determine the charge sharing in-between strips and to measure qualitative uniformity of the sensor response over the whole active area. The prototype detector modules which are tested with the LTS so far have 1024 strips with a pitch of 58 μm on each side. They are read-out using a self-triggering prototype read-out electronic ASIC called n-XYTER. The LTS is designed to measure sensor response in an automatized procedure at several thousand positions across the sensor with focused infra-red laser light (spot size ≈ 12 μm, wavelength = 1060 nm). The pulse with a duration of ≈ 10 ns and power ≈ 5 mW of the laser pulse is selected such, that the absorption of the laser light in the 300 μm thick silicon sensor produces ≈ 24000 electrons, which is similar to the charge created by minimum ionizing particles (MIP) in these sensors. The laser scans different prototype sensors and various non-invasive techniques to determine characteristics of the detector modules for the quality assurance is reported.

  2. Improved non-invasive Optical Coherence Tomography detection of different engineered nanoparticles in food-mimicking matrices.

    PubMed

    Grombe, Ringo; Kirsten, Lars; Mehner, Mirko; Linsinger, Thomas P J; Koch, Edmund

    2016-12-01

    Food industry and regulators require fast and reliable analytical methods for quality control. This especially counts for the detection of engineered nanomaterials (ENMs) in food products. Respective EU regulation is in force, but the development of appropriate methods is still underway. This paper updates the scope of Optical Coherence Tomography (OCT) for ENM/food matrix analysis. A range of nanomaterials and composites - Au@SiO2, Ag, Ag@SiO2 and SiO2 - in a simplified food matrix was investigated. The earlier finding of linear dependencies between concentration in the dispersion and light responses could be reproduced. Being able to analyse non-invasively for a relevant industrial compound such as SiO2, makes OCT an excellent candidate for screening purposes. PMID:27374569

  3. Effect of Injector Geometry on Atomization of a Liquid-Liquid Double Swirl Coaxial Injector Using Non-invasive Laser, Optical and X-ray Techniques

    NASA Technical Reports Server (NTRS)

    Radke, C. R.; Meyer, T. R.

    2014-01-01

    The spray characteristics of a liquid-liquid double swirl coaxial injector were studied using non-invasive optical, laser, and X-ray diagnostics. A parametric study of injector exit geometry demonstrated that spray breakup time, breakup type and sheet stability could be controlled with exit geometry. Phase Doppler interferometry was used to characterize droplet statistics and non-dimensional droplet parameters over a range of inlet conditions and for various fluids allowing for a study on the role of specific fluid properties in atomization. Further, X-ray radiography allowed for investigation of sheet thickness and breakup length to be quantified for different recess exit diameters and inlet pressures. Finally, computed tomography scans revealed that the spray cone was distinctively non-uniform and comprised of several pockets of increased mass flux.

  4. Characterization and profiling of immunomodulatory genes of equine mesenchymal stromal cells from non-invasive sources

    PubMed Central

    2014-01-01

    Introduction Mesenchymal stromal cells (MSCs) have been extensively studied for their promising capabilities in regenerative medicine. Although bone marrow is the best-known source for isolating equine MSCs, non-invasive alternative sources such as umbilical cord blood (UCB), umbilical cord matrix (UCM), and peripheral blood (PB) have also been reported. Methods Equine MSCs from three non-invasive alternative sources were isolated from six individual mares (PB) and their foals (UCB and UCM) at parturition. To minimize inter-horse variability, the samples from the three sources were matched within the same mare and for UCB and UCM even within the same foal from that specific mare. The following parameters were analyzed: (i) success rate of isolation, (ii) proliferation capacity, (iii) tri-lineage differentiation ability, (iv) immunophenotypical protein, and (v) immunomodulatory mRNA profiles. Linear regression models were fit to determine the association between the source of MSCs (UCB, UCM, PB) and (i) the moment of first observation, (ii) the moment of first passage, (iii) cell proliferation data, (iv) the expression of markers related to cell immunogenicity, and (v) the mRNA profile of immunomodulatory factors, except for hepatocyte growth factor (HGF) as no normal distribution could be obtained for the latter variable. To evaluate the association between the source of MSCs and the mRNA expression of HGF, the non-parametric Kruskal-Wallis test was performed instead. Results While equine MSCs could be isolated from all the UCB and PB samples, isolation from UCM was successful in only two samples because of contamination issues. Proliferation data showed that equine MSCs from all three sources could be easily expanded, although UCB-derived MSCs appeared significantly faster in culture than PB- or UCM-derived MSCs. Equine MSCs from both UCB and PB could be differentiated toward the osteo-, chondro-, and adipogenic lineage, in contrast to UCM-derived MSCs in which

  5. Non-invasive characterization of motor unit behaviour in pathological tremor

    NASA Astrophysics Data System (ADS)

    Holobar, A.; Glaser, V.; Gallego, J. A.; Dideriksen, J. L.; Farina, D.

    2012-10-01

    This paper presents the fully automatic identification of motor unit spike trains from high-density surface electromyograms (EMG) in pathological tremor. First, a mathematical derivation is provided to theoretically prove the possibility of decomposing noise-free high-density surface EMG signals into motor unit spike trains with high correlation, which are typical of tremor contractions. Further, the proposed decomposition method is tested on simulated signals with different levels of noise and on experimental signals from 14 tremor-affected patients. In the case of simulated tremor with central frequency ranging from 5 Hz to 11 Hz and signal-to-noise ratio of 20 dB, the method identified ˜8 motor units per contraction with sensitivity in spike timing identification ≥95% and false alarm and miss rates ≤5%. In experimental signals, the number of identified motor units varied substantially (range 0-21) across patients and contraction types, as expected. The behaviour of the identified motor units was consistent with previous data obtained by intramuscular EMG decomposition. These results demonstrate for the first time the possibility of a fully non-invasive investigation of motor unit behaviour in tremor-affected patients. The method provides a new means for physiological investigations of pathological tremor.

  6. Non-invasive imaging and monitoring of rodent retina using simultaneous dual-band optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Cimalla, Peter; Burkhardt, Anke; Walther, Julia; Hoefer, Aline; Wittig, Dierk; Funk, Richard; Koch, Edmund

    2011-03-01

    Spectral domain dual-band optical coherence tomography for simultaneous imaging of rodent retina in the 0.8 μm and 1.3 μm wavelength region and non-invasive monitoring of the posterior eye microstructure in the field of retinal degeneration research is demonstrated. The system is illuminated by a supercontinuum laser source and allows three-dimensional imaging with high axial resolution better than 3.8 μm and 5.3 μm in tissue at 800 nm and 1250 nm, respectively, for precise retinal thickness measurements. A fan-shaped scanning pattern with the pivot point close to the eye's pupil and a contact lens are applied to obtain optical access to the eye's fundus. First in vivo experiments in a RCS (royal college of surgeons) rat model with gene-related degeneration of the photoreceptor cells show good visibility of the retinal microstructure with sufficient contrast for thickness measurement of individual retinal layers. An enhanced penetration depth at 1250 nm is clearly identifiable revealing sub-choroidal structures that are not visible at 800 nm. Furthermore, additional simultaneous imaging at 1250 nm improves image quality by frequency compounding speckle noise reduction. These results are encouraging for time course studies of the rodent retina concerning its development related to disease progression and treatment response.

  7. Non-Invasive Optical Sensor Based Approaches for Monitoring Virus Culture to Minimize BSL3 Laboratory Entry.

    PubMed

    Ragupathy, Viswanath; Setty, Mohan Kumar Hayuri Giri; Kostov, Yordan; Ge, Xudong; Uplekar, Shaunak; Hewlett, Indira; Rao, Govind

    2015-01-01

    High titers of infectious viruses for vaccine and diagnostic reference panel development are made by infecting susceptible mammalian cells. Laboratory procedures are strictly performed in a Bio-Safety Level-3 (BSL3) laboratory and each entry and exit involves the use of  disposable Personnel Protective Equipment (PPE) to observe cell culture conditions. Routine PPE use involves significant recurring costs. Alternative non-invasive optical sensor based approaches to remotely monitor cell culture may provide a promising and cost effective approach to monitor infectious virus cultures resulting in lower disruption and costs. We report here the monitoring of high titer cultures of Human Immunodeficiency Virus-1 (HIV-1) and Herpes Simplex Virus-2 (HSV-2) remotely with the use of optical oxygen sensors aseptically placed inside the cell culture vessel. The replacement of culture media for cell and virus propagation and virus load monitoring was effectively performed using this fluorescent sensor and resulted in half the number of visits to the BSL3 lab (five versus ten). PMID:26115456

  8. A review of non-invasive optical-based image analysis systems for continuous bioprocess monitoring.

    PubMed

    Höpfner, Tim; Bluma, Arne; Rudolph, Guido; Lindner, Patrick; Scheper, Thomas

    2010-02-01

    To observe and control cultivation processes, optical sensors are used increasingly. Important variables for controlling such processes are cell count, cell size distribution and the morphology of cells. Among turbidity measurement methods, imaging procedures are applied for determining these process values. A disadvantage of most previously developed imaging procedures is that they are only available offline, which requires sampling. On the other hand, available imaging inline probes can only deliver a limited number of process values so far. This contribution gives an overview of optical procedures for the inline determination of cell count, cell size distribution and other variables. In particular, by in situ microscopy, an imaging procedure will be described, which allows the determination of direct and non-direct cell variables in real time without sampling. PMID:19396466

  9. Ultrasonic non invasive techniques for microbiological instrumentation

    NASA Astrophysics Data System (ADS)

    Elvira, L.; Sierra, C.; Galán, B.; Resa, P.

    2010-01-01

    Non invasive techniques based on ultrasounds have advantageous features to study, characterize and monitor microbiological and enzymatic reactions. These processes may change the sound speed, viscosity or particle distribution size of the medium where they take place, which makes possible their analysis using ultrasonic techniques. In this work, two different systems for the analysis of microbiological liquid media based on ultrasounds are presented. In first place, an industrial application based on an ultrasonic monitoring technique for microbiological growth detection in milk is shown. Such a system may improve the quality control strategies in food production factories, being able to decrease the time required to detect possible contaminations in packed products. Secondly, a study about the growing of the Escherichia coli DH5 α in different conditions is presented. It is shown that the use of ultrasonic non invasive characterization techniques in combination with other conventional measurements like optical density provides complementary information about the metabolism of these bacteria.

  10. Non-invasive optical imaging of tumor growth in intact animals

    NASA Astrophysics Data System (ADS)

    Lu, Jinling; Li, Pengcheng; Luo, Qingming; Zhu, Dan

    2003-12-01

    We describe here a system for rapidly visualizing tumor growth in intact rodent mice that is simple, rapid, and eminently accessible and repeatable. We have established new rodent tumor cell line -- SP2/0-GFP cells that stably express high level of green fluorescent protein (GFP) by transfected with a plasmid that encoded GFP using electroporation and selected with G418 for 3 weeks. 1 x 104 - 1x107 SP2/0-GFP mouse melanoma cells were injected s.c. in the ears and legs of 6- to 7-week-old syngeneic male BALB/c mice, and optical images visualized real-time the engrafted tumor growth. The tumor burden was monitored over time by cryogenically cooled charge coupled device (CCD) camera focused through a stereo microscope. The results show that the fluorescence intensity of GFP-expressing tumor is comparably with the tumor growth and/or depress. This in vivo optical imaging based on GFP is sensitive, external, and noninvasive. It affords continuous visual monitoring of malignant growth within intact animals, and may comprise an ideal tool for evaluating antineoplastic therapies.

  11. Towards non-invasive 3D hepatotoxicity assays with optical coherence phase microscopy

    NASA Astrophysics Data System (ADS)

    Nelson, Leonard J.; Koulovasilopoulos, Andreas; Treskes, Philipp; Hayes, Peter C.; Plevris, John N.; Bagnaninchi, Pierre O.

    2015-03-01

    Three-dimensional tissue-engineered models are increasingly recognised as more physiologically-relevant than standard 2D cell culture for pre-clinical drug toxicity testing. However, many types of conventional toxicity assays are incompatible with dense 3D tissues. This study investigated the use of optical coherence phase microscopy (OCPM) as a novel approach to assess cell death in 3D tissue culture. For 3D micro-spheroid formation Human hepatic C3A cells were encapsulated in hyaluronic acid gels and cultured in 100μl MEME/10%FBS in 96-well plates. After spheroid formation the 3D liver constructs were exposed to acetaminophen on culture day 8. Acetaminophen hepatotoxicity in 3D cultures was evaluated using standard biochemical assays. An inverted OCPM in common path configuration was developed with a Callisto OCT engine (Thorlabs), centred at 930nm and a custom scanning head. Intensity data were used to perform in-depth microstructural imaging. In addition, phase fluctuations were measured by collecting several successive B scans at the same location, and statistics on the first time derivative of the phase, i.e. time fluctuations, were analysed over the acquisition time interval to retrieve overall cell viability. OCPM intensity (cell cluster size) and phase fluctuation statistics were directly compared with biochemical assays. In this study, we investigated optical coherence phase tomography to assess cell death in a 3d liver model after exposure to a prototypical hepatotoxin, acetaminophen. We showed that OCPM has the potential to assess noninvasively and label-free drug toxicity in 3D tissue models.

  12. A novel non-invasive optical method for quantitative visualization of pH dynamics in the rhizosphere of plants.

    PubMed

    Blossfeld, Stephan; Gansert, Dirk

    2007-02-01

    A novel optical method for non-invasive, quantitative and high-resolution imaging of spatial and temporal pH dynamics in soils mediated by plant roots is introduced. This method overcomes present limitations of measurement of pH, mainly short-term and punctiform measurements, by recording long-term dynamics of the micro-pattern of pH in the root-soil interface without disturbance of the biological and physico-chemical conditions. Juncus effusus L., rooting in a permanently flooded rhizotron, was selected as the test organism for qualifying the technique. The measurements showed pronounced diurnal variations of pH along the roots, particularly along the elongation zone. Diurnal oscillation of pH caused by the roots reached up to 0.5 units. Long-term records at 4 s intervals over more than 8 weeks revealed considerable spatial and temporal patterns of pH dynamics in the rhizosphere of about 10% of the pH scale (pH 7.0-8.5). The measured data were validated by the use of pH electrodes. Concomitantly measured oxygen concentration showed hypoxic conditions around root tips (10-70 micromol O2 L-1) and almost anoxic conditions (0.9 micromol O2 L-1) in the bulk soil. The present study qualifies this novel pH-sensing technique as a powerful analytical tool for quantitative visualization of undisturbed bioprocess dynamics. PMID:17238909

  13. Note: Non-invasive optical method for rapid determination of alignment degree of oriented nanofibrous layers

    NASA Astrophysics Data System (ADS)

    Pokorny, M.; Klemes, J.; Rebicek, J.; Kotzianova, A.; Velebny, V.

    2015-10-01

    This paper presents a rapid non-destructive method that provides information on the anisotropic internal structure of nanofibrous layers. A laser beam of a wavelength of 632.8 nm is directed at and passes through a nanofibrous layer prepared by electrostatic spinning. Information about the structural arrangement of nanofibers in the layer is directly visible in the form of a diffraction image formed on a projection screen or obtained from measured intensities of the laser beam passing through the sample which are determined by the dependency of the angle of the main direction of polarization of the laser beam on the axis of alignment of nanofibers in the sample. Both optical methods were verified on Polyvinyl alcohol (PVA) nanofibrous layers (fiber diameter of 470 nm) with random, single-axis aligned and crossed structures. The obtained results match the results of commonly used methods which apply the analysis of electron microscope images. The presented simple method not only allows samples to be analysed much more rapidly and without damaging them but it also makes possible the analysis of much larger areas, up to several square millimetres, at the same time.

  14. Note: Non-invasive optical method for rapid determination of alignment degree of oriented nanofibrous layers

    SciTech Connect

    Pokorny, M.; Rebicek, J.; Klemes, J.; Kotzianova, A.; Velebny, V.

    2015-10-15

    This paper presents a rapid non-destructive method that provides information on the anisotropic internal structure of nanofibrous layers. A laser beam of a wavelength of 632.8 nm is directed at and passes through a nanofibrous layer prepared by electrostatic spinning. Information about the structural arrangement of nanofibers in the layer is directly visible in the form of a diffraction image formed on a projection screen or obtained from measured intensities of the laser beam passing through the sample which are determined by the dependency of the angle of the main direction of polarization of the laser beam on the axis of alignment of nanofibers in the sample. Both optical methods were verified on Polyvinyl alcohol (PVA) nanofibrous layers (fiber diameter of 470 nm) with random, single-axis aligned and crossed structures. The obtained results match the results of commonly used methods which apply the analysis of electron microscope images. The presented simple method not only allows samples to be analysed much more rapidly and without damaging them but it also makes possible the analysis of much larger areas, up to several square millimetres, at the same time.

  15. Note: Non-invasive optical method for rapid determination of alignment degree of oriented nanofibrous layers.

    PubMed

    Pokorny, M; Klemes, J; Rebicek, J; Kotzianova, A; Velebny, V

    2015-10-01

    This paper presents a rapid non-destructive method that provides information on the anisotropic internal structure of nanofibrous layers. A laser beam of a wavelength of 632.8 nm is directed at and passes through a nanofibrous layer prepared by electrostatic spinning. Information about the structural arrangement of nanofibers in the layer is directly visible in the form of a diffraction image formed on a projection screen or obtained from measured intensities of the laser beam passing through the sample which are determined by the dependency of the angle of the main direction of polarization of the laser beam on the axis of alignment of nanofibers in the sample. Both optical methods were verified on Polyvinyl alcohol (PVA) nanofibrous layers (fiber diameter of 470 nm) with random, single-axis aligned and crossed structures. The obtained results match the results of commonly used methods which apply the analysis of electron microscope images. The presented simple method not only allows samples to be analysed much more rapidly and without damaging them but it also makes possible the analysis of much larger areas, up to several square millimetres, at the same time. PMID:26521008

  16. In vivo photothermal optical coherence tomography for non-invasive imaging of endogenous absorption agents

    PubMed Central

    Makita, Shuichi; Yasuno, Yoshiaki

    2015-01-01

    In vivo photothermal optical coherence tomography (OCT) is demonstrated for cross-sectional imaging of endogenous absorption agents. In order to compromise the sensitivity, imaging speed, and sample motion immunity, a new photothermal detection scheme and phase processing method are developed. Phase-resolved swept-source OCT and fiber-pigtailed laser diode (providing excitation at 406 nm) are combined to construct a high-sensitivity photothermal OCT system. OCT probe and excitation beam coaxially illuminate and are focused on tissues. The photothermal excitation and detection procedure is designed to obtain high efficiency of photothermal effect measurement. The principle and method of depth-resolved cross-sectional imaging of absorption agents with photothermal OCT has been derived. The phase-resolved thermal expansion detection algorithm without motion artifact enables in vivo detection of photothermal effect. Phantom imaging with a blood phantom and in vivo human skin imaging are conducted. A phantom with guinea-pig blood as absorber has been scanned by the photothermal OCT system to prove the concept of cross-sectional absorption agent imaging. An in vivo human skin measurement is also performed with endogenous absorption agents. PMID:26137374

  17. Non-invasive timing of gas gun-launched projectiles using external surface-mounted optical fiber-Bragg grating strain gauges

    NASA Astrophysics Data System (ADS)

    Goodwin, Peter M.; Marshall, Bruce R.; Stevens, Gerald D.; Dattelbaum, Dana M.

    2013-03-01

    Non-invasive detection methods for tracking gun-launched projectiles are important not only for assessment of gun performance but are also essential for timing a variety of diagnostics, for example, to investigate plate-impact events for shock compression experiments. Measurement of the time of passage of a projectile moving inside of the gun barrel can be achieved by detection of the transient hoop strain induced in the barrel of a light-gas gun by the passage of the projectile using external, barrel surface-mounted optical fiber-Bragg grating strain gauges. Optical fiber-Bragg gratings have been implemented and their response characterized on single-stage and two-stage light gas guns routinely used for dynamic experimentation at Los Alamos National Laboratory. Two approaches, using either broadband or narrowband illumination, were used to monitor changes in the Bragg wavelength of the fiber-Bragg gratings. The second approach, using narrowband laser illumination, offered the highest sensitivity. The feasibility of using these techniques to generate early, pre-event signals useful for triggering high-latency diagnostics was demonstrated.

  18. Non-invasive timing of gas gun-launched projectiles using external surface-mounted optical fiber-Bragg grating strain gauges.

    PubMed

    Goodwin, Peter M; Marshall, Bruce R; Stevens, Gerald D; Dattelbaum, Dana M

    2013-03-01

    Non-invasive detection methods for tracking gun-launched projectiles are important not only for assessment of gun performance but are also essential for timing a variety of diagnostics, for example, to investigate plate-impact events for shock compression experiments. Measurement of the time of passage of a projectile moving inside of the gun barrel can be achieved by detection of the transient hoop strain induced in the barrel of a light-gas gun by the passage of the projectile using external, barrel surface-mounted optical fiber-Bragg grating strain gauges. Optical fiber-Bragg gratings have been implemented and their response characterized on single-stage and two-stage light gas guns routinely used for dynamic experimentation at Los Alamos National Laboratory. Two approaches, using either broadband or narrowband illumination, were used to monitor changes in the Bragg wavelength of the fiber-Bragg gratings. The second approach, using narrowband laser illumination, offered the highest sensitivity. The feasibility of using these techniques to generate early, pre-event signals useful for triggering high-latency diagnostics was demonstrated. PMID:23556841

  19. 3-D SPECTRAL IP IMAGING: NON-INVASIVE CHARACTERIZATION OF CONTAMINANT PLUMES

    EPA Science Inventory

    The objective of this study is to develop a noninvasive tomographic imaging technique,based on the spectral induced-polarization method, to characterize the in-situ distribution of organic and inorganic groundwater contaminants. Recent advances in tomographic imaging, applied to ...

  20. Assessment of disease activity in patients with rheumatoid arthritis using optical spectral transmission measurements, a non-invasive imaging technique

    PubMed Central

    van Onna, M; Ten Cate, D F; Tsoi, K L; Meier, A J L; Jacobs, J W G; Westgeest, A A A; Meijer, P B L; van Beek, M C; Rensen, W H J; Bijlsma, J W J

    2016-01-01

    Objectives In rheumatoid arthritis (RA), treat-to-target strategies require instruments for valid detection of joint inflammation. Therefore, imaging modalities are increasingly used in clinical practice. Optical spectral transmission (OST) measurements are non-invasive and fast and may therefore have benefits over existing imaging modalities. We tested whether OST could measure disease activity validly in patients with RA. Methods In 59 patients with RA and 10 patients with arthralgia, OST, joint counts, Disease Activity Score (DAS) 28 and ultrasonography (US) were performed. Additionally, MRI was performed in patients with DAS28<2.6. We developed and validated within the same cohort an algorithm for detection of joint inflammation by OST with US as reference. Results At the joint level, OST and US performed similarly inproximal interphalangeal-joints (area under the receiver-operating curve (AUC) of 0.79, p<0.0001) andmetacarpophalangeal joints (AUC 0.78, p<0.0001). Performance was less similar in wrists (AUC 0.62, p=0.006). On the patient level, OST correlated moderately with clinical examination (DAS28 r=0.42, p=0.001), and US scores (r=0.64, p<0.0001). Furthermore, in patients with subclinical and low disease activity, there was a correlation between OST and MRI synovitis score (RAMRIS (Rheumatoid Arthritis MRI Scoring) synovitis), r=0.52, p=0.005. Conclusions In this pilot study, OST performed moderately in the detection of joint inflammation in patients with RA. Further studies are needed to determine the diagnostic performance in a new cohort of patients with RA. PMID:26452538

  1. Characterization of Solid Liquid Suspensions Utilizing Non-Invasive Ultrasonic Measurements

    SciTech Connect

    Panetta, P.D.; Tucker, B.; Ahmed, S.; Pappas, R.A.

    2004-03-31

    Rapid, on-line characterization of the particle size and concentration of moderate to highly concentrated slurries is required for efficient waste remediation at the DOE complexes. This paper discusses the advancements achieved under the Environmental Management Science Program to accurately characterize high-level waste at the high concentrations expected at the DOE complexes. In addition, the results are applicable to efficient process measurement and control in many chemical and pharmaceutical manufacturing processes. Existing methods for determining the particle size and concentration of non-dilute slurries based on ultrasonic attenuation can become inaccurate due to the complex interactions of ultrasonic waves with the constituents of the slurries and the necessity for very careful transducer alignment. Two measurements that help to overcome these difficulties are the ultrasonic backscattering and diffuse field. The backscattering measurement is attractive because viscous, thermal and inertial effects have small contributions to the backscattering. In addition, the backscattering theories are simpler than attenuation theories and lend themselves to more stable inversion processes. Furthermore, the measurements of backscattering measurement do not require long travel distances and can be made with a single transducer thus eliminating alignment problems. We will present ultrasonic measurements and theoretical comparisons on solid liquid suspensions designed to elucidate the particle size and concentration at high concentration relevant to the high level waste at the DOE complexes.

  2. Targeting Paraprotein Biosynthesis for Non-Invasive Characterization of Myeloma Biology

    PubMed Central

    Spahmann, Annika; Jörg, Gerhard; Samnick, Samuel; Rosenwald, Andreas; Einsele, Herrmann; Knop, Stefan; Buck, Andreas K.

    2013-01-01

    Purpose Multiple myeloma is a hematologic malignancy originating from clonal plasma cells. Despite effective therapies, outcomes are highly variable suggesting marked disease heterogeneity. The role of functional imaging for therapeutic management of myeloma, such as positron emission tomography with 2-deoxy-2-[18F]fluoro-D-glucose (18F-FDG-PET), remains to be determined. Although some studies already suggested a prognostic value of 18F-FDG-PET, more specific tracers addressing hallmarks of myeloma biology, e.g. paraprotein biosynthesis, are needed. This study evaluated the amino acid tracers L-methyl-[11C]-methionine (11C-MET) and [18F]-fluoroethyl-L-tyrosine (18F-Fet) for their potential to image myeloma and to characterize tumor heterogeneity. Experimental Design To study the utility of 11C-MET, 18F-Fet and 18F-FDG for myeloma imaging, time activity curves were compared in various human myeloma cell lines (INA-6, MM1.S, OPM-2) and correlated to cell-biological characteristics, such as marker gene expression and immunoglobulin levels. Likewise, patient-derived CD138+ plasma cells were characterized regarding uptake and biomedical features. Results Using myeloma cell lines and patient-derived CD138+ plasma cells, we found that the relative uptake of 11C-MET exceeds that of 18F-FDG 1.5- to 5-fold and that of 18F-Fet 7- to 20-fold. Importantly, 11C-MET uptake significantly differed between cell types associated with worse prognosis (e.g. t(4;14) in OPM-2 cells) and indolent ones and correlated with intracellular immunoglobulin light chain and cell surface CD138 and CXCR4 levels. Direct comparison of radiotracer uptake in primary samples further validated the superiority of 11C-MET. Conclusion These data suggest that 11C-MET might be a versatile biomarker for myeloma superior to routine functional imaging with 18F-FDG regarding diagnosis, risk stratification, prognosis and discrimination of tumor subtypes. PMID:24376850

  3. Non-invasive flow path characterization in a mining-impacted wetland

    NASA Astrophysics Data System (ADS)

    Bethune, James; Randell, Jackie; Runkel, Robert L.; Singha, Kamini

    2015-12-01

    Time-lapse electrical resistivity (ER) was used to capture the dilution of a seasonal pulse of acid mine drainage (AMD) contamination in the subsurface of a wetland downgradient of the abandoned Pennsylvania mine workings in central Colorado. Data were collected monthly from mid-July to late October of 2013, with an additional dataset collected in June of 2014. Inversion of the ER data shows the development through time of multiple resistive anomalies in the subsurface, which corroborating data suggest are driven by changes in total dissolved solids (TDS) localized in preferential flow pathways. Sensitivity analyses on a synthetic model of the site suggest that the anomalies would need to be at least several meters in diameter to be adequately resolved by the inversions. The existence of preferential flow paths would have a critical impact on the extent of attenuation mechanisms at the site, and their further characterization could be used to parameterize reactive transport models in developing quantitative predictions of remediation strategies.

  4. Non-invasive flow path characterization in a mining-impacted wetland.

    PubMed

    Bethune, James; Randell, Jackie; Runkel, Robert L; Singha, Kamini

    2015-12-01

    Time-lapse electrical resistivity (ER) was used to capture the dilution of a seasonal pulse of acid mine drainage (AMD) contamination in the subsurface of a wetland downgradient of the abandoned Pennsylvania mine workings in central Colorado. Data were collected monthly from mid-July to late October of 2013, with an additional dataset collected in June of 2014. Inversion of the ER data shows the development through time of multiple resistive anomalies in the subsurface, which corroborating data suggest are driven by changes in total dissolved solids (TDS) localized in preferential flow pathways. Sensitivity analyses on a synthetic model of the site suggest that the anomalies would need to be at least several meters in diameter to be adequately resolved by the inversions. The existence of preferential flow paths would have a critical impact on the extent of attenuation mechanisms at the site, and their further characterization could be used to parameterize reactive transport models in developing quantitative predictions of remediation strategies. PMID:26529300

  5. Non-invasive flow path characterization in a mining-impacted wetland

    USGS Publications Warehouse

    Bethune, James; Randell, Jackie; Runkel, Robert L.; Singha, Kamini

    2015-01-01

    Time-lapse electrical resistivity (ER) was used to capture the dilution of a seasonal pulse of acid mine drainage (AMD) contamination in the subsurface of a wetland downgradient of the abandoned Pennsylvania mine workings in central Colorado. Data were collected monthly from mid-July to late October of 2013, with an additional dataset collected in June of 2014. Inversion of the ER data shows the development through time of multiple resistive anomalies in the subsurface, which corroborating data suggest are driven by changes in total dissolved solids (TDS) localized in preferential flow pathways. Sensitivity analyses on a synthetic model of the site suggest that the anomalies would need to be at least several meters in diameter to be adequately resolved by the inversions. The existence of preferential flow paths would have a critical impact on the extent of attenuation mechanisms at the site, and their further characterization could be used to parameterize reactive transport models in developing quantitative predictions of remediation strategies.

  6. Color flow mapping: a non-invasive tool for characterizing and differentiating between uveal melanomas and choroidal metastases.

    PubMed

    Neudorfer, Meira; Waisbourd, Michael; Anteby, Irene; Liran, Alon; Goldenberg, Dafna; Barak, Adiel; Kessler, Ada

    2011-01-01

    The objective of this study was to characterize and differentiate vascular patterns of choroidal melanomas and choroidal metastases by color flow mapping (CFM). We conducted a retrospective chart study on CFM findings in 18 patients with choroidal melanomas and 10 patients with choroidal metastases. We evaluated the possibilities of applying CFM to identify hypo- versus hyper-vascularity within the tumor, a central 'dominant vessel', and Doppler signals in the tumor's center and/or periphery. CFM demonstrated hypervascular patterns in 33% melanomas and 100% metastases (p<0.0001). CFM identified a central dominant vessel in 94% melanomas and 0/10 metastases (p<0.0001). Vascularity occupied the center of 11/18 melanomas and 0/10 metastases (p<0.0001), the periphery of 2/18 melanomas and 9/10 metastases (p<0.0001), and equally occupied the tumor's center and periphery of 5/18 melanomas and 1/10 metastases (p<0.0001). Based on our findings, we conclude that CFM was capable of non-invasively demonstrating different and distinct vascular patterns in malignant choroidal melanomas and choroidal metastases. PMID:21109962

  7. Creation and Characterization of an Ultrasound and CT Phantom for Non-invasive Ultrasound Thermometry Calibration

    PubMed Central

    Lai, Chun-Yen; Kruse, Dustin E.; Ferrara, Katherine W.; Caskey, Charles F.

    2014-01-01

    Ultrasound thermometry provides noninvasive two-dimensional (2-D) temperature monitoring, and in this paper, we have investigated the use of computed tomography (CT) radiodensity to characterize tissues to improve the accuracy of ultrasound thermometry. Agarose-based tissue-mimicking phantoms were created with glyceryl trioleate (a fat-mimicking material) concentration of 0, 10, 20, 30, 40, and 50%. The speed of sound (SOS) of the phantoms was measured over a temperature range of 22.1–41.1°C. CT images of the phantoms were acquired by a clinical dedicated breast CT scanner, followed by calculation of the Hounsfield units (HU). The phantom was heated with a therapeutic acoustic pulse (1.54 MHz), while RF data were acquired with a 10-MHz linear-array transducer. 2-D speckle tracking was used to calculate the thermal strain offline. The tissue dependent thermal strain parameter required for ultrasound thermometry was analyzed and correlated with CT radiodensity, followed by validation of the temperature prediction. Results showed that the change in SOS with the temperature increase was opposite in sign between the 0–10% and 20–50% trioleate phantoms. The inverse of the tissue dependent thermal strain parameter of the phantoms was correlated with the CT radiodensity (R2 = 0.99). A blinded ultrasound thermometry study on phantoms with a trioleate range of 5–35% demonstrated the capability to estimate the tissue dependent thermal strain parameter and estimate temperature with error less than ~1°C. In conclusion, CT radiodensity may provide a method for improving ultrasound thermometry in heterogeneous tissues. PMID:24107918

  8. Investigation of the potential of optical coherence tomography (OCT) as a non-invasive diagnostic tool in reproductive medicine

    NASA Astrophysics Data System (ADS)

    Trottmann, Matthias; Homann, Christian; Leeb, R.; Doering, D.; Kuznetsova, J.; Reese, S.; Stief, C. G.; Koelle, S.; Sroka, R.

    2015-02-01

    Introduction and objective: In Europe, nearly every sixth couple in the reproductive age is involuntarily childless. In about 30%, both male and female reveal fertility problems. In about 10% of infertile men, azoospermia is the underlying cause. As conventional therapeutic options are limited, surgical testicular sperm extraction (TESE) is necessary to obtain sperms for assisted reproductive techniques. Regarding the females, up to 30% of all idiopathic infertilities are due to alterations of the uterine tube So far, no imaging technique, which does not require any labelling, is available to evaluate the male and female genital tract at a microscopic level under in vivo conditions. Thus, the aim of this study was to investigate the potential of optical coherence tomography (OCT) as a non-invasive diagnostic tool in gynaecology and andrology. Material and Methods: Tissues samples from the bovine testis, epididymis, vas deferens, ovary, oviduct (ampulla and isthmus) and uterus were obtained immediately after slaughter (14 cows aged 3 to 8 years and 14 bulls aged 3 to 6 years; breeds: Holstein- Friesian, and Deutsches Fleckvieh). Imaging was done by using the US Food and Drug Administration (FDA) approved probe-based Niris Imaging System (Imalux, Cleveland, Ohio, USA) and the Telesto 1325 nm OCT System and Ganymede 930 nm OCT System (Thorlabs Inc., Dachau, Germany). All images obtained were compared to histological images after paraffin embedding and HE staining. Results: OCT imaging visualized the microarchitecture of the testis, epididymis, spermatic duct and the ovary, oviduct and uterus. Using the Thorlabs systems a axial resolution of approx. 5μm and lateral resolution of 8- 15μm could be achieved. Different optical tissue volumes could be visualized, which depends on the optical penetration depth of the wavelength of the system used. While the tissue volume observed by probe based Imalux-OCT is similar to the used Thorlabs systems, the optical resolution is

  9. An optical device employing multiwavelength photoplethysmography for non-invasive in-vivo monitoring of optically active nanoparticles

    NASA Astrophysics Data System (ADS)

    Michalak, Gregory J.; Adhikari, Pratik; Schwartz, Jon A.; Goodrich, Glenn P.; O'Neal, D. Patrick

    2011-03-01

    Researchers employ increasingly complex sub-micron particles for oncological applications to deliver bioactive therapeutic or imaging compounds to known and unknown in vivo tumor targets. These particles are often manufactured using a vast array of compounds and techniques resulting in a complex architecture, which can be quantified ex vivo by conventional metrology and chemical assays. In practice however, experimental homogeneity using nanoparticles can be difficult to achieve. While several imaging techniques have been previously shown to follow the accumulation of nanoparticles into tumor targets, a more rapid sensor that provides a quantifiable estimate of dose delivery and short-term systemic response could increase the clinical efficacy and greatly reduce the variability of these treatments. We have developed an optical device, the pulse photometer, that when placed on an accessible location will estimate the vascular concentration of near-infrared extinguishing nanoparticles in murine subjects. Using a technique called multi-wavelength photoplethysmography, the same technique used in pulse oximetry, our pulse photometer requires no baseline for each estimate allowing it to be taken on and off of the subject several times during experiments employing long circulating nanoparticles. We present a formal study of our prototype instrument in which circulation half-life and nanoparticle concentration of gold nanorods is determined in murine subjects with the aid of light anesthesia. In this study, we show good agreement between vascular nanorod concentrations (given in optical density) as determined by our device and with UV-VIS spectrophotometry using low volume blood samples.

  10. Use of optical pharmacokinetics systems (OPS) for non-invasive measurement of Phthalocyanine 4 (Pc 4) concentrations in mice bearing MDA-MB-231 xenografts

    NASA Astrophysics Data System (ADS)

    Bai, Lihua; Joseph, Erin; Olenick, Nancy L.; Mulvihill, John M.; Feyes, Denise K.; Eiseman, Julie L.

    2007-06-01

    Objective: Pc 4, a phthalocyanine photosensitizer in Phase I photodynamic therapy (PDT) trials, requires laser activation near 672 nm. For effective PDT, photosensitizer must be present in the target tissues. OPS uses elastic scattering spectroscopy to measure Pc 4 optical absorption non-invasively, and that absorbance can be converted to concentration using Pc 4 standard curves in 1% Intralipid®. In this study, we used OPS to evaluate Pc 4 optical absorption with time in subcutaneous tumor (with or without laser activation) and in contralateral skin. Tumor response was also evaluated after Pc 4-PDT. Conclusions: Both Pc 4 and hemoglobin optical absorption could be monitored by OPS. The decrease of Pc 4 absorption after PDT and the appearance of d-hbg indicated that alterations occurred in the tumor following Pc 4-PDT. The increase in d-hbg suggests that oxygen was not replaced completely, possibly due to circulation damage in tumor.

  11. Non-Invasive Optical Imaging of Eosinophilia during the Course of an Experimental Allergic Airways Disease Model and in Response to Therapy

    PubMed Central

    Markus, M. Andrea; Dullin, Christian; Mitkovski, Miso; Prieschl-Grassauer, Eva; Epstein, Michelle M.; Alves, Frauke

    2014-01-01

    Background Molecular imaging of lung diseases, including asthma, is limited and either invasive or non-specific. Central to the inflammatory process in asthma is the recruitment of eosinophils to the airways, which release proteases and proinflammatory factors and contribute to airway remodeling. The aim of this study was to establish a new approach to non-invasively assess lung eosinophilia during the course of experimental asthma by combining non-invasive near-infrared fluorescence (NIRF) imaging with the specific detection of Siglec-F, a lectin found predominantly on eosinophils. Methodology/Principal Findings An ovalbumin (OVA)-based model was used to induce asthma-like experimental allergic airway disease (EAAD) in BALB/c mice. By means of a NIRF imager, we demonstrate that 48 h–72 h after intravenous (i.v.) application of a NIRF-labeled anti-Siglec-F antibody, mice with EAAD exhibited up to 2 times higher fluorescence intensities compared to lungs of control mice. Furthermore, average lung intensities of dexamethasone-treated as well as beta-escin-treated mice were 1.8 and 2 times lower than those of untreated, EAAD mice, respectively and correlated with the reduction of cell infiltration in the lung. Average fluorescence intensities measured in explanted lungs confirmed the in vivo findings of significantly higher values in inflamed lungs as compared to controls. Fluorescence microscopy of lung cryosections localized the i.v. applied NIRF-labeled anti-Siglec-F antibody predominantly to eosinophils in the peribronchial areas of EAAD lungs as opposed to control lungs. Conclusion/Significance We show that monitoring the occurrence of eosinophils, a prominent feature of allergic asthma, by means of a NIRF-labeled antibody directed against Siglec-F is a novel and powerful non-invasive optical imaging approach to assess EAAD and therapeutic response in mice over time. PMID:24587190

  12. Characterization of small microsatellite loci isolated in endangered Indiana bat (Myotis sodalis) for use in non-invasive sampling

    USGS Publications Warehouse

    Oyler-McCance, Sara J.; Fike, Jennifer A.

    2011-01-01

    Primers for 10 microsatellite loci were developed specifically to amplify low quantity and quality DNA in the endangered Indiana Bat (Myotis sodalis). In a screen of 20 individuals from a population in Missouri, the 10 loci were found to have levels of variability ranging from seven to 18 alleles. No loci were found to be linked, although two loci revealed significant departures from Hardy–Weinberg equilibrium. These microsatellite loci will be applicable for population genetic analyses and for use in mark-recapture studies that utilize DNA collected non-invasively from fecal pellets, which will ultimately aid in management efforts.

  13. Breast Tissue Composition and Its Dependence on Demographic Risk Factors for Breast Cancer: Non-Invasive Assessment by Time Domain Diffuse Optical Spectroscopy

    PubMed Central

    Taroni, Paola; Quarto, Giovanna; Pifferi, Antonio; Abbate, Francesca; Balestreri, Nicola; Menna, Simona; Cassano, Enrico; Cubeddu, Rinaldo

    2015-01-01

    Background Breast tissue composition is recognized as a strong and independent risk factor for breast cancer. It is a heritable feature, but is also significantly affected by several other elements (e.g., age, menopause). Nowadays it is quantified by mammographic density, thus requiring the use of ionizing radiation. Optical techniques are absolutely non-invasive and have already proved effective in the investigation of biological tissues, as they are sensitive to tissue composition and structure. Methods Time domain diffuse optical spectroscopy was performed at 7 wavelengths (635-1060 nm) on 200 subjects to derive their breast tissue composition (in terms of water, lipid and collagen content), blood parameters (total hemoglobin content and oxygen saturation level), and information on the microscopic structure (scattering amplitude and power). The dependence of all optically-derived parameters on age, menopausal status, body mass index, and use of oral contraceptives, and the correlation with mammographic density were investigated. Results Younger age, premenopausal status, lower body mass index values, and use of oral contraceptives all correspond to significantly higher water, collagen and total hemoglobin content, and lower lipid content (always p < 0.05 and often p < 10-4), while oxygen saturation level and scattering parameters show significant dependence only on some conditions. Even when age-adjusted groups of subjects are compared, several optically derived parameters (and in particular always collagen and total hemoglobin content) remain significantly different. Conclusions Time domain diffuse optical spectroscopy can probe non-invasively breast tissue composition and physiologic blood parameters, and provide information on tissue structure. The measurement is suitable for in vivo studies and monitoring of changes in breast tissue (e.g., with age, lifestyle, chemotherapy, etc.) and to gain insight into related processes, like the origin of cancer risk

  14. Eco-photonics: application of optical diagnostic modalities for non-invasive monitoring and evaluation of stress conditions of aquatic organisms

    NASA Astrophysics Data System (ADS)

    Gurkov, A. N.; Axenov-Gribanov, D. V.; Pavlichenko, V. V.; Shakhtanova, N. S.; Bedulina, D. S.; Timofeyev, M. A.; Kalchenko, V.; Meglinski, I.

    2012-03-01

    The growing interest in monitoring ecological change has been stimulated by a global climate change, combined with the day-to-day human anthropogenic activities, that heavily influence the environment. A global warming accompanied by a anthropogenic activities falling within the freshwater ecosystem result a dramatic enhance of the overall stress for most of aquatic organisms. We explore the applicability of optical spectroscopy and advanced non-invasive imaging techniques, that have been used earlier in various biomedical applications, to study an influence of climatic changes on the physiological and biochemical processes that take place in living aquatic organisms. In current report we demonstrate that optical spectroscopy and modern imaging techniques can be successfully used to observe and evaluate thermal and/or hypoxic stress, experienced by freshwater organisms, such as Baikal amphipods.

  15. High-resolution harmonics ultrasound imaging for non-invasive characterization of wound healing in a pre-clinical swine model.

    PubMed

    Gnyawali, Surya C; Barki, Kasturi G; Mathew-Steiner, Shomita S; Dixith, Sriteja; Vanzant, Daniel; Kim, Jayne; Dickerson, Jennifer L; Datta, Soma; Powell, Heather; Roy, Sashwati; Bergdall, Valerie; Sen, Chandan K

    2015-01-01

    This work represents the first study employing non-invasive high-resolution harmonic ultrasound imaging to longitudinally characterize skin wound healing. Burn wounds (day 0-42), on the dorsum of a domestic Yorkshire white pig were studied non-invasively using tandem digital planimetry, laser speckle imaging and dual mode (B and Doppler) ultrasound imaging. Wound depth, as measured by B-mode imaging, progressively increased until day 21 and decreased thereafter. Initially, blood flow at the wound edge increased up to day 14 and subsequently regressed to baseline levels by day 21, when the wound was more than 90% closed. Coinciding with regression of blood flow at the wound edge, there was an increase in blood flow in the wound bed. This was observed to regress by day 42. Such changes in wound angiogenesis were corroborated histologically. Gated Doppler imaging quantitated the pulse pressure of the primary feeder artery supplying the wound site. This pulse pressure markedly increased with a bimodal pattern following wounding connecting it to the induction of wound angiogenesis. Finally, ultrasound elastography measured tissue stiffness and visualized growth of new tissue over time. These studies have elegantly captured the physiological sequence of events during the process of wound healing, much of which is anticipated based on certain dynamics in play, to provide the framework for future studies on molecular mechanisms driving these processes. We conclude that the tandem use of non-invasive imaging technologies has the power to provide unprecedented insight into the dynamics of the healing skin tissue. PMID:25799513

  16. High-Resolution Harmonics Ultrasound Imaging for Non-Invasive Characterization of Wound Healing in a Pre-Clinical Swine Model

    PubMed Central

    Mathew-Steiner, Shomita S.; Dixith, Sriteja; Vanzant, Daniel; Kim, Jayne; Dickerson, Jennifer L.; Datta, Soma; Powell, Heather; Roy, Sashwati; Bergdall, Valerie; Sen, Chandan K.

    2015-01-01

    This work represents the first study employing non-invasive high-resolution harmonic ultrasound imaging to longitudinally characterize skin wound healing. Burn wounds (day 0-42), on the dorsum of a domestic Yorkshire white pig were studied non-invasively using tandem digital planimetry, laser speckle imaging and dual mode (B and Doppler) ultrasound imaging. Wound depth, as measured by B-mode imaging, progressively increased until day 21 and decreased thereafter. Initially, blood flow at the wound edge increased up to day 14 and subsequently regressed to baseline levels by day 21, when the wound was more than 90% closed. Coinciding with regression of blood flow at the wound edge, there was an increase in blood flow in the wound bed. This was observed to regress by day 42. Such changes in wound angiogenesis were corroborated histologically. Gated Doppler imaging quantitated the pulse pressure of the primary feeder artery supplying the wound site. This pulse pressure markedly increased with a bimodal pattern following wounding connecting it to the induction of wound angiogenesis. Finally, ultrasound elastography measured tissue stiffness and visualized growth of new tissue over time. These studies have elegantly captured the physiological sequence of events during the process of wound healing, much of which is anticipated based on certain dynamics in play, to provide the framework for future studies on molecular mechanisms driving these processes. We conclude that the tandem use of non-invasive imaging technologies has the power to provide unprecedented insight into the dynamics of the healing skin tissue. PMID:25799513

  17. Non-invasive characterization of the adipogenic differentiation of human bone marrow-derived mesenchymal stromal cells by HS-SPME/GC-MS

    PubMed Central

    Lee, Dong-Kyu; Yi, TacGhee; Park, Kyung-Eun; Lee, Hyun-Joo; Cho, Yun-Kyoung; Lee, Seul Ji; Lee, Jeongmi; Park, Jeong Hill; Lee, Mi-Young; Song, Sun U.; Kwon, Sung Won

    2014-01-01

    A non-invasive method to characterize human mesenchymal stromal cells during adipogenic differentiation was developed for the first time. Seven fatty acid methyl esters (FAMEs), including methyl laurate, methyl myristate, methyl palmitate, methyl linoleate, methyl oleate, methyl elaidate and methyl stearate, were used for characterizing adipogenic differentiation using headspace solid-phase microextraction (HS-SPME) which is a very simple and non-invasive method for the extraction of volatile compounds. Glassware was used for culturing mesenchymal stromal cells rather than the common plasticware to minimize contamination by volatile impurities. The optimal SPME fiber was selected by comparing diverse fibers containing two pure liquid polymers (PDMS and PA) and two porous solids (PDMS/DVB and CAR/PDMS). Using optimized procedures, we discovered that seven FAMEs were only detected in adipogenic differentiated mesenchymal stromal cells and not in the mesenchymal stromal cells before differentiation. These data could support the quality control of clinical mesenchymal stromal cell culture in the pharmaceutical industry in addition to the development of many clinical applications using mesenchymal stromal cells. PMID:25298091

  18. Non-invasive characterization of the adipogenic differentiation of human bone marrow-derived mesenchymal stromal cells by HS-SPME/GC-MS.

    PubMed

    Lee, Dong-Kyu; Yi, TacGhee; Park, Kyung-Eun; Lee, Hyun-Joo; Cho, Yun-Kyoung; Lee, Seul Ji; Lee, Jeongmi; Park, Jeong Hill; Lee, Mi-Young; Song, Sun U; Kwon, Sung Won

    2014-01-01

    A non-invasive method to characterize human mesenchymal stromal cells during adipogenic differentiation was developed for the first time. Seven fatty acid methyl esters (FAMEs), including methyl laurate, methyl myristate, methyl palmitate, methyl linoleate, methyl oleate, methyl elaidate and methyl stearate, were used for characterizing adipogenic differentiation using headspace solid-phase microextraction (HS-SPME) which is a very simple and non-invasive method for the extraction of volatile compounds. Glassware was used for culturing mesenchymal stromal cells rather than the common plasticware to minimize contamination by volatile impurities. The optimal SPME fiber was selected by comparing diverse fibers containing two pure liquid polymers (PDMS and PA) and two porous solids (PDMS/DVB and CAR/PDMS). Using optimized procedures, we discovered that seven FAMEs were only detected in adipogenic differentiated mesenchymal stromal cells and not in the mesenchymal stromal cells before differentiation. These data could support the quality control of clinical mesenchymal stromal cell culture in the pharmaceutical industry in addition to the development of many clinical applications using mesenchymal stromal cells. PMID:25298091

  19. Non-invasive blood glucose measurement by Fourier transform infrared spectroscopic analysis through the mucous membrane of the lip: application of a chalcogenide optical fiber system.

    PubMed

    Uemura, T; Nishida, K; Sakakida, M; Ichinose, K; Shimoda, S; Shichiri, M

    1999-01-01

    Non-invasive blood glucose measurement through the mucous membrane of the lip was investigated using Fourier transform infrared (FT-IR) spectroscopy with an attenuated total reflection (ATR) prism. To achieve easy attachment and easy control of attachment pressure of the ATR prism to the mucous membrane of the lip, a chalcogenide optical fiber with an ATR prism built in the tip was used. The same glucose-specific peaks at wave numbers of 1080 and 1033 cm-1 as glucose solutions were found in a spectrum through the mucous membrane of the lip. With a constant pressure of the ATR prism to the mucous membrane of the lip of 6.7 x 10(3) dyn/cm2, coefficients of variation of measurements within the day and of day-to-day measurements were 3.8 and 5.4% respectively. To eliminate baseline drifts and interference of body constituents other than glucose, the difference absorbances at 1080 cm-1 between spectra measured at the postprandial state and background spectrum obtained at the fasting state as an individual characteristic were evaluated. Following i.v. pulsatile injection of glucose, the difference absorbances at 1080 cm-1 nicely followed the changes in blood glucose concentrations with a time delay of 4 min. In daily blood glucose monitoring, a highly significant correlation between the difference absorbances and increases in blood glucose concentrations above the fasting level was obtained (r = 0.920, P < 0.01). From these experiments, it was suggested that FT-IR spectroscopy with a chalcogenide optical fiber could be useful clinically for non-invasive monitoring of glucose through the mucous membrane of the lip. PMID:10450500

  20. Non-invasive and invasive imaging of vulnerable coronary plaque.

    PubMed

    Celeng, Csilla; Takx, Richard A P; Ferencik, Maros; Maurovich-Horvat, Pál

    2016-08-01

    Vulnerable plaque is characterized by a large necrotic core and an overlying thin fibrous cap. Non-invasive imaging modalities such as computed tomography angiography (CTA) and magnetic resonance imaging (MRI) allow for the assessment of morphological plaque characteristics, while positron emission tomography (PET) enables the detection of metabolic activity within the atherosclerotic lesions. Invasive imaging modalities such as intravascular ultrasound (IVUS), optical-coherence tomography (OCT), and intravascular MRI (IV-MRI) display plaques at a high spatial resolution. Near-infrared spectroscopy (NIRS) allows for the detection of chemical components of atherosclerotic plaques. In this review, we describe state-of-the-art non-invasive and invasive imaging modalities and stress the combination of their advantages to identify vulnerable plaque features. PMID:27079893

  1. Non-invasive sensing for food reassurance.

    PubMed

    Xiaobo, Zou; Xiaowei, Huang; Povey, Malcolm

    2016-03-01

    Consumers and governments are increasingly interested in the safety, authenticity and quality of food commodities. This has driven attention towards non-invasive sensing techniques used for rapid analyzing these commodities. This paper provides an overview of the state of the art in, and available alternatives for, food assurance based on non-invasive sensing techniques. The main food quality traits of interest using non-invasive sensing techniques are sensory characteristics, chemical composition, physicochemical properties, health-protecting properties, nutritional characteristics and safety. A wide range of non-invasive sensing techniques, from optical, acoustical, electrical, to nuclear magnetic, X-ray, biosensor, microwave and terahertz, are organized according to physical principle. Some of these techniques are now in a period of transition between experimental and applied utilization and several sensors and instruments are reviewed. With continued innovation and attention to key challenges, such non-invasive sensors and biosensors are expected to open up new exciting avenues in the field of portable and wearable wireless sensing devices and connecting with mobile networks, thus finding considerable use in a wide range of food assurance applications. The need for an appropriate regulatory framework is emphasized which acts to exclude unwanted components in foods and includes needed components, with sensors as part of a reassurance framework supporting regulation and food chain management. The integration of these sensor modalities into a single technological and commercial platform offers an opportunity for a paradigm shift in food reassurance. PMID:26835653

  2. Two-layer optical model of skin for early, non-invasive detection of wound development on the diabetic foot

    NASA Astrophysics Data System (ADS)

    Yudovsky, Dmitry; Nouvong, Aksone; Schomacker, Kevin; Pilon, Laurent

    2010-02-01

    Foot ulceration is a debilitating comorbidity of diabetes that may result in loss of mobility and amputation. Optical detection of cutaneous tissue changes due to inflammation and necrosis at the preulcer site could constitute a preventative strategy. A commercial hyperspectral oximetry system was used to measure tissue oxygenation on the feet of diabetic patients. A previously developed predictive index was used to differentiate preulcer tissue from surrounding healthy tissue with a sensitivity of 92% and specificity of 80%. To improve prediction accuracy, an optical skin model was developed treating skin as a two-layer medium and explicitly accounting for (i) melanin content and thickness of the epidermis, (ii) blood content and hemoglobin saturation of the dermis, and (iii) tissue scattering in both layers. Using this forward model, an iterative inverse method was used to determine the skin properties from hyperspectral images of preulcerative areas. The use of this information in lowering the false positive rate was discussed.

  3. Non-invasive assessment of intracranial pressure.

    PubMed

    Robba, C; Bacigaluppi, S; Cardim, D; Donnelly, J; Bertuccio, A; Czosnyka, M

    2016-07-01

    Monitoring of intracranial pressure (ICP) is invaluable in the management of neurosurgical and neurological critically ill patients. Invasive measurement of ventricular or parenchymal pressure is considered the gold standard for accurate measurement of ICP but is not always possible due to certain risks. Therefore, the availability of accurate methods to non-invasively estimate ICP has the potential to improve the management of these vulnerable patients. This review provides a comparative description of different methods for non-invasive ICP measurement. Current methods are based on changes associated with increased ICP, both morphological (assessed with magnetic resonance, computed tomography, ultrasound, and fundoscopy) and physiological (assessed with transcranial and ophthalmic Doppler, tympanometry, near-infrared spectroscopy, electroencephalography, visual-evoked potentials, and otoacoustic emissions assessment). At present, none of the non-invasive techniques alone seem suitable as a substitute for invasive monitoring. However, following the present analysis and considerations upon each technique, we propose a possible flowchart based on the combination of non-invasive techniques including those characterizing morphologic changes (e.g., repetitive US measurements of ONSD) and those characterizing physiological changes (e.g., continuous TCD). Such an integrated approach, which still needs to be validated in clinical practice, could aid in deciding whether to place an invasive monitor, or how to titrate therapy when invasive ICP measurement is contraindicated or unavailable. PMID:26515159

  4. Using non-invasive methods to characterize gonadal hormonal patterns of southern three-banded armadillos (Tolypeutes matacus) housed in North American zoos.

    PubMed

    Howell-Stephens, J; Bernier, D; Brown, J S; Mulkerin, D; Santymire, R M

    2013-05-01

    Understanding the basic reproductive biology and limitations to successful breeding of the southern three-banded armadillo (Tolypeutes matacus) is necessary to maintain viable zoo populations. Our objectives were to: 1) describe the reproductive biology using non-invasive, fecal hormone analysis; 2) assess influence of season on gonadal hormonal patterns in both the sexes; 3) characterize reproductive cyclicity and pregnancy in the female; and 4) characterize the onset of sexual maturity in males. Nineteen armadillos were monitored including: 13 (7 males, 6 females) from Lincoln Park Zoo and six (3 males, 3 females) from San Antonio Zoological Garden. Fecal samples (n=5220; 275/animal/yr) were collected 5 to 7 times a week for 1 year. Hormones were extracted from feces and analyzed for progestagen (females) and androgen (males) metabolite concentrations using enzyme immunoassays. Mean estrous cycle length (26.4±1.3 days) did not vary (P<0.05) among individuals (n=9). Mean gestation length (n=3) was 114.0±0.6 days long with mean fecal progestagen metabolites increasing 10-fold during pregnancy. Seasons did not influence (P<0.05) fecal androgen or progestagen metabolites. These data can assist with management decisions, which will directly affect the success of this species in zoos. PMID:23541612

  5. Comparative analysis of gingival phenotype in animal and human experimental models using optical coherence tomography in a non-invasive approach

    NASA Astrophysics Data System (ADS)

    Mota, Cláudia C. B. O.; Fernandes, Luana O.; Melo, Luciana S. A.; Feitosa, Daniela S.; Cimões, Renata; Gomes, Anderson S. L.

    2015-06-01

    Imaging methods are widely used in diagnostic and among the diversity of modalities, optical coherence tomography (OCT) is nowadays commercially available and considered the most innovative technique used for imaging applications, in both medical and non-medical applications. In this study, we exploit the OCT technique in the oral cavity for identification and differentiation between free and attached gingiva, as well as determining the gingival phenotype, an important factor to determination of periodontal prognosis in patients. For the animal studies, five porcine jaws were analyzed using a Swept Source SS-OCT system operating at 1325nm and stereomicroscope, as gold pattern. The SSOCT at 1325nm was chosen due to the longer central wavelength, that allows to deeper penetration imaging, and the faster image acquisition, an essential factor for clinical setting. For the patient studies, a total of 30 males and female were examined using the SS-OCT at 1325nm and computer controlled periodontal probing. 2D and 3D images of tooth/gingiva interface were performed, and quantitative measurements of the gingival sulcus could be noninvasively obtained. Through the image analysis of the animals jaws, it was possible to quantify the free gingiva and the attached gingiva, the calculus deposition over teeth surface and also the subgingival calculus. For the patient's studies, we demonstrated that the gingival phenotype could be measured without the periodontal probe introduction at the gingival sulcus, confirming that OCT can be potentially useful in clinic for direct observation and quantification of gingival phenotype in a non-invasive approach.

  6. Characterization of Artifacts Produced by Gel Displacement on Non-invasive Brain-Machine Interfaces during Ambulation.

    PubMed

    Costa, Álvaro; Salazar-Varas, Rocio; Úbeda, Andrés; Azorín, José M

    2016-01-01

    So far, Brain-Machine Interfaces (BMIs) have been mainly used to study brain potentials during movement-free conditions. Recently, due to the emerging concern of improving rehabilitation therapies, these systems are also being used during gait experiments. Under this new condition, the evaluation of motion artifacts has become a critical point to assure the validity of the results obtained. Due to the high signal to noise ratio provided, the use of wet electrodes is a widely accepted technic to acquire electroencephalographic (EEG signals). To perform these recordings it is necessary to apply a conductive gel between the scalp and the electrodes. This work is focused on the study of gel displacements produced during ambulation and how they affect the amplitude of EEG signals. Data recorded during three ambulation conditions (gait training) and one movement-free condition (BMI motor imagery task) are compared to perform this study. Two phenomenons, manifested as unusual increases of the signals' amplitude, have been identified and characterized during this work. Results suggest that they are caused by abrupt changes on the conductivity between the electrode and the scalp due to gel displacement produced during ambulation and head movements. These artifacts significantly increase the Power Spectral Density (PSD) of EEG recordings at all frequencies from 5 to 90 Hz, corresponding to the main bandwidth of electrocortical potentials. They should be taken into consideration before performing EEG recordings in order to asses the correct gel allocation and to avoid the use of electrodes on certain scalp areas depending on the experimental conditions. PMID:26941601

  7. Characterization of Artifacts Produced by Gel Displacement on Non-invasive Brain-Machine Interfaces during Ambulation

    PubMed Central

    Costa, Álvaro; Salazar-Varas, Rocio; Úbeda, Andrés; Azorín, José M.

    2016-01-01

    So far, Brain-Machine Interfaces (BMIs) have been mainly used to study brain potentials during movement-free conditions. Recently, due to the emerging concern of improving rehabilitation therapies, these systems are also being used during gait experiments. Under this new condition, the evaluation of motion artifacts has become a critical point to assure the validity of the results obtained. Due to the high signal to noise ratio provided, the use of wet electrodes is a widely accepted technic to acquire electroencephalographic (EEG signals). To perform these recordings it is necessary to apply a conductive gel between the scalp and the electrodes. This work is focused on the study of gel displacements produced during ambulation and how they affect the amplitude of EEG signals. Data recorded during three ambulation conditions (gait training) and one movement-free condition (BMI motor imagery task) are compared to perform this study. Two phenomenons, manifested as unusual increases of the signals' amplitude, have been identified and characterized during this work. Results suggest that they are caused by abrupt changes on the conductivity between the electrode and the scalp due to gel displacement produced during ambulation and head movements. These artifacts significantly increase the Power Spectral Density (PSD) of EEG recordings at all frequencies from 5 to 90 Hz, corresponding to the main bandwidth of electrocortical potentials. They should be taken into consideration before performing EEG recordings in order to asses the correct gel allocation and to avoid the use of electrodes on certain scalp areas depending on the experimental conditions. PMID:26941601

  8. Non-invasive characterization of polyurethane-based tissue constructs in a rat abdominal repair model using high frequency ultrasound elasticity imaging.

    PubMed

    Yu, Jiao; Takanari, Keisuke; Hong, Yi; Lee, Kee-Won; Amoroso, Nicholas J; Wang, Yadong; Wagner, William R; Kim, Kang

    2013-04-01

    The evaluation of candidate materials and designs for soft tissue scaffolds would benefit from the ability to monitor the mechanical remodeling of the implant site without the need for periodic animal sacrifice and explant analysis. Toward this end, the ability of non-invasive ultrasound elasticity imaging (UEI) to assess temporal mechanical property changes in three different types of porous, biodegradable polyurethane scaffolds was evaluated in a rat abdominal wall repair model. The polymers utilized were salt-leached scaffolds of poly(carbonate urethane) urea, poly(ester urethane) urea and poly(ether ester urethane) urea at 85% porosity. A total of 60 scaffolds (20 each type) were implanted in a full thickness muscle wall replacement in the abdomens of 30 rats. The constructs were ultrasonically scanned every 2 weeks and harvested at weeks 4, 8 and 12 for compression testing or histological analysis. UEI demonstrated different temporal stiffness trends among the different scaffold types, while the stiffness of the surrounding native tissue remained unchanged. The changes in average normalized strains developed in the constructs from UEI compared well with the changes of mean compliance from compression tests and histology. The average normalized strains and the compliance for the same sample exhibited a strong linear relationship. The ability of UEI to identify herniation and to characterize the distribution of local tissue in-growth with high resolution was also investigated. In summary, the reported data indicate that UEI may allow tissue engineers to sequentially evaluate the progress of tissue construct mechanical behavior in vivo and in some cases may reduce the need for interim time point animal sacrifice. PMID:23347836

  9. Non-invasive Characterization of Polyurethane-based Tissue Constructs in a Rat Abdominal Repair Model Using High Frequency Ultrasound Elasticity Imaging

    PubMed Central

    Yu, Jiao; Takanari, Keisuke; Hong, Yi; Lee, Kee-Won; Amoroso, Nicholas J.; Wang, Yadong; Wagner, William R.; Kim, Kang

    2013-01-01

    The evaluation of candidate materials and designs for soft tissue scaffolds would benefit from the ability to monitor the mechanical remodeling of the implant site without the need for periodic animal sacrifice and explant analysis. Toward this end, the ability of non-invasive ultrasound elasticity imaging (UEI) to assess temporal mechanical property changes in three different types of porous, biodegradable polyurethane scaffolds was evaluated in a rat abdominal wall repair model. The polymers utilized were salt-leached scaffolds of poly(carbonate urethane) urea, poly(ester urethane) urea and poly(ether ester urethane) urea at 85% porosity. A total of 60 scaffolds (20 each type) were implanted in a full thickness muscle wall replacement in the abdomens of 30 rats. The constructs were ultrasonically scanned every 2 weeks and harvested at weeks 4, 8 and 12 for compression testing or histological analysis. UEI demonstrated different temporal stiffness trends among the different scaffold types, while the stiffness of the surrounding native tissue remained unchanged. The changes in average normalized strains developed in the constructs from UEI compared well with the changes of mean compliance from compression tests and histology. The average normalized strains and the compliance for the same sample exhibited a strong linear relationship. The ability of UEI to identify herniation and to characterize the distribution of local tissue in-growth with high resolution was also investigated. In summary, the reported data indicate that UEI may allow tissue engineers to sequentially evaluate the progress of tissue construct mechanical behavior in vivo and in some cases may reduce the need for interim time point animal sacrifice. PMID:23347836

  10. Non-invasive physiological measurements

    SciTech Connect

    Rolfe, P.

    1983-01-01

    This book discusses the diagnostic techniques of nondestructive type for monitoring the physiology of various organ systems. The topics covered are: non-invasive assessment of gastric activity; uterine activity, intestinal activity; monitoring of fetal cardiovascular system and bilirubin physiology of infants. Respiratory system of infants is monitored and ultrasonography of heart is discussed.

  11. Ultrahigh-speed non-invasive widefield angiography

    NASA Astrophysics Data System (ADS)

    Blatter, Cedric; Klein, Thomas; Grajciar, Branislav; Schmoll, Tilman; Wieser, Wolfgang; Andre, Raphael; Huber, Robert; Leitgeb, Rainer A.

    2012-07-01

    Retinal and choroidal vascular imaging is an important diagnostic benefit for ocular diseases such as age-related macular degeneration. The current gold standard for vessel visualization is fluorescence angiography. We present a potential non-invasive alternative to image blood vessels based on functional Fourier domain optical coherence tomography (OCT). For OCT to compete with the field of view and resolution of angiography while maintaining motion artifacts to a minimum, ultrahigh-speed imaging has to be introduced. We employ Fourier domain mode locking swept source technology that offers high quality imaging at an A-scan rate of up to 1.68 MHz. We present retinal angiogram over ˜48 deg acquired in a few seconds in a single recording without the need of image stitching. OCT at 1060 nm allows for high penetration in the choroid and efficient separate characterization of the retinal and choroidal vascularization.

  12. Effect of Injector Geometry on Atomization of a Liquid-Liquid Double Swirl Coaxial Injector using Non-Invasive Laser, Optical and X-ray Techniques

    NASA Technical Reports Server (NTRS)

    Radke, C. R.; Meyer, T. R.

    2014-01-01

    The spray characteristics of a Liquid-Liquid Double Swirl Coaxial Injector were studied using noninvasive Optical, Laser, and X-ray diagnostics. A parametric study of injector exit geometry demonstrated that spray breakup time, breakup type and sheet stability could be controlled with exit geometry. Phase Doppler Particle Analysis characterized droplet statistics and non-dimensional droplet parameters over a range of inlet conditions and for various fluids allowing for a study on the role of specific fluid properties in atomization. Further, x-ray radiographs allowed for investigations of sheet thickness and breakup length to be quantified for different recess exits and inlet pressures. Finally Computed Tomography scans revealed that the spray cone was distinctively non-uniform and comprised of several pockets of increased mass flux.

  13. Study of turbocharger shaft motion by means of non-invasive optical techniques: Application to the behaviour analysis in turbocharger lubrication failures

    NASA Astrophysics Data System (ADS)

    Pastor, J. V.; Serrano, J. R.; Dolz, V.; López, M. A.; Bouffaud, F.

    2012-10-01

    This paper presents a novel non-invasive technique to estimate the turbocharger shaft whirl motion. The aim of this article is to present a system for monitoring the shaft motion of a turbocharger, which will be used in turbocharger destructive testing. To achieve this, a camera and a light source were installed in a turbocharger test bench with a controlled lubrication circuit. An image recording methodology and a process algorithm have been developed, in order to estimate the shaft motion. This processing consists on differentiating specific zones of the image, in order to obtain their coordinates. Two reference points have been configured on the compressor side, which help to calculate the relative position of the shaft, avoiding the errors due to structural vibrations. Maximum eccentricity of the turbocharger has been determined and it has been compared with shaft motion when it is spinning in different conditions. A luminosity study has been also done, in order to improve the process and to obtain locus of shaft position in a picture exposition time period. The technique has been applied to diagnosis of a lubrication failure test and the main results will be presented in this article: like shaft motion figures; thermodynamic variables and pictures of the shaft while it is spinning at abnormal lubrication conditions. The measuring components used in this technique have the ability to withstand the catastrophic failure of the turbocharger in this type of test.

  14. Non-invasive glucose monitor

    NASA Technical Reports Server (NTRS)

    Lambert, James L. (Inventor); Borchert, Mark S. (Inventor)

    2001-01-01

    A non-invasive method for determining blood level of an analyte of interest, such as glucose, comprises: generating an excitation laser beam (e.g., at a wavelength of 700 to 900 nanometers); focusing the excitation laser beam into the anterior chamber of an eye of the subject so that aqueous humor in the anterior chamber is illuminated; detecting (preferably confocally detecting) a Raman spectrum from the illuminated aqueous humor; and then determining the blood glucose level (or the level of another analyte of interest) for the subject from the Raman spectrum. Preferably, the detecting step is followed by the step of subtracting a confounding fluorescence spectrum from the Raman spectrum to produce a difference spectrum; and determining the blood level of the analyte of interest for the subject from that difference spectrum, preferably using linear or nonlinear multivariate analysis such as partial least squares analysis. Apparatus for carrying out the foregoing method is also disclosed.

  15. Non-invasive in vivo measurement of macular carotenoids

    NASA Technical Reports Server (NTRS)

    Lambert, James L. (Inventor); Borchert, Mark S. (Inventor)

    2009-01-01

    A non-invasive in vivo method for assessing macular carotenoids includes performing Optical Coherence Tomography (OCT) on a retina of a subject. A spatial representation of carotenoid levels in the macula based on data from the OCT of the retina can be generated.

  16. Non-invasive method of measuring cerebral spinal fluid pressure

    NASA Technical Reports Server (NTRS)

    Borchert, Mark S. (Inventor); Lambert, James L. (Inventor)

    2000-01-01

    The invention provides a method of non-invasively determining intracranial pressure from measurements of an eye. A parameter of an optic nerve of the eye is determined, along with an intraocular pressure of the eye. The intracranial pressure may be determined from the intraocular pressure and the parameter.

  17. Characterization of MHC class II B polymorphism in multiple populations of wild gorillas using non-invasive samples and next-generation sequencing.

    PubMed

    Hans, Jörg B; Haubner, Anne; Arandjelovic, Mimi; Bergl, Richard A; Fünfstück, Tillmann; Gray, Maryke; Morgan, David B; Robbins, Martha M; Sanz, Crickette; Vigilant, Linda

    2015-11-01

    Genes encoded by the major histocompatibility complex (MHC) are crucial for the recognition and presentation of antigens to the immune system. In contrast to their closest relatives, chimpanzees and humans, much less is known about variation in gorillas at these loci. This study explored the exon 2 variation of -DPB1, -DQB1, and -DRB genes in 46 gorillas from four populations while simultaneously evaluating the feasibility of using fecal samples for high-throughput MHC genotyping. By applying strict similarity- and frequency-based analysis, we found, despite our modest sample size, a total of 18 alleles that have not been described previously, thereby illustrating the potential for efficient and highly accurate MHC genotyping from non-invasive DNA samples. We emphasize the importance of controlling for multiple potential sources of error when applying this massively parallel short-read sequencing technology to PCR products generated from low concentration DNA extracts. We observed pronounced differences in MHC variation between species, subspecies and populations that are consistent with both the ancient and recent demographic histories experienced by gorillas. PMID:26283172

  18. A non-invasive method for detecting the metabolic stress response in rodents: characterization and disruption of the circadian corticosterone rhythm.

    PubMed

    Thanos, P K; Cavigelli, S A; Michaelides, M; Olvet, D M; Patel, U; Diep, M N; Volkow, N D

    2009-01-01

    Plasma corticosterone (CORT) measures are a common procedure to detect stress responses in rodents. However, the procedure is invasive and can influence CORT levels, making it less than ideal for monitoring CORT circadian rhythms. In the current paper, we examined the applicability of a non-invasive fecal CORT metabolite measure to assess the circadian rhythm. We compared fecal CORT metabolite levels to circulating CORT levels, and analyzed change in the fecal circadian rhythm following an acute stressor (i.e. blood sampling by tail veil catheter). Fecal and blood samples were collected from male adolescent rats and analyzed for CORT metabolites and circulating CORT respectively. Fecal samples were collected hourly for 24 h before and after blood draw. On average, peak fecal CORT metabolite values occurred 7-9 h after the plasma CORT peak and time-matched fecal CORT values were well correlated with plasma CORT. As a result of the rapid blood draw, fecal production and CORT levels were altered the next day. These results indicate fecal CORT metabolite measures can be used to assess conditions that disrupt the circadian CORT rhythm, and provide a method to measure long-term changes in CORT production. This can benefit research that requires long-term glucocorticoid assessment (e.g. stress mechanisms underlying health). PMID:18380537

  19. A Non-Invasive Method for Detecting the Metabolic Stress Response in Rodents: Characterization and Disruption of the Circadian Corticosterone Rhythm

    PubMed Central

    Thanos, Panayotis K.; Cavigelli, Sonia A.; Michaelides, Michael; Olvet, Doreen M.; Patel, Ujval; Diep, Mai N.; Volkow, Nora D.

    2009-01-01

    1. Summary Plasma corticosterone (CORT) measures are a common procedure to detect stress responses in rodents. However, the procedure is invasive and can influence CORT levels, making it less than ideal for monitoring CORT circadian rhythms. In the current paper, we examined the applicability of a non-invasive fecal CORT metabolite measure to assess the circadian rhythm. We compared fecal CORT metabolite levels to circulating CORT levels, and analyzed change in the fecal circadian rhythm following an acute stressor (i.e. blood sampling by tail veil catheter). Fecal and blood samples were collected from male adolescent rats and analyzed for CORT metabolites and circulating CORT respectively. Fecal samples were collected hourly for 24 hours pre- and post-blood draw. On average, peak fecal CORT metabolite values occurred 7–9 hours after the plasma CORT peak and time-matched fecal CORT values were well correlated with plasma CORT. As a result of the rapid blood draw, fecal production and CORT levels were altered the next day. These results indicate fecal CORT metabolite measures can be used to assess conditions that disrupt the circadian CORT rhythm, and provide a method to measure long-term changes in CORT production. This can benefit research that requires long-term glucocorticoid assessment (e.g. stress mechanisms underlying health). PMID:18380537

  20. Non-Invasive Techniques for Detection and Diagnosis of Oral Potentially Malignant Disorders.

    PubMed

    Liu, Dongjuan; Zhao, Xin; Zeng, Xin; Dan, Hongxia; Chen, Qianming

    2016-01-01

    Oral squamous cell carcinoma (OSCC) is the most common oral and maxillofacial malignancy, and its morbidity and mortality rates are still high in most countries. Oral potentially malignant disorders (PMDs) are used to refer to a heterogeneous group of conditions that are characterized by increased risk for malignant transformation to OSCC. Currently identified oral PMDs include leukoplakia, erythroplakia, palatal lesions associated with reverse smoking, oral lichen planus, oral submucous fibrosis, actinic keratosis, and discoid lupus erythematosus. The early detection and diagnosis of these lesions are important for cancer prevention and disease management. In recent years, there has been a growing and persistent demand for new non-invasive, practical diagnostic techniques that might facilitate the early detection of oral PMDs. The non-invasive detection techniques evaluated in this review are divided into four categories: vital staining with a solution that can be used as a mouth rinse or applied onto a suspected area of the mouth, light-based detection systems, optical diagnostic technologies that employ returned optical signals to reflect structural and morphological changes within tissues, and salivary biomarkers. Most of these techniques have shown great potential for screening and monitoring oral PMDs. In this review article, the authors critically assess these non-invasive detection techniques for oral PMDs. We also provide a summary of the sensitivity and specificity of each technique in detecting oral PMDs and oral cancer, as well as their advantages, disadvantages, clinical applications, and indications. PMID:26888696

  1. A review of non-invasive imaging methods and applications in contaminant hydrogeology research.

    PubMed

    Werth, Charles J; Zhang, Changyong; Brusseau, Mark L; Oostrom, Mart; Baumann, Thomas

    2010-04-01

    Contaminant hydrogeological processes occurring in porous media are typically not amenable to direct observation. As a result, indirect measurements (e.g., contaminant breakthrough at a fixed location) are often used to infer processes occurring at different scales, locations, or times. To overcome this limitation, non-invasive imaging methods are increasingly being used in contaminant hydrogeology research. Four of the most common methods, and the subjects of this review, are optical imaging using UV or visible light, dual-energy gamma radiation, X-ray microtomography, and magnetic resonance imaging (MRI). Non-invasive imaging techniques have provided valuable insights into a variety of complex systems and processes, including porous media characterization, multiphase fluid distribution, fluid flow, solute transport and mixing, colloidal transport and deposition, and reactions. In this paper we review the theory underlying these methods, applications of these methods to contaminant hydrogeology research, and methods' advantages and disadvantages. As expected, there is no perfect method or tool for non-invasive imaging. However, optical methods generally present the least expensive and easiest options for imaging fluid distribution, solute and fluid flow, colloid transport, and reactions in artificial two-dimensional (2D) porous media. Gamma radiation methods present the best opportunity for characterization of fluid distributions in 2D at the Darcy scale. X-ray methods present the highest resolution and flexibility for three-dimensional (3D) natural porous media characterization, and 3D characterization of fluid distributions in natural porous media. And MRI presents the best option for 3D characterization of fluid distribution, fluid flow, colloid transport, and reaction in artificial porous media. Obvious deficiencies ripe for method development are the ability to image transient processes such as fluid flow and colloid transport in natural porous media in three

  2. A REVIEW OF NON-INVASIVE IMAGING METHODS AND APPLICATIONS IN CONTAMINANT HYDROGEOLOGY RESEARCH

    SciTech Connect

    Werth, Charles J.; Zhang, Changyong; Brusseau, M. L.; Oostrom, Martinus; Baumann, T.

    2010-03-08

    Contaminant hydrogeological processes occurring in porous media are typically not amenable to direct observation. As a result, indirect measurements (e.g., contaminant breakthrough at a fixed location) are often used to infer processes occurring at different scales, locations, or times. To overcome this limitation, non-invasive imaging methods are increasingly being used in contaminant hydrogeology research. The most common methods, and the subjects of this review, are optical imaging using UV or visible light, dual-energy gamma-radiation, X-ray microtomography, and magnetic resonance imaging (MRI). Non-invasive imaging techniques have provided valuable insights into a variety of complex systems and processes, including porous media characterization, multiphase fluid distribution, fluid flow, solute transport and mixing, colloidal transport and deposition, and reactions. In this paper we review the theory underlying these methods, applications of these methods to contaminant hydrogeology research, and methods’ advantages and disadvantages. As expected, there is no perfect method or tool for non-invasive imaging. However, optical methods generally present the least expensive and easiest options for imaging fluid distribution, solute and fluid flow, colloid transport, and reactions in artificial two-dimensional (2D) porous media. Gamma radiation methods present the best opportunity for characterization of fluid distributions in 2D at the Darcy scale. X-ray methods present the highest resolution and flexibility for three-dimensional (3D) natural porous media characterization, and 3D characterization of fluid distributions in natural porous media. And MRI presents the best option for 3D characterization of fluid distribution, fluid flow, colloid transport, and reaction in artificial porous media. Obvious deficiencies ripe for method development are the ability to image transient processes such as fluid flow and colloid transport in natural porous media in three

  3. Novel optical oxy/deoxy hemoglobin monitoring as a modality for non-invasive real-time monitoring of cognitive activity and beyond

    NASA Astrophysics Data System (ADS)

    Davies-Shaw, Dana; Huser, Thomas R.

    2008-02-01

    We report on the successful development of a custom in vitro system that provides a physiologically relevant means of demonstrating optical methodologies for the calibration and validation of oxygen delivery and hemoglobin oxygen binding dynamics in the brain. While measured optical signals have generally been equated to heme absorbance values that are, in turn, presumed to correspond to oxygen delivery, there has been little specific study of the sigmoidal oxygen binding dynamics of hemoglobin, a tetrameric protein, within physiologically relevant parameters. Our development of this novel analytical device addresses this issue, and is a significant step towards the minimally invasive and real-time monitoring of spatially resolved cognitive processes. As such, it is of particular interest for the detection of autistic brain activity in infants and young children. Moreover, our device and approach bring with them the ability to quantify and spatially resolve oxygen delivery down to volumes relevant to individual cell oxygen uptake, without any oxygen consumption, and with a temporal resolution that is physically unachievable by any oxygen tracking modality such as fMRI etc. Such a capability opens up myriad possibilities for further investigation, such as real-time tumor biopsy and resection; the tracking and quantification of cellular proliferation, as well as metabolic measures of tissue viability, to name but a few. Our system has also been engineered to be synergistic with virtually all imaging techniques, optical and otherwise.

  4. Optical Coherence Tomography: its role in the non-invasive structural examination and conservation of cultural heritage objects—a review

    NASA Astrophysics Data System (ADS)

    Targowski, Piotr; Iwanicka, Magdalena

    2012-02-01

    A brief introduction to Optical Coherence Tomography (OCT) is presented, stressing the origin of the tomographic signal and the detection methods defining various modalities of the technique. The parameters of the tomographs, such as axial and lateral resolution, wavelength and intensity of the probing light, imaging range, time of examination, and sensitivity are then defined, and a paradigm for interpreting the OCT tomograms provided. The second part of the article comprises a review of the utilisation of OCT for structural examination of artworks, illustrated with some representative results. Applications to the structural imaging of semi-transparent subsurface layers such as varnishes and glazes, of underdrawings and of reverse painting on glass, are described first, and then applications in the examination of the structure and state of preservation of historic glass, jade, glazed porcelain and faience are discussed. Finally, the use of OCT combined with LIBS analysis and laser ablation of surface layers is presented.

  5. Non-invasive diagnostic methods in dentistry

    NASA Astrophysics Data System (ADS)

    Todea, Carmen

    2016-03-01

    The paper, will present the most important non-invasive methods for diagnostic, in different fields of dentistry. Moreover, the laser-based methods will be emphasis. In orthodontics, 3D laser scanners are increasingly being used to establish database for normative population and cross-sectional growth changes but also to asses clinical outcomes in orthognatic surgical and non-surgical treatments. In prevention the main methods for diagnostic of demineralization and caries detection in early stages are represented by laser fluorescence - Quantitative Light Florescence (QLF); DiagnoDent-system-655nm; FOTI-Fiberoptic transillumination; DIFOTI-Digital Imaging Fiberoptic transillumination; and Optical Coherence Tomography (OCT). In odontology, Laser Doppler Flowmetry (LDF) is a noninvasive real time method used for determining the tooth vitality by monitoring the pulp microcirculation in traumatized teeth, fractured teeth, and teeth undergoing different conservative treatments. In periodontology, recently study shows the ability of LDF to evaluate the health of gingival tissue in periodontal tissue diseases but also after different periodontal treatments.

  6. 3-D spectral IP imaging: Non-invasive characterization of contaminant plumes. Annual progress report, September 15, 1996--September 14, 1997

    SciTech Connect

    Frye, K.M.; Lesmes, D.P.; Morgan, F.D.; Rodi, W.; Shi, W.; Sturrock, J.

    1997-12-01

    'The objective of this project is to develop the scientific basis for characterizing contaminant plumes in the earth''s subsurface using field measurements of induced polarization (IP) effects. The first-year accomplishments are (1) laboratory experiments on fluid-saturated sandstones quantifying the dependence of spectral IP responses on solution chemistry and rock micro-geometry; (2) library research on the current understanding of electromagnetic coupling effects on IP data acquired in the field: and (3) development of prototype forward modeling and inversion algorithms for interpreting IP data in terms of 3-D models of complex resistivity.'

  7. Non-Invasive Neuromodulation for Headache Disorders.

    PubMed

    Zhu, Shuhan; Marmura, Michael J

    2016-02-01

    Migraine and other chronic headache disorders are common and if inadequately treated, can lead to significant disability. The effectiveness of medications can be limited by side effects, drug interactions, and comorbid diseases necessitating alternative methods. Technological developments in the past 5 years have made it possible to use non-invasive methods of neuromodulation to treat primary headache disorders. This field includes technologies such as supraorbital transcutaneous stimulation (STS), transcranial magnetic stimulation (TMS), and non-invasive vagal nerve stimulation (nVNS). Existing trials show these modalities are safe and well tolerated and can be combined with standard pharmacotherapy. We review the technologies, biological rationales, and trials involving non-invasive neuromodulation for the treatment of primary headache disorders. PMID:26750126

  8. Quick recovery and characterization of cell-free DNA in seminal plasma of normozoospermia and azoospermia: implications for non-invasive genetic utilities.

    PubMed

    Li, Hong-Gang; Huang, Shi-Yun; Zhou, Hui; Liao, Ai-Hua; Xiong, Cheng-Liang

    2009-11-01

    We established a quick and reliable method for recovering cell-free seminal DNA (cfsDNA), by using the binding-washing-elution procedure on the DNA purification column. Low variations (below 15%) among the triplicate values of cfsDNA quantity verified the reproducibility of our cfsDNA recovery method. Similar cfsDNA yield and size distribution between seminal plasma acquired by filtration and centrifugation confirmed the presence of cfsDNA. To investigate the general characterization of cfsDNA, the quantitation and size distribution of cfsDNA from normozoospermic and azoospermic semen were analyzed by real-time PCR and electrophoresis, respectively. CfsDNA concentration in semen with normozoospermia (n = 11) was 1.34 +/- 0.65 microg mL(-1), whereas a higher cfsDNA concentration was observed in azoospermia (2.56 +/- 1.43 microg mL(-1), n = 9). The continuous distribution of DNA fragments ranging from approximately 1 kb to 15 kb and a spectrum of multiples of 180-bp fragments were observed in each normozoospermic and azoospermic sample. Distinct characteristic DNA ladder fragmentations in some azoospermic samples implicated that cfsDNA originate partly from apoptotic cells. CfsDNAs of 36 selected azoospermic patients with known information of Y chromosome microdeletion were subjected to the same microdeletion analysis by multiplex PCR and PCR amplification of sY114 (1450 bp). All multiplex PCR reactions with cfsDNA amplified successfully and provided the same result as leukocyte DNA. PCR amplification of sY114 gave a 1450-bp amplicon as expected. Our data suggested the potential use of cfsDNA in search of biomarker or diagnostic procedures. PMID:19823179

  9. Non-invasive Intratracheal Instillation in Mice

    PubMed Central

    Ortiz-Muñoz, Guadalupe; Looney, Mark R.

    2016-01-01

    The intratracheal instillation technique is used to deliver a variety of agents to the lungs ranging from pathogens (bacteria, viruses), toxins, to therapeutic agents. To model lung inflammation and injury, LPS can be administrated via intranasal, intratracheal, or aerosol approaches. Each technique has its limitations. The intratracheal technique can involve the non-invasive instillation method (via the oro-tracheal route) or a direct injection into the trachea. Here, we describe an optimized method for direct visual instillation of LPS via the non-invasive oro-tracheal route.

  10. A review on the non-invasive evaluation of skeletal muscle oxygenation

    NASA Astrophysics Data System (ADS)

    Halim, A. A. A.; Laili, M. H.; Aziz, N. A.; Laili, A. R.; Salikin, M. S.; Rusop, M.

    2016-07-01

    The aim of this review is to conduct a feasibility study of non-invasive evaluation in skeletal muscle oxygenation. This non-invasive evaluation could extract many information using a safe non-invasive method regarding to the oxygenation and microcirculation status in human blood muscle. This brief review highlights the progress of the application of NIRS to evaluate skeletal muscle oxygenation in various activity of human nature from the historical point of view to the present advancement. Since the discovery of non-invasive optical method during 1992, there are many non-invasive techniques uses optical properties on human subject such as near infrared spectroscopy NIRS, optical topography, functional near infrared spectroscopy fNIRS and imaging fNIRI. Furthermore, in this paper we discuss the light absorption potential (LAP) towards chromophores content inside human muscle. Modified beer lambert law was studied in order to build a better understanding toward LAP between chromophores under tissue multilayers in human muscle. This paper will describe the NIRS principle and the basis for its proposed used in skeletal muscle oxygenation. This will cover the advantages and limitation of such application. Thus, these non-invasive techniques could open other possibilities to study muscle performance diagnosis.

  11. Non-invasive monitoring of spreading depression.

    PubMed

    Bastany, Zoya J R; Askari, Shahbaz; Dumont, Guy A; Speckmann, Erwin-Josef; Gorji, Ali

    2016-10-01

    Spreading depression (SD), a slow propagating depolarization wave, plays an important role in pathophysiology of different neurological disorders. Yet, research into SD-related disorders has been hampered by the lack of non-invasive recording techniques of SD. Here we compared the manifestations of SD in continuous non-invasive electroencephalogram (EEG) recordings to invasive electrocorticographic (ECoG) recordings in order to obtain further insights into generator structures and electrogenic mechanisms of surface recording of SD. SD was induced by KCl application and simultaneous SD recordings were performed by scalp EEG as well as ECoG electrodes of somatosensory neocortex of rats using a novel homemade EEG amplifier, AgCl recording electrodes, and high chloride conductive gel. Different methods were used to analyze the data; including the spectrogram, bi-spectrogram, pattern distribution, relative spectrum power, and multivariable Gaussian fit analysis. The negative direct current (DC) shifts recorded by scalp electrodes exhibited a high homogeneity to those recorded by ECoG electrodes. Furthermore, this novel method of recording and analysis was able to separate SD recorded by scalp electrodes from non-neuronal DC shifts induced by other potential generators, such as the skin, muscles, arteries, dura, etc. These data suggest a novel application for continuous non-invasive monitoring of DC potential changes, such as SD. Non-invasive monitoring of SD would allow early intervention and improve outcome in SD-related neurological disorders. PMID:27397413

  12. [Pulmonary non invasive infection by Scedosporium apiospermum].

    PubMed

    Cruz, Rodrigo; Barros, Manuel; Reyes, Mirtha

    2015-08-01

    We reported a case of non-invasive pulmonary infection by Scedosporium apiospermum in 67 years old female with bronchiectasis and caverns secondary to tuberculosis. Diagnosis was made with lung CT and bronchial lavage cultures. The patient was initially treated with itraconazole for six weeks without success and then voriconazole for 16 weeks, with good clinical response. PMID:26436797

  13. Electro-Optical Characterization

    SciTech Connect

    Not Available

    2006-06-01

    In the Electro-Optical Characterization group, within the National Center for Photovoltaic's Measurements and Characterization Division, we use various electrical and optical experimental techniques to relate photovoltaic device performance to the methods and materials used to produce them. The types of information obtained by these techniques range from small-scale atomic-bonding information to large-scale macroscopic quantities such as optical constants and electron-transport properties. Accurate and timely measurement of the electro-optical properties as a function of device processing provides researchers and manufacturers with the knowledge needed to troubleshoot problems and develop the knowledge base necessary for reducing cost, maximizing efficiency, improving reliability, and enhancing manufacturability. We work collaboratively with you to solve materials- and device-related R&D problems. This sheet summarizes our primary techniques and capabilities.

  14. Cellular phone enabled non-invasive tissue classifier.

    PubMed

    Laufer, Shlomi; Rubinsky, Boris

    2009-01-01

    Cellular phone technology is emerging as an important tool in the effort to provide advanced medical care to the majority of the world population currently without access to such care. In this study, we show that non-invasive electrical measurements and the use of classifier software can be combined with cellular phone technology to produce inexpensive tissue characterization. This concept was demonstrated by the use of a Support Vector Machine (SVM) classifier to distinguish through the cellular phone between heart and kidney tissue via the non-invasive multi-frequency electrical measurements acquired around the tissues. After the measurements were performed at a remote site, the raw data were transmitted through the cellular phone to a central computational site and the classifier was applied to the raw data. The results of the tissue analysis were returned to the remote data measurement site. The classifiers correctly determined the tissue type with a specificity of over 90%. When used for the detection of malignant tumors, classifiers can be designed to produce false positives in order to ensure that no tumors will be missed. This mode of operation has applications in remote non-invasive tissue diagnostics in situ in the body, in combination with medical imaging, as well as in remote diagnostics of biopsy samples in vitro. PMID:19365554

  15. Time-resolved diffused optical characterization of key tissue constituents of human bony prominence locations

    NASA Astrophysics Data System (ADS)

    Konugolu Venkata Sekar, Sanathana; Farina, Andrea; Martinenghi, Edoardo; Dalla Mora, Alberto; Taroni, Paola; Pifferi, Antonio; Negredo, Eugènia; Puig, Jordi; Escrig, Roser; Rosales, Quim; Lindner, Claus; Pagliazzi, Marco; Durduran, Turgut

    2015-07-01

    We report a broadband time-resolved characterization of selected bony prominence locations of the human body. A clinical study was performed at six different bony prominence locations of 53 subjects. A portable broadband time-resolved system equipped with pulse drift and distortion compensation strategy was used for absorption and scattering measurements. Key tissue constituents were quantified as a pilot step towards non-invasive optical assessment of bone pathologies.

  16. Non-invasive neuroimaging using near-infrared light

    NASA Technical Reports Server (NTRS)

    Strangman, Gary; Boas, David A.; Sutton, Jeffrey P.

    2002-01-01

    This article reviews diffuse optical brain imaging, a technique that employs near-infrared light to non-invasively probe the brain for changes in parameters relating to brain function. We describe the general methodology, including types of measurements and instrumentation (including the tradeoffs inherent in the various instrument components), and the basic theory required to interpret the recorded data. A brief review of diffuse optical applications is included, with an emphasis on research that has been done with psychiatric populations. Finally, we discuss some practical issues and limitations that are relevant when conducting diffuse optical experiments. We find that, while diffuse optics can provide substantial advantages to the psychiatric researcher relative to the alternative brain imaging methods, the method remains substantially underutilized in this field.

  17. Non-invasive Mapping of Cardiac Arrhythmias.

    PubMed

    Shah, Ashok; Hocini, Meleze; Haissaguerre, Michel; Jaïs, Pierre

    2015-08-01

    Since more than 100 years, 12-lead electrocardiography (ECG) is the standard-of-care tool, which involves measuring electrical potentials from limited sites on the body surface to diagnose cardiac disorder, its possible mechanism, and the likely site of origin. Several decades of research has led to the development of a 252-lead ECG and computed tomography (CT) scan-based three-dimensional electro-imaging modality to non-invasively map abnormal cardiac rhythms including fibrillation. These maps provide guidance towards ablative therapy and thereby help advance the management of complex heart rhythm disorders. Here, we describe the clinical experience obtained using non-invasive technique in mapping the electrical disorder and guide the catheter ablation of atrial arrhythmias (premature atrial beat, atrial tachycardia, atrial fibrillation), ventricular arrhythmias (premature ventricular beats), and ventricular pre-excitation (Wolff-Parkinson-White syndrome). PMID:26072438

  18. [Non-invasive assessment of liver fibrosis].

    PubMed

    Cohen-Ezra, Oranit; Ben-Ari, Ziv

    2015-03-01

    Chronic liver diseases represent a major public health problem, accounting for significant morbidity and mortality worldwide. Prognosis and management of chronic liver diseases depend on the amount of liver fibrosis. Liver biopsy has long remained the gold standard for assessment of liver fibrosis. Liver biopsy is an invasive procedure with associated morbidity, it is rarely the cause for mortality, and has a few limitations. During the past two decades, in an attempt to overcome the limitations of liver biopsy, non-invasive methods for the evaluation of liver fibrosis have been developed, mainly in the field of viral hepatitis. This review will focus on different methods available for non-invasive evaluation of liver fibrosis including a biological approach which quantifies serum levels of biomarkers of fibrosis and physical techniques which measure liver stiffness by transient elastography, ultrasound or magnetic resonance based elastography, their accuracy, advantages and disadvantages. PMID:25962254

  19. Physiology of non-invasive respiratory support.

    PubMed

    Alexiou, Stamatia; Panitch, Howard B

    2016-06-01

    Non-invasive ventilation (NIV) is used in neonates to treat extrathoracic and intrathoracic airway obstruction, parenchymal lung disease and disorders of control of breathing. Avoidance of airway intubation is associated with a reduction in the incidence of chronic lung disease among preterm infants with respiratory distress syndrome. Use of nasal continuous positive airway pressure (nCPAP) may help establish and maintain functional residual capacity (FRC), decrease respiratory work, and improve gas exchange. Other modes of non-invasive ventilation, which include heated humidified high-flow nasal cannula therapy (HHHFNC), nasal intermittent mandatory ventilation (NIMV), non-invasive pressure support ventilation (NI-PSV), and bi-level CPAP (SiPAP™), have also been shown to provide additional benefit in improving breathing patterns, reducing work of breathing, and increasing gas exchange when compared with nCPAP. Newer modes, such as neurally adjusted ventilatory assist (NAVA), hold the promise of improving patient-ventilator synchrony and so might ultimately improve outcomes for preterm infants with respiratory distress. PMID:26923501

  20. [Non-invasive assessment of fatty liver].

    PubMed

    Egresi, Anna; Lengyel, Gabriella; Hagymási, Krisztina

    2015-04-01

    As the result of various harmful effects (infectious agents, metabolic diseases, unhealthy diet, obesity, toxic agents, autoimmune processes) hepatic damage may develop, which can progress towards liver steatosis, and fibrosis as well. The most common etiological factors of liver damages are hepatitis B and C infection, alcohol consumption and non-alcoholic fatty liver disease. Liver biopsy is considered as the gold standard for the diagnosis of chronic liver diseases. Due to the dangers and complications of liver biopsy, studies are focused on non-invasive markers and radiological imaging for liver steatosis, progression of fatty liver, activity of the necroinflammation and the severity of the fibrosis. Authors review the possibilities of non-invasive assessment of liver steatosis. The statistical features of the probes (positive, negative predictive values, sensitivity, specificity) are reviewed. The role of radiological imaging is also discussed. Although the non-invasive methods discussed in this article are useful to assess liver steatosis, further studies are needed to validate to follow progression of the diseases and to control therapeutic response. PMID:25819147

  1. Optical Characterization Laboratory (Fact Sheet)

    SciTech Connect

    Not Available

    2011-10-01

    This fact sheet describes the purpose, lab specifications, applications scenarios, and information on how to partner with NREL's Optical Characterization Laboratory at the Energy Systems Integration Facility. The Optical Characterization Laboratory at NREL's Energy Systems Integration Facility (ESIF) conducts optical characterization of large solar concentration devices. Concentration solar power (CSP) mirror panels and concentrating solar systems are tested with an emphasis is on measurement of parabolic trough mirror panels. The Optical Characterization Laboratory provides state-of-the-art characterization and testing capabilities for assessing the optical surface quality and optical performance for various CSP technologies including parabolic troughs, linear Fresnel, dishes, and heliostats.

  2. Instrumentation for Non-Invasive Assessment of Cardiovascular Regulation

    NASA Technical Reports Server (NTRS)

    Cohen, Richard J.

    1999-01-01

    It is critically important to be able to assess alterations in cardiovascular regulation during and after space flight. We propose to develop an instrument for the non-invasive assessment of such alterations that can be used on the ground and potentially during space flight. This instrumentation would be used by the Cardiovascular Alterations Team at multiple sites for the study of the effects of space flight on the cardiovascular system and the evaluation of countermeasures. In particular, the Cardiovascular Alterations Team will use this instrumentation in conjunction with ground-based human bed-rest studies and during application of acute stresses e.g., tilt, lower body negative pressure, and exercise. In future studies, the Cardiovascular Alterations Team anticipates using this instrumentation to study astronauts before and after space flight and ultimately, during space flight. The instrumentation may also be used by the Bone Demineralization/Calcium Metabolism Team, the Neurovestibular Team and the Human Performance Factors, Sleep and Chronobiology Team to measure changes in autonomic nervous function. The instrumentation will be based on a powerful new technology - cardiovascular system identification (CSI) - which has been developed in our laboratory. CSI provides a non-invasive approach for the study of alterations in cardiovascular regulation. This approach involves the analysis of second-to-second fluctuations in physiologic signals such as heart rate and non-invasively measured arterial blood pressure in order to characterize quantitatively the physiologic mechanisms responsible for the couplings between these signals. Through the characterization of multiple physiologic mechanisms, CSI provides a closed-loop model of the cardiovascular regulatory state in an individual subject.

  3. In situ non-invasive investigation on the painting techniques of early Meissen Stoneware

    NASA Astrophysics Data System (ADS)

    Miliani, Costanza; Doherty, Brenda; Daveri, Alessia; Loesch, Anette; Ulbricht, Heike; Brunetti, Brunetto G.; Sgamellotti, Antonio

    2009-08-01

    In situ, non-invasive investigations by means of portable X-ray fluorescence and fibre optic reflectance mid-infrared (mid-FTIR) spectroscopy of painted Böttger Stoneware objects have been carried out through the MOLAB transnational access to the Porcelain Collection of the Staatliche Kunstsammlungen in Dresden. It has been possible to gather information regarding the composition of the black glaze by applying a principal component analysis to the elemental analysis to distinguish between the variations of lead, iron and manganese compositions of each glaze. It has been furthermore feasible to combine molecular spectroscopy for characterization of the constituent painting materials, namely lead white as cerusite and hydrocerusite, the use of cinnabar, azurite and Prussian blue leading to a better knowledge of the state of conservation and utility of certain pigments that may give rise to chronology of the decorative artwork. The identification of oxalates namely whedellite and moolooite are assigned as degradation products relative to the decorative areas.

  4. [Non invasive ventilation in the emergency setting].

    PubMed

    Wilhelm, Laetitia; Della Santa, Vincent; Hanhart, Walter-Alexandre

    2015-08-12

    Before the development of non invasive ventilation (NIV), endotracheal intubation was the only ventilatory therapy available in case of severe respiratory distress and acute respiratory failure. NIV used to be employed in intensive care settings only. Nowadays, the use of NIV has been democratized to include the emergency room, and the pre-hospital care setting for treatment of acute respiratory failure. Cardiogenic pulmonary edema and acute exacerbation of COPD are indications of choice, since NIV improves mortality. The efficiency of the therapy depends on early treatment; however, endotracheal intubation should not be delayed when it becomes necessary. PMID:26449102

  5. Using a non-invasive technique in nutrition: synchrotron radiation infrared microspectroscopy spectroscopic characterization of oil seeds treated with different processing conditions on molecular spectral factors influencing nutrient delivery.

    PubMed

    Zhang, Xuewei; Yu, Peiqiang

    2014-07-01

    Non-invasive techniques are a key to study nutrition and structure interaction. Fourier transform infrared microspectroscopy coupled with a synchrotron radiation source (SR-IMS) is a rapid, non-invasive, and non-destructive bioanalytical technique. To understand internal structure changes in relation to nutrient availability in oil seed processing is vital to find optimal processing conditions. The objective of this study was to use a synchrotron-based bioanalytical technique SR-IMS as a non-invasive and non-destructive tool to study the effects of heat-processing methods and oil seed canola type on modeled protein structure based on spectral data within intact tissue that were randomly selected and quantify the relationship between the modeled protein structure and protein nutrient supply to ruminants. The results showed that the moisture heat-related processing significantly changed (p<0.05) modeled protein structures compared to the raw canola (control) and those processing by dry heating. The moisture heating increased (p<0.05) spectral intensities of amide I, amide II, α-helices, and β-sheets but decreased (p<0.05) the ratio of modeled α-helices to β-sheet spectral intensity. There was no difference (p>0.05) in the protein spectral profile between the raw and dry-heated canola tissue and between yellow- and brown-type canola tissue. The results indicated that different heat processing methods have different impacts on the protein inherent structure. The protein intrinsic structure in canola seed tissue was more sensitive and more response to the moisture heating in comparison to the dry heating. These changes are expected to be related to the nutritive value. However, the current study is based on limited samples, and more large-scale studies are needed to confirm our findings. PMID:24920208

  6. Non-invasive glucose determination in the human eye

    NASA Astrophysics Data System (ADS)

    Schrader, Wolfgang; Meuer, Petra; Popp, Jürgen; Kiefer, Wolfgang; Menzebach, Johannes-Ulrich; Schrader, Bernhard

    2005-02-01

    For non-invasive in vivo glucose determinations by means of near-infrared spectroscopy, the anterior chamber of the human eye is a promising site. An optical set-up for the non-invasive glucose determination in the human eye precisely in the anterior chamber with a beam reflected from the surface of the eye lens is presented here. As the anterior chamber has a depth of 3.13±0.50 mm, the beam follows an optical path of 5.3-7.3 mm depending on the angle of incidence, which is individually constant. We will show that it is possible to acquire good concentration predictions for physiological glucose concentrations with such a long optical path. A chemometric study of NIR glucose spectra with concentrations of glucose in water of 10-350 mg/dL (0.56-1.94 mmol/L) resulted in a calibration model which was able to predict physiological glucose concentrations with a root mean square error of prediction RMSEPTest=15.41 mg/dL. The Clarke error grid diagram shows that the model performs well according to medical impact. Using a first in vivo set-up, the precision is not sufficient for a reliable prediction of glucose concentration, especially due to the flickering of the patient's eye and the low reflectivity of the eye lens. Therefore, we have designed a new in vivo set-up: a prototype for a self-monitoring device with controlled geometry and laser radiation at several distinct wavelengths instead of the halogen lamp as light source. This allows a far higher signal/noise ratio under much better reproducible geometrical conditions and at the same time a much smaller necessary light flux.

  7. Measurements and characterization - Electro-optical characterization

    SciTech Connect

    Cook, G.

    2000-03-16

    This brochure presents the capabilities that the Measurements and Characterization Division has in Electro-Optical Characterization, in which a variety of spectroscopy, ellipsometry, and capacitance techniques are used to probe the fundamental electrical and optical properties of solid-state materials.

  8. Non-Invasive Imaging of Vascular Inflammation

    PubMed Central

    Ammirati, Enrico; Moroni, Francesco; Pedrotti, Patrizia; Scotti, Isabella; Magnoni, Marco; Bozzolo, Enrica P.; Rimoldi, Ornella E.; Camici, Paolo G.

    2014-01-01

    In large-vessel vasculitides, inflammatory infiltrates may cause thickening of the involved arterial vessel wall leading to progressive stenosis and occlusion. Dilatation, aneurysm formation, and thrombosis may also ensue. Activated macrophages and T lymphocytes are fundamental elements in vascular inflammation. The amount and density of the inflammatory infiltrate is directly linked to local disease activity. Additionally, patients with autoimmune disorders have an increased cardiovascular (CV) risk compared with age-matched healthy individuals as a consequence of accelerated atherosclerosis. Molecular imaging techniques targeting activated macrophages, neovascularization, or increased cellular metabolic activity can represent effective means of non-invasive detection of vascular inflammation. In the present review, novel non-invasive imaging tools that have been successfully tested in humans will be presented. These include contrast-enhanced ultrasonography, which allows detection of neovessels within the wall of inflamed arteries; contrast-enhanced CV magnetic resonance that can detect increased thickness of the arterial wall, usually associated with edema, or mural enhancement using T2 and post-contrast T1-weighted sequences, respectively; and positron emission tomography associated with radio-tracers such as [18F]-fluorodeoxyglucose and the new [11C]-PK11195 in combination with computed tomography angiography to detect activated macrophages within the vessel wall. Imaging techniques are useful in the diagnostic work-up of large- and medium-vessel vasculitides, to monitor disease activity and the response to treatments. Finally, molecular imaging targets can provide new clues about the pathogenesis and evolution of immune-mediated disorders involving arterial vessels. PMID:25183963

  9. Hybrid CARS for Non-Invasive Blood Glucose Monitoring

    NASA Astrophysics Data System (ADS)

    Wang, Xi; Pestov, Dmitry; Zhang, Aihua; Murawski, Robert; Sokolov, Alexei; Welch, George; Laane, Jaan; Scully, Marlan

    2007-10-01

    We develop a spectroscopy technique that combines the advantages of both the frequency-resolved coherent anti-Stokes Raman scattering (CARS) and the time-resolved CARS. We use broadband preparation pulses to get an instantaneous coherent excitation of multiplex molecular vibration levels and subsequent optically shaped time-delayed narrowband probing pulse to detect these vibrations. This technique can suppress the nonresonant background and retrieve the molecular fingerprint signal efficiently and rapidly. We employ this technique to glucose detection, the final goal of which is accurate, non-invasive (i.e. painless) and continuous monitoring of blood glucose concentration in the Diabetes diagnosis to replace the current glucose measurement process, which requires painful fingerpricks and therefore cannot be performed more than a few times a day. We have gotten the CARS spectra of glucose aqueous solution down to 2 mM.

  10. In vivo non-invasive multiphoton tomography of human skin

    NASA Astrophysics Data System (ADS)

    König, Karsten; Riemann, Iris; Ehlers, Alexander; Le Harzic, Ronan

    2005-10-01

    High resolution non-invasive 3D imaging devices are required to detect pathogenic microorganisms such as Anthrax spores, bacteria, viruses, fungi and chemical agents entering biological tissues such as the epidermis. Due to the low light penetration depth and the biodamage potential, ultraviolet light sources can not be employed to realize intratissue imaging of bio- and chemohazards. We report on the novel near infrared laser technology multiphoton tomography and the high resolution 4D imaging tool DermaInspect for non-invasive detection of intratissue agents and their influence on cellular metabolism based on multiphoton autofluorescence imaging (MAI) and second harmonic generation (SHG). Femtosecond laser pulses in the spectral range of 750 nm to 850 nm have been used to image in vivo human skin with subcellular spatial and picosecond temporal resolution. The non-linear induced autofluorescence of both, skin tissues and microorganisms, originates mainly from naturally endogenous fluorophores/protein structures like NAD(P)H, flavins, keratin, collagen, elastin, porphyrins and melanin. Bacteria emit in the blue/green spectral range due to NAD(P)H and flavoproteins and, in certain cases, in the red spectral range due to the biosynthesis of Zn-porphyrins, coproporphyrin and protoporphyrin. Collagen and exogenous non-centrosymmetric molecules can be detected by SHG signals. The system DermaInspect consists of a wavelength-tunable compact 80/90 MHz Ti:sapphire laser, a scan module with galvo scan mirrors, piezo-driven objective, fast photon detector and time-resolved single photon counting unit. It can be used to perform optical sectioning and 3D autofluorescence lifetime imaging (τ-mapping) with 1 μm spatial resolution and 270 ps temporal resolution. The parameter fluorescence lifetime depends on the type of fluorophore and its microenvironment and can be used to distinguish bio- and chemohazards from cellular background and to gain information for pathogen

  11. Imaging human brain networks to improve the clinical efficacy of non-invasive brain stimulation.

    PubMed

    Sale, Martin V; Mattingley, Jason B; Zalesky, Andrew; Cocchi, Luca

    2015-10-01

    The flexible integration of segregated neural processes is essential to healthy brain function. Advances in neuroimaging techniques have revealed that psychiatric and neurological disorders are characterized by anomalies in the dynamic integration of widespread neural populations. Re-establishing optimal neural activity is an important component of the treatment of such disorders. Non-invasive brain stimulation is emerging as a viable tool to selectively restore both local and widespread neural activity in patients affected by psychiatric and neurological disorders. Importantly, the different forms of non-invasive brain stimulation affect neural activity in distinct ways, which has important ramifications for their clinical efficacy. In this review, we discuss how non-invasive brain stimulation techniques influence widespread neural integration across brain regions. We suggest that the efficacy of such techniques in the treatment of psychiatric and neurological conditions is contingent on applying the appropriate stimulation paradigm to restore specific aspects of altered neural integration. PMID:26409343

  12. Marine Optical Characterizations

    NASA Technical Reports Server (NTRS)

    Clark, Dennis K.

    1996-01-01

    The team's major emphasis during this reporting period has been focused on the completion of the operational versions of the Marine Optical Buoys (MOBY's). Other work areas consisted of designing and testing bio-optical instrumentation, evaluating several of the SeaWiFS bio-optical protocols, processing data collected during field experiments, and reprocessing several of the Marine Optical Characteristics Experiment (MOCE) 2 and 3 bio-optical data sets. The team conducted one trip to the operations site in Honolulu, Hawaii, making necessary preparations for future field experiments. Part of the team also traveled to Moss Landing Marine Laboratories, Salinas, CA, and to American Holographic Co. Fitchburg MA, to assist with the fabrication of the next generation Marine Optical Buoys. Technical memoranda are being written to address the remote sensing reflectance, and instrument self-shading protocols. During the Ocean Color 96 meeting discussions with the Spanish on acquiring research vessel support during the MODIS validation period were conducted. A proposal will be generated towards this purpose for an experiment to be conducted off the North African coast during the summer of 1999.

  13. The roadmap for estimation of cell-type-specific neuronal activity from non-invasive measurements.

    PubMed

    Uhlirova, Hana; Kılıç, Kıvılcım; Tian, Peifang; Sakadžić, Sava; Gagnon, Louis; Thunemann, Martin; Desjardins, Michèle; Saisan, Payam A; Nizar, Krystal; Yaseen, Mohammad A; Hagler, Donald J; Vandenberghe, Matthieu; Djurovic, Srdjan; Andreassen, Ole A; Silva, Gabriel A; Masliah, Eliezer; Kleinfeld, David; Vinogradov, Sergei; Buxton, Richard B; Einevoll, Gaute T; Boas, David A; Dale, Anders M; Devor, Anna

    2016-10-01

    The computational properties of the human brain arise from an intricate interplay between billions of neurons connected in complex networks. However, our ability to study these networks in healthy human brain is limited by the necessity to use non-invasive technologies. This is in contrast to animal models where a rich, detailed view of cellular-level brain function with cell-type-specific molecular identity has become available due to recent advances in microscopic optical imaging and genetics. Thus, a central challenge facing neuroscience today is leveraging these mechanistic insights from animal studies to accurately draw physiological inferences from non-invasive signals in humans. On the essential path towards this goal is the development of a detailed 'bottom-up' forward model bridging neuronal activity at the level of cell-type-specific populations to non-invasive imaging signals. The general idea is that specific neuronal cell types have identifiable signatures in the way they drive changes in cerebral blood flow, cerebral metabolic rate of O2 (measurable with quantitative functional Magnetic Resonance Imaging), and electrical currents/potentials (measurable with magneto/electroencephalography). This forward model would then provide the 'ground truth' for the development of new tools for tackling the inverse problem-estimation of neuronal activity from multimodal non-invasive imaging data.This article is part of the themed issue 'Interpreting BOLD: a dialogue between cognitive and cellular neuroscience'. PMID:27574309

  14. Non invasive monitoring in mechanically ventilated pediatric patients.

    PubMed

    Al-Subu, Awni M; Rehder, Kyle J; Cheifetz, Ira M; Turner, David A

    2014-12-01

    Cardiopulmonary monitoring is a key component in the evaluation and management of critically ill patients. Clinicians typically rely on a combination of invasive and non-invasive monitoring to assess cardiac output and adequacy of ventilation. Recent technological advances have led to the introduction: of continuous non-invasive monitors that allow for data to be obtained at the bedside of critically ill patients. These advances help to identify hemodynamic changes and allow for interventions before complications occur. In this manuscript, we highlight several important methods of non-invasive cardiopulmonary monitoring, including capnography, transcutaneous monitoring, pulse oximetry, and near infrared spectroscopy. PMID:25119483

  15. Non-invasive experimental determination of a CT source model.

    PubMed

    Alikhani, Babak; Büermann, Ludwig

    2016-01-01

    Non-invasive methods to determine equivalent X-ray source models of a CT scanner are presented. A high-precision technique called TRIC ("Time Resolved Integrated Charge") was developed and used to characterize the bow tie filters (BT) of the CT scanner installed at Physikalisch-Technische Bundesanstalt (PTB). Aluminum (Al) and polymethyl methacrylate (PMMA) equivalent thicknesses of the BT filters at all tube high voltages were evaluated, assuming that those consist of only one material. Thereby two different dose probes were used, a solid state detector and an ionization chamber, the former characterized by a significant and the latter by an almost negligible energy dependence of the air kerma response. A method was developed to correct for the energy dependence of the solid state dose probe. Next, a two-component material was assumed and equivalent BT filters were evaluated. The latter method was also applied using the known real BT filter materials and compared with the shape of the real BT filters. Finally, the results obtained by the TRIC method were compared with those obtained by using the so-called COBRA method ("Characterization Of Bow tie Relative Attenuation"), the latter being more suitable for measurements in a clinical environment. PMID:26602858

  16. Optic probe for semiconductor characterization

    DOEpatents

    Sopori, Bhushan L.; Hambarian, Artak

    2008-09-02

    Described herein is an optical probe (120) for use in characterizing surface defects in wafers, such as semiconductor wafers. The optical probe (120) detects laser light reflected from the surface (124) of the wafer (106) within various ranges of angles. Characteristics of defects in the surface (124) of the wafer (106) are determined based on the amount of reflected laser light detected in each of the ranges of angles. Additionally, a wafer characterization system (100) is described that includes the described optical probe (120).

  17. Test target for characterizing 3D resolution of optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Hu, Zhixiong; Hao, Bingtao; Liu, Wenli; Hong, Baoyu; Li, Jiao

    2014-12-01

    Optical coherence tomography (OCT) is a non-invasive 3D imaging technology which has been applied or investigated in many diagnostic fields including ophthalmology, dermatology, dentistry, cardiovasology, endoscopy, brain imaging and so on. Optical resolution is an important characteristic that can describe the quality and utility of an image acquiring system. We employ 3D printing technology to design and fabricate a test target for characterizing 3D resolution of optical coherence tomography. The test target which mimics USAF 1951 test chart was produced with photopolymer. By measuring the 3D test target, axial resolution as well as lateral resolution of a spectral domain OCT system was evaluated. For comparison, conventional microscope and surface profiler were employed to characterize the 3D test targets. The results demonstrate that the 3D resolution test targets have the potential of qualitatively and quantitatively validating the performance of OCT systems.

  18. Improving non-invasive ventilation documentation.

    PubMed

    Smith, Matthew; Elkheir, Natalie

    2014-01-01

    Record keeping for patients on non-invasive ventilation (NIV) at St. Georges Hospital is poor. The initial NIV prescription is often not recorded, and changes to the NIV prescription or the rationale for the changes (ABG results) are also poorly documented. This leads to confusion for nurses/doctors as to what the correct settings are, meaning patients could receive ineffective ventilation. The use of NIV is also poorly recorded by nursing staff meaning that doctors are unsure if the prescribed NIV is being achieved. This can lead to treatment being escalated unnecessarily in the event of treatment failure. Non-invasive ventilation (NIV) is the provision of ventilatory support in the form of positive pressure via the patient's upper airway using a mask or similar device. NIV is indicated for treatment of acute hypercapnic respiratory failure, of which there are many causes, though COPD is the indication in up to 70% of cases.[1] British Thoracic Society (BTS) guidelines for NIV suggest that the rationale for commencing a patient on NIV and the proposed settings should be clearly documented.[2] Clinicians cannot effectively tailor changes to the patients NIV settings if this information is not clearly recorded, which could lead to increased time requiring NIV or NIV failure. Three main areas were considered important to measure for this project. The initial prescription of the NIV, changes to the NIV settings, and nursing documentation surrounding NIV. A baseline measurement of NIV documentation for two weeks found NIV documentation to globally very poor. NIV was formally prescribed 29% of the time, full detail of intended settings were documented 57% of the time, the decision to commence NIV was discussed with the respiratory consultant/SpR just 29% of the time and on no occasion was a decision regarding escalation of treatment recorded. Eighteen changes were made to the NIV settings. These were formally prescribed 22% of the time and detail of the intended

  19. Modern non-invasive mechanical ventilation turns 25.

    PubMed

    Díaz Lobato, Salvador; Mayoralas Alises, Sagrario

    2013-11-01

    The history of non-invasive mechanical ventilation goes back more than 100 years, but it was not until 1987 when what we could call "modern" non-invasive mechanical ventilation was developed. The description of Delaubier and Rideau of a patient with Duchenne's disease who had been effectively ventilated through a nasal mask marked the start of a new era in the history of non-invasive mechanical ventilation. Over these last 25years, we have witnessed exponential growth in its use, field of activity and technological advances on an exciting fast-paced track. We believe that it is time to review the main milestones that have marked the development of non-invasive mechanical ventilation to date, while paying homage to this therapeutic method that has contributed so much to the advancement of respiratory medicine in the last 25years. PMID:23347549

  20. A computer controlled non-invasive haemodynamic monitoring system.

    PubMed

    McMenemin, I M; Kenny, G N

    1988-10-01

    A system for the non-invasive monitoring, recording and storing haemodynamic indices has been developed using an Apple II microcomputer, a Dinamap automatic arterial pressure monitor and a non-invasive cardiac output monitor based on bio-electrical impedance. This system was used during the induction and maintenance of anaesthesia. Numerical and graphical displays of heart rate, arterial pressure, cardiac output and systemic vascular resistance are available. A print-out of data can be produced for later analysis. PMID:3190976

  1. Non-invasive biosensor and wilreless interrogating system for hypoglycemia

    NASA Astrophysics Data System (ADS)

    Varadan, Vijay K.; Whitchurch, Ashwin K.; Saukesi, K.

    2002-11-01

    Hypoglycemia - abnormal decrease in blood sugar - is a major obstacle in the management of diabetes and prevention of long-term complications, and it may impose serious effects on the brain, including impairment of memory and other cognitive functions. This paper presents the development of a non-invasive sensor with miniaturized telemetry device in a wrist-watch for monitoring glucose concentration in blood. The sensor concept is based on optical chiralit of glucose level in the interstitial fluid. The wrist watch consists of a laser power source of the wavelength compatible with the glucose. A nanofilm with specific chirality is placed at the bottom of the watch. The light then passes through the film and illuminates a small area on the skin.It has been documented that there is certain concentration of sugar level is taken by the intertitial fluid from the blood stream and deposit a portion of it at the dead skin. The wrist-watch when in contact with the outer skin of the human will thus monitor the glucose concentration. A wireless monitoring system in the watch then downloads the data from the watch to a Palm or laptop computer.

  2. A Novel Long-term, Multi-Channel and Non-invasive Electrophysiology Platform for Zebrafish.

    PubMed

    Hong, SoonGweon; Lee, Philip; Baraban, Scott C; Lee, Luke P

    2016-01-01

    Zebrafish are a popular vertebrate model for human neurological disorders and drug discovery. Although fecundity, breeding convenience, genetic homology and optical transparency have been key advantages, laborious and invasive procedures are required for electrophysiological studies. Using an electrode-integrated microfluidic system, here we demonstrate a novel multichannel electrophysiology unit to record multiple zebrafish. This platform allows spontaneous alignment of zebrafish and maintains, over days, close contact between head and multiple surface electrodes, enabling non-invasive long-term electroencephalographic recording. First, we demonstrate that electrographic seizure events, induced by pentylenetetrazole, can be reliably distinguished from eye or tail movement artifacts, and quantifiably identified with our unique algorithm. Second, we show long-term monitoring during epileptogenic progression in a scn1lab mutant recapitulating human Dravet syndrome. Third, we provide an example of cross-over pharmacology antiepileptic drug testing. Such promising features of this integrated microfluidic platform will greatly facilitate high-throughput drug screening and electrophysiological characterization of epileptic zebrafish. PMID:27305978

  3. A Novel Long-term, Multi-Channel and Non-invasive Electrophysiology Platform for Zebrafish

    PubMed Central

    Hong, SoonGweon; Lee, Philip; Baraban, Scott C.; Lee, Luke P.

    2016-01-01

    Zebrafish are a popular vertebrate model for human neurological disorders and drug discovery. Although fecundity, breeding convenience, genetic homology and optical transparency have been key advantages, laborious and invasive procedures are required for electrophysiological studies. Using an electrode-integrated microfluidic system, here we demonstrate a novel multichannel electrophysiology unit to record multiple zebrafish. This platform allows spontaneous alignment of zebrafish and maintains, over days, close contact between head and multiple surface electrodes, enabling non-invasive long-term electroencephalographic recording. First, we demonstrate that electrographic seizure events, induced by pentylenetetrazole, can be reliably distinguished from eye or tail movement artifacts, and quantifiably identified with our unique algorithm. Second, we show long-term monitoring during epileptogenic progression in a scn1lab mutant recapitulating human Dravet syndrome. Third, we provide an example of cross-over pharmacology antiepileptic drug testing. Such promising features of this integrated microfluidic platform will greatly facilitate high-throughput drug screening and electrophysiological characterization of epileptic zebrafish. PMID:27305978

  4. Marine optical characterizations

    NASA Technical Reports Server (NTRS)

    Clark, Dennis K.; Ge, Yuntao; Hovey, Phil; King, ED; Stengel, Eric; Yuen, Marilyn; Koval, Larisa

    1995-01-01

    During the past three months, the MOCE Team conducted two field experiments in Mill Creek,Chesapeake Bay, from July 24 to August 4, and at the MOBY operations site at Snug Harbor, Honolulu, Hawaii, from August 15-30, prepared two technical memoranda, and continued MOCE-2 and MOCE-3 data reduction. The primary purposes of the experiments were to test the SeaWiFS 'remote sensing reflectance' protocol, obtain turbid water data for ocean color satellite algorithm development, perform calibration for both Near Infrared (NIR) and Visible Rainbow Spectrometer system, continue assembling the operational Marine Optical Buoy, and to test the MOBY cellular phone communications link at the Lanai mooring site.

  5. Non invasive tools for the diagnosis of liver cirrhosis

    PubMed Central

    Soresi, Maurizio; Giannitrapani, Lydia; Cervello, Melchiorre; Licata, Anna; Montalto, Giuseppe

    2014-01-01

    Liver cirrhosis (LC), the end stage of many forms of chronic hepatitis of different etiologies is a diffuse process characterized by fibrosis and the conversion of normal liver architecture into structurally abnormal nodules surrounded by annular fibrosis. This chronic progressive clinical condition, leads to liver cell failure and portal hypertension, which can favour the onset of hepatocellular carcinoma. Defining the phase of the natural history is crucial for therapeutic choice and prognosis. Liver biopsy is currently considered the best available standard of reference but it has some limits, so alternative tools have been developed to substitute liver biopsy when assessing liver fibrosis. Serum markers offer a cost-effective alternative to liver biopsy being less invasive and theoretically without complications. They can be classified into direct and indirect markers which may be used alone or in combination to produce composite scores. Diagnostic imaging includes a number of instruments and techniques to estimate liver fibrosis and cirrhosis like ultrasound (US), US Doppler, contrast enhanced US and Elastography. US could be used for the diagnosis of advanced LC while is not able to evaluate progression of fibrosis, in this case Elastography is more reliable. This review aims to revise the most recent data from the literature about non invasive methods useful in defining liver fibrosis. PMID:25561782

  6. Optical characterization of isotactic polypropylene and carbon nanotube composites using spectroscopic ellipsometry

    NASA Astrophysics Data System (ADS)

    Sarkar, Sabyasachi; Kalakonda, Parvathalu; Georgiev, Georgi; Iannacchione, Germano

    2013-03-01

    We report the dielectric properties of optically characterized isotactic polypropylene (iPP) and its composites with carbon nanotubes (CNTs) using spectroscopic ellipsometry. Characterization was performed at angles ranging from 50 to 70 degrees and for the spectral range between 300-1000 nm. CNT concentrations varied from 0 to 5 wt% in the iPP/CNT composites investigated. Ellipsometry is a non-invasive and non-destructive technique that enabled us to determine the dielectric properties of the materials investigated. A concentration dependency on CNT wt% was found to exist for both the refractive index and the extinction coefficient for the iPP/CNT composites. At higher concentrations however, this distinction was not very clear, suggesting that saturation levels were reached in the material. We will also discuss our efforts to separate the optical properties of bound CNT from the analyzed nanocomposites.

  7. Optical characterization of frame grabbers

    NASA Astrophysics Data System (ADS)

    Pozo, A. M.; Rubiño, M.

    2013-04-01

    Today, video cameras connected to frame grabbers are used in many applications such as traffic control, surveillance, medical systems or machine vision. In this work, we present an optical characterization of frame grabbers in terms of their spatial-frequency responses. This characterization is based on the modulation transfer function (MTF) determination from speckle patterns using a low-cost experimental setup. We have characterized and compared three different frame grabbers. The three frame grabbers produce an amplification (boost) in the horizontal MTF in different spatial-frequency ranges and having different maximum amplification values.

  8. Optical Characterization of Biological Tissues

    NASA Astrophysics Data System (ADS)

    Barrera, Frederick; Sardar, Dhiraj; Tsin, Andrew

    2008-03-01

    University of Texas at San Antonio, San Antonio, Texas 78249. An in-depth characterization of optical properties of biological tissues has been performed. The wavelength-dependent total diffuse reflection (Rd) and total transmission (Tt) measurements have been taken for individual tissue by using a double-integrating sphere setup. The index of refraction of the tissue will be determined using conventional optical techniques. The Inverse Adding Doubling (IAD) computational method is applied to the measured values of n, Rd, and Tt to calculate the optical absorption and scattering coefficients as well as the scattering anisotropy coefficients of these tissues. The Rd and Tt determined by the IAD method were compared with those generated by the Monte Carlo simulation technique. A thorough comparison of the scattering characteristics of these tissues has been made. Furthermore, a comparison of these optical scattering and absorption coefficients calculated by IAD method were compared to the values determined by the Kubelka-Munk model.

  9. Autoimmune pancreatitis: Multimodality non-invasive imaging diagnosis.

    PubMed

    Crosara, Stefano; D'Onofrio, Mirko; De Robertis, Riccardo; Demozzi, Emanuele; Canestrini, Stefano; Zamboni, Giulia; Pozzi Mucelli, Roberto

    2014-12-01

    Autoimmune pancreatitis (AIP) is characterized by obstructive jaundice, a dramatic clinical response to steroids and pathologically by a lymphoplasmacytic infiltrate, with or without a pancreatic mass. Type 1 AIP is the pancreatic manifestation of an IgG4-related systemic disease and is characterized by elevated IgG4 serum levels, infiltration of IgG4-positive plasma cells and extrapancreatic lesions. Type 2 AIP usually has none or very few IgG4-positive plasma cells, no serum IgG4 elevation and appears to be a pancreas-specific disorder without extrapancreatic involvement. AIP is diagnosed in approximately 2%-6% of patients that undergo pancreatic resection for suspected pancreatic cancer. There are three patterns of autoimmune pancreatitis: diffuse disease is the most common type, with a diffuse, "sausage-like" pancreatic enlargement with sharp margins and loss of the lobular contours; focal disease is less common and manifests as a focal mass, often within the pancreatic head, mimicking a pancreatic malignancy. Multifocal involvement can also occur. In this paper we describe the features of AIP at ultrasonography, computed tomography, magnetic resonance and positron emission tomography/computed tomography imaging, focusing on diagnosis and differential diagnosis with pancreatic ductal adenocarcinoma. It is of utmost importance to make an early correct differential diagnosis between these two diseases in order to identify the optimal therapeutic strategy and to avoid unnecessary laparotomy or pancreatic resection in AIP patients. Non-invasive imaging plays also an important role in therapy monitoring, in follow-up and in early identification of disease recurrence. PMID:25493001

  10. Autoimmune pancreatitis: Multimodality non-invasive imaging diagnosis

    PubMed Central

    Crosara, Stefano; D'Onofrio, Mirko; De Robertis, Riccardo; Demozzi, Emanuele; Canestrini, Stefano; Zamboni, Giulia; Pozzi Mucelli, Roberto

    2014-01-01

    Autoimmune pancreatitis (AIP) is characterized by obstructive jaundice, a dramatic clinical response to steroids and pathologically by a lymphoplasmacytic infiltrate, with or without a pancreatic mass. Type 1 AIP is the pancreatic manifestation of an IgG4-related systemic disease and is characterized by elevated IgG4 serum levels, infiltration of IgG4-positive plasma cells and extrapancreatic lesions. Type 2 AIP usually has none or very few IgG4-positive plasma cells, no serum IgG4 elevation and appears to be a pancreas-specific disorder without extrapancreatic involvement. AIP is diagnosed in approximately 2%-6% of patients that undergo pancreatic resection for suspected pancreatic cancer. There are three patterns of autoimmune pancreatitis: diffuse disease is the most common type, with a diffuse, “sausage-like” pancreatic enlargement with sharp margins and loss of the lobular contours; focal disease is less common and manifests as a focal mass, often within the pancreatic head, mimicking a pancreatic malignancy. Multifocal involvement can also occur. In this paper we describe the features of AIP at ultrasonography, computed tomography, magnetic resonance and positron emission tomography/computed tomography imaging, focusing on diagnosis and differential diagnosis with pancreatic ductal adenocarcinoma. It is of utmost importance to make an early correct differential diagnosis between these two diseases in order to identify the optimal therapeutic strategy and to avoid unnecessary laparotomy or pancreatic resection in AIP patients. Non-invasive imaging plays also an important role in therapy monitoring, in follow-up and in early identification of disease recurrence. PMID:25493001

  11. Non-invasive subcutaneous fat reduction: a review.

    PubMed

    Kennedy, J; Verne, S; Griffith, R; Falto-Aizpurua, L; Nouri, K

    2015-09-01

    The risks, financial costs and lengthy downtime associated with surgical procedures for fat reduction have led to the development of a number of non-invasive techniques. Non-invasive body contouring now represents the fastest growing area of aesthetic medicine. There are currently four leading non-invasive techniques for reducing localized subcutaneous adipose tissue: low-level laser therapy (LLLT), cryolipolysis, radio frequency (RF) and high-intensity focused ultrasound (HIFU). To review and compare leading techniques and clinical outcomes of non-invasive subcutaneous fat reduction. The terms 'non-invasive', 'low-level laser', 'cryolipolysis', 'ultrasound' and 'radio frequency' were combined with 'lipolysis', 'fat reduction' or 'body contour' during separate searches in the PubMed database. We identified 31 studies (27 prospective clinical studies and four retrospective chart reviews) with a total of 2937 patients that had been treated with LLLT (n = 1114), cryolipolysis (n = 706), HIFU (n = 843) or RF (n = 116) or other techniques (n = 158) for fat reduction or body contouring. A majority of these patients experienced significant and satisfying results without any serious adverse effects. The studies investigating these devices have all varied in treatment regimen, body locations, follow-up times or outcome operationalization. Each technique differs in offered advantages and severity of adverse effects. However, multiple non-invasive devices are safe and effective for circumferential reduction in local fat tissue by 2 cm or more across the abdomen, hips and thighs. Results are consistent and reproducible for each device and none are associated with any serious or permanent adverse effects. PMID:25664493

  12. Neural selection of the optimal optical signature for a rapid characterization of a submicrometer period grating

    NASA Astrophysics Data System (ADS)

    Robert, Stéphane; Mure-Ravaud, Alain; Thiria, Sylvie; Yacoub, Méziane; Badran, Fouad

    2004-08-01

    The characterization of gratings with small period-to-wavelength ratios can be achieved by solving the inverse problem of the diffraction. The use of a neural network has shown several advantages: it is a non-destructive, non-local and non-invasive method. However, although the calculation of results is instantaneous, the neural characterizations already published require the measurement of many diffracted intensities and can so need a long measurement time. We present, in this paper, a neural selection process called heuristic variable selection. This method reduces the number of diffractive efficiencies allowing a correct reconstruction of the profile shape according to an expected accuracy. In the same way, the non-redundancy of the data composing the optical signature is ensured. We relate a 1-μm period grating etched in silicon which could be characterized with only six measurements when a trapezoidal profile shape is assumed.

  13. An Acetone Nanosensor For Non-invasive Diabetes Detection

    NASA Astrophysics Data System (ADS)

    Wang, L.; Yun, X.; Stanacevic, M.; Gouma, P. I.

    2009-05-01

    Diabetes is a most common disease worldwide. Acetone in exhaled breath is a known biomarker of Type- 1 diabetes. An exhaled breath analyzer has been developed with the potential to diagnose diabetes as a non-invasive alternative of the currently used blood-based diagnostics. This device utilizes a chemiresistor based on ferroelectric tungsten oxide nanoparticles and detects acetone selectively in breath-simulated media. Real-time monitoring of the acetone concentration is feasible, potentially making this detector a revolutionary, non- invasive, diabetes diagnostic tool.

  14. Non-invasive brain stimulation in early rehabilitation after stroke.

    PubMed

    Blesneag, A V; Popa, L; Stan, A D

    2015-01-01

    The new tendency in rehabilitation involves non-invasive tools that, if applied early after stroke, promote neurorecovery. Repetitive transcranial magnetic stimulation and transcranial direct current stimulation may correct the disruption of cortical excitability and effectively contribute to the restoration of movement and speech. The present paper analyses the results of non-invasive brain stimulation (NIBS) trials, highlighting different aspects related to the repetitive transcranial magnetic stimulation frequency, transcranial direct current stimulation polarity, the period and stimulation places in acute and subacute ischemic strokes. The risk of adverse events, the association with motor or language recovery specific training, and the cumulative positive effect evaluation are also discussed. PMID:26361512

  15. Non-invasive activation of optogenetic actuators

    NASA Astrophysics Data System (ADS)

    Birkner, Elisabeth; Berglund, Ken; Klein, Marguerita E.; Augustine, George J.; Hochgeschwender, Ute

    2014-03-01

    The manipulation of genetically targeted neurons with light (optogenetics) continues to provide unprecedented avenues into studying the function of the mammalian brain. However, potential translation into the clinical arena faces a number of significant hurdles, foremost among them the need for insertion of optical fibers into the brain to deliver light to opsins expressed on neuronal membranes. In order to overcome these hardware-related problems, we have developed an alternative strategy for delivering light to opsins which does not involve fiber implants. Rather, the light is produced by a protein, luciferase, which oxidizes intravenously applied substrate, thereby emitting bioluminescence. In proof-ofprinciple studies employing a fusion protein of a light-generating luciferase to a light-sensing opsin (luminopsin), we showed that light emitted by Gaussia luciferase is indeed able to activate channelrhodopsin, allowing modulation of neuronal activity when expressed in cultured neurons. Here we assessed applicability of the concept in vivo in mice expressing luminopsins from viral vectors and from genetically engineered transgenes. The experiments demonstrate that intravenously applied substrate reaches neurons in the brain, causing the luciferase to produce bioluminescence which can be imaged in vivo, and that activation of channelrhodopsin by bioluminescence is sufficient to affect behavior. Further developments of such technology based on combining optogenetics with bioluminescence - i.e. combining lightsensing molecules with biologically produced light through luciferases - should bring optogenetics closer to clinical applications.

  16. Low Coherence Optic Source Characterization

    NASA Astrophysics Data System (ADS)

    Flores-Domínguez, C. E.; Ochoa-Valiente, R.; García-Trujillo, L. A.

    2015-01-01

    This work presents the results of characterization of the coherence length of an optic source using interferometric techniques and digital signal processing. Optic sources are not ideal because of random behavior in the emission process and spectral dispersion. Optical coherence is the ability of light to generate interference, either temporal or spatial. In time domain, coherence is expressed by the autocorrelation function. In case of monochromatic laser, it has larger coherence length, in the order of tenths to hundredth of meters, rather than a superluminiscent diode (SLD), which is shorter, in the orders of millimeters. This work presents a method for measuring coherence length using an automated Michelson interferometer and a SLD with central wavelength λ0 = 1302.4 nm and acquisition system.by means of a soundcard in a personal computer.

  17. Optical characterization of vocal folds using optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Lüerßen, Kathrin; Lubatschowski, Holger; Radicke, Nicole; Ptok, Martin

    2006-02-01

    The current standard procedure to ensure the diagnosis, if tissue is malignant, is still an invasive one. Optical coherence tomography (OCT) is a new non-invasive method to investigate biological tissue. In this study OCT was used on porcine and on human vocal folds. The optical penetration depth of the used radiation is up to 2 mm. Three different OCT application systems were used. The first is a high resolution OCT, which works in contact mode. It was used to examine porcine vocal folds ex vivo. Porcine vocal folds were assigned to defined areas and examined by OCT in contact mode followed by traditional histo-morphological analysis. The second OCT is fiber based. It also works in contact mode. Images of human vocal folds were done in contact mode. They were compared with a typical histo-morphological image of a human vocal fold. The third application system works in non contact to the tissue. It was integrated in a conventional laryngoscope. Human vocal folds were examined in vivo. Single layers of the vocal folds could be distinguished from each other with all used systems. Pathological alterations could be seen. Imaging is possible in real time. General anaesthesia is not necessary. OCT makes it possible to get a view under the surface of the vocal fold without being invasive.

  18. Reliable, Low Mass, Non-Invasive Pressure Transducers

    NASA Technical Reports Server (NTRS)

    Hartley, F.; Tovey, M.

    1999-01-01

    Mass is a major driver for future spacecraft and missions exposed to high radiation levels (i.e. Europa Orbiter) present even more challenge. A variety of non-invasive measurement techniques are in development that enables determination of pressures within a propulsion network.

  19. Method for non-invasive detection of ocular melanoma

    DOEpatents

    Lambrecht, Richard M.; Packer, Samuel

    1984-01-01

    There is described an apparatus and method for diagnosing ocular cancer that is both non-invasive and accurate which comprises two radiation detectors positioned before each of the patient's eyes which will measure the radiation level produced in each eye after the administration of a tumor-localizing radiopharmaceutical such as gallium-67.

  20. Method for non-invasive detection of ocular melanoma

    DOEpatents

    Lambrecht, R.M.; Packer, S.

    1984-10-30

    An apparatus and method is disclosed for diagnosing ocular cancer that is both non-invasive and accurate. The apparatus comprises two radiation detectors positioned before each of the patient's eyes which will measure the radiation level produced in each eye after the administration of a tumor-localizing radiopharmaceutical such as gallium-67. 2 figs.

  1. Non-invasive Prediction of Pork Loin Tenderness

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The present experiment was conducted to develop a non-invasive method to predict tenderness of pork loins. Boneless pork loins (n = 901) were evaluated either on line on the loin boning and trimming line of large-scale commercial plants (n = 465) or at the U.S. Meat Animal Research Center abattoir ...

  2. NON-INVASIVE NEUROTOXICITY ASSAY USING LARVAL MEDAKA

    EPA Science Inventory

    We present a method for non-invasive electrophysiological analysis of rapid escape responses in intact, freely behaving larval medaka (Oryzias latipes) before and after short-term exposure to environmental toxicants. ecordings are obtained as a larval medaka swims in a small cham...

  3. Non-invasive treatment options for focal cortical dysplasia

    PubMed Central

    WANG, TING-TING; ZHOU, DONG

    2016-01-01

    Focal cortical dysplasia (FCD) presents a strong clinical challenge especially for the treatment of the associated epilepsy. Epilepsy in FCD is often treatment-resistant and constitutes 50% of treatment-resistant cases. Antiepileptic drugs (AEDs) have been widely used in the treatment of FCD. However, evidence to suggest their specific effect on the treatment of FCD remains to be established. In view of this resistance, several alternative treatments have been suggested. Although treatment currently involves surgical management, non-invasive treatments have been identified. The aim of the present review, was to assess non-invasive management strategies including, i) mammalian target of rapamycin (mTOR) inhibitors, ii) ketogenic diet (KD), and iii) vagus nerve stimulation (VNS). In addition, we discussed the literature available regarding the use of AEDs in FCD. Experiments conducted with mammals detailing rapamycin gene mutations in FCD have produced vital information for exploring treatment options using mTOR inhibitors. Of note is the importance of KD in children with FCD. This diet has been shown to modify disease progression by attenuating chromatin modification, a master regulator for gene expression and functional adaptation of the cell. FCD has also been studied widely with neurostimulation techniques. The outcomes of these techniques have been found to be variable. For widespread dysplasias, VNS has been shown to produce responder rates of >50%. Nevertheless, non-invasive cranial nerve stimulation techniques such as transcutaneous VNS and non-invasive VNS are gaining better patient compatibility, albeit their efficacy remains to be established. PMID:27168769

  4. Eyeblink Conditioning: A Non-Invasive Biomarker for Neurodevelopmental Disorders

    ERIC Educational Resources Information Center

    Reeb-Sutherland, Bethany C.; Fox, Nathan A.

    2015-01-01

    Eyeblink conditioning (EBC) is a classical conditioning paradigm typically used to study the underlying neural processes of learning and memory. EBC has a well-defined neural circuitry, is non-invasive, and can be employed in human infants shortly after birth making it an ideal tool to use in both developing and special populations. In addition,…

  5. Strategies for non-invasive delivery of biologics.

    PubMed

    Chung, Seung Woo; Hil-lal, Taslim A; Byun, Youngro

    2012-07-01

    Macromolecular therapeutics, in particular, many biologics, is the most advancing category of drugs over conventional chemical drugs. The potency and specificity of the biologics for curing certain disease made them to be a leading compound in the pharmaceutical industry. However, due to their intrinsic nature, including high molecular weight, hydrophilicity and instability, they are difficult to be administered via non-invasive route. This is a major quest especially in biologics, as they are frequently used clinically for chronic disorders, which requires long-term administration. Therefore, many efforts have been made to develop formulation for non-invasive administration, in attempt to improve patient compliance and convenience. In this review, strategies for non-invasive delivery, in particular, oral, pulmonary and nasal delivery, that are recently adopted for delivery of biologics are discussed. Insulin, calcitonin and heparin were mainly focused for the discussion as they could represent protein, polypeptide and polysaccharide drugs, respectively. Many recent attempts for non-invasive delivery of biologics are compared to provide an insight of developing successful delivery system. PMID:22632037

  6. The Book of Kells: a non-invasive MOLAB investigation by complementary spectroscopic techniques.

    PubMed

    Doherty, B; Daveri, A; Clementi, C; Romani, A; Bioletti, S; Brunetti, B; Sgamellotti, A; Miliani, C

    2013-11-01

    This paper highlights the efficacy of non-invasive portable spectroscopy for assessing the execution technique and constituent materials in one of the most important medieval manuscripts, the Book of Kells. An aimed campaign of in situ measurements by the MObile LABoratory (MOLAB) has analyzed its elemental composition and vibrational and electronic molecular properties. The ample analytical toolbox has afforded complementary diagnostic information of the pigment palette permitting the characterization of both inorganic and organic materials as pigments and dyes in the white, purple, blue, red, orange, green and black areas. In particular, the novel widespread use of calcinated gypsum (anhydrite) as both a white pigment and in correlation to the organic dyes in this manuscript has been noted. The non-invasive identification of the organic dye orchil is significant considering its rare non invasive detection in medieval manuscripts. Finally the occurrence of particular alterations of the organic black areas giving rise to calcium carboxylate and calcium oxalate has been specifically highlighted. Importantly, this work elaborates complex aspects of the employed painting materials which have given rise to numerous significant points of interest for a more elaborate understanding of this Irish treasure. PMID:23850791

  7. The Book of Kells: A non-invasive MOLAB investigation by complementary spectroscopic techniques

    NASA Astrophysics Data System (ADS)

    Doherty, B.; Daveri, A.; Clementi, C.; Romani, A.; Bioletti, S.; Brunetti, B.; Sgamellotti, A.; Miliani, C.

    2013-11-01

    This paper highlights the efficacy of non-invasive portable spectroscopy for assessing the execution technique and constituent materials in one of the most important medieval manuscripts, the Book of Kells. An aimed campaign of in situ measurements by the MObile LABoratory (MOLAB) has analyzed its elemental composition and vibrational and electronic molecular properties. The ample analytical toolbox has afforded complementary diagnostic information of the pigment palette permitting the characterization of both inorganic and organic materials as pigments and dyes in the white, purple, blue, red, orange, green and black areas. In particular, the novel widespread use of calcinated gypsum (anhydrite) as both a white pigment and in correlation to the organic dyes in this manuscript has been noted. The non-invasive identification of the organic dye orchil is significant considering its rare non invasive detection in medieval manuscripts. Finally the occurrence of particular alterations of the organic black areas giving rise to calcium carboxylate and calcium oxalate has been specifically highlighted. Importantly, this work elaborates complex aspects of the employed painting materials which have given rise to numerous significant points of interest for a more elaborate understanding of this Irish treasure.

  8. Optical characterization of beef muscle

    NASA Astrophysics Data System (ADS)

    Yao, Gang; Xia, Jinjun

    2005-11-01

    An objective and reliable method for meat quality measurement will benefit both consumers and meat industry. Among various techniques, optical methods have the advantage of being fast, flexible, inexpensive and nondestructive, which are important characteristics for online quality control. Although there have been great progress in this area, many results are inconsistent and controversial because of the lack of fundamental understanding of in light-meat interactions. Optical measurements on meat tissues are affected by both meat scattering and absorption properties. In the project, a method based on diffuse approximation solution of light transport in tissue was used to derive meat scattering and absorption coefficients. Differentiating muscle scattering properties from absorption properties are important for muscle characterization because they represent distinctly different aspects of muscle physical and chemical components. Our preliminary results showed that scattering coefficients can detect variations in beef steak tenderness. This new technique is promising to be used as an indicator for beef tenderness. However, a more extensive study with larger sample population will be necessary to fully test the capability of using optical scattering for beef tenderness characterization.

  9. Optical Characterization of Biological Tissues

    NASA Astrophysics Data System (ADS)

    Mimun, L.; Barrera, Frederick; Sardar, Dhiraj; Tsin, Andrew

    2008-03-01

    University of Texas at San Antonio, San Antonio, Texas 78249 An in-depth characterization of the optical properties of biological tissues has been performed. The wavelength-dependent total diffuse reflection (Rd) and total transmission (Tt) measurements have been taken for individual tissues by using a double-integrating sphere setup. The index of refraction of the tissues will be determined using conventional optical techniques. The Kubelka Munk theory is applied to determine the scattering and absorption coefficients of these samples from the measurements of diffuse transmission and reflection. A thorough study of the scattering characteristics of these tissues has been made. *This work was supported in part by the NSF sponsored Center for Biophotonics Science and Technology (CBST) at UC Davis under Cooperative Agreement No. PHY 0120999.

  10. Dielectric spectroscopy for non-invasive monitoring of epithelial cell differentiation within three-dimensional scaffolds

    NASA Astrophysics Data System (ADS)

    Daoud, Jamal; Asami, Koji; Rosenberg, Lawrence; Tabrizian, Maryam

    2012-08-01

    In this study, we introduce a cellular differentiation cellular model based on dielectric spectroscopy that characterizes epithelial differentiation processes. Non-invasive cellular monitoring was achieved within a three-dimensional microenvironment consisting of a cell-containing collagen I gel seeded onto microfabricated scaffolds. In this proof-of-concept investigation, Madin-Darby canine kidney cells were cultured within microfabricated, geometrically controlled scaffolds and allowed us to differentiate to hollow cyst-like structures. This transformation within the three-dimensional environment is monitored and characterized through dielectric spectroscopy while maintaining cell culture in vitro.

  11. Optical systems for non-invasive cardiovascular biosensing

    NASA Astrophysics Data System (ADS)

    Erts, R.; Spigulis, J., Sr.; Ozols, M.

    2005-09-01

    Three portable prototype devices for cardiovascular biosensing based on reflection-type photoplethysmography (PPG) principle have been designed and clinically tested. The single-channel PPG finger sensor provides real-time measurements with fast calculation of the mean single-period PPG signal shape ("cardiovascular fingerprint", potentially useful for recognition). The dual-channel PPG system gives additional possibility to monitor on-line the arterial pulse wave transit time and its responses to physical exercises. The four-channel PPG system proved to be applicable for fast detection of cardiovascular pathologies, e.g. arterial occlusions in extremities. Design principles and software algorithms of the regarded devices will be discussed, as well as the results of recent clinical tests.

  12. Future Imaging Alternatives: The Clinical Non-invasive Modalities in Diagnosis of Oral Squamous Cell Carcinoma (OSCC)

    PubMed Central

    Omar, Esam

    2015-01-01

    Background : Oral squamous cell carcinoma (OSCC) has a remarkably high incidence worldwide, and a fairly serious prognosis. This is encouraging further research into advanced technologies for non-invasive methods of making early diagnoses, ideally in primary care settings. Method : In this article, the available objective Non-imaging methods for diagnosing OSCC have been reviewed. MEDLINE, EMBASE, the Cochrane Library, and CINAHL have been searched for advanced technologies of non-invasive methods in diagnosis of OSCC, including oral brush biopsy, optical biopsy, saliva-based oral cancer diagnosis and others. Results : Toluidine blue, one of the oldest non-invasive methods for diagnosing OSCC, is unreliable because of its subjectivity, as it is dependent on the experience of the examiner. The diagnosis of Oral carcinoma by Oral brush biopsy with exfoliative cytology based on nano-bio-chip sensor platform shows 97–100% sensitivity and 86% specificity. Another promising non-invasive technique for OSCC diagnosis is saliva-based oral cancer diagnosis, which is an alternative to serum testing. Optical biopsy, which uses the technology of spectroscopy, can be used to detect changes at a sub-cellular level; thus, it provides information that may not be available with conventional histology with reliable sensitivity and specificity. Conclusion : It is clearly evident that screening and early effective detection of cancer and pre-cancerous lesions have the potential to reduce the morbidity and mortality of this disease. The imaging technologies are subjective procedures since all of them require interpretation and significantly affected by the examiner experience. These make further research for advanced objective procedures. Saliva-based oral cancer diagnosis and optical biopsy are promising objective non-invasive methods for diagnosing OSCC. They are easy to perform clinically at primary care set. They show promising pathways for future development of more effective

  13. Non-invasive diagnostic techniques in the diagnosis of squamous cell carcinoma.

    PubMed

    Warszawik-Hendzel, Olga; Olszewska, Małgorzata; Maj, Małgorzata; Rakowska, Adriana; Czuwara, Joanna; Rudnicka, Lidia

    2015-12-31

    Squamous cell carcinoma is the second most common cutaneous malignancy after basal cell carcinoma. Although the gold standard of diagnosis for squamous cell carcinoma is biopsy followed by histopathology evaluation, optical non-invasive diagnostic tools have obtained increased attention. Dermoscopy has become one of the basic diagnostic methods in clinical practice. The most common dermoscopic features of squamous cell carcinoma include clustered vascular pattern, glomerular vessels and hyperkeratosis. Under reflectance confocal microscopy, squamous cell carcinoma shows an atypical honeycomb or disarranged pattern of the spinous-granular layer of the epidermis, round nucleated bright cells in the epidermis and round vessels in the dermis. High frequency ultrasound and optical coherence tomography may be helpful in predominantly in pre-surgical evaluation of tumor size. Emerging non-invasive or minimal invasive techniques with possible application in the diagnosis of squamous cell carcinoma of the skin, lip, oral mucosa, vulva or other tissues include high-definition optical coherence tomography, in vivo multiphoton tomography, direct oral microscopy, electrical impedance spectroscopy, fluorescence spectroscopy, Raman spectroscopy, elastic scattering spectroscopy, differential path-length spectroscopy, nuclear magnetic resonance spectroscopy, and angle-resolved low coherence interferometry. PMID:26848316

  14. Skin rejuvenation with non-invasive pulsed electric fields.

    PubMed

    Golberg, Alexander; Khan, Saiqa; Belov, Vasily; Quinn, Kyle P; Albadawi, Hassan; Felix Broelsch, G; Watkins, Michael T; Georgakoudi, Irene; Papisov, Mikhail; Mihm, Martin C; Austen, William G; Yarmush, Martin L

    2015-01-01

    Degenerative skin diseases affect one third of individuals over the age of sixty. Current therapies use various physical and chemical methods to rejuvenate skin; but since the therapies affect many tissue components including cells and extracellular matrix, they may also induce significant side effects, such as scarring. Here we report on a new, non-invasive, non-thermal technique to rejuvenate skin with pulsed electric fields. The fields destroy cells while simultaneously completely preserving the extracellular matrix architecture and releasing multiple growth factors locally that induce new cells and tissue growth. We have identified the specific pulsed electric field parameters in rats that lead to prominent proliferation of the epidermis, formation of microvasculature, and secretion of new collagen at treated areas without scarring. Our results suggest that pulsed electric fields can improve skin function and thus can potentially serve as a novel non-invasive skin therapy for multiple degenerative skin diseases. PMID:25965851

  15. Skin Rejuvenation with Non-Invasive Pulsed Electric Fields

    PubMed Central

    Golberg, Alexander; Khan, Saiqa; Belov, Vasily; Quinn, Kyle P.; Albadawi, Hassan; Felix Broelsch, G.; Watkins, Michael T.; Georgakoudi, Irene; Papisov, Mikhail; Mihm Jr., Martin C.; Austen Jr., William G.; Yarmush, Martin L.

    2015-01-01

    Degenerative skin diseases affect one third of individuals over the age of sixty. Current therapies use various physical and chemical methods to rejuvenate skin; but since the therapies affect many tissue components including cells and extracellular matrix, they may also induce significant side effects, such as scarring. Here we report on a new, non-invasive, non-thermal technique to rejuvenate skin with pulsed electric fields. The fields destroy cells while simultaneously completely preserving the extracellular matrix architecture and releasing multiple growth factors locally that induce new cells and tissue growth. We have identified the specific pulsed electric field parameters in rats that lead to prominent proliferation of the epidermis, formation of microvasculature, and secretion of new collagen at treated areas without scarring. Our results suggest that pulsed electric fields can improve skin function and thus can potentially serve as a novel non-invasive skin therapy for multiple degenerative skin diseases. PMID:25965851

  16. Non-invasive microsensors for studying cell/tissue physiology

    NASA Astrophysics Data System (ADS)

    Vanegas, D. C.; Taguchi, M.; Chaturvedi, P.; Burrs, S.; McLamore, E. S.

    2013-05-01

    Non-invasive tools that allow real-time quantification of molecules relevant to metabolism, homeostasis, and cell signaling in cells and tissue are of great importance for studying physiology. Several microsensor technologies have been developed to monitor concentration of molecules such as ions, oxygen, electroactive molecules (e.g., nitric oxide, hydrogen peroxide), and biomolecules (e.g., sugars, hormones). The major challenges for microsensors are overcoming relatively low sensitivity and low signal-to-noise ratio. Modern approaches for enhancing microsensor performance focus on the incorporation of catalytic nanomaterials to increase sensitivity, reduce response time, and increase operating range. To improve signal-to-noise ratio, a non-invasive microsensor modality called self-referencing (SR) is being applied. The SR technique allows measurement of temporal and spatial transport dynamics at the cell, tissue, organ, and organismal level.

  17. Skin Rejuvenation with Non-Invasive Pulsed Electric Fields

    NASA Astrophysics Data System (ADS)

    Golberg, Alexander; Khan, Saiqa; Belov, Vasily; Quinn, Kyle P.; Albadawi, Hassan; Felix Broelsch, G.; Watkins, Michael T.; Georgakoudi, Irene; Papisov, Mikhail; Mihm, Martin C., Jr.; Austen, William G., Jr.; Yarmush, Martin L.

    2015-05-01

    Degenerative skin diseases affect one third of individuals over the age of sixty. Current therapies use various physical and chemical methods to rejuvenate skin; but since the therapies affect many tissue components including cells and extracellular matrix, they may also induce significant side effects, such as scarring. Here we report on a new, non-invasive, non-thermal technique to rejuvenate skin with pulsed electric fields. The fields destroy cells while simultaneously completely preserving the extracellular matrix architecture and releasing multiple growth factors locally that induce new cells and tissue growth. We have identified the specific pulsed electric field parameters in rats that lead to prominent proliferation of the epidermis, formation of microvasculature, and secretion of new collagen at treated areas without scarring. Our results suggest that pulsed electric fields can improve skin function and thus can potentially serve as a novel non-invasive skin therapy for multiple degenerative skin diseases.

  18. Non invasive ventilation as an additional tool for exercise training.

    PubMed

    Ambrosino, Nicolino; Cigni, Paolo

    2015-01-01

    Recently, there has been increasing interest in the use of non invasive ventilation (NIV) to increase exercise capacity. In individuals with COPD, NIV during exercise reduces dyspnoea and increases exercise tolerance. Different modalities of mechanical ventilation have been used non-invasively as a tool to increase exercise tolerance in COPD, heart failure and lung and thoracic restrictive diseases. Inspiratory support provides symptomatic benefit by unloading the ventilatory muscles, whereas Continuous Positive Airway Pressure (CPAP) counterbalances the intrinsic positive end-expiratory pressure in COPD patients. Severe stable COPD patients undergoing home nocturnal NIV and daytime exercise training showed some benefits. Furthermore, it has been reported that in chronic hypercapnic COPD under long-term ventilatory support, NIV can also be administered during walking. Despite these results, the role of NIV as a routine component of pulmonary rehabilitation is still to be defined. PMID:25874110

  19. SQUID magnetometry applied as non-invasive electroanalytic chemical technique

    SciTech Connect

    Jette, B.D.; MacVicar, M.L.A. )

    1991-03-01

    This paper reports on a SQUID magnetometer, employed as a highly sensitive ammeter, used to perform standard electroanalytic chemical measurements non- invasively. Specifically, the magnetic fields generated by the net ionic movement in the solution of a driven electrochemical system is detected by the gradiometer coils. The SQUID signal can then be compared to conventional current measurements. One such standard measurement investigated is Cyclic Voltametry (CV) which determines the I-V characteristics of an electrochemical system yielding critical kinetic parameters.

  20. Non-invasive diagnosis of advanced fibrosis and cirrhosis.

    PubMed

    Sharma, Suraj; Khalili, Korosh; Nguyen, Geoffrey Christopher

    2014-12-01

    Liver cirrhosis is a common and growing public health problem globally. The diagnosis of cirrhosis portends an increased risk of morbidity and mortality. Liver biopsy is considered the gold standard for diagnosis of cirrhosis and staging of fibrosis. However, despite its universal use, liver biopsy is an invasive and inaccurate gold standard with numerous drawbacks. In order to overcome the limitations of liver biopsy, a number of non-invasive techniques have been investigated for the assessment of cirrhosis. This review will focus on currently available non-invasive markers of cirrhosis. The evidence behind the use of these markers will be highlighted, along with an assessment of diagnostic accuracy and performance characteristics of each test. Non-invasive markers of cirrhosis can be radiologic or serum-based. Radiologic techniques based on ultrasound, magnetic resonance imaging and elastography have been used to assess liver fibrosis. Serum-based biomarkers of cirrhosis have also been developed. These are broadly classified into indirect and direct markers. Indirect biomarkers reflect liver function, which may decline with the onset of cirrhosis. Direct biomarkers, reflect extracellular matrix turnover, and include molecules involved in hepatic fibrogenesis. On the whole, radiologic and serum markers of fibrosis correlate well with biopsy scores, especially when excluding cirrhosis or excluding fibrosis. This feature is certainly clinically useful, and avoids liver biopsy in many cases. PMID:25492996

  1. Non invasive assessment of the human tear film dynamics.

    PubMed

    Ring, M H; Rabensteiner, D F; Horwath-Winter, J; Boldin, I; Schrödl, F; Reitsamer, H; Haslwanter, T

    2015-11-01

    Dry eye disease, or keratoconjunctivitis sicca, is a multifactorial syndrome with altered tear film homeostasis leading to ocular irritations. These alterations cause discomfort and stress for the patient, but only a few objective parameters allow for proper differential diagnosis into different subtypes of this condition. The mostly invasively performed standard assessment procedures for tear film diagnosis are manifold, but often correlate quite poorly with the subjectively reported symptoms. Due to the inherent limitations, e.g. the subjectivity of the commonly performed invasive tests, a number of devices have been developed to assess the human tear film non-invasively. Since the production, delivery, distribution and drainage of the tear film is a dynamic process, we have focused our review on non-invasive methods which are capable of continuous or repetitive observations of the tear film during an inter-blink interval. These dynamic methods include (1) Interferometry, (2) Pattern Projection, (3) Aberrometry, (4) Thermography; and (5) Evaporimetry. These techniques are discussed with respect to their diagnostic value, both for screening and differential diagnostic of Dry Eye Disease. Many of the parameters obtained from these tests have been shown to have the potential to reliably discriminate patients from healthy subjects, especially when the tests are performed automatically and objectively. The differentiation into subtypes based solely on a single, dynamic parameter may not be feasible, but the combination of non-invasively performed procedures may provide good discrimination results. PMID:26406882

  2. Non-invasive evaluation of arrhythmic risk in dilated cardiomyopathy: From imaging to electrocardiographic measures

    PubMed Central

    Iacoviello, Massimo; Monitillo, Francesco

    2014-01-01

    Malignant ventricular arrhythmias are a major adverse event and worsen the prognosis of patients affected by ischemic and non-ischemic dilated cardiomyopathy. The main parameter currently used to stratify arrhythmic risk and guide decision making towards the implantation of a cardioverter defibrillator is the evaluation of the left ventricular ejection fraction. However, this strategy is characterized by several limitations and consequently additional parameters have been suggested in order to improve arrhythmic risk stratification. The aim of this review is to critically revise the prognostic significance of non-invasive diagnostic tools in order to better stratify the arrhythmic risk prognosis of dilated cardiomyopathy patients. PMID:25068017

  3. Non-Invasive Brain Stimulation for Treatment of Focal Hand Dystonia: Update and Future Direction

    PubMed Central

    Cho, Hyun Joo; Hallett, Mark

    2016-01-01

    Focal hand dystonia (FHD) is characterized by excessive and unwanted muscle activation in both the hand and arm resulting in impaired performance in particular tasks. Understanding the pathophysiology of FHD has progressed significantly for several decades and this has led to consideration of other potential therapies such as non-invasive brain stimulation (NIBS). A number of studies have been conducted to develop new therapy for FHD using transcranial magnetic stimulation and transcranial direct current stimulation. In this paper, we review previous studies and describe the potential therapeutic use of NIBS for FHD. We also discuss the future direction of NIBS to treat FHD. PMID:27240806

  4. Dynamic characterization of satellite components through non-invasive methods

    SciTech Connect

    Mullins, Joshua G; Wiest, Heather K; Mascarenas, David D. L.; Macknelly, David

    2010-10-21

    The rapid deployment of satellites is hindered by the need to flight-qualify their components and the resulting mechanical assembly. Conventional methods for qualification testing of satellite components are costly and time consuming. Furthermore, full-scale vehicles must be subjected to launch loads during testing. This harsh testing environment increases the risk of component damage during qualification. The focus of this research effort was to assess the performance of Structural Health Monitoring (SHM) techniques as a replacement for traditional vibration testing. SHM techniques were applied on a small-scale structure representative of a responsive satellite. The test structure consisted of an extruded aluminum space-frame covered with aluminum shear plates, which was assembled using bolted joints. Multiple piezoelectric patches were bonded to the test structure and acted as combined actuators and sensors. Various methods of SHM were explored including impedance-based health monitoring, wave propagation, and conventional frequency response functions. Using these methods in conjunction with finite element modelling, the dynamic properties of the test structure were established and areas of potential damage were identified and localized. The adequacy of the results from each SHM method was validated by comparison to results from conventional vibration testing.

  5. Dynamic characterization of satellite components through non-invasive methods

    SciTech Connect

    Mullens, Joshua G; Wiest, Heather K; Mascarenas, David D; Park, Gyuhae

    2011-01-24

    The rapid deployment of satellites is hindered by the need to flight-qualify their components and the resulting mechanical assembly. Conventional methods for qualification testing of satellite components are costly and time consuming. Furthermore, full-scale vehicles must be subjected to launch loads during testing. The harsh testing environment increases the risk of component damage during qualification. The focus of this research effort was to assess the performance of Structural Health Monitoring (SHM) techniques as replacement for traditional vibration testing. SHM techniques were applied on a small-scale structure representative of a responsive satellite. The test structure consisted of an extruded aluminum space-frame covered with aluminum shear plates, which was assembled using bolted joints. Multiple piezoelectric patches were bonded to the test structure and acted as combined actuators and sensors. Various methods of SHM were explored including impedance-based health monitoring, wave propagation, and conventional frequency response functions. Using these methods in conjunction with finite element modeling, the dynamic properties of the test structure were established and areas of potential damage were identified and localized. The adequacy of the results from each SHM method was validated by comparison to results from conventional vibration testing.

  6. Nondestructive optical characterization of MEMS

    NASA Astrophysics Data System (ADS)

    Pryputniewicz, Ryszard J.

    2013-10-01

    Advances in emerging technology of microelectromechanical systems (MEMS) are one of the most challenging tasks in today's experimental mechanics. More specifically, development of these miniature devices requires sophisticated design, analysis, fabrication, testing, and characterization tools that have multiphysics and multiscale capabilities, especially as MEMS are being developed for use at harsh conditions. In harsh-environment and high-performance guidance applications inertial sensors must be sensitive to low rates of rotation yet survive the high blast loads associated with the initial launch. In this multi-year study a set of tuning fork gyroscopes (TFGs) were subjected to a series of increasing g-loads (culminating at approximately 60,000 g's) with measurements of shape made after each test. High-g-testing was conducted within the large test chamber using a custom fabricated mini powder gun. A custom set of test sample packages were hermetically sealed with glass lids to allow optical inspection of components while preserving the operating (vacuum) environment. Optical and interferometric measurements have been made prior to and after each shock g-loading. The shape of the TFG test articles was measured using optoelectronic laser interferometric microscope (OELIM) methodology. Line traces were extracted from pertinent structures to clearly examine changes in the TFG. Failure of the die was observed in the form of fractures below the chip surface as well as fractures in the glass lid sealing the package.

  7. Non-invasive multimodal functional imaging of the intestine with frozen micellar naphthalocyanines

    NASA Astrophysics Data System (ADS)

    Zhang, Yumiao; Jeon, Mansik; Rich, Laurie J.; Hong, Hao; Geng, Jumin; Zhang, Yin; Shi, Sixiang; Barnhart, Todd E.; Alexandridis, Paschalis; Huizinga, Jan D.; Seshadri, Mukund; Cai, Weibo; Kim, Chulhong; Lovell, Jonathan F.

    2014-08-01

    There is a need for safer and improved methods for non-invasive imaging of the gastrointestinal tract. Modalities based on X-ray radiation, magnetic resonance and ultrasound suffer from limitations with respect to safety, accessibility or lack of adequate contrast. Functional intestinal imaging of dynamic gut processes has not been practical using existing approaches. Here, we report the development of a family of nanoparticles that can withstand the harsh conditions of the stomach and intestine, avoid systemic absorption, and provide good optical contrast for photoacoustic imaging. The hydrophobicity of naphthalocyanine dyes was exploited to generate purified ∼20 nm frozen micelles, which we call nanonaps, with tunable and large near-infrared absorption values (>1,000). Unlike conventional chromophores, nanonaps exhibit non-shifting spectra at ultrahigh optical densities and, following oral administration in mice, passed safely through the gastrointestinal tract. Non-invasive, non-ionizing photoacoustic techniques were used to visualize nanonap intestinal distribution with low background and remarkable resolution, and enabled real-time intestinal functional imaging with ultrasound co-registration. Positron emission tomography following seamless nanonap radiolabelling allowed complementary whole-body imaging.

  8. Non-invasive, Multimodal Functional Imaging of the Intestine with Frozen Micellar Naphthalocyanines

    PubMed Central

    Zhang, Yumiao; Jeon, Mansik; Rich, Laurie J.; Hong, Hao; Geng, Jumin; Zhang, Yin; Shi, Sixiang; Barnhart, Todd E.; Alexandridis, Paschalis; Huizinga, Jan D.; Seshadri, Mukund; Cai, Weibo; Kim, Chulhong; Lovell, Jonathan F.

    2014-01-01

    Overview There is a need for safer and improved methods for non-invasive imaging of the gastrointestinal tract. Modalities based on X-ray radiation, magnetic resonance and ultrasound suffer from limitations with respect to safety, accessibility or lack of adequate contrast. Functional intestinal imaging of dynamic gut processes has not been practical using existing approaches. Here, we report the development of a family of nanoparticles that can withstand the harsh conditions of the stomach and intestine, avoid systemic absorption, and give rise to good optical contrast for photoacoustic imaging. The hydrophobicity of naphthalocyanine dyes was exploited to generate purified ~20 nm frozen micelles, which we call nanonaps, with tunable and large near-infrared absorption values (>1000). Unlike conventional chromophores, nanonaps exhibited non-shifting spectra at ultrahigh optical densities and, following oral administration in mice, passed safely through the gastrointestinal tract. Non-invasive, non-ionizing photoacoustic techniques were used to visualize nanonap intestinal distribution with low background and remarkable resolution with 0.5 cm depth, and enabled real-time intestinal functional imaging with ultrasound co-registration. Positron emission tomography following seamless nanonap radiolabelling allowed complementary whole body imaging. PMID:24997526

  9. The immunological response created by interstitial and non-invasive laser immunotherapy

    NASA Astrophysics Data System (ADS)

    Bahavar, Cody F.; Zhou, Feifan; Hasanjee, Aamr M.; West, Connor L.; Nordquist, Robert E.; Hode, Tomas; Liu, Hong; Chen, Wei R.

    2015-03-01

    Laser immunotherapy (LIT) is an innovative cancer modality that uses laser irradiation and immunological stimulation to treat late-stage, metastatic cancers. LIT can be performed through either interstitial or non-invasive laser irradiation. Although LIT is still in development, recent clinical trials have shown that it can be used to successfully treat patients with late-stage breast cancer and melanoma. The development of LIT has been focused on creating an optimal immune response created by irradiating the tumor. One important factor that could enhance the immune response is the duration of laser irradiation. Irradiating the tumor for a shorter or longer amount of time could weaken the immune response created by LIT. Another factor that could weaken this immune response is the proliferation of regulatory T cells (TRegs) in response to the laser irradiation. However, low dose cyclophosphamide (CY) can help suppress the proliferation of TRegs and help create a more optimal immune response. An additional factor that could weaken the effectiveness of LIT is the selectivity of the laser. If LIT is performed non-invasively, then deeply embedded tumors and highly pigmented skin could cause an uneven temperature distribution inside the tumor. To solve this problem, an immunologically modified carbon nanotube system was created by using an immunoadjuvant known as glycated chitosan (GC) as a surfactant for single-walled carbon nanotubes (SWNTs) to immunologically modify SWNTs. SWNT-GC retains the optical properties of SWNTs and the immunological functions of GC to help increase the selectivity of the laser and create a more optimal immune response. In this preliminary study, tumor-bearing rats were treated with LIT either interstitially by an 805-nm laser with GC and low-dose CY, or non-invasively by a 980-nm laser with SWNT-GC. The goal was to observe the effects of CY on the immune response induced by LIT and to also determine the effect of irradiation duration for

  10. A simple non-invasive method for measuring gross brain size in small live fish with semi-transparent heads

    PubMed Central

    2014-01-01

    This paper describes a non-invasive method for estimating gross brain size in small fish with semi-transparent heads, using system camera equipment. Macro-photographs were taken from above on backlit free-swimming fish undergoing light anaesthesia. From the photographs, the width of the optic tectum was measured. This measure (TeO-measure) correlates well with the width of the optic tectum as measured from out-dissected brains in both brown trout fry and zebrafish (Pearson r > 0.90). The TeO-measure also correlates well with overall brain wet weight in brown trout fry (r = 0.90), but less well for zebrafish (r = 0.79). A non-invasive measure makes it possible to quickly assess brain size from a large number of individuals, as well as repeatedly measuring brain size of live individuals allowing calculation of brain growth. PMID:25279266

  11. Towards a smart non-invasive fluid loss measurement system.

    PubMed

    Suryadevara, N K; Mukhopadhyay, S C; Barrack, L

    2015-04-01

    In this article, a smart wireless sensing non-invasive system for estimating the amount of fluid loss, a person experiences while physical activity is presented. The system measures three external body parameters, Heart Rate, Galvanic Skin Response (GSR, or skin conductance), and Skin Temperature. These three parameters are entered into an empirically derived formula along with the user's body mass index, and estimation for the amount of fluid lost is determined. The core benefit of the developed system is the affluence usage in combining with smart home monitoring systems to care elderly people in ambient assisted living environments as well in automobiles to monitor the body parameters of a motorist. PMID:25686913

  12. Non-invasive techniques for determining musculoskeleton body composition

    SciTech Connect

    Cohn, S.H.

    1984-01-01

    In vivo neutron activation analysis, combined with gamma spectrometry, has ushered in a new era of clinical diagnosis and evaluation of therapies, as well as investigation into and modelling of body composition in both normal individuals and patients suffering from various diseases and dysfunctions. Body composition studies have provided baseline data on such vital constituents as nitrogen, potassium and calcium. The non-invasive measurement techniques are particularly suitable for study of the musculo-skeletal changes in body composition. Of particular relevance here is the measurement of calcium loss in astronauts during prolonged space flights.

  13. A simple highly efficient non invasive EMG-based HMI.

    PubMed

    Vitiello, N; Olcese, U; Oddo, C M; Carpaneto, J; Micera, S; Carrozza, M C; Dario, P

    2006-01-01

    Muscle activity recorded non-invasively is sufficient to control a mobile robot if it is used in combination with an algorithm for its asynchronous analysis. In this paper, we show that several subjects successfully can control the movements of a robot in a structured environment made up of six rooms by contracting two different muscles using a simple algorithm. After a small training period, subjects were able to control the robot with performances comparable to those achieved manually controlling the robot. PMID:17945773

  14. [Focusing properties of picosecond electric pulses in non-invasive cancer treatment].

    PubMed

    Long, Zaiquan; Yao, Chenguo; Li, Chengxiang; Mi, Yan; Sun, Caixin

    2010-10-01

    In the light of optical theory, we advanc an ultra-wideband impulse radiating antenna (IRA) which is composed of an ellipsoidal reflector and a cone radiator. The high-intensity ultra-short electric pulses radiated by IRA can be transferred into the deep target in tissue non-invasively and be focused effectively. With the focused picosecond electric pulses, the organelles (mitochondria) transmembrane potential shall change to collapse under which the tumor cells will be targetly induced to apoptosis, so the method of non-invasive treatment of tumors would be achieved. Based on the time-domain electromagnetic field theory, the propagation characteristics of picosecond electric pulses were analyzed with and without the context of biological tissue, respectively. The results show that the impulse characteristics of input pulse were maintained and the picosecond electric pulses can keep high resolution in target areas. Meanwhile, because of the dispersive nature of medium, the pulse amplitude of the pulses will attenuate and the pulse width will be broadened. PMID:21089684

  15. A phantom with pulsating artificial vessels for non-invasive fetal pulse oximetry.

    PubMed

    Laqua, Daniel; Pollnow, Stefan; Fischer, Jan; Ley, Sebastian; Husar, Peter

    2014-01-01

    Arterial oxygen saturation of the fetus is an important parameter for monitoring its physical condition. During labor and delivery the transabdominal non-invasive fetal pulse oximetry could minimize the risk for mother and fetus, compared to other existing invasive examination methods. In this contribution, we developed a physical-like phantom to investigate new sensor circuits and algorithms of a non-invasive diagnostic method for fetal pulse oximetry. Hence, the developed artificial vascular system consists of two independent tube systems representing the maternal and fetal vessel system. The arterial blood pressure is reproduced with a pre-pressure and an artificial vascular system. Each pulse wave can be reproduced, by digital control of a proportional valve, adjustable viscoelastic elements, and resistances. The measurements are performed by pressure transducers, optical sensor units, and a coplanar capacitive sensor. Transmission and reflection measurements have shown that the fetal and maternal pulse waves can be reproduced qualitatively. The measured light represents the transabdominal modulated signal on an abdomen of a pregnant woman. PMID:25571272

  16. Non-invasive intravital imaging of cellular differentiation with a bright red-excitable fluorescent protein

    PubMed Central

    Chu, Jun; Haynes, Russell D; Corbel, Stéphane Y; Li, Pengpeng; González-González, Emilio; Burg, John S; Ataie, Niloufar J; Lam, Amy J; Cranfill, Paula J; Baird, Michelle A; Davidson, Michael W; Ng, Ho-Leung; Garcia, K Christopher; Contag, Christopher H; Shen, Kang; Blau, Helen M; Lin, Michael Z

    2014-01-01

    A method for non-invasive visualization of genetically labelled cells in animal disease models with micron-level resolution would greatly facilitate development of cell-based therapies. Imaging of fluorescent proteins (FPs) using red excitation light in the “optical window” above 600 nm is one potential method for visualizing implanted cells. However, previous efforts to engineer FPs with peak excitation beyond 600 nm have resulted in undesirable reductions in brightness. Here we report three new red-excitable monomeric FPs obtained by structure-guided mutagenesis of mNeptune, previously the brightest monomeric FP when excited beyond 600 nm. Two of these, mNeptune2 and mNeptune2.5, demonstrate improved maturation and brighter fluorescence, while the third, mCardinal, has a red-shifted excitation spectrum without reduction in brightness. We show that mCardinal can be used to non-invasively and longitudinally visualize the differentiation of myoblasts and stem cells into myocytes in living mice with high anatomical detail. PMID:24633408

  17. Non-Invasive Health Diagnostics using Eye as a 'Window to the Body'

    NASA Technical Reports Server (NTRS)

    Ansari, Rafat R.

    2002-01-01

    As a 'window to the body', the eye offers the opportunity to use light in various forms to detect ocular and systemic abnormalities long before clinical symptoms appear and help develop preventative/therapeutic countermeasures early. The effects of space travel on human body are similar to those of normal aging. For example, radiation exposure in space could lead to formation of cataracts and cancer by damaging the DNA and causing gene mutation. Additionally, the zero-gravity environment causes fluid shifts in the upper extremities of the body and changes the way blood flows and organ system performs. Here on Earth, cataract, age-related macular degeneration (AMD), diabetic retinopathy (DR), and glaucoma are major eye diseases and are expected to double in next two decades. To detect, prevent, and treat untoward effects of prolonged space travel in real-time requires the development of non-invasive diagnostic technologies that are compact and powerful. We are developing fiber-optic sensors to evaluate the ocular tissues in health, aging, and disease employing the techniques of dynamic light scattering (cataract, uveitis, Alzheimer's, glaucoma, DR, radiation damage, refractive surgery outcomes), auto-fluorescence (aging, DR), laser-Doppler flowmetry (choroidal blood flow), Raman spectroscopy (AMD), polarimetry (diabetes), and retinal oximetry (occult blood loss). The non-invasive feature of these technologies integrated in a head-mounted/goggles-like device permits frequent repetition of tests, enabling evaluation of the results to therapy that may ultimately be useful in various telemedicine applications on Earth and in space.

  18. Non-invasive methodology for diagnostics of bearing impacts

    NASA Astrophysics Data System (ADS)

    Chi, John N.

    2007-04-01

    Various events in reciprocating machinery, such as connecting rod or piston movement, and diesel combustion produce a series of highly transient forces within the machine. These events generate force transients of short duration and broad frequency content. Even though these events may be part of a machine cycle and therefore periodic, it is often more appropriate to treat them on an individual basis because more diagnostics information is available from a single waveform during a cycle than from averages over several cycles. However, it is very rare for one to have direct access to source waveforms because of the expense and reliability problems associated with the required instrumentation, and non-invasive techniques will have to be used. This paper explores the use of cepstral smoothing and minimum phase extraction technique for non-invasive diagnostics of bearing impacts in reciprocating machinery. The methodology is based on extracting diagnostic signals from vibration measurements taken at a "convenient" location such as the crankshaft casing or bearing end-cap, and consists of source identification, diagnostic signature recovery, and diagnostic system decision-making. A dynamic simulation with lumped mass model is developed to analyze bearing impacts for the big end bearings, experimental measurements from accelerometers, transfer functions of vibration, and the structural response are presented.

  19. Diagnosis and therapies for gastric non-invasive neoplasia

    PubMed Central

    Kato, Motohiko

    2015-01-01

    There has been a great discrepancy of pathological diagnosis for gastric non-invasive neoplasia/dysplasia between Japanese and western pathologists. In Japan, lesions that most western pathologists diagnose as dysplasia are often considered adenocarcinoma based on nuclear and structural atypia regardless of the presence of invasion. In the Vienna classification, gastric non-invasive intraepithelial neoplasia (NIN) were divided into low grade and high grade (including intra-mucosal cancer of Japanese criteria). The diagnosis by both endoscopy and pathology of biopsy specimen is difficult. Recent advances of diagnostic modality such as magnified endoscopy and imaged enhanced endoscopy is expected to improve the diagnostic yield for NIN. There are two treatment strategies for NIN, observation and diagnostic therapy by endoscopic resection (ER). ER is acceptable because of its less invasiveness and high local control rate, on the other hand, cancer-developing rate of low-grade NIN is reported to be low. Therefore there is controversy for the treatment of gastric NIN. Prospective study based on unified pathological definition is required in the future. PMID:26640329

  20. Use of Doppler ultrasound for non-invasive urodynamic diagnosis

    PubMed Central

    Ozawa, Hideo; Watanabe, Toyohiko; Uematsu, Katsutoshi; Sasaki, Katsumi; Inoue, Miyabi; Kumon, Hiromi

    2009-01-01

    Objectives: A totally non-invasive transperineal urodynamic technique using Doppler ultrasonography has been developed. Methods: Since normal urine does not have blood cells, urine was thought not to produce the Doppler effects. However, basic studies confirmed that the decrease of pressure at high velocity (Bernouilli effect) caused dissolved gas to form microbubbles, which are detected by Doppler ultrasonography. Subjects sat and the probe was advanced via remote control to achieve gentle contact with the perineal skin. The digital uroflow data signals and the color Doppler ultrasound video images were processed on a personal computer. The flow-velocity curves from two sites; the distal prostatic urethra just above the external sphincter (V1) and the sphincteric urethra (V2) were plotted against time. The parameters of both the pressure-flow studies and the Doppler ultrasound urodynamic studies were compared in men who had various degrees of obstruction. Results: Functional cross-sectional area at prostatic urethra (A1), calculated by Qmax/V1, was lower in the group of bladder outlet obstruction (BOO) vs. control group. Velocity ratio (VR), which was calculated by V1/V2, was the parameter having the best correlation with BOO index, though A1 had a similar correlation. This method is viable to diagnose the degree of BOO. Conclusions: The development of non-invasive Doppler ultrasound videourodynamics (Doppler UDS) will dramatically expand the information on voiding function. PMID:19468440

  1. Examination of postmortem retinal folds: A non-invasive study.

    PubMed

    Oshima, Toru; Yoshikawa, Hiroshi; Ohtani, Maki; Mimasaka, Sohtaro

    2015-02-01

    The postmortem retinal fold has been previously documented, but its mechanism of formation is not known. All previous studies of the fold involved invasive techniques and the postmortem ocular fundus has yet to be non-invasively examined. Our study used the non-invasive techniques of monocular indirect ophthalmoscopy and ocular echography to examine 79 postmortem eyes of 42 bodies. We examined whether the postmortem retinal fold was associated with postmortem time, position, and/or age. Age was significantly associated with postmortem retinal fold formation (Mann-Whitney U test, P = 0.013), which led us to examine the effect of posterior vitreous detachment (PVD) on retinal folds. The absence of a PVD was statistically associated with the presence of a retinal fold (Fisher's exact test, P < 0.0001). Interestingly, the presence of a PVD was also significantly correlated with retinal fold height (Mann-Whitney U test, P < 0.0001). Therefore, we hypothesized that retinal folds result from postmortem vitreoretinal traction caused by eyeball flaccidity. We also believe that the loss of retinochoroidal hydrostatic pressure plays a role. It is important that forensic pathologists not confuse a postmortem retinal fold with traumatic retinal detachment or perimacular retinal folds caused by child abuse. When child abuse is suspected, forensic pathologists should perform enucleation and a subsequent histological examination for confirmation. PMID:25623189

  2. Modulation of Untruthful Responses with Non-Invasive Brain Stimulation

    PubMed Central

    Fecteau, Shirley; Boggio, Paulo; Fregni, Felipe; Pascual-Leone, Alvaro

    2013-01-01

    Deceptive abilities have long been studied in relation to personality traits. More recently, studies explored the neural substrates associated with deceptive skills suggesting a critical role of the prefrontal cortex. Here we investigated whether non-invasive brain stimulation over the dorsolateral prefrontal cortex (DLPFC) could modulate generation of untruthful responses about subject’s personal life across contexts (i.e., deceiving on guilt-free questions on daily activities; generating previously memorized lies about past experience; and producing spontaneous lies about past experience), as well as across modality responses (verbal and motor responses). Results reveal that real, but not sham, transcranial direct current stimulation (tDCS) over the DLPFC can reduce response latency for untruthful over truthful answers across contexts and modality responses. Also, contexts of lies seem to incur a different hemispheric laterality. These findings add up to previous studies demonstrating that it is possible to modulate some processes involved in generation of untruthful answers by applying non-invasive brain stimulation over the DLPFC and extend these findings by showing a differential hemispheric contribution of DLPFCs according to contexts. PMID:23550273

  3. Non-invasive diagnosis of liver fibrosis and cirrhosis

    PubMed Central

    Lurie, Yoav; Webb, Muriel; Cytter-Kuint, Ruth; Shteingart, Shimon; Lederkremer, Gerardo Z

    2015-01-01

    The evaluation and follow up of liver fibrosis and cirrhosis have been traditionally performed by liver biopsy. However, during the last 20 years, it has become evident that this “gold-standard” is imperfect; even according to its proponents, it is only “the best” among available methods. Attempts at uncovering non-invasive diagnostic tools have yielded multiple scores, formulae, and imaging modalities. All are better tolerated, safer, more acceptable to the patient, and can be repeated essentially as often as required. Most are much less expensive than liver biopsy. Consequently, their use is growing, and in some countries the number of biopsies performed, at least for routine evaluation of hepatitis B and C, has declined sharply. However, the accuracy and diagnostic value of most, if not all, of these methods remains controversial. In this review for the practicing physician, we analyze established and novel biomarkers and physical techniques. We may be witnessing in recent years the beginning of the end of the first phase for the development of non-invasive markers. Early evidence suggests that they might be at least as good as liver biopsy. Novel experimental markers and imaging techniques could produce a dramatic change in diagnosis in the near future. PMID:26556987

  4. Non-invasive diagnostic imaging of colorectal liver metastases

    PubMed Central

    Mainenti, Pier Paolo; Romano, Federica; Pizzuti, Laura; Segreto, Sabrina; Storto, Giovanni; Mannelli, Lorenzo; Imbriaco, Massimo; Camera, Luigi; Maurea, Simone

    2015-01-01

    Colorectal cancer is one of the few malignant tumors in which synchronous or metachronous liver metastases [colorectal liver metastases (CRLMs)] may be treated with surgery. It has been demonstrated that resection of CRLMs improves the long-term prognosis. On the other hand, patients with un-resectable CRLMs may benefit from chemotherapy alone or in addition to liver-directed therapies. The choice of the most appropriate therapeutic management of CRLMs depends mostly on the diagnostic imaging. Nowadays, multiple non-invasive imaging modalities are available and those have a pivotal role in the workup of patients with CRLMs. Although extensive research has been performed with regards to the diagnostic performance of ultrasonography, computed tomography, positron emission tomography and magnetic resonance for the detection of CRLMs, the optimal imaging strategies for staging and follow up are still to be established. This largely due to the progressive technological and pharmacological advances which are constantly improving the accuracy of each imaging modality. This review describes the non-invasive imaging approaches of CRLMs reporting the technical features, the clinical indications, the advantages and the potential limitations of each modality, as well as including some information on the development of new imaging modalities, the role of new contrast media and the feasibility of using parametric image analysis as diagnostic marker of presence of CRLMs. PMID:26217455

  5. Characterization on Smart Optics Using Ellipsometry

    NASA Technical Reports Server (NTRS)

    Song, Kyo D.

    2002-01-01

    Recently, NASA Langley Research Center developed a smart active optical concept to filter narrow band pass or to control optical intensity. To characterize developed smart optics materials, we have measured thickness and reflection properties of the materials using a WVASE32 ellipsometry. This project allowed us to: (1) prepare the smart optical materials for measurement of thickness and optical properties at NASA Langley Research Center; (2) measure thickness and optical properties of the smart optical materials; (3) evaluate the measured properties in terms of applications for narrow band-pass filters. The outcomes of this research provide optical properties and physical properties of the smart optics on a selected spectral range. The applications of this development were used for field-controlled spectral smart filters.

  6. OCCIMA: Optical Channel Characterization in Maritime Atmospheres

    NASA Astrophysics Data System (ADS)

    Hammel, Steve; Tsintikidis, Dimitri; deGrassie, John; Reinhardt, Colin; McBryde, Kevin; Hallenborg, Eric; Wayne, David; Gibson, Kristofor; Cauble, Galen; Ascencio, Ana; Rudiger, Joshua

    2015-05-01

    The Navy is actively developing diverse optical application areas, including high-energy laser weapons and free- space optical communications, which depend on an accurate and timely knowledge of the state of the atmospheric channel. The Optical Channel Characterization in Maritime Atmospheres (OCCIMA) project is a comprehensive program to coalesce and extend the current capability to characterize the maritime atmosphere for all optical and infrared wavelengths. The program goal is the development of a unified and validated analysis toolbox. The foundational design for this program coordinates the development of sensors, measurement protocols, analytical models, and basic physics necessary to fulfill this goal.

  7. Chromatibody, a novel non-invasive molecular tool to explore and manipulate chromatin in living cells

    PubMed Central

    Jullien, Denis; Vignard, Julien; Fedor, Yoann; Béry, Nicolas; Olichon, Aurélien; Crozatier, Michèle; Erard, Monique; Cassard, Hervé; Ducommun, Bernard; Salles, Bernard

    2016-01-01

    ABSTRACT Chromatin function is involved in many cellular processes, its visualization or modification being essential in many developmental or cellular studies. Here, we present the characterization of chromatibody, a chromatin-binding single-domain, and explore its use in living cells. This non-intercalating tool specifically binds the heterodimer of H2A–H2B histones and displays a versatile reactivity, specifically labeling chromatin from yeast to mammals. We show that this genetically encoded probe, when fused to fluorescent proteins, allows non-invasive real-time chromatin imaging. Chromatibody is a dynamic chromatin probe that can be modulated. Finally, chromatibody is an efficient tool to target an enzymatic activity to the nucleosome, such as the DNA damage-dependent H2A ubiquitylation, which can modify this epigenetic mark at the scale of the genome and result in DNA damage signaling and repair defects. Taken together, these results identify chromatibody as a universal non-invasive tool for either in vivo chromatin imaging or to manipulate the chromatin landscape. PMID:27206857

  8. Development of non-invasive method for assessment of hepatic steatosis.

    PubMed

    Morikawa, H; Mano, K; Horinaka, H; Matsunaka, T; Matsumoto, Y; Ida, T; Kawaguchi, Y; Wada, K; Kawada, N

    2016-12-01

    Steatosis is a critical feature of liver disease and is considered to play a pivotal role in the progression of nonalcoholic fatty liver disease, as well as being a surrogate marker of metabolic syndrome. The purpose of this study was to develop a non-invasive diagnostic method for assessment of liver steatosis. It is well known that ultrasonic velocity depends on materials and temperature. For example, the ultrasonic velocity in water is 1530m/s at 37°C and 1534m/s at 39°C, while that in fat is 1412m/s at 37°C and 1402m/s at 39°C. On this basis, we thought that the percentage of fat in hepatic steatosis could be assessed by detecting changes of ultrasonic in the liver, caused by warming. In order to confirm the effectiveness of this method, we obtained the ultrasonic velocity changes of tissue phantom including lard oil and the liver of living rabbit by ultrasonic warming, and then succeeded in 2-D imaging of ultrasonic velocity changes of the phantom and the liver of living rabbit. We named this the ultrasonic velocity-change method. The experimental results show the possibility that hepatic steatosis could be characterized using our novel, non-invasive method. PMID:27567038

  9. A servo-mechanical load frame for in situ, non-invasive, imaging of damage development

    SciTech Connect

    Breunig, T.M.; Nichols, M.C.; Gruver, J.S.; Kinney, J.H.; Haupt, D.L.

    1993-12-31

    The X-ray tomographic microscope (XTM) is a non-invasive X-ray imaging instrument for characterizing a material`s structure three-dimensionally with microscopic spatial resolution. The authors have designed a servomechanical load frame for use with the XTM which will allow imaging of samples under load. The load frame is capable of generating tensile or compressive forces up to 15.6 kN with a design system stiffness of 8.76 {times} 10{sup 8} N/m. The test specimen can be rotated through 360{degree}, without induced bending or torque. Torqueless motion is accomplished by synchronously rotating the grips on precision bearings with an accuracy of 0.01{degree}. With this load frame it will be possible, for the first time, to image the initiation and accumulation of internal damage (0.5 {mu}m detectability) formed in a 6 mm diameter specimen during the application of a monotonic or low frequency cyclic load. This is accomplished by interrupting the test and maintaining a fixed load (or displacement) during the non-invasive XTM data collection procedure. This paper describes the in situ load frame design and experimental capabilities. This system can be used to enhance the understanding of failure in composite materials.

  10. Optical characterization in laser damage studies

    NASA Astrophysics Data System (ADS)

    Commandré, Mireille; Natoli, Jean Yves; Gallais, Laurent; Wagner, Frank; Amra, Claude

    2007-01-01

    The development of high power lasers and optical micro-components requires optical characterization techniques for studying behavior of optical materials under illumination, laser damage phenomena and ageing. More usual optical characterization tools are based on measurements of absorption, scattering and luminescence; they are non destructive evaluation techniques. It is important to combine several tools which allow getting complementary information. Optical tools can be used in damage initiation studies or to characterize properties of damaged areas. Because defects involved in laser damage initiation are sub-micrometer sized, both high spatial resolution and high sensitivity are required to detect defects as small as possible. Furthermore optical tools have to be implemented in damage set-up and at the same wavelength for a detailed analysis of damage mechanisms. We present an overview of recent developments in the field of optical characterization in connection with laser damage. Especially, a high resolution photothermal deflection microscopy has been coupled with a damage set-up to detect nano-absorbing precursors of damage and to study their behavior under irradiation. Thus model defects such as gold inclusions of various sizes have been followed through irradiation and results are compared with numerical simulations. Optical characterization allows to get determining information if several techniques are associated with numerical simulations.

  11. Using diffuse near-infrared light to characterize tissue optical and physiologic properties for medical diagnostics

    NASA Astrophysics Data System (ADS)

    Pham, Tuan Hoai

    2001-05-01

    Methods based on near-infrared (NIR) diffuse reflectance offer novel and functional approaches to medical diagnostics. NIR diffuse reflectance techniques are well suited for non-invasive, quantitative characterization of tissue optical properties, namely macroscopic absorption (μa) and reduced scattering (μs') coefficient. Tissue optical properties, in turn, provide unique and clinically relevant functional and structural information about tissues. Needless to say, understanding light- tissue interactions and light transport in multiply scattering (turbid) media is essential in order to fully capitalize on the useful features of NIR diffuse reflectance spectroscopy. This thesis addresses the practical and, to a limited extent, the theoretical issues of NIR diffuse light spectroscopy. The goals of the thesis are two folds: (1)to investigate, from an instrumental and analytical perspectives, the accuracy and limitation of the various diffuse reflectance techniques in quantifying the optical properties of homogenous and layered turbid media, and (2)to evaluate the feasibility and applicability of using NIR diffuse reflectance spectroscopy to quantify in vivo tissue optical and physiologic properties during pathophysiologic processes. With respect to the first objective, we conducted validation studies to assess the accuracy of the frequency-domain and spatially-resolved techniques in quantifying μa and μs' of homogenous turbid media. Similarly, frequency-domain and time-domain approaches were used to characterize the optical properties and thickness of two-layered turbid media. For the second objective, frequency-domain system was used to quantify the changes in the in vivo optical and physiologic properties secondary to cancerous transformation, cardiovascular dysfunction, and photodynamic therapy of tumors. In summary, studies results clearly indicate that NIR diffuse reflectance techniques accurately quantify the in vivo tissue optical and physiologic

  12. Non-invasive Chamber-Specific Identification of Cardiomyocytes in Differentiating Pluripotent Stem Cells

    PubMed Central

    Brauchle, Eva; Knopf, Anne; Bauer, Hannah; Shen, Nian; Linder, Sandra; Monaghan, Michael G.; Ellwanger, Kornelia; Layland, Shannon L.; Brucker, Sara Y.; Nsair, Ali; Schenke-Layland, Katja

    2016-01-01

    Summary One major obstacle to the application of stem cell-derived cardiomyocytes (CMs) for disease modeling and clinical therapies is the inability to identify the developmental stage of these cells without the need for genetic manipulation or utilization of exogenous markers. In this study, we demonstrate that Raman microspectroscopy can non-invasively identify embryonic stem cell (ESC)-derived chamber-specific CMs and monitor cell maturation. Using this marker-free approach, Raman peaks were identified for atrial and ventricular CMs, ESCs were successfully discriminated from their cardiac derivatives, a distinct phenotypic spectrum for ESC-derived CMs was confirmed, and unique spectral differences between fetal versus adult CMs were detected. The real-time identification and characterization of CMs, their progenitors, and subpopulations by Raman microspectroscopy strongly correlated to the phenotypical features of these cells. Due to its high molecular resolution, Raman microspectroscopy offers distinct analytical characterization for differentiating cardiovascular cell populations. PMID:26777059

  13. Non-invasive imaging of cellulose microfibril orientation within plant cell walls by polarized Raman microspectroscopy.

    PubMed

    Sun, Lan; Singh, Seema; Joo, Michael; Vega-Sanchez, Miguel; Ronald, Pamela; Simmons, Blake A; Adams, Paul; Auer, Manfred

    2016-01-01

    Cellulose microfibrils represent the major scaffold of plant cell walls. Different packing and orientation of the microfibrils at the microscopic scale determines the macroscopic properties of cell walls and thus affect their functions with a profound effect on plant survival. We developed a polarized Raman microspectroscopic method to determine cellulose microfibril orientation within rice plant cell walls. Employing an array of point measurements as well as area imaging and subsequent Matlab-assisted data processing, we were able to characterize the distribution of cellulose microfibril orientation in terms of director angle and anisotropy magnitude. Using this approach we detected differences between wild type rice plants and the rice brittle culm mutant, which shows a more disordered cellulose microfibril arrangement, and differences between different tissues of a wild type rice plant. This novel non-invasive Raman imaging approach allows for quantitative assessment of cellulose fiber orientation in cell walls of herbaceous plants, an important advancement in cell wall characterization. PMID:26137889

  14. Non-invasive imaging of microcirculation: a technology review

    PubMed Central

    Eriksson, Sam; Nilsson, Jan; Sturesson, Christian

    2014-01-01

    Microcirculation plays a crucial role in physiological processes of tissue oxygenation and nutritional exchange. Measurement of microcirculation can be applied on many organs in various pathologies. In this paper we aim to review the technique of non-invasive methods for imaging of the microcirculation. Methods covered are: videomicroscopy techniques, laser Doppler perfusion imaging, and laser speckle contrast imaging. Videomicroscopy techniques, such as orthogonal polarization spectral imaging and sidestream dark-field imaging, provide a plentitude of information and offer direct visualization of the microcirculation but have the major drawback that they may give pressure artifacts. Both laser Doppler perfusion imaging and laser speckle contrast imaging allow non-contact measurements but have the disadvantage of their sensitivity to motion artifacts and that they are confined to relative measurement comparisons. Ideal would be a non-contact videomicroscopy method with fully automatic analysis software. PMID:25525397

  15. [Non-invasive brain stimulation for Parkinson's disease].

    PubMed

    Gajo, Gianandrea; Pollak, Pierre; Lüscher, Christian; Benninger, David

    2015-04-29

    Parkinson's disease (PD) is a major socio-economic burden increasing with the aging population. In advanced PD, the emergence of symptoms refractory to conventional therapy poses a therapeutic challenge. The success of deep brain stimulation (DBS) and advances in the understanding of the pathophysiology of PD have raised interest in non-invasive brain stimulation (NIBS) as an alternative therapeutic tool. NIBS could offer an alternative approach for patients at risk who are excluded from surgery and/or to treat refractory symptoms. The treatment of the freezing of gait, a major cause of disability and falls in PD patients, could be enhanced by transcranial direct current stimulation (tDCS). A therapeutic study is currently performed at the Department of Neurology at the CHUV. PMID:26062225

  16. [Elemental research on intelligent non-invasive temporary pacemakers].

    PubMed

    Nie, Bang-ji; Xu, Long; Xin, Xue-gang; Wang, Cheng-lai; Wu, Min-shan

    2005-01-01

    Some research on intelligent non-invasive temporary pacemakers is introduced in this paper. An industrial computer, some IC chips and other elements are used to construct its hardware, and its software is in C++ language. The experimental device has some intelligent functions of recognizing some arrhythmia. The system has a pacemaker module and an ECG monitor module. Its software includes a main program, a RS-232C communication program, a printer VxD, a pacing control VxD and ECG signal pretreatment and recognizing program and so on. The pacing-generating circuit is employed to make the precision control of pacing current. The communication between industrial-computer system and ECG module is completed through the DLL. The real time processing of ECG signals is based on filter method for a higher recognizing ratio. The system calculates several parameters to recognize certain arrhythmia and uses MIT/BIH database to validate the reliability of ECG recognition. PMID:15875682

  17. [Non-invasive prenatal testing: challenges for future implementation].

    PubMed

    Henneman, Lidewij; Page-Chrisiaens, G C M L Lieve; Oepkes, Dick

    2015-01-01

    The non-invasive prenatal test (NIPT) is an accurate and safe test in which blood from the pregnant woman is used to investigate if the unborn child possibly has trisomy 21 (Down's syndrome), trisomy 18 (Edwards' syndrome) or trisomy 13 (Patau syndrome). Since April 2014 the NIPT has been available in the Netherlands as part of the TRIDENT implementation project for those in whom the first trimester combined test showed an elevated risk (> 1:200) of trisomy, or on medical indication, as an alternative to chorionic villous sampling or amniocentesis. Since the introduction of the NIPT the use of these invasive tests, which are associated with a risk of miscarriage, has fallen steeply. The NIPT may replace the combined test. Also the number of conditions that is tested for can be increased. Modification of current prenatal screening will require extensive discussion, but whatever the modification, careful counseling remains essential to facilitate pregnant women's autonomous reproductive decision making. PMID:26530119

  18. Non invasive sensing technologies for cultural heritage management and fruition

    NASA Astrophysics Data System (ADS)

    Soldovieri, Francesco; Masini, Nicola

    2016-04-01

    The relevance of the information produced by science and technology for the knowledge of the cultural heritage depends on the quality of the feedback and, consequently, on the "cultural" distance between scientists and end-users. In particular, the solution to this problem mainly resides in the capability of end-users' capability to assess and transform the knowledge produced by diagnostics with regard to: information on both cultural objects and sites (decay patterns, vulnerability, presence of buried archaeological remains); decision making (management plan, conservation project, and excavation plan). From our experience in the field of the cultural heritage and namely the conservation, of monuments, there is a significant gap of information between technologists (geophysicists/physicists/engineers) and end-users (conservators/historians/architects). This cultural gap is due to the difficulty to interpret "indirect data" produced by non invasive diagnostics (i.e. radargrams/thermal images/seismic tomography etc..) in order to provide information useful to improve the historical knowledge (e.g. the chronology of the different phases of a building), to characterise the state of conservation (e.g. detection of cracks in the masonry) and to monitor in time cultural heritage artifacts and sites. The possible answer to this difficulty is in the set-up of a knowledge chain regarding the following steps: - Integrated application of novel and robust data processing methods; - Augmented reality as a tool for making easier the interpretation of non invasive - investigations for the analysis of decay pathologies of masonry and architectural surfaces; - The comparison between direct data (carrots, visual inspection) and results from non-invasive tests, including geophysics, aims to improve the interpretation and the rendering of the monuments and even of the archaeological landscapes; - The use of specimens or test beds for the detection of archaeological features and

  19. Non-invasive Respiratory Support and Severe Retinopathy of Prematurity.

    PubMed

    Raghu, Rahul; Fisher, Marilyn; Cerone, Jennifer; Barry, Gerard

    2016-01-01

    The authors describe two premature infants who developed stage 3, zone I retinopathy of prematurity (ROP) with plus disease in both eyes, despite limited exposure to supra-ambient oxygen. Both infants received noninvasive respiratory support for several weeks. Both cases are notable because the ROP was more posterior and aggressive than is typical for the gestational ages or birth weights. These cases are insufficient to make definitive conclusions regarding the factors that cause ROP. Further investigation is required to determine if there is an association between the use of non-invasive respiratory support, even in the absence of supra-ambient oxygen, and severe ROP development. [J Pediatr Ophthalmol Strabismus. 2016;53:e47-e50.]. PMID:27537495

  20. Eyeblink conditioning: a non-invasive biomarker for neurodevelopmental disorders.

    PubMed

    Reeb-Sutherland, Bethany C; Fox, Nathan A

    2015-02-01

    Eyeblink conditioning (EBC) is a classical conditioning paradigm typically used to study the underlying neural processes of learning and memory. EBC has a well-defined neural circuitry, is non-invasive, and can be employed in human infants shortly after birth making it an ideal tool to use in both developing and special populations. In addition, abnormalities in the cerebellum, a region of the brain highly involved in EBC, have been implicated in a number of neurodevelopmental disorders including autism spectrum disorders (ASDs). In the current paper, we review studies that have employed EBC as a biomarker for several neurodevelopmental disorders including fetal alcohol syndrome, Down syndrome, fragile X syndrome, attention deficit/hyperactivity disorder, dyslexia, specific language impairment, and schizophrenia. In addition, we discuss the benefits of using such a tool in individuals with ASD. PMID:23942847

  1. Non-invasive ventilation in exacerbations of COPD

    PubMed Central

    Ambrosino, Nicolino; Vagheggini, Guido

    2007-01-01

    Randomized controlled trials have confirmed the evidence and helped to define when and where non invasive mechanical ventilation (NIV) should be the first line treatment of acute exacerbations of chronic obstructive pulmonary disease (AECOPD). Noninvasive ventilation has its best indication in moderate-to-severe respiratory acidosis in patients with AECOPD. For this indication, studies conducted in ICU, in wards and in accident and emergency departments confirmed its effectiveness in preventing endotracheal intubation and reducing mortality. The skill of the health care team promotes proper NIV utilization and improves the patient outcome. Patients with severe acidosis or with altered levels of consciousness due to hypercapnic acute respiratory failure are exposed to high risk of NIV failure. In these patients a NIV trial may be attempted in closely monitored clinical settings where prompt endotracheal intubation may be assured. PMID:18268921

  2. Non-invasive Loading Model of Murine Osteoarthritis.

    PubMed

    Poulet, Blandine

    2016-07-01

    Osteoarthritis is the commonest degenerative joint disease, leading to joint pain and disability. The mouse has been the primary animal used for research, due to its size, relatively short lifespan, and the availability of genetically modified animals. Importantly, they show pathogenesis similar to osteoarthritis in humans. Mechanical loading is a major risk factor for osteoarthritis, and various mouse models have been developed to study the role and effects of mechanics on health and disease in various joints. This review describes the main mouse models used to non-invasively apply mechanical loads on joints. Most of the mouse models of osteoarthritis target the knee, including repetitive loading and joint injury such as ligament rupture, but a few studies have also characterised models for elbow, temporomandibular joint, and whole-body vibration spinal loading. These models are a great opportunity to dissect the influences of various types of mechanical input on joint health and disease. PMID:27177901

  3. Non-invasive measurments of intense relativistic electron beam size

    NASA Astrophysics Data System (ADS)

    Ekdahl, Carl; McCuistian, Trent; Moir, David; Rodriguez, Patrick; Broste, William; Johnson, Jeff

    2000-10-01

    To understand relativistic electron beam transport dynamics the size of the beam is often measured using invasive techniques such as imaging the Cerenkov or OTR light emitted from a screen inserted into the beam. These techniques would completely disrupt the DARHT 2 beam, so we are developing a non-invasive method using diamagnetic loops. We show that through conservation of canonical angular momentum the RMS radius of the beam can be found by measuring the magnetic flux excluded by the diamagnetic beam. Furthermore, this measurement is shown to be independent of the details of the beam radial current profile for DARHT 2 parameters. We present results from our test and calibration experiments, as well as results of beam radius measurements on the 20-MeV DARHT 1 accelerator.

  4. Non-invasive assessment of skeletal muscle activity

    NASA Astrophysics Data System (ADS)

    Merletti, Roberto; Orizio, Claudio; di Prampero, Pietro E.; Tesch, Per

    2005-10-01

    After the first 3 years (2002-2005), the MAP project has made available: - systems fo electrodes, signal conditioning and digital processing for multichannel simultaneously-detected EMG and MMG as well as for simultaneous electrical stimulation and EMG detection with artifact cancellation. - innovative non-invasive techniques for the extraction of individual motor unit action potentials (MUAPS) and individual motor and MMG contributions from the surface EMG interference signal and the MMG signal. - processing techniques for extractions of indicators of progressive fatigue from the electrically-elicited (M-wave) EMG signal. - techniques for the analysis of dynamic multichannel EMG during cyclic or explosive exercise (in collaboration with project EXER/MAP-MED-027).

  5. Continuous non-invasive finger blood pressure monitoring in children.

    PubMed

    Tanaka, H; Thulesius, O; Yamaguchi, H; Mino, M; Konishi, K

    1994-06-01

    We evaluated the performance of continuous non-invasive finger arterial pressure measurement using the volume-clamp technique (Finapres). This study was designed to compare finger arterial pressure with brachial blood pressure estimated by the auscultatory method in 217 children (90 boys and 127 girls) aged 4-16 years and in 38 adults (aged 18-45 years). Finger and brachial artery pressure readings were obtained consecutively from the ipsilateral side in the supine position. Finger arterial pressure waveforms were recorded in all children except 4 with small and thin fingers. There was good agreement for systolic pressure with only a slight underestimation of 1.9 mmHg and 5.1 mmHg lower for diastolic pressure. This difference most probably reflects inaccuracy of the auscultatory cuff method rather than an error in the Finapres. There was large inter-individual variability in Finapres recordings which might be due to differences in vasomotor tone, as demonstrated by systolic amplification in 5 patients with anorexia. However, Finapres showed a small within-subject variability (3.8 mmHg for systolic and 4.1 mmHg for diastolic pressure) determined in 5 patients during phenylephrine infusion, and as good reproducibility as the auscultatory method. These results suggest that finger arterial pressure measurement in children older than 6 years of age has similar accuracy as that in adults, and that this method is useful for clinical applications in children, especially for the non-invasive evaluation of autonomic control and cardiovascular reflexes involving transient and rapid blood pressure changes. PMID:7919764

  6. It Takes Two: Non Invasive Brain Stimulation Combined with Neurorehabilitation

    PubMed Central

    Page, Stephen J.; Cunningham, David A; Plow, Ela; Blazak, Brittani

    2015-01-01

    The goal of post-acute neurorehabilitation is to maximize patients' function, ideally by using surviving brain and central nervous system tissue when possible. Yet the structures incorporated into neurorehabilitative approaches often differ from this target, which may explain why efficacy of conventional clinical treatments targeting neurological impairments varies widely. Non-invasive brain stimulation such as with Transcranial Magnetic Stimulation (TMS) and transcranial direct current stimulation (tDCS) offers the possibility of directly targeting brain structures to facilitate or inhibit their activity so as to steer neural plasticity in recovery, and measure neuronal output and interactions for evaluating progress. Latest advances as stereotactic navigation and electric field modeling are enabling more precise targeting of patient's residual structures in diagnosis and therapy. Given its promise, this supplement illustrates the wide-ranging significance of TMS and tDCS in neurorehabilitation, including in stroke, pediatrics, traumatic brain injury, focal hand dystonia, neuropathic pain and spinal cord injury. TMS and tDCS are still not widely used and remain poorly understood in neurorehabilitation. Thus, the present supplement includes articles that highlight ready clinical application of these technologies, including their comparative diagnostic capabilities relative to neuroimaging, their therapeutic benefit, their optimal delivery, the stratification of likely responders, and the variable benefits associated with their clinical use due to interactions between pathophysiology and the innate reorganization of the patient's brain. Overall, the supplement concludes that whether provided in isolation or in combination, non-invasive brain stimulation with neuro-rehabilitation are synergistic in the potential to transform clinical practice. PMID:25813373

  7. Non-invasive assessment of microvascular and endothelial function.

    PubMed

    Cheng, Cynthia; Daskalakis, Constantine; Falkner, Bonita

    2013-01-01

    The authors have utilized capillaroscopy and forearm blood flow techniques to investigate the role of microvascular dysfunction in pathogenesis of cardiovascular disease. Capillaroscopy is a non-invasive, relatively inexpensive methodology for directly visualizing the microcirculation. Percent capillary recruitment is assessed by dividing the increase in capillary density induced by postocclusive reactive hyperemia (postocclusive reactive hyperemia capillary density minus baseline capillary density), by the maximal capillary density (observed during passive venous occlusion). Percent perfused capillaries represents the proportion of all capillaries present that are perfused (functionally active), and is calculated by dividing postocclusive reactive hyperemia capillary density by the maximal capillary density. Both percent capillary recruitment and percent perfused capillaries reflect the number of functional capillaries. The forearm blood flow (FBF) technique provides accepted non-invasive measures of endothelial function: The ratio FBF(max)/FBF(base) is computed as an estimate of vasodilation, by dividing the mean of the four FBF(max) values by the mean of the four FBFbase values. Forearm vascular resistance at maximal vasodilation (FVR(max)) is calculated as the mean arterial pressure (MAP) divided by FBF(max). Both the capillaroscopy and forearm techniques are readily acceptable to patients and can be learned quickly. The microvascular and endothelial function measures obtained using the methodologies described in this paper may have future utility in clinical patient cardiovascular risk-reduction strategies. As we have published reports demonstrating that microvascular and endothelial dysfunction are found in initial stages of hypertension including prehypertension, microvascular and endothelial function measures may eventually aid in early identification, risk-stratification and prevention of end-stage vascular pathology, with its potentially fatal

  8. Non-invasive diagnosis of alcoholic liver disease.

    PubMed

    Mueller, Sebastian; Seitz, Helmut Karl; Rausch, Vanessa

    2014-10-28

    Alcoholic liver disease (ALD) is the most common liver disease in the Western world. For many reasons, it is underestimated and underdiagnosed. An early diagnosis is absolutely essential since it (1) helps to identify patients at genetic risk for ALD; (2) can trigger efficient abstinence namely in non-addicted patients; and (3) initiate screening programs to prevent life-threatening complications such as bleeding from varices, spontaneous bacterial peritonitis or hepatocellular cancer. The two major end points of ALD are alcoholic liver cirrhosis and the rare and clinically-defined alcoholic hepatitis (AH). The prediction and early diagnosis of both entities is still insufficiently solved and usually relies on a combination of laboratory, clinical and imaging findings. It is not widely conceived that conventional screening tools for ALD such as ultrasound imaging or routine laboratory testing can easily overlook ca. 40% of manifest alcoholic liver cirrhosis. Non-invasive methods such as transient elastography (Fibroscan), acoustic radiation force impulse imaging or shear wave elastography have significantly improved the early diagnosis of alcoholic cirrhosis. Present algorithms allow either the exclusion or the exact definition of advanced fibrosis stages in ca. 95% of patients. The correct interpretation of liver stiffness requires a timely abdominal ultrasound and actual transaminase levels. Other non-invasive methods such as controlled attenuation parameter, serum levels of M30 or M65, susceptometry or breath tests are under current evaluation to assess the degree of steatosis, apoptosis and iron overload in these patients. Liver biopsy still remains an important option to rule out comorbidities and to confirm the prognosis namely for patients with AH. PMID:25356026

  9. Non-invasive diagnosis of alcoholic liver disease

    PubMed Central

    Mueller, Sebastian; Seitz, Helmut Karl; Rausch, Vanessa

    2014-01-01

    Alcoholic liver disease (ALD) is the most common liver disease in the Western world. For many reasons, it is underestimated and underdiagnosed. An early diagnosis is absolutely essential since it (1) helps to identify patients at genetic risk for ALD; (2) can trigger efficient abstinence namely in non-addicted patients; and (3) initiate screening programs to prevent life-threatening complications such as bleeding from varices, spontaneous bacterial peritonitis or hepatocellular cancer. The two major end points of ALD are alcoholic liver cirrhosis and the rare and clinically-defined alcoholic hepatitis (AH). The prediction and early diagnosis of both entities is still insufficiently solved and usually relies on a combination of laboratory, clinical and imaging findings. It is not widely conceived that conventional screening tools for ALD such as ultrasound imaging or routine laboratory testing can easily overlook ca. 40% of manifest alcoholic liver cirrhosis. Non-invasive methods such as transient elastography (Fibroscan), acoustic radiation force impulse imaging or shear wave elastography have significantly improved the early diagnosis of alcoholic cirrhosis. Present algorithms allow either the exclusion or the exact definition of advanced fibrosis stages in ca. 95% of patients. The correct interpretation of liver stiffness requires a timely abdominal ultrasound and actual transaminase levels. Other non-invasive methods such as controlled attenuation parameter, serum levels of M30 or M65, susceptometry or breath tests are under current evaluation to assess the degree of steatosis, apoptosis and iron overload in these patients. Liver biopsy still remains an important option to rule out comorbidities and to confirm the prognosis namely for patients with AH. PMID:25356026

  10. Novel non invasive diagnostic strategies in bladder cancer

    PubMed Central

    TRUTA, ANAMARIA; POPON, TUDOR ADRIAN HODOR; SARACI, GEORGE; GHERVAN, LIVIU; POP, IOAN VICTOR

    2016-01-01

    Bladder cancer is one of the most commonly diagnosed malignancies worldwide, derived from the urothelium of the urinary bladder and defined by long asymptomatic and atypical clinical picture. Its complex etiopathogenesis is dependent on numerous risk factors that can be divided into three distinct categories: genetic and molecular abnormalities, chemical or environmental exposure and previous genitourinary disorders and family history of different malignancies. Various genetic polymorphisms and microRNA might represent useful diagnostic or prognostic biomarkers. Genetic and molecular abnormalities - risk factors are represented by miRNA or genetic polymorphisms proved to be part of bladder carcinogenesis such as: genetic mutations of oncogenes TP53, Ras, Rb1 or p21 oncoproteins, cyclin D or genetic polymorhisms of XPD,ERCC1, CYP1B1, NQO1C609T, MDM2SNP309, CHEK2, ERCC6, NRF2, NQO1Pro187Ser polymorphism and microRNA (miR-143, −145, −222, −210, −10b, 576-3p). The aim of our article is to highlight the most recent acquisitions via molecular biomarkers (miRNAs and genetic polymorphisms) involved in bladder cancer in order to provide early diagnosis, precise therapy according to the molecular profile of bladder tumors, as well as to improve clinical outcome, survival rates and life quality of oncological patients. These molecular biomarkers play a key role in bladder carcinogenesis, clinical evolution, prognosis and therapeutic response and explain the molecular mechanisms involved in bladder carcinogenesis; they can also be selected as therapeutic targets in developing novel therapeutic strategies in bladder malignancies. Moreover, the purpose in defining these molecular non invasive biomarkers is also to develop non invasive screening programs in bladder malignancies with the result of decreasing bladder cancer incidence in risk population. PMID:27152066

  11. Application of fluorescence spectroscopy and multispectral imaging for non-invasive estimation of GFP transfection efficiency

    NASA Astrophysics Data System (ADS)

    Tamošiūnas, M.; Jakovels, D.; Lihačovs, A.; Kilikevičius, A.; Baltušnikas, J.; Kadikis, R.; Šatkauskas, S.

    2014-10-01

    Electroporation and ultrasound induced sonoporation has been showed to induce plasmid DNA transfection to the mice tibialis cranialis muscle. It offers new prospects for gene therapy and cancer treatment. However, numerous experimental data are still needed to deliver the plausible explanation of the mechanisms governing DNA electro- or sono-transfection, as well as to provide the updates on transfection protocols for transfection efficiency increase. In this study we aimed to apply non-invasive optical diagnostic methods for the real time evaluation of GFP transfection levels at the reduced costs for experimental apparatus and animal consumption. Our experimental set-up allowed monitoring of GFP levels in live mice tibialis cranialis muscle and provided the parameters for DNA transfection efficiency determination.

  12. Monte Carlo simulation of non-invasive glucose measurement based on FMCW LIDAR

    NASA Astrophysics Data System (ADS)

    Xiong, Bing; Wei, Wenxiong; Liu, Nan; He, Jian-Jun

    2010-11-01

    Continuous non-invasive glucose monitoring is a powerful tool for the treatment and management of diabetes. A glucose measurement method, with the potential advantage of miniaturizability with no moving parts, based on the frequency modulated continuous wave (FMCW) LIDAR technology is proposed and investigated. The system mainly consists of an integrated near-infrared tunable semiconductor laser and a detector, using heterodyne technology to convert the signal from time-domain to frequency-domain. To investigate the feasibility of the method, Monte Carlo simulations have been performed on tissue phantoms with optical parameters similar to those of human interstitial fluid. The simulation showed that the sensitivity of the FMCW LIDAR system to glucose concentration can reach 0.2mM. Our analysis suggests that the FMCW LIDAR technique has good potential for noninvasive blood glucose monitoring.

  13. Non-invasive sex assessment in bovine semen by Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    De Luca, A. C.; Managó, S.; Ferrara, M. A.; Rendina, I.; Sirleto, L.; Puglisi, R.; Balduzzi, D.; Galli, A.; Ferraro, P.; Coppola, G.

    2014-05-01

    X- and Y-chromosome-bearing sperm cell sorting is of great interest, especially for animal production management systems and genetic improvement programs. Here, we demonstrate an optical method based on Raman spectroscopy to separate X- and Y-chromosome-bearing sperm cells, overcoming many of the limitations associated with current sex-sorting protocols. A priori Raman imaging of bull spermatozoa was utilized to select the sampling points (head-neck region), which were then used to discriminate cells based on a spectral classification model. Main variations of Raman peaks associated with the DNA content were observed together with a variation due to the sex membrane proteins. Next, we used principal component analysis to determine the efficiency of our device as a cell sorting method. The results (>90% accuracy) demonstrated that Raman spectroscopy is a powerful candidate for the development of a highly efficient, non-invasive, and non-destructive tool for sperm sexing.

  14. Non-invasive blood glucose monitoring with Raman spectroscopy: prospects for device miniaturization

    NASA Astrophysics Data System (ADS)

    Wróbel, M. S.

    2016-01-01

    The number of patients with diabetes has reached over 350 million, and still continues to increase. The need for regular blood glucose monitoring sparks the interest in the development of modern detection technologies. One of those methods, which allows for noninvasive measurements, is Raman spectroscopy. The ability of infrared light to penetrate deep into tissues allows for obtaining measurements through the skin without its perforation. This paper presents the limitations and possibilities of non-invasive blood glucose monitoring with Raman spectroscopy. Especially focusing on the possibilities for device miniaturization. Such device incorporates a Raman spectrometer, a fiber-optical probe, and a computing device (microcontroller, smartphone, etc.) which calculates the glucose concentration using specialized algorithms. Simplification of device design, as well as turbidity correction technique and a new proposed method of synchronized detection are described.

  15. Quantitative non-invasive intracellular imaging of Plasmodium falciparum infected human erythrocytes

    NASA Astrophysics Data System (ADS)

    Edward, Kert; Farahi, Faramarz

    2014-05-01

    Malaria is a virulent pathological condition which results in over a million annual deaths. The parasitic agent Plasmodium falciparum has been extensively studied in connection with this epidemic but much remains unknown about its development inside the red blood cell host. Optical and fluorescence imaging are among the two most common procedures for investigating infected erythrocytes but both require the introduction of exogenous contrast agents. In this letter, we present a procedure for the non-invasive in situ imaging of malaria infected red blood cells. The procedure is based on the utilization of simultaneously acquired quantitative phase and independent topography data to extract intracellular information. Our method allows for the identification of the developmental stages of the parasite and facilitates in situ analysis of the morphological changes associated with the progression of this disease. This information may assist in the development of efficacious treatment therapies for this condition.

  16. Development of a non-invasive LED based device for adipose tissue thickness measurements in vivo

    NASA Astrophysics Data System (ADS)

    Volceka, K.; Jakovels, D.; Arina, Z.; Zaharans, J.; Kviesis, E.; Strode, A.; Svampe, E.; Ozolina-Moll, L.; Butnere, M. M.

    2012-06-01

    There are a number of techniques for body composition assessment in clinics and in field-surveys, but in all cases the applied methods have advantages and disadvantages. High precision imaging methods are available, though expensive and non-portable, however, the methods devised for the mass population, often suffer from the lack of precision. Therefore, the development of a safe, mobile, non-invasive, optical method that would be easy to perform, precise and low-cost, but also would offer an accurate assessment of subcutaneous adipose tissue (SAT) both in lean and in obese persons is required. Thereof, the diffuse optical spectroscopy is advantageous over the aforementioned techniques. A prototype device using an optical method for measurement of the SAT thickness in vivo has been developed. The probe contained multiple LEDs (660nm) distributed at various distances from the photo-detector which allow different light penetration depths into the subcutaneous tissue. The differences of the reflected light intensities were used to create a non-linear model, and the computed values were compared with the corresponding thicknesses of SAT, assessed by B-mode ultrasonography. The results show that with the optical system used in this study, accurate results of different SAT thicknesses can be obtained, and imply a further potential for development of multispectral optical system to observe changes of SAT thickness as well as to determine the percentage of total body fat.

  17. A New Quantitative Method for the Non-Invasive Documentation of Morphological Damage in Paintings Using RTI Surface Normals

    PubMed Central

    Manfredi, Marcello; Bearman, Greg; Williamson, Greg; Kronkright, Dale; Doehne, Eric; Jacobs, Megan; Marengo, Emilio

    2014-01-01

    In this paper we propose a reliable surface imaging method for the non-invasive detection of morphological changes in paintings. Usually, the evaluation and quantification of changes and defects results mostly from an optical and subjective assessment, through the comparison of the previous and subsequent state of conservation and by means of condition reports. Using quantitative Reflectance Transformation Imaging (RTI) we obtain detailed information on the geometry and morphology of the painting surface with a fast, precise and non-invasive method. Accurate and quantitative measurements of deterioration were acquired after the painting experienced artificial damage. Morphological changes were documented using normal vector images while the intensity map succeeded in highlighting, quantifying and describing the physical changes. We estimate that the technique can detect a morphological damage slightly smaller than 0.3 mm, which would be difficult to detect with the eye, considering the painting size. This non-invasive tool could be very useful, for example, to examine paintings and artwork before they travel on loan or during a restoration. The method lends itself to automated analysis of large images and datasets. Quantitative RTI thus eases the transition of extending human vision into the realm of measuring change over time. PMID:25010699

  18. Characterizing conical refraction optical tweezers.

    PubMed

    McDonald, C; McDougall, C; Rafailov, E; McGloin, D

    2014-12-01

    Conical refraction occurs when a beam of light travels through an appropriately cut biaxial crystal. By focusing the conically refracted beam through a high numerical aperture microscope objective, conical refraction optical tweezers can be created, allowing for particle manipulation in both Raman spots, and in the Lloyd/Poggendorff rings. We present a thorough quantification of the trapping properties of such a beam, focusing on the trap stiffness, and how this varies with trap power and trapped particle location. We show that the lower Raman spot can be thought of as a single-beam optical gradient force trap, while radiation pressure dominates in the upper Raman spot, leading to optical levitation rather than trapping. Particles in the Lloyd/Poggendorff rings experience a lower trap stiffness than particles in the lower Raman spot, but benefit from rotational control. PMID:25490654

  19. Optical fiber dispersion characterization study

    NASA Technical Reports Server (NTRS)

    Geeslin, A.; Arriad, A.; Riad, S. M.; Padgett, M. E.

    1979-01-01

    The theory, design, and results of optical fiber pulse dispersion measurements are considered. Both the hardware and software required to perform this type of measurement are described. Hardware includes a thermoelectrically cooled injection laser diode source, an 800 GHz gain bandwidth produce avalanche photodiode and an input mode scrambler. Software for a HP 9825 computer includes fast Fourier transform, inverse Fourier transform, and optimal compensation deconvolution. Test set construction details are also included. Test results include data collected on a 1 Km fiber, a 4 Km fiber, a fused spliced, eight 600 meter length fibers concatenated to form 4.8 Km, and up to nine optical connectors.

  20. Non-invasive hyperthermia apparatus including coaxial applicator having a non-invasive radiometric receiving antenna incorporated therein and method of use thereof

    DOEpatents

    Ross, Michael P.

    1996-01-01

    A coaxial hyperthermia applicator for applying non-invasively electromagnetic energy to a body against which it is placed. The coaxial applicator antenna has formed integrally within it a non-invasive radiometric antenna for receiving thermoelectromagnetic emissions. The coaxial-configured applicator produces a bell-shaped radiation pattern symmetric about the axis of symmetry of the coaxial applicator. Integrating the radiometric antenna within the coaxial applicator produces a single device that performs dual functions. The first function is to transmit non-invasively energy for heating a subcutaneous tumor. The second function is to receive non-invasively thermal electromagnetic radiation from the tumor by which temperature is sensed and fed back to control the output of the coaxial applicator.

  1. Non-invasive hyperthermia apparatus including coaxial applicator having a non-invasive radiometric receiving antenna incorporated therein and method of use thereof

    DOEpatents

    Ross, M.P.

    1996-08-27

    A coaxial hyperthermia applicator is disclosed for applying non-invasively electromagnetic energy to a body against which it is placed. The coaxial applicator antenna has formed integrally within it a non-invasive radiometric antenna for receiving thermoelectromagnetic emissions. The coaxial-configured applicator produces a bell-shaped radiation pattern symmetric about the axis of symmetry of the coaxial applicator. Integrating the radiometric antenna within the coaxial applicator produces a single device that performs dual functions. The first function is to transmit non-invasively energy for heating a subcutaneous tumor. The second function is to receive non-invasively thermal electromagnetic radiation from the tumor by which temperature is sensed and fed back to control the output of the coaxial applicator. 11 figs.

  2. A holistic multimodal approach to the non-invasive analysis of watercolour paintings

    NASA Astrophysics Data System (ADS)

    Kogou, Sotiria; Lucian, Andrei; Bellesia, Sonia; Burgio, Lucia; Bailey, Kate; Brooks, Charlotte; Liang, Haida

    2015-11-01

    A holistic approach using non-invasive multimodal imaging and spectroscopic techniques to study the materials (pigments, drawing materials and paper) and painting techniques of watercolour paintings is presented. The non-invasive imaging and spectroscopic techniques include VIS-NIR reflectance spectroscopy and multispectral imaging, micro-Raman spectroscopy, X-ray fluorescence spectroscopy (XRF) and optical coherence tomography (OCT). The three spectroscopic techniques complement each other in pigment identification. Multispectral imaging (near-infrared bands), OCT and micro-Raman complement each other in the visualisation and identification of the drawing material. OCT probes the micro-structure and light scattering properties of the substrate, while XRF detects the elemental composition that indicates the sizing methods and the filler content. The multiple techniques were applied in a study of forty-six nineteenth-century Chinese export watercolours from the Victoria and Albert Museum (V&A) and the Royal Horticultural Society (RHS) to examine to what extent the non-invasive analysis techniques employed complement each other and how much useful information about the paintings can be extracted to address art conservation and history questions. A micro-destructive technique of micro-fade spectrometry was used to assess the vulnerability of the paintings to light exposure. Most of the paint and paper substrates were found to be more stable than ISO Blue Wool 3. The palette was found to be composed of mostly traditional Chinese pigments. While the synthetic pigment, Prussian blue, made in Europe, was found on some of the paintings, none was found on the RHS paintings accurately recorded as being between 1817 and 1831 even though it is known that Prussian blue was imported to China during this period. The scale insect dyes, lac and cochineal, were detected on nearly every painting including those that fall within the identified date range. Cochineal is known to have

  3. Non-invasive assessment of portal hypertension and liver fibrosis using contrast-enhanced ultrasonography.

    PubMed

    Maruyama, Hitoshi; Shiha, Gamal; Yokosuka, Osamu; Kumar, Ashish; Sharma, Barjesh Chander; Ibrahim, Alaa; Saraswat, Vivek; Lesmana, Cosmas Rinaldi A; Omata, Masao

    2016-03-01

    Portal hypertension and hepatic fibrosis are key pathophysiologies with major manifestations in cirrhosis. Although the degree of portal pressure and hepatic fibrosis are pivotal parameters, both are determined using invasive procedures. Ultrasound (US) is a simple and non-invasive technique that is available for use worldwide in the abdominal field. Because of its safety and easy of use, contrast-enhanced US is one of the most frequently used tools in the management of liver tumors for the detection and characterization of lesions, assessment of malignancy grade, and evaluation of therapeutic effects. This wide range of applications drives the practical use of contrast-enhanced US for evaluation of the severity of portal hypertension and hepatic fibrosis. The present article reviews the recent progress in contrast-enhanced US for the assessment of portal hypertension and hepatic fibrosis. PMID:26696585

  4. [Amyotrophic neuralgia associated with bilateral phrenic paralysis treated with non-invasive mechanical ventilation].

    PubMed

    García García, María Del Carmen; Hernández Borge, Jacinto; Antona Rodríguez, María José; Pires Gonçalves, Pedro; García García, Gema

    2015-09-01

    Amyotrophic neuralgia is an uncommon neuropathy characterized by severe unilateral shoulder pain. Isolated or concomitant involvement of other peripheral motor nerves depending on the brachial plexus such as phrenic or laryngeal nerves is unusual(1). Its etiology is unknown, yet several explanatory factors have been proposed. Phrenic nerve involvement, either unilateral or bilateral, is exceedingly rare. Diagnosis relies on anamnesis, functional and imaging investigations and electromyogram. We report the case of a 48-year-old woman with a past history of renal transplantation due to proliferative glomerulonephritis with subsequent transplant rejection, who was eventually diagnosed with amyotrophic neuralgia with bilateral phrenic involvement, and who required sustained non-invasive mechanical ventilation. PMID:26049960

  5. State of the Art: Neonatal Non-invasive Respiratory Support: Physiological Implications

    PubMed Central

    Shaffer, Thomas H.; Alapati, Deepthi; Greenspan, Jay S.; Wolfson, Marla R.

    2013-01-01

    Summary The introduction of assisted ventilation for neonatal pulmonary insufficiency has resulted in the successful treatment of many previously fatal diseases. During the past three decades, refinement of invasive mechanical ventilation techniques has dramatically improved survival of many high-risk neonates. However, as with many advances in medicine, while mortality has been reduced, morbidity has increased in the surviving high-risk neonate. In this regard, introduction of assisted ventilation has been associated with chronic lung injury, also known as bronchopulmonary dysplasia. This disease, unknown prior to the appearance of mechanical ventilation, has produced a population of patients characterized by ventilator or oxygen dependence with serious accompanying pulmonary and neurodevelopmental morbidity. The purpose of this article is to review non-invasive respiratory support methodologies to address the physiologic mechanisms by which these methods may prevent the pathophysiologic effects of invasive mechanical ventilation. PMID:22777738

  6. Insights into Parkinson's disease models and neurotoxicity using non-invasive imaging

    SciTech Connect

    Sanchez-Pernaute, Rosario; Jenkins, Bruce G.; Isacson, Ole

    2005-09-01

    Loss of dopamine in the nigrostriatal system causes a severe impairment in motor function in patients with Parkinson's disease and in experimental neurotoxic models of the disease. We have used non-invasive imaging techniques such as positron emission tomography (PET) and functional magnetic resonance imaging (MRI) to investigate in vivo the changes in the dopamine system in neurotoxic models of Parkinson's disease. In addition to classic neurotransmitter studies, in these models, it is also possible to characterize associated and perhaps pathogenic factors, such as the contribution of microglia activation and inflammatory responses to neuronal damage. Functional imaging techniques are instrumental to our understanding and modeling of disease mechanisms, which should in turn lead to development of new therapies for Parkinson's disease and other neurodegenerative disorders.

  7. Non-invasive imaging of flow and vascular function in disease of the aorta

    PubMed Central

    Whitlock, Matthew C.; Hundley, W. Gregory

    2015-01-01

    With advancements in technology and a better understanding of human cardiovascular physiology, research as well as clinical care can go beyond dimensional anatomy offered by traditional imaging and investigate aortic functional properties and the impact disease has on this function. Linking the knowledge of the histopathological changes with the alterations in aortic function observed on noninvasive imaging results in a better understanding of disease pathophysiology. Translating this to clinical medicine, these noninvasive imaging assessments of aortic function are proving to be able to diagnosis disease, better predict risk, and assess response to therapies. This review is designed to summarize the various hemodynamic measures that can characterize the aorta, the various non-invasive techniques, and applications for various disease states. PMID:26381770

  8. Optical characterization of contrast agents for optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Lee, Tin-Man; Toublan, Farah J.; Oldenburg, Amy; Sitafalwalla, Shoeb; Luo, Wei; Marks, Daniel L.; Suslick, Kenneth S.; Boppart, Stephen A.

    2003-07-01

    The use of contrast agents in almost every imaging modality has been known to enhance the sensitivity of detection and improve diagnostic capabilities by site-specifically labeling tissues or cells of interest. The imaging capabilities of Optical Coherence Tomography (OCT) need to be improved in order to detect early neoplastic changes in medicine and tumor biology. We introduce and characterize the optical properties of several types of optical contrast agents in OCT, namely encapsulating microspheres that incorporate materials including melanin, gold, and carbon. Micron-sized microspheres have been fabricated by state-of-the-art sonicating and ultrasound technology. The optical properties of optical contrast agents have been characterized according to their scattering and absorption coefficients and lifetimes using OCT and the oblique incidence reflectometry method. Finally, we demonstrate the use of these optical contrast agents in in vitro mice liver and analyze the contrast improvement from the OCT images. These optical contrast agents have the potential to improve the detection of in vivo pathologies in the future.

  9. Non-invasive photo acoustic approach for human bone diagnosis.

    PubMed

    Thella, Ashok Kumar; Rizkalla, James; Helmy, Ahdy; Suryadevara, Vinay Kumar; Salama, Paul; Rizkalla, Maher

    2016-12-01

    The existing modalities of bone diagnosis including X-ray and ultrasound may cite drawback in some cases related to health issues and penetration depth, while the ultrasound modality may lack image quality. Photo acoustic approach however, provides light energy to the acoustic wave, enabling it to activate and respond according to the propagating media (which is type of bones in this case). At the same time, a differential temperature change may result in the bio heat response, resulting from the heat absorbed across the multiple materials under study. In this work, we have demonstrated the features of using photo acoustic modality in order to non-invasively diagnose the type of human bones based on their electrical, thermal, and acoustic properties that differentiate the output response of each type. COMSOL software was utilized to combine both acoustic equations and bio heat equations, in order to study both the thermal and acoustic responses through which the differential diagnosis can be obtained. In this study, we solved both the acoustic equation and bio heat equations for four types of bones, bone (cancellous), bone (cortical), bone marrow (red), and bone marrow (yellow). 1 MHz acoustic source frequency was chosen and 10(5) W/m(2) power source was used in the simulation. The simulation tested the dynamic response of the wave over a distance of 5 cm from each side for the source. Near 2.4 cm was detected from simulation from each side of the source with a temperature change of within 0.5 K for various types of bones, citing a promising technique for a practical model to detect the type of bones via the differential temperature as well as the acoustic was response via the multiple materials associated with the human bones (skin and blood). The simulation results suggest that the PA technique may be applied to non-invasive diagnosis for the different types of bones, including cancerous bones. A practical model for detecting both the temperature change via

  10. Spectroscopic determination of Critical Micelle Concentration in aqueous and non-aqueous media using a non-invasive method.

    PubMed

    Anand, Uttam; Jash, Chandrima; Mukherjee, Saptarshi

    2011-12-15

    In this present study, we report on new methodology for determining the Critical Micelle Concentration (CMC) of a neutral surfactant Triton X-100 (TX-100) both in aqueous and non-aqueous media based on a non-invasive approach. The presence of the phenyl moiety of TX-100 was made use of as an intrinsic fluorophore and steady-state and time-resolved spectroscopy has been used to characterize the micellar systems. There are reports that external fluorophores may bring about some structural changes in the systems and the perturbations caused by these fluorophores in micellar systems may affect the shape and size of the micelles. We have also used three probes namely ANS, Rh6G and C-480 to determine the CMC of TX-100 both in aqueous and non-aqueous media and the values obtained agree very well with those estimated by the non-invasive techniques. Interestingly, for our system, we have conclusively proved that the external probes have almost no effect on the process of micellization. Although, both the invasive and non-invasive technologies report almost the same values of CMC, yet the latter methodology is free from any external perturbations and this makes the micellar/reverse micellar system, which may interact with other biological systems less prone to any physical distortions. PMID:21924731

  11. Non invasive analysis of miniature paintings: Proposal for an analytical protocol

    NASA Astrophysics Data System (ADS)

    Aceto, Maurizio; Agostino, Angelo; Fenoglio, Gaia; Gulmini, Monica; Bianco, Valentina; Pellizzi, Eleonora

    2012-06-01

    The characterisation of palettes used in manuscript illumination is a hard analytical task, due to value and fragility of the analysed items. Analysis on miniatures must be necessarily non-invasive and fast and requires the use of several techniques since no single technique is able to provide all information needed. In this work a four-step analytical protocol is proposed for non-invasive in situ characterisation of miniature paintings. The protocol allows the identification of coloured materials through the use in sequence of complementary techniques, so as to fully exploit the information given by each instrument. Preliminarily to the instrumental investigations on ancient books and miniatures is the compilation of spectroscopic databases obtained from "standard" samples prepared on parchment, according to recipes described in medieval artistic treatises. The protocol starts with an extensive investigation with UV-visible spectrophotometry in reflectance mode, collecting spectra from all the most significant painted areas in the manuscript; chemometric classification is then performed on the spectra to highlight areas possibly containing the same materials. The second step involves in-depth inspection of miniatures under optical microscopy that guides the interpretation of reflectance spectra. XRF spectrometry is then performed to characterise pigments and metal layers, to verify the presence of overlapping layers, to identify mordants in lakes and to recognise minor components that may yield information concerning provenance; in addition, chemometric classification can be performed on element concentrations to highlight similar areas. Finally, Raman spectroscopy is used to shed light on the uncertain cases, if still present. Such a procedure offers a wealth of information without causing stress to the manuscripts under analysis.

  12. Non invasive analysis of miniature paintings: proposal for an analytical protocol.

    PubMed

    Aceto, Maurizio; Agostino, Angelo; Fenoglio, Gaia; Gulmini, Monica; Bianco, Valentina; Pellizzi, Eleonora

    2012-06-01

    The characterisation of palettes used in manuscript illumination is a hard analytical task, due to value and fragility of the analysed items. Analysis on miniatures must be necessarily non-invasive and fast and requires the use of several techniques since no single technique is able to provide all information needed. In this work a four-step analytical protocol is proposed for non-invasive in situ characterisation of miniature paintings. The protocol allows the identification of coloured materials through the use in sequence of complementary techniques, so as to fully exploit the information given by each instrument. Preliminarily to the instrumental investigations on ancient books and miniatures is the compilation of spectroscopic databases obtained from "standard" samples prepared on parchment, according to recipes described in medieval artistic treatises. The protocol starts with an extensive investigation with UV-visible spectrophotometry in reflectance mode, collecting spectra from all the most significant painted areas in the manuscript; chemometric classification is then performed on the spectra to highlight areas possibly containing the same materials. The second step involves in-depth inspection of miniatures under optical microscopy that guides the interpretation of reflectance spectra. XRF spectrometry is then performed to characterise pigments and metal layers, to verify the presence of overlapping layers, to identify mordants in lakes and to recognise minor components that may yield information concerning provenance; in addition, chemometric classification can be performed on element concentrations to highlight similar areas. Finally, Raman spectroscopy is used to shed light on the uncertain cases, if still present. Such a procedure offers a wealth of information without causing stress to the manuscripts under analysis. PMID:22391225

  13. NON-INVASIVE RADIOFREQUENCY ABLATION OF CANCER TARGETED BY GOLD NANOPARTICLES

    PubMed Central

    Cardinal, Jon; Klune, John Robert; Chory, Eamon; Jeyabalan, Geetha; Kanzius, John S.; Nalesnik, Michael; Geller, David A.

    2008-01-01

    Introduction Current radiofrequency ablation (RFA) techniques require invasive needle placement and are limited by accuracy of targeting. The purpose of this study was to test a novel non-invasive radiowave machine that uses RF energy to thermally destroy tissue. Gold nanoparticles were designed and produced to facilitate tissue heating by the radiowaves. Methods A solid state radiowave machine consisting of a power generator and transmitting/receiving couplers which transmit radiowaves at 13.56 MHz was used. Gold nanoparticles were produced by citrate reduction and exposed to the RF field either in solutions testing or after incubation with HepG2 cells. A rat hepatoma model using JM-1 cells and Fisher rats was employed using direct injection of nanoparticles into the tumor to focus the radiowaves for select heating. Temperatures were measured using a fiber-optic thermometer for real-time data. Results Solutions containing gold nanoparticles heated in a time- and power-dependent manner. HepG2 liver cancer cells cultured in the presence of gold nanoparticles achieved adequate heating to cause cell death upon exposure to the RF field with no cytotoxicity attributable to the gold nanoparticles themselves. In vivo rat exposures at 35W using gold nanoparticles for tissue injection resulted in significant temperature increases and thermal injury at subcutaneous injection sites as compared to vehicle (water) injected controls. Discussion These data show that non-invasive radiowave thermal ablation of cancer cells is feasible when facilitated by gold nanoparticles. Future studies will focus on tumor selective targeting of nanoparticles for in vivo tumor destruction. PMID:18656617

  14. Non-Invasive Quantification of Cartilage Using a Novel In Vivo Bioluminescent Reporter Mouse

    PubMed Central

    Mailhiot, Sarah E.; Zignego, Donald L.; Prigge, Justin R.; Wardwell, Ella R.; Schmidt, Edward E.; June, Ronald K.

    2015-01-01

    Mouse models are common tools for examining post-traumatic osteoarthritis (OA), which involves cartilage deterioration following injury or stress. One challenge to current mouse models is longitudinal monitoring of the cartilage deterioration in vivo in the same mouse during an experiment. The objective of this study was to assess the feasibility for using a novel transgenic mouse for non-invasive quantification of cartilage. Chondrocytes are defined by expression of the matrix protein aggrecan, and we developed a novel mouse containing a reporter luciferase cassette under the inducible control of the endogenous aggrecan promoter. We generated these mice by crossing a Cre-dependent luciferase reporter allele with an aggrecan creERT2 knockin allele. The advantage of this design is that the targeted knockin retains the intact endogenous aggrecan locus and expresses the tamoxifen-inducible CreERT2 protein from a second IRES-driven open reading frame. These mice display bioluminescence in the joints, tail, and trachea, consistent with patterns of aggrecan expression. To evaluate this mouse as a technology for non-invasive quantification of cartilage loss, we characterized the relationship between loss of bioluminescence and loss of cartilage after induction with (i) ex vivo collagenase digestion, (ii) an in vivo OA model utilizing treadmill running, and (iii) age. Ex vivo experiments revealed that collagenase digestion of the femur reduced both luciferase signal intensity and pixel area, demonstrating a link between cartilage degradation and bioluminescence. In an in vivo model of experimental OA, we found decreased bioluminescent signal and pixel area, which correlated with pathological disease. We detected a decrease in both bioluminescent signal intensity and area with natural aging from 2 to 13 months of age. These results indicate that the bioluminescent signal from this mouse may be used as a non-invasive quantitative measure of cartilage. Future studies may use

  15. Optical tweezers: Characterization and systems approach to high bandwidth force estimation

    NASA Astrophysics Data System (ADS)

    Sehgal, Hullas

    In recent times, the hard boundaries between classical fields of sciences have almost disappeared. There is a cross-pollination of ideas between sciences, engineering and mathematics. This work investigates a modern tool of micro-manipulation of microscopic particles that is used primarily by bio-physicists and bio-chemists for single cell, single molecule studies. This tool called the Optical Tweezers can trap microscopic dielectric particles using radiation pressure of light. Optical tweezers is increasingly being used in bio-assays as it provides a means to observe bio-molecules non invasively and offers a spatial resolution in nanometers and force resolution in femto-Newtons at millisecond timescales. In this work, physics governing the operating principle behind optical tweezers is presented, followed by a step by step procedure to build an optical tweezers system having measurement and actuation capability along with a controller logic for feedback implementation. The working of optical tweezers system is presented using a spring mass damper model and the traditional methods of optical tweezers characterization are discussed. A comprehensive view of Optical tweezers is then presented from a system theoretic perspective, underlying the limitations of traditional methods of tweezers characterization that are based on the first principle. The role of feedback in Optical tweezers is presented along with the fundamental limitations that the plant model imposes on optical tweezers performance to be used as a force sensor for fast dynamics input force. The purpose of optical tweezers as a pico-newton force probe is emphasized and a classical controls based method to improve the bandwidth of force estimation using an ad-hoc approach of system inversion is presented. The efficacy of system inversion based method in improving the force probe capability of feedback enhanced optical tweezers is validated by experimental results. It is shown experimentally that the system

  16. Alteration of Political Belief by Non-invasive Brain Stimulation

    PubMed Central

    Chawke, Caroline; Kanai, Ryota

    2016-01-01

    People generally have imperfect introspective access to the mechanisms underlying their political beliefs, yet can confidently communicate the reasoning that goes into their decision making process. An innate desire for certainty and security in ones beliefs may play an important and somewhat automatic role in motivating the maintenance or rejection of partisan support. The aim of the current study was to clarify the role of the DLPFC in the alteration of political beliefs. Recent neuroimaging studies have focused on the association between the DLPFC (a region involved in the regulation of cognitive conflict and error feedback processing) and reduced affiliation with opposing political candidates. As such, this study used a method of non-invasive brain simulation (tRNS) to enhance activity of the bilateral DLPFC during the incorporation of political campaign information. These findings indicate a crucial role for this region in political belief formation. However, enhanced activation of DLPFC does not necessarily result in the specific rejection of political beliefs. In contrast to the hypothesis the results appear to indicate a significant increase in conservative values regardless of participant's initial political orientation and the political campaign advertisement they were exposed to. PMID:26834603

  17. Non-invasive Renal Denervation: Update on External Ultrasound Approaches.

    PubMed

    Schmieder, Roland E; Ott, Christian; Bramlage, Peter

    2016-06-01

    In the last decade, intravenous renal denervation (RDN) has emerged as an alternative to pharmacological treatment in patients with resistant hypertension, but currently involves an invasive and technically challenging procedure. The Surround Sound™ system utilises externally delivered ultrasound to achieve RDN using a completely non-invasive, automated real-time tracking system coupled with a therapeutic delivery module thereby addressing these limitations. A brief history, technical overview and summary of preclinical and clinical studies of the KonaMedical Surround Sound™ system are presented. A literature search using the terms "renal denervation", "resistant hypertension" and "external ultrasound" was performed using PubMed, and references retrieved were selected based on relevancy and year of publication (date range 1991-2015). The Surround Sound™ system appears to be a promising approach to RDN which eliminates several of the factors currently limiting the intravenous approach. So far, it has demonstrated efficacy for reducing blood pressure in resistant hypertension patients with minimal adverse effects. Several double-blind, sham-controlled clinical trials are currently underway to confirm the validity of these findings. PMID:27137523

  18. Non-Invasive Gait Monitoring in a Ubiquitous Computing House

    NASA Astrophysics Data System (ADS)

    Ohta, Yuji; Motooka, Nobuhisa; Siio, Itiro; Tsukada, Koji; Kambara, Keisuke

    Computers become smaller and cheaper from day to day, and the utilization, as daily life equipments, is now becoming ubiquitous. Therefore, it's essential to discuss the development of applications, as well as the installation of ubiquitous computing technologies into our daily living environments. Based on this idea, in order to investigate how ubiquitous computing can be used in the most efficient way, an experimental house, Ocha House, has been constructed in the campus of Ochanomizu university in 2009. In this study, we described the feature of the design of the experimental house and proposed a non-invasive gait monitoring technique as a healthcare application. Specifically, five wireless accelerometers were fixed on the floor of the house, and the floor vibration was measured when the subject walked along the accelerometers. As a result, the floor acceleration intensity was found to surge at the ground contact, and the gait cycle could be detected. By combining the simple acceleration sensors and the housing structures, human motion monitoring would become less invasive.

  19. Public viewpoints on new non-invasive prenatal genetic tests.

    PubMed

    Farrimond, Hannah R; Kelly, Susan E

    2013-08-01

    Prenatal screening programmes have been critiqued for their routine implementation according to clinical rationale without public debate. A new approach, non-invasive prenatal diagnosis (NIPD), promises diagnosis of fetal genetic disorders from a sample of maternal blood without the miscarriage risk of current invasive prenatal tests (e.g. amniocentesis). Little research has investigated the attitudes of wider publics to NIPD. This study used Q-methodology, which combines factor analysis with qualitative comments, to identify four distinct "viewpoints" amongst 71 UK men and women: 1. NIPD as a new tool in the ongoing societal discrimination against the disabled; 2. NIPD as a positive clinical application offering peace of mind in pregnancy; 3. NIPD as a medical option justified for severe disorders only; and 4. NIPD as a valid expansion of personal choice. Concerns included the "trivialisation of testing" and the implications of commercial/direct-to-consumer tests. Q-methodology has considerable potential to identify viewpoints and frame public debate about new technologies. PMID:23885055

  20. Non-Invasive Measurement of Intracranial Pressure Pulsation using Ultrasound

    NASA Technical Reports Server (NTRS)

    Ueno, Toshiaki; Ballard, R. E.; Yost, W. T.; Hargens, A. R.

    1997-01-01

    Exposure to microgravity causes a cephalad fluid shift which may elevate intracranial pressure (ICP). Elevation in ICP may affect cerebral hemodynamics in astronauts during space flight. ICP is, however, a difficult parameter to measure due to the invasiveness of currently available techniques. We already reported our development of a non-invasive ultrasound device for measurement of ICP. We recently modified the device so that we might reproducibly estimate ICP changes in association with cardiac cycles. In the first experiment, we measured changes in cranial distance with the ultrasound device in cadavera while changing ICP by infusing saline into the lateral ventricle. In the second experiment, we measured changes in cranial distance in five healthy volunteers while placing them in 60 deg, 30 deg head-up tilt, supine, and 10 deg head-down tilt position. In the cadaver study, fast Fourier transformation revealed that cranial pulsation is clearly associated with ICP pulsation. The ratio of cranial distance and ICP pulsation is 1.3microns/mmHg. In the tilting study, the magnitudes of cranial pulsation are linearly correlated to tilt angles (r=0.87). The ultrasound device has sufficient sensitivity to detect cranial pulsation in association with cardiac cycles. By analyzing the magnitude of cranial pulsation, estimates of ICP during space flight are possible.

  1. Invasive and non-invasive modalities of imaging carotid stenosis.

    PubMed

    Tang, T Y; U-King-Im, J M; Walsh, S R; Young, V E; Sadat, U; Li, Z Y; Patterson, A J; Varty, K; Gillard, J H

    2009-12-01

    Despite recent therapeutic advances, acute ischemic complications of atherosclerosis remain the primary cause of morbidity and mortality in Western countries, with carotid atherosclerotic disease one of the major preventable causes of stroke. As the impact of this disease challenges our healthcare systems, we are becoming aware that factors influencing this disease are more complex than previously realized. In current clinical practice, risk stratification relies primarily on evaluation of the degree of luminal stenosis and patient symptomatology. Adequate investigation and optimal imaging are important factors that affect the quality of a carotid endarterectomy (CEA) service and are fundamental to patient selection. Digital subtraction angiography is still perceived as the most accurate imaging modality for carotid stenosis and historically has been the cornerstone of most of the major CEA trials but concerns regarding potential neurological complications have generated substantial interest in non-invasive modalities, such as contrast-enhanced magnetic resonance angiography. The purpose of this review is to give an overview to the vascular specialist of the current imaging modalities in clinical practice to identify patients with carotid stenosis. Advantages and disadvantages of each technique are outlined. Finally, limitations of assessing luminal stenosis in general are discussed. This article will not cover imaging of carotid atheroma morphology, function and other emerging imaging modalities of assessing plaque risk, which look beyond simple luminal measurements. PMID:19935602

  2. Facilitate Insight by Non-Invasive Brain Stimulation

    PubMed Central

    Chi, Richard P.; Snyder, Allan W.

    2011-01-01

    Our experiences can blind us. Once we have learned to solve problems by one method, we often have difficulties in generating solutions involving a different kind of insight. Yet there is evidence that people with brain lesions are sometimes more resistant to this so-called mental set effect. This inspired us to investigate whether the mental set effect can be reduced by non-invasive brain stimulation. 60 healthy right-handed participants were asked to take an insight problem solving task while receiving transcranial direct current stimulation (tDCS) to the anterior temporal lobes (ATL). Only 20% of participants solved an insight problem with sham stimulation (control), whereas 3 times as many participants did so (p = 0.011) with cathodal stimulation (decreased excitability) of the left ATL together with anodal stimulation (increased excitability) of the right ATL. We found hemispheric differences in that a stimulation montage involving the opposite polarities did not facilitate performance. Our findings are consistent with the theory that inhibition to the left ATL can lead to a cognitive style that is less influenced by mental templates and that the right ATL may be associated with insight or novel meaning. Further studies including neurophysiological imaging are needed to elucidate the specific mechanisms leading to the enhancement. PMID:21311746

  3. Alteration of Political Belief by Non-invasive Brain Stimulation.

    PubMed

    Chawke, Caroline; Kanai, Ryota

    2015-01-01

    People generally have imperfect introspective access to the mechanisms underlying their political beliefs, yet can confidently communicate the reasoning that goes into their decision making process. An innate desire for certainty and security in ones beliefs may play an important and somewhat automatic role in motivating the maintenance or rejection of partisan support. The aim of the current study was to clarify the role of the DLPFC in the alteration of political beliefs. Recent neuroimaging studies have focused on the association between the DLPFC (a region involved in the regulation of cognitive conflict and error feedback processing) and reduced affiliation with opposing political candidates. As such, this study used a method of non-invasive brain simulation (tRNS) to enhance activity of the bilateral DLPFC during the incorporation of political campaign information. These findings indicate a crucial role for this region in political belief formation. However, enhanced activation of DLPFC does not necessarily result in the specific rejection of political beliefs. In contrast to the hypothesis the results appear to indicate a significant increase in conservative values regardless of participant's initial political orientation and the political campaign advertisement they were exposed to. PMID:26834603

  4. A non-invasive method of tendon force measurement.

    PubMed

    Pourcelot, Philippe; Defontaine, Marielle; Ravary, Bérangère; Lemâtre, Mickaël; Crevier-Denoix, Nathalie

    2005-10-01

    The ability to measure the forces exerted in vivo on tendons and, consequently, the forces produced by muscles on tendons, offers a unique opportunity to investigate questions in disciplines as varied as physiology, biomechanics, orthopaedics and neuroscience. Until now, tendon loads could be assessed directly only by means of invasive sensors implanted within or attached to these collagenous structures. This study shows that the forces acting on tendons can be measured, in a non-invasive way, from the analysis of the propagation of an acoustic wave. Using the equine superficial digital flexor tendon as a model, it is demonstrated that the velocity of an ultrasonic wave propagating along the main axis of a tendon increases with the force applied to this tendon. Furthermore, we show that this velocity measurement can be performed even in the presence of skin overlying the tendon. To validate this measurement technique in vivo, the ultrasonic velocity plots obtained in the Achilles tendon at the walk were compared to the loads plots reported by other authors using invasive transducers. PMID:16084214

  5. Reducing proactive aggression through non-invasive brain stimulation.

    PubMed

    Dambacher, Franziska; Schuhmann, Teresa; Lobbestael, Jill; Arntz, Arnoud; Brugman, Suzanne; Sack, Alexander T

    2015-10-01

    Aggressive behavior poses a threat to human collaboration and social safety. It is of utmost importance to identify the functional mechanisms underlying aggression and to develop potential interventions capable of reducing dysfunctional aggressive behavior already at a brain level. We here experimentally shifted fronto-cortical asymmetry to manipulate the underlying motivational emotional states in both male and female participants while assessing the behavioral effects on proactive and reactive aggression. Thirty-two healthy volunteers received either anodal transcranial direct current stimulation to increase neural activity within right dorsolateral prefrontal cortex, or sham stimulation. Aggressive behavior was measured with the Taylor Aggression Paradigm. We revealed a general gender effect, showing that men displayed more behavioral aggression than women. After the induction of right fronto-hemispheric dominance, proactive aggression was reduced in men. This study demonstrates that non-invasive brain stimulation can reduce aggression in men. This is a relevant and promising step to better understand how cortical brain states connect to impulsive actions and to examine the causal role of the prefrontal cortex in aggression. Ultimately, such findings could help to examine whether the brain can be a direct target for potential supportive interventions in clinical settings dealing with overly aggressive patients and/or violent offenders. PMID:25680991

  6. Non-invasive fecal metabonomic detection of colorectal cancer

    PubMed Central

    Phua, Lee Cheng; Chue, Xiu Ping; Koh, Poh Koon; Cheah, Peh Yean; Ho, Han Kiat; Chan, Eric Chun Yong

    2014-01-01

    Colorectal cancer (CRC) is a major cause of mortality in many developed countries. Effective screening strategies were called for to facilitate timely detection and to promote a better clinical outcome. In this study, the role of fecal metabonomics in the non-invasive detection of CRC was investigated. Gas chromatography/time-of-flight mass spectrometry (GC/TOFMS) was utilized for the metabolic profiling of feces obtained from 11 CRC patients and 10 healthy subjects. Concurrently, matched tumor and normal mucosae surgically excised from CRC patients were profiled. CRC patients were differentiated clearly from healthy subjects based on their fecal metabonomic profiles (orthogonal partial least squares discriminant analysis [OPLS-DA], 1 predictive and 3 Y-orthogonal components, R2X = 0.373, R2Y = 0.995, Q2 [cumulative] = 0.215). The robustness of the OPLS-DA model was demonstrated by an area of 1 under the receiver operator characteristic curve. OPLS-DA revealed fecal marker metabolites (e.g., fructose, linoleic acid, and nicotinic acid) that provided novel insights into the tumorigenesis of CRC. Interestingly, a disparate set of CRC-related metabolic aberrations occurred at the tissue level, implying the contribution of processes beyond the direct shedding of tumor cells to the fecal metabotype. In summary, this work established proof-of-principle for GC/TOFMS-based fecal metabonomic detection of CRC and offered new perspectives on the underlying mechanisms. PMID:24424155

  7. Non-invasive instant genotyping of fluorescently labelled transgenic mice.

    PubMed

    Fink, Dieter; Yau, Tien Yin; Kolbe, Thomas; Rülicke, Thomas

    2015-01-01

    Fluorescence proteins have been useful as genetic reporters for a wide range of applications in biomedical research and are frequently used for the analysis of transgene activity. Here, we show that expression levels of the ubiquitously expressed fluorescent proteins eGFP, mCherry, and tdTomato can be measured in transgenic mouse lines with random or targeted integrations. We identified the tail of the mouse as the tissue best suited for quantifying fluorescence intensity and show that expression levels in the tail correlate with gene dose. This allows for instant non-invasive determination of the genetic condition at the transgenic locus (hemizygous/heterozygous and homozygous), while simultaneously providing an objective comparison for transgene expression levels among different mouse lines. In summary, we demonstrate for the first time that the gene dose of a ubiquitously expressed fluorescence reporter can be reliably quantified and directly linked to the genotype of transgenic mice. Based on this information, animals with the appropriate genotype can be instantly selected without laborious analysis for establishing and breeding of new transgenic lines, reducing the number of "waste" animals. Furthermore, no tissue sampling is necessary, which is a significant refinement of genotyping procedures. Both aspects are important improvements for the genotyping of transgenic mice that follow the principles of the 3 Rs (reduction and refinement). PMID:25981046

  8. Non-invasive prenatal screening for trisomy 21: Consumers' perspectives.

    PubMed

    Higuchi, Emily C; Sheldon, Jane P; Zikmund-Fisher, Brian J; Yashar, Beverly M

    2016-02-01

    Non-invasive prenatal screening (NIPS) has the potential to dramatically increase the prenatal detection rate of Down syndrome because of improvements in safety and accuracy over existing tests. There is concern that NIPS could lead to more negative attitudes towards Down syndrome and less support for individuals with Down syndrome. To assess the impact of NIPS on support for prenatal testing, decision-making about testing, and beliefs or attitudes about Down syndrome, we performed an Internet-based experiment using adults (N = 1,789) recruited through Amazon Mechanical Turk. Participants were randomly assigned to read a mock news article about NIPS, a mock news article about amniocentesis, or no article. The content in the two articles varied only in their descriptions of the test characteristics. Participants then answered questions about their support for testing, hypothetical testing decision, and beliefs and attitudes about Down syndrome. Reading the mock NIPS news article predicted increased hypothetical test uptake. In addition, the NIPS article group also agreed more strongly that pregnant women, in general, should utilize prenatal testing. We also found that the more strongly participants supported prenatal testing for pregnant women, the less favorable their attitudes towards individuals with Down syndrome; providing some evidence that NIPS may indirectly result in more negative perceptions of individuals with this diagnosis. PMID:26553705

  9. Use of dexmedetomidine to facilitate non-invasive ventilation

    PubMed Central

    DeMuro, Jonas P; Mongelli, Michael N; Hanna, Adel F

    2013-01-01

    Patients with chronic obstructive pulmonary disease and congestive heart failure exacerbations, as well as pneumonia benefit from the use of non-invasive ventilation (NIV), due to increased patient comfort and a reduced incidence of ventilator-associated pneumonia. However, some patients do not tolerate NIV due to anxiety or agitation, and traditionally physicians have withheld sedation from these patients due to concerns of loss of airway protection and respiratory depression. We report our recent experience with a 91-year-old female who received NIV for acute respiratory distress secondary to pneumonia. The duration of NIV was a total time period of 86 h, using the bilevel positive airway pressure mode via a full face mask. The patient was initially agitated with the NIV, but with the addition of the dexmedetomidine, she tolerated it well. The dexmedetomidine was administered without a loading dose, as a continuous infusion ranging from 0.2 to 0.5 mcg/kg/hr, titrated to a Ramsey score of three. This case illustrates the safe use of dexmedetomidine to facilitate NIV, and improve compliance, which may reduce ICU length of stay. PMID:24459626

  10. Novel non-invasive protein and peptide drug delivery approaches.

    PubMed

    Wallis, L; Kleynhans, E; Toit, T Du; Gouws, C; Steyn, D; Steenekamp, J; Viljoen, J; Hamman, J

    2014-01-01

    Protein and peptide based therapeutics are typically administered by injection due to their poor uptake when administered via enteral routes of drug administration. Unfortunately, chronic administration of these drugs through multiple injections presents certain patient related problems and it is difficult to mimic the normal physiological release patterns via this mode of drug administration. A need therefore exists to non-invasively deliver these drugs by means of alternative ways such as via the oral, pulmonary, nasal, transdermal and buccal administration routes. Although some attempts of needle free peptide and protein drug delivery have progressed to the clinical stage, relatively limited success has been achieved in terms of commercially available products. Despite the low frequency of clinical breakthroughs with noninvasive protein drug delivery this far, it remains an active research area with renewed interest not only due to its improved therapeutic potential, but also due to the attractive commercial outcomes it offers. It is the aim of this review article to reflect on the main strategies investigated to overcome the barriers against effective systemic protein drug delivery in different routes of drug administration. Approaches based on chemical modifications and pharmaceutical technologies are discussed with reference to examples of drugs and devices that have shown potential, while attempts that have failed are also briefly outlined. PMID:25106909

  11. Optical textures: characterizing spatiotemporal chaos.

    PubMed

    Clerc, Marcel G; González-Cortés, Gregorio; Odent, Vincent; Wilson, Mario

    2016-07-11

    Macroscopic systems subjected to injection and dissipation of energy can exhibit complex spatiotemporal behaviors as result of dissipative self-organization. Here, we report a one- and two-dimensional pattern forming setup, which exhibits a transition from stationary patterns to spatiotemporal chaotic textures, based on a nematic liquid crystal layer with spatially modulated input beam and optical feedback. Using an adequate projection of spatiotemporal diagrams, we determine the largest Lyapunov exponent. Jointly, this exponent and Fourier transform allow us to distinguish between spatiotemporal chaos and amplitude turbulence concepts, which are usually merged. PMID:27410822

  12. Non-invasive mechanical ventilation and epidural anesthesia for an emergency open cholecystectomy.

    PubMed

    Yurtlu, Bülent Serhan; Köksal, Bengü; Hancı, Volkan; Turan, Işıl Özkoçak

    2016-01-01

    Non-invasive ventilation is an accepted treatment modality in both acute exacerbations of respiratory diseases and chronic obstructive lung disease. It is commonly utilized in the intensive care units, or for postoperative respiratory support in post-anesthesia care units. This report describes intraoperative support in non-invasive ventilation to neuroaxial anesthesia for an emergency upper abdominal surgery. PMID:27591472

  13. Towards novel compact laser sources for non-invasive diagnostics and treatment

    NASA Astrophysics Data System (ADS)

    Rafailov, Edik U.; Litvinova, Karina S.; Sokolovski, Sergei G.

    2015-08-01

    An important field of application of lasers is biomedical optics. Here, they offer great utility for diagnosis, therapy and surgery. For the development of novel methods of laser-based biomedical diagnostics careful study of light propagation in biological tissues is necessary to enhance our understanding of the optical measurements undertaken, increase research and development capacity and the diagnostic reliability of optical technologies. Ultimately, fulfilling these requirements will increase uptake in clinical applications of laser based diagnostics and therapeutics. To address these challenges informative biomarkers relevant to the biological and physiological function or disease state of the organism must be selected. These indicators are the results of the analysis of tissues and cells, such as blood. For non-invasive diagnostics peripheral blood, cells and tissue can potentially provide comprehensive information on the condition of the human organism. A detailed study of the light scattering and absorption characteristics can quickly detect physiological and morphological changes in the cells due to thermal, chemical, antibiotic treatments, etc [1-5]. The selection of a laser source to study the structure of biological particles also benefits from the fact that gross pathological changes are not induced and diagnostics make effective use of the monochromatic directional coherence properties of laser radiation.

  14. Ovarian tissue characterization using bulk optical properties

    NASA Astrophysics Data System (ADS)

    Tavakoli, B.; Xu, Y.; Zhu, Q.

    2013-03-01

    Ovarian cancer, the deadliest of all gynecologic cancers, is not often found in its early stages due to few symptoms and no reliable screening test. Optical imaging has a great potential to improve the ovarian cancer detection and diagnosis. In this study we have characterized the bulk optical properties of 26 ex-vivo human ovaries using a Diffuse Optical Tomography system. The quantitative values indicated that, in the postmenopausal group, malignant ovaries showed significantly lower scattering coefficient than normal ones. The scattering parameter is largely related to the collagen content that has shown a strong correlation with the cancer development.

  15. Characterization of magneto-optical media

    NASA Technical Reports Server (NTRS)

    Hajjar, Roger A.; Wu, Te-Ho; Mansuripur, M.

    1991-01-01

    Amorphous rare earth-transition metal (RE-TM) alloys and compositionally modulated TM/TM films were characterized in terms of their magnetic, magneto-optic, and galvanomagnetic properties. The loop tracer, vibrating sample magnetometer (VSM), and Rutherford Backscattering (RBS) facility were used to characterize and analyze the various properties of these magneto-optical storage media. Kerr effect, ellipticity, coercivity, and anisotropy at various temperatures, magnetoresistance, and resistivity are among the properties measured in Co/Pt films, Co/Pd films, and TbFeCo films.

  16. Non-invasive quantification of lower limb mechanical alignment in flexion

    PubMed Central

    Deakin, Angela; Fogg, Quentin A.; Picard, Frederic

    2014-01-01

    Objective Non-invasive navigation techniques have recently been developed to determine mechanical femorotibial alignment (MFTA) in extension. The primary aim of this study was to evaluate the precision and accuracy of an image-free navigation system with new software designed to provide multiple kinematic measurements of the knee. The secondary aim was to test two types of strap material used to attach optical trackers to the lower limb. Methods Seventy-two registrations were carried out on 6 intact embalmed cadaveric specimens (mean age: 77.8 ± 12 years). A validated fabric strap, bone screws and novel rubber strap were used to secure the passive tracker baseplate for four full experiments with each knee. The MFTA angle was measured under the conditions of no applied stress, valgus stress, and varus stress. These measurements were carried out at full extension and at 30°, 40°, 50° and 60° of flexion. Intraclass correlation coefficients, repeatability coefficients, and limits of agreement (LOA) were used to convey precision and agreement in measuring MFTA with respect to each of the independent variables, i.e., degree of flexion, applied coronal stress, and method of tracker fixation. Based on the current literature, a repeatability coefficient and LOA of ≤3° were deemed acceptable. Results The mean fixed flexion for the 6 specimens was 12.8° (range: 6–20°). The mean repeatability coefficient measuring MFTA in extension with screws or fabric strapping of the baseplate was ≤2°, compared to 2.3° using rubber strapping. When flexing the knee, MFTA measurements taken using screws or fabric straps remained precise (repeatability coefficient ≤3°) throughout the tested range of flexion (12.8–60°); however, using rubber straps, the repeatability coefficient was >3° beyond 50° flexion. In general, applying a varus/valgus stress while measuring MFTA decreased precision beyond 40° flexion. Using fabric strapping, excellent repeatability

  17. Apparatus and method for characterizing ultrafast polarization varying optical pulses

    DOEpatents

    Smirl, Arthur; Trebino, Rick P.

    1999-08-10

    Practical techniques are described for characterizing ultrafast potentially ultraweak, ultrashort optical pulses. The techniques are particularly suited to the measurement of signals from nonlinear optical materials characterization experiments, whose signals are generally too weak for full characterization using conventional techniques.

  18. Microwave radiometry for non-invasive detection of vesicoureteral reflux (VUR) following bladder warming

    NASA Astrophysics Data System (ADS)

    Stauffer, Paul R.; Maccarini, Paolo F.; Arunachalam, Kavitha; De Luca, Valeria; Salahi, Sara; Boico, Alina; Klemetsen, Oystein; Birkelund, Yngve; Jacobsen, Svein K.; Bardati, Fernando; Tognolotti, Piero; Snow, Brent

    2011-03-01

    Background: Vesicoureteral reflux (VUR) is a serious health problem leading to renal scarring in children. Current VUR detection involves traumatic x-ray imaging of kidneys following injection of contrast agent into bladder via invasive Foley catheter. We present an alternative non-invasive approach for detecting VUR by radiometric monitoring of kidney temperature while gently warming the bladder. Methods: We report the design and testing of: i) 915MHz square slot antenna array for heating bladder, ii) EMI-shielded log spiral microstrip receive antenna, iii) high-sensitivity 1.375GHz total power radiometer, iv) power modulation approach to increase urine temperature relative to overlying perfused tissues, and v) invivo porcine experiments characterizing bladder heating and radiometric temperature of aaline filled 30mL balloon "kidney" implanted 3-4cm deep in thorax and varied 2-6°C from core temperature. Results: SAR distributions are presented for two novel antennas designed to heat bladder and monitor deep kidney temperatures radiometrically. We demonstrate the ability to heat 180mL saline in in vivo porcine bladder to 40-44°C while maintaining overlying tissues <38°C using time-modulated square slot antennas coupled to the abdomen with room temperature water pad. Pathologic evaluations confirmed lack of acute thermal damage in pelvic tissues for up to three 20min bladder heat exposures. The radiometer clearly recorded 2-6°C changes of 30mL "kidney" targets at depth in 34°C invivo pig thorax. Conclusion: A 915MHz antenna array can gently warm in vivo pig bladder without toxicity while a 1.375GHz radiometer with log spiral receive antenna detects >=2°C rise in 30mL "urine" located 3-4cm deep in thorax, demonstrating more than sufficient sensitivity to detect Grade 4-5 reflux of warmed urine for non-invasive detection of VUR.

  19. Non-invasive in vivo imaging of early metabolic tumor response to therapies targeting choline metabolism.

    PubMed

    Mignion, Lionel; Danhier, Pierre; Magat, Julie; Porporato, Paolo E; Masquelier, Julien; Gregoire, Vincent; Muccioli, Giulio G; Sonveaux, Pierre; Gallez, Bernard; Jordan, Bénédicte F

    2016-04-15

    The cholinic phenotype, characterized by elevated phosphocholine and a high production of total-choline (tCho)-containing metabolites, is a metabolic hallmark of cancer. It can be exploited for targeted therapy. Non-invasive imaging biomarkers are required to evaluate an individual's response to targeted anticancer agents that usually do not rapidly cause tumor shrinkage. Because metabolic changes can manifest at earlier stages of therapy than changes in tumor size, the aim of the current study was to evaluate (1)H-MRS and diffusion-weighted MRI (DW-MRI) as markers of tumor response to the modulation of the choline pathway in mammary tumor xenografts. Inhibition of choline kinase activity was achieved with the direct pharmacological inhibitor H-89, indirect inhibitor sorafenib and down-regulation of choline-kinase α (ChKA) expression using specific short-hairpin RNA (shRNA). While all three strategies significantly decreased tCho tumor content in vivo, only sorafenib and anti-ChKA shRNA significantly repressed tumor growth. The increase of apparent-diffusion-coefficient of water (ADCw) measured by DW-MRI, was predictive of the induced necrosis and inhibition of the tumor growth in sorafenib treated mice, while the absence of change in ADC values in H89 treated mice predicted the absence of effect in terms of tumor necrosis and tumor growth. In conclusion, (1)H-choline spectroscopy can be useful as a pharmacodynamic biomarker for choline targeted agents, while DW-MRI can be used as an early marker of effective tumor response to choline targeted therapies. DW-MRI combined to choline spectroscopy may provide a useful non-invasive marker for the early clinical assessment of tumor response to therapies targeting choline signaling. PMID:26595604

  20. Terahertz material characterization for nonreciprocal integrated optics

    NASA Astrophysics Data System (ADS)

    Mičica, Martin; Postava, Kamil; Vanwolleghem, Mathias; Horák, Tomáś; Lampin, Jean François; Pištora, Jaromír.

    2015-05-01

    Interest in nonreciprocal terahertz (THz) integrated optics makes necessity to look for new materials active in this region and precisely characterize their optical properties. In this paper we present important aspects of the methods for determination of optical functions in far infrared (FIR) and THz spectral range. The techniques are applied to polyethylene cyclic olefin copolymer (Topas) and hexaferrites (BaFe12O19, SrFe12O19). Topas is promising material in integrated optics for THz radiation, thanks to its low absorption in this region. On the other hand, hexaferrites with its magneto-optic properties can be used for nonreciprocal integrated optic parts and radiation control. Samples were studied by THz time domain spectroscopy (THz-TDS) in spectral range 2 - 100 cm-1 by transmission and reflection. Advantage of presented THz time domain spectroscopy is measurement of the electric field wavefunction, which allows to obtain both the amplitude and phase spectra. In results we provide measured data, processing, and final computed optical properties of Topas and hexaferrites which reveal interesting optical behaviour in THz spectral range.

  1. Skin Hydration Assessment through Modern Non-Invasive Bioengineering Technologies

    PubMed Central

    CONSTANTIN, Maria-Magdalena; POENARU, Elena; POENARU, Calin; CONSTANTIN, Traian

    2014-01-01

    Non-invasive bioengineering technologies continuously discovered and developed in recent decades provide a significant input to research development and remarkably contribute to the improvement of medical education and care to our patients. Aim: Assessing skin hydration by using the capacitance method for a group of patients with allergic contact dermatitis versus healthy subjects, before and after applying a moisturiser (assessing the immediate and long-term effectiveness of hydration). Results: For both groups, but especially for the patients with dry skin, there was a clear improvement of hydration, statistically significant after applying the moisturiser. In the case of the patients with allergic contact dermatitis, hydration was at a maximum immediately after the first application, and then maintained an increased level after 7 and 28 days, respectively. In the healthy subjects, the increase in hydration was lower, but progressive. The moisturiser determined an increase in hydration for all age groups, but those who showed the most obvious effect were the young adults (18-29 years old) with an increase of 19.9%. The maintenance effect of hydration lasted for 28 days, while the improvement was important for allergic skin (17.1%) and significant for healthy skin (10.9%). Conclusion: The assessment of epidermal hydration performed by using the corneometer showed very good hydration of the stratum corneum for both groups studied, with immediate and long-term effect. This study also showed that the degree of skin hydration was inversely proportional with age. The corneometer is easy to use, efficient and widely utilised in international studies for measurements in healthy or pathological conditions, for quantitative assessment of the effectiveness of various preparations intended for application to the skin surface, under well-controlled and standardised conditions. PMID:25553123

  2. Early non-invasive ventilation treatment for severe influenza pneumonia.

    PubMed

    Masclans, J R; Pérez, M; Almirall, J; Lorente, L; Marqués, A; Socias, L; Vidaur, L; Rello, J

    2013-03-01

    The role of non-invasive ventilation (NIV) in acute respiratory failure caused by viral pneumonia remains controversial. Our objective was to evaluate the use of NIV in a cohort of (H1N1)v pneumonia. Usefulness and success of NIV were assessed in a prospective, observational registry of patients with influenza A (H1N1) virus pneumonia in 148 Spanish intensive care units (ICUs) in 2009-10. Significant variables for NIV success were included in a multivariate analysis. In all, 685 patients with confirmed influenza A (H1N1)v viral pneumonia were admitted to participating ICUs; 489 were ventilated, 177 with NIV. The NIV was successful in 72 patients (40.7%), the rest required intubation. Low Acute Physiology and Chronic Health Evaluation (APACHE) II, low Sequential Organ Failure Assessment (SOFA) and absence of renal failure were associated with NIV success. Success of NIV was independently associated with fewer than two chest X-ray quadrant opacities (OR 3.5) and no vasopressor requirement (OR 8.1). However, among patients with two or more quadrant opacities, a SOFA score ≤7 presented a higher success rate than those with SOFA score >7 (OR 10.7). Patients in whom NIV was successful required shorter ventilation time, shorter ICU stay and hospital stay than NIV failure. In patients in whom NIV failed, the delay in intubation did not increase mortality (26.5% versus 24.2%). Clinicians used NIV in 25.8% of influenza A (H1N1)v viral pneumonia admitted to ICU, and treatment was effective in 40.6% of them. NIV success was associated with shorter hospital stay and mortality similar to non-ventilated patients. NIV failure was associated with a mortality similar to those who were intubated from the start. PMID:22404211

  3. Non-invasive Thrombolysis using Microtripsy: A Parameter Study

    PubMed Central

    Zhang, Xi; Jin, Lifang; Vlaisavljevich, Eli; Owens, Gabe E.; Gurm, Hitinder S.; Cain, Charles A.; Xu, Zhen

    2016-01-01

    Histotripsy fractionates soft tissue by well-controlled acoustic cavitation using microsecond-long, high-intensity ultrasound pulses. The feasibility of using histotripsy as a non-invasive, drug-free, and image-guided thrombolysis method has been shown previously. A new histotripsy approach, termed Microtripsy, has recently been investigated for the thrombolysis application to improve treatment accuracy and avoid potential vessel damage. In this study, we investigated the effects of pulse repetition frequency (PRF) on microtripsy thrombolysis. Microtripsy thrombolysis treatments using different PRFs (5, 50, and 100 Hz) and doses (20, 50, and 100 pulses) were performed on blood clots in an in vitro vessel flow model. To quantitatively evaluate the microtripsy thrombolysis effect, the location of focal cavitation, the incident rate of pre-focal cavitation on the vessel wall, the size and location of the resulting flow channel, and the generated clot debris particles were measured. The results demonstrated that focal cavitation was always well-confined in the vessel lumen without contacting the vessel wall for all PRFs. Pre-focal cavitation on the front vessel wall was never observed at 5Hz PRF, but occasionally observed at PRFs of 50 Hz (1.2%) and 100 Hz (5.4%). However, the observed pre-focal cavitation was weak and didn’t significantly impact the focal cavitation. Results further demonstrated that, although the extent of clot fractionation per pulse was the highest at 5 Hz PRF at the beginning of treatment (<20 pulses), 100 Hz PRF generated the largest flow channels with a much shorter treatment time. Finally, results showed fewer large debris particles were generated at a higher PRF. Overall, the results of this study suggest that a higher PRF (50 or 100 Hz) may be a better choice for microtripsy thrombolysis to use clinically due to the larger resulting flow channel, shorter treatment time, and smaller debris particles. PMID:26670850

  4. Non-invasive prenatal testing: ethical issues explored

    PubMed Central

    de Jong, Antina; Dondorp, Wybo J; de Die-Smulders, Christine E M; Frints, Suzanne G M; de Wert, Guido M W R

    2010-01-01

    This paper explores the ethical implications of introducing non-invasive prenatal diagnostic tests (NIPD tests) in prenatal screening for foetal abnormalities. NIPD tests are easy and safe and can be performed early in pregnancy. Precisely because of these features, it is feared that informed consent may become more difficult, that both testing and selective abortion will become ‘normalized', and that there will be a trend towards accepting testing for minor abnormalities and non-medical traits as well. In our view, however, the real moral challenge of NIPD testing consists in the possibility of linking up a technique with these features (easy, safe and early) with new genomic technologies that allow prenatal diagnostic testing for a much broader range of abnormalities than is the case in current procedures. An increase in uptake and more selective abortions need not in itself be taken to signal a thoughtless acceptance of these procedures. However, combining this with considerably enlarging the scope of NIPD testing will indeed make informed consent more difficult and challenge the notion of prenatal screening as serving reproductive autonomy. If broad NIPD testing includes later-onset diseases, the ‘right not to know' of the future child will become a new issue in the debate about prenatal screening. With regard to the controversial issue of selective abortion, it may make a morally relevant difference that after NIPD testing, abortion can be done early. A lower moral status may be attributed to the foetus at that moment, given the dominant opinion that the moral status of the foetus progressively increases with its development. PMID:19953123

  5. Non-invasive investigation of inflammatory bowel disease

    PubMed Central

    Tibble, JA; Bjarnason, I

    2001-01-01

    The assessment of inflammatory activity in intestinal disease in man can be done using a variety of different techniques. These range from the use of non-invasive acute phase inflammatory markers measured in plasma such as C reactive protein (CRP) and the erythrocyte sedimentation rate (ESR) (both of which give an indirect assessment of disease activity) to the direct assessment of disease activity by intestinal biopsy performed during endoscopy in association with endoscopic scoring systems. Both radiology and endoscopy are conventional for the diagnosis of inflammatory bowel disease (IBD). However these techniques have severe limitations when it comes to assessing functional components of the disease such as activity and prognosis. Here we briefly review the value of two emerging intestinal function tests. Intestinal permeability, although ideally suited for diagnostic screening for small bowel Crohn’s disease, appears to give reliable predictive data for imminent relapse of small bowel Crohn’s disease and it can be used to assess responses to treatment. More significantly it is now clear that single stool assay of neutrophil specific proteins (calprotectin, lactoferrin) give the same quantitative data on intestinal inflammation as the 4-day faecal excretion of 111Indium labelled white cells. Faecal calprotectin is shown to be increased in over 95% of patients with IBD and correlates with clinical disease activity. It reliably differentiates between patients with IBD and irritable bowel syndrome. More importantly, at a given faecal calprotectin concentration in patients with quiescent IBD, the test has a specificity and sensitivity in excess of 85% in predicting clinical relapse of disease. This suggests that relapse of IBD is closely related to the degree of intestinal inflammation and suggests that targeted treatment at an asymptomatic stage of the disease may be indicated. PMID:11819811

  6. Optical characterization of ultrabright LEDs

    SciTech Connect

    Benavides, Juan Manuel; Webb, Robert H

    2005-07-01

    Ultrabright light emitting diodes (LEDs) are a new light source for visual psychophysics and microscopy. The new LEDs are intended primarily for room and exterior illumination, and the manufacturers' specifications are adequate for that. However, we use them as light sources in situations where a more complete characterization may be useful. For one set of LEDs we have measured the radiometric intensity and its distribution in space and wavelength, and we have tested for interactions of these variables and their dependence on driver configuration. We describe techniques for making these measurements and give a link to a simple calculator for converting among radiometric and photometric measures, as well as an evaluation of the safety considerations these very bright sources demand.

  7. Characterization of passive polymer optical waveguides

    NASA Astrophysics Data System (ADS)

    Joehnck, Matthias; Kalveram, Stefan; Lehmacher, Stefan; Pompe, Guido; Rudolph, Stefan; Neyer, Andreas; Hofstraat, Johannes W.

    1999-05-01

    The characterization of monomode passive polymer optical devices fabricated according to the POPCORN technology by methods originated from electron, ion and optical spectroscopy is summarized. Impacts of observed waveguide perturbations on the optical characteristics of the waveguide are evaluated. In the POPCORN approach optical components for telecommunication applications are fabricated by photo-curing of liquid halogenated (meth)acrylates which have been applied on moulded thermoplastic substrates. For tuning of waveguide material refractive indices with respect to the substrate refractive index frequently comonomer mixtures are used. The polymerization characteristics, especially the polymerization kinetics of individual monomers, determine the formation of copolymers. Therefore the unsaturation as function of UV-illumination time in the formation of halogenated homo- and copolymers has been examined. From different suitable copolymer system, after characterization of their glass transition temperatures, their curing behavior and their refractive indices as function of the monomer ratios, monomode waveguides applying PMMA substrates have been fabricated. To examine the materials composition also in the 6 X 6 micrometers 2 waveguides they have been visualized by transmission electron microscopy. With this method e.g. segregation phenomena could be observed in the waveguide cross section characterization as well. The optical losses in monomode waveguides caused by segregation and other materials induce defects like micro bubbles formed as a result of shrinkage have been quantized by return loss measurements. Defects causing scattering could be observed by convocal laser scanning microscopy and by conventional light microscopy.

  8. Non-invasive detection of iron deficiency by fluorescence measurement of erythrocyte zinc protoporphyrin in the lip.

    PubMed

    Hennig, Georg; Homann, Christian; Teksan, Ilknur; Hasbargen, Uwe; Hasmüller, Stephan; Holdt, Lesca M; Khaled, Nadia; Sroka, Ronald; Stauch, Thomas; Stepp, Herbert; Vogeser, Michael; Brittenham, Gary M

    2016-01-01

    Worldwide, more individuals have iron deficiency than any other health problem. Most of those affected are unaware of their lack of iron, in part because detection of iron deficiency has required a blood sample. Here we report a non-invasive method to optically measure an established indicator of iron status, red blood cell zinc protoporphyrin, in the microcirculation of the lower lip. An optical fibre probe is used to illuminate the lip and acquire fluorescence emission spectra in ∼1 min. Dual-wavelength excitation with spectral fitting is used to distinguish the faint zinc protoporphyrin fluorescence from the much greater tissue background fluorescence, providing immediate results. In 56 women, 35 of whom were iron-deficient, the sensitivity and specificity of optical non-invasive detection of iron deficiency were 97% and 90%, respectively. This fluorescence method potentially provides a rapid, easy to use means for point-of-care screening for iron deficiency in resource-limited settings lacking laboratory infrastructure. PMID:26883939

  9. Non-invasive detection of iron deficiency by fluorescence measurement of erythrocyte zinc protoporphyrin in the lip

    PubMed Central

    Hennig, Georg; Homann, Christian; Teksan, Ilknur; Hasbargen, Uwe; Hasmüller, Stephan; Holdt, Lesca M.; Khaled, Nadia; Sroka, Ronald; Stauch, Thomas; Stepp, Herbert; Vogeser, Michael; Brittenham, Gary M.

    2016-01-01

    Worldwide, more individuals have iron deficiency than any other health problem. Most of those affected are unaware of their lack of iron, in part because detection of iron deficiency has required a blood sample. Here we report a non-invasive method to optically measure an established indicator of iron status, red blood cell zinc protoporphyrin, in the microcirculation of the lower lip. An optical fibre probe is used to illuminate the lip and acquire fluorescence emission spectra in ∼1 min. Dual-wavelength excitation with spectral fitting is used to distinguish the faint zinc protoporphyrin fluorescence from the much greater tissue background fluorescence, providing immediate results. In 56 women, 35 of whom were iron-deficient, the sensitivity and specificity of optical non-invasive detection of iron deficiency were 97% and 90%, respectively. This fluorescence method potentially provides a rapid, easy to use means for point-of-care screening for iron deficiency in resource-limited settings lacking laboratory infrastructure. PMID:26883939

  10. Optical Characterization of Metallic Aerosols

    NASA Technical Reports Server (NTRS)

    Sun, Wenbo; Lin, Bing

    2005-01-01

    Airborne metallic particulates from industry and urban sources are highly conducting aerosols. The characterization of these pollutant particles is important for environment monitoring and protection. Because these metallic particulates are highly reflective, their effect on local weather or regional radiation budget may also need to be studied. In this work, light scattering characteristics of these metallic aerosols are studied using exact solutions on perfectly conducting spherical and cylindrical particles. It is found that for perfectly conducting spheres and cylinders, when scattering angle is larger than approx. 90 deg. the linear polarization degree of the scattered light is very close to zero. This light scattering characteristics of perfectly conducting particles is significantly different from that of other aerosols. When these perfectly conducting particles are immersed in an absorbing medium, this light scattering characteristics does not show significant change. Therefore, measuring the linear polarization of scattered lights at backward scattering angles can detect and distinguish metallic particulates from other aerosols. This result provides a great potential of metallic aerosol detection and monitoring for environmental protection.

  11. Electro-Optical Characterization at NREL

    SciTech Connect

    Keyes, B. M.; Dippo, P.; Gedvilas, L.; Johnston, S.; Levi, D.; Metzger, W.; Sopori, B.

    2005-11-01

    One of the core issues in all of the photovoltaics technologies is relating PV device performance to the methods and materials used to produce them. Due to the nature of PV devices, the electronic and optical properties of the materials are key to device performance. The relationship between materials growth and processing, the resulting electro-optical properties, and device performance can be extremely complex and difficult to determine without direct measurement of these properties. Accurate and timely measurement of the electro-optical properties as a function of device processing provides researchers and manufacturers with the knowledge they need to troubleshoot problems and develop the knowledge base necessary for reducing cost, maximizing efficiency, improving reliability, and enhancing manufacturability. The Electro-optical Characterization Team at NREL provides this support for all internal and external projects funded by the PV Program.

  12. Murine Model for Non-invasive Imaging to Detect and Monitor Ovarian Cancer Recurrence

    PubMed Central

    Sumi, Natalia J.; Lima, Eydis; Pizzonia, John; Orton, Sean P.; Craveiro, Vinicius; Joo, Wonduk; Holmberg, Jennie C.; Gurrea, Marta; Yang-Hartwich, Yang; Alvero, Ayesha; Mor, Gil

    2014-01-01

    Epithelial ovarian cancer is the most lethal gynecologic malignancy in the United States. Although patients initially respond to the current standard of care consisting of surgical debulking and combination chemotherapy consisting of platinum and taxane compounds, almost 90% of patients recur within a few years. In these patients the development of chemoresistant disease limits the efficacy of currently available chemotherapy agents and therefore contributes to the high mortality. To discover novel therapy options that can target recurrent disease, appropriate animal models that closely mimic the clinical profile of patients with recurrent ovarian cancer are required. The challenge in monitoring intra-peritoneal (i.p.) disease limits the use of i.p. models and thus most xenografts are established subcutaneously. We have developed a sensitive optical imaging platform that allows the detection and anatomical location of i.p. tumor mass. The platform includes the use of optical reporters that extend from the visible light range to near infrared, which in combination with 2-dimensional X-ray co-registration can provide anatomical location of molecular signals. Detection is significantly improved by the use of a rotation system that drives the animal to multiple angular positions for 360 degree imaging, allowing the identification of tumors that are not visible in single orientation. This platform provides a unique model to non-invasively monitor tumor growth and evaluate the efficacy of new therapies for the prevention or treatment of recurrent ovarian cancer. PMID:25407815

  13. Fiber-based hybrid probe for non-invasive cerebral monitoring in neonatology

    NASA Astrophysics Data System (ADS)

    Rehberger, Matthias; Giovannella, Martina; Pagliazzi, Marco; Weigel, Udo; Durduran, Turgut; Contini, Davide; Spinelli, Lorenzo; Pifferi, Antonio; Torricelli, Alessandro; Schmitt, Robert

    2015-07-01

    Improved cerebral monitoring systems are needed to prevent preterm infants from long-term cognitive and motor restrictions. Combining advanced near-infrared diffuse spectroscopy measurement technologies, time-resolved spectroscopy (TRS) and diffuse correlation spectroscopy (DCS) will introduce novel indicators of cerebral oxygen metabolism and blood flow for neonatology. For non-invasive sensing a fiber-optical probe is used to send and receive light from the infant head. In this study we introduce a new fiber-based hybrid probe that is designed for volume production. The probe supports TRS and DCS measurements in a cross geometry, thus both technologies gain information on the same region inside the tissue. The probe is highly miniaturized to perform cerebral measurements on heads of extreme preterm infants down to head diameters of 6cm. Considerations concerning probe production focus on a reproducible accuracy in shape and precise optical alignment. In this way deviations in measurement data within a series of probes should be minimized. In addition to that, requirements for clinical use like robustness and hygiene are considered. An additional soft-touching sleeve made of FDA compatible silicone allows for a flexible attachment with respect to the individual anatomy of each patient. We present the technical concept of the hybrid probe and corresponding manufacturing methods. A prototype of the probe is shown and tested on tissue phantoms as well as in vivo to verify its operational reliability.

  14. Synthesis and optical characterization of interactive nanosystems

    NASA Astrophysics Data System (ADS)

    Yasmin, Zannatul

    The use of interactive nanosystems (INSs) has unique advantages in sensing applications. Due to their multivalent interactions and stimuli responsiveness i.e. chemical, optical, pH, these adaptive networks can enhance sensing applications. In this work, two distinct INSs are synthesized and the interparticle interactions are probed optically. One of them is the gold nanoparticles based INS in presence of the biomolecule, glutathione. Their unique optical properties and surface binding affinity to thiol-containing glutathione provide an intriguing opportunity to probe bio-systems. The second one is the rare earth oxides/fluorides conjugated with gold nanoparticles based INS which exhibit tunabilty in their multi-wavelength absorbance and emission through coupling with the surface plasmon resonance of gold nanoparticles. The conjugation of these two interactive particles is uniquely synthesized in the presence of the bio-polymer chitosan. This structure displays tunable optical properties. The two novel INSs presented are characterized through their optical signatures using various spectroscopies including a novel approach developed in this work that comprises an all optical photoacoustic spectroscopy (AOPAS). The AOPAS technique is used to determine the unique characteristics of these INSs in aqueous environments by measuring their optical properties in situ. Additionally, we expect the AOPAS technique will provide unique information about nano-bio interfaces and the usefulness of INS as sensors in biological systems without the artifacts limiting the use of current methods, such as fluorescence-based indicators.

  15. Non-invasive ventilation in acute respiratory failure in children

    PubMed Central

    Abadesso, Clara; Nunes, Pedro; Silvestre, Catarina; Matias, Ester; Loureiro, Helena; Almeida, Helena

    2012-01-01

    The aim of this paper is to assess the clinical efficacy of non-invasive ventilation (NIV) in avoiding endotracheal intubation (ETI), to demonstrate clinical and gasometric improvement and to identify predictive risk factors associated with NIV failure. An observational prospective clinical study was carried out. Included Patients with acute respiratory disease (ARD) treated with NIV, from November 2006 to January 2010 in a Pediatric Intensive Care Unit (PICU). NIV was used in 151 patients with acute respiratory failure (ARF). Patients were divided in two groups: NIV success and NIV failure, if ETI was required. Mean age was 7.2±20.3 months (median: 1 min: 0,3 max.: 156). Main diagnoses were bronchiolitis in 102 (67.5%), and pneumonia in 44 (29%) patients. There was a significant improvement in respiratory rate (RR), heart rate (HR), pH, and pCO2 at 2, 6, 12 and 24 hours after NIV onset (P<0.05) in both groups. Improvement in pulse oximetric saturation/fraction of inspired oxygen (SpO2/FiO2) was verified at 2, 4, 6, 12 and 24 hours after NIV onset in the success group (P<0.001). In the failure group, significant SpO2/FiO2 improvement was only observed in the first 4 hours. NIV failure occurred in 34 patients (22.5%). Risk factors for NIV failure were apnea, prematurity, pneumonia, and bacterial co-infection (P<0.05). Independent risk factors for NIV failure were apneia (P<0.001; odds ratio 15.8; 95% confidence interval: 3.42–71.4) and pneumonia (P<0.001, odds ratio 31.25; 95% confidence interval: 8.33–111.11). There were no major complications related with NIV. In conclusion this study demonstrates the efficacy of NIV as a form of respiratory support for children and infants with ARF, preventing clinical deterioration and avoiding ETI in most of the patients. Risk factors for failure were related with immaturity and severe infection. PMID:22802994

  16. Infrared irradiation of skin for the development of non-invasive health monitoring technologies

    NASA Astrophysics Data System (ADS)

    Abdussamad Abbas, Hisham; Triplett, Gregory

    2015-06-01

    Infrared radiation was employed to study the optical transmission properties of pigskin and the factors that influence transmission at room temperature. The skin samples from the forehead of piglets were irradiated using an infrared-pulsed source by varying the beam properties such as optical power, power density, duty cycle, as well as sample thickness. Because infrared radiation in select instances can penetrate through thick-fleshy skin more easily than visible radiation, temperature fluctuations observed within the skin samples stemming from exposure-dependent absorption revealed interesting transmission properties and the limits of optical exposure. Pigskin was selected for this study since its structure most closely resembles that of human skin. Furthermore, the pulsed beam technique compared to continuous operation offers more precise control of heat generation within the skin. Through this effort, the correlated pulsed-beam parameters that influence infrared transmission were identified and varied to minimize the internal absorption losses through the dermis layers. The two most significant parameters that reduce absorption losses were frequency and duty cycle of the pulsed beam. Using the Bouger-Beer-Lambert Law, the absorption coefficient from empirical data is approximated, while accepting that the absorption coefficient is neither uniform nor linear. Given that the optical source used in this study was single mode, the infrared spectra obtained from irradiated samples also reveal characteristics of the skin structure. Realization of appropriate sample conditions and exposure parameters that reduce light attenuation within the skin and sample degradation could give way to novel non-invasive measuring techniques for health monitoring purposes.

  17. Optical Characterization of Molecular Contaminant Films

    NASA Technical Reports Server (NTRS)

    Visentine, James T.

    2007-01-01

    A semi-empirical method of optical characterization of thin contaminant films on surfaces of optical components has been conceived. The method was originally intended for application to films that become photochemically deposited on such optical components as science windows, lenses, prisms, thinfilm radiators, and glass solar-cell covers aboard spacecraft and satellites in orbit. The method should also be applicable, with suitable modifications, to thin optical films (whether deposited deliberately or formed as contaminants) on optical components used on Earth in the computer microchip laser communications and thin-film industries. The method is expected to satisfy the need for a means of understanding and predicting the reductions in spectral transmittance caused by contaminant films and the consequent deterioration of performances of sensitive optical systems. After further development, this method could become part of the basis of a method of designing optical systems to minimize or compensate for the deleterious effects of contaminant films. In the original outer-space application, these deleterious effects are especially pronounced because after photochemical deposition, the films become darkened by further exposure to solar vacuum ultraviolet (VUV) radiation. In this method, thin contaminant films are theoretically modeled as thin optical films, characterized by known or assumed values of thickness, index of refraction, and absorption coefficient, that form on the outer surfaces of the original antireflection coating on affected optical components. The assumed values are adjusted as needed to make actual spectral transmittance values approximate observed ones as closely as possible and to correlate these values with amounts of VUV radiation to which the optical components have been exposed. In an initial study, the method was applied in correlating measured changes in transmittance of high-purity fused silica photochemically coated with silicone films of

  18. Optical characterization of amber from Chiapas, Mexico

    NASA Astrophysics Data System (ADS)

    López-Morales, Guadalupe; Espinosa-Luna, Rafael; Frausto-Reyes, Claudio

    2013-09-01

    An optical characterization of amber samples from México, the Baltic Sea and fake samples is presented, with the aim of discriminate between genuine and fake samples. We sought to identify the physical variables that could serve as the basis for the development of a device whose operation was able to discriminate between samples of genuine and fake amber. The optical refractive index was determined by Spectroscopic Ellipsometry, Abbe refractometry, and by the Brewster angle. The Raman spectra and the fluorescence optical responses were also determined. The results obtained indicate that the refractive index is not a robust variable that can differentiate between genuine amber and a fake sample. On the other hand, the Raman spectra and the fluorescence responses provide information that allows discriminating between both types of samples. For this reason, we used the results obtained by fluorescence as a basis for the design and construction of a prototype simple, reliable, portable, and affordable for authentication of the Mexican amber.

  19. Characterization and simulation of optical sensors.

    PubMed

    Grapinet, M; De Souza, Ph; Smal, J-C; Blosseville, J-M

    2013-11-01

    Numerical simulation is gradually becoming an advantage in active safety. This is why the development of realistic numerical models enabling to substitute real truth by simulated truth is primordial. In order to provide an accurate and cost effective solution to simulate real optical sensor behavior, the software Pro-SiVIC™ has been developed. Simulations with the software Pro-SiVIC™ can replace real tests with optical sensors and hence allow substantial cost and time savings during the development of solutions for driver assistance systems. An optical platform has been developed by IFSTTAR (French Institute of Science and Technology for Transport, Development and Networks) to characterize and validate any existing camera, in order to measure their characteristics as distortion, vignetting, focal length, etc. By comparing real and simulated sensors with this platform, this paper demonstrates that Pro-SiVIC™ accurately reproduces real sensors' behavior. PMID:23735581

  20. Non-invasive Foetal ECG – a Comparable Alternative to the Doppler CTG?

    PubMed Central

    Reinhard, J.; Louwen, F.

    2012-01-01

    This review discusses the alternative of using the non-invasive foetal ECG compared with the conventionally used Doppler CTG. Non-invasive abdominal electrocardiograms (ECG) have been approved for clinical routine since 2008; subsequently they were also approved for antepartum and subpartum procedures. The first study results have been published. Non-invasive foetal ECG is especially indicated during early pregnancy, while the Doppler CTG is recommended for the vernix period. Beyond the vernix period no difference has been recorded in the success rate of either approach. The foetal ECG signal quality is independent of the BMI, whereas the success rate of the Doppler CTG is diminished with an increased BMI. During the first stage of labour, non-invasive foetal ECG demonstrates better signal quality; however during the second stage of labour no difference has been identified between the methods. PMID:25308981

  1. [Options for non-invasive assessment of liver fibrosis based on clinical data].

    PubMed

    Egresi, Anna; Lengyel, Gabriella; Hagymási, Krisztina

    2015-01-11

    Liver cirrhosis is one of the leading causes of death worldwide. Liver biopsy is considered as the gold standard for the diagnosis of chronic liver diseases. Studies have focused on non-invasive markers for liver fibrosis because of the dangers and complications of liver biopsy. The authors review the non-invasive direct as well as indirect methods for liver fibrosis assessment and present the positive and negative predictive value, sensitivity and specificity of those. Clinical utilities of transient elastography (Fibrsocan) is also reviewed. Non-invasive methods are useful in the assessment of liver fibrosis, monitoring disease progression and therapeutic response. Their accuracy can be increased by the combined or sequential use of non-invasive markers. PMID:25563681

  2. Production, Characterization, and Acceleration of Optical Microbunches

    SciTech Connect

    Sears, Christopher M.S.

    2008-06-20

    Optical microbunches with a spacing of 800 nm have been produced for laser acceleration research. The microbunches are produced using a inverse Free-Electron-Laser (IFEL) followed by a dispersive chicane. The microbunched electron beam is characterized by coherent optical transition radiation (COTR) with good agreement to the analytic theory for bunch formation. In a second experiment the bunches are accelerated in a second stage to achieve for the first time direct net acceleration of electrons traveling in a vacuum with visible light. This dissertation presents the theory of microbunch formation and characterization of the microbunches. It also presents the design of the experimental hardware from magnetostatic and particle tracking simulations, to fabrication and measurement of the undulator and chicane magnets. Finally, the dissertation discusses three experiments aimed at demonstrating the IFEL interaction, microbunch production, and the net acceleration of the microbunched beam. At the close of the dissertation, a separate but related research effort on the tight focusing of electrons for coupling into optical scale, Photonic Bandgap, structures is presented. This includes the design and fabrication of a strong focusing permanent magnet quadrupole triplet and an outline of an initial experiment using the triplet to observe wakefields generated by an electron beam passing through an optical scale accelerator.

  3. Characterizing single atom optical dipole traps

    NASA Astrophysics Data System (ADS)

    Shih, Chung-Yu; Gibbons, Michael; Chapman, Michael

    2012-06-01

    Trapping and manipulating individual neutral atoms in far off-resonant traps (FORTs) is a promising approach for quantum information processing. It is important to characterize the trapping environment of the atom and the atomic level shifts due to the trapping fields. Using non-destructive measurement techniques,ootnotetextM. J. Gibbons et al., Phys. Rev. Lett 106, 133002 (2011). we have measured the level dependent AC Stark shifts, trap frequencies, and temperature of single rubidium atoms confined in optical dipole trap.

  4. Non-invasive mechanical properties estimation of embedded objects using tactile imaging sensor

    NASA Astrophysics Data System (ADS)

    Saleheen, Firdous; Oleksyuk, Vira; Sahu, Amrita; Won, Chang-Hee

    2013-05-01

    Non-invasive mechanical property estimation of an embedded object (tumor) can be used in medicine for characterization between malignant and benign lesions. We developed a tactile imaging sensor which is capable of detecting mechanical properties of inclusions. Studies show that stiffness of tumor is a key physiological discerning parameter for malignancy. As our sensor compresses the tumor from the surface, the sensing probe deforms, and the light scatters. This forms the tactile image. Using the features of the image, we can estimate the mechanical properties such as size, depth, and elasticity of the embedded object. To test the performance of the method, a phantom study was performed. Silicone rubber balls were used as embedded objects inside the tissue mimicking substrate made of Polydimethylsiloxane. The average relative errors for size, depth, and elasticity were found to be 67.5%, 48.2%, and 69.1%, respectively. To test the feasibility of the sensor in estimating the elasticity of tumor, a pilot clinical study was performed on twenty breast cancer patients. The estimated elasticity was correlated with the biopsy results. Preliminary results show that the sensitivity of 67% and the specificity of 91.7% for elasticity. Results from the clinical study suggest that the tactile imaging sensor may be used as a tumor malignancy characterization tool.

  5. Transcranial MR-guided High Intensity Focused Ultrasound for Non-Invasive Functional Neurosurgery

    NASA Astrophysics Data System (ADS)

    Werner, Beat; Morel, Anne; Zadicario, Eyal; Jeanmonod, Daniel; Martin, Ernst

    2010-03-01

    While the development of transcranial MR-guided High Intensity Focused Ultrasound has been driven mainly by applications for tumor ablation this new intervention method is also very attractive for functional neurosurgery due to its non-invasiveness, the absence of ionizing radiation and the closed-loop intervention control by MRI. Here we provide preliminary data to demonstrate the clinical feasibility, safety and precision of non-invasive functional neurosurgery by transcranial MR-guided High Intensity Focused Ultrasound.

  6. Non-invasive estimation of thermal tissue properties by high-intensity focused ultrasound

    NASA Astrophysics Data System (ADS)

    Appanaboyina, Sunil; Partanen, Ari; Haemmerich, Dieter

    2013-02-01

    Magnetic Resonance guided High-intensity Focused Ultrasound (MR-HIFU) can be used to locally heat tissue while non-invasively monitoring tissue temperature via MR-based thermometry. The goal of this study was to investigate the use of a computational technique based on inverse heat-transfer modeling for the non-invasive measurement of thermal tissue properties from data collected using an MR-HIFU system.

  7. Estimating Trabecular Bone Mechanical Properties From Non-Invasive Imaging

    NASA Technical Reports Server (NTRS)

    Hogan, Harry A.; Webster, Laurie

    1997-01-01

    An important component in developing countermeasures for maintaining musculoskeletal integrity during long-term space flight is an effective and meaningful method of monitoring skeletal condition. Magnetic resonance imaging (MRI) is an attractive non-invasive approach because it avoids the exposure to radiation associated with X-ray based imaging and also provides measures related to bone microstructure rather than just density. The purpose of the research for the 1996 Summer Faculty Fellowship period was to extend the usefulness of the MRI data to estimate the mechanical properties of trabecular bone. The main mechanical properties of interest are the elastic modulus and ultimate strength. Correlations are being investigated between these and fractal analysis parameters, MRI relaxation times, apparent densities, and bone mineral densities. Bone specimens from both human and equine donors have been studied initially to ensure high-quality MR images. Specimens were prepared and scanned from human proximal tibia bones as well as the equine distal radius. The quality of the images from the human bone appeared compromised due to freezing artifact, so only equine bone was included in subsequent procedures since these specimens could be acquired and imaged fresh before being frozen. MRI scans were made spanning a 3.6 cm length on each of 5 equine distal radius specimens. The images were then sent to Dr. Raj Acharya of the State University of New York at Buffalo for fractal analysis. Each piece was cut into 3 slabs approximately 1.2 cm thick and high-resolution contact radiographs were made to provide images for comparing fractal analysis with MR images. Dual energy X-ray absorptiometry (DEXA) scans were also made of each slab for subsequent bone mineral density determination. Slabs were cut into cubes for mechanical using a slow-speed diamond blade wafering saw (Buehler Isomet). The dimensions and wet weights of each cube specimen were measured and recorded. Wet weights

  8. Application of Raman spectroscopy in Andrology: non-invasive analysis of tissue and single cell

    PubMed Central

    Liu, Yufei; Zhu, Yong

    2014-01-01

    As a fast, label-free and non-invasive detection method, Raman spectroscopy has been widely used for the interrogation of biological tissues, any alterations of molecular structure and chemical components during pathological processes would be identified and revealed via the differences on Raman spectrum. In clinics, the Raman spectroscopy has great potentials to provide real-time scanning of living tissues and fast diagnosis of diseases, just like discrimination of various carcinomas. A portable Raman spectroscopy which combined Raman system with an optical fiber probe has also been developed and proved to be able to provide intraoperative assistance in both human study and animal models. In Andrology, interests in Raman spectroscopy had just emerged. In this review, we summarized the progress about the utility of Raman spectroscopy in Andrology, the literatures were gathered from PubMed and Ovid database using MeSH terms associated with prostate, testis, seminal plasma and single sperm cell. We also highlighted the serious challenges as to the final clinical application of Raman technique. In conclusion, research in Raman spectroscopy may herald a new era for Andrology. PMID:26816760

  9. Non-invasive investigation on a VI century purple codex from Brescia, Italy.

    PubMed

    Aceto, Maurizio; Idone, Ambra; Agostino, Angelo; Fenoglio, Gaia; Gulmini, Monica; Baraldi, Pietro; Crivello, Fabrizio

    2014-01-01

    Purple codices are among the most relevant and prestigious book productions of Late Antique and Medieval age. They usually contained texts from Holy Writings written with golden or silver inks on parchment dyed in a purple hue. According to the tradition, the colour of parchment was obtained by the well renowned Tyrian purple dye. From the material point of view, however, very little is known about the compounds actually used in the manufacture of these manuscripts. Presently, the information available is limited to the ancient art treatises, with very few diagnostic evidences supporting them and, moreover, none confirming the presence of Tyrian purple. It is more than apparent, then, the need to have at disposal larger and more complete information at the concern, in order to verify what came to us from the literary tradition only. In this study, preliminary results are presented from non-invasive investigation on a VI century purple codex, the so-called CodexBrixianus, held in the Biblioteca Civica Queriniana at Brescia (Italy). Analyses were carried out with XRF spectrometry, UV-visible diffuse reflectance spectrophotometry, molecular spectrofluorimetry and optical microscopy. The results suggest the hypothesis that Tyrian purple had been used as a minor component mixed with other less precious dyes such as folium or orchil. PMID:23981412

  10. Non-invasive investigation on a VI century purple codex from Brescia, Italy

    NASA Astrophysics Data System (ADS)

    Aceto, Maurizio; Idone, Ambra; Agostino, Angelo; Fenoglio, Gaia; Gulmini, Monica; Baraldi, Pietro; Crivello, Fabrizio

    2014-01-01

    Purple codices are among the most relevant and prestigious book productions of Late Antique and Medieval age. They usually contained texts from Holy Writings written with golden or silver inks on parchment dyed in a purple hue. According to the tradition, the colour of parchment was obtained by the well renowned Tyrian purple dye. From the material point of view, however, very little is known about the compounds actually used in the manufacture of these manuscripts. Presently, the information available is limited to the ancient art treatises, with very few diagnostic evidences supporting them and, moreover, none confirming the presence of Tyrian purple. It is more than apparent, then, the need to have at disposal larger and more complete information at the concern, in order to verify what came to us from the literary tradition only. In this study, preliminary results are presented from non-invasive investigation on a VI century purple codex, the so-called CodexBrixianus, held in the Biblioteca Civica Queriniana at Brescia (Italy). Analyses were carried out with XRF spectrometry, UV-visible diffuse reflectance spectrophotometry, molecular spectrofluorimetry and optical microscopy. The results suggest the hypothesis that Tyrian purple had been used as a minor component mixed with other less precious dyes such as folium or orchil.

  11. Non-invasive detection of periodontal disease using diffuse reflectance spectroscopy: a clinical study

    NASA Astrophysics Data System (ADS)

    Prasanth, Chandra Sekhar; Betsy, Joseph; Subhash, Narayanan; Jayanthi, Jayaraj L.; Prasanthila, Janam

    2012-03-01

    In clinical diagnostic procedures, gingival inflammation is considered as the initial stage of periodontal breakdown. This is often detected clinically by bleeding on probing as it is an objective measure of inflammation. Since conventional diagnostic procedures have several inherent drawbacks, development of novel non-invasive diagnostic techniques assumes significance. This clinical study was carried out in 15 healthy volunteers and 25 patients to demonstrate the applicability of diffuse reflectance (DR) spectroscopy for quantification and discrimination of various stages of inflammatory conditions in periodontal disease. The DR spectra of diseased lesions recorded using a point monitoring system consisting of a tungsten halogen lamp and a fiber-optic spectrometer showed oxygenated hemoglobin absorption dips at 545 and 575 nm. Mean DR spectra on normalization shows marked differences between healthy and different stages of gingival inflammation. Among the various DR intensity ratios investigated, involving oxy Hb absorption peaks, the R620/R575 ratio was found to be a good parameter of gingival inflammation. In order to screen the entire diseased area and its surroundings instantaneously, DR images were recorded with an EMCCD camera at 620 and 575 nm. We have observed that using the DR image intensity ratio R620/R575 mild inflammatory tissues could be discriminated from healthy with a sensitivity of 92% and specificity of 93%, and from moderate with a sensitivity of 83% and specificity of 96%. The sensitivity and specificity obtained between moderate and severe inflammation are 82% and 76% respectively.

  12. Non-Invasive Beam Detection in a High-Average Power Electron Accelerator

    SciTech Connect

    Williams, J.; Biedron, S.; Harris, J.; Martinez, J.; Milton, S. V.; Van Keuren, J.; Benson, Steve V.; Evtushenko, Pavel; Neil, George R.; Zhang, Shukui

    2013-12-01

    For a free-electron laser (FEL) to work effectively the electron beam quality must meet exceptional standards. In the case of an FEL operating at infrared wavelengths in an amplifier configuration the critical phase space tends to be in the longitudinal direction. Achieving high enough longitudinal phase space density directly from the electron injector system of such an FEL is difficult due to space charge effects, thus one needs to manipulate the longitudinal phase space once the beam energy reaches a sufficiently high value. However, this is fraught with problems. Longitudinal space charge and coherent synchrotron radiation can both disrupt the overall phase space, furthermore, the phase space disruption is exacerbated by the longitudinal phase space manipulation process required to achieve high peak current. To achieve and maintain good FEL performance one needs to investigate the longitudinal emittance and be able to measure it during operation preferably in a non-invasive manner. Using the electro-optical sampling (EOS) method, we plan to measure the bunch longitudinal profile of a high-energy (~120-MeV), high-power (~10kW or more FEL output power) beam.

  13. Non-invasive single-shot imaging through scattering layers and around corners via speckle correlations

    NASA Astrophysics Data System (ADS)

    Katz, Ori; Heidmann, Pierre; Fink, Mathias; Gigan, Sylvain

    2014-10-01

    Optical imaging through and inside complex samples is a difficult challenge with important applications in many fields. The fundamental problem is that inhomogeneous samples such as biological tissue randomly scatter and diffuse light, preventing the formation of diffraction-limited images. Despite many recent advances, no current method can perform non-invasive imaging in real-time using diffused light. Here, we show that, owing to the ‘memory-effect’ for speckle correlations, a single high-resolution image of the scattered light, captured with a standard camera, encodes sufficient information to image through visually opaque layers and around corners with diffraction-limited resolution. We experimentally demonstrate single-shot imaging through scattering media and around corners using spatially incoherent light and various samples, from white paint to dynamic biological samples. Our single-shot lensless technique is simple, does not require wavefront-shaping nor time-gated or interferometric detection, and is realized here using a camera-phone. It has the potential to enable imaging in currently inaccessible scenarios.

  14. Non-invasive Energy Spread monitoring for the JLAB Experimental Program Via SLI's

    SciTech Connect

    Arne Freyberger

    2005-03-19

    The hypernuclear physics program at Jefferson Lab [JLAB] requires a tight upper limit on the RMS beam energy spread of sigmaE over E < 3 x 10{sup -5}. The energy spread is determined by measuring the beam width at a dispersive location (D {approx} 4 m) in the transport line to the experimental halls. Ignoring the intrinsic beam size, this low energy spread corresponds to an upper bound on the beam width of sigma{sub beam} < 120 mu-m. Such small beam sizes cannot be measured using direct imaging of the synchrotron light due to diffraction limitations. Using interferometry of the synchrotron light the resolution of the optical system can be made very high. The non-invasive nature of this measurement is also very advantageous as it allows continuous energy spread monitoring. Two synchrotron light interferometers have been built and installed at Jefferson Lab, one each in the Hall-A and Hall-C transport lines. The two devices operate over a beam current range from 10 to 120 mu-A and have a spatial resolution better than 10 mu-m. The structure of the interferometer, the experience gained during its installation, beam measurements and energy spread stability are presented.

  15. Non-invasive PET Imaging of PARP1 Expression in Glioblastoma Models

    PubMed Central

    Carney, Brandon; Carlucci, Giuseppe; Salinas, Beatriz; Di Gialleonardo, Valentina; Kossatz, Susanne; Vansteene, Axel; Longo, Valerie A.; Bolaender, Alexander; Chiosis, Gabriela; Keshari, Kayvan R.; Weber, Wolfgang A.; Reiner, Thomas

    2015-01-01

    Purpose The current study presents [18F]PARPi as imaging agent for PARP1 expression. Procedures [18F]PARPi was generated by conjugating a 2H-phthalazin-1-one scaffold to 4-[18F]fluorobenzoic acid. Biochemical assays, optical in vivo competition, biodistribution analysis, positron emission tomography (PET)/X-ray computed tomography, and PET/ magnetic resonance imaging studies were performed in subcutaneous and orthotopic mouse models of glioblastoma. Results [18F]PARPi shows suitable pharmacokinetic properties for brain tumor imaging (IC50=2.8±1.1 nM; logPCHI=2.15±0.41; plasma-free fraction=63.9±12.6 %) and accumulates selectively in orthotopic brain tumor tissue. Tracer accumulation in subcutaneous brain tumors was 1.82±0.21 %ID/g, whereas in healthy brain, the uptake was only 0.04±0.01 %ID/g. Conclusions [18F]PARPi is a selective PARP1 imaging agent that can be used to visualize glioblastoma in xenograft and orthotopic mouse models with high precision and good signal/noise ratios. It offers new opportunities to non-invasively image tumor growth and monitor interventions. PMID:26493053

  16. Using Non-Invasive Multi-Spectral Imaging to Quantitatively Assess Tissue Vasculature

    SciTech Connect

    Vogel, A; Chernomordik, V; Riley, J; Hassan, M; Amyot, F; Dasgeb, B; Demos, S G; Pursley, R; Little, R; Yarchoan, R; Tao, Y; Gandjbakhche, A H

    2007-10-04

    This research describes a non-invasive, non-contact method used to quantitatively analyze the functional characteristics of tissue. Multi-spectral images collected at several near-infrared wavelengths are input into a mathematical optical skin model that considers the contributions from different analytes in the epidermis and dermis skin layers. Through a reconstruction algorithm, we can quantify the percent of blood in a given area of tissue and the fraction of that blood that is oxygenated. Imaging normal tissue confirms previously reported values for the percent of blood in tissue and the percent of blood that is oxygenated in tissue and surrounding vasculature, for the normal state and when ischemia is induced. This methodology has been applied to assess vascular Kaposi's sarcoma lesions and the surrounding tissue before and during experimental therapies. The multi-spectral imaging technique has been combined with laser Doppler imaging to gain additional information. Results indicate that these techniques are able to provide quantitative and functional information about tissue changes during experimental drug therapy and investigate progression of disease before changes are visibly apparent, suggesting a potential for them to be used as complementary imaging techniques to clinical assessment.

  17. In vivo carbon nanotube-enhanced non-invasive photoacoustic mapping of the sentinel lymph node

    NASA Astrophysics Data System (ADS)

    Pramanik, Manojit; Song, Kwang Hyun; Swierczewska, Magdalena; Green, Danielle; Sitharaman, Balaji; Wang, Lihong V.

    2009-06-01

    Sentinel lymph node biopsy (SLNB), a less invasive alternative to axillary lymph node dissection (ALND), has become the standard of care for patients with clinically node-negative breast cancer. In SLNB, lymphatic mapping with radio-labeled sulfur colloid and/or blue dye helps identify the sentinel lymph node (SLN), which is most likely to contain metastatic breast cancer. Even though SLNB, using both methylene blue and radioactive tracers, has a high identification rate, it still relies on an invasive surgical procedure, with associated morbidity. In this study, we have demonstrated a non-invasive single-walled carbon nanotube (SWNT)-enhanced photoacoustic (PA) identification of SLN in a rat model. We have successfully imaged the SLN in vivo by PA imaging (793 nm laser source, 5 MHz ultrasonic detector) with high contrast-to-noise ratio (=89) and good resolution (~500 µm). The SWNTs also show a wideband optical absorption, generating PA signals over an excitation wavelength range of 740-820 nm. Thus, by varying the incident light wavelength to the near infrared region, where biological tissues (hemoglobin, tissue pigments, lipids and water) show low light absorption, the imaging depth is maximized. In the future, functionalization of the SWNTs with targeting groups should allow the molecular imaging of breast cancer.

  18. A novel, microscope based, non invasive Laser Doppler flowmeter for choroidal blood flow assessment

    PubMed Central

    Strohmaier, C; Werkmeister, RM; Bogner, B; Runge, C; Schroedl, F; Brandtner, H; Radner, W; Schmetterer, L; Kiel, JW; Grabnerand, G; Reitsamer, HA

    2015-01-01

    Impaired ocular blood flow is involved in the pathogenesis of numerous ocular diseases like glaucoma or AMD. The purpose of the present study was to introduce and validate a novel, microscope based, non invasive laser Doppler flowmeter (NILDF) for measurement of blood flow in the choroid. The custom made NI-LDF was compared with a commercial fiber optic based laser Doppler flowmeter (Perimed PF4000). Linearity and stability of the NI-LDF were assessed in a silastic tubing model (i.d. 0.3 mm) at different flow rates (range 0.4 – 3 ml/h). In a rabbit model continuous choroidal blood flow measurements were performed with both instruments simultaneously. During blood flow measurements ocular perfusion pressure was changed by manipulations of intraocular pressure via intravitreal saline infusions. The NILDF measurement correlated linearly to intraluminal flow rates in the perfused tubing model (r = 0.99, p<0.05) and remained stable during a 1 hour measurement at a constant flow rate. Rabbit choroidal blood flow measured by the PF4000 and the NI-LDF linearly correlated with each other over the entire measurement range (r = 0.99, y = x* 1,01 – 12,35 P.U., p < 0,001). In conclusion, the NI-LDF provides valid, semi quantitative measurements of capillary blood flow in comparison to an established LDF instrument and is suitable for measurements at the posterior pole of the eye. PMID:21443871

  19. Non-Invasive Beam Detection in a High-Average Power Electron Accelerator

    NASA Astrophysics Data System (ADS)

    Williams, Joel; Biedron, Sandra; Harris, John; Martinez, Jorge; Milton, Stephen; Benson, S.; Evtushenko, P.; Neil, G.; Zhang, S.

    2014-03-01

    For a free-electron laser (FEL) to work effectively the electron beam quality must meet exceptional standards. In the case of an FEL operating at infrared wavelengths the critical phase space tends to be in the longitudinal direction. Achieving high enough longitudinal phase space density directly from the electron injector system in an FEL is difficult due to space charge effects, thus one needs to manipulate the longitudinal phase space once the beam energy reaches a sufficiently high value. However, this is fraught with problems. Longitudinal space charge and coherent synchrotron radiation can both disrupt the overall phase space, furthermore, the phase space disruption is exacerbated by the longitudinal phase space manipulation process required to achieve high peak current. To achieve and maintain good FEL performance, one needs to investigate the longitudinal emittance during operation, preferably in a non-invasive manner. Using electro-optical (EO) methods, we plan to measure the bunch longitudinal profile of an energy (~120-MeV), high-power (~10 kW or more average FEL output power) beam. Such a diagnostic could be critical in efforts to diagnose and help mitigate deleterious beam effects for high output power FELs.

  20. Development of a FBG probe for non-invasive carotid pulse waveform assessment

    NASA Astrophysics Data System (ADS)

    Leitão, C.; Bilro, L.; Alberto, N.; Antunes, P.; Lima, H.; André, P. S.; Nogueira, R.; Pinto, J. L.

    2012-06-01

    One of the early predictors of cardiovascular diseases, with growing interest, is the arterial stiffness which is typically evaluated through the velocity and morphology of the arterial pressure wave. In each cardiac cycle the heart generates a pressure wave which propagates through the arterial tree. Along its path, the pressure wave interacts with the arterial walls and, consequently, the morphology of a local arterial pressure wave can be assessed by the arterial distention movement. Due to its superficiality, proximity of the heart and high probability of atherosclerosis development, the carotid artery has particular interest to be monitored. In this work, the development of a non-invasive fibre Bragg grating (FBG) probe for the acquisition of the arterial distention wave is presented. Comparing to traditional methods, optical FBG based sensors can offer many advantages, namely, compactness, immunity to electromagnetic interference, high sensitivity, low noise and immunity to light source intensity due to its codification in the wavelength domain. The arterial movements induce strain on a uniform FBG, with the arterial distention pattern. The carotid pulse wave was successful accessed in young human carotid artery, with an acquisition rate of 950 Hz, allowing a clear distinction of the carotid pulse identification points.

  1. Non-invasive NIR spectroscopy of human brain function during exercise.

    PubMed

    Perrey, Stéphane

    2008-08-01

    The assessment of physiological changes associated with brain activity has become possible by optical methods, such as near-infrared spectroscopy (NIRS). NIRS is a useful neuroimaging technique based on haemodynamic principles for the non-invasive investigation of brain in motion. Due to its properties, the near-infrared light can penetrate biological tissue reasonably well to assess brain activity and two types of measurements are possible according to the number of channels used: dynamic changes in a localized brain region or functional brain imaging. The theoretical and technological advances of the past 10-15 years have opened the door to a range of applications in the human movement sciences, including some that involve imaging of the adult brain during motor and cognitive tasks, which for many years had been inaccessible to NIRS. This article examines the perturbation methods for measuring cerebral haemodynamic responses within resting and exercise conditions in humans and how NIRS can be used to image the moving brain. Methodological challenges of NIRS technique are presented, while the advantages and pitfalls of NIRS compared to other neuroimaging methods are discussed. Actual and future uses for NIRS in the field of sport sciences are outlined for a better understanding of brain processes during movement. PMID:18539160

  2. Picosecond acoustics in vegetal cells: non invasive in vitro measurements at a sub-cell scale

    NASA Astrophysics Data System (ADS)

    Audoin, Bertrand; Rossignol, Clément; Chigarev, Nikolay; Ducousso, Mathieu; Forget, Guillaume; Guillemot, Fabien; Durrieu, Marie-Christine

    2010-01-01

    A 100 fs laser pulse passes through a single transparent cell and is absorbed at the surface of a metallic substrate. Picosecond acoustic waves are generated and propagate through the cell in contact with the metal. Interaction of the high frequency acoustic pulse with a probe laser light gives rise to stimulated Brillouin oscillations. The measurements are thus made with lasers for both the opto-acoustic generation and the acousto-optic detection. The technique offers perspectives for single cell imaging. The in plane resolution is limited by the pump and probe spot sizes, i.e ˜1 μm, and the in depth resolution is provided by the acoustic frequencies, typically in the GHz range. The effect of the technique on cell safety is discussed. Experiments achieved in vegetal cells illustrate reproducibility and sensitivity of the measurements. The acoustic responses of cell organelles are significantly different. The results support the potentialities of the hypersonic non invasive technique in the fields of bio-engineering and medicine.

  3. Plasma surface reflectance spectroscopy for non-invasive and continuous monitoring of extracellular component of blood

    NASA Astrophysics Data System (ADS)

    Sakota, Daisuke; Takatani, Setsuo

    2012-04-01

    To achieve the quantitative optical non-invasive diagnosis of blood during extracorporeal circulation therapies, the instrumental technique to extract extracellular spectra from whole blood was developed. In the circuit, the continuous blood flow was generated by a centrifugal blood pump. The oxygen saturation was maintained 100% by an oxygenator. The developed glass optical flow cell was attached to the outlet tubing of the oxygenator. The halogen lamp including the light from 400 to 900 nm wavelength was used for the light source. The light was guided into an optical fiber. The light emitted by the fiber was collimated and emitted to the flow cell flat surface at the incident angle of 45 degrees. The light just reflected on the boundary between inner surface of the flow cell and plasma at 45 degrees was detected by the detection fiber. The detected light was analyzed by a spectral photometer. The obtained spectrum from 400 to 600nm wavelength was not changed with respect to the hematocrit. In contrast, the signal in the spectral range was changed when the plasma free hemoglobin increased. By using two spectral range, 505+/-5 nm and 542.5+/-2.5 nm, the differential spectrum was correlated with the free hemoglobin at R2=0.99. On the other hand, as for the hematocrit, the differential spectrum was not correlated at R2=0.01. Finally, the plasma free hemoglobin was quantified with the accuracy of 22+/-19mg/dL. The result shows that the developed plasma surface reflectance spectroscopy (PSRS) can extract the plasma spectrum from flowing whole blood.

  4. Near-infrared oxymeter biosensor prototype for non-invasive in vivo analysis of rat brain oxygenation: effects of drugs of abuse

    NASA Astrophysics Data System (ADS)

    Crespi, F.; Donini, M.; Bandera, A.; Congestri, F.; Formenti, F.; Sonntag, V.; Heidbreder, C.; Rovati, L.

    2006-07-01

    The feasibility of non-invasive analysis of brain activities was studied in the attempt to overcome the major limitation of actual in vivo methodologies, i.e. invasiveness. Optic fibre probes were used as the optical head of a novel, highly sensitive near-infrared continuous wave spectroscopy (CW-NIR) instrument. This prototype was designed for non-invasive analysis of the two main forms of haemoglobin: oxy-haemoglobin (HbO2) and deoxy-haemoglobin (Hb), chromophores present in biological tissues. It was tested in peripheral tissue (human gastrocnemius muscle) and then reset to perform the measurement on rat brain. In animal studies, the optical head was firmly placed using stereotaxic apparatus upon the sagittal line of the head of anaesthetized adult rats, without any surgery. Then pharmacological treatments with saline (300 µl s.c.) amphetamine (2 mg kg-1) or nicotine (0.4 mg kg-1) were performed. Within 10-20 min amphetamine substantially increased HbO2 and reduced Hb control levels. Nicotine produced a rapid initial increase followed by a decrease in HbO2. In contrast to amphetamine, nicotine treatment also reduced Hb and blood volume. These results support the capacity of our CW-NIR prototype to measure non-invasively HbO2 and Hb levels in the rat brain, that are markers of the degree of tissue oxygenation, thus providing an index of blood levels and therefore of brain metabolism.

  5. Functional photoacoustic tomography for non-invasive imaging of cerebral blood oxygenation and blood volume in rat brain in vivo

    NASA Astrophysics Data System (ADS)

    Wang, Xueding; Xie, Xueyi; Ku, Geng; Stoica, George; Wang, Lihong V.

    2005-04-01

    Based on the multi-wavelength laser-based photoacoustic tomography, non-invasive in vivo imaging of functional parameters, including the hemoglobin oxygen saturation and the total concentration of hemoglobin, in small-animal brains was realized. The high sensitivity of this technique is based on the spectroscopic differences between oxy- and deoxy-hemoglobin while its spatial resolution is bandwidth-limited by the photoacoustic signals rather than by the optical diffusion as in optical imaging. The point-by-point distributions of blood oxygenation and blood volume in the cerebral cortical venous vessels, altered by systemic physiological modulations including hyperoxia, normoxia and hypoxia, were visualized successfully through the intact skin and skull. This technique, with its prominent intrinsic advantages, can potentially accelerate the progress in neuroscience and provide important new insights into cerebrovascular physiology and brain function that are of great significance to the neuroscience community.

  6. Non-invasive, MRI-compatible fibreoptic device for functional near-IR reflectometry of human brain

    SciTech Connect

    Sorvoja, H.S.S.; Myllylae, T S; Myllylae, Risto A; Kirillin, M Yu; Sergeeva, Ekaterina A; Elseoud, A A; Nikkinen, J; Tervonen, O; Kiviniemi, V

    2011-01-24

    A non-invasive device for measuring blood oxygen variations in human brain is designed, implemented, and tested for MRI compatibility. The device is based on principles of near-IR reflectometry; power LEDs serve as sources of probing radiation delivered to patient skin surface through optical fibres. Numerical Monte Carlo simulations of probing radiation propagation in a multilayer brain model are performed to evaluate signal levels at different source - detector separations at three operation wavelengths and an additional wavelength of 915 nm. It is shown that the device can be applied for brain activity studies using power LEDs operating at 830 and 915 nm, while employment of wavelength of 660 nm requires an increased probing power. Employment of the wavelength of 592 nm in the current configuration is unreasonable. (application of lasers and laser-optical methods in life sciences)

  7. Diffuse Optical Characterization of the Healthy Human Thyroid Tissue and Two Pathological Case Studies

    PubMed Central

    Lindner, Claus; Johansson, Johannes; Weigel, Udo M.; Halperin, Irene; Hanzu, Felicia A.; Durduran, Turgut

    2016-01-01

    The in vivo optical and hemodynamic properties of the healthy (n = 22) and pathological (n = 2) human thyroid tissue were measured non-invasively using a custom time-resolved spectroscopy (TRS) and diffuse correlation spectroscopy (DCS) system. Medical ultrasound was used to guide the placement of the hand-held hybrid optical probe. TRS measured the absorption and reduced scattering coefficients (μa, μs′) at three wavelengths (690, 785 and 830 nm) to derive total hemoglobin concentration (THC) and oxygen saturation (StO2). DCS measured the microvascular blood flow index (BFI). Their dependencies on physiological and clinical parameters and positions along the thyroid were investigated and compared to the surrounding sternocleidomastoid muscle. The THC in the thyroid ranged from 131.9 μM to 144.8 μM, showing a 25–44% increase compared to the surrounding sternocleidomastoid muscle tissue. The blood flow was significantly higher in the thyroid (BFIthyroid = 16.0 × 10-9 cm2/s) compared to the muscle (BFImuscle = 7.8 × 10-9 cm2/s), while StO2 showed a small (StO2, muscle = 63.8% to StO2, thyroid = 68.4%), yet significant difference. Two case studies with thyroid nodules underwent the same measurement protocol prior to thyroidectomy. Their THC and BFI reached values around 226.5 μM and 62.8 × 10-9 cm2/s respectively showing a clear contrast to the nodule-free thyroid tissue as well as the general population. The initial characterization of the healthy and pathologic human thyroid tissue lays the ground work for the future investigation on the use of diffuse optics in thyroid cancer screening. PMID:26815533

  8. Diffuse Optical Characterization of the Healthy Human Thyroid Tissue and Two Pathological Case Studies.

    PubMed

    Lindner, Claus; Mora, Mireia; Farzam, Parisa; Squarcia, Mattia; Johansson, Johannes; Weigel, Udo M; Halperin, Irene; Hanzu, Felicia A; Durduran, Turgut

    2016-01-01

    The in vivo optical and hemodynamic properties of the healthy (n = 22) and pathological (n = 2) human thyroid tissue were measured non-invasively using a custom time-resolved spectroscopy (TRS) and diffuse correlation spectroscopy (DCS) system. Medical ultrasound was used to guide the placement of the hand-held hybrid optical probe. TRS measured the absorption and reduced scattering coefficients (μa, μs') at three wavelengths (690, 785 and 830 nm) to derive total hemoglobin concentration (THC) and oxygen saturation (StO2). DCS measured the microvascular blood flow index (BFI). Their dependencies on physiological and clinical parameters and positions along the thyroid were investigated and compared to the surrounding sternocleidomastoid muscle. The THC in the thyroid ranged from 131.9 μM to 144.8 μM, showing a 25-44% increase compared to the surrounding sternocleidomastoid muscle tissue. The blood flow was significantly higher in the thyroid (BFIthyroid = 16.0 × 10-9 cm2/s) compared to the muscle (BFImuscle = 7.8 × 10-9 cm2/s), while StO2 showed a small (StO2, muscle = 63.8% to StO2, thyroid = 68.4%), yet significant difference. Two case studies with thyroid nodules underwent the same measurement protocol prior to thyroidectomy. Their THC and BFI reached values around 226.5 μM and 62.8 × 10-9 cm2/s respectively showing a clear contrast to the nodule-free thyroid tissue as well as the general population. The initial characterization of the healthy and pathologic human thyroid tissue lays the ground work for the future investigation on the use of diffuse optics in thyroid cancer screening. PMID:26815533

  9. High-speed InGaAs thin film MSM photodetector characterization using a fiber-based electro-optic sampling system

    NASA Astrophysics Data System (ADS)

    Seo, Sang-Woo; Cho, Sang-Yeon; Huang, Sa; Brown, April; Jokerst, Nan M.

    2004-06-01

    As optoelectronic devices increase in speed, the measurement system used to characterize these devices must have sufficient bandwidth and minimum parasitic loading during test to accurately determine the intrinsic performance of the device under test. Conventional electrical measurement systems have an intrinsic bandwidth due to the available components for test and have parasitic loading due to direct electrical contact to the device under the test. Electro-optic sampling is an excellent measurement technique for characterizing ultra-fast devices because it has high bandwidth, is non-contact, is non-destructive, and relatively non-invasive. In this paper, an optical fiber-based electro-optic sampling system is designed and used for characterizing high speed InGaAs thin film MSM photodetectors. A fiber laser which is operating at 1556 nm wavelength was used for the sampling and excitation beam. Optical fibers were used to connect each component in the system for flexibility. InGaAs thin film MSM photodetectors were fabricated and characterized. InGaAs thin film MSM photodetectors were bonded onto a coplanar strip line deposited on a benzocyclobutene (BCB)-coated glass substrate for characterization. These thin film photodetectors show high speed operation combined with high responsivity and large detection area compared to P-I-N photodetectors operating at similar speeds

  10. Microwave Radiometry for Non-Invasive Detection of Vesicoureteral Reflux (VUR) Following Bladder Warming.

    PubMed

    Stauffer, Paul R; Maccarini, Paolo F; Arunachalam, Kavitha; De Luca, Valeria; Salahi, Sara; Boico, Alina; Klemetsen, Oystein; Birkelund, Yngve; Jacobsen, Svein K; Bardati, Fernando; Tognolatti, Piero; Snow, Brent

    2011-01-01

    BACKGROUND: Vesicoureteral reflux (VUR) is a serious health problem leading to renal scarring in children. Current VUR detection involves traumatic x-ray imaging of kidneys following injection of contrast agent into bladder via invasive Foley catheter. We present an alternative non-invasive approach for detecting VUR by radiometric monitoring of kidney temperature while gently warming the bladder. METHODS: We report the design and testing of: i) 915MHz square slot antenna array for heating bladder, ii) EMI-shielded log spiral microstrip receive antenna, iii) high-sensitivity 1.375GHz total power radiometer, iv) power modulation approach to increase urine temperature relative to overlying perfused tissues, and v) invivo porcine experiments characterizing bladder heating and radiometric temperature of aaline filled 30mL balloon "kidney" implanted 3-4cm deep in thorax and varied 2-6°C from core temperature. RESULTS: SAR distributions are presented for two novel antennas designed to heat bladder and monitor deep kidney temperatures radiometrically. We demonstrate the ability to heat 180mL saline in in vivo porcine bladder to 40-44°C while maintaining overlying tissues <38°C using time-modulated square slot antennas coupled to the abdomen with room temperature water pad. Pathologic evaluations confirmed lack of acute thermal damage in pelvic tissues for up to three 20min bladder heat exposures. The radiometer clearly recorded 2-6°C changes of 30mL "kidney" targets at depth in 34°C invivo pig thorax. CONCLUSION: A 915MHz antenna array can gently warm in vivo pig bladder without toxicity while a 1.375GHz radiometer with log spiral receive antenna detects ≥2°C rise in 30mL "urine" located 3-4cm deep in thorax, demonstrating more than sufficient sensitivity to detect Grade 4-5 reflux of warmed urine for non-invasive detection of VUR. PMID:22866211

  11. Microwave Radiometry for Non-Invasive Detection of Vesicoureteral Reflux (VUR) Following Bladder Warming

    PubMed Central

    Stauffer, Paul R.; Maccarini, Paolo F.; Arunachalam, Kavitha; De Luca, Valeria; Salahi, Sara; Boico, Alina; Klemetsen, Oystein; Birkelund, Yngve; Jacobsen, Svein K.; Bardati, Fernando; Tognolatti, Piero; Snow, Brent

    2012-01-01

    Background Vesicoureteral reflux (VUR) is a serious health problem leading to renal scarring in children. Current VUR detection involves traumatic x-ray imaging of kidneys following injection of contrast agent into bladder via invasive Foley catheter. We present an alternative non-invasive approach for detecting VUR by radiometric monitoring of kidney temperature while gently warming the bladder. Methods We report the design and testing of: i) 915MHz square slot antenna array for heating bladder, ii) EMI-shielded log spiral microstrip receive antenna, iii) high-sensitivity 1.375GHz total power radiometer, iv) power modulation approach to increase urine temperature relative to overlying perfused tissues, and v) invivo porcine experiments characterizing bladder heating and radiometric temperature of aaline filled 30mL balloon “kidney” implanted 3–4cm deep in thorax and varied 2–6°C from core temperature. Results SAR distributions are presented for two novel antennas designed to heat bladder and monitor deep kidney temperatures radiometrically. We demonstrate the ability to heat 180mL saline in in vivo porcine bladder to 40–44°C while maintaining overlying tissues <38°C using time-modulated square slot antennas coupled to the abdomen with room temperature water pad. Pathologic evaluations confirmed lack of acute thermal damage in pelvic tissues for up to three 20min bladder heat exposures. The radiometer clearly recorded 2–6°C changes of 30mL “kidney” targets at depth in 34°C invivo pig thorax. Conclusion A 915MHz antenna array can gently warm in vivo pig bladder without toxicity while a 1.375GHz radiometer with log spiral receive antenna detects ≥2°C rise in 30mL “urine” located 3–4cm deep in thorax, demonstrating more than sufficient sensitivity to detect Grade 4–5 reflux of warmed urine for non-invasive detection of VUR. PMID:22866211

  12. Non-invasive imaging and cellular tracking of pulmonary emboli by near-infrared fluorescence and positron-emission tomography.

    PubMed

    Page, Michael J; Lourenço, André L; David, Tovo; LeBeau, Aaron M; Cattaruzza, Fiore; Castro, Helena C; VanBrocklin, Henry F; Coughlin, Shaun R; Craik, Charles S

    2015-01-01

    Functional imaging of proteolytic activity is an emerging strategy to quantify disease and response to therapy at the molecular level. We present a new peptide-based imaging probe technology that advances these goals by exploiting enzymatic activity to deposit probes labelled with near-infrared (NIR) fluorophores or radioisotopes in cell membranes of disease-associated proteolysis. This strategy allows for non-invasive detection of protease activity in vivo and ex vivo by tracking deposited probes in tissues. We demonstrate non-invasive detection of thrombin generation in a murine model of pulmonary embolism using our protease-activated peptide probes in microscopic clots within the lungs with NIR fluorescence optical imaging and positron-emission tomography. Thrombin activity is imaged deep in tissue and tracked predominantly to platelets within the lumen of blood vessels. The modular design of our probes allows for facile investigation of other proteases, and their contributions to disease by tailoring the protease activation and cell-binding elements. PMID:26423607

  13. Non-invasive imaging and cellular tracking of pulmonary emboli by near-infrared fluorescence and positron-emission tomography

    PubMed Central

    Page, Michael J.; Lourenço, André L.; David, Tovo; LeBeau, Aaron M.; Cattaruzza, Fiore; Castro, Helena C.; VanBrocklin, Henry F.; Coughlin, Shaun R.; Craik, Charles S.

    2015-01-01

    Functional imaging of proteolytic activity is an emerging strategy to quantify disease and response to therapy at the molecular level. We present a new peptide-based imaging probe technology that advances these goals by exploiting enzymatic activity to deposit probes labelled with near-infrared (NIR) fluorophores or radioisotopes in cell membranes of disease-associated proteolysis. This strategy allows for non-invasive detection of protease activity in vivo and ex vivo by tracking deposited probes in tissues. We demonstrate non-invasive detection of thrombin generation in a murine model of pulmonary embolism using our protease-activated peptide probes in microscopic clots within the lungs with NIR fluorescence optical imaging and positron-emission tomography. Thrombin activity is imaged deep in tissue and tracked predominantly to platelets within the lumen of blood vessels. The modular design of our probes allows for facile investigation of other proteases, and their contributions to disease by tailoring the protease activation and cell-binding elements. PMID:26423607

  14. Non-invasive in vivo determination of the carotenoids beta-carotene and lycopene concentrations in the human skin using the Raman spectroscopic method

    NASA Astrophysics Data System (ADS)

    Darvin, M. E.; Gersonde, I.; Meinke, M.; Sterry, W.; Lademann, J.

    2005-08-01

    Resonance Raman spectroscopy was used as a fast and non-invasive optical method of measuring the absolute concentrations of beta-carotene and lycopene in living human skin. Beta-carotene and lycopene have different absorption values at 488 and 514.5 nm and, consequently, the Raman lines for beta-carotene and lycopene have different scattering efficiencies at 488 and 514.5 nm excitations. These differences were used for the determination of the concentrations of beta-carotene and lycopene. Using multiline Ar+ laser excitation, clearly distinguishable carotenoid Raman spectra can be obtained which are superimposed on a large fluorescence background. The Raman signals are characterized by two prominent Stokes lines at 1160 and 1525 cm-1, which have nearly identical relative intensities. Both substances were detected simultaneously. The Raman spectra are obtained rapidly, i.e. within about 10 s, and the required laser light exposure level is well within safety standards. The disturbance of the measurements by non-homogeneous skin pigmentation was avoided by using a relatively large measuring area of 35 mm2. It was shown that beta-carotene and lycopene distribution in human skin strongly depends upon the skin region studied and drastically changed inter-individually. Skin beta-carotene and lycopene concentrations are lower in smokers than in non-smokers and higher in the vegetarian group.

  15. Epidermal tattoo potentiometric sodium sensors with wireless signal transduction for continuous non-invasive sweat monitoring.

    PubMed

    Bandodkar, Amay J; Molinnus, Denise; Mirza, Omar; Guinovart, Tomás; Windmiller, Joshua R; Valdés-Ramírez, Gabriela; Andrade, Francisco J; Schöning, Michael J; Wang, Joseph

    2014-04-15

    This article describes the fabrication, characterization and application of an epidermal temporary-transfer tattoo-based potentiometric sensor, coupled with a miniaturized wearable wireless transceiver, for real-time monitoring of sodium in the human perspiration. Sodium excreted during perspiration is an excellent marker for electrolyte imbalance and provides valuable information regarding an individual's physical and mental wellbeing. The realization of the new skin-worn non-invasive tattoo-like sensing device has been realized by amalgamating several state-of-the-art thick film, laser printing, solid-state potentiometry, fluidics and wireless technologies. The resulting tattoo-based potentiometric sodium sensor displays a rapid near-Nernstian response with negligible carryover effects, and good resiliency against various mechanical deformations experienced by the human epidermis. On-body testing of the tattoo sensor coupled to a wireless transceiver during exercise activity demonstrated its ability to continuously monitor sweat sodium dynamics. The real-time sweat sodium concentration was transmitted wirelessly via a body-worn transceiver from the sodium tattoo sensor to a notebook while the subjects perspired on a stationary cycle. The favorable analytical performance along with the wearable nature of the wireless transceiver makes the new epidermal potentiometric sensing system attractive for continuous monitoring the sodium dynamics in human perspiration during diverse activities relevant to the healthcare, fitness, military, healthcare and skin-care domains. PMID:24333582

  16. Non-invasive Imaging of Idiopathic Pulmonary Fibrosis Using Cathepsin Protease Probes

    PubMed Central

    Withana, Nimali P.; Ma, Xiaowei; McGuire, Helen M.; Verdoes, Martijn; van der Linden, Wouter A.; Ofori, Leslie O.; Zhang, Ruiping; Li, Hao; Sanman, Laura E.; Wei, Ke; Yao, Shaobo; Wu, Peilin; Li, Fang; Huang, Hui; Xu, Zuojun; Wolters, Paul J.; Rosen, Glenn D.; Collard, Harold R.; Zhu, Zhaohui; Cheng, Zhen; Bogyo, Matthew

    2016-01-01

    Idiopathic pulmonary fibrosis (IPF) is a lethal, chronic, progressive disease characterized by formation of scar tissue within the lungs. Because it is a disease of unknown etiology, it is difficult to diagnose, to predict disease course and to devise treatment strategies. Recent evidence suggests that activated macrophages play key roles in the pathology of IPF. Therefore, imaging probes that specifically recognize these pools of activated immune cells could provide valuable information about how these cells contribute to the pathobiology of the disease. Here we demonstrate that cysteine cathepsin-targeted imaging probes can be used to monitor the contribution of macrophages to fibrotic disease progression in the bleomycin-induced murine model of pulmonary fibrosis. Furthermore, we show that the probes highlight regions of macrophage involvement in fibrosis in human biopsy tissues from IPF patients. Finally, we present first-in-human results demonstrating non-invasive imaging of active cathepsins in fibrotic lesions of patients with IPF. Together, our findings validate small molecule cysteine cathepsin probes for clinical PET imaging and suggest that they have the potential to be used to generate mechanistically-informative molecular information regarding cellular drivers of IPF disease severity and progression. PMID:26797565

  17. Non-invasive single-cell biomechanical analysis using live-imaging datasets.

    PubMed

    Pearson, Yanthe E; Lund, Amanda W; Lin, Alex W H; Ng, Chee P; Alsuwaidi, Aysha; Azzeh, Sara; Gater, Deborah L; Teo, Jeremy C M

    2016-09-01

    The physiological state of a cell is governed by a multitude of processes and can be described by a combination of mechanical, spatial and temporal properties. Quantifying cell dynamics at multiple scales is essential for comprehensive studies of cellular function, and remains a challenge for traditional end-point assays. We introduce an efficient, non-invasive computational tool that takes time-lapse images as input to automatically detect, segment and analyze unlabeled live cells; the program then outputs kinematic cellular shape and migration parameters, while simultaneously measuring cellular stiffness and viscosity. We demonstrate the capabilities of the program by testing it on human mesenchymal stem cells (huMSCs) induced to differentiate towards the osteoblastic (huOB) lineage, and T-lymphocyte cells (T cells) of naïve and stimulated phenotypes. The program detected relative cellular stiffness differences in huMSCs and huOBs that were comparable to those obtained with studies that utilize atomic force microscopy; it further distinguished naïve from stimulated T cells, based on characteristics necessary to invoke an immune response. In summary, we introduce an integrated tool to decipher spatiotemporal and intracellular dynamics of cells, providing a new and alternative approach for cell characterization. PMID:27422102

  18. Non-invasive prognostic protein biomarker signatures associated with colorectal cancer

    PubMed Central

    Surinova, Silvia; Radová, Lenka; Choi, Meena; Srovnal, Josef; Brenner, Hermann; Vitek, Olga; Hajdúch, Marián; Aebersold, Ruedi

    2015-01-01

    The current management of colorectal cancer (CRC) would greatly benefit from non-invasive prognostic biomarkers indicative of clinicopathological tumor characteristics. Here, we employed targeted proteomic profiling of 80 glycoprotein biomarker candidates across plasma samples of a well-annotated patient cohort with comprehensive CRC characteristics. Clinical data included 8-year overall survival, tumor staging, histological grading, regional localization, and molecular tumor characteristics. The acquired quantitative proteomic dataset was subjected to the development of biomarker signatures predicting prognostic clinical endpoints. Protein candidates were selected into the signatures based on significance testing and a stepwise protein selection, each within 10-fold cross-validation. A six-protein biomarker signature of patient outcome could predict survival beyond clinical stage and was able to stratify patients into groups of better and worse prognosis. We further evaluated the performance of the signature on the mRNA level and assessed its prognostic value in the context of previously published transcriptional signatures. Additional signatures predicting regional tumor localization and disease dissemination were also identified. The integration of rich clinical data, quantitative proteomic technologies, and tailored computational modeling facilitated the characterization of these signatures in patient circulation. These findings highlight the value of a simultaneous assessment of important prognostic disease characteristics within a single measurement. PMID:26253080

  19. Optical characterization of vocal folds by OCT-based laryngoscopy

    NASA Astrophysics Data System (ADS)

    Lueerssen, Kathrin; Wisweh, Henning; Ptok, Martin; Lubatschowski, Holger

    2007-02-01

    Optical coherence tomography (OCT) is a new non-invasive method to investigate biological tissue. It is particularly suitable for examination of human vocal folds due to its optical penetration depth of around 1.5mm. We developed a modified laryngoscope with an integrated OCT beam path for non-contact imaging of human vocal folds. In vivo studies on awake patients show that synchronous OCT and conventional laryngoscopy works well. For enabling the choice of the appropriate OCT encoding technique for OCT-based laryngoscopy measurements on simulated vibrations were performed with time domain (TD) and fourier domain (FD) OCT devices. The results show that TD-OCT is much more suitable for non-contact imaging than FD-OCT. In studies on porcine and monkey vocal folds the performance of femtosecond laser tissue ablation was analyzed with OCT monitoring. Histopathological sections could be well correlated with the OCT images. In future applications a combined system that uses one femtosecond laser as light source for tissue ablation as well as for OCT imaging is conceivable. In conclusion, OCT can be used as a pre-, intra- and post-operative diagnostic instrument for analysing the vocal fold structure down to the vocalis muscle allowing a more precise indication for potential subsequent invasive procedures. We suggest that OCT should be used in addition to established examination methods for diagnostic evaluation of vocal fold malignancies and functional alterations.

  20. Non-invasive molecular profiling of cancer using photoacoustic imaging of functionalized gold nanorods

    NASA Astrophysics Data System (ADS)

    Shah, Anant J.; Alles, Erwin J.; Box, Carol; Eccles, Suzanne A.; Robinson, Simon P.; deSouza, Nandita; Bamber, Jeffrey C.

    2014-03-01

    Although molecularly targeted cancer therapies have shown great promise, it is now evident that responses are dependent upon the molecular genetic context. Spatial and temporal tumour heterogeneity renders biopsy of solid tumours unsuitable for determining the genetic profile of the disease, making adaptation of appropriate therapy difficult. We have utilized the tunable optical absorption characteristic of gold nanorods to assess the potential of photoacoustics for non-invasive multiplexed molecular imaging. Gold nanorods with resonance peaks at 700nm and 900nm were functionalised with in-house antibodies ICR55 and ICR62, targeted to HER2 and EGFR transmembrane receptors, respectively. Three human squamous carcinoma cell lines (LICR-LON-HN4 expressing high HER2 and low EGFR, LICR-LON-HN3 expressing intermediate levels of HER2 and EGFR and A431 expressing high EGFR and low HER2) were incubated with the targeted nanorods for 24 hours. Cells were then incorporated as simulated tumours in tissue-like phantoms composed of 7.5% gelatin containing 0.5% Intralipid® for optical scattering and imaged at a depth of 2.5 cm, using a new clinical in-house multi-spectral photoacoustic imaging system. Images were obtained from the cell inclusions for wavelengths ranging from 710 to 950 nm at 40 nm intervals, and the mean amplitude of the photoacoustic image was computed for each wavelength, to determine their relative receptor expression levels. The molecular profile of the cells obtained using multi-wavelength photoacoustics had substantial similarity to that obtained using flow cytometry. These preliminary results confirm selective uptake of the functionalised nanorods, which reflects the cellular expression of therapeutically important oncoproteins, and give an indication of the potential of photoacoustics for multiplexed molecular profiling.

  1. Non-invasive VHF monitoring of low-temperature atmospheric pressure plasma

    NASA Astrophysics Data System (ADS)

    Law, V. J.; Daniels, S.; Walsh, J. L.; Kong, M. G.; Graham, L. M.; Gans, T.

    2010-06-01

    A real-time VHF swept frequency (20-300 MHz) reflectometry measurement for radio-frequency capacitive-coupled atmospheric pressure plasmas is described. The measurement is scalar, non-invasive and deployed on the main power line of the plasma chamber. The purpose of this VHF signal injection is to remotely interrogate in real-time the frequency reflection properties of plasma. The information obtained is used for remote monitoring of high-value atmospheric plasma processing. Measurements are performed under varying gas feed (helium mixed with 0-2% oxygen) and power conditions (0-40 W) on two contrasting reactors. The first is a classical parallel-plate chamber driven at 16 MHz with well-defined electrical grounding but limited optical access and the second is a cross-field plasma jet driven at 13.56 MHz with open optical access but with poor electrical shielding of the driven electrode. The electrical measurements are modelled using a lumped element electrical circuit to provide an estimate of power dissipated in the plasma as a function of gas and applied power. The performances of both reactors are evaluated against each other. The scalar measurements reveal that 0.1% oxygen admixture in helium plasma can be detected. The equivalent electrical model indicates that the current density between the parallel-plate reactor is of the order of 8-20 mA cm-2. This value is in accord with 0.03 A cm-2 values reported by Park et al (2001 J. Appl. Phys. 89 20-8). The current density of the cross-field plasma jet electrodes is found to be 20 times higher. When the cross-field plasma jet unshielded electrode area is factored into the current density estimation, the resultant current density agrees with the parallel-plate reactor. This indicates that the unshielded reactor radiates electromagnetic energy into free space and so acts as a plasma antenna.

  2. Monitoring molecular, functional and morphologic aspects of bone metastases using non-invasive imaging.

    PubMed

    Bauerle, Tobias; Komljenovic, Dorde; Semmler, Wolfhard

    2012-03-01

    Bone is among the most common locations of metastasis and therefore represents an important clinical target for diagnostic follow-up in cancer patients. In the pathogenesis of bone metastases, disseminated tumor cells proliferating in bone interact with the local microenvironment stimulating or inhibiting osteoclast and osteoblast activity. Non-invasive imaging methods monitor molecular, functional and morphologic changes in both compartments of these skeletal lesions - the bone and the soft tissue tumor compartment. In the bone compartment, morphologic information on skeletal destruction is assessed by computed tomography (CT) and radiography. Pathogenic processes of osteoclast and osteoblast activity, however, can be imaged using optical imaging, positron emission tomography (PET), single photon emission CT (SPECT) and skeletal scintigraphy. Accordingly, conventional magnetic resonance imaging (MRI) and CT as well as diffusion- weighted MRI and optical imaging are used to assess morphologic aspects on the macroscopic and cellular level of the soft tissue tumor compartment. Imaging methods such as PET, MR spectroscopy, dynamic contrast-enhanced techniques and vessel size imaging further elucidate on pathogenic processes in this compartment including information on metabolism and vascularization. By monitoring these aspects in bone lesions, new insights in the pathogenesis of skeletal metastases can be gained. In translation to the clinical situation, these novel methods for the monitoring of bone metastases might be applied in patients to improve follow-up of these lesions, in particular after therapeutic intervention. This review summarizes established and experimental imaging techniques for the monitoring of tumor and bone cell activity including molecular, functional and morphological aspects in bone metastases. PMID:22214500

  3. Optical Measurement Technique for Space Column Characterization

    NASA Technical Reports Server (NTRS)

    Barrows, Danny A.; Watson, Judith J.; Burner, Alpheus W.; Phelps, James E.

    2004-01-01

    A simple optical technique for the structural characterization of lightweight space columns is presented. The technique is useful for determining the coefficient of thermal expansion during cool down as well as the induced strain during tension and compression testing. The technique is based upon object-to-image plane scaling and does not require any photogrammetric calibrations or computations. Examples of the measurement of the coefficient of thermal expansion are presented for several lightweight space columns. Examples of strain measured during tension and compression testing are presented along with comparisons to results obtained with Linear Variable Differential Transformer (LVDT) position transducers.

  4. Characterization of Adaptive Optics at Keck Observatory

    SciTech Connect

    van Dam, M A; Macintosh, B A

    2003-07-24

    In this paper, the adaptive optics (AO) system at Keck Observatory is characterized. The AO system is described in detail. The physical parameters of the lenslets, CCD and deformable mirror, the calibration procedures and the signal processing algorithms are explained. Results of sky performance tests are presented: the AO system is shown to deliver images with an average Strehl ratio of up to 0.37 at 1.59 {micro}m using a bright guide star. An error budget that is consistent with the observed image quality is presented.

  5. Continuing education course #1: non-invasive imaging as a problem-solving tool and translational biomarker strategy in toxicologic pathology.

    PubMed

    Peterson, Richard A; Gabrielson, Kathy L; Allan Johnson, G; Pomper, Martin G; Coatney, Robert W; Winkelmann, Christopher T

    2011-01-01

    The continuing education course "Non-Invasive Imaging as a Problem-Solving Tool and Translational Biomarker Strategy in Toxicologic Pathology" provided a thorough overview of commonly used imaging modalities and the logistics required for integration of small animal imaging into toxicologic pathology. Non-invasive imaging (NIN) is gaining acceptance as an important modality in toxicologic pathology. This technology allows nonterminal, time-course evaluation of functional and morphologic endpoints and can be used to translate biomarkers between preclinical animal models and human patients. NIN can support drug development as well as basic research in academic or industrial environments. An initial overview of theoretical principles was followed by focused presentations on magnetic resonance imaging (MRI)/magnetic resonance microscopy (MRM), positron emission tomography (PET)/single proton emission computed tomography (SPECT), ultrasonography (US, primarily focused on echocardiography), optical (bioluminescent) imaging, and computed tomography (CT). The choice of imaging modality will depend on the research question and the needed resolution. PMID:21147931

  6. Optical Material Characterization Using Microdisk Cavities

    NASA Astrophysics Data System (ADS)

    Michael, Christopher P.

    Since Jack Kilby recorded his "Monolithic Idea" for integrated circuits in 1958, microelectronics companies have invested billions of dollars in developing the silicon material system to increase performance and reduce cost. For decades, the industry has made Moore's Law, concerning cost and transistor density, a self-fulfilling prophecy by integrating technical and material requirements vertically down their supply chains and horizontally across competitors in the market. At recent technology nodes, the unacceptable scaling behavior of copper interconnects has become a major design constraint by increasing latency and power consumption---more than 50% of the power consumed by high speed processors is dissipated by intrachip communications. Optical networks at the chip scale are a potential low-power high-bandwidth replacement for conventional global interconnects, but the lack of efficient on-chip optical sources has remained an outstanding problem despite significant advances in silicon optoelectronics. Many material systems are being researched, but there is no ideal candidate even though the established infrastructure strongly favors a CMOS-compatible solution. This thesis focuses on assessing the optical properties of materials using microdisk cavities with the intention to advance processing techniques and materials relevant to silicon photonics. Low-loss microdisk resonators are chosen because of their simplicity and long optical path lengths. A localized photonic probe is developed and characterized that employs a tapered optical-fiber waveguide, and it is utilized in practical demonstrations to test tightly arranged devices and to help prototype new fabrication methods. A case study in AlxGa1-xAs illustrates how the optical scattering and absorption losses can be obtained from the cavity-waveguide transmission. Finally, single-crystal Er2O3 epitaxially grown on silicon is analyzed in detail as a potential CMOS-compatable gain medium due to its high Er3

  7. Use of Entero-Test, a simple approach for non-invasive clinical evaluation of the biliary disposition of drugs

    PubMed Central

    Guiney, William J; Beaumont, Claire; Thomas, Steve R; Robertson, Darren C; McHugh, Simon M; Koch, Annelize; Richards, Duncan

    2011-01-01

    AIM To evaluate the non-invasive collection of bile from healthy human subjects for the qualitative characterization of the biliary disposition of a drug, using spectrometric techniques. METHODS Twenty subjects underwent non-invasive bile capture using a peroral string test (Entero-Test) device prior to and following a single oral dose of simvastatin (80 mg). The device, consisting of a weighted gelatin capsule containing a highly absorbent nylon string, was swallowed by each subject with the proximal end of the string taped to the face. Once the weighted string was judged to have reached the duodenum, gallbladder contraction was stimulated in order to release bile. The string was then retrieved via the mouth, and bile samples were analysed for drug-related material using spectrometric and spectroscopic techniques following solvent extraction. RESULTS Numerous metabolites of simvastatin were detected, and the major metabolites were consistent with those reported from studies where bile was collected using invasive techniques from patients dosed with [14C]-simvastatin. CONCLUSIONS The results from this study demonstrate the utility of deploying the Entero-Test in human studies to provide structural information on biliary metabolites. This can be readily applied in drug development studies, including those in the target patient population and may eliminate the need for more invasive sampling techniques. PMID:21366667

  8. Online monitoring of fermentation processes via non-invasive low-field NMR.

    PubMed

    Kreyenschulte, Dirk; Paciok, Eva; Regestein, Lars; Blümich, Bernhard; Büchs, Jochen

    2015-09-01

    For the development of biotechnological processes in academia as well as in industry new techniques are required which enable online monitoring for process characterization and control. Nuclear magnetic resonance (NMR) spectroscopy is a promising analytical tool, which has already found broad applications in offline process analysis. The use of online monitoring, however, is oftentimes constrained by high complexity of custom-made NMR bioreactors and considerable costs for high-field NMR instruments (>US$200,000). Therefore, low-field (1) H NMR was investigated in this study in a bypass system for real-time observation of fermentation processes. The new technique was validated with two microbial systems. For the yeast Hansenula polymorpha glycerol consumption could accurately be assessed in spite of the presence of high amounts of complex constituents in the medium. During cultivation of the fungal strain Ustilago maydis, which is accompanied by the formation of several by-products, the concentrations of glucose, itaconic acid, and the relative amount of glycolipids could be quantified. While low-field spectra are characterized by reduced spectral resolution compared to high-field NMR, the compact design combined with the high temporal resolution (15 s-8 min) of spectra acquisition allowed online monitoring of the respective processes. Both applications clearly demonstrate that the investigated technique is well suited for reaction monitoring in opaque media while at the same time it is highly robust and chemically specific. It can thus be concluded that low-field NMR spectroscopy has a great potential for non-invasive online monitoring of biotechnological processes at the research and practical industrial scales. PMID:25850822

  9. Rugometric and microtopographic non-invasive inspection in dental-resin composites and zirconia ceramics

    NASA Astrophysics Data System (ADS)

    Fernández-Oliveras, Alicia; Costa, Manuel F. M.; Pecho, Oscar E.; Rubiño, Manuel; Pérez, María. M.

    2013-11-01

    Surface properties are essential for a complete characterization of biomaterials. In restorative dentistry, the study of the surface properties of materials meant to replace dental tissues in an irreversibly diseased tooth is important to avoid harmful changes in future treatments. We have experimentally analyzed the surface characterization parameters of two different types of dental-resin composites and pre-sintered and sintered zirconia ceramics. We studied two shades of both composite types and two sintered zirconia ceramics: colored and uncolored. Moreover, a surface treatment was applied to one specimen of each dental-resin. All the samples were submitted to rugometric and microtopographic non-invasive inspection with the MICROTOP.06.MFC laser microtopographer in order to gather meaningful statistical parameters such as the average roughness (Ra), the root-mean-square deviation (Rq), the skewness (Rsk), and the kurtosis of the surface height distribution (Rku). For a comparison of the different biomaterials, the uncertainties associated to the surface parameters were also determined. With respect to Ra and Rq, significant differences between the composite shades were found. Among the dental resins, the nanocomposite presented the highest values and, for the zirconia ceramics, the pre-sintered sample registered the lowest ones. The composite performance may have been due to cluster-formation variations. Except for the composites with the surface treatment, the sample surfaces had approximately a normal distribution of heights. The surface treatment applied to the composites increased the average roughness and moved the height distribution farther away from the normal distribution. The zirconia-sintering process resulted in higher average roughness without affecting the height distribution.

  10. Tissue-Informative Mechanism for Wearable Non-invasive Continuous Blood Pressure Monitoring

    NASA Astrophysics Data System (ADS)

    Woo, Sung Hun; Choi, Yun Young; Kim, Dae Jung; Bien, Franklin; Kim, Jae Joon

    2014-10-01

    Accurate continuous direct measurement of the blood pressure is currently available thru direct invasive methods via intravascular needles, and is mostly limited to use during surgical procedures or in the intensive care unit (ICU). Non-invasive methods that are mostly based on auscultation or cuff oscillometric principles do provide relatively accurate measurement of blood pressure. However, they mostly involve physical inconveniences such as pressure or stress on the human body. Here, we introduce a new non-invasive mechanism of tissue-informative measurement, where an experimental phenomenon called subcutaneous tissue pressure equilibrium is revealed and related for application in detection of absolute blood pressure. A prototype was experimentally verified to provide an absolute blood pressure measurement by wearing a watch-type measurement module that does not cause any discomfort. This work is supposed to contribute remarkably to the advancement of continuous non-invasive mobile devices for 24-7 daily-life ambulatory blood-pressure monitoring.

  11. Tissue-informative mechanism for wearable non-invasive continuous blood pressure monitoring.

    PubMed

    Woo, Sung Hun; Choi, Yun Young; Kim, Dae Jung; Bien, Franklin; Kim, Jae Joon

    2014-01-01

    Accurate continuous direct measurement of the blood pressure is currently available thru direct invasive methods via intravascular needles, and is mostly limited to use during surgical procedures or in the intensive care unit (ICU). Non-invasive methods that are mostly based on auscultation or cuff oscillometric principles do provide relatively accurate measurement of blood pressure. However, they mostly involve physical inconveniences such as pressure or stress on the human body. Here, we introduce a new non-invasive mechanism of tissue-informative measurement, where an experimental phenomenon called subcutaneous tissue pressure equilibrium is revealed and related for application in detection of absolute blood pressure. A prototype was experimentally verified to provide an absolute blood pressure measurement by wearing a watch-type measurement module that does not cause any discomfort. This work is supposed to contribute remarkably to the advancement of continuous non-invasive mobile devices for 24-7 daily-life ambulatory blood-pressure monitoring. PMID:25331013

  12. [Non-invasive mechanical ventilation in the pre- and intraoperative period and difficult airway].

    PubMed

    Esquinas, A M; Jover, J L; Úbeda, A; Belda, F J

    2015-11-01

    Non-invasive mechanical ventilation is a method of ventilatory assistance aimed at increasing alveolar ventilation, thus achieving, in selected subjects, the avoidance of endotracheal intubation and invasive mechanical ventilation, with the consequent improvement in survival. There has been a systematic review and study of the technical, clinical experiences, and recommendations concerning the application of non-invasive mechanical ventilation in the pre- and intraoperative period. The use of prophylactic non-invasive mechanical ventilation before surgery that involves significant alterations in the ventilatory function may decrease the incidence of postoperative respiratory complications. Its intraoperative use will mainly depend on the type of surgery, type of anaesthetic technique, and the clinical status of the patient. Its use allows greater anaesthetic depth without deterioration of oxygenation and ventilation of patients. PMID:25702198

  13. Non-invasive Central and Peripheral Stimulation: New Hope for Essential Tremor?

    PubMed Central

    Chalah, Moussa A.; Lefaucheur, Jean-Pascal; Ayache, Samar S.

    2015-01-01

    Essential tremor (ET) is among the most frequent movement disorders. It usually manifests as a postural and kinematic tremor of the arms, but may also involve the head, voice, lower limbs, and trunk. An oscillatory network has been proposed as a neural correlate of ET, and is mainly composed of the olivocerebellar system, thalamus, and motor cortex. Since pharmacological agents have limited benefits, surgical interventions like deep brain stimulation are the last-line treatment options for the most severe cases. Non-invasive brain stimulation techniques, particularly transcranial magnetic or direct current stimulation, are used to ameliorate ET. Their non-invasiveness, along with their side effects profile, makes them an appealing treatment option. In addition, peripheral stimulation has been applied in the same perspective. Hence, the aim of the present review is to shed light on the emergent use of non-invasive central and peripheral stimulation techniques in this interesting context. PMID:26635516

  14. Apparatus and method for characterizing ultrafast polarization varying optical pulses

    DOEpatents

    Smirl, A.; Trebino, R.P.

    1999-08-10

    Practical techniques are described for characterizing ultrafast potentially ultraweak, ultrashort optical pulses. The techniques are particularly suited to the measurement of signals from nonlinear optical materials characterization experiments, whose signals are generally too weak for full characterization using conventional techniques. 2 figs.

  15. Spectroscopic imaging of blood vessels only near the skin surface for non-invasive blood glucose measurement

    NASA Astrophysics Data System (ADS)

    Fujiwara, Masaru; Sato, Shun; Abeygunawardhana, Pradeep K. W.; Suzuki, Satoru; Nishiyama, Akira; Wada, Kenji; Ishimaru, Ichiro

    2015-07-01

    To realize the non-invasive blood glucose measurement, it will be effective to acquire the spectroscopic imaging of blood vessels only near the skin surface for eliminating other biological-component's disturbances. Our proposed imaging-type 2-dimensional Fourier spectroscopic imaging can limit the measuring depth into focal plane with high light detection sensitivity. Thus, the proposed method will be suitable for measuring only near the skin surface with detecting weak reflected light from inner biomembrane. But reflectance of skin surface is more than 1000 times larger than inner skin's reflectance. Paying attention on Fresnel reflection, fingers what were illuminated by p-polarized beam from Brewster's angle were observed with crossed-Nicol dark field optics. We successfully acquired spectroscopic characteristics of hemoglobin at vein area near the skin surface.

  16. Comparison of non-invasive and invasive blood pressure in aeromedical care.

    PubMed

    McMahon, N; Hogg, L A; Corfield, A R; Exton, A D

    2012-12-01

    Blood pressure measurement is an essential physiological measurement for all critically ill patients. Previous work has shown that non-invasive blood pressure is not an accurate reflection of invasive blood pressure measurement. In a transport environment, the effects of motion and vibration may make non-invasive blood pressure less accurate. Consecutive critically ill patients transported by a dedicated aeromedical retrieval and critical care transfer service with simultaneous invasive and non-invasive blood pressure measurements were analysed. Two sets of measurements were recorded, first in a hospital environment before departure (pre-flight) and a second during aeromedical transport (in-flight). A total of 56 complete sets of data were analysed. Bland-Altman plots showed limits of agreement (precision) for pre-flight systolic blood pressure were -37.3 mmHg to 30.0 mmHg, and for pre-flight mean arterial pressure -20.5 mmHg to 25.0 mmHg. The limits of agreement for in-flight systolic blood pressure were -40.6 mmHg to 33.1 mmHg, while those for in-flight mean blood pressure in-flight were -23.6 mmHg to 24.6 mmHg. The bias for the four conditions ranged from 0.5 to -3.8 mmHg. There were no significant differences in values between pre-flight and in-flight blood pressure measurements for all categories of blood pressure measurement. Thus, our data show that non-invasive blood pressure is not a precise reflection of invasive intra-arterial blood pressure. Mean blood pressure measured non-invasively may be a better marker of invasive blood pressure than systolic blood pressure. Our data show no evidence of non-invasive blood pressures being less accurate in an aeromedical transport environment. PMID:23033983

  17. Non-invasive reproductive and stress endocrinology in amphibian conservation physiology

    PubMed Central

    Narayan, E. J.

    2013-01-01

    Non-invasive endocrinology utilizes non-invasive biological samples (such as faeces, urine, hair, aquatic media, and saliva) for the quantification of hormones in wildlife. Urinary-based enzyme immunoassay (EIA) and radio-immunoassay have enabled the rapid quantification of reproductive and stress hormones in amphibians (Anura: Amphibia). With minimal disturbance, these methods can be used to assess the ovarian and testicular endocrine functions as well as physiological stress in captive and free-living populations. Non-invasive endocrine monitoring has therefore greatly advanced our knowledge of the functioning of the stress endocrine system (the hypothalamo–pituitary–interrenal axis) and the reproductive endocrine system (the hypothalamo–pituitary–gonadal axis) in the amphibian physiological stress response, reproductive ecology, health and welfare, and survival. Biological (physiological) validation is necessary for obtaining the excretory lag time of hormone metabolites. Urinary-based EIA for the major reproductive hormones, estradiol and progesterone in females and testosterone in males, can be used to track the reproductive hormone profiles in relationship to reproductive behaviour and environmental data in free-living anurans. Urinary-based corticosterone metabolite EIA can be used to assess the sublethal impacts of biological stressors (such as invasive species and pathogenic diseases) as well as anthropogenic induced environmental stressors (e.g. extreme temperatures) on free-living populations. Non-invasive endocrine methods can also assist in the diagnosis of success or failure of captive breeding programmes by measuring the longitudinal patterns of changes in reproductive hormones and corticosterone within captive anurans and comparing the endocrine profiles with health records and reproductive behaviour. This review paper focuses on the reproductive and the stress endocrinology of anurans and demonstrates the uses of non-invasive endocrinology

  18. Non-invasive reproductive and stress endocrinology in amphibian conservation physiology.

    PubMed

    Narayan, E J

    2013-01-01

    Non-invasive endocrinology utilizes non-invasive biological samples (such as faeces, urine, hair, aquatic media, and saliva) for the quantification of hormones in wildlife. Urinary-based enzyme immunoassay (EIA) and radio-immunoassay have enabled the rapid quantification of reproductive and stress hormones in amphibians (Anura: Amphibia). With minimal disturbance, these methods can be used to assess the ovarian and testicular endocrine functions as well as physiological stress in captive and free-living populations. Non-invasive endocrine monitoring has therefore greatly advanced our knowledge of the functioning of the stress endocrine system (the hypothalamo-pituitary-interrenal axis) and the reproductive endocrine system (the hypothalamo-pituitary-gonadal axis) in the amphibian physiological stress response, reproductive ecology, health and welfare, and survival. Biological (physiological) validation is necessary for obtaining the excretory lag time of hormone metabolites. Urinary-based EIA for the major reproductive hormones, estradiol and progesterone in females and testosterone in males, can be used to track the reproductive hormone profiles in relationship to reproductive behaviour and environmental data in free-living anurans. Urinary-based corticosterone metabolite EIA can be used to assess the sublethal impacts of biological stressors (such as invasive species and pathogenic diseases) as well as anthropogenic induced environmental stressors (e.g. extreme temperatures) on free-living populations. Non-invasive endocrine methods can also assist in the diagnosis of success or failure of captive breeding programmes by measuring the longitudinal patterns of changes in reproductive hormones and corticosterone within captive anurans and comparing the endocrine profiles with health records and reproductive behaviour. This review paper focuses on the reproductive and the stress endocrinology of anurans and demonstrates the uses of non-invasive endocrinology for

  19. Non-invasive Ventilation in Premature Infants: Based on Evidence or Habit

    PubMed Central

    Garg, Shalabh; Sinha, Sunil

    2013-01-01

    Despite surfactant and mechanical ventilation being the standard of care for preterm infants with respiratory failure, non-invasive respiratory support is increasingly being employed in neonatal units. The latter can be accomplished in a variety of ways but none of them have been proven so far to be superior to intubation and mechanical ventilation. Nonetheless, they appear to be safe and effective in experienced hands. This article relates to the use of non-invasive forms of respiratory support and evidence is reviewed from the clinical trials which have evaluated the use of these techniques. PMID:24404523

  20. Personalized management of cirrhosis by non-invasive tests of liver fibrosis.

    PubMed

    Wong, Grace Lai-Hung; Espinosa, Wendell Zaragoza; Wong, Vicnent Wai-Sun

    2015-09-01

    Owing to the high prevalence of various chronic liver diseases, cirrhosis is one of the leading causes of morbidity and mortality worldwide. In recent years, the development of non-invasive tests of fibrosis allows accurate diagnosis of cirrhosis and reduces the need for liver biopsy. In this review, we discuss the application of these non-invasive tests beyond the diagnosis of cirrhosis. In particular, their role in the selection of patients for hepatocellular carcinoma surveillance and varices screening is highlighted. PMID:26523265

  1. Innovative non-invasive analysis techniques for cultural heritage using terahertz technology

    NASA Astrophysics Data System (ADS)

    Fukunaga, Kaori; Hosako, I.

    2010-08-01

    Terahertz (THz) spectroscopy and THz imaging techniques are expected to have great potential for carrying out the non-invasive analysis of artworks. THz waves can penetrate opaque materials and they can perform three-dimensional material mapping non-destructively by spectroscopic imaging. Several attempts have been made to analyse artworks. Clear results, such as imaging of hidden art by using model paintings, have been obtained by many institutions. We succeeded to observe the first ever non-invasive cross-sectional image of a tempera masterpiece by Giotto. These results prove that THz technology can yield useful information in art conservation science.

  2. New Imaging Methods for Non-invasive Assessment of Mechanical, Structural, and Biochemical Properties of Human Achilles Tendon: A Mini Review

    PubMed Central

    Fouré, Alexandre

    2016-01-01

    The mechanical properties of tendon play a fundamental role to passively transmit forces from muscle to bone, withstand sudden stretches, and act as a mechanical buffer allowing the muscle to work more efficiently. The use of non-invasive imaging methods for the assessment of human tendon's mechanical, structural, and biochemical properties in vivo is relatively young in sports medicine, clinical practice, and basic science. Non-invasive assessment of the tendon properties may enhance the diagnosis of tendon injury and the characterization of recovery treatments. While ultrasonographic imaging is the most popular tool to assess the tendon's structural and indirectly, mechanical properties, ultrasonographic elastography, and ultra-high field magnetic resonance imaging (UHF MRI) have recently emerged as potentially powerful techniques to explore tendon tissues. This paper highlights some methodological cautions associated with conventional ultrasonography and perspectives for in vivo human Achilles tendon assessment using ultrasonographic elastography and UHF MRI. PMID:27512376

  3. Smart Optical Material Characterization System and Method

    NASA Technical Reports Server (NTRS)

    Choi, Sang Hyouk (Inventor); Park, Yeonjoon (Inventor)

    2015-01-01

    Disclosed is a system and method for characterizing optical materials, using steps and equipment for generating a coherent laser light, filtering the light to remove high order spatial components, collecting the filtered light and forming a parallel light beam, splitting the parallel beam into a first direction and a second direction wherein the parallel beam travelling in the second direction travels toward the material sample so that the parallel beam passes through the sample, applying various physical quantities to the sample, reflecting the beam travelling in the first direction to produce a first reflected beam, reflecting the beam that passes through the sample to produce a second reflected beam that travels back through the sample, combining the second reflected beam after it travels back though the sample with the first reflected beam, sensing the light beam produced by combining the first and second reflected beams, and processing the sensed beam to determine sample characteristics and properties.

  4. Parabolic Trough VSHOT Optical Characterization in 2005-2006 (Presentation)

    SciTech Connect

    Wendelin, T.

    2006-02-01

    This presentation regarding parabolic trough VSHOT optical characterization describes trough deployment and operation phases including: development, manufacture/installation, and maintenance/operation.

  5. Optical characterization of lyotropic chromonic liquid crystals

    NASA Astrophysics Data System (ADS)

    Liu, Hui

    Lyotropic chromonic liquid crystals (LCLCs) represent a special class of lyotropic mesophases markedly different from conventional amphiphilic mesogens. Materials forming LCLCs are composed of plank-like molecules with a polyaromatic central core and hydrophilic ionic groups at the periphery. The individual molecules tend to assemble into rodlike aggregates that form the N phase once the concentration exceeds about 0.1M. The LCLC materials show a tremendous potential for applications in optics as self-assembling polarizing and compensating films and in the area of real-time biological sensing. The emerging applications require an understanding of basic properties of LCLC. This work addresses these needs by providing the optical characterization of LCLC. We studied in detail the optical anisotropic properties of three different nematic LCLCs: disodium cromoglycate (DSCG), Blue 27, and Violet 20. We determined the birefringence of these three materials as the function of the temperature T and wavelength lambda and the corresponding dependencies of the absorption coefficients for Blue 27 and Violet 20. The birefringence is negative and significantly lower in the absolute value as compared to the birefringence of typical thermotropic N materials. We determined the scalar order parameter of the nematic phase of Blue 27 and its temperature dependence. The scalar order parameter is close to the one predicted by the classic Onsager theory for solutions of rigid rods. However, this similarity is not complete, as the measured scalar order parameter depends on temperature. The I-N pretransitional fluctuations in an aqueous solution of DSCG were studied by light scattering. We obtained the correlation length of the orientational order-parameter fluctuations of isotropic DSCG solution. The pretransitional behavior of light scattering does not completely follow the classic Landau-de Gennes model. This feature is explained by the variable length of DSCG aggregates as a function

  6. Characterization of fluoride nanocrystals for optical refrigeration

    NASA Astrophysics Data System (ADS)

    Soares de Lima Filho, Elton; Quintanilla, Marta; Vetrone, Fiorenzo; Nemova, Galina; Kummara, Venkata Krishaniah; Kashyap, Raman

    2015-03-01

    This paper reports on the characterization of nanocrystalline powders of ytterbium doped YLiF4 for applications in optical refrigeration. Here we used powders with nanocrystals of Yb 3+ concentrations of (10, 15, 20) mol % and lengths (70, 66, 96) nm. Our preliminary spectroscopic measurements did not show an enhancement in the absorption at the long-wavelength tail of the spectra of the nanocrystalline powder when compared with bulk Yb:YLiF4, indicating that the increase of the phonon-assisted excitation is not large enough to play a significant role in cooling in the present conditions. One advantage of nanocrystalline powders over bulk crystals is the possibility of enhancing the absorption by the realization of cavity-less pump recycling through photon localization [1]. While photon localization also increases the reabsorption of the fluorescence depending on the quantum efficiency of the material and can mitigate cooling, it allows the use of crystals of low enough concentrations to avoid deleterious effects such as ion-ion energy transfer followed by quenching. The pump intensity enhancement favors upconversion luminescence to visible wavelengths, which can be used for optical refrigeration and extends the scope of the application for the material. We observed both green and blue emission from the samples and investigate the processes which lead to it. We present the experimental investigation of the nanocrystals' absorption and emission spectra and the first excited state lifetime measurements, which are used to estimate the nanocrystal's photoluminescence quantum efficiency.

  7. Non-Invasive UWB Sensing of Astronauts' Breathing Activity

    PubMed Central

    Baldi, Marco; Cerri, Graziano; Chiaraluce, Franco; Eusebi, Lorenzo; Russo, Paola

    2015-01-01

    The use of a UWB system for sensing breathing activity of astronauts must account for many critical issues specific to the space environment. The aim of this paper is twofold. The first concerns the definition of design constraints about the pulse amplitude and waveform to transmit, as well as the immunity requirements of the receiver. The second issue concerns the assessment of the procedures and the characteristics of the algorithms to use for signal processing to retrieve the breathing frequency and respiration waveform. The algorithm has to work correctly in the presence of surrounding electromagnetic noise due to other sources in the environment. The highly reflecting walls increase the difficulty of the problem and the hostile scenario has to be accurately characterized. Examples of signal processing techniques able to recover breathing frequency in significant and realistic situations are shown and discussed. PMID:25558995

  8. Non-invasive analysis of acquired resistance to cancer therapy by sequencing of plasma DNA.

    PubMed

    Murtaza, Muhammed; Dawson, Sarah-Jane; Tsui, Dana W Y; Gale, Davina; Forshew, Tim; Piskorz, Anna M; Parkinson, Christine; Chin, Suet-Feung; Kingsbury, Zoya; Wong, Alvin S C; Marass, Francesco; Humphray, Sean; Hadfield, James; Bentley, David; Chin, Tan Min; Brenton, James D; Caldas, Carlos; Rosenfeld, Nitzan

    2013-05-01

    Cancers acquire resistance to systemic treatment as a result of clonal evolution and selection. Repeat biopsies to study genomic evolution as a result of therapy are difficult, invasive and may be confounded by intra-tumour heterogeneity. Recent studies have shown that genomic alterations in solid cancers can be characterized by massively parallel sequencing of circulating cell-free tumour DNA released from cancer cells into plasma, representing a non-invasive liquid biopsy. Here we report sequencing of cancer exomes in serial plasma samples to track genomic evolution of metastatic cancers in response to therapy. Six patients with advanced breast, ovarian and lung cancers were followed over 1-2 years. For each case, exome sequencing was performed on 2-5 plasma samples (19 in total) spanning multiple courses of treatment, at selected time points when the allele fraction of tumour mutations in plasma was high, allowing improved sensitivity. For two cases, synchronous biopsies were also analysed, confirming genome-wide representation of the tumour genome in plasma. Quantification of allele fractions in plasma identified increased representation of mutant alleles in association with emergence of therapy resistance. These included an activating mutation in PIK3CA (phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha) following treatment with paclitaxel; a truncating mutation in RB1 (retinoblastoma 1) following treatment with cisplatin; a truncating mutation in MED1 (mediator complex subunit 1) following treatment with tamoxifen and trastuzumab, and following subsequent treatment with lapatinib, a splicing mutation in GAS6 (growth arrest-specific 6) in the same patient; and a resistance-conferring mutation in EGFR (epidermal growth factor receptor; T790M) following treatment with gefitinib. These results establish proof of principle that exome-wide analysis of circulating tumour DNA could complement current invasive biopsy approaches to identify

  9. A New Method for Non-Invasive Estimation of Human Muscle Fiber Type Composition

    PubMed Central

    Baguet, Audrey; Everaert, Inge; Hespel, Peter; Petrovic, Mirko; Achten, Eric; Derave, Wim

    2011-01-01

    Background It has been established that excellence in sports with short and long exercise duration requires a high proportion of fast-twitch (FT) or type-II fibers and slow-twitch (ST) or type-I fibers, respectively. Until today, the muscle biopsy method is still accepted as gold standard to measure muscle fiber type composition. Because of its invasive nature and high sampling variance, it would be useful to develop a non-invasive alternative. Methodology Eighty-three control subjects, 15 talented young track-and-field athletes, 51 elite athletes and 14 ex-athletes volunteered to participate in the current study. The carnosine content of all 163 subjects was measured in the gastrocnemius muscle by proton magnetic resonance spectroscopy (1H-MRS). Muscle biopsies for fiber typing were taken from 12 untrained males. Principal Findings A significant positive correlation was found between muscle carnosine, measured by 1H-MRS, and percentage area occupied by type II fibers. Explosive athletes had ∼30% higher carnosine levels compared to a reference population, whereas it was ∼20% lower than normal in typical endurance athletes. Similar results were found in young talents and ex-athletes. When active elite runners were ranked according to their best running distance, a negative sigmoidal curve was found between logarithm of running distance and muscle carnosine. Conclusions Muscle carnosine content shows a good reflection of the disciplines of elite track-and-field athletes and is able to distinguish between individual track running distances. The differences between endurance and sprint muscle types is also observed in young talents and former athletes, suggesting this characteristic is genetically determined and can be applied in early talent identification. This quick method provides a valid alternative for the muscle biopsy method. In addition, this technique may also contribute to the diagnosis and monitoring of many conditions and diseases that are

  10. Evaluation of an Improved Non-invasive Fetal Sex Determination in Haemophilia A Patients

    PubMed Central

    Mokari-Zadeh, Narmin

    2015-01-01

    Background Haemophilia A (HA) is the most severe sex-linked bleeding disorder that is characterized with non-controlled and often threatening Haemorrhage. Routine fetal sex determination in early pregnancy with Haemophilia is based on invasive procedures that can be dangerous to the mother and fetus. Aim The goal of this study is to present an improved assay for the non-invasive fetal sex determination using a Real-Time duplex PCR on the free fetal DNA (ffDNA) obtained from the maternal serum of the HA carriers. Materials and Methods Blood samples were eventually collected from 23 pregnant HA carriers between the 8th and 12th weeks of gestation, and after amplification by duplex-PCR of the single copy of Y chromosome-specific sequence (SRY), the product was then subjected to Real-Time PCR analysis. Results Data were compared with the outcome of chorionic villus sampling (CVS) and indicated that the SRY sequence was detected in 6 of 6 serum samples from male pregnancies and that sequence was absent in 9 samples where the fetus was female. The remaining samples determined without having the CVS positive samples. Conclusion We tried to develop a Real-Time duplex PCR for accurate diagnosis of fetal gender early in the pregnancy of HA carriers. This study has brought up two remarkable points, the first is the method’s improvement with high specificity in sex determination, especially in screening of prenatal sex-linked disorders in male gender and the second is that fresh serum samples would be a good source for this purpose, advocated by similar studies carried out in this regard. PMID:26393142

  11. Non-invasive laser Raman detection of lycopene and ž-carotene antioxidants in skin

    NASA Astrophysics Data System (ADS)

    Ermakov, Igor V.; Ermakova, Maia R.; Gellermann, Werner

    2003-07-01

    The predominant long-chain carotenoids found in the human skin are lycopene and β-carotene. They are powerful antioxidants and thought to act as scavengers for free radicals and single oxygen that are formed by excessive exposure of skin to sunlight. However the role of the particular representatives of the carotenoid antioxidants family in the skin defense mechanism is still unclear and has to be clarified. We demonstrate the opportunity for fast non-invasive selective quantitative detection of β-carotene and lycopene in human skin employing Raman spectroscopy. Analyzing Raman signals originating from the carbon-carbon double bond stretch vibrations of the molecules under blue and green laser excitation we were able to characterize quantitativly the concentrations of each carotenoid in alive human skin. In this method we take an advantage of different Raman cross-section spectral profile for β-carotene and lycopene molecules. This novel technique allows the quantitative assessment of individual carotenoid species in the skin rather then the cumulative level of long-chain carotenoids mixture as we could measure in our previous works. The required laser light exposure levels are well within safety standards. Prelimininary dichoromatic Raman measurements reveal significant differences in the carotenoid composition of different volunteer's skin: even in statistically small group of seven subjects the ratio of β-carotene-to-lycopene in their skin vary from 0.5 to 1.6. This technique holds promise as a method of rapid screening of carotenoids composition of human skin in large populations and suitable in clinical studies for assessing the risk for cutaneous diseases.

  12. Non-invasive pneumococcal pneumonia in Portugal--serotype distribution and antimicrobial resistance.

    PubMed

    Horácio, Andreia N; Lopes, Joana P; Ramirez, Mário; Melo-Cristino, José

    2014-01-01

    There is limited information on the serotypes causing non-invasive pneumococcal pneumonia (NIPP). Our aim was to characterize pneumococci causing NIPP in adults to determine recent changes in serotype prevalence, the potential coverage of pneumococcal vaccines and changes in antimicrobial resistance. Serotypes and antimicrobial susceptibility profiles of a sample of 1300 isolates recovered from adult patients (≥18 yrs) between 1999 and 2011 (13 years) were determined. Serotype 3 was the most frequent cause of NIPP accounting for 18% of the isolates. The other most common serotypes were 11A (7%), 19F (7%), 19A (5%), 14 (4%), 22F (4%), 23F (4%) and 9N (4%). Between 1999 and 2011, there were significant changes in the proportion of isolates expressing vaccine serotypes, with a steady decline of the serotypes included in the 7-valent conjugate vaccine from 31% (1999-2003) to 11% (2011) (P<0.001). Taking together the most recent study years (2009-2011), the potential coverage of the 13-valent conjugate vaccine was 44% and of the 23-valent polysaccharide vaccine was 66%. While erythromycin resistance increased from 8% in 1999-2003 to 18% in 2011 (P<0.001), no significant trend was identified for penicillin non-susceptibility, which had an average value of 18.5%. The serotype distribution found in this study for NIPP was very different from the one previously described for IPD, with only two serotypes in common to the ones responsible for half of each presentation in 2009-2011 - serotypes 3 and 19A. In spite of these differences, the overall prevalence of resistant isolates was similar in NIPP and in IPD. PMID:25075961

  13. Non-Invasive Early Detection and Molecular Analysis of Low X-ray Dose Effects in the Lens

    SciTech Connect

    Goldstein, Lee

    2014-07-02

    This is the Final Progress Report for DOE-funded research project DE-PS02-08ER08-01 titled “Non-Invasive Early Detection and Molecular Analysis of Low X-ray Dose Effects in the Lens”. The project focuses on the effects of low-linear energy transfer (LET) radiation on the ocular lens. The lens is an exquisitely radiosensitive tissue with a highly-ordered molecular structure that is amenable to non-invasive optical study from the periphery. These merits point to the lens as an ideal target for laser-based molecular biodosimetry (MBD). Following exposure to different types of ionizing radiations, the lens demonstrates molecular changes (e.g., oxidation, racemization, crosslinkage, truncation, aggregation, etc.) that impact the structure and function of the long-lived proteins in the cytosol of lens fiber cells. The vast majority of proteins in the lens comprise the highly-ordered crystallins. These highly conserved lens proteins are amongst the most concentrated and stable in the body. Once synthesized, the crystallins are retained in the fiber cell cytoplasm for life. Taken together, these properties point to the lens as an ideal system for quantitative in vivo MBD assessment using quasi-elastic light scattering (QLS) analysis. In this project, we deploy a purpose-designed non-invasive infrared laser QLS instrument as a quantitative tool for longitudinal assessment of pre-cataractous molecular changes in the lenses of living mice exposed to low-dose low-LET radiation compared to non-irradiated sham controls. We hypothesize that radiation exposure will induce dose-dependent changes in the molecular structure of matrix proteins in the lens. Mechanistic assays to ascertain radiation-induced molecular changes in the lens focus on protein aggregation and gene/protein expression patterns. We anticipate that this study will contribute to our understanding of early molecular changes associated with radiation-induced tissue pathology. This study also affords potential for

  14. Partitioned Exhaled Nitric Oxide to Non-Invasively Assess Asthma

    PubMed Central

    Puckett, James L.; George, Steven C.

    2008-01-01

    Asthma is a chronic inflammatory disease of the lungs, characterized by airway hyperresponsiveness. Chronic repetitive bouts of acute inflammation lead to airway wall remodeling and possibly the sequelae of fixed airflow obstruction. Nitric oxide (NO) is a reactive molecule synthesized by NO synthases (NOS). NOS are expressed by cells within the airway wall and functionally, two NOS isoforms exist: constitutive and inducible. In asthma, the inducible isoform is over expressed, leading to increased production of NO, which diffuses into the airway lumen, where it can be detected in the exhaled breath. The exhaled NO signal can be partitioned into airway and alveolar components by measuring exhaled NO at multiple flows and applying mathematical models of pulmonary NO dynamics. The airway NO flux and alveolar NO concentration can be elevated in adults and children with asthma and have been correlated with markers of airway inflammation and airflow obstruction in cross-sectional studies. Longitudinal studies which specifically address the clinical potential of partitioning exhaled NO for diagnosis, managing therapy, and predicting exacerbation are needed. PMID:18718562

  15. Synthesis, characterization and optical properties of nanoparticles

    NASA Astrophysics Data System (ADS)

    Li, Shoutian

    ZnO, Si, silica, Ge, Ga oxide, W oxide and Mo oxide nanoparticles have been synthesized and characterized, and their optical properties have been investigated. These particles were synthesized by a Laser Vaporization and Controlled Condensation (LVCC) technique in a modified diffusion cloud chamber. The particles deposited on smooth substrates reveal highly organized web-like structures with uniform micrometer size pores. The effect of solvents on the web-like structures was also investigated. ZnO nanoparticles were also prepared by wet chemical methods such as the reversed micelle and sol solutions technique. The photoluminescence quantum yield is enhanced 10 times once the surfaces of the ZnO nanoparticles are coated with a layer of stearate molecules. Many techniques have been used to characterize the nanoparticles. SEM gives information about particle size and morphology; X-ray diffraction and Raman spectroscopy determine the crystallinity and crystal structure; XPS and FTIR reveal the surface chemical composition; UV-vis spectroscopy and photoluminescence measurements characterize the optical properties of nanoparticles. Silica nanoparticles, prepared in an amorphous phase, show bright blue photoluminescence upon irradiation with UV light, but the luminescence has a very short lifetime (less than 20 ns). Si nanoparticles, with a diamond-like crystal phase, acquire oxidized-surfaces on exposure to air. The surface-oxidized Si nanocrystals show a short- lived blue emission characteristic of the SiO2 coating and a longer-lived red emission at room temperature. The lifetime of the red emission depends on the emission wavelength. Some substituted benzene molecules and tungsten oxide nanoparticles can quench the red photoluminescence of the Si nanocrystals. Tungsten oxide and molybdenum oxide nanoparticles show photochromic properties: they change color to blue when irradiated. The photons drive a transition from one chemical state to another. The color change of

  16. Invasive versus Non Invasive Methods Applied to Mummy Research: Will This Controversy Ever Be Solved?

    PubMed Central

    Moissidou, Despina; Day, Jasmine; Shin, Dong Hoon; Bianucci, Raffaella

    2015-01-01

    Advances in the application of non invasive techniques to mummified remains have shed new light on past diseases. The virtual inspection of a corpse, which has almost completely replaced classical autopsy, has proven to be important especially when dealing with valuable museum specimens. In spite of some very rewarding results, there are still many open questions. Non invasive techniques provide information on hard and soft tissue pathologies and allow information to be gleaned concerning mummification practices (e.g., ancient Egyptian artificial mummification). Nevertheless, there are other fields of mummy studies in which the results provided by non invasive techniques are not always self-explanatory. Reliance exclusively upon virtual diagnoses can sometimes lead to inconclusive and misleading interpretations. On the other hand, several types of investigation (e.g., histology, paleomicrobiology, and biochemistry), although minimally invasive, require direct contact with the bodies and, for this reason, are often avoided, particularly by museum curators. Here we present an overview of the non invasive and invasive techniques currently used in mummy studies and propose an approach that might solve these conflicts. PMID:26345295

  17. The Role of RNAs and microRNAs in Non-Invasive Prenatal Diagnosis

    PubMed Central

    Farina, Antonio

    2014-01-01

    In this paper, all possible clinical applications of circulating mRNA and miRNA for non-invasive prenatal diagnosis appearing in the medical literature so far are described. Data from the literature have also been reported and commented on along with some possible future applications. PMID:26237384

  18. Differential radioactivity monitor for non-invasive detection of ocular melanoma

    DOEpatents

    Lambrecht, R.M.; Packer, S.

    1982-09-23

    There is described an apparatus and method for diagnosing ocular cancer that is both non-invasive and accurate which comprises two radiation detectors positioned before each of the patient's eyes which will measure the radiation level produced in each eye after the administration of a tumor-localizing radiopharmaceutical such as gallium-67.

  19. Can non-invasive measurement of gut oxygenation predict necrotizing enterocolitis in preterm infants?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Factors that contribute to the development of NEC include hypoperfusion or decreased oxygenation of splanchnic tissue. Near-Infrared Spectroscopy (NIRS) will be used to assess gut oxygenation non-invasively. Typically NIRS is primarily used for cerebral hemodynamic monitoring; we intend to apply it ...

  20. Non Invasive Biomedical Analysis - Breath Networking Session at PittCon 2011, Atlanta, Georgia

    EPA Science Inventory

    This was the second year that our breath colleagues organized a networking session at the Pittsburgh Conference and Exposition or ''PittCon'' (http://www.pincon.org/).This time it was called "Non-invasive Biomedical Analysis" to broaden the scope a bit, but the primary focus rema...

  1. Non-Invasive Management of Madura Foot with Oral Posaconazole and Ciprofloxacin

    PubMed Central

    Sharma, Amit M.; Sharma, Namita; Nat, Amritpal; Rane, Meghan; Endy, Timothy P.

    2014-01-01

    Madura foot is a chronic infection caused by fungus and/or bacteria. Traditionally, treatment has been surgical debridement or amputation. Non-invasive management with long-term antimicrobials alone has been reported as successful. We report a case of Madura foot in a Somali refugee successfully managed with oral posaconazole and ciprofloxacin. PMID:25349373

  2. Aortic stenosis in adults. Non-invasive estimation of pressure differences by continuous wave Doppler echocardiography.

    PubMed Central

    Hegrenaes, L; Hatle, L

    1985-01-01

    The peak and mean aortic transvalvar pressure differences measured invasively and non-invasively by continuous wave Doppler echocardiography were compared in 87 consecutive patients with aortic stenosis. The mean values were calculated from the maximal velocities of the aortic jet recorded with a spectral display of the Doppler frequency shifts and by applying a modified Bernoulli equation. Technically satisfactory velocity curves for estimating the mean pressure differences could not be obtained in three patients and invasive measurements were not obtained in two. In all patients the peak transvalvar pressure difference was calculated since the aortic jet was identified non-invasively. The peak and mean pressure differences measured invasively and non-invasively correlated well--with only minor underestimation of the pressure differences measured with the Doppler technique--regardless of age, sex, and the presence or absence of aortic valvar regurgitation, or other valvar lesions. With a systematic search for the highest velocities in the aortic jet and with on line spectral analysis of the Doppler frequencies the peak and the mean aortic pressure differences can be determined non-invasively with a high degree of precision in almost all patients. Images PMID:4052281

  3. Application of quantum dot nanoparticles for potential non-invasive bio-imaging of mammalian spermatozoa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Various obstacles are encountered by mammalian spermatozoa during their journey through the female genital tract, and only few or none will reach the site of fertilization. Currently, there are limited technical approaches for non-invasive investigation of spermatozoa migration after insemination. A...

  4. Who is Who? Non-invasive Methods to Individually Sex and Mark Altricial Chicks

    PubMed Central

    Adam, Iris; Scharff, Constance; Honarmand, Mariam

    2014-01-01

    Many experiments require early determination of offspring's sex as well as early marking of newborns for individual recognition. According to animal welfare guidelines, non-invasive techniques should be preferred whenever applicable. In our group, we work on different species of song birds in the lab and in the field, and we successfully apply non-invasive methods to sex and individually mark chicks. This paper presents a comprehensive non-invasive tool-box. Sexing birds prior to the expression of secondary sexual traits requires the collection of DNA-bearing material for PCR. We established a quick and easy method to sex birds of any age (post hatching) by extracting DNA from buccal swabs. Results can be obtained within 3 hours. For individual marking chick's down feathers are trimmed in specific patterns allowing fast identification within the hatching order. This set of methods is easily applicable in a standard equipped lab and especially suitable for working in the field as no special equipment is required for sampling and storage. Handling of chicks is minimized and marking and sexing techniques are non-invasive thereby supporting the RRR-principle of animal welfare guidelines. PMID:24893585

  5. Who is who? Non-invasive methods to individually sex and mark altricial chicks.

    PubMed

    Adam, Iris; Scharff, Constance; Honarmand, Mariam

    2014-01-01

    Many experiments require early determination of offspring's sex as well as early marking of newborns for individual recognition. According to animal welfare guidelines, non-invasive techniques should be preferred whenever applicable. In our group, we work on different species of song birds in the lab and in the field, and we successfully apply non-invasive methods to sex and individually mark chicks. This paper presents a comprehensive non-invasive tool-box. Sexing birds prior to the expression of secondary sexual traits requires the collection of DNA-bearing material for PCR. We established a quick and easy method to sex birds of any age (post hatching) by extracting DNA from buccal swabs. Results can be obtained within 3 hours. For individual marking chick's down feathers are trimmed in specific patterns allowing fast identification within the hatching order. This set of methods is easily applicable in a standard equipped lab and especially suitable for working in the field as no special equipment is required for sampling and storage. Handling of chicks is minimized and marking and sexing techniques are non-invasive thereby supporting the RRR-principle of animal welfare guidelines. PMID:24893585

  6. Non-invasive glucose measurement technologies: an update from 1999 to the dawn of the new millennium.

    PubMed

    Khalil, Omar S

    2004-10-01

    There are three main issues in non-invasive (NI) glucose measurements: namely, specificity, compartmentalization of glucose values, and calibration. There has been progress in the use of near-infrared and mid-infrared spectroscopy. Recently new glucose measurement methods have been developed, exploiting the effect of glucose on erythrocyte scattering, new photoacoustic phenomenon, optical coherence tomography, thermo-optical studies on human skin, Raman spectroscopy studies, fluorescence measurements, and use of photonic crystals. In addition to optical methods, in vivo electrical impedance results have been reported. Some of these methods measure intrinsic properties of glucose; others deal with its effect on tissue or blood properties. Recent studies on skin from individuals with diabetes and its response to stimuli, skin thermo-optical response, peripheral blood flow, and red blood cell rheology in diabetes shed new light on physical and physiological changes resulting from the disease that can affect NI glucose measurements. There have been advances in understanding compartmentalization of glucose values by targeting certain regions of human tissue. Calibration of NI measurements and devices is still an open question. More studies are needed to understand the specific glucose signals and signals that are due to the effect of glucose on blood and tissue properties. These studies should be performed under normal physiological conditions and in the presence of other co-morbidities. PMID:15628820

  7. Crown Preservation of the Mandibular First Molar Tooth Impacts the Strength and Stiffness of Three Non-Invasive Jaw Fracture Repair Constructs in Dogs

    PubMed Central

    Lothamer, Charles; Snyder, Christopher John; Duenwald-Kuehl, Sarah; Kloke, John; McCabe, Ronald P.; Vanderby, Ray

    2015-01-01

    Repairing mandibular body fractures presents unique challenges not encountered when repairing long bones. Large tooth roots and the presence of the inferior alveolar neurovascular bundle limit safe placement for many types of orthopedic implants. Use of non-invasive fracture repair methods have increasingly become popular and have proven safe and effective at achieving bone healing. Non-invasive fixation constructs have not been tested in dogs using cantilevered bending. Furthermore, non-invasive fracture repair constructs have not been tested at the location of a common fracture location – the mandibular first molar tooth (M1). The objectives of this study were to test the strength and stiffness of three non-invasive mandibular fracture repair constructs and to characterize the impact that tooth crown preservation has on fixation strength for fractures occurring at the M1 location. Specimens were assigned to three treatment groups: (1) composite only, (2) interdental wiring and composite (IWC), and (3) transmucosal fixation screw and composite. For each pair of mandibles, one mandible received crown amputation at the alveolar margin to simulate the effect of crown loss on fixation strength and stiffness. Regardless of the status of crown presence, IWC demonstrated the greatest bending stiffness and load to failure. With the crown removed, IWC was significantly stronger compared to other treatments. All fixation constructs were stiffer when the tooth crown was preserved. In fractures at this location, retaining the tooth crown of M1 significantly increases stiffness of interdental wiring with composite and transmucosal screw with composite constructs. If the crown of M1 was removed, IWC was significantly stronger than the other two forms of fixation. PMID:26664947

  8. Characterization of commercial fiber optic connectors - Preliminary report

    SciTech Connect

    Andrews, Larry A.; Williams, Randy J.

    1998-09-01

    Several types of commercial fiber optic connectors were characterized for potential use in a Sandia designed Laser Diode Ignition (LDI) system. The characterization included optical performance while the connectors were subjected to the more dynamic environmental conditions experienced in weapons applications. The environmental testing included temperature cycling, random vibration, and mechanical shock. This report presents a performance assessment of the fiber optic connectors and fiber included in the characterization. The desirable design features are described for a fiber optic connector that must survive the dynamic environment of weapon systems. The more detailed performance of each connector type will be included as resources permit.

  9. Validation and characterization of optical redox ratio measurements with a microplate reader in breast cancer cells

    NASA Astrophysics Data System (ADS)

    Cannon, Taylor M.; Shah, Amy T.; Skala, Melissa C.

    2015-02-01

    There is a need for accurate, high-throughput measures to gauge the efficacy of potential drugs in living cells. Metabolism is an early marker of drug response in cells, and NADH and FAD are autofluorescent cellular metabolic coenzymes that can be non-invasively monitored using optical techniques. Relative rates of glycolysis and oxidative phosphorylation in a cell are quantified by the redox ratio, defined as the autofluorescence intensity of NADH divided by that of FAD. Microplate readers are high-throughput instruments that can rapidly measure NADH and FAD autofluorescence intensities for hundreds of wells, and are capable of identifying receptor status and resolving drug response in breast cancer cell lines. This study tests the accuracy and repeatability of plate reader experiments measuring the redox ratio in breast cancer cell lines. NADH and FAD fluorescence levels remained constant over the course of multiple measurements (p<0.1), ruling out the incidence of photobleaching. The contribution of media to background fluorescence signal was also investigated. Media fluorescence levels for both coenzymes were significantly lower (p<0.0001) than those from wells containing cells, and replacing the media with saline resulted in the same redox ratio trends among cell lines as initial measurements with media. Following treatment with carbonyl cyanide p-fluorodeoxyphenylhydrazone (FCCP), an oxidative phosphorylation inhibitor, the redox ratio decreased (p<0.05), validating NADH and FAD as the primary fluorescence sources. These findings verify that autofluorescence measurements taken by microplate readers accurately and reliably characterize NADH and FAD fluorescence, validating their promise in the areas of metabolic monitoring and drug development.

  10. Halogen Occultation Experiment (HALOE) optical filter characterization

    NASA Technical Reports Server (NTRS)

    Harvey, Gale A.

    1989-01-01

    The Halogen Occultation Experiment (HALOE) is a solar occultation experiment that will fly on the Upper Atmosphere Research Satellite to measure mixing ratio profiles of O3, H2O, NO2, NO, CH4, HCl, and HF. The inversion of the HALOE data will be critically dependent on a detailed knowledge of eight optical filters. A filter characterization program was undertaken to measure in-band transmissions, out-of-band transmissions, in-band transmission shifts with temperature, reflectivities, and age stability. Fourier Transform Infrared Spectrometers were used to perform measurements over the spectral interval 400/cm to 6300/cm (25 micrometers to 1.6 micrometers). Very high precision (0.1 percent T) in-band measurements and very high resolution (0.0001 percent T) out-of-band measurements have been made. The measurements revealed several conventional leaks at 0.01 percent transmission and greatly enhanced (1,000) leaks to the 2-element filters when placed in a Fabry-Perot cavity. Filter throughput changes by 5 percent for a 25 C change in filter temperature.

  11. Non-invasive assessment of sciatic nerve stiffness during human ankle motion using ultrasound shear wave elastography.

    PubMed

    Andrade, Ricardo J; Nordez, Antoine; Hug, François; Ates, Filiz; Coppieters, Michel W; Pezarat-Correia, Pedro; Freitas, Sandro R

    2016-02-01

    Peripheral nerves are exposed to mechanical stress during movement. However the in vivo mechanical properties of nerves remain largely unexplored. The primary aim of this study was to characterize the effect of passive dorsiflexion on sciatic nerve shear wave velocity (an index of stiffness) when the knee was in 90° flexion (knee 90°) or extended (knee 180°). The secondary aim was to determine the effect of five repeated dorsiflexions on the nerve shear wave velocity. Nine healthy participants were tested. The repeatability of sciatic nerve shear wave velocity was good for both knee 90° and knee 180° (ICCs≥0.92, CVs≤8.1%). The shear wave velocity of the sciatic nerve significantly increased (p<0.0001) during dorsiflexion when the knee was extended (knee 180°), but no changes were observed when the knee was flexed (90°). The shear wave velocity-angle relationship displayed a hysteresis for knee 180°. Although there was a tendency for the nerve shear wave velocity to decrease throughout the repetition of the five ankle dorsiflexions, the level of significance was not reached (p=0.055). These results demonstrate that the sciatic nerve stiffness can be non-invasively assessed during passive movements. In addition, the results highlight the importance of considering both the knee and the ankle position for clinical and biomechanical assessment of the sciatic nerve. This non-invasive technique offers new perspectives to provide new insights into nerve mechanics in both healthy and clinical populations (e.g., specific peripheral neuropathies). PMID:26725218

  12. Hemi-spatial neglect rehabilitation using non-invasive brain stimulation: or how to modulate the disconnection syndrome?

    PubMed

    Jacquin-Courtois, S

    2015-09-01

    Hemi-spatial neglect syndrome is common and sometimes long-lasting. It is characterized by a deficit in the use and awareness of one side of space, most often consecutive to a right hemisphere injury, mainly in the parietal region. Acknowledging the different types and all clinical characteristics is essential for an appropriate evaluation and adapted rehabilitation care management, especially as it constitutes a predictive factor of a poor functional prognosis. Some new approaches have been developed in the last fifteen years in the field of hemi-spatial neglect rehabilitation, where non-invasive brain stimulation (TMS and tDCS) holds an important place. Today's approaches of unilateral spatial neglect modulation via non-invasive brain stimulation are essentially based on the concept of inter-hemispheric inhibition, suggesting an over-activation of the contralesional hemisphere due to a decrease of the inhibiting influences of the injured hemisphere. Several approaches may then be used: stimulation of the injured right hemisphere, inhibition of the hyperactive left hemisphere, or a combination of both. Results are promising, but the following complementary aspects must be refined before a more systematic application: optimal stimulation protocol, individual management according to the injured region, intensity, duration and frequency of care management, delay post-stroke before the beginning of treatment, combination of different approaches, as well as prognostic and efficacy criteria. An encouraging perspective for the future is the combination of several types of approaches, which would be largely facilitated by the improvement of fundamental knowledge on neglect mechanisms, which could in the future refine the choice for the most appropriate treatment(s) for a given patient. PMID:26303954

  13. Non-Invasive Molecular Imaging of Fibrosis Using a Collagen-Targeted Peptidomimetic of the Platelet Collagen Receptor Glycoprotein VI

    PubMed Central

    Loyau, Stéphane; Meulemans, Alain; Louedec, Liliane; Bantsimba-Malanda, Claudie; Hervatin, Florence; Marchal-Somme, Joëlle; Michel, Jean Baptiste; Le Guludec, Dominique; Billiald, Philippe; Jandrot-Perrus, Martine

    2009-01-01

    Background Fibrosis, which is characterized by the pathological accumulation of collagen, is recognized as an important feature of many chronic diseases, and as such, constitutes an enormous health burden. We need non-invasive specific methods for the early diagnosis and follow-up of fibrosis in various disorders. Collagen targeting molecules are therefore of interest for potential in vivo imaging of fibrosis. In this study, we developed a collagen-specific probe using a new approach that takes advantage of the inherent specificity of Glycoprotein VI (GPVI), the main platelet receptor for collagens I and III. Methodology/Principal Findings An anti-GPVI antibody that neutralizes collagen-binding was used to screen a bacterial random peptide library. A cyclic motif was identified, and the corresponding peptide (designated collagelin) was synthesized. Solid-phase binding assays and histochemical analysis showed that collagelin specifically bound to collagen (Kd 10−7 M) in vitro, and labelled collagen fibers ex vivo on sections of rat aorta and rat tail. Collagelin is therefore a new specific probe for collagen. The suitability of collagelin as an in vivo probe was tested in a rat model of healed myocardial infarctions (MI). Injecting Tc-99m-labelled collagelin and scintigraphic imaging showed that uptake of the probe occurred in the cardiac area of rats with MI, but not in controls. Post mortem autoradiography and histological analysis of heart sections showed that the labeled areas coincided with fibrosis. Scintigraphic molecular imaging with collagelin provides high resolution, and good contrast between the fibrotic scars and healthy tissues. The capacity of collagelin to image fibrosis in vivo was confirmed in a mouse model of lung fibrosis. Conclusion/Significance Collagelin is a new collagen-targeting agent which may be useful for non-invasive detection of fibrosis in a broad spectrum of diseases. PMID:19440310

  14. Non-invasive detection of candidate pregnancy protein biomarkers in the feces of captive polar bears (Ursus maritimus).

    PubMed

    Curry, E; Stoops, M A; Roth, T L

    2012-07-15

    Currently, there is no method of accurately and non-invasively diagnosing pregnancy in polar bears. Specific proteins may exhibit altered profiles in the feces of pregnant bears, but predicting appropriate candidate proteins to investigate is speculative at best. The objective of this study was to identify potential pregnancy biomarker proteins based on their increased abundance in the feces of pregnant polar bears compared to pseudopregnant females (controls) using two-dimensional in-gel electrophoresis (2D-DIGE) and mass spectrometry (MS). Three 2D-DIGE gels were performed to evaluate fecal protein profiles from controls (n=3) and pregnant polar bears (n=3). There were 2224.67±52.39 (mean±SEM) spots resolved per gel. Of these, only five proteins were elevated in the pregnant group (P<0.05), and seven additional spots tended to be higher (0.0599.9% confidence interval. The 11 spots represented seven distinct proteins, five of which were significantly more abundant in the pregnant group: IgGFc-binding protein, filamin-C, carboxypeptidase B, transthyretin, and immunoglobulin heavy chain variable region. To our knowledge, this was the first study that employed 2D-DIGE to identify differentially expressed proteins in fecal samples to characterize a physiological condition other than those related to gastrointestinal disorders. These promising results provided a strong foundation for ensuing efforts to develop a non-invasive pregnancy assay for use in both captive and wild polar bears. PMID:22538002

  15. Attitudes Towards Non-Invasive Prenatal Testing for Aneuploidy Among United States Adults of Reproductive Age

    PubMed Central

    Sayres, Lauren C.; Goodspeed, Taylor A.; Cho, Mildred K.

    2014-01-01

    Objective(s) To determine how adults in the United States (US) view non-invasive prenatal testing using cell-free fetal DNA (cffDNA testing) in order to help estimate uptake. Study Design A national sample of 1,861 US-based adults was surveyed using a validated online survey instrument. The survey was administered by a commercial survey research company. Respondents were randomized to receive a survey about prenatal testing for trisomy 13 and 18 or trisomy 21. Participants were asked to select among testing modalities, including cffDNA testing, and rank the features of testing that they considered most important to decision making. Results There was substantive interest in the use of cffDNA testing rather than traditional screening mechanisms with a minority of respondents reporting that they would support the use of both methods in combination. The lower rates of false negative and false positive test results and the ability to use the test earlier in the pregnancy were the most highly rated benefits of cffDNA testing. Participants expressed strong support for diagnostic confirmation via invasive testing after a positive result from either screening or cffDNA testing. However, almost one-third of participants reported that they would not endorse the use of either invasive or non-invasive prenatal testing. Conclusion(s) There appears to be support for uptake of non-invasive prenatal tests. Clinical guidelines should therefor go forward in providing guidance on how to integrate non-invasive methods into current standard of care. However, our findings indicate that even when accuracy, which is rated by patients as the most important aspect of prenatal testing, is significantly improved over existing screening methods and testing is offered non-invasively, the number of individuals who reported that they would decline any testing remained the same. Attention should therefor be directed at ensuring that the right of informed refusal of prenatal testing is not impacted

  16. Synthesis, characterization and optical applications of nanomaterials

    NASA Astrophysics Data System (ADS)

    Xu, Fen

    Nanomaterials have been studied extensively due to their potential application in electronics, photonics and nanodevices. There are a wide variety of methods developed to create the nano-scale materials. Chemical colloidal synthesis is the way most used since it is reproducible and high efficiency. Nanoparticles lie at the heart of nanoscience for their novel electronic, magnetic and optical properties. In this dissertation, there are two parts where researches have been performed based on the synthesis of metal and semiconductor nanoparticles. In part I, Semiconductor type-II core-shell quantum dots (QDs) ZnO-CdS have been synthesized by chemical colloidal method which was carried out in a two-step process. We initially synthesized ZnO core nanoparticles and overcoat them with CdS shell. UV-Visible spectra, photoluminescence spectra (PL), high resolution TEM images and X-ray microanalysis for composition studies of the core-shell nanoparticles were characterized. PL lifetime measurements showed this type-II ZnO-CdS core-shell QDs presented extended exciton lifetime due to the spatial separation of electrons and holes between the core and the shell, which opens various useful applications in biosensors and photovoltaic devices. In part II, normal Raman (NR) and surface enhanced Raman scattering (SERS) spectra of 3-hydroxyflavone (3-HF) have been measured. The SERS spectra were obtained both on a Ag electrode surface and on Ag colloidal nanoparticles. The experimental results support the DFT geometry calculations, which show that an adatom site at the vertex of Ag20 cluster binding with the 3-HF molecular plane tilted at an angle of about 53° to the surface is a low-energy structure. This is consistent with the enhancement of in-plane vibrational modes. Furthermore, the effect of fluence level on the discoloration of marble surfaces after the removal of the encrustation by 355 nm laser pulses was comparatively studied. Considering the thermochemical reaction

  17. Hollow-core waveguide characterization by optically induced particle transport.

    PubMed

    Measor, Philip; Kühn, Sergei; Lunt, Evan J; Phillips, Brian S; Hawkins, Aaron R; Schmidt, Holger

    2008-04-01

    We introduce a method for optical characterization of hollow-core optical waveguides. Radiation pressure exerted by the waveguide modes on dielectric microspheres is used to analyze salient properties such as propagation loss and waveguide mode profiles. These quantities were measured for quasi-single-mode and multimode propagation in on-chip liquid-filled hollow-core antiresonant reflecting optical waveguides. Excellent agreement with analytical and numerical models is found, demonstrating that optically induced particle transport provides a simple, inexpensive, and nondestructive alternative to other characterization methods. PMID:18382513

  18. Broadband time-resolved diffuse optical spectrometer for clinical diagnostics: characterization and in-vivo measurements in the 600-1350 nm spectral range

    NASA Astrophysics Data System (ADS)

    Konugolu Venkata Sekar, Sanathana; Farina, Andrea; Martinenghi, Edoardo; Dalla Mora, Alberto; Taroni, Paola; Pifferi, Antonio; Durduran, Turgut; Pagliazzi, Marco; Lindner, Claus; Farzam, Parisa; Mora, Mireia; Squarcia, Mattia; Urbano-Ispizua, A.

    2015-07-01

    We report on the design, performance assessment, and first in vivo measurement of a Time-Resolved Diffuse Optical system for broadband (600-1350 nm) nm measurement of absorption and scattering spectra of biological tissues for non-invasive clinical diagnostics. Two strategies to reduce drift and enhance responsivity are adopted. The system was enrolled in a first in vivo test phase on healthy volunteers, carrying out non-invasive, in vivo quantification of key tissue constituents (oxy- and deoxy-hemoglobin, water, lipids, collagen) and tissue micro-structure (scatterer size and density).

  19. Fatal brain gas embolism during non-invasive positive pressure ventilation

    PubMed Central

    Rivara, Claire B; Chevrolet, Jean-Claude; Gasche, Yvan; Charbonney, Emmanuel

    2008-01-01

    Gas embolism is a dreaded complication following invasive medical procedures, traumatic lung injury and decompression accidents. We report a case of fatal gas embolism following the use of non-invasive ventilation (NIV) with bilevel positive airway pressure (BiPAP). The patient initially underwent left bronchial artery embolisation for massive haemoptysis in the context of severe tuberculotic sequels. Under NIV and after heavy coughing he became hemiparetic and his level of consciousness suddenly dropped. Computed tomography of the brain showed multiple air embolism and ischaemic lesions were confirmed by magnetic resonance imaging. Echocardiographic investigations showed no intracardiac defect. Vasculo-pulmonary abnormalities in the context of heavy coughing and non-invasive ventilation may have played a major role in the occurrence of this event. New neurological events in a patient with tuberculotic sequels or any known vascular pulmonary abnormalities and NIV should raise the suspicion of brain gas embolism. PMID:21716825

  20. Non-invasive online detection of microbial lysine formation in stirred tank bioreactors by using calorespirometry.

    PubMed

    Regestein, Lars; Maskow, Thomas; Tack, Andreas; Knabben, Ingo; Wunderlich, Martin; Lerchner, Johannes; Büchs, Jochen

    2013-05-01

    Non-invasive methods for online monitoring of biotechnological processes without compromising the integrity of the reactor system are very important to generate continuous data. Even though calorimetry has been used in conventional biochemical analysis for decades, it has not yet been specifically applied for online detection of product formation at technical scale. Thus, this article demonstrates a calorespirometric method for online detection of microbial lysine formation in stirred tank bioreactors. The respective heat generation of two bacterial strains, Corynebacterium glutamicum ATCC 13032 (wild-type) and C. glutamicum DM1730 (lysine producer), was compared with the O2 -consumption in order to determine whether lysine was formed. As validation of the proposed calorespirometric method, the online results agreed well with the offline measured data. This study has proven that calorespirometry is a viable non-invasive technique to detect product formation at any time point. PMID:23280310

  1. Non-invasive mechanical ventilation: the benefits of the BiPAP system.

    PubMed

    Teba, L; Marks, P; Benzo, R

    1996-01-01

    Many of the complications with endotracheal intubation and invasive mechanical ventilation can be avoided with the use of non-invasive mechanical ventilation (NIMV). This technique has been especially successful in treating patients with acute respiratory failure (ARF). NIMV improves gas exchange, avoids complications caused by endotracheal intubation, and allows patients to talk and take medications orally. This article reviews our experiences treating 27 patients with ARF with a BiPAP (bi-level positive airway pressure) ventilator. This is a portable unit which allows for selection of different modes of ventilation and adjustment of inspiratory and expiratory pressures. Non-invasive mechanical ventilation should be considered in patients presenting with ARF who are hemodynamically stable and in whom spontaneous breathing is preserved. PMID:8599242

  2. [Cerebral arteriovenous malformations: value of the non invasive vascular imaging techniques].

    PubMed

    Leclerc, X; Gauvrit, J Y; Trystram, D; Reyns, N; Pruvo, J P; Meder, J F

    2004-12-01

    Imaging evaluation of cerebral arteriovenous malformations (AVM) requires selective visualization of the different compartments of the malformation in order to select the therapeutic management. Conventional angiography remains the reference to analyze intracranial vessel conspicuity but non-invasive methods constitute an excellent alternative. Among these techniques, CT angiography is rarely used because of the need to inject iodinated contrast material and because of irradiation. MR angiography provides useful information and can be performed using several techniques: time of flight with or without contrast material injection, phase contrast, three-dimensional (3D) gradient echo acquisition after contrast material injection and, more recently, MR digital subtraction angiography. The purpose of this review article is to summarize the different non-invasive techniques for vascular imaging and to analyze the usefulness of these techniques for the assessment of brain AVMs. PMID:15687950

  3. Perspectives on emerging biomarkers for non-invasive assessment of embryo viability in assisted reproduction.

    PubMed

    Aydiner, F; Yetkin, C E; Seli, E

    2010-03-01

    A key step in assisted reproduction is the assessment of embryo viability in order to identify the embryo(s) most likely to result in pregnancy. Currently used embryo assessment systems are largely based on morphology and cleavage rate. While these systems have been pivotal in improving implantation and pregnancy rates and reducing multiple gestations, their precision is still insufficient. The limitations of strategies based on morphology have led to the investigation of adjunctive technologies for non-invasive assessment of embryo viability in assisted reproduction. These include the measurement of glucose, pyruvate, or amino acid levels in the embryo culture media, assessment of oxygen consumption by the embryo, genomic and proteomic profiling, and most recently, analytical examination of the embryonic metabolome. As the number of ART cycles increases worldwide, improvements in the ability to quickly and non-invasively identify the best embryos for transfer become an increasingly more important goal for reproductive medicine. PMID:20196727

  4. Non-invasive determination of cardiac output by Doppler echocardiography and electrical bioimpedance.

    PubMed Central

    Northridge, D B; Findlay, I N; Wilson, J; Henderson, E; Dargie, H J

    1990-01-01

    Cardiac output measured by thermodilution in 25 patients within 24 hours of acute myocardial infarction was compared with cardiac output measured by Doppler echocardiography (24 patients) and electrical bioimpedance (25 patients). The mean (range) cardiac outputs measured by Doppler (4.03 (2.2-6.0) 1/min) and electrical bioimpedance (3.79 (1.1-6.2) 1/min) were similar to the mean thermodilution value (3.95 (2.1-6.2) 1/min). Both non-invasive techniques agreed closely with thermodilution in most patients. None the less, three results with each method disagreed with thermodilution by more than 1 1/min. Both non-invasive techniques were reproducible and accurate in most patients with acute myocardial infarction. Doppler echocardiography was time consuming and technically demanding. Electrical bioimpedance was simple to use and had the additional advantage of allowing continuous monitoring of the cardiac output. PMID:2317415

  5. An Investigation of Pulse Transit Time as a Non-Invasive Blood Pressure Measurement Method

    NASA Astrophysics Data System (ADS)

    McCarthy, B. M.; O'Flynn, B.; Mathewson, A.

    2011-08-01

    The objective of this paper is to examine the Pulse Transit Method (PTT) as a non-invasive means to track Blood Pressure over a short period of time. PTT was measured as the time it takes for an ECG R-wave to propagate to the finger, where it is detected by a photoplethysmograph sensor. The PTT method is ideal for continuous 24-hour Blood Pressure Measurement (BPM) since it is both cuff-less and non-invasive and therefore comfortable and unobtrusive for the patient. Other techniques, such as the oscillometric method, have shown to be accurate and reliable but require a cuff for operation, making them unsuitable for long term monitoring. Although a relatively new technique, the PTT method has shown to be able to accurately track blood pressure changes over short periods of time, after which re-calibration is necessary. The purpose of this study is to determine the accuracy of the method.

  6. A non-invasive technique for rapid extraction of DNA from fish scales.

    PubMed

    Kumar, Ravindra; Singh, Poonam Jayant; Nagpure, N S; Kushwaha, Basdeo; Srivastava, S K; Lakra, W S

    2007-11-01

    DNA markers are being increasingly used in studies related to population genetics and conservation biology of endangered species. DNA isolation for such studies requires a source of biological material that is easy to collect, non-bulky and reliable. Further, the sampling strategies based on non-invasive procedures are desirable, especially for the endangered fish species. In view of above, a rapid DNA extraction method from fish scales has been developed with the use of a modified lysis buffer that require about 2 hr duration. This methodology is non-invasive, less expensive and reproducible with high efficiency of DNA recovery. The DNA extracted by this technique, have been found suitable for performing restriction enzyme digestion and PCR amplification. Therefore, the present DNA extraction procedure can be used as an alternative technique in population genetic studies pertaining to endangered fish species. The technique was also found equally effective for DNA isolation from fresh, dried and ethanol preserved scales. PMID:18072545

  7. [Non-invasive mechanical ventilation in the treatment of acute heart failure].

    PubMed

    Alfonso Megido, Joaquín; González Franco, Alvaro

    2014-03-01

    When acute heart failure progresses and there is acute cardiogenic pulmonary edema, routine therapeutic measures should be accompanied by other measures that help to correct oxygenation of the patient. The final and most drastic step is mechanical ventilation. Non-invasive ventilation has been developed in the last few years as a method that attempts to improve oxygenation without the need for intubation, thus, in theory, reducing morbidity and mortality in these patients. The present article describes the controversies surrounding the results of this technique and discusses its indications. The article also discusses how to start non-invasive ventilation in patients with acute pulmonary edema from a practical point of view. PMID:24930085

  8. Non-invasive brain stimulation in children: applications and future directions

    PubMed Central

    Rajapakse, Thilinie; Kirton, Adam

    2013-01-01

    Transcranial magnetic stimulation (TMS) is a neurostimulation and neuromodulation technique that has provided over two decades of data in focal, non-invasive brain stimulation based on the principles of electromagnetic induction. Its minimal risk, excellent tolerability and increasingly sophisticated ability to interrogate neurophysiology and plasticity make it an enviable technology for use in pediatric research with future extension into therapeutic trials. While adult trials show promise in using TMS as a novel, non-invasive, non-pharmacologic diagnostic and therapeutic tool in a variety of nervous system disorders, its use in children is only just emerging. TMS represents an exciting advancement to better understand and improve outcomes from disorders of the developing brain. PMID:24163755

  9. Non-invasive determination of the complete elastic moduli of spider silks

    NASA Astrophysics Data System (ADS)

    Koski, Kristie J.; Akhenblit, Paul; McKiernan, Keri; Yarger, Jeffery L.

    2013-03-01

    Spider silks possess nature’s most exceptional mechanical properties, with unrivalled extensibility and high tensile strength. Unfortunately, our understanding of silks is limited because the complete elastic response has never been measured—leaving a stark lack of essential fundamental information. Using non-invasive, non-destructive Brillouin light scattering, we obtain the entire stiffness tensors (revealing negative Poisson’s ratios), refractive indices, and longitudinal and transverse sound velocities for major and minor ampullate spider silks: Argiope aurantia, Latrodectus hesperus, Nephila clavipes, Peucetia viridans. These results completely quantify the linear elastic response for all possible deformation modes, information unobtainable with traditional stress-strain tests. For completeness, we apply the principles of Brillouin imaging to spatially map the elastic stiffnesses on a spider web without deforming or disrupting the web in a non-invasive, non-contact measurement, finding variation among discrete fibres, junctions and glue spots. Finally, we provide the stiffness changes that occur with supercontraction.

  10. Non-invasive determination of the complete elastic moduli of spider silks.

    PubMed

    Koski, Kristie J; Akhenblit, Paul; McKiernan, Keri; Yarger, Jeffery L

    2013-03-01

    Spider silks possess nature's most exceptional mechanical properties, with unrivalled extensibility and high tensile strength. Unfortunately, our understanding of silks is limited because the complete elastic response has never been measured-leaving a stark lack of essential fundamental information. Using non-invasive, non-destructive Brillouin light scattering, we obtain the entire stiffness tensors (revealing negative Poisson's ratios), refractive indices, and longitudinal and transverse sound velocities for major and minor ampullate spider silks: Argiope aurantia, Latrodectus hesperus, Nephila clavipes, Peucetia viridans. These results completely quantify the linear elastic response for all possible deformation modes, information unobtainable with traditional stress-strain tests. For completeness, we apply the principles of Brillouin imaging to spatially map the elastic stiffnesses on a spider web without deforming or disrupting the web in a non-invasive, non-contact measurement, finding variation among discrete fibres, junctions and glue spots. Finally, we provide the stiffness changes that occur with supercontraction. PMID:23353627

  11. Non-invasive measurements of hemoglobin + myoglobin, their oxygenation and NIR light pathlength in heart in vivo by diffuse reflectance spectroscopy

    NASA Astrophysics Data System (ADS)

    Gussakovsky, Eugene; Jilkina, Olga; Yang, Yanmin; Kupriyanov, Valery

    2009-02-01

    The existing non-invasive optical methods of the hemoglobin (Hb) and myoglobin (Mb) estimation in cardiac tissues imply knowledge of the light pathlength (L) when various modifications of Lambert-Beer law for either spectrophotometry or light diffuse reflectance is applied. For Hb and/or Mb quantification in tissue, a few invasive (biochemical) approaches were applied. For L (differential pathlength factor; DPF) determination in tissue, special optical methods were used. No approaches have been proposed to simultaneously and non-invasively determine Hb/Mb and L in cardiac or other muscle tissues. In the present study, the first derivative of the NIR diffuse reflectance spectrum is shown to be effective in simultaneous determination of Hb+Mb concentration (in mM) and L (in mm) in cardiac tissue in vivo. The results showed that measured in a few minutes in a normal pig heart in vivo the total Hb+Mb concentration was 0.9-1.2 mM of heme, tissue oxygen saturation parameter (OSP) was approximately 65%, and DPF at 700-965 nm was of 2.7-2.8. At the experimental ischemia, total [Hb+Mb] decreased by 25%, OSP reduced to zero, while DPF did not change. These results correlated with the previously published. The method may be applied during open-heart surgery, heart studies ex vivo or to any muscle tissue to continuously and non-invasively monitor the [Hb+Mb] content and oxygenation as well as L, which may reflect the changes in tissue structure.

  12. Non-invasive Brain Stimulation, a Tool to Revert Maladaptive Plasticity in Neuropathic Pain.

    PubMed

    Naro, Antonino; Milardi, Demetrio; Russo, Margherita; Terranova, Carmen; Rizzo, Vincenzo; Cacciola, Alberto; Marino, Silvia; Calabro, Rocco S; Quartarone, Angelo

    2016-01-01

    Neuromodulatory effects of non-invasive brain stimulation (NIBS) have been extensively studied in chronic pain. A hypothetic mechanism of action would be to prevent or revert the ongoing maladaptive plasticity within the pain matrix. In this review, the authors discuss the mechanisms underlying the development of maladaptive plasticity in patients with chronic pain and the putative mechanisms of NIBS in modulating synaptic plasticity in neuropathic pain conditions. PMID:27512368

  13. Cell-free nucleic acids as a non-invasive route for investigating atherosclerosis.

    PubMed

    Cerne, Darko; Bajalo, Jana Lukac

    2014-01-01

    Metabolic syndrome is directly linked with atherosclerotic burden and cell-free nucleic acids (cf-NA) analysis has recently emerged as a novel research tool in atherosclerosis practice and research. cf-NA are nucleic acids (DNA, mRNA, miRNA, mitochondrial DNA) found in plasma and cell-free fractions of various other biological fluids. They have all the characteristics of the nucleic acids in the cells of their origin, thus constituting an emerging field for non-invasive assessment. Initially, quantitative and qualitative analysis of cf-NA has been accepted as clinically useful in non-invasive prenatal diagnosis, and in the diagnosis and monitoring of numerous cancers. As to atherosclerosis, cf-NA analysis poses an important challenge in diagnosis and prognostic evaluation of acute coronary syndrome, in prediction of cardiovascular disease, in non-invasive early detection of atherosclerosis and understanding its pathological mechanism in vivo, in assessing various issues of treatment for atherosclerosis in vivo, and in the unique simultaneous measurement of mRNA levels and protein concentrations in a single sample of plasma. Examples of its use are presented in this review. Besides the advances in technologies, the precise evaluation and optimization of pre-analytical and analytical aspects of cf-NA analysis have impacted importantly on the reliability of test results. We have, therefore, reviewed the most important analytical considerations. Further clinical studies and analytical improvements will answer the question as to whether cf-NA, as novel biomarkers, can be reliably applied clinically in non-invasive, early diagnosis and monitoring of the vulnerable atherosclerotic plaques of patients who could suffer from acute coronary syndrome. PMID:24320033

  14. Non-invasive Brain Stimulation, a Tool to Revert Maladaptive Plasticity in Neuropathic Pain

    PubMed Central

    Naro, Antonino; Milardi, Demetrio; Russo, Margherita; Terranova, Carmen; Rizzo, Vincenzo; Cacciola, Alberto; Marino, Silvia; Calabro, Rocco S.; Quartarone, Angelo

    2016-01-01

    Neuromodulatory effects of non-invasive brain stimulation (NIBS) have been extensively studied in chronic pain. A hypothetic mechanism of action would be to prevent or revert the ongoing maladaptive plasticity within the pain matrix. In this review, the authors discuss the mechanisms underlying the development of maladaptive plasticity in patients with chronic pain and the putative mechanisms of NIBS in modulating synaptic plasticity in neuropathic pain conditions. PMID:27512368

  15. Diffuse correlation spectroscopy for non-invasive, micro-vascular cerebral blood flow measurement

    PubMed Central

    Durduran, Turgut; Yodh, Arjun G.

    2013-01-01

    Diffuse correlation spectroscopy (DCS) uses the temporal fluctuations of near-infrared (NIR) light to measure cerebral blood flow (CBF) non-invasively. Here, we provide a brief history of DCS applications in brain with an emphasis on the underlying physical ideas, common instrumentation and validation. Then we describe recent clinical research that employs DCS-measured CBF as a biomarker of patient well-being, and as an indicator of hemodynamic and metabolic response to functional stimuli. PMID:23770408

  16. Non-invasive prediction of hemoglobin levels by principal component and back propagation artificial neural network

    PubMed Central

    Ding, Haiquan; Lu, Qipeng; Gao, Hongzhi; Peng, Zhongqi

    2014-01-01

    To facilitate non-invasive diagnosis of anemia, specific equipment was developed, and non-invasive hemoglobin (HB) detection method based on back propagation artificial neural network (BP-ANN) was studied. In this paper, we combined a broadband light source composed of 9 LEDs with grating spectrograph and Si photodiode array, and then developed a high-performance spectrophotometric system. By using this equipment, fingertip spectra of 109 volunteers were measured. In order to deduct the interference of redundant data, principal component analysis (PCA) was applied to reduce the dimensionality of collected spectra. Then the principal components of the spectra were taken as input of BP-ANN model. On this basis we obtained the optimal network structure, in which node numbers of input layer, hidden layer, and output layer was 9, 11, and 1. Calibration and correction sample sets were used for analyzing the accuracy of non-invasive hemoglobin measurement, and prediction sample set was used for testing the adaptability of the model. The correlation coefficient of network model established by this method is 0.94, standard error of calibration, correction, and prediction are 11.29g/L, 11.47g/L, and 11.01g/L respectively. The result proves that there exist good correlations between spectra of three sample sets and actual hemoglobin level, and the model has a good robustness. It is indicated that the developed spectrophotometric system has potential for the non-invasive detection of HB levels with the method of BP-ANN combined with PCA. PMID:24761296

  17. A non-invasive head-holding device for chronic neural recordings in awake behaving monkeys

    PubMed Central

    Amemori, Satoko; Amemori, Ken-ichi; Cantor, Margaret L.; Graybiel, Ann M.

    2014-01-01

    Background We have developed a novel head-holding device for behaving non-human primates that affords stability suitable for reliable chronic electrophysiological recording experiments. The device is completely non-invasive, and thus avoids the risk of infection and other complications that can occur with the use of conventional, surgically implanted head-fixation devices. New method The device consists of a novel non-invasive head mold and bar clamp holder, and is customized to the shape of each monkey’s head. The head-holding device that we introduce, combined with our recording system and reflection-based eye-tracking system, allows for chronic behavioral experiments and single-electrode or multi-electrode recording, as well as manipulation of brain activity. Results and comparison with existing methods With electrodes implanted chronically in multiple brain regions, we could record neural activity from cortical and subcortical structures with stability equal to that recorded with conventional head-post fixation. Consistent with the non-invasive nature of the device, we could record neural signals for more than two years with a single implant. Importantly, the monkeys were able to hold stable eye fixation positions while held by this device, demonstrating the possibility of analyzing eye movement data with only the gentle restraint imposed by the non-invasive head-holding device. Conclusions We show that the head-holding device introduced here can be extended to the head holding of smaller animals, and note that it could readily be adapted for magnetic resonance brain imaging over extended periods of time. PMID:25448381

  18. Non-invasive cortisol measurements as indicators of physiological stress responses in guinea pigs.

    PubMed

    Nemeth, Matthias; Pschernig, Elisabeth; Wallner, Bernard; Millesi, Eva

    2016-01-01

    Non-invasive measurements of glucocorticoid (GC) concentrations, including cortisol and corticosterone, serve as reliable indicators of adrenocortical activities and physiological stress loads in a variety of species. As an alternative to invasive analyses based on plasma, GC concentrations in saliva still represent single-point-of-time measurements, suitable for studying short-term or acute stress responses, whereas fecal GC metabolites (FGMs) reflect overall stress loads and stress responses after a species-specific time frame in the long-term. In our study species, the domestic guinea pig, GC measurements are commonly used to indicate stress responses to different environmental conditions, but the biological relevance of non-invasive measurements is widely unknown. We therefore established an experimental protocol based on the animals' natural stress responses to different environmental conditions and compared GC levels in plasma, saliva, and fecal samples during non-stressful social isolations and stressful two-hour social confrontations with unfamiliar individuals. Plasma and saliva cortisol concentrations were significantly increased directly after the social confrontations, and plasma and saliva cortisol levels were strongly correlated. This demonstrates a high biological relevance of GC measurements in saliva. FGM levels measured 20 h afterwards, representing the reported mean gut passage time based on physiological validations, revealed that the overall stress load was not affected by the confrontations, but also no relations to plasma cortisol levels were detected. We therefore measured FGMs in two-hour intervals for 24 h after another social confrontation and detected significantly increased levels after four to twelve hours, reaching peak concentrations already after six hours. Our findings confirm that non-invasive GC measurements in guinea pigs are highly biologically relevant in indicating physiological stress responses compared to circulating levels

  19. Non-invasive, non-radiological quantification of anteroposterior knee joint ligamentous laxity

    PubMed Central

    Russell, D. F.; Deakin, A. H.; Fogg, Q. A.; Picard, F.

    2013-01-01

    Objectives We performed in vitro validation of a non-invasive skin-mounted system that could allow quantification of anteroposterior (AP) laxity in the outpatient setting. Methods A total of 12 cadaveric lower limbs were tested with a commercial image-free navigation system using trackers secured by bone screws. We then tested a non-invasive fabric-strap system. The lower limb was secured at 10° intervals from 0° to 60° of knee flexion and 100 N of force was applied perpendicular to the tibia. Acceptable coefficient of repeatability (CR) and limits of agreement (LOA) of 3 mm were set based on diagnostic criteria for anterior cruciate ligament (ACL) insufficiency. Results Reliability and precision within the individual invasive and non-invasive systems was acceptable throughout the range of flexion tested (intra-class correlation coefficient 0.88, CR 1.6 mm). Agreement between the two systems was acceptable measuring AP laxity between full extension and 40° knee flexion (LOA 2.9 mm). Beyond 40° of flexion, agreement between the systems was unacceptable (LOA > 3 mm). Conclusions These results indicate that from full knee extension to 40° flexion, non-invasive navigation-based quantification of AP tibial translation is as accurate as the standard validated commercial system, particularly in the clinically and functionally important range of 20° to 30° knee flexion. This could be useful in diagnosis and post-operative evaluation of ACL pathology. Cite this article: Bone Joint Res 2013;2:233–7. PMID:24184443

  20. Non-invasive cortisol measurements as indicators of physiological stress responses in guinea pigs

    PubMed Central

    Pschernig, Elisabeth; Wallner, Bernard; Millesi, Eva

    2016-01-01

    Non-invasive measurements of glucocorticoid (GC) concentrations, including cortisol and corticosterone, serve as reliable indicators of adrenocortical activities and physiological stress loads in a variety of species. As an alternative to invasive analyses based on plasma, GC concentrations in saliva still represent single-point-of-time measurements, suitable for studying short-term or acute stress responses, whereas fecal GC metabolites (FGMs) reflect overall stress loads and stress responses after a species-specific time frame in the long-term. In our study species, the domestic guinea pig, GC measurements are commonly used to indicate stress responses to different environmental conditions, but the biological relevance of non-invasive measurements is widely unknown. We therefore established an experimental protocol based on the animals’ natural stress responses to different environmental conditions and compared GC levels in plasma, saliva, and fecal samples during non-stressful social isolations and stressful two-hour social confrontations with unfamiliar individuals. Plasma and saliva cortisol concentrations were significantly increased directly after the social confrontations, and plasma and saliva cortisol levels were strongly correlated. This demonstrates a high biological relevance of GC measurements in saliva. FGM levels measured 20 h afterwards, representing the reported mean gut passage time based on physiological validations, revealed that the overall stress load was not affected by the confrontations, but also no relations to plasma cortisol levels were detected. We therefore measured FGMs in two-hour intervals for 24 h after another social confrontation and detected significantly increased levels after four to twelve hours, reaching peak concentrations already after six hours. Our findings confirm that non-invasive GC measurements in guinea pigs are highly biologically relevant in indicating physiological stress responses compared to circulating

  1. Sub-millimeter Bunch Length Non-invasive Diagnostic Based on the Diffraction and Cherenkov Radiation

    NASA Astrophysics Data System (ADS)

    Shevelev, M.; Deng, H.; Potylitsyn, A.; Naumenko, G.; Zhang, J.; Lu, Sh; Gogolev, S.; Shkitov, D.

    2012-05-01

    A layout for the investigation the coherent Cherenkov radiation from a dielectric target with a large spectral dispersion and the coherent diffraction radiation from a conducting screen as a tool for non-invasive longitudinal electron beam profile diagnostics are proposed for the 20~30MeV Linac at Shanghai Institute of Applied Physics (SINAP). In this paper the status of the joint experiment and future plans are presented.

  2. Development and validation of a MRgHIFU non-invasive tissue acoustic property estimation technique.

    PubMed

    Johnson, Sara L; Dillon, Christopher; Odéen, Henrik; Parker, Dennis; Christensen, Douglas; Payne, Allison

    2016-11-01

    MR-guided high-intensity focussed ultrasound (MRgHIFU) non-invasive ablative surgeries have advanced into clinical trials for treating many pathologies and cancers. A remaining challenge of these surgeries is accurately planning and monitoring tissue heating in the face of patient-specific and dynamic acoustic properties of tissues. Currently, non-invasive measurements of acoustic properties have not been implemented in MRgHIFU treatment planning and monitoring procedures. This methods-driven study presents a technique using MR temperature imaging (MRTI) during low-temperature HIFU sonications to non-invasively estimate sample-specific acoustic absorption and speed of sound values in tissue-mimicking phantoms. Using measured thermal properties, specific absorption rate (SAR) patterns are calculated from the MRTI data and compared to simulated SAR patterns iteratively generated via the Hybrid Angular Spectrum (HAS) method. Once the error between the simulated and measured patterns is minimised, the estimated acoustic property values are compared to the true phantom values obtained via an independent technique. The estimated values are then used to simulate temperature profiles in the phantoms, and compared to experimental temperature profiles. This study demonstrates that trends in acoustic absorption and speed of sound can be non-invasively estimated with average errors of 21% and 1%, respectively. Additionally, temperature predictions using the estimated properties on average match within 1.2 °C of the experimental peak temperature rises in the phantoms. The positive results achieved in tissue-mimicking phantoms presented in this study indicate that this technique may be extended to in vivo applications, improving HIFU sonication temperature rise predictions and treatment assessment. PMID:27441427

  3. A rapid and non-invasive bio-photonic technique to monitor the quality of onions

    NASA Astrophysics Data System (ADS)

    Ullah, H.; Hussain, F.; Ahmad, E.; Ikram, M.

    2015-08-01

    We present the use of swept source optical coherence tomography and spectral domain optical coherence tomography for imaging the skins and concentric tissue leaves of intact whole onion bulb as well as single leave. The normal and watery scaled (defective) onion's outer leaves and whole bulb have been characterized by cross sectional imaging of internal defects. The method can be used as potential investigating technique for application of food quality check during long storage.

  4. Optical Characterization of Window Materials for Aerospace Applications

    NASA Technical Reports Server (NTRS)

    Tedjojuwono, Ken K.; Clark, Natalie; Humphreys, William M., Jr.

    2013-01-01

    An optical metrology laboratory has been developed to characterize the optical properties of optical window materials to be used for aerospace applications. Several optical measurement systems have been selected and developed to measure spectral transmittance, haze, clarity, birefringence, striae, wavefront quality, and wedge. In addition to silica based glasses, several optical lightweight polymer materials and transparent ceramics have been investigated in the laboratory. The measurement systems and selected empirical results for non-silica materials are described. These measurements will be used to form the basis of acceptance criteria for selection of window materials for future aerospace vehicle and habitat designs.

  5. Comparison of invasive and non-invasive blood pressure monitoring during clinical anaesthesia in dogs.

    PubMed

    MacFarlane, Paul D; Grint, Nicola; Dugdale, Alexandra

    2010-03-01

    Monitoring blood pressure during anaesthesia is widely recommended in man and animals. The accuracy of any device used to measure blood pressure is an important consideration when selecting monitoring equipment, the ANSI/AAMI SP10 standard is widely cited in this respect in recent veterinary publications. Blood pressure was monitored using invasive and non-invasive techniques during clinical anaesthesia in 19 dogs. The results were compared using Bland-Altman analysis. The bias (and limits of agreement) between invasive and non-invasive measurement was 7.1 mmHg (+/-34.7) for systolic blood pressure, -1.8 mmHg (+/-27.4) for mean blood pressure and 6.9 mmHg (+/-27.5) for diastolic blood pressure. In a clinical setting the bias between invasive and non-invasive measurement techniques was similar or smaller than laboratory reports, however the limits of agreement were considerably wider suggesting that care should be exercised when interpreting NIBP values. PMID:20306347

  6. Non-invasive pressure difference estimation from PC-MRI using the work-energy equation

    PubMed Central

    Donati, Fabrizio; Figueroa, C. Alberto; Smith, Nicolas P.; Lamata, Pablo; Nordsletten, David A.

    2015-01-01

    Pressure difference is an accepted clinical biomarker for cardiovascular disease conditions such as aortic coarctation. Currently, measurements of pressure differences in the clinic rely on invasive techniques (catheterization), prompting development of non-invasive estimates based on blood flow. In this work, we propose a non-invasive estimation procedure deriving pressure difference from the work-energy equation for a Newtonian fluid. Spatial and temporal convergence is demonstrated on in silico Phase Contrast Magnetic Resonance Image (PC-MRI) phantoms with steady and transient flow fields. The method is also tested on an image dataset generated in silico from a 3D patient-specific Computational Fluid Dynamics (CFD) simulation and finally evaluated on a cohort of 9 subjects. The performance is compared to existing approaches based on steady and unsteady Bernoulli formulations as well as the pressure Poisson equation. The new technique shows good accuracy, robustness to noise, and robustness to the image segmentation process, illustrating the potential of this approach for non-invasive pressure difference estimation. PMID:26409245

  7. Non-invasive pressure difference estimation from PC-MRI using the work-energy equation.

    PubMed

    Donati, Fabrizio; Figueroa, C Alberto; Smith, Nicolas P; Lamata, Pablo; Nordsletten, David A

    2015-12-01

    Pressure difference is an accepted clinical biomarker for cardiovascular disease conditions such as aortic coarctation. Currently, measurements of pressure differences in the clinic rely on invasive techniques (catheterization), prompting development of non-invasive estimates based on blood flow. In this work, we propose a non-invasive estimation procedure deriving pressure difference from the work-energy equation for a Newtonian fluid. Spatial and temporal convergence is demonstrated on in silico Phase Contrast Magnetic Resonance Image (PC-MRI) phantoms with steady and transient flow fields. The method is also tested on an image dataset generated in silico from a 3D patient-specific Computational Fluid Dynamics (CFD) simulation and finally evaluated on a cohort of 9 subjects. The performance is compared to existing approaches based on steady and unsteady Bernoulli formulations as well as the pressure Poisson equation. The new technique shows good accuracy, robustness to noise, and robustness to the image segmentation process, illustrating the potential of this approach for non-invasive pressure difference estimation. PMID:26409245

  8. From promise to practice: pairing non-invasive sampling with genomics in conservation

    PubMed Central

    Waterhouse, Matthew D.; Etter, Paul D.; Johnson, Eric A.

    2015-01-01

    Conservation genomics has become an increasingly popular term, yet it remains unclear whether the non-invasive sampling that is essential for many conservation-related studies is compatible with the minimum requirements for harnessing next-generation sequencing technologies. Here, we evaluated the feasibility of using genotyping-by-sequencing of non-invasively collected hair samples to simultaneously identify and genotype single nucleotide polymorphisms (SNPs) in a climate-sensitive mammal, the American pika (Ochotona princeps). We identified and genotyped 3,803 high-confidence SNPs across eight sites distributed along two elevational transects using starting DNA amounts as low as 1 ng. Fifty-five outlier loci were detected as candidate gene regions under divergent selection, constituting potential targets for future validation. Genome-wide estimates of gene diversity significantly and positively correlated with elevation across both transects, with all low elevation sites exhibiting significant heterozygote deficit likely due to inbreeding. More broadly, our results highlight a range of issues that must be considered when pairing genomic data collection with non-invasive sampling, particularly related to field sampling protocols for minimizing exogenous DNA, data collection strategies and quality control steps for enhancing target organism yield, and analytical approaches for maximizing cost-effectiveness and information content of recovered genomic data. PMID:26244114

  9. SRY sequence in maternal plasma: Implications for non-invasive prenatal diagnosis: First report from India

    PubMed Central

    D’Souza, Edna; Nair, Sona; Nadkarni, Anita; Ghosh, Kanjaksha; Colah, Roshan B.

    2012-01-01

    AIM: The presence of circulatory cell-free fetal DNA in maternal plasma has found new applications in non-invasive risk-free prenatal diagnosis. MATERIALS AND METHODS: We made use of a size separation approach along with real time polymerase chain reaction (PCR) to evaluate the use of fetal DNA in the detection of the sex of the fetus. Cell-free fetal DNA was isolated from the plasma of 30 women (10–20 weeks gestation) using a size separation approach. We made use of Taq Man Chemistry and real time PCR using primers and probes for GAPDH and SRY. RESULTS: Only 24 cases could be studied as there was no amplification in six cases. Fetal sex was accurately determined in all of the 24 cases wherein 19 women were carrying male fetuses and five women were carrying female fetuses. An increase in the amount of fetal DNA was observed with an increase in the gestational age. CONCLUSIONS: Real time PCR analysis is a highly sensitive and accurate tool for non-invasive prenatal diagnosis, allowing detection of the sex of the fetus as early as 10 weeks of gestation. Non-invasive prenatal diagnosis eliminates the risk of fetal loss associated with the invasive procedure. PMID:22754228

  10. Continuous non-invasive monitoring improves blood pressure stability in upright position: randomized controlled trial.

    PubMed

    Benes, Jan; Simanova, Alena; Tovarnicka, Tereza; Sevcikova, Silvie; Kletecka, Jakub; Zatloukal, Jan; Pradl, Richard; Chytra, Ivan; Kasal, Eduard

    2015-02-01

    Intermittent blood pressure (BP) monitoring is the standard-of-care during low and intermediate risk anaesthesia, yet it could lead to delayed recognition of BP fluctuations. Perioperative hypotension is known to be associated with postoperative complications. Continuous, non-invasive methods for BP monitoring have been developed recently. We have tested a novel non-invasive, continuous monitor (using the volume clamp method) to assist with maintaining BP in safe ranges for patients undergoing surgery in a beach chair position. Forty adult patients undergoing thyroid gland surgery in an upright position were included in this prospective randomised controlled trial. Patients were equally allocated to the group with continuous monitoring of BP using the CNAP® Monitor and to the control group managed using an intermittent oscillometric BP cuff. The absolute and proportional time spent outside the range of ±20% of the target BP along with other hemodynamic and clinical parameters were evaluated. The continuous monitoring decreased the anaesthesia time spent below -20% pressure range [absolute: 12 min (4-20) vs. 27 min (16-34); p=0.001; relative to procedure length: 14% (7-20) vs. 33.5% (17.5-53); p=0.003]. No significant differences were observed in postoperative morbidity or in hospital length of stay. Continuous non-invasive BP monitoring via the CNAP® Monitor allows for better BP management in patients undergoing surgery in a beach chair position. In our randomised trial the time spent in hypotension was significantly shorter using continuous monitoring. PMID:24841333

  11. Non-invasive Markers of Liver Fibrosis: Adjuncts or Alternatives to Liver Biopsy?

    PubMed Central

    Chin, Jun L.; Pavlides, Michael; Moolla, Ahmad; Ryan, John D.

    2016-01-01

    Liver fibrosis reflects sustained liver injury often from multiple, simultaneous factors. Whilst the presence of mild fibrosis on biopsy can be a reassuring finding, the identification of advanced fibrosis is critical to the management of patients with chronic liver disease. This necessity has lead to a reliance on liver biopsy which itself is an imperfect test and poorly accepted by patients. The development of robust tools to non-invasively assess liver fibrosis has dramatically enhanced clinical decision making in patients with chronic liver disease, allowing a rapid and informed judgment of disease stage and prognosis. Should a liver biopsy be required, the appropriateness is clearer and the diagnostic yield is greater with the use of these adjuncts. While a number of non-invasive liver fibrosis markers are now used in routine practice, a steady stream of innovative approaches exists. With improvement in the reliability, reproducibility and feasibility of these markers, their potential role in disease management is increasing. Moreover, their adoption into clinical trials as outcome measures reflects their validity and dynamic nature. This review will summarize and appraise the current and novel non-invasive markers of liver fibrosis, both blood and imaging based, and look at their prospective application in everyday clinical care. PMID:27378924

  12. Assessment of lung function using a non-invasive oscillating gas-forcing technique☆

    PubMed Central

    Clifton, Lei; Clifton, David A.; Hahn, Clive E.W.; Farmery, Andrew D.

    2013-01-01

    Conventional methods for monitoring lung function can require complex, or special, gas analysers, and may therefore not be practical in clinical areas such as the intensive care unit (ICU) or operating theatre. The system proposed in this article is a compact and non-invasive system for the measurement and monitoring of lung variables, such as alveolar volume, airway dead space, and pulmonary blood flow. In contrast with conventional methods, the compact apparatus and non-invasive nature of the proposed method could eventually allow it to be used in the ICU, as well as in general clinical settings. We also propose a novel tidal ventilation model using a non-invasive oscillating gas-forcing technique, where both nitrous oxide and oxygen are used as indicator gases. Experimental results are obtained from healthy volunteers, and are compared with those obtained using a conventional continuous ventilation model. Our findings show that the proposed technique can be used to assess lung function, and has several advantages over conventional methods such as compact and portable apparatus, easy usage, and quick estimation of cardiopulmonary variables. PMID:23702307

  13. Best Ethical Practices for Clinicians and Laboratories in the Provision of Non-Invasive Prenatal Testing

    PubMed Central

    Allyse, MA; Sayres, LC; Havard, M; King, JS; Greely, HT; Hudgins, L; Taylor, J; Norton, ME; Cho, MK; Magnus, D; Ormond, KE

    2014-01-01

    Objective To provide an ethical framework for clinicians and companies providing non-invasive prenatal testing using cell-free fetal DNA or whole fetal cells. Method In collaboration with an NIH-supported research ethics consultation committee, together with feedback from an inter-disciplinary group of clinicians, members of industry, legal experts and genetic counselors we developed a set of best practices for the provision of non-invasive prenatal genetic testing. Results Principal recommendations include the amendment of current informed consent procedures to include attention to the non-invasive nature of new testing and the potential for a broader range of results earlier in the pregnancy. We strongly recommend that tests should only be provided through licensed medical providers and not direct-to-consumer. Conclusion Prenatal tests, including new methods using cell-free fetal DNA, are not currently regulated by government agencies and limited professional guidance is available. In the absence of regulation, companies and clinicians should cooperate to adopt responsible best ethical practices in the provision of these tests. PMID:23613322

  14. A non-invasive method for the determination of liquid injectables by Raman spectroscopy.

    PubMed

    Zhao, Yu; Ji, Nan; Yin, Lihui; Wang, Jun

    2015-08-01

    Drug safety has become a very important subject, and more countries have joined in the fight against counterfeit drugs. This study demonstrated a non-invasive Raman spectroscopy method that could be utilized for screening liquid injectable drugs for spurious/falsely-labeled/falsified/counterfeit medical products (SFFCs). Two problems were solved to remove the blocks in identification and quantitation: one problem was the weak API signal extraction from the non-invasive Raman spectra and the other was the problem of Raman absolute measurement. Principal component analysis (PCA) and classical least square (CLS) algorithms were performed to establish the models. Water was chosen as the "internal standard" to normalize the spectra to solve the problem of Raman absolute measurement. The results showed that the 11 positive samples and 66 negative samples were all well identified with a threshold of 0.95. One of the positive samples contained the excipient propylene glycol, which was identified successfully at the same time. The accuracy of quantitative results was approximately 5% for doxofylline liquid injectables and about 10% for the low-concentration and big glass bottle-containers of Levofloxacin Lactate and Sodium Chloride Injections as compared to the results using an HPLC method, this is satisfactory for fast screening of SFFCs. In conclusion, with the development of a database of identification and quantitation models, this method may determine liquid injectable drugs in a fast and non-invasive way and become one of the most powerful weapons against SFFCs. Graphical Abstract ᅟ. PMID:25588367

  15. [The effect of non-invasive mechanical ventilation in postoperative respiratory failure].

    PubMed

    Ozyılmaz, Ezgi; Kaya, Akın

    2012-01-01

    Postoperative respiratory failure is related with the highest mortality and morbidity among all perioperative complications. The most common underlying mechanism of postoperative respiratory failure is the development of atelectasis. Anaesthesia, medications which cause respiratory depression, high FiO2 use, postoperative pain and disruption of muscle forces due to surgery leads to decrease in functional residual capacity and results in atelectasis formation. Atelectasis causes severe hypoxemia due to ventilation, perfusion mismatch, shunt and increased peripheral vascular resistance. Intrathoracic positive pressure is an effective therapeutic option in both prevention and treatment of atelectasis. Non-invasive mechanical ventilation is related with a lower mortality and morbidity rate due to lack of any potential complication risks of endotracheal intubation. Non-invasive mechanical ventilation can be applied as prophylactic or curative. Both of these techniques are related with lower reintubation rates, nosocomial infections, duration of hospitalization and mortality in patients with postoperative respiratory failure. The differences of this therapy from standard application and potential complications should be well known in order to improve prognosis in these group of patients. The primary aim of this review is to underline the pathogenesis of postoperative respiratory failure. The secondary aim is to clarify the optimum method, effect and complications of non-invasive mechanical ventilation therapy under the light of the studies which was performed in specific patient groups. PMID:22779943

  16. Promoting social plasticity in developmental disorders with non-invasive brain stimulation techniques

    PubMed Central

    Boggio, Paulo S.; Asthana, Manish K.; Costa, Thiago L.; Valasek, Cláudia A.; Osório, Ana A. C.

    2015-01-01

    Being socially connected directly impacts our basic needs and survival. People with deficits in social cognition might exhibit abnormal behaviors and face many challenges in our highly social-dependent world. These challenges and limitations are associated with a substantial economical and subjective impact. As many conditions where social cognition is affected are highly prevalent, more treatments have to be developed. Based on recent research, we review studies where non-invasive neuromodulatory techniques have been used to promote Social Plasticity in developmental disorders. We focused on three populations where non-invasive brain stimulation seems to be a promising approach in inducing social plasticity: Schizophrenia, Autism Spectrum Disorder (ASD) and Williams Syndrome (WS). There are still very few studies directly evaluating the effects of transcranial direct current stimulation (tDCS) and transcranial magnetic stimulation (TMS) in the social cognition of these populations. However, when considering the promising preliminary evidences presented in this review and the limited amount of clinical interventions available for treating social cognition deficits in these populations today, it is clear that the social neuroscientist arsenal may profit from non-invasive brain stimulation techniques for rehabilitation and promotion of social plasticity. PMID:26388712

  17. Non-invasive Diagnosis of Fibrosis in Non-alcoholic Fatty Liver Disease

    PubMed Central

    Arora, Anil; Sharma, Praveen

    2012-01-01

    Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in developed as well as in developing countries. Its prevalence continues to rise currently affecting approximately 20-30% of adults and 10% of children in the United States. Non-alcoholic fatty liver disease represents a wide spectrum of conditions ranging from fatty liver, which in general follows a benign non-progressive clinical course, to non-alcoholic steatohepatitis (NASH), a more serious form of NAFLD that may progress to cirrhosis and end-stage liver disease. Liver biopsy remains the gold standard for evaluating the degree of hepatic necroinflammation and fibrosis; however, several non-invasive investigations, such as serum biomarkers, have been developed to establish the diagnosis and also to evaluate treatment response. There has been a substantial development of non-invasive risk scores, biomarker panels, and radiological modalities to identify at risk patients with NAFLD without recourse to liver biopsy on a routine basis. Examples include combination of serum markers like NAFLD fibrosis score (NFS), BARD score, fibrometer, FIB4, and non-invasive tools like fibroscan which assess fibrosis in patients with NAFLD. Other markers of fibrosis that have been evaluated include high-sensitivity C-reactive protein, plasma pentraxin 3, interleukin-6, and cytokeratin-18. This review focuses on the methods currently available in daily clinical practice in hepatology and touches briefly on the potential future markers under investigation. PMID:25755423

  18. Multi-scale simulations predict responses to non-invasive nerve root stimulation

    NASA Astrophysics Data System (ADS)

    Laakso, Ilkka; Matsumoto, Hideyuki; Hirata, Akimasa; Terao, Yasuo; Hanajima, Ritsuko; Ugawa, Yoshikazu

    2014-10-01

    Objective. Established biophysical neurone models have achieved limited success in reproducing electrophysiological responses to non-invasive stimulation of the human nervous system. This is related to our insufficient knowledge of the induced electric currents inside the human body. Despite the numerous research and clinical applications of non-invasive stimulation, it is still unclear which internal sites are actually affected by it. Approach. We performed multi-scale computer simulations that, by making use of advances in computing power and numerical algorithms, combine a microscopic model of electrical excitation of neurones with a macroscopic electromagnetic model of the realistic whole-body anatomy. Main results. The simulations yield responses consistent with those experimentally recorded following magnetic and electrical motor root stimulation in human subjects, and reproduce the observed amplitudes and latencies for a wide variety of stimulation parameters. Significance. Our findings demonstrate that modern computational techniques can produce detailed predictions about which and where neurones are activated, leading to improved understanding of the physics and basic mechanisms of non-invasive stimulation and enabling potential new applications that make use of improved targeting of stimulation.

  19. Stress detection in bivalve mollusk using non-invasive bioelectric monitoring of myoneural behavior

    SciTech Connect

    Morgan, E.L.; Hardison, B.S.; Dawson, V.K.; Waller, D.; Waller, W.T.; Dickson, K.L.; Allen, H.J.

    1995-12-31

    Few studies have demonstrated cause-and-effect linkages between extrinsic environmental factors and intrinsic bioelectric action potentials of bivalve mollusk using non-invasive, non-destructive approaches. A non-invasive, external probe configuration and detection system, similar to one used previously with native unionids, was developed for continuously monitoring bioelectric activities of clams and mussels. Using remote probes and differential amplifiers, bioelectric activities were recorded for cardiac, adductor, siphon and foot responses using a computer equipped with integrating software. To test if remote, non-invasive probes would detect similar information to that recorded by invasive needle electrodes, two individuals of zebra mussel (Dreissenia polymorpha), and Asiatic clam (Corbicula fluminea) were each configured with two sets of probes. One set was inserted between the valves and along the inside surface of the shelf; the other set was positioned remotely about the outside margins of the valves. Signal validation was made by simultaneously recording bioelectric responses for the same animal from both sets of probes. In preliminary stress tests monitored bivalves were subjected to changes in temperatures over 2 to 3 hr intervals from ambient to potentially lethal levels (20 to 30 C for zebra, 25 C to 40 C for corbicula). Dramatic increases resulted in both number and amplitude of cardiac events as temperature increased. Planned studies will use this approach to evaluate bivalve myoneural behavior patterns in response to chemical and non-chemical stimuli.

  20. Non-drug Non-invasive Treatment in the Management of Low Back Pain

    PubMed Central

    Sahu, RL

    2014-01-01

    Background: Low back pain (LBP) is a major medical problem. World-wide, from 60% to 80% of people will have it during their lifetime and 2-5% will have it at any given time. The disease impacts upon activities of daily living ultimately leading to a loss of functional independence and quality of life. Aim: The main purpose of this study was to assess the results of non-drug non-invasive treatment in the management of LBP. Subjects and Methods: This was prospective study conducted in the Department of Orthopedics in M. M. Medical College, Mullana, Ambala, Haryana, India from June 2005 to June 2010. A total of 251 out-patients of LBP with a mean age of 45 years were studied. They were managed with non-invasive treatment and were followed for 24 months. Results: Objective Lumbar Spine Assessments up to the age of 40 years at 2 years were excellent. At 40-60 years of age, it was good to excellent. Over the age of 60 years, it was good. The back pain functional scale were found very good up to the age of 40 years at 2-year follow-up, good to very good between 40 and 60 years and over the age of 60 years it was good. Conclusions: Non-drug non-invasive interventions can reduce pain and improve function in LBP. PMID:25328793

  1. Non-invasive assessment of liver fibrosis in chronic hepatitis B

    PubMed Central

    Branchi, Federica; Conti, Clara Benedetta; Baccarin, Alessandra; Lampertico, Pietro; Conte, Dario; Fraquelli, Mirella

    2014-01-01

    The goal of this review is to provide a comprehensive picture of the role, clinical applications and future perspectives of the most widely used non-invasive techniques for the evaluation of hepatitis B virus (HBV) infection. During the past decade many non-invasive methods have been developed to reduce the need for liver biopsy in staging fibrosis and to overcome whenever possible its limitations, mainly: invasiveness, costs, low reproducibility, poor acceptance by patients. Elastographic techniques conceived to assess liver stiffness, in particular transient elastography, and the most commonly used biological markers will be assessed against their respective role and limitations in staging hepatic fibrosis. Recent evidence highlights that both liver stiffness and some bio-chemical markers correlate with survival and major clinical end-points such as liver decompensation, development of hepatocellular carcinoma and portal hypertension. Thus the non-invasive techniques here discussed can play a major role in the management of patients with chronic HBV-related hepatitis. Given their prognostic value, transient elastography and some bio-chemical markers can be used to better categorize patients with advanced fibrosis and cirrhosis and assign them to different classes of risk for clinically relevant outcomes. Very recent data indicates that the combined measurements of liver and spleen stiffness enable the reliable prediction of portal hypertension and esophageal varices development. PMID:25356021

  2. Non-invasive measurement of choroidal volume change and ocular rigidity through automated segmentation of high-speed OCT imaging

    PubMed Central

    Beaton, L.; Mazzaferri, J.; Lalonde, F.; Hidalgo-Aguirre, M.; Descovich, D.; Lesk, M. R.; Costantino, S.

    2015-01-01

    We have developed a novel optical approach to determine pulsatile ocular volume changes using automated segmentation of the choroid, which, together with Dynamic Contour Tonometry (DCT) measurements of intraocular pressure (IOP), allows estimation of the ocular rigidity (OR) coefficient. Spectral Domain Optical Coherence Tomography (OCT) videos were acquired with Enhanced Depth Imaging (EDI) at 7Hz during ~50 seconds at the fundus. A novel segmentation algorithm based on graph search with an edge-probability weighting scheme was developed to measure choroidal thickness (CT) at each frame. Global ocular volume fluctuations were derived from frame-to-frame CT variations using an approximate eye model. Immediately after imaging, IOP and ocular pulse amplitude (OPA) were measured using DCT. OR was calculated from these peak pressure and volume changes. Our automated segmentation algorithm provides the first non-invasive method for determining ocular volume change due to pulsatile choroidal filling, and the estimation of the OR constant. Future applications of this method offer an important avenue to understanding the biomechanical basis of ocular pathophysiology. PMID:26137373

  3. Orbital Debris Characterization via Laboratory Optical Measurements

    NASA Technical Reports Server (NTRS)

    Cowardin, Healther

    2011-01-01

    Optical observations of orbital debris offer insights that differ from radar measurements (specifically the size parameter,wavelength regime,and altitude range). For example, time-dependent photometric data yield lightcurves in multiple bandpasses that aid in material identification and possible periodic orientations. These data can also be used to help identify shapes and optical properties at multiple phase angles. Capitalizing on optical data products and applying them to generate a more complete understanding of orbital objects is a key objective of NASA's Optical Measurement Program, and the primary reason for the creation of the Optical Measurements Center(OMC). The OMC attempts to emulate space-based illumination conditions using equipment and techniques that parallel telescopic observations and source-target-sensor orientations.

  4. Characterization of Fiber Optic CMM Probe System

    SciTech Connect

    K.W.Swallow

    2007-05-15

    This report documents a study completed on the fiber optic probe system that is a part of the Werth optical CMM. This study was necessary due to a lack of documentation from the vendor for the proper use and calibration of the fiber probe, and was performed in support of the Lithographie Galvanoformung Abformung (LIGA) development program at the FM&T. As a result of this study, a better understanding of the fiber optic probe has been developed, including guidelines for its proper use and calibration.

  5. A visibility characterization program for optical communications through the atmosphere

    NASA Technical Reports Server (NTRS)

    Cowles, K.

    1989-01-01

    A program is described for characterizing the atmosphere as it affects optical communications from a spacecraft. Cloud cover patterns and optical transmission will be determined by setting up three automated observatories in the Southwestern United States. Methods of site selection and operation of hardware and software components are presented, as well as plans for term deployment.

  6. Optical coherence tomography examination of hair

    NASA Astrophysics Data System (ADS)

    Gong, Wei; Huang, Zheng; Xu, Jianshu; Yang, Hongqin; Li, Hui; Xie, Shusen

    2014-09-01

    Human hair is a keratinous tissue composed mostly of flexible keratin, which can form a complex architecture consisting of distinct compartments or units (e.g. hair bulb, inner root sheath, shaft). Variations in hair shaft morphology can reflect ethnical diversity, but may also indicate internal diseases, nutritional deficiency, or hair and scalp disorders. Hair shaft abnormalities in cross section and diameter, as well as ultramorphological characterization and follicle shapes, might be visualized non-invasively by high-speed 2D and 3D optical coherence tomography (OCT). In this study, swept source OCT (ThorLabs) was used to examine human hair. Preliminary results showed that the high-speed OCT was a suitable and promising tool for non-invasive analysis of hair conditions.

  7. Interferometric characterization of joint optical tables

    NASA Astrophysics Data System (ADS)

    Corzo-Garcia, S. C.; Medina-Lopez, R. J.; Anderson, S.; Carriles, R.; Ruiz-Marquez, A.; Castro-Camus, E.

    2011-08-01

    We present a straight forward and practical method for joining pneumatically floated optical tables with no previous preparation. In order to demonstrate this method we joined two optical tables in an uncentered "T-shape" using twenty four stainless steel plates (SSP), and used a Michelson interferometer to compare the stability of the entire "T"-structure versus one of its parts alone, finding that they both show similar rigidity. We also evaluated the performance of two different master-salve leg configurations by calculating the stress on the joint and confirmed the calculations by Michelson interferometry. In terms of floor vibration damping, it was observed that the performance of the system for the joined "T"-table seemed to be comparable to that of a single segment. This method can significantly reduce costs of large optical tables and will be useful to extend existing optical tables without manufacturer modification.

  8. Non-Invasive In Vivo Imaging and Quantification of Tumor Growth and Metastasis in Rats Using Cells Expressing Far-Red Fluorescence Protein.

    PubMed

    Christensen, Jon; Vonwil, Daniel; Shastri, V Prasad

    2015-01-01

    Non-invasive in vivo imaging is emerging as an important tool for basic and preclinical research. Near-infrared (NIR) fluorescence dyes and probes have been used for non-invasive optical imaging since in the NIR region absorption and auto fluorescence by body tissue is low, thus permitting for greater penetration depths and high signal to noise ratio. Currently, cell tracking systems rely on labeling cells prior to injection or administering probes targeting the cell population of choice right before imaging. These approaches do not enable imaging of tumor growth, as the cell label is diluted during cell division. In this study we have developed cell lines stably expressing the far-red fluorescence protein E2-Crimson, thus enabling continuous detection and quantification of tumor growth. In a xenograft rat model, we show that E2-Crimson expressing cells can be detected over a 5 week period using optical imaging. Fluorescence intensities correlated with tumor volume and weight and allowed for a reliable and robust quantification of the entire tumor compartment. Using a novel injection regime, the seeding of MDA-MB-231 breast cancer cells in the lungs in a rat model was established and verified. PMID:26186005

  9. Newly developed photon-cell interactive Monte Carlo (pciMC) simulation for non-invasive and continuous diagnosis of blood during extracorporeal circulation support

    NASA Astrophysics Data System (ADS)

    Sakota, Daisuke; Takatani, Setsuo

    2011-07-01

    We have sought for non-invasive diagnosis of blood during the extracorporeal circulation support. To achieve the goal, we have newly developed a photon-cell interactive Monte Carlo (pciMC) model for optical propagation through blood. The pciMC actually describes the interaction of photons with 3-dimentional biconcave RBCs. The scattering is described by micro-scopical RBC boundary condition based on geometric optics. By using pciMC, we modeled the RBCs inside the extracorporeal circuit will be oriented by the blood flow. The RBCs' orientation was defined as their long axis being directed to the center of the circulation tube. Simultaneously the RBCs were allowed to randomly rotate about the long axis direction. As a result, as flow rate increased, the orientation rate increased and converged to approximately 22% at 0.5 L/min flow rate and above. And finally, by using this model, the pciMC non-invasively and absolutely predicted Hct and hemoglobin with the accuracies of 0.84+/-0.82 [HCT%] and 0.42+/-0.28 [g/dL] respectively against measurements by a blood gas analyzer.

  10. Fiber probes based optical techniques for biomedical diagnosis

    NASA Astrophysics Data System (ADS)

    Arce-Diego, José L.; Fanjul-Vélez, Félix

    2007-06-01

    Although fiber optics have been applied in optical communication and sensor systems for several years in a very successful way, their first application was developed in medicine in the early 20's. Manufacturing and developing of optical fibers for biomedical purposes have required a lot of research efforts in order to achieve a non-invasive, in-vivo, and real-time diagnosis of different diseases in human or animal tissues. In general, optical fiber probes are designed as a function of the optical measurement technique. In this work, a brief description of the main optical techniques for optical characterization of biological tissues is presented. The recent advances in optical fiber probes for biomedical diagnosis in clinical analysis and optical biopsy in relation with the different spectroscopic or tomographic optical techniques are described.

  11. Highly automated optical characterization with FTIR spectrometry

    NASA Technical Reports Server (NTRS)

    Perry, G. L. E.; Szofran, F. R.

    1989-01-01

    The procedure for evaluating the characteristics of II-VI semiconducting infrared sensor materials with a Fourier Transform Infrared (FTIR) spectrometer system will be discussed. While the method of mapping optical characteristics with a spectrometer has been employed previously, this system is highly automated compared to other systems where the optical transmission data are obtained using a FTIR system with a small stationary aperture in the optical path and moving the specimen behind the aperture. The hardware and software, including an algorithm developed for extracting cut-on wavelengths of spectra, as well as several example results, are described to illustrate the advanced level of the system. Additionally, data from transverse slices and longitudinal wafers of the aforementioned semiconductors will be used to show the accuracy of the system in predicting trends in materials such as shapes of growth interfaces and compositional uniformity.

  12. Optical characterization of photolithographic metal grids

    NASA Astrophysics Data System (ADS)

    Osmer, Kurt A.; Jones, Mike I.

    1991-10-01

    Infrared window materials for modern military aircraft must simultaneously provide adequate optical performance and maintain stringent shielding levels for electromagnetic interference (EMI). Microscopic metal grids deposited on the surface of dielectric windows can provide the conductivity necessary for proper radio frequency or RF shielding. This paper will examine the optical impact of three grid patterns designed for EMI suppression. Transmission blockage and beam diffraction in the far-field have been measured and compared to predicted values. A discussion of durability under severe thermal and rain erosion environments is also included.

  13. Optical characterization in wide spectral range by a coherent spectrophotometer

    NASA Astrophysics Data System (ADS)

    Sirutkaitis, Valdas; Eckardt, Robert C.; Balachninaite, Ona; Grigonis, Rimantas; Melninkaitis, A.; Rakickas, T.

    2003-11-01

    We report on the development and use of coherent spectrophotometers specialized for the unusual requirements of characterizing nonlinear optical materials and multilayer dielectric coatings used in laser systems. A large dynamic range is required to measure the linear properties of transmission, reflection and absorption and nonlinear properties of laser-induced damage threshold and nonlinear frequency conversion. Optical parametric oscillators generate coherent radiation that is widely tunable with instantaneous powers that can range from milliwatts to megawatts and are well matched to this application. As particular example a laser spectrophotometer based on optical parametric oscillators and a diode-pumped, Q-switched Nd:YAG laser and suitable for optical characterization in the spectral range 420-4500 nm is described. Measurements include reflectance and transmittance, absorption, scattering and laser-induced damage thresholds. Possibilities of a system based on a 130-fs Ti:sapphire laser and optical parametric generators are also discussed.

  14. Nonlinear nanoprobes for characterizing ultrafast optical near field

    NASA Astrophysics Data System (ADS)

    Li, Haifeng

    With the rapid development of ultrafast optics and nanophotonics, it is crucial to measure the spatiotemporal evolution of an ultrafast optical near field in nanometer spatial and femtosecond temporal resolution with minimal perturbation. Although near-field scanning optical microscopy (NSOM) can achieve nanoscale spatial resolution and various ultrashort pulse diagnostic tools can characterize femtosecond laser pulses, yet such capability to noninvasively characterize the nanoscale characteristics of femtosecond pulses in all three spatial dimensions remains elusive. In this dissertation, we developed different types of nonlinear optical probes to characterize ultrashort optical pulses. The nonlinear optical probe is composed of three parts, a silica fiber taper, a single nanowire bonded to the end of the fiber and nonlinear nanoparticles attached on the tip of the nanowire. The optical fiber taper can be readily mounted on a mechanical stage and served as a macroscopic interface for handling and positioning control. The single nanowire bridges the dimension gap between the nanocrystals and the fiber taper, and is critical for achieving large aspect ratio and hence minimizing optical scattering and perturbation. The nonlinear nanoparticles give rise to its capability to characterize ultrashort optical pulses. The unique fusion of nanoscale and nonlinear features in developed nonlinear optical probes provides the ability of probing ultrafast optical field in complex 3D microand nano- structures. The demonstration of such ability is crucial for understanding the interaction of ultrafast optical fields and nanoscale systems. The fabrication processes of the nonlinear optical probes are illustrated in detail and the optical properties of the probes are investigated. Two different types of nonlinear optical probes, two-photon fluorescent nanoprobes and Second HARmonic nanoProbes (SHARP), are fabricated. Interferometric autocorrelation measurements near the focal point

  15. New trends in imaging spectroscopy: the non-invasive study of the Scrovegni Chapel stained glass windows

    NASA Astrophysics Data System (ADS)

    Rebollo, E.; Ratti, F.; Cortelazzo, G. M.; Poletto, L.; Bertoncello, R.

    2011-06-01

    Imaging spectroscopy (IS) extends the measurement of one-dimensional UV-VIS-NIR spectroscopy to two-dimensional domain providing material characterization and localization. The technique is gaining importance for the study of cultural heritage but its application is mainly focused on the analysis of pigments in paintings. An IS device has been developed and then applied to the study of chromophores in glassy objects. It consists of a visible imaging spectrograph, mounted on a rotation stage, which captures monochromatic images of the sample within a wavelength range from 420 nm to 850 nm. The system has been used for the characterization and mapping of chromophores of hundreds of coloured glass tesserae of the stained glass windows from the Scrovegni Chapel (Padua, Italy). Two measurement methodologies have been performed: transmission and double-transmission modes. In the first case, lamps used to illuminate the sample and the spectrograph are placed on the opposite side of the window, to acquire directly the signal transmitted from the glass. In the latter case, the lamps and the spectrograph are placed on the same side of the window, that is placed on a white scattering screen. The acquired signal comes from the light of the lamps transmitted through the glass, then diffused back by the opaque white screen and finally transmitted again through the glass. Results are discussed comparing both modalities in terms of signal-to-noise ratio and spectral contrast. Visible spectra acquired allow the clear identification of several chromophores, e.g. Co(II), Cr(III) or Mn(III). The IS device acquires numerous spectra in relatively short time in a non-invasive way. According to the authors knowledge, this is the first time in which visible imaging spectroscopy technique has been applied for the study of stained glass windows. As the results show, it could represent a powerful and innovative tool to map chromophores of this kind of artefact, particularly when integrated

  16. Non-invasive method for selection of electrodes and stimulus parameters for FES applications with intrafascicular arrays

    NASA Astrophysics Data System (ADS)

    Dowden, B. R.; Frankel, M. A.; Normann, R. A.; Clark, G. A.

    2012-02-01

    High-channel-count intrafascicular electrode arrays provide comprehensive and selective access to the peripheral nervous system. One practical difficulty in using several electrode arrays to evoke coordinated movements in paralyzed limbs is the identification of the appropriate stimulation channels and stimulus parameters to evoke desired movements. Here we present the use of a six degree-of-freedom load cell placed under the foot of a feline to characterize the muscle activation produced by three 100-electrode Utah Slanted Electrode Arrays (USEAs) implanted into the femoral nerves, sciatic nerves, and muscular branches of the sciatic nerves of three cats. Intramuscular stimulation was used to identify the endpoint force directions produced by 15 muscles of the hind limb, and these directions were used to classify the forces produced by each intrafascicular USEA electrode as flexion or extension. For 451 USEA electrodes, stimulus intensities for threshold and saturation muscle forces were identified, and the 3D direction and linearity of the force recruitment curves were determined. Further, motor unit excitation independence for 198 electrode pairs was measured using the refractory technique. This study demonstrates the utility of 3D endpoint force monitoring as a simple and non-invasive metric for characterizing the muscle-activation properties of hundreds of implanted peripheral nerve electrodes, allowing for electrode and parameter selection for neuroprosthetic applications.

  17. Ancient and historic steel in Japan, India and Europe, a non-invasive comparative study using thermal neutron diffraction.

    PubMed

    Grazzi, F; Civita, F; Williams, A; Scherillo, A; Barzagli, E; Bartoli, L; Edge, D; Zoppi, M

    2011-05-01

    The production and refinement of steel has followed very different paths in different parts of the Eurasian continent. In aiming to characterize the similarities and differences between various smelting and smithing methods, we have analysed steel samples from four different areas and historic periods: the Kotō Age in Japan (twelfth-sixteenth century), the Moghul Empire in India (seventeenth-nineteenth century), the Ottoman Turkish Empire (seventeenth century) and the late Middle Ages (fifteenth century) in Italy. The best quality steel was employed for forging arms and armour of high quality, so that we have selected samples from Japan, India, the Middle East and Italy belonging to such a category. Traditional methods, such as metallography, used to characterize different steels in terms of their carbon contents, microconstituents and slag inclusions, entailed an invasive approach. Since many of the selected artefacts are in a very good state of conservation, a different and non-invasive approach was desirable. To this aim, we have used time of flight neutron diffraction on the Italian Neutron Experimental Station diffractometer, located at the pulsed neutron source ISIS in the United Kingdom. By this technique, we were able to quantify the phase distribution of the metal phases, the slag inclusion content, and the oxidation state of the samples, both as average concentration on the whole artefact and in selected gauge volumes. The results of the present investigation offer an interesting picture of the steel metallurgy in different areas of the world. PMID:21400072

  18. Time-domain optical mammography Softscan: initial results on detection and characterization of breast tumors

    NASA Astrophysics Data System (ADS)

    Intes, Xavier; Djeziri, Salim; Ichalalene, Zahia; Mincu, Niculae; Wang, Yong; St.-Jean, Philippe; Lesage, Frédéric; Hall, David; Boas, David A.; Polyzos, Margaret

    2004-10-01

    Near-infrared (NIR) technology appears promising as a non-invasive clinical technique for breast cancer screening and diagnosis. The technology capitalizes on the relative transparency of human tissue in this spectral range and its sensitivity to the main components of the breast:; water, lipid and hemoglobin. In this work we present initial results obtained using the SoftScan® breast-imaging system developed by ART, Advanced Research Technologies inc., Montreal. This platform consists of a 4-wavelength time-resolved scanning system used to quantify non-invasively the local functional state of breast tissue. The different aspects of the system used to retrieve 3D optical contrast will be presented. Furthermore, preliminary data obtained from a prospective study conducted at The Royal Victoria Hospital of the McGill University Health Center in Montreal will be discussed. Analysis of the data gathered by SoftScan® demonstrated the potential of the technology in discriminating between healthy and diseased tissue.

  19. Development of a versatile enzyme immunoassay for non-invasive assessment of glucocorticoid metabolites in a diversity of taxonomic species.

    PubMed

    Watson, Rebecca; Munro, Coralie; Edwards, Katie L; Norton, Vicki; Brown, Janine L; Walker, Susan L

    2013-06-01

    Endocrinology is a useful tool for conservation biologists and animal managers, and measuring glucocorticoids can help understand biological mechanisms associated with species decline and animal welfare. The current study describes the development and optimization of a glucocorticoid enzyme immunoassay (EIA) to non-invasively assess adrenal activity in a variety of taxa. The antiserum (CJM006) was raised in rabbits to a corticosterone-3-CMO-BSA immunogen and used in a standard competitive EIA system. However, the EIA initially produced results with unacceptably high inter-assay variation, attributed to consistent patterns observed within the optical density of developing plates. To determine the cause of this variability, a number of factors were examined using synthetic corticosterone standard and endogenous faecal extract, including: plate type (Nunc MaxiSorp® II versus Immulon IB plates); the use of non-specific secondary antibody; type (artificial versus natural) and presence (light versus dark) of light during incubation; plate loading temperature (4°C versus room temperature); and substrate reagent temperature (4°C versus room temperature). Results indicated that variability was associated with plate location effects, which were not initially detected because control samples were always run in the same positions across plates. Light and temperature were the two major factors that affected EIA reliability. For this assay, the standard protocol required slight modification, with the optimal protocol using Nunc MaxiSorp® plates, room temperature substrate reagents and dark incubation conditions. Following optimization, this EIA was then validated biochemically for 38 species, through parallel displacement curves and interference assessment tests of faecal and urine samples. Additionally, biological validation was performed opportunistically in a subset of species, with use of this EIA demonstrating significant elevations in faecal glucocorticoid metabolites

  20. Picosecond acoustics in vegetal cells: non-invasive in vitro measurements at a sub-cell scale.

    PubMed

    Audoin, B; Rossignol, C; Chigarev, N; Ducousso, M; Forget, G; Guillemot, F; Durrieu, M C

    2010-02-01

    A 100 fs laser pulse passes through a single transparent cell and is absorbed at the surface of a metallic substrate. Picosecond acoustic waves are generated and propagate through the cell in contact with the metal. Interaction of the high frequency acoustic pulse with a probe laser light gives rise to Brillouin oscillations. The measurements are thus made with lasers for both the opto-acoustic generation and the acousto-optic detection, and acoustic frequencies as high as 11 GHz can be detected, as reported in this paper. The technique offers perspectives for single cell imaging. The in-plane resolution is limited by the pump and probe spot sizes, i.e. approximately 1 microm, and the in-depth resolution is provided by the acoustic frequencies, typically in the GHz range. The effect of the technique on cell safety is discussed. Experiments achieved in vegetal cells illustrate the reproducibility and sensitivity of the measurements. The acoustic responses of cell organelles are significantly different. The results support the potentialities of the hypersonic non-invasive technique in the fields of bio-engineering and medicine. PMID:19879618

  1. A diagnostic study on folium and orchil dyes with non-invasive and micro-destructive methods

    NASA Astrophysics Data System (ADS)

    Aceto, Maurizio; Arrais, Aldo; Marsano, Francesco; Agostino, Angelo; Fenoglio, Gaia; Idone, Ambra; Gulmini, Monica

    2015-05-01

    Folium and orchil are dyes of vegetal origin. Folium is obtained from Chrozophora tinctoria (L.) A. Juss., whereas orchil is obtained from Roccella and other genera of lichens. These dyes were used in the past to impart purple hue to paintings and textiles as substitutes for the more prised Tyrian purple dye, obtained from shellfish. Despite several citations in ancient technical treatises dating back at least to the Greek-Roman age, the identification of these dyes in artworks is rare. In the case of folium, an additional drawback is that its composition is presently unknown. In this work different non-invasive (FT-IR, FT-Raman, fibre optic reflectance spectrophotometry, spectrofluorimetry, X-ray fluorescence spectrometry) and micro-invasive (surface enhanced Raman spectroscopy, matrix assisted laser desorption ionisation-time of flight-mass spectrometry, inductively coupled plasma-mass spectrometry) techniques were used in order to increase the diagnostic information available on these dyes. Measurements were carried out on the dyes extracted from raw materials and on painted or dyed parchments. The possibility to distinguish between folium and orchil by chemical analysis is discussed.

  2. Non-invasive Imaging of the Innate Immune Response in a Zebrafish Larval Model of Streptococcus iniae Infection

    PubMed Central

    Harvie, Elizabeth A.; Huttenlocher, Anna

    2015-01-01

    The aquatic pathogen, Streptococcus iniae, is responsible for over 100 million dollars in annual losses for the aquaculture industry and is capable of causing systemic disease in both fish and humans. A better understanding of S. iniae disease pathogenesis requires an appropriate model system. The genetic tractability and the optical transparency of the early developmental stages of zebrafish allow for the generation and non-invasive imaging of transgenic lines with fluorescently tagged immune cells. The adaptive immune system is not fully functional until several weeks post fertilization, but zebrafish larvae have a conserved vertebrate innate immune system with both neutrophils and macrophages. Thus, the generation of a larval infection model allows the study of the specific contribution of innate immunity in controlling S. iniae infection. The site of microinjection will determine whether an infection is systemic or initially localized. Here, we present our protocols for otic vesicle injection of zebrafish aged 2-3 days post fertilization as well as our techniques for fluorescent confocal imaging of infection. A localized infection site allows observation of initial microbe invasion, recruitment of host cells and dissemination of infection. Our findings using the zebrafish larval model of S. iniae infection indicate that zebrafish can be used to examine the differing contributions of host neutrophils and macrophages in localized bacterial infections. In addition, we describe how photolabeling of immune cells can be used to track individual host cell fate during the course of infection. PMID:25938624

  3. A diagnostic study on folium and orchil dyes with non-invasive and micro-destructive methods.

    PubMed

    Aceto, Maurizio; Arrais, Aldo; Marsano, Francesco; Agostino, Angelo; Fenoglio, Gaia; Idone, Ambra; Gulmini, Monica

    2015-05-01

    Folium and orchil are dyes of vegetal origin. Folium is obtained from Chrozophora tinctoria (L.) A. Juss., whereas orchil is obtained from Roccella and other genera of lichens. These dyes were used in the past to impart purple hue to paintings and textiles as substitutes for the more prised Tyrian purple dye, obtained from shellfish. Despite several citations in ancient technical treatises dating back at least to the Greek-Roman age, the identification of these dyes in artworks is rare. In the case of folium, an additional drawback is that its composition is presently unknown. In this work different non-invasive (FT-IR, FT-Raman, fibre optic reflectance spectrophotometry, spectrofluorimetry, X-ray fluorescence spectrometry) and micro-invasive (surface enhanced Raman spectroscopy, matrix assisted laser desorption ionisation-time of flight-mass spectrometry, inductively coupled plasma-mass spectrometry) techniques were used in order to increase the diagnostic information available on these dyes. Measurements were carried out on the dyes extracted from raw materials and on painted or dyed parchments. The possibility to distinguish between folium and orchil by chemical analysis is discussed. PMID:25703360

  4. Near-infrared quantum-dot-based non-invasive in vivo imaging of squamous cell carcinoma U14

    NASA Astrophysics Data System (ADS)

    Cao, Yu'an; Yang, Kai; Li, Zhigang; Zhao, Cheng; Shi, Chunmeng; Yang, Jia

    2010-11-01

    Near-infrared (near-ir) quantum dots (QDs) are well known for their excellent optical characteristics. They hold great potential for applications in non-invasive long term observation and tracing of cells in vivo. Here, near-ir QDs with an emission wavelength of 800 nm (QD800) were used to label squamous cell carcinoma cell line U14 (U14/QD800). The effect of tissue depth and animal fur on the imaging sensitivity and stability was evaluated following subcutaneous and intramuscular injection into Kunming mice, employing an in vivo imaging system. We have demonstrated that QD800-based visual in vivo imaging increased the sensitivity of cancer early detection by a factor of 100 compared with traditional detection methods. More importantly, this study proved for the first time that animal fur has a serious impact on the detection sensitivity and duration of QD-based in vivo imaging. In general, the duration and sensitivity of QD800 for in vivo imaging were not greatly affected by a depth less than 1.8 ± 0.21 mm (subcutaneous or intramuscular). This study provides critical reference data for further research on near-ir QD-based early detection and in vivo visual observation of cancer.

  5. A non-invasive diffuse reflectance calibration-free method for absolute determination of exogenous biochemicals concentration in biological tissues

    NASA Astrophysics Data System (ADS)

    Lappa, Alexander V.; Kulikovskiy, Artem N.; Busarov, Oleg G.

    2014-03-01

    The paper presents a new method for distant non-destructive determination of concentration of light absorbing admixtures in turbid media. In particular, it is intended for non-invasive in vivo control of accumulation in patient tissues of various biochemicals introduced to the patients for chemotherapy, photodynamic therapy or diagnostics. It is require that the admixture absorption spectrum should have a clearly marked peak in the wavelength region where the pure medium one varies regularly. Fluorescence of admixtures is not required. The method uses the local diffuse reflectance spectroscopy with optical fiber probe including one emitting and two reading There are several features in the method: the value to be determined is absolute concentration of admixtures; the method needs no calibration measurements on phantoms; it needs no reference measurements on sample with zero admixture concentration; it uses a two parametric kinetic light propagation model and original algorithms to resolve direct and inverse tasks of radiation transport theory. Experimental testing passed with tissue equivalent phantoms and different admixtures, including a chlorine photosensitizer, showed accuracy under 10% in all cases.

  6. Optical Characterization of Commercial Lithiated Graphite Battery Electrodes and in Situ Fiber Optic Evanescent Wave Spectroscopy.

    PubMed

    Ghannoum, AbdulRahman; Norris, Ryan C; Iyer, Krishna; Zdravkova, Liliana; Yu, Aiping; Nieva, Patricia

    2016-07-27

    Optical characterization of graphite anodes in lithium ion batteries (LIB) is presented here for potential use in estimating their state of charge (SOC). The characterization is based on reflectance spectroscopy of the anode of commercial LIB cells and in situ optical measurements using an embedded optical fiber sensor. The optical characterization of the anode using wavelengths ranging from 500 to 900 nm supports the dominance of graphite over the solid electrolyte interface in governing the anode's reflectance properties. It is demonstrated that lithiated graphite's reflectance has a significant change in the near-infrared band, 750-900 nm, compared with the visible spectrum as a function of SOC. An embedded optical sensor is used to measure the transmittance of graphite anode in the near-infrared band, and the results suggest that a unique inexpensive method may be developed to estimate the SOC of a LIB. PMID:27379859

  7. Health technology assessment of non-invasive interventions for weight loss and body shape in Iran

    PubMed Central

    Nojomi, Marzieh; Moradi-Lakeh, Maziar; Velayati, Ashraf; Naghibzadeh-Tahami, Ahmad; Dadgostar, Haleh; Ghorabi, Gholamhossein; Moradi-Joo, Mohammad; Yaghoubi, Mohsen

    2016-01-01

    Background: The burden of obesity and diet-related chronic diseases is increasing in Iran, and prevention and treatment strategies are needed to address this problem. The aim of this study was to determine the outcome, cost, safety and cost-consequence of non-invasive weight loss interventions in Iran. Methods: We performed a systematic review to compare non-invasive interventions (cryolipolysis and radiofrequency/ ultrasonic cavitation) with semi-invasive (lipolysis) and invasive (liposuction). A sensitive electronic searching was done to find available interventional studies. Reduction of abdomen circumference (cm), reduction in fat layer thickness (%) and weight reduction (kg) were outcomes of efficacy. Meta-analysis with random models was used for pooling efficacy estimates among studies with the same follow-up duration. Average cost per intervention was estimated based on the capital, maintenance, staff, consumable and purchase costs. Results: Of 3,111 studies identified in our reviews, 13 studies assessed lipolysis, 10 cryolipolysis and 8 considered radiofrequency. Nine studies with the same follow-up duration in three different outcome group were included in meta-analysis. Radiofrequency showed an overall pooled estimate of 2.7 cm (95% CI; 2.3-3.1) of mean reduction in circumference of abdomen after intervention. Pooled estimate of reduction in fat layer thickness was 78% (95% CI; 73%-83%) after Lipolysis and a pooled estimate of weight loss was 3.01 kg (95% CI; 2.3-3.6) after lipousuction. The cost analysis revealed no significant differences between the costs of these interventions. Conclusion: The present study showed that non-invasive interventions appear to have better clinical efficacy, specifically in the body shape measurement, and less cost compared to invasive intervention (liposuction) PMID:27390717

  8. Non-invasive assessment of leaf water status using a dual-mode microwave resonator.

    PubMed

    Dadshani, Said; Kurakin, Andriy; Amanov, Shukhrat; Hein, Benedikt; Rongen, Heinz; Cranstone, Steve; Blievernicht, Ulrich; Menzel, Elmar; Léon, Jens; Klein, Norbert; Ballvora, Agim

    2015-01-01

    The water status in plant leaves is a good indicator for the water status in the whole plant revealing stress if the water supply is reduced. The analysis of dynamic aspects of water availability in plant tissues provides useful information for the understanding of the mechanistic basis of drought stress tolerance, which may lead to improved plant breeding and management practices. The determination of the water content in plant tissues during plant development has been a challenge and is currently feasible based on destructive analysis only. We present here the application of a non-invasive quantitative method to determine the volumetric water content of leaves and the ionic conductivity of the leaf juice from non-invasive microwave measurements at two different frequencies by one sensor device. A semi-open microwave cavity loaded with a ceramic dielectric resonator and a metallic lumped-element capacitor- and inductor structure was employed for non-invasive microwave measurements at 150 MHz and 2.4 Gigahertz on potato, maize, canola and wheat leaves. Three leaves detached from each plant were chosen, representing three developmental stages being representative for tissue of various age. Clear correlations between the leaf- induced resonance frequency shifts and changes of the inverse resonator quality factor at 2.4 GHz to the gravimetrically determined drying status of the leaves were found. Moreover, the ionic conductivity of Maize leaves, as determined from the ratio of the inverse quality factor and frequency shift at 150 MHz by use of cavity perturbation theory, was found to be in good agreement with direct measurements on plant juice. In conjunction with a compact battery- powered circuit board- microwave electronic module and a user-friendly software interface, this method enables rapid in-vivo water amount assessment of plants by a handheld device for potential use in the field. PMID:25918549

  9. Prediction of human core body temperature using non-invasive measurement methods

    NASA Astrophysics Data System (ADS)

    Niedermann, Reto; Wyss, Eva; Annaheim, Simon; Psikuta, Agnes; Davey, Sarah; Rossi, René Michel

    2014-01-01

    The measurement of core body temperature is an efficient method for monitoring heat stress amongst workers in hot conditions. However, invasive measurement of core body temperature (e.g. rectal, intestinal, oesophageal temperature) is impractical for such applications. Therefore, the aim of this study was to define relevant non-invasive measures to predict core body temperature under various conditions. We conducted two human subject studies with different experimental protocols, different environmental temperatures (10 °C, 30 °C) and different subjects. In both studies the same non-invasive measurement methods (skin temperature, skin heat flux, heart rate) were applied. A principle component analysis was conducted to extract independent factors, which were then used in a linear regression model. We identified six parameters (three skin temperatures, two skin heat fluxes and heart rate), which were included for the calculation of two factors. The predictive value of these factors for core body temperature was evaluated by a multiple regression analysis. The calculated root mean square deviation (rmsd) was in the range from 0.28 °C to 0.34 °C for all environmental conditions. These errors are similar to previous models using non-invasive measures to predict core body temperature. The results from this study illustrate that multiple physiological parameters (e.g. skin temperature and skin heat fluxes) are needed to predict core body temperature. In addition, the physiological measurements chosen in this study and the algorithm defined in this work are potentially applicable as real-time core body temperature monitoring to assess health risk in broad range of working conditions.

  10. Non-Invasive Brain-to-Brain Interface (BBI): Establishing Functional Links between Two Brains

    PubMed Central

    Yoo, Seung-Schik; Kim, Hyungmin; Filandrianos, Emmanuel; Taghados, Seyed Javid; Park, Shinsuk

    2013-01-01

    Transcranial focused ultrasound (FUS) is capable of modulating the neural activity of specific brain regions, with a potential role as a non-invasive computer-to-brain interface (CBI). In conjunction with the use of brain-to-computer interface (BCI) techniques that translate brain function to generate computer commands, we investigated the feasibility of using the FUS-based CBI to non-invasively establish a functional link between the brains of different species (i.e. human and Sprague-Dawley rat), thus creating a brain-to-brain interface (BBI). The implementation was aimed to non-invasively translate the human volunteer’s intention to stimulate a rat’s brain motor area that is responsible for the tail movement. The volunteer initiated the intention by looking at a strobe light flicker on a computer display, and the degree of synchronization in the electroencephalographic steady-state-visual-evoked-potentials (SSVEP) with respect to the strobe frequency was analyzed using a computer. Increased signal amplitude in the SSVEP, indicating the volunteer’s intention, triggered the delivery of a burst-mode FUS (350 kHz ultrasound frequency, tone burst duration of 0.5 ms, pulse repetition frequency of 1 kHz, given for 300 msec duration) to excite the motor area of an anesthetized rat transcranially. The successful excitation subsequently elicited the tail movement, which was detected by a motion sensor. The interface was achieved at 94.0±3.0% accuracy, with a time delay of 1.59±1.07 sec from the thought-initiation to the creation of the tail movement. Our results demonstrate the feasibility of a computer-mediated BBI that links central neural functions between two biological entities, which may confer unexplored opportunities in the study of neuroscience with potential implications for therapeutic applications. PMID:23573251

  11. Non-Invasive Prenatal Diagnosis of Lethal Skeletal Dysplasia by Targeted Capture Sequencing of Maternal Plasma

    PubMed Central

    Wang, Yaoshen; Chen, Chao; Gao, Changxin; Yu, Song; Liu, Yan; Song, Wei; Asan; Zhu, Hongmei; Yang, Ling; Deng, Hongmei; Su, Yue; Yi, Xin

    2016-01-01

    Background Since the discovery of cell-free foetal DNA in the plasma of pregnant women, many non-invasive prenatal testing assays have been developed. In the area of skeletal dysplasia diagnosis, some PCR-based non-invasive prenatal testing assays have been developed to facilitate the ultrasound diagnosis of skeletal dysplasias that are caused by de novo mutations. However, skeletal dysplasias are a group of heterogeneous genetic diseases, the PCR-based method is hard to detect multiple gene or loci simultaneously, and the diagnosis rate is highly dependent on the accuracy of the ultrasound diagnosis. In this study, we investigated the feasibility of using targeted capture sequencing to detect foetal de novo pathogenic mutations responsible for skeletal dysplasia. Methodology/Principal Findings Three families whose foetuses were affected by skeletal dysplasia and two control families whose foetuses were affected by other single gene diseases were included in this study. Sixteen genes related to some common lethal skeletal dysplasias were selected for analysis, and probes were designed to capture the coding regions of these genes. Targeted capture sequencing was performed on the maternal plasma DNA, the maternal genomic DNA, and the paternal genomic DNA. The de novo pathogenic variants in the plasma DNA data were identified using a bioinformatical process developed for low frequency mutation detection and a strict variant interpretation strategy. The causal variants could be specifically identified in the plasma, and the results were identical to those obtained by sequencing amniotic fluid samples. Furthermore, a mean of 97% foetal specific alleles, which are alleles that are not shared by maternal genomic DNA and amniotic fluid DNA, were identified successfully in plasma samples. Conclusions/Significance Our study shows that capture sequencing of maternal plasma DNA can be used to non-invasive detection of de novo pathogenic variants. This method has the potential

  12. Non-invasive assessment of adrenocortical function in captive Nile crocodiles (Crocodylus niloticus).

    PubMed

    Ganswindt, Stefanie B; Myburgh, Jan G; Cameron, Elissa Z; Ganswindt, Andre

    2014-11-01

    The occurrence of stress-inducing factors in captive crocodilians is a concern, since chronic stress can negatively affect animal health and reproduction, and hence production. Monitoring stress in wild crocodiles could also be beneficial for assessing the state of health in populations which are potentially threatened by environmental pollution. In both cases, a non-invasive approach to assess adrenocortical function as a measure of stress would be preferable, as animals are not disturbed during sample collection, and therefore sampling is feedback-free. So far, however, such a non-invasive method has not been established for any crocodilian species. As an initial step, we therefore examined the suitability of two enzyme-immunoassays, detecting faecal glucocorticoid metabolites (FGMs) with a 11β,21-diol-20-one and 5β-3α-ol-11-one structure, respectively, for monitoring stress-related physiological responses in captive Nile crocodiles (Crocodylus niloticus). An adrenocorticotropic hormone (ACTH) challenge was performed on 10 sub-adult crocodiles, resulting in an overall increase in serum corticosterone levels of 272% above the pre-injection levels 5h post-injection. Saline-treated control animals (n=8) showed an overall increase of 156% in serum corticosterone levels 5h post-administration. Faecal samples pre- and post-injection could be obtained from three of the six individually housed crocodiles, resulting in FGM concentrations 136-380% above pre-injection levels, always detected in the first sample collected post-treatment (7-15 days post-injection). FGM concentrations seem comparatively stable at ambient temperatures for up to 72 h post-defaecation. In conclusion, non-invasive hormone monitoring can be used for assessing adrenocortical function in captive Nile crocodiles based on FGM analysis. PMID:25066028

  13. Comparison of Non-Invasive Methods for the Detection of Coronary Atherosclerosis

    PubMed Central

    Bampi, Angela Bacelar Albuquerque; Rochitte, Carlos Eduardo; Favarato, Desiderio; Lemos, Pedro Alves; da Luz, Protásio Lemos

    2009-01-01

    BACKGROUND: Non-invasive detection of atherosclerosis is critical for its prevention. Objective: To correlate non-invasively detectable indicators of coronary atherosclerosis, or Coronary Artery Disease (i.e., classical risk factors, hs-CRP test results, carotid intima-media thickness, endothelial function, ankle-brachial index and calcium score by computed tomography) with the extent of coronary disease assessed by the Friesinger index from conventional coronary angiography. METHODS: We conducted a prospective study of 100 consecutive patients, mean age 55.1 ± 10.7 years, 55% men and 45% women. Patients with acute coronary syndrome, renal dialytic insufficiency, collagen disease and cancer were not included. All patients were subjected to clinical evaluation and laboratory tests. Endothelial function of the brachial artery and carotid artery were evaluated by high-resolution ultrasound; ankle-brachial index and computed tomography for coronary determination of calcium score were also performed, and non-HDL cholesterol and TG/HDL-c ratio were calculated. All patients were subjected to coronary angiography at the request of the assistant physician. We considered patients without an obstructive lesion (< 29% stenosis) demonstrated by coronary angiography to be normal. RESULTS: Univariate analysis showed that calcium score, HDL-c, TG/HDL ratio and IMT were significantly correlated with the Friesinger index. However, multivariate analysis indicated that only calcium score and low HDL-c levels correlated significantly with the extension of CAD. On the other hand, hs-CRP, LDL-c, flow-mediated dilation, and Framingham score did not correlate with the Friesinger index. ROC analysis showed that calcium score, HDL-c and TG-HDL ratio accurately predicted extensive CAD in a statistically significant manner. CONCLUSION: It is possible to approximately determine the presence and extent of CAD by non-invasive methods, especially by calcium score, HDL-c and TG/HDL-c ratio assays

  14. [Non-invasive mechanical ventilation therapy in patients with heart failure].

    PubMed

    Dursunoğlu, Dursun; Dursunoğlu, Neşe

    2012-05-01

    Non-invasive mechanical ventilation (NIMV) therapy in patients with acute heart failure (HF) improves left ventricular functions via decreasing left ventricular afterload and reduces intubation rate and short-term mortality. In patients with chronic HF, NIMV therapy eliminates central and obstructive apneas and Cheyne-Stokes respiration, and improves morbidity. There are essentially three modes of NIMV that are used in the treatment of HF: Continuous positive airway pressure (CPAP), bilevel positive airway pressure (BIPAP) and adaptive servo-ventilation (ASV). Hereby, NIMV therapy in patients with acute and chronic HF is reviewed as well as methods, indications, effectiveness and complications. PMID:22381927

  15. Luminescent Tension-Indicating Orthopedic Strain Gauges for Non-Invasive Measurements Through Tissue

    NASA Technical Reports Server (NTRS)

    Anker, Jeffrey (Inventor); Rogalski, Melissa (Inventor); Anderson, Dakota (Inventor); Heath, Jonathon (Inventor)

    2015-01-01

    Strain gauges that can provide information with regard to the state of implantable devices are described. The strain gauges can exhibit luminescence that is detectable through living tissue, and the detectable luminescent emission can vary according to the strain applied to the gauge. A change in residual strain of the device can signify a loss of mechanical integrity and/or loosening of the implant, and this can be non-invasively detected either by simple visual detection of the luminescent emission or through examination of the emission with a detector such as a spectrometer or a camera.

  16. A new antenna system for microwave non-invasive hyperthermia lipolysis.

    PubMed

    Park, Sangbok; Hwang, Joosung; Kwon, Youngwoo; Cheon, Changyul

    2012-01-01

    In this paper, we present an antenna system for microwave non-invasive hyperthermia lipolysis. The antenna system consists of a circular waveguide antenna radiating electromagnetic waves, AlN (Aluminum Nitride) radome and heat sink. The AlN radome with heat sink helps to extract heat from the skin to keep skin temperature not to rise during heating the lipolysis. The antenna was designed to be operated with TE(21) mode to maintain uniform temperature over wider area. The usability of the proposed system was verified by performing numerical simulation and hyperthermia lipolysis experiments on rats. PMID:23367220

  17. Transport and Non-Invasive Position Detection of Electron Beams from Laser-Plasma Accelerators

    SciTech Connect

    Osterhoff, Jens; Sokollik, Thomas; Nakamura, Kei; Bakeman, Michael; Weingartner, R; Gonsalves, Anthony; Shiraishi, Satomi; Lin, Chen; vanTilborg, Jeroen; Geddes, Cameron; Schroeder, Carl; Esarey, Eric; Toth, Csaba; DeSantis, Stefano; Byrd, John; Gruner, F; Leemans, Wim

    2011-07-20

    The controlled imaging and transport of ultra-relativistic electrons from laser-plasma accelerators is of crucial importance to further use of these beams, e.g. in high peak-brightness light sources. We present our plans to realize beam transport with miniature permanent quadrupole magnets from the electron source through our THUNDER undulator. Simulation results demonstrate the importance of beam imaging by investigating the generated XUV-photon flux. In addition, first experimental findings of utilizing cavity-based monitors for non-invasive beam-position measurements in a noisy electromagnetic laser-plasma environment are discussed.

  18. Novel multi wavelength sensor concept to measure carboxy- and methemoglobin concentration non-invasively

    NASA Astrophysics Data System (ADS)

    Timm, Ulrich; Kraitl, Jens; Gewiss, Helge; Kamysek, Svend; Brock, Beate; Ewald, Hartmut

    2016-03-01

    This paper will describe a novel multi-wavelength photometric method to measure carboxyhemoglobin (COHb) and methemoglobin (MetHb) concentration non-invasively. COHb and MetHb are so called dysfunctional hemoglobin derivatives and they are not able to carry oxygen. Standard pulse oximeters are only able to measure two derivatives, namely oxyhemoglobin (O2Hb) and deoxyhemoglobin (HHb) but the presence of other derivatives in the blood may distort the readings. The paper presents a new approach of a noninvasive sensor system to measure COHb and MetHb and the validation in vivo and in vitro.

  19. [BiPAP (Biphasic Positive Airway Pressure)--an apparatus for non-invasive respiratory support].

    PubMed

    Nørregaard, F O; Vindelev, P O; Juhl, B

    1996-01-22

    Ventilatory support to patients suffering from respiratory insufficiency using a non-invasive technique has gained increasing popularity during the last few years. BiPAP (biphasic positive airway pressure) (Respiconics) offers inspiratory support and expiratory resistance to this group of patients both in the hospital and, in particular, in the home. The apparatus has proven to be effective as for instance a long term support device for patients suffering from neuromuscular diseases, sleep apnoeas and during the postoperative period. It works without pressurized air and is portable. PMID:8638299

  20. Non-invasive temperature measurements by neutron diffraction in aero-engine components

    SciTech Connect

    Holden, T.M.; Root, J.H.; Tennant, D.C.; Leggett, D.

    1995-12-31

    A requirement exists in the aeronautical industry for measuring temperature non-invasively in critical components, such as the turbine disc in an operating engine. Neutron diffraction, unique among nuclear techniques, offers the possibility of measuring both temperature and strain within an operating engine by virtue of the high penetration of neutrons through industrial materials. Static diffraction experiments on Waspaloy and Ti6Al4V showed, by comparison with thermocouples, that both the diffraction peak position and the peak intensity can measure the temperature to within {+-}6 K at 800 K.

  1. A non-invasive test for receptor binding applied to nephrogenic diabetes insipidus.

    PubMed Central

    Britton, K. E.; Tedder, R. S.; Khokhar, A. M.; Brown, N. J.; Davison, A.; Slater, J. D.

    1977-01-01

    Studies in animals have determined the importance of specific receptors to the action of many hormones and drugs. In man, a non-invasive external counting technique has been used and absence of receptor function has been demonstrated in a patient with nephrogenic diabetes insipidus using radioactively labelled arginine vasopressin. This is in contrast to the findings in a patient with pituitary diabetes insipidus and a normal control. These results suggest a model for the study of hormone and drug kinetics in man avoiding multiple samplings of biological fluids. PMID:196275

  2. Non-invasive cardiac mapping in clinical practice: Application to the ablation of cardiac arrhythmias.

    PubMed

    Dubois, Rémi; Shah, Ashok J; Hocini, Mélèze; Denis, Arnaud; Derval, Nicolas; Cochet, Hubert; Sacher, Frédéric; Bear, Laura; Duchateau, Josselin; Jais, Pierre; Haissaguerre, Michel

    2015-01-01

    Ten years ago, electrocardiographic imaging (ECGI) started to demonstrate its efficiency in clinical settings. The initial application to localize focal ventricular arrhythmias such as ventricular premature beats was probably the easiest to challenge and validates the concept. Our clinical experience in using this non-invasive mapping technique to identify the sources of electrical disorders and guide catheter ablation of atrial arrhythmias (premature atrial beat, atrial tachycardia, atrial fibrillation), ventricular arrhythmias (premature ventricular beats) and ventricular pre-excitation (Wolff-Parkinson-White syndrome) is described here. PMID:26403066

  3. [Research on a non-invasive pulse wave detection and analysis system].

    PubMed

    Li, Ting; Yu, Gang

    2008-10-01

    A novel non-invasive pulse wave detection and analysis system has been developed, including the software and the hardware. Bi-channel signals can be acquired, stored and shown on the screen dynamically at the same time. Pulse wave can be reshown and printed after pulse wave analysis and pulse wave velocity analysis. This system embraces a computer which is designed for fast data saving, analyzing and processing, and a portable data sampling machine which is based on a singlechip. Experimental results have shown that the system is stable and easy to use, and the parameters are calculated accurately. PMID:19024446

  4. Non-invasive brain stimulation reveals reorganized cortical outputs in amputees.

    PubMed

    Hall, E J; Flament, D; Fraser, C; Lemon, R N

    1990-08-24

    EMG responses to non-invasive electromagnetic brain stimulation (EMS) were recorded from arm muscles of congenital amputees. Responses were obtained with lower thresholds on the amputated than on the intact side and were evoked from a larger cortical area. Contracting muscles showed increased responses to EMS; the increase was more pronounced on the amputated side. Similar findings were obtained in one traumatic amputee who suffered an early amputation, but not in another patient with a late amputation. We conclude that in congenital amputees there is substantial reorganisation of the corticospinal system and that this may also occur in early traumatic cases. PMID:2243618

  5. Non-invasive imaging methods applied to neo- and paleontological cephalopod research

    NASA Astrophysics Data System (ADS)

    Hoffmann, R.; Schultz, J. A.; Schellhorn, R.; Rybacki, E.; Keupp, H.; Gerden, S. R.; Lemanis, R.; Zachow, S.

    2013-11-01

    Several non-invasive methods are common practice in natural sciences today. Here we present how they can be applied and contribute to current topics in cephalopod (paleo-) biology. Different methods will be compared in terms of time necessary to acquire the data, amount of data, accuracy/resolution, minimum-maximum size of objects that can be studied, of the degree of post-processing needed and availability. Main application of the methods is seen in morphometry and volumetry of cephalopod shells in order to improve our understanding of diversity and disparity, functional morphology and biology of extinct and extant cephalopods.

  6. Non-invasive respiratory support for infants in low- and middle-income countries.

    PubMed

    Jensen, Erik A; Chaudhary, Aasma; Bhutta, Zulfiqar A; Kirpalani, Haresh

    2016-06-01

    The overwhelming majority of neonatal deaths worldwide occur in low- and middle-income countries. Most of these deaths are attributable to respiratory illnesses and complications of preterm birth. The available data suggest that non-invasive continuous positive airway pressure (CPAP) is a safe and cost-effective therapy to reduce neonatal morbidity and mortality in these settings. Bubble CPAP compared to mechanical ventilator-generated CPAP reduces the need for subsequent invasive ventilation in newborn infants. There are limited data on the safety and efficacy of high-flow nasal cannulae in low- and middle-income countries, requiring further study prior to widespread implementation. PMID:26915655

  7. Intercomparison of techniques for the non-invasive measurement of bone mass

    SciTech Connect

    Cohn, S.H.

    1981-01-01

    A variety of methods are presently available for the non-invasive measurement of bone mass of both normal individuals and patients with metabolic disorders. Chief among these methods are radiographic techniques such as radiogrammetry, photon absorptiometry, computer tomography, Compton scattering and neutron activation analysis. In this review, the salient features of the bone measurement techniques are discussed along with their accuracy and precision. The advantages and disadvantages of the various techniques for measuring bone mass are summarized. Where possible, intercomparisons are made of the various techniques.

  8. [Non-invasive mechanical ventilation in postoperative patients. A clinical review].

    PubMed

    Esquinas, A M; Jover, J L; Úbeda, A; Belda, F J

    2015-11-01

    Non-invasive ventilation (NIV) is a method of ventilatory support that is increasing in importance day by day in the management of postoperative respiratory failure. Its role in the prevention and treatment of atelectasis is particularly important in the in the period after thoracic and abdominal surgeries. Similarly, in the transplanted patient, NIV can shorten the time of invasive mechanical ventilation, reducing the risk of infectious complications in these high-risk patients. It has been performed A systematic review of the literature has been performed, including examining the technical, clinical experiences and recommendations concerning the application of NIV in the postoperative period. PMID:25892605

  9. Validation of a non-invasive arterial monitor GATE model for PET

    NASA Astrophysics Data System (ADS)

    Giansiracusa, P. J.; Peake, D. J.; Sobott, B. A.; O'Keefe, G.; Rassool, R. P.

    2014-02-01

    The Non-Invasive Arterial Monitor (NIAM3) is an SiPM based detector system designed for calibrating Positron-Emission Tomography (PET) images without invasive blood sampling. By imaging the radial and ulnar arteries in the wrist directly with a custom built PET system the resultant PET images can be calibrated. An integral step in the development of a complex detector system is the creation of a model which accurately reflects the physical reality being studied. This paper describes the development of a simulation for NIAM which shows good agreement between the model and physical detector setup.

  10. Urine Exosomes for Non-Invasive Assessment of Gene Expression and Mutations of Prostate Cancer

    PubMed Central

    Sadeghi, Neda; Salazar, Guillermo; Shapiro, Edan; Ahn, Jennifer; Lipsky, Michael; Lin, James; Hruby, Greg W.; Badani, Ketan K.; Petrylak, Daniel P.; Benson, Mitchell C.; Donovan, Michael J.; Comper, Wayne D.; McKiernan, James M.

    2016-01-01

    Purpose The analysis of exosome/microvesicle (extracellular vesicles (EVs)) and the RNA packaged within them (exoRNA) has the potential to provide a non-invasive platform to detect and monitor disease related gene expression potentially in lieu of more invasive procedures such as biopsy. However, few studies have tested the diagnostic potential of EV analysis in humans. Experimental Design The ability of EV analysis to accurately reflect prostate tissue mRNA expression was examined by comparing urinary EV TMPRSS2:ERG exoRNA from pre-radical prostatectomy (RP) patients versus corresponding RP tissue in 21 patients. To examine the differential expression of TMPRSS2:ERG across patient groups a random urine sample was taken without prostate massage from a cohort of 207 men including prostate biopsy negative (Bx Neg, n = 39), prostate biopsy positive (Bx Pos, n = 47), post-radical prostatectomy (post-RP, n = 37), un-biopsied healthy age-matched men (No Bx, n = 44), and young male controls (Cont, n = 40). The use of EVs was also examined as a potential platform to non-invasively differentiate Bx Pos versus Bx Neg patients via the detection of known prostate cancer genes TMPRSS2:ERG, BIRC5, ERG, PCA3 and TMPRSS2. Results In this technical pilot study urinary EVs had a sensitivity: 81% (13/16), specificity: 80% (4/5) and an overall accuracy: 81% (17/21) for non-invasive detection of TMPRSS2:ERG versus RP tissue. The rate of TMPRSS2:ERG exoRNA detection was found to increase with age and the expression level correlated with Bx Pos status. Receiver operator characteristic analyses demonstrated that various cancer-related genes could differentiate Bx Pos from Bx Neg patients using exoRNA isolated from urinary EVs: BIRC5 (AUC 0.674 (CI:0.560–0.788), ERG (AUC 0.785 (CI:0.680–0.890), PCA3 (AUC 0.681 (CI:0.567–0.795), TMPRSS2:ERG (AUC 0.744 (CI:0.600–0.888), and TMPRSS2 (AUC 0.637 (CI:0.519–0.754). Conclusion This pilot study suggests that urinary EVs have the potential

  11. A Glucose Sensing Contact Lens: A Non-Invasive Technique for Continuous Physiological Glucose Monitoring

    PubMed Central

    Badugu, Ramachandram; Lakowicz, Joseph R.; Geddes, Chris D.

    2016-01-01

    We have developed a range of glucose sensing contact lenses, using a daily, disposable contact lens embedded with newly developed boronic acid containing fluorophores. Our findings show that our approach may be suitable for the continuous monitoring of tear glucose levels in the range 50–1000 μM, which typically track blood glucose levels, which are ≈5–10 fold higher. Our non-invasive approach may well offer an alternative solution to current invasive glucose monitoring techniques for diabetes, such as “finger pricking.” PMID:27340364

  12. Non-invasive electrocardiogram detection of in vivo zebrafish embryos using electric potential sensors

    NASA Astrophysics Data System (ADS)

    Rendon-Morales, E.; Prance, R. J.; Prance, H.; Aviles-Espinosa, R.

    2015-11-01

    In this letter, we report the continuous detection of the cardiac electrical activity in embryonic zebrafish using a non-invasive approach. We present a portable and cost-effective platform based on the electric potential sensing technology, to monitor in vivo electrocardiogram activity from the zebrafish heart. This proof of principle demonstration shows how electrocardiogram measurements from the embryonic zebrafish may become accessible by using electric field detection. We present preliminary results using the prototype, which enables the acquisition of electrophysiological signals from in vivo 3 and 5 days-post-fertilization zebrafish embryos. The recorded waveforms show electrocardiogram traces including detailed features such as QRS complex, P and T waves.

  13. Transport and Non-Invasive Position Detection of Electron Beams from Laser-Plasma Accelerators

    SciTech Connect

    Osterhoff, J.; Nakamura, K.; Bakeman, M.; Gonsalves, A. J.; Shiraishi, S.; Lin, C.; Tilborg, J. van; Geddes, C. G. R.; Schroeder, C. B.; Esarey, E.; Toth, Cs.; De Santis, S.; Byrd, J. M.; Leemans, W. P.; Sokollik, T.; Weingartner, R.; Gruener, F.

    2010-11-04

    The controlled imaging and transport of ultra-relativistic electrons from laser-plasma accelerators is of crucial importance to further use of these beams, e.g. in high peak-brightness light sources. We present our plans to realize beam transport with miniature permanent quadrupole magnets from the electron source through our THUNDER undulator. Simulation results demonstrate the importance of beam imaging by investigating the generated XUV-photon flux. In addition, first experimental findings of utilizing cavity-based monitors for non-invasive beam-position measurements in a noisy electromagnetic laser-plasma environment are discussed.

  14. Method for Non-Invasive Determination of Chemical Properties of Aqueous Solutions

    NASA Technical Reports Server (NTRS)

    Todd, Paul W. (Inventor); Jones, Alan (Inventor); Thomas, Nathan A. (Inventor)

    2016-01-01

    A method for non-invasively determining a chemical property of an aqueous solution is provided. The method provides the steps of providing a colored solute having a light absorbance spectrum and transmitting light through the colored solute at two different wavelengths. The method further provides the steps of measuring light absorbance of the colored solute at the two different transmitted light wavelengths, and comparing the light absorbance of the colored solute at the two different wavelengths to determine a chemical property of an aqueous solution.

  15. Non-invasive measurements of granular flows by magnetic resonance imaging

    SciTech Connect

    Nakagawa, M.; Altobelli, S.A.; Caprihan, A.; Fukushima, E.; Jeong, E.K.

    1993-01-20

    Magnetic Resonance Imaging (MRI) was used to measure granular-flow in a partially filled, steadily rotating, long, horizontal cylinder. This non-invasive technique can yield statistically averaged two-dimensional concentrations and velocity profiles anywhere in the flow of suitable granular materials. First, rigid body motion of a cylinder fill with granular material was studied to confirm the validity of this method. Then, the density variation of the flowing layer where particles collide and dilate, and the depth of the flowing layer and the flow velocity profile were obtained as a function of the cylinder rotation rate.

  16. Study on non-invasive optical detection of the glucose concentration with scatters

    NASA Astrophysics Data System (ADS)

    Lin, Li-Han; Liao, Chia-Chi; Lo, Yu-Lung

    2015-03-01

    A new scheme to measure the glucose concentration with scatters is proposed for the detection of diabetics. In this study, the measuring technique based on the Stokes-Mueller polarimetry to solve the Mueller matrices of a complex sample containing circular birefringence and depolarization is developed. As a result, the circular birefringence and depolarization which relate to the concentrations of glucose and scattering events in turbid media can be inversely extracted.

  17. Non-invasive assessment of cerebral microcirculation with diffuse optics and coherent hemodynamics spectroscopy

    NASA Astrophysics Data System (ADS)

    Fantini, Sergio; Sassaroli, Angelo; Kainerstorfer, Jana M.; Tgavalekos, Kristen T.; Zang, Xuan

    2016-03-01

    We describe the general principles and initial results of coherent hemodynamics spectroscopy (CHS), which is a new technique for the quantitative assessment of cerebral hemodynamics on the basis of dynamic near-infrared spectroscopy (NIRS) measurements. The two components of CHS are (1) dynamic measurements of coherent cerebral hemodynamics in the form of oscillations at multiple frequencies (frequency domain) or temporal transients (time domain), and (2) their quantitative analysis with a dynamic mathematical model that relates the concentration and oxygen saturation of hemoglobin in tissue to cerebral blood volume (CBV), cerebral blood flow (CBF), and cerebral metabolic rate of oxygen (CMRO2). In particular, CHS can provide absolute measurements and dynamic monitoring of CBF, and quantitative measures of cerebral autoregulation. We report initial results of CBF measurements in hemodialysis patients, where we found a lower CBF (54 +/- 16 ml/(100 g-min)) compared to a group of healthy controls (95 +/- 11 ml/(100 g-min)). We also report CHS measurements of cerebral autoregulation, where a quantitative index of autoregulation (its cutoff frequency) was found to be significantly greater in healthy subjects during hyperventilation (0.034 +/- 0.005 Hz) than during normal breathing (0.017 +/- 0.002 Hz). We also present our approach to depth resolved CHS, based on multi-distance, frequency-domain NIRS data and a two-layer diffusion model, to enhance sensitivity to cerebral tissue. CHS offers a potentially powerful approach to the quantitative assessment and continuous monitoring of local brain perfusion at the microcirculation level, with prospective brain mapping capabilities of research and clinical significance.

  18. Optical Characterization of Single Plasmonic Nanoparticles

    PubMed Central

    Olson, Jana; Dominguez-Medina, Sergio; Hoggard, Anneli; Wang, Lin-Yung; Chang, Wei-Shun; Link, Stephan

    2015-01-01

    This tutorial review surveys the optical properties of plasmonic nanoparticles studied by various single particle spectroscopy techniques. The surface plasmon resonance of metallic nanoparticles depends sensitively on the nanoparticle geometry and its environment, with even relatively minor deviations causing significant changes in the optical spectrum. Because for chemically prepared nanoparticles a distribution of their size and shape is inherent, ensemble spectra of such samples are inhomogeneously broadened, hiding the properties of the individual nanoparticles. The ability to measure one nanoparticle at a time using single particle spectroscopy can overcome this limitation. This review provides an overview of different steady-state single particle spectroscopy techniques that provide detailed insight into the spectral characteristics of plasmonic nanoparticles. PMID:24979351

  19. (Optical characterization techniques applied to ceramic oxides)

    SciTech Connect

    Abraham, M.M.

    1990-10-15

    The traveler collaborated with M.J.M. Leask, J.M. Baker, B. Bleaney, and others at the Clarendon Laboratory, Oxford University, Oxford, UK, to Study Tetragonal rare-earth phosphates and vanadates by optical and magnetic spectroscopy. This work is related to similar studies that have been performed at ORNL by the Synthesis and Properties of Novel Materials Group in the Solid State Division.

  20. Frontal eye field, where art thou? Anatomy, function, and non-invasive manipulation of frontal regions involved in eye movements and associated cognitive operations

    PubMed Central

    Vernet, Marine; Quentin, Romain; Chanes, Lorena; Mitsumasu, Andres; Valero-Cabré, Antoni

    2014-01-01

    The planning, control and execution of eye movements in 3D space relies on a distributed system of cortical and subcortical brain regions. Within this network, the Eye Fields have been described in animals as cortical regions in which electrical stimulation is able to trigger eye movements and influence their latency or accuracy. This review focuses on the Frontal Eye Field (FEF) a “hub” region located in Humans in the vicinity of the pre-central sulcus and the dorsal-most portion of the superior frontal sulcus. The straightforward localization of the FEF through electrical stimulation in animals is difficult to translate to the healthy human brain, particularly with non-invasive neuroimaging techniques. Hence, in the first part of this review, we describe attempts made to characterize the anatomical localization of this area in the human brain. The outcome of functional Magnetic Resonance Imaging (fMRI), Magneto-encephalography (MEG) and particularly, non-invasive mapping methods such a Transcranial Magnetic Stimulation (TMS) are described and the variability of FEF localization across individuals and mapping techniques are discussed. In the second part of this review, we will address the role of the FEF. We explore its involvement both in the physiology of fixation, saccade, pursuit, and vergence movements and in associated cognitive processes such as attentional orienting, visual awareness and perceptual modulation. Finally in the third part, we review recent evidence suggesting the high level of malleability and plasticity of these regions and associated networks to non-invasive stimulation. The exploratory, diagnostic, and therapeutic interest of such interventions for the modulation and improvement of perception in 3D space are discussed. PMID:25202241