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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. 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.

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

    PubMed Central

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

    2014-01-01

    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

  4. 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.

  5. 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

  6. 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.

  7. 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.

  8. 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

  9. Non-invasive tissue temperature measurements based on quantitative diffuse optical spectroscopy (DOS) of water

    PubMed Central

    Chung, SH; Cerussi, AE; Merritt, SI; Ruth, J; Tromberg, BJ

    2012-01-01

    We describe the development of a non-invasive method for quantitative tissue temperature measurements using Broadband diffuse optical spectroscopy (DOS). Our approach is based on well-characterized opposing shifts in near-infrared (NIR) water absorption spectra that appear with temperature and macromolecular binding state. Unlike conventional reflectance methods, DOS is used to generate scattering-corrected tissue water absorption spectra. This allows us to separate the macromolecular bound water contribution from the thermally induced spectral shift using the temperature isosbestic point at 996 nm. The method was validated in intralipid tissue phantoms by correlating DOS with thermistor measurements (R = 0.96) with a difference of 1.1 ± 0.91 °C over a range of 28–48 °C. Once validated, thermal and hemodynamic (i.e. oxy- and deoxy-hemoglobin concentration) changes were measured simultaneously and continuously in human subjects (forearm) during mild cold stress. DOS-measured arm temperatures were consistent with previously reported invasive deep tissue temperature studies. These results suggest that DOS can be used for non-invasive, co-registered measurements of absolute temperature and hemoglobin parameters in thick tissues, a potentially important approach for optimizing thermal diagnostics and therapeutics. PMID:20551502

  10. 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.

  11. Non-invasive characterization of structure and morphology of silk fibroin biomaterials using non-linear microscopy

    PubMed Central

    Rice, William L.; Firdous, Shamaraz; Gupta, Sharad; Hunter, Martin; Foo, Cheryl Wong Po; Wang, Yongzhong; Kim, Hyeon Joo; Kaplan, David L.; Georgakoudi, Irene

    2009-01-01

    Designing biomaterial scaffolds remains a major challenge in tissue engineering. Key to this challenge is improved understanding of the relationships between the scaffold properties and its degradation kinetics, as well as the cell interactions and the promotion of new matrix deposition. Here we present the use of non-linear spectroscopic imaging as a non-invasive method to characterize not only morphological, but also structural aspects of silkworm silk fibroin-based biomaterials, relying entirely on endogenous optical contrast. We demonstrate that two photon excited fluorescence and second harmonic generation are sensitive to the hydration, overall β sheet content and molecular orientation of the sample. Thus, the functional content and high resolution afforded by these non-invasive approaches offer promise for identifying important connections between biomaterial design and functional engineered tissue development. The strategies described also have broader implications for understanding and tracking the remodeling of degradable biomaterials under dynamic conditions both in vitro and in vivo. PMID:18291520

  12. Non-invasive optical mapping of the piglet brain in real time

    NASA Astrophysics Data System (ADS)

    Fantini, Sergio; Franceschini, Maria Angela; Gratton, Enrico; Hueber, Dennis; Rosenfeld, Warren; Maulik, Dev; Stubblefield, Phillip; Stankovic, Mikjan

    1999-04-01

    We have performed non-invasive, real-time optical mapping of the piglet brain during a subcortical injection of autologous blood. The time resolution of the optical maps is 192 ms, thus allowing us to generate a real-time video of the growing subcortical hematoma. The increased absorption at the site of blood injection is accompanied by a decreased absorption at the contralateral brain side. This contralateral decrease in the optical absorption and the corresponding time traces of the cerebral hemoglobin parameters are consistent with a reduced cerebral blood flow caused by the increased intracranial pressure.

  13. 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

  14. Seeing Through the Surface: Non-invasive Characterization of Biomaterial-Tissue Interactions Using Photoacoustic Microscopy.

    PubMed

    Zhang, Yu Shrike; Wang, Lihong V; Xia, Younan

    2016-03-01

    At the intersection of life sciences, materials science, engineering, and medicine, regenerative medicine stands out as a rapidly progressing field that aims at retaining, restoring, or augmenting tissue/organ functions to promote the human welfare. While the field has witnessed tremendous advancements over the past few decades, it still faces many challenges. For example, it has been difficult to visualize, monitor, and assess the functions of the engineered tissue/organ constructs, particularly when three-dimensional scaffolds are involved. Conventional approaches based on histology are invasive and therefore only convey end-point assays. The development of volumetric imaging techniques such as confocal and ultrasonic imaging has enabled direct observation of intact constructs without the need of sectioning. However, the capability of these techniques is often limited in terms of penetration depth and contrast. In comparison, the recently developed photoacoustic microscopy (PAM) has allowed us to address these issues by integrating optical and ultrasonic imaging to greatly reduce the effect of tissue scattering of photons with one-way ultrasound detection while retaining the high optical absorption contrast. PAM has been successfully applied to a number of studies, such as observation of cell distribution, monitoring of vascularization, and interrogation of biomaterial degradation. In this review article, we highlight recent progress in non-invasive and volumetric characterization of biomaterial-tissue interactions using PAM. We also discuss challenges ahead and envision future directions. PMID:26471785

  15. 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

  16. Non-Invasive Detection of Early Retinal Neuronal Degeneration by Ultrahigh Resolution Optical Coherence Tomography

    PubMed Central

    Tudor, Debbie; Kajić, Vedran; Rey, Sara; Erchova, Irina; Považay, Boris; Hofer, Bernd; Powell, Kate A.; Marshall, David; Rosin, Paul L.; Drexler, Wolfgang; Morgan, James E.

    2014-01-01

    Optical coherence tomography (OCT) has revolutionises the diagnosis of retinal disease based on the detection of microscopic rather than subcellular changes in retinal anatomy. However, currently the technique is limited to the detection of microscopic rather than subcellular changes in retinal anatomy. However, coherence based imaging is extremely sensitive to both changes in optical contrast and cellular events at the micrometer scale, and can generate subtle changes in the spectral content of the OCT image. Here we test the hypothesis that OCT image speckle (image texture) contains information regarding otherwise unresolvable features such as organelle changes arising in the early stages of neuronal degeneration. Using ultrahigh resolution (UHR) OCT imaging at 800 nm (spectral width 140 nm) we developed a robust method of OCT image analyses, based on spatial wavelet and texture-based parameterisation of the image speckle pattern. For the first time we show that this approach allows the non-invasive detection and quantification of early apoptotic changes in neurons within 30 min of neuronal trauma sufficient to result in apoptosis. We show a positive correlation between immunofluorescent labelling of mitochondria (a potential source of changes in cellular optical contrast) with changes in the texture of the OCT images of cultured neurons. Moreover, similar changes in optical contrast were also seen in the retinal ganglion cell- inner plexiform layer in retinal explants following optic nerve transection. The optical clarity of the explants was maintained throughout in the absence of histologically detectable change. Our data suggest that UHR OCT can be used for the non-invasive quantitative assessment of neuronal health, with a particular application to the assessment of early retinal disease. PMID:24776961

  17. 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.

  18. 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%.

  19. 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).

  20. 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.

  1. 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

  2. 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

  3. 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.

  4. A new optical method for the non-invasive detection of minimal tissue alterations

    NASA Astrophysics Data System (ADS)

    Charvet, Igor; Thueler, Philippe; Vermeulen, Bernard; Saint-Ghislain, Michel; Biton, Catherine; Jacquet, Jean; Bevilacqua, Fréderic; Depeursinge, Christian; Meda, Paolo

    2002-06-01

    Histological analysis, which is used to detect and diagnose most tissue alterations, requires an invasive biopsy procedure and a time-consuming tissue treatment, which limit its efficiency in providing rapid, cost-effective diagnosis and hinder the longitudinal study of tissue alteration. To address these limitations, we have developed a novel procedure, using the features of elastic-scattering spectroscopy, for a real-time, non-invasive analysis of tissues. We have tested whether this approach can detect in vivo changes in mouse skin induced by a single exposure to either complete Freund's adjuvant or 12-O-tetradecanoylphorbol-13-acetate, two drugs known to induce discrete alterations of epidermis and dermis, without obvious changes on the skin surface. Here we report that the evaluation of localized absorption and reduced scattering coefficients permitted the detection of changes in skin regions that showed histological alterations, but not in regions which failed to be modified by the drugs. Results show that the optical in vivo analysis of small regions has sufficient specificity and sensitivity to detect minimal alterations of superficial tissues. In view of the prominent involvement of mucosal alterations in most human diseases, including carcinomas, the method provides a useful complement to standard biopsy, notably for the in vivo screening of early in situ epithelial alterations.

  5. Non-invasive optical detection of esophagus cancer based on urine surface-enhanced Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Huang, Shaohua; Wang, Lan; Chen, Weiwei; Lin, Duo; Huang, Lingling; Wu, Shanshan; Feng, Shangyuan; Chen, Rong

    2014-09-01

    A surface-enhanced Raman spectroscopy (SERS) approach was utilized for urine biochemical analysis with the aim to develop a label-free and non-invasive optical diagnostic method for esophagus cancer detection. SERS spectrums were acquired from 31 normal urine samples and 47 malignant esophagus cancer (EC) urine samples. Tentative assignments of urine SERS bands demonstrated esophagus cancer specific changes, including an increase in the relative amounts of urea and a decrease in the percentage of uric acid in the urine of normal compared with EC. The empirical algorithm integrated with linear discriminant analysis (LDA) were employed to identify some important urine SERS bands for differentiation between healthy subjects and EC urine. The empirical diagnostic approach based on the ratio of the SERS peak intensity at 527 to 1002 cm-1 and 725 to 1002 cm-1 coupled with LDA yielded a diagnostic sensitivity of 72.3% and specificity of 96.8%, respectively. The area under the receive operating characteristic (ROC) curve was 0.954, which further evaluate the performance of the diagnostic algorithm based on the ratio of the SERS peak intensity combined with LDA analysis. This work demonstrated that the urine SERS spectra associated with empirical algorithm has potential for noninvasive diagnosis of esophagus cancer.

  6. 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.

  7. Phase-Contrast Optical Coherence Tomography: A New Technique for Non-Invasive Angiography

    PubMed Central

    Schwartz, Daniel M.; Fingler, Jeff; Kim, Dae Yu; Zawadzki, Robert J.; Morse, Lawrence S.; Park, Susanna S.; Fraser, Scott E.; Werner, John S.

    2014-01-01

    Purpose Phase-contrast optical coherence tomography (PC-OCT) provides volumetric imaging of the retinal vasculature without the need for intravenous injection of a fluorophore. Here, we compare images from PC-OCT and fluorescein angiography (FA) for normal individuals and patients with age-related macular degeneration and diabetic retinopathy. Design This is an evaluation of a diagnostic technology. Participants 4 patients underwent comparative retinovascular imaging using FA and PC-OCT. Imaging was performed on 1 normal individual, 1 patient with dry age-related macular degeneration, 1 patient with exudative age-related macular degeneration and 1 patient with non-proliferative diabetic retinopathy. Methods FA imaging was performed using a Topcon (TRC-50IX) camera having resolution of 1280 (H) x 1024 (V) pixels. PC-OCT images were generated by software data processing of the entire cross-sectional image from consecutively acquired B-scans. Bulk axial motion was calculated and corrected for each transverse location, reducing the phase noise introduced from eye motion. Phase contrast was calculated through the variance of the motion-corrected phase changes acquired within multiple B-scans at the same position. Repeating these calculations over the entire volumetric scan produced a three-dimensional PC-OCT representation of the vasculature. Main Outcome Measures Feasibility of rendering retinal and choroidal microvasculature using PC-OCT was compared qualitatively to FA, the current gold standard for retinovascular imaging. Results PC-OCT rendered a two-dimensional depth color-coded vasculature map of the retinal and choroidal vasculature non-invasively. The choriocapillaris was imaged with better resolution of microvascular detail using PC-OCT. Areas of geographic atrophy and choroidal neovascularization imaged by FA were depicted by PC-OCT. Regions of capillary non-perfusion from diabetic retinopathy were shown by both imaging techniques; there was not complete

  8. 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

    2013-03-14

    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

  9. 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

  10. 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

  11. 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.

  12. 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

  13. 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.

  14. 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

  15. 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.

  16. Molecular characterization and antibiotic resistance of group G streptococci in Israel: comparison of invasive, non-invasive and carriage isolates.

    PubMed

    Halperin, T; Levine, H; Korenman, Z; Burstein, S; Amber, R; Sela, T; Valinsky, L

    2016-10-01

    Beta-hemolytic group G streptococci (GGS) are increasingly recognized as a source of substantial morbidity, causing mild to severe sporadic infections as well as outbreaks. The purpose of this study was to determine the genetic diversity and antibiotic resistance of GGS in Israel in order to aid in prevention and control. A total of 325 GGS isolates were collected in Israel between 2007 and 2011 from three determined settings: (1) carriage (n = 60), an observational longitudinal carriage study in the IF, (2) non-invasive (n = 166), clinical sporadic and epidemic non-invasive cases in the IDF, and (3) invasive (n = 99) cases of bacteremia collected during this period in Israel from a similar age group, at the national Streptococcal Reference Center. All isolates were characterized genetically and by their antibiotic-resistance profile. emm typing revealed 35 distinct types and subtypes among 228 S. dysgalactiae subsp. equisimilis (SDSE) isolates, with high genetic diversity. An additional 97 GGS were identified as Streptococcus anginosus (SAG). The proportion of SDSE was higher in the invasive (100 %) and non-invasive (63.8 %) isolates compared to the carriage ones (38.3 %). Clindamycin, erythromycin, azithromycin and tetracycline resistance was detected in 6.6 %, 8.6 %, 9.7 % and 37.6 % of isolates, respectively. Overall, the most resistant isolates were in the invasive group and the fewest were in the SAG group. Considerable genetic diversity and common antibiotic resistance were revealed among GGS strains which differed according to the epidemiologic settings. Further clinical, epidemiological and basic research of GGS as a pathogen is warranted.

  17. Molecular characterization and antibiotic resistance of group G streptococci in Israel: comparison of invasive, non-invasive and carriage isolates.

    PubMed

    Halperin, T; Levine, H; Korenman, Z; Burstein, S; Amber, R; Sela, T; Valinsky, L

    2016-10-01

    Beta-hemolytic group G streptococci (GGS) are increasingly recognized as a source of substantial morbidity, causing mild to severe sporadic infections as well as outbreaks. The purpose of this study was to determine the genetic diversity and antibiotic resistance of GGS in Israel in order to aid in prevention and control. A total of 325 GGS isolates were collected in Israel between 2007 and 2011 from three determined settings: (1) carriage (n = 60), an observational longitudinal carriage study in the IF, (2) non-invasive (n = 166), clinical sporadic and epidemic non-invasive cases in the IDF, and (3) invasive (n = 99) cases of bacteremia collected during this period in Israel from a similar age group, at the national Streptococcal Reference Center. All isolates were characterized genetically and by their antibiotic-resistance profile. emm typing revealed 35 distinct types and subtypes among 228 S. dysgalactiae subsp. equisimilis (SDSE) isolates, with high genetic diversity. An additional 97 GGS were identified as Streptococcus anginosus (SAG). The proportion of SDSE was higher in the invasive (100 %) and non-invasive (63.8 %) isolates compared to the carriage ones (38.3 %). Clindamycin, erythromycin, azithromycin and tetracycline resistance was detected in 6.6 %, 8.6 %, 9.7 % and 37.6 % of isolates, respectively. Overall, the most resistant isolates were in the invasive group and the fewest were in the SAG group. Considerable genetic diversity and common antibiotic resistance were revealed among GGS strains which differed according to the epidemiologic settings. Further clinical, epidemiological and basic research of GGS as a pathogen is warranted. PMID:27325440

  18. Phantom materials mimicking the optical properties in the near infrared range for non-invasive fetal pulse oximetry.

    PubMed

    Ley, Sebastian; Stadthalter, Miriam; Link, Dietmar; Laqua, Daniel; Husar, Peter

    2014-01-01

    An optical phantom of the maternal abdomen during pregnancy is an appropriate test environment to evaluate a non-invasive system for fetal pulse oximetry. To recreate the optical properties of maternal tissue, fetal tissue and blood suitable substitutes are required. For this purpose, phantom materials are used, which consist of transparent silicone or water as host material. Cosmetic powder and India ink are investigated as absorbing materials, whereas titanium dioxide particles are examined as scattering medium. Transmittance and reflectance measurements of the samples were performed in the spectral range from 600 nm to 900 nm using integrating sphere technique. The scattering and absorption coefficients and the anisotropy factor were determined using Kubelka-Munk theory. The results were used to compute the required mixture ratios of the respective components to replicate the optical properties of maternal tissue, fetal tissue and blood, and corresponding samples were produced. Their optical properties were investigated in the same manner as mentioned above. The results conform to the values of various types of tissues and blood given in the scientific literature.

  19. Non-invasive optical monitoring of the newborn piglet brain using continuous-wave and frequency-domain spectroscopy

    NASA Astrophysics Data System (ADS)

    Fantini, Sergio; Hueber, Dennis; Franceschini, Maria Angela; Gratton, Enrico; Rosenfeld, Warren; Stubblefield, Phillip G.; Maulik, Dev; Stankovic, Miljan R.

    1999-06-01

    We have used continuous-wave (CW) and frequency-domain spectroscopy to investigate the optical properties of the newborn piglet brain in vivo and non-invasively. Three anaesthetized, intubated, ventilated and instrumented newborn piglets were placed into a stereotaxic instrument for optimal experimental stability, reproducible probe-to-scalp optical contact and 3D adjustment of the optical probe. By measuring the absolute values of the brain absorption and reduced scattering coefficients at two wavelengths (758 and 830 nm), frequency-domain spectroscopy provided absolute readings (in contrast to the relative readings of CW spectroscopy) of cerebral haemoglobin concentration and saturation during experimentally induced perturbations in cerebral haemodynamics and oxygenation. Such perturbations included a modulation of the inspired oxygen concentration, transient brain asphyxia, carotid artery occlusion and terminal brain asphyxia. The baseline cerebral haemoglobin saturation and concentration, measured with frequency-domain spectroscopy, were about 60% and 42 µM respectively. The cerebral saturation values ranged from a minimum of 17% (during transient brain asphyxia) to a maximum of 80% (during recovery from transient brain asphyxia). To analyse the CW optical data, we have (a) derived a mathematical relationship between the cerebral optical properties and the differential pathlength factor and (b) introduced a method based on the spatial dependence of the detected intensity (dc slope method). The analysis of the cerebral optical signals associated with the arterial pulse and with respiration demonstrates that motion artefacts can significantly affect the intensity recorded from a single optode pair. Motion artefacts can be strongly reduced by combining data from multiple optodes to provide relative readings in the dc slope method. We also report significant biphasic changes (initial decrease and successive increase) in the reduced scattering coefficient measured

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. Preliminary results of tympanic membrane displacements using non-invasive optical methods

    NASA Astrophysics Data System (ADS)

    Del Socorro Hernández-Montes, Maria; Muñoz Solís, Silvino; Mendoza Santoyo, Fernando

    2010-08-01

    Quantitative analyses of the tympanic membrane mechanical properties are needed for better understanding of its role in detailed clinical evaluation. Optical methods like Digital Holographic Interferometry (DHI), time averaged holography and ESPI are quite promising for the investigation of biological tissues. Their demonstrated ability to detect displacement changes in quasi and real time and without contacting the sample surface under study provides relevant features, such as clinical and mechanical properties. In this research time averaged vibrations patterns are shown for fresh tympanic membrane specimens taken from post-mortem cats, and subject to acoustic stimuli in the frequency range of 485 Hz up to 10 kHz. The results may provide information about sample mechanical characteristics such as its elasticity coefficient. An important feature of this approach over other techniques previously used to study the vibrations of the tympanic membrane is that it only requires an image and less equipment to carry out the measurements. Good agreement was found between the present and past measurements from previous research work. Results show the usefulness of the method in the medical field in providing relevant data about key mechanical characteristics of biological samples.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. 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

  14. 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.

  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.

  16. 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.

  17. 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

  18. APPLICATION OF LASERS AND LASER-OPTICAL METHODS IN LIFE SCIENCES Non-invasive, MRI-compatible fibreoptic device for functional near-IR reflectometry of human brain

    NASA Astrophysics Data System (ADS)

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

    2011-01-01

    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.

  19. 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

  20. 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.

  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.

  2. 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

  3. Comparison of Optical and Power Doppler Ultrasound Imaging for Non-Invasive Evaluation of Arsenic Trioxide as a Vascular Disrupting Agent in Tumors

    PubMed Central

    Alhasan, Mustafa K.; Liu, Li; Lewis, Matthew A.; Magnusson, Jennifer; Mason, Ralph P.

    2012-01-01

    Small animal imaging provides diverse methods for evaluating tumor growth and acute response to therapy. This study compared the utility of non-invasive optical and ultrasound imaging to monitor growth of three diverse human tumor xenografts (brain U87-luc-mCherry, mammary MCF7-luc-mCherry, and prostate PC3-luc) growing in nude mice. Bioluminescence imaging (BLI), fluorescence imaging (FLI), and Power Doppler ultrasound (PD US) were then applied to examine acute vascular disruption following administration of arsenic trioxide (ATO). During initial tumor growth, strong correlations were found between manual caliper measured tumor volume and FLI intensity, BLI intensity following luciferin injection, and traditional B-mode US. Administration of ATO to established U87 tumors caused significant vascular shutdown within 2 hrs at all doses in the range 5 to 10 mg/kg in a dose dependant manner, as revealed by depressed bioluminescent light emission. At lower doses substantial recovery was seen within 4 hrs. At 8 mg/kg there was >85% reduction in tumor vascular perfusion, which remained depressed after 6 hrs, but showed some recovery after 24 hrs. Similar response was observed in MCF7 and PC3 tumors. Dynamic BLI and PD US each showed similar duration and percent reductions in tumor blood flow, but FLI showed no significant changes during the first 24 hrs. The results provide further evidence for comparable utility of optical and ultrasound imaging for monitoring tumor growth, More specifically, they confirm the utility of BLI and ultrasound imaging as facile assays of the vascular disruption in solid tumors based on ATO as a model agent. PMID:23029403

  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. 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.

  6. 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.

  7. 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

  8. 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

  9. Optical Characterization of a Hollow Fiber Raman Probe toward Non-Invasive Measurements of Living Tissues

    NASA Astrophysics Data System (ADS)

    Mitsuoka, Hiroki; Morita, Shin-ichi; Suzuki, Toshiaki; Matsuura, Yuji; Katsumoto, Yukiteru; Sato, Hidetoshi

    2009-02-01

    The use of a hollow fiber as a Raman probe, which gives strong advantage of a free link in space, was confirmed to be a versatile and standard analytical method, since Raman data obtained through a hollow fiber probe assures a sufficient link to conventional Raman data. In this paper, we confirmed that a Raman spectrum given by the hollow fiber probe becomes identical to a Raman spectrum measured by a conventional approach, if one is multiplied by an optimized coefficient. In addition, Raman signal intensity changes were related to various types of curved geometries of the probe. The Raman signal intensity value at a curved geometry of the probe, which is one of the most frequently used positions, became 0.35 compared to the value at the standard position of the probe (straight lined).

  10. 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

  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. Non-invasive Characterization of the Histopathologic Features of Pulmonary Nodules of the Lung Adenocarcinoma Spectrum using Computer Aided Nodule Assessment and Risk Yield (CANARY) – a Pilot Study

    PubMed Central

    Maldonado, Fabien; Boland, Jennifer M.; Raghunath, Sushravya; Aubry, Marie Christine; Bartholmai, Brian J.; deAndrade, Mariza; Hartman, Thomas E.; Karwoski, Ronald A.; Rajagopalan, Srinivasan; Sykes, Anne-Marie; Yang, Ping; Yi, Eunhee S.; Robb, Richard A.; Peikert, Tobias

    2013-01-01

    Introduction Pulmonary nodules of the adenocarcinoma spectrum are characterized by distinctive morphological and radiological features and variable prognosis. Non-invasive high-resolution computed-tomography (HRCT)-based risk stratification tools are needed to individualize their management. Methods Radiological measurements of histopathologic tissue invasion were developed in a training set of 54 pulmonary nodules of the adenocarcinoma spectrum and validated in 86 consecutively resected nodules. Nodules were isolated and characterized by computer-aided analysis and data were analyzed by Spearman correlation, sensitivity, specificity as well as the positive and negative predictive values. Results Computer Aided Nodule Assessment and Risk Yield (CANARY) can non-invasively characterize pulmonary nodules of the adenocarcinoma spectrum. Unsupervised clustering analysis of HRCT data identified 9 unique exemplars representing the basic radiologic building blocks of these lesions. The exemplar distribution within each nodule correlated well with the proportion of histologic tissue invasion, Spearman R=0.87,p < 0.0001 and 0.89,p < 0.0001 for the training and the validation set, respectively. Clustering of the exemplars in three-dimensional space corresponding to tissue invasion and lepidic growth was used to develop a CANARY decision algorithm, which successfully categorized these pulmonary nodules as “aggressive” (invasive adenocarcinoma) or “indolent” (adenocarcinoma in situ and minimally invasive adenocarcinoma). Sensitivity, specificity, positive predictive value and negative predictive value of this approach for the detection of “aggressive” lesions were 95.4%, 96.8%, 95.4% and 96.8%, respectively in the training set and 98.7%, 63.6%, 94.9% and 87.5%, respectively in the validation set. Conclusion CANARY represents a promising tool to non-invasively risk stratify pulmonary nodules of the adenocarcinoma spectrum. PMID:23486265

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. Non-invasive molecular imaging for preclinical cancer therapeutic development

    PubMed Central

    O'Farrell, AC; Shnyder, SD; Marston, G; Coletta, PL; Gill, JH

    2013-01-01

    Molecular and non-invasive imaging are rapidly emerging fields in preclinical cancer drug discovery. This is driven by the need to develop more efficacious and safer treatments, the advent of molecular-targeted therapeutics, and the requirements to reduce and refine current preclinical in vivo models. Such bioimaging strategies include MRI, PET, single positron emission computed tomography, ultrasound, and optical approaches such as bioluminescence and fluorescence imaging. These molecular imaging modalities have several advantages over traditional screening methods, not least the ability to quantitatively monitor pharmacodynamic changes at the cellular and molecular level in living animals non-invasively in real time. This review aims to provide an overview of non-invasive molecular imaging techniques, highlighting the strengths, limitations and versatility of these approaches in preclinical cancer drug discovery and development. PMID:23488622

  19. 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.

  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. 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.

  2. 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.

  3. Electro-optic sensors dedicated to noninvasive electric field characterization

    NASA Astrophysics Data System (ADS)

    Warzecha, A.; Bernier, M.; Gaborit, G.; Duvillaret, L.; Lasserre, J.-L.

    2009-06-01

    This paper describes non-invasive electro-optic sensors devoted to simultaneous electric field and temperature measurements. Based on Poeckel's effect, these sensors consist in non-centrosymmetric crystals for which an electricfield induces a modification of their refractive indices [1]. Such modification can also be induced by a drift of the crystal temperature [2]. After explanation of the principle, we will illustrate some applications (high power microwave characterization, bioelectromagnetism, electric field mapping of high voltage devices) for which electro-optic sensors give excellent performances. These sensors perform vectorial E-field measurement (modulus and phase of each E-field components) with both high spatial and temporal resolutions. As they are pigtailed, long distance remote sensing is then allowed. They are also non-invasive due to their fully dielectric design. However, their sensitivity remains quite low for electromagnetic compatibility and their size remains too important for bioelectromagnetism studies in Petry dishes for example. So, two ways of improvement are pursued. The first one consists in using Fabry-Perot microcavities based on LiNbO3 optical waveguide to dramatically reduce sensors size. The second one consists in an optical processing (optical carrier rejection) of the laser probe beam to increase the sensor sensitivity for high frequency measurements. We will present first results concerning these improvements and also results that have been performed in free space with a fully automated setup in both frequency and time domains.

  4. 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.

  5. A Reporting System for Non-Invasive Cardiovascular Investigations

    PubMed Central

    Covvey, H.D.; Van Horik, M.; Hum, J.; Sole, M.J.; Schwartz, L.; Rakowski, H.; Wigle, E.D.

    1978-01-01

    A computer-based system has been developed to support the collection, reporting and storage of data acquired during non-invasive cardiac investigations. Currently the system serves 1-D echocardiography and graded exercise testing. Optical mark forms are used to record information in computer-readable form. A terminal station consisting of a CRT terminal, an optical mark reader and a printer is used for input and output from a central minicomputer database management system. Even when the costs associated with database storage are included, the overall cost of the system compares favorably with the option of using typists to produce reports.

  6. 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

  7. 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.

  8. Cellular Phone Enabled Non-Invasive Tissue Classifier

    PubMed Central

    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

  9. 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.

  10. 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).

  11. [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.

  12. 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.

  13. [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

  14. Optical Coherence Tomography for nanoparticles quantitative characterization

    NASA Astrophysics Data System (ADS)

    Trojanowski, Michał; Kraszewski, Maciej; StrÄ kowski, Marcin R.; Pluciński, Jerzy

    2015-08-01

    The unique features of nanocomposite materials depend on the type and size of nanoparticles, as well as their placement in the composite matrices. Therefore the nanocomposites manufacturing process requires inline control over certain parameters of nanoparticles such as dispersion and concentration. Keeping track of nanoparticles parameters inside a matrix is currently a difficult task due to lack of a fast, reliable and cost effective way of measurement that can be used for large volume samples. For this purpose the Optical Coherence Tomography (OCT) has been used. OCT is an optical measurement method, which is a non-destructive and non-invasive technique. It is capable of creating tomographic images of inner structure by gathering depth related backscattered signal from scattering particles. In addition, it can analyse, in a single shot, area of the centimetre range with resolution up to single micrometres. Still to increase OCT measurement capabilities we are using additional system extensions such as Spectroscopic OCT (SOCT). With such addition, we are able to measure depth related parameters such as scattering spectra and intensity of backscattered signal. Those parameters allow us to quantitatively estimate nanoparticles concentration. Gaining those, information allows to calculate volume concentration of nanoparticles. In addition, we analyse metallic oxides nanoparticles. To fully characterize nanoparticles it is necessary to find and differentiate those that are single particles from agglomerated ones. In this contribution we present our research results on using the LCI based measurement techniques for evaluation of materials with nanoparticles. The laboratory system and signal processing algorithms are going to be shown in order to express the usefulness of this method for inline constant monitoring of the nanocomposite material fabrication.

  15. Non-invasive Evaluation for Epilepsy Surgery

    PubMed Central

    IWASAKI, Masaki; JIN, Kazutaka; NAKASATO, Nobukazu; TOMINAGA, Teiji

    2016-01-01

    Epilepsy surgery is aimed to remove the brain tissues that are indispensable for generating patient’s epileptic seizures. There are two purposes in the pre-operative evaluation: localization of the epileptogenic zone and localization of function. Surgery is planned to remove possible epileptogenic zone while preserving functional area. Since no single diagnostic modality is superior to others in identifying and localizing the epileptogenic zone, multiple non-invasive evaluations are performed to estimate the location of the epileptogenic zone after concordance between evaluations. Essential components of non-invasive pre-surgical evaluation of epilepsy include detailed clinical history, long-term video-electroencephalography monitoring, epilepsy-protocol magnetic resonance imaging (MRI), and neuropsychological testing. However, a significant portion of drug-resistant epilepsy is associated with no or subtle MRI lesions or with ambiguous electro-clinical signs. Additional evaluations including fluoro-deoxy glucose positron emission tomography (FDG-PET), magnetoencephalography and ictal single photon emission computed tomography can play critical roles in planning surgery. FDG-PET should be registered on three-dimensional MRI for better detection of focal cortical dysplasia. All diagnostic tools are complementary to each other in defining the epileptogenic zone, so that it is always important to reassess the data based on other results to pick up or confirm subtle abnormalities. PMID:27627857

  16. 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.

  17. 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

  18. 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.

  19. Non-invasive exploration in an environmentally sensitive world

    USGS Publications Warehouse

    Livo, K.E.; Knepper, D.H.

    2004-01-01

    Modern remote sensing provides a means for locating and characterizing exposed mineralized systems in many parts of the world. These capabilities are non-invasive and help target specific areas for more detailed exploration. An example of how remote sensing technology can be used is evident from a study of the Questa Mining District, New Mexico. Analysis of low spectral resolution data from the Landsat Thematic Mapper satellite system clearly shows the regional distribution of two broad mineral groups often associated with mineralized systems: clay-carbonate-sulfate and iron oxides-iron hydroxides. Analysis of high spectral resolution data from the Airborne Visible and Infrared Imaging System (AVIRIS) shows the occurrence and distribution of many individual mineral species that characterize the pattern of hydrothermally altered rocks in the district.

  20. 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.

  1. 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

  2. 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

  3. 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.

  4. Characterizing optical chirality

    SciTech Connect

    Bliokh, Konstantin Y.; Nori, Franco

    2011-02-15

    We examine the recently introduced measure of chirality of a monochromatic optical field [Y. Tang and A. E. Cohen, Phys. Rev. Lett. 104, 163901 (2010)] using the momentum (plane-wave) representation and helicity basis. Our analysis clarifies the physical meaning of the measure of chirality and unveils its close relation to the polarization helicity, spin angular momentum, energy density, and Poynting energy flow. We derive the operators of the optical chirality and of the corresponding chiral momentum, which acquire remarkably simple forms in the helicity representation.

  5. 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.

  6. 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

  7. [Non-invasive explorations of the carotid arteries (author's transl)].

    PubMed

    Persson, A V; Dyer, V E

    1981-01-01

    For the non-invasive evaluation of patients suspected of having extracranial carotid artery disease, the non-invasive vascular laboratory at the Lahey Clinic, Boston, Massachusetts uses three tests. Carotid phonoangiography (C.P.A.) by itself is 60% accurate, the Kartchner-McRae Oculoplethysmograph (O.P.G.) by itself 80% accurate, and the Echoflow doppler arterial imager, by itself 90% accurate. These examinations are used for surveillance of high-risk patients and to determine the need for carotid arteriography. In a series of 94 patients, the combination of these non-invasive methods yielded one false negative and 2 false positive studies, for an overall accuracy of 95%.

  8. 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

  9. 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.

  10. Non-invasive blood glucose monitor based on spectroscopy using a smartphone.

    PubMed

    Dantu, Vishnu; Vempati, Jagannadh; Srivilliputhur, Srinivasan

    2014-01-01

    Development of a novel method for non-invasive measurement of blood glucose concentration using smartphone is discussed. Our research work has three major contributions to society and science. First, we modified and extended the Beer-Lambert's law in physics to accommodate for multiple wavelengths. This extension can aid researchers who wish to perform optical spectroscopy. Second, we successfully developed a creative and non-invasive way for diabetic patients to measure glucose levels via a smartphone. Researchers and chemists can now use their smartphones to determine the absorbance and, therefore, concentration of a chemical. Third, we created an inexpensive way to perform optical spectroscopy by using a smartphone. Monitoring blood glucose using a smartphone application that simply uses equipment already available on smartphones will improve the lives of diabetic patients who can continuously check their blood glucose levels while avoiding the current inconvenient, unhygienic, and costly invasive glucose meters.

  11. 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.

  12. 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.

  13. 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

  14. 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

  15. Non invasive tools for the diagnosis of liver cirrhosis.

    PubMed

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

    2014-12-28

    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.

  16. Optical subsystem characterization in laboratory

    NASA Astrophysics Data System (ADS)

    Nicolosi, P.; Zuppella, P.; Corso, A. J.; Polito, V.; Pelizzo, M. G.; Mariscal, J. F.; Rouanet, N.; Mine, P. O.; Quémerais, E.; Maria, J. L.

    2011-05-01

    The Bepi Colombo mission will explore the Mercury planet and its environment. Probing of Hermean Exosphere By Ultraviolet Spectroscopy (PHEBUS) is one of the instruments of the payload. It is a double spectrometer for Extreme Ultraviolet (EUV) and Far Ultraviolet (FUV) spectral regions devoted to the characterization of Mercury's exosphere. In this work we will present the calibration philosophy that will be applied to the Flight Model, and explain how a full instrument calibration can be derived from the wholly characterization of the optical subsystems through the Mueller Matrix formalism. The experimental results concerning of PHEBUS prototype optical subsystems are presented, which have been performed in the 55 - 315 nm range by using the normal incidence reflectometer at LUXOR Laboratory (CNR - Institute for Photonics and Nanotechnology, Padova).

  17. 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

  18. Non-invasive methods of assessing the tear film.

    PubMed

    Yokoi, Norihiko; Komuro, Aoi

    2004-03-01

    The interaction between the tear film and the ocular surface epithelium is crucial for the maintenance of ocular surface health; interference with this relationship may cause dry eye. Several diagnostic techniques have been developed to assess the tear film and diagnose dry eye but many of these tests are invasive and modify the parameter which they are designed to measure. Non-invasive or minimally invasive tests may overcome this problem and provide more reproducible and objective data. One test of this kind is meniscometry, which is particularly useful in assessing tear volume indirectly by measuring tear meniscus radius. The newly developed video-meniscometer, which enables calculation of the meniscus radius digitally, is useful for the diagnosis of tear-deficient dry eye. Video-meniscometry also has other applications, to the study of tear and eye drop turnover, determining the indication for punctal plugs and in demonstrating dysfunction of the tear meniscus. Interferometry of the tear film lipid layer is useful in screening and evaluating dry eye severity and in selecting dry eye candidates for punctal occlusion. It is also useful for analysing tear lipid layer pathophysiology more clearly, especially in combination with meniscometry. Meibometry is a minimally invasive technique to quantify the amount of meibomian lipid on the lid margin. Lipid is blotted onto a plastic tape and the change in optical density is used to calculate lipid uptake. Laser meibometry has increased the scope of this technique for the assessment of meibomian gland dysfunction; also, the delivery of lipids from the lid reservoir to the preocular tear film can be analysed using interferometry and laser meibometry. The present report reviews the application of these techniques to the study of tear film physiology and dry eye.

  19. Non-invasive blood pressure measurement in mice.

    PubMed

    Feng, Minjie; DiPetrillo, Keith

    2009-01-01

    Hypertension is a leading cause of heart attack, stroke, and kidney failure and represents a serious medical issue worldwide. The genetic basis of hypertension is well-established, but few causal genes have been identified thus far. Non-invasive blood pressure measurements are a critical component of high-throughput genetic studies to identify genes controlling blood pressure. Whereas this technique is fairly routine for blood pressure measurements in rats, non-invasive blood pressure measurement in mice has proven to be more challenging. This chapter describes an experimental protocol measuring blood pressure in mice using a CODA non-invasive blood pressure monitoring system. This method enables accurate blood pressure phenotyping in mice for linkage or mutagenesis studies, as well as for other experiments requiring high-throughput blood pressure measurement.

  20. Non-invasive wearable electrochemical sensors: a review.

    PubMed

    Bandodkar, Amay J; Wang, Joseph

    2014-07-01

    Wearable sensors have garnered considerable recent interest owing to their tremendous promise for a plethora of applications. Yet the absence of reliable non-invasive chemical sensors has greatly hindered progress in the area of on-body sensing. Electrochemical sensors offer considerable promise as wearable chemical sensors that are suitable for diverse applications owing to their high performance, inherent miniaturization, and low cost. A wide range of wearable electrochemical sensors and biosensors has been developed for real-time non-invasive monitoring of electrolytes and metabolites in sweat, tears, or saliva as indicators of a wearer's health status. With continued innovation and attention to key challenges, such non-invasive electrochemical sensors and biosensors are expected to open up new exciting avenues in the field of wearable wireless sensing devices and body-sensor networks, and thus find considerable use in a wide range of personal health-care monitoring applications, as well as in sport and military applications.

  1. Non-invasive Assessments of Adipose Tissue Metabolism In Vitro.

    PubMed

    Abbott, Rosalyn D; Borowsky, Francis E; Quinn, Kyle P; Bernstein, David L; Georgakoudi, Irene; Kaplan, David L

    2016-03-01

    Adipose tissue engineering is a diverse area of research where the developed tissues can be used to study normal adipose tissue functions, create disease models in vitro, and replace soft tissue defects in vivo. Increasing attention has been focused on the highly specialized metabolic pathways that regulate energy storage and release in adipose tissues which affect local and systemic outcomes. Non-invasive, dynamic measurement systems are useful to track these metabolic pathways in the same tissue model over time to evaluate long term cell growth, differentiation, and development within tissue engineering constructs. This approach reduces costs and time in comparison to more traditional destructive methods such as biochemical and immunochemistry assays and proteomics assessments. Towards this goal, this review will focus on important metabolic functions of adipose tissues and strategies to evaluate them with non-invasive in vitro methods. Current non-invasive methods, such as measuring key metabolic markers and endogenous contrast imaging will be explored.

  2. 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.

  3. Non-Invasive Imaging of Peripheral Nerves

    PubMed Central

    Rangavajla, Gautam; Mokarram, Nassir; Masoodzadehgan, Nazanin; Pai, S. Balakrishna; Bellamkonda, Ravi V.

    2015-01-01

    Recent developments in the field of peripheral nerve imaging extend the capabilities of imaging modalities to assist in the diagnosis and treatment of patients with peripheral nerve maladies. Methods such as MRI and its derivative DTI, ultrasound, and PET are capable of assessing nerve structure and function following injury and relating the state of the nerve to electrophysiological and histological analysis. Of the imaging methods surveyed here, each offered unique and interesting advantages related to the field. MRI offered the opportunity to visualize immune activity on the injured nerve throughout the course of the regeneration process, and DTI offered numerical characterization of the injury and the ability to develop statistical bases for diagnosing injury. Ultrasound extends imaging to the treatment phase by enabling more precise analgesic applications following surgery, and PET represents a novel method of assessing nerve injury through analysis of relative metabolism rates in injured and healthy tissue. Exciting new possibilities to enhance and extend the abilities of imaging methods are also discussed here, including innovative contrast agents, some of which enable multimodal imaging approaches and present opportunities for treatment application. PMID:25766202

  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. 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

  6. 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 ...

  7. 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.

  8. 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.

  9. Non-invasive mouse models of post-traumatic osteoarthritis.

    PubMed

    Christiansen, B A; Guilak, F; Lockwood, K A; Olson, S A; Pitsillides, A A; Sandell, L J; Silva, M J; van der Meulen, M C H; Haudenschild, D R

    2015-10-01

    Animal models of osteoarthritis (OA) are essential tools for investigating the development of the disease on a more rapid timeline than human OA. Mice are particularly useful due to the plethora of genetically modified or inbred mouse strains available. The majority of available mouse models of OA use a joint injury or other acute insult to initiate joint degeneration, representing post-traumatic osteoarthritis (PTOA). However, no consensus exists on which injury methods are most translatable to human OA. Currently, surgical injury methods are most commonly used for studies of OA in mice; however, these methods may have confounding effects due to the surgical/invasive injury procedure itself, rather than the targeted joint injury. Non-invasive injury methods avoid this complication by mechanically inducing a joint injury externally, without breaking the skin or disrupting the joint. In this regard, non-invasive injury models may be crucial for investigating early adaptive processes initiated at the time of injury, and may be more representative of human OA in which injury is induced mechanically. A small number of non-invasive mouse models of PTOA have been described within the last few years, including intra-articular fracture of tibial subchondral bone, cyclic tibial compression loading of articular cartilage, and anterior cruciate ligament (ACL) rupture via tibial compression overload. This review describes the methods used to induce joint injury in each of these non-invasive models, and presents the findings of studies utilizing these models. Altogether, these non-invasive mouse models represent a unique and important spectrum of animal models for studying different aspects of PTOA. PMID:26003950

  10. Speckle-variance optical coherence tomography: a novel approach to skin cancer characterization using vascular patterns.

    PubMed

    Markowitz, Orit; Schwartz, Michelle; Minhas, Sumeet; Siegel, Daniel M

    2016-01-01

    Non-invasive imaging devices are currently being utilized in research and clinical settings to help visualize, characterize, anddiagnose cancers of the skin. Speckle-variance optical coherence tomography (svOCT) is one such technology that offers considerable promise for non-invasive, real time detection of skin cancers given its added ability to show changes in microvasculature. We present four early lesions of the face namely sebaceous hyperplasia, basal cell skin cancer, pigmented actinic keratosis, and malignant melanoma in situ that each display different important identification markers on svOCT. Up until now, svOCT has mainly been evaluated for lesion diagnosis using transversal (vertical) sections. Our preliminary svOCT findings use dynamic en face (horizontal) visualization to differentiate lesions based on their specific vascular organizations. These observed patterns further elucidate the potential of this imaging device to become a powerful tool in patient disease assessment. PMID:27617454

  11. Non-invasive optical modulation of local vascular permeability

    NASA Astrophysics Data System (ADS)

    Choi, Myunghwan; Choi, Chulhee

    2011-03-01

    For a systemically administered drug to act, it first needs to cross the vascular wall. This step represents a bottleneck for drug development, especially in the brain or retina, where tight junctions between endothelial cells form physiological barriers. Here, we demonstrate that femtosecond pulsed laser irradiation focused on the blood vessel wall induces transient permeabilization of plasma. Nonlinear absorption of the pulsed laser enabled the noninvasive modulation of vascular permeability with high spatial selectivity in three dimensions. By combining this method with systemic injection, we could locally deliver molecular probes in various tissues, such as brain cortex, meninges, ear, striated muscle, and bone. We suggest this method as a novel delivery tool for molecular probes or drugs.

  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. 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.

  14. 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.

  15. 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

  16. 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

  17. Non-invasive diagnosis of internal carotid artery dissections.

    PubMed Central

    Müllges, W; Ringelstein, E B; Leibold, M

    1992-01-01

    Arteriography is thought to be mandatory for the diagnosis of internal carotid artery (ICA) dissection. With the introduction of transcranial Doppler sonography (TCD) and magnetic resonance imaging (MRI), however, this is no longer the case. In 13 consecutive patients with ICA dissections the diagnosis was made by means of non-invasive tests including extracranial and transcranial Doppler sonography, contrast enhanced computed tomography (ceCT), and, in five patients, MRI. Intra-arterial digital subtraction angiography used as the gold standard in all cases was confirmative. Extracranial and transcranial ultrasound findings indicative of the diagnosis could be identified. MRI directly demonstrated the intramural haematoma and the false lumen of the dissected artery. These non-invasive techniques also allowed for repetitive follow up examinations. They were, however, unable to demonstrate false aneurysms in the chronic state. Results show that the diagnosis of carotid dissection can be made by means of cerebrovascular ultrasound and MRI. Images PMID:1538235

  18. 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.

  19. How to reduce invasiveness in non-invasive ventilation.

    PubMed

    Chiandotto, Valeria

    2012-10-01

    Non invasive ventilation plays a key role in neonatal intensive care unit (NICU) activity and several instruments have recently been developed that are designed to maintain positive pressure in order to improve functional residual capacity of the lung. However, devices used to provide non-invasive respiratory assistance are frequently a cause of discomfort when applied to a fragile neonate. Indeed, they are applied for lengthy periods in low birth weight (VLBW) infants. In addition to these side effects we have to consider several other stressful events. In our opinion, reducing invasiveness in the NICU is a process where the main steps are recognizing a need for the organization of diagnostic and therapeutic procedures with respect for the rhythm of the newborn, recognizing the fragility of preterm newborns and their brain plasticity, improving environmental standards in both structural terms and staff behaviour, and promoting the active role of parents in supporting the development of the newborn.

  20. 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.

  1. 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

  2. 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.

  3. Non-invasive, investigative methods in skin aging.

    PubMed

    Longo, C; Ciardo, S; Pellacani, G

    2015-12-01

    A precise and noninvasive quantification of aging is of outmost importance for in vivo assessment of the skin aging "stage", and thus acts to minimize it. Several bioengineering methods have been proposed to objectively, precisely, and non-invasively measure skin aging, and to detect early skin damage, that is sub-clinically observable. In this review we have described the most relevant methods that have emerged from recently introduced technologies, aiming at quantitatively assessing the effects of aging on the skin.

  4. 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.

  5. 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.

  6. 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.

  7. Optical arbitrary waveform characterization using linear spectrograms.

    PubMed

    Jiang, Zhi; Leaird, Daniel E; Long, Christopher M; Boppart, Stephen A; Weiner, Andrew M

    2010-08-01

    We demonstrate the first application of linear spectrogram methods based on electro-optic phase modulation to characterize optical arbitrary waveforms generated under spectral line-by-line control. This approach offers both superior sensitivity and self-referencing capability for retrieval of periodic high repetition rate optical arbitrary waveforms.

  8. Optical arbitrary waveform characterization using linear spectrograms

    PubMed Central

    Jiang, Zhi; Leaird, Daniel E.; Long, Christopher M.; Boppart, Stephen A.; Weiner, Andrew M.

    2010-01-01

    We demonstrate the first application of linear spectrogram methods based on electro-optic phase modulation to characterize optical arbitrary waveforms generated under spectral line-by-line control. This approach offers both superior sensitivity and self-referencing capability for retrieval of periodic high repetition rate optical arbitrary waveforms. PMID:21359161

  9. Non-invasive determination of port wine stain anatomy and physiology for optimal laser treatment strategies

    NASA Astrophysics Data System (ADS)

    van Gemert, Martin J. C.; Nelson, J. Stuart; Milner, Thomas E.; Smithies, Derek J.; Verkruysse, Wim; de Boer, Johannes F.; Lucassen, Gerald W.; Goodman, Dennis M.; Tanenbaum, B. Samuel; Norvang, Lill T.; Svaasand, Lars O.

    1997-05-01

    The treatment of port wine stains (PWSs) using a flashlamp-pumped pulsed dye laser is often performed using virtually identical irradiation parameters. Although encouraging clinical results have been reported, we propose that lasers will only reach their full potential provided treatment parameters match individual PWS anatomy and physiology. The purpose of this paper is to review the progress made on the technical development and clinical implementation of (i) infrared tomography (IRT), optical reflectance spectroscopy (ORS) and optical low-coherence reflectometry (OLCR) to obtain in vivo diagnostic data on individual PWS anatomy and physiology and (ii) models of light and heat propagation, predicting irreversible vascular injury in human skin, to select optimal laser wavelength, pulse duration, spot size and radiant exposure for complete PWS blanching in the fewest possible treatment sessions. Although non-invasive optical sensing techniques may provide significant diagnostic data, development of a realistic model will require a better understanding of relevant mechanisms for irreversible vascular injury.

  10. 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

  11. 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

  12. [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.

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

    PubMed

    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.

  14. 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.

  15. 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

  16. 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

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. Non-invasive pulmonary function test on Morquio Patients

    PubMed Central

    Kubaski, Francyne; Tomatsu, Shunji; Patel, Pravin; Shimada, Tsutomu; Xie, Li; Yasuda, Eriko; Mason, Robert; Mackenzie, William G.; Theroux, Mary; Bober, Michael B.; Oldham, Helen M.; Orii, Tadao; Shaffer, Thomas H.

    2015-01-01

    In clinical practice, respiratory function tests are difficult to perform in Morquio syndrome patients due to their characteristic skeletal dysplasia, small body size and lack of cooperation of young patients, where in some cases, conventional spirometry for pulmonary function is too challenging. To establish feasible clinical pulmonary endpoints and determine whether age impacts lung function in Morquio patients non-invasive pulmonary tests and conventional spirometry were evaluated. The non-invasive pulmonary tests: impulse oscillometry system, pneumotachography, and respiratory inductance plethysmography in conjunction with conventional spirometry were evaluated in twenty-two Morquio patients (18 Morquio A and 4 Morquio B) (7 males), ranging from 3 and 40 years of age. Twenty-two patients were compliant with non-invasive tests (100%) with exception of IOS (81.8%–18 patients). Seventeen patients (77.3%) were compliant with spirometry testing. All subjects had normal vital signs at rest including > 95% oxygen saturation, end tidal CO2 (38–44 mmHg), and age-appropriate heart rate (mean=98.3, standard deviation=19) (two patients were deviated). All patients preserved normal values in impulse oscillometry system, pneumotachography, and respiratory inductance plethysmography, although predicted forced expiratory volume total (72.8 ± 6.9 SE%) decreased with age and was below normal; phase angle (35.5 ± 16.5 Degrees), %Rib Cage (41.6 ± 12.7%), resonant frequency, and forced expiratory volume in one second/forced expiratory volume total (110.0 ± 3.2 SE%) were normal and not significantly impacted by age. The proposed non-invasive pulmonary function tests are able to cover a greater number of patients (young patients and/or wheel-chair bound), thus providing a new diagnostic approach for the assessment of lung function in Morquio syndrome which in many cases may be difficult to evaluate. Morquio patients studied herein demonstrated no clinical or functional signs

  2. Non-invasive pulmonary function test on Morquio patients.

    PubMed

    Kubaski, Francyne; Tomatsu, Shunji; Patel, Pravin; Shimada, Tsutomu; Xie, Li; Yasuda, Eriko; Mason, Robert; Mackenzie, William G; Theroux, Mary; Bober, Michael B; Oldham, Helen M; Orii, Tadao; Shaffer, Thomas H

    2015-08-01

    In clinical practice, respiratory function tests are difficult to perform in Morquio syndrome patients due to their characteristic skeletal dysplasia, small body size and lack of cooperation of young patients, where in some cases, conventional spirometry for pulmonary function is too challenging. To establish feasible clinical pulmonary endpoints and determine whether age impacts lung function in Morquio patients non-invasive pulmonary tests and conventional spirometry were evaluated. The non-invasive pulmonary tests: impulse oscillometry system, pneumotachography, and respiratory inductance plethysmography in conjunction with conventional spirometry were evaluated in twenty-two Morquio patients (18 Morquio A and 4 Morquio B) (7 males), ranging from 3 to 40 years of age. Twenty-two patients were compliant with non-invasive tests (100%) with the exception of IOS (81.8%-18 patients). Seventeen patients (77.3%) were compliant with spirometry testing. All subjects had normal vital signs at rest including >95% oxygen saturation, end tidal CO2 (38-44 mmHg), and age-appropriate heart rate (mean=98.3, standard deviation=19) (two patients were deviated). All patients preserved normal values in the impulse oscillometry system, pneumotachography, and respiratory inductance plethysmography, although predicted forced expiratory total (72.8±6.9 SE%) decreased with age and was below normal; phase angle (35.5±16.5°), %rib cage (41.6±12.7%), resonant frequency, and forced expiratory volume in 1 s/forced expiratory volume total (110.0±3.2 SE%) were normal and not significantly impacted by age. The proposed non-invasive pulmonary function tests are able to cover a greater number of patients (young patients and/or wheel-chair bound), thus providing a new diagnostic approach for the assessment of lung function in Morquio syndrome which in many cases may be difficult to evaluate. Morquio patients studied herein demonstrated no clinical or functional signs of restrictive and

  3. 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.

  4. 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

  5. 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.

  6. 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

  7. 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

  8. 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

  9. Non-invasive diagnosis of liver fibrosis and cirrhosis.

    PubMed

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

    2015-11-01

    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.

  10. Non-invasive primate head restraint using thermoplastic masks

    PubMed Central

    Drucker, Caroline B.; Carlson, Monica L.; Toda, Koji; DeWind, Nicholas K.; Platt, Michael L.

    2015-01-01

    Background The success of many neuroscientific studies depends upon adequate head fixation of awake, behaving animals. Typically, this is achieved by surgically affixing a head-restraint prosthesis to the skull. New Method Here we report the use of thermoplastic masks to non-invasively restrain monkeys’ heads. Mesh thermoplastic sheets become pliable when heated and can then be molded to an individual monkey’s head. After cooling, the custom mask retains this shape indefinitely for day-to-day use. Results We successfully trained rhesus macaques (Macaca mulatta) to perform cognitive tasks while wearing thermoplastic masks. Using these masks, we achieved a level of head stability sufficient for high-resolution eye-tracking and intracranial electrophysiology. Comparison with Existing Method Compared with traditional head-posts, we find that thermoplastic masks perform at least as well during infrared eye-tracking and single-neuron recordings, allow for clearer magnetic resonance image acquisition, enable freer placement of a transcranial magnetic stimulation coil, and impose lower financial and time costs on the lab. Conclusions We conclude that thermoplastic masks are a viable non-invasive form of primate head restraint that enable a wide range of neuroscientific experiments. PMID:26112334

  11. 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

  12. 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

  13. Non-invasive and micro-destructive investigation of the Domus Aurea wall painting decorations.

    PubMed

    Clementi, Catia; Ciocan, Valeria; Vagnini, Manuela; Doherty, Brenda; Tabasso, Marisa Laurenzi; Conti, Cinzia; Brunetti, Brunetto Giovanni; Miliani, Costanza

    2011-10-01

    The paper reports on the exploitation of an educated multi-technique analytical approach based on a wide non invasive step followed by a focused micro-destructive step, aimed at the minimally invasive identification of the pigments decorating the ceiling of the Gilded Vault of the Domus Aurea in Rome. The combination of elemental analysis with molecular characterization provided by X-ray fluorescence and UV-vis spectroscopies, respectively, allowed for the in situ non-invasive identification of a remarkable number of pigments, namely Egyptian blue, green earth, cinnabar, red ochre and an anthraquinonic lake. The study was completed with the Raman analysis of two bulk samples, in particular, SERS measurements allowed for the speciation of the anthraquinonic pigment. Elemental mapping by scanning electron microscopy-energy dispersive spectrometer combined with micro-fluorimetry on cross-section gave an insight into both the distribution of different blend of pigments and on the nature of the inorganic support of the red dye. PMID:21805319

  14. 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

  15. 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.

  16. [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

  17. 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

  18. 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

  19. Non-invasive distress evaluation in preterm newborn infants.

    PubMed

    Manfredi, C; Bocchi, L; Orlandi, S; Calisti, M; Spaccaterra, L; Donzelli, G P

    2008-01-01

    With the increased survival of very preterm infants, there is a growing concern for their developmental outcomes. Infant cry characteristics reflect the development and possibly the integrity of the central nervous system. In this paper, relationships between fundamental frequency (F(0)) and vocal tract resonance frequencies (F(1)-F(3)) are investigated for a set of preterm newborns, by means of a multi-purpose voice analysis tool (BioVoice), characterised by high-resolution and tracking capabilities. Also, first results about possible distress occurring during cry in preterm newborn infants, as related to the decrease of central blood oxygenation, are presented. To this aim, a recording system (Newborn Recorder) has been developed, that allows synchronised, non-invasive monitoring of blood oxygenation and audio recordings of newborn infant's cry. The method has been applied to preterm newborns at the Intensive Care Unit, A.Meyer Children Hospital, Firenze, Italy.

  20. 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

  1. Non-Invasive Tension Measurement Devices for Parachute Cordage

    NASA Technical Reports Server (NTRS)

    Litteken, Douglas A.; Daum, Jared S.

    2016-01-01

    The need for lightweight and non-intrusive tension measurements has arisen alongside the development of high-fidelity computer models of textile and fluid dynamics. In order to validate these computer models, data must be gathered in the operational environment without altering the design, construction, or performance of the test article. Current measurement device designs rely on severing a cord and breaking the load path to introduce a load cell. These load cells are very reliable, but introduce an area of high stiffness in the load path, directly affecting the structural response, adding excessive weight, and possibly altering the dynamics of the parachute during a test. To capture the required data for analysis validation without affecting the response of the system, non-invasive measurement devices have been developed and tested by NASA. These tension measurement devices offer minimal impact to the mass, form, fit, and function of the test article, while providing reliable, axial tension measurements for parachute cordage.

  2. 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.

  3. Non-invasive brain stimulation in neglect rehabilitation: an update.

    PubMed

    Müri, René Martin; Cazzoli, Dario; Nef, Tobias; Mosimann, Urs P; Hopfner, Simone; Nyffeler, Thomas

    2013-01-01

    Here, we review the effects of non-invasive brain stimulation such as transcranial magnetic stimulation (TMS) or transcranial direct current stimulation (tDCS) in the rehabilitation of neglect. We found 12 studies including 172 patients (10 TMS studies and 2 tDCS studies) fulfilling our search criteria. Activity of daily living measures such as the Barthel Index or, more specifically for neglect, the Catherine Bergego Scale were the outcome measure in three studies. Five studies were randomized controlled trials with a follow-up time after intervention of up to 6 weeks. One TMS study fulfilled criteria for Class I and one for Class III evidence. The studies are heterogeneous concerning their methodology, outcome measures, and stimulation parameters making firm comparisons and conclusions difficult. Overall, there are however promising results for theta-burst stimulation, suggesting that TMS is a powerful add-on therapy in the rehabilitation of neglect patients.

  4. Non-Invasive Brain Stimulation in Neglect Rehabilitation: An Update

    PubMed Central

    Müri, René Martin; Cazzoli, Dario; Nef, Tobias; Mosimann, Urs P.; Hopfner, Simone; Nyffeler, Thomas

    2013-01-01

    Here, we review the effects of non-invasive brain stimulation such as transcranial magnetic stimulation (TMS) or transcranial direct current stimulation (tDCS) in the rehabilitation of neglect. We found 12 studies including 172 patients (10 TMS studies and 2 tDCS studies) fulfilling our search criteria. Activity of daily living measures such as the Barthel Index or, more specifically for neglect, the Catherine Bergego Scale were the outcome measure in three studies. Five studies were randomized controlled trials with a follow-up time after intervention of up to 6 weeks. One TMS study fulfilled criteria for Class I and one for Class III evidence. The studies are heterogeneous concerning their methodology, outcome measures, and stimulation parameters making firm comparisons and conclusions difficult. Overall, there are however promising results for theta-burst stimulation, suggesting that TMS is a powerful add-on therapy in the rehabilitation of neglect patients. PMID:23772209

  5. 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.

  6. 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

  7. 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

  8. 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

  9. 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.

  10. A study of oxygen transfer in shake flasks using a non-invasive oxygen sensor.

    PubMed

    Gupta, Atul; Rao, Govind

    2003-11-01

    We describe a study of oxygen transfer in shake flasks using a non-invasive optical sensor. This study investigates the effect of different plugs, presence of baffles, and the type of media on the dissolved oxygen profiles during Escherichia coli fermentation. We measured the volumetric mass transfer coefficient (k(L)a) under various conditions and also the resistances of the various plugs. Finally, we compared shake flask k(L)a with that from a stirred tank fermentor. By matching k(L)a's we were able to obtain similar growth and recombinant protein product formation kinetics in both a fermentor and a shake flask. These results provide a quantitative comparison of fermentations in a shake flask vs. a bench-scale fermentor and should be valuable in guiding scale-up efforts.

  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. 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.

  13. 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.

  14. 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.

  15. Characterization of Semiconductor Materials Using AOTF Instruments

    NASA Technical Reports Server (NTRS)

    Li, G. P.; Cheng, L. J.

    1997-01-01

    A non-invasive characterization of silicon-on-insulator (SOI) wafers using white light interference measured by an AOTF polarimetric hyperspectral imaging instrument will be presented an an illustration of the technology potential. Experiments provided high resolution thickness maps of both silicon and oxide layers with accuracy and observed optically active imperfections and distributions in the structure.

  16. A new quantitative method for the non-invasive documentation of morphological damage in paintings using RTI surface normals.

    PubMed

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

    2014-07-09

    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.

  17. 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.

  18. 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

  19. 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.

  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. 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.

  2. 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

  3. The neurophysiology of language: Insights from non-invasive brain stimulation in the healthy human brain.

    PubMed

    Hartwigsen, Gesa

    2015-09-01

    With the advent of non-invasive brain stimulation (NIBS), a new decade in the study of language has started. NIBS allows for testing the functional relevance of language-related brain activation and enables the researcher to investigate how neural activation changes in response to focal perturbations. This review focuses on the application of NIBS in the healthy brain. First, some basic mechanisms will be introduced and the prerequisites for carrying out NIBS studies of language are addressed. The next section outlines how NIBS can be used to characterize the contribution of the stimulated area to a task. In this context, novel approaches such as multifocal transcranial magnetic stimulation and the condition-and-perturb approach are discussed. The third part addresses the combination of NIBS and neuroimaging in the study of plasticity. These approaches are particularly suited to investigate short-term reorganization in the healthy brain and may inform models of language recovery in post-stroke aphasia.

  4. 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

  5. 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.

  6. [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

  7. 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

  8. 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

  9. Non-invasive techniques for the measurement of bone mineral.

    PubMed

    Seeman, E; Martin, T J

    1989-05-01

    Non-invasive, safe and precise techniques for measuring bone mineral density are available and have an important role in the detection, prevention and treatment of bone loss associated with aging, menopause and many illnesses affecting women and men. The three most widely accessible and established techniques for measuring regional bone mineral density are single and dual photon absorptiometry and quantitative computed tomography. A technique of greater accuracy, dual energy X-ray absorptiometry, has only recently become available. These techniques have made it possible to measure the magnitude, time course and regional specificity of the skeleton's response to ageing, menopause and illness. A better understanding of the clinical epidemiology of fractures and the mechanisms responsible for bone loss has been obtained. Practical information has been obtained about the dose, duration and efficacy of oestrogen replacement therapy in preventing perimenopausal bone loss and the benefits and limitations of different forms of exercise on bone mineral density in healthy postmenopausal women. The beneficial effect of dietary calcium on peak bone mineral density and in decreasing bone loss in cortical bone has been documented. Information regarding the prevention and treatment of bone loss in exogenous hypercortisolism and the magnitude and reversibility of bone loss associated with many diseases which affect bone has been obtained. One of the most important clinical applications of these techniques is the assessment of the efficacy of treatment of patients with postmenopausal osteoporosis. As antifracture efficacy is not readily measurable, considerable information is being obtained about many potentially useful forms of therapy that may prevent bone loss and increase bone mineral density. The role of these non-invasive methods in the assessment of fracture risk and the need for oestrogen or other therapy in an individual who has attained a low peak bone mass or has risk

  10. 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.

  11. 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

  12. 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.

  13. 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.

  14. Identification of the proteomic variations of invasive relative to non-invasive non-functional pituitary adenomas.

    PubMed

    Zhan, Xianquan; Desiderio, Dominic M; Wang, Xiaowei; Zhan, Xiaohan; Guo, Tianyao; Li, Maoyu; Peng, Fang; Chen, Xiaoyu; Yang, Haiyan; Zhang, Pengfei; Li, Xuejun; Chen, Zhuchu

    2014-08-01

    The incomplete surgery section of invasive non-functional pituitary adenomas (NFPAs) carries the increased risks of complications and requires adjuvant radiotherapy and medications. It is necessary to clarify the molecular mechanisms and markers of invasiveness to guide the management of NFPA patients. The study aimed to proteomic variations of invasive and non-invasive NFPAs and sought the protein markers for invasive NFPAs. Invasive (n = 4) and non-invasive (n = 4) NFPA tissues were analyzed (n = 3-5/each tissue) with 2DE and PDQuest software. Twenty-four high-resolution 2DE gels were quantitatively compared to determine differentially expressed proteins (DEPs) between invasive and non-invasive NFPAs. Approximately 1200 protein spots were detected in each 2DE map, and 103 differential spots (64 upregulated and 39 downregulated) were identified. Among those 103 differential spots, 57 DEPs (30 upregulated and 27 downregulated) were characterized with peptide mass fingerprint and MS/MS. Gene-ontology (GO) and ingenuity pathway analyses of those DEPs revealed pathway networks including mitochondrial dysfunction, oxidative stress, mitogen-activated protein kinase signaling abnormality, TR/RXR activation, proteolysis abnormality, ketogenesis and ketolysis, cyclin-dependent kinase C signaling abnormality, and amyloid processing that were significantly associated with invasive characteristics of invasive NFPA. Those data demonstrate that proteomic variations exist between invasive and non-invasive NFPAs. 2DE-based comparative proteomics is an effective approach to identify proteomic variations and pathway network variations. Those findings will serve as a basis to understand the molecular mechanisms of invasive NFPAs and to discover protein markers to effectively manage patients with invasive NFPAs. PMID:24729304

  15. 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.

  16. Non-invasive diagnosis of mitral regurgitation by Doppler echocardiography.

    PubMed Central

    Blanchard, D; Diebold, B; Peronneau, P; Foult, J M; Nee, M; Guermonprez, J L; Maurice, P

    1981-01-01

    The value of Doppler echocardiography for the non-invasive diagnosis of mitral regurgitation was studied blindly in 161 consecutive invasively investigated adult patients. Regurgitation was graded from 0 to 3 at selective left ventricular angiography. The Doppler echocardiographic examination was considered to be positive when a disturbed systolic flow was found within the left atrium behind the aorta or the anterior leaflet of the mitral valve. The test was considered to be negative in the absence of a regurgitant jet. The level of the signal to noise ratio was checked by the recording of the ventricular filling flow. The study was performed in 131 cases from the left side of the sternum and in 101 cases from the apex. There were no false positives and thus the specificity was 100 per cent. The 20 false negatives were all in patients with grade 1 regurgitation. Thus only some (33%) instances of mild regurgitation were misdiagnosed, and the sensitivity for moderate to severe mitral regurgitation was 100 per cent. PMID:7236465

  17. 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.

  18. 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

  19. 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.

  20. Exploring non-invasive methods to assess pain in sheep.

    PubMed

    Stubsjøen, Solveig M; Flø, Andreas S; Moe, Randi O; Janczak, Andrew M; Skjerve, Eystein; Valle, Paul S; Zanella, Adroaldo J

    2009-12-01

    The aim of this study was to determine whether changes in eye temperature, measured using infrared thermography (IRT), and heart rate variability (HRV) can detect moderate levels of pain in sheep. Six ewes received the following treatments: 1) noxious ischaemic stimulus by application of a forelimb tourniquet (S), 2) noxious ischaemic stimulus and flunixin meglumine (S+F), and 3) flunixin meglumine (F). Maximum eye temperature, HRV, mechanical nociceptive threshold, blood pressure and behaviour were recorded for up to 60 min, including 15 min of baseline, 30 min during intervention and 15 min post-intervention. There was a tendency towards a decrease in the heart rate variability parameters RMSSD (the root mean square of successive R-R intervals) and SDNN (the standard deviation of all interbeat intervals) in treatment S compared to treatment F, and a significant increase in the same parameters between test day 1 and 3. A reduction in eye temperature was detected for all treatments during intervention, but no difference was found between S and F and S+N and F during intervention. The eye temperature decreased more in test day 2 and 3 compared to test day 1 during intervention. A significant reduction for both lip licking and vocalisation was observed between test day 1 and 3, and forward facing ears was the ear posture most frequently recorded in test day 1. We suggest that HRV is a sensitive, non-invasive method to assess mild to moderate pain in sheep, whereas IRT is a less sensitive method.

  1. 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.

  2. 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.

  3. 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

  4. Bioengineering approach to non-invasive measurement of body composition.

    PubMed

    Dubin, S; Nissanov, J; Zietz, S; Schrope, B; Naim, A; Morano, R; Hanania, R

    1994-01-01

    Measurement of body fat percentage is essential for medical care and research. The "gold standard" method for humans is underwater weighing, which is clearly inappropriate for infants, sick people and non-human animals. The corresponding criterion method for animals is comminution of the carcass followed by extraction of the fat with a volatile solvent such as ether. Our goal has been to develop a method for body composition (fat percentage) for use in animals and humans which is non-invasive and minimally intrusive, independent of variation in body conformation and fat distribution, and reasonable in cost. In one variant, our approach to this problem has been to move Archimedes' principle "on to dry land." The subject's volume is determined by measuring the differential buoyancy in comfortably breathable light (low density) and heavy atmospheres. In another, we use "structured light," in which a pattern of illumination is cast on the patient. The image is acquired using a video camera and the geometrical spatial coordinates of a large number of points on the surface of the subject are acquired. This permits the computation of the surface area and volume of the subject; which, combined with the weight, determines the fat percentage. PMID:7948641

  5. 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.

  6. 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

  7. [Non-invasive Genetic Prenatal Testing - A Serious Challenge for Society as a Whole].

    PubMed

    Zerres, K

    2015-04-01

    Non-invasive genetic prenatal tests nowadays allow a highly reliable identification of pregnancies with foetal aneuploidies. Due to the general availability of these tests for all pregnant women, non-invasive genetic prenatal testing raises many ethical questions whieh can only be answered by a debate focused on society as a whole.

  8. [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.

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. 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.

  14. 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.

  15. 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

  16. Simple setup for optical characterization of microlenses

    NASA Astrophysics Data System (ADS)

    Perrin, Stephane; Baranski, Maciej; Passilly, Nicolas; Froehly, Luc; Albero, Jorge; Bargiel, Sylwester; Gorecki, Christophe

    2014-07-01

    Scientific articles focusing on fabrication of micro-components often evaluate their optical performances by techniques such as scanning electron microscopy or surface topography only. However, deriving the optical characteristics from the shape of the optical element requires using propagation algorithms. In this paper, we present a simple and intuitive method, based on the measurement of the intensity point spread function generated by the micro-component. The setup is less expensive than common systems and does not require heavy equipments, since it requires only a microscope objective, a CMOS camera and a displacement stage. This direct characterization method consists in scanning axially and recording sequentially the focal volume. Our system, in transmissive configuration, consists in the investigation of the focus generated by the microlens, allowing measuring the axial and lateral resolutions, estimating the Strehl ratio and calculating the numerical aperture of the microlens. The optical system can also be used in reflective configuration in order to characterize micro-reflective components such as molds. The fixed imaging configuration allows rapid estimation of quality and repeatability of fabricated micro-optical elements.

  17. 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

  18. 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.

  19. Non-invasive prenatal testing: ethical issues explored.

    PubMed

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

    2010-03-01

    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

  20. Non-invasive measurement of pressure gradients using ultrasound

    NASA Astrophysics Data System (ADS)

    Olesen, Jacob B.; Traberg, Marie S.; Pihl, Michael J.; Jensen, Jørgen A.

    2013-03-01

    A non-invasive method for estimating 2-D pressure gradients from ultrasound vector velocity data is presented. The method relies on in-plane vector velocity elds acquired using the Transverse Oscillation method. The pressure gradients are estimated by applying the Navier-Stokes equations for isotropic uids to the estimated velocity elds. The velocity elds were measured for a steady ow on a carotid bifurcation phantom (Shelley Medical, Canada) with a 70% constriction on the internal branch. Scanning was performed with a BK8670 linear transducer (BK Medical, Denmark) connected to a BK Medical 2202 UltraView Pro Focus scanner. The results are validated through nite element simulations of the carotid ow model where the geometry is determined from MR images. This proof of concept study was conducted at nine ultrasound frames per second. Estimated pressure gradients along the longitudinal direction of the constriction varied from 0 kPa/m to 10 kPa/m with a normalized bias of -9.1% for the axial component and -7.9% for the lateral component. The relative standard deviation of the estimator, given in reference to the peak gradient, was 28.4% in the axial direction and 64.5% in the lateral direction. A study made across the constriction was also conducted. This yielded magnitudes from 0 kPa/m to 7 kPa/m with a normalized bias of -5.7% and 13.9% for the axial and lateral component, respectively. The relative standard deviations of this study were 45.2% and 83.2% in the axial and lateral direction, respectively.

  1. 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

  2. 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

    2016-02-17

    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.

  3. 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

  4. 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.

  5. 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

  6. 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.

  7. 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

  8. 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.

  9. Non-invasive, label-free cell counting and quantitative analysis of adherent cells using digital holography.

    PubMed

    Mölder, A; Sebesta, M; Gustafsson, M; Gisselson, L; Wingren, A Gjörloff; Alm, K

    2008-11-01

    Manual cell counting is time consuming and requires a high degree of skill on behalf of the person performing the count. Here we use a technique that utilizes digital holography, allowing label-free and completely non-invasive cell counting directly in cell culture vessels with adherent viable cells. The images produced can provide both quantitative and qualitative phase information from a single hologram. The recently constructed microscope Holomonitor (Phase Holographic Imaging AB, Lund, Sweden) combines the commonly used phase contrast microscope with digital holography, the latter giving us the possibility of achieving quantitative information on cellular shape, area, confluence and optical thickness. This project aimed at determining the accuracy and repeatability of cell counting measurements using digital holography compared to the conventional manual cell counting method using a haemocytometer. The collected data were also used to determine cell size and cellular optical thickness. The results show that digital holography can be used for non-invasive automatic cell counting as precisely as conventional manual cell counting. PMID:19017223

  10. Magneto-Optical Characterization of Compound Semiconductors

    NASA Astrophysics Data System (ADS)

    Agool, Ibrahim R.

    Available from UMI in association with The British Library. The subject matter of this thesis lies within the area of the physics of semiconductor crystals and more particularly is concerned with the characterization of compound semiconductors using the magneto-optical excitation studies for their importance in the field of device technology. In the first part of this thesis a full study is reported for bulk indium phosphide which is important as substrate material for device fabrication. Measurements have shown that the MCD-ODMR technique is a powerful tool in the investigation of ground state transitions of bulk substrate semiconductors. It has also been shown that the optical technique can be used to explore native defects and transition metal ions in semiconductors. It is also shown in the thesis that an important method used in the characterization of semiconductor superlattices is the use of CO_2 optically pumped far-infrared lasers for studies in quantum wells. This method described as optically detected cyclotron resonance (ODCR), where FIR induced changes in luminescence intensity at resonance has allowed the investigation of non-parabolicity and subband structure for both conduction and valence bands in GaAs. ODCR results at FIR frequencies are compared with measurements performed at microwave frequencies. We have demonstrated that the sensitivity and resolution of FIR-ODCR allows the investigation of multilayer (low dimensional) GaAs/GaAlAs systems with different well widths, where one can monitor the emission from each well independently and examine the effective mass versus well thickness. For the first time we have observed the exchange interaction between donor and acceptor pairs. A Hall Effect system is described for the electrical characterization of doped ZnSe grown at Heriot-Watt University using molecular beam epitaxy (MBE) for new optoelectronic devices such as blue light emitting diodes and blue lasers.

  11. Optical characterization of nanoporous AAO sensor substrate

    NASA Astrophysics Data System (ADS)

    Kassu, Aschalew; Farley, Carlton W.; Sharma, Anup

    2014-05-01

    Nanoporous anodic aluminum oxide (AAO) has been investigated as an ideal and cost-effective chemical and biosensing platform. In this paper, we report the optical properties of periodic 100 micron thick nanoporous anodic alumina membranes with uniform and high density cylindrical pores penetrating the entire thickness of the substrate, ranging in size from 18 nm to 150 nm in diameter and pore periods from 44 nm to 243 nm. The surface geometry of the top and bottom surface of each membrane is studied using atomic force microscopy. The optical properties including transmittance, reflectance, and absorbance spectra on both sides of each substrate are studied and found to be symmetrical. It is observed that, as the pore size increases, the peak resonance intensity in transmittance decreases and in absorbance increases. The effects of the pore sizes on the optical properties of the bare nanoporous membranes and the benefit of using arrays of nanohole arrays with varying hole size and periodicity as a chemical sensing platform is also discussed. To characterize the optical sensing technique, transmittance and reflectance measurements of various concentrations of a standard chemical adsorbed on the bare nanoporous substrates are investigated. The preliminary results presented here show variation in transmittance and reflectance spectra with the concentration of the chemical used or the amount of the material adsorbed on the surface of the substrate.

  12. 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

  13. 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.

  14. 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

  15. 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.

  16. 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

  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. 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

  19. 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.

  20. Non-invasive assessment of neonatal brain oxygen metabolism: A review of newly available techniques.

    PubMed

    Liu, Peiying; Chalak, Lina F; Lu, Hanzhang

    2014-10-01

    Because oxidative metabolism is the primary form of energy production in the brain, the amount of oxygen consumed by the brain, denoted by a physiological parameter termed cerebral metabolic rate of oxygen (CMRO2), represents a key marker for tissue viability and brain function. Quantitative assessment of cerebral oxygen metabolism in the neonate may provide an important marker in better understanding normal brain development and in making diagnosis and treatment decisions in neonatal brain injuries. Measurement of CMRO2 in humans has been a challenging task, particularly in neonates. Recently, several promising techniques have been proposed to quantify neonatal CMRO2 and the purpose of this article is to provide a technical review of these techniques. Among these, we will focus the review on the NIRS optic based methods and MRI methods which are non-invasive, have been applied in normal and sick newborns and show great potentials. Potential clinical prospects of CMRO2 techniques are discussed in the context of their advantages, challenges and limitations.

  1. 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.

  2. 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.

  3. 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.

  4. Intracranial Pressure Monitoring: Invasive versus Non-Invasive Methods—A Review

    PubMed Central

    Raboel, P. H.; Bartek, J.; Andresen, M.; Bellander, B. M.; Romner, B.

    2012-01-01

    Monitoring of intracranial pressure (ICP) has been used for decades in the fields of neurosurgery and neurology. There are multiple techniques: invasive as well as noninvasive. This paper aims to provide an overview of the advantages and disadvantages of the most common and well-known methods as well as assess whether noninvasive techniques (transcranial Doppler, tympanic membrane displacement, optic nerve sheath diameter, CT scan/MRI and fundoscopy) can be used as reliable alternatives to the invasive techniques (ventriculostomy and microtransducers). Ventriculostomy is considered the gold standard in terms of accurate measurement of pressure, although microtransducers generally are just as accurate. Both invasive techniques are associated with a minor risk of complications such as hemorrhage and infection. Furthermore, zero drift is a problem with selected microtransducers. The non-invasive techniques are without the invasive methods' risk of complication, but fail to measure ICP accurately enough to be used as routine alternatives to invasive measurement. We conclude that invasive measurement is currently the only option for accurate measurement of ICP. PMID:22720148

  5. Spectrophotometric system to develop a non-invasive method for monitoring of posidonia oceanica meadows

    NASA Astrophysics Data System (ADS)

    Menesatti, P.; Urbani, G.; Dolce, T.

    2007-09-01

    Posidonia oceanica (L.) is an endemic phanerogam of the Mediterranean Sea. It lives between 0.2 and 40 m depth and make up extensive meadows that play a fundamental role in the marine coast ecosystem. Near the coasts at higher anthropic pressure, Posidonia meadows present both quality and quantity damages (regression) due to the mechanical operations on the seabed (anchoring, drag netting, pipe lines) and the sea pollution. Nowadays, the seagrass regression is monitored by different systems: aereophotografic, side scan sonar, underwater television camera, direct underwater visual inspection. Scientific community is looking for to develop monitoring systems more reliable, rapid and non invasive. Aim of this study is to evaluate the application of a new spectrophotometric imaging system based on the acquisition of reflectance spectral images with a good optical (250 Kpixels) and spectral resolution (spectral range 400-970 nm, a total of 115 single wavelength, 5 nm step each one). First trials were made on Posidonia's leafs to evaluate the system capacity to recognize spectral differences between samples picked up at two different depths (0.3 - 4 m). High discrimination percentage (90%) were found between leaf samples as function of the different depths, analyzing the spectral data by Partial Least Squares model. Forward activities will stress the system capability also to evaluate different phenol concentrations on Posidonia leaves, an important index of physiologic vegetal damage, through direct underwater spectrophotometric monitoring.

  6. Non-Invasive, Simultaneous Quantification of Vascular Oxygenation and Glucose Uptake in Tissue

    PubMed Central

    Rajaram, Narasimhan; Reesor, Andrew F.; Mulvey, Christine S.; Frees, Amy E.; Ramanujam, Nirmala

    2015-01-01

    We report the development of non-invasive, fiber-based diffuse optical spectroscopy for simultaneously quantifying vascular oxygenation (SO2) and glucose uptake in solid tumors in vivo. Glucose uptake was measured using a fluorescent glucose analog, 2-[N-(7-nitrobenz-2-oxa-1,3-diaxol-4-yl)amino]-2-deoxyglucose (2-NBDG). Quantification of label-free SO2 and 2-NBDG-fluorescence-based glucose uptake 60 minutes after administration of the tracer (2-NBDG60) was performed using computational models of light-tissue interaction. This study was carried out on normal tissue and 4T1 and 4T07 murine mammary tumor xenografts in vivo. Injection of 2-NBDG did not cause a significant change in optical measurements of SO2, demonstrating its suitability as a functional reporter of tumor glucose uptake. Correction of measured 2-NBDG-fluorescence for the effects of absorption and scattering significantly improved contrast between tumor and normal tissue. The 4T1 and 4T07 tumors showed significantly decreased SO2, and 4T1 tumors demonstrated increased 2-NBDG60 compared with normal tissue (60 minutes after the administration of 2-NBDG when perfusion-mediated effects have cleared). 2-NBDG-fluorescence was found to be highly sensitive to food deprivation-induced reduction in blood glucose levels, demonstrating that this endpoint is indeed sensitive to glycolytic demand. 2-NBDG60 was also found to be linearly related to dose, underscoring the importance of calibrating for dose when comparing across animals or experiments. 4T1 tumors demonstrated an inverse relationship between 2-NBDG60 and SO2 that was consistent with the Pasteur effect, particularly when exposed to hypoxic gas breathing. Our results illustrate the potential of optical spectroscopy to provide valuable information about the metabolic status of tumors, with important implications for cancer prognosis. PMID:25635865

  7. 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

  8. Haplotype-assisted accurate non-invasive fetal whole genome recovery through maternal plasma sequencing

    PubMed Central

    2013-01-01

    Background The applications of massively parallel sequencing technology to fetal cell-free DNA (cff-DNA) have brought new insight to non-invasive prenatal diagnosis. However, most previous research based on maternal plasma sequencing has been restricted to fetal aneuploidies. To detect specific parentally inherited mutations, invasive approaches to obtain fetal DNA are the current standard in the clinic because of the experimental complexity and resource consumption of previously reported non-invasive approaches. Methods Here, we present a simple and effective non-invasive method for accurate fetal genome recovery-assisted with parental haplotypes. The parental haplotype were firstly inferred using a combination strategy of trio and unrelated individuals. Assisted with the parental haplotype, we then employed a hidden Markov model to non-invasively recover the fetal genome through maternal plasma sequencing. Results Using a sequence depth of approximately 44X against a an approximate 5.69% cff-DNA concentration, we non-invasively inferred fetal genotype and haplotype under different situations of parental heterozygosity. Our data show that 98.57%, 95.37%, and 98.45% of paternal autosome alleles, maternal autosome alleles, and maternal chromosome X in the fetal haplotypes, respectively, were recovered accurately. Additionally, we obtained efficient coverage or strong linkage of 96.65% of reported Mendelian-disorder genes and 98.90% of complex disease-associated markers. Conclusions Our method provides a useful strategy for non-invasive whole fetal genome recovery. PMID:23445748

  9. Characterization of submicron systems via optical methods.

    PubMed

    Haskell, R J

    1998-02-01

    As a means of addressing the issues of drug delivery, submicron colloidal systems have become increasingly used as pharmaceutical formulations. Accurately characterizing physical properties of the constituent particulates present in these systems is an indispensable activity. However, measuring descriptors such as particle size distribution and surface potential presents an experimental challenge. This paper describes the physical basis for a number of optically based techniques that are useful in this task. In addition, the caveats and benefits of these methods are discussed and reference is made to their use in the examination of various multiphase systems such as liposomes, nanoparticles, and emulsions.

  10. 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.

  11. 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.

  12. Terracotta polychrome sculptures examined before and after their conservation work: contributions from non-invasive in situ analytical techniques.

    PubMed

    Colombo, C; Bevilacqua, F; Brambilla, L; Conti, C; Realini, M; Striova, J; Zerbi, G

    2011-08-01

    The potential of non-invasive in situ analytical techniques such as portable Raman, portable X-ray fluorescence, portable optical microscope and fibre optics reflectance spectroscopy has been shown studying painted layers of Renaissance terracotta polychrome sculptures belonging to the statuary of Santo Sepolcro Church in Milan. The results obtained allowed pointing out the contribution of these techniques to the compositional diagnostic, providing complete information, in some cases, better than micro-destructive techniques, on the kind of pigments used on the external painted layers. Moreover, a comparison with the results obtained before the last conservation work (2009) with micro-destructive techniques allowed ascertaining the removal of the external painted layers during the conservation operations.

  13. 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)

  14. Rib-cage-movement measurements as a potential new trigger signal in non-invasive mechanical ventilation.

    PubMed

    Ivanovic, M; Petrovic, J; Miletic, M; Danicic, A; Bojovic, B; Vukcevic, M; Lazovic, B; Gluvic, Z; Hadzievski, Lj; Allsop, T; Webb, D J

    2015-08-01

    Non-invasive ventilation performed through an oronasal mask is a standard in clinical and homecare mechanical ventilation. Besides all its advantages, inevitable leaks through the mask cause errors in the feedback information provided by the airflow sensor and, hence, patient-ventilator asynchrony with multiple negative consequences. Here we investigate a new way to provide a trigger to the ventilator. The method is based on the measurement of rib cage movement at the onset of inspiration and during breathing by fibre-optic sensors. In a series of simultaneous measurements by a long-period fibre grating sensor and pneumotachograph we provide the statistical evidence of the 200 ms lag of the pneumo with respect the fibre-optic signal. The lag is registered consistently across three independent delay metrics. Further, we discuss exceptions from this trend and identify the needed improvements to the proposed fibre-sensing scheme. PMID:26737297

  15. 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

  16. 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

  17. 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

  18. 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.

  19. Optical characterization of nonimaging focusing heliostat

    NASA Astrophysics Data System (ADS)

    Chong, Kok-Keong

    2011-10-01

    A novel nonimaging focusing heliostat consisted of many small movable element mirrors that can be dynamically maneuvered in a line-tilting manner has been proposed for the astigmatic correction in a wide range of incident angle from 0° to 70°. In this article, a comprehensive optical characterization of the new heliostat with total reflective area of 25 m2 and slant range of 25 m using ray-tracing method has been carried to analyze the performance including solar concentration ratio, ratio of aberrated-to-ideal image area, intercept efficiency and spillage loss. The optical characterization of the heliostat in the application of solar power tower system has embraced the cases of 1×1, 9×9, 11×11, 13×13, 15×15, 17×17 and 19×19 arrays of concave mirrors provided that the total reflective area remains the same. The simulated result has shown that the maximum solar concentration ratio at a high incident angle of 65° can be improved from 1.76 suns (single mirror) to 104.99 suns (9×9 mirrors), to 155.93 suns (11×11 mirrors), to 210.44 suns (13×13 mirrors), to 246.21 suns (15×15 mirrors), to 259.80 suns (17×17 mirrors) and to 264.73 suns (19×19 mirrors).

  20. 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.

  1. Sleep in the spider monkey (Ateles geoffroyi): A semi-restrictive, non-invasive, polysomnographic study.

    PubMed

    Cruz-Aguilar, Manuel Alejandro; Ayala-Guerrero, Fructuoso; Jiménez-Anguiano, Anabel; Santillán-Doherty, Ana María; García-Orduña, Francisco; Velázquez-Moctezuma, Javier

    2015-02-01

    The normal sleep patterns of the spider monkey (Ateles geoffroyi) have not been described yet. The objective of this study was to characterize the electrophysiological patterns, sleeping postures, and sleep-wake cycle in semi-restricted spider monkeys. Continuous 24-hr polysomnographic (PSG) recordings, involving simultaneous recording of non-invasive electroencephalographic (EEG), electro-oculographic (EOG), and electromyographic (EMG) activities, were carried out in captive monkeys living in outdoor rainforest enclosures. Electrode placement was done according to the human international 10-20 system. Specific behaviors displayed by monkeys during the sleep-wake cycles were correlated with the PSG recordings. The nycthemeral distribution of the sleep-wake cycle was also calculated. The results show that electrophysiological N-REM sleep patterns in spider monkeys are similar to those observed in other primates, including human beings. Furthermore, a vertical semi-fetal posture was observed during N-REM and REM sleep phases. The amount of nocturnal sleep was significantly higher than that of the diurnal period, showing that the spider monkey is a diurnal primate. An outstanding finding was the absence of muscular atonia during the spider monkey's REM sleep, which suggests that arboreal primates have developed a neuromuscular mechanism specialized for sleeping in a vertical posture.

  2. 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

  3. 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

  4. 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.

  5. Biophotonic technologies for non-invasive assessment of skin condition and blood microcirculation

    NASA Astrophysics Data System (ADS)

    Spigulis, J.

    2012-10-01

    The main results obtained at the author’s laboratory over the recent five years with respect to optical in-vivo skin assessment are reviewed. The exploited optical properties of human skin are briefly regarded, with following description of the newly developed methods and prototype devices. In particular, six non-invasive diagnostic and monitoring technologies based on skin autofluorescence photobleaching, diffuse reflectance spectrometry, multispectral skin imaging, and remission photoplethysmography have been proposed, experimentally implemented, and clinically tested. Sniegts pārskats par autora laboratorijā pēdējo piecu gadu laikā iegūtajiem in-vivo ādas optiskā novērtējuma svarīgākajiem rezultātiem. Īsumā aplūkotas dzīvas ādas optiskās īpašības, turpinājumā aprakstot jaunradītās metodes un prototipa ierīces. Piedāvātas, eksperimentāli realizētas un klīniski pārbaudītas sešas neinvazīvas diagnostikas un monitoringa tehnoloģijas, kas balstītas uz ādas autofluorescences fotoizbalēšanu, difūzās refleksijas spektrometriju, multispektrālu ādas attēlošanu un remisijas fotopletizmogrāfiju.

  6. 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

  7. Non-invasive continuous imaging of drug release from soy-based skin equivalent using wide-field interferometry

    NASA Astrophysics Data System (ADS)

    Gabai, Haniel; Baranes-Zeevi, Maya; Zilberman, Meital; Shaked, Natan T.

    2013-04-01

    We propose an off-axis interferometric imaging system as a simple and unique modality for continuous, non-contact and non-invasive wide-field imaging and characterization of drug release from its polymeric device used in biomedicine. In contrast to the current gold-standard methods in this field, usually based on chromatographic and spectroscopic techniques, our method requires no user intervention during the experiment, and only one test-tube is prepared. We experimentally demonstrate imaging and characterization of drug release from soy-based protein matrix, used as skin equivalent for wound dressing with controlled anesthetic, Bupivacaine drug release. Our preliminary results demonstrate the high potential of our method as a simple and low-cost modality for wide-field imaging and characterization of drug release from drug delivery devices.

  8. 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.

  9. Non invasive monitoring of water flow in the vadose zone: the issue of mass balance in controlled tracer injection experiments.

    NASA Astrophysics Data System (ADS)

    Cassiani, G.; Deiana, R.; Kemna, A.

    2006-12-01

    The non invasive characterization of the subsurface, with the goal of obtaining data for the calibration of flow and transport hydrologic models, has become very popular in recent years. However, the process of converting geophysical data into quantitative estimates of volumetric water content and/or solute concentrations is not straightforward, as it requires knowledge of (1) resolution and penetration characteristics of the geophysical methods (imaging characteristics); (2) suitable constitutive laws for the conversion of geophysical quantities into hydrologic quantities (petrophysics). In addition, the calibration of flow/transport models on the basis of geophysically-derived data requires that the space/time evolution of these data be summarized in terms that can be directly compared with simulation results. In the case of controlled injection experiments having a point source (e.g. a borehole section), an effective tool is the analysis of spatial moments of the injected slug. However, important issues are still unresolved, particularly with regard to the identifiability of second order spatial moments (spread) and, more disturbing, mass balance. Field experience demonstrates that it is rarely possible to "see" the total injected tracer mass by means of a non invasive method, be it cross-hole ERT or GPR, leading to errors of the order of 50%. The reasons of these limitations lie mostly in the imaging characteristics of the methods. A better understanding of these characteristics can, on the other hand, provide new tools for a more accurate calibration of flow/transport models.

  10. A non-invasive genomic diagnostic method for bladder cancer using size-based filtration and microchip electrophoresis.

    PubMed

    Deng, Yong; Yi, Linglu; Lin, Xuexia; Lin, Ling; Li, Haifang; Lin, Jin-Ming

    2015-11-01

    Bladder cancer (BC) cells spontaneously exfoliated in the urine of patients with BC. Detection of exfoliated tumor cells has clinical significance in cancer therapy because it would enable earlier non-invasive screening, diagnosis, or prognosis of BC. In this research, a method for analyzing genetic abnormalities of BC cells collected from urine samples was developed. Target BC cells were isolated by filtration. To find conditions that achieve high cell recovery, we investigated the effects of filter type, concentration of fixative, and flow rate. Cells captured on the filter membrane were completely retrieved within 15s. Selected genes for genomic analysis, mutated genes (FGFR3, TERT and HRAS) and methylated genes (ALX4, RALL3, MT1A, and RUNX3) were amplified by polymerase chain reaction (PCR), and subsequently, were identified by microchip electrophoresis (MCE). Analysis by MCE reduces the risk of contamination, sample consumption, and analysis time. Our developed approach is economical, effectively isolates cancer cells, and permits flexible molecular characterization, all of which make this approach a promising method for non-invasive BC detection.

  11. Design, development and experimental validation of a non-invasive device for recording respiratory events during bottle feeding.

    PubMed

    Cavaiola, C; Tamilia, E; Massaroni, C; Morbidoni, G; Schena, E; Formica, D; Taffoni, F

    2014-01-01

    In newborns, a poor coordination between sucking, swallowing and breathing may undermine the effectiveness of oral feeding and signal immaturity of Central Nervous System. The aim of this work is to develop and validate a non-invasive device for recording respiratory events of newborns during bottle feeding. The proposed device working principle is based on the convective heat exchanged between two hot bodies and the infants' breathing. The sensing elements are inserted into a duct and the gas exchanged by infants is conveyed into this duct thanks to an ad hoc designed system to be mounted on a commercial feeding bottle. Two sets of experiments have been carried out in order to investigate the discrimination threshold of the device and characterize the sensor response at oscillating flows. The effect of distance and tilt between nostrils and device, and the breathing frequency, have been investigated simulating nostrils and neonatal respiratory pattern. The device has a discrimination threshold lower than 0.5 L/min at both 10° and 20° of tilt. Distance for these two settings does not affect the threshold in the investigated range (10-20 mm). Moreover, the device is able to detect breathing events, and to discriminate the onset of expiratory phase, during a neonatal respiratory task delivered by a lung simulator. The results foster the successful application of this device to the assessment of the temporal breathing pattern of newborns during bottle feeding with a non-invasive approach. PMID:25570404

  12. Non-invasive Presymptomatic Detection of Cercospora beticola Infection and Identification of Early Metabolic Responses in Sugar Beet

    PubMed Central

    Arens, Nadja; Backhaus, Andreas; Döll, Stefanie; Fischer, Sandra; Seiffert, Udo; Mock, Hans-Peter

    2016-01-01

    Cercospora beticola is an economically significant fungal pathogen of sugar beet, and is the causative pathogen of Cercospora leaf spot. Selected host genotypes with contrasting degree of susceptibility to the disease have been exploited to characterize the patterns of metabolite responses to fungal infection, and to devise a pre-symptomatic, non-invasive method of detecting the presence of the pathogen. Sugar beet genotypes were analyzed for metabolite profiles and hyperspectral signatures. Correlation of data matrices from both approaches facilitated identification of candidates for metabolic markers. Hyperspectral imaging was highly predictive with a classification accuracy of 98.5–99.9% in detecting C. beticola. Metabolite analysis revealed metabolites altered by the host as part of a successful defense response: these were L-DOPA, 12-hydroxyjasmonic acid 12-O-β-D-glucoside, pantothenic acid, and 5-O-feruloylquinic acid. The accumulation of glucosylvitexin in the resistant cultivar suggests it acts as a constitutively produced protectant. The study establishes a proof-of-concept for an unbiased, presymptomatic and non-invasive detection system for the presence of C. beticola. The test needs to be validated with a larger set of genotypes, to be scalable to the level of a crop improvement program, aiming to speed up the selection for resistant cultivars of sugar beet. Untargeted metabolic profiling is a valuable tool to identify metabolites which correlate with hyperspectral data. PMID:27713750

  13. A non-invasive genomic diagnostic method for bladder cancer using size-based filtration and microchip electrophoresis.

    PubMed

    Deng, Yong; Yi, Linglu; Lin, Xuexia; Lin, Ling; Li, Haifang; Lin, Jin-Ming

    2015-11-01

    Bladder cancer (BC) cells spontaneously exfoliated in the urine of patients with BC. Detection of exfoliated tumor cells has clinical significance in cancer therapy because it would enable earlier non-invasive screening, diagnosis, or prognosis of BC. In this research, a method for analyzing genetic abnormalities of BC cells collected from urine samples was developed. Target BC cells were isolated by filtration. To find conditions that achieve high cell recovery, we investigated the effects of filter type, concentration of fixative, and flow rate. Cells captured on the filter membrane were completely retrieved within 15s. Selected genes for genomic analysis, mutated genes (FGFR3, TERT and HRAS) and methylated genes (ALX4, RALL3, MT1A, and RUNX3) were amplified by polymerase chain reaction (PCR), and subsequently, were identified by microchip electrophoresis (MCE). Analysis by MCE reduces the risk of contamination, sample consumption, and analysis time. Our developed approach is economical, effectively isolates cancer cells, and permits flexible molecular characterization, all of which make this approach a promising method for non-invasive BC detection. PMID:26452803

  14. 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.

  15. 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.

  16. 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.

  17. Landsat maps of Iraq: tools for non-invasive exploration

    SciTech Connect

    Gawarecki, S.L.; Perry, S.K.

    1984-04-01

    Optical analysis of Landsat imagery is a valuable preliminary step for exploration in areas where a detailed geologic base is lacking, logistics are difficult, or the political situation is insecure. Two maps of Iraq produced by such analysis elucidate structural and lithologic relations across a broad oil-producing region. The Landsat map of Iraq is divided into units based on drainage patterns, surface textures, relative resistance to erosion, and color. These units tentatively correlate to the broadly generalized geologic map of Iraq. The Landsat map clearly delineates Iraq's 3 major geotectonic zones: desert and alluvial plains, simply folded, and overthrust. The Lineament and anomaly map, derived from optically enhanced imagery, shows noncultural lineaments and 5 types of anomalies: linear, circular, structural, textural, and shade. Conjugate shear sets from lineaments oblique to the regional and local compression directions. Lineaments also reflect normal faults, tear faults, thrust fronts, structural control of wadis, and wind-direction features. The intersection of 3 or more lineaments defines a linear anomaly. Circular anomalies can be attributed to structural domes or basins, diapirs, calderas, or astroblemes. Appreciable deviations from local deformational style are considered structural anomalies. Textural anomalies are abrupt changes in texture unrelated to lithologic changes. Shade anomalies, mapped from band 5 enhancements, reflect a shade change from light to dark, usually across a lineament. Comparison of oil field locations to Landsat-mapped units, lineaments, and anomalies can indicate exploration targets for more detailed ground-based geologic and seismic investigation.

  18. 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.

  19. 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

  20. 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.

  1. Chromatic perception of non-invasive lighting of cave paintings

    NASA Astrophysics Data System (ADS)

    Zoido, Jesús; Vazquez, Daniel; Álvarez, Antonio; Bernabeu, Eusebio; García, Ángel; Herraez, Juán A.; del Egido, Marian

    2009-08-01

    This work is intended to deal with the problems which arise when illuminanting Paleolithic cave paintings. We have carried out the spectral and colorimetric characterization of some paintings located in the Murcielagos (bats) cave (Zuheros, Córdoba, Spain). From this characterization, the chromatic changes produced under different lighting conditions are analysed. The damage function is also computed for the different illuminants used. From the results obtained, it is proposed an illuminant whose spectral distribution diminishes the damage by minimizing the absorption of radiation and optimises the color perception of the paintings in this cave. The procedure followed in this study can be applied to optimise the lighting systems used when illuminating any other art work

  2. Development of Multifunctional Nanoparticles for Targeted Drug Delivery and Non-invasive Imaging of Therapeutic Effect

    PubMed Central

    Sajja, Hari Krishna; East, Michael P.; Mao, Hui; Wang, Andrew Y.; Nie, Shuming; Yang, Lily

    2011-01-01

    Nanotechnology is a multidisciplinary scientific field undergoing explosive development. Nanometer-sized particles offer novel structural, optical and electronic properties that are not attainable with individual molecules or bulk solids. Advances in nanomedicine can be made by engineering biodegradable nanoparticles such as magnetic iron oxide nanoparticles, polymers, dendrimers and liposomes that are capable of targeted delivery of both imaging agents and anticancer drugs. This leads toward the concept and possibility of personalized medicine for the potential of early detection of cancer lesions, determination of molecular signatures of the tumor by non-invasive imaging and, most importantly, molecular targeted cancer therapy. Increasing evidence suggests that the nanoparticles, whose surface contains a targeting molecule that binds to receptors highly expressed in tumor cells, can serve as cancer image contrast agents to increase sensitivity and specificity in tumor detection. In comparison with other small molecule contrast agents, the advantage of using nanoparticles is their large surface area and the possibility of surface modifications for further conjugation or encapsulation of large amounts of therapeutic agents. Targeted nanoparticles ferry large doses of therapeutic agents into malignant cells while sparing the normal healthy cells. Such multifunctional nanodevices hold the promise of significant improvement of current clinical management of cancer patients. This review explores the development of nanoparticles for enabling and improving the targeted delivery of therapeutic agents, the potential of nanomedicine, and the development of novel and more effective diagnostic and screening techniques to extend the limits of molecular diagnostics providing point-of-care diagnosis and more personalized medicine. PMID:19275541

  3. 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.

  4. Non-invasive localization of thymol accumulation in Carum copticum (Apiaceae) fruits by chemical shift selective magnetic resonance imaging.

    PubMed

    Gersbach, P V; Reddy, N

    2002-08-01

    Magnetic resonance imaging was used to localize the site of essential oil accumulation in fruit of Carum copticum L. (Apiaceae). A chemical shift method is described that utilized the spectral properties of the aromatic monoterpene thymol, the major component of the essential oil, to image thymol selectively. The presence of essential oil secretory structures in the fruit and an essential oil containing a high proportion of thymol were confirmed with optical microscopy and gas chromatography-mass spectrometry, respectively. Selective imaging of whole C. copticum fruits showed that thymol accumulation was localized to the secretory structures (canals) situated in the fruit wall. The technique was considered non-invasive as the seeds used in the imaging experiments remained intact and viable.

  5. 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

  6. 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.

  7. [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.

  8. [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

  9. Non-invasive monitoring of inorganic species in water

    SciTech Connect

    Ahmad, S.R.; Iles, A.

    1995-12-31

    Results of the UV absorption properties of nitrate in waters and the effects of potential inorganic and organic species on these properties are presented. The attenuation of the water Raman and Rayleigh back-scattered light of appropriate wavelengths by nitrate distributed along the probed water column is correlated with nitrate concentration. An analysis of the results in terms of an extended source in the water column and integrated absorption (over a certain depth) is presented. The feasibility of using a differential absorption and scattering technique utilizing water Raman and Rayleigh back scattered signals without any optical contact wit cell walls is examined, so that the problem of cell fouling in conventional absorption measurements is avoided.

  10. Towards a Wearable Non-invasive Blood Glucose Monitoring Device

    NASA Astrophysics Data System (ADS)

    Andrews, Joseph Thomas; Solanki, J.; Choudhary, Om P.; Chouksey, S.; Malvia, N.; Chaturvedi, P.; Sen, P.

    2012-05-01

    Every day, about 150 Million people worldwide face the problem of diabetic metabolic control. Both the hypo- and hyper- glycaemic conditions of patients have fatal consequences and warrant blood glucose monitoring at regular interval. Existing blood glucose monitors can be widely classified into three classes viz., invasive, minimally invasive, and noninvasive. Invasive monitoring requires small volume of blood and are inappropriate for continuous monitoring of blood glucose. Minimally invasive monitors analyze tissue fluid or extract few micro litre of blood only. Also the skin injury is minimal. On the other hand, noninvasive devices are painless and void of any skin injury. We use an indigenously developed polarization sensitive Optical Coherence Tomography to measure the blood glucose levels. Current trends and recent results with the device are discussed.

  11. 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

  12. 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

  13. [Design of Non-Invasive Blood Oxygen Measurement Based on AFE4490].

    PubMed

    Zhu, Jinsong; Wu, Shouhao; Guo, Wenxiu; Zheng, Hui; Tang, Dong

    2015-09-01

    From the perspective of portable monitoring devices,we use an analog front-end AFE4490 design a module of Non-invasive blood oxygen measurement, used to collect human pulse wave signal and peak (valley) value detection and then use the principles of non-invasive oximetry calculated oxygen saturation (SPO2). This design of noninvasive oximetry module has the characteristics of small size, low power consumption, and the results of test show that the measurement of oxygen saturation are correct. PMID:26904876

  14. [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.

  15. 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

  16. Non-Invasive Mapping of Human Trigeminal Brainstem Pathways

    PubMed Central

    Upadhyay, Jaymin; Knudsen, Jamie; Anderson, Julie; Becerra, Lino; Borsook, David

    2008-01-01

    The human trigeminal system mediates facial pain and somatosensory processing. The anatomic location of neuronal substrates and axonal pathways of the trigeminal system have previously been characterized with conventional in vitro methods. The present investigation implemented diffusion tensor imaging (DTI) and probabilistic tractography to first segment the peripheral trigeminal circuitry; trigeminal nerve branches (ophthalmic, maxillary and mandibular nerves), ganglion and nerve root. Subsequent segmentations involved the spinal trigeminal and trigeminal thalamic tracts, which respectively convey information to spinal trigeminal nuclei and ventral thalamic regions. This latter procedure also identified (1) spinal thalamic (anterolateral) system pathways (propagating pain and temperature information from the body); (2) trigeminal lemniscus (touch and face position) and 3) medial lemniscus (touch and limb position). The anatomic location of the identified pain and somatosensory pathways compared well with previous functional findings in human trigeminal system as well as the tract position in human histological cross-sections. Probabilistic tractography may be a useful method to further comprehend the functional and structural properties of trigeminal and other related systems. Application of DTI to map pain and somatosensory pathways in conjunction with a characterization of function properties of pain and somatosensory processing would further define the systematic changes that occur in trigeminal pathology. PMID:18956455

  17. 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

  18. New Imaging Methods for Non-invasive Assessment of Mechanical, Structural, and Biochemical Properties of Human Achilles Tendon: A Mini Review.

    PubMed

    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

  19. Non-invasive UWB sensing of astronauts' breathing activity.

    PubMed

    Baldi, Marco; Cerri, Graziano; Chiaraluce, Franco; Eusebi, Lorenzo; Russo, Paola

    2014-12-30

    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.

  20. 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

  1. Non-Invasive Pneumococcal Pneumonia in Portugal—Serotype Distribution and Antimicrobial Resistance

    PubMed Central

    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

  2. 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.

  3. Restoring Cognitive Functions Using Non-Invasive Brain Stimulation Techniques in Patients with Cerebellar Disorders

    PubMed Central

    Pope, Paul A.; Miall, R. Chris

    2014-01-01

    Numerous studies have highlighted the possibility of modulating the excitability of cerebro–cerebellar circuits bi-directionally using transcranial electrical brain stimulation, in a manner akin to that observed using magnetic stimulation protocols. It has been proposed that cerebellar stimulation activates Purkinje cells in the cerebellar cortex, leading to inhibition of the dentate nucleus, which exerts a tonic facilitatory drive onto motor and cognitive regions of cortex through a synaptic relay in the ventral–lateral thalamus. Some cerebellar deficits present with cognitive impairments if damage to non-motor regions of the cerebellum disrupts the coupling with cerebral cortical areas for thinking and reasoning. Indeed, white matter changes in the dentato–rubral tract correlate with cognitive assessments in patients with Friedreich ataxia, suggesting that this pathway is one component of the anatomical substrate supporting a cerebellar contribution to cognition. An understanding of the physiology of the cerebro–cerebellar pathway previously helped us to constrain our interpretation of results from two recent studies in which we showed cognitive enhancements in healthy participants during tests of arithmetic after electrical stimulation of the cerebellum, but only when task demands were high. Others studies have also shown how excitation of the prefrontal cortex can enhance performance in a variety of working memory tasks. Thus, future efforts might be guided toward neuro-enhancement in certain patient populations, using what is commonly termed “non-invasive brain stimulation” as a cognitive rehabilitation tool to modulate cerebro–cerebellar circuits, or for stimulation over the cerebral cortex to compensate for decreased cerebellar drive to this region. This article will address these possibilities with a review of the relevant literature covering ataxias and cerebellar cognitive affective disorders, which are characterized by thalamo

  4. 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

  5. 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

  6. 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.

  7. Optical characterization in annatto and commercial colorific.

    PubMed

    Dias, Vanessa M; Pilla, Viviane; Alves, Leandro P; Oliveira, Hueder P M; Munin, Egberto

    2011-01-01

    Nowadays, the synthetic dyes (as erythrosine, ponceau and tartrazina) and natural colourants (as annatto, paprika, curcuma and anthocyanin) are indispensable in the food, pharmaceutical and cosmetics applications. However, the use of natural colourant has been considered safer for human consumption then synthetic dye. For practical applications of the coloring, optical properties are important for the understanding of the characteristics of them. In this work, we presented the absorption and fluorescence spectroscopic characterizations of annatto extracts obtained from the seeds of the tropical shrub Bixa orellana L. solutions and commercial colourant. The measurements were performed in annatto extracts with acetone and chloroform in different concentrations range (3.5-52.5) μg/mL. The main carotenoids detected in annatto seeds is bixin. The numerical calculus of the absorbance spectra for cis- and trans-bixin conformation is presented. In addition, for commercial colourant, the measurements were performed for six different brands and five lots each one. Modifications in the shape of the colorific fluorescence spectra were observed and it can be an indicative of differences in the industrial methods applied for obtaining annatto pigments powders and/or the possibility of the presence of other impurities added in the commercial powders. PMID:20924658

  8. 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

  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. Non-invasive monitoring of endocrine status in laboratory primates: methods, guidelines and applications

    NASA Astrophysics Data System (ADS)

    Heistermann, M.

    2010-11-01

    During the past three decades, non-invasive methods for assessing physiological, in particular endocrine, status have revolutionized almost all areas of primatology, including behavioural ecology, reproductive biology, stress research, conservation and last but not least management of primates in captivity where the technology plays an integral role in assisting the husbandry, breeding and welfare of many species. Non-invasive endocrine methods make use of the fact that hormones circulating in blood are secreted into saliva or deposited in hair and are eliminated from the body via urinary and faecal excretion. The choice of which matrix to use for hormonal assessment depends on a range of factors, including the type of information required, the measurement techniques involved, species differences in hormone metabolism and route of excretion and the practicality of sample collection. However, although sample collection is usually relatively easy, analysing hormones from these non-invasively collected samples is not as easy as many people think, particularly not when dealing with a new species. In this respect, the importance of a careful validation of each technique is essential in order to generate meaningful and accurate results. This paper aims to provide an overview of the available non-invasive endocrine-based methodologies, their relative merits and their potential areas of application for assessing endocrine status in primates, with special reference to captive environments. In addition, general information is given about the most important aspects and caveats researchers have to be aware of when using these methodologies.

  11. A systematic literature review on the effectiveness of non-invasive therapy for cervicobrachial pain.

    PubMed

    Salt, Emma; Wright, Chris; Kelly, Sue; Dean, Allison

    2011-02-01

    Cervicobrachial pain is a common cervical spine disorder. It is frequently managed through non-invasive therapy. The objective of this systematic review was to assess effectiveness of non-invasive therapy for the management of cervicobrachial pain, in terms of pain, function and disability. Computerised searches were performed to January 2010. Studies were selected using pre-specified criteria. Methodological quality of included studies was assessed using PEDro and level of inter-reviewer agreement reported using Kappa values. Meta-analyses were conducted on pain scores for similar interventions using DerSimonian-Laird random-effects model to allow for heterogeneity. Effect sizes and 95% confidence intervals were reported. Qualitative analyses, based on Centre for Evidence Based Medicine levels of evidence, were conducted for function and disability. Eleven studies were included in the review. Interventions included general physiotherapy, cervical traction, manual therapy, exercise therapy, and behavioural change approaches. There was inconclusive evidence for the effectiveness of non-invasive management of cervicobrachial pain. Potential benefits were indicated in the provision of manual therapy and exercise and behavioural change approaches to reduce pain. General physiotherapy and traction were no more effective than comparators in reducing pain (level A evidence). Effects of non-invasive management on function and disability were mixed. Future studies should identify which sub-groups of cervicobrachial pain respond to specific interventions.

  12. Emerging technologies for non-invasive quantification of physiological oxygen transport in plants.

    PubMed

    Chaturvedi, P; Taguchi, M; Burrs, S L; Hauser, B A; Salim, W W A W; Claussen, J C; McLamore, E S

    2013-09-01

    Oxygen plays a critical role in plant metabolism, stress response/signaling, and adaptation to environmental changes (Lambers and Colmer, Plant Soil 274:7-15, 2005; Pitzschke et al., Antioxid Redox Signal 8:1757-1764, 2006; Van Breusegem et al., Plant Sci 161:405-414, 2001). Reactive oxygen species (ROS), by-products of various metabolic pathways in which oxygen is a key molecule, are produced during adaptation responses to environmental stress. While much is known about plant adaptation to stress (e.g., detoxifying enzymes, antioxidant production), the link between ROS metabolism, O2 transport, and stress response mechanisms is unknown. Thus, non-invasive technologies for measuring O2 are critical for understanding the link between physiological O2 transport and ROS signaling. New non-invasive technologies allow real-time measurement of O2 at the single cell and even organelle levels. This review briefly summarizes currently available (i.e., mainstream) technologies for measuring O2 and then introduces emerging technologies for measuring O2. Advanced techniques that provide the ability to non-invasively (i.e., non-destructively) measure O2 are highlighted. In the near future, these non-invasive sensors will facilitate novel experimentation that will allow plant physiologists to ask new hypothesis-driven research questions aimed at improving our understanding of physiological O2 transport.

  13. Factors affecting the clinical use of non-invasive prenatal testing: a mixed methods systematic review.

    PubMed

    Skirton, Heather; Patch, Christine

    2013-06-01

    Non-invasive prenatal testing has been in clinical use for a decade; however, there is evidence that this technology will be more widely applied within the next few years. Guidance is therefore required to ensure that the procedure is offered in a way that is evidence based and ethically and clinically acceptable. We conducted a systematic review of the current relevant literature to ascertain the factors that should be considered when offering non-invasive prenatal testing in a clinical setting. We undertook a systematic search of relevant databases, journals and reference lists, and from an initial list of 298 potential papers, identified 11 that were directly relevant to the study. Original data were extracted and presented in a table, and the content of all papers was analysed and presented in narrative form. Four main themes emerged: perceived attributes of the test, regulation and ethical issues, non-invasive prenatal testing in practice and economic considerations. However, there was a basic difference in the approach of actual or potential service users, who were very positive about the benefits of the technology, compared with other research participants, who were concerned with the potential moral and ethical outcomes of using this testing method. Recommendations for the appropriate use of non-invasive prenatal testing are made.

  14. 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

  15. Invasive versus Non Invasive Methods Applied to Mummy Research: Will This Controversy Ever Be Solved?

    PubMed

    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.

  16. 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...

  17. 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 ...

  18. 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...

  19. 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.

  20. 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

  1. Fast and non-invasive conductivity determination by the dielectric response of reduced graphene oxide: an electrostatic force microscopy study.

    PubMed

    Gómez-Navarro, Cristina; Guzmán-Vázquez, Francisco J; Gómez-Herrero, Julio; Saenz, Juan J; Sacha, G M

    2012-11-21

    The high dispersion found in the literature for the conductivity of Reduced Graphene Oxide (RGO) layers makes it highly desirable to develop fast and non-invasive methods for their characterization. Here we show that Electrostatic Force Microscopy (EFM) is an in situ, fast, and contactless technique to evaluate the conductivity of chemically derived graphene layers. The dielectric response of RGO flakes is observed to depend on their conductivity in the range of 0-3 S m(-1). Interestingly, we also find that for electrostatic purposes, a graphene layer is equivalent to an extremely thin dielectric layer with an effective permittivity (ε(eff)) that depends on the conductivity of the layers and spans from 5 for the insulating layers, to 2000 for the more conductive ones. We discuss how these high values of ε(eff) are a consequence of the incomplete screening of electric fields through graphene layers.

  2. A non-invasive method for the assessment of hemostasis in vivo by using dynamic light scattering

    NASA Astrophysics Data System (ADS)

    Fine, I.; Kaminsky, A.; Kuznik, B.; Shenkman, L.

    2012-02-01

    We present a new non-invasive method for assessing hemostasis in vivo. This method is based on the analysis of the movement characteristics of red blood cells (RBCs) during blood stasis condition. Stasis is intermittently induced by occlusion of arterial blood flow at the finger root. We assumed that under zero flow conditions, RBC movement is driven mostly by Brownian motion, and we characterized the RBC movement by utilizing the dynamic light scattering (DLS) technique in vivo. We found that during the stasis the RBCs diffusion coefficient in plasma decreases. We speculate that the RBC diffusion coefficient is most strongly related to endothelial and hemostatic activity. This assumption is supported by our findings that RBC movement, being expressed through the characteristics of the measured DLS signal, is correlative to the biological age and also is related to the coagulation factors. This new method can serve as a new diagnostic and research tool for the assessment of hemostasis and vascular function.

  3. In vivo imaging of enamel by reflectance confocal microscopy (RCM): non-invasive analysis of dental surface.

    PubMed

    Contaldo, Maria; Serpico, Rosario; Lucchese, Alberta

    2014-07-01

    The aim is to establish the feasibility to image in vivo microscopic dental surface by non-invasive, real-time, en face Reflectance Confocal Microscopy (RCM). Fifteen healthy volunteers referred at the Multidisciplinary Department of Medical-Surgical and Odontostomatological Specialties, Second University of Naples, Naples, Italy, were enrolled. A commercially available hand-held RCM (Vivascope(®)3000, Lucid, Rochester, NY, USA) was used to image in vivo the dental surface of the upper right and left central incisors of each volunteer. Totally, thirty vestibular surfaces of upper central incisors were imaged in vivo by RCM to preliminary image the dental surface and assess the feasibility of a more extended study on teeth. In vivo RCM was able to image the dental surface within the enamel, at a maximum depth imaging of 300 μm, with images good in quality and the capability to detect enamel structures such as enamel lamellae and enamel damages, such as unevenness and cracks. In conclusion, enamel "optical biopsy", gained by RCM imaging, revealed to be a non-invasive real-time tool valid to obtain architectural details of the dental surface with no need for extraction or processing the samples. RCM appears to be an optimum auxiliary device for investigating the architectural pattern of superficial enamel, therefore inviting further experiments aimed to define our knowledge about damages after etching treatments or bracket removal and the responsiveness to fluoride seals and the morphology of the tooth/restoration interface. Moreover, this device could also be used to detect relevant diseases like caries, or to assess surface properties to evaluate lesion activity.

  4. 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

  5. Cryo-Infrared Optical Characterization at NASA GSFC

    NASA Technical Reports Server (NTRS)

    Boucarut, Ray; Quijada, Manuel A.; Henry, Ross M.

    2004-01-01

    The development of large space infrared optical systems, such as the Next Generation Space Telescope (NGST), has increased requirements for measurement accuracy in the optical properties of materials. Many materials used as optical components in infrared optical systems, have strong temperature dependence in their optical properties. Unfortunately, data on the temperature dependence of most of these materials is sparse. In this paper, we provide a description of the capabilities existing in the Optics Branch at the Goddard Space Flight Center that enable the characterization of the refractive index and absorption coefficient changes and other optical properties in infrared materials at cryogenic temperatures. Details of the experimental apparatus, which include continuous flow liquid helium optical cryostat, and a Fourier Transform Infrared (FTIR) spectrometer are discussed.

  6. 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.

  7. 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.

  8. Potassium Sensitive Optical Nanosensors Containing Voltage Sensitive Dyes.

    PubMed

    Xie, Xiaojiang; Gutiérrez, Agustín; Trofimov, Valentin; Szilagyi, Istvan; Soldati, Thierry; Bakker, Eric

    2015-01-01

    lonophore-based ion-selective optical nanosensors have been explored for a number of years. Voltage sensitive dyes (VSDs) have been introduced into this type of sensors only very recently, forming a new class of analytical tools. Here, K(+)-sensitive nanospheres incorporating a lipophilic VSD were successfully fabricated and characterized. The nanosensors were readily delivered into the social amoeba Dictyostelium discoideum in a non-invasive manner, forming a promising new platform for intracellular ion quantification and imaging. PMID:26668937

  9. Aurora-A/STK-15 is a predictive factor for recurrent behaviour in non-invasive bladder carcinoma: a study of 128 cases of non-invasive neoplasms.

    PubMed

    Compérat, E; Camparo, P; Haus, R; Chartier-Kastler, E; Radenen, B; Richard, F; Capron, F; Paradis, V

    2007-04-01

    Aurora-A, a member of serine/threonine kinase, is implied in mitosis and centrosome maturation. Increasing levels of Aurora-A have been shown to be present in several malignancies and especially in bladder cancer. No immunohistochemical marker has shown to be able to predict the clinical outcome of patients with superficial bladder cancer, except MIB-1, as a predictive marker of relapse and progression. The aim was to investigate the expression of Aurora-A and MIB-1 in tissue micro arrays of superficial bladder cancer representative of pTa papillary urothelial neoplasm with different degrees of aggressiveness (low malignant potential [PUNLMP], non-invasive papillary urothelial carcinoma low grade [NILGC], non-invasive papillary urothelial carcinoma high grade [NIHGC] and carcinoma in situ). We analysed predictive values of both markers, their specificity and sensitivity in tumor recurrence. Aurora-A was a sensitive marker to predict tumor recurrence especially for pTa (PUNLMP, NILGC; PUNLMP p<0.001, NILGC p<0.001) with statistical significant correlation between immunohistochemical staining and clinical outcome. MIB-1 expression displayed statistical difference p=0.002 in the PUNLMP group and p=0.03 in the NILGC group. Aurora-A is a more sensitive marker than MIB-1 to predict relapse in pTa bladder neoplasias. The combination of both markers seems to have a very powerful predictive value of recurrence (p<0.001).

  10. 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.

  11. Non-invasive assessment of hemodynamics: a comparative analysis of fingertip pulse contour analysis and impedance cardiography

    PubMed Central

    Sauder, Katherine A.; Pokorney, Paige E.; McCrea, Cindy E.; Ulbrecht, Jan S.; Kris-Etherton, Penny M.; West, Sheila G.

    2015-01-01

    Objective Systemic hemodynamic assessment is useful for characterizing the underlying physiology of hypertension, selecting individualized treatment approaches, and understanding the underlying mechanisms of action of interventions. Invasive methods are not suitable for routine clinic or research use, and non-invasive methods such as impedance cardiography have technical and practical limitations. Fingertip pulse contour analysis measured with the Nexfin device is a novel alternative for non-invasive assessment of blood pressure and hemodynamics. While both impedance cardiography and the Nexfin have been validated against invasive methods, the extent to which they correlate with each other is unknown. This study is a comparative analysis of data simultaneously obtained with impedance cardiography and the Nexfin device. Methods As part of a larger clinical trial, 13 adults with type 2 diabetes completed cardiovascular reactivity testing on three occasions: at study baseline and after two 4-week dietary treatment periods. Blood pressure, hemodynamics, and heart rate variability were assessed at rest and during acute mental stress. Results Blood pressure, heart rate, and heart rate variability data were significantly correlated between the two devices, but hemodynamic data (stroke volume, cardiac output, total peripheral resistance) were not significantly correlated. Both techniques detected treatment-related changes in blood pressure and total peripheral resistance, but significantly differed in magnitude and/or direction of the treatment effects. Conclusions We conclude that Nexfin is not an appropriate alternative to impedance cardiography for measurement of underlying hemodynamics in psychophysiological research, but may be useful for beat-to-beat monitoring of blood pressure and heart rate variability. PMID:25815738

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. Non-invasive monitoring of oxygen delivery in acutely ill patients: new frontiers.

    PubMed

    Perel, Azriel

    2015-12-01

    Hypovolemia, anemia and hypoxemia may cause critical deterioration in the oxygen delivery (DO2). Their early detection followed by a prompt and appropriate intervention is a cornerstone in the care of critically ill patients. And yet, the remedies for these life-threatening conditions, namely fluids, blood and oxygen, have to be carefully titrated as they are all associated with severe side-effects when administered in excess. New technological developments enable us to monitor the components of DO2 in a continuous non-invasive manner via the sensor of the traditional pulse oximeter. The ability to better assess oxygenation, hemoglobin levels and fluid responsiveness continuously and simultaneously may be of great help in managing the DO2. The non-invasive nature of this technology may also extend the benefits of advanced monitoring to wider patient populations. PMID:26380992

  17. 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.

  18. Non-invasive imaging of atherosclerosis regression with magnetic resonance to guide drug development.

    PubMed

    Raggi, Paolo; Baldassarre, Damiano; Day, Simon; de Groot, Eric; Fayad, Z A

    2016-08-01

    Slowing of progression and inducing the regression of atherosclerosis with medical therapy have been shown to be associated with an extensive reduction in risk of cardiovascular events. This proof of concept was obtained with invasive angiographic studies but these are, for obvious reasons, impractical for sequential investigations. Non-invasive imaging has henceforth replaced the more cumbersome invasive studies and has proven extremely valuable in numerous occasions. Because of excellent reproducibility and no radiation exposure, magnetic resonance imaging (MRI) has become the non-invasive method of choice to assess the efficacy of anti-atherosclerotic drugs. The high accuracy of this technology is particularly helpful in rare diseases where the small number of affected patients makes the conduct of outcome-trials in large cohorts impractical. With MRI it is possible to assess the extent, as well as the composition, of atherosclerotic plaques and this further enhances the utility of this technology. PMID:27341753

  19. 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.

  20. Heating properties of non-invasive hyperthermia treatment for abdominal deep tumors by 3-D FEM.

    PubMed

    Morita, E; Kato, K; Ono, S; Shindo, Y; Tsuchiya, K; Kubo, M

    2009-01-01

    This paper discusses the heating properties of a new type of hyperthermia system composed of a re-entrant type resonant cavity applicator for deep tumors of the abdominal region. In this method, a human body is placed in the gap of two inner electrodes and is non-invasively heated with electromagnetic fields stimulated in the cavity. Here, we calculated temperature distributions of a simple human abdominal phantom model that we constructed to examine the heating properties of the developed hyperthermia system. First, the proposed heating method and a simple abdominal model to calculate the temperature distribution are presented. Second, the computer simulation results of temperature distribution by 3-D FEM are presented. From these results, it was found that the proposed simple human abdominal phantom model composed of muscle, fat and lung was useful to test the heating properties of our heating method. Our heating method was also effective to non-invasively heat abdominal deep tumors.

  1. 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

  2. [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

  3. [Non-invasive transcutaneous spinal cord stimulation facilitates locomotor activity in decerebrated and spinal cats].

    PubMed

    Musienko, P E; Bogacheva, I N; Savochin, A A; Kilimnik, V A; Gorskiĭ, O V; Nikitin, O A; Gerasimenko, Ia P

    2013-08-01

    It is known that spinal neuronal networks activated by epidural electrical stimulation (EES) can produce the stepping EMG pattern and control the locomotor behavior. At present study we showed that non-invasive transcutaneous electrical spinal cord stimulation (tESCS) applied to the lumbar-sacral enlargement can facilitate the locomotor activity in decerebrated and spinal animals. The comparison of the motor responses evoked by EES vs tESCS showed that both methods produce the locomotor patterns with close properties and similar reflex mechanisms. The data obtained suggest that tESCS is an efficient approach for investigation of the locomotor control in acute and chronic experiments as well as facilitates of the locomotor abilities after spinal cord injury. Taking to account the non-invasivity and easement of tESCS, this approach could be further implemented in clinical practice for rehabilitation of the patient with spinal cord injury.

  4. Alu methylation serves as a biomarker for non-invasive diagnosis of glioma

    PubMed Central

    Zuo, Hao; Zhao, Longxiang; Huang, Chuanjun; Liu, Xiaojiang; Hou, Shiqiang; Qi, Jing; Shi, Wei

    2016-01-01

    Current techniques for diagnosing glioma are invasive and do not accurately predict prognosis. We developed a novel, non-invasive liquid chip assay to diagnose glioma and predict prognosis. Using this method, we determined the methylation state of the Alu element in cell-free DNA extracted from the serum of 109 glioma patients. Controls included 56 patients with benign intracranial tumors and 50 healthy subjects. Matched tumor tissues were processed for 36 patients. The cfDNA from glioma patients showed lower levels of Alu methylation than the controls (P<0.01). Alu methylation was also lower in high-grade than low-grade gliomas (P<0.01), indicating that Alu methylation correlates negatively with disease severity. Moreover, Alu methylation correlated positively with survival (P<0.01). These findings suggest high-throughput liquid chip could serve as a non-invasive diagnostic assay for glioma. PMID:27028997

  5. A non-invasive method of qualitative and quantitative measurement of drugs.

    PubMed

    Westerman, S T; Gilbert, L M

    1981-09-01

    Methods for quick qualitative and quantitative evaluation of drug intake are needed, especially during emergency situations such as drug overdose and alcohol intoxication. The electronystagmograph was used in an attempt to develop a non-invasive method for identification of drug intake, and to study the effects of alcohol and other drugs on the vestibular system. Results of the study reveal that alcohol, diazepam, opiates, barbiturates, cocaine, marijuana, and hallucinogenic drugs produce a characteristic printout pattern which can be evaluated qualitatively. This method is a practical, non-invasive, objective procedure that provides rapid assessment of quality of drug intake. Its potential uses are extensive, including such possibilities as evaluation of drug intake in emergency drug overdose situations, monitoring anesthesia during surgery, evaluating drug intake in women about to deliver, (as well as the effects on the newborn), and determining whether or not persons who are being tested on a polygraph are under the influence of drugs.

  6. Prognostic value of non-invasive stress testing for coronary artery disease in obese patients.

    PubMed

    Bigvava, Tamar; Zamani, Seyedeh Mahsa; Pieske-Kraigher, Elisabeth; Gebker, Rolf; Pieske, Burkert; Kelle, Sebastian

    2015-12-01

    Detecting coronary artery disease (CAD) in obese patients remains a challenge but can have substantial prognostic implications for this patient group. Until now, sufficient data was not available on which to base the selection of the imaging modality in obese patients. The decision on which imaging modality to use should therefore follow the general guidelines. In this article, the authors discuss the prognostic value of the different non-invasive stress testing methods for CAD in obese patients.

  7. Non-invasive electric current stimulation for restoration of vision after unilateral occipital stroke.

    PubMed

    Gall, Carolin; Silvennoinen, Katri; Granata, Giuseppe; de Rossi, Francesca; Vecchio, Fabrizio; Brösel, Doreen; Bola, Michał; Sailer, Michael; Waleszczyk, Wioletta J; Rossini, Paolo M; Tatlisumak, Turgut; Sabel, Bernhard A

    2015-07-01

    Occipital stroke often leads to visual field loss, for which no effective treatment exists. Little is known about the potential of non-invasive electric current stimulation to ameliorate visual functions in patients suffering from unilateral occipital stroke. One reason is the traditional thinking that visual field loss after brain lesions is permanent. Since evidence is available documenting vision restoration by means of vision training or non-invasive electric current stimulation future studies should also consider investigating recovery processes after visual cortical strokes. Here, protocols of repetitive transorbital alternating current stimulation (rtACS) and transcranial direct current stimulation (tDCS) are presented and the European consortium for restoration of vision (REVIS) is introduced. Within the consortium different stimulation approaches will be applied to patients with unilateral occipital strokes resulting in homonymous hemianopic visual field defects. The aim of the study is to evaluate effects of current stimulation of the brain on vision parameters, vision-related quality of life, and physiological parameters that allow concluding about the mechanisms of vision restoration. These include EEG-spectra and coherence measures, and visual evoked potentials. The design of stimulation protocols involves an appropriate sham-stimulation condition and sufficient follow-up periods to test whether the effects are stable. This is the first application of non-invasive current stimulation for vision rehabilitation in stroke-related visual field deficits. Positive results of the trials could have far-reaching implications for clinical practice. The ability of non-invasive electrical current brain stimulation to modulate the activity of neuronal networks may have implications for stroke rehabilitation also in the visual domain.

  8. 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

  9. [Isolated left ventricular muscular diverticulum in an adult. Value of non-invasive examinations].

    PubMed

    Holeman, A; Bellorini, M; Lefevre, T; Lévy, M; Loiret, J; Huerta, F; Thébault, B; Funck, F

    1997-10-01

    The authors report a case of ventriculum in a 45 year old women investigated for chest pain. This was a congenital muscular left ventricular diverticulum confirmed by a complete imaging series including echocardiography, magnetic resonance imaging, angio-scintigraphy and conventional angiography. This diverticulum was unusual due to the fact that there was no associated congenital disease and that it was discovered in an adult. The authors review the literature and discuss the value of non-invasive imaging procedures.

  10. 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

  11. Non invasive indexes for the assessment of patients with non-alcoholic fatty liver disease.

    PubMed

    Petta, Salvatore; Handberg, Aase; Craxì, Antonio

    2013-01-01

    Nonalcoholic fatty liver disease (NAFLD) affects about 20%-30% of the general population, and its clinical relevance arises from the fact that 20%-30% of these subjects develop non-alcoholic steatohepatitis (NASH), a condition at risk of cirrhosis progression. In addition NAFLD, and in particular NASH patients, are also at high risk of cardiovascular alterations, suffering overall from an increased liver and no liver-related events of risk and death. At the moment liver biopsy is the gold standard for a correct evaluation of NASH and fibrosis among NAFLD patients. However, the high and increasing prevalence of NAFLD has triggered an intensive search for alternative and non-invasive methods for evaluating disease severity. Specifically we can distinguish two main groups of non-invasive methodologies, namely 'serum markers' that use clinical and/or biochemical variables, and methodologies derived from elaboration of parameters arising from liver imaging techniques. All these tools showed encouraging results, even though their utility in clinical practice in the individual patients is still under debate. Therefore further efforts are needed in order to generate non-invasive algorithms that correctly assess liver damage in NAFLD patients. In particular, it should be interesting to perform gender-specific analysis, by combining old and new tools, with the aim to generate more accurate scores. Finally we think that non-invasive scores should not only be able to correctly classify the severity of liver disease in NAFLD patients, but also predict liver and non-liver related morbidity and mortality, further acting as time-dependent markers of liver and systemic disease activity. This review summarizes the present knowledge on noninvasive diagnosis in NAFLD patients, and suggest future directions for this complex research area. PMID:23394090

  12. 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.

  13. 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

  14. 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

  15. Non-invasive electric current stimulation for restoration of vision after unilateral occipital stroke.

    PubMed

    Gall, Carolin; Silvennoinen, Katri; Granata, Giuseppe; de Rossi, Francesca; Vecchio, Fabrizio; Brösel, Doreen; Bola, Michał; Sailer, Michael; Waleszczyk, Wioletta J; Rossini, Paolo M; Tatlisumak, Turgut; Sabel, Bernhard A

    2015-07-01

    Occipital stroke often leads to visual field loss, for which no effective treatment exists. Little is known about the potential of non-invasive electric current stimulation to ameliorate visual functions in patients suffering from unilateral occipital stroke. One reason is the traditional thinking that visual field loss after brain lesions is permanent. Since evidence is available documenting vision restoration by means of vision training or non-invasive electric current stimulation future studies should also consider investigating recovery processes after visual cortical strokes. Here, protocols of repetitive transorbital alternating current stimulation (rtACS) and transcranial direct current stimulation (tDCS) are presented and the European consortium for restoration of vision (REVIS) is introduced. Within the consortium different stimulation approaches will be applied to patients with unilateral occipital strokes resulting in homonymous hemianopic visual field defects. The aim of the study is to evaluate effects of current stimulation of the brain on vision parameters, vision-related quality of life, and physiological parameters that allow concluding about the mechanisms of vision restoration. These include EEG-spectra and coherence measures, and visual evoked potentials. The design of stimulation protocols involves an appropriate sham-stimulation condition and sufficient follow-up periods to test whether the effects are stable. This is the first application of non-invasive current stimulation for vision rehabilitation in stroke-related visual field deficits. Positive results of the trials could have far-reaching implications for clinical practice. The ability of non-invasive electrical current brain stimulation to modulate the activity of neuronal networks may have implications for stroke rehabilitation also in the visual domain. PMID:26072125

  16. 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

  17. 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

  18. Non-invasive, energy-based assessment of patient-specific material properties of arterial tissue.

    PubMed

    Smoljkić, M; Vander Sloten, J; Segers, P; Famaey, N

    2015-10-01

    The mechanical properties of human biological tissue vary greatly. The determination of arterial material properties should be based on experimental data, i.e. diameter, length, intramural pressure, axial force and stress-free geometry. Currently, clinical data provide only non-invasively measured pressure-diameter data for superficial arteries (e.g. common carotid and femoral artery). The lack of information forces us to take into account certain assumptions regarding the in situ configuration to estimate material properties in vivo. This paper proposes a new, non-invasive, energy-based approach for arterial material property estimation. This approach is compared with an approach proposed in the literature. For this purpose, a simplified finite element model of an artery was used as a mock experimental situation. This method enables exact knowledge of the actual material properties, thereby allowing a quantitative evaluation of material property estimation approaches. The results show that imposing conditions on strain energy can provide a good estimation of the material properties from the non-invasively measured pressure and diameter data.

  19. 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

  20. 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

  1. 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.

  2. 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

  3. 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.

  4. 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

  5. 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

  6. 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

  7. 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

  8. SNP-based non-invasive prenatal testing detects sex chromosome aneuploidies with high accuracy

    PubMed Central

    Samango-Sprouse, Carole; Banjevic, Milena; Ryan, Allison; Sigurjonsson, Styrmir; Zimmermann, Bernhard; Hill, Matthew; Hall, Megan P.; Westemeyer, Margaret; Saucier, Jennifer; Demko, Zachary; Rabinowitz, Matthew

    2013-01-01

    Objective To develop a single nucleotide polymorphism- and informatics-based non-invasive prenatal test that detects sex chromosome aneuploidies early in pregnancy. Methods Fifteen aneuploid samples, including thirteen 45,X, two 47,XXY, and one 47,XYY, along with 185 euploid controls, were analyzed. Cell-free DNA was isolated from maternal plasma, amplified in a single multiplex PCR assay that targeted 19,488 polymorphic loci covering chromosomes 13, 18, 21, X, and Y, and sequenced. Sequencing results were analyzed using a Bayesian-based maximum likelihood statistical method to determine copy number of interrogated chromosomes, calculating sample-specific accuracies. Results Of the samples that passed a stringent quality control metric (93%), the algorithm correctly identified copy number at all five chromosomes in all 187 samples, for 934/935 correct calls as early as 9.4 weeks of gestation. We detected 45,X with 91.7% sensitivity (CI: 61.5-99.8%) and 100% specificity (CI: 97.9-100%), and 47,XXY and 47,XYY. The average calculated accuracy was 99.78%. Conclusion This method non-invasively detected 45,X, 47,XXY, and 47,XYY fetuses from cfDNA isolated from maternal plasma with high calculated accuracies, and thus offers a non-invasive method with the potential to function as a routine screen allowing for early prenatal detection of rarely diagnosed yet commonly occurring sex aneuploidies. PMID:23712453

  9. 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

  10. 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

  11. Markers for the non-invasive diagnosis of mesothelioma: a systematic review

    PubMed Central

    van der Bij, S; Schaake, E; Koffijberg, H; Burgers, J A; de Mol, B A J M; Moons, K G M

    2011-01-01

    Background: Numerous markers have been evaluated to facilitate the non-invasive diagnostic work-up of mesothelioma. The purpose of this study was to conduct a structured review of the diagnostic performance of non-invasive marker tests for the detection of mesothelioma in patients with suspected mesothelioma. Methods: Studies on the diagnostic accuracy of serum and cytological markers published till 31 December 2009, available in either PUBMED or Embase, to detect or exclude the presence of mesothelioma were extracted. Study quality was assessed with use of the Quadas criteria. Results: In total, 82 articles were included in this systemic review. Overall, quality of the incorporated studies to address our objective was poor. The most frequently studied immunohistochemical markers for cytological analysis were EMA, Ber-Ep4, CEA, and calretinin. The most frequently investigated serum marker was soluble mesothelin-related protein (SMRP). The markers CEA, Ber-EP4, and calretinin were most valuable in discriminating mesothelioma from other malignant diseases. Markers EMA and SMRP were most valuable in discriminating mesothelioma from non-malignant diseases. No marker performed well in discriminating between mesothelioma and all other diseases. Conclusion: Currently, there is only limited evidence to properly assess the value of non-invasive marker tests in the diagnosis of mesothelioma. Studies were of limited value to address our objective and results showed considerable unexplained study heterogeneity. PMID:21448170

  12. 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

  13. 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.

  14. Promoting social plasticity in developmental disorders with non-invasive brain stimulation techniques.

    PubMed

    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

  15. 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

  16. Parametric and scattering characterization of PDMS membranes for optical applications

    NASA Astrophysics Data System (ADS)

    Santiago-Alvarado, A.; Vazquez Montiel, S.; Munoz-Lopez, J.; Castro-Ramos, J.; Delgado Atencio, J. A.

    2009-08-01

    Today elastic membranes are being used more frequent as optical surfaces in the science or in the industry. This due to the advantages that they display in their handling and in their cost of production. These characteristics make them ideals to apply them in micro-optical components and Tunable Focus Liquid Filled Length Lens (TFLFLL). In order to know if a membrane of PDMS (PDMS Sylgard 184) is feasible for a specific application within the field of the optics, it is necessary to know its mechanical, optical and chemical properties. In this work the parametric membrane characterization is reported for an optical application. An important factor in the performance of these membranes is related with their scattering factor that is produced due to the roughness and impurities (micro-bubbles or dust particles). These membranes are used as refractive surface in TFLFLL. Experimental results of the characterization process and device performance are presented.

  17. 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.

  18. 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

  19. 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.

  20. 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

  1. (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.

  2. Dielectric characterization of a nonlinear optical material.

    PubMed

    Lunkenheimer, P; Krohns, S; Gemander, F; Schmahl, W W; Loidl, A

    2014-01-01

    Batisite was reported to be a nonlinear optical material showing second harmonic generation. Using dielectric spectroscopy and polarization measurements, we provide a thorough investigation of the dielectric and charge-transport properties of this material. Batisite shows the typical characteristics of a linear lossy dielectric. No evidence for ferro- or antiferroelectric polarization is found. As the second-harmonic generation observed in batisite points to a non-centrosymmetric structure, this material is piezoelectric, but most likely not ferroelectric. In addition, we found evidence for hopping charge transport of localized charge carriers and a relaxational process at low temperatures. PMID:25109553

  3. 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.

  4. Optical Metamaterials: Design, Characterization and Applications

    ERIC Educational Resources Information Center

    Chaturvedi, Pratik

    2009-01-01

    Artificially engineered metamaterials have emerged with properties and functionalities previously unattainable in natural materials. The scientific breakthroughs made in this new class of electromagnetic materials are closely linked with progress in developing physics-driven design, novel fabrication and characterization methods. The intricate…

  5. Optical fiber sensors for materials and structures characterization

    NASA Technical Reports Server (NTRS)

    Lindner, D. K.; Claus, R. O.

    1991-01-01

    The final technical report on Optical Fiber Sensors for Materials and Structures Characterization, covering the period August 1990 through August 1991 is presented. Research programs in the following technical areas are described; sapphire optical fiber sensors; vibration analysis using two-mode elliptical core fibers and sensors; extrinsic Fabry-Perot interferometer development; and coatings for fluorescent-based sensor. Research progress in each of these areas was substantial, as evidenced by the technical publications which are included as appendices.

  6. 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.

  7. 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.

  8. Raman Microscopy for Non-Invasive Imaging of Pharmaceutical Nanocarriers: Intracellular Distribution of Cationic Liposomes of Different Composition

    PubMed Central

    Sawant, R. R.; Miljkovic, M.; Quintero, L.; Diem, M.

    2012-01-01

    Nanotechnology is playing an increasing role in targeted drug delivery into pathological tissues. Drug-loaded pharmaceutical nanocarriers can be delivered into diseased sites by passive targeting (spontaneous accumulation of nanocarriers in the areas with affected vasculature) or by active targeting (via site-specific ligands attached to the surface of drug-loaded nanocarriers). Subsequent level of targeting requires cellular internalization of nanocarriers and their specific association with certain individual cell organelles. The control over intracellular distribution of pharmaceutical nanocarriers requires effective and non-invasive methods of their visualization inside cells. In an attempt to enhance cellular internalization of pharmaceutical nanocarriers and their association with mitochondria specifically, we have prepared three types of cationic liposomes and investigated their intracellular distribution. The analysis was performed using Raman microspectroscopy in combination with optical microscopy, in order to provide morphological information as well as biochemical signatures of the sample. It was demonstrated that the Raman microscopy allows to evaluate the extent of mitochondrial association depending on the liposome composition. PMID:22376068

  9. 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.

  10. Intrapartum ST segment analyses (STAN) using simultaneous invasive and non-invasive fetal electrocardiography: a report of 6 cases.

    PubMed

    Reinhard, J; Hayes-Gill, B; Yuan, J; Schiermeier, S; Louwen, F

    2014-06-01

    The objective of this study was to analyze ST segment analyses (STAN) using simultaneous traditional - gold standard invasive (fetal scalp electrode) and newly available non-invasive abdominal fetal electrocardiography (fECG) during delivery.This was a prospective observational study of non-invasive fetal ECG using 5 abdominally sited electrodes (Monica AN24) against the traditional fetal scalp electrodes (STAN S31) on 6 patients. Data were analyzed when the STAN S31 found the baseline and when there was a baseline rise.Successful fECG signal acquisition was achieved in 6/6 (100%) patients. Using the non-invasive fECG, P and QRS waves were seen in all cases, and T waves in 3/6 (50%). ST segment analysis analysis was possible in 6/6 (100%) and 3/6 (50%) using invasive and non-invasive fECG, respectively.This study demonstrates that ST segment analysis is feasible using invasive and non-invasive fECG. Further studies are warranted to confirm the preliminary results and improve ECG morphology of non-invasive fECG.

  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.

  13. 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

  14. 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

  15. Prediction of human core body temperature using non-invasive measurement methods.

    PubMed

    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.

  16. 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

  17. 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.

  18. Comparison between invasive and non-invasive blood pressure in young, middle and old age.

    PubMed

    Liu, Bing; Li, Qiao; Qiu, Peng

    2016-06-01

    We aimed to compare simultaneous invasive and non-invasive blood pressure (IBP and NIBP) measurements in young, middle and old age using the data from the Multiparameter Intelligent Monitoring in Intensive Care II (MIMIC II) database. In total, 23,679 blood pressure measurements were extracted from 742 patients, divided into three groups of young, middle and old age. IBP-NIBP differences in systolic/diastolic blood pressure (SBP/DBP) were 0.1 ± 16.5 mmHg/11.0 ± 12.2 mmHg in young age, -2.9 ± 19.8 mmHg/6.9 ± 17.5 mmHg in middle age and -3.2 ± 29.3 mmHg/8.5 ± 19.8 mmHg in old age. The mean and standard deviation (SD) of invasive systolic blood pressure (ISBP)-non-invasive systolic blood pressure (NISBP) differences increased from young to middle then to old age, and the SD of invasive diastolic blood pressure (IDBP)-non-invasive diastolic blood pressure (NIDBP) differences also increased with age. In young, middle and old age, the correlation coefficients were 0.86, 0.79 and 0.53, respectively, between ISBP and NISBP, and 0.78, 0.78 and 0.41 between IDBP and NIDBP. In conclusion, IBP showed good correlation with NIBP in each age category. The agreement between IBP and NIBP measurements was influenced by age category.

  19. Optical characterization of the MALDI plume

    SciTech Connect

    Hurst, G.B.

    1995-12-31

    The development of matrix-assisted laser desorption/ionization (MALDI) by Karas, Hillenkamp et al. has brought an entire new class of large-molecule applications within the reach of mass spectrometry. However, the ionization efficiency and therefore the sensitivity of the technique could be improved if details of the ionization mechanism were understood more thoroughly. The environment in the MALDI plume may influence the ionization of the analyte, in analogy to the effect of pH on biomolecules in solution. Optical probing techniques, such as laser-induced fluorescence, allow some characteristics of the plume environment to be studied directly. This paper describes measurement of wavelength-dispersed fluorescence produced in MALDI experiments in a time-of-flight mass spectrometer (TOF-MS).

  20. Optics characterization with compact EUV spectrophotometer

    NASA Astrophysics Data System (ADS)

    Blaschke, H.; Balasa, I.; Koch, L.; Starke, K.; Ristau, D.; Wies, C.; Lebert, R.; Bayer, A.; Barkusky, F.; Mann, K.

    2008-03-01

    The development of a novel compact EUV spectrophotometer will be presented. The device is capable of measuring reflectance and transmittance spectra of medium scale EUV-optics primary in the spectral range from 12nm to 21nm. Based on a new polychromatic measurement principle, the system uses the direct irradiation of a table-top EUV-source for illuminating the sample and a broad-band spectrograph for detecting the probe and reference beam. Samples can be investigated under different angles of incidence and in respect of lateral dependencies. Typical results of reflectivity investigations of Mo/Si-mirrors and transmitting foils will be shown and compared with reference measurements of certified institutes and calculations.

  1. 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.

  2. Non-invasive estimation of dissipation from non-equilibrium fluctuations in chemical reactions.

    PubMed

    Muy, S; Kundu, A; Lacoste, D

    2013-09-28

    We show how to extract an estimate of the entropy production from a sufficiently long time series of stationary fluctuations of chemical reactions. This method, which is based on recent work on fluctuation theorems, is direct, non-invasive, does not require any knowledge about the underlying dynamics and is applicable even when only partial information is available. We apply it to simple stochastic models of chemical reactions involving a finite number of states, and for this case, we study how the estimate of dissipation is affected by the degree of coarse-graining present in the input data.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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

  8. 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

  9. 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.

  10. Classification and grading of the non-invasive urothelial neoplasms: recent advances and controversies

    PubMed Central

    Montironi, R; Lopez-Beltran, A; Mazzucchelli, R; Bostwick, D G

    2003-01-01

    The classification and grading of the non-invasive, intraepithelial neoplasms of the urothelium are based on the morphological pattern of growth—that is, papillary or flat (and endophytic)—and on their degree of architectural and cytological abnormalities. Recent advances in the morphological, molecular, and quantitative evaluation of these lesions have contributed to the refinement of the current classification and grading schemes. However, some controversies on the precise criteria and terminology, especially when the papillary lesions are concerned, are still present. PMID:12560385

  11. [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.

  12. Multiphoton excited hemoglobin fluorescence and third harmonic generation for non-invasive microscopy of stored blood

    PubMed Central

    Saytashev, Ilyas; Glenn, Rachel; Murashova, Gabrielle A.; Osseiran, Sam; Spence, Dana; Evans, Conor L.; Dantus, Marcos

    2016-01-01

    Red blood cells (RBC) in two-photon excited fluorescence (TPEF) microscopy usually appear as dark disks because of their low fluorescent signal. Here we use 15fs 800nm pulses for TPEF, 45fs 1060nm pulses for three-photon excited fluorescence, and third harmonic generation (THG) imaging. We find sufficient fluorescent signal that we attribute to hemoglobin fluorescence after comparing time and wavelength resolved spectra of other expected RBC endogenous fluorophores: NADH, FAD, biliverdin, and bilirubin. We find that both TPEF and THG microscopy can be used to examine erythrocyte morphology non-invasively without breaching a blood storage bag. PMID:27699111

  13. Epigastric impedance: a non-invasive method for the assessment of gastric emptying and motility.

    PubMed Central

    McClelland, G R; Sutton, J A

    1985-01-01

    The impedance of the epigastrium to a 4 mA, 100 KHz AC current increases while liquids of low electrical conductivity are being drunk. Logically, the decline which follows occurs as the liquid leaves the stomach. This impedance measurement of gastric emptying proved comparable with the dye dilution method. In a placebo controlled trial the impedance method recorded significantly faster gastric emptying rates after metoclopramide. The impedance trace contains regular activity in the 2-4 cycle/min range consistent with gastric contractions. This non-invasive and technically simple method may thus provide a measure of simultaneous gastric emptying rates and motility. PMID:3891533

  14. 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.

  15. Multiphoton excited hemoglobin fluorescence and third harmonic generation for non-invasive microscopy of stored blood

    PubMed Central

    Saytashev, Ilyas; Glenn, Rachel; Murashova, Gabrielle A.; Osseiran, Sam; Spence, Dana; Evans, Conor L.; Dantus, Marcos

    2016-01-01

    Red blood cells (RBC) in two-photon excited fluorescence (TPEF) microscopy usually appear as dark disks because of their low fluorescent signal. Here we use 15fs 800nm pulses for TPEF, 45fs 1060nm pulses for three-photon excited fluorescence, and third harmonic generation (THG) imaging. We find sufficient fluorescent signal that we attribute to hemoglobin fluorescence after comparing time and wavelength resolved spectra of other expected RBC endogenous fluorophores: NADH, FAD, biliverdin, and bilirubin. We find that both TPEF and THG microscopy can be used to examine erythrocyte morphology non-invasively without breaching a blood storage bag.

  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. 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.

  18. 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.

  19. [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

  20. Non-invasive neuromagnetic monitoring of nerve and muscle injury currents.

    PubMed

    Curio, G; Erné, S N; Burghoff, M; Wolff, K D; Pilz, A

    1993-06-01

    Structural damage inflicted on membranes of excitable cells may evoke quasi-DC injury currents driven by the transmembrane resting potential gradient. In contrast to the usually invasive electrophysiological approaches, superconducting quantum interference devices (SQUIDs) measure the concomitant weak biomagnetic fields non-invasively as is shown here for acutely excised rat nerves or muscles. Analysis of the field distributions showed slowly decaying equivalent current dipole moments in the nanoampmeter range as generated by microamp nerve injury currents extending intra-axonally over millimeter distances. The geometric and kinetic parameters of this experimental design may allow in vivo recordings in human patients.

  1. 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

  2. Optical characterization of sputtered carbon films

    SciTech Connect

    Ager, J.W. III.

    1992-05-01

    Spattered carbon films are widely used as protective overcoats for thin film disk media. Raman spectroscopy is nondestructive and relatively rapid and is well suited for the characterization of carbon films. Specific features in the Raman spectra are empirically correlated with the rates of specific types of mechanical wear for both hydrogenated and unhydrogenated films. This observation is interpreted in terms of a random covalent network, in which the mechanical performance of the film is determined by the nature of the bonding that links sp{sup 2}-bonded domains.

  3. Characterization of periodic cavitation in optical tweezers.

    PubMed

    Carmona-Sosa, Viridiana; Alba-Arroyo, José Ernesto; Quinto-Su, Pedro A

    2016-03-10

    Microscopic vapor explosions or cavitation bubbles can be generated repeatedly in optical tweezers with a microparticle that partially absorbs at the trapping laser wavelength. In this work we measure the size distribution and the production rate of cavitation bubbles for microparticles with a diameter of 3 μm using high-speed video recording and a fast photodiode. We find that there is a lower bound for the maximum bubble radius R(max)∼2  μm which can be explained in terms of the microparticle size. More than 94% of the measured R(max) are in the range between 2 and 6 μm, while the same percentage of the measured individual frequencies f(i) or production rates are between 10 and 200 Hz. The photodiode signal yields an upper bound for the lifetime of the bubbles, which is at most twice the value predicted by the Rayleigh equation. We also report empirical relations between R(max), f(i), and the bubble lifetimes. PMID:26974779

  4. Non-invasive in vivo infrared laser spectroscopy to analyse endogenous oxy-haemoglobin, deoxy-haemoglobin, and blood volume in the rat CNS.

    PubMed

    Crespi, Francesco; Bandera, Andrea; Donini, Maurizio; Heidbreder, Christian; Rovati, Luigi

    2005-06-30

    Oxy-haemoglobin (HbO2) and deoxy-haemoglobin (Hb) are chromophores present in biological tissues. Near infrared spectroscopy (NIRS) is a non-invasive methodology based on the low extinction coefficient of tissue in the near infrared region. NIRS can be used to measure changes in the concentration of these chromophores, i.e., haemoglobin, in muscular tissue. In the present work, NIRS has been used for the non-invasive monitoring of HbO2, Hb, and blood volume (V: representing total haemoglobin, i.e., HbO2+Hb) in vivo in the whole rat brain. This has been performed by means of prototype instrumentation based on optic fibre probes placed in contact with the head of anaesthetised rats held in a stereotaxic frame. A preliminary test of the instrument has been performed on human muscle, i.e., lateral gastrocnemius, in order to evaluate the ability of the instrument to detect oxygenation changes. Afterwards, the effects of pharmacological treatments, such as systemic amphetamine and nicotine treatments on the CNS have been detected.

  5. Frontal Non-Invasive Neurostimulation Modulates Antisaccade Preparation in Non-Human Primates

    PubMed Central

    Valero-Cabre, Antoni; Wattiez, Nicolas; Monfort, Morgane; François, Chantal; Rivaud-Péchoux, Sophie; Gaymard, Bertrand; Pouget, Pierre

    2012-01-01

    A combination of oculometric measurements, invasive electrophysiological recordings and microstimulation have proven instrumental to study the role of the Frontal Eye Field (FEF) in saccadic activity. We hereby gauged the ability of a non-invasive neurostimulation technology, Transcranial Magnetic Stimulation (TMS), to causally interfere with frontal activity in two macaque rhesus monkeys trained to perform a saccadic antisaccade task. We show that online single pulse TMS significantly modulated antisaccade latencies. Such effects proved dependent on TMS site (effects on FEF but not on an actively stimulated control site), TMS modality (present under active but not sham TMS on the FEF area), TMS intensity (intensities of at least 40% of the TMS machine maximal output required), TMS timing (more robust for pulses delivered at 150 ms than at 100 post target onset) and visual hemifield (relative latency decreases mainly for ipsilateral AS). Our results demonstrate the feasibility of using TMS to causally modulate antisaccade-associated computations in the non-human primate brain and support the use of this approach in monkeys to study brain function and its non-invasive neuromodulation for exploratory and therapeutic purposes. PMID:22701691

  6. Anaphylaxis Imaging: Non-Invasive Measurement of Surface Body Temperature and Physical Activity in Small Animals.

    PubMed

    Manzano-Szalai, Krisztina; Pali-Schöll, Isabella; Krishnamurthy, Durga; Stremnitzer, Caroline; Flaschberger, Ingo; Jensen-Jarolim, Erika

    2016-01-01

    In highly sensitized patients, the encounter with a specific allergen from food, insect stings or medications may rapidly induce systemic anaphylaxis with potentially lethal symptoms. Countless animal models of anaphylaxis, most often in BALB/c mice, were established to understand the pathophysiology and to prove the safety of different treatments. The most common symptoms during anaphylactic shock are drop of body temperature and reduced physical activity. To refine, improve and objectify the currently applied manual monitoring methods, we developed an imaging method for the automated, non-invasive measurement of the whole-body surface temperature and, at the same time, of the horizontal and vertical movement activity of small animals. We tested the anaphylaxis imaging in three in vivo allergy mouse models for i) milk allergy, ii) peanut allergy and iii) egg allergy. These proof-of-principle experiments suggest that the imaging technology represents a reliable non-invasive method for the objective monitoring of small animals during anaphylaxis over time. We propose that the method will be useful for monitoring diseases associated with both, changes in body temperature and in physical behaviour. PMID:26963393

  7. Non-invasive ultrasonic measurement of the elastic properties of the human abdominal aorta.

    PubMed

    Imura, T; Yamamoto, K; Kanamori, K; Mikami, T; Yasuda, H

    1986-03-01

    A new echo tracking device linked to real time ultrasonic B mode equipment was developed to measure non-invasively the elastic properties of the human abdominal aorta. Pulsatile diameter change and mean diameter of the abdominal aorta were measured in 61 subjects with this ultrasonic device. Strain and pressure-strain elastic modulus Ep were calculated from pulsatile diameter change, diameter, and pulse pressure obtained by the auscultatory method. Strain significantly decreased with age; 0.076(0.024) (mean(SD)) in group 1 (20 young adults below the age of 35 years); 0.048(0.024) in group 2 (21 middle aged subjects between the ages of 35 and 60 years); and 0.030(0.010) in group 3 (20 elderly subjects over the age of 60 years). Ep values were 0.99(0.34) X 10(5), 1.55(0.68) X 10(5), and 3.80(2.05) X 10(5) N X m-2 in groups 1, 2, and 3 respectively. Ep in group 3 was significantly higher than in groups 1 and 2. The regression equation relating Ep to age was Ep = (-0.72 + 0.058 X age) X 10(5) N X m-2 (r = 0.73). The Ep value and its age related increase agreed with the findings in postmortem arteries. The elastic properties of the abdominal aorta could, therefore, be determined non-invasively by this ultrasonic method.

  8. Development of a Portable Non-Invasive Swallowing and Respiration Assessment Device †

    PubMed Central

    Shieh, Wann-Yun; Wang, Chin-Man; Chang, Chia-Shuo

    2015-01-01

    Dysphagia is a condition that happens when a person cannot smoothly swallow food from the mouth to the stomach. It causes malnourishment in patients, or can even cause death due to aspiration pneumonia. Recently, more and more researchers have focused their attention on the importance of swallowing and respiration coordination, and the use of non-invasive assessment systems has become a hot research trend. In this study, we aimed to integrate the timing and pattern monitoring of respiration and swallowing by using a portable and non-invasive approach which can be applied at the bedside in hospitals or institutions, or in a home environment. In this approach, we use a force sensing resistor (FSR) to detect the motions of the thyroid cartilage in the pharyngeal phase. We also use the surface electromyography (sEMG) to detect the contraction of the submental muscle in the oral phase, and a nasal cannula to detect nasal airflow for respiration monitoring during the swallowing process. All signals are received and processed for swallowing event recognition. A total of 19 volunteers participated in the testing and over 57 measurements were made. The results show that the proposed approach can effectively distinguish the swallowing function in people of different ages and genders. PMID:26024414

  9. Invasive clonal plant species have a greater root-foraging plasticity than non-invasive ones.

    PubMed

    Keser, Lidewij H; Dawson, Wayne; Song, Yao-Bin; Yu, Fei-Hai; Fischer, Markus; Dong, Ming; van Kleunen, Mark

    2014-03-01

    Clonality is frequently positively correlated with plant invasiveness, but which aspects of clonality make some clonal species more invasive than others is not known. Due to their spreading growth form, clonal plants are likely to experience spatial heterogeneity in nutrient availability. Plasticity in allocation of biomass to clonal growth organs and roots may allow these plants to forage for high-nutrient patches. We investigated whether this foraging response is stronger in species that have become invasive than in species that have not. We used six confamilial pairs of native European clonal plant species differing in invasion success in the USA. We grew all species in large pots under homogeneous or heterogeneous nutrient conditions in a greenhouse, and compared their nutrient-foraging response and performance. Neither invasive nor non-invasive species showed significant foraging responses to heterogeneity in clonal growth organ biomass or in aboveground biomass of clonal offspring. Invasive species had, however, a greater positive foraging response in terms of root and belowground biomass than non-invasive species. Invasive species also produced more total biomass. Our results suggest that the ability for strong root foraging is among the characteristics promoting invasiveness in clonal plants.

  10. Diagnostic and prognostic utility of non-invasive imaging in diabetes management

    PubMed Central

    Barsanti, Cristina; Lenzarini, Francesca; Kusmic, Claudia

    2015-01-01

    Medical imaging technologies are acquiring an increasing relevance to assist clinicians in diagnosis and to guide management and therapeutic treatment of patients, thanks to their non invasive and high resolution properties. Computed tomography, magnetic resonance imaging, and ultrasonography are the most used imaging modalities to provide detailed morphological reconstructions of tissues and organs. In addition, the use of contrast dyes or radionuclide-labeled tracers permits to get functional and quantitative information about tissue physiology and metabolism in normal and disease state. In recent years, the development of multimodal and hydrid imaging techniques is coming to be the new frontier of medical imaging for the possibility to overcome limitations of single modalities and to obtain physiological and pathophysiological measurements within an accurate anatomical framework. Moreover, the employment of molecular probes, such as ligands or antibodies, allows a selective in vivo targeting of biomolecules involved in specific cellular processes, so expanding the potentialities of imaging techniques for clinical and research applications. This review is aimed to give a survey of characteristics of main diagnostic non-invasive imaging techniques. Current clinical appliances and future perspectives of imaging in the diagnostic and prognostic assessment of diabetic complications affecting different organ systems will be particularly addressed. PMID:26131322

  11. Reactivity of Dogs' Brain Oscillations to Visual Stimuli Measured with Non-Invasive Electroencephalography

    PubMed Central

    Kujala, Miiamaaria V.; Törnqvist, Heini; Somppi, Sanni; Hänninen, Laura; Krause, Christina M.; Vainio, Outi; Kujala, Jan

    2013-01-01

    Studying cognition of domestic dogs has gone through a renaissance within the last decades. However, although the behavioral studies of dogs are beginning to be common in the field of animal cognition, the neural events underlying cognition remain unknown. Here, we employed a non-invasive electroencephalography, with adhesive electrodes attached to the top of the skin, to measure brain activity of from 8 domestic dogs (Canis familiaris) while they stayed still to observe photos of dog and human faces. Spontaneous oscillatory activity of the dogs, peaking in the sensors over the parieto-occipital cortex, was suppressed statistically significantly during visual task compared with resting activity at the frequency of 15–30 Hz. Moreover, a stimulus-induced low-frequency (∼2–6 Hz) suppression locked to the stimulus onset was evident at the frontal sensors, possibly reflecting a motor rhythm guiding the exploratory eye movements. The results suggest task-related reactivity of the macroscopic oscillatory activity in the dog brain. To our knowledge, the study is the first to reveal non-invasively measured reactivity of brain electrophysiological oscillations in healthy dogs, and it has been based purely on positive operant conditional training, without the need for movement restriction or medication. PMID:23650504

  12. Non-invasive screening of cytochrome c oxidase deficiency in children using a dipstick immunocapture assay.

    PubMed

    Rodinová, M; Trefilová, E; Honzík, T; Tesařová, M; Zeman, J; Hansíková, H

    2014-01-01

    Cytochrome c oxidase (CIV) deficiency is among the most common childhood mitochondrial disorders. The diagnosis of this deficiency is complex, and muscle biopsy is used as the gold standard of diagnosis. Our aim was to minimize the patient burden and to test the use of a dipstick immunocapture assay (DIA) to determine the amount of CIV in non-invasively obtained buccal epithelial cells. Buccal smears were obtained from five children with Leigh syndrome including three children exhibiting a previously confirmed CIV deficiency in muscle and fibroblasts and two children who were clinical suspects for CIV deficiency; the smear samples were analysed using CI and CIV human protein quantity dipstick assay kits. Samples from five children of similar age and five adults were used as controls. Analysis of the controls demonstrated that only samples of buccal cells that were frozen for a maximum of 4 h after collection provide accurate results. All three patients with confirmed CIV deficiency due to mutations in the SURF1 gene exhibited significantly lower amounts of CIV than the similarly aged controls; significantly lower amounts were also observed in two new patients, for whom later molecular analysis also confirmed pathologic mutations in the SURF1 gene. We conclude that DIA is a simple, fast and sensitive method for the determination of CIV in buccal cells and is suitable for the screening of CIV deficiency in non-invasively obtained material from children who are suspected of having mitochondrial disease. PMID:25629267

  13. Modelling, verification, and calibration of a photoacoustics based continuous non-invasive blood glucose monitoring system

    NASA Astrophysics Data System (ADS)

    Pai, Praful P.; Sanki, Pradyut K.; Sarangi, Satyabrata; Banerjee, Swapna

    2015-06-01

    This paper examines the use of photoacoustic spectroscopy (PAS) at an excitation wavelength of 905 nm for making continuous non-invasive blood glucose measurements. The theoretical background of the measurement technique is verified through simulation. An apparatus is fabricated for performing photoacoustic measurements in vitro on glucose solutions and in vivo on human subjects. The amplitude of the photoacoustic signals measured from glucose solutions is observed to increase with the solution concentration, while photoacoustic amplitude obtained from in vivo measurements follows the blood glucose concentration of the subjects, indicating a direct proportionality between the two quantities. A linear calibration method is applied separately on measurements obtained from each individual in order to estimate the blood glucose concentration. The estimated glucose values are compared to reference glucose concentrations measured using a standard glucose meter. A plot of 196 measurement pairs taken over 30 normal subjects on a Clarke error grid gives a point distribution of 82.65% and 17.35% over zones A and B of the grid with a mean absolute relative deviation (MARD) of 11.78% and a mean absolute difference (MAD) of 15.27 mg/dl (0.85 mmol/l). The results obtained are better than or comparable to those obtained using photoacoustic spectroscopy based methods or other non-invasive measurement techniques available. The accuracy levels obtained are also comparable to commercially available continuous glucose monitoring systems.

  14. Trends in Nanomaterial-Based Non-Invasive Diabetes Sensing Technologies

    PubMed Central

    Makaram, Prashanth; Owens, Dawn; Aceros, Juan

    2014-01-01

    Blood glucose monitoring is considered the gold standard for diabetes diagnostics and self-monitoring. However, the underlying process is invasive and highly uncomfortable for patients. Furthermore, the process must be completed several times a day to successfully manage the disease, which greatly contributes to the massive need for non-invasive monitoring options. Human serums, such as saliva, sweat, breath, urine and tears, contain traces of glucose and are easily accessible. Therefore, they allow minimal to non-invasive glucose monitoring, making them attractive alternatives to blood measurements. Numerous developments regarding noninvasive glucose detection techniques have taken place over the years, but recently, they have gained recognition as viable alternatives, due to the advent of nanotechnology-based sensors. Such sensors are optimal for testing the amount of glucose in serums other than blood thanks to their enhanced sensitivity and selectivity ranges, in addition to their size and compatibility with electronic circuitry. These nanotechnology approaches are rapidly evolving, and new techniques are constantly emerging. Hence, this manuscript aims to review current and future nanomaterial-based technologies utilizing saliva, sweat, breath and tears as a diagnostic medium for diabetes monitoring. PMID:26852676

  15. Anaphylaxis Imaging: Non-Invasive Measurement of Surface Body Temperature and Physical Activity in Small Animals.

    PubMed

    Manzano-Szalai, Krisztina; Pali-Schöll, Isabella; Krishnamurthy, Durga; Stremnitzer, Caroline; Flaschberger, Ingo; Jensen-Jarolim, Erika

    2016-01-01

    In highly sensitized patients, the encounter with a specific allergen from food, insect stings or medications may rapidly induce systemic anaphylaxis with potentially lethal symptoms. Countless animal models of anaphylaxis, most often in BALB/c mice, were established to understand the pathophysiology and to prove the safety of different treatments. The most common symptoms during anaphylactic shock are drop of body temperature and reduced physical activity. To refine, improve and objectify the currently applied manual monitoring methods, we developed an imaging method for the automated, non-invasive measurement of the whole-body surface temperature and, at the same time, of the horizontal and vertical movement activity of small animals. We tested the anaphylaxis imaging in three in vivo allergy mouse models for i) milk allergy, ii) peanut allergy and iii) egg allergy. These proof-of-principle experiments suggest that the imaging technology represents a reliable non-invasive method for the objective monitoring of small animals during anaphylaxis over time. We propose that the method will be useful for monitoring diseases associated with both, changes in body temperature and in physical behaviour.

  16. Non-invasive spectroscopy of transfusable red blood cells stored inside sealed plastic blood-bags.

    PubMed

    Buckley, K; Atkins, C G; Chen, D; Schulze, H G; Devine, D V; Blades, M W; Turner, R F B

    2016-03-01

    After being separated from (donated) whole blood, red blood cells are suspended in specially formulated additive solutions and stored (at 4 °C) in polyvinyl chloride (PVC) blood-bags until they are needed for transfusion. With time, the prepared red cell concentrate (RCC) is known to undergo biochemical changes that lower effectiveness of the transfusion, and thus regulations are in place that limit the storage period to 42 days. At present, RCC is not subjected to analytical testing prior to transfusion. In this study, we use Spatially Offset Raman Spectroscopy (SORS) to probe, non-invasively, the biochemistry of RCC inside sealed blood-bags. The retrieved spectra compare well with conventional Raman spectra (of sampled aliquots) and are dominated by features associated with hemoglobin. In addition to the analytical demonstration that SORS can be used to retrieve RCC spectra from standard clinical blood-bags without breaking the sterility of the system, the data reveal interesting detail about the oxygenation-state of the stored cells themselves, namely that some blood-bags unexpectedly contain measurable amounts of deoxygenated hemoglobin after weeks of storage. The demonstration that chemical information can be obtained non-invasively using spectroscopy will enable new studies of RCC degeneration, and points the way to a Raman-based instrument for quality-control in a blood-bank or hospital setting.

  17. Fur: A non-invasive approach to monitor metal exposure in bats.

    PubMed

    Hernout, Béatrice V; McClean, Colin J; Arnold, Kathryn E; Walls, Michael; Baxter, Malcolm; Boxall, Alistair B A

    2016-03-01

    This paper presents a novel assessment of the use of fur as a non-invasive proxy to biomonitor metal contamination in insectivorous bats. Concentrations of metals (cadmium, copper, lead and zinc) were measured using ICP-MS in tissues (kidneys, liver, stomach and stomach content, bones and fur) obtained from 193 Pipistrellus pipistrellus/pygmaeus bats. The bats were collected across a gradient of metal pollution in England and Wales. The utility of small samples of fur as an indicator of metal exposure from the environment was demonstrated with strong relationships obtained between the concentrations of non-essential metals in fur with concentrations in stomach content, kidneys, liver and bones. Stronger relationships were observed for non-essential metals than for essential metals. Fur analyses might therefore be a useful non-invasive proxy for understanding recent, as well as long term and chronic, metal exposure of live animals. The use of fur may provide valuable information on the level of endogenous metal exposure and contamination of bat populations and communities.

  18. Non-invasive and non-destructive measurements of confluence in cultured adherent cell lines.

    PubMed

    Busschots, Steven; O'Toole, Sharon; O'Leary, John J; Stordal, Britta

    2015-01-01

    Many protocols used for measuring the growth of adherent monolayer cells in vitro are invasive, destructive and do not allow for the continued, undisturbed growth of cells within flasks. Protocols often use indirect methods for measuring proliferation. Microscopy techniques can analyse cell proliferation in a non-invasive or non-destructive manner but often use expensive equipment and software algorithms. In this method images of cells within flasks are captured by photographing under a standard inverted phase contract light microscope using a digital camera with a camera lens adaptor. Images are analysed for confluence using ImageJ freeware resulting in a measure of confluence known as an Area Fraction (AF) output. An example of the AF method in use on OVCAR8 and UPN251 cell lines is included. •Measurements of confluence from growing adherent cell lines in cell culture flasks is obtained in a non-invasive, non-destructive, label-free manner.•The technique is quick, affordable and eliminates sample manipulation.•The technique provides an objective, consistent measure of when cells reach confluence and is highly correlated to manual counting with a haemocytometer. The average correlation co-efficient from a Spearman correlation (n = 3) was 0.99 ± 0.008 for OVCAR8 (p = 0.01) and 0.99 ± 0.01 for UPN251 (p = 0.01) cell lines.

  19. A Non-Invasive Handheld Assistive Device to Accommodate Essential Tremor: A Pilot Study

    PubMed Central

    Pathak, Anupam; Redmond, John A.; Allen, Michael; Chou, Kelvin L.

    2014-01-01

    Background We explored whether a non-invasive, handheld device using Active Cancellation of Tremor (ACT) technology could stabilize tremor-induced motion of a spoon in individuals with essential tremor (ET). Methods Fifteen ET subjects (9M/6F) performed 3 tasks with the ACT device turned on and off. Tremor severity was rated with the Fahn-Tolosa-Marin Tremor Rating Scale (TRS). Subjective improvement was rated by subjects with the Clinical Global Impression Scale (CGI-S). Tremor amplitude was measured using device-embedded accelerometers in 11 subjects. Results TRS scores improved with ACT on (versus off) in all 3 tasks: holding (1.00±0.76 vs. 0.27±0.70, p=0.016), eating (1.47±1.06 vs. 0.13±0.64, p=0.001) and transferring (1.33±0.82 vs. 0.27±0.59, p=0.001). CGI-S improved with eating and transferring, but not the holding task. Accelerometer measurements demonstrated 71-76% reduction in tremor with ACT device on. Conclusions This non-invasive, handheld ACT device can reduce tremor amplitude and severity for eating and transferring tasks in individuals with ET. PMID:24375570

  20. The biological basis of non-invasive strategies for selection of human oocytes and embryos.

    PubMed

    Scott, Lynette

    2003-01-01

    There is a need for more accurate embryo selection in human assisted reproduction, if the goal of reducing the number of embryos used in embryo transfer is to be realized. Furthermore, any selection strategy should be non-invasive if the embryos are to be used in embryo transfer. Currently, the strategy is selection by one to three parameters in the cleaving- and blastocyst-stage embryo, sometimes with additional pronuclear selection. It is clear that no one system is ideal, as the vast majority of transferred embryos do not implant. As the health of the embryo is largely dictated by the originating gametes, the very early events in oocyte development should be considered. This review will point to the early biological events in the unfertilized and fertilized oocyte that can be scored non-invasively and which can have a profound effect on the later developmental stages. Using a sequential scoring system, with emphasis on the oocyte, a system for selecting the most viable single embryo for transfer may hopefully be achieved.

  1. Non-invasive, serum DNA pregnancy testing leading to incidental discovery of cancer: a good thing?

    PubMed

    Prasad, Vinay

    2015-11-01

    Cell-free DNA for perinatal screening is a growing industry. Non-invasive prenatal testing (NIPT) is based on the premise that foetal DNA is able to cross the placental barrier and enter the mother's circulation, where it can be examined for chromosomal abnormalities, such as trisomy 13, 18 or 21. Such tests are expected to be widely used by pregnant women, with the annual market expected to surpass $1 billion. Recently, a number of case reports have emerged in the haematology-oncology literature. The routine use of NIPT has led to the discovery of maternal neoplasms. Most writers have concluded that this is yet another benefit of the test; however, a closer examination of the cases reveals that this incidental detection may not improve patient outcomes. In some cases, early detection provides lead time bias, but does not change the ultimate clinical outcome, and in other cases, detection constitutes earlier knowledge of a cancer whose natural history cannot be altered. Here, we explore in detail cases where cancer was incidentally discovered among women undergoing routine non-invasive pregnancy testing, and investigate whether or not these women were benefitted by the discovery.

  2. Non-invasive and non-destructive measurements of confluence in cultured adherent cell lines

    PubMed Central

    Busschots, Steven; O’Toole, Sharon; O’Leary, John J.; Stordal, Britta

    2014-01-01

    Many protocols used for measuring the growth of adherent monolayer cells in vitro are invasive, destructive and do not allow for the continued, undisturbed growth of cells within flasks. Protocols often use indirect methods for measuring proliferation. Microscopy techniques can analyse cell proliferation in a non-invasive or non-destructive manner but often use expensive equipment and software algorithms. In this method images of cells within flasks are captured by photographing under a standard inverted phase contract light microscope using a digital camera with a camera lens adaptor. Images are analysed for confluence using ImageJ freeware resulting in a measure of confluence known as an Area Fraction (AF) output. An example of the AF method in use on OVCAR8 and UPN251 cell lines is included. • Measurements of confluence from growing adherent cell lines in cell culture flasks is obtained in a non-invasive, non-destructive, label-free manner. • The technique is quick, affordable and eliminates sample manipulation. • The technique provides an objective, consistent measure of when cells reach confluence and is highly correlated to manual counting with a haemocytometer. The average correlation co-efficient from a Spearman correlation (n = 3) was 0.99 ± 0.008 for OVCAR8 (p = 0.01) and 0.99 ± 0.01 for UPN251 (p = 0.01) cell lines. PMID:26150966

  3. Development of a portable non-invasive swallowing and respiration assessment device.

    PubMed

    Shieh, Wann-Yun; Wang, Chin-Man; Chang, Chia-Shuo

    2015-01-01

    Dysphagia is a condition that happens when a person cannot smoothly swallow food from the mouth to the stomach. It causes malnourishment in patients, or can even cause death due to aspiration pneumonia. Recently, more and more researchers have focused their attention on the importance of swallowing and respiration coordination, and the use of non-invasive assessment systems has become a hot research trend. In this study, we aimed to integrate the timing and pattern monitoring of respiration and swallowing by using a portable and non-invasive approach which can be applied at the bedside in hospitals or institutions, or in a home environment. In this approach, we use a force sensing resistor (FSR) to detect the motions of the thyroid cartilage in the pharyngeal phase. We also use the surface electromyography (sEMG) to detect the contraction of the submental muscle in the oral phase, and a nasal cannula to detect nasal airflow for respiration monitoring during the swallowing process. All signals are received and processed for swallowing event recognition. A total of 19 volunteers participated in the testing and over 57 measurements were made. The results show that the proposed approach can effectively distinguish the swallowing function in people of different ages and genders.

  4. Deconstructing autofluorescence: non-invasive detection and monitoring of biochemistry in cells and tissues (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Goldys, Ewa M.; Gosnell, Martin E.; Anwer, Ayad G.; Cassano, Juan C.; Sue, Carolyn M.; Mahbub, Saabah B.; Pernichery, Sandeep M.; Inglis, David W.; Adhikary, Partho P.; Jazayeri, Jalal A.; Cahill, Michael A.; Saad, Sonia; Pollock, Carol; Sutton-Mcdowall, Melanie L.; Thompson, Jeremy G.

    2016-03-01

    Automated and unbiased methods of non-invasive cell monitoring able to deal with complex biological heterogeneity are fundamentally important for biology and medicine. Label-free cell imaging provides information about endogenous fluorescent metabolites, enzymes and cofactors in cells. However extracting high content information from imaging of native fluorescence has been hitherto impossible. Here, we quantitatively characterise cell populations in different tissue types, live or fixed, by using novel image processing and a simple multispectral upgrade of a wide-field fluorescence microscope. Multispectral intrinsic fluorescence imaging was applied to patient olfactory neurosphere-derived cells, cell model of a human metabolic disease MELAS (mitochondrial myopathy, encephalomyopathy, lactic acidosis, stroke-like syndrome). By using an endogenous source of contrast, subtle metabolic variations have been detected between living cells in their full morphological context which made it possible to distinguish healthy from diseased cells before and after therapy. Cellular maps of native fluorophores, flavins, bound and free NADH and retinoids unveiled subtle metabolic signatures and helped uncover significant cell subpopulations, in particular a subpopulation with compromised mitochondrial function. The versatility of our method is further illustrated by detecting genetic mutations in cancer, non-invasive monitoring of CD90 expression, label-free tracking of stem cell differentiation, identifying stem cell subpopulations with varying functional characteristics, tissue diagnostics in diabetes, and assessing the condition of preimplantation embryos. Our optimal discrimination approach enables statistical hypothesis testing and intuitive visualisations where previously undetectable differences become clearly apparent.

  5. The quest for non-invasive delivery of bioactive macromolecules: A focus on heparins

    PubMed Central

    Motlekar, Nusrat A.; Youan, Bi-Botti C.

    2006-01-01

    The development of a non-invasive drug delivery system for unfractionated heparin (UFH) and low molecular weight heparins (LMWHs) has been the elusive goal of several research groups since the initial discovery of this glycosaminogylcan by McLean in 1916. After a brief update on current parenteral formulations of UFH and LMWHs, this review revisits past and current strategies intended to identify alternative routes of administration (e.g. oral, sublingual, rectal, nasal, pulmonary and transdermal). The following strategies have been used to improve the bioavailability of this bioactive macromolecule by various routes: (i) enhancement in cell-membrane permeabilization, (ii) modification of the tight-junctions, (iii) increase in lipophilicity and (iv) protection against acidic pH of the stomach. Regardless of the route of administration, a simplified unifying principle for successful non-invasive macromolecular drug delivery may be: “to reversibly overcome the biological, biophysical and biochemical barriers and to safely and efficiently improve the in vivo spatial and temporal control of the drug in order to achieve a clinically acceptable therapeutic advantage”. Future macromolecular drug delivery research should embrace a more systemic approach taking into account recent advances in genomics/proteomics and nanotechnology. PMID:16777255

  6. Non-alcoholic fatty liver disease: non-invasive investigation and risk stratification.

    PubMed

    Dyson, J K; McPherson, S; Anstee, Q M

    2013-12-01

    Non-alcoholic fatty liver disease (NAFLD) encompasses a histological spectrum of liver disease, from simple steatosis through to cirrhosis. As the worldwide rates of obesity have increased, NAFLD has become the commonest cause of liver disease in many developed countries, affecting up to a third of the population. The majority of patients have simple steatosis that carries a relatively benign prognosis. However, a significant minority have non-alcoholic steatohepatitis, and have increased liver related and cardiovascular mortality. Identifying those at risk of progressive disease is crucial. Liver biopsy remains the gold standard investigation for assessing stage of disease but its invasive nature makes it impractical for widespread use as a prognostic tool. Non-invasive tools for diagnosis and disease staging are required, reserving liver biopsy for those patients where it offers clinically relevant additional information. This review discusses the non-invasive modalities available for assessing steatosis, steatohepatitis and fibrosis. We propose a pragmatic approach for the assessment of patients with NAFLD to identify those at high risk of progressive disease who require referral to specialist services. PMID:23940130

  7. Quantitative non-invasive cell characterisation and discrimination based on multispectral autofluorescence features

    PubMed Central

    Gosnell, Martin E.; Anwer, Ayad G.; Mahbub, Saabah B.; Menon Perinchery, Sandeep; Inglis, David W.; Adhikary, Partho P.; Jazayeri, Jalal A.; Cahill, Michael A.; Saad, Sonia; Pollock, Carol A.; Sutton-McDowall, Melanie L.; Thompson, Jeremy G.; Goldys, Ewa M.

    2016-01-01

    Automated and unbiased methods of non-invasive cell monitoring able to deal with complex biological heterogeneity are fundamentally important for biology and medicine. Label-free cell imaging provides information about endogenous autofluorescent metabolites, enzymes and cofactors in cells. However extracting high content information from autofluorescence imaging has been hitherto impossible. Here, we quantitatively characterise cell populations in different tissue types, live or fixed, by using novel image processing and a simple multispectral upgrade of a wide-field fluorescence microscope. Our optimal discrimination approach enables statistical hypothesis testing and intuitive visualisations where previously undetectable differences become clearly apparent. Label-free classifications are validated by the analysis of Classification Determinant (CD) antigen expression. The versatility of our method is illustrated by detecting genetic mutations in cancer, non-invasive monitoring of CD90 expression, label-free tracking of stem cell differentiation, identifying stem cell subpopulations with varying functional characteristics, tissue diagnostics in diabetes, and assessing the condition of preimplantation embryos. PMID:27029742

  8. Breath Analysis as a Potential and Non-Invasive Frontier in Disease Diagnosis: An Overview

    PubMed Central

    Pereira, Jorge; Porto-Figueira, Priscilla; Cavaco, Carina; Taunk, Khushman; Rapole, Srikanth; Dhakne, Rahul; Nagarajaram, Hampapathalu; Câmara, José S.

    2015-01-01

    Currently, a small number of diseases, particularly cardiovascular (CVDs), oncologic (ODs), neurodegenerative (NDDs), chronic respiratory diseases, as well as diabetes, form a severe burden to most of the countries worldwide. Hence, there is an urgent need for development of efficient diagnostic tools, particularly those enabling reliable detection of diseases, at their early stages, preferably using non-invasive approaches. Breath analysis is a non-invasive approach relying only on the characterisation of volatile composition of the exhaled breath (EB) that in turn reflects the volatile composition of the bloodstream and airways and therefore the status and condition of the whole organism metabolism. Advanced sampling procedures (solid-phase and needle traps microextraction) coupled with modern analytical technologies (proton transfer reaction mass spectrometry, selected ion flow tube mass spectrometry, ion mobility spectrometry, e-noses, etc.) allow the characterisation of EB composition to an unprecedented level. However, a key challenge in EB analysis is the proper statistical analysis and interpretation of the large and heterogeneous datasets obtained from EB research. There is no standard statistical framework/protocol yet available in literature that can be used for EB data analysis towards discovery of biomarkers for use in a typical clinical setup. Nevertheless, EB analysis has immense potential towards development of biomarkers for the early disease diagnosis of diseases. PMID:25584743

  9. Electro-resistive bands for non-invasive cardiac and respiration monitoring, a feasibility study.

    PubMed

    Gargiulo, Gaetano D; O'Loughlin, Aiden; Breen, Paul P

    2015-02-01

    Continuous unobtrusive monitoring of tidal volume, particularly for critical care patients (i.e. neonates and patients in intensive care) during sleep studies and during daily activities, is still an unresolved monitoring need. Also a successful monitoring solution is yet to be proposed for continuous non-invasive cardiac stroke volume monitoring that is a novel clinical need.In this paper we present the feasibility study for a wearable, non-invasive, non-contact and unobtrusive sensor (embedded in a standard T-shirt) based on four electro-resistive bands that simultaneously monitors tidal volume and cardiac stroke volume changes. This low power sensor system (requires only 100 mW and accepts a wide power supply range up to ±18 V); thus the sensor can be easily embedded in existing wearable solutions (i.e. Holter monitors). Moreover, being contactless, it can be worn over bandages or electrodes, and as it does not rely over the integrity of the garment to work, it allows practitioners to perform procedures during monitoring. For this preliminary evaluation, one subject has worn the sensor over the period of 24 h (removing it only to shower); the accuracy of the tidal volume tested against a portable spirometer reported a precision of ±10% also during physical activity; accuracy tests for cardiac output (as it may require invasive procedure) have not been carried out in this preliminary trial.

  10. Non-invasive health status detection system using Gabor filters based on facial block texture features.

    PubMed

    Shu, Ting; Zhang, Bob

    2015-04-01

    Blood tests allow doctors to check for certain diseases and conditions. However, using a syringe to extract the blood can be deemed invasive, slightly painful, and its analysis time consuming. In this paper, we propose a new non-invasive system to detect the health status (Healthy or Diseased) of an individual based on facial block texture features extracted using the Gabor filter. Our system first uses a non-invasive capture device to collect facial images. Next, four facial blocks are located on these images to represent them. Afterwards, each facial block is convolved with a Gabor filter bank to calculate its texture value. Classification is finally performed using K-Nearest Neighbor and Support Vector Machines via a Library for Support Vector Machines (with four kernel functions). The system was tested on a dataset consisting of 100 Healthy and 100 Diseased (with 13 forms of illnesses) samples. Experimental results show that the proposed system can detect the health status with an accuracy of 93 %, a sensitivity of 94 %, a specificity of 92 %, using a combination of the Gabor filters and facial blocks. PMID:25722202

  11. Non-Invasive Assessment of Viability in Human Embryos Fertilized in Vitro

    PubMed Central

    Montskó, Gergely; Zrínyi, Zita; Farkas, Nelli; Várnagy, Ákos; Bódis, József

    2016-01-01

    Human reproduction is a relatively inefficient process and therefore the number of infertile couples is high. Assisted reproductive technologies (ART) have facilitated the birth of over five million children worldwide. ART, however, superimposes its own relative inefficiency on the preexisting inefficiency of normal reproduction. The efficiency (expressed as pregnancy rate) is generally not more than 30%. Modern reproductive medicine is gradually moving from multiple embryo transfer to the transfer of a single embryo, mainly because of obvious and unwanted side effects of multiple embryo transfer (e.g. „epidemic” multiple pregnancies). This concept, however, requires a fast, professional selection of the most viable embryo during the first few days of ART. Thus the aim of a modern ART is the safe transfer of a healthy, viable, single embryo. Accurate and rapid methods of quantifying embryo viability are needed to reach this goal. Methodological advances have the potential to make an important contribution, and there has been a drive to develop alternative non-invasive methods to better meet clinical needs. Metabolic and genetic profiling of spent embryo culture (SEC) media should offer an exceptional opportunity for the assessment of embryo viability. The current review focuses on the latest non-invasive diagnostic approaches for pre-implantation viability assessment of in vitro fertilized embryos. PMID:27683524

  12. Injury and repair in perinatal brain injury: Insights from non-invasive MR perfusion imaging.

    PubMed

    Wintermark, Pia

    2015-03-01

    Injury to the developing brain remains an important complication in critically ill newborns, placing them at risk for future neurodevelopment impairments. Abnormal brain perfusion is often a key mechanism underlying neonatal brain injury. A better understanding of how alternations in brain perfusion can affect normal brain development will permit the development of therapeutic strategies that prevent and/or minimize brain injury and improve the neurodevelopmental outcome of these high-risk newborns. Recently, non-invasive MR perfusion imaging of the brain has been successfully applied to the neonatal brain, which is known to be smaller and have lower brain perfusion compared to older children and adults. This article will present an overview of the potential role of non-invasive perfusion imaging by MRI to study maturation, injury, and repair in perinatal brain injury and demonstrate why this perfusion sequence is an important addition to current neonatal imaging protocols, which already include different sequences to assess the anatomy and metabolism of the neonatal brain.

  13. Differences in cap formation between invasive Entamoeba histolytica and non-invasive Entamoeba dispar.

    PubMed

    Chávez-Munguía, Bibiana; Talamás-Rohana, Patricia; Castañón, Guadalupe; Salazar-Villatoro, Lizbeth; Hernández-Ramírez, Verónica; Martínez-Palomo, Adolfo

    2012-07-01

    The rapid redistribution of surface antigen-antibody complexes in trophozoites of the human protozoan parasite Entamoeba histolytica, in a process known as capping, has been considered as a means of the parasite to evade the host immune response. So far, capping has been documented in the invasive E. histolytica, whereas the mobility of surface components in the non-invasive Entamoeba dispar is not known. E. dispar does not induce liver lesions in rodent experimental models, in contrast to the liver abscesses produced by E. histolytica in the same animal model. We have therefore analyzed the mobility of surface receptors to the lectin concanavalin A and of Rab11, a membrane-associated protein, in both species of Entamoebae by confocal fluorescence microscopy and transmission and scanning electron microscopy. The great majority of E. histolytica trophozoites became morphologically polarized through the formation of well-defined caps at the posterior pole of the parasite. Actin colocalized with the lectin caps. Antibodies against the membrane protein Rab 11 also produced capping. In striking contrast, in E. dispar, the mobility of concanavalin A surface receptors was restricted to the formation of irregular surface patches that did no progress to constitute well-defined caps. Also, anti-Rab 11 antibodies did not result in capping in E. dispar. Whether the failure of E. dispar to efficiently mobilize surface molecules in response to lectin or antibodies as shown in the present results is related to its non-invasive character represents an interesting hypothesis requiring further analysis.

  14. Limitations of Stroke Volume Estimation by Non-Invasive Blood Pressure Monitoring in Hypergravity

    PubMed Central

    2015-01-01

    Background Altitude and gravity changes during aeromedical evacuations induce exacerbated cardiovascular responses in unstable patients. Non-invasive cardiac output monitoring is difficult to perform in this environment with limited access to the patient. We evaluated the feasibility and accuracy of stroke volume estimation by finger photoplethysmography (SVp) in hypergravity. Methods Finger arterial blood pressure (ABP) waveforms were recorded continuously in ten healthy subjects before, during and after exposure to +Gz accelerations in a human centrifuge. The protocol consisted of a 2-min and 8-min exposure up to +4 Gz. SVp was computed from ABP using Liljestrand, systolic area, and Windkessel algorithms, and compared with reference values measured by echocardiography (SVe) before and after the centrifuge runs. Results The ABP signal could be used in 83.3% of cases. After calibration with echocardiography, SVp changes did not differ from SVe and values were linearly correlated (p<0.001). The three algorithms gave comparable SVp. Reproducibility between SVp and SVe was the best with the systolic area algorithm (limits of agreement −20.5 and +38.3 ml). Conclusions Non-invasive ABP photoplethysmographic monitoring is an interesting technique to estimate relative stroke volume changes in moderate and sustained hypergravity. This method may aid physicians for aeronautic patient monitoring. PMID:25798613

  15. Integrated microsystem for non-invasive electrophysiological measurements on Xenopus oocytes.

    PubMed

    Dahan, E; Bize, V; Lehnert, T; Horisberger, J-D; Gijs, M A M

    2007-06-15

    We propose a new non-invasive integrated microsystem for electrophysiological measurements on Xenopus laevis oocytes. Xenopus oocyte is a well-known expression system for various kinds of ion channels, that are potential tools in drug screening. In the traditional "Two Electrode Voltage Clamp" (TEVC) method, delicate micromanipulation is required to impale an oocyte with two microelectrodes. In our system, a non-invasive electrical access to the cytoplasm is provided by permeabilizing the cell membrane with an ionophore (e.g. nystatin). Unlike the classical patch-clamp or "macropatch" techniques, this method does not require removal of the vitelline membrane. Cell handling is significantly simplified, resulting in more robust recordings with increased throughput. Moreover, because only part of the oocyte surface is exposed to reagents, the required volume of reagent solutions could be reduced by an order of magnitude compared to the TEVC method. The fabrication process for this disposable microchip, based on poly-dimethylsiloxane (PDMS) molding and glass/PDMS bonding, is cost-efficient and simple. We tested this new microdevice by recording currents in oocytes expressing the human Epithelial Sodium Channel (hENaC) for membrane potentials between -100 and +50 mV. We recorded benzamil-sensitive currents with a large signal-to-noise ratio and we also obtained a benzamil concentration-inhibition curve displaying an inhibition constant IC(50) of about 50 nM, comparable to previously published values obtained with the TEVC technique.

  16. Non-Invasive Assessment of Viability in Human Embryos Fertilized in Vitro.

    PubMed

    Kovács, Gábor L; Montskó, Gergely; Zrínyi, Zita; Farkas, Nelli; Várnagy, Ákos; Bódis, József

    2016-04-01

    Human reproduction is a relatively inefficient process and therefore the number of infertile couples is high. Assisted reproductive technologies (ART) have facilitated the birth of over five million children worldwide. ART, however, superimposes its own relative inefficiency on the preexisting inefficiency of normal reproduction. The efficiency (expressed as pregnancy rate) is generally not more than 30%. Modern reproductive medicine is gradually moving from multiple embryo transfer to the transfer of a single embryo, mainly because of obvious and unwanted side effects of multiple embryo transfer (e.g. "epidemic" multiple pregnancies). This concept, however, requires a fast, professional selection of the most viable embryo during the first few days of ART. Thus the aim of a modern ART is the safe transfer of a healthy, viable, single embryo. Accurate and rapid methods of quantifying embryo viability are needed to reach this goal. Methodological advances have the potential to make an important contribution, and there has been a drive to develop alternative non-invasive methods to better meet clinical needs. Metabolic and genetic profiling of spent embryo culture (SEC) media should offer an exceptional opportunity for the assessment of embryo viability. The current review focuses on the latest non-invasive diagnostic approaches for pre-implantation viability assessment of in vitro fertilized embryos. PMID:27683524

  17. Monitoring high-risk patients: minimally invasive and non-invasive possibilities.

    PubMed

    Renner, Jochen; Grünewald, Matthias; Bein, Berthold

    2016-06-01

    Over the past decades, there has been considerable progress in the field of less invasive haemodynamic monitoring technologies. Substantial evidence has accumulated, which supports the continuous measurement and optimization of flow-based variables such as stroke volume, that is, cardiac output, in order to prevent occult hypoperfusion and consequently to improve patients' outcome in the perioperative setting. However, there is a striking gap between the developments in haemodynamic monitoring and the increasing evidence to implement defined treatment protocols based on the measured variables, and daily clinical routine. Recent trials have shown that perioperative morbidity and mortality is higher than anticipated. This emphasizes the need for the anaesthesia community to address this issue and promotes the implementation of proven concepts into clinical practice in order to improve patients' outcome, especially in high-risk patients. The advances in minimally invasive and non-invasive monitoring techniques can be seen as a driving force in this respect, as the degree of invasiveness of any monitoring tool determines the frequency of its application, especially in the operating room (OR). From this point of view, we are very confident that some of these minimally invasive and non-invasive haemodynamic monitoring technologies will become an inherent part of our monitoring armamentarium in the OR and in the intensive care unit (ICU). PMID:27396807

  18. Non-invasive Investigations of Paintings by Portable Instrumentation: The MOLAB Experience.

    PubMed

    Brunetti, B; Miliani, C; Rosi, F; Doherty, B; Monico, L; Romani, A; Sgamellotti, A

    2016-02-01

    The in situ non invasive methods have experienced a significant development in the last decade because they meet specific needs of analytical chemistry in the field of cultural heritage where  artworks are rarely moved from their locations, sampling is rarely permitted, and analytes are a wide range of inorganic, organic and organometallic substances in complex and precious matrices. MOLAB, a unique collection of integrated mobile instruments, has greatly contributed to demonstrate that it is now possible to obtain satisfactory results in the study of a variety of heritage objects without sampling or moving them to a laboratory. The current chapter describes an account of these results with particular attention to ancient, modern, and contemporary paintings. Several non-invasive methods by portable equipment, including XRF, mid- and near-FTIR, UV-Vis and Raman spectroscopy, as well as XRD, are discussed in detail along with their impact on our understanding of painting materials and execution techniques. Examples of successful applications are given, both for point analyses and hyperspectral imaging approaches. Lines for future perspectives are finally drawn. PMID:27572993

  19. Non-invasive and in vivo assessment of osteoarthritic articular cartilage: a review on MRI investigations.

    PubMed

    Hani, Ahmad Fadzil Mohd; Kumar, Dileep; Malik, Aamir Saeed; Ahmad, Raja Mohd Kamil Raja; Razak, Ruslan; Kiflie, Azman

    2015-01-01

    Early detection of knee osteoarthritis (OA) is of great interest to orthopaedic surgeons, rheumatologists, radiologists, and researchers because it would allow physicians to provide patients with treatments and advice to slow the onset or progression of the disease. Early detection can be achieved by identifying early changes in selected features of degenerative articular cartilage (AC) using non-invasive imaging modalities. Magnetic resonance imaging (MRI) is becoming the standard for assessment of OA. The aim of this paper was to review the influence of MRI on the selection, detection, and measurement of AC features associated with early OA. Our review of the literature indicates that the changes associated with early OA are in cartilage thickness, cartilage volume, cartilage water content, and proteoglycan content that can be accurately, consistently, and non-invasively measured using MRI. Choosing an MR pulse sequence that provides the capability to assess cartilage physiology and morphology in a single acquisition and advanced multi-nuclei MRI is desirable. The results of the review indicate that using an ultra-high magnetic strength, MR imager does not affect early OA detection. In conclusion, MRI is currently the most suitable modality for early detection of knee OA, and future research should focus on the quantitative evaluation of early OA features using advances in MR hardware, software, and data processing with sophisticated image/pattern recognition techniques.

  20. Non-Invasive Assessment of Viability in Human Embryos Fertilized in Vitro

    PubMed Central

    Montskó, Gergely; Zrínyi, Zita; Farkas, Nelli; Várnagy, Ákos; Bódis, József

    2016-01-01

    Human reproduction is a relatively inefficient process and therefore the number of infertile couples is high. Assisted reproductive technologies (ART) have facilitated the birth of over five million children worldwide. ART, however, superimposes its own relative inefficiency on the preexisting inefficiency of normal reproduction. The efficiency (expressed as pregnancy rate) is generally not more than 30%. Modern reproductive medicine is gradually moving from multiple embryo transfer to the transfer of a single embryo, mainly because of obvious and unwanted side effects of multiple embryo transfer (e.g. „epidemic” multiple pregnancies). This concept, however, requires a fast, professional selection of the most viable embryo during the first few days of ART. Thus the aim of a modern ART is the safe transfer of a healthy, viable, single embryo. Accurate and rapid methods of quantifying embryo viability are needed to reach this goal. Methodological advances have the potential to make an important contribution, and there has been a drive to develop alternative non-invasive methods to better meet clinical needs. Metabolic and genetic profiling of spent embryo culture (SEC) media should offer an exceptional opportunity for the assessment of embryo viability. The current review focuses on the latest non-invasive diagnostic approaches for pre-implantation viability assessment of in vitro fertilized embryos.

  1. Using Diagnostic Radioentomology for Non-Invasive Observations of Colonies of the Bumblebee, Bombus terrestris

    PubMed Central

    Greco, Mark K.; Sadd, Ben M.

    2012-01-01

    Bumblebees have been the focus of a broad range of scientific research due to their behavior, social life, and a number of other intriguing traits. Current methods for examining their nest structure, such as natal cells and contents of storage cells, are destructive in nature because the cells need to be opened for physical inspections. This research describes how the internal structures of the artificial nests of the bumblebee Bombus terrestris L. (Hymentoptera: Apidae) were non-invasively viewed and assessed by using diagnostic radioentomology. For the first time, B. terrestris nest structures, and their contents such as larvae, pupae and eggs, were non-invaseively viewed and assessed. This technique will enable future experiments to take morphological measurements of egg, larval, and pupal development over time. Moreover, combining these measurements with measures of food-storage will provide a good assessment of colony health. The method will also allow tracking of individually marked adults, to monitor their behaviour and help gain a better understanding of the processes involved in the global declines of B. terrestris, which will in turn promote better management of these valuable pollinators. PMID:23421622

  2. [Non invasive intracranial hyperthermia with Electric Capacitive Transference -ECT- Intratumoral and cerebral thermometry results].

    PubMed

    Ley-Valle, A

    2003-02-01

    The aim of this work is to present the results of thermic increase obtained at the brain and intratumoral levels through a non invasive technique -Electric Capacitive Transference- (ECT), developed in 1985 by Indiba. A review of the literature does not provide any reference of cerebral and intratumoral thermometry in real time with a non invasive technique of intracranial hyperthermia. In the 8 studied patients, the increases of temperature in the brain, ranged between 0.7 and 1.5 degrees C in relation to the depth of the thermometric probe and the incidence angle of the external electrode. Between tumoral and perilesional brain tissues, thermic increase was 0.3 to 0.7 degrees C greater at tumoral level. The observation that in no case the surrounding brain tissue registered a temperature over 39.2 degrees C supports the harmlessness of the technique regarding the potential damage to healthy brain tissue and seems to confirm previous data obtained in anatomopathological studies in animal experimentation performed in 1990, which showed an absence of lesions in tissues and organs. The greater and somewhat more prolonged thermic increase observed at tumoral level has been called the "greenhouse effect".

  3. The challenge to detect heart transplant rejection and transplant vasculopathy non-invasively - a pilot study

    PubMed Central

    Usta, Engin; Burgstahler, Christof; Aebert, Hermann; Schroeder, Stephen; Helber, Uwe; Kopp, Andreas F; Ziemer, Gerhard

    2009-01-01

    Background Cardiac allograft rejection and vasculopathy are the main factors limiting long-term survival after heart transplantation. In this pilot study we investigated whether non-invasive methods are beneficial to detect cardiac allograft rejection (Grade 0-3 R) and cardiac allograft vasculopathy. Thus we compared multi-slice computed tomography and magnetic resonance imaging with invasive methods like coronary angiography and left endomyocardial biopsy. Methods 10 asymptomatic long-term survivors after heart transplantation (8 male, 2 female, mean age 52.1 ± 12 years, 73 ± 11 months after transplantation) were included. In a blinded fashion, coronary angiography and multi-slice computed tomography and ventricular endomyocardial biopsy and magnetic resonance imaging were compared against each other. Results Cardiac allograft vasculopathy and atherosclerosis were correctly detected by multi-slice computed tomography and coronary angiography with positive correlation (r = 1). Late contrast enchancement found by magnetic resonance imaging correlated positively (r = 0.92, r2 = 0.85, p < 0.05) with the histological diagnosis of transplant rejection revealed by myocardial biopsy. None of the examined endomyocardial specimen revealed cardiac allograft rejection greater than Grade 1 R. Conclusion A combined non-invasive approach using multi-slice computed tomography and magnetic resonance imaging may help to assess cardiac allograft vasculopathy and cardiac allograft rejection after heart transplantation before applying more invasive methods. PMID:19682394

  4. Non-invasive investigations successfully select patients for temporal lobe surgery

    PubMed Central

    Kilpatrick, C.; Cook, M.; Kaye, A.; Murphy, M.; Matkovic, Z.

    1997-01-01

    OBJECTIVES—There is controversy regarding the need for invasive monitoring in the preoperative assessment of patients with temporal lobe epilepsy. The use of a series of non-invasive investigations in identifying the seizure focus is reported in 75 consecutive adults referred for epilepsy surgery.
METHODS—All had video-EEG monitoring using scalp electrodes, high resolution MRI, and neuropsychology assessment. Other investigations included volumetric MRI, PET, and ictal and interictal SPECT. The seizure focus was localised and surgery offered if MRI disclosed unilateral hippocampal atrophy or a foreign tissue lesion and other investigations were either concordant or not discordant.
RESULTS—In 68 patients the seizure focus was localised and three patients were inoperable. Sixty five patients have been offered surgery and 50 have undergone temporal lobe surgery and have a follow up of at least 12 months (mean 24 months). All had pathology: hippocampal sclerosis 34, dysembryoblastic neuroepithelial tumour six, cavernoma four, dysplasia two, low grade glioma two, ganglioglioma two. Thirty nine patients (78%) are seizure free postoperatively, 29/34 with hippocampal sclerosis and 10/16 with a foreign tissue lesion. Of the 11 patients with postoperative recurrent seizures, eight have a >90% reduction in seizure frequency and three have <90% reduction in seizure frequency but a worthwhile improvement.
CONCLUSIONS—Non-invasive investigations successfully select most patients for temporal lobe surgery.

 PMID:9328249

  5. Non-invasive method and apparatus for monitoring intracranial pressure and pressure volume index in humans

    NASA Technical Reports Server (NTRS)

    Yost, William T. (Inventor); Cantrell, Jr., John H. (Inventor)

    1997-01-01

    Non-invasive measuring devices responsive to changes in a patient's intracranial pressure (ICP) can be accurately calibrated for monitoring purposes by providing known changes in ICP by non-invasive methods, such as placing the patient on a tilting bed and calculating a change in ICP from the tilt angle and the length of the patient's cerebrospinal column, or by placing a pressurized skull cap on the patient and measuring the inflation pressure. Absolute values for the patient's pressure-volume index (PVI) and the steady state ICP can then be determined by inducing two known changes in the volume of cerebrospinal fluid while recording the corresponding changes in ICP by means of the calibrated measuring device. The two pairs of data for pressure change and volume change are entered into an equation developed from an equation describing the relationship between ICP and cerebrospinal fluid volume. PVI and steady state ICP are then determined by solving the equation. Methods for inducing known changes in cerebrospinal fluid volume are described.

  6. Portable, Non-Invasive Fall Risk Assessment in End Stage Renal Disease Patients on Hemodialysis.

    PubMed

    Lockhart, Thurmon E; Barth, Adam T; Zhang, Xiaoyue; Songra, Rahul; Abdel-Rahman, Emaad; Lach, John

    2010-01-01

    Patients with end stage renal diseases (ESRD) on hemodialysis (HD) have high morbidity and mortality due to multiple causes, one of which is dramatically higher fall rates than the general population. The mobility mechanisms that contribute to falls in this population must be understood if adequate interventions for fall prevention are to be achieved. This study utilizes emerging non-invasive, portable gait, posture, strength, and stability assessment technologies to extract various mobility parameters that research has shown to be predictive of fall risk in the general population. As part of an ongoing human subjects study, mobility measures such as postural and locomotion profiles were obtained from five (5) ESRD patients undergoing HD treatments. To assess the effects of post-HD-fatigue on fall risk, both the pre- and post-HD measurements were obtained. Additionally, the effects of inter-HD periods (two days vs. three days) were investigated using the non-invasive, wireless, body-worn motion capture technology and novel signal processing algorithms. The results indicated that HD treatment influenced strength and mobility (i.e., weaker and slower after the dialysis, increasing the susceptibility to falls while returning home) and inter-dialysis period influenced pre-HD profiles (increasing the susceptibility to falls before they come in for a HD treatment). Methodology for early detection of increased fall risk - before a fall event occurs - using the portable mobility assessment technology for out-patient monitoring is further explored, including targeting interventions to identified individuals for fall prevention.

  7. Non-invasive ventilation in prone position for refractory hypoxemia after bilateral lung transplantation.

    PubMed

    Feltracco, Paolo; Serra, Eugenio; Barbieri, Stefania; Persona, Paolo; Rea, Federico; Loy, Monica; Ori, Carlo

    2009-01-01

    Temporary graft dysfunction with gas exchange abnormalities is a common finding during the postoperative course of a lung transplant and is often determined by the post-reimplantation syndrome. Supportive measures including oxygen by mask, inotropes, diuretics, and pulmonary vasodilators are usually effective in non-severe post-reimplantation syndromes. However, in less-responsive clinical pictures, tracheal intubation with positive pressure ventilation, or non-invasive positive pressure ventilation (NIV), is necessary. We report on the clinical course of two patients suffering from refractory hypoxemia due to post-reimplantation syndrome treated with NIV in the prone and Trendelenburg positions. NIV was well tolerated and led to resolution of atelectactic areas and dishomogeneous lung infiltrates. Repeated turning from supine to prone under non invasive ventilation determined a stable improvement of gas exchange and prevented a more invasive approach. Even though NIV in the prone position has not yet entered into clinical practice, it could be an interesting option to achieve a better match between ventilation and perfusion. This technique, which we successfully applied in lung transplantation, can be easily extended to other lung diseases with non-recruitable dorso-basal areas.

  8. Non-invasive, serum DNA pregnancy testing leading to incidental discovery of cancer: a good thing?

    PubMed

    Prasad, Vinay

    2015-11-01

    Cell-free DNA for perinatal screening is a growing industry. Non-invasive prenatal testing (NIPT) is based on the premise that foetal DNA is able to cross the placental barrier and enter the mother's circulation, where it can be examined for chromosomal abnormalities, such as trisomy 13, 18 or 21. Such tests are expected to be widely used by pregnant women, with the annual market expected to surpass $1 billion. Recently, a number of case reports have emerged in the haematology-oncology literature. The routine use of NIPT has led to the discovery of maternal neoplasms. Most writers have concluded that this is yet another benefit of the test; however, a closer examination of the cases reveals that this incidental detection may not improve patient outcomes. In some cases, early detection provides lead time bias, but does not change the ultimate clinical outcome, and in other cases, detection constitutes earlier knowledge of a cancer whose natural history cannot be altered. Here, we explore in detail cases where cancer was incidentally discovered among women undergoing routine non-invasive pregnancy testing, and investigate whether or not these women were benefitted by the discovery. PMID:26278647

  9. Electromyography data for non-invasive naturally-controlled robotic hand prostheses

    PubMed Central

    Atzori, Manfredo; Gijsberts, Arjan; Castellini, Claudio; Caputo, Barbara; Hager, Anne-Gabrielle Mittaz; Elsig, Simone; Giatsidis, Giorgio; Bassetto, Franco; Müller, Henning

    2014-01-01

    Recent advances in rehabilitation robotics suggest that it may be possible for hand-amputated subjects to recover at least a significant part of the lost hand functionality. The control of robotic prosthetic hands using non-invasive techniques is still a challenge in real life: myoelectric prostheses give limited control capabilities, the control is often unnatural and must be learned through long training times. Meanwhile, scientific literature results are promising but they are still far from fulfilling real-life needs. This work aims to close this gap by allowing worldwide research groups to develop and test movement recognition and force control algorithms on a benchmark scientific database. The database is targeted at studying the relationship between surface electromyography, hand kinematics and hand forces, with the final goal of developing non-invasive, naturally controlled, robotic hand prostheses. The validation section verifies that the data are similar to data acquired in real-life conditions, and that recognition of different hand tasks by applying state-of-the-art signal features and machine-learning algorithms is possible. PMID:25977804

  10. Iron Oxide-labeled Collagen Scaffolds for Non-invasive MR Imaging in Tissue Engineering

    PubMed Central

    Mertens, Marianne E.; Hermann, Alina; Bühren, Anne; Olde-Damink, Leon; Möckel, Diana; Gremse, Felix; Ehling, Josef; Kiessling, Fabian; Lammers, Twan

    2013-01-01

    Non-invasive imaging holds significant potential for implementation in tissue engineering. It can e.g. be used to monitor the localization and function of tissue-engineered implants, as well as their resorption and remodelling. Thus far, however, the vast majority of efforts in this area of research have focused on the use of ultrasmall super-paramagnetic iron oxide (USPIO) nanoparticle-labeled cells, colonizing the scaffolds, to indirectly image the implant material. Reasoning that directly labeling scaffold materials might be more beneficial (enabling imaging also in case of non-cellularized implants), more informative (enabling the non-invasive visualization and quantification of scaffold degradation) and more easy to translate into the clinic (since cell-free materials are less complex from a regulatory point-of-view), we here prepared three different types of USPIO nanoparticles, and incorporated them both passively and actively (via chemical conjugation; during collagen crosslinking) into collagen-based scaffold materials. We furthermore optimized the amount of USPIO incorporated into the scaffolds, correlated the amount of entrapped USPIO with MR signal intensity, showed that the labeled scaffolds are highly biocompatible, demonstrated that scaffold degradation can be visualized using MRI and provided initial proof-of-principle for the in vivo visualization of the scaffolds. Consequently, USPIO-labeled scaffold materials seem to be highly suitable for image-guided tissue engineering applications. PMID:24569840

  11. Invasive clonal plant species have a greater root-foraging plasticity than non-invasive ones.

    PubMed

    Keser, Lidewij H; Dawson, Wayne; Song, Yao-Bin; Yu, Fei-Hai; Fischer, Markus; Dong, Ming; van Kleunen, Mark

    2014-03-01

    Clonality is frequently positively correlated with plant invasiveness, but which aspects of clonality make some clonal species more invasive than others is not known. Due to their spreading growth form, clonal plants are likely to experience spatial heterogeneity in nutrient availability. Plasticity in allocation of biomass to clonal growth organs and roots may allow these plants to forage for high-nutrient patches. We investigated whether this foraging response is stronger in species that have become invasive than in species that have not. We used six confamilial pairs of native European clonal plant species differing in invasion success in the USA. We grew all species in large pots under homogeneous or heterogeneous nutrient conditions in a greenhouse, and compared their nutrient-foraging response and performance. Neither invasive nor non-invasive species showed significant foraging responses to heterogeneity in clonal growth organ biomass or in aboveground biomass of clonal offspring. Invasive species had, however, a greater positive foraging response in terms of root and belowground biomass than non-invasive species. Invasive species also produced more total biomass. Our results suggest that the ability for strong root foraging is among the characteristics promoting invasiveness in clonal plants. PMID:24352844

  12. Non-invasive detection of fatty liver in dairy cows by digital analyses of hepatic ultrasonograms.

    PubMed

    Bobe, Gerd; Amin, Viren R; Hippen, Arnold R; She, Pengxiang; Young, Jerry W; Beitz, Donald C

    2008-02-01

    During early lactation, many dairy cows develop fatty liver, which is associated with decreased health and reproductive performance. Currently, fatty liver can be detected reliably only by using liver biopsy followed by chemical or histological analysis, which is not practical in most on-farm situations. We tested whether digital analyses of hepatic ultrasonograms can be used to detect non-invasively fatty liver and estimate liver triacylglycerol content. A total of 49 liver biopsies and ultrasonograms were taken from 29 dairy cows within 2 weeks postpartum. The usefulness of 17 first- or second-order parameters from digital analysis of B-mode ultrasonograms were evaluated by discriminant, correlation, and regression analyses. A group of linear combinations of the 17 parameters correctly classified 40 of 49 samples into normal liver as well as mild, moderate and severe fatty liver when cut-off values were 1%, 5% and 10% and correctly classified 45 of 49 samples when cut-off values were 5% and 10% triacylglycerol of wet weight. A linear combination of 16 image parameters estimated triacylglycerol concentrations of 38 of the 39 liver samples below the cut-off value of 10% within 2.5% of liver wet weight, and a linear combination of 3 parameters estimated triacylglycerol concentrations of the 10 liver samples above the cut-off value of 10% within 2% of liver wet weight. Therefore, ultrasound imaging followed by digital analysis of sonograms has potential to non-invasively detect fatty liver and estimate liver triacylglycerol content.

  13. Potential of non-invasive esophagus cancer detection based on urine surface-enhanced Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Huang, Shaohua; Wang, Lan; Chen, Weisheng; Feng, Shangyuan; Lin, Juqiang; Huang, Zufang; Chen, Guannan; Li, Buhong; Chen, Rong

    2014-11-01

    Non-invasive esophagus cancer detection based on urine surface-enhanced Raman spectroscopy (SERS) analysis was presented. Urine SERS spectra were measured on esophagus cancer patients (n = 56) and healthy volunteers (n = 36) for control analysis. Tentative assignments of the urine SERS spectra indicated some interesting esophagus cancer-specific biomolecular changes, including a decrease in the relative content of urea and an increase in the percentage of uric acid in the urine of esophagus cancer patients compared to that of healthy subjects. Principal component analysis (PCA) combined with linear discriminant analysis (LDA) was employed to analyze and differentiate the SERS spectra between normal and esophagus cancer urine. The diagnostic algorithms utilizing a multivariate analysis method achieved a diagnostic sensitivity of 89.3% and specificity of 83.3% for separating esophagus cancer samples from normal urine samples. These results from the explorative work suggested that silver nano particle-based urine SERS analysis coupled with PCA-LDA multivariate analysis has potential for non-invasive detection of esophagus cancer.

  14. Non-invasive assessment of liver fibrosis in patients with alcoholic liver disease.

    PubMed

    Lombardi, Rosa; Buzzetti, Elena; Roccarina, Davide; Tsochatzis, Emmanuel A

    2015-10-21

    Alcoholic liver disease (ALD) consists of a broad spectrum of disorders, ranging from simple steatosis to alcoholic steatohepatitis and cirrhosis. Fatty liver develops in more than 90% of heavy drinkers, however only 30%-35% of them develop more advanced forms of ALD. Therefore, even if the current "gold standard" for the assessment of the stage of alcohol-related liver injury is histology, liver biopsy is not reasonable in all patients who present with ALD. Currently, although several non-invasive fibrosis markers have been suggested as alternatives to liver biopsy in patients with ALD, none has been sufficiently validated. As described in other liver disease, the diagnostic accuracy of such tests in ALD is acceptable for the diagnosis of significant fibrosis or cirrhosis but not for lesser fibrosis stages. Existing data suggest that the use of non-invasive tests could be tailored to first tier screening of patients at risk, in order to diagnose early patients with progressive liver disease and offer targeted interventions for the prevention of decompensation. We review these tests and critically appraise the existing evidence.

  15. The Role of Infrared Thermography as a Non-Invasive Tool for the Detection of Lameness in Cattle

    PubMed Central

    Alsaaod, Maher; Schaefer, Allan L.; Büscher, Wolfgang; Steiner, Adrian

    2015-01-01

    The use of infrared thermography for the identification of lameness in cattle has increased in recent years largely because of its non-invasive properties, ease of automation and continued cost reductions. Thermography can be used to identify and determine thermal abnormalities in animals by characterizing an increase or decrease in the surface temperature of their skin. The variation in superficial thermal patterns resulting from changes in blood flow in particular can be used to detect inflammation or injury associated with conditions such as foot lesions. Thermography has been used not only as a diagnostic tool, but also to evaluate routine farm management. Since 2000, 14 peer reviewed papers which discuss the assessment of thermography to identify and manage lameness in cattle have been published. There was a large difference in thermography performance in these reported studies. However, thermography was demonstrated to have utility for the detection of contralateral temperature difference and maximum foot temperature on areas of interest. Also apparent in these publications was that a controlled environment is an important issue that should be considered before image scanning. PMID:26094632

  16. Assessment of a non-invasive high-throughput classifier for behaviours associated with sleep and wake in mice

    PubMed Central

    Donohue, Kevin D; Medonza, Dharshan C; Crane, Eli R; O'Hara, Bruce F

    2008-01-01

    This work presents a non-invasive high-throughput system for automatically detecting characteristic behaviours in mice over extended periods of time, useful for phenotyping experiments. The system classifies time intervals on the order of 2 to 4 seconds as corresponding to motions consistent with either active wake or inactivity associated with sleep. A single Polyvinylidine Difluoride (PVDF) sensor on the cage floor generates signals from motion resulting in pressure. This paper develops a linear classifier based on robust features extracted from normalized power spectra and autocorrelation functions, as well as novel features from the collapsed average (autocorrelation of complex spectrum), which characterize transient and periodic properties of the signal envelope. Performance is analyzed through an experiment comparing results from direct human observation and classification of the different behaviours with an automatic classifier used in conjunction with this system. Experimental results from over 28.5 hours of data from 4 mice indicate a 94% classification rate relative to the human observations. Examples of sequential classifications (2 second increments) over transition regions between sleep and wake behaviour are also presented to demonstrate robust performance to signal variation and explain performance limitations. PMID:18405376

  17. Multiparametric Functional MRI: Non-Invasive Imaging of Inflammation and Edema Formation after Kidney Transplantation in Mice

    PubMed Central

    Gutberlet, Marcel; Bräsen, Jan Hinrich; Jang, Mi-Sun; Thorenz, Anja; Chen, Rongjun; Hertel, Barbara; Barrmeyer, Amelie; Schmidbauer, Martina; Meier, Martin; von Vietinghoff, Sibylle; Khalifa, Abedalrazag; Hartung, Dagmar; Haller, Hermann; Wacker, Frank

    2016-01-01

    Background Kidney transplantation (ktx) in mice is used to learn about rejection and to develop new treatment strategies. Past studies have mainly been based on histological or molecular biological methods. Imaging techniques to monitor allograft pathology have rarely been used. Methods Here we investigated mice after isogenic and allogenic ktx over time with functional MRI with diffusion-weighted imaging (DWI) and mapping of T2-relaxation time (T2-mapping) to assess graft inflammation and edema formation. To characterize graft pathology, we used PAS-staining, counted CD3-positive T-lymphocytes, analyzed leukocytes by means flow cytometry. Results DWI revealed progressive restriction of diffusion of water molecules in allogenic kidney grafts. This was paralleled by enhanced infiltration of the kidney by inflammatory cells. Changes in tissue diffusion were not seen following isogenic ktx. T2-times in renal cortex were increased after both isogenic and allogenic transplantation, consistent with tissue edema due to ischemic injury following prolonged cold ischemia time of 60 minutes. Lack of T2 increase in the inner stripe of the inner medulla in allogenic kidney grafts matched loss of tubular autofluorescence and may result from rejection-driven reductions in tubular water content due to tubular dysfunction and renal functional impairment. Conclusions Functional MRI is a valuable non-invasive technique for monitoring inflammation, tissue edema and tubular function. It permits on to differentiate between acute rejection and ischemic renal injury in a mouse model of ktx. PMID:27632553

  18. Optical coherence elastography for tissue characterization: a review.

    PubMed

    Wang, Shang; Larin, Kirill V

    2015-04-01

    Optical coherence elastography (OCE) represents the frontier of optical elasticity imaging techniques and focuses on the micro-scale assessment of tissue biomechanics in 3D that is hard to achieve with traditional elastographic methods. Benefit from the advancement of optical coherence tomography, and driven by the increasing requirements in nondestructive biomechanical characterization, this emerging technique recently has experienced a rapid development. In this paper, we start with the description of the mechanical contrast that has been employed by OCE and review the state-of-the-art techniques based on the reported applications and discuss the current technical challenges, emphasizing the unique role of OCE in tissue mechanical characterization. The position of OCE among other elastography techniques.

  19. Improved control and characterization of adjustable x-ray optics

    NASA Astrophysics Data System (ADS)

    Allured, Ryan; Ben-Ami, Sagi; Cotroneo, Vincenzo; Marquez, Vanessa; McMuldroch, Stuart; Reid, Paul B.; Schwartz, Daniel A.; Trolier-McKinstry, Susan; Vikhlinin, Alexey A.; Wallace, Margeaux L.

    2015-09-01

    We report on improvements in our efforts to control and characterize piezoelectrically adjustable, thin glass optics. In the past, an optical profilometer and a Shack-Hartmann wavefront sensor have been used to measure influence functions for a at adjustable mirror. An electronics system has since been developed to control > 100 actuator cells and has been used in a full calibration of a high-yield at adjustable mirror. The calibrated influence functions have been used to induce a pre-determined figure change to the mirror, representing our first attempt at figure control of a full mirror. Furthermore, we have adapted our metrology systems for cylindrical optics, allowing characterization of Wolter-type mirrors. We plan to use this metrology to perform the first piezoelectric figure correction of a cylindrical mirror over the next year.

  20. Optical coherence elastography for tissue characterization: a review

    PubMed Central

    Wang, Shang; Larin, Kirill V.

    2015-01-01

    Optical coherence elastography (OCE) represents the frontier of optical elasticity imaging techniques and focuses on the micro-scale assessment of tissue biomechanics in 3D that is hard to achieve with traditional elastographic methods. Benefit from the advancement of optical coherence tomography, and driven by the increasing requirements in nondestructive biomechanical characterization, this emerging technique recently has experienced a rapid development. In this paper, we start with the description of the mechanical contrast that has been employed by OCE and review the state-of-the-art techniques based on the reported applications and discuss the current technical challenges, emphasizing the unique role of OCE in tissue mechanical characterization. The position of OCE among other elastography techniques. PMID:25412100