WorldWideScience

Sample records for gases combined imaging

  1. Imaging of ionizing radiations from electronic avalanches, limited, in gases

    International Nuclear Information System (INIS)

    Charpak, G.

    1995-01-01

    This work deals with the imaging of ionizing radiations from electronic avalanches in gases. Some applications realized with the help of physical instruments like : fog chambers, Geiger-Mueller counters, proportional counters, scintillation counters, semiconductor detectors, nuclear emulsions, bubble chambers, drift chambers, wire spark chambers and calorimeters are described and their performances compared. (O.L.). 5 refs., 10 figs

  2. ''Inhalation lung imaging with radioactive aerosols and gases''

    International Nuclear Information System (INIS)

    Taplin, G.V.; Chopra, S.K.

    1977-01-01

    Lung imaging procedures, performed after the inhalation of /sup 99m/Tc labeled aerosols, 133 Xe and /sup 81m/Kr gases, were used to visualize the sites of airway obstruction and regional abnormalities of ventilatory function in normal volunteers, patients with obstructive airway disease, and pulmonary embolism suspects. Comparisons were made of three methods regarding their functional significance, diagnostic merits, and limitations. A new nebulizer-radioaerosol delivery system is described

  3. Field-portable imaging remote sensing system for automatic identification and imaging of hazardous gases

    Science.gov (United States)

    Harig, R.; Rusch, P.; Peters, H.; Gerhard, J.; Braun, R.,; Sabbah, S.; Beecken, J.

    2009-09-01

    Hazardous compounds may be released into the atmosphere in the case of fires, chemical accidents, terrorist acts, or war. In these cases, information about the released compounds is required immediately in order to take appropriate measures to protect workers, residents, emergency response personnel at the site of the release, and the environment. Remote sensing by infrared spectroscopy allows detection and identification of hazardous clouds in the atmosphere from long distances. In addition, imaging spectroscopy allows an assessment of the location, the dimensions and the dispersion of a potentially hazardous cloud. This additional information may contribute significantly to a correct assessment of a situation by emergency response forces. Therefore an imaging remote sensing system based on a Fourier-transform spectrometer with a focal plane array detector for automatic identification and imaging of gases has been developed. Imaging systems allow the use of spatial information in addition to spectral information. Thus, in order to achieve low limits of detection, algorithms that combine algorithms for spectral analysis and image analysis have been developed. In this work, the system and first results of measurements are presented.

  4. Emissions of ammonia and greenhouse gases during combined pre-composting and vermicomposting of duck manure.

    Science.gov (United States)

    Wang, Jinzhi; Hu, Zhengyi; Xu, Xingkai; Jiang, Xia; Zheng, Binghui; Liu, Xiaoning; Pan, Xubin; Kardol, Paul

    2014-08-01

    Combined pre-composting and vermicomposting has shown potential for reclamation of solid wastes, which is a significant source of ammonia (NH3), and greenhouse gases (GHG), including nitrous oxide (N2O), methane (CH4), and carbon dioxide (CO2). Earthworms and amendments may both affect physico-chemical characteristics that control gas-producing processes, and thus affect NH3 and GHG emissions. Here, we used two-way ANOVA to test the effects of addition of reed straw and combined addition of reed straw and zeolite on NH3 and GHG emissions during pre-composting of duck manure, either with or without a follow-up phase of vermicomposting. Results showed that cumulative N2O, CH4, and CO2 emissions during pre-composting and vermicomposting ranged from 92.8, 5.8, and 260.6 mg kg(-)(1) DM to 274.2, 30.4, and 314.0 mg kg(-1) DM, respectively. Earthworms and amendments significantly decreased N2O and CH4 emissions. Emission of CO2 was not affected by earthworms, but increased in responses to addition of reed straw. Cumulative NH3 emission ranged from 3.0 to 8.1 g kg(-1) DM, and was significantly decreased by reed straw and zeolite addition. In conclusion, combined pre-composting and vermicomposting with reed straw and zeolite addition would be strongly recommended in mitigating emissions of N2O, CH4, and NH3 from duck manure. Moreover, this method also provides nutrient-rich products that can be used as a fertilizer. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Emissions of ammonia and greenhouse gases during combined pre-composting and vermicomposting of duck manure

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jinzhi [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environment Sciences, Beijing 100012 (China); College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049 (China); Hu, Zhengyi, E-mail: zhyhu@ucas.ac.cn [College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049 (China); Xu, Xingkai [State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029 (China); Jiang, Xia; Zheng, Binghui [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environment Sciences, Beijing 100012 (China); Liu, Xiaoning [College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049 (China); Pan, Xubin [Institute of Plant Quarantine, Chinese Academy of Inspection and Quarantine, Beijing 100029 (China); Kardol, Paul [Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, S 90183 Umeå (Sweden)

    2014-08-15

    Highlights: • Earthworms significantly decreased emissions of N{sub 2}O and CH{sub 4}, but had a marginal effect on CO{sub 2} emission. • NH{sub 3}, N{sub 2}O, and CH{sub 4} emissions were significantly reduced by reed straw and zeolite, CO{sub 2} emission was increased by reed straw. • Combined pre-composting and vermicomposting with reed straw and zeolite would be recommended for disposal of duck manure. - Abstract: Combined pre-composting and vermicomposting has shown potential for reclamation of solid wastes, which is a significant source of ammonia (NH{sub 3}), and greenhouse gases (GHG), including nitrous oxide (N{sub 2}O), methane (CH{sub 4}), and carbon dioxide (CO{sub 2}). Earthworms and amendments may both affect physico-chemical characteristics that control gas-producing processes, and thus affect NH{sub 3} and GHG emissions. Here, we used two-way ANOVA to test the effects of addition of reed straw and combined addition of reed straw and zeolite on NH{sub 3} and GHG emissions during pre-composting of duck manure, either with or without a follow-up phase of vermicomposting. Results showed that cumulative N{sub 2}O, CH{sub 4}, and CO{sub 2} emissions during pre-composting and vermicomposting ranged from 92.8, 5.8, and 260.6 mg kg{sup −1} DM to 274.2, 30.4, and 314.0 mg kg{sup −1} DM, respectively. Earthworms and amendments significantly decreased N{sub 2}O and CH{sub 4} emissions. Emission of CO{sub 2} was not affected by earthworms, but increased in responses to addition of reed straw. Cumulative NH{sub 3} emission ranged from 3.0 to 8.1 g kg{sup −1} DM, and was significantly decreased by reed straw and zeolite addition. In conclusion, combined pre-composting and vermicomposting with reed straw and zeolite addition would be strongly recommended in mitigating emissions of N{sub 2}O, CH{sub 4}, and NH{sub 3} from duck manure. Moreover, this method also provides nutrient-rich products that can be used as a fertilizer.

  6. Recent developments in combining LODESR imaging with proton NMR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Nicholson, I.; Robb, F.J.L.; McCallum, S.J.; Koptioug, A.; Lurie, D.J. [Department of Biomedical Physics and Bioengineering, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD (United Kingdom)

    1998-07-01

    We have designed and constructed RF coil assemblies and the appropriate instrumentation for combining proton NMR imaging with LODESR imaging. This has enabled us to collect sequential images from the same sample using both methods. The coil assembly consists of a crossed ellipse coil for LODESR and proton NMR signal detection and a saddle coil for excitation of the ESR resonance. Images have been collected of phantoms containing copper sulphate and Tempol solutions. NMR images were collected (4.3 min) and within 30 s LODESR data collection started (collection time 2.5 min). Only the Tempol solutions are visible in the LODESR images. (author)

  7. Seeing double: combined modalities in functional imaging

    Energy Technology Data Exchange (ETDEWEB)

    Del Guerra, A. E-mail: delguerra@pi.infn.it; Damiani, C.; Di Domenico, G.; Gambaccini, M.; Motta, A.; Sabba, N.; Zavattini, G

    2001-09-21

    Various dedicated instruments for combined modalities in functional imaging are being developed by our group: a small animal PET/SPECT scanner, two scintimammography apparatus for breast cancer diagnosis, one with RX/PEM and the other with RX/SPECT capability. The performance and the status of development of these devices will be reported.

  8. Assessment of Burned Area and Atmospheric Gases from Multi- temporal MODIS Images (2000- 2017) in Nainital District, Uttarakhand

    Science.gov (United States)

    Aggarwal, R.; K V, S. B.; Dhakate, P. M.

    2017-12-01

    Recent times have observed a significant rate of deforestation and forest degradation. One of the major causes of forest degradation is forest fires. Forest fires though have shaped the current forest ecosystem but also have continued to degrade the system by causing loss of flora and fauna. In addition to that, forest fire leads to emission of carbon and other trace gases which contributes to global warming. The hill states in India, particularly Uttarakhand witnesses annual forest fires; which are primarily anthropogenic caused, occurring from March to June. Nainital one of the thirteen districts in Uttarakhand, has been selected as the study site. The region has diverse endemic species of vegetation, ranging from Alpine in North to moist deciduous in South. The increasing forest fire incidents in the region and limited studies on the subject, calls for landscape assessment of the complex Human Environment System (HES). It is in this context, that a greater need for monitoring forest fire incidents has been felt. Remote Sensing and GIS which are robust tool, provides continuous information of an area at various spatial and temporal resolutions. The goal of this study is to map burned area, burned severity and estimate atmospheric gas emissions in forested areas of Nainital by utilizing cloud free MODIS images from 2000- 2017. Multiple spectral indices were generated from pre and post burn dataset of MODIS to conclude the most sensitive band combination. Inter- comparison of results obtained from different spectral indices and the global MODIS MCD45A1 was carried out using linear regression analysis. Additionally, burned area estimation from satellite was compared to figures reported by forest department. There were considerable differences amongst the two which could be primarily due to differences in spatial resolution, and timings of forest fire occurrence and image acquisition. Further, estimation of various atmospheric gases was carried out based on the IPCC

  9. Combined PET/MR imaging in neurology

    DEFF Research Database (Denmark)

    Andersen, Flemming Littrup; Ladefoged, Claes Nøhr; Beyer, Thomas

    2014-01-01

    on a transaxial T1w-MR image traversing the central basal ganglia. We report the relative difference (%) of the mean ROI values for (A)-(C) in reference to PET/CT (D). In a separate phantom experiment a 2L plastic bottle was layered with approximately 12mm of Gypsum plaster to mimic skull bone. The phantom......AIM: Combined PET/MR systems have now become available for clinical use. Given the lack of integrated standard transmission (TX) sources in these systems, attenuation and scatter correction (AC) must be performed using the available MR-images. Since bone tissue cannot easily be accounted for during...... MR-AC, PET quantification can be biased, in particular, in the vicinity of the skull. Here, we assess PET quantification in PET/MR imaging of patients using phantoms and patient data. MATERIALS AND METHODS: Nineteen patients referred to our clinic for a PET/CT exam as part of the diagnostic...

  10. Simultaneous control of acid gases and PAHs using a spray dryer combined with a fabric filter using different additives.

    Science.gov (United States)

    Liu, Zhen Shu; Wey, Ming Yen; Lin, Chiou Liang

    2002-04-26

    The purpose of this research was to simultaneously evaluate the removal efficiency of acid gases and PAHs from the flue gas emitted by a laboratory incinerator. This flue gas contained dust, acid gases, organics and heavy metals. A spray dryer combined with a fabric filter was used as the air pollution control device (APCD) in this study. The operating conditions investigated included different feedstock additives (polyvinyl chloride (PVC) and NaCl) and spray dryer additives (SiO2, CaCl2 and NaHCO3). The removal efficiency for SO2 could be enhanced by adding inorganic additives, such as SiO2, CaCl2 and NaHCO3. The presence of PVC in the incinerator feedstock also increased the removal efficiency of SO2in the spray dryer. The improved removal of PAHs could be attributed to the addition of feedstock additives (PVC and NaCl) and spray dryer additives (SiO2, CaCl2 and NaHCO3).

  11. Comparative Studies on Methane Upgradation of Biogas by Removing of Contaminant Gases Using Combined Chemical Methods

    Directory of Open Access Journals (Sweden)

    Muhammad Rashed Al Mamun

    2015-07-01

    Full Text Available Biogas, which generated from renewable sources can be used as a sustainable energy to achieve resourceful targets of biofuel for internal combustion engines. This process can be achieved in combined absorption and adsorption chemical way. This method can be employed by aqueous solutions of calcium hydroxide, activated carbon, iron(II chloride, silica gel and sodium sulfate respectively. The presence of CO2, H2S and H2O in the biogas has lowering the calorific value and detrimental corrosion effects on the metal components. Removal of these contaminants from the biogas can therefore significantly improve the gas quality. A comparison study was investigated using combined chemical methods of improving the calorific value of biogas. Experiment results revealed that the aqueous solution used effectively in reacting with CO2 in biogas (over 85-90% removal efficiency, creating CH4 enriched biogas. The removal efficiency was the highest in method 1, where efficiency results were 91.5%, 97.1% and 91.8%, for CO2, H2S, and H2O, respectively. The corresponding CH4 enrichment was 97.5%. These results indicate that the method 1 is more suitable compare to method 2. However, both methane enrichment processes might be useful for cleaning and upgrading methane quality in biogas.

  12. Multi-layer Retrievals of Greenhouse Gases from a Combined Use of GOSAT TANSO-FTS SWIR and TIR

    Science.gov (United States)

    Kikuchi, N.; Kuze, A.; Kataoka, F.; Shiomi, K.; Hashimoto, M.; Suto, H.; Knuteson, R. O.; Iraci, L. T.; Yates, E. L.; Gore, W.; Tanaka, T.; Yokota, T.

    2016-12-01

    The TANSO-FTS sensor onboard GOSAT has three frequency bands in the shortwave infrared (SWIR) and the fourth band in the thermal infrared (TIR). Observations of high-resolution spectra of reflected sunlight in the SWIR are extensively utilized to retrieve column-averaged concentrations of the major greenhouse gases such as carbon dioxide (XCO2) and methane (XCH4). Although global XCO2 and XCH4 distribution retrieved from SWIR data can reduce the uncertainty in the current knowledge about sources and sinks of these gases, information on the vertical profiles would be more useful to constrain the surface flux and also to identify the local emission sources. Based on the degrees of freedom for signal, Kulawik et al. (2016, IWGGMS-12 presentation) shows that 2-layer information on the concentration of CO2 can be extracted from TANSO-FTS SWIR measurements, and the retrieval error is predicted to be about 5 ppm in the lower troposphere. In this study, we present multi-layer retrievals of CO2 and CH4 from a combined use of measurements of TANSO-FTS SWIR and TIR. We selected GOSAT observations at Railroad Valley Playa in Nevada, USA, which is a vicarious calibration site for TANSO-FTS, as we have various ancillary data including atmospheric temperature and humidity taken by a radiosonde, surface temperature, and surface emissivity with a ground based FTS. All of these data are useful especially for retrievals using TIR spectra. Currently, we use the 700-800 cm-1 and 1200-1300 cm-1 TIR windows for CO2 and CH4 retrievals, respectively, in addition to the SWIR bands. We found that by adding TIR windows, 3-layer information can be extracted, and the predicted retrieval error in the CO2 concentration was reduced about 1 ppm in the lower troposphere. We expect that the retrieval error could be further reduced by optimizing TIR windows and by reducing systematic forward model errors.

  13. Industrial gases

    International Nuclear Information System (INIS)

    Hunter, D.; Jackson, D.; Coeyman, M.

    1993-01-01

    Industrial gas companies have fought hard to boost sales and hold margins in the tough economic climate, and investments are well down from their 1989-'91 peak. But 'our industry is still very strong long term' says Alain Joly, CEO of industry leader L'Air Liquide (AL). By 1994, if a European and Japanese recovery follows through on one in the U.S., 'we could see major [investment] commitments starting again,' he says. 'Noncryogenic production technology is lowering the cost of gas-making possible new applications, oxygen is getting plenty of attention in the environmental area, and hydrogen also fits into the environmental thrust,' says Bob Lovett, executive v.p./gases and equipment with Air Products ampersand Chemicals (AP). Through the 1990's, 'Industrial gases could grow even faster than in the past decade,' he says. Virtually a new generation of new gases applications should become reality by the mid-1990s, says John Campbell, of industry consultants J.R. Campbell ampersand Associates (Lexington, MA). Big new oxygen volumes will be required for powder coal injection in blast furnaces-boosting a steel mill's requirement as much as 40% and coal gasification/combined cycle (CGCC). Increased oil refinery hydroprocessing needs promise hydrogen requirements

  14. Mixtures of relativistic gases in gravitational fields: Combined Chapman-Enskog and Grad method and the Onsager relations.

    Science.gov (United States)

    Moratto, Valdemar; Kremer, Gilberto M

    2015-05-01

    In this work we study an r-species mixture of gases within the relativistic kinetic theory point of view. We use the relativistic covariant Boltzmann equation and incorporate the Schwarzschild metric. The method of solution of the Boltzmann equation is a combination of the Chapman-Enskog and Grad representations. The thermodynamic four-fluxes are expressed as functions of the thermodynamic forces so the generalized expressions for the Navier-Stokes, Fick, and Fourier laws are obtained. The constitutive equations for the diffusion and heat four-fluxes of the mixture are functions of thermal and diffusion generalized forces which depend on the acceleration and the gravitational potential gradient. While this dependence is of relativistic nature for the thermal force, this is not the case for the diffusion forces. We show also that the matrix of diffusion coefficients is symmetric, implying that the thermal-diffusion equals the diffusion-thermal effect, proving the Onsager reciprocity relations. The entropy four-flow of the mixture is also expressed in terms of the thermal and diffusion generalized forces, so its dependence on the acceleration and gravitational potential gradient is also determined.

  15. An Effective Combined Feature For Web Based Image Retrieval

    Directory of Open Access Journals (Sweden)

    H.M.R.B Herath

    2015-08-01

    Full Text Available Abstract Technology advances as well as the emergence of large scale multimedia applications and the revolution of the World Wide Web has changed the world into a digital age. Anybody can use their mobile phone to take a photo at any time anywhere and upload that image to ever growing image databases. Development of effective techniques for visual and multimedia retrieval systems is one of the most challenging and important directions of the future research. This paper proposes an effective combined feature for web based image retrieval. Frequently used colour and texture features are explored in order to develop a combined feature for this purpose. Widely used three colour features Colour moments Colour coherence vector and Colour Correlogram and three texture features Grey Level Co-occurrence matrix Tamura features and Gabor filter were analyzed for their performance. Precision and Recall were used to evaluate the performance of each of these techniques. By comparing precision and recall values the methods that performed best were taken and combined to form a hybrid feature. The developed combined feature was evaluated by developing a web based CBIR system. A web crawler was used to first crawl through Web sites and images found in those sites are downloaded and the combined feature representation technique was used to extract image features. The test results indicated that this web system can be used to index web images with the combined feature representation schema and to find similar images. Random image retrievals using the web system shows that the combined feature can be used to retrieve images belonging to the general image domain. Accuracy of the retrieval can be noted high for natural images like outdoor scenes images of flowers etc. Also images which have a similar colour and texture distribution were retrieved as similar even though the images were belonging to deferent semantic categories. This can be ideal for an artist who wants

  16. Electronegative gases

    International Nuclear Information System (INIS)

    Christophorou, L.G.

    1981-01-01

    Recent knowledge on electronegative gases essential for the effective control of the number densities of free electrons in electrically stressed gases is highlighted. This knowledge aided the discovery of new gas dielectrics and the tailoring of gas dielectric mixtures. The role of electron attachment in the choice of unitary gas dielectrics or electronegative components in dielectric gas mixtures, and the role of electron scattering at low energies in the choice of buffer gases for such mixtures is outlined

  17. Evaluation of Different Gases and Gas Combinations for On-Farm Euthanasia of Pre-Weaned Pigs

    Directory of Open Access Journals (Sweden)

    Nikki Kells

    2018-03-01

    Full Text Available The aim of this research was to evaluate the welfare of pre-weaned piglets euthanised using three different gas treatments: 100% carbon dioxide (CO2, 100% argon (Ar or a mixture of 60% Ar/40% carbon dioxide (Ar/CO2. Two studies (n = 5 piglets/treatment/study were conducted: (1 behavioural and physiological data were collected from conscious piglets during exposure to test gases via immersion in a pre-filled chamber and (2 electrophysiological data were collected from lightly anaesthetised, intubated and mechanically ventilated piglets exposed to the same test gases. Based on the duration of escape attempts and laboured breathing, piglets exposed to 100% CO2 experienced more stress than piglets exposed to 100% Ar prior to loss of consciousness, but there appeared to be no advantage of mixing Ar with CO2 on indices of animal welfare. However, spectral analysis of the electroencephalogram revealed no changes consistent with nociception during exposure to any of the three gas treatments. Based on the behavioural response to gas exposure, all gases tested caused signs of stress prior to piglets losing consciousness and hence alternative methods of euthanasia need to be evaluated.

  18. DAVINCI: Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging

    Science.gov (United States)

    Glaze, Lori S.; Garvin, James B.; Robertson, Brent; Johnson, Natasha M.; Amato, Michael J.; Thompson, Jessica; Goodloe, Colby; Everette, Dave

    2017-01-01

    DAVINCI is one of five Discovery-class missions selected by NASA in October 2015 for Phase A studies. Launching in November 2021 and arriving at Venus in June of 2023, DAVINCI would be the first U.S. entry probe to target Venus atmosphere in 45 years. DAVINCI is designed to study the chemical and isotopic composition of a complete cross-section of Venus atmosphere at a level of detail that has not been possible on earlier missions and to image the surface at optical wavelengths and process-relevant scales.

  19. Combined distiller waste utilisation and combustion gases desulphurisation method. The case study of soda-ash industry

    Energy Technology Data Exchange (ETDEWEB)

    Kasikowski, Tomasz; Buczkowski, Roman; Cichosz, Marcin; Lemanowska, Eliza [Faculty of Chemistry, Nicolas Copernicus University, ul. Gagarina 7, 87-100 Torun (Poland)

    2007-09-15

    In this paper, a concept of technology that can be helpful for lowering the negative influence of the synthetic (based on the Solvay process) soda ash plant on the natural environment is presented. We describe the desulphurisation of combustion gases from the factory's power plant, which is based on their absorption in the overflow of distiller waste. The excess of lime milk, which is added in the process of ammonia regeneration from filter liquor, results in a strong alkalinity of distiller waste. The high pH of distiller waste favours absorption of acidic combustion gases. The laboratory-scale tests showed about 80% efficiency of the desulphurisation process. The suspension samples we obtained consist mainly of CaCO{sub 3}. We suggest using the obtained solid phase as an adsorbent-insert in Fluidised Bed Combustion technology (FBC). Based on raw material prices, production costs, and average sell prices of the product, economic analysis of innovation was executed. Profits from employing the method presented come mainly from reduction of environmental fees. The sensitivity analysis of cost showed that the application of the desulphurisation process causes cost reduction in soda-ash production accounting for EUR 150 thousand per year (excluding depreciation) in Poland, and EUR 11,700 thousand per year (excluding depreciation) in Sweden. It has been found that the latter value is similar to the positive environmental impact of this innovation expressed in monetary units (EUR 10,350 thousand per year, excluding depreciation). (author)

  20. Brain MRI tumor image fusion combined with Shearlet and wavelet

    Science.gov (United States)

    Zhang, Changjiang; Fang, Mingchao

    2017-11-01

    In order to extract the effective information in different modalities of the tumor region in brain Magnetic resonance imaging (MRI) images, we propose a brain MRI tumor image fusion method combined with Shearlet and wavelet transform. First, the source images are transformed into Shearlet domain and wavelet domain. Second, the low frequency component of Shearlet domain is fused by Laplace pyramid decomposition. Then the low-frequency fusion image is obtained through inverse Shearlet transform. Third, the high frequency subimages in wavelet domain are fused. Then the high-frequency fusion image is obtained through inverse wavelet transform. Finally, the low-frequency fusion image and high-frequency fusion image are summated to get the final fusion image. Through experiments conducted on 10 brain MRI tumor images, the result shown that the proposed fusion algorithm has the best fusion effect in the evaluation indexes of spatial frequency, edge strength and average gradient. The main spatial frequency of 10 images is 29.22, and the mean edge strength and average gradient is 103.77 and 10.42. Compared with different fusion methods, we find that the proposed method effectively fuses the information of multimodal brain MRI tumor images and improves the clarity of the tumor area well.

  1. Hyperthermia system working in combination with an MR imaging unit

    International Nuclear Information System (INIS)

    LeBihan, D.J.; Delannoy, J.; Levin, R.L.; Hoult, D.I.

    1988-01-01

    The authors propose a hyperthermia device to be used for temperature monitoring. It consists of a modified miniannular phased array (MAPA) radio-frequency applicator designed for limb tumor treatment that works in combination with a whole-body MR imaging unit operating at 21 MHz. Highly accurate (0.5 0 c/0.8 cm 2 ) temperature images are obtained noninvasively throughout the heated volume from MR images of molecular diffusion, the relation of which with temperature is well known. The MAPA, electrically modified to be compatible with MR imagers, can be centered inside the MR head coil. The combined system was tested on a phantom in which the temperature distribution was confirmed by miniature thermocouples

  2. Application unit for the administration of contrast gases for pulmonary magnetic resonance imaging: optimization of ventilation distribution for (3) He-MRI.

    Science.gov (United States)

    Güldner, M; Becker, St; Wolf, U; Düber, C; Friesenecker, A; Gast, K K; Heil, W; Hoffmann, C; Karpuk, S; Otten, E W; Rivoire, J; Salhi, Z; Scholz, A; Schreiber, L M; Terekhov, M

    2015-09-01

    MRI of lung airspaces using gases with MR-active nuclei ((3) He, (129) Xe, and (19) F) is an important area of research in pulmonary imaging. The volume-controlled administration of gas mixtures is important for obtaining quantitative information from MR images. State-of-the-art gas administration using plastic bags (PBs) does not allow for a precise determination of both the volume and timing of a (3) He bolus. A novel application unit (AU) was built according to the requirements of the German medical devices law. Integrated spirometers enable the monitoring of the inhaled gas flow. The device is particularly suited for hyperpolarized (HP) gases (e.g., storage and administration with minimal HP losses). The setup was tested in a clinical trial (n = 10 healthy volunteers) according to the German medicinal products law using static and dynamic ventilation HP-(3) He MRI. The required specifications for the AU were successfully realized. Compared to PB-administration, better reproducibility of gas intrapulmonary distribution was observed when using the AU for both static and dynamic ventilation imaging. The new AU meets the special requirements for HP gases, which are storage and administration with minimal losses. Our data suggest that gas AU-administration is superior to manual modes for determining the key parameters of dynamic ventilation measurements. © 2014 Wiley Periodicals, Inc.

  3. External dacryocystorhinostomy combined with mucosal grafting and magnetic resonance imaging

    International Nuclear Information System (INIS)

    Uehara, Fumiyuki; Ohba, Norio

    2002-01-01

    The purpose of this study was to facilitate understanding of the use of magnetic resonance imaging (MRI) in nasolacrimal obstructive diseases and to determine the indication for external dacryocystorhinostomy (DCR) combined with mucosal grafting. We retrospectively studied the correlation between MRI images and surgical findings in 13 consecutive patients with swollen lacrimal sacs because of obstruction of the nasolacrimal duct or lacrimal sac. They were treated at the Kagoshima University Hospital between June 1999 and May 2001. A simple procedure of external DCR was performed in 9 cases, and a procedure combined with mucosal grafting was performed in 4 cases (age range, 51-88 years). Surgical findings in the fibrous region of the lacrimal sac corresponded to the hyperintense signal on MRI T 1 -weighted (T1W) images, more remarkably after enhancement. Surgical findings in the granulomatous sac and proteinaceous contents corresponded to the isointense areas on T2W images. Cases with thin sac were treated by standard DCR, whereas cases with tick, fibrous and granulomatous sac were treated by external DCR combined with mucosal grafting. The MRI images provide a useful preoperative determination for indications of external DCR combined with mucosal grafting. (author)

  4. Combined radionuclide circulation and static imaging of the brain

    International Nuclear Information System (INIS)

    Kempi, V.; Ritter, B.; Scheele, C. von; Oestersund Hospital

    1980-01-01

    Combined static and dynamic imaging of the brain was performed in 398 patients with suspected space occupying lesions. The imaging findings were analyzed from two points of view: Firstly, the radionuclide results were compared with pathological anatomical findings and, secondly, the diagnostic yield in patients with various symptoms was evaluated. Thus we obtained the number of false positive and false negative results. The findings of the combined imaging procedure were correctly negative in 85% of the patients with non-focal symptoms and false positive in only 1%. The circultion study alone gave false positive results in 7% and so did the static study alone. The combined imaging procedure was pathologic in 46 of 83 cases of space-occupying lesions (55%). There were only three patients in whom a pathologic circulation study was the only indication of a space-occupying lesion (4%). The static study alone gave correct positive findings in 23 more cases (28%). We conclude that a pathologic blood flow study alone is of limited interest. In the presence of a pathologic static study the circulation procedure gives additional information, especially in meningioma and subdural hematoma. In patients with symptoms indicative of supratentorial space-occupying lesions of the brain combined imaging is recommended. (orig.) [de

  5. Greenhouse Gases

    Science.gov (United States)

    ... Precip, and Drought Climate at a Glance Extremes Societal Impacts Snow and Ice Teleconnections GHCN Monthly Monitoring References Introduction Water Vapor CO 2 CH 4 Ozone N 2 O CFCs CO Additional Information Introduction What are greenhouse gases? Many chemical compounds ...

  6. Irritant gases

    NARCIS (Netherlands)

    Meulenbelt, J

    Acute inhalation injury can result from the use of household cleaning agents (e.g. chlorine, ammonia), industrial or combustion gases (e.g. sulfur dioxide, nitrogen oxides) or bioterrorism. The severity of the injury is to a great extent determined by the circumstances of exposure. If exposure was

  7. Effect of combined digital imaging parameters on endodontic file measurements.

    Science.gov (United States)

    de Oliveira, Matheus Lima; Pinto, Geraldo Camilo de Souza; Ambrosano, Glaucia Maria Bovi; Tosoni, Guilherme Monteiro

    2012-10-01

    This study assessed the effect of the combination of a dedicated endodontic filter, spatial resolution, and contrast resolution on the determination of endodontic file lengths. Forty extracted single-rooted teeth were x-rayed with K-files (ISO size 10 and 15) in the root canals. Images were acquired using the VistaScan system (Dürr Dental, Beitigheim-Bissingen, Germany) under different combining parameters of spatial resolution (10 and 25 line pairs per millimeter [lp/mm]) and contrast resolution (8- and 16-bit depths). Subsequently, a dedicated endodontic filter was applied on the 16-bit images, creating 2 additional parameters. Six observers measured the length of the endodontic files in the root canals using the software that accompanies the system. The mean values of the actual file lengths and the measurements of the radiographic images were submitted to 1-way analysis of variance and the Tukey test at a level of significance of 5%. The intraobserver reproducibility was assessed by the intraclass correlation coefficient. All combined image parameters showed excellent intraobserver agreement with intraclass correlation coefficient means higher than 0.98. The imaging parameter of 25 lp/mm and 16 bit associated with the use of the endodontic filter did not differ significantly from the actual file lengths when both file sizes were analyzed together or separately (P > .05). When the size 15 file was evaluated separately, only 8-bit images differed significantly from the actual file lengths (P ≤ .05). The combination of an endodontic filter with high spatial resolution and high contrast resolution is recommended for the determination of file lengths when using storage phosphor plates. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  8. Infrared Image Segmentation by Combining Fractal Geometry with Wavelet Transformation

    Directory of Open Access Journals (Sweden)

    Xionggang Tu

    2014-11-01

    Full Text Available An infrared image is decomposed into three levels by discrete stationary wavelet transform (DSWT. Noise is reduced by wiener filter in the high resolution levels in the DSWT domain. Nonlinear gray transformation operation is used to enhance details in the low resolution levels in the DSWT domain. Enhanced infrared image is obtained by inverse DSWT. The enhanced infrared image is divided into many small blocks. The fractal dimensions of all the blocks are computed. Region of interest (ROI is extracted by combining all the blocks, which have similar fractal dimensions. ROI is segmented by global threshold method. The man-made objects are efficiently separated from the infrared image by the proposed method.

  9. Image averaging for angiography by registration and combination of serial images

    International Nuclear Information System (INIS)

    Brooks, S.H.; Selzer, R.H.; Crawford, D.W.; Blankenhorn, D.H.

    1982-01-01

    In order to increase the contrast of x-ray images of artery edges, a method is disclosed whereby a contrast medium opaque to x-rays in injected into a blood vessel distant from an artery section of interest. Mulitple x-ray images are obtained as the contrast medium and blood mixture flows through the artery section. These images are registered with a landmark within the patient. Density measurements are made with respect to each corresponding image segment and are combined to synthesize a composite image of the edge of the artery section

  10. Combination of acoustical radiosity and the image source method

    DEFF Research Database (Denmark)

    Koutsouris, Georgios I; Brunskog, Jonas; Jeong, Cheol-Ho

    2013-01-01

    A combined model for room acoustic predictions is developed, aiming to treat both diffuse and specular reflections in a unified way. Two established methods are incorporated: acoustical radiosity, accounting for the diffuse part, and the image source method, accounting for the specular part...... allows for a dynamic control of the image source production, so that no fixed maximum reflection order is required. The model is optimized for energy impulse response predictions in arbitrary polyhedral rooms. The predictions are validated by comparison with published measured data for a real music...

  11. Lattice gases

    International Nuclear Information System (INIS)

    Boghosian, B.M.

    1990-01-01

    In recent years an important class of cellular automata known as lattice gases have been successfully used to model a variety of physical systems, traditionally modeled by partial differential equations. The 2-D and 3-D Navier Stokes equations for single-phase and multiphase flow, Burgers' equation, and various types of diffusion equations are all examples. The first section of this chapter is meant to be a survey of the different ideas and techniques used in this simulations. In the second section, using lattice gases for the diffusion equation and for Burgers' equation as examples, the discrete Chapman-Enskog method is demonstrated. Beginning with rules governing particle motion on a lattice, the lattice Boltzmann equation is derived, and the Chapman-Enskog method is used to derive hydrodynamical equations for the conserved quantities. The approximations used at each step are discussed in detail. The intent is to provide an introduction to the Chapman-Enskog analysis for simple lattice gases in order to prepare the reader to better understand that for the (generally more complicated) models proposed for the simulation of the Navier-Stokes equations. 29 refs., 5 figs., 4 tabs

  12. Performance evaluation of atmospheric biomass integrated gasifier combined cycle systems under different strategies for the use of low calorific gases

    International Nuclear Information System (INIS)

    Rodrigues, Monica; Walter, Arnaldo; Faaij, Andre

    2007-01-01

    This work aims at a performance evaluation of atmospheric BIGCC (biomass integrated gasifier combined cycle) systems operating under different strategies for the use of low calorific fuel in gas turbines. The fuel is a synthetic gas derived from gasification of sugar cane residues. Two analysed strategies for surge control on gas turbines originally designed for operation on natural gas are de-rating and air extraction from the compressor. Another strategy for use of biomass derived gas is the retrofit of a gas turbine through modification of the expander geometry. Three generic gas turbines, whose main parameters have been taken from off the shelf machines, are proposed as representative of certain classes of gas turbines. Results are compared to the hypothetical situation in which it is possible to accept any increase in gas turbine pressure ratio. According to the results, de-rating is the worst surge control strategy, both from the point of view of power production and thermal efficiency. Conversely, results showed considerable gains that can be obtained on cycle power production when the gas turbine expander is modified. Additionally, an overview of issues concerning the suitability of sugar cane residues (bagasse and trash) for the production of gasified gas and its use in BIGCC plants is presented

  13. Global robust image rotation from combined weighted averaging

    Science.gov (United States)

    Reich, Martin; Yang, Michael Ying; Heipke, Christian

    2017-05-01

    In this paper we present a novel rotation averaging scheme as part of our global image orientation model. This model is based on homologous points in overlapping images and is robust against outliers. It is applicable to various kinds of image data and provides accurate initializations for a subsequent bundle adjustment. The computation of global rotations is a combined optimization scheme: First, rotations are estimated in a convex relaxed semidefinite program. Rotations are required to be in the convex hull of the rotation group SO (3) , which in most cases leads to correct rotations. Second, the estimation is improved in an iterative least squares optimization in the Lie algebra of SO (3) . In order to deal with outliers in the relative rotations, we developed a sequential graph optimization algorithm that is able to detect and eliminate incorrect rotations. From the beginning, we propagate covariance information which allows for a weighting in the least squares estimation. We evaluate our approach using both synthetic and real image datasets. Compared to recent state-of-the-art rotation averaging and global image orientation algorithms, our proposed scheme reaches a high degree of robustness and accuracy. Moreover, it is also applicable to large Internet datasets, which shows its efficiency.

  14. Effects of symbicort turbuhaler combined with tiotropium bromide on serum PCT, TIMP-1, MMP-9, IFN- γ , arterial blood gases and pulmonary function in patients with AECOPD

    Directory of Open Access Journals (Sweden)

    Yan Zhang

    2017-10-01

    Full Text Available Objective: To study the effects of symbicort turbuhaler combined with tiotropium bromide on serum PCT, TIMP-1, MMP-9, IFN-γ, arterial blood gases and pulmonary function in patients with AECOPD. Methods A total of 90 patients in our hospital with AECOPD during January 2014 to January 2017 were divided into the control group (n=45 and the treatment group (n=45 randomly. The control group was treated with tiotropium bromide; the treatment group was treated with symbicort turbuhaler combined with tiotropium bromide. The two groups were treated for 14 d. That was compared of the serum PCT, TIMP-1, MMP-9, IFN-γ, PaO 2 , SaO 2 , PaCO 2 , MPAP, PASP and PADP of the two groups before and after treatment. Results The serum PCT, TIMP-1, MMP-9, IFN-γ, PaO 2 , SaO 2 , PaCO 2 , MPAP, PASP and PADP of the two groups before treatment have no significantly differences. The serum PCT, TIMP-1, MMP-9 and IFN-γ levels of the two groups after treatment were significantly lower than before treatment. The serum PCT, TIMP-1, MMP-9 and IFN-γ levels of the treatment group after treatment were significantly lower than the control group. The PaO 2 , SaO 2 of the two groups after treatment were significantly higher than before treatment, the PaCO 2 , MPAP, PASP and PADP of the two groups after treatment were significantly lower than before treatment. The PaO 2 , SaO 2 , PaCO 2 , MPAP, PASP and PADP of the treatment group after treatment were significantly better than the control group. Conclusion Symbicort turbuhaler combined with tiotropium bromide can reduce the serum PCT, TIMP-1, MMP-9, IFN-γ levels and the pulmonary arterial hypertension, improve the lung tissue oxygen supply and the cardiopulmonary function, and it was worthy clinical application.

  15. Combining Different Modalities for 3D Imaging of Biological Objects

    CERN Document Server

    Tsyganov, E; Kulkarni, P; Mason, R; Parkey, R; Seliuonine, S; Shay, J; Soesbe, T; Zhezher, V; Zinchenko, A I

    2005-01-01

    A resolution enhanced NaI(Tl)-scintillator micro-SPECT device using pinhole collimator geometry has been built and tested with small animals. This device was constructed based on a depth-of-interaction measurement using a thick scintillator crystal and a position sensitive PMT to measure depth-dependent scintillator light profiles. Such a measurement eliminates the parallax error that degrades the high spatial resolution required for small animal imaging. This novel technique for 3D gamma-ray detection was incorporated into the micro-SPECT device and tested with a $^{57}$Co source and $^{98m}$Tc-MDP injected in mice body. To further enhance the investigating power of the tomographic imaging different imaging modalities can be combined. In particular, as proposed and shown in this paper, the optical imaging permits a 3D reconstruction of the animal's skin surface thus improving visualization and making possible depth-dependent corrections, necessary for bioluminescence 3D reconstruction in biological objects. ...

  16. Combining Constraint Types From Public Data in Aerial Image Segmentation

    DEFF Research Database (Denmark)

    Jacobsen, Thomas Stig; Jensen, Jacob Jon; Jensen, Daniel Rune

    2013-01-01

    detect the number of clusters using the elongated K-means algorithm instead of using the standard spectral clustering approach of a predefined number of clusters. The results are refined by filtering out noise with a binary morphological operator. Point data is used for semi-supervised labelling......We introduce a method for image segmentation that constraints the clustering with map and point data. The method is showcased by applying the spectral clustering algorithm on aerial images for building detection with constraints built from a height map and address point data. We automatically...... of building clusters. Our evaluation show that the combination of constraints have a positive impact on the clustering quality achieved. Finally we argue how the presented constraint types may be used in other applications....

  17. Shale gases

    International Nuclear Information System (INIS)

    Courme, Bruno

    2012-01-01

    This Power Point presentation comments the evolution of the World population, GDP and energy demand, the evolution of the nuclear mix by 2030, the oil and gas reserves. Then, the author defines the different hydrocarbon classes (conventional gas and oil, heavy oil, oil shale), describes how natural gas is trapped in low permeability rocks, the specific production techniques (horizontal drilling and hydraulic fracturing), and recalls the well architecture. Then, he more precisely presents the various aspects of hydraulic fracturing, outlines and comments the challenges raised by this technique regarding industry ability and means and water quality and consumption. He comments the geographical distribution of gas resources, and the share of shale gases, the impact on climate, and the European shale gas production potential

  18. Fuel gases

    International Nuclear Information System (INIS)

    Anon.

    1996-01-01

    This paper gives a brief presentation of the context, perspectives of production, specificities, and the conditions required for the development of NGV (Natural Gas for Vehicle) and LPG-f (Liquefied Petroleum Gas fuel) alternative fuels. After an historical presentation of 80 years of LPG evolution in vehicle fuels, a first part describes the economical and environmental advantages of gaseous alternative fuels (cleaner combustion, longer engines life, reduced noise pollution, greater natural gas reserves, lower political-economical petroleum dependence..). The second part gives a comparative cost and environmental evaluation between the available alternative fuels: bio-fuels, electric power and fuel gases, taking into account the processes and constraints involved in the production of these fuels. (J.S.)

  19. Meteosat third generation imager: simulation of the flexible combined imager instrument chain

    Science.gov (United States)

    Just, Dieter; Gutiérrez, Rebeca; Roveda, Fausto; Steenbergen, Theo

    2014-10-01

    The Meteosat Third Generation (MTG) Programme is the next generation of European geostationary meteorological systems. The first MTG satellite, MTG-I1, which is scheduled for launch at the end of 2018, will host two imaging instruments: the Flexible Combined Imager (FCI) and the Lightning Imager. The FCI will provide continuation of the SEVIRI imager operations on the current Meteosat Second Generation satellites (MSG), but with an improved spatial, temporal and spectral resolution, not dissimilar to GOES-R (of NASA/NOAA). Unlike SEVIRI on the spinning MSG spacecraft, the FCI will be mounted on a 3-axis stabilised platform and a 2-axis tapered scan will provide a full coverage of the Earth in 10 minute repeat cycles. Alternatively, a rapid scanning mode can cover smaller areas, but with a better temporal resolution of up to 2.5 minutes. In order to assess some of the data acquisition and processing aspects which will apply to the FCI, a simplified end-to-end imaging chain prototype was set up. The simulation prototype consists of four different functional blocks: - A function for the generation of FCI-like references images - An image acquisition simulation function for the FCI Line-of-Sight calculation and swath generation - A processing function that reverses the swath generation process by rectifying the swath data - An evaluation function for assessing the quality of the processed data with respect to the reference images This paper presents an overview of the FCI instrument chain prototype, covering instrument characteristics, reference image generation, image acquisition simulation, and processing aspects. In particular, it provides in detail the description of the generation of references images, highlighting innovative features, but also limitations. This is followed by a description of the image acquisition simulation process, and the rectification and evaluation function. The latter two are described in more detail in a separate paper. Finally, results

  20. Combining magnetic resonance imaging and ultrawideband radar: a new concept for multimodal biomedical imaging.

    Science.gov (United States)

    Thiel, F; Hein, M; Schwarz, U; Sachs, J; Seifert, F

    2009-01-01

    Due to the recent advances in ultrawideband (UWB) radar technologies, there has been widespread interest in the medical applications of this technology. We propose the multimodal combination of magnetic resonance (MR) and UWB radar for improved functional diagnosis and imaging. A demonstrator was established to prove the feasibility of the simultaneous acquisition of physiological events by magnetic resonance imaging and UWB radar. Furthermore, first in vivo experiments have been carried out, utilizing this new approach. Correlating the reconstructed UWB signals with physiological signatures acquired by simultaneous MR measurements, representing respiratory and myocardial displacements, gave encouraging results which can be improved by optimization of the MR data acquisition technique or the use of UWB antenna arrays to localize the motion in a focused area.

  1. Perceptual segmentation: combining image segmentation with object tagging.

    Science.gov (United States)

    Bergman, Ruth; Nachlieli, Hila

    2011-06-01

    Human observers understand the content of an image intuitively. Based upon image content, they perform many image-related tasks, such as creating slide shows and photo albums, and organizing their image archives. For example, to select photos for an album, people assess image quality based upon the main objects in the image. They modify colors in an image based upon the color of important objects, such as sky, grass or skin. Serious photographers might modify each object separately. Photo applications, in contrast, use low-level descriptors to guide similar tasks. Typical descriptors, such as color histograms, noise level, JPEG artifacts and overall sharpness, can guide an imaging application and safeguard against blunders. However, there is a gap between the outcome of such operations and the same task performed by a person. We believe that the gap can be bridged by automatically understanding the content of the image. This paper presents algorithms for automatic tagging of perceptual objects in images, including sky, skin, and foliage, which constitutes an important step toward this goal.

  2. The value of diffusion-weighted imaging in combination with T2-weighted imaging for rectal cancer detection

    International Nuclear Information System (INIS)

    Rao Shengxiang; Zeng Mengsu; Chen Caizhong; Li Renchen; Zhang Shujie; Xu Jianming; Hou Yingyong

    2008-01-01

    Objective: To evaluate the clinical value of diffusion-weighted imaging (DWI) in combination with T 2 -weighted imaging (T 2 WI) for the detection of rectal cancer as compared with T 2 WI alone. Materials and methods: Forty-five patients with rectal cancer and 20 without rectal cancer underwent DWI with parallel imaging and T 2 WI on a 1.5 T scanner. Images were independently reviewed by two readers blinded to the results to determine the detectability of rectal cancer. The detectability of T 2 W imaging without and with DW imaging was assessed by means of receiver operating characteristic analysis. The interobserver agreement between the two readers was calculated with kappa statistics. Results: The ROC analysis showed that each of two readers achieved more accurate results with T 2 W imaging combined with DW imaging than with T 2 W imaging alone significantly. The A z values for the two readers for each T 2 WI and T 2 WI combined with DWI were 0.918 versus 0.991 (p = 0.0494), 0.934 versus 0.997 (p = 0.0475), respectively. The values of kappa were 0.934 for T 2 WI and 0.948 for T 2 WI combined with DWI between the two readers. Conclusion: The addition of DW imaging to conventional T 2 W imaging provides better detection of rectal cancer

  3. Combined use of BP neural network and computational integral imaging reconstruction for optical multiple-image security

    Science.gov (United States)

    Li, Xiao Wei; Cho, Sung Jin; Kim, Seok Tae

    2014-03-01

    Integral imaging can provide a feasible and efficient technique for multiple-image encoding system. The computational integral imaging reconstruction (CIIR) technique reconstructs a set of plane images along the output plane, whereas the resolution of the reconstructed images will degrade due to the partial occlusion of other reconstructed images. Meanwhile, CIIR is a pixel-overlapping reconstruction method, in which the superimposition causes the undesirable interference. To overcome these problems, we first utilize the block matching algorithm to eliminate the occlusion-disturbance and introduce the back-propagation neural network algorithm to compensate for the low-resolution image. In the encryption, a computational integral imaging pickup technique is employed to record the multiple-image simultaneously to form an elemental image array (EIA). The EIA is then encrypted by combining the use of maximum length cellular automata (CA) and the double random phase encoding algorithm. Some numerical simulations have been made to demonstrate the performance of this encryption algorithm.

  4. A microscope for Fermi gases

    International Nuclear Information System (INIS)

    Omran, Ahmed

    2016-01-01

    This thesis reports on a novel quantum gas microscope to investigate many-body systems of fermionic atoms in optical lattices. Single-site resolved imaging of ultracold lattice gases has enabled powerful studies of bosonic quantum many-body systems. The extension of this capability to Fermi gases offers new prospects to studying complex phenomena of strongly correlated systems, for which numerical simulations are often out of reach. Using standard techniques of laser cooling, optical trapping, and evaporative cooling, ultracold Fermi gases of 6 Li are prepared and loaded into a large-scale 2D optical lattice of flexible geometry. The atomic distribution is frozen using a second, short-scaled lattice, where we perform Raman sideband cooling to induce fluorescence on each atom while maintaining its position. Together with high-resolution imaging, the fluorescence signals allow for reconstructing the initial atom distribution with single-site sensitivity and high fidelity. Magnetically driven evaporative cooling in the plane allows for producing degenerate Fermi gases with almost unity filling in the initial lattice, allowing for the first microscopic studies of ultracold gases with clear signatures of Fermi statistics. By preparing an ensemble of spin-polarised Fermi gases, we detect a flattening of the density profile towards the centre of the cloud, which is a characteristic of a band-insulating state. In one set of experiments, we demonstrate that losses of atom pairs on a single lattice site due to light-assisted collisions are circumvented. The oversampling of the second lattice allows for deterministic separation of the atom pairs into different sites. Compressing a high-density sample in a trap before loading into the lattice leads to many double occupancies of atoms populating different bands, which we can image with no evidence for pairwise losses. We therefore gain direct access to the true number statistics on each lattice site. Using this feature, we can

  5. Airborne Infrared and Visible Image Fusion Combined with Region Segmentation.

    Science.gov (United States)

    Zuo, Yujia; Liu, Jinghong; Bai, Guanbing; Wang, Xuan; Sun, Mingchao

    2017-05-15

    This paper proposes an infrared (IR) and visible image fusion method introducing region segmentation into the dual-tree complex wavelet transform (DTCWT) region. This method should effectively improve both the target indication and scene spectrum features of fusion images, and the target identification and tracking reliability of fusion system, on an airborne photoelectric platform. The method involves segmenting the region in an IR image by significance, and identifying the target region and the background region; then, fusing the low-frequency components in the DTCWT region according to the region segmentation result. For high-frequency components, the region weights need to be assigned by the information richness of region details to conduct fusion based on both weights and adaptive phases, and then introducing a shrinkage function to suppress noise; Finally, the fused low-frequency and high-frequency components are reconstructed to obtain the fusion image. The experimental results show that the proposed method can fully extract complementary information from the source images to obtain a fusion image with good target indication and rich information on scene details. They also give a fusion result superior to existing popular fusion methods, based on eithers subjective or objective evaluation. With good stability and high fusion accuracy, this method can meet the fusion requirements of IR-visible image fusion systems.

  6. Combined imaging and velocity estimation by Joint Migration Inversion

    NARCIS (Netherlands)

    Staal, X.R.

    2015-01-01

    Seismic imaging projects aim to reveal the structure of the earths crust from seismic data. These projects typically include three separate processing steps, being: • attenuation of multiple reflections in the seismic data. • estimating seismic wave propagation velocities from the seismic data. •

  7. Image combination enhancement method for X-ray compton back-scattering security inspection body scanner

    International Nuclear Information System (INIS)

    Wang Huaiying; Zhang Yujin; Yang Lirui; Li Dong

    2011-01-01

    As for X-ray Compton Back-Scattering (CBS) body scanner, image clearness is very important for the performance of detecting the contraband hidden on the body. A new image combination enhancement method is provided based on characteristics of CBS body images and points of human vision. After processed by this method, the CBS image will be obviously improved with clear levels, distinct outline and uniform background. (authors)

  8. Image quality and breast dose of 24 screen-film combinations for mammography.

    Science.gov (United States)

    Dimakopoulou, A D; Tsalafoutas, I A; Georgiou, E K; Yakoumakis, E N

    2006-02-01

    In this study the effect of different mammographic screen-film combinations on image quality and breast dose, and the correlation between the various image quality parameters, breast dose and the sensitometric parameters of a film were investigated. Three Agfa (MR5-II, HDR, HT), two Kodak (Min-R M, Min-R 2000), one Fuji (AD-M), one Konica (CM-H) and one Ferrania (HM plus) single emulsion mammographic films were combined with three intensifying screens (Agfa HDS, Kodak Min-R 2190 and Fuji AD-MA). The film characteristics were determined by sensitometry, while the image quality and the dose to the breast of the resulting 24 screen-film combinations were assessed using a mammography quality control phantom. For each combination, three images of the phantom were acquired with optical density within three different ranges. Two observers assessed the quality of the 72 phantom images obtained, while the breast dose was calculated from the exposure data required for each image. Large differences among screen-film combinations in terms of image quality and breast dose were identified however, that, could not be correlated with the film's sensitometric characteristics. All films presented the best resolution when combined with the HDS screen at the expense of speed, and the largest speed when combined with the AD-MA screen, without degradation of the overall image quality. However, an ideal screen-film combination presenting the best image quality with the least dose was not identified. It is also worth mentioning that the best performance for a film was not necessarily obtained when this was combined with the screen provided by the same manufacturer. The results of this study clearly demonstrate that comparison of films based on their sensitometric characteristics are of limited value for clinical practice, as their performance is strongly affected by the screens with which they are combined.

  9. Combined optical and single photon emission imaging: preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Boschi, Federico; Calderan, Laura; Sbarbati, Andrea [Department of Morphological-Biomedical Sciences, Section of Anatomy and Histology, University of Verona, Verona (Italy); Spinelli, Antonello E [Medical Physics Department, San Raffaele Scientific Institute, Milan (Italy); D' Ambrosio, Daniela; Marengo, Mario [Medical Physics Department, S. Orsola Malpighi Hospital, Bologna (Italy)], E-mail: federico.boschi@univr.it

    2009-12-07

    In vivo optical imaging instruments are generally devoted to the acquisition of light coming from fluorescence or bioluminescence processes. Recently, an instrument was conceived with radioisotopic detection capabilities (Kodak in Vivo Multispectral System F) based on the conversion of x-rays from the phosphorus screen. The goal of this work is to demonstrate that an optical imager (IVIS 200, Xenogen Corp., Alameda, USA), designed for in vivo acquisitions of small animals in bioluminescent and fluorescent modalities, can even be employed to detect signals due to radioactive tracers. Our system is based on scintillator crystals for the conversion of high-energy rays and a collimator. No hardware modifications are required. Crystals alone permit the acquisition of photons coming from an in vivo 20 g nude mouse injected with a solution of methyl diphosphonate technetium 99 metastable (Tc99m-MDP). With scintillator crystals and collimators, a set of measurements aimed to fully characterize the system resolution was carried out. More precisely, system point spread function and modulation transfer function were measured at different source depths. Results show that system resolution is always better than 1.3 mm when the source depth is less than 10 mm. The resolution of the images obtained with radioactive tracers is comparable with the resolution achievable with dedicated techniques. Moreover, it is possible to detect both optical and nuclear tracers or bi-modal tracers with only one instrument. (letter to the editor)

  10. Spoofing detection on facial images recognition using LBP and GLCM combination

    Science.gov (United States)

    Sthevanie, F.; Ramadhani, K. N.

    2018-03-01

    The challenge for the facial based security system is how to detect facial image falsification such as facial image spoofing. Spoofing occurs when someone try to pretend as a registered user to obtain illegal access and gain advantage from the protected system. This research implements facial image spoofing detection method by analyzing image texture. The proposed method for texture analysis combines the Local Binary Pattern (LBP) and Gray Level Co-occurrence Matrix (GLCM) method. The experimental results show that spoofing detection using LBP and GLCM combination achieves high detection rate compared to that of using only LBP feature or GLCM feature.

  11. Variable complementary combined radiologic imaging methods for breast diseases

    International Nuclear Information System (INIS)

    Oh, Ki Keun; Lee, Kyong Sik; Sohn, Seing Kook

    1985-01-01

    Radiographic examination of the breast has been so improved that it became a routine complement to physical examination. From November 1, 1983 through September 30, 1984, 684 patients with complains of various breast problem were examined by low-dose film mammography at Yong Dong Hospital, Yonsei University. Among them, a comparative studies, independently conducted physical examination, 97 cases of film mammography, 35 cases of ultrasound mammography, 16 cases of aspiration cytology, and 3 cases of galactography were performed for our pathologically proven 98 cases of breast diseases. Combined and complementary studies for breast diseases were analyzed in 37 proven cases and authors found that specificity of those combined immediate complementary study techniques for breast diseases were 94% under close cooperation with surgeon in Yong Dong Hospital, Yonsei University

  12. Combining stable isotope (δ13C) of trace gases and aerobiological data to monitor the entry and dispersion of microorganisms in caves.

    Science.gov (United States)

    Garcia-Anton, E; Cuezva, S; Jurado, V; Porca, E; Miller, A Z; Fernandez-Cortes, A; Saiz-Jimenez, C; Sanchez-Moral, S

    2014-01-01

    Altamira Cave (north of Spain) contains one of the world's most prominent Paleolithic rock art paintings, which are threatened by a massive microbial colonization of ceiling and walls. Previous studies revealed that exchange rates between the cave and the external atmosphere through the entrance door play a decisive role in the entry and transport of microorganisms (bacteria and fungi) and nutrients to the interior of the cave. A spatial-distributed sampling and measurement of carrier (CO2) and trace (CH4) gases and isotopic signal of CO2 (δ(13)C) inside the cave supports the existence of a second connection (active gas exchange processes) with the external atmosphere at or near the Well Hall, the innermost and deepest area of the cave. A parallel aerobiological study also showed that, in addition to the entrance door, there is another connection with the external atmosphere, which favors the transport and increases microorganism concentrations in the Well Hall. This double approach provides a more complete knowledge on cave ventilation and revealed the existence of unknown passageways in the cave, a fact that should be taken into account in future cave management.

  13. Marketing image categorization using hybrid human-machine combinations

    Science.gov (United States)

    Gnanasambandam, Nathan; Madhu, Himanshu

    2012-03-01

    Marketing instruments with nested, short-form, symbol loaded content need to be studied differently. Image classification in the Web2.0 world can dynamically use a configurable amount of internal and external data as well as varying levels of crowd-sourcing. Our work is one such examination of how to construct a hybrid technique involving learning and crowd-sourcing. Through a parameter called turkmix and a multitude of crowd-sourcing techniques available we show that we can control the trend of metrics such as precision and recall on the hybrid categorizer.

  14. Handbook of purified gases

    CERN Document Server

    Schoen, Helmut

    2015-01-01

    Technical gases are used in almost every field of industry, science and medicine and also as a means of control by government authorities and institutions and are regarded as indispensable means of assistance. In this complete handbook of purified gases the physical foundations of purified gases and mixtures as well as their manufacturing, purification, analysis, storage, handling and transport are presented in a comprehensive way. This important reference work is accompanied with a large number of Data Sheets dedicated to the most important purified gases.  

  15. Gases in molten salts

    CERN Document Server

    Tomkins, RPT

    1991-01-01

    This volume contains tabulated collections and critical evaluations of original data for the solubility of gases in molten salts, gathered from chemical literature through to the end of 1989. Within the volume, material is arranged according to the individual gas. The gases include hydrogen halides, inert gases, oxygen, nitrogen, hydrogen, carbon dioxide, water vapor and halogens. The molten salts consist of single salts, binary mixtures and multicomponent systems. Included also, is a special section on the solubility of gases in molten silicate systems, focussing on slags and fluxes.

  16. Combination tomographic and cardiographic ultrasonic imaging method and system

    International Nuclear Information System (INIS)

    Yano, T.; Fukukita, H.; Fukumoto, A.; Hayakawa, Y.; Irioka, K.

    1984-01-01

    Ultrasonic echo signals are successively sampled and converted to digital echo data which are written into a first digital memory column by column and then read out row by row into a first buffer memory. The digital echo data which are derived in response to beams successively transmitted in a predetermined direction are written into columns of a second digital memory and read out of the memory in rows into a second buffer memory. The data stored in the first and second buffer memories are read out for digital-to-analog conversion and selectively applied within a television ''frame'' interval to control electron beam intensity of a single cathode ray tube so as to present tomographic and cardiographic images in different display areas of the tube

  17. Change Detection in Uav Video Mosaics Combining a Feature Based Approach and Extended Image Differencing

    Science.gov (United States)

    Saur, Günter; Krüger, Wolfgang

    2016-06-01

    Change detection is an important task when using unmanned aerial vehicles (UAV) for video surveillance. We address changes of short time scale using observations in time distances of a few hours. Each observation (previous and current) is a short video sequence acquired by UAV in near-Nadir view. Relevant changes are, e.g., recently parked or moved vehicles. Examples for non-relevant changes are parallaxes caused by 3D structures of the scene, shadow and illumination changes, and compression or transmission artifacts. In this paper we present (1) a new feature based approach to change detection, (2) a combination with extended image differencing (Saur et al., 2014), and (3) the application to video sequences using temporal filtering. In the feature based approach, information about local image features, e.g., corners, is extracted in both images. The label "new object" is generated at image points, where features occur in the current image and no or weaker features are present in the previous image. The label "vanished object" corresponds to missing or weaker features in the current image and present features in the previous image. This leads to two "directed" change masks and differs from image differencing where only one "undirected" change mask is extracted which combines both label types to the single label "changed object". The combination of both algorithms is performed by merging the change masks of both approaches. A color mask showing the different contributions is used for visual inspection by a human image interpreter.

  18. Characterization of human carotid atherosclerotic tissues imaged by combining multiple multiphoton microscopy techniques

    Science.gov (United States)

    Baria, E.; Cicchi, R.; Nesi, G.; Massi, D.; Pavone, F. S.

    2017-07-01

    We combined Second Harmonic Generation, Two-Photon Fluorescence and Fluorescence Lifetime Imaging Microscopy for studying human carotid ex vivo tissue sections affected by atherosclerosis, resulting in the discrimination of different arterial regions within the plaques.

  19. Biomedical imaging modality classification using combined visual features and textual terms.

    Science.gov (United States)

    Han, Xian-Hua; Chen, Yen-Wei

    2011-01-01

    We describe an approach for the automatic modality classification in medical image retrieval task of the 2010 CLEF cross-language image retrieval campaign (ImageCLEF). This paper is focused on the process of feature extraction from medical images and fuses the different extracted visual features and textual feature for modality classification. To extract visual features from the images, we used histogram descriptor of edge, gray, or color intensity and block-based variation as global features and SIFT histogram as local feature. For textual feature of image representation, the binary histogram of some predefined vocabulary words from image captions is used. Then, we combine the different features using normalized kernel functions for SVM classification. Furthermore, for some easy misclassified modality pairs such as CT and MR or PET and NM modalities, a local classifier is used for distinguishing samples in the pair modality to improve performance. The proposed strategy is evaluated with the provided modality dataset by ImageCLEF 2010.

  20. Combination of Spatial Domain Filters for Speckle Noise Reduction in Ultrasound Medical Images

    Directory of Open Access Journals (Sweden)

    Amit Garg

    2017-01-01

    Full Text Available The occurrence of speckle noise in medical Ultrasound (US images poses a big challenge to medical practitioners over last several years. Speckle noise reduces the fine details present in the images and hence make it more difficult to diagnose. In this paper, a~novel method based on the combination of three spatial domain filters is presented. The output of these filters is combined on the basis of an Intensity Classifier Map (ICF formed using Coefficient of Dispersion (CoD parameter. Experiments were conducted on synthetic and real US images. Quantitative and qualitative analysis of the proposed method is carried out in comparison to other six existing methods. It has been found from the obtained results that proposed method delivers observable improvement in all quantitative parameters undertaken for synthetic US image and in MVR value for real US images. Also, the effectiveness of the proposed method is found to be consistent with qualitative assessment of the denoised images.

  1. Infrared (IR) remote sensing of gases

    OpenAIRE

    López Martínez, Fernando

    2008-01-01

    The IR Imaging and Remote Sensing Laboratory – LIR-UC3M of Universidad Carlos III, has developed Multi and Hyper spectral Infrared (IR) analysis techniques for gas remote sensing. Design of specific sensors for the determination of gases and their concentration are proposed. Almost all gases (CO2, CO, NO2, O3, HC o NH, …) related to industrial, environmental or military safety can be detected. Companies or centres with interest in the use of specific application sensors are required.

  2. Ultrasmall Biocompatible WO3- x Nanodots for Multi-Modality Imaging and Combined Therapy of Cancers.

    Science.gov (United States)

    Wen, Ling; Chen, Ling; Zheng, Shimin; Zeng, Jianfeng; Duan, Guangxin; Wang, Yong; Wang, Guanglin; Chai, Zhifang; Li, Zhen; Gao, Mingyuan

    2016-07-01

    Ultrasmall biocompatible WO3 - x nanodots with an outstanding X-ray radiation sensitization effect are prepared, and demonstrated to be applicable for multi-modality tumor imaging through computed tomography and photoacoustic imaging (PAI), and effective cancer treatment combining both photothermal therapy and radiation therapy. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Combined multi-kernel head computed tomography images optimized for depicting both brain parenchyma and bone.

    Science.gov (United States)

    Takagi, Satoshi; Nagase, Hiroyuki; Hayashi, Tatsuya; Kita, Tamotsu; Hayashi, Katsumi; Sanada, Shigeru; Koike, Masayuki

    2014-01-01

    The hybrid convolution kernel technique for computed tomography (CT) is known to enable the depiction of an image set using different window settings. Our purpose was to decrease the number of artifacts in the hybrid convolution kernel technique for head CT and to determine whether our improved combined multi-kernel head CT images enabled diagnosis as a substitute for both brain (low-pass kernel-reconstructed) and bone (high-pass kernel-reconstructed) images. Forty-four patients with nondisplaced skull fractures were included. Our improved multi-kernel images were generated so that pixels of >100 Hounsfield unit in both brain and bone images were composed of CT values of bone images and other pixels were composed of CT values of brain images. Three radiologists compared the improved multi-kernel images with bone images. The improved multi-kernel images and brain images were identically displayed on the brain window settings. All three radiologists agreed that the improved multi-kernel images on the bone window settings were sufficient for diagnosing skull fractures in all patients. This improved multi-kernel technique has a simple algorithm and is practical for clinical use. Thus, simplified head CT examinations and fewer images that need to be stored can be expected.

  4. Combined optimization of image-gathering optics and image-processing algorithm for edge detection

    Science.gov (United States)

    Halyo, N.; Samms, R. W.

    1986-01-01

    This paper investigates the relationships between the image-gathering and image-processing systems for minimum mean-squared error estimation of scene characteristics. A stochastic optimization problem is formulated in which the objective is to determine a spatial characteristic of the scene rather than a feature of the already blurred, sampled, and noisy image data. The Wiener filter for the sampled image case is obtained as a special case, where the desired characteristics is scene restoration. Optimal edge detection is investigated. It is shown that the optimal edge detector compensates for the blurring introduced by the image-gathering optics, and, notably, that it is not circularly symmetric. The lack of circular symmetry is largely due to the geometric effects of the sampling lattice used in image acquisition.

  5. Combination of broadband diffuse optical spectroscopy with magnetic resonance imaging

    Science.gov (United States)

    Merritt, Sean Isaiah

    Broadband diffuse optical spectroscopy (DOS) is an emerging optical technique used to measure absorption and scattering of bulk tissue non-invasively within the near-infrared (600--1050 nm). The ultimate aim of my advisors group is for broadband DOS to become an established medical diagnostic technique used clinically on various tissue types including breast, muscle and bone. The specific goal for my research is to use established magnetic resonance (MR) techniques for the purpose of continued development and validation of broadband DOS. The initial studies carried out were a validation of broadband DOS through a direct comparison with MRI. Both techniques are sensitive to signals produced by water and lipids in tissue. There is also sensitivity to blood flow, which MRI measures using exogenous contrast agents and broadband DOS is sensitive through measurement of total hemoglobin content (THC) and tissue oxygen saturation (StO2). These validation studies were compared initially in a rat tumor model in which both techniques were used simultaneously. A qualitative correlation was found between the MR images of water content and blood perfusion compared with the DOS water and THC values. A more quantitative comparison was made between measuring absolute water and lipid content in phantoms and in human tissue, which showed a strong correlation. The in vivo study also validated that broadband DOS was interrogating bone marrow in the tibia. The second half of this thesis is focused on developing new capabilities of broadband DOS and the MRI literature is used as a guide. When a water molecule hydrogen bonds to another molecule, the absorption spectrum in the near-infrared which is due to the vibrational overtone of the OH bond will change. The expected changes were observed in tissue and an algorithm was developed to fit for a tissue bound water parameter. Also, as tissue temperature changes, the fraction of water bound to other water molecules changes and can be used to

  6. Combination strategies in multi-atlas image segmentation: application to brain MR data.

    Science.gov (United States)

    Artaechevarria, Xabier; Munoz-Barrutia, Arrate; Ortiz-de-Solorzano, Carlos

    2009-08-01

    It has been shown that employing multiple atlas images improves segmentation accuracy in atlas-based medical image segmentation. Each atlas image is registered to the target image independently and the calculated transformation is applied to the segmentation of the atlas image to obtain a segmented version of the target image. Several independent candidate segmentations result from the process, which must be somehow combined into a single final segmentation. Majority voting is the generally used rule to fuse the segmentations, but more sophisticated methods have also been proposed. In this paper, we show that the use of global weights to ponderate candidate segmentations has a major limitation. As a means to improve segmentation accuracy, we propose the generalized local weighting voting method. Namely, the fusion weights adapt voxel-by-voxel according to a local estimation of segmentation performance. Using digital phantoms and MR images of the human brain, we demonstrate that the performance of each combination technique depends on the gray level contrast characteristics of the segmented region, and that no fusion method yields better results than the others for all the regions. In particular, we show that local combination strategies outperform global methods in segmenting high-contrast structures, while global techniques are less sensitive to noise when contrast between neighboring structures is low. We conclude that, in order to achieve the highest overall segmentation accuracy, the best combination method for each particular structure must be selected.

  7. 3D UWB Magnitude-Combined Tomographic Imaging for Biomedical Applications. Algorithm Validation

    Directory of Open Access Journals (Sweden)

    S. Capdevila

    2011-06-01

    Full Text Available Biomedical microwave imaging is a topic of continuous research for its potential in different areas especially in breast cancer detection. In this paper, 3D UWB Magnitude-Combined tomographic algorithm is assessed for this recurrent application, but also for a more challenging one such as brain stroke detection. With the UWB Magnitude-Combined concept, the algorithm can take advantage of both the efficiency of Fourier Diffraction Theorem-based tomographic formulation and the robustness and image quality improvement provided by a multi-frequency combination.

  8. Combined optimization of image-gathering and image-processing systems for scene feature detection

    Science.gov (United States)

    Halyo, Nesim; Arduini, Robert F.; Samms, Richard W.

    1987-01-01

    The relationship between the image gathering and image processing systems for minimum mean squared error estimation of scene characteristics is investigated. A stochastic optimization problem is formulated where the objective is to determine a spatial characteristic of the scene rather than a feature of the already blurred, sampled and noisy image data. An analytical solution for the optimal characteristic image processor is developed. The Wiener filter for the sampled image case is obtained as a special case, where the desired characteristic is scene restoration. Optimal edge detection is investigated using the Laplacian operator x G as the desired characteristic, where G is a two dimensional Gaussian distribution function. It is shown that the optimal edge detector compensates for the blurring introduced by the image gathering optics, and notably, that it is not circularly symmetric. The lack of circular symmetry is largely due to the geometric effects of the sampling lattice used in image acquisition. The optimal image gathering optical transfer function is also investigated and the results of a sensitivity analysis are shown.

  9. Image-Based Airborne Sensors: A Combined Approach for Spectral Signatures Classification through Deterministic Simulated Annealing

    Science.gov (United States)

    Guijarro, María; Pajares, Gonzalo; Herrera, P. Javier

    2009-01-01

    The increasing technology of high-resolution image airborne sensors, including those on board Unmanned Aerial Vehicles, demands automatic solutions for processing, either on-line or off-line, the huge amountds of image data sensed during the flights. The classification of natural spectral signatures in images is one potential application. The actual tendency in classification is oriented towards the combination of simple classifiers. In this paper we propose a combined strategy based on the Deterministic Simulated Annealing (DSA) framework. The simple classifiers used are the well tested supervised parametric Bayesian estimator and the Fuzzy Clustering. The DSA is an optimization approach, which minimizes an energy function. The main contribution of DSA is its ability to avoid local minima during the optimization process thanks to the annealing scheme. It outperforms simple classifiers used for the combination and some combined strategies, including a scheme based on the fuzzy cognitive maps and an optimization approach based on the Hopfield neural network paradigm. PMID:22399989

  10. Storm diagnostic/predictive images derived from a combination of lightning and satellite imagery

    Science.gov (United States)

    Goodman, Steven J.; Buechler, Dennis E.; Meyer, Paul J.

    1988-01-01

    A technique is presented for generating trend or convective tendency images using a combination of GOES satellite imagery and cloud-to-ground lightning observations. The convective tendency images can be used for short term forecasting of storm development. A conceptual model of cloud electrical development and an example of the methodology used to generate lightning/satellite convective tendency imagery are given. Successive convective tendency images can be looped or animated to show the previous growth or decay of thunderstorms and their associated lighting activity. It is suggested that the convective tendency image may also be used to indicate potential microburst producing storms.

  11. In vivo tumor detection with combined MR–Photoacoustic-Thermoacoustic imaging

    Directory of Open Access Journals (Sweden)

    Lin Huang

    2016-09-01

    Full Text Available Here, we report a new method using combined magnetic resonance (MR–Photoacoustic (PA–Thermoacoustic (TA imaging techniques, and demonstrate its unique ability for in vivo cancer detection using tumor-bearing mice. Circular scanning TA and PA imaging systems were used to recover the dielectric and optical property distributions of three colon carcinoma bearing mice While a 7.0-T magnetic resonance imaging (MRI unit with a mouse body volume coil was utilized for high resolution structural imaging of the same mice. Three plastic tubes filled with soybean sauce were used as fiducial markers for the co-registration of MR, PA and TA images. The resulting fused images provided both enhanced tumor margin and contrast relative to the surrounding normal tissues. In particular, some finger-like protrusions extending into the surrounding tissues were revealed in the MR/TA infused images. These results show that the tissue functional optical and dielectric properties provided by PA and TA images along with the anatomical structure by MRI in one picture make accurate tumor identification easier. This combined MR–PA–TA-imaging strategy has the potential to offer a clinically useful triple-modality tool for accurate cancer detection and for intraoperative surgical navigation.

  12. Preoperative detection of hepatocellular carcinoma: comparison of combined constrast-enhanced MR imaging and combined CT during arterial portography and CT hepatic arteriography

    International Nuclear Information System (INIS)

    Kwak, H.S.; Kim, C.S.; Lee, J.M.; Seoul National University Medical Research Center

    2004-01-01

    The aim of this study was to compare Gd-DTPA-enhanced dynamic MR images, superparamagnetic iron oxide (SPIO)-enhanced MR images, combined Gd-DTPA-enhanced dynamic and SPIO-enhanced MR images, vs combined CT arterial portography (CTAP) and CT hepatic arteriography (CTHA), in the detection of hepatocellular carcinoma (HCC) using receiver operating characteristic (ROC) analysis. Twenty-four patients with 38 nodular HCCs (5-60 mm, mean 23.0 mm) were retrospectively analyzed. Image reviews were conducted on a liver segment-by-segment basis. A total of 192 segments, including 36 segments with 38 HCC, were reviewed independently by three radiologists. Each radiologist read four sets of images (set 1, unenhanced and Gd-DTPA-enhanced dynamic MR images; set 2, unenhanced and SPIO-enhanced MR images; set 3, combined Gd-DTPA-enhanced dynamic and SPIO-enhanced MR images; set 4, combined CTAP and CTHA). To minimize any possible learning bias, the reviewing order was randomized and the reviewing procedure was performed in four sessions at 2-week intervals. The diagnostic accuracy (Az values) for HCCs of combined CTAP and CTHA, combined Gd-DTPA-enhanced dynamic and SPIO-enhanced MR images, Gd-DTPA-enhanced dynamic MR images, and SPIO-enhanced MR images for all observers were 0.934, 0.963, 0.878, and 0.869, respectively. The diagnostic accuracy of combined CTAP and CTHA and combined Gd-DTPA-enhanced dynamic and SPIO-enhanced MR images was significantly higher than Gd-DTPA-enhanced dynamic MR images or SPIO-enhanced MR images (p<0.005). The mean specificity of combined CTAP and CTHA (93%) and combined Gd-DTPA-enhanced dynamic and SPIO-enhanced MR images (95%) was significantly higher than Gd-DTPA-enhanced dynamic MR images (87%) or SPIO-enhanced MR images (88%; p<0.05). Combined Gd-DTPA-enhanced dynamic and SPIO-enhanced MR images may obviate the need for more invasive combined CTAP and CTHA for the preoperative evaluation of patients with HCC

  13. Radar correlated imaging for extended target by the combination of negative exponential restraint and total variation

    Science.gov (United States)

    Qian, Tingting; Wang, Lianlian; Lu, Guanghua

    2017-07-01

    Radar correlated imaging (RCI) introduces the optical correlated imaging technology to traditional microwave imaging, which has raised widespread concern recently. Conventional RCI methods neglect the structural information of complex extended target, which makes the quality of recovery result not really perfect, thus a novel combination of negative exponential restraint and total variation (NER-TV) algorithm for extended target imaging is proposed in this paper. The sparsity is measured by a sequential order one negative exponential function, then the 2D total variation technique is introduced to design a novel optimization problem for extended target imaging. And the proven alternating direction method of multipliers is applied to solve the new problem. Experimental results show that the proposed algorithm could realize high resolution imaging efficiently for extended target.

  14. Improved contrast for high frame rate imaging using coherent compounding combined with spatial matched filtering.

    Science.gov (United States)

    Lou, Yang; Yen, Jesse T

    2017-07-01

    The concept of high frame rate ultrasound imaging (typically greater than 1000 frames per second) has inspired new fields of clinical applications for ultrasound imaging such as fast cardiovascular imaging, fast Doppler imaging and real-time 3D imaging. Coherent plane-wave compounding is a promising beamforming technique to achieve high frame rate imaging. By combining echoes from plane waves with different angles, dynamic transmit focusing is efficiently accomplished at all points in the image field. Meanwhile, the image frame rate can still be kept at a high level. Spatial matched filtering (SMF) with plane-wave insonification is a novel ultrafast beamforming method. An analytical study shows that SMF is equivalent to synthetic aperture methods that can provide dynamic transmit-receive focusing throughout the field of view. Experimental results show that plane-wave SMF has better performance than dynamic-receive focusing. In this paper, we propose integrating coherent plane-wave compounding with SMF to obtain greater image contrast. By using a combination of SMF beamformed images, image contrast is improved without degrading its high frame rate capabilities. The performance of compounded SMF (CSMF) is evaluated and compared with that of synthetic aperture focusing technique (SAFT) beamforming and compounded dynamic-receive-focus (CDRF) beamforming. The image quality of different beamforming methods was quantified in terms of contrast-to-noise ratio (CNR). Our results show that the new SMF based plane-wave compounding method provides better contrast than DAS based compounding method. Also CSMF can obtain a similar contrast level to dynamic transmit-receive focusing with only 21 transmit events. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Kinetic theory of gases

    CERN Document Server

    Kauzmann, Walter

    2012-01-01

    Monograph and text supplement for first-year students of physical chemistry focuses chiefly on the molecular basis of important thermodynamic properties of gases, including pressure, temperature, and thermal energy. 1966 edition.

  16. Gases in groundwater

    International Nuclear Information System (INIS)

    Vogel, J.C.; Heaton, T.H.E.

    1979-01-01

    Contributing to both economic and environmental spheres, radon and helium contained in groundwater are being used to detect uranium mineralisation and in conjunction with other gases, to locate natural gas and oil deposits; they are also helping to unravel the earth's past climatic history. Analysis of the gases dissolved in groundwater is proving useful in widely different fields ranging from uranium exploration, to earthquake prediction and the determination of palaeotemperatures [af

  17. Classification of MR brain images by combination of multi-CNNs for AD diagnosis

    Science.gov (United States)

    Cheng, Danni; Liu, Manhua; Fu, Jianliang; Wang, Yaping

    2017-07-01

    Alzheimer's disease (AD) is an irreversible neurodegenerative disorder with progressive impairment of memory and cognitive functions. Its early diagnosis is crucial for development of future treatment. Magnetic resonance images (MRI) play important role to help understand the brain anatomical changes related to AD. Conventional methods extract the hand-crafted features such as gray matter volumes and cortical thickness and train a classifier to distinguish AD from other groups. Different from these methods, this paper proposes to construct multiple deep 3D convolutional neural networks (3D-CNNs) to learn the various features from local brain images which are combined to make the final classification for AD diagnosis. First, a number of local image patches are extracted from the whole brain image and a 3D-CNN is built upon each local patch to transform the local image into more compact high-level features. Then, the upper convolution and fully connected layers are fine-tuned to combine the multiple 3D-CNNs for image classification. The proposed method can automatically learn the generic features from imaging data for classification. Our method is evaluated using T1-weighted structural MR brain images on 428 subjects including 199 AD patients and 229 normal controls (NC) from Alzheimer's Disease Neuroimaging Initiative (ADNI) database. Experimental results show that the proposed method achieves an accuracy of 87.15% and an AUC (area under the ROC curve) of 92.26% for AD classification, demonstrating the promising classification performances.

  18. A combined use of multispectral and SAR images for ship detection and characterization through object based image analysis

    Science.gov (United States)

    Aiello, Martina; Gianinetto, Marco

    2017-10-01

    Marine routes represent a huge portion of commercial and human trades, therefore surveillance, security and environmental protection themes are gaining increasing importance. Being able to overcome the limits imposed by terrestrial means of monitoring, ship detection from satellite has recently prompted a renewed interest for a continuous monitoring of illegal activities. This paper describes an automatic Object Based Image Analysis (OBIA) approach to detect vessels made of different materials in various sea environments. The combined use of multispectral and SAR images allows for a regular observation unrestricted by lighting and atmospheric conditions and complementarity in terms of geographic coverage and geometric detail. The method developed adopts a region growing algorithm to segment the image in homogeneous objects, which are then classified through a decision tree algorithm based on spectral and geometrical properties. Then, a spatial analysis retrieves the vessels' position, length and heading parameters and a speed range is associated. Optimization of the image processing chain is performed by selecting image tiles through a statistical index. Vessel candidates are detected over amplitude SAR images using an adaptive threshold Constant False Alarm Rate (CFAR) algorithm prior the object based analysis. Validation is carried out by comparing the retrieved parameters with the information provided by the Automatic Identification System (AIS), when available, or with manual measurement when AIS data are not available. The estimation of length shows R2=0.85 and estimation of heading R2=0.92, computed as the average of R2 values obtained for both optical and radar images.

  19. Combining textual and visual information for image retrieval in the medical domain.

    Science.gov (United States)

    Gkoufas, Yiannis; Morou, Anna; Kalamboukis, Theodore

    2011-01-01

    In this article we have assembled the experience obtained from our participation in the imageCLEF evaluation task over the past two years. Exploitation on the use of linear combinations for image retrieval has been attempted by combining visual and textual sources of images. From our experiments we conclude that a mixed retrieval technique that applies both textual and visual retrieval in an interchangeably repeated manner improves the performance while overcoming the scalability limitations of visual retrieval. In particular, the mean average precision (MAP) has increased from 0.01 to 0.15 and 0.087 for 2009 and 2010 data, respectively, when content-based image retrieval (CBIR) is performed on the top 1000 results from textual retrieval based on natural language processing (NLP).

  20. Combined image-processing algorithms for improved optical coherence tomography of prostate nerves

    Science.gov (United States)

    Chitchian, Shahab; Weldon, Thomas P.; Fiddy, Michael A.; Fried, Nathaniel M.

    2010-07-01

    Cavernous nerves course along the surface of the prostate gland and are responsible for erectile function. These nerves are at risk of injury during surgical removal of a cancerous prostate gland. In this work, a combination of segmentation, denoising, and edge detection algorithms are applied to time-domain optical coherence tomography (OCT) images of rat prostate to improve identification of cavernous nerves. First, OCT images of the prostate are segmented to differentiate the cavernous nerves from the prostate gland. Then, a locally adaptive denoising algorithm using a dual-tree complex wavelet transform is applied to reduce speckle noise. Finally, edge detection is used to provide deeper imaging of the prostate gland. Combined application of these three algorithms results in improved signal-to-noise ratio, imaging depth, and automatic identification of the cavernous nerves, which may be of direct benefit for use in laparoscopic and robotic nerve-sparing prostate cancer surgery.

  1. A modified approach combining FNEA and watershed algorithms for segmenting remotely-sensed optical images

    Science.gov (United States)

    Liu, Likun

    2018-01-01

    In the field of remote sensing image processing, remote sensing image segmentation is a preliminary step for later analysis of remote sensing image processing and semi-auto human interpretation, fully-automatic machine recognition and learning. Since 2000, a technique of object-oriented remote sensing image processing method and its basic thought prevails. The core of the approach is Fractal Net Evolution Approach (FNEA) multi-scale segmentation algorithm. The paper is intent on the research and improvement of the algorithm, which analyzes present segmentation algorithms and selects optimum watershed algorithm as an initialization. Meanwhile, the algorithm is modified by modifying an area parameter, and then combining area parameter with a heterogeneous parameter further. After that, several experiments is carried on to prove the modified FNEA algorithm, compared with traditional pixel-based method (FCM algorithm based on neighborhood information) and combination of FNEA and watershed, has a better segmentation result.

  2. Transferability and accuracy by combining dispersionless density functional and incremental post-Hartree-Fock theories: Noble gases adsorption on coronene/graphene/graphite surfaces

    International Nuclear Information System (INIS)

    Lara-Castells, María Pilar de; Bartolomei, Massimiliano; Mitrushchenkov, Alexander O.; Stoll, Hermann

    2015-01-01

    The accuracy and transferability of the electronic structure approach combining dispersionless density functional theory (DFT) [K. Pernal et al., Phys. Rev. Lett. 103, 263201 (2009)] with the method of increments [H. Stoll, J. Chem. Phys. 97, 8449 (1992)], are validated for the interaction between the noble-gas Ne, Ar, Kr, and Xe atoms and coronene/graphene/graphite surfaces. This approach uses the method of increments for surface cluster models to extract intermonomer dispersion-like (2- and 3-body) correlation terms at coupled cluster singles and doubles and perturbative triples level, while periodic dispersionless density functionals calculations are performed to estimate the sum of Hartree-Fock and intramonomer correlation contributions. Dispersion energy contributions are also obtained using DFT-based symmetry-adapted perturbation theory [SAPT(DFT)]. An analysis of the structure of the X/surface (X = Ne, Ar, Kr, and Xe) interaction energies shows the excellent transferability properties of the leading intermonomer correlation contributions across the sequence of noble-gas atoms, which are also discussed using the Drude oscillator model. We further compare these results with van der Waals-(vdW)-corrected DFT-based approaches. As a test of accuracy, the energies of the low-lying nuclear bound states supported by the laterally averaged X/graphite potentials (X = 3 He, 4 He, Ne, Ar, Kr, and Xe) are calculated and compared with the best estimations from experimental measurements and an atom-bond potential model using the ab initio-assisted fine-tuning of semiempirical parameters. The bound-state energies determined differ by less than 6–7 meV (6%) from the atom-bond potential model. The crucial importance of including incremental 3-body dispersion-type terms is clearly demonstrated, showing that the SAPT(DFT) approach effectively account for these terms. With the deviations from the best experimental-based estimations smaller than 2.3 meV (1.9%), the accuracy of

  3. Transferability and accuracy by combining dispersionless density functional and incremental post-Hartree-Fock theories: Noble gases adsorption on coronene/graphene/graphite surfaces.

    Science.gov (United States)

    de Lara-Castells, María Pilar; Bartolomei, Massimiliano; Mitrushchenkov, Alexander O; Stoll, Hermann

    2015-11-21

    The accuracy and transferability of the electronic structure approach combining dispersionless density functional theory (DFT) [K. Pernal et al., Phys. Rev. Lett. 103, 263201 (2009)] with the method of increments [H. Stoll, J. Chem. Phys. 97, 8449 (1992)], are validated for the interaction between the noble-gas Ne, Ar, Kr, and Xe atoms and coronene/graphene/graphite surfaces. This approach uses the method of increments for surface cluster models to extract intermonomer dispersion-like (2- and 3-body) correlation terms at coupled cluster singles and doubles and perturbative triples level, while periodic dispersionless density functionals calculations are performed to estimate the sum of Hartree-Fock and intramonomer correlation contributions. Dispersion energy contributions are also obtained using DFT-based symmetry-adapted perturbation theory [SAPT(DFT)]. An analysis of the structure of the X/surface (X = Ne, Ar, Kr, and Xe) interaction energies shows the excellent transferability properties of the leading intermonomer correlation contributions across the sequence of noble-gas atoms, which are also discussed using the Drude oscillator model. We further compare these results with van der Waals-(vdW)-corrected DFT-based approaches. As a test of accuracy, the energies of the low-lying nuclear bound states supported by the laterally averaged X/graphite potentials (X = (3)He, (4)He, Ne, Ar, Kr, and Xe) are calculated and compared with the best estimations from experimental measurements and an atom-bond potential model using the ab initio-assisted fine-tuning of semiempirical parameters. The bound-state energies determined differ by less than 6-7 meV (6%) from the atom-bond potential model. The crucial importance of including incremental 3-body dispersion-type terms is clearly demonstrated, showing that the SAPT(DFT) approach effectively account for these terms. With the deviations from the best experimental-based estimations smaller than 2.3 meV (1.9%), the accuracy of

  4. Transferability and accuracy by combining dispersionless density functional and incremental post-Hartree-Fock theories: Noble gases adsorption on coronene/graphene/graphite surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Lara-Castells, María Pilar de, E-mail: Pilar.deLara.Castells@csic.es; Bartolomei, Massimiliano [Instituto de Física Fundamental (C.S.I.C.), Serrano 123, E-28006 Madrid (Spain); Mitrushchenkov, Alexander O. [Laboratoire Modélisation et Simulation Multi Echelle, Université Paris-Est, MSME UMR 8208 CNRS, 5 bd Descartes, 77454 Marne-la-Vallée (France); Stoll, Hermann [Institut für Theoretische Chemie, Universität Stuttgart, D-70550 Stuttgart (Germany)

    2015-11-21

    The accuracy and transferability of the electronic structure approach combining dispersionless density functional theory (DFT) [K. Pernal et al., Phys. Rev. Lett. 103, 263201 (2009)] with the method of increments [H. Stoll, J. Chem. Phys. 97, 8449 (1992)], are validated for the interaction between the noble-gas Ne, Ar, Kr, and Xe atoms and coronene/graphene/graphite surfaces. This approach uses the method of increments for surface cluster models to extract intermonomer dispersion-like (2- and 3-body) correlation terms at coupled cluster singles and doubles and perturbative triples level, while periodic dispersionless density functionals calculations are performed to estimate the sum of Hartree-Fock and intramonomer correlation contributions. Dispersion energy contributions are also obtained using DFT-based symmetry-adapted perturbation theory [SAPT(DFT)]. An analysis of the structure of the X/surface (X = Ne, Ar, Kr, and Xe) interaction energies shows the excellent transferability properties of the leading intermonomer correlation contributions across the sequence of noble-gas atoms, which are also discussed using the Drude oscillator model. We further compare these results with van der Waals-(vdW)-corrected DFT-based approaches. As a test of accuracy, the energies of the low-lying nuclear bound states supported by the laterally averaged X/graphite potentials (X = {sup 3}He, {sup 4}He, Ne, Ar, Kr, and Xe) are calculated and compared with the best estimations from experimental measurements and an atom-bond potential model using the ab initio-assisted fine-tuning of semiempirical parameters. The bound-state energies determined differ by less than 6–7 meV (6%) from the atom-bond potential model. The crucial importance of including incremental 3-body dispersion-type terms is clearly demonstrated, showing that the SAPT(DFT) approach effectively account for these terms. With the deviations from the best experimental-based estimations smaller than 2.3 meV (1.9%), the

  5. Assessment of a new method for the analysis of decomposition gases of polymers by a combining thermogravimetric solid-phase extraction and thermal desorption gas chromatography mass spectrometry.

    Science.gov (United States)

    Duemichen, E; Braun, U; Senz, R; Fabian, G; Sturm, H

    2014-08-08

    For analysis of the gaseous thermal decomposition products of polymers, the common techniques are thermogravimetry, combined with Fourier transformed infrared spectroscopy (TGA-FTIR) and mass spectrometry (TGA-MS). These methods offer a simple approach to the decomposition mechanism, especially for small decomposition molecules. Complex spectra of gaseous mixtures are very often hard to identify because of overlapping signals. In this paper a new method is described to adsorb the decomposition products during controlled conditions in TGA on solid-phase extraction (SPE) material: twisters. Subsequently the twisters were analysed with thermal desorption gas chromatography mass spectrometry (TDS-GC-MS), which allows the decomposition products to be separated and identified using an MS library. The thermoplastics polyamide 66 (PA 66) and polybutylene terephthalate (PBT) were used as example polymers. The influence of the sample mass and of the purge gas flow during the decomposition process was investigated in TGA. The advantages and limitations of the method were presented in comparison to the common analysis techniques, TGA-FTIR and TGA-MS. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Nonlinear dimensionality reduction combining MR imaging with non-imaging information.

    Science.gov (United States)

    Wolz, Robin; Aljabar, Paul; Hajnal, Joseph V; Lötjönen, Jyrki; Rueckert, Daniel

    2012-05-01

    We propose a framework for the extraction of biomarkers from low-dimensional manifolds representing inter-subject brain variation. Manifold coordinates of each image capture information about structural shape and appearance and, when a phenotype exists, about the subject's clinical state. Our framework incorporates subject meta-information into the manifold learning step. Apart from gender and age, information such as genotype or a derived biomarker is often available in clinical studies and can inform the classification of a query subject. Such information, whether discrete or continuous, is used as an additional input to manifold learning, extending the Laplacian Eigenmap objective function and enriching a similarity measure derived from pairwise image similarities. The biomarkers identified with the proposed method are data-driven in contrast to a priori defined biomarkers derived from, e.g., manual or automated segmentations. They form a unified representation of both the imaging and non-imaging measurements, providing a natural use for data analysis and visualization. We test the method to classify subjects with Alzheimer's Disease (AD), mild cognitive impairment (MCI) and healthy controls enrolled in the ADNI study. Non-imaging metadata used are ApoE genotype, a risk factor associated with AD, and the CSF-concentration of Aβ(1-42), an established biomarker for AD. In addition, we use hippocampal volume as a derived imaging-biomarker to enrich the learned manifold. Our classification results compare favorably to what has been reported in a recent meta-analysis using established neuroimaging methods on the same database. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Lung Nodule Image Classification Based on Local Difference Pattern and Combined Classifier.

    Science.gov (United States)

    Mao, Keming; Deng, Zhuofu

    2016-01-01

    This paper proposes a novel lung nodule classification method for low-dose CT images. The method includes two stages. First, Local Difference Pattern (LDP) is proposed to encode the feature representation, which is extracted by comparing intensity difference along circular regions centered at the lung nodule. Then, the single-center classifier is trained based on LDP. Due to the diversity of feature distribution for different class, the training images are further clustered into multiple cores and the multicenter classifier is constructed. The two classifiers are combined to make the final decision. Experimental results on public dataset show the superior performance of LDP and the combined classifier.

  8. Lung Nodule Image Classification Based on Local Difference Pattern and Combined Classifier

    Directory of Open Access Journals (Sweden)

    Keming Mao

    2016-01-01

    Full Text Available This paper proposes a novel lung nodule classification method for low-dose CT images. The method includes two stages. First, Local Difference Pattern (LDP is proposed to encode the feature representation, which is extracted by comparing intensity difference along circular regions centered at the lung nodule. Then, the single-center classifier is trained based on LDP. Due to the diversity of feature distribution for different class, the training images are further clustered into multiple cores and the multicenter classifier is constructed. The two classifiers are combined to make the final decision. Experimental results on public dataset show the superior performance of LDP and the combined classifier.

  9. SPR imaging combined with cyclic voltammetry for the detection of neural activity

    Directory of Open Access Journals (Sweden)

    Hui Li

    2014-03-01

    Full Text Available Surface plasmon resonance (SPR detects changes in refractive index at a metal-dielectric interface. In this study, SPR imaging (SPRi combined with cyclic voltammetry (CV was applied to detect neural activity in isolated bullfrog sciatic nerves. The neural activities induced by chemical and electrical stimulation led to an SPR response, and the activities were recorded in real time. The activities of different parts of the sciatic nerve were recorded and compared. The results demonstrated that SPR imaging combined with CV is a powerful tool for the investigation of neural activity.

  10. Quality Control in Automated Manufacturing Processes – Combined Features for Image Processing

    Directory of Open Access Journals (Sweden)

    B. Kuhlenkötter

    2006-01-01

    Full Text Available In production processes the use of image processing systems is widespread. Hardware solutions and cameras respectively are available for nearly every application. One important challenge of image processing systems is the development and selection of appropriate algorithms and software solutions in order to realise ambitious quality control for production processes. This article characterises the development of innovative software by combining features for an automatic defect classification on product surfaces. The artificial intelligent method Support Vector Machine (SVM is used to execute the classification task according to the combined features. This software is one crucial element for the automation of a manually operated production process. 

  11. Image reconstruction method for electrical capacitance tomography based on the combined series and parallel normalization model

    International Nuclear Information System (INIS)

    Dong, Xiangyuan; Guo, Shuqing

    2008-01-01

    In this paper, a novel image reconstruction method for electrical capacitance tomography (ECT) based on the combined series and parallel model is presented. A regularization technique is used to obtain a stabilized solution of the inverse problem. Also, the adaptive coefficient of the combined model is deduced by numerical optimization. Simulation results indicate that it can produce higher quality images when compared to the algorithm based on the parallel or series models for the cases tested in this paper. It provides a new algorithm for ECT application

  12. Combining region-based and imprecise boundary-based cues for interactive medical image segmentation.

    Science.gov (United States)

    Jones, Jonathan-Lee; Xie, Xianghua; Essa, Ehab

    2014-12-01

    In this paper, we present an approach combining both region selection and user point selection for user-assisted segmentation as either an enclosed object or an open curve, investigate the method of image segmentation in specific medical applications (user-assisted segmentation of the media-adventitia border in intravascular ultrasound images, and lumen border in optical coherence tomography images), and then demonstrate the method with generic images to show how it could be utilized in other types of medical image and is not limited to the applications described. The proposed method combines point-based soft constraint on object boundary and stroke-based regional constraint. The user points act as attraction points and are treated as soft constraints rather than hard constraints that the segmented boundary has to pass through. The user can also use strokes to specify region of interest. The probabilities of region of interest for each pixel are then calculated, and their discontinuity is used to indicate object boundary. The combinations of different types of user constraints and image features allow flexible and robust segmentation, which is formulated as an energy minimization problem on a multilayered graph and is solved using a shortest path search algorithm. We show that this combinatorial approach allows efficient and effective interactive segmentation, which can be used with both open and closed curves to segment a variety of images in different ways. The proposed method is demonstrated in the two medical applications, that is, intravascular ultrasound and optical coherence tomography images, where image artefacts such as acoustic shadow and calcification are commonplace and thus user guidance is desirable. We carried out both qualitative and quantitative analysis of the results for the medical data; comparing the proposed method against a number of interactive segmentation techniques. Copyright © 2014 John Wiley & Sons, Ltd.

  13. High-speed videography combined with an x-ray image intensifier for dynamic radiography

    Energy Technology Data Exchange (ETDEWEB)

    Bryant, L.E. Jr.

    1983-01-01

    The Spin Physics SP-2000 high-speed video system can be combined with an x-ray source, a dynamic event having internal (not directly visible) movement and an x-ray image intensifier to perform dynamic radiography. The cesium iodide input fluor and P-20 output fluor of the image intensifier have rapid decay to allow x-ray imaging up to 12,000 pictures per second. Applications of this technique include internal functioning of a compressor, turbulent-water action, and other mechanical actions.

  14. Noble Gases Trace Earth's Subducted Water Flux

    Science.gov (United States)

    Smye, A.; Jackson, C.; Konrad-Schmolke, M.; Parman, S. W.; Ballentine, C. J.

    2016-12-01

    Volatile elements are transported from Earth's surface reservoirs back into the mantle during subduction of oceanic lithosphere [e.g. 1]. Here, we investigate the degree to which the fate of slab-bound noble gases and water are linked through the subduction process. Both water and noble gases are soluble in ring-structured minerals, such as amphibole, that are common constituents of subducted oceanic lithosphere. Heating and burial during subduction liberates noble gases and water from minerals through a combination of diffusion and dissolution. Combining a kinetic model, parameterized for noble gas fractionation in amphibole [2], with thermodynamic phase equilibria calculations, we quantify the effect of subduction dehydration on the elemental composition of slab-bound noble gases. Results show that post-arc slab water and noble gas fluxes are highly correlated. Hot subduction zones, which likely dominate over geologic history, efficiently remove noble gases and water from the down-going slab; furthermore, kinetic fractionation of noble gases is predicted to occur beneath the forearc. Conversely, hydrated portions of slab mantle in cold subduction zones transport noble gases and water to depths exceeding 200 km. Preservation of seawater-like abundances of Ar, Kr and Xe in the convecting mantle [1] implies that recycling of noble gases and water occurred during cold subduction and that the subduction efficiency of these volatile elements has increased over geological time, driven by secular cooling of the mantle. [1] Holland, G. and Ballentine, C. (2006). Nature 441, 186-191. [2] Jackson et al. (2013). Nat.Geosci. 6, 562-565.

  15. MR imaging findings in subacute combined degeneration of the spinal cord: a case report

    International Nuclear Information System (INIS)

    Kim, Ki Jun; Lee, Jae Hee; Lee, Sung Yong; Chung, Sung Woo

    2000-01-01

    Vitamin B12 deficiency can cause neurologic complications in the spinal cord, brain, and optic and peripheral nerves. Subacute combined degeneration is a rare disease of demyelinating lesions of the spinal cord, affecting mainly the posterior and lateral columns of the thoracic cord. We report the MR imaging findings of a case of subacute combined degeneration of the spinal cord in a patient with vitamin B12 deficiency and mega loblastic anemia. (author)

  16. Biomedical Imaging Modality Classification Using Combined Visual Features and Textual Terms

    Directory of Open Access Journals (Sweden)

    Xian-Hua Han

    2011-01-01

    extraction from medical images and fuses the different extracted visual features and textual feature for modality classification. To extract visual features from the images, we used histogram descriptor of edge, gray, or color intensity and block-based variation as global features and SIFT histogram as local feature. For textual feature of image representation, the binary histogram of some predefined vocabulary words from image captions is used. Then, we combine the different features using normalized kernel functions for SVM classification. Furthermore, for some easy misclassified modality pairs such as CT and MR or PET and NM modalities, a local classifier is used for distinguishing samples in the pair modality to improve performance. The proposed strategy is evaluated with the provided modality dataset by ImageCLEF 2010.

  17. Iron Oxide Nanoradiomaterials: Combining Nanoscale Properties with Radioisotopes for Enhanced Molecular Imaging.

    Science.gov (United States)

    Pellico, Juan; Llop, Jordi; Fernández-Barahona, Irene; Bhavesh, Riju; Ruiz-Cabello, Jesús; Herranz, Fernando

    2017-01-01

    The combination of the size-dependent properties of nanomaterials with radioisotopes is emerging as a novel tool for molecular imaging. There are numerous examples already showing how the controlled synthesis of nanoparticles and the incorporation of a radioisotope in the nanostructure offer new features beyond the simple addition of different components. Among the different nanomaterials, iron oxide-based nanoparticles are the most used in imaging because of their versatility. In this review, we will study the different radioisotopes for biomedical imaging, how to incorporate them within the nanoparticles, and what applications they can be used for. Our focus is directed towards what is new in this field, what the nanoparticles can offer to the field of nuclear imaging, and the radioisotopes hybridized with nanomaterials for use in molecular imaging.

  18. Iron Oxide Nanoradiomaterials: Combining Nanoscale Properties with Radioisotopes for Enhanced Molecular Imaging

    Directory of Open Access Journals (Sweden)

    Juan Pellico

    2017-01-01

    Full Text Available The combination of the size-dependent properties of nanomaterials with radioisotopes is emerging as a novel tool for molecular imaging. There are numerous examples already showing how the controlled synthesis of nanoparticles and the incorporation of a radioisotope in the nanostructure offer new features beyond the simple addition of different components. Among the different nanomaterials, iron oxide-based nanoparticles are the most used in imaging because of their versatility. In this review, we will study the different radioisotopes for biomedical imaging, how to incorporate them within the nanoparticles, and what applications they can be used for. Our focus is directed towards what is new in this field, what the nanoparticles can offer to the field of nuclear imaging, and the radioisotopes hybridized with nanomaterials for use in molecular imaging.

  19. Photoacoustic imaging in scattering media by combining a correlation matrix filter with a time reversal operator.

    Science.gov (United States)

    Rui, Wei; Tao, Chao; Liu, Xiaojun

    2017-09-18

    Acoustic scattering medium is a fundamental challenge for photoacoustic imaging. In this study, we reveal the different coherent properties of the scattering photoacoustic waves and the direct photoacoustic waves in a matrix form. Direct waves show a particular coherence on the antidiagonals of the matrix, whereas scattering waves do not. Based on this property, a correlation matrix filter combining with a time reversal operator is proposed to preserve the direct waves and recover the image behind a scattering layer. Both numerical simulations and photoacoustic imaging experiments demonstrate that the proposed approach effectively increases the image contrast and decreases the background speckles in a scattering medium. This study might improve the quality of photoacoustic imaging in an acoustic scattering environment and extend its applications.

  20. Combination of Narrow-band Imaging and Autofluorescence Imaging 
Videobronchoscopy in the Assessment of Lung Cancer

    Directory of Open Access Journals (Sweden)

    Zhongbo CHEN

    2013-06-01

    Full Text Available Background and objective Narrow-band imaging (NBI and autofluorescence imaging (AFI are new bronchoscopy technologies that are important in lung cancer diagnosis. The aim of this study is to determine whether or not the combination of these two technologies can improve sensitivity and specificity of lung cancer diagnosis. Methods A total of 137 patients who manifested symptoms of lung cancer were investigated in this project. All of the examinations were performed based on an Olympus Evis Lucera bronchoscopy system. The patients were examined by white light bronchoscopy (WLB, NBI and AFI. At least three biopsies from body parts visualized as lesions were obtained from each patient. Results WLB sensitivity and specificity were 56.6% and 62.5%, respectively. NBI sensitivity and specificity were 71.3% and 75.0%, respectively. AFI sensitivity and specificity were 82.2% and 25.0%, respectively. The sensitivity and the specificity of the combined NBI and AFI were 94.6% and 87.5%, respectively. The sensitivity and the specificity of the combined NBI and AFI were significantly higher than those of AFI alone (P<0.01. Likewise, the sensitivity and the specificity of the combined NBI and AFI were significantly higher than those of NBI alone (P<0.05. Conclusion NBI or AFI exhibited higher sensitivity of lung cancer diagnosis than WLB. Combined NBI and AFI also showed significantly higher sensitivity and specificity than NBI or AFI.

  1. Embodied memory: effective and stable perception by combining optic flow and image structure.

    Science.gov (United States)

    Pan, Jing Samantha; Bingham, Ned; Bingham, Geoffrey P

    2013-12-01

    Visual perception studies typically focus either on optic flow structure or image structure, but not on the combination and interaction of these two sources of information. Each offers unique strengths in contrast to the other's weaknesses. Optic flow yields intrinsically powerful information about 3D structure, but is ephemeral. It ceases when motion stops. Image structure is less powerful in specifying 3D structure, but is stable. It remains when motion stops. Optic flow and image structure are intrinsically related in vision because the optic flow carries one image to the next. This relation is especially important in the context of progressive occlusion, in which optic flow provides information about the location of targets hidden in subsequent image structure. In four experiments, we investigated the role of image structure in "embodied memory" in contrast to memory that is only in the head. We found that either optic flow (Experiment 1) or image structure (Experiment 2) alone were relatively ineffective, whereas the combination was effective and, in contrast to conditions requiring reliance on memory-in-the-head, much more stable over extended time (Experiments 2 through 4). Limits well documented for visual short memory (that is, memory-in-the-head) were strongly exceeded by embodied memory. The findings support J. J. Gibson's (1979/1986, The Ecological Approach to Visual Perception, Boston, MA, Houghton Mifflin) insights about progressive occlusion and the embodied nature of perception and memory.

  2. Development of an Anthropomorphic Breast Phantom for Combined PET, B-Mode Ultrasound and Elastographic Imaging

    CERN Document Server

    Dang, J; Tavernier, S; Lasaygues, P; Mensah, S; Zhang, D C; Auffray, E; Frisch, B; Varela, J; Wan, M X; Felix, N

    2011-01-01

    Combining the advantages of different imaging modalities leads to improved clinical results. For example, ultrasound provides good real-time structural information without any radiation and PET provides sensitive functional information. For the ongoing ClearPEM-Sonic project combining ultrasound and PET for breast imaging, we developed a dual-modality PET/Ultrasound (US) phantom. The phantom reproduces the acoustic and elastic properties of human breast tissue and allows labeling the different tissues in the phantom with different concentrations of FDG. The phantom was imaged with a whole-body PET/CT and with the Supersonic Imagine Aixplorer system. This system allows both B-mode US and shear wave elastographic imaging. US elastography is a new imaging method for displaying the tissue elasticity distribution. It was shown to be useful in breast imaging. We also tested the phantom with static elastography. A 6D magnetic positioning system allows fusing the images obtained with the two modalities. ClearPEM-Soni...

  3. Multitask Imaging Monitor for Surgical Navigation: Combination of Touchless Interface and Head-Mounted Display.

    Science.gov (United States)

    Yoshida, Soichiro; Ito, Masaya; Tatokoro, Manabu; Yokoyama, Minato; Ishioka, Junichiro; Matsuoka, Yoh; Numao, Noboru; Saito, Kazutaka; Fujii, Yasuhisa; Kihara, Kazunori

    2017-01-01

    As a result of the dramatic improvements in the resolution, wearability, and weight of head-mounted displays (HMDs), they have become increasingly applied in the medical field as personal imaging monitors. The combined use of a multiplexer with an HMD allows the wearer to simultaneously and seamlessly monitor multiple streams of imaging information through the HMD. We developed a multitask imaging monitor for surgical navigation by combining a touchless surgical imaging control system with an HMD. This system is composed of a standard color digital video camera mounted on the HMD and computer software that enables the identification of the number of pictured fingertips from the video camera image. The HMD wearer uses this information as a touchless interface for the operating multiplexer, which can control the arrays and types of imaging information displayed on the HMD. We used this system in an experimental demonstration during a single-port gasless partial nephrectomy. The use of this multitask imaging monitor using a touchless interface would refine the surgical workflow, especially during surgical navigation. © 2015 S. Karger AG, Basel.

  4. Extended Field Laser Confocal Microscopy (EFLCM): Combining automated Gigapixel image capture with in silico virtual microscopy

    International Nuclear Information System (INIS)

    Flaberg, Emilie; Sabelström, Per; Strandh, Christer; Szekely, Laszlo

    2008-01-01

    Confocal laser scanning microscopy has revolutionized cell biology. However, the technique has major limitations in speed and sensitivity due to the fact that a single laser beam scans the sample, allowing only a few microseconds signal collection for each pixel. This limitation has been overcome by the introduction of parallel beam illumination techniques in combination with cold CCD camera based image capture. Using the combination of microlens enhanced Nipkow spinning disc confocal illumination together with fully automated image capture and large scale in silico image processing we have developed a system allowing the acquisition, presentation and analysis of maximum resolution confocal panorama images of several Gigapixel size. We call the method Extended Field Laser Confocal Microscopy (EFLCM). We show using the EFLCM technique that it is possible to create a continuous confocal multi-colour mosaic from thousands of individually captured images. EFLCM can digitize and analyze histological slides, sections of entire rodent organ and full size embryos. It can also record hundreds of thousands cultured cells at multiple wavelength in single event or time-lapse fashion on fixed slides, in live cell imaging chambers or microtiter plates. The observer independent image capture of EFLCM allows quantitative measurements of fluorescence intensities and morphological parameters on a large number of cells. EFLCM therefore bridges the gap between the mainly illustrative fluorescence microscopy and purely quantitative flow cytometry. EFLCM can also be used as high content analysis (HCA) instrument for automated screening processes

  5. Combining Global and Local Information for Knowledge-Assisted Image Analysis and Classification

    Directory of Open Access Journals (Sweden)

    Mezaris V

    2007-01-01

    Full Text Available A learning approach to knowledge-assisted image analysis and classification is proposed that combines global and local information with explicitly defined knowledge in the form of an ontology. The ontology specifies the domain of interest, its subdomains, the concepts related to each subdomain as well as contextual information. Support vector machines (SVMs are employed in order to provide image classification to the ontology subdomains based on global image descriptions. In parallel, a segmentation algorithm is applied to segment the image into regions and SVMs are again employed, this time for performing an initial mapping between region low-level visual features and the concepts in the ontology. Then, a decision function, that receives as input the computed region-concept associations together with contextual information in the form of concept frequency of appearance, realizes image classification based on local information. A fusion mechanism subsequently combines the intermediate classification results, provided by the local- and global-level information processing, to decide on the final image classification. Once the image subdomain is selected, final region-concept association is performed using again SVMs and a genetic algorithm (GA for optimizing the mapping between the image regions and the selected subdomain concepts taking into account contextual information in the form of spatial relations. Application of the proposed approach to images of the selected domain results in their classification (i.e., their assignment to one of the defined subdomains and the generation of a fine granularity semantic representation of them (i.e., a segmentation map with semantic concepts attached to each segment. Experiments with images from the personal collection domain, as well as comparative evaluation with other approaches of the literature, demonstrate the performance of the proposed approach.

  6. A comparative study of scintillator combining methods for flat-panel X-ray image sensors

    Science.gov (United States)

    Kim, M. S.; Lim, K. T.; Kim, G.; Cho, G.

    2018-02-01

    An X-ray transmission imaging based on scintillation detection method is the most widely used radiation technique particularly in the medical and industrial areas. As the name suggests, scintillation detection uses a scintillator as an intermediate material to convert incoming radiation into visible-light particles. Among different types of scintillators, CsI(Tl) in a columnar configuration is the most popular type used for applications that require an energy less than 150 keV due to its capability in obtaining a high spatial resolution with a reduced light spreading effect. In this study, different methods in combining a scintillator with a light-receiving unit are investigated and their relationships are given in terms of the image quality. Three different methods of combining a scintillator with a light-receiving unit are selected to investigate their performance in X-ray imaging: upward or downward oriented needles structure of CsI(Tl), coating layer deposition around CsI(Tl), and insertion of FOP. A charge-coupled device was chosen to serve as the light-receiving unit for the proposed system. From the result, the difference of needle directions in CsI(Tl) had no significant effects in the X-ray image. In contrast, deposition of the coating material around CsI(Tl) showed 17.3% reduction in the DQE. Insertion of the FOP increased the spatial resolution by 38%, however, it decreased the light yield in the acquired image by 56%. In order to have the maximum scintillation performance in X-ray imaging, not only the reflection material but also the bonding method must be considered when combining the scintillator with the light-receiving unit. In addition, the use of FOP should be carefully decided based on the purpose of X-ray imaging, e.g., image sharpness or SNR.

  7. Self-esteem threat combined with exposure to thin media images leads to body image compensatory self-enhancement.

    Science.gov (United States)

    Jarry, Josée L; Kossert, Amy L

    2007-03-01

    This study examined the effect of a self-esteem threat combined with exposure to thin images on body image (BI) satisfaction and investment. Female participants (N=94) received a self-esteem threat consisting of false failure feedback or received false success feedback on an intellectual task allegedly highly predictive of academic and professional success. They then viewed media images featuring thin models or products. After viewing thin models, women who had received failure feedback declared themselves more satisfied about their appearance and less invested in it than did women who had received success feedback. These results suggest that exposure to the thin ideal may inspire women experiencing self-esteem threats to use appearance as an alternative source of worth, thus maintaining their global esteem through BI compensatory self-enhancement. Potential long-term implications of this strategy, such as a paradoxical increase in BI investment and the development of eating pathology, are discussed.

  8. Improved localization of cellular membrane receptors using combined fluorescence microscopy and simultaneous topography and recognition imaging

    Energy Technology Data Exchange (ETDEWEB)

    Duman, M; Pfleger, M; Chtcheglova, L A; Neundlinger, I; Bozna, B L; Ebner, A; Schuetz, G J; Hinterdorfer, P [Institute for Biophysics, University of Linz, Altenbergerstrasse 69, A-4040 Linz (Austria); Zhu, R; Mayer, B [Christian Doppler Laboratory for Nanoscopic Methods in Biophysics, Institute for Biophysics, University of Linz, Altenbergerstrasse 69, A-4040 Linz (Austria); Rankl, C; Moertelmaier, M; Kada, G; Kienberger, F [Agilent Technologies Austria GmbH, Aubrunnerweg 11, A-4040 Linz (Austria); Salio, M; Shepherd, D; Polzella, P; Cerundolo, V [Cancer Research UK Tumor Immunology Group, Weatherall Institute of Molecular Medicine, Nuffield Department of Medicine, University of Oxford, Oxford OX3 9DS (United Kingdom); Dieudonne, M, E-mail: ferry_kienberger@agilent.com [Agilent Technologies Belgium, Wingepark 51, Rotselaar, AN B-3110 (Belgium)

    2010-03-19

    The combination of fluorescence microscopy and atomic force microscopy has a great potential in single-molecule-detection applications, overcoming many of the limitations coming from each individual technique. Here we present a new platform of combined fluorescence and simultaneous topography and recognition imaging (TREC) for improved localization of cellular receptors. Green fluorescent protein (GFP) labeled human sodium-glucose cotransporter (hSGLT1) expressed Chinese Hamster Ovary (CHO) cells and endothelial cells (MyEnd) from mouse myocardium stained with phalloidin-rhodamine were used as cell systems to study AFM topography and fluorescence microscopy on the same surface area. Topographical AFM images revealed membrane features such as lamellipodia, cytoskeleton fibers, F-actin filaments and small globular structures with heights ranging from 20 to 30 nm. Combined fluorescence and TREC imaging was applied to detect density, distribution and localization of YFP-labeled CD1d molecules on {alpha}-galactosylceramide ({alpha}GalCer)-loaded THP1 cells. While the expression level, distribution and localization of CD1d molecules on THP1 cells were detected with fluorescence microscopy, the nanoscale distribution of binding sites was investigated with molecular recognition imaging by using a chemically modified AFM tip. Using TREC on the inverted light microscope, the recognition sites of cell receptors were detected in recognition images with domain sizes ranging from {approx} 25 to {approx} 160 nm, with the smaller domains corresponding to a single CD1d molecule.

  9. Combining low level features and visual attributes for VHR remote sensing image classification

    Science.gov (United States)

    Zhao, Fumin; Sun, Hao; Liu, Shuai; Zhou, Shilin

    2015-12-01

    Semantic classification of very high resolution (VHR) remote sensing images is of great importance for land use or land cover investigation. A large number of approaches exploiting different kinds of low level feature have been proposed in the literature. Engineers are often frustrated by their conclusions and a systematic assessment of various low level features for VHR remote sensing image classification is needed. In this work, we firstly perform an extensive evaluation of eight features including HOG, dense SIFT, SSIM, GIST, Geo color, LBP, Texton and Tiny images for classification of three public available datasets. Secondly, we propose to transfer ground level scene attributes to remote sensing images. Thirdly, we combine both low-level features and mid-level visual attributes to further improve the classification performance. Experimental results demonstrate that i) Dene SIFT and HOG features are more robust than other features for VHR scene image description. ii) Visual attribute competes with a combination of low level features. iii) Multiple feature combination achieves the best performance under different settings.

  10. The Dual Codebook : Combining Bags of Visual Words in Image Classification

    NARCIS (Netherlands)

    Maas, Jonathan L.; Okafor, Emmanuel; Wiering, Marco

    2016-01-01

    In this paper, we evaluate the performance of two conventional bag of words approaches, using two basic local feature descriptors, to perform image classification. These approaches are compared to a novel design which combines two bags of visual words, using two different feature descriptors. The

  11. Magnetic Resonance Imaging Volumetric Analysis of the Putamen in Children with ADHD: Combined Type versus Control

    Science.gov (United States)

    Wellington, Tasha McMahon; Semrud-Clikeman, Margaret; Gregory, Amanda Louise; Murphy, Jennifer Mary; Lancaster, Jack Lynn

    2006-01-01

    Objective: Volumetric differences in the putamen of boys with ADHD combined subtype with psychopathic traits and controls are investigated. Method: The putamen in 24 archival magnetic resonance imaging scans of 12 boys in residential treatment with symptoms of ADHD and psychopathic traits and 12 community control boys are analyzed using Display…

  12. Polymerized LB Films Imaged with a Combined Atomic Force Microscope-Fluorescence Microscope

    NARCIS (Netherlands)

    Putman, C.A.J.; Putman, Constant A.J.; Hansma, Helen G.; Gaub, Hermann E.; Hansma, Paul K.

    1992-01-01

    The first results obtained with a new stand-alone atomic force microscope (AFM) integrated with a standard Zeiss optical fluorescence microscope are presented. The optical microscope allows location and selection of objects to be imaged with the high-resolution AFM. Furthermore, the combined

  13. Combined neutron and x-ray imaging at the National Ignition Facility (invited).

    Science.gov (United States)

    Danly, C R; Christensen, K; Fatherley, V E; Fittinghoff, D N; Grim, G P; Hibbard, R; Izumi, N; Jedlovec, D; Merrill, F E; Schmidt, D W; Simpson, R A; Skulina, K; Volegov, P L; Wilde, C H

    2016-11-01

    X-ray and neutrons are commonly used to image inertial confinement fusion implosions, providing key diagnostic information on the fuel assembly of burning deuterium-tritium (DT) fuel. The x-ray and neutron data provided are complementary as the production of neutrons and x-rays occurs from different physical processes, but typically these two images are collected from different views with no opportunity for co-registration of the two images. Neutrons are produced where the DT fusion fuel is burning; X-rays are produced in regions corresponding to high temperatures. Processes such as mix of ablator material into the hotspot can result in increased x-ray production and decreased neutron production but can only be confidently observed if the two images are collected along the same line of sight and co-registered. To allow direct comparison of x-ray and neutron data, a combined neutron x-ray imaging system has been tested at Omega and installed at the National Ignition Facility to collect an x-ray image along the currently installed neutron imaging line of sight. This system is described, and initial results are presented along with prospects for definitive coregistration of the images.

  14. The Two-Dimensional Wavelet Transform De-noising and Combining with Side Scan Sonar Image

    Directory of Open Access Journals (Sweden)

    Muhammad Zainuddin Lubis

    2017-05-01

    Full Text Available This paper puts forward an image de-noising method based on 2D wavelet transform with the application of the method in seabed identification data collection system. Two-dimensional haar wavelets in image processing presents a unified framework for wavelet image compression and combining with side scan sonar image. Seabed identification target have 7 target detection in side scan sonar imagery result.  The vibration signals were analyzed to perform fault diagnosis. The obtained signal was time-domain signal. The experiment result shows that the application of 2D wavelet transform image de-noising algorithm can achieve good subjective and objective image quality and help to collect high quality data and analyze the images for the data center with optimum effects, the features from time-domain signal were extracted. 3 vectors were formed which are v1, v2, v3. In Haar wavelet retained energy is 93.8 %, so from the results, it has been concluded that Haar wavelet transform shows the best results in terms of Energy from De-noised Image processing with side scan sonar imagery.

  15. The Two-Dimensional Wavelet Transform De-noising and Combining with Side Scan Sonar Image

    Directory of Open Access Journals (Sweden)

    Muhammad Zainuddin Lubis

    2017-04-01

    Full Text Available This paper puts forward an image de-noising method based on 2D wavelet transform with the application of the method in seabed identification data collection system. Two-dimensional haar wavelets in image processing presents a unified framework for wavelet image compression and combining with side scan sonar image. Seabed identification target have 7 target detection in side scan sonar imagery result. The vibration signals were analyzed to perform fault diagnosis. The obtained signal was time-domain signal. The experiment result shows that the application of 2D wavelet transform image de-noising algorithm can achieve good subjective and objective image quality and help to collect high quality data and analyze the images for the data center with optimum effects, the features from time-domain signal were extracted. 3 vectors were formed which are v1, v2, v3. In Haar wavelet retained energy is 93.8 %, so from the results, it has been concluded that Haar wavelet transform shows the best results in terms of Energy from De-noised Image processing with side scan sonar imagery.

  16. A Novel Segmentation Approach Combining Region- and Edge-Based Information for Ultrasound Images

    Directory of Open Access Journals (Sweden)

    Yaozhong Luo

    2017-01-01

    Full Text Available Ultrasound imaging has become one of the most popular medical imaging modalities with numerous diagnostic applications. However, ultrasound (US image segmentation, which is the essential process for further analysis, is a challenging task due to the poor image quality. In this paper, we propose a new segmentation scheme to combine both region- and edge-based information into the robust graph-based (RGB segmentation method. The only interaction required is to select two diagonal points to determine a region of interest (ROI on the original image. The ROI image is smoothed by a bilateral filter and then contrast-enhanced by histogram equalization. Then, the enhanced image is filtered by pyramid mean shift to improve homogeneity. With the optimization of particle swarm optimization (PSO algorithm, the RGB segmentation method is performed to segment the filtered image. The segmentation results of our method have been compared with the corresponding results obtained by three existing approaches, and four metrics have been used to measure the segmentation performance. The experimental results show that the method achieves the best overall performance and gets the lowest ARE (10.77%, the second highest TPVF (85.34%, and the second lowest FPVF (4.48%.

  17. Combining T2-weighted with dynamic MR images for computerized classification of prostate lesions

    Science.gov (United States)

    Vos, Pieter C.; Hambrock, Thomas; Barentsz, Jelle O.; Huisman, Henkjan J.

    2008-03-01

    In this study, we investigate the diagnostic performance of our CAD system when discriminating prostate cancer from benign lesions and normal peripheral zone using registered multi-modal images. We have developed a method that automatically extracts quantitative T2 values out of acquired T2-w images and evaluated its additional value to the discriminating performance of our CAD system. This study addresses 2 issues when using both T2-w and dynamic MR images for the characterization of prostate lesions. Firstly, T2-w images do not provide quantitative values, and secondly, images can be misaligned due to patient movements. To compensate, a mutual information registration strategy is performed after which T2 values are estimated using the acquired proton density images. From the resulted quantitative T2 maps as well as the dynamic images relevant features were extracted for training a support vector machine as classfier. The output of the classifier was used as a measure of likelihood of malignancy. General performance of the scheme was evaluated using the area under the ROC curve. We conclude that it is feasible to automatically extract diagnostic T2 values out of acquired T2-w images. Furthermore, a discriminating performance of 0.75 (0.66-0.85) was obtained when only using T2-values as feature. Combining the T2 values with pharmacokinetic parameters did not increase diagnostic performance in a pilot study.

  18. Combining multiset resolution and segmentation for hyperspectral image analysis of biological tissues.

    Science.gov (United States)

    Piqueras, S; Krafft, C; Beleites, C; Egodage, K; von Eggeling, F; Guntinas-Lichius, O; Popp, J; Tauler, R; de Juan, A

    2015-06-30

    Hyperspectral images can provide useful biochemical information about tissue samples. Often, Fourier transform infrared (FTIR) images have been used to distinguish different tissue elements and changes caused by pathological causes. The spectral variation between tissue types and pathological states is very small and multivariate analysis methods are required to describe adequately these subtle changes. In this work, a strategy combining multivariate curve resolution-alternating least squares (MCR-ALS), a resolution (unmixing) method, which recovers distribution maps and pure spectra of image constituents, and K-means clustering, a segmentation method, which identifies groups of similar pixels in an image, is used to provide efficient information on tissue samples. First, multiset MCR-ALS analysis is performed on the set of images related to a particular pathology status to provide basic spectral signatures and distribution maps of the biological contributions needed to describe the tissues. Later on, multiset segmentation analysis is applied to the obtained MCR scores (concentration profiles), used as compressed initial information for segmentation purposes. The multiset idea is transferred to perform image segmentation of different tissue samples. Doing so, a difference can be made between clusters associated with relevant biological parts common to all images, linked to general trends of the type of samples analyzed, and sample-specific clusters, that reflect the natural biological sample-to-sample variability. The last step consists of performing separate multiset MCR-ALS analyses on the pixels of each of the relevant segmentation clusters for the pathology studied to obtain a finer description of the related tissue parts. The potential of the strategy combining multiset resolution on complete images, multiset segmentation and multiset local resolution analysis will be shown on a study focused on FTIR images of tissue sections recorded on inflamed and non

  19. A combined method for correlative 3D imaging of biological samples from macro to nano scale

    Science.gov (United States)

    Kellner, Manuela; Heidrich, Marko; Lorbeer, Raoul-Amadeus; Antonopoulos, Georgios C.; Knudsen, Lars; Wrede, Christoph; Izykowski, Nicole; Grothausmann, Roman; Jonigk, Danny; Ochs, Matthias; Ripken, Tammo; Kühnel, Mark P.; Meyer, Heiko

    2016-10-01

    Correlative analysis requires examination of a specimen from macro to nano scale as well as applicability of analytical methods ranging from morphological to molecular. Accomplishing this with one and the same sample is laborious at best, due to deformation and biodegradation during measurements or intermediary preparation steps. Furthermore, data alignment using differing imaging techniques turns out to be a complex task, which considerably complicates the interconnection of results. We present correlative imaging of the accessory rat lung lobe by combining a modified Scanning Laser Optical Tomography (SLOT) setup with a specially developed sample preparation method (CRISTAL). CRISTAL is a resin-based embedding method that optically clears the specimen while allowing sectioning and preventing degradation. We applied and correlated SLOT with Multi Photon Microscopy, histological and immunofluorescence analysis as well as Transmission Electron Microscopy, all in the same sample. Thus, combining CRISTAL with SLOT enables the correlative utilization of a vast variety of imaging techniques.

  20. Combining voxel-based morphometry and diffusion tensor imaging to detect age-related brain changes.

    Science.gov (United States)

    Lehmbeck, Jan T; Brassen, Stefanie; Weber-Fahr, Wolfgang; Braus, Dieter F

    2006-04-03

    The present study combined optimized voxel-based morphometry and diffusion tensor imaging to detect age-related brain changes. We compared grey matter density maps (grey matter voxel-based morphometry) and white matter fractional anisotropy maps (diffusion tensor imaging-voxel-based morphometry) between two groups of 17 younger and 17 older women. Older women exhibited reduced white matter fractional anisotropy as well as decreased grey matter density most prominently in the frontal, limbic, parietal and temporal lobes. A discriminant analysis identified four frontal and limbic grey and white matter areas that separated the two groups most effectively. We conclude that grey matter voxel-based morphometry and diffusion tensor imaging voxel-based morphometry are well suited for the detection of age-related changes and their combination provides high accuracy when detecting the neural correlates of aging.

  1. Neutron, fluorescence, and optical imaging: An in situ combination of complementary techniques

    International Nuclear Information System (INIS)

    Wagner, D.; Egelhaaf, S. U.; Hermes, H. E.; Börgardts, M.; Müller, T. J. J.; Grünzweig, C.; Lehmann, E.

    2015-01-01

    An apparatus which enables the simultaneous combination of three complementary imaging techniques, optical imaging, fluorescence imaging, and neutron radiography, is presented. While each individual technique can provide information on certain aspects of the sample and their time evolution, a combination of the three techniques in one setup provides a more complete and consistent data set. The setup can be used in transmission and reflection modes and thus with optically transparent as well as opaque samples. Its capabilities are illustrated with two examples. A polymer hydrogel represents a transparent sample and the diffusion of fluorescent particles into and through this polymer matrix is followed. In reflection mode, the absorption of solvent by a nile red-functionalized mesoporous silica powder and the corresponding change in fluorescent signal are studied

  2. Image Denoising Algorithm Combined with SGK Dictionary Learning and Principal Component Analysis Noise Estimation

    Directory of Open Access Journals (Sweden)

    Wenjing Zhao

    2018-01-01

    Full Text Available SGK (sequential generalization of K-means dictionary learning denoising algorithm has the characteristics of fast denoising speed and excellent denoising performance. However, the noise standard deviation must be known in advance when using SGK algorithm to process the image. This paper presents a denoising algorithm combined with SGK dictionary learning and the principal component analysis (PCA noise estimation. At first, the noise standard deviation of the image is estimated by using the PCA noise estimation algorithm. And then it is used for SGK dictionary learning algorithm. Experimental results show the following: (1 The SGK algorithm has the best denoising performance compared with the other three dictionary learning algorithms. (2 The SGK algorithm combined with PCA is superior to the SGK algorithm combined with other noise estimation algorithms. (3 Compared with the original SGK algorithm, the proposed algorithm has higher PSNR and better denoising performance.

  3. Combining Image and Non-Image Data for Automatic Detection of Retina Disease in a Telemedicine Network

    Energy Technology Data Exchange (ETDEWEB)

    Aykac, Deniz [ORNL; Chaum, Edward [University of Tennessee, Knoxville (UTK); Fox, Karen [Delta Health Alliance; Garg, Seema [University of North Carolina; Giancardo, Luca [ORNL; Karnowski, Thomas Paul [ORNL; Li, Yaquin [University of Tennessee, Knoxville (UTK); Nichols, Trent L [ORNL; Tobin Jr, Kenneth William [ORNL

    2011-01-01

    A telemedicine network with retina cameras and automated quality control, physiological feature location, and lesion/anomaly detection is a low-cost way of achieving broad-based screening for diabetic retinopathy (DR) and other eye diseases. In the process of a routine eye-screening examination, other non-image data is often available which may be useful in automated diagnosis of disease. In this work, we report on the results of combining this non-image data with image data, using the protocol and processing steps of a prototype system for automated disease diagnosis of retina examinations from a telemedicine network. The system includes quality assessments, automated physiology detection, and automated lesion detection to create an archive of known cases. Non-image data such as diabetes onset date and hemoglobin A1c (HgA1c) for each patient examination are included as well, and the system is used to create a content-based image retrieval engine capable of automated diagnosis of disease into 'normal' and 'abnormal' categories. The system achieves a sensitivity and specificity of 91.2% and 71.6% using hold-one-out validation testing.

  4. Hypersonics and rarefied gases

    Science.gov (United States)

    Lengrand, Jean-Claude; Allegre, Jean; Raffin, Michel

    1987-10-01

    A molecular approach to the dynamics of rarefied gases is used to solve problems in the modeling of hypersonic asymmetric flows. The microscopic, molecular, macroscopic, continuous, and hydrodynamic approaches are compared. Application of the Monte Carlo method to the simulation of intermolecular collisions, the gas-surface interaction, and hypersonic flows is considered. The use of experimental methods such as wind tunnels, flow visualizations, hot-wire techniques, laser velocimetry, and electron beam sensors for the study of real phenomena related to rarefied gases and for the validation of the calculation methods is also discussed.

  5. On the dissolution of vapors and gases.

    Science.gov (United States)

    Wüstneck, N; Wüstneck, R; Pison, U; Möhwald, H

    2007-02-13

    The captive bubble technique in combination with axisymmetric drop shape analysis (ADSA-CB) and with micro gas chromatography is used to study the dynamics of dissolution of different gases and vapors in water in situ. The technique yields the changes in the interfacial tension and bubble volume and surface. As examples, the dissolution of methanol and hexane vapors, inhaled anesthetic vapors, and gases, that is, diethyl ether, chloroform, isoflurane, enflurane, sevoflurane, desflurane, N2O, and xenon, and as nonimmobilizers perfluoropentane and 1,1,2-trichloro-1,2,2-trifluoro-ethane (R113) were investigated. The examination of interfacial tension-time and bubble volume-time functions permits us to distinguish between water-soluble and -insoluble substances, gases, and vapors. Vapors and gases generally differ in terms of the strength of their intermolecular interactions. The main difference between dissolution processes of gases and vapors is that, during the entire process of gas dissolution, no surface tension change occurs. In contrast, during vapor dissolution the surface tension drops immediately and decreases continuously until it reaches the equilibrium surface tension of water at the end of dissolution. The results of this study show that it is possible to discriminate anesthetic vapors from anesthetic gases and nonimmobilizers by comparing their dissolution dynamics. The nonimmobilizers have extremely low or no solubility in water and change the surface tension only negligibly. By use of newly defined molecular dissolution/diffusion coefficients, a simple model for the determination of partition coefficients is developed.

  6. Gold sputtered fiducial markers for combined secondary ion mass spectrometry and MALDI imaging of tissue samples.

    Science.gov (United States)

    Ogrinc Potočnik, Nina; Škrášková, Karolina; Flinders, Bryn; Pelicon, Primož; Heeren, Ron M A

    2014-07-15

    Mass spectrometry imaging (MSI) is a label free technique capable of providing simultaneous identification and localization of biomolecules. A multimodal approach is required that allows for the study of the complexity of biological tissue samples to overcome the limitations of a single MSI technique. Secondary ion mass spectrometry (SIMS) allows for high spatial resolution imaging while matrix-assisted laser desorption (MALDI) offers a significantly wider mass range. The combination of coregistered SIMS and MALDI images results in detailed and unique biomolecular information. In this Technical Note, we describe how gold sputtered/implanted fiducial markers (FM) are created and can be used to ensure a proper overlay and coregistration of the two-dimensional images provided by the two MSI modalities.

  7. Hyperspectral Image Classification Based on the Combination of Spatial-spectral Feature and Sparse Representation

    Directory of Open Access Journals (Sweden)

    YANG Zhaoxia

    2015-07-01

    Full Text Available In order to avoid the problem of being over-dependent on high-dimensional spectral feature in the traditional hyperspectral image classification, a novel approach based on the combination of spatial-spectral feature and sparse representation is proposed in this paper. Firstly, we extract the spatial-spectral feature by reorganizing the local image patch with the first d principal components(PCs into a vector representation, followed by a sorting scheme to make the vector invariant to local image rotation. Secondly, we learn the dictionary through a supervised method, and use it to code the features from test samples afterwards. Finally, we embed the resulting sparse feature coding into the support vector machine(SVM for hyperspectral image classification. Experiments using three hyperspectral data show that the proposed method can effectively improve the classification accuracy comparing with traditional classification methods.

  8. Combined classical spindle cell/pleomorphic lipoma spectrum imaging and clinical data

    Energy Technology Data Exchange (ETDEWEB)

    Younan, Yara; Gonzalez, Felix; Umpierrez, Monica; Singer, Adam D. [Emory University Hospital, Department of Radiology and Imaging Sciences Section of Musculoskeletal Imaging, Atlanta, GA (United States); Martinez, Anthony; Edgar, Mark [Emory University Hospital, Department of Pathology, Atlanta, GA (United States); Reimer, Nickolas [Emory University Hospital, Department of Orthopedic Surgery, Atlanta, GA (United States); Subhawong, Ty [University of Miami, Department of Radiology, Miami, FL (United States)

    2018-01-15

    Compile the largest study to date on the imaging and clinical features of the classic spindle cell/pleomorphic lipoma spectrum and suggest this diagnosis be included in the differential for benign and malignant macroscopic fat-containing soft tissue masses regardless of the mass location or patient demographics. An institutional search was performed to identify all available classic-type spindle cell/pleomorphic lipomas with available demographic and imaging data. Images and reports were analyzed by one MSK-trained radiologist and radiographic, anatomic and clinical data were recorded. Additionally, a literature search was performed to identify studies describing the spindle cell lipoma spectrum imaging features and were combined with institutional data. Forty-two institutional cases were identified, 37 of which had MRIs performed among which 21 had images available (T1- and T2-weighted pulse sequences) for review while the remainder had outside reports detailing the mass imaging features. There was a mean age of 57 with 79% of cases occurring in males. Contrary to prior reports, 57% of masses were subcutaneous, and the neck and back region accounted for 26% of cases. When the institutional cases were combined with available data in the literature, there was a new sample size of 91 masses, 74 of which had MRI and/or CT data. Eighty-seven percent of masses were heterogeneous, 51% were composed of less than 75% fat, 65% were in the back, neck or shoulder region, 27% of masses were deep and 91% demonstrated enhancement. Eighty-two percent of patients were males with a mean age of 58 at excision. Imaging features, patient demographics and tumor location alone are not enough to differentiate tumors of the spindle cell lipoma spectrum from other macroscopic fat-containing benign and malignant tumors, and these entities should be included in the same imaging differential diagnosis. (orig.)

  9. Method for combined FDG-PET and radiographic imaging of primary breast cancers.

    Science.gov (United States)

    Adler, Lee P; Weinberg, Irving N; Bradbury, Michelle S; Levine, Edward A; Lesko, Nadine M; Geisinger, Kim R; Berg, Wendie A; Freimanis, Rita I

    2003-01-01

    The purpose of the study was to demonstrate the feasibility of a hybrid functional/anatomic breast imaging platform with biopsy capability for facilitating lesion detection and diagnosis. This platform consists of an investigative dedicated positron emission mammography (PEM) device mounted on a stereotactic X-ray mammography system, permitting sequential acquisition of mammographic and emission images during a single breast compression. There is automatic coregistration of images from both modalities, and these results can be successfully correlated with histopathologic findings. The potential utility of functional images correlated to anatomic images would include noninvasively detecting clinically and radiographically occult cancers, assessing response to therapy, discriminating between benign and malignant breast masses, and ultimately reducing the number of invasive and costly surgical interventions. A spot-digital mammogram and subsequent PEM image, collected over a 4-minute period, were obtained in a single patient with the breast in compression after intravenous injection of (F-18)-2-deoxy-2-fluoro-D-glucose (FDG) at the time of stereotactic biopsy. The authors conclude that FDG-based lesion localization information may be combined with the lesion X-ray attenuation characteristics using this common imaging platform.

  10. A combined learning algorithm for prostate segmentation on 3D CT images.

    Science.gov (United States)

    Ma, Ling; Guo, Rongrong; Zhang, Guoyi; Schuster, David M; Fei, Baowei

    2017-11-01

    Segmentation of the prostate on CT images has many applications in the diagnosis and treatment of prostate cancer. Because of the low soft-tissue contrast on CT images, prostate segmentation is a challenging task. A learning-based segmentation method is proposed for the prostate on three-dimensional (3D) CT images. We combine population-based and patient-based learning methods for segmenting the prostate on CT images. Population data can provide useful information to guide the segmentation processing. Because of inter-patient variations, patient-specific information is particularly useful to improve the segmentation accuracy for an individual patient. In this study, we combine a population learning method and a patient-specific learning method to improve the robustness of prostate segmentation on CT images. We train a population model based on the data from a group of prostate patients. We also train a patient-specific model based on the data of the individual patient and incorporate the information as marked by the user interaction into the segmentation processing. We calculate the similarity between the two models to obtain applicable population and patient-specific knowledge to compute the likelihood of a pixel belonging to the prostate tissue. A new adaptive threshold method is developed to convert the likelihood image into a binary image of the prostate, and thus complete the segmentation of the gland on CT images. The proposed learning-based segmentation algorithm was validated using 3D CT volumes of 92 patients. All of the CT image volumes were manually segmented independently three times by two, clinically experienced radiologists and the manual segmentation results served as the gold standard for evaluation. The experimental results show that the segmentation method achieved a Dice similarity coefficient of 87.18 ± 2.99%, compared to the manual segmentation. By combining the population learning and patient-specific learning methods, the proposed method is

  11. The greenhouse effect gases

    International Nuclear Information System (INIS)

    2006-06-01

    This road-map proposes by the Group Total aims to inform the public on the greenhouse effect gases. It presents the greenhouses effect as a key component of the climate system, the impacts of the human activity, the foreseeable consequences of global warming, the Kyoto protocol and Total commitment in the domain. (A.L.B.)

  12. Clinical combination of multiphoton tomography and high frequency ultrasound imaging for evaluation of skin diseases

    Science.gov (United States)

    König, K.; Speicher, M.; Koehler, M. J.; Scharenberg, R.; Elsner, P.; Kaatz, M.

    2010-02-01

    For the first time, high frequency ultrasound imaging, multiphoton tomography, and dermoscopy were combined in a clinical study. Different dermatoses such as benign and malign skin cancers, connective tissue diseases, inflammatory skin diseases and autoimmune bullous skin diseases have been investigated with (i) state-of-the-art and highly sophisticated ultrasound systems for dermatology, (ii) the femtosecond-laser multiphoton tomograph DermaInspectTM and (iii) dermoscopes. Dermoscopy provides two-dimensional color imaging of the skin surface with a magnification up to 70x. Ultrasound images are generated from reflections of the emitted ultrasound signal, based on inhomogeneities of the tissue. These echoes are converted to electrical signals. Depending on the ultrasound frequency the penetration depth varies from about 1 mm to 16 mm in dermatological application. The 100-MHz-ultrasound system provided an axial resolution down to 16 μm and a lateral resolution down to 32 μm. In contrast to the wide-field ultrasound images, multiphoton tomography provided horizontal optical sections of 0.36×0.36 mm2 down to 200 μm tissue depth with submicron resolution. The autofluorescence of mitochondrial coenzymes, melanin, and elastin as well as the secondharmonic- generation signal of the collagen network were imaged. The combination of ultrasound and multiphoton tomography provides a novel opportunity for diagnostics of skin disorders.

  13. Image Encryption Using Stream Cipher Based on Nonlinear Combination Generator with Enhanced Security

    Directory of Open Access Journals (Sweden)

    Belmeguenaï Aîssa

    2013-03-01

    Full Text Available The images are very largely used in our daily life; the security of their transfer became necessary. In this work a novel image encryption scheme using stream cipher algorithm based on nonlinear combination generator is developed. The main contribution of this work is to enhance the security of encrypted image. The proposed scheme is based on the use the several linear feedback shifts registers whose feedback polynomials are primitive and of degrees are all pairwise coprimes combined by resilient function whose resiliency order, algebraic degree and nonlinearity attain Siegenthaler’s and Sarkar, al.’s bounds. This proposed scheme is simple and highly efficient. In order to evaluate performance, the proposed algorithm was measured through a series of tests. These tests included visual test and histogram analysis, key space analysis, correlation coefficient analysis, image entropy, key sensitivity analysis, noise analysis, Berlekamp-Massey attack, correlation attack and algebraic attack. Experimental results demonstrate the proposed system is highly key sensitive, highly resistance to the noises and shows a good resistance against brute-force, statistical attacks, Berlekamp-Massey attack, correlation attack, algebraic attack and a robust system which makes it a potential candidate for encryption of image.

  14. New mammography screen/film combinations: Imaging characteristics and radiation dose

    Energy Technology Data Exchange (ETDEWEB)

    Kimme-Smith, C.; Bassett, L.W.; Gold, R.H.; Zheutlin, J.; Gornbein, J.A. (Iris Cantor Center for Breast Imaging, CA (USA))

    1990-04-01

    Five types of film (Kodak OM, Kodak OM-SO177, Konica CM, Dupont Microvision, and Fuji MiMa) exposed in combination with seven different intensifying screens (Min R, Min R Medium, Siemens Orthox MA, Kyokka HR Mammo Fine, Agfa Gevaert Detail S (old and new), and Konica Monarch) were processed for either 90 sec (at 33.3{degrees}C) or 3 min (at 35.0 degrees C). The films imaged a Computerized Imaging Reference System phantom with additional detail test objects placed on its surface to produce four groups of objects with which to evaluate resolution and contrast. For objects that tested resolution, the Kyokka HR Mammo Fine (Fuji) screen was statistically significantly superior; for objects that tested contrast, the Konica Monarch screen was statistically significantly superior. Extended processing did not affect Dupont and Kodak OM film as much as it affected the other films. It did affect contrast for the other films tested. The mean glandular doses from gridless exposures ranged from 32 to 80 mrad (0.32-0.80 mGy) over all film/screen/processing combinations for a 4.5-cm-thick test object. Several new film/screen combinations can provide images superior to the Kodak Min R/OM combination at a reduced radiation dose. The Kyokka HR Mammo Fine (Fuji) screen was found statistically superior in radiographic resolution of mammographic test objects and the Konica Monarch screen was found to be superior in defining contrast.

  15. New mammography screen/film combinations: imaging characteristics and radiation dose.

    Science.gov (United States)

    Kimme-Smith, C; Bassett, L W; Gold, R H; Zheutlin, J; Gornbein, J A

    1990-04-01

    Five types of film (Kodak OM, Kodak OM-SO177, Konica CM, Dupont Microvision, and Fuji MiMa) exposed in combination with seven different intensifying screens (Min R, Min R Medium, Siemens Orthox MA, Kyokka HR Mammo Fine, Agfa Gevaert Detail S (old and new), and Konica Monarch) were processed for either 90 sec (at 33.3 degrees C) or 3 min (at 35.0 degrees C). The films imaged a Computerized Imaging Reference System phantom with additional detail test objects placed on its surface to produce four groups of objects with which to evaluate resolution and contrast. For objects that tested resolution, the Kyokka HR Mammo Fine (Fuji) screen was statistically significantly superior; for objects that tested contrast, the Konica Monarch screen was statistically significantly superior. Extended processing did not affect Dupont and Kodak OM film as much as it affected the other films. It did affect contrast for the other films tested. The mean glandular doses from gridless exposures ranged from 32 to 80 mrad (0.32-0.80 mGy) over all film/screen/processing combinations for a 4.5-cm-thick test object. Several new film/screen combinations can provide images superior to the Kodak Min R/OM combination at a reduced radiation dose. The Kyokka HR Mammo Fine (Fuji) screen was found statistically superior in radiographic resolution of mammographic test objects and the Konica Monarch screen was found to be superior in defining contrast.

  16. Automatic plankton image classification combining multiple view features via multiple kernel learning.

    Science.gov (United States)

    Zheng, Haiyong; Wang, Ruchen; Yu, Zhibin; Wang, Nan; Gu, Zhaorui; Zheng, Bing

    2017-12-28

    Plankton, including phytoplankton and zooplankton, are the main source of food for organisms in the ocean and form the base of marine food chain. As the fundamental components of marine ecosystems, plankton is very sensitive to environment changes, and the study of plankton abundance and distribution is crucial, in order to understand environment changes and protect marine ecosystems. This study was carried out to develop an extensive applicable plankton classification system with high accuracy for the increasing number of various imaging devices. Literature shows that most plankton image classification systems were limited to only one specific imaging device and a relatively narrow taxonomic scope. The real practical system for automatic plankton classification is even non-existent and this study is partly to fill this gap. Inspired by the analysis of literature and development of technology, we focused on the requirements of practical application and proposed an automatic system for plankton image classification combining multiple view features via multiple kernel learning (MKL). For one thing, in order to describe the biomorphic characteristics of plankton more completely and comprehensively, we combined general features with robust features, especially by adding features like Inner-Distance Shape Context for morphological representation. For another, we divided all the features into different types from multiple views and feed them to multiple classifiers instead of only one by combining different kernel matrices computed from different types of features optimally via multiple kernel learning. Moreover, we also applied feature selection method to choose the optimal feature subsets from redundant features for satisfying different datasets from different imaging devices. We implemented our proposed classification system on three different datasets across more than 20 categories from phytoplankton to zooplankton. The experimental results validated that our system

  17. Imaging of the central nervous system with combined half-Fourier and rectangular pixel technique

    International Nuclear Information System (INIS)

    Runge, V.M.; Wood, M.L.; Wolf, C.R.; Carollo, B.R.

    1988-01-01

    The diagnostic value of a combined half-Fourier and rectangular pixel technique for T2-weighted imaging of the central nervous system (CNS) was assessed with results obtained in 45 patients. This technique presents a new approach to T2 screening of the CNS. Imaging time is cut by a factor of approximately four, with no compromise in signal-to-noise ratio and spatial resolution equivalent to a 256X128 matrix. Gradient moment nulling is essential in order to minimize flow artifacts. Lesion detection is equivalent to a 256X256 matrix in the worst case, that is, for detection of small punctate abnormalities (multiple sclerosis plaques)

  18. First elemental imaging experiments on a combined PGAI and NT setup at the Budapest Research Reactor

    International Nuclear Information System (INIS)

    Belgya, T.; Kis, Z.; Szentmiklosi, L.; Kasztovszky, Zs.; Materna, T.; Festa, G.; Caroppi, P.A.

    2008-01-01

    The European collaboration 'ANCIENT CHARM' (http://ancient-charm.neutron-eu.net/ach/) aims to develop new non-destructive neutron techniques to image the internal composition of complex archaeological objects in order to answer various archaeological questions. Among these techniques, prompt gamma activation imaging (PGAI) and neutron tomography (NT) form a unique combination which can determine the 3D distribution of most elements in objects with a non-destructive procedure. A spatial resolution better than 2 mm has already been achieved in a moderately scattering matrix material. (author)

  19. Artifact reduction of compressed images and video combining adaptive fuzzy filtering and directional anisotropic diffusion

    DEFF Research Database (Denmark)

    Nadernejad, Ehsan; Forchhammer, Søren; Korhonen, Jari

    2011-01-01

    and ringing artifacts, we have applied directional anisotropic diffusion. Besides that, the selection of the adaptive threshold parameter for the diffusion coefficient has also improved the performance of the algorithm. Experimental results on JPEG compressed images as well as MJPEG and H.264 compressed......Fuzzy filtering is one of the recently developed methods for reducing distortion in compressed images and video. In this paper, we combine the powerful anisotropic diffusion equations with fuzzy filtering in order to reduce the impact of artifacts. Based on the directional nature of the blocking...

  20. A New Image Encryption Technique Combining Hill Cipher Method, Morse Code and Least Significant Bit Algorithm

    Science.gov (United States)

    Nofriansyah, Dicky; Defit, Sarjon; Nurcahyo, Gunadi W.; Ganefri, G.; Ridwan, R.; Saleh Ahmar, Ansari; Rahim, Robbi

    2018-01-01

    Cybercrime is one of the most serious threats. Efforts are made to reduce the number of cybercrime is to find new techniques in securing data such as Cryptography, Steganography and Watermarking combination. Cryptography and Steganography is a growing data security science. A combination of Cryptography and Steganography is one effort to improve data integrity. New techniques are used by combining several algorithms, one of which is the incorporation of hill cipher method and Morse code. Morse code is one of the communication codes used in the Scouting field. This code consists of dots and lines. This is a new modern and classic concept to maintain data integrity. The result of the combination of these three methods is expected to generate new algorithms to improve the security of the data, especially images.

  1. AN AUTOMATIC PROCEDURE FOR COMBINING DIGITAL IMAGES AND LASER SCANNER DATA

    Directory of Open Access Journals (Sweden)

    W. Moussa

    2012-07-01

    Full Text Available Besides improving both the geometry and the visual quality of the model, the integration of close-range photogrammetry and terrestrial laser scanning techniques directs at filling gaps in laser scanner point clouds to avoid modeling errors, reconstructing more details in higher resolution and recovering simple structures with less geometric details. Thus, within this paper a flexible approach for the automatic combination of digital images and laser scanner data is presented. Our approach comprises two methods for data fusion. The first method starts by a marker-free registration of digital images based on a point-based environment model (PEM of a scene which stores the 3D laser scanner point clouds associated with intensity and RGB values. The PEM allows the extraction of accurate control information for the direct computation of absolute camera orientations with redundant information by means of accurate space resection methods. In order to use the computed relations between the digital images and the laser scanner data, an extended Helmert (seven-parameter transformation is introduced and its parameters are estimated. Precedent to that, in the second method, the local relative orientation parameters of the camera images are calculated by means of an optimized Structure and Motion (SaM reconstruction method. Then, using the determined transformation parameters results in having absolute oriented images in relation to the laser scanner data. With the resulting absolute orientations we have employed robust dense image reconstruction algorithms to create oriented dense image point clouds, which are automatically combined with the laser scanner data to form a complete detailed representation of a scene. Examples of different data sets are shown and experimental results demonstrate the effectiveness of the presented procedures.

  2. Noble gases as cardioprotectants - translatability and mechanism

    NARCIS (Netherlands)

    Smit, Kirsten F.; Weber, Nina C.; Hollmann, Markus W.; Preckel, Benedikt

    2015-01-01

    Several noble gases, although classified as inert substances, exert a tissue-protective effect in different experimental models when applied before organ ischaemia as an early or late preconditioning stimulus, after ischaemia as a post-conditioning stimulus or when given in combination before,

  3. CADMIUM II: combining image processing and symbolic reasoning for computer-aided diagnosis

    Science.gov (United States)

    Taylor, Paul; Alberdi, Eugenio; Lee, Richard; Fox, John; Sordo, Margarita; Todd-Pokropek, Andrew

    2000-06-01

    This paper describes a prototype computer aided diagnosis system to assist in the interpretation of mammograms. The distinctive feature of our work is the combination of image processing and decision support. We wish, in our system, to relate the data in a digital image to a decision contained in a clinical guideline describing a patient's management. Our system is designed to present a user with sets of arguments for each of the possible interpretations of a feature detected on the image and for each of the possible management options that might be followed in handling the patient's care. We have carried out an extensive knowledge elicitation exercise, involving the analysis of 'think out loud' protocols obtained from expert radiologists interpreting mammograms form a carefully selected test set. The results of this analysis reveal which terms capture the most salient characteristics of calcifications. These terms will be used to construct the arguments used in the decision support provided by CADMIUM II. The final element of CADMIUM II is a library of image processing algorithms. A set of different approaches to the detection and characterization of calcifications has been implemented. The image processing is used to provide a quantitative estimate of the evidence that an image contains in support of an argument.

  4. A Variational Level Set Model Combined with FCMS for Image Clustering Segmentation

    Directory of Open Access Journals (Sweden)

    Liming Tang

    2014-01-01

    Full Text Available The fuzzy C means clustering algorithm with spatial constraint (FCMS is effective for image segmentation. However, it lacks essential smoothing constraints to the cluster boundaries and enough robustness to the noise. Samson et al. proposed a variational level set model for image clustering segmentation, which can get the smooth cluster boundaries and closed cluster regions due to the use of level set scheme. However it is very sensitive to the noise since it is actually a hard C means clustering model. In this paper, based on Samson’s work, we propose a new variational level set model combined with FCMS for image clustering segmentation. Compared with FCMS clustering, the proposed model can get smooth cluster boundaries and closed cluster regions due to the use of level set scheme. In addition, a block-based energy is incorporated into the energy functional, which enables the proposed model to be more robust to the noise than FCMS clustering and Samson’s model. Some experiments on the synthetic and real images are performed to assess the performance of the proposed model. Compared with some classical image segmentation models, the proposed model has a better performance for the images contaminated by different noise levels.

  5. Combining nonlinear multiresolution system and vector quantization for still image compression

    Energy Technology Data Exchange (ETDEWEB)

    Wong, Y.

    1993-12-17

    It is popular to use multiresolution systems for image coding and compression. However, general-purpose techniques such as filter banks and wavelets are linear. While these systems are rigorous, nonlinear features in the signals cannot be utilized in a single entity for compression. Linear filters are known to blur the edges. Thus, the low-resolution images are typically blurred, carrying little information. We propose and demonstrate that edge-preserving filters such as median filters can be used in generating a multiresolution system using the Laplacian pyramid. The signals in the detail images are small and localized to the edge areas. Principal component vector quantization (PCVQ) is used to encode the detail images. PCVQ is a tree-structured VQ which allows fast codebook design and encoding/decoding. In encoding, the quantization error at each level is fed back through the pyramid to the previous level so that ultimately all the error is confined to the first level. With simple coding methods, we demonstrate that images with PSNR 33 dB can be obtained at 0.66 bpp without the use of entropy coding. When the rate is decreased to 0.25 bpp, the PSNR of 30 dB can still be achieved. Combined with an earlier result, our work demonstrate that nonlinear filters can be used for multiresolution systems and image coding.

  6. On combining spectral and spatial information of hyperspectral image for camouflaged target detecting

    Science.gov (United States)

    Hua, Wenshen; Liu, Xun; Yang, Jia

    2013-12-01

    Detecting enemy's targets and being undetectable play increasingly important roles in modern warfare. Hyperspectral images can provide large spectral range and high spectral resolution, which are invaluable in discriminating between camouflaged targets and backgrounds. As supervised classification requires prior knowledge which cannot be acquired easily, unsupervised classification usually is adopted to process hyperspectral images to detect camouflaged target. But one of its drawbacks—low detecting accuracy confines its application for camouflaged target detecting. Most research on the processing of hyperspectral image tends to focus exclusively on spectral domain and ignores spatial domain. However current hyperspectral image provides high spatial resolution which contains useful information for camouflaged target detecting. A new method combining spectral and spatial information is proposed to increase the detecting accuracy using unsupervised classification. The method has two steps. In the first step, a traditional unsupervised classifier (i.e. K-MEANS, ISODATA) is adopted to classify the hyperspectral image to acquire basic classifications or clusters. During the second step, a 3×3 model and spectral angle mapping are utilized to test the spatial character of the hyperspectral image. The spatial character is defined as spatial homogeneity and calculated by spectral angle mapping. Theory analysis and experiment shows the method is reasonable and efficient. Camouflaged targets are extracted from the background and different camouflaged targets are also recognized. And the proposed algorithm outperforms K-MEANS in terms of detecting accuracy, robustness and edge's distinction. This paper demonstrates the new method is meaningful to camouflaged targets detecting.

  7. A one-time pad encryption method combining full-phase image encryption and hiding

    Science.gov (United States)

    Li, Jiaosheng; Xiong, Jiaxiang; Zhang, Qinnan; Zhong, Liyun; Zhou, Yunfei; Li, Jun; Lu, Xiaoxu

    2017-08-01

    A one-time pad encryption method combining full-phase image encryption and hiding is proposed. Firstly, original images are encoded in the phase and encrypted by phase keys loaded on the phase-only liquid crystal spatial light modulator, where the phase keys can be distributed using a quantum key distribution method. Subsequently, a host image is introduced to produce a reference wave, and overlap with an object wave to form an interferogram. Finally, based on phase-shifting interferometry, we can achieve the above encrypted image hiding. Both the simulation and experiment research demonstrate the feasibility of the proposed method, meanwhile the key and the encrypted image can be changed randomly, so the proposed system reveals the high flexibility, anti-attack ability and can be used to implement the one-time pad to achieve absolute secure transmission with the quantum key distribution method. Moreover, system security will be improved due to the fact that encryption information hidden in the host image can be treated as background noise, which does not attract the attention of the attacker.

  8. Combination of widefield fluorescence imaging and nonlinear optical microscopy of oral epithelial neoplasia

    Science.gov (United States)

    Pal, Rahul; Edward, Kert; Brown, Tyra; Ma, Liang; Yang, Jinping; McCammon, Susan; Motamedi, Massoud; Vargas, Gracie

    2013-03-01

    Multiphoton Autofluorescence Microscopy (MPAM) and Second Harmonic Generation Microscopy (SHGM) have shown the potential for noninvasive assessment of oral precancers and cancers. We have explored a combination of these nonlinear optical microscopic imaging techniques with widefield fluorescence imaging to assess morphometry similar to that of pathologic evaluation as well as information from endogenous fluorophores, which are altered with neoplastic transformation. Widefield fluorescence revealed areas of interest corresponding to sites with precancers or early tumors, generally resulting in a decrease in green emission or increase in red emission. Subsequent microscopy revealed significant differences in morphology between normal, dysplastic/neoplastic mucosa for all layers. Combination of a widefield and a microscopic technique provides a novel approach for tissue morphometric analysis along with large area assessment of tissue autofluorescence properties.

  9. Gemella morbillorum deep brain abscess successfully treated with combined stereotactic, medical, and imaging approach

    Energy Technology Data Exchange (ETDEWEB)

    Messori, Anna; Bartolucci, Francesca; Dini, Marco; Paggi, Alessandra Mataloni; Ricciuti, Riccardo A.; Rychlicki, Franco; Salvolini, Ugo E-mail: u.salvolini@popcsi.unian.it

    2002-11-01

    A rare case of brain abscess due to Gemella morbillorum, a normal inhabitant of the oral cavity, is presented. The aim of this report is to draw the attention of radiology literature readers to this little known pathogen, which caused a potentially life-threatening condition in an immunocompetent young man, and to emphasise the usefulness of a combined stereotactic, medical, and imaging approach to deep-located brain abscesses.

  10. Gemella morbillorum deep brain abscess successfully treated with combined stereotactic, medical, and imaging approach

    International Nuclear Information System (INIS)

    Messori, Anna; Bartolucci, Francesca; Dini, Marco; Paggi, Alessandra Mataloni; Ricciuti, Riccardo A.; Rychlicki, Franco; Salvolini, Ugo

    2002-01-01

    A rare case of brain abscess due to Gemella morbillorum, a normal inhabitant of the oral cavity, is presented. The aim of this report is to draw the attention of radiology literature readers to this little known pathogen, which caused a potentially life-threatening condition in an immunocompetent young man, and to emphasise the usefulness of a combined stereotactic, medical, and imaging approach to deep-located brain abscesses

  11. Combining angular differential imaging and accurate polarimetry with SPHERE/IRDIS to characterize young giant exoplanets

    Science.gov (United States)

    van Holstein, Rob G.; Snik, Frans; Girard, Julien H.; de Boer, Jozua; Ginski, C.; Keller, Christoph U.; Stam, Daphne M.; Beuzit, Jean-Luc; Mouillet, David; Kasper, Markus; Langlois, Maud; Zurlo, Alice; de Kok, Remco J.; Vigan, Arthur

    2017-09-01

    Young giant exoplanets emit infrared radiation that can be linearly polarized up to several percent. This linear polarization can trace: 1) the presence of atmospheric cloud and haze layers, 2) spatial structure, e.g. cloud bands and rotational flattening, 3) the spin axis orientation and 4) particle sizes and cloud top pressure. We introduce a novel high-contrast imaging scheme that combines angular differential imaging (ADI) and accurate near-infrared polarimetry to characterize self-luminous giant exoplanets. We implemented this technique at VLT/SPHEREIRDIS and developed the corresponding observing strategies, the polarization calibration and the data-reduction approaches. The combination of ADI and polarimetry is challenging, because the field rotation required for ADI negatively affects the polarimetric performance. By combining ADI and polarimetry we can characterize planets that can be directly imaged with a very high signal-to-noise ratio. We use the IRDIS pupil-tracking mode and combine ADI and principal component analysis to reduce speckle noise. We take advantage of IRDIS' dual-beam polarimetric mode to eliminate differential effects that severely limit the polarimetric sensitivity (flat-fielding errors, differential aberrations and seeing), and thus further suppress speckle noise. To correct for instrumental polarization effects, we apply a detailed Mueller matrix model that describes the telescope and instrument and that has an absolute polarimetric accuracy analysis. We estimate preliminary 1σ upper limits on the degree of linear polarization of ˜ 1% and ˜ 0.1% for the planets of HR 8799 and PZ Tel B, respectively. The achieved sub-percent sensitivity and accuracy show that our technique has great promise for characterizing exoplanets through direct-imaging polarimetry

  12. The Values of Combined and Sub-Stratified Imaging Scores with Ultrasonography and Mammography in Breast Cancer Subtypes.

    Directory of Open Access Journals (Sweden)

    Tsun-Hou Chang

    Full Text Available The Breast Imaging Reporting and Data System (BI-RADS of Mammography (MG and Ultrasonography (US were equivalent to the "5-point score" and applied for combined and sub-stratified imaging assessments. This study evaluated the value of combined and sub-stratified imaging assessments with MG and US over breast cancer subtypes (BCS.Medical records of 5,037 cases having imaging-guided core biopsy, performed from 2009 to 2012, were retrospectively reviewed. This study selected 1,995 cases (1,457 benign and 538 invasive cancer having both MG and US before biopsy. These cases were categorized with the "5-point score" for their MG and US, and applied for combined and sub-stratified imaging assessments. Invasive cancers were classified on the basis of BCS, and correlated with combined and sub-stratified imaging assessments.These selected cases were evaluated by the "5-point score." MG, US, and combined and sub-stratified imaging assessments all revealed statistically significant (P < 0.001 incidence of malignancy. The sensitivity was increased in the combined imaging score (99.8%, and the specificity was increased in the sub-stratified combined score (75.4%. In the sub-stratified combined imaging assessment, all BCS can be classified with higher scores (abnormality hierarchy, and luminal B subtype showed the most salient result (hierarchy: higher, 95%; lower, 5%.Combined and sub-stratified imaging assessments can increase sensitivity and specificity of breast cancer diagnosis, respectively, and Luminal B subtype shows the best identification by sub-stratified combined imaging scoring.

  13. Combined DaT imaging and olfactory testing for differentiating parkinsonian disorders

    DEFF Research Database (Denmark)

    Borghammer, P.; Knudsen, K.; Østergaard, K.

    2014-01-01

    disorders (aPD). However, most iPD/DLB patients are hyposmic, whereas the majority of aPD patients were reported to have intact olfaction. For this reason, we conducted a longitudinal follow-up study to investigate the power of combined DaT imaging and olfactory testing to predict the final diagnosis......ObjectiveDopamine transporter (DaT) imaging with single photon emission computed tomography (SPECT) detects loss of striatal dopaminergic innervation with very high sensitivity. It cannot readily distinguish idiopathic Parkinson's disease (iPD) and dementia with Lewy bodies (DLB) from atypical...... of the patients. Materials and methodsA total of 129 patients received [123I]FP-CIT SPECT and olfactory testing at baseline assessment. Clinical follow-up 3012months later was the diagnostic standard of truth. A normative dataset of 24 healthy controls was used for comparison. ResultsBaseline DaT imaging...

  14. A Novel Multivoxel-Based Quantitation of Metabolites and Lipids Noninvasively Combined with Diffusion-Weighted Imaging in Breast Cancer

    Science.gov (United States)

    2012-09-01

    invasive lobular cancer), twenty patients with benign breast tumor ( fibroadenoma , proliferative fibrocystic change and papillomas) will be...Metabolites and Lipids Noninvasively Combined with Diffusion-Weighted Imaging in Breast Cancer PRINCIPAL INVESTIGATOR: Michael Albert Thomas...5a. CONTRACT NUMBER Noninvasively Combined with Diffusion-Weighted Imaging in Breast Cancer 5b. GRANT NUMBER W81XWH-10-1-0743 5c. PROGRAM

  15. A study on quantifying COPD severity by combining pulmonary function tests and CT image analysis

    Science.gov (United States)

    Nimura, Yukitaka; Kitasaka, Takayuki; Honma, Hirotoshi; Takabatake, Hirotsugu; Mori, Masaki; Natori, Hiroshi; Mori, Kensaku

    2011-03-01

    This paper describes a novel method that can evaluate chronic obstructive pulmonary disease (COPD) severity by combining measurements of pulmonary function tests and measurements obtained from CT image analysis. There is no cure for COPD. However, with regular medical care and consistent patient compliance with treatments and lifestyle changes, the symptoms of COPD can be minimized and progression of the disease can be slowed. Therefore, many diagnosis methods based on CT image analysis have been proposed for quantifying COPD. Most of diagnosis methods for COPD extract the lesions as low-attenuation areas (LAA) by thresholding and evaluate the COPD severity by calculating the LAA in the lung (LAA%). However, COPD is usually the result of a combination of two conditions, emphysema and chronic obstructive bronchitis. Therefore, the previous methods based on only LAA% do not work well. The proposed method utilizes both of information including the measurements of pulmonary function tests and the results of the chest CT image analysis to evaluate the COPD severity. In this paper, we utilize a multi-class AdaBoost to combine both of information and classify the COPD severity into five stages automatically. The experimental results revealed that the accuracy rate of the proposed method was 88.9% (resubstitution scheme) and 64.4% (leave-one-out scheme).

  16. COMBINED ANALYSIS OF IMAGES AND SPECTRAL ENERGY DISTRIBUTIONS OF TAURUS PROTOSTARS

    International Nuclear Information System (INIS)

    Gramajo, Luciana V.; Gomez, Mercedes; Whitney, Barbara A.; Robitaille, Thomas P.

    2010-01-01

    We present an analysis of spectral energy distributions (SEDs), near- and mid-infrared images, and Spitzer spectra of eight embedded Class I/II objects in the Taurus-Auriga molecular cloud. The initial model for each source was chosen using the grid of young stellar objects (YSOs) and SED fitting tool of Robitaille et al. Then the models were refined using the radiative transfer code of Whitney et al. to fit both the spectra and the infrared images of these objects. In general, our models agree with previous published analyses. However, our combined models should provide more reliable determinations of the physical and geometrical parameters since they are derived from SEDs, including the Spitzer spectra, covering the complete spectral range; and high-resolution near-infrared and Spitzer IRAC images. The combination of SED and image modeling better constrains the different components (central source, disk, envelope) of the YSOs. Our derived luminosities are higher, on average, than previous estimates because we account for the viewing angles (usually nearly edge-on) of most of the sources. Our analysis suggests that the standard rotating collapsing protostar model with disks and bipolar cavities works well for the analyzed sample of objects in the Taurus molecular cloud.

  17. Improved medical image modality classification using a combination of visual and textual features.

    Science.gov (United States)

    Dimitrovski, Ivica; Kocev, Dragi; Kitanovski, Ivan; Loskovska, Suzana; Džeroski, Sašo

    2015-01-01

    In this paper, we present the approach that we applied to the medical modality classification tasks at the ImageCLEF evaluation forum. More specifically, we used the modality classification databases from the ImageCLEF competitions in 2011, 2012 and 2013, described by four visual and one textual types of features, and combinations thereof. We used local binary patterns, color and edge directivity descriptors, fuzzy color and texture histogram and scale-invariant feature transform (and its variant opponentSIFT) as visual features and the standard bag-of-words textual representation coupled with TF-IDF weighting. The results from the extensive experimental evaluation identify the SIFT and opponentSIFT features as the best performing features for modality classification. Next, the low-level fusion of the visual features improves the predictive performance of the classifiers. This is because the different features are able to capture different aspects of an image, their combination offering a more complete representation of the visual content in an image. Moreover, adding textual features further increases the predictive performance. Finally, the results obtained with our approach are the best results reported on these databases so far. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Hybrid Microscopy: Enabling Inexpensive High-Performance Imaging through Combined Physical and Optical Magnifications.

    Science.gov (United States)

    Zhang, Yu Shrike; Chang, Jae-Byum; Alvarez, Mario Moisés; Trujillo-de Santiago, Grissel; Aleman, Julio; Batzaya, Byambaa; Krishnadoss, Vaishali; Ramanujam, Aishwarya Aravamudhan; Kazemzadeh-Narbat, Mehdi; Chen, Fei; Tillberg, Paul W; Dokmeci, Mehmet Remzi; Boyden, Edward S; Khademhosseini, Ali

    2016-03-15

    To date, much effort has been expended on making high-performance microscopes through better instrumentation. Recently, it was discovered that physical magnification of specimens was possible, through a technique called expansion microscopy (ExM), raising the question of whether physical magnification, coupled to inexpensive optics, could together match the performance of high-end optical equipment, at a tiny fraction of the price. Here we show that such "hybrid microscopy" methods--combining physical and optical magnifications--can indeed achieve high performance at low cost. By physically magnifying objects, then imaging them on cheap miniature fluorescence microscopes ("mini-microscopes"), it is possible to image at a resolution comparable to that previously attainable only with benchtop microscopes that present costs orders of magnitude higher. We believe that this unprecedented hybrid technology that combines expansion microscopy, based on physical magnification, and mini-microscopy, relying on conventional optics--a process we refer to as Expansion Mini-Microscopy (ExMM)--is a highly promising alternative method for performing cost-effective, high-resolution imaging of biological samples. With further advancement of the technology, we believe that ExMM will find widespread applications for high-resolution imaging particularly in research and healthcare scenarios in undeveloped countries or remote places.

  19. BUILDING CHANGE DETECTION BY COMBINING LiDAR DATA AND ORTHO IMAGE

    Directory of Open Access Journals (Sweden)

    D. Peng

    2016-06-01

    Full Text Available The elevation information is not considered in the traditional building change detection methods. This paper presents an algorithm of combining LiDAR data and ortho image for 3D building change detection. The advantages of the proposed approach lie in the fusion of the height and spectral information by thematic segmentation. Furthermore, the proposed method also combines the advantages of pixel-level and object-level change detection by image differencing and object analysis. Firstly, two periods of LiDAR data are filtered and interpolated to generate their corresponding DSMs. Secondly, a binary image of the changed areas is generated by means of differencing and filtering the two DSMs, and then thematic layer is generated and projected onto the DSMs and DOMs. Thirdly, geometric and spectral features of the changed area are calculated, which is followed by decision tree classification for the purpose of extracting the changed building areas. Finally, the statistics of the elevation and area change information as well as the change type of the changed buildings are done for building change analysis. Experimental results show that the completeness and correctness of building change detection are close to 81.8% and 85.7% respectively when the building area is larger than 80 m2, which are increased about 10% when compared with using ortho image alone.

  20. Process of radioactive waste gases

    International Nuclear Information System (INIS)

    Queiser, H.; Schwarz, H.; Schroter, H.J.

    1975-01-01

    A method is described in which the radiation level of waste gases from nuclear power plants containing both activation and fission gases is controlled at or below limits permitted by applicable standards by passing such gases, prior to release to the atmosphere, through an adsorptive delay path including a body of activated carbon having the relation to the throughput and character of such gases. (U.S.)

  1. Sudden releases of gases

    Directory of Open Access Journals (Sweden)

    Chaloupecká Hana

    2014-03-01

    Full Text Available Conurbations all over the world have enlarged for numberless years. The accidental or intentional releases of gases become more frequent. Therefore, these crises situations have to be studied. The aim of this paper is to describe experiments examining these processes that were carried out in the laboratory of Environmental Aerodynamics of the Institute of Thermomechanics AS CR in Nový Knín. Results show huge puff variability from replica to replica.

  2. Combination of cross-sectional and molecular imaging studies in the localization of gastroenteropancreatic neuroendocrine tumors.

    Science.gov (United States)

    Toumpanakis, Christos; Kim, Michelle K; Rinke, Anja; Bergestuen, Deidi S; Thirlwell, Christina; Khan, Mohid S; Salazar, Ramon; Oberg, Kjell

    2014-01-01

    aggressive disease course. When a secondary malignancy has already been established or is strongly suspected, combining molecular imaging techniques (e.g. (18)F-FDG PET and (68)Ga-DOTA PET) takes advantage of the diverse avidities of different tumor types to differentiate lesions of different origins. All the above-mentioned molecular imaging studies should always be reviewed and interpreted in a multidisciplinary (tumor board) meeting in combination with the conventional cross-sectional imaging, as the latter remains the imaging of choice for the evaluation of treatment response and disease follow-up. © 2014 S. Karger AG, Basel

  3. Enhancement of soft X-ray emission from fs laser plasma by using mixture of molecule and atomic gases as cluster jet targets and its application for nanostructure imaging

    Energy Technology Data Exchange (ETDEWEB)

    Pikuz, T A; Faenov, A Ya; Fukuda, Y; Kando, M; Kotaki, H; Daito, I; Homma, T; Kawase, K; Kameshima, T; Kawachi, T; Bolton, P; Daido, H; Kimura, T; Tajima, T; Kato, Y; Bulanov, S V [Kansai Photon Science Institute (KPSI), Japan Atomic Energy Agency (JAEA), Kizugawa-city, Kyoto 619-0215 (Japan); Skobelev, I Yu; Gasilov, S V [Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow (Russian Federation); Boldarev, A S; Gasilov, V A, E-mail: faenov.anatoly@jaea.go.j [Institute for Mathematical Modelling, Russian Academy of Sciences, Moscow (Russian Federation)

    2009-04-01

    Submicron scale clusters, produced by mixture of molecular (CO{sub 2}) and atomic (He) gases expanding from the specifically designed super-sonic nozzle, have been irradiated by femtosecond laser pulses in order to build up a bright debris-free soft X-ray source. Spectroscopy measurements showed that X-ray flux in the strongest oxygen spectral lines (He{sub b}eta at 665.7 eV and L{sub ya}lpha at 653.7 eV) produced by the plasma from gas mixture clusters is 2-8 times larger than in the case of using pure CO{sub 2} or N{sub 2}O clusters as targets and reaches values about 2.8x10{sup 10} ph/(sr centre dot pulse). Lines intensity and spatial dimension were measured from two observation point - along and perpendicular to the laser beam propagation directions. Images of 100 nm thick Mo foils in a wide field of view (cm{sup 2} scale) with high spatial resolution (700 nm) were obtained using LiF crystals as soft X-ray imaging detectors. Agreement between calculated and measured intensity of the image fragment which illustrates overlapping of Mo foil layers confirms accuracy of the plasma parameters measurements.

  4. Fuel gases in Algeria

    International Nuclear Information System (INIS)

    Arachiche, B.; Elandaloussi, H.

    1996-01-01

    For a country like Algeria, fuel gases represent an important economical challenge. To answer the increasing energy demand in the transportation sector, the use of fuel gases allows to preserve the petroleum reserves and to create specific industrial structures devoted to LPG-f (liquefied petroleum gas-fuel) and NGV (natural gas for vehicles). This paper presents the energy policy of Algeria, its reserves, production, and exportations of hydrocarbons and the internal rational use of energy sources according to its economic and environmental policy and to its internal needs. The energy consumption of Algeria in the transportation sector represents 2/3 of the petroleum products consumed in the internal market and follows a rapid increase necessary to the socio-economic development of the country. The Algerian experience in fuel gases is analysed according to the results of two successive experimentation periods for the development of NGV before and after 1994, and the resulting transportation and distribution network is described. The development of LPG-f has followed also an experimental phase for the preparation of regulation texts and a first statement of the vehicles conversion to LPG-f is drawn with its perspectives of development according to future market and prices evolutions. (J.S.)

  5. Control of Self Burning in Coal, Piles by Detection of the generated gases; Control de autoencendidos en Parvas de Carbon por Deteccion de los Gases Producidos

    Energy Technology Data Exchange (ETDEWEB)

    1999-09-01

    The purpose of this Research Project is to find the most appropriate method for immediate and remote detection of the phenomena that take place in Thermic Power Plant coal piles, due to the piling up of great quantities of this fuel and its large surface area. These phenomena are: Slow self-oxidation of the coal, producing loss of its calorific power, with its consequent financial loss. Self-combustion of the coal caused when the gases produced by self-oxidation and temperature conditions combine, and they reach a critical point (that of ignition). One of the most recent and novel methods for detection is the Formation of images of Gases, based on the use of laser turned into the vibration wavelengths of the molecules in the gases. This technique, coupled with Thermography, would give as a spatial map of thus distribution and temperatures of gave. It is necessary, in order to extend the use of this equipment to Thermic Power Plant coal piles, to accurately determine which different gases are emanated as well as the minimum concentration of each one of these and the temperature distribution in space. (Author)

  6. Combining STEREO SECCHI COR2 and HI1 images for automatic CME front edge tracking

    Directory of Open Access Journals (Sweden)

    Kirnosov Vladimir

    2016-01-01

    Full Text Available COR2 coronagraph images are the most commonly used data for coronal mass ejection (CME analysis among the various types of data provided by the STEREO (Solar Terrestrial Relations Observatory SECCHI (Sun-Earth Connection Coronal and Heliospheric Investigation suite of instruments. The field of view (FOV in COR2 images covers 2–15 solar radii (Rs that allow for tracking the front edge of a CME in its initial stage to forecast the lead-time of a CME and its chances of reaching the Earth. However, estimating the lead-time of a CME using COR2 images gives a larger lead-time, which may be associated with greater uncertainty. To reduce this uncertainty, CME front edge tracking should be continued beyond the FOV of COR2 images. Therefore, heliospheric imager (HI1 data that covers 15–90 Rs FOV must be included. In this paper, we propose a novel automatic method that takes both COR2 and HI1 images into account and combine the results to track the front edges of a CME continuously. The method consists of two modules: pre-processing and tracking. The pre-processing module produces a set of segmented images, which contain the signature of a CME, for both COR2 and HI1 separately. In addition, the HI1 images are resized and padded, so that the center of the Sun is the central coordinate of the resized HI1 images. The resulting COR2 and HI1 image set is then fed into the tracking module to estimate the position angle (PA and track the front edge of a CME. The detected front edge is then used to produce a height-time profile that is used to estimate the speed of a CME. The method was validated using 15 CME events observed in the period from January 1, 2008 to August 31, 2009. The results demonstrate that the proposed method is effective for CME front edge tracking in both COR2 and HI1 images. Using this method, the CME front edge can now be tracked automatically and continuously in a much larger range, i.e., from 2 to 90 Rs, for the first time. These

  7. Combining transverse field detectors and color filter arrays to improve multispectral imaging systems.

    Science.gov (United States)

    Martínez, Miguel A; Valero, Eva M; Hernández-Andrés, Javier; Romero, Javier; Langfelder, Giacomo

    2014-05-01

    This work focuses on the improvement of a multispectral imaging sensor based on transverse field detectors (TFDs). We aimed to achieve a higher color and spectral accuracy in the estimation of spectral reflectances from sensor responses. Such an improvement was done by combining these recently developed silicon-based sensors with color filter arrays (CFAs). Consequently, we sacrificed the filter-less full spatial resolution property of TFDs to narrow down the spectrally broad sensitivities of these sensors. We designed and performed several experiments to test the influence of different design features on the estimation quality (type of sensor, tunability, interleaved polarization, use of CFAs, type of CFAs, number of shots), some of which are exclusive to TFDs. We compared systems that use a TFD with systems that use normal monochrome sensors, both combined with multispectral CFAs as well as common RGB filters present in commercial digital color cameras. Results showed that a system that combines TFDs and CFAs performs better than systems with the same type of multispectral CFA and other sensors, or even the same TFDs combined with different kinds of filters used in common imaging systems. We propose CFA+TFD-based systems with one or two shots, depending on the possibility of using longer capturing times or not. Improved TFD systems thus emerge as an interesting possibility for multispectral acquisition, which overcomes the limited accuracy found in previous studies.

  8. Bose-Einstein condensation of atomic gases

    International Nuclear Information System (INIS)

    Anglin, J. R.; Ketterle, W.

    2003-01-01

    The early experiments on Bose-Einstein condensation in dilute atomic gases accomplished three longstanding goals. First, cooling of neutral atoms into their motional state, thus subjecting them to ultimate control, limited only by Heisenberg uncertainty relation. Second, creation of a coherent sample of atoms, in which all occupy the same quantum states, and the realization of atom lasers - devices that output coherent matter waves. And third, creation of gaseous quantum fluid, with properties that are different from the quantum liquids helium-3 and helium-4. The field of Bose-Einstein condensation of atomic gases has continued to progress rapidly, driven by the combination of new experimental techniques and theoretical advances. The family of quantum degenerate gases has grown, and now includes metastable and fermionic atoms. condensates have become an ultralow-temperature laboratory for atom optics, collisional physics and many-body physics, encompassing phonons, superfluidity, quantized vortices, Josephson junctions and quantum phase transitions. (author)

  9. Development of a combined microSPECT/CT system for small animal imaging

    Science.gov (United States)

    Sun, Mingshan

    Modern advances in the biomedical sciences have placed increased attention on small animals such as mice and rats as models of human biology and disease in biological research and pharmaceutical development. Their small size and fast breeding rate, their physiologic similarity to human, and, more importantly, the availability of sophisticated genetic manipulations, all have made mice and rats the laboratory mammals of choice in these experimental studies. However, the increased use of small animals in biomedical research also calls for new instruments that can measure the anatomic and metabolic information noninvasively with adequate spatial resolution and measurement sensitivity to facilitate these studies. This dissertation describes the engineering development of a combined single photon emission computed tomography (SPECT) and X-ray computed tomography (CT) system dedicated for small animals imaging. The system aims to obtain both the anatomic and metabolic images with submillimeter spatial resolution in a way that the data can be correlated to provide improved image quality and to offer more complete biological evaluation for biomedical studies involving small animals. The project requires development of complete microSPECT and microCT subsystems. Both subsystems are configured with a shared gantry and animal bed with integrated instrumentation for data acquisition and system control. The microCT employs a microfocus X-ray tube and a CCD-based detector for low noise, high resolution imaging. The microSPECT utilizes three semiconductor detectors coupled with pinhole collimators. A significant contribution of this dissertation project is the development of iterative algorithms with geometrical compensation that allows radionuclide images to be reconstructed at submillimeter spatial resolution, but with significantly higher detection efficiency than conventional methods. Both subsystems are capable of helical scans, offering lengthened field of view and improved

  10. Combined kV and MV imaging for real-time tracking of implanted fiducial markers

    International Nuclear Information System (INIS)

    Wiersma, R. D.; Mao Weihua; Xing, L.

    2008-01-01

    In the presence of intrafraction organ motion, target localization uncertainty can greatly hamper the advantage of highly conformal dose techniques such as intensity modulated radiation therapy (IMRT). To minimize the adverse dosimetric effect caused by tumor motion, a real-time knowledge of the tumor position is required throughout the beam delivery process. The recent integration of onboard kV diagnostic imaging together with MV electronic portal imaging devices on linear accelerators can allow for real-time three-dimensional (3D) tumor position monitoring during a treatment delivery. The aim of this study is to demonstrate a near real-time 3D internal fiducial tracking system based on the combined use of kV and MV imaging. A commercially available radiotherapy system equipped with both kV and MV imaging systems was used in this work. A hardware video frame grabber was used to capture both kV and MV video streams simultaneously through independent video channels at 30 frames per second. The fiducial locations were extracted from the kV and MV images using a software tool. The geometric tracking capabilities of the system were evaluated using a pelvic phantom with embedded fiducials placed on a moveable stage. The maximum tracking speed of the kV/MV system is approximately 9 Hz, which is primarily limited by the frame rate of the MV imager. The geometric accuracy of the system is found to be on the order of less than 1 mm in all three spatial dimensions. The technique requires minimal hardware modification and is potentially useful for image-guided radiation therapy systems

  11. FAST OCCLUSION AND SHADOW DETECTION FOR HIGH RESOLUTION REMOTE SENSING IMAGE COMBINED WITH LIDAR POINT CLOUD

    Directory of Open Access Journals (Sweden)

    X. Hu

    2012-08-01

    Full Text Available The orthophoto is an important component of GIS database and has been applied in many fields. But occlusion and shadow causes the loss of feature information which has a great effect on the quality of images. One of the critical steps in true orthophoto generation is the detection of occlusion and shadow. Nowadays LiDAR can obtain the digital surface model (DSM directly. Combined with this technology, image occlusion and shadow can be detected automatically. In this paper, the Z-Buffer is applied for occlusion detection. The shadow detection can be regarded as a same problem with occlusion detection considering the angle between the sun and the camera. However, the Z-Buffer algorithm is computationally expensive. And the volume of scanned data and remote sensing images is very large. Efficient algorithm is another challenge. Modern graphics processing unit (GPU is much more powerful than central processing unit (CPU. We introduce this technology to speed up the Z-Buffer algorithm and get 7 times increase in speed compared with CPU. The results of experiments demonstrate that Z-Buffer algorithm plays well in occlusion and shadow detection combined with high density of point cloud and GPU can speed up the computation significantly.

  12. Classification of Defoliated Trees Using Tree-Level Airborne Laser Scanning Data Combined with Aerial Images

    Directory of Open Access Journals (Sweden)

    Juha Hyyppa

    2010-11-01

    Full Text Available Climate change and rising temperatures have been observed to be related to the increase of forest insect damage in the boreal zone. The common pine sawfly (Diprion pini L. (Hymenoptera, Diprionidae is regarded as a significant threat to boreal pine forests. Defoliation by D. pini can cause severe growth loss and tree mortality in Scots pine (Pinus sylvestris L. (Pinaceae. In this study, logistic LASSO regression, Random Forest (RF and Most Similar Neighbor method (MSN were investigated for predicting the defoliation level of individual Scots pines using the features derived from airborne laser scanning (ALS data and aerial images. Classification accuracies from 83.7% (kappa 0.67 to 88.1% (kappa 0.76 were obtained depending on the method. The most accurate result was produced using RF with a combination of data from the two sensors, while the accuracies when using ALS and image features separately were 80.7% and 87.4%, respectively. Evidently, the combination of ALS and aerial images in detecting needle losses is capable of providing satisfactory estimates for individual trees.

  13. Combining population and patient-specific characteristics for prostate segmentation on 3D CT images

    Science.gov (United States)

    Ma, Ling; Guo, Rongrong; Tian, Zhiqiang; Venkataraman, Rajesh; Sarkar, Saradwata; Liu, Xiabi; Tade, Funmilayo; Schuster, David M.; Fei, Baowei

    2016-03-01

    Prostate segmentation on CT images is a challenging task. In this paper, we explore the population and patient-specific characteristics for the segmentation of the prostate on CT images. Because population learning does not consider the inter-patient variations and because patient-specific learning may not perform well for different patients, we are combining the population and patient-specific information to improve segmentation performance. Specifically, we train a population model based on the population data and train a patient-specific model based on the manual segmentation on three slice of the new patient. We compute the similarity between the two models to explore the influence of applicable population knowledge on the specific patient. By combining the patient-specific knowledge with the influence, we can capture the population and patient-specific characteristics to calculate the probability of a pixel belonging to the prostate. Finally, we smooth the prostate surface according to the prostate-density value of the pixels in the distance transform image. We conducted the leave-one-out validation experiments on a set of CT volumes from 15 patients. Manual segmentation results from a radiologist serve as the gold standard for the evaluation. Experimental results show that our method achieved an average DSC of 85.1% as compared to the manual segmentation gold standard. This method outperformed the population learning method and the patient-specific learning approach alone. The CT segmentation method can have various applications in prostate cancer diagnosis and therapy.

  14. A Combined First and Second Order Variational Approach for Image Reconstruction

    KAUST Repository

    Papafitsoros, K.

    2013-05-10

    In this paper we study a variational problem in the space of functions of bounded Hessian. Our model constitutes a straightforward higher-order extension of the well known ROF functional (total variation minimisation) to which we add a non-smooth second order regulariser. It combines convex functions of the total variation and the total variation of the first derivatives. In what follows, we prove existence and uniqueness of minimisers of the combined model and present the numerical solution of the corresponding discretised problem by employing the split Bregman method. The paper is furnished with applications of our model to image denoising, deblurring as well as image inpainting. The obtained numerical results are compared with results obtained from total generalised variation (TGV), infimal convolution and Euler\\'s elastica, three other state of the art higher-order models. The numerical discussion confirms that the proposed higher-order model competes with models of its kind in avoiding the creation of undesirable artifacts and blocky-like structures in the reconstructed images-a known disadvantage of the ROF model-while being simple and efficiently numerically solvable. ©Springer Science+Business Media New York 2013.

  15. Intrapleural fibrinolytics combined with image-guided chest tube drainage for pleural infection.

    Science.gov (United States)

    Levinson, Gary M; Pennington, Daniel W

    2007-04-01

    To present our method of treating pleural infection by using a combination of image-guided chest tube drainage and intrapleural fibrinolytics. We retrospectively reviewed the medical charts and radiographs of 30 consecutive patients with pleural infection who were seen at our institution from December 15, 1995, to July 1, 2006, 27 of whom received intrapleural urokinase or tissue-type plasminogen activator. End points were death, length of stay in the hospital, and percentage of patients who needed surgery. Placement of chest tubes required image guidance 45.7% of the time. Three patients (10%; 95% confidence interval, 2.1%-26.5%) died of complications from pleural infection. None of the 30 patients (0%; 95% confidence interval, 0%-9.5%) required surgery for treatment of pleural infection. The median hospital length of stay was 11 days. In the treatment of pleural infection, intrapleural urokinase or tissue-type plasminogen activator in combination with careful image-guided placement of chest tubes is highly effective in resolving the effusion and curing the infection.

  16. Combined Use of Multi-Temporal Optical and Radar Satellite Images for Grassland Monitoring

    Directory of Open Access Journals (Sweden)

    Pauline Dusseux

    2014-06-01

    Full Text Available The aim of this study was to assess the ability of optical images, SAR (Synthetic Aperture Radar images and the combination of both types of data to discriminate between grasslands and crops in agricultural areas where cloud cover is very high most of the time, which restricts the use of visible and near-infrared satellite data. We compared the performances of variables extracted from four optical and five SAR satellite images with high/very high spatial resolutions acquired during the growing season. A vegetation index, namely the NDVI (Normalized Difference Vegetation Index, and two biophysical variables, the LAI (Leaf Area Index and the fCOVER (fraction of Vegetation Cover were computed using optical time series and polarization (HH, VV, HV, VH. The polarization ratio and polarimetric decomposition (Freeman–Durden and Cloude–Pottier were calculated using SAR time series. Then, variables derived from optical, SAR and both types of remotely-sensed data were successively classified using the Support Vector Machine (SVM technique. The results show that the classification accuracy of SAR variables is higher than those using optical data (0.98 compared to 0.81. They also highlight that the combination of optical and SAR time series data is of prime interest to discriminate grasslands from crops, allowing an improved classification accuracy.

  17. Learning and combining image neighborhoods using random forests for neonatal brain disease classification.

    Science.gov (United States)

    Zimmer, Veronika A; Glocker, Ben; Hahner, Nadine; Eixarch, Elisenda; Sanroma, Gerard; Gratacós, Eduard; Rueckert, Daniel; González Ballester, Miguel Ángel; Piella, Gemma

    2017-12-01

    It is challenging to characterize and classify normal and abnormal brain development during early childhood. To reduce the complexity of heterogeneous data population, manifold learning techniques are increasingly applied, which find a low-dimensional representation of the data, while preserving all relevant information. The neighborhood definition used for constructing manifold representations of the population is crucial for preserving the similarity structure and it is highly application dependent. The recently proposed neighborhood approximation forests learn a neighborhood structure in a dataset based on a user-defined distance. We propose a framework to learn multiple pairwise distances in a population of brain images and to combine them in an unsupervised manner optimally in a manifold learning step. Unlike other methods that only use a univariate distance measure, our method allows for a natural combination of multiple distances from heterogeneous sources. As a result, it yields a representation of the population that preserves the multiple distances. Furthermore, our method also selects the most predictive features associated with the distances. We evaluate our method in neonatal magnetic resonance images of three groups (term controls, patients affected by intrauterine growth restriction and mild isolated ventriculomegaly). We show that combining multiple distances related to the condition improves the overall characterization and classification of the three clinical groups compared to the use of single distances and classical unsupervised manifold learning. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Combining MOD10A1 and MYD10A1 Images For Snow Cover Area Monitoring

    Science.gov (United States)

    Tekeli, A. E.

    2008-12-01

    MOD10A1 and MYD10A1 daily snow cover maps at 500 m resolution are available from MODIS sensors on Terra and Aqua satellites. Aqua obtains the image of same region approximately three hours after Terra over Turkey region. MODIS is an optic sensor and cloud cover degrades the usability of derived snow cover maps. Moreover, spectral similarity between clouds and snow complicates their separability in visible imagery. Fortunately, dynamic behavior of clouds enables their discrimination from snow stationary on the surface. Combined use of MOD10A1 and MYD10A1 images mostly reduces the cloud cover present in one image alone and provides better representation of surface snow cover. Comparison of merged images with in situ data indicated higher hit ratios. The individual comparison of MOD10A1 and MYD10A1 images with ground data each yielded 31% hit ratio whereas, the merged images provided 38%. One-day shifts in comparisons increased hit ratios to 52 % and 46% whereas and two-day shifts gave 77 % and 79 % for MOD10A1 and MYD10A1 respectively. Merged maps yielded 54% and 83% for one and two day shifts. The improvement provided by the merging technique is found to be 7% for the present day, 7 % for one- day and 5% for two-day shifts for the whole season. Monthly decomposition resulted 25% improvement as the maximum. The snow cover product obtained by merging Terra and Aqua satellites provided higher hit ratios, as expected.

  19. A combined 3D and hyperspectral method for surface imaging of wounds

    Science.gov (United States)

    Paluchowski, Lukasz A.; Denstedt, Martin; Røren, Thomas; Pukstad, Brita; Randeberg, Lise Lyngsnes

    2013-03-01

    Information about the size and depth of a wound and how it is developing is an important prognostic tool in wound diagnostics. In this study a two-camera vision system has been developed to collect optical properties, shape and volume of chronic skin ulcers as tool for diagnostic assistance. This system combines the functionality of 2D imaging spectroscopy and 3D stereo-photogrammetry. A high resolution hyperspectral camera and a monochromatic video frame camera were mounted on the same scanning system. Stereo images were acquired to obtain information about the wound surface geometry. A Digital Surface Model (DSM) of the wound surface was reconstructed by applying stereophotogrammetric methods. The hyperspectral image was co-registered to the monochromatic frame image and the wound border was extracted by applying spectroscopic analysis (e.g. tissue oxygenation, pigmentation, classification). The resulting DSM of the undamaged surroundings of the wound was used to reconstruct the top surface above the wound and thus the wound volume. The analyses can, if desired, be limited to a certain depth of interest like the wound bed or wound border. Simultaneous analysis of the hyperspectral data and the surface model gives a promising, new, non-invasive tool for characterization of chronic wounds. Future work will concentrate on implementation of real time analysis and improvement of the accuracy of the system.

  20. A new combined technique for automatic contrast enhancement of digital images

    Directory of Open Access Journals (Sweden)

    Ismail A. Humied

    2012-03-01

    Full Text Available Some low contrast images have certain characteristics makes it difficult to use traditional methods to improve it. An example of these characteristics, that the amplitudes of images histogram components are very high at one location on the gray scale and very small in the rest of the gray scale. In the present paper, a new method is described. It can deal with such cases. The proposed method is a combination of Histogram Equalization (HE and Fast Gray-Level Grouping (FGLG. The basic procedure of this method is segments the original histogram of a low contrast image into two sub-histograms according to the location of the highest amplitude of the histogram components, and achieving contrast enhancement by equalizing the left segment of the histogram components using (HE technique and using (FGLG technique to equalize the right segment of this histogram components. The results have shown that the proposed method does not only produce better results than each individual contrast enhancement technique, but it is also fully automated. Moreover, it is applicable to a broad variety of images that satisfy the properties mentioned above and suffer from low contrast.

  1. Algorithms for Image Analysis and Combination of Pattern Classifiers with Application to Medical Diagnosis

    Science.gov (United States)

    Georgiou, Harris

    2009-10-01

    Medical Informatics and the application of modern signal processing in the assistance of the diagnostic process in medical imaging is one of the more recent and active research areas today. This thesis addresses a variety of issues related to the general problem of medical image analysis, specifically in mammography, and presents a series of algorithms and design approaches for all the intermediate levels of a modern system for computer-aided diagnosis (CAD). The diagnostic problem is analyzed with a systematic approach, first defining the imaging characteristics and features that are relevant to probable pathology in mammo-grams. Next, these features are quantified and fused into new, integrated radio-logical systems that exhibit embedded digital signal processing, in order to improve the final result and minimize the radiological dose for the patient. In a higher level, special algorithms are designed for detecting and encoding these clinically interest-ing imaging features, in order to be used as input to advanced pattern classifiers and machine learning models. Finally, these approaches are extended in multi-classifier models under the scope of Game Theory and optimum collective deci-sion, in order to produce efficient solutions for combining classifiers with minimum computational costs for advanced diagnostic systems. The material covered in this thesis is related to a total of 18 published papers, 6 in scientific journals and 12 in international conferences.

  2. Revisit of combined parallel-beam/cone-beam or fan-beam/cone-beam imaging.

    Science.gov (United States)

    Zeng, Gengsheng L

    2013-10-01

    This aim of this paper is to revisit the parallel-beam/cone-beam or fan-beam/cone-beam imaging configuration, and to investigate whether this configuration has any advantages. Twenty years ago, it was suggested to simultaneously use a parallel-beam (or a fan-beam) collimator and a cone-beam collimator to acquire single photon emission computed tomography data. The motivation was that the parallel-beam (or the fan-beam) collimator can provide sufficient sampling, while the cone-beam collimator is able to provide higher photon counts. Even with higher total counts, this hybrid system does not give significant improvement (if any) in terms of image noise and artifacts reduction. If a conventional iterative maximum-likelihood expectation-maximization algorithm is used to reconstruct the image, the resultant reconstruction may be worse than the parallel-beam-only (or fan-beam-only) system. This paper uses the singular value decomposition (SVD) analysis to explain this phenomenon. The SVD results indicate that the parallel-beam-only and the fan-beam-only system outperform the combined systems. The optimal imaging system does not necessary to be the one that generates the projections with highest signal-to-noise ratio and best resolution.

  3. On Classical Ideal Gases

    Directory of Open Access Journals (Sweden)

    Laurent Chusseau

    2013-02-01

    Full Text Available We show that the thermodynamics of ideal gases may be derived solely from the Democritean concept of corpuscles moving in vacuum plus a principle of simplicity, namely that these laws are independent of the laws of motion, aside from the law of energy conservation. Only a single corpuscle in contact with a heat bath submitted to a z and t-invariant force is considered. Most of the end results are known but the method appears to be novel. The mathematics being elementary, the present paper should facilitate the understanding of the ideal gas law and of classical thermodynamics even though not-usually-taught concepts are being introduced.

  4. Note: Grazing incidence small and wide angle x-ray scattering combined with imaging ellipsometry

    Energy Technology Data Exchange (ETDEWEB)

    Koerstgens, V.; Meier, R.; Ruderer, M. A.; Guo, S.; Chiang, H.-Y.; Mueller-Buschbaum, P. [Technische Universitaet Muenchen, Physik-Department, Lehrstuhl fuer Funktionelle Materialien, James-Franck-Str. 1, 85748 Garching (Germany); Perlich, J.; Roth, S. V.; Gehrke, R. [HASYLAB, DESY, Notkestr. 85, 22607, Hamburg (Germany)

    2012-07-15

    The combination of grazing incidence small angle x-ray scattering (GISAXS) and grazing incidence wide angle x-ray scattering (GIWAXS) with optical imaging ellipsometry is presented as an upgrade of the available measurement techniques at the wiggler beamline BW4 of the Hamburger Synchrotronstrahlungslabor. The instrument is introduced with the description of the alignment procedure to assure the measurement of imaging ellipsometry and GISAXS/GIWAXS on the same sample spot. To demonstrate the possibilities of the new instrument examples of morphological investigation on films made of poly(3-hexylthiophene) and [6,6]-phenyl-C{sub 61} butyric acid methyl ester as well as textured poly(9,9-dioctylfluorene-alt-benzo-thia-diazole) are shown.

  5. Combined Néel and Brown rotational Langevin dynamics in magnetic particle imaging, sensing, and therapy

    International Nuclear Information System (INIS)

    Reeves, Daniel B.; Weaver, John B.

    2015-01-01

    Magnetic nanoparticles have been studied intensely because of their possible uses in biomedical applications. Biosensing using the rotational freedom of particles has been used to detect biomarkers for cancer, hyperthermia therapy has been used to treat tumors, and magnetic particle imaging is a promising new imaging modality that can spatially resolve the concentration of nanoparticles. There are two mechanisms by which the magnetization of a nanoparticle can rotate, a fact that poses a challenge for applications that rely on precisely one mechanism. The challenge is exacerbated by the high sensitivity of the dominant mechanism to applied fields. Here, we demonstrate stochastic Langevin equation simulations for the combined rotation in magnetic nanoparticles exposed to oscillating applied fields typical to these applications to both highlight the existing relevant theory and quantify which mechanism should occur in various parameter ranges

  6. Combined Néel and Brown rotational Langevin dynamics in magnetic particle imaging, sensing, and therapy

    Science.gov (United States)

    Reeves, Daniel B.; Weaver, John B.

    2015-11-01

    Magnetic nanoparticles have been studied intensely because of their possible uses in biomedical applications. Biosensing using the rotational freedom of particles has been used to detect biomarkers for cancer, hyperthermia therapy has been used to treat tumors, and magnetic particle imaging is a promising new imaging modality that can spatially resolve the concentration of nanoparticles. There are two mechanisms by which the magnetization of a nanoparticle can rotate, a fact that poses a challenge for applications that rely on precisely one mechanism. The challenge is exacerbated by the high sensitivity of the dominant mechanism to applied fields. Here, we demonstrate stochastic Langevin equation simulations for the combined rotation in magnetic nanoparticles exposed to oscillating applied fields typical to these applications to both highlight the existing relevant theory and quantify which mechanism should occur in various parameter ranges.

  7. Combined Néel and Brown rotational Langevin dynamics in magnetic particle imaging, sensing, and therapy

    Energy Technology Data Exchange (ETDEWEB)

    Reeves, Daniel B., E-mail: dbr@Dartmouth.edu [Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire 03755 (United States); Weaver, John B. [Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire 03755 (United States); Department of Radiology, Geisel School of Medicine, Hanover, New Hampshire 03755 (United States)

    2015-11-30

    Magnetic nanoparticles have been studied intensely because of their possible uses in biomedical applications. Biosensing using the rotational freedom of particles has been used to detect biomarkers for cancer, hyperthermia therapy has been used to treat tumors, and magnetic particle imaging is a promising new imaging modality that can spatially resolve the concentration of nanoparticles. There are two mechanisms by which the magnetization of a nanoparticle can rotate, a fact that poses a challenge for applications that rely on precisely one mechanism. The challenge is exacerbated by the high sensitivity of the dominant mechanism to applied fields. Here, we demonstrate stochastic Langevin equation simulations for the combined rotation in magnetic nanoparticles exposed to oscillating applied fields typical to these applications to both highlight the existing relevant theory and quantify which mechanism should occur in various parameter ranges.

  8. Double contrast barium enema combined with non-invasive imaging in peritoneal mesothelioma

    International Nuclear Information System (INIS)

    Cozzi, G.; Bellomi, M.; Frigerio, L.F.; Ostinelli, C.; Marchiano, A.; Petrillo, R.; Severini, A.; Milan Univ.

    1989-01-01

    Mesotheliomas are rare tumors arising from serosal linings of the major serous cavities. Five patients with peritoneal mesothelioma underwent a double contrast barium enema (DCBE) and ultrasonography (US) (2 patients), computed tomography (CT) (3 patients) and/or magnetic resonance imaging (MRI) (3 patients). The diagnosis was confirmed at laparotomy. The radiologic pattern at DCBE is unspecific and consists of compression and dislocation of bowel loops by extrinsic masses. Mesenteric retraction and segmental stenosis may be present. In one patient DCBE was normal. US, CT and MRI findings are also unspecific but when combined with information obtained from DCBE the site and abdominal extension of the disease are well defined. (orig.)

  9. Monitoring an air pollution episode in Shenzhen by combining MODIS satellite images and the HYSPLIT model

    Science.gov (United States)

    Li, Lili; Liu, Yihong; Wang, Yunpeng

    2017-07-01

    Urban air pollution is influenced not only by local emission sources including industry and vehicles, but also greatly by regional atmospheric pollutant transportation from the surrounding areas, especially in developed city clusters, like the Pearl River Delta (PRD). Taking an air pollution episode in Shenzhen as an example, this paper investigates the occurrence and evolution of the pollution episode and identifies the transport pathways of air pollutants in Shenzhen by combining MODIS satellite images and HYSPLIT back trajectory analysis. Results show that this pollution episode is mainly caused by the local emission of pollutants in PRD and oceanic air masses under specific weather conditions.

  10. Removing radioactive noble gases from nuclear process off-gases

    International Nuclear Information System (INIS)

    Lofredo, A.

    1977-01-01

    A system is claimed for separating, concentrating and storing radioactive krypton and xenon in the off-gases from a boiling water reactor, wherein adsorption and cryogenic distillation are both efficiently used for rapid and positive separation and removal of the radioactive noble gases, and for limiting such gases in circulation in the system to low inventory at all times, and wherein the system is self-regulating to eliminate operator options or attention

  11. Image segmentation for uranium isotopic analysis by SIMS: Combined adaptive thresholding and marker controlled watershed approach

    Energy Technology Data Exchange (ETDEWEB)

    Willingham, David G.; Naes, Benjamin E.; Heasler, Patrick G.; Zimmer, Mindy M.; Barrett, Christopher A.; Addleman, Raymond S.

    2016-05-31

    A novel approach to particle identification and particle isotope ratio determination has been developed for nuclear safeguard applications. This particle search approach combines an adaptive thresholding algorithm and marker-controlled watershed segmentation (MCWS) transform, which improves the secondary ion mass spectrometry (SIMS) isotopic analysis of uranium containing particle populations for nuclear safeguards applications. The Niblack assisted MCWS approach (a.k.a. SEEKER) developed for this work has improved the identification of isotopically unique uranium particles under conditions that have historically presented significant challenges for SIMS image data processing techniques. Particles obtained from five NIST uranium certified reference materials (CRM U129A, U015, U150, U500 and U850) were successfully identified in regions of SIMS image data 1) where a high variability in image intensity existed, 2) where particles were touching or were in close proximity to one another and/or 3) where the magnitude of ion signal for a given region was count limited. Analysis of the isotopic distributions of uranium containing particles identified by SEEKER showed four distinct, accurately identified 235U enrichment distributions, corresponding to the NIST certified 235U/238U isotope ratios for CRM U129A/U015 (not statistically differentiated), U150, U500 and U850. Additionally, comparison of the minor uranium isotope (234U, 235U and 236U) atom percent values verified that, even in the absence of high precision isotope ratio measurements, SEEKER could be used to segment isotopically unique uranium particles from SIMS image data. Although demonstrated specifically for SIMS analysis of uranium containing particles for nuclear safeguards, SEEKER has application in addressing a broad set of image processing challenges.

  12. Neuronal pathology in deep grey matter structures: a multimodal imaging analysis combining PET and MRI

    International Nuclear Information System (INIS)

    Bosque-Freeman, L.; Leroy, C.; Galanaud, D.; Sureau, F.; Assouad, R.; Tourbah, A.; Papeix, C.; Comtat, C.; Trebossen, R.; Lubetzki, C.; Delforge, J.; Bottlaender, M.; Stankoff, B.

    2009-01-01

    Objective: To assess neuronal damage in deep gray matter structures by positron emission tomography (PET) using [ 11 C]-flumazenil (FMZ), a specific central benzodiazepine receptor antagonist, and [ 18 F]-fluorodeoxyglucose (FDG), which reflects neuronal metabolism. To compare results obtained by PET and those with multimodal magnetic resonance imaging (MRI). Background: It is now accepted that neuronal injury plays a crucial role in the occurrence and progression of neurological disability in multiple sclerosis (MS). To date, available MRI techniques do not specifically assess neuronal damage, but early abnormalities, such as iron deposition or atrophy, have been described in deep gray matter structures. Whether those MRI modifications correspond to neuronal damage remains to be further investigated. Materials and methods: Nine healthy volunteers were compared to 10 progressive and 9 relapsing remitting (RR) MS patients. Each subject performed two PET examinations with [ 11 C]-FMZ and [ 18 F]-FDG, on a high resolution research tomograph dedicated to brain imaging (Siemens Medical Solution, spatial resolution of 2.5 mm). Deep gray matter regions were manually segmented on T1-weighted MR images with the mutual information algorithm (www.brainvisa.info), and co-registered with PET images. A multimodal MRI including T1 pre and post gadolinium, T2-proton density sequences, magnetization transfer, diffusion tensor, and protonic spectroscopy was also performed for each subject. Results: On PET with [ 11 C]-FMZ, there was a pronounced decrease in receptor density for RR patients in all deep gray matter structures investigated, whereas the density was unchanged or even increased in the same regions for progressive patients. Whether the different patterns between RR and progressive patients reflect distinct pathogenic mechanisms is currently investigated by comparing PET and multimodal MRI results. Conclusion: Combination of PET and multimodal MR imaging may provide new

  13. 75 FR 14081 - Mandatory Reporting of Greenhouse Gases: Minor Harmonizing Changes to the General Provisions

    Science.gov (United States)

    2010-03-24

    ... AGENCY 40 CFR Part 98 RIN 2060-AQ15 Mandatory Reporting of Greenhouse Gases: Minor Harmonizing Changes to... greenhouse gas suppliers (subpart OO): (A) All producers of industrial greenhouse gases. (B) Importers of industrial greenhouse gases with annual bulk imports of N2O, fluorinated GHG, and CO2 that in combination are...

  14. Detection of colorectal hepatic metastases using MnDPDP MR imaging and diffusion-weighted imaging (DWI) alone and in combination

    International Nuclear Information System (INIS)

    Koh, D.M.; Brown, G.; Riddell, A.M.; Scurr, E.; Allen, S.D.; Husband, J.E.; Collins, D.J.; Souza, N.M. de; Leach, M.O.; Chau, I.; Cunningham, D.

    2008-01-01

    To compare the diagnostic accuracy of MnDPDP MR imaging and diffusion-weighted imaging (DWI), alone and in combination, for detecting colorectal liver metastases in patients with suspected metastatic disease. Thirty-three consecutive patients with suspected colorectal liver metastases underwent MR imaging. Three image sets (MnDPDP, DWI and combined MnDPDP and DWI) were reviewed independently by two observers. Lesions were scored on a five-point scale for malignancy and the areas (Az) under the receiver operating characteristic curves were calculated for each observer and image set. The sensitivity and specificity for lesion detection were calculated for each image set and compared. There were 83 metastases, 49 cysts and 1 haemangioma. Using the combined set resulted in the highest diagnostic accuracy for both observers (Az = 0.94 and 0.96), with improved averaged sensitivity of lesion detection compared with the DWI set (p = 0.01), and a trend towards improved sensitivity compared with the MnDPDP set (p = 0.06). There was no difference in the averaged specificity using any of the three image sets (p > 0.5). Combination of MnDPDP MR imaging and DWI resulted in the highest diagnostic accuracy and can increase sensitivity without loss in specificity. (orig.)

  15. Combined mixed approach algorithm for in-line phase-contrast x-ray imaging

    International Nuclear Information System (INIS)

    De Caro, Liberato; Scattarella, Francesco; Giannini, Cinzia; Tangaro, Sabina; Rigon, Luigi; Longo, Renata; Bellotti, Roberto

    2010-01-01

    Purpose: In the past decade, phase-contrast imaging (PCI) has been applied to study different kinds of tissues and human body parts, with an increased improvement of the image quality with respect to simple absorption radiography. A technique closely related to PCI is phase-retrieval imaging (PRI). Indeed, PCI is an imaging modality thought to enhance the total contrast of the images through the phase shift introduced by the object (human body part); PRI is a mathematical technique to extract the quantitative phase-shift map from PCI. A new phase-retrieval algorithm for the in-line phase-contrast x-ray imaging is here proposed. Methods: The proposed algorithm is based on a mixed transfer-function and transport-of-intensity approach (MA) and it requires, at most, an initial approximate estimate of the average phase shift introduced by the object as prior knowledge. The accuracy in the initial estimate determines the convergence speed of the algorithm. The proposed algorithm retrieves both the object phase and its complex conjugate in a combined MA (CMA). Results: Although slightly less computationally effective with respect to other mixed-approach algorithms, as two phases have to be retrieved, the results obtained by the CMA on simulated data have shown that the obtained reconstructed phase maps are characterized by particularly low normalized mean square errors. The authors have also tested the CMA on noisy experimental phase-contrast data obtained by a suitable weakly absorbing sample consisting of a grid of submillimetric nylon fibers as well as on a strongly absorbing object made of a 0.03 mm thick lead x-ray resolution star pattern. The CMA has shown a good efficiency in recovering phase information, also in presence of noisy data, characterized by peak-to-peak signal-to-noise ratios down to a few dBs, showing the possibility to enhance with phase radiography the signal-to-noise ratio for features in the submillimetric scale with respect to the attenuation

  16. [Research on identification of cabbages and weeds combining spectral imaging technology and SAM taxonomy].

    Science.gov (United States)

    Zu, Qin; Zhang, Shui-fa; Cao, Yang; Zhao, Hui-yi; Dang, Chang-qing

    2015-02-01

    Weeds automatic identification is the key technique and also the bottleneck for implementation of variable spraying and precision pesticide. Therefore, accurate, rapid and non-destructive automatic identification of weeds has become a very important research direction for precision agriculture. Hyperspectral imaging system was used to capture the hyperspectral images of cabbage seedlings and five kinds of weeds such as pigweed, barnyard grass, goosegrass, crabgrass and setaria with the wavelength ranging from 1000 to 2500 nm. In ENVI, by utilizing the MNF rotation to implement the noise reduction and de-correlation of hyperspectral data and reduce the band dimensions from 256 to 11, and extracting the region of interest to get the spectral library as standard spectra, finally, using the SAM taxonomy to identify cabbages and weeds, the classification effect was good when the spectral angle threshold was set as 0. 1 radians. In HSI Analyzer, after selecting the training pixels to obtain the standard spectrum, the SAM taxonomy was used to distinguish weeds from cabbages. Furthermore, in order to measure the recognition accuracy of weeds quantificationally, the statistical data of the weeds and non-weeds were obtained by comparing the SAM classification image with the best classification effects to the manual classification image. The experimental results demonstrated that, when the parameters were set as 5-point smoothing, 0-order derivative and 7-degree spectral angle, the best classification result was acquired and the recognition rate of weeds, non-weeds and overall samples was 80%, 97.3% and 96.8% respectively. The method that combined the spectral imaging technology and the SAM taxonomy together took full advantage of fusion information of spectrum and image. By applying the spatial classification algorithms to establishing training sets for spectral identification, checking the similarity among spectral vectors in the pixel level, integrating the advantages of

  17. Intracranial Vascular Disease Evaluation With Combined Vessel Wall Imaging And Patient Specific Hemodynamics

    Science.gov (United States)

    Samson, Kurt; Mossa-Basha, Mahmud; Yuan, Chun; Canton, Maria De Gador; Aliseda, Alberto

    2017-11-01

    Intracranial vascular pathologies are evaluated with angiography, conventional digital subtraction angiography or non-invasive (MRI, CT). Current techniques present limitations on the resolution with which the vessel wall characteristics can be measured, presenting a major challenge to differential diagnostic of cerebral vasculopathies. A new combined approach is presented that incorporates patient-specific image-based CFD models with intracranial vessel-wall MRI (VWMRI). Comparisons of the VWMRI measurements, evaluated for the presence of wall enhancement and thin-walled regions, against CFD metrics such as wall shear stress (WSS), and oscillatory shear index (OSI) are used to understand how the new imaging technique developed can predict the influence of hemodynamics on the deterioration of the aneurysmal wall, leading to rupture. Additionally, histology of each resected aneurysm, evaluated for inflammatory infiltration and wall thickness features, is used to validate the analysis from VWMRI and CFD. This data presents a solid foundation on which to build a new framework for combined VWMRI-CFD to predict unstable wall changes in unruptured intracranial aneurysms, and support clinical monitoring and intervention decisions.

  18. Grading of Chinese Cantonese Sausage Using Hyperspectral Imaging Combined with Chemometric Methods.

    Science.gov (United States)

    Gong, Aiping; Zhu, Susu; He, Yong; Zhang, Chu

    2017-07-25

    Fast and accurate grading of Chinese Cantonese sausage is an important concern for customers, organizations, and the industry. Hyperspectral imaging in the spectral range of 874-1734 nm, combined with chemometric methods, was applied to grade Chinese Cantonese sausage. Three grades of intact and sliced Cantonese sausages were studied, including the top, first, and second grades. Support vector machine (SVM) and random forests (RF) techniques were used to build two different models. Second derivative spectra and RF were applied to select optimal wavelengths. The optimal wavelengths were the same for intact and sliced sausages when selected from second derivative spectra, while the optimal wavelengths for intact and sliced sausages selected using RF were quite similar. The SVM and RF models, using full spectra and the optimal wavelengths, obtained acceptable results for intact and sliced sausages. Both models for intact sausages performed better than those for sliced sausages, with a classification accuracy of the calibration and prediction set of over 90%. The overall results indicated that hyperspectral imaging combined with chemometric methods could be used to grade Chinese Cantonese sausages, with intact sausages being better suited for grading. This study will help to develop fast and accurate online grading of Cantonese sausages, as well as other sausages.

  19. A Study of Feature Combination for Vehicle Detection Based on Image Processing

    Directory of Open Access Journals (Sweden)

    Jon Arróspide

    2014-01-01

    Full Text Available Video analytics play a critical role in most recent traffic monitoring and driver assistance systems. In this context, the correct detection and classification of surrounding vehicles through image analysis has been the focus of extensive research in the last years. Most of the pieces of work reported for image-based vehicle verification make use of supervised classification approaches and resort to techniques, such as histograms of oriented gradients (HOG, principal component analysis (PCA, and Gabor filters, among others. Unfortunately, existing approaches are lacking in two respects: first, comparison between methods using a common body of work has not been addressed; second, no study of the combination potentiality of popular features for vehicle classification has been reported. In this study the performance of the different techniques is first reviewed and compared using a common public database. Then, the combination capabilities of these techniques are explored and a methodology is presented for the fusion of classifiers built upon them, taking into account also the vehicle pose. The study unveils the limitations of single-feature based classification and makes clear that fusion of classifiers is highly beneficial for vehicle verification.

  20. A study of feature combination for vehicle detection based on image processing.

    Science.gov (United States)

    Arróspide, Jon; Salgado, Luis

    2014-01-01

    Video analytics play a critical role in most recent traffic monitoring and driver assistance systems. In this context, the correct detection and classification of surrounding vehicles through image analysis has been the focus of extensive research in the last years. Most of the pieces of work reported for image-based vehicle verification make use of supervised classification approaches and resort to techniques, such as histograms of oriented gradients (HOG), principal component analysis (PCA), and Gabor filters, among others. Unfortunately, existing approaches are lacking in two respects: first, comparison between methods using a common body of work has not been addressed; second, no study of the combination potentiality of popular features for vehicle classification has been reported. In this study the performance of the different techniques is first reviewed and compared using a common public database. Then, the combination capabilities of these techniques are explored and a methodology is presented for the fusion of classifiers built upon them, taking into account also the vehicle pose. The study unveils the limitations of single-feature based classification and makes clear that fusion of classifiers is highly beneficial for vehicle verification.

  1. Combined TRMM Microwave Imager (TMI) and Precipitation Radar (PR) Gridded Orbital Data Set (G2B31) V6

    Data.gov (United States)

    National Aeronautics and Space Administration — Combined TRMM Microwave Imager (TMI) and Precipitation Radar (PR) gridded orbital rainfall data, is a special product derived from the TRMM standard product (2B-31)...

  2. Origins of geothermal gases at Yellowstone

    Science.gov (United States)

    Lowenstern, Jacob B.; Bergfeld, Deborah; Evans, William C.; Hunt, Andrew G.

    2015-01-01

    Gas emissions at the Yellowstone Plateau Volcanic Field (YPVF) reflect open-system mixing of gas species originating from diverse rock types, magmas, and crustal fluids, all combined in varying proportions at different thermal areas. Gases are not necessarily in chemical equilibrium with the waters through which they vent, especially in acid sulfate terrain where bubbles stream through stagnant acid water. Gases in adjacent thermal areas often can be differentiated by isotopic and gas ratios, and cannot be tied to one another solely by shallow processes such as boiling-induced fractionation of a parent liquid. Instead, they inherit unique gas ratios (e.g., CH4/He) from the dominant rock reservoirs where they originate, some of which underlie the Quaternary volcanic rocks. Steam/gas ratios (essentially H2O/CO2) of Yellowstone fumaroles correlate with Ar/He and N2/CO2, strongly suggesting that H2O/CO2 is controlled by addition of steam boiled from water rich in atmospheric gases. Moreover, H2O/CO2 varies systematically with geographic location, such that boiling is more enhanced in some areas than others. The δ13C and 3He/CO2 of gases reflect a dominant mantle origin for CO2 in Yellowstone gas. The mantle signature is most evident at Mud Volcano, which hosts gases with the lowest H2O/CO2, lowest CH4 concentrations and highest He isotope ratios (~16Ra), consistent with either a young subsurface intrusion or less input of crustal and meteoric gas than any other location at Yellowstone. Across the YPVF, He isotope ratios (3He/4He) inversely vary with He concentrations, and reflect varied amounts of long- stored, radiogenic He added to the magmatic endmember within the crust. Similarly, addition of CH4 from organic-rich sediments is common in the eastern thermal areas at Yellowstone. Overall, Yellowstone gases reflect addition of deep, high-temperature magmatic gas (CO2-rich), lower-temperatures crustal gases (4He- and CH4-bearing), and those gases (N2, Ne, Ar) added

  3. Combining magnetic particle imaging and magnetic fluid hyperthermia in a theranostic platform

    Science.gov (United States)

    Hensley, Daniel; Tay, Zhi Wei; Dhavalikar, Rohan; Zheng, Bo; Goodwill, Patrick; Rinaldi, Carlos; Conolly, Steven

    2017-05-01

    Magnetic particle imaging (MPI) is a rapidly developing molecular and cellular imaging modality. Magnetic fluid hyperthermia (MFH) is a promising therapeutic approach where magnetic nanoparticles are used as a conduit for targeted energy deposition, such as in hyperthermia induction and drug delivery. The physics germane to and exploited by MPI and MFH are similar, and the same particles can be used effectively for both. Consequently, the method of signal localization through the use of gradient fields in MPI can also be used to spatially localize MFH, allowing for spatially selective heating deep in the body and generally providing greater control and flexibility in MFH. Furthermore, MPI and MFH may be integrated together in a single device for simultaneous MPI-MFH and seamless switching between imaging and therapeutic modes. Here we show simulation and experimental work quantifying the extent of spatial localization of MFH using MPI systems: we report the first combined MPI-MFH system and demonstrate on-demand selective heating of nanoparticle samples separated by only 3 mm (up to 0.4 °C s-1 heating rates and 150 W g-1 SAR deposition). We also show experimental data for MPI performed at a typical MFH frequency and show preliminary simultaneous MPI-MFH experimental data.

  4. A combined light sheet fluorescence and differential interference contrast microscope for live imaging of multicellular specimens.

    Science.gov (United States)

    Baker, R P; Taormina, M J; Jemielita, M; Parthasarathy, R

    2015-05-01

    We describe a microscope capable of both light sheet fluorescence microscopy and differential interference contrast microscopy (DICM). The two imaging modes, which to the best of our knowledge have not previously been combined, are complementary: light sheet fluorescence microscopy provides three-dimensional imaging of fluorescently labelled components of multicellular systems with high speed, large fields of view, and low phototoxicity, whereas differential interference contrast microscopy reveals the unlabelled neighbourhood of tissues, organs, and other structures with high contrast and inherent optical sectioning. Use of a single Nomarski prism for differential interference contrast microscopy and a shared detection path for both imaging modes enables simple integration of the two techniques in one custom microscope. We provide several examples of the utility of the resulting instrument, focusing especially on the digestive tract of the larval zebrafish, revealing in this complex and heterogeneous environment anatomical features, the behaviour of commensal microbes, immune cell motions, and more. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.

  5. A bio-electromechanical imaging technique with combined electrical impedance and ultrasound tomography

    International Nuclear Information System (INIS)

    Steiner, G; Watzenig, D; Soleimani, M

    2008-01-01

    Electrical impedance tomography (EIT) seeks to image the electrical conductivity of an object using electrical impedance measurement data at its periphery. Ultrasound reflection tomography (URT) is an imaging modality that is able to generate images of mechanical properties of the object in terms of acoustic impedance changes. Both URT and EIT have the potential to be used in various medical applications. In this paper we focus on breast tumour detection. Both URT and EIT belong to soft field tomography and suffer from the small amounts of available data and the inherently ill-posed nature of the inverse problems. These facts result in limited achievable reconstruction accuracy and resolution. A dual bio-electromechanical tomography system using ultrasound and electrical tomography is proposed in this paper to improve the detection of the small-size tumour. Data fusion techniques are implemented to combine the EIT/URT data. Based on simulations, we demonstrate the improvement of detection of small size anomalies and improved depth detection compared to single modality soft field tomography

  6. A Combinational Clustering Based Method for cDNA Microarray Image Segmentation.

    Directory of Open Access Journals (Sweden)

    Guifang Shao

    Full Text Available Microarray technology plays an important role in drawing useful biological conclusions by analyzing thousands of gene expressions simultaneously. Especially, image analysis is a key step in microarray analysis and its accuracy strongly depends on segmentation. The pioneering works of clustering based segmentation have shown that k-means clustering algorithm and moving k-means clustering algorithm are two commonly used methods in microarray image processing. However, they usually face unsatisfactory results because the real microarray image contains noise, artifacts and spots that vary in size, shape and contrast. To improve the segmentation accuracy, in this article we present a combination clustering based segmentation approach that may be more reliable and able to segment spots automatically. First, this new method starts with a very simple but effective contrast enhancement operation to improve the image quality. Then, an automatic gridding based on the maximum between-class variance is applied to separate the spots into independent areas. Next, among each spot region, the moving k-means clustering is first conducted to separate the spot from background and then the k-means clustering algorithms are combined for those spots failing to obtain the entire boundary. Finally, a refinement step is used to replace the false segmentation and the inseparable ones of missing spots. In addition, quantitative comparisons between the improved method and the other four segmentation algorithms--edge detection, thresholding, k-means clustering and moving k-means clustering--are carried out on cDNA microarray images from six different data sets. Experiments on six different data sets, 1 Stanford Microarray Database (SMD, 2 Gene Expression Omnibus (GEO, 3 Baylor College of Medicine (BCM, 4 Swiss Institute of Bioinformatics (SIB, 5 Joe DeRisi's individual tiff files (DeRisi, and 6 University of California, San Francisco (UCSF, indicate that the improved

  7. A Combinational Clustering Based Method for cDNA Microarray Image Segmentation.

    Science.gov (United States)

    Shao, Guifang; Li, Tiejun; Zuo, Wangda; Wu, Shunxiang; Liu, Tundong

    2015-01-01

    Microarray technology plays an important role in drawing useful biological conclusions by analyzing thousands of gene expressions simultaneously. Especially, image analysis is a key step in microarray analysis and its accuracy strongly depends on segmentation. The pioneering works of clustering based segmentation have shown that k-means clustering algorithm and moving k-means clustering algorithm are two commonly used methods in microarray image processing. However, they usually face unsatisfactory results because the real microarray image contains noise, artifacts and spots that vary in size, shape and contrast. To improve the segmentation accuracy, in this article we present a combination clustering based segmentation approach that may be more reliable and able to segment spots automatically. First, this new method starts with a very simple but effective contrast enhancement operation to improve the image quality. Then, an automatic gridding based on the maximum between-class variance is applied to separate the spots into independent areas. Next, among each spot region, the moving k-means clustering is first conducted to separate the spot from background and then the k-means clustering algorithms are combined for those spots failing to obtain the entire boundary. Finally, a refinement step is used to replace the false segmentation and the inseparable ones of missing spots. In addition, quantitative comparisons between the improved method and the other four segmentation algorithms--edge detection, thresholding, k-means clustering and moving k-means clustering--are carried out on cDNA microarray images from six different data sets. Experiments on six different data sets, 1) Stanford Microarray Database (SMD), 2) Gene Expression Omnibus (GEO), 3) Baylor College of Medicine (BCM), 4) Swiss Institute of Bioinformatics (SIB), 5) Joe DeRisi's individual tiff files (DeRisi), and 6) University of California, San Francisco (UCSF), indicate that the improved approach is

  8. Combination of diffusion tensor and functional magnetic resonance imaging during recovery from the vegetative state

    Directory of Open Access Journals (Sweden)

    Fernández-Espejo Davinia

    2010-09-01

    Full Text Available Abstract Background The rate of recovery from the vegetative state (VS is low. Currently, little is known of the mechanisms and cerebral changes that accompany those relatively rare cases of good recovery. Here, we combined functional magnetic resonance imaging (fMRI and diffusion tensor imaging (DTI to study the evolution of one VS patient at one month post-ictus and again twelve months later when he had recovered consciousness. Methods fMRI was used to investigate cortical responses to passive language stimulation as well as task-induced deactivations related to the default-mode network. DTI was used to assess the integrity of the global white matter and the arcuate fasciculus. We also performed a neuropsychological assessment at the time of the second MRI examination in order to characterize the profile of cognitive deficits. Results fMRI analysis revealed anatomically appropriate activation to speech in both the first and the second scans but a reduced pattern of task-induced deactivations in the first scan. In the second scan, following the recovery of consciousness, this pattern became more similar to that classically described for the default-mode network. DTI analysis revealed relative preservation of the arcuate fasciculus and of the global normal-appearing white matter at both time points. The neuropsychological assessment revealed recovery of receptive linguistic functioning by 12-months post-ictus. Conclusions These results suggest that the combination of different structural and functional imaging modalities may provide a powerful means for assessing the mechanisms involved in the recovery from the VS.

  9. Imaging genetics and the power of combined technologies: a perspective from neuroethics.

    Science.gov (United States)

    Tairyan, K; Illes, J

    2009-11-24

    Imaging genetics has emerged as a powerful and sensitive approach to the study of functional genetic variations and brain responses in psychiatric and neurologic disorders. Ethics issues in contemporary neuroscience as they apply separately to genetics and neuroimaging have been a growing focus for research but, to date, there has not yet been a rigorous exploration of the ethical dimensions of the territory in which they overlap. Here we propose that the ethics challenges associated with the combination of these methods call for an expanded "neuro-space" in which societal and ethical values are closely and explicitly integrated with the new science. We build specifically on the model delivered by Roffman et al. [Roffman JL, Weiss AP, Goff DC, Rauch SL, Weinberger DR (2006) Neuroimaging-genetic paradigms: a new approach to investigate the pathophysiology and treatment of cognitive deficits in schizophrenia. Harv Rev Psychiatry 14:78-91] for neuroimaging, and develop the argument that the ethics issues parallel the heightened discriminative and cumulative power of imaging genetics. In the new combined space, features of discriminative power concern better differentiation of disease, sometimes by ethnicity, and incidental findings. Clinical utility, prediction and intervention, and stigma and labeling reflect a common ground between discriminative and cumulative power. Privacy, autonomy, response sensitivity and attitudes, resource allocation for research and for health care, and commercialization, are features of cumulative power. Parallel to the clinical features highlighted in the Roffman et al. map, the combined space yields additional neuroethics features. These are characterized by new knowledge and new implications for health care, justice, and policy. We conclude by examining these features in the context of public health at the interface of emerging new neurotechnologies.

  10. The Latarjet Procedure at the National Football League Scouting Combine: An Imaging and Performance Analysis.

    Science.gov (United States)

    LeBus, George F; Chahla, Jorge; Sanchez, George; Akamefula, Ramesses; Moatshe, Gilbert; Phocas, Alexandra; Price, Mark D; Whalen, James M; LaPrade, Robert F; Provencher, Matthew T

    2017-09-01

    The Latarjet procedure is commonly performed in the setting of glenoid bone loss for treatment of recurrent anterior shoulder instability; however, little is known regarding the outcomes of this procedure in elite American football players. (1) Determine the prevalence, clinical features, and imaging findings of elite college football athletes who present to the National Football League (NFL) Combine with a previous Latarjet procedure and (2) describe these athletes' performance in the NFL in terms of draft status and initial playing time. Case series; Level of evidence, 4. After review of all football players who participated in the NFL Combine from 2009 to 2016, any player with a previous Latarjet procedure was included in this study. Medical records, position on the field, and draft position were recorded for each player. In addition, imaging studies were reviewed to determine fixation type, hardware complications, and status of the bone block. For those players who were ultimately drafted, performance was assessed based on games played and started, total snaps, and percentage of eligible snaps in which the player participated during his rookie season. Overall, 13 of 2617 (Latarjet procedure. Radiographically, 8 of 13 (61%) showed 2-screw fixation, while 5 of 13 (39%) had 1 screw. Of the 13 players, 6 (46%) players demonstrated hardware complications. All players had evidence of degenerative changes on plain radiographs, with 10 (77%) graded as mild, 1 (8%) as moderate, and 2 (15%) as severe according to the Samilson Prieto classification. Six of the 13 (46%) players went undrafted, while the remaining 7 (54%) were drafted; however, no player participated in more than half of the plays for which he was eligible during his rookie season. Only a small percentage of players at the NFL Combine (Latarjet procedure. High rates of postoperative complications and radiographically confirmed degenerative change were observed. Athletes who had undergone a Latarjet

  11. Paschen's law studies in cold gases

    Science.gov (United States)

    Massarczyk, R.; Chu, P.; Dugger, C.; Elliott, S. R.; Rielage, K.; Xu, W.

    2017-06-01

    The break-through voltage behavior over small gaps has been investigated for differing gap distances, gas pressures, and gas temperatures in nitrogen, neon, argon and xenon gases. A deviation from Paschen's law at micro gap distances has been found. At lower temperatures, a significant shift of the curve relative to the results at room temperature was observed. This behavior can be explained by combining Paschen's law and the ideal gas law.

  12. Paschen's law studies in cold gases

    OpenAIRE

    Massarczyk, R.; Chu, P.; Elliott, S. R.; Rielage, K.; Dugger, C.; Xu, W.

    2016-01-01

    The break-through voltage over small gaps has been investigated for differing gap distances, gas pressures, and gas temperatures in nitrogen, neon, argon and xenon gases. A deviation from Paschen's law at micro gap distances has been found. The breakthrough behavior of the fill gas in colder environments was tested as well. A significant shift of the curve relative to the results at room temperature was observed. The results can be explained by combining Paschen's law and the ideal gas law.

  13. Selective noble gases monitoring

    International Nuclear Information System (INIS)

    Janecka, S.; Jancik, O.; Kapisovsky, V.; Kubik, I.; Sevecka, S.

    1995-01-01

    The monitoring of leak releases from ventilation stack of NPP requires a system by several orders more sensitive then currently used radiometer Kalina, designed to cover the range up to a design-based accident. To reach this goal a noble gases monitor with a germanium detector (MPVG) has been developed. It enables nuclide selective monitoring of current value of volume activity of particular nuclides in ventilation stack and daily releases of noble gases (balancing). MPVG can be viewed as a system build of three levels of subsystem: measuring level; control level; presentation level. Measuring level consists of gamma-spectroscopy system and operational parameters monitoring unit (flow rate, temperature, humidity). Control level provides communication between presentation and measuring level, acquisition of operational parameters and power supply. The presentation level of MPVG enables: 1) the measured data storage in predetermined time intervals; 2) the presentation of measured and evaluated values of radiation characteristics. The monitored radionuclides - default set: argon-41, krypton-85m, krypton-87, krypton-88, krypton-89, xenon-131m, xenon-133, xenon-133m, xenon-135, xenon-135m, xenon-137 and xenon-138. The values of volume activities observed at maximum releases have been approximately ten times higher. In that case in balancing some other nuclides exceed corresponding detection limits: 88 Kr(67; 22) Bq/m 3 ; 85m Kr(17; 7) Bq/m 3 ; 135m Xe(7.1; 0.5) Bq/m 3 ; 138 Xe(5.9; 0.9) Bq/m 3 . (J.K.)

  14. Effects of temperature and irradiance on a benthic microalgal community: A combined two-dimensional oxygen and fluorescence imaging approach

    DEFF Research Database (Denmark)

    Hancke, Kasper; Sorrell, Brian Keith; Lund-Hansen, Lars Chresten

    2014-01-01

    The effects of temperature and light on both oxygen (O2) production and gross photosynthesis were resolved in a benthic microalgae community by combining two-dimensional (2D) imaging of O2 and variable chlorophyll a (Chl a) fluorescence. Images revealed a photosynthetically active community with ...

  15. Experimental study on solids circulation patterns and bubble behavior using particle imagevelocimetry combined with digital image analysis

    NARCIS (Netherlands)

    Laverman, J.A.; Roghair, Ivo; van Sint Annaland, M.; Kuipers, J.A.M.

    2008-01-01

    The hydrodynamics, viz. the solids circulation patterns and bubble behavior, of a freely bubbling gas-solid fluidized bed has been investigated experimentally using Particle Image Velocimetry (PIV) combined with Digital Image Analysis (DIA). Coupling of these non-invasive measuring techniques allows

  16. Combined blood pool and extracellular contrast agents for pediatric and young adult cardiovascular magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Joyce T. [Ann and Robert Lurie Children' s Hospital of Chicago, Division of Pediatric Cardiology, 225 E. Chicago Ave., Box 21, Chicago, IL (United States); Ann and Robert Lurie Children' s Hospital of Chicago, Department of Pediatrics, Chicago, IL (United States); Robinson, Joshua D. [Ann and Robert Lurie Children' s Hospital of Chicago, Division of Pediatric Cardiology, 225 E. Chicago Ave., Box 21, Chicago, IL (United States); Ann and Robert Lurie Children' s Hospital of Chicago, Department of Pediatrics, Chicago, IL (United States); Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); Deng, Jie [Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); Ann and Robert Lurie Children' s Hospital of Chicago, Department of Medical Imaging, Chicago, IL (United States); Rigsby, Cynthia K. [Ann and Robert Lurie Children' s Hospital of Chicago, Department of Pediatrics, Chicago, IL (United States); Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); Ann and Robert Lurie Children' s Hospital of Chicago, Department of Medical Imaging, Chicago, IL (United States)

    2016-12-15

    A comprehensive cardiac magnetic resonance (cardiac MR) study including both late gadolinium enhancement (LGE) and MR angiography may be indicated for patients with a history of acquired or congenital heart disease. To study the novel use of an extracellular agent for assessment of LGE combined with a blood pool contrast agent for detailed MR angiography evaluation to yield a comprehensive cardiac MR study in these patients. We reviewed clinical cardiac MR studies utilizing extracellular and blood pool contrast agents and noted demographics, clinical data and adverse events. We rated LGE image quality and MR angiography image quality for each vascular segment and calculated inter-rater variability. We also quantified contrast-to-noise ratio (CNR). Thirty-three patients (mean age 13.9 ± 3 years) received an extracellular contrast agent (10 gadobenate dimeglumine, 23 gadopentetate dimeglumine) and blood pool contrast agent (33 gadofosveset trisodium). No adverse events were reported. MRI indications included Kawasaki disease (8), cardiomyopathy and coronary anatomy (15), repaired congenital heart disease (8), and other (2). Mean LGE quality was 2.6 ± 0.6 with 97% diagnostic imaging. LGE quality did not vary by type of contrast agent given (P = 0.07). Mean MR angiography quality score was 4.7 ± 0.6, with high inter-rater agreement (k = 0.6-0.8, P < 0.002). MR angiography quality did not vary by type of contrast agent used (P = 0.6). Cardiac MR studies utilizing both extracellular and blood pool contrast agents are feasible and safe and provide excellent-quality LGE and MR angiography images. The use of two contrast agents allows for a comprehensive assessment of both myocardial viability and vascular anatomy during the same exam. (orig.)

  17. A combined positron emission tomography (PET)- electron paramagnetic resonance imaging (EPRI) system: initial evaluation of a prototype scanner.

    Science.gov (United States)

    Tseytlin, Mark; Stolin, Alexander V; Guggilapu, Priyaankadevi; Bobko, Andrey A; Khramtsov, Valery V; Tseytlin, Oxana; Raylman, Raymond R

    2018-04-20

    The advent of hybrid scanners, combining complementary modalities, has revolutionized imaging; enhancing clinical practice and biomedical research. In this project, we investigated the melding of two complementary, functional imaging methods: positron emission tomography (PET) and electron paramagnetic resonance imaging (EPRI). The PET radiotracers can provide important information about cellular parameters, such as glucose metabolism. While EPR probes can provide assessment of tissue microenvironment, measuring parameters such as oxygenation and pH, for example. A combined PET/EPRI scanner has the promise to provide new insights not attainable with current imagers by simultaneous acquisition of multiple components of tissue microenvironments. In this investigation, a prototype system was created by combing two existing scanners, modified for simultaneous imaging. Specifically, a silicon photomultiplier (SiPM) based PET scanner ring designed as a portable scanner was combined with an EPRI scanner designed for the imaging of small animals. The ability of the system to obtain simultaneous images was assessed with a small phantom consisting of four cylinders containing both PET and EPR tracers. The resulting images demonstrated the ability to obtain contemporaneous PET and ERP images without cross-modality interference. The next step in this project is the construction of pre-clinical PET/EPRI scanner for multi-parametric assessment of physiologically important parameters of tissue microenvironments. . © 2018 Institute of Physics and Engineering in Medicine.

  18. Atorvastatin effect evaluation based on feature combination of three-dimension ultrasound images

    Science.gov (United States)

    Luo, Yongkang; Ding, Mingyue

    2016-03-01

    In the past decades, stroke has become the worldwide common cause of death and disability. It is well known that ischemic stroke is mainly caused by carotid atherosclerosis. As an inexpensive, convenient and fast means of detection, ultrasound technology is applied widely in the prevention and treatment of carotid atherosclerosis. Recently, many studies have focused on how to quantitatively evaluate local arterial effects of medicine treatment for carotid diseases. So the evaluation method based on feature combination was proposed to detect potential changes in the carotid arteries after atorvastatin treatment. And the support vector machine (SVM) and 10-fold cross-validation protocol were utilized on a database of 5533 carotid ultrasound images of 38 patients (17 atorvastatin groups and 21 placebo groups) at baseline and after 3 months of the treatment. With combination optimization of many features (including morphological and texture features), the evaluation results of single feature and different combined features were compared. The experimental results showed that the performance of single feature is poor and the best feature combination have good recognition ability, with the accuracy 92.81%, sensitivity 80.95%, specificity 95.52%, positive predictive value 80.47%, negative predictive value 95.65%, Matthew's correlation coefficient 76.27%, and Youden's index 76.48%. And the receiver operating characteristic (ROC) curve was also performed well with 0.9663 of the area under the ROC curve (AUC), which is better than all the features with 0.9423 of the AUC. Thus, it is proved that this novel method can reliably and accurately evaluate the effect of atorvastatin treatment.

  19. Spectral-spatial classification combined with diffusion theory based inverse modeling of hyperspectral images

    Science.gov (United States)

    Paluchowski, Lukasz A.; Bjorgan, Asgeir; Nordgaard, Hâvard B.; Randeberg, Lise L.

    2016-02-01

    Hyperspectral imagery opens a new perspective for biomedical diagnostics and tissue characterization. High spectral resolution can give insight into optical properties of the skin tissue. However, at the same time the amount of collected data represents a challenge when it comes to decomposition into clusters and extraction of useful diagnostic information. In this study spectral-spatial classification and inverse diffusion modeling were employed to hyperspectral images obtained from a porcine burn model using a hyperspectral push-broom camera. The implemented method takes advantage of spatial and spectral information simultaneously, and provides information about the average optical properties within each cluster. The implemented algorithm allows mapping spectral and spatial heterogeneity of the burn injury as well as dynamic changes of spectral properties within the burn area. The combination of statistical and physics informed tools allowed for initial separation of different burn wounds and further detailed characterization of the injuries in short post-injury time.

  20. The natural combination of full and image-based waveform inversion

    KAUST Repository

    Alkhalifah, Tariq Ali

    2015-06-01

    Integrating migration velocity analysis and full waveform inversion can help reduce the high non-linearity of the classic full waveform inversion objective function. The combination of inverting for the long and short wavelength components of the velocity model using a dual objective function that is sensitive to both components is still very expensive and have produced mixed results. We develop an approach that includes both components integrated to complement each other. We specifically utilize the image to generate reflections in our synthetic data only when the velocity model is not capable of producing such reflections. As a result, we get the migration velocity analysis working when we need it, and we mitigate its influence when the velocity model produces accurate reflections (possibly first for the low frequencies). This is achieved using a novel objective function that includes both objectives. Applications to a layered model and the Marmousi model demonstrate the main features of the approach. © 2015 European Association of Geoscientists & Engineers.

  1. Assessment of attenuation correction for myocardial PET imaging using combined PET/MRI.

    Science.gov (United States)

    Lassen, Martin Lyngby; Rasul, Sazan; Beitzke, Dietrich; Stelzmüller, Marie-Elisabeth; Cal-Gonzalez, Jacobo; Hacker, Marcus; Beyer, Thomas

    2017-11-22

    To evaluate the frequency of artifacts in MR-based attenuation correction (AC) maps and their impact on the quantitative accuracy of PET-based flow and metabolism measurements in a cohort of consecutive heart failure patients undergoing combined PET/MR imaging. Myocardial viability studies were performed in 20 patients following a dual-tracer protocol involving the assessment of myocardial perfusion ( 13 N-NH 3 : 813 ± 86 MBq) and metabolism ( 18 F-FDG: 335 ± 38 MBq). All acquisitions were performed using a fully-integrated PET/MR system, with standard DIXON-attenuation correction (DIXON-AC) mapping for each PET scan. All AC maps were examined for spatial misalignment with the emission data, total lung volume, susceptibility artifacts, and tissue inversion (TI). Misalignment and susceptibility artifacts were corrected using rigid co-registration and retrospective filling of the susceptibility-induced gaps, respectively. The effects of the AC artifacts were evaluated by relative difference measures and perceived changes in clinical interpretations. Average respiratory misalignment of (7 ± 4) mm of the PET-emission data and the AC maps was observed in 18 (90%) patients. Substantial changes in the lung volumes of the AC maps were observed in the test-retest analysis (ratio: 1.0 ± 0.2, range: 0.8-1.4). Susceptibility artifacts were observed in 10 (50%) patients, while six (30%) patients had TI artifacts. Average differences of 14 ± 10% were observed for PET images reconstructed with the artifactual AC maps. The combined artifact effects caused false-positive findings in three (15%) patients. Standard DIXON-AC maps must be examined carefully for artifacts and misalignment effects prior to AC correction of cardiac PET/MRI studies in order to avoid misinterpretation of biased perfusion and metabolism readings from the PET data.

  2. Diagnostic performance of combined noninvasive coronary angiography and myocardial perfusion imaging using 320 row detector computed tomography

    DEFF Research Database (Denmark)

    Vavere, Andrea L; Simon, Gregory G; George, Richard T

    2013-01-01

    the diagnostic performance of combined 320-row CTA and myocardial CT perfusion imaging (CTP) in comparison with the combination of invasive coronary angiography and single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI). The trial is being performed at 16 medical centers located in 8...... to detect myocardial ischemia. In this article, we describe the design of the CORE320 study ("Combined coronary atherosclerosis and myocardial perfusion evaluation using 320 detector row computed tomography"). This prospective, multicenter, multinational study is unique in that it is designed to assess...... countries worldwide. CT has the potential to assess both anatomy and physiology in a single imaging session. The co-primary aim of the CORE320 study is to define the per-patient diagnostic accuracy of the combination of coronary CTA and myocardial CTP to detect physiologically significant coronary artery...

  3. ON THE COMBINATION OF IMAGING-POLARIMETRY WITH SPECTROPOLARIMETRY OF UPPER SOLAR ATMOSPHERES DURING SOLAR ECLIPSES

    International Nuclear Information System (INIS)

    Qu, Z. Q.; Deng, L. H.; Dun, G. T.; Chang, L.; Zhang, X. Y.; Cheng, X. M.; Qu, Z. N.; Xue, Z. K.; Ma, L.; Allington-Smith, J.; Murray, G.

    2013-01-01

    We present results from imaging polarimetry (IP) of upper solar atmospheres during a total solar eclipse on 2012 November 13 and spectropolarimetry of an annular solar eclipse on 2010 January 15. This combination of techniques provides both the synoptic spatial distribution of polarization above the solar limb and spectral information on the physical mechanism producing the polarization. Using these techniques together we demonstrate that even in the transition region, the linear polarization increases with height and can exceed 20%. IP shows a relatively smooth background distribution in terms of the amplitude and direction modified by solar structures above the limb. A map of a new quantity that reflects direction departure from the background polarization supplies an effective technique to improve the contrast of this fine structure. Spectral polarimetry shows that the relative contribution to the integrated polarization over the observed passband from the spectral lines decreases with height while the contribution from the continuum increases as a general trend. We conclude that both imaging and spectral polarimetry obtained simultaneously over matched spatial and spectral domains will be fruitful for future eclipse observations

  4. Combined Source-Channel Coding of Images under Power and Bandwidth Constraints

    Directory of Open Access Journals (Sweden)

    Fossorier Marc

    2007-01-01

    Full Text Available This paper proposes a framework for combined source-channel coding for a power and bandwidth constrained noisy channel. The framework is applied to progressive image transmission using constant envelope -ary phase shift key ( -PSK signaling over an additive white Gaussian noise channel. First, the framework is developed for uncoded -PSK signaling (with . Then, it is extended to include coded -PSK modulation using trellis coded modulation (TCM. An adaptive TCM system is also presented. Simulation results show that, depending on the constellation size, coded -PSK signaling performs 3.1 to 5.2 dB better than uncoded -PSK signaling. Finally, the performance of our combined source-channel coding scheme is investigated from the channel capacity point of view. Our framework is further extended to include powerful channel codes like turbo and low-density parity-check (LDPC codes. With these powerful codes, our proposed scheme performs about one dB away from the capacity-achieving SNR value of the QPSK channel.

  5. Sensing Noncollinear Magnetism at the Atomic Scale Combining Magnetic Exchange and Spin-Polarized Imaging.

    Science.gov (United States)

    Hauptmann, Nadine; Gerritsen, Jan W; Wegner, Daniel; Khajetoorians, Alexander A

    2017-09-13

    Storing and accessing information in atomic-scale magnets requires magnetic imaging techniques with single-atom resolution. Here, we show simultaneous detection of the spin-polarization and exchange force with or without the flow of current with a new method, which combines scanning tunneling microscopy and noncontact atomic force microscopy. To demonstrate the application of this new method, we characterize the prototypical nanoskyrmion lattice formed on a monolayer of Fe/Ir(111). We resolve the square magnetic lattice by employing magnetic exchange force microscopy, demonstrating its applicability to noncollinear magnetic structures for the first time. Utilizing distance-dependent force and current spectroscopy, we quantify the exchange forces in comparison to the spin-polarization. For strongly spin-polarized tips, we distinguish different signs of the exchange force that we suggest arises from a change in exchange mechanisms between the probe and a skyrmion. This new approach may enable both nonperturbative readout combined with writing by current-driven reversal of atomic-scale magnets.

  6. Canonical partition functions: ideal quantum gases, interacting classical gases, and interacting quantum gases

    Science.gov (United States)

    Zhou, Chi-Chun; Dai, Wu-Sheng

    2018-02-01

    In statistical mechanics, for a system with a fixed number of particles, e.g. a finite-size system, strictly speaking, the thermodynamic quantity needs to be calculated in the canonical ensemble. Nevertheless, the calculation of the canonical partition function is difficult. In this paper, based on the mathematical theory of the symmetric function, we suggest a method for the calculation of the canonical partition function of ideal quantum gases, including ideal Bose, Fermi, and Gentile gases. Moreover, we express the canonical partition functions of interacting classical and quantum gases given by the classical and quantum cluster expansion methods in terms of the Bell polynomial in mathematics. The virial coefficients of ideal Bose, Fermi, and Gentile gases are calculated from the exact canonical partition function. The virial coefficients of interacting classical and quantum gases are calculated from the canonical partition function by using the expansion of the Bell polynomial, rather than calculated from the grand canonical potential.

  7. Combining Haar Wavelet and Karhunen Loeve Transforms for Medical Images Watermarking

    Directory of Open Access Journals (Sweden)

    Mohamed Ali Hajjaji

    2014-01-01

    Full Text Available This paper presents a novel watermarking method, applied to the medical imaging domain, used to embed the patient’s data into the corresponding image or set of images used for the diagnosis. The main objective behind the proposed technique is to perform the watermarking of the medical images in such a way that the three main attributes of the hidden information (i.e., imperceptibility, robustness, and integration rate can be jointly ameliorated as much as possible. These attributes determine the effectiveness of the watermark, resistance to external attacks, and increase the integration rate. In order to improve the robustness, a combination of the characteristics of Discrete Wavelet and Karhunen Loeve Transforms is proposed. The Karhunen Loeve Transform is applied on the subblocks (sized 8×8 of the different wavelet coefficients (in the HL2, LH2, and HH2 subbands. In this manner, the watermark will be adapted according to the energy values of each of the Karhunen Loeve components, with the aim of ensuring a better watermark extraction under various types of attacks. For the correct identification of inserted data, the use of an Errors Correcting Code (ECC mechanism is required for the check and, if possible, the correction of errors introduced into the inserted data. Concerning the enhancement of the imperceptibility factor, the main goal is to determine the optimal value of the visibility factor, which depends on several parameters of the DWT and the KLT transforms. As a first step, a Fuzzy Inference System (FIS has been set up and then applied to determine an initial visibility factor value. Several features extracted from the Cooccurrence matrix are used as an input to the FIS and used to determine an initial visibility factor for each block; these values are subsequently reweighted in function of the eigenvalues extracted from each subblock. Regarding the integration rate, the previous works insert one bit per coefficient. In our

  8. Noble gases solubility in water

    International Nuclear Information System (INIS)

    Crovetto, Rosa; Fernandez Prini, Roberto.

    1980-07-01

    The available experimental data of solubility of noble gases in water for temperatures smaller than 330 0 C have been critically surveyed. Due to the unique structure of the solvent, the solubility of noble gases in water decreases with temperature passing through a temperature of minimum solubility which is different for each gas, and then increases at higher temperatures. As aresult of the analysis of the experimental data and of the features of the solute-solvent interaction, a generalized equation is proposed which enables thecalculation of Henry's coefficient at different temperatures for all noble gases. (author) [es

  9. Combined magnetic resonance and optical imaging of head and neck tumor xenografts using Gadolinium-labelled phosphorescent polymeric nanomicelles

    Science.gov (United States)

    2010-01-01

    Background The overall objective of this study was to develop a nanoparticle formulation for dual modality imaging of head and neck cancer. Here, we report the synthesis and characterization of polymeric phospholipid-based nanomicelles encapsulating near-infrared (NIR) phosphorescent molecules of Pt(II)-tetraphenyltetranaphthoporphyrin [Pt(TPNP)] and surface functionalized with gadolinium [Pt(TPNP)-Gd] for combined magnetic resonance imaging (MRI) and NIR optical imaging applications. Methods Dynamic light scattering, electron microscopy, optical spectroscopy and MR relaxometric measurements were performed to characterize the optical and magnetic properties of nanoparticles in vitro. Subsequently, in vivo imaging experiments were carried out using nude mice bearing primary patient tumor-derived human head and neck squamous cell carcinoma xenografts. Results The nanomicelles were ~100 nm in size and stable in aqueous suspension. T1-weighted MRI and relaxation rate (R1 = 1/T1) measurements carried out at 4.7 T revealed enhancement in the tumor immediately post injection with nanomicelles, particularly in the tumor periphery which persisted up to 24 hours post administration. Maximum intensity projections (MIPs) generated from 3D T1-weighted images also demonstrated visible enhancement in contrast within the tumor, liver and blood vessels. NIR optical imaging performed (in vivo and ex vivo) following completion of MRI at the 24 h time point confirmed tumor localization of the nanoparticles. The large spectral separation between the Pt(TPNP) absorption (~700 nm) and phosphorescence emission (~900 nm) provided a dramatic decrease in the level of background, resulting in high contrast optical (NIR phosphorescence) imaging. Conclusions In conclusion, Pt(TPNP)-Gd nanomicelles exhibit a high degree of tumor-avidity and favorable imaging properties that allow for combined MR and optical imaging of head and neck tumors. Further investigation into the potential of Pt

  10. Combined ultrasound and MR imaging to guide focused ultrasound therapies in the brain

    International Nuclear Information System (INIS)

    Arvanitis, Costas D; McDannold, Nathan; Livingstone, Margaret S

    2013-01-01

    Several emerging therapies with potential for use in the brain, harness effects produced by acoustic cavitation—the interaction between ultrasound and microbubbles either generated during sonication or introduced into the vasculature. Systems developed for transcranial MRI-guided focused ultrasound (MRgFUS) thermal ablation can enable their clinical translation, but methods for real-time monitoring and control are currently lacking. Acoustic emissions produced during sonication can provide information about the location, strength and type of the microbubble oscillations within the ultrasound field, and they can be mapped in real-time using passive imaging approaches. Here, we tested whether such mapping can be achieved transcranially within a clinical brain MRgFUS system. We integrated an ultrasound imaging array into the hemisphere transducer of the MRgFUS device. Passive cavitation maps were obtained during sonications combined with a circulating microbubble agent at 20 targets in the cingulate cortex in three macaques. The maps were compared with MRI-evident tissue effects. The system successfully mapped microbubble activity during both stable and inertial cavitation, which was correlated with MRI-evident transient blood–brain barrier disruption and vascular damage, respectively. The location of this activity was coincident with the resulting tissue changes within the expected resolution limits of the system. While preliminary, these data clearly demonstrate, for the first time, that it is possible to construct maps of stable and inertial cavitation transcranially, in a large animal model, and under clinically relevant conditions. Further, these results suggest that this hybrid ultrasound/MRI approach can provide comprehensive guidance for targeted drug delivery via blood–brain barrier disruption and other emerging ultrasound treatments, facilitating their clinical translation. We anticipate that it will also prove to be an important research tool that

  11. Combined micro-XRF and TXRF methodology for quantitative elemental imaging of tissue samples.

    Science.gov (United States)

    Wróbel, Paweł M; Bała, Sławomir; Czyzycki, Mateusz; Golasik, Magdalena; Librowski, Tadeusz; Ostachowicz, Beata; Piekoszewski, Wojciech; Surówka, Artur; Lankosz, Marek

    2017-01-01

    Local differences in structural properties of biological specimens pose a major limitation to quantitative X-ray fluorescence imaging. This is because both the various tissue compartments of different density and variation in the sample thickness upon frequently used freeze-drying come up with the different values of the sample mass per unit area to be taken into account. Even though several solutions to tackle this problem based on the home-made standards for quantification in terms of thickness- and density-independent elemental mass fractions have been proposed, this issue is not addressed enough due to the samples' heterogeneity. In our recent study, we propose a calculation scheme based on combined external-standard micro X-ray fluorescence (micro-XRF) imaging and internal-standard total reflection X-ray fluorescence (TXRF) analysis to determine the corrected elemental mass fraction distributions in commonly analysed rat tissues: kidney, liver and spleen. The results of TXRF analysis of digested large tissue sections together with the mean values of elemental masses per unit area obtained with micro-XRF were employed to determine the average masses per unit area of the samples. The correction for variation of the tissue thickness and density was done through with the use of Compton intensities. Importantly, by its versatility, our novel approach can be used to produce elemental contrast in a variety of biological specimens where local variations in either the sample density or thickness are no longer the issue. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Active Breathing Control in Combination With Ultrasound Imaging: A Feasibility Study of Image Guidance in Stereotactic Body Radiation Therapy of Liver Lesions

    International Nuclear Information System (INIS)

    Bloemen-van Gurp, Esther; Meer, Skadi van der; Hendry, Janet; Buijsen, Jeroen; Visser, Peter; Fontanarosa, Davide; Lachaine, Martin; Lammering, Guido; Verhaegen, Frank

    2013-01-01

    Purpose: Accurate tumor positioning in stereotactic body radiation therapy (SBRT) of liver lesions is often hampered by motion and setup errors. We combined 3-dimensional ultrasound imaging (3DUS) and active breathing control (ABC) as an image guidance tool. Methods and Materials: We tested 3DUS image guidance in the SBRT treatment of liver lesions for 11 patients with 88 treatment fractions. In 5 patients, 3DUS imaging was combined with ABC. The uncertainties of US scanning and US image segmentation in liver lesions were determined with and without ABC. Results: In free breathing, the intraobserver variations were 1.4 mm in left-right (L-R), 1.6 mm in superior-inferior (S-I), and 1.3 mm anterior-posterior (A-P). and the interobserver variations were 1.6 mm (L-R), 2.8 mm (S-I), and 1.2 mm (A-P). The combined uncertainty of US scanning and matching (inter- and intraobserver) was 4 mm (1 SD). The combined uncertainty when ABC was used reduced by 1.7 mm in the S-I direction. For the L-R and A-P directions, no significant difference was observed. Conclusion: 3DUS imaging for IGRT of liver lesions is feasible, although using anatomic surrogates in the close vicinity of the lesion may be needed. ABC-based breath-hold in midventilation during 3DUS imaging can reduce the uncertainty of US-based 3D table shift correction

  13. Modeling Soil Organic Carbon at Regional Scale by Combining Multi-Spectral Images with Laboratory Spectra.

    Directory of Open Access Journals (Sweden)

    Yi Peng

    Full Text Available There is a great challenge in combining soil proximal spectra and remote sensing spectra to improve the accuracy of soil organic carbon (SOC models. This is primarily because mixing of spectral data from different sources and technologies to improve soil models is still in its infancy. The first objective of this study was to integrate information of SOC derived from visible near-infrared reflectance (Vis-NIR spectra in the laboratory with remote sensing (RS images to improve predictions of topsoil SOC in the Skjern river catchment, Denmark. The second objective was to improve SOC prediction results by separately modeling uplands and wetlands. A total of 328 topsoil samples were collected and analyzed for SOC. Satellite Pour l'Observation de la Terre (SPOT5, Landsat Data Continuity Mission (Landsat 8 images, laboratory Vis-NIR and other ancillary environmental data including terrain parameters and soil maps were compiled to predict topsoil SOC using Cubist regression and Bayesian kriging. The results showed that the model developed from RS data, ancillary environmental data and laboratory spectral data yielded a lower root mean square error (RMSE (2.8% and higher R2 (0.59 than the model developed from only RS data and ancillary environmental data (RMSE: 3.6%, R2: 0.46. Plant-available water (PAW was the most important predictor for all the models because of its close relationship with soil organic matter content. Moreover, vegetation indices, such as the Normalized Difference Vegetation Index (NDVI and Enhanced Vegetation Index (EVI, were very important predictors in SOC spatial models. Furthermore, the 'upland model' was able to more accurately predict SOC compared with the 'upland & wetland model'. However, the separately calibrated 'upland and wetland model' did not improve the prediction accuracy for wetland sites, since it was not possible to adequately discriminate the vegetation in the RS summer images. We conclude that laboratory Vis

  14. Combining Deep and Handcrafted Image Features for Presentation Attack Detection in Face Recognition Systems Using Visible-Light Camera Sensors

    Directory of Open Access Journals (Sweden)

    Dat Tien Nguyen

    2018-02-01

    Full Text Available Although face recognition systems have wide application, they are vulnerable to presentation attack samples (fake samples. Therefore, a presentation attack detection (PAD method is required to enhance the security level of face recognition systems. Most of the previously proposed PAD methods for face recognition systems have focused on using handcrafted image features, which are designed by expert knowledge of designers, such as Gabor filter, local binary pattern (LBP, local ternary pattern (LTP, and histogram of oriented gradients (HOG. As a result, the extracted features reflect limited aspects of the problem, yielding a detection accuracy that is low and varies with the characteristics of presentation attack face images. The deep learning method has been developed in the computer vision research community, which is proven to be suitable for automatically training a feature extractor that can be used to enhance the ability of handcrafted features. To overcome the limitations of previously proposed PAD methods, we propose a new PAD method that uses a combination of deep and handcrafted features extracted from the images by visible-light camera sensor. Our proposed method uses the convolutional neural network (CNN method to extract deep image features and the multi-level local binary pattern (MLBP method to extract skin detail features from face images to discriminate the real and presentation attack face images. By combining the two types of image features, we form a new type of image features, called hybrid features, which has stronger discrimination ability than single image features. Finally, we use the support vector machine (SVM method to classify the image features into real or presentation attack class. Our experimental results indicate that our proposed method outperforms previous PAD methods by yielding the smallest error rates on the same image databases.

  15. Combining Deep and Handcrafted Image Features for Presentation Attack Detection in Face Recognition Systems Using Visible-Light Camera Sensors

    Science.gov (United States)

    Nguyen, Dat Tien; Pham, Tuyen Danh; Baek, Na Rae; Park, Kang Ryoung

    2018-01-01

    Although face recognition systems have wide application, they are vulnerable to presentation attack samples (fake samples). Therefore, a presentation attack detection (PAD) method is required to enhance the security level of face recognition systems. Most of the previously proposed PAD methods for face recognition systems have focused on using handcrafted image features, which are designed by expert knowledge of designers, such as Gabor filter, local binary pattern (LBP), local ternary pattern (LTP), and histogram of oriented gradients (HOG). As a result, the extracted features reflect limited aspects of the problem, yielding a detection accuracy that is low and varies with the characteristics of presentation attack face images. The deep learning method has been developed in the computer vision research community, which is proven to be suitable for automatically training a feature extractor that can be used to enhance the ability of handcrafted features. To overcome the limitations of previously proposed PAD methods, we propose a new PAD method that uses a combination of deep and handcrafted features extracted from the images by visible-light camera sensor. Our proposed method uses the convolutional neural network (CNN) method to extract deep image features and the multi-level local binary pattern (MLBP) method to extract skin detail features from face images to discriminate the real and presentation attack face images. By combining the two types of image features, we form a new type of image features, called hybrid features, which has stronger discrimination ability than single image features. Finally, we use the support vector machine (SVM) method to classify the image features into real or presentation attack class. Our experimental results indicate that our proposed method outperforms previous PAD methods by yielding the smallest error rates on the same image databases. PMID:29495417

  16. A combination of small bowel imaging methods: conventional enteroclysis with complementary magnetic resonance enteroclysis

    Energy Technology Data Exchange (ETDEWEB)

    Akman, C. [Department of Radiology, Cerrahpasa Medical Faculty, Istanbul University, Istanbul (Turkey); Korman, U. [Department of Radiology, Cerrahpasa Medical Faculty, Istanbul University, Istanbul (Turkey)]. E-mail: ugurk9@istanbul.edu.tr; Oguet, G. [Department of Radiology, Cerrahpasa Medical Faculty, Istanbul University, Istanbul (Turkey); Kurugoglu, S. [Department of Radiology, Cerrahpasa Medical Faculty, Istanbul University, Istanbul (Turkey); Urger, E. [Department of Radiology, Cerrahpasa Medical Faculty, Istanbul University, Istanbul (Turkey); Ulus, S. [Department of Radiology, Cerrahpasa Medical Faculty, Istanbul University, Istanbul (Turkey); Esen, G. [Department of Radiology, Cerrahpasa Medical Faculty, Istanbul University, Istanbul (Turkey); Tasci, I. [Department of Surgery, Cerrahpasa Medical Faculty, Istanbul University, Istanbul (Turkey)

    2005-07-01

    AIM: The aim of this prospective study was to evaluate the overall findings of conventional enteroclysis (CE) with complementary magnetic resonance enteroclysis (MRE) in small bowel disease. METHODS: The study included 32 patients referred from various clinical departments, with known or suspected small bowel disease and abnormalities on CE. Immediately after CE, true fast imaging with steady-state precession (true FISP), and unenhanced and gadolinium-enhanced T1-weighted fast low-angle shot (FLASH) sequences with fat saturation were obtained. Mucosal, mural and luminal changes of the small bowel were evaluated by each technique. In addition, bowel wall thickening, bowel wall enhancement and perienteric changes were assessed by MRE. The radiological findings obtained were evaluated together as a combination, and the role of MRE in the determination of the activity and complications of the small bowel disease was assessed. Radiological findings were correlated with clinical evaluation and follow-up in all cases, including endoscopy in 14 cases and surgery in 5 cases. RESULTS: MRE provided important supplementary mural and extramural information, including degree of pathological wall thickness, mural enhancement pattern associated with disease activity, perivisceral collection, abscess formation, mesenteric fibrofatty proliferation, lymphadenopathy and increase in perienteric vascularity. Short strictures were not revealed on MRE; however, for patients with a history of abdominal malignancy, MRE helped characterize the level of any obstruction and the extent of the disease. CONCLUSION: We recommend MRE for patients who have findings of advanced inflammatory bowel disease or neoplasm on CE examination. The combination of these two techniques can provide important information on the degree and extent of the disorder.

  17. Semi-supervised change detection approach combining sparse fusion and constrained k means for multi-temporal remote sensing images

    Directory of Open Access Journals (Sweden)

    Anisha M. Lal

    2015-12-01

    Full Text Available Change detection is the measure of the thematic change information that can guide to more tangible insights into an underlying process involving land cover, land usage and environmental changes. This paper deals with a semi-supervised change detection approach combining sparse fusion and constrained k means clustering on multi-temporal remote sensing images taken at different timings T1 and T2. Initially a remote sensing fusion method with sparse representation over learned dictionaries is applied to the difference images. The dictionaries are learned from the difference images adaptively. The fused image is calculated by combining the sparse coefficients and the dictionary. Finally the fused image is subjected to constrained k means (CKM clustering combining few known labelled patterns and unlabelled patterns which have been collected from experts. The enhanced (CKM approach (ECKM is compared with k means, adaptive k means (AKM and fuzzy c means (FCM. Experimental results were carried out on multi-temporal remote sensing images. Results obtained using PCC and F1 measure confirms the effectiveness of the proposed approach. It is also noticed that the ECKM provides better results with less misclassification of errors as compared to k means, adaptive k means and fuzzy c means.

  18. Thermodynamics of ultracold Fermi gases

    International Nuclear Information System (INIS)

    Nascimbene, Sylvain

    2010-01-01

    Complex Hamiltonians from condensed matter, such as the Fermi-Hubbard model, can be experimentally studied using ultracold gases. This thesis describes a new method for determining the equation of state of an ultracold gas, making the comparison with many-body theories straightforward. It is based on the measurement of the local pressure inside a trapped gas from the analysis of its in situ image. We first apply this method to the study of a Fermi gas with resonant interactions, a weakly-interacting 7 Li gas acting as a thermometer. Surprisingly, none of the existing many-body theories of the unitary gas accounts for the equation of state deduced from our study over its full range. The virial expansion extracted from the high-temperature data agrees with the resolution of the three-body problem. At low temperature, we observe, contrary to some previous studies, that the normal phase behaves as a Fermi liquid. Finally we obtain the critical temperature for superfluidity from a clear signature on the equation of state. We also measure the pressure of the ground state as a function of spin imbalance and interaction strength - measure directly relevant to describe the crust of neutron stars. Our data validate Monte-Carlo simulations and quantify the Lee-Huang-Yang corrections to mean-field interactions in low-density fermionic or bosonic superfluids. We show that, in most cases, the partially polarized normal phase can be described as a Fermi liquid of polarons. The polaron effective mass extracted from the equation of state is in agreement with a study of collective modes. (author)

  19. Greenhouse gases and global warming

    International Nuclear Information System (INIS)

    1995-01-01

    From previous articles we have learned about the complexities of our environment, its atmosphere and its climate system. we have also learned that climate change and, therefore global warm and cool periods are naturally occurring phenomena. Moreover, all scientific evidence suggests that global warming, are likely to occur again naturally in the future. However, we have not yet considered the role of the rates of climate change in affecting the biosphere. It appears that how quickly the climate changes may be more important than the change itself. In light of this concern, let us now consider the possibility that, is due to human activity. We may over the next century experience global warming at rates and magnitudes unparalleled in recent geologic history. The following questions are answered; What can we learn from past climates? What do we know about global climates over the past 100 years? What causes temperature change? What are the greenhouse gases? How much have concentration of greenhouse gases increased in recent years? Why are increases in concentrations of greenhouse of concern? What is the e nhanced greenhouse effect ? How can human activity impact the global climate? What are some reasons for increased concentrations of greenhouse gases? What are fossil fuel and how do they transform into greenhouse gases? Who are the biggest emitters of greenhouse gases? Why are canada per capita emissions of greenhouse gases relatively high? (Author)

  20. Wire chamber gases

    International Nuclear Information System (INIS)

    Va'vra, J.

    1992-04-01

    In this paper, we describe new developments in gas mixtures which have occurred during the last 3--4 years. In particular, we discuss new results on the measurement and modeling of electron drift parameters, the modeling of drift chamber resolution, measurements of primary ionization and the choice of gas for applications such as tracking, single electron detection, X-ray detection and visual imaging. In addition, new results are presented on photon feedback, breakdown and wire aging

  1. Combined Diffusion Tensor Imaging and Apparent Transverse Relaxation Rate Differentiate Parkinson Disease and Atypical Parkinsonism.

    Science.gov (United States)

    Du, G; Lewis, M M; Kanekar, S; Sterling, N W; He, L; Kong, L; Li, R; Huang, X

    2017-05-01

    Both diffusion tensor imaging and the apparent transverse relaxation rate have shown promise in differentiating Parkinson disease from atypical parkinsonism (particularly multiple system atrophy and progressive supranuclear palsy). The objective of the study was to assess the ability of DTI, the apparent transverse relaxation rate, and their combination for differentiating Parkinson disease, multiple system atrophy, progressive supranuclear palsy, and controls. A total of 106 subjects (36 controls, 35 patients with Parkinson disease, 16 with multiple system atrophy, and 19 with progressive supranuclear palsy) were included. DTI and the apparent transverse relaxation rate measures from the striatal, midbrain, limbic, and cerebellar regions were obtained and compared among groups. The discrimination performance of DTI and the apparent transverse relaxation rate among groups was assessed by using Elastic-Net machine learning and receiver operating characteristic curve analysis. Compared with controls, patients with Parkinson disease showed significant apparent transverse relaxation rate differences in the red nucleus. Compared to those with Parkinson disease, patients with both multiple system atrophy and progressive supranuclear palsy showed more widespread changes, extending from the midbrain to striatal and cerebellar structures. The pattern of changes, however, was different between the 2 groups. For instance, patients with multiple system atrophy showed decreased fractional anisotropy and an increased apparent transverse relaxation rate in the subthalamic nucleus, whereas patients with progressive supranuclear palsy showed an increased mean diffusivity in the hippocampus. Combined, DTI and the apparent transverse relaxation rate were significantly better than DTI or the apparent transverse relaxation rate alone in separating controls from those with Parkinson disease/multiple system atrophy/progressive supranuclear palsy; controls from those with Parkinson

  2. Multifunctional gold nanostar conjugates for tumor imaging and combined photothermal and chemo-therapy.

    Science.gov (United States)

    Chen, Haiyan; Zhang, Xin; Dai, Shuhang; Ma, Yuxiang; Cui, Sisi; Achilefu, Samuel; Gu, Yueqing

    2013-01-01

    Uniform gold nanostars (Au NS) were conjugated with cyclic RGD (cRGD) and near infrared (NIR) fluorescence probe (MPA) or anti-cancer drug (DOX) to obtain multi-functional nanoconstructs, Au-cRGD-MPA and Au-cRGD-DOX respectively. The NIR contrast agent Au-cRGD-MPA was shown to have low cytotoxicity. Using tumor cells and tumor bearing mice, these imaging nanoparticles demonstrated favorable tumor-targeting capability mediated by RGD peptide binding to its over-expressed receptor on the tumor cells. The multi-therapeutic analogue, Au-cRGD-DOX, integrates targeting tumor, chemotherapy and photo-thermotherapy into a single system. The synergistic effect of photo-thermal therapy and chemotherapy was demonstrated in different tumor cell lines and in vivo using S180 tumor-bearing mouse models. The viability of MDA-MB-231 cells was only 40 % after incubation with Au-cRGD-DOX and irradiation with NIR light. Both tail vein and intratumoral injections showed Au-cRGD-DOX treated mice exhibiting the slowest tumor increase. These results indicate that the multifunctional nanoconstruct is a promising combined therapeutic agent for tumor-targeting treatment, with the potential to enhance the anti-cancer treatment outcomes.

  3. Aerial ungulate surveys with a combination of infrared and high–resolution natural colour images

    Directory of Open Access Journals (Sweden)

    Franke, U.

    2012-01-01

    Full Text Available Information on animal population sizes is crucial for wildlife management. In aerial surveys, we used a silent light aircraft (microlight and a combination of a computer–linked thermal infrared camera (640 x 480 pixels to detect ungulates and high–resolution visual images (5,616 x 3,744 pixels to identify specific species. From winter 2008/2009 to winter 2010/2011, we flew 48 missions over three German national parks and a German/ French biosphere reserve. Within each study area, we followed non–overlapping linear transects with a flying altitude ~450 m above ground level and scanned 1,500–2,000 ha every two hours of flight time. Animals best detected and identified were red deer and fallow deer. Detection rates with respect to the type and density of vegetation cover ranged from 0% (young spruce to 75% (young defoliated beech to 100% (open land. This non–invasive method is cost–effective and suitable for many landscapes.

  4. Practical waveform inversion in anisotropic media: The natural combination of the data and image objectives

    KAUST Repository

    Alkhalifah, Tariq Ali

    2016-09-06

    Addressing anisotropy in full wavenumber inversion (FWI) is crucial to obtaining credible models, and it is extremely challenging considering the multi parameter nature of the inversion. A successful FWI in anisotropic media takes into account the sensitivity of the data (or the wave) to the long and short wavelength components of the anisotropic parameters. Considering the low sensitivity of FWI to the anellipticity parameter ? when parametrizing the acoustic transversely isotropic model with the horizontal velocity, η and ε, we develop a combined FWI and reflection waveform inversion (RWI) to invert for the anisotropic parameters that influence surface seismic data. This practical waveform inversion (PWI) separates the parameters to their resolvable scales, with information accessed from the data fitting (FWI) and the image focusing (RWI) objectives. With this parametrization, the RWI role is to obtain a smooth ηmodel, as well as velocity, while FWI focusses on the scattering potential of the horizontal velocity. The parameter η is used to produce the Born scattered wavefield for the RWI part and eventually fit the amplitude for the imperfect physics in the FWI part.

  5. Combining high-resolution satellite images and altimetry to estimate the volume of small lakes

    Science.gov (United States)

    Baup, F.; Frappart, F.; Maubant, J.

    2014-05-01

    This study presents an approach to determining the volume of water in small lakes (manager of the lake. Three independent approaches are developed to estimate the lake volume and its temporal variability. The first two approaches (HRBV and ABV) are empirical and use synchronous ground measurements of the water volume and the satellite data. The results demonstrate that altimetry and imagery can be effectively and accurately used to monitor the temporal variations of the lake (R2ABV = 0.98, RMSEABV = 5%, R2HRBV = 0.90, and RMSEABV = 7.4%), assuming a time-varying triangular shape for the shore slope of the lake (this form is well adapted since it implies a difference inferior to 2% between the theoretical volume of the lake and the one estimated from bathymetry). The third method (AHRBVC) combines altimetry (to measure the lake level) and satellite images (of the lake surface) to estimate the volume changes of the lake and produces the best results (R2AHRBVC = 0.98) of the three methods, demonstrating the potential of future Sentinel and SWOT missions to monitor small lakes and reservoirs for agricultural and irrigation applications.

  6. Combined magnetic resonance coronary artery imaging, myocardial perfusion and late gadolinium enhancement in patients with suspected coronary artery disease

    Directory of Open Access Journals (Sweden)

    Dreysse Stephan

    2008-10-01

    Full Text Available Abstract Background Cardiovascular Magnetic Resonance (CMR imaging offers methods for the detection of ischemia and myocardial infarction as well as visualization of the coronary arteries (MRCA. However, a direct comparison of adenosine perfusion (PERF, late gadolinium enhancement (LGE and MRCA or the results of their combination has not been performed. Aim of the study was to evaluate the feasibility/diagnostic performance of rest/stress perfusion, late gadolinium enhancement and MRCA and their combination in patients with suspected coronary artery disease (CAD in comparison to invasive angiography. Methods Fifty-four patients (60 ± 10 years, 35 men, CAD 48% underwent CMR including MRCA (steady state free precession, navigator whole heart approach, spatial resolution 0.7 × 0.7 × .0.9 mm, trigger delay and temporal resolution adjusted individually, stress PERF (adenosine 140 μg/min/kg, rest PERF (SSFP, 3 short axis, 1 saturation prepulse per slice and LGE (3D inversion recovery technique using Gd-BOPTA. Images were analyzed visually. Stenosis >50% in invasive angiography was considered significant. Results Mean study time was 68 ± 11 minutes. Sensitivity for PERF, LGE, MRCA and the combination of PERF/LGE and PERF/LGE/MRCA was 87%, 50%, 91%, 88% and 92%, respectively and specificity 88%, 96%, 46%, 88% and 56%, respectively. If image quality of MRCA was excellent (n = 18 the combination of MRCA/PERF/LGE yield a sensitivity of 86% and specificity of 91%. However, no test or combination improved diagnostic performance significantly compared to PERF alone. Conclusion In patients with CAD, the combination of stress PERF, LGE and MRCA is feasible. When compared to invasive angiography, adenosine stress perfusion outperforms CMR coronary angiography in direct comparison and yields the best results with non-significant improvement in combination with LGE and significant deterioration in combination with MRCA. MRCA may be of additional value only in

  7. A high-frequency ultrasound imaging system combining limited-angle spatial compounding and model-based synthetic aperture focusing.

    Science.gov (United States)

    Opretzka, Jörn; Vogt, Michael; Ermert, Helmut

    2011-07-01

    High-frequency ultrasound (HFUS) imaging systems are routinely used for medical diagnostics (skin, eyes) and for medical research (small animal imaging). Although systems with array transducers are already commercially available, imaging systems with single-element transducers are still of interest and available as well, because this type of transducer is less complex, less expensive, and technically mature. Nevertheless, drawbacks exist, for example, the need for mechanical scanning units and the limited depth of field. In this paper, we present a high-frequency (20 MHz) ultrasound imaging system equipped with a spherically focused transducer. Limited-angle spatial compounding is utilized to improve the image contrast, to suppress speckle and noise, and to reduce imaging artifacts. To overcome the limitation in depth of field, the system uses a novel synthetic aperture focusing technique based on the correlation of the recorded echo signals with the simulated point spread function of the imaging system. This method results in lower side lobe levels and greater noise reduction compared with delay-and-sum focusing, which is demonstrated by wire phantom measurements. When used in combination with limited-angle spatial compounding, as presented in this paper, the resulting image quality is superior to conventional single-element HFUS imaging systems and to array systems. Examples of measurements on tissue phantoms and small animals (ex vivo) are presented and discussed in detail.

  8. [Combination of radiological and nuclear medical imaging in animals: an overview about today's possibilities

    NARCIS (Netherlands)

    Behe, M.; Keil, B.; Alfke, H.; Bohm, I.; Kiessling, A.; Gotthardt, M.; Heverhagen, J.T.

    2007-01-01

    Molecular imaging of small animals has made considerable progress in the last years. Various research fields are interested in imaging small animals due to the lower numbers of animals per experiment. This has advantages with respect to financial, ethical and research aspects. Non-invasive imaging

  9. Drug quantification in turbid media by fluorescence imaging combined with light-absorption correction using white Monte Carlo simulations

    DEFF Research Database (Denmark)

    Xie, Haiyan; Liu, Haichun; Svenmarker, Pontus

    2011-01-01

    in vivo by the fluorescence imaging technique. In this paper we present a novel approach to compensate for the light absorption in homogeneous turbid media both for the excitation and emission light, utilizing time-resolved fluorescence white Monte Carlo simulations combined with the Beer-Lambert law...

  10. Improving the prediction of overall survival for head and neck cancer patients using image biomarkers in combination with clinical parameters

    NARCIS (Netherlands)

    Zhai, Tian-Tian; van Dijk, Lisanne V; Huang, Bao-Tian; Lin, Zhi-Xiong; Ribeiro, Cássia O; Brouwer, Charlotte L; Oosting, Sjoukje F; Halmos, Gyorgy B; Witjes, Max J H; Langendijk, Johannes A; Steenbakkers, Roel J H M; Sijtsema, Nanna M

    Purpose: To develop and validate prediction models of overall survival (OS) for head and neck cancer (HNC) patients based on image biomarkers (IBMs) of the primary tumor and positive lymph nodes (Ln) in combination with clinical parameters. Material and methods: The study cohort was composed of 289

  11. Radioactive gases monitor system: tritium, radon, noble gases

    International Nuclear Information System (INIS)

    Egey, J.Z.; Matatagui, E.

    2015-01-01

    A system for monitoring the radioactive gases tritium, radon and noble gases is described. We present the description of the sensor and the associated electronics that have been developed to monitor the presence of radioactive gases in air or other gaseous effluents. The system has a high sensitivity and a wide range of operation. The sensor is an ionization chamber, featuring the internal circulation of the gas to monitor and the associated electronics has a resolution better than 10 E-15A (fA). It allows the detection of the individual pulses that are produced during the alpha decay of radon and its daughter elements. The measurement system is made up of a commercial data acquisition system connected to a computer. The acquired data is presented on a graphical display and it is stored for later processing and analysis. We have a system that is of simple construction and versatile. Here we present the experimental results. (authors) [es

  12. THE IMAGE REGISTRATION OF FOURIER-MELLIN BASED ON THE COMBINATION OF PROJECTION AND GRADIENT PREPROCESSING

    Directory of Open Access Journals (Sweden)

    D. Gao

    2017-09-01

    Full Text Available Image registration is one of the most important applications in the field of image processing. The method of Fourier Merlin transform, which has the advantages of high precision and good robustness to change in light and shade, partial blocking, noise influence and so on, is widely used. However, not only this method can’t obtain the unique mutual power pulse function for non-parallel image pairs, even part of image pairs also can’t get the mutual power function pulse. In this paper, an image registration method based on Fourier-Mellin transformation in the view of projection-gradient preprocessing is proposed. According to the projection conformational equation, the method calculates the matrix of image projection transformation to correct the tilt image; then, gradient preprocessing and Fourier-Mellin transformation are performed on the corrected image to obtain the registration parameters. Eventually, the experiment results show that the method makes the image registration of Fourier-Mellin transformation not only applicable to the registration of the parallel image pairs, but also to the registration of non-parallel image pairs. What’s more, the better registration effect can be obtained

  13. The Image Registration of Fourier-Mellin Based on the Combination of Projection and Gradient Preprocessing

    Science.gov (United States)

    Gao, D.; Zhao, X.; Pan, X.

    2017-09-01

    Image registration is one of the most important applications in the field of image processing. The method of Fourier Merlin transform, which has the advantages of high precision and good robustness to change in light and shade, partial blocking, noise influence and so on, is widely used. However, not only this method can't obtain the unique mutual power pulse function for non-parallel image pairs, even part of image pairs also can't get the mutual power function pulse. In this paper, an image registration method based on Fourier-Mellin transformation in the view of projection-gradient preprocessing is proposed. According to the projection conformational equation, the method calculates the matrix of image projection transformation to correct the tilt image; then, gradient preprocessing and Fourier-Mellin transformation are performed on the corrected image to obtain the registration parameters. Eventually, the experiment results show that the method makes the image registration of Fourier-Mellin transformation not only applicable to the registration of the parallel image pairs, but also to the registration of non-parallel image pairs. What's more, the better registration effect can be obtained

  14. A novel liquid-Xenon detector concept for combined fast-neutrons and gamma imaging and spectroscopy

    International Nuclear Information System (INIS)

    Breskin, A; Israelashvili, I; Arazi, L; Shchemelinin, S; Chechik, R; Cortesi, M; Dangendorf, V; Bromberger, B; Vartsky, D

    2012-01-01

    A new detector concept is presented for combined imaging and spectroscopy of fast-neutrons and gamma rays. It comprises a liquid-Xenon (LXe) converter and scintillator coupled to a UV-sensitive gaseous imaging photomultiplier (GPM). Radiation imaging is obtained by localization of the scintillation-light from LXe with the position-sensitive GPM. The latter comprises a cascade of Thick Gas Electron Multipliers (THGEM), where the first element is coated with a CsI UV-photocathode. We present the concept and provide first model-simulation results of the processes involved and the expected performances of a detector having a LXe-filled capillaries converter. The new detector concept has potential applications in combined fast-neutron and gamma-ray screening of hidden explosives and fissile materials with pulsed sources.

  15. Experimental setup combining digital holographic microscopy (DHM) and fluorescence imaging to study gold nanoparticle mediated laser manipulation

    Science.gov (United States)

    Antonopoulos, Georgios C.; Rakoski, Mirko S.; Steltner, Benjamin; Kalies, Stefan; Ripken, Tammo; Meyer, Heiko

    2015-03-01

    Our research combines Digital Holographic Microscopy (DHM) and ˛uorescence microscopy to study the basic mechanisms of gold nanoparticle mediated laser manipulation. Herein we describe the technical aspects of the setup and holographic image reconstruction. Furthermore, results pertaining to cell volume change and calcium response of cells in laser manipulation will be presented and discussed. For the reconstruction of phase images from fringe image data, a phase unwrapping algorithm is presented that shows great potential to cope with the vast amount of data that was captured. This algorithm is a hybrid between a tile unwrapping technique and a path following unwrapper. It combines the robustness of a path following algorithm and a parallelizable tile unwrapping preprocessing step. The experimental setup enables simultaneous acquisition of ˛uorescence and phase images. For cell manipulation, a picosecond laser was coupled into the setup and weakly focused on cells incubated with gold nanoparticles. To study the cell volume change in the ˝rst minute, phase images were captured with a frame rate of 33 fps. Fluorescence images yielded the calcium signal of the cells as well as the dynamics of the F-actin cytoskeleton after irradiation. The setup is suitable to study fast changes in biophysical and morphological para

  16. A Geochemical Approach for Monitoring a CO2 Pilot Site: Rousse, France. A Major gases, CO2-Carbon Isotopes and Noble Gases Combined Approach Une méthode géochimique pour la surveillance d’un site pilote de stockage de CO2 : Rousse, France. Approche combinant les gaz majeurs, l’isotopie du carbone du CO2 et les gaz rares

    Directory of Open Access Journals (Sweden)

    Garcia B.

    2012-02-01

    Full Text Available This paper presents the geochemical characterization of various gas end-members involved in a depleted gas field CO2 storage pilot (Rousse, France. In this pilot, CO2 is produced by oxycombustion from natural gas transformed into fuel gas at the Lacq plant, and transported in a pipeline 30 km away to the depleted gas reservoir of Rousse. Gases produced at Rousse before CO2 injection, the Lacq fuel gas and the CO2 resulting from the oxy-fuel combustion were sampled, together with gases from a –45 m monitoring well and from soils in the vicinity of the Rousse structure. For all samples, the bulk gas composition, the carbon isotopic compositions and the abundance and isotopic signatures of the noble gases were determined. The bulk gas compositions of the Rousse natural gas are comparable to the Lacq fuel gas with methane as the main compound with residual C2-C5 and CO2. Soil gases are typical mixtures of air with biogenic CO2 (up to 9-10%, while the monitoring well gases display typical air compositions with no excess CO2 The Rousse gas and the Lacq fuel gas have δ13CCH4 values of –41.0‰ and –43.0‰ respectively. The injected CO2 out of the oxycombustion chamber has a δ13CCO2 of –40.0‰, whereas δ13CCO2 value for soils samples is comprised between –15 and –25‰. The Rousse natural gas and the Lacq fuel gas are both characterized by a high He enrichment, and depletion in Ne, Ar and Kr compared to the air values. The oxyfuel combustion process provides a CO2 with the He enrichment of the Lacq fuel gas, and a Ne, Ar and Kr composition reflecting that of the oxygen produced at the Air Separation Unit (ASU. Indeed, Ne is depleted relatively to the air, while Kr is enriched up to tenfold, which results from the cryogenic separation of the air noble gases within the ASU. Soil samples noble gas compositions are equivalent to that of the air. In the light of these results, the compositions of the various end-members involved in this CO2

  17. Gases and carbon in metals

    International Nuclear Information System (INIS)

    Jehn, H.; Fromm, E.; Hoerz, G.

    1978-01-01

    This issue is part of a series of data on 'gases and carbon in metals'. The present survey includes results from papers dealing with gases and carbon in actinides and recommends critically selected data for each element. Firstly data od binary systems are presented, starting with hydrogen and followed by carbon, nitrogen, oxygen, and rare gases. Within one metal-metalloid system the data are listed under topics such as solubility limit, dissociation pressure of compunds, vapour pressure of volatile oxides, thermodynamic data, diffusion, transport parameters (effective valence, heat of transport), permeation of gases through metals, gas adsorption and gas desorption kinetics, compound formation, precipitation kinetics, and property changes. Following the data on binary systems, the data of ternary systems are presented, beginning with systems which contain one metal and two gases or one gas and carbon and continuing with systems with two metals and one gas or carbon. Within a ternary system the topics are arranged in the same way as in binary systems. (HB) [de

  18. Sequential combination of k-t principle component analysis (PCA) and partial parallel imaging: k-t PCA GROWL.

    Science.gov (United States)

    Qi, Haikun; Huang, Feng; Zhou, Hongmei; Chen, Huijun

    2017-03-01

    k-t principle component analysis (k-t PCA) is a distinguished method for high spatiotemporal resolution dynamic MRI. To further improve the accuracy of k-t PCA, a combination with partial parallel imaging (PPI), k-t PCA/SENSE, has been tested. However, k-t PCA/SENSE suffers from long reconstruction time and limited improvement. This study aims to improve the combination of k-t PCA and PPI on both reconstruction speed and accuracy. A sequential combination scheme called k-t PCA GROWL (GRAPPA operator for wider readout line) was proposed. The GRAPPA operator was performed before k-t PCA to extend each readout line into a wider band, which improved the condition of the encoding matrix in the following k-t PCA reconstruction. k-t PCA GROWL was tested and compared with k-t PCA and k-t PCA/SENSE on cardiac imaging. k-t PCA GROWL consistently resulted in better image quality compared with k-t PCA/SENSE at high acceleration factors for both retrospectively and prospectively undersampled cardiac imaging, with a much lower computation cost. The improvement in image quality became greater with the increase of acceleration factor. By sequentially combining the GRAPPA operator and k-t PCA, the proposed k-t PCA GROWL method outperformed k-t PCA/SENSE in both reconstruction speed and accuracy, suggesting that k-t PCA GROWL is a better combination scheme than k-t PCA/SENSE. Magn Reson Med 77:1058-1067, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  19. Combining a thermal-imaging diagnostic with an existing imaging VISAR diagnostic at the National Ignition Facility (NIF)

    Energy Technology Data Exchange (ETDEWEB)

    Robert M. Malone; John R. Celesteb; Peter M. Celliers; Brent C. Froggeta; Robert L. Guyton; Morris I. Kaufman; Tony L. Lee; Brian J. MacGowan; Edmund W. Ng; Imants P. Reinbachs; Ronald B. Robinson; Lynn G. Seppala; Tom W. Tunnell; Phillip W. Watts

    2005-01-01

    Optical diagnostics are currently being designed to analyze high-energy density physics experiments at the National Ignition Facility (NIF). Two independent line-imaging Velocity Interferometer System for Any Reflector (VISAR) interferometers have been fielded to measure shock velocities, breakout times, and emission of targets having sizes of 1–5 mm. An 8-inch-diameter, fused silica triplet lens collects light at f/3 inside the 30-foot-diameter NIF vacuum chamber. VISAR recordings use a 659.5-nm probe laser. By adding a specially coated beam splitter to the interferometer table, light at wavelengths from 540 to 645 nm is spilt into a thermal-imaging diagnostic. Because fused silica lenses are used in the first triplet relay, the intermediate image planes for different wavelengths separate by considerable distances. A corrector lens on the interferometer table reunites these separated wavelength planes to provide a good image. Thermal imaging collects light at f/5 from a 2-mm object placed at Target Chamber Center (TCC). Streak cameras perform VISAR and thermal-imaging recording. All optical lenses are on kinematic mounts so that pointing accuracy of the optical axis may be checked. Counter-propagating laser beams (orange and red) are used to align both diagnostics. The red alignment laser is selected to be at the 50 percent reflection point of the beam splitter. This alignment laser is introduced at the recording streak cameras for both diagnostics and passes through this special beam splitter on its way into the NIF vacuum chamber.

  20. Combining a thermal-imaging diagnostic with an existing imaging VISAR diagnostic at the National Ignition Facility (NIF)

    Science.gov (United States)

    Malone, Robert M.; Celeste, John R.; Celliers, Peter M.; Frogget, Brent C.; Guyton, Robert L.; Kaufman, Morris I.; Lee, Tony L.; MacGowan, Brian J.; Ng, Edmund W.; Reinbachs, Imants P.; Robinson, Ronald B.; Seppala, Lynn G.; Tunnell, Thomas W.; Watts, Phillip W.

    2005-08-01

    Optical diagnostics are currently being designed to analyze high-energy density physics experiments at the National Ignition Facility (NIF). Two independent line-imaging Velocity Interferometer System for Any Reflector (VISAR) interferometers have been fielded to measure shock velocities, breakout times, and emission of targets having sizes of 1-5 mm. An 8-inch-diameter, fused silica triplet lens collects light at f/3 inside the 30-foot-diameter NIF vacuum chamber. VISAR recordings use a 659.5-nm probe laser. By adding a specially coated beam splitter to the interferometer table, light at wavelengths from 540 to 645 nm is spilt into a thermal-imaging diagnostic. Because fused silica lenses are used in the first triplet relay, the intermediate image planes for different wavelengths separate by considerable distances. A corrector lens on the interferometer table reunites these separated wavelength planes to provide a good image. Thermal imaging collects light at f/5 from a 2-mm object placed at Target Chamber Center (TCC). Streak cameras perform VISAR and thermal-imaging recording. All optical lenses are on kinematic mounts so that pointing accuracy of the optical axis may be checked. Counter-propagating laser beams (orange and red) are used to align both diagnostics. The red alignment laser is selected to be at the 50 percent reflection point of the beam splitter. This alignment laser is introduced at the recording streak cameras for both diagnostics and passes through this special beam splitter on its way into the NIF vacuum chamber.

  1. Independent slab-phase modulation combined with parallel imaging in bilateral breast MRI.

    Science.gov (United States)

    Han, Misung; Beatty, Philip J; Daniel, Bruce L; Hargreaves, Brian A

    2009-11-01

    Independent slab-phase modulation allows three-dimensional imaging of multiple volumes without encoding the space between volumes, thus reducing scan time. Parallel imaging further accelerates data acquisition by exploiting coil sensitivity differences between volumes. This work compared bilateral breast image quality from self-calibrated parallel imaging reconstruction methods such as modified sensitivity encoding, generalized autocalibrating partially parallel acquisitions and autocalibrated reconstruction for Cartesian sampling (ARC) for data with and without slab-phase modulation. A study showed an improvement of image quality by incorporating slab-phase modulation. Geometry factors measured from phantom images were more homogenous and lower on average when slab-phase modulation was used for both mSENSE and GRAPPA reconstructions. The resulting improved signal-to-noise ratio (SNR) was validated for in vivo images as well using ARC instead of GRAPPA, illustrating average SNR efficiency increases in mSENSE by 5% and ARC by 8% based on region of interest analysis. Furthermore, aliasing artifacts from mSENSE reconstruction were reduced when slab-phase modulation was used. Overall, slab-phase modulation with parallel imaging improved image quality and efficiency for 3D bilateral breast imaging. (c) 2009 Wiley-Liss, Inc.

  2. Person Recognition System Based on a Combination of Body Images from Visible Light and Thermal Cameras.

    Science.gov (United States)

    Nguyen, Dat Tien; Hong, Hyung Gil; Kim, Ki Wan; Park, Kang Ryoung

    2017-03-16

    The human body contains identity information that can be used for the person recognition (verification/recognition) problem. In this paper, we propose a person recognition method using the information extracted from body images. Our research is novel in the following three ways compared to previous studies. First, we use the images of human body for recognizing individuals. To overcome the limitations of previous studies on body-based person recognition that use only visible light images for recognition, we use human body images captured by two different kinds of camera, including a visible light camera and a thermal camera. The use of two different kinds of body image helps us to reduce the effects of noise, background, and variation in the appearance of a human body. Second, we apply a state-of-the art method, called convolutional neural network (CNN) among various available methods, for image features extraction in order to overcome the limitations of traditional hand-designed image feature extraction methods. Finally, with the extracted image features from body images, the recognition task is performed by measuring the distance between the input and enrolled samples. The experimental results show that the proposed method is efficient for enhancing recognition accuracy compared to systems that use only visible light or thermal images of the human body.

  3. Interactive, multi-modality image registrations for combined MRI/MRSI-planned HDR prostate brachytherapy

    Directory of Open Access Journals (Sweden)

    Galen Reed

    2011-03-01

    Full Text Available Purpose: This study presents the steps and criteria involved in the series of image registrations used clinically during the planning and dose delivery of focal high dose-rate (HDR brachytherapy of the prostate. Material and methods: Three imaging modalities – Magnetic Resonance Imaging (MRI, Magnetic Resonance Spectroscopic Imaging (MRSI, and Computed Tomography (CT – were used at different steps during the process. MRSI is used for identification of dominant intraprosatic lesions (DIL. A series of rigid and nonrigid transformations were applied to the data to correct for endorectal-coil-induced deformations and for alignment with the planning CT. Mutual information was calculated as a morphing metric. An inverse planning optimization algorithm was applied to boost dose to the DIL while providing protection to the urethra, penile bulb, rectum, and bladder. Six prostate cancer patients were treated using this protocol. Results: The morphing algorithm successfully modeled the probe-induced prostatic distortion. Mutual information calculated between the morphed images and images acquired without the endorectal probe showed a significant (p = 0.0071 increase to that calculated between the unmorphed images and images acquired without the endorectal probe. Both mutual information and visual inspection serve as effective diagnostics of image morphing. The entire procedure adds less than thirty minutes to the treatment planning. Conclusion: This work demonstrates the utility of image transformations and registrations to HDR brachytherapy of prostate cancer.

  4. Desulphurization of exhaust gases in chemical processes

    Energy Technology Data Exchange (ETDEWEB)

    Asperger, K.; Wischnewski, W.

    1981-01-01

    The sulfur content of exhaust gases can be reduced by: desulphurization of fuels; modification of processes; or treatment of resultant gases. In this paper a few selected examples from the chemical industry in the German Democratic Republic are presented. Using modified processes and treating the resultant gases, the sulphuric content of exhaust gases is effectively reduced. Methods to reduce the sulfur content of exhaust gases are described in the field of production of: sulphuric acid; viscose; fertilizers; and paraffin.

  5. ViRPET--combination of virtual reality and PET brain imaging

    Science.gov (United States)

    Majewski, Stanislaw; Brefczynski-Lewis, Julie

    2017-05-23

    Various methods, systems and apparatus are provided for brain imaging during virtual reality stimulation. In one example, among others, a system for virtual ambulatory environment brain imaging includes a mobile brain imager configured to obtain positron emission tomography (PET) scans of a subject in motion, and a virtual reality (VR) system configured to provide one or more stimuli to the subject during the PET scans. In another example, a method for virtual ambulatory environment brain imaging includes providing stimulation to a subject through a virtual reality (VR) system; and obtaining a positron emission tomography (PET) scan of the subject while moving in response to the stimulation from the VR system. The mobile brain imager can be positioned on the subject with an array of imaging photodetector modules distributed about the head of the subject.

  6. Image restoration technique using median filter combined with decision tree algorithm

    International Nuclear Information System (INIS)

    Sethu, D.; Assadi, H.M.; Hasson, F.N.; Hasson, N.N.

    2007-01-01

    Images are usually corrupted during transmission principally due to interface in the channel used for transmission. Images also be impaired by the addition of various forms of noise. Salt and pepper is commonly used to impair the image. Salt and pepper noise can be caused by errors in data transmission, malfunctioning pixel elements in camera sensors, and timing errors in the digitization process. During the filtering of noisy image, important features such as edges, lines and other fine image details embedded in the image tends to blur because of filtering operation. The enhancement of noisy data, however, is a very critical process because the sharpening operation can significantly increase the noise. In this respect, contrast enhancement is often necessary in order to highlight details that have been blurred. In this proposed approach we aim to develop image processing technique that can meet this new requirement, which are high quality and high speed. Furthermore, prevent the noise accretion during the sharpening of the image details, and compare the restored images via proposed method with other kinds of filters. (author)

  7. Combining semantic technologies with a content-based image retrieval system - Preliminary considerations

    Science.gov (United States)

    Chmiel, P.; Ganzha, M.; Jaworska, T.; Paprzycki, M.

    2017-10-01

    Nowadays, as a part of systematic growth of volume, and variety, of information that can be found on the Internet, we observe also dramatic increase in sizes of available image collections. There are many ways to help users browsing / selecting images of interest. One of popular approaches are Content-Based Image Retrieval (CBIR) systems, which allow users to search for images that match their interests, expressed in the form of images (query by example). However, we believe that image search and retrieval could take advantage of semantic technologies. We have decided to test this hypothesis. Specifically, on the basis of knowledge captured in the CBIR, we have developed a domain ontology of residential real estate (detached houses, in particular). This allows us to semantically represent each image (and its constitutive architectural elements) represented within the CBIR. The proposed ontology was extended to capture not only the elements resulting from image segmentation, but also "spatial relations" between them. As a result, a new approach to querying the image database (semantic querying) has materialized, thus extending capabilities of the developed system.

  8. Development of proportional counters using photosensitive gases and liquids

    International Nuclear Information System (INIS)

    Anderson, D.F.

    1984-10-01

    An introduction to the history and to the principle of operation of wire chambers using photosensitive gases and liquids is presented. Their use as light sensors coupled to Gas Scintillation Proportional Counters and BaF 2 , as well as their use in Cherenkov Ring imaging, is discussed in some detail. 42 references, 21 figures

  9. [CFC gases in medicinal sprays].

    Science.gov (United States)

    Pedersen, P H; Svendsen, U G

    1989-03-20

    In 1987, approximately 1.18 million aerosol dispensers for medicinal use were sold in Denmark. These contained approximately 29 tons of completely halogenized CFC gases ("Freon") and the preparations were employed for the treatment of bronchial asthma and rhinitis. The possibilities of substitutes are discussed in this article. Preparations are already available which do not contain CFC. Producers of CFC are also attempting to develop new aerosol gases which do not damage the environment. Perhaps these will be found in medicinal preparations in the future.

  10. An illustrated comparison of processing methods for MR phase imaging and QSM: combining array coil signals and phase unwrapping.

    Science.gov (United States)

    Robinson, Simon Daniel; Bredies, Kristian; Khabipova, Diana; Dymerska, Barbara; Marques, José P; Schweser, Ferdinand

    2017-04-01

    Phase imaging benefits from strong susceptibility effects at very high field and the high signal-to-noise ratio (SNR) afforded by multi-channel coils. Combining the information from coils is not trivial, however, as the phase that originates in local field effects (the source of interesting contrast) is modified by the inhomogeneous sensitivity of each coil. This has historically been addressed by referencing individual coil sensitivities to that of a volume coil, but alternative approaches are required for ultra-high field systems in which no such coil is available. An additional challenge in phase imaging is that the phase that develops up to the echo time is "wrapped" into a range of 2π radians. Phase wraps need to be removed in order to reveal the underlying phase distribution of interest. Beginning with a coil combination using a homogeneous reference volume coil - the Roemer approach - which can be applied at 3 T and lower field strengths, we review alternative methods for combining single-echo and multi-echo phase images where no such reference coil is available. These are applied to high-resolution data acquired at 7 T and their effectiveness assessed via an index of agreement between phase values over channels and the contrast-to-noise ratio in combined images. The virtual receiver coil and COMPOSER approaches were both found to be computationally efficient and effective. The main features of spatial and temporal phase unwrapping methods are reviewed, placing particular emphasis on recent developments in temporal phase unwrapping and Laplacian approaches. The features and performance of these are illustrated in application to simulated and high-resolution in vivo data. Temporal unwrapping was the fastest of the methods tested and the Laplacian the most robust in images with low SNR. © 2016 The Authors. NMR in Biomedicine published by John Wiley & Sons Ltd. © 2016 The Authors. NMR in Biomedicine published by John Wiley & Sons Ltd.

  11. MR imaging of the combined anterior and posterior cruciate ligament tears: focussing on the ratterns of injuries and associated findings

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Seon Young; Choi, Chang Lak; Park, Dal Soo; Park, Eun Hee; Lee, Sang Ho; Song, Mun Kab; Lee, Kwang Won [Eulji Medical College, Taejon (Korea, Republic of); Kwon, Soon Tae [Chungnam National Univ. College of Medicine, Taejon (Korea, Republic of)

    1997-09-01

    To evaluate the patterns of injuries and frequency of associated findings on MR imaging in patients with both anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL)tears;to compare the associated findings, as seen on MR imaging, in cases with both ACL and PCL tears with those with ACL or PCL tears. Ten patients with compbined ACL and PCL tears, 16 with ACL tears and 18 with PCL tears, all confirmed by arthroscopy or open surgery, were involved in this study. To identify the associated knee injuries, MR images were retrospectively evaluated. In ten patients with combined ACL and PCL tears, open surgery led to the identification of six complete ACL tears (60%), four partial ACL tears (40%), eitht complete PCL tears (80%) and two partial PCL tears (20%). Injuries associated with these combined tears, and revealed by MR imaging, comprised six medial collateral ligament injuries (60%), six lateral collateral ligament jnjuries (60%), five medial meniscal injuries (50%), three lateral meniscal injuries (30%), nine bony injuries (90%), two posterior capsular injuries (20%), and three popliteus muscle injuries (30%). The frequency of popliteus muscle injury was significantly different (p<0.05, Fisher's exact test) between the group with both ACL and PCL tears and that with ACL or PCL tears. Associated findings in patients with combined ACL and PCL tears are more frequent than in those with ACL or PCL tears. In cases involving combined ACL and PCL tears, associated findings-as seen on MR images-should thus be carefully examined.

  12. Combined X-ray CT and mass spectrometry for biomedical imaging applications

    NARCIS (Netherlands)

    Schioppa Jr, E.; Ellis, S.; Bruinen, A.L.; Visser, J.; Heeren, R.M.A.; Uher, J.; Koffeman, E.

    2014-01-01

    Imaging technologies play a key role in many branches of science, especially in biology and medicine. They provide an invaluable insight into both internal structure and processes within a broad range of samples. There are many techniques that allow one to obtain images of an object. Different

  13. Interpretation of cardiac wall motion from cine-MRI combined with parametric imaging based on the Hilbert transform.

    Science.gov (United States)

    Benameur, Narjes; Caiani, Enrico Gianluca; Arous, Younes; Abdallah, Nejmeddine Ben; Kraiem, Tarek

    2017-08-01

    The aim of this study was to test and validate the clinical impact of parametric amplitude images obtained using the Hilbert transform on the regional interpretation of cardiac wall motion abnormalities from cine-MR images by non-expert radiologists compared with expert consensus. Cine-MRI short-axis images obtained in 20 patients (10 with myocardial infarction, 5 with myocarditis and 5 with normal function) were processed to compute a parametric amplitude image for each using the Hilbert transform. Two expert radiologists blindly reviewed the cine-MR images to define a gold standard for wall motion interpretation for each left ventricular sector. Two non-expert radiologists reviewed and graded the same images without and in combination with parametric images. Grades assigned to each segment in the two separate sessions were compared with the gold standard. According to expert interpretation, 264/320 (82.5%) segments were classified as normal and 56/320 (17.5%) were considered abnormal. The accuracy of the non-expert radiologists' grades compared to the gold standard was significantly improved by adding parametric images (from 87.2 to 94.6%) together with sensitivity (from 64.29 to 84.4%) and specificity (from 92 to 96.9%), also resulting in reduced interobserver variability (from 12.8 to 5.6%). The use of parametric amplitude images based on the Hilbert transform in conjunction with cine-MRI was shown to be a promising technique for improvement of the detection of left ventricular wall motion abnormalities in less expert radiologists.

  14. Visually improved image compression by combining a conventional wavelet-codec with texture modeling.

    Science.gov (United States)

    Nadenau, Marcus J; Reichel, Julien; Kunt, Murat

    2002-01-01

    Human observers are very sensitive to a loss of image texture in photo-realistic images. For example a portrait image without the fine skin texture appears unnatural. Once the image is decomposed by a wavelet transformation, this texture is represented by many wavelet coefficients of low- and medium-amplitude. The conventional encoding of all these coefficients is very bitrate expensive. Instead, such an unstructured or stochastic texture can be modeled by a noise process and be characterized with very few parameters. Thus, a hybrid scheme can be designed that encodes the structural image information by a conventional wavelet codec and the stochastic texture in a model-based manner. Such a scheme, called WITCH (Wavelet-based Image/Texture Coding Hybrid), is proposed. It implements such an hybrid coding approach, while nevertheless preserving the features of progressive and lossless coding. Its low computational complexity and the parameter coding costs of only 0.01 bpp make it a valuable extension of conventional codecs. A comparison with the JPEG2000 image compression standard showed that the WITCH-scheme achieves the same subjective quality while increasing the compression ratio by more than a factor of two.

  15. CO-REGISTRATION AIRBORNE LIDAR POINT CLOUD DATA AND SYNCHRONOUS DIGITAL IMAGE REGISTRATION BASED ON COMBINED ADJUSTMENT

    Directory of Open Access Journals (Sweden)

    Z. H. Yang

    2016-06-01

    Full Text Available Aim at the problem of co-registration airborne laser point cloud data with the synchronous digital image, this paper proposed a registration method based on combined adjustment. By integrating tie point, point cloud data with elevation constraint pseudo observations, using the principle of least-squares adjustment to solve the corrections of exterior orientation elements of each image, high-precision registration results can be obtained. In order to ensure the reliability of the tie point, and the effectiveness of pseudo observations, this paper proposed a point cloud data constrain SIFT matching and optimizing method, can ensure that the tie points are located on flat terrain area. Experiments with the airborne laser point cloud data and its synchronous digital image, there are about 43 pixels error in image space using the original POS data. If only considering the bore-sight of POS system, there are still 1.3 pixels error in image space. The proposed method regards the corrections of the exterior orientation elements of each image as unknowns and the errors are reduced to 0.15 pixels.

  16. Bimodal imaging probes for combined PET and OI: recent developments and future directions for hybrid agent development.

    Science.gov (United States)

    Seibold, Uwe; Wängler, Björn; Schirrmacher, Ralf; Wängler, Carmen

    2014-01-01

    Molecular imaging--and especially positron emission tomography (PET)--has gained increasing importance for diagnosis of various diseases and thus experiences an increasing dissemination. Therefore, there is also a growing demand for highly affine PET tracers specifically accumulating and visualizing target structures in the human body. Beyond the development of agents suitable for PET alone, recent tendencies aim at the synthesis of bimodal imaging probes applicable in PET as well as optical imaging (OI), as this combination of modalities can provide clinical advantages. PET, due to the high tissue penetration of the γ-radiation emitted by PET nuclides, allows a quantitative imaging able to identify and visualize tumors and metastases in the whole body. OI on the contrary visualizes photons exhibiting only a limited tissue penetration but enables the identification of tumor margins and infected lymph nodes during surgery without bearing a radiation burden for the surgeon. Thus, there is an emerging interest in bimodal agents for PET and OI in order to exploit the potential of both imaging techniques for the imaging and treatment of tumor diseases. This short review summarizes the available hybrid probes developed for dual PET and OI and discusses future directions for hybrid agent development.

  17. A Non-invasive detection of lung cancer combined virtual gas sensors array with imaging recognition technique.

    Science.gov (United States)

    Chen, Xing; Cao, Mingfu; Hao, Yan; Li, Yi; Wang, Ping; Ying, Kejing; Pan, Hongming

    2005-01-01

    In this paper, we propose a non-invasive detection method of lung cancer combined with a sort of virtual SAW gas sensors array and imaging recognition method. A patient's breath goes through an electronic nose with solid phase micro extraction (SPME) and capillary column for pre-concentration and separation of volatile organic compounds (VOCs) respectively, a pair of SAW sensors one coated with a thin Poly-isobutylene (PIB) film is connected to the output of capillary column port for chemical compounds detection. A lung cancer tissues' culture medium study is also proposed for pathology validation. 11 VOCs which are considered as the biomarkers of lung cancer can be detected qualitatively and quantitatively. Finally these 11 VOCs are used to diagnose lung cancer patients in Run Run Shaw hospital by our e-nose with an improved artificial neural network (ANN) algorithm combined with imaging method for pattern recognition.

  18. Combination probe for optically assisted ultrasonic velocity-change imaging aimed at detecting unstable blood vessel plaque

    Science.gov (United States)

    Tanigawa, Shohei; Mano, Kazune; Wada, Kenji; Matsunaka, Toshiyuki; Horinaka, Hiromichi

    2016-04-01

    Blood vessel plaque with a large lipid core is at risk of becoming thrombus and is likely to induce acute heart disease. To prevent this, it is necessary to determine not only the plaque's size but also its chemical composition. We, therefore, made the prototype of a combination probe to diagnose carotid artery plaque. It is used to differentiate propagation characteristics between light spectra and ultrasonic images. By propagating light and ultrasound along a common direction, it is possible to effectively warm the diagnosis domain. Moreover, the probe is thought to be compact and be easy to use for diagnosing human carotid artery plaque. We applied the combination probe to a carotid artery phantom with a lipid area and obtained an image of the ultrasonic velocity change in the fatty area.

  19. Combination of radiological and nuclear medical imaging in animals: an overview about the today's possibilities

    International Nuclear Information System (INIS)

    Behe, M.; Keil, B.; Kiessling, A.; Heverhagen, J.T.; Alfke, H.; Boehm, I.; Gotthardt, M.

    2007-01-01

    Molecular imaging of small animals has made considerable progress in the last years. Various research fields are interested in imaging small animals due to the lower numbers of animals per experiment. This has advantages with respect to financial, ethical and research aspects. Non-invasive imaging allows examination of one animal several times during the same experiment. This makes it possible to follow a pathological process in the same animal over time. However, the radiological methods used such as magnetic resonance imaging or computed tomography as well as the nuclear medicine methods such as single photon emission computed tomography or positron emission tomography suffer from disadvantages. Molecular aspects are limited in the radiological methods while anatomical localization is difficult in nuclear medicine. The fusion of these methods leads to additional information. This review shows today's possibilities with their advantages as well as disadvantages. (orig.)

  20. Diagnostic accuracy of combined coronary angiography and adenosine stress myocardial perfusion imaging using 320-detector computed tomography: pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Nasis, Arthur; Ko, Brian S.; Leung, Michael C.; Antonis, Paul R.; Wong, Dennis T.; Kyi, Leo; Cameron, James D.; Meredith, Ian T.; Seneviratne, Sujith K. [Southern Health and Monash University, Monash Cardiovascular Research Centre, Monash Heart, Department of Medicine Monash Medical Centre (MMC), Melbourne (Australia); Nandurkar, Dee; Troupis, John M. [MMC, Southern Health, Department of Diagnostic Imaging, Melbourne (Australia)

    2013-07-15

    To determine the diagnostic accuracy of combined 320-detector row computed tomography coronary angiography (CTA) and adenosine stress CT myocardial perfusion imaging (CTP) in detecting perfusion abnormalities caused by obstructive coronary artery disease (CAD). Twenty patients with suspected CAD who underwent initial investigation with single-photon-emission computed tomography myocardial perfusion imaging (SPECT-MPI) were recruited and underwent prospectively-gated 320-detector CTA/CTP and invasive angiography. Two blinded cardiologists evaluated invasive angiography images quantitatively (QCA). A blinded nuclear physician analysed SPECT-MPI images for fixed and reversible perfusion defects. Two blinded cardiologists assessed CTA/CTP studies qualitatively. Vessels/territories with both >50 % stenosis on QCA and corresponding perfusion defect on SPECT-MPI were defined as ischaemic and formed the reference standard. All patients completed the CTA/CTP protocol with diagnostic image quality. Of 60 vessels/territories, 17 (28 %) were ischaemic according to QCA/SPECT-MPI criteria. Sensitivity, specificity, PPV, NPV and area under the ROC curve for CTA/CTP was 94 %, 98 %, 94 %, 98 % and 0.96 (P < 0.001) on a per-vessel/territory basis. Mean CTA/CTP radiation dose was 9.2 {+-} 7.4 mSv compared with 13.2 {+-} 2.2 mSv for SPECT-MPI (P < 0.001). Combined 320-detector CTA/CTP is accurate in identifying obstructive CAD causing perfusion abnormalities compared with combined QCA/SPECT-MPI, achieved with lower radiation dose than SPECT-MPI. (orig.)

  1. A novel technique combining laparoscopic and endovascular approaches using image fusion guidance for anterior embolization of type II endoleak

    OpenAIRE

    Zubair, M. Mujeeb; Chinnadurai, Ponraj; Loh, Francis E.; Loh, Thomas M.; Lumsden, Alan B.; Bechara, Carlos F.

    2016-01-01

    Type II endoleak (T2E) leading to aneurysm sac enlargement is one of the challenging complications associated with endovascular aneurysm repair. Recent guidelines recommend embolization of T2E associated with aneurysmal sac enlargement. Various percutaneous and endovascular techniques have been reported for embolization of T2E. We report a novel technique for T2E embolization combining laparoscopic and endovascular approaches using preoperative image fusion. We believe our technique provides ...

  2. Simultaneous hierarchical segmentation and vectorization of satellite images through combined data sampling and anisotropic triangulation

    Energy Technology Data Exchange (ETDEWEB)

    Grazzini, Jacopo [Los Alamos National Laboratory; Prasad, Lakshman [Los Alamos National Laboratory; Dillard, Scott [PNNL

    2010-10-21

    The automatic detection, recognition , and segmentation of object classes in remote sensed images is of crucial importance for scene interpretation and understanding. However, it is a difficult task because of the high variability of satellite data. Indeed, the observed scenes usually exhibit a high degree of complexity, where complexity refers to the large variety of pictorial representations of objects with the same semantic meaning and also to the extensive amount of available det.ails. Therefore, there is still a strong demand for robust techniques for automatic information extraction and interpretation of satellite images. In parallel, there is a growing interest in techniques that can extract vector features directly from such imagery. In this paper, we investigate the problem of automatic hierarchical segmentation and vectorization of multispectral satellite images. We propose a new algorithm composed of the following steps: (i) a non-uniform sampling scheme extracting most salient pixels in the image, (ii) an anisotropic triangulation constrained by the sampled pixels taking into account both strength and directionality of local structures present in the image, (iii) a polygonal grouping scheme merging, through techniques based on perceptual information , the obtained segments to a smaller quantity of superior vectorial objects. Besides its computational efficiency, this approach provides a meaningful polygonal representation for subsequent image analysis and/or interpretation.

  3. 3D imaging of cement-based materials at submicron resolution by combining laser scanning confocal microscopy with serial sectioning.

    Science.gov (United States)

    Yio, M H N; Mac, M J; Wong, H S; Buenfeld, N R

    2015-05-01

    In this paper, we present a new method to reconstruct large volumes of nontransparent porous materials at submicron resolution. The proposed method combines fluorescence laser scanning confocal microscopy with serial sectioning to produce a series of overlapping confocal z-stacks, which are then aligned and stitched based on phase correlation. The method can be extended in the XY plane to further increase the overall image volume. Resolution of the reconstructed image volume does not degrade with increase in sample size. We have used the method to image cementitious materials, hardened cement paste and concrete and the results obtained show that the method is reliable. Possible applications of the method such as three-dimensional characterization of the pores and microcracks in hardened concrete, three-dimensional particle shape characterization of cementitious materials and three-dimensional characterization of other porous materials such as rocks and bioceramics are discussed. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.

  4. Combined phase and X-Ray fluorescence imaging at the sub-cellular level

    International Nuclear Information System (INIS)

    Kosior, Ewelina

    2013-01-01

    This work presents some recent developments in the field of hard X-ray imaging applied to biomedical research. As the discipline is evolving quickly, new questions appear and the list of needs becomes bigger. Some of them are dealt with in this manuscript. It has been shown that the ID22NI beamline of the ESRF can serve as a proper experimental setup to investigate diverse aspects of cellular research. Together with its high spatial resolution, high flux and high energy range the experimental setup provides bigger field of view, is less sensitive to radiation damages (while taking phase contrast images) and suits well chemical analysis with emphasis on endogenous metals (Zn, Fe, Mn) but also with a possibility for exogenous one's like these found in nanoparticles (Au, Pt, Ag) study. Two synchrotron-based imaging techniques, fluorescence and phase contrast imaging were used in this research project. They were correlated with each other on a number of biological cases, from bacteria E.coli to various cells (HEK 293, PC12, MRC5VA, red blood cells). The explorations made in the chapter 5 allowed preparation of more established and detailed analysis, described in the next chapter where both techniques, X-ray fluorescence and phase contrast imaging, were exploited in order to access absolute metal projected mass fraction in a whole cell. The final image presents for the first time true quantitative information at the sub-cellular level, not biased by the cell thickness. Thus for the first time a fluorescence map serves as a complete quantitative image of a cell without any risk of misinterpretation. Once both maps are divided by each other pixel by pixel (fluorescence map divided by the phase map) they present a complete and final result of the metal (Zn in this work) projected mass fraction in ppm of dry weight. For the purpose of this calculation the analysis was extended to calibration (non-biological) samples. Polystyrene spheres of a known diameter and known

  5. Study on the ultrafast dynamics of o-xylene cation by combined fs-photoelectron imaging-photofragmentation spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yuzhu, E-mail: yuzhu.liu@psi.ch; Radi, Peter; Gerber, Thomas; Knopp, Gregor, E-mail: gregor.knopp@psi.ch

    2014-10-17

    Highlights: • Photoelectron imaging and photofragment spectroscopy are combined. • Photoelectron imaging has been measured to characterize the prepared cation states. • Ultrafast signal decay with time constant of 734 (±61) fs has been observed. - Abstract: Ultrafast dynamics of o-xylene cation has been studied by time resolved fs-photofragmentation (PF) spectroscopy in combination with photoelectron imaging (PEI). In the experiment, multiphoton ionization is used to prepare the o-xylene cation characterized by PEI. The ultrafast dynamics of o-xylene ions are measured by monitoring the time dependent parent-ion depletion and the fragment-ion formation, simultaneously. An ultrafast relaxation time of the parent ion of 734 (±61) fs has been observed. The PEI-PF measurements support the interpretation of this relaxation channel to a combination of internal conversion between the two ionic states (D{sub 0} and D{sub 1}) and intramolecular vibrational-energy redistribution process within the D{sub 0} state.

  6. Influence of Images on the Evaluation of Jams Using Conjoint Analysis Combined with Check-All-That-Apply (CATA) Questions.

    Science.gov (United States)

    Miraballes, Marcelo; Gámbaro, Adriana

    2018-01-01

    A study of the influence of the use of images in a conjoint analysis combined with check-all-that apply (CATA) questions on jams was carried out. The relative importance of flavor and the information presented in the label in the willingness to purchase and the perception of how healthy the product is has been evaluated. Sixty consumers evaluated the stimuli presented only in text format (session 1), and another group of 60 consumers did so by receiving the stimuli in text format along with an image of the product (session 2). In addition, for each stimulus, consumers answered a CATA question consisting of 20 terms related to their involvement with the product. The perception of healthy increased when the texts were accompanied with images and also increased when the text included information. Willingness to purchase was only influenced by the flavor of the jams. The presence of images did not influence the CATA question's choice of terms, which were influenced by the information presented in the text. The use of a check-all-that-apply question in concepts provided an interesting possibility when they were combined with the results from the conjoint analysis, improving the comprehension of consumers' perception. Using CATA questions as an alternative way of evaluating consumer involvement seems to be beneficial and should be evaluated much further. © 2017 Institute of Food Technologists®.

  7. Greenhouse effect of trace gases, 1970-1980

    Science.gov (United States)

    Lacis, A.; Hansen, J.; Lee, P.; Lebedeff, S.; Mitchell, T.

    1981-01-01

    Increased abundances were measured for several trace atmospheric gases in the decade 1970-1980. The equilibrium greenhouse warming for the measured increments of CH4, chlorofluorocarbons and N2O is between 50% and 100% of the equilibrium warming for the measured increase of atmospheric CO2 during the same 10 years. The combined warming of CO2 and trace gases should exceed natural global temperature variability in the 1980's and cause the global mean temperature to rise above the maximum of the late 1930's.

  8. Enhancement of noisy EDX HRSTEM spectrum-images by combination of filtering and PCA.

    Science.gov (United States)

    Potapov, Pavel; Longo, Paolo; Okunishi, Eiji

    2017-05-01

    STEM spectrum-imaging with collecting EDX signal is considered in view of the extraction of maximum information from very noisy data. It is emphasized that spectrum-images with weak EDX signal often suffer from information loss in the course of PCA treatment. The loss occurs when the level of random noise exceeds a certain threshold. Weighted PCA, though potentially helpful in isolation of meaningful variations from noise, might provoke the complete loss of information in the situation of weak EDX signal. Filtering datasets prior PCA can improve the situation and recover the lost information. In particular, Gaussian kernel filters are found to be efficient. A new filter useful in the case of sparse atomic-resolution EDX spectrum-images is suggested. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Digital staining for histopathology multispectral images by the combined application of spectral enhancement and spectral transformation.

    Science.gov (United States)

    Bautista, Pinky A; Yagi, Yukako

    2011-01-01

    In this paper we introduced a digital staining method for histopathology images captured with an n-band multispectral camera. The method consisted of two major processes: enhancement of the original spectral transmittance and the transformation of the enhanced transmittance to its target spectral configuration. Enhancement is accomplished by shifting the original transmittance with the scaled difference between the original transmittance and the transmittance estimated with m dominant principal component (PC) vectors;the m-PC vectors were determined from the transmittance samples of the background image. Transformation of the enhanced transmittance to the target spectral configuration was done using an nxn transformation matrix, which was derived by applying a least square method to the enhanced and target spectral training data samples of the different tissue components. Experimental results on the digital conversion of a hematoxylin and eosin (H&E) stained multispectral image to its Masson's trichrome stained (MT) equivalent shows the viability of the method.

  10. Combined fractional resurfacing (10600 nm/1540 nm): Tridimensional imaging evaluation of a new device for skin rejuvenation.

    Science.gov (United States)

    Mezzana, Paolo; Valeriani, Maurizio; Valeriani, Roberto

    2016-11-01

    In this study were described the results, by tridimensional imaging evaluation, of the new "Combined Fractional Resurfacing" technique with the first fractional laser that overtakes the limits of traditional ablative, nonablative fractional resurfacing by combining CO 2 ablative and GaAs nonablative lasers. These two wavelengths can work separately or in a mixed modality to give the best treatment choice to all the patients. In this study, it is demonstrated that the simultaneous combination of the CO 2 wavelength (10600 nm) and GaAs wavelength (1540 nm) reduced the downtime, reduced pain during the treatment, and produced better results on fine wrinkles reduction and almost the same results on pigmentation as seen with 3D analysis by Antera (Miravex).

  11. A combined post-mortem magnetic resonance imaging and quantitative histological study of multiple sclerosis pathology

    Science.gov (United States)

    Kolasinski, James; Chance, Steven A.; DeLuca, Gabriele C.; Esiri, Margaret M.; Chang, Eun-Hyuk; Palace, Jacqueline A.; McNab, Jennifer A.; Jenkinson, Mark; Miller, Karla L.; Johansen-Berg, Heidi

    2012-01-01

    Multiple sclerosis is a chronic inflammatory neurological condition characterized by focal and diffuse neurodegeneration and demyelination throughout the central nervous system. Factors influencing the progression of pathology are poorly understood. One hypothesis is that anatomical connectivity influences the spread of neurodegeneration. This predicts that measures of neurodegeneration will correlate most strongly between interconnected structures. However, such patterns have been difficult to quantify through post-mortem neuropathology or in vivo scanning alone. In this study, we used the complementary approaches of whole brain post-mortem magnetic resonance imaging and quantitative histology to assess patterns of multiple sclerosis pathology. Two thalamo-cortical projection systems were considered based on their distinct neuroanatomy and their documented involvement in multiple sclerosis: lateral geniculate nucleus to primary visual cortex and mediodorsal nucleus of the thalamus to prefrontal cortex. Within the anatomically distinct thalamo-cortical projection systems, magnetic resonance imaging derived cortical thickness was correlated significantly with both a measure of myelination in the connected tract and a measure of connected thalamic nucleus cell density. Such correlations did not exist between these markers of neurodegeneration across different thalamo-cortical systems. Magnetic resonance imaging lesion analysis depicted clearly demarcated subcortical lesions impinging on the white matter tracts of interest; however, quantitation of the extent of lesion-tract overlap failed to demonstrate any appreciable association with the severity of markers of diffuse pathology within each thalamo-cortical projection system. Diffusion-weighted magnetic resonance imaging metrics in both white matter tracts were correlated significantly with a histologically derived measure of tract myelination. These data demonstrate for the first time the relevance of functional

  12. Combination of panoramic and fluorescence endoscopic images to obtain tumor spatial distribution information useful for bladder cancer detection

    Science.gov (United States)

    Olijnyk, S.; Hernández Mier, Y.; Blondel, W. C. P. M.; Daul, C.; Wolf, D.; Bourg-Heckly, G.

    2007-07-01

    Bladder cancer is widely spread. Moreover, carcinoma in situ can be difficult to diagnose as it may be difficult to see, and become invasive in 50 % of case. Non invasive diagnosis methods like photodynamic or autofluorescence endoscopy allow enhancing sensitivity and specificity. Besides, bladder tumors can be multifocal. Multifocality increases the probability of recurrence and infiltration into bladder muscle. Analysis of spatial distribution of tumors could be used to improve diagnosis. We explore the feasibility to combine fluorescence and spatial information on phantoms. We developed a system allowing the acquisition of consecutive images under white light or UV excitation alternatively and automatically along the video sequence. We also developed an automatic image processing algorithm to build a partial panoramic image from a cystoscopic sequence of images. Fluorescence information is extracted from wavelength bandpass filtered images and superimposed over the cartography. Then, spatial distribution measures of fluorescent spots can be computed. This cartography can be positioned on a 3D generic shape of bladder by selecting some reference points. Our first results on phantoms show that it is possible to obtain cartography with fluorescent spots and extract quantitative information of their spatial distribution on a "wide" field of view basis.

  13. Nanocrystal clusters in combination with spectral imaging to improve sensitivity in antibody labeling applications of fluorescent nanocrystals

    Science.gov (United States)

    Maier, John S.; Panza, Janice L.; Bootman, Matt

    2007-02-01

    Composition-tunable nanocrystals are fluorescent nanoparticles with a uniform particle size and with adjustable optical characteristics. When used for optical labeling of biomolecular targets these and other nanotechnology solutions have enabled new approaches which are possible because of the high optical output, narrow spectral signal, consistent quantum efficiency across a broad emission range and long lived fluorescent behavior of the nanocrystals. When coupled with spectral imaging the full potential of multiplexing multiple probes in a complex matrix can be realized. Spectral imaging can be used to improve sensitivity of narrowband fluorophores through application of chemometric image processing techniques used to reduce the influence of autofluorescence background. Composition-tunable nanocrystals can be complexed together to form nanoclusters which have the advantage of significantly stronger signal and therefore a higher sensitivity. These nanoclusters can be targeted in biomolecular systems using standard live-cell labeling and immunohistochemistry based techniques. Composition-tunable nanocrystals and nanoclusters have comparable mass and brightness across a wide emission range. This enables the production of nanocrystal-based probes that have comparable reactivity and sensitivity over a large color range. We present spectral imaging results of antibody targeted nanocrystal cluster labeling of target proteins in cultured cells and a Western blot experiment. The combination of spectral imaging with the use of clusters of nanocrystals further improves the sensitivity over either of the approaches independently.

  14. Combining MRI with PET for partial volume correction improves image-derived input functions in mice

    International Nuclear Information System (INIS)

    Evans, Eleanor; Buonincontri, Guido; Izquierdo, David; Methner, Carmen; Hawkes, Rob C; Ansorge, Richard E; Kreig, Thomas; Carpenter, T Adrian; Sawiak, Stephen J

    2014-01-01

    Kinetic modelling in PET requires the arterial input function (AIF), defined as the time-activity curve (TAC) in plasma. This measure is challenging to obtain in mice due to low blood volumes, resulting in a reliance on image-based methods for AIF derivation. We present a comparison of PET- and MR-based region-of-interest (ROI) analysis to obtain image-derived AIFs from the left ventricle (LV) of a mouse model. ROI-based partial volume correction (PVC) was performed to improve quantification.

  15. Combining MRI with PET for partial volume correction improves image-derived input functions in mice

    Energy Technology Data Exchange (ETDEWEB)

    Evans, Eleanor; Buonincontri, Guido [Wolfson Brain Imaging Centre, University of Cambridge, Cambridge (United Kingdom); Izquierdo, David [Athinoula A Martinos Centre, Harvard University, Cambridge, MA (United States); Methner, Carmen [Department of Medicine, University of Cambridge, Cambridge (United Kingdom); Hawkes, Rob C [Wolfson Brain Imaging Centre, University of Cambridge, Cambridge (United Kingdom); Ansorge, Richard E [Department of Physics, University of Cambridge, Cambridge (United Kingdom); Kreig, Thomas [Department of Medicine, University of Cambridge, Cambridge (United Kingdom); Carpenter, T Adrian [Wolfson Brain Imaging Centre, University of Cambridge, Cambridge (United Kingdom); Sawiak, Stephen J [Wolfson Brain Imaging Centre, University of Cambridge, Cambridge (United Kingdom); Behavioural and Clinical Neurosciences Institute, University of Cambridge, Cambridge (United Kingdom)

    2014-07-29

    Kinetic modelling in PET requires the arterial input function (AIF), defined as the time-activity curve (TAC) in plasma. This measure is challenging to obtain in mice due to low blood volumes, resulting in a reliance on image-based methods for AIF derivation. We present a comparison of PET- and MR-based region-of-interest (ROI) analysis to obtain image-derived AIFs from the left ventricle (LV) of a mouse model. ROI-based partial volume correction (PVC) was performed to improve quantification.

  16. A photoacoustic tomography and ultrasound combined system for proximal interphalangeal joint imaging

    Science.gov (United States)

    Xu, Guan; Rajian, Justin R.; Girish, Gandikota; Wang, Xueding

    2013-03-01

    A photoacoustic (PA) and ultrasound (US) dual modality system for imaging human peripheral joints is introduced. The system utilizes a commercial US unit for both US control imaging and PA signal acquisition. Preliminary in vivo evaluation of the system on normal volunteers revealed that this system can recover both the structural and functional information of intra- and extra-articular tissues. Presenting both morphological and pathological information in joint, this system holds promise for diagnosis and characterization of inflammatory joint diseases such as rheumatoid arthritis.

  17. Soliton Gases and Generalized Hydrodynamics

    Science.gov (United States)

    Doyon, Benjamin; Yoshimura, Takato; Caux, Jean-Sébastien

    2018-01-01

    We show that the equations of generalized hydrodynamics (GHD), a hydrodynamic theory for integrable quantum systems at the Euler scale, emerge in full generality in a family of classical gases, which generalize the gas of hard rods. In this family, the particles, upon colliding, jump forward or backward by a distance that depends on their velocities, reminiscent of classical soliton scattering. This provides a "molecular dynamics" for GHD: a numerical solver which is efficient, flexible, and which applies to the presence of external force fields. GHD also describes the hydrodynamics of classical soliton gases. We identify the GHD of any quantum model with that of the gas of its solitonlike wave packets, thus providing a remarkable quantum-classical equivalence. The theory is directly applicable, for instance, to integrable quantum chains and to the Lieb-Liniger model realized in cold-atom experiments.

  18. Noble Gases in Lakes and Ground Waters

    OpenAIRE

    Kipfer, Rolf; Aeschbach-Hertig, Werner; Peeters, Frank; Stute, Marvin

    2002-01-01

    In contrast to most other fields of noble gas geochemistry that mostly regard atmospheric noble gases as 'contamination,' air-derived noble gases make up the far largest and hence most important contribution to the noble gas abundance in meteoric waters, such as lakes and ground waters. Atmospheric noble gases enter the meteoric water cycle by gas partitioning during air / water exchange with the atmosphere. In lakes and oceans noble gases are exchanged with the free atmosphere at the surface...

  19. [Rapid Identification of Epicarpium Citri Grandis via Infrared Spectroscopy and Fluorescence Spectrum Imaging Technology Combined with Neural Network].

    Science.gov (United States)

    Pan, Sha-sha; Huang, Fu-rong; Xiao, Chi; Xian, Rui-yi; Ma, Zhi-guo

    2015-10-01

    To explore rapid reliable methods for detection of Epicarpium citri grandis (ECG), the experiment using Fourier Transform Attenuated Total Reflection Infrared Spectroscopy (FTIR/ATR) and Fluorescence Spectrum Imaging Technology combined with Multilayer Perceptron (MLP) Neural Network pattern recognition, for the identification of ECG, and the two methods are compared. Infrared spectra and fluorescence spectral images of 118 samples, 81 ECG and 37 other kinds of ECG, are collected. According to the differences in tspectrum, the spectra data in the 550-1 800 cm(-1) wavenumber range and 400-720 nm wavelength are regarded as the study objects of discriminant analysis. Then principal component analysis (PCA) is applied to reduce the dimension of spectroscopic data of ECG and MLP Neural Network is used in combination to classify them. During the experiment were compared the effects of different methods of data preprocessing on the model: multiplicative scatter correction (MSC), standard normal variable correction (SNV), first-order derivative(FD), second-order derivative(SD) and Savitzky-Golay (SG). The results showed that: after the infrared spectra data via the Savitzky-Golay (SG) pretreatment through the MLP Neural Network with the hidden layer function as sigmoid, we can get the best discrimination of ECG, the correct percent of training set and testing set are both 100%. Using fluorescence spectral imaging technology, corrected by the multiple scattering (MSC) results in the pretreatment is the most ideal. After data preprocessing, the three layers of the MLP Neural Network of the hidden layer function as sigmoid function can get 100% correct percent of training set and 96.7% correct percent of testing set. It was shown that the FTIR/ATR and fluorescent spectral imaging technology combined with MLP Neural Network can be used for the identification study of ECG and has the advantages of rapid, reliable effect.

  20. Atmospheric Chemistry and Greenhouse Gases

    Energy Technology Data Exchange (ETDEWEB)

    Ehhalt, D.; Prather, M.; Dentener, F.; Derwent, R.; Dlugokencky, Edward J.; Holland, E.; Isaksen, I.; Katima, J.; Kirchhoff, V.; Matson, P.; Midgley, P.; Wang, M.; Berntsen, T.; Bey, I.; Brasseur, G.; Buja, L.; Collins, W. J.; Daniel, J. S.; DeMore, W. B.; Derek, N.; Dickerson, R.; Etheridge, D.; Feichter, J.; Fraser, P.; Friedl, R.; Fuglestvedt, J.; Gauss, M.; Grenfell, L.; Grubler, Arnulf; Harris, N.; Hauglustaine, D.; Horowitz, L.; Jackman, C.; Jacob, D.; Jaegle, L.; Jain, Atul K.; Kanakidou, M.; Karlsdottir, S.; Ko, M.; Kurylo, M.; Lawrence, M.; Logan, J. A.; Manning, M.; Mauzerall, D.; McConnell, J.; Mickley, L. J.; Montzka, S.; Muller, J. F.; Olivier, J.; Pickering, K.; Pitari, G.; Roelofs, G.-J.; Rogers, H.; Rognerud, B.; Smith, Steven J.; Solomon, S.; Staehelin, J.; Steele, P.; Stevenson, D. S.; Sundet, J.; Thompson, A.; van Weele, M.; von Kuhlmann, R.; Wang, Y.; Weisenstein, D. K.; Wigley, T. M.; Wild, O.; Wuebbles, D.J.; Yantosca, R.; Joos, Fortunat; McFarland, M.

    2001-10-01

    Chapter 4 of the IPCC Third Assessment Report Climate Change 2001: The Scientific Basis. Sections include: Executive Summary 2414.1 Introduction 2434.2 Trace Gases: Current Observations, Trends and Budgets 2484.3 Projections of Future Emissions 2664.4 Projections of Atmospheric Composition for the 21st Century 2674.5 Open Questions 2774.6 Overall Impact of Global Atmospheric Chemistry Change 279

  1. Theoretical Insight into Shocked Gases

    Energy Technology Data Exchange (ETDEWEB)

    Leiding, Jeffery Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-29

    I present the results of statistical mechanical calculations on shocked molecular gases. This work provides insight into the general behavior of shock Hugoniots of gas phase molecular targets with varying initial pressures. The dissociation behavior of the molecules is emphasized. Impedance matching calculations are performed to determine the maximum degree of dissociation accessible for a given flyer velocity as a function of initial gas pressure.

  2. Positron diffusion in noble gases

    International Nuclear Information System (INIS)

    Stromswold, D.C.; Lee, Y.K.

    1975-01-01

    Positron diffusion in helium, neon, and argon has been observed and the lifetimes of free positrons in these gases have been calculated on the basis of assumed theoretical behavior. The results are summarized for various gas pressures at room temperature. Reported lifetimes are comparable to the extrapolated values of 1.4 μsec in He and 0.2 μsec in Ar obtained at one atmosphere by Falk. (7 figures, 2 tables) (U.S.)

  3. Annihilation in Gases and Galaxies

    Science.gov (United States)

    Drachman, Richard J. (Editor)

    1990-01-01

    This publication contains most of the papers, both invited and contributed, that were presented at the Workshop of Annihilation in Gases and Galaxies. This was the fifth in a biennial series associated with the International Conference on the Physics of Electronic and Atomic Collisions. Subjects covered included the scattering and annihilation of positrons and positronium atoms in various media, including those of astrophysical interest. In addition, the topics of antimatter and dark matter were covered.

  4. Diagnosis of basal cell carcinoma by two photon excited fluorescence combined with lifetime imaging

    Science.gov (United States)

    Fan, Shunping; Peng, Xiao; Liu, Lixin; Liu, Shaoxiong; Lu, Yuan; Qu, Junle

    2014-02-01

    Basal cell carcinoma (BCC) is the most common type of human skin cancer. The traditional diagnostic procedure of BCC is histological examination with haematoxylin and eosin staining of the tissue biopsy. In order to reduce complexity of the diagnosis procedure, a number of noninvasive optical methods have been applied in skin examination, for example, multiphoton tomography (MPT) and fluorescence lifetime imaging microscopy (FLIM). In this study, we explored two-photon optical tomography of human skin specimens using two-photon excited autofluorescence imaging and FLIM. There are a number of naturally endogenous fluorophores in skin sample, such as keratin, melanin, collagen, elastin, flavin and porphyrin. Confocal microscopy was used to obtain structures of the sample. Properties of epidermic and cancer cells were characterized by fluorescence emission spectra, as well as fluorescence lifetime imaging. Our results show that two-photon autofluorescence lifetime imaging can provide accurate optical biopsies with subcellular resolution and is potentially a quantitative optical diagnostic method in skin cancer diagnosis.

  5. Hypoxia positron emission tomography imaging: combining information on perfusion and tracer retention to improve hypoxia specificity

    DEFF Research Database (Denmark)

    Busk, Morten; Munk, Ole L; Jakobsen, Steen S

    2017-01-01

    BACKGROUND: Static positron emission tomography (PET) allows mapping of tumor hypoxia, but low resolution and slow tracer retention/clearance results in poor image contrast and the risk of missing areas where hypoxic cells and necrosis are intermixed. Fully dynamic PET may improve accuracy but scan...

  6. Tracking Iron in Multiple Sclerosis: A Combined Imaging and Histopathological Study at 7 Tesla

    Science.gov (United States)

    Bagnato, Francesca; Hametner, Simon; Yao, Bing; van Gelderen, Peter; Merkle, Hellmut; Cantor, Fredric K.; Lassmann, Hans; Duyn, Jeff H.

    2011-01-01

    Previous authors have shown that the transverse relaxivity R[subscript 2][superscript *] and frequency shifts that characterize gradient echo signal decay in magnetic resonance imaging are closely associated with the distribution of iron and myelin in the brain's white matter. In multiple sclerosis, iron accumulation in brain tissue may reflect a…

  7. Combined Diffusion Tensor Imaging and Transverse Relaxometry in Early-Onset Bipolar Disorder

    Science.gov (United States)

    Gonenc, Atilla; Frazier, Jean A.; Crowley, David J.; Moore, Constance M.

    2010-01-01

    Objective: Transverse relaxation time (T2) imaging provides the opportunity to examine membrane fluidity, which can affect a number of cellular functions. The objective of the present work was to examine T2 abnormalities in children with unmodified DSM-IV-TR bipolar disorder (BD) in bilateral cingulate-paracingulate (CPC) white matter. Method: A…

  8. Visual and quantitative evaluation of selected image combination schemes in ultrasound spatial compound scanning

    DEFF Research Database (Denmark)

    Wilhjelm, Jens E.; Jensen, M.S.; Jespersen, S.K.

    2004-01-01

    , mean-excluding-maximum (mem), root-mean-square (rms), geometric mean and maximum) on image quality (tissue delineation and artifacts), speckle signal-to-noise ratio (SNRs) and contrast. The evaluation is based on in vitro SAI (+/-21degrees in steps of Deltatheta = 7degrees) of formalin fixed porcine...

  9. Automatic Segmentation of Granular Objects in Images: Combining Local Density Clustering and Gradient-Barrier Watershed

    Science.gov (United States)

    2014-01-01

    Cytometry Part A 56A (2003) 23–36. [10] F. Long, H. Peng, E. Myers , Automatic segmentation of nuclei in 3D microscopy images of C. elegans. In...Chen, H. Tagare, S. Thiruvenkadam, F. Huang, D. Wilson, K. Gopinath, R. Briggs , E. Geiser, Using prior shapes in geometric active contours in a

  10. A rare combination of findings revealed by MR imaging in the Marfan syndrome

    International Nuclear Information System (INIS)

    Kleimaker, G.; Ehrenheim C.; Rittierodt, M.; Jaster, S.; Hundeshagen, H.

    1996-01-01

    We report on the case of a 16-year-old boy known to have suffered form the Marfan syndrome for the past ten years. Even though he could not be regarded as a text-book perfect example, he showed some rare manifestations of the disease. Particular attention is given to the diagnostic possibilities offered by MR imaging. (orig./MG) [de

  11. Combined 3-dimensional and mirror-image analysis for the diagnosis of asymmetry

    NARCIS (Netherlands)

    Damstra, Janalt; Oosterkamp, Barbara Constance Maria; Jansma, Johan; Ren, Yijin

    2011-01-01

    Three-dimensional imaging techniques have greatly improved our ability to assess asymmetry by means of linear and angular measurements. However, visualizing deformities enables a unique appreciation of the underlying deformity, which might not be possible by looking at quantitative numbers alone.

  12. Combined analysis of cervical smears. Cytopathology, image cytometry and in situ hybridization

    DEFF Research Database (Denmark)

    Multhaupt, H; Bruder, E; Elit, L

    1993-01-01

    This study was an attempt to correlate the Bethesda System of Papanicolaou smear classification with DNA content by image analysis and the presence of human papillomavirus (HPV) as determined by in situ hybridization. DNA histograms were classified as normal diploid, diploid proliferative, polypl...

  13. Experimental evaluation of electrical conductivity imaging of anisotropic brain tissues using a combination of diffusion tensor imaging and magnetic resonance electrical impedance tomography

    Energy Technology Data Exchange (ETDEWEB)

    Sajib, Saurav Z. K.; Jeong, Woo Chul; Oh, Tong In; Kim, Hyung Joong, E-mail: bmekim@khu.ac.kr, E-mail: ejwoo@khu.ac.kr; Woo, Eung Je, E-mail: bmekim@khu.ac.kr, E-mail: ejwoo@khu.ac.kr [Department of Biomedical Engineering, Kyung Hee University, Seoul 02447 (Korea, Republic of); Kyung, Eun Jung [Department of Pharmacology, Chung-Ang University, Seoul 06974 (Korea, Republic of); Kim, Hyun Bum [Department of East-West Medical Science, Kyung Hee University, Yongin 17104 (Korea, Republic of); Kwon, Oh In [Department of Mathematics, Konkuk University, Seoul 05029 (Korea, Republic of)

    2016-06-15

    Anisotropy of biological tissues is a low-frequency phenomenon that is associated with the function and structure of cell membranes. Imaging of anisotropic conductivity has potential for the analysis of interactions between electromagnetic fields and biological systems, such as the prediction of current pathways in electrical stimulation therapy. To improve application to the clinical environment, precise approaches are required to understand the exact responses inside the human body subjected to the stimulated currents. In this study, we experimentally evaluate the anisotropic conductivity tensor distribution of canine brain tissues, using a recently developed diffusion tensor-magnetic resonance electrical impedance tomography method. At low frequency, electrical conductivity of the biological tissues can be expressed as a product of the mobility and concentration of ions in the extracellular space. From diffusion tensor images of the brain, we can obtain directional information on diffusive movements of water molecules, which correspond to the mobility of ions. The position dependent scale factor, which provides information on ion concentration, was successfully calculated from the magnetic flux density, to obtain the equivalent conductivity tensor. By combining the information from both techniques, we can finally reconstruct the anisotropic conductivity tensor images of brain tissues. The reconstructed conductivity images better demonstrate the enhanced signal intensity in strongly anisotropic brain regions, compared with those resulting from previous methods using a global scale factor.

  14. Experimental evaluation of electrical conductivity imaging of anisotropic brain tissues using a combination of diffusion tensor imaging and magnetic resonance electrical impedance tomography

    Science.gov (United States)

    Sajib, Saurav Z. K.; Jeong, Woo Chul; Kyung, Eun Jung; Kim, Hyun Bum; Oh, Tong In; Kim, Hyung Joong; Kwon, Oh In; Woo, Eung Je

    2016-06-01

    Anisotropy of biological tissues is a low-frequency phenomenon that is associated with the function and structure of cell membranes. Imaging of anisotropic conductivity has potential for the analysis of interactions between electromagnetic fields and biological systems, such as the prediction of current pathways in electrical stimulation therapy. To improve application to the clinical environment, precise approaches are required to understand the exact responses inside the human body subjected to the stimulated currents. In this study, we experimentally evaluate the anisotropic conductivity tensor distribution of canine brain tissues, using a recently developed diffusion tensor-magnetic resonance electrical impedance tomography method. At low frequency, electrical conductivity of the biological tissues can be expressed as a product of the mobility and concentration of ions in the extracellular space. From diffusion tensor images of the brain, we can obtain directional information on diffusive movements of water molecules, which correspond to the mobility of ions. The position dependent scale factor, which provides information on ion concentration, was successfully calculated from the magnetic flux density, to obtain the equivalent conductivity tensor. By combining the information from both techniques, we can finally reconstruct the anisotropic conductivity tensor images of brain tissues. The reconstructed conductivity images better demonstrate the enhanced signal intensity in strongly anisotropic brain regions, compared with those resulting from previous methods using a global scale factor.

  15. Combined nonlinear laser imaging (two-photon excitation fluorescence, second and third-harmonic generation, and fluorescence lifetime imaging microscopies) in ovarian tumors

    Science.gov (United States)

    Adur, J.; Pelegati, V. B.; de Thomaz, A. A.; Bottcher-Luiz, F.; Andrade, L. A. L. A.; Almeida, D. B.; Carvalho, H. F.; Cesar, C. L.

    2012-03-01

    We applied Two-photon Excited Fluorescence (TPEF), Second/Third Harmonic Generation (SHG and THG) and Fluorescence Lifetime Imaging (FLIM) Non Linear Optics (NLO) Laser-Scanning Microscopy within the same imaging platform to evaluate their use as a diagnostic tool in ovarian tumors. We assess of applicability of this multimodal approach to perform a pathological evaluation of serous and mucinous tumors in human samples. The combination of TPEF-SHG-THG imaging provided complementary information about the interface epithelium/stromal, such as the transformation of epithelium surface (THG) and the overall fibrillar tissue architecture (SHG). The fact that H&E staining is the standard method used in clinical pathology and that the stored samples are usually fixed makes it important a re-evaluation of these samples with NLO microscopy to compare new results with a library of already existing samples. FLIM, however, depends on the chemical environment around the fluorophors that was completely changed after fixation; therefore it only makes sense in unstained samples. Our FLIM results in unstained samples demonstrate that it is possible to discriminate healthy epithelia from serous or mucinous epithelia. Qualitative and quantitative analysis of the different imaging modalities used showed that multimodal nonlinear microscopy has the potential to differentiate between cancerous and healthy ovarian tissue.

  16. Prostate cancer: a comparative study of {sup 11}C-choline PET and MR imaging combined with proton MR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, Takako; Lee, Jin; Takahashi, Nobukazu; Oka, Takashi; Shizukuishi, Kazuya; Inoue, Tomio [Yokohama City University School of Medicine, Department of Radiology, Yokohama (Japan); Uemura, Hiroji; Kubota, Yoshinobu [Yokohama City University School of Medicine, Department of Urology, Kanagawa (Japan); Sasaki, Takeshi [Yokohama City University School of Medicine, Department of Pathology, Kanagawa (Japan); Endou, Hisashi [Yokohama City University School of Medicine, Department of Pharmacy, Kanagawa (Japan)

    2005-07-01

    Prostate cancer is difficult to visualise in its early stages using current imaging technology. The present study aimed to clarify the utility of {sup 11}C-choline PET for localising and evaluating cancer lesions in patients with prostate cancer by conducting a prospective comparison with magnetic resonance (MR) imaging combined with proton MR spectroscopy. PET and MR imaging combined with proton MR spectroscopy were performed in 20 patients with prostate cancer. Correlations among the metabolite ratio of choline + creatine to citrate (Cho+Cr/Ci) on MR spectroscopy, serum PSA and maximum standardised uptake value (SUV{sub max}) of {sup 11}C-choline were assessed. The location of the primary lesion was assessed by the site of SUV{sub max} and the laterality of the highest Cho+Cr/Ci ratio and confirmed by examination of surgical pathology specimens (n=16). PET exhibited a diagnostic sensitivity of 100% (20/20) for primary lesions, while the sensitivities of MR imaging and MR spectroscopy were 60% (12/20) and 65% (13/20), respectively. Weak linear correlations were observed between SUV{sub max} and serum PSA (r=0.52, p<0.05), and between SUV{sub max} and Cho+Cr/Ci ratio (r=0.49, p<0.05). Regarding the localisation of main primary lesions, PET results agreed with pathological findings in 13 patients (81%) ({kappa}=0.59), while MR spectroscopy results were in accordance with pathological findings in eight patients (50%) ({kappa}=0.11). This preliminary study suggests that {sup 11}C-choline PET may provide more accurate information regarding the localisation of main primary prostate cancer lesions than MR imaging/MR spectroscopy. A further clinical study of {sup 11}C-choline PET in a large number of patients suspected of prostate cancer will be necessary to determine the clinical utility of {sup 11}C-choline PET in patients who clinically require biopsy. (orig.)

  17. Magnetic Resonance Imaging of Intracranial Hypotension: Diagnostic Value of Combined Qualitative Signs and Quantitative Metrics.

    Science.gov (United States)

    Aslan, Kerim; Gunbey, Hediye Pinar; Tomak, Leman; Ozmen, Zafer; Incesu, Lutfi

    The aim of this study was to investigate whether the use of combination quantitative metrics (mamillopontine distance [MPD], pontomesencephalic angle, and mesencephalon anterior-posterior/medial-lateral diameter ratios) with qualitative signs (dural enhancement, subdural collections/hematoma, venous engorgement, pituitary gland enlargements, and tonsillar herniations) provides a more accurate diagnosis of intracranial hypotension (IH). The quantitative metrics and qualitative signs of 34 patients and 34 control subjects were assessed by 2 independent observers. Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic performance of quantitative metrics and qualitative signs, and for the diagnosis of IH, optimum cutoff values of quantitative metrics were found with ROC analysis. Combined ROC curve was measured for the quantitative metrics, and qualitative signs combinations in determining diagnostic accuracy and sensitivity, specificity, and positive and negative predictive values were found, and the best model combination was formed. Whereas MPD and pontomesencephalic angle were significantly lower in patients with IH when compared with the control group (P qualitative signs, the highest individual distinctive power was dural enhancement with area under the ROC curve (AUC) of 0.838. For quantitative metrics, the highest individual distinctive power was MPD with AUC of 0.947. The best accuracy in the diagnosis of IH was obtained by combination of dural enhancement, venous engorgement, and MPD with an AUC of 1.00. This study showed that the combined use of dural enhancement, venous engorgement, and MPD had diagnostic accuracy of 100 % for the diagnosis of IH. Therefore, a more accurate IH diagnosis can be provided with combination of quantitative metrics with qualitative signs.

  18. Landfill gases and some effects on vegetation

    Science.gov (United States)

    Franklin B. Flower; Ida A. Leone; Edward F. Gilman; John J. Arthur

    1977-01-01

    Gases moving from refuse landfills through soil were studied in New Jersey. The gases, products of anaerobic decomposition of organic matter in the refuse, caused injury and death of peach trees, ornamentals, and commercial farm crops, and create possible hazards to life and property because of the entrance of combustible gases into residences. Remedial measures are...

  19. 40 CFR 1065.750 - Analytical gases.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Analytical gases. 1065.750 Section 1065.750 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS..., span, and calibration gases. For example, it may be necessary to store bottles of condensable gases in...

  20. A Combined Use of Decomposition and Texture for Terrain Classification of Fully Polarimetric SAR Images

    Science.gov (United States)

    Rodionova, N. V.

    2007-03-01

    This p aper presents two-stag e unsupervised terrain classification of fully polarimetr ic SA R data using Freeman and Durden decomposition based on three simp le scattering mechanisms: surface, volume and double bounce (first step), and textur al features (uncorrelated uniformity , contr ast, inv erse mo men t and entropy) obtained from grey lev el co-occurrence matr ices (GLCM) (second step). Textural f eatures ar e defined in moving w indow 5x5 pixels w ith N=32 (N - number of grey lev els) . This algorith m preserves th e purity of domin ant polarimetric scattering properties and defines textural features in each scatter ing category. It is shown better object discrimin ation after app lying textur e w ith in fix ed scattering category. Speckle r eduction is one of th e main mo ments in imag e interpr etation improvement because of its great influen ce on textur e. Results from unfiltered and Lee filtered polar imetr ic SAR imag es show that the v alues of contrast and en tropy decr ease and th e values of uniformity and inverse moment increase with speckle reduction, that's tru e for all polarizations (HH, VV, HV). Th e d iscr imination b etw een objects increases after speckle f ilter ing. Polar ization influen ce on textur e features is def ined by calculating th e features in SAR images w ith HH , VV and HV polarizations before and after speck le filter ing, and then creating RG B images. It is shown mor e polarization inf luence on textur e features (uniformity , inverse mo ment and entropy) before filtering and less influen ce - after speck le f iltering. I t's not true for contrast wher e polar ization influen ce is not ch anged practically w ith filtering. SIR-C/X-SA R SLC L-band imag es of Moscow r egion are used for illustr ation.

  1. Combining nanotechnology with current biomedical knowledge for the vascular imaging and treatment of atherosclerosis.

    Science.gov (United States)

    Slevin, M; Badimon, L; Grau-Olivares, M; Ramis, M; Sendra, J; Morrison, M; Krupinski, J

    2010-03-01

    Activation of vasa vasorum (the microvessels supplying the major arteries) at specific sites in the adventitia initiates their proliferation or 'angiogenesis' concomitant with development of atherosclerotic plaques. Haemorrhagic, leaky blood vessels from unstable plaques proliferate abnormally, are of relatively large calibre but are immature neovessels poorly invested with smooth muscle cells and possess structural weaknesses which may contribute to instability of the plaque by facilitation of inflammatory cell infiltration and haemorrhagic complications. Weak neovascular beds in plaque intima as well as activated adventitial blood vessels are potential targets for molecular imaging and targeted drug therapy, however, the majority of tested, currently available imaging and therapeutic agents have been unsuccessful because of their limited capacity to reach and remain stably within the target tissue or cells in vivo. Nanoparticle technology together with magnetic resonance imaging has allowed the possibility of imaging of neovessels in coronary or carotid plaques, and infusion of nanoparticle suspensions using infusion catheters or implant-based drug delivery represents a novel and potentially much more efficient option for treatment. This review will describe the importance of angiogenesis in mediation of plaque growth and development of plaque instability and go on to investigate the possibility of future design of superparamagnetic/perfluorocarbon-derived nanoparticles for imaging of the vasculature in this disease or which could be directed to the adventitial vasa vasorum or indeed intimal microvessels and which can release active payloads directed against primary key external mitogens and intracellular signalling molecules in endothelial cells responsible for their activation with a view to inhibition of angiogenesis.

  2. Turnover and transport of greenhouse gases in a Danish wetland

    DEFF Research Database (Denmark)

    Jørgensen, Christian Juncher

    2011-01-01

    Natural wetlands act as both sources and sinks of greenhouse gases such as carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) from the soil to the atmosphere. Production and consumption of these gases in the soil are controlled by a series of highly dynamic and interrelated processes...... net N2O dynamics. Similarly, plant-mediated gas transport by the subsurface aerating macrophyte Phalaris arundinacea played a major part in regulating and facilitating emissions of greenhouse gases across the soil-atmosphere interface. It is concluded that the spatiotemporal distribution of dominating...... N2O producing and consuming processes below the surface, in combination with the variations in the diffusive exchange rates due to soil water content and apparent diffusivity, control the magnitude and timing of N2O emissions to the atmosphere in close connection with the plant-mediated gas...

  3. Innovative techniques for image-guided ablation of benign thyroid nodules: Combined ethanol and radiofrequency ablation

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hye Sun; Baek, Jung Hwan; Choi, Young Jun; Lee, Jeong Hyun [Dept. of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of)

    2017-06-15

    In the treatment of benign thyroid nodules, ethanol ablation (EA), and radiofrequency ablation (RFA) have been suggested for cystic and solid thyroid nodules, respectively. Although combining these ablation techniques may be effective, no guidelines for or reviews of the combination have been published. Currently, there are three ways of combining EA and RFA: additional RFA is effective for treatment of incompletely resolved symptoms and solid residual portions of a thyroid nodule after EA. Additional EA can be performed for the residual unablated solid portion of a nodule after RFA if it is adjacent to critical structures (e.g., trachea, esophagus, and recurrent laryngeal nerve). In the concomitant procedure, ethanol is injected to control venous oozing after aspiration of cystic fluid prior to RFA of the remaining solid nodule.

  4. Combined Tensor Fitting and TV Regularization in Diffusion Tensor Imaging Based on a Riemannian Manifold Approach.

    Science.gov (United States)

    Baust, Maximilian; Weinmann, Andreas; Wieczorek, Matthias; Lasser, Tobias; Storath, Martin; Navab, Nassir

    2016-08-01

    In this paper, we consider combined TV denoising and diffusion tensor fitting in DTI using the affine-invariant Riemannian metric on the space of diffusion tensors. Instead of first fitting the diffusion tensors, and then denoising them, we define a suitable TV type energy functional which incorporates the measured DWIs (using an inverse problem setup) and which measures the nearness of neighboring tensors in the manifold. To approach this functional, we propose generalized forward- backward splitting algorithms which combine an explicit and several implicit steps performed on a decomposition of the functional. We validate the performance of the derived algorithms on synthetic and real DTI data. In particular, we work on real 3D data. To our knowledge, the present paper describes the first approach to TV regularization in a combined manifold and inverse problem setup.

  5. Combined arterial and venous whole-body MR angiography with cardiac MR imaging in patients with thromboembolic disease - initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Vogt, Florian M.; Hunold, Peter; Barkhausen, Joerg [University Hospital Essen, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Herborn, Christoph U. [University Hospital Hamburg-Eppendorf, Medical Prevention Center Hamburg (MPCH) at University Hospital Hamburg-Eppendorf, Hamburg (Germany); Ruehm, Stefan G. [David Geffen School of Medicine at UCLA, Department of Radiology, Los Angeles, CA (United States); Kroger, Knut [University Hospital Essen, Department of Angiology, Essen (Germany)

    2008-05-15

    The objective was to assess the feasibility of a combined arterial and venous whole-body three-dimensional magnetic resonance (MR) angiography, together with a cardiac MR examination, in patients with arterial thromboembolism. Ten patients with arterial thromboembolism underwent a contrast-enhanced whole-body MR examination of the arterial and venous vessels, followed by a cardiac MR examination on a separate occasion within 24 h. All examinations were performed on a 1.5-T MR scanner. For both arterial and venous MR angiography only one injection of contrast agent was necessary. The cardiac imaging protocol included dark-blood-prepared half-Fourier acquisition single-shot turbo-spin-echo sequences, fast steady-state free precession cine sequences, T2-weighted turbo-spin-echo sequences and inversion recovery gradient-echo fast low-angle-shot sequences after injection of contrast agent. MR imaging revealed additional clinically unknown arterial thromboembolisms in four patients. The thoracic aorta was depicted as embolic source in four patients, while deep vein thrombosis (DVT) was found in one patient as the underlying disease. Unsuspected infarction of parenchymal organs was detected by MRI in two patients. An unknown additional DVT was found in one patient. Four patients were considered to have arterial emboli of cardiac origin. In conclusion, acquisition of arterial and venous MR angiograms of the entire vascular system combined with cardiac MR imaging is a most comprehensive and valuable strategy in patients with arterial thromboembolism. (orig.)

  6. Magnified endoscopy combined with narrow band imaging of minimal superficial esophageal neoplasia-indicators to differentiate intraepithelial neoplasias.

    Science.gov (United States)

    Mochizuki, Yosuke; Saito, Yasuharu; Kobori, Ayako; Ban, Hiromitsu; Shioya, Makoto; Nishimura, Takashi; Inatomi, Osamu; Bamba, Shigeki; Tsujikawa, Tomoyuki; Ishida, Mitsuaki; Andoh, Akira; Fujiyama, Yoshihide

    2012-12-01

    Clinical application of narrow band imaging facilitates diagnosis of esophageal neoplasia. However, no previous investigation has been conducted on magnifying endoscopy combined with narrow band imaging in detection of minimal superficial esophageal neoplasia, which is defined as neoplasia neoplasia. Between January 2005 and November 2011, 53 minimal superficial esophageal neoplasias in 40 patients were diagnosed by screening upper gastrointestinal endoscopy with narrow band imaging at our hospital. We investigated findings including brownish dots, brownish epithelium, and demarcation line of minimal superficial esophageal neoplasia diagnosed histopathologically as low-grade intraepithelial neoplasia, high-grade intraepithelial neoplasia, and squamous cell carcinoma. Significantly more brownish dots (P neoplasia compared with low-grade neoplasia. When minimal superficial esophageal neoplasia was diagnosed as high-grade intraepithelial neoplasia or squamous cell carcinoma, sensitivity, specificity, positive predictive value, and negative predictive value were 88.9, 42.9, 44.4, and 88.2%, respectively, for brownish dots; 94.4, 51.4, 50.0, and 94.7%, respectively, for brownish epithelium; and 66.7, 62.9, 48.0, and 78.6%, respectively, for demarcation line. The combined technique was useful in the differential diagnosis of minimal superficial esophageal neoplasia.

  7. Combined fluorescence and phase contrast imaging at the Advanced Photon Source.

    Energy Technology Data Exchange (ETDEWEB)

    Hornberger, B.; Feser, M.; Jacobsen, C.; Vogt, S.; Legnini, D.; Paterson, D.; Rehak, P.; DeGeronimo, G.; Palmer, B.M.; Experimental Facilities Division (APS); State Univ. of New York at Stony Brook Univ.; BNL; Univ. of Vermont

    2006-01-01

    X-ray fluorescence microprobes excel at detecting and quantifying trace metals in biological and environmental science samples, but typically do not detect low Z elements such as carbon and nitrogen. Therefore, it is hard to put the trace metals into context with their natural environment. We are implementing phase contrast capabilities with a segmented detector into several microprobes at the Advanced Photon Source (APS) to address this problem. Qualitative differential phase contrast images from a modified soft x-ray detector already provide very useful information for general users. We are also implementing a quantitative method to recover the absolute phase shift by Fourier filtering detector images. New detectors are under development which are optimized for the signal levels present at the APS. In this paper, we concentrate on fundamental signal to noise considerations comparing absorption and differential phase contrast.

  8. Combining convolutional neural networks and Hough Transform for classification of images containing lines

    Science.gov (United States)

    Sheshkus, Alexander; Limonova, Elena; Nikolaev, Dmitry; Krivtsov, Valeriy

    2017-03-01

    In this paper, we propose an expansion of convolutional neural network (CNN) input features based on Hough Transform. We perform morphological contrasting of source image followed by Hough Transform, and then use it as input for some convolutional filters. Thus, CNNs computational complexity and the number of units are not affected. Morphological contrasting and Hough Transform are the only additional computational expenses of introduced CNN input features expansion. Proposed approach was demonstrated on the example of CNN with very simple structure. We considered two image recognition problems, that were object classification on CIFAR-10 and printed character recognition on private dataset with symbols taken from Russian passports. Our approach allowed to reach noticeable accuracy improvement without taking much computational effort, which can be extremely important in industrial recognition systems or difficult problems utilising CNNs, like pressure ridge analysis and classification.

  9. Combined optoacoustic and high-frequency ultrasound imaging of live mouse embryos

    Science.gov (United States)

    Chitnis, Parag V.; Aristizbal, Orlando; Filoux, Erwan; Sampathkumar, Ashwinkumar; Mamou, Jonathan; Turnbull, Daniel H.; Ketterling, Jeffrey A.

    2012-02-01

    The cell differentiation and proliferation of the central nervous system (CNS) are closely related to vascular development. An imaging protocol that integrated optoacoustics (OA) with high-frequency ultrasound (HFU) was developed for in vivo imaging of brain ventricles and vasculature in mouse embryos. A 40-MHz, co-polymer, 5-element annular-array transducer with a geometric focus of 12 mm was modified to accommodate free-beam, coaxial illumination. Three-dimensional (3-D) data sets were acquired by raster scanning the transducer-optics assembly in 50-μm increments. A single intact conceptus from an anesthetized mouse was surgically exposed into PBS-filled Petri-dish. An 800-μm spot illumination from a pulsed, 532-nm, Nd-YAG laser was synchronized with a high-voltage impulse excitation of the central array element to facilitate simultaneous and spatially coregistered OA and HFU data acquisition. The resulting OA and HFU signals from each scan location were recorded on all five array channels and post-processed using a synthetic-focusing algorithm to enhance the depth of field (DOF). Dual-modality images were acquired from mouse embryos at E11.5, E12.5, and E13.5 days of gestation. The extended DOF allowed morphologically accurate visualization of the embryonic head. The brain ventricles were segmented from the HFU data and rendered in 3-D. The OA data provided visualization of the vascular plexus as well as individual blood vessels. Feasibility of spatially co-registered, low-cost dual-modality in vivo imaging of mouse embryos was demonstrated.

  10. Combined analysis of surface reflection imaging and vertical seismic profiling at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Daley, T.M.; Majer, E.L.; Karageorgi, E.

    1994-08-01

    This report presents results from surface and borehole seismic profiling performed by the Lawrence Berkeley Laboratory (LBL) on Yucca Mountain. This work was performed as part of the site characterization effort for the potential high-level nuclear waste repository. Their objective was to provide seismic imaging from the near surface (200 to 300 ft. depth) to the repository horizon and below, if possible. Among the issues addressed by this seismic imaging work are location and depth of fracturing and faulting, geologic identification of reflecting horizons, and spatial continuity of reflecting horizons. The authors believe their results are generally positive, with tome specific successes. This was the first attempt at this scale using modem seismic imaging techniques to determine geologic features on Yucca Mountain. The principle purpose of this report is to present the interpretation of the seismic reflection section in a geologic context. Three surface reflection profiles were acquired and processed as part of this study. Because of environmental concerns, all three lines were on preexisting roads. Line 1 crossed the mapped surface trace of the Ghost Dance fault and it was intended to study the dip and depth extent of the fault system. Line 2 was acquired along Drill Hole wash and was intended to help the ESF north ramp design activities. Line 3 was acquired along Yucca Crest and was designed to image geologic horizons which were thought to be less faulted along the ridge. Unfortunately, line 3 proved to have poor data quality, in part because of winds, poor field conditions and limited time. Their processing and interpretation efforts were focused on lines 1 and 2 and their associated VSP studies

  11. Geometric Context and Orientation Map Combination for Indoor Corridor Modeling Using a Single Image

    Science.gov (United States)

    Baligh Jahromi, Ali; Sohn, Gunho

    2016-06-01

    Since people spend most of their time indoors, their indoor activities and related issues in health, security and energy consumption have to be understood. Hence, gathering and representing spatial information of indoor spaces in form of 3D models become very important. Considering the available data gathering techniques with respect to the sensors cost and data processing time, single images proved to be one of the reliable sources. Many of the current single image based indoor space modeling methods are defining the scene as a single box primitive. This domain-specific knowledge is usually not applicable in various cases where multiple corridors are joined at one scene. Here, we addressed this issue by hypothesizing-verifying multiple box primitives which represents the indoor corridor layout. Middle-level perceptual organization is the foundation of the proposed method, which relies on finding corridor layout boundaries using both detected line segments and virtual rays created by orthogonal vanishing points. Due to the presence of objects, shadows and occlusions, a comprehensive interpretation of the edge relations is often concealed. This necessitates the utilization of virtual rays to create a physically valid layout hypothesis. Many of the former methods used Orientation Map or Geometric Context to evaluate their proposed layout hypotheses. Orientation map is a map that reveals the local belief of region orientations computed from line segments, and in a segmented image geometric context uses color, texture, edge, and vanishing point cues to estimate the likelihood of each possible label for all super-pixels. Here, the created layout hypotheses are evaluated by an objective function which considers the fusion of orientation map and geometric context with respect to the horizontal viewing angle at each image pixel. Finally, the best indoor corridor layout hypothesis which gets the highest score from the scoring function will be selected and converted to a 3D

  12. Three-dimensional esophagus reconstruction and monitoring during ablation of atrial fibrillation: combination of two imaging techniques.

    Science.gov (United States)

    Scazzuso, Fernando A; Rivera, Santiago H; Albina, Gastón; de la Paz Ricapito, María; Gómez, Luis Alberto; Sanmartino, Victoria; Kamlofsky, Matías; Laiño, Ruben; Giniger, Alberto

    2013-10-03

    The purpose of the study was to determine the accuracy of a novel three-dimensional (3D) imaging integration technique of the esophagus combining multislice computed tomography (CT) scan of the esophagus into the three-dimensional (3D) electroanatomic map just before pulmonary vein (PV) isolation. We included 94 consecutive patients with symptomatic atrial fibrillation (AF) who underwent ablation. All patients had a CT performed prior procedure that was integrated to the 3D reconstruction electromechanical map of the atrium and the esophagus (Verismo(TM), EnSite® NavX version 7.0 J, St. Jude Medical Inc.). During the procedure, a quadripolar electrophysiology catheter placed in the esophagus was used for mapping and to monitor esophagus position. Integrated (fusion) images were used to determinate the esophagus position compared to the left atrium posterior wall and its relationship with PV ostiums. We compared esophagus position by CT and fusion images. Procedural success was 97.9% with no fatal complications. Esophagus locations were as follows: left 57%, right 7%, oblique course 11% and central 25%. Agreements in esophageal position between CT and fusion imaging techniques were 83.3% and 64% for patients with a recent (≤48 h) and non-recent CT assessment (>48 h), respectively. Throughout the procedure, esophagus stability was 88.8% (lateral displacement<15 mm). Ablative strategy was modified in 51% of the cases due to awareness of esophagus location. Guidance of AF ablation with 3D fusion images was safe and effective. CT images of the esophagus, especially if acquired within 48 h before ablation, ensure appropriate intraprocedural localization of the esophagus. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  13. Predicting post-hepatectomy liver failure by combined volumetric, functional MR image and laboratory analysis.

    Science.gov (United States)

    Chuang, Yi-Hsuan; Ou, Hsin-You; Lazo, Marirose Z; Chen, Chao-Long; Chen, Meng-Hsiang; Weng, Ching-Chun; Cheng, Yu-Fan

    2017-10-07

    To assess the efficacy of functional MR image with volumetric, liver function test and indocyanine green clearance (ICG) in identifying the patients who are at risk of post-hepatectomy liver failure (PHLF). We retrospectively included 115 patients undergoing gadoxetic acid-enhanced MR imaging before hepatectomy at one medical centre from January 2013 to December 2015. Contrast enhancement ratio (CER) between transitional and hepatobiliary phases (3 and 30 minutes post-contrast) was calculated. Total liver volume (TLV) and spleen volume (Sp) were measured. Post-operatively, the histological Ishak fibrosis score was collected. Potential risk factors for liver failure were analysed, and the performance was examined by receiver operating characteristic curve. Post-hepatectomy liver failure (PHLF) occurred in 16 patients (13.9%). TLV/SLV, ADC value, CER HBP/TP and total liver contrast enhancement ratio (tCER) were associated with PHLF (P imaging with volumetric is a reliable method for evaluating functional liver volume and determining the risk of PHLF. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Live cell imaging combined with high-energy single-ion microbeam

    International Nuclear Information System (INIS)

    Guo, Na; Du, Guanghua; Liu, Wenjing; Wu, Ruqun; Wei, Junzhe; Guo, Jinlong; Chen, Hao

    2016-01-01

    DNA strand breaks can lead to cell carcinogenesis or cell death if not repaired rapidly and efficiently. An online live cell imaging system was established at the high energy microbeam facility at the Institute of Modern Physics to study early and fast cellular response to DNA damage after high linear energy transfer ion radiation. The HT1080 cells expressing XRCC1-RFP were irradiated with single high energy nickel ions, and time-lapse images of the irradiated cells were obtained online. The live cell imaging analysis shows that strand-break repair protein XRCC1 was recruited to the ion hit position within 20 s in the cells and formed bright foci in the cell nucleus. The fast recruitment of XRCC1 at the ion hits reached a maximum at about 200 s post-irradiation and then was followed by a slower release into the nucleoplasm. The measured dual-exponential kinetics of XRCC1 protein are consistent with the proposed consecutive reaction model, and the measurements obtained that the reaction rate constant of the XRCC1 recruitment to DNA strand break is 1.2 × 10 −3 s −1 and the reaction rate constant of the XRCC1 release from the break-XRCC1 complex is 1.2 × 10 −2 s −1 .

  15. Live cell imaging combined with high-energy single-ion microbeam

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Na; Du, Guanghua, E-mail: gh-du@impcas.ac.cn; Liu, Wenjing; Wu, Ruqun; Wei, Junzhe [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou (China); Guo, Jinlong [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou (China); Northwest Normal University, Lanzhou (China); Chen, Hao [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou (China); Institute of Nuclear Science and Technology, University of Lanzhou, Lanzhou (China)

    2016-03-15

    DNA strand breaks can lead to cell carcinogenesis or cell death if not repaired rapidly and efficiently. An online live cell imaging system was established at the high energy microbeam facility at the Institute of Modern Physics to study early and fast cellular response to DNA damage after high linear energy transfer ion radiation. The HT1080 cells expressing XRCC1-RFP were irradiated with single high energy nickel ions, and time-lapse images of the irradiated cells were obtained online. The live cell imaging analysis shows that strand-break repair protein XRCC1 was recruited to the ion hit position within 20 s in the cells and formed bright foci in the cell nucleus. The fast recruitment of XRCC1 at the ion hits reached a maximum at about 200 s post-irradiation and then was followed by a slower release into the nucleoplasm. The measured dual-exponential kinetics of XRCC1 protein are consistent with the proposed consecutive reaction model, and the measurements obtained that the reaction rate constant of the XRCC1 recruitment to DNA strand break is 1.2 × 10{sup −3} s{sup −1} and the reaction rate constant of the XRCC1 release from the break-XRCC1 complex is 1.2 × 10{sup −2} s{sup −1}.

  16. Live cell imaging combined with high-energy single-ion microbeam

    Science.gov (United States)

    Guo, Na; Du, Guanghua; Liu, Wenjing; Guo, Jinlong; Wu, Ruqun; Chen, Hao; Wei, Junzhe

    2016-03-01

    DNA strand breaks can lead to cell carcinogenesis or cell death if not repaired rapidly and efficiently. An online live cell imaging system was established at the high energy microbeam facility at the Institute of Modern Physics to study early and fast cellular response to DNA damage after high linear energy transfer ion radiation. The HT1080 cells expressing XRCC1-RFP were irradiated with single high energy nickel ions, and time-lapse images of the irradiated cells were obtained online. The live cell imaging analysis shows that strand-break repair protein XRCC1 was recruited to the ion hit position within 20 s in the cells and formed bright foci in the cell nucleus. The fast recruitment of XRCC1 at the ion hits reached a maximum at about 200 s post-irradiation and then was followed by a slower release into the nucleoplasm. The measured dual-exponential kinetics of XRCC1 protein are consistent with the proposed consecutive reaction model, and the measurements obtained that the reaction rate constant of the XRCC1 recruitment to DNA strand break is 1.2 × 10-3 s-1 and the reaction rate constant of the XRCC1 release from the break-XRCC1 complex is 1.2 × 10-2 s-1.

  17. Canonical partition functions: ideal quantum gases, interacting classical gases, and interacting quantum gases

    OpenAIRE

    Zhou, Chi-Chun; Dai, Wu-Sheng

    2017-01-01

    In statistical mechanics, for a system with fixed number of particles, e.g., a finite-size system, strictly speaking, the thermodynamic quantity needs to be calculated in the canonical ensemble. Nevertheless, the calculation of the canonical partition function is difficult; even the canonical partition function of ideal Bose and Fermi gases cannot be obtained exactly. In this paper, based on the mathematical theory of the symmetric function and the Bell polynomial, we suggest a method for the...

  18. Combination of contrast-enhanced wall motion analysis and myocardial deformation imaging during dobutamine stress echocardiography.

    Science.gov (United States)

    Nagy, Anikó I; Sahlén, Anders; Manouras, Aristomenis; Henareh, Loghman; da Silva, Cristina; Günyeli, Elif; Apor, Astrid A; Merkely, Béla; Winter, Reidar

    2015-01-01

    The combination of deformation analysis with conventional wall motion scoring (WMS) has been shown to increase the diagnostic sensitivity of dobutamine stress echocardiography (DSE). The feasibility and diagnostic power of WMS is largely improved by contrast agents; however, they are not used in combination with deformation analysis, as contrast agents are generally considered to render strain measurement unfeasible. To assess the feasibility of tissue velocity (TVI)- and 2D speckle tracking (ST)-based strain analysis during contrast-enhanced DSE; and to show whether there is an incremental value in combining deformation analysis with contrast-enhanced WMS. DS echocardiograms containing native, tissue Doppler, and contrast-enhanced loops of 60 patients were analysed retrospectively. The feasibility of WMS, TVI-, and ST-strain measurement was determined in 40 patients according to pre-defined criteria. The diagnostic ability of a combined protocol integrating data from contrast-WMS and TVI-strain measurement was then compared with contrast-WMS alone in all 60 patients, using coronary angiograms as a gold standard. Both TVI- and ST-based strain analysis were feasible during contrast-DSE (feasibility at peak stress: 87 and 75%). At the patient level, the diagnostic accuracy of the combined method did not prove superior to contrast-WMS (82 vs. 78%); a trend towards improved sensitivity and specificity for detecting coronary artery disease in the right coronary artery circulation (sensitivity: 85 vs. 77%, P = NS; specificity: 96 vs. 94%) was, however, observed. Both TVI- and ST-based myocardial deformation analysis are feasible during contrast-enhanced DSE, however, our results fail to demonstrate a clear diagnostic benefit of additional strain analysis over expert WMS alone. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

  19. Tomographic bioluminescence imaging by use of a combined optical-PET (OPET) system: a computer simulation feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Alexandrakis, George [David Geffen School of Medicine at UCLA, Crump Institute for Molecular Imaging, University of California, 700 Westwood Plaza, Los Angeles, CA 90095 (United States); Rannou, Fernando R [Departamento de Ingenieria Informatica, Universidad de Santiago de Chile (USACH), Av. Ecuador 3659, Santiago (Chile); Chatziioannou, Arion F [David Geffen School of Medicine at UCLA, Crump Institute for Molecular Imaging, University of California, 700 Westwood Plaza, Los Angeles, CA 90095 (United States)

    2005-09-07

    The feasibility and limits in performing tomographic bioluminescence imaging with a combined optical-PET (OPET) system were explored by simulating its image formation process. A micro-MRI based virtual mouse phantom was assigned appropriate tissue optical properties to each of its segmented internal organs at wavelengths spanning the emission spectrum of the firefly luciferase at 37 deg. C. The TOAST finite-element code was employed to simulate the diffuse transport of photons emitted from bioluminescence sources in the mouse. OPET measurements were simulated for single-point, two-point and distributed bioluminescence sources located in different organs such as the liver, the kidneys and the gut. An expectation maximization code was employed to recover the intensity and location of these simulated sources. It was found that spectrally resolved measurements were necessary in order to perform tomographic bioluminescence imaging. The true location of emission sources could be recovered if the mouse background optical properties were known a priori. The assumption of a homogeneous optical property background proved inadequate for describing photon transport in optically heterogeneous tissues and led to inaccurate source localization in the reconstructed images. The simulation results pointed out specific methodological challenges that need to be addressed before a practical implementation of OPET-based bioluminescence tomography is achieved.

  20. Anterolateral subluxation of the tibia associated with combined anterior cruciate and medial collateral ligament tears: MR imaging of the knee

    International Nuclear Information System (INIS)

    Park, Jin Gyoon; Kang, Heoung Keun; Lee, Joong K.; Phelps, Carlton T.

    1995-01-01

    To evaluate the passive subluxation of the tibia on MR imaging in patient with both anterior cruciate ligament (ACL) and medial collateral ligament (MCL) tears and to demonstrate the usefulness of its measurement. The authors performed a retrospective study of 123 knees with tears of both ACL (complete, n = 70, partial, n = 53) and MCL (complete, n = 10, partial, n 113). ACL tears were documented at arthroscopy and MCL tears were interpreted by abnormal MR findings. One hundred normal knees were also studied for comparison. Using new internal landmarks, anterior subluxation was measured on an intercondylar sagittal image and lateral subluxation was measured on a mid-coronal image. Anterior subluxation of 3 mm or more was seen in 45/123(37%) abnormal knees, lateral subluxation of 3 mm or more in 20/123(16%), and anterolateral subluxation in 15/123(12%). Anterior subluxation of 5 mm or more was seen in 25/70(36%) complete ACL tears, and no knees with partial ACL tears showed anterior subluxation of 5 mm or more. Static anterolateral subluxation of the tibia occurs in knees with combined ACL and MCL tears, as measured on routine MR imaging. These measurements may help confirm the presence of ligament injuries and differentiate complete from partial ACL tear

  1. Anterolateral subluxation of the tibia associated with combined anterior cruciate and medial collateral ligament tears: MR imaging of the knee

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jin Gyoon; Kang, Heoung Keun [Chonnam University Medical School, Kwangju (Korea, Republic of); Lee, Joong K.; Phelps, Carlton T. [Albany Medical College and Albany Medical Center Hospital, Newyork (United States)

    1995-09-15

    To evaluate the passive subluxation of the tibia on MR imaging in patient with both anterior cruciate ligament (ACL) and medial collateral ligament (MCL) tears and to demonstrate the usefulness of its measurement. The authors performed a retrospective study of 123 knees with tears of both ACL (complete, n = 70, partial, n = 53) and MCL (complete, n = 10, partial, n 113). ACL tears were documented at arthroscopy and MCL tears were interpreted by abnormal MR findings. One hundred normal knees were also studied for comparison. Using new internal landmarks, anterior subluxation was measured on an intercondylar sagittal image and lateral subluxation was measured on a mid-coronal image. Anterior subluxation of 3 mm or more was seen in 45/123(37%) abnormal knees, lateral subluxation of 3 mm or more in 20/123(16%), and anterolateral subluxation in 15/123(12%). Anterior subluxation of 5 mm or more was seen in 25/70(36%) complete ACL tears, and no knees with partial ACL tears showed anterior subluxation of 5 mm or more. Static anterolateral subluxation of the tibia occurs in knees with combined ACL and MCL tears, as measured on routine MR imaging. These measurements may help confirm the presence of ligament injuries and differentiate complete from partial ACL tear.

  2. LOW COMPLEXITY HYBRID LOSSY TO LOSSLESS IMAGE CODER WITH COMBINED ORTHOGONAL POLYNOMIALS TRANSFORM AND INTEGER WAVELET TRANSFORM

    Directory of Open Access Journals (Sweden)

    R. Krishnamoorthy

    2012-05-01

    Full Text Available In this paper, a new lossy to lossless image coding scheme combined with Orthogonal Polynomials Transform and Integer Wavelet Transform is proposed. The Lifting Scheme based Integer Wavelet Transform (LS-IWT is first applied on the image in order to reduce the blocking artifact and memory demand. The Embedded Zero tree Wavelet (EZW subband coding algorithm is used in this proposed work for progressive image coding which achieves efficient bit rate reduction. The computational complexity of lower subband coding of EZW algorithm is reduced in this proposed work with a new integer based Orthogonal Polynomials transform coding. The normalization and mapping are done on the subband of the image for exploiting the subjective redundancy and the zero tree structure is obtained for EZW coding and so the computation complexity is greatly reduced in this proposed work. The experimental results of the proposed technique also show that the efficient bit rate reduction is achieved for both lossy and lossless compression when compared with existing techniques.

  3. Multifunctional superparamagnetic nanoshells: combining two-photon luminescence imaging, surface-enhanced Raman scattering and magnetic separation

    Science.gov (United States)

    Jin, Xiulong; Li, Haiyan; Wang, Shanshan; Kong, Ni; Xu, Hong; Fu, Qihua; Gu, Hongchen; Ye, Jian

    2014-11-01

    With the increasing need for multi-purpose analysis in the biomedical field, traditional single diagnosis methods cannot meet the requirements. Therefore new multifunctional technologies and materials for the integration of sample collection, sensing and imaging are in great demand. Core-shell nanoparticles offer a unique platform to combine multifunctions in a single particle. In this work, we have constructed a novel type of core-shell superparamagnetic nanoshell (Fe3O4@SiO2@Au), composed of a Fe3O4 cluster core, a thin Au shell and a SiO2 layer in between. The obtained multifunctional nanoparticles combine the magnetic properties and plasmonic optical properties effectively, which were well investigated by a number of experimental characterization methods and theoretical simulations. We have demonstrated that Fe3O4@SiO2@Au nanoparticles can be utilized for two-photon luminescence (TPL) imaging, near-infrared surface-enhanced Raman scattering (NIR SERS) and cell collection by magnetic separation. The TPL intensity could be further greatly enhanced through the plasmon coupling effect in the self-assembled nanoparticle chains, which were triggered by an external magnetic field. In addition, Fe3O4@SiO2@Au nanoparticles may have great potential applications such as enhanced magnetic resonance imaging (MRI) and photo-thermotherapy. Successful combination of multifunctions including magnetic response, biosensing and bioimaging in single nanoparticles allows further manipulation, real-time tracking, and intracellular molecule analysis of live cells at a single-cell level.With the increasing need for multi-purpose analysis in the biomedical field, traditional single diagnosis methods cannot meet the requirements. Therefore new multifunctional technologies and materials for the integration of sample collection, sensing and imaging are in great demand. Core-shell nanoparticles offer a unique platform to combine multifunctions in a single particle. In this work, we have

  4. On the Combination of Differential Emission Measure Analysis and Rotational Tomography for Three-dimensional Solar EUV Imaging

    Science.gov (United States)

    Frazin, R. A.; Kamalabadi, F.; Weber, M. A.

    2005-08-01

    Conventional differential emission measure (DEM) analysis allows one to determine the amount of plasma as a function of temperature along a given line of sight. A completely different technique called solar rotational tomography (SRT) exploits the view angles provided by solar rotation to determine the spatial distribution of emissivity in three dimensions. These two techniques can be combined in a procedure called differential emission measure tomography (DEMT) to determine the DEM at each point in the corona with the same spatial resolution as can normally be achieved by SRT. In this paper the theory of DEMT is presented, and numerical examples based on the Atmospheric Imaging Assembly (AIA) are given. The results demonstrate promising potential for the methods to be adapted for use with other EUV and X-ray imaging and/or spectroscopy instruments.

  5. Gd³⁺ Tethered Gold Nanorods for Combined Magnetic Resonance Imaging and Photo-Thermal Therapy.

    Science.gov (United States)

    Pitchaimani, Arunkumar; Duong, Tuyen; Nguyen, Thanh; Maurmann, Leila; Key, Jaehong; Bossmann, Stefan H; Aryal, Santosh

    2017-04-01

    Near infrared (NIR) mediated photothermal therapy and magnetic resonance imaging (MRI) are promising treatment and imaging modalities in the field of cancer theranostics. Gold nanorods are the first choice of materials for NIR-mediated photothermal therapy due to their strong localized surface plasmon resonance (LSPR) at NIR region. Similarly, gadolinium based MRI contrast agents have an ability to increase the ionic and molecular relaxivity, thereby enhancing the solvent proton relaxation rate resulting in contrast enhancement. Herein, the effort has been made to engineer a dual front theranostic agent with combined photothermal and magnetic resonance imaging capacity using gadolinium tethered gold nanorods (Gd3+-AuNR). NIR-responsive gold nanorods were surface fabricated by means of Au-thiol interaction using a thiolated macrocyclic chelator that chelates Gd3+ ions, and further stabilized by thiolated polyethylene glycol (PEG-SH). The magnetic properties of the Gd3+-AuNR displayed an enhanced r 1 relaxivity of 12.1 mM–1s–1, with higher biological stability, and contrast enhancement in both solution state and in cell pellets. In-vitro (cell-free) and ex-vivo (on pig skin) analysis of the Gd3+-AuNR shows enhanced photothermal properties as equivalent to that of the raw AuNR. Furthermore, Gd3+-AuNR showed competent cellular entry and intracellular distribution as revealed by hyperspectral microscopy. In addition, Gd3+-AuNR also exhibits significant thermal ablation of B16–F10 cells in the presence of NIR. Thus, Gd3+-AuNR features a significant theranostic potential with combined photothermal and imaging modality, suggesting a great potential in anticancer therapy.

  6. A novel technique combining laparoscopic and endovascular approaches using image fusion guidance for anterior embolization of type II endoleak

    Directory of Open Access Journals (Sweden)

    M. Mujeeb Zubair, MD

    2017-03-01

    Full Text Available Type II endoleak (T2E leading to aneurysm sac enlargement is one of the challenging complications associated with endovascular aneurysm repair. Recent guidelines recommend embolization of T2E associated with aneurysmal sac enlargement. Various percutaneous and endovascular techniques have been reported for embolization of T2E. We report a novel technique for T2E embolization combining laparoscopic and endovascular approaches using preoperative image fusion. We believe our technique provides a more direct access to the lumbar feeding vessels that is typically challenging with transarterial or translumbar embolization techniques.

  7. Combined use of spin-echo and gradient-echo MR-imaging in cervical disk disease

    Energy Technology Data Exchange (ETDEWEB)

    Neuhold, A.; Stiskal, M.; Platzer, C. (Krankenanstalt Rudolfinerhaus, Vienna (Austria). Dept. of Diagnostic Imaging); Pernecky, G. (Krankenanstalt Rudolfinerhaus, Vienna (Austria). Neurosurgical Dept.); Brainin, M. (Landesnervenklinik Klosterneuburg-Gugging (Austria). Neurological Dept.)

    1991-10-01

    In a prospective study we compared the diagnostic value of combined gradient-echo (GE) and spin-echo (SE) MR imaging with cervical myelography in 30 patients with clinical signs and symptoms of cervical radiculopathy and/or myelopathy due to disk disease. Only patients who subsequently underwent surgery (anterior interbody approach) were included. By means of MRI the clinically relevant segment was identified in all cases, by means of myelography in all but two patients. Using both spin-echo (SE) and gradient-echo (GE) techniques it was possible to differentiate between bone tissue and disk material by MR in all but one. (orig./GDG).

  8. Combined use of spin-echo and gradient-echo MR-imaging in cervical disk disease

    International Nuclear Information System (INIS)

    Neuhold, A.; Stiskal, M.; Platzer, C.; Pernecky, G.; Brainin, M.

    1991-01-01

    In a prospective study we compared the diagnostic value of combined gradient-echo (GE) and spin-echo (SE) MR imaging with cervical myelography in 30 patients with clinical signs and symptoms of cervical radiculopathy and/or myelopathy due to disk disease. Only patients who subsequently underwent surgery (anterior interbody approach) were included. By means of MRI the clinically relevant segment was identified in all cases, by means of myelography in all but two patients. Using both spin-echo (SE) and gradient-echo (GE) techniques it was possible to differentiate between bone tissue and disk material by MR in all but one. (orig./GDG)

  9. The use of high-field intra-operative magnetic resonance imaging combined with language functional neuronavigation in glioma surgery

    OpenAIRE

    Yan ZHAO; Xiao-lei CHEN; Fei WANG; Guo-chen SUN; Yu-bo WANG; Zhi-jun SONG; Bai-nan XU

    2011-01-01

    Objective To explore the effect of high-field intra-operative magnetic resonance imaging(iMRI) combined with language functional neuronavigation in resection of glioma in language area of dominant hemisphere of the brain.Methods Twenty right handed patients(12 males and 8 females,aged from 20 to 61 years with mean of 43.6 years) with glioma close to arcuate fasciculus were involved in present study,and they were stratified into normal group(n=9) and aphasia group(n=11) according to the preope...

  10. A novel technique combining laparoscopic and endovascular approaches using image fusion guidance for anterior embolization of type II endoleak.

    Science.gov (United States)

    Zubair, M Mujeeb; Chinnadurai, Ponraj; Loh, Francis E; Loh, Thomas M; Lumsden, Alan B; Bechara, Carlos F

    2017-03-01

    Type II endoleak (T2E) leading to aneurysm sac enlargement is one of the challenging complications associated with endovascular aneurysm repair. Recent guidelines recommend embolization of T2E associated with aneurysmal sac enlargement. Various percutaneous and endovascular techniques have been reported for embolization of T2E. We report a novel technique for T2E embolization combining laparoscopic and endovascular approaches using preoperative image fusion. We believe our technique provides a more direct access to the lumbar feeding vessels that is typically challenging with transarterial or translumbar embolization techniques.

  11. Genetically encoded calcium indicators for multi-color neural activity imaging and combination with optogenetics

    Directory of Open Access Journals (Sweden)

    Jasper eAkerboom

    2013-03-01

    Full Text Available Genetically encoded calcium indicators (GECIs are powerful tools for systems neuroscience. Here we describe red, single-wavelength GECIs, RCaMPs, engineered from circular permutation of the thermostable red fluorescent protein mRuby. High-resolution crystal structures of mRuby, the red sensor RCaMP, and the recently published red GECI R-GECO1 give insight into the chromophore environments of the Ca2+-bound state of the sensors and the engineered protein domain interfaces of the different indicators. We characterized the biophysical properties and performance of RCaMP sensors in vitro and in vivo in Caenorhabditis elegans, Drosophila larvae, and larval zebrafish. Further, we demonstrate 2-color calcium imaging both within the same cell (registering mitochondrial and somatic [Ca2+] and between two populations of cells: neurons and astrocytes. Finally, we perform integrated optogenetics experiments, wherein neural activation via channelrhodopsin-2 (ChR2 or a red-shifted variant, and activity imaging via RCaMP or GCaMP, are conducted simultaneously, with the ChR2/RCaMP pair providing independently addressable spectral channels. Using this paradigm, we measure calcium responses of naturalistic and ChR2-evoked muscle contractions in vivo in crawling C. elegans. We systematically compare the RCaMP sensors to R-GECO1, in terms of action potential-evoked fluorescence increases in neurons, photobleaching, and photoswitching. R-GECO1 displays higher Ca2+ affinity and larger dynamic range than RCaMP, but exhibits significant photoactivation with blue and green light, suggesting that integrated channelrhodopsin-based optogenetics using R-GECO1 may be subject to artifact. Finally, we create and test blue, cyan and yellow variants engineered from GCaMP by rational design. This engineered set of chromatic variants facilitates new experiments in functional imaging and optogenetics.

  12. Laboratory observations of sediment transport using combined particle image and tracking velocimetry (Conference Presentation)

    Science.gov (United States)

    Frank, Donya; Calantoni, Joseph

    2017-05-01

    Improved understanding of coastal hydrodynamics and morphology will lead to more effective mitigation measures that reduce fatalities and property damage caused by natural disasters such as hurricanes. We investigated sediment transport under oscillatory flow over flat and rippled beds with phase-separated stereoscopic Particle Image Velocimetry (PIV). Standard PIV techniques severely limit measurements at the fluid-sediment interface and do not allow for the observation of separate phases in multi-phase flow (e.g. sand grains in water). We have implemented phase-separated Particle Image Velocimetry by adding fluorescent tracer particles to the fluid in order to observe fluid flow and sediment transport simultaneously. While sand grains scatter 532 nm wavelength laser light, the fluorescent particles absorb 532 nm laser light and re-emit light at a wavelength of 584 nm. Optical long-pass filters with a cut-on wavelength of 550 nm were installed on two cameras configured to perform stereoscopic PIV to capture only the light emitted by the fluorescent tracer particles. A third high-speed camera was used to capture the light scattered by the sand grains allowing for sediment particle tracking via particle tracking velocimetry (PTV). Together, these overlapping, simultaneously recorded images provided sediment particle and fluid velocities at high temporal and spatial resolution (100 Hz sampling with 0.8 mm vector spacing for the 2D-3C fluid velocity field). Measurements were made under a wide range of oscillatory flows over flat and rippled sand beds. The set of observations allow for the investigation of the relative importance of pressure gradients and shear stresses on sediment transport.

  13. Optical image encryption based on phase retrieval combined with three-dimensional particle-like distribution

    International Nuclear Information System (INIS)

    Chen, Wen; Chen, Xudong; Sheppard, Colin J R

    2012-01-01

    We propose a new phase retrieval algorithm for optical image encryption in three-dimensional (3D) space. The two-dimensional (2D) plaintext is considered as a series of particles distributed in 3D space, and an iterative phase retrieval algorithm is developed to encrypt the series of particles into phase-only masks. The feasibility and effectiveness of the proposed method are demonstrated by a numerical experiment, and the advantages and security of the proposed optical cryptosystems are also analyzed and discussed. (paper)

  14. Combined image guided monitoring the pharmacokinetics of rapamycin loaded human serum albumin nanoparticles with a split luciferase reporter

    Science.gov (United States)

    Wang, Fu; Yang, Kai; Wang, Zhe; Ma, Ying; Gutkind, J. Silvio; Hida, Naoki; Niu, Gang; Tian, Jie

    2016-02-01

    Imaging guided techniques have been increasingly employed to investigate the pharmacokinetics (PK) and biodistribution of nanoparticle based drug delivery systems. In most cases, however, the PK profiles of drugs could vary significantly from those of drug delivery carriers upon administration in the blood circulation, which complicates the interpretation of image findings. Herein we applied a genetically encoded luciferase reporter in conjunction with near infrared (NIR) fluorophores to investigate the respective PK profiles of a drug and its carrier in a biodegradable drug delivery system. In this system, a prototype hydrophobic agent, rapamycin (Rapa), was encapsulated into human serum albumin (HSA) to form HSA Rapa nanoparticles, which were then labeled with Cy5 fluorophore to facilitate the fluorescence imaging of HSA carrier. Meanwhile, we employed transgenetic HN12 cells that were modified with a split luciferase reporter, whose bioluminescence function is regulated by Rapa, to reflect the PK profile of the encapsulated agent. It was interesting to discover that there existed an obvious inconsistency of PK behaviors between HSA carrier and rapamycin in vitro and in vivo through near infrared fluorescence imaging (NIFRI) and bioluminescence imaging (BLI) after treatment with Cy5 labeled HSA Rapa. Nevertheless, HSA Rapa nanoparticles manifested favorable in vivo PK and tumor suppression efficacy in a follow-up therapeutic study. The developed strategy of combining a molecular reporter and a fluorophore in this study could be extended to other drug delivery systems to provide profound insights for non-invasive real-time evaluation of PK profiles of drug-loaded nanoparticles in pre-clinical studies.Imaging guided techniques have been increasingly employed to investigate the pharmacokinetics (PK) and biodistribution of nanoparticle based drug delivery systems. In most cases, however, the PK profiles of drugs could vary significantly from those of drug delivery

  15. Toward Fourier interferometry fluorescence excitation/emission imaging of malignant cells combined with photoacoustic microscopy

    Science.gov (United States)

    Kohen, Elli; Hirschberg, Joseph G.; Berry, John P.; Ozkutuk, Nuri; Ornek, Ceren; Monti, Marco; Leblanc, Roger M.; Schachtschabel, Dietrich O.; Haroon, Sumaira

    2003-10-01

    Dual excitation fluorescence imaging has been used as a first step towards multi-wavelength excitation/emission fluorescence spectral imaging. Target cells are transformed keratinocytes, and other osteosarcoma, human breast and color cancer cells. Mitochondrial membrane potential probes, e.g. TMRM (tetramethylrhodamine methyl ester), Mitotracker Green (Molecular Probes, Inc., Eugene OR,USA; a recently synthesized mitochondrial oxygen probe, [PRE,P1"- pyrene butyl)-2-rhodamine ester] allow dual excitation in the UV plus in teh blue-green spectral regions. Also, using the natural endogenous probe NAD(P)H, preliminary results indicate mitochondrial responses to metabolic challenges (e.g. glucose addition), plus changes in mitochonrial distribution and morphology. In terms of application to biomedicine (for diagnostiscs, prognostsics and drug trials) three parameters have been selected in addition to the natural probe NAD(P)H, i.e. vital fluorescence probing of mitochondria, lysosomes and Golgi apparatus. It is hoped that such a multiparameter approach will allow malignant cell characterization and grading. A new area being introduced is the use of similar methodology for biotechnical applications such as the study of the hydrogen-producing alga Chlamydomonas Reinhardtii, and possible agricultural applications, such as Saccharomyces yeast for oenology. Complementation by Photoacoustic Microscopy is also contemplated, to study the internal conversion component which follows the excitation by photons.

  16. Generalized Chirp Scaling Combined with Baseband Azimuth Scaling Algorithm for Large Bandwidth Sliding Spotlight SAR Imaging.

    Science.gov (United States)

    Yi, Tianzhu; He, Zhihua; He, Feng; Dong, Zhen; Wu, Mnaqing

    2017-05-29

    This paper presents an efficient and precise imaging algorithm for the large bandwidth sliding spotlight synthetic aperture radar (SAR). The existing sub-aperture processing method based on the baseband azimuth scaling (BAS) algorithm cannot cope with the high order phase coupling along the range and azimuth dimensions. This coupling problem causes defocusing along the range and azimuth dimensions. This paper proposes a generalized chirp scaling (GCS)-BAS processing algorithm, which is based on the GCS algorithm. It successfully mitigates the deep focus along the range dimension of a sub-aperture of the large bandwidth sliding spotlight SAR, as well as high order phase coupling along the range and azimuth dimensions. Additionally, the azimuth focusing can be achieved by this azimuth scaling method. Simulation results demonstrate the ability of the GCS-BAS algorithm to process the large bandwidth sliding spotlight SAR data. It is proven that great improvements of the focus depth and imaging accuracy are obtained via the GCS-BAS algorithm.

  17. Use of MODIS Sensor Images Combined with Reanalysis Products to Retrieve Net Radiation in Amazonia.

    Science.gov (United States)

    de Oliveira, Gabriel; Brunsell, Nathaniel A; Moraes, Elisabete C; Bertani, Gabriel; Dos Santos, Thiago V; Shimabukuro, Yosio E; Aragão, Luiz E O C

    2016-06-24

    In the Amazon region, the estimation of radiation fluxes through remote sensing techniques is hindered by the lack of ground measurements required as input in the models, as well as the difficulty to obtain cloud-free images. Here, we assess an approach to estimate net radiation (Rn) and its components under all-sky conditions for the Amazon region through the Surface Energy Balance Algorithm for Land (SEBAL) model utilizing only remote sensing and reanalysis data. The study period comprised six years, between January 2001-December 2006, and images from MODIS sensor aboard the Terra satellite and GLDAS reanalysis products were utilized. The estimates were evaluated with flux tower measurements within the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) project. Comparison between estimates obtained by the proposed method and observations from LBA towers showed errors between 12.5% and 16.4% and 11.3% and 15.9% for instantaneous and daily Rn, respectively. Our approach was adequate to minimize the problem related to strong cloudiness over the region and allowed to map consistently the spatial distribution of net radiation components in Amazonia. We conclude that the integration of reanalysis products and satellite data, eliminating the need for surface measurements as input model, was a useful proposition for the spatialization of the radiation fluxes in the Amazon region, which may serve as input information needed by algorithms that aim to determine evapotranspiration, the most important component of the Amazon hydrological balance.

  18. Multispectral scanning laser ophthalmoscopy combined with optical coherence tomography for simultaneous in vivo mouse retinal imaging

    Science.gov (United States)

    Zhang, Pengfei; Zam, Azhar; Jian, Yifan; Wang, Xinlei; Burns, Marie E.; Sarunic, Marinko V.; Pugh, Edward N.; Zawadzki, Robert J.

    2015-03-01

    A compact, non-invasive multi-modal system has been developed for in vivo mouse retina imaging. It is configured for simultaneously detecting green and red fluorescent protein signals with scanning laser ophthalmoscopy (SLO) back-scattered light from the SLO illumination beam, and depth information about different retinal layers by means of Optical Coherence Tomography (OCT). Simultaneous assessment of retinal characteristics with different modalities can provide a wealth of information about the structural and functional changes in the retinal neural tissue and chorio-retinal vasculature in vivo. Additionally, simultaneous acquisition of multiple channels facilitates analysis of the data of different modalities by automatic temporal and structural co-registration. As an example of the instrument's performance we imaged the retina of a mouse with constitutive expression of GFP in microglia cells (Cx3cr1GFP/+), and which also expressed the red fluorescent protein mCherry in Müller glial cells by means of adeno-associated virus delivery (AAV2) of an mCherry cDNA driven by the GFAP (glial fibrillary acid protein) promoter.

  19. Diatom Valve Three-Dimensional Representation: A New Imaging Method Based on Combined Microscopies

    Directory of Open Access Journals (Sweden)

    Maria Antonietta Ferrara

    2016-09-01

    Full Text Available The frustule of diatoms, unicellular microalgae, shows very interesting photonic features, generally related to its complicated and quasi-periodic micro- and nano-structure. In order to simulate light propagation inside and through this natural structure, it is important to develop three-dimensional (3D models for synthetic replica with high spatial resolution. In this paper, we present a new method that generates images of microscopic diatoms with high definition, by merging scanning electron microscopy and digital holography microscopy or atomic force microscopy data. Starting from two digital images, both acquired separately with standard characterization procedures, a high spatial resolution (Δz = λ/20, Δx = Δy ≅ 100 nm, at least 3D model of the object has been generated. Then, the two sets of data have been processed by matrix formalism, using an original mathematical algorithm implemented on a commercially available software. The developed methodology could be also of broad interest in the design and fabrication of micro-opto-electro-mechanical systems.

  20. Diatom Valve Three-Dimensional Representation: A New Imaging Method Based on Combined Microscopies.

    Science.gov (United States)

    Ferrara, Maria Antonietta; De Tommasi, Edoardo; Coppola, Giuseppe; De Stefano, Luca; Rea, Ilaria; Dardano, Principia

    2016-09-28

    The frustule of diatoms, unicellular microalgae, shows very interesting photonic features, generally related to its complicated and quasi-periodic micro- and nano-structure. In order to simulate light propagation inside and through this natural structure, it is important to develop three-dimensional (3D) models for synthetic replica with high spatial resolution. In this paper, we present a new method that generates images of microscopic diatoms with high definition, by merging scanning electron microscopy and digital holography microscopy or atomic force microscopy data. Starting from two digital images, both acquired separately with standard characterization procedures, a high spatial resolution (Δ z = λ/20, Δ x = Δ y ≅ 100 nm, at least) 3D model of the object has been generated. Then, the two sets of data have been processed by matrix formalism, using an original mathematical algorithm implemented on a commercially available software. The developed methodology could be also of broad interest in the design and fabrication of micro-opto-electro-mechanical systems.

  1. Method for purification of gases

    Energy Technology Data Exchange (ETDEWEB)

    Hastrup, N.E.

    1981-11-17

    The present invention is directed to a method for selective purification of gases. The method comprises feeding an exhaust gas containing a solid impurity and a gaseous impurity to a separator. A substantial portion of the solid impurity is separated. Then, the partially-purified gas is fed to a spray dryer. That gas is sprayed with an absorption agent to separate gaseous impurities. Then, the further, partially-purified gas is fed to another separator to separate remaining solid impurity. An exhaust gas which is substantially free of solid and gaseous impurities and fly ash having a desired quality are recovered.

  2. Mechanics of liquids and gases

    CERN Document Server

    Loitsyanskii, L G; Jones, W P

    1966-01-01

    Mechanics of Liquids and Gases, Second Edition is a 10-chapter text that covers significant revisions concerning the dynamics of an ideal gas, a viscous liquid and a viscous gas.After an expanded introduction to the fundamental properties and methods of the mechanics of fluids, this edition goes on dealing with the kinetics and general questions of dynamics. The next chapters describe the one-dimensional pipe flow of a gas with friction, the elementary theory of the shock tube; Riemann's theory of the wave propagation of finite intensity, and the theory of plane subsonic and supersonic flows.

  3. Ultrasonic waves in classical gases

    Science.gov (United States)

    Magner, A. G.; Gorenstein, M. I.; Grygoriev, U. V.

    2017-12-01

    The velocity and absorption coefficient for the plane sound waves in a classical gas are obtained by solving the Boltzmann kinetic equation, which describes the reaction of the single-particle distribution function to a periodic external field. Within the linear response theory, the nonperturbative dispersion equation valid for all sound frequencies is derived and solved numerically. The results are in agreement with the approximate analytical solutions found for both the frequent- and rare-collision regimes. These results are also in qualitative agreement with the experimental data for ultrasonic waves in dilute gases.

  4. Climate Change and Greenhouse Gases

    Science.gov (United States)

    Ledley, Tamara S.; Sundquist, Eric; Schwartz, Stephen; Hall, Dorothy K.; Fellows, Jack; Killeen, Timothy

    1999-01-01

    The American Geophysical Union (AGU), as a scientific organization devoted to research on the Earth and space sciences, provides current scientific information to the public on issues pertinent to geophysics. The Council of the AGU approved a position statement on Climate Change and Greenhouse Gases in December 1998. The statement, together with a short summary of the procedures that were followed in its preparation, review, and adoption were published in the February 2, 1999 issue of Eos ([AGU, 1999]. The present article reviews scientific understanding of this issue as presented in peer-reviewed publications that serves as the underlying basis of the position statement.

  5. Combining anatomical, diffusion, and resting state functional magnetic resonance imaging for individual classification of mild and moderate Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Tijn M. Schouten

    2016-01-01

    Full Text Available Magnetic resonance imaging (MRI is sensitive to structural and functional changes in the brain caused by Alzheimer's disease (AD, and can therefore be used to help in diagnosing the disease. Improving classification of AD patients based on MRI scans might help to identify AD earlier in the disease's progress, which may be key in developing treatments for AD. In this study we used an elastic net classifier based on several measures derived from the MRI scans of mild to moderate AD patients (N=77 from the prospective registry on dementia study and controls (N=173 from the Austrian Stroke Prevention Family Study. We based our classification on measures from anatomical MRI, diffusion weighted MRI and resting state functional MRI. Our unimodal classification performance ranged from an area under the curve (AUC of 0.760 (full correlations between functional networks to 0.909 (grey matter density. When combining measures from multiple modalities in a stepwise manner, the classification performance improved to an AUC of 0.952. This optimal combination consisted of grey matter density, white matter density, fractional anisotropy, mean diffusivity, and sparse partial correlations between functional networks. Classification performance for mild AD as well as moderate AD also improved when using this multimodal combination. We conclude that different MRI modalities provide complementary information for classifying AD. Moreover, combining multiple modalities can substantially improve classification performance over unimodal classification.

  6. Combining Spectral Data and a DSM from UAS-Images for Improved Classification of Non-Submerged Aquatic Vegetation

    Directory of Open Access Journals (Sweden)

    Eva Husson

    2017-03-01

    Full Text Available Monitoring of aquatic vegetation is an important component in the assessment of freshwater ecosystems. Remote sensing with unmanned aircraft systems (UASs can provide sub-decimetre-resolution aerial images and is a useful tool for detailed vegetation mapping. In a previous study, non-submerged aquatic vegetation was successfully mapped using automated classification of spectral and textural features from a true-colour UAS-orthoimage with 5-cm pixels. In the present study, height data from a digital surface model (DSM created from overlapping UAS-images has been incorporated together with the spectral and textural features from the UAS-orthoimage to test if classification accuracy can be improved further. We studied two levels of thematic detail: (a Growth forms including the classes of water, nymphaeid, and helophyte; and (b dominant taxa including seven vegetation classes. We hypothesized that the incorporation of height data together with spectral and textural features would increase classification accuracy as compared to using spectral and textural features alone, at both levels of thematic detail. We tested our hypothesis at five test sites (100 m × 100 m each with varying vegetation complexity and image quality using automated object-based image analysis in combination with Random Forest classification. Overall accuracy at each of the five test sites ranged from 78% to 87% at the growth-form level and from 66% to 85% at the dominant-taxon level. In comparison to using spectral and textural features alone, the inclusion of height data increased the overall accuracy significantly by 4%–21% for growth-forms and 3%–30% for dominant taxa. The biggest improvement gained by adding height data was observed at the test site with the most complex vegetation. Height data derived from UAS-images has a large potential to efficiently increase the accuracy of automated classification of non-submerged aquatic vegetation, indicating good possibilities

  7. Clinical value of 99Tcm-MIBI imaging combined with serum tumor markers in diagnosis of benign and malignant pulmonary nodules

    International Nuclear Information System (INIS)

    Zhao Yigang; Song Bo

    2016-01-01

    Objective: To evaluate the significance of 99 Tc m -MIBI imaging combined with serum tumor markers (NSE, CYFRA21-1) in diagnosis of pulmonary nodules. Methods: 54 patients who were detected pulmonary nodules by Computed Tomography(CT) were involved in this study. All of them underwent 99 Tc m -MIBI imaging and serum tumor markers testing. The sensitivity, specificity and accuracy of two methods were calculated respectively and the sensitivity, specificity, accuracy, positive predictive value, negative predictive value of combined application of two methods were also calculated. Results: The accuracy rate and positive predictive value of 99 Tc m -MIBI imaging combined with serum tumor markers were higher than that of alone detection(P < 0.05). The specificity of the combination detection was higher than that of tumor marker detection(P < 0.05). There was no significantly difference on the specificity between combination detection and 99 Tc m -MIBI imaging(P > 0.05). The sensitivity, negative predictive value among combination, 99 Tc m -MIBI imaging and tumor marker detection had no significance difference(P > 0.05). Conclusion: 99 Tc m -MIBI imaging combined with serum tumor markers has great clinical significance in identifying pulmonary nodules. (authors)

  8. Development of a combined ultrasound and electrical impedance imaging system for prostate cancer detection

    Science.gov (United States)

    Wan, Yuqing

    Approximately 240,890 men were diagnosed with prostate cancer and 33,720 men were expected to die from it in the year of 2011 in the United States. Unfortunately, the current clinical diagnostic methods (e.g. prostate-specific antigen (PSA), digital rectal examination, ultrasound guided biopsy) used for detecting and staging prostate cancer are limited. It has been shown that cancerous prostate tissue has significantly different electrical properties when compared to benign tissues. Based on these electrical property findings, a transrectal electrical impedance tomography (TREIT) system is proposed as a novel prostate imaging modality. An ultrasound probe is incorporated with TREIT to achieve anatomic information of the prostate and guide electrical property reconstruction. Without the guidance of the ultrasound, the TREIT system can easily discern high contrast inclusions of 1 cm in diameter at distances centered at two times the radius of the TREIT probe away from the probe surface. Furthermore, we have demonstrated that our system is able to detect low contrast inclusions. With the guidance of the ultrasound, our system is capable of detecting a plastic inclusion embedded in a gelatin phantom, indicating the potential to detect cancer. In addition, the results of preliminary in vivo clinical trials using the imaging system are also presented in the thesis. After collecting data for a total 66 patients, we demonstrated that the in vivo conductivity of cancerous tissue is significantly greater than that of benign tissue (p=0.0015 at 400 Hz) and the conductivity of BPH tissue is significantly lower than that of normal tissue (p=0.0009 at 400 Hz). Additionally at 25.6 kHz, the dual-modal imaging system is able to differentiate cancerous tissue from benign tissue with sensitivity of 0.6012 and specificity of 0.5498, normal tissue from BPH tissue with sensitivity of 0.6085 and specificity of 0.5813 and differentiate cancerous tissue from BPH tissue with sensitivity of

  9. Combined Raman spectroscopy and autofluoresence imaging method for in vivo skin tumor diagnosis

    Science.gov (United States)

    Zakharov, V. P.; Bratchenko, I. A.; Myakinin, O. O.; Artemyev, D. N.; Khristoforova, Y. A.; Kozlov, S. V.; Moryatov, A. A.

    2014-09-01

    The fluorescence and Raman spectroscopy (RS) combined method of in vivo detection of malignant human skin cancer was demonstrated. The fluorescence analysis was used for detection of abnormalities during fast scanning of large tissue areas. In suspected cases of malignancy the Raman spectrum analysis of biological tissue was performed to determine the type of neoplasm. A special RS phase method was proposed for in vivo identification of skin tumor. Quadratic Discriminant Analysis was used for tumor type classification on phase planes. It was shown that the application of phase method provides a diagnosis of malignant melanoma with a sensitivity of 89% and a specificity of 87%.

  10. Combined analysis of cervical smears. Cytopathology, image cytometry and in situ hybridization.

    Science.gov (United States)

    Multhaupt, H; Bruder, E; Elit, L; Rothblat, I; Warhol, M

    1993-01-01

    This study was an attempt to correlate the Bethesda System of Papanicolaou smear classification with DNA content by image analysis and the presence of human papillomavirus (HPV) as determined by in situ hybridization. DNA histograms were classified as normal diploid, diploid proliferative, polyploid and aneuploid. HPV in situ hybridization was performed with a cocktail of probes specific to HPV types 6, 11, 16 and 18. There was a good correlation between normal cytology and normal DNA histograms. Cytologically normal smears with bacterial or fungal infections showed a high proliferation index. HPV infection correlated with DNA polyploidy but was seen in 15 of 29 smears classified as cytologically normal. Morphologically abnormal Papanicolaou smears correlated with aneuploid DNA content. Smears classified as intraepithelial neoplasia correlated with aneuploid DNA content in all 12 cases. Four of five cases cytologically suspicious for HPV infection had HPV by in situ hybridization.

  11. Study of ancient Islamic gilded pieces combining PIXE-RBS on external microprobe with sem images

    International Nuclear Information System (INIS)

    Ynsa, M.D.; Gutierrez, P.C.; Enguita, O.; Chamon, J.; Pardo, A.I.; Arroyo, M.; Barrio, J.; Gomez-Morilla, I.; Ferretti, M.; Climent-Font, A.

    2008-01-01

    Numerous metallic objects with very aesthetic and technological qualities have been recovered by archaeological excavations. Adequate processes of restoration and conservation treatments require the accurate determination of the elemental composition and distribution within the objects, as well as the identification of the nature and distribution of the corrosion products. Ideally the identification method should cause no alteration in the sample. In this work, different archaeological pieces with a gilded look have been characterized using simultaneously PIXE and RBS at the CMAM external microprobe in order to study the gilding metalworking done in the Iberian Peninsula during the Middle Ages. The gold layer thickness and its elemental concentrations of Ag, Au and Hg were determined by both techniques and compared with the scanning electron microscopy images obtained for some fragments of pieces. (orig.)

  12. A Hybrid Approach to Simulate X-Ray Imaging Techniques, Combining Monte Carlo and Deterministic Algorithms

    Science.gov (United States)

    Freud, N.; Letang, J.-M.; Babot, D.

    2005-10-01

    In this paper, we propose a hybrid approach to simulate multiple scattering of photons in objects under X-ray inspection, without recourse to parallel computing and without any approximation sacrificing accuracy. Photon scattering is considered from two points of view: it contributes to X-ray imaging and to the dose absorbed by the patient. The proposed hybrid approach consists of a Monte Carlo stage followed by a deterministic phase, thus taking advantage of the complementarity between these two methods. In the first stage, a set of scattering events occurring in the inspected object is determined by means of classical Monte Carlo simulation. Then this set of scattering events is used to compute the energy imparted to the detector, with a deterministic algorithm based on a "forced detection" scheme. Regarding dose evaluation, we propose to assess separately the energy deposited by direct radiation (using a deterministic algorithm) and by scattered radiation (using our hybrid approach). The results obtained in a test case are compared to those obtained with the Monte Carlo method alone (Geant4 code) and found to be in excellent agreement. The proposed hybrid approach makes it possible to simulate the contribution of each type (Compton or Rayleigh) and order of scattering, separately or together, with a single PC, within reasonable computation times (from minutes to hours, depending on the required detector resolution and statistics). It is possible to simulate radiographic images virtually free from photon noise. In the case of dose evaluation, the hybrid approach appears particularly suitable to calculate the dose absorbed by regions of interest (rather than the entire irradiated organ) with computation time and statistical fluctuations considerably reduced in comparison with conventional Monte Carlo simulation.

  13. Combining transcranial magnetic stimulation and functional imaging in cognitive brain research: possibilities and limitations.

    Science.gov (United States)

    Sack, Alexander T; Linden, David E J

    2003-09-01

    Transcranial magnetic stimulation (TMS) is a widely used tool for the non-invasive study of basic neurophysiological processes and the relationship between brain and behavior. We review the physical and physiological background of TMS and discuss the large body of perceptual and cognitive studies, mainly in the visual domain, that have been performed with TMS in the past 15 years. We compare TMS with other neurophysiological and neuropsychological research tools and propose that TMS, compared with the classical neuropsychological lesion studies, can make its own unique contribution. As the main focus of this review, we describe the different approaches of combining TMS with functional neuroimaging techniques. We also discuss important shortcomings of TMS, especially the limited knowledge concerning its physiological effects, which often make the interpretation of TMS results ambiguous. We conclude with a critical analysis of the resulting conceptual and methodological limitations that the investigation of functional brain-behavior relationships still has to face. We argue that while some of the methodological limitations of TMS applied alone can be overcome by combination with functional neuroimaging, others will persist until its physical and physiological effects can be controlled.

  14. Unmanned Aerial Systems for Monitoring Trace Tropospheric Gases

    Directory of Open Access Journals (Sweden)

    Travis J. Schuyler

    2017-10-01

    Full Text Available The emission of greenhouse gases (GHGs has changed the composition of the atmosphere during the Anthropocene. Accurately documenting the sources and magnitude of GHGs emission is an important undertaking for discriminating the contributions of different processes to radiative forcing. Currently there is no mobile platform that is able to quantify trace gases at altitudes <100 m above ground level that can achieve spatiotemporal resolution on the order of meters and seconds. Unmanned aerial systems (UASs can be deployed on-site in minutes and can support the payloads necessary to quantify trace gases. Therefore, current efforts combine the use of UASs available on the civilian market with inexpensively designed analytical systems for monitoring atmospheric trace gases. In this context, this perspective introduces the most relevant classes of UASs available and evaluates their suitability to operate three kinds of detectors for atmospheric trace gases. The three subsets of UASs discussed are: (1 micro aerial vehicles (MAVs; (2 vertical take-off and landing (VTOL; and, (3 low-altitude short endurance (LASE systems. The trace gas detectors evaluated are first the vertical cavity surface emitting laser (VCSEL, which is an infrared laser-absorption technique; second two types of metal-oxide semiconductor sensors; and, third a modified catalytic type sensor. UASs with wingspans under 3 m that can carry up to 5 kg a few hundred meters high for at least 30 min provide the best cost and convenience compromise for sensors deployment. Future efforts should be focused on the calibration and validation of lightweight analytical systems mounted on UASs for quantifying trace atmospheric gases. In conclusion, UASs offer new and exciting opportunities to study atmospheric composition and its effect on weather patterns and climate change.

  15. Use of digital image analysis combined with fractal theory to determine particle morphology and surface texture of quartz sands

    Directory of Open Access Journals (Sweden)

    Georgia S. Araujo

    2017-12-01

    Full Text Available The particle morphology and surface texture play a major role in influencing mechanical and hydraulic behaviors of sandy soils. This paper presents the use of digital image analysis combined with fractal theory as a tool to quantify the particle morphology and surface texture of two types of quartz sands widely used in the region of Vitória, Espírito Santo, southeast of Brazil. The two investigated sands are sampled from different locations. The purpose of this paper is to present a simple, straightforward, reliable and reproducible methodology that can identify representative sandy soil texture parameters. The test results of the soil samples of the two sands separated by sieving into six size fractions are presented and discussed. The main advantages of the adopted methodology are its simplicity, reliability of the results, and relatively low cost. The results show that sands from the coastal spit (BS have a greater degree of roundness and a smoother surface texture than river sands (RS. The values obtained in the test are statistically analyzed, and again it is confirmed that the BS sand has a slightly greater degree of sphericity than that of the RS sand. Moreover, the RS sand with rough surface texture has larger specific surface area values than the similar BS sand, which agree with the obtained roughness fractal dimensions. The consistent experimental results demonstrate that image analysis combined with fractal theory is an accurate and efficient method to quantify the differences in particle morphology and surface texture of quartz sands.

  16. The Simultaneous Combination of Phase Contrast Imaging with In Situ X-ray diffraction from Shock Compressed Matter

    Science.gov (United States)

    McBride, Emma Elizabeth; Seiboth, Frank; Cooper, Leora; Frost, Mungo; Goede, Sebastian; Harmand, Marion; Levitan, Abe; McGonegle, David; Miyanishi, Kohei; Ozaki, Norimasa; Roedel, Melanie; Sun, Peihao; Wark, Justin; Hastings, Jerry; Glenzer, Siegfried; Fletcher, Luke

    2017-10-01

    Here, we present the simultaneous combination of phase contrast imaging (PCI) techniques with in situ X-ray diffraction to investigate multiple-wave features in laser-driven shock-compressed germanium. Experiments were conducted at the Matter at Extreme Conditions end station at the LCLS, and measurements were made perpendicular to the shock propagation direction. PCI allows one to take femtosecond snapshots of magnified real-space images of shock waves as they progress though matter. X-ray diffraction perpendicular to the shock propagation direction provides the opportunity to isolate and identify different waves and determine the crystal structure unambiguously. Here, we combine these two powerful techniques simultaneously, by using the same Be lens setup to focus the fundamental beam at 8.2 keV to a size of 1.5 mm on target for PCI and the 3rd harmonic at 24.6 keV to a spot size of 2 um on target for diffraction.

  17. Cervical spine imaging in trauma: Does the use of grid and filter combination improve visualisation of the cervicothoracic junction?

    Energy Technology Data Exchange (ETDEWEB)

    Goyal, Nimit, E-mail: nimitgoyal@doctors.org.u [University Hospital of Wales, Heath Park, Cardiff, CF14 4XW (United Kingdom); Rachapalli, Vamsidhar; Burns, Helen; Lloyd, David C.F. [University Hospital of Wales, Heath Park, Cardiff, CF14 4XW (United Kingdom)

    2011-02-15

    Purpose: To evaluate the usefulness of filter and anti-scatter grid combination in demonstrating the cervicothoracic junction in lateral cervical spine radiographs performed for trauma patients. Methods: Following a change in departmental protocol in our hospital, anti-scatter grid and filter are routinely used for lateral cervical spine radiograph in all trauma patients with immobilised cervical spine. A retrospective study was done to compare the efficacy of lateral cervical spine radiographs in demonstrating the cervicothoracic junction for a period of three months before and after the implementation of the change. All images were independently evaluated by two observers. Results: 253 trauma patients had a lateral cervical spine radiograph done in January to March 2003 without using the anti-scatter grid and filter while 309 patients in January to March 2007, using filter and grid. Inter-observer variability between the two observers was calculated using Cohen's Kappa which showed good and very good agreement for 2003 and 2007 respectively. 126 (49.8%) images adequately demonstrated the cervicothoracic junction without using filter and grid while 189 (61.1%) were adequate following their use. This was statistically significant (Fischer exact test, p value = 0.0081). Conclusion: The use of filter and anti-scatter grids improves the visualisation of cervicothoracic junction in lateral cervical spine imaging and reduces the need to repeat exposure.

  18. Object-Oriented Semisupervised Classification of VHR Images by Combining MedLDA and a Bilateral Filter

    Directory of Open Access Journals (Sweden)

    Shi He

    2015-01-01

    Full Text Available A Bayesian hierarchical model is presented to classify very high resolution (VHR images in a semisupervised manner, in which both a maximum entropy discrimination latent Dirichlet allocation (MedLDA and a bilateral filter are combined into a novel application framework. The primary contribution of this paper is to nullify the disadvantages of traditional probabilistic topic models on pixel-level supervised information and to achieve the effective classification of VHR remote sensing images. This framework consists of the following two iterative steps. In the training stage, the model utilizes the central labeled pixel and its neighborhood, as a squared labeled image object, to train the classifiers. In the classification stage, each central unlabeled pixel with its neighborhood, as an unlabeled object, is classified as a user-provided geoobject class label with the maximum posterior probability. Gibbs sampling is adopted for model inference. The experimental results demonstrate that the proposed method outperforms two classical SVM-based supervised classification methods and probabilistic-topic-models-based classification methods.

  19. Combination of optoacoustics and ultrasound imaging for non-invasive, rapid assessment, and management of circulatory shock

    Science.gov (United States)

    Petrov, Yuriy; Petrov, Irene Y.; Esenaliev, Rinat O.; Kinsky, Michael; Prough, Donald S.

    2011-03-01

    We developed a noninvasive, optoacoustic diagnostic platform for monitoring of multiple physiologic variables in inpatients and outpatients. One of the most important applications of this platform is noninvasive, rapid assessment and management of circulatory shock, a common condition in critically ill patients. At present, monitoring of circulatory shock requires measurement of central venous blood oxygenation using invasive procedures such as insertion of catheters in central veins. Hemoglobin saturation below 70% in central veins indicates circulatory shock that requires immediate treatment. We built a portable optoacoustic system for noninvasive measurement of central venous oxygenation. In this study we used the optoacoustic system and clinical ultrasound imaging systems for rapid optoacoustic probing of these veins. The optoacoustic system utilizes a custom-made, sensitive optoacoustic probe that was developed in our laboratory for monitoring of blood oxygenation in deep blood vessels. The studies were performed in human subjects with different geometry (depth, size) of the veins. The ultrasound imaging systems permitted rapid identification of specific blood vessels for optoacoustic probing. We developed a novel algorithm for continuous, realtime, and precise measurement of blood oxygenation in blood vessels. Precision of central venous oxygenation measurement obtained in the study was very high: 1%. Our results indicate that the combination of optoacoustics and ultrasound imaging systems can provide more rapid and accurate assessment and management of the circulatory shock.

  20. Workflow optimisation for multimodal imaging procedures: a case of combined X-ray and MRI-guided TACE.

    Science.gov (United States)

    Fernández-Gutiérrez, Fabiola; Wolska-Krawczyk, Malgorzata; Buecker, Arno; Houston, J Graeme; Melzer, Andreas

    2017-02-01

    This study presents a framework for workflow optimisation of multimodal image-guided procedures (MIGP) based on discrete event simulation (DES). A case of a combined X-Ray and magnetic resonance image-guided transarterial chemoembolisation (TACE) is presented to illustrate the application of this method. We used a ranking and selection optimisation algorithm to measure the performance of a number of proposed alternatives to improve a current scenario. A DES model was implemented with detail data collected from 59 TACE procedures and durations of magnetic resonance imaging (MRI) diagnostic procedures usually performed in a common MRI suite. Fourteen alternatives were proposed and assessed to minimise the waiting times and improve workflow. Data analysis observed an average of 20.68 (7.68) min of waiting between angiography and MRI for TACE patients in 71.19% of the cases. Following the optimisation analysis, an alternative was identified to reduce waiting times in angiography suite up to 48.74%. The model helped to understand and detect 'bottlenecks' during multimodal TACE procedures, identifying a better alternative to the current workflow and reducing waiting times. Simulation-based workflow analysis provides a cost-effective way to face some of the challenges of introducing MIGP in clinical radiology, highligthed in this study.

  1. Combining satellite and seismic images to analyse the shallow structure of the Dead Sea Transform near the DESERT transect

    Science.gov (United States)

    Kesten, D.; Weber, M.; Haberland, Ch.; Janssen, Ch.; Agnon, A.; Bartov, Y.; Rabba, I.

    2008-02-01

    The left-lateral Dead Sea Transform (DST) in the Middle East is one of the largest continental strike-slip faults of the world. The southern segment of the DST in the Arava/Araba Valley between the Dead Sea and the Red Sea, called Arava/Araba Fault (AF), has been studied in detail in the multidisciplinary DESERT (DEad SEa Rift Transect) project. Based on these results, here, the interpretations of multi-spectral (ASTER) satellite images and seismic reflection studies have been combined to analyse geologic structures. Whereas satellite images reveal neotectonic activity in shallow young sediments, reflection seismic image deep faults that are possibly inactive at present. The combination of the two methods allows putting some age constraint on the activity of individual fault strands. Although the AF is clearly the main active fault segment of the southern DST, we propose that it has accommodated only a limited (up to 60 km) part of the overall 105 km of sinistral plate motion since Miocene times. There is evidence for sinistral displacement along other faults, based on geological studies, including satellite image interpretation. Furthermore, a subsurface fault is revealed ≈4 km west of the AF on two ≈E-W running seismic reflection profiles. Whereas these seismic data show a flower structure typical for strike-slip faults, on the satellite image this fault is not expressed in the post-Miocene sediments, implying that it has been inactive for the last few million years. About 1 km to the east of the AF another, now buried fault, was detected in seismic, magnetotelluric and gravity studies of DESERT. Taking together various evidences, we suggest that at the beginning of transform motion deformation occurred in a rather wide belt, possibly with the reactivation of older ≈N-S striking structures. Later, deformation became concentrated in the region of today’s Arava Valley. Till ≈5 Ma ago there might have been other, now inactive fault traces in the vicinity

  2. Mitosis detection in breast cancer pathology images by combining handcrafted and convolutional neural network features

    Science.gov (United States)

    Wang, Haibo; Cruz-Roa, Angel; Basavanhally, Ajay; Gilmore, Hannah; Shih, Natalie; Feldman, Mike; Tomaszewski, John; Gonzalez, Fabio; Madabhushi, Anant

    2014-01-01

    Abstract. Breast cancer (BCa) grading plays an important role in predicting disease aggressiveness and patient outcome. A key component of BCa grade is the mitotic count, which involves quantifying the number of cells in the process of dividing (i.e., undergoing mitosis) at a specific point in time. Currently, mitosis counting is done manually by a pathologist looking at multiple high power fields (HPFs) on a glass slide under a microscope, an extremely laborious and time consuming process. The development of computerized systems for automated detection of mitotic nuclei, while highly desirable, is confounded by the highly variable shape and appearance of mitoses. Existing methods use either handcrafted features that capture certain morphological, statistical, or textural attributes of mitoses or features learned with convolutional neural networks (CNN). Although handcrafted features are inspired by the domain and the particular application, the data-driven CNN models tend to be domain agnostic and attempt to learn additional feature bases that cannot be represented through any of the handcrafted features. On the other hand, CNN is computationally more complex and needs a large number of labeled training instances. Since handcrafted features attempt to model domain pertinent attributes and CNN approaches are largely supervised feature generation methods, there is an appeal in attempting to combine these two distinct classes of feature generation strategies to create an integrated set of attributes that can potentially outperform either class of feature extraction strategies individually. We present a cascaded approach for mitosis detection that intelligently combines a CNN model and handcrafted features (morphology, color, and texture features). By employing a light CNN model, the proposed approach is far less demanding computationally, and the cascaded strategy of combining handcrafted features and CNN-derived features enables the possibility of maximizing the

  3. Distinguishing sliding area by decision analyzing with remote sensing image and lidar data combined

    Science.gov (United States)

    Chang, Chia-Hao; Wu, Jee-Cheng

    2017-10-01

    Every year people in Taiwan have been facing earthquake and typhoon nature disaster challenges which are seriously affecting the people's lives and property. During summer season typhoons bring abundant rainfall resulting in landslides and debris flows. Because the landslide attributes to several environmental factors, we could monitor and analyze endangered areas to prevent damages. In this study Taiwan Provincial Highway 14 branch at 34K 38K+500m is chosen, which has devastated by Earthquake 921 and Typhoon Mindulle. A decision analysis is conducted by utilizing combined ortho-photo and LiDAR Digital Elevation Model (DEM) data to classify landslide areas. The result showed that the performance of overall accuracy could be increased when terrain factors are considered.

  4. Combined Application of X-Ray and Neutron Imaging Techniques to Wood Materials

    Directory of Open Access Journals (Sweden)

    Roberto Triolo

    2010-12-01

    Full Text Available Conservation of Cultural Heritage is extremely important not only from a cultural point of view, but also from a practical one. It is our duty to pass on to future generations the cultural heritage left tous by our ancestors. Wood is one of the most common materials used to generate works of art which are in a state of constant change and/or deterioration. In order to optimize the knowledge of artworks together with their conservation, it is necessary to use the most advanced scientific and technological tools. In the following paper, we will show the results which can be achieved by application of complementary techniques based on the combined use of X-rays and neutrons as structural probes.

  5. Combined Optogenetics and Voltage Sensitive Dye Imaging at Single Cell Resolution

    Directory of Open Access Journals (Sweden)

    Silvia eWilladt

    2014-10-01

    Full Text Available Information processing in the central nervous system makes use of densely woven networks of neurons with complex dendritic and axonal arborizations. Studying signaling in such a network requires precise control over the activity of specific neurons and an understanding how the synaptic signals are integrated. We established a system using a recently published red-shifted voltage sensitive dye in slices from mice expressing channelrhodopsin in GABAergic neurons. Using a focused 473 nm laser for channelrhodopsin activation and 635 nm laser wide field illumination for voltage sensitive dye excitation we were able to simultaneously measure dendritic voltage transients and stimulate inhibitory synaptic connections. The combination of these techniques provides excellent spatiotemporal control over neuron activation and high resolution information on dendritic signal processing.

  6. Modeling Soil Organic Carbon at Regional Scale by Combining Multi-Spectral Images with Laboratory Spectra

    DEFF Research Database (Denmark)

    Peng, Yi; Xiong, Xiong; Adhikari, Kabindra

    2015-01-01

    the model developed from only RS data and ancillary environmental data (RMSE: 3.6%, R2: 0.46). Plant-available water (PAW) was the most important predictor for all the models because of its close relationship with soil organic matter content. Moreover, vegetation indices, such as the Normalized Difference......There is a great challenge in combining soil proximal spectra and remote sensing spectra to improve the accuracy of soil organic carbon (SOC) models. This is primarily because mixing of spectral data from different sources and technologies to improve soil models is still in its infancy. The first...... parameters and soil maps were compiled to predict topsoil SOC using Cubist regression and Bayesian kriging. The results showed that the model developed from RS data, ancillary environmental data and laboratory spectral data yielded a lower root mean square error (RMSE) (2.8%) and higher R2 (0.59) than...

  7. Combined fuzzy logic and random walker algorithm for PET image tumor delineation.

    Science.gov (United States)

    Soufi, Motahare; Kamali-Asl, Alireza; Geramifar, Parham; Abdoli, Mehrsima; Rahmim, Arman

    2016-02-01

    The random walk (RW) technique serves as a powerful tool for PET tumor delineation, which typically involves significant noise and/or blurring. One challenging step is hard decision-making in pixel labeling. Fuzzy logic techniques have achieved increasing application in edge detection. We aimed to combine the advantages of fuzzy edge detection with the RW technique to improve PET tumor delineation. A fuzzy inference system was designed for tumor edge detection from RW probabilities. Three clinical PET/computed tomography datasets containing 12 liver, 13 lung, and 18 abdomen tumors were analyzed, with manual expert tumor contouring as ground truth. The standard RW and proposed combined method were compared quantitatively using the dice similarity coefficient, the Hausdorff distance, and the mean standard uptake value. The dice similarity coefficient of the proposed method versus standard RW showed significant mean improvements of 21.0±7.2, 12.3±5.8, and 18.4%±6.1% for liver, lung, and abdominal tumors, respectively, whereas the mean improvements in the Hausdorff distance were 3.6±1.4, 1.3±0.4, 1.8±0.8 mm, and the mean improvements in SUVmean error were 15.5±6.3, 11.7±8.6, and 14.1±6.8% (all P's<0.001). For all tumor sizes, the proposed method outperformed the RW algorithm. Furthermore, tumor edge analysis demonstrated further enhancement of the performance of the algorithm, relative to the RW method, with decreasing edge gradients. The proposed technique improves PET lesion delineation at different tumor sites. It depicts greater effectiveness in tumors with smaller size and/or low edge gradients, wherein most PET segmentation algorithms encounter serious challenges. Favorable execution time and accurate performance of the algorithm make it a great tool for clinical applications.

  8. Combination of Magnetic Resonance Imaging and Electrophysiological Studies in Lumbar Disc Herniation.

    Science.gov (United States)

    Zhong, Wenxiang; Wang, Jichao; Zhang, Wenchuan; Liu, Pengfei; Visocchi, Massimiliano; Li, Shi-Ting

    2017-01-01

    Objective We aimed to study the clinical value of magnetic resonance imaging (MRI) and electrophysiological studies in the diagnosis of lumbar disc herniation and in the evaluation of the therapeutic effect of discectomy. Methods In this study, 265 patients with LDH were treated with discectomy after assessment by the Japanese Orthopedic Association (JOA) score, MRI, and electrophysiological studies. All the patients were followed-up for 6 years. The effects of the operation were assessed by determining the angle between the nerve root canal and disc protrusion (AN value), the stenotic ratio of the spinal canal, the width of the lateral recess, motor conduction velocity (MCV), sensory conduction velocity (SCV), and nerve action potential (NAP) before and after operation. Results The AN value, stenotic ratio of the spinal canal, and the width of the lateral recess of protruding intervertebral discs showed significant differences from these values for the patients' unaffected intervertebral discs (P disc herniation, and in the evaluation of the effect of surgery.

  9. Combined small and large bowel MR imaging in patients with Crohn's disease: a feasibility study

    International Nuclear Information System (INIS)

    Narin, Burcu; Ajaj, Waleed; Goehde, Susanne; Lauenstein, Thomas C.; Langhorst, Jost; Gerken, Guido; Akgoez, Haldun; Ruehm, Stefan G.

    2004-01-01

    MRI of the small bowel is a new method for the assessment of inflammatory bowel diseases. However, inflammatory bowel disease can affect both the small and large bowel. Therefore, our goal was to assess the feasibility of displaying the small bowel and colon simultaneously by MR imaging. Eighteen patients with inflammatory bowel disease were studied. For small bowel distension, patients ingested a solution containing mannitol and locust bean gum. Furthermore, the colon was rectally filled with water. MR examinations were performed on a 1.5-T system. Before and after intravenous gadolinium administration, a T1w data set was collected. All patients underwent conventional colonoscopy as a standard of reference. The oral ingestion and the rectal application of water allowed an assessment of the small bowel and colon in all patients. By means of MRI (endoscopy), 19 (13) inflamed bowel segments in the colon and terminal ileum were detected. Furthermore, eight additional inflammatory lesions in the jejunum and proximal ileum that had not been endoscopically accessible were found by MRI. The simultaneous display of the small and large bowel by MRI is feasible. Major advantages of the proposed MR concept are related to its non-invasive character as well as to the potential to visualize parts of the small bowel that cannot be reached by endoscopy. (orig.)

  10. Quantitative analysis of bowel gas by plain abdominal radiograph combined with computer image processing

    International Nuclear Information System (INIS)

    Gao Yan; Peng Kewen; Zhang Houde; Shen Bixian; Xiao Hanxin; Cai Juan

    2003-01-01

    Objective: To establish a method for quantitative analysis of bowel gas by plain abdominal radiograph and computer graphics. Methods: Plain abdominal radiographs in supine position from 25 patients with irritable bowel syndrome (IBS) and 20 health controls were studied. A gastroenterologist and a radiologist independently conducted the following procedure on each radiograph. After the outline of bowel gas was traced by axe pen, the radiograph was digitized by a digital camera and transmitted to the computer with Histogram software. The total gas area was determined as the pixel value on images. The ratio of the bowel gas quantity to the pixel value in the region surrounded by a horizontal line tangential to the superior pubic symphysis margin, a horizontal line tangential to the tenth dorsal vertebra inferior margin, and the lateral line tangential to the right and left anteriosuperior iliac crest, was defined as the gas volume score (GVS). To examine the sequential reproducibility, a second plain abdominal radiograph was performed in 5 normal controls 1 week later, and the GVS were compared. Results: Bowel gas was easily identified on the plain abdominal radiograph. Both large and small intestine located in the selected region. Both observers could finish one radiographic measurement in less than 10 mins. The correlation coefficient between the two observers was 0.986. There was no statistical difference on GVS between the two sequential radiographs in 5 health controls. Conclusion: Quantification of bowel gas based on plain abdominal radiograph and computer is simple, rapid, and reliable

  11. A Method for Combined Retinal Vascular and Tissue Oxygen Tension Imaging.

    Science.gov (United States)

    Felder, Anthony E; Wanek, Justin; Tan, Michael R; Blair, Norman P; Shahidi, Mahnaz

    2017-09-06

    The retina requires adequate oxygenation to maintain cellular metabolism and visual function. Inner retinal oxygen metabolism is directly related to retinal vascular oxygen tension (PO 2 ) and inner retinal oxygen extraction fraction (OEF), whereas outer retinal oxygen consumption (QO 2 ) relies on oxygen availability by the choroid and is contingent upon retinal tissue oxygen tension (tPO 2 ) gradients across the retinal depth. Thus far, these oxygenation and metabolic parameters have been measured independently by different techniques in separate animals, precluding a comprehensive and correlative assessment of retinal oxygenation and metabolism dynamics. The purpose of the current study is to report an innovative optical system for dual oxyphor phosphorescence lifetime imaging to near-simultaneously measure retinal vascular PO 2 and tPO 2 in rats. The use of a new oxyphor with different spectral characteristics allowed differentiation of phosphorescence signals from the retinal vasculature and tissue. Concurrent measurements of retinal arterial and venous PO 2 , tPO 2 through the retinal depth, inner retinal OEF, and outer retinal QO 2 were demonstrated, permitting a correlative assessment of retinal oxygenation and metabolism. Future application of this method can be used to investigate the relations among retinal oxygen content, extraction and metabolism under pathologic conditions and thus advance knowledge of retinal hypoxia pathophysiology.

  12. Feasibility of the combination of 3D CTA and 2D CT imaging guidance for clipping microsurgery of anterior communicating artery aneurysm.

    Science.gov (United States)

    Wada, Kojiro; Nawashiro, Hiroshi; Ohkawa, Hidenori; Arimoto, Hirohiko; Takeuchi, Satoru; Mori, Kentaro

    2015-04-01

    We report the technique of three-dimensional computed tomography angiography (3D CTA)+two-dimensional computed tomographic (2D CT) imaging as an adjunct in early surgery for a ruptured anterior communicating artery (ACoA) aneurysm by adopting an anterior interhemispheric approach. These combined imaging modalities provide accurate intraoperative anatomical information. To produce images for an anterior interhemispheric approach, 3D CTA+2D coronal CT images, which are perpendicular to the direction of the surgical approach at three levels (brain surface, genu of the corpus callosum and aneurysm neck), were constructed. We also produced two 3D CTA+2D CT images of the lamina terminalis, with a horizontal 10-degree difference, to clarify the vascular architecture around the aneurysm stereotactically, as well as the dissection point and direction to open the lamina terminalis. Furthermore, we produced a 3D CTA+2D sagittal CT image at the midline, which allowed us to understand the anatomical architecture of the aneurysm, planum sphenoidale and tuberculum sellae. In addition, four different 3D CTA aneurysm images were produced for deciding the clip size preoperatively. The imaging findings in 28 patients with 28 ACoA aneurysms facilitated early clipping. Based on these 3D CTA+2D CT images, we conducted aneurysm surgery, and successfully performed neck clipping via an anterior interhemispheric approach. The combination of 3D CTA and 2D CT images is a feasible and useful method of image guidance for ACoA aneurysm microsurgery.

  13. Chitosan Combined with Molecular Beacon for Mir-155 Detection and Imaging in Lung Cancer

    Directory of Open Access Journals (Sweden)

    Hai-Zhen Zhu

    2014-09-01

    Full Text Available Lung cancer is the major cause of cancer-related deaths worldwide, thus developing effective methods for its early diagnosis is urgently needed. In recent years, microRNAs (miRNAs, miR have been reported to play important roles in carcinogenesis and have become potential biomarkers for cancer diagnosis and treatment. Molecular beacon (MB technology is a universal technology to detect DNA/RNA expression in living cells. As a natural polymers, chitosan (CS nanoparticles could be used as a carrier for safe delivery of nucleic acid. In this study, we developed a probe using nanoparticles of miR-155 MB self assembled with CS (CS-miR-155 MB to image the expression of miR-155 in cancer cells. Hybridization assay showed that the locked nucleic acid (LAN modified miR-155 MB could target miR-155 effectively and sensitively. The miR-155 MB self-assembly with CS nanoparticles formed stable complexes at the proper weight ratio. The CS nanoparticles showed higher fluorescence intensity and transfection efficiency than the lipid-based formulation transfection agent by confocal microscopy and flow cytometry analysis. The CS-MB complexes were found to be easily synthesized and exhibited strong enzymatic stability, efficient cellular uptake, high target selectivity and biocompatibility. The CS-MB complexes can also be applied in other cancers just by simply changing for a targeted miRNA highly expressed in those cancer cells. Therefore, it is a promising vehicle used for detecting miRNA expression in living cells.

  14. Combined structural and functional imaging reveals cortical deactivations in grapheme-colour synaesthesia

    Directory of Open Access Journals (Sweden)

    Erik eO'Hanlon

    2013-10-01

    Full Text Available Synaesthesia is a heritable condition in which particular stimuli generate specific and consistent sensory percepts or associations in another modality or processing stream. Functional neuroimaging studies have identified potential correlates of these experiences, including, in some but not all cases, the hyperactivation of visuotemporal areas and of parietal areas thought to be involved in perceptual binding. Structural studies have identified a similarly variable spectrum of differences between synaesthetes and controls. However, it remains unclear the extent to which these neural correlates reflect the synaesthetic experience itself or additional phenotypes associated with the condition. Here, we acquired both structural and functional neuroimaging data comparing thirteen grapheme-colour synaesthetes with eleven non-synaesthetes. Using voxel-based morphometry and diffusion tensor imaging, we identify a number of clusters of increased volume of grey matter, of white matter or of increased fractional anisotropy in synaesthetes versus controls. To assess the possible involvement of these areas in the synaesthetic experience, we used nine areas of increased grey matter volume as regions of interest in an fMRI experiment that characterised the contrast in response to stimuli which induced synaesthesia (i.e. letters versus those which did not (non-meaningful symbols. Two of these areas, in left lateral occipital cortex and in postcentral gyrus, showed sensitivity to this contrast in synaesthetes but not controls. Unexpectedly, in both regions, the letter stimuli produced a strong negative BOLD signal in synaesthetes. An additional whole-brain fMRI analysis identified fourteen areas, three of which were driven mainly by a negative BOLD response to letters in synaesthetes. Our findings suggest that cortical deactivations may be involved in the conscious experience of internally generated synaesthetic percepts

  15. Multimodal MRI in the characterization of glial neoplasms: the combined role of single-voxel MR spectroscopy, diffusion imaging and echo-planar perfusion imaging

    International Nuclear Information System (INIS)

    Zonari, Paolo; Baraldi, Patrizia; Crisi, Girolamo

    2007-01-01

    Diffusion-weighted imaging (DWI), perfusion-weighted imaging (PWI) and MR spectroscopy (MRS) provide useful data for tumor evaluation. To assess the contribution of these multimodal techniques in grading glial neoplasms, we compared the value of DWI, PWI and MRS in the evaluation of histologically proven high- and low-grade gliomas in a population of 105 patients. Independently for each modality, the following variables were used to compare the tumors: minimum apparent diffusion coefficient (ADC) and maximum relative cerebral blood volume (rCBV) normalized values between tumor and healthy tissue, maximum Cho/Cr ratio and minimum NAA/Cr ratio in tumor, and scored lactate and lipid values in tumor. The Mann-Whitney and Wilcoxon tests were employed to compare DWI, PWI and MRS between tumor types. Logistic regression analysis was used to determine which parameters best increased the diagnostic accuracy in terms of sensitivity, specificity, and positive and negative predictive values. ROC curves were determined for parameters with high sensitivity and specificity to identify threshold values to separate high- from low-grade lesions. Statistically significant differences were found for rCBV tumor/normal tissue ratio, and NAA/Cr ratio in tumor and Cho/Cr ratio in tumor between low- and high-grade tumors. The best performing single parameter for group classification was the normalized rCBV value; including all parameters, statistical significance was reached by rCBV tumor/normal tissue ratio, NAA/Cr tumor ratio and lactate. From the ROC curves, a high probability for a neoplasm to be a high-grade lesion was associated with a rCBV tumor/normal tissue ratio of >1.16 and NAA/Cr tumor ratio of <0.44. Combining PWI and MRS with conventional MR imaging increases the accuracy of the attribution of malignancy to glial neoplasms. The best performing parameter was found to be the perfusion level. (orig.)

  16. Multimodal MRI in the characterization of glial neoplasms: the combined role of single-voxel MR spectroscopy, diffusion imaging and echo-planar perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Zonari, Paolo [Ospedale ' ' B. Ramazzini' ' , AUSL Modena, Neuroradiologia, Dipartimento Integrato di Neuroscienze, Carpi, Modena (Italy); Baraldi, Patrizia [Universita degli Studi di Modena e Reggio Emilia, Dipartimento di Scienze Biomediche, Sezione di Fisiologia, Modena (Italy); Crisi, Girolamo [Azienda Ospedaliero-Universitaria di Parma, Dipartimento ad Attivita Integrata di Neuroscienze, Parma (Italy)

    2007-10-15

    Diffusion-weighted imaging (DWI), perfusion-weighted imaging (PWI) and MR spectroscopy (MRS) provide useful data for tumor evaluation. To assess the contribution of these multimodal techniques in grading glial neoplasms, we compared the value of DWI, PWI and MRS in the evaluation of histologically proven high- and low-grade gliomas in a population of 105 patients. Independently for each modality, the following variables were used to compare the tumors: minimum apparent diffusion coefficient (ADC) and maximum relative cerebral blood volume (rCBV) normalized values between tumor and healthy tissue, maximum Cho/Cr ratio and minimum NAA/Cr ratio in tumor, and scored lactate and lipid values in tumor. The Mann-Whitney and Wilcoxon tests were employed to compare DWI, PWI and MRS between tumor types. Logistic regression analysis was used to determine which parameters best increased the diagnostic accuracy in terms of sensitivity, specificity, and positive and negative predictive values. ROC curves were determined for parameters with high sensitivity and specificity to identify threshold values to separate high- from low-grade lesions. Statistically significant differences were found for rCBV tumor/normal tissue ratio, and NAA/Cr ratio in tumor and Cho/Cr ratio in tumor between low- and high-grade tumors. The best performing single parameter for group classification was the normalized rCBV value; including all parameters, statistical significance was reached by rCBV tumor/normal tissue ratio, NAA/Cr tumor ratio and lactate. From the ROC curves, a high probability for a neoplasm to be a high-grade lesion was associated with a rCBV tumor/normal tissue ratio of >1.16 and NAA/Cr tumor ratio of <0.44. Combining PWI and MRS with conventional MR imaging increases the accuracy of the attribution of malignancy to glial neoplasms. The best performing parameter was found to be the perfusion level. (orig.)

  17. Granular gases under extreme driving

    Science.gov (United States)

    Kang, W.; Machta, J.; Ben-Naim, E.

    2010-08-01

    We study inelastic gases in two dimensions using event-driven molecular-dynamics simulations. Our focus is the nature of the stationary state attained by rare injection of large amounts of energy to balance the dissipation due to collisions. We find that under such extreme driving, with the injection rate much smaller than the collision rate, the velocity distribution has a power-law high-energy tail. The numerically measured exponent characterizing this tail is in excellent agreement with predictions of kinetic theory over a wide range of system parameters. We conclude that driving by rare but powerful energy injection leads to a well-mixed gas and constitutes an alternative mechanism for agitating granular matter. In this distinct nonequilibrium steady state, energy cascades from large to small scales. Our simulations also show that when the injection rate is comparable with the collision rate, the velocity distribution has a stretched exponential tail.

  18. Images

    Data.gov (United States)

    National Aeronautics and Space Administration — Images for the website main pages and all configurations. The upload and access points for the other images are: Website Template RSW images BSCW Images HIRENASD...

  19. The use of high-field intra-operative magnetic resonance imaging combined with language functional neuronavigation in glioma surgery

    Directory of Open Access Journals (Sweden)

    Yan ZHAO

    2011-07-01

    Full Text Available Objective To explore the effect of high-field intra-operative magnetic resonance imaging(iMRI combined with language functional neuronavigation in resection of glioma in language area of dominant hemisphere of the brain.Methods Twenty right handed patients(12 males and 8 females,aged from 20 to 61 years with mean of 43.6 years with glioma close to arcuate fasciculus were involved in present study,and they were stratified into normal group(n=9 and aphasia group(n=11 according to the preoperative aphasia quotient(AQ.All the patients underwent surgical operation assisted by arcuate fasciculus navigator,and the high-field iMRI was performed with a 1.5-T magnetic resonance scanner.The 3D reconstructed arcuate fasciculus images were integrated into neuronavigation system before the operation,and used by combining with functional neuronavigation under microscope during the surgical procedure.Pre-operatirely,and 2-4 weeks,3-6 months postoperative,the patients were examined with magnetic resonance scanning and aphasia quotients examination.Results Pre-operative and intra-operative arcuate fasciculus reconstruction was completed in all the 20 patients,and neuronavigation under microscope were performed after the 3D images integrated into neuronavigation system.Patients of normal AQ(94.5±5.5 retained the normal level,except one patients who developed new conduction aphasia syndrome(AQ=81.8 2-4 weeks after operation.The AQ of aphasia group(89.4±5.8 was significantly improved than that before operation(84.9±8.7,P < 0.05,except 2 patients whose language deficit was exacerbated due to tumor recurrence.The AQ of normal group(98.3±0.5 remained at normal level,while that of aphasia group(95.2±2.6 was significantly improved 3-6 months after operation compared with that at 2-4 weeks after operation(P < 0.05.There were no other new neurologic deficits and death in both groups.Conclusion High-field iMRI combined with functional neuronavigation is a safe and

  20. Unconventional gases: a North-American energy revolution not without consequences for Europe

    International Nuclear Information System (INIS)

    2011-01-01

    This paper gives a definition of the different existing unconventional gases (coal-bed methane, tight gases, shale gases), and outlines that, although these gases as well as the techniques to extract them have been well known for a long time, it is the combination of two of these techniques (hydraulic fracturing or fracking, and horizontal drilling) which enables the current technological development and the exploitation of these gases. It also outlines that the current situation in terms of natural resources favours such a development. It evokes projects in the United States, China, India, Europe, and more particularly in France, stressing that environmental issues and population density in Europe are obstacles to perform these drillings. The author questions the production cost issue and explains how these developments, notably in the USA, may change completely the world energetic landscape, and therefore entail a review of the European energy agenda. He explores the possible consequences of a durable decrease of gas prices

  1. Erosion of volatile elemental condensed gases by keV electron and light-ion bombardment

    International Nuclear Information System (INIS)

    Schou, J.

    1991-11-01

    Erosion of the most volatile elemental gases by keV electron and light-ion bombardment has been studied at the experimental setup at Risoe. The present work includes frozen neon, argon, krypton, nitrogen, oxygen and three hydrogen isotopes, deuterium, hydrogen deuteride and hydrogen. The yield of these condensed gases has been measured as a function of film thickness and primary energy for almost all combinations of primary particles (1-3 keV electrons, 5-10 keV hydrogen- and helium ions) and ices. These and other existing results show that there are substantial common features for the sputtering of frozen elemental gases. Within the two groups, the solid rare gases and the solid molecular gases, the similarity is striking. The hydrogenic solids deviate in some respects from the other elements. The processes that liberate kinetic energy for the particle ejection in sputtering are characteristic of the specific gas. (au) 3 tabs., 12 ills., 159 refs

  2. Usefulness of combination post-stress dysfunction and perfusion imaging in technetium-99m-tetrofosmin myocardial scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Yamazaki, Yoko; Imai, Kamon; Konaka, Ryohei; Nakajima, Takatomo; Goto, Sayaka; Horie, Toshinobu [Saitama Cardiovascular and Respiratory Center, Konan (Japan); Saito, Satoshi; Ozawa, Yukio; Kanmatsuse, Katsuo

    2001-09-01

    Myocardial perfusion imaging has lower sensitivity for the diagnosis of coronary artery disease in patients with three-vessel disease. The presence of post-stress dysfunction of the left ventricle, evaluated by electrocardiography (ECG) gated single photon emission computed tomography (SPECT) with a quantitative gated SPECT program, was investigated in patients with coronary artery disease, and also whether combining post-stress dysfunction and myocardial perfusion imaging improved the diagnosis of coronary artery disease. ECG gated technetium-99m-tetrofosmin SPECT was performed using a one day, stress and rest, protocol in 139 patients. SPECT and coronary angiography were performed within 1 month. The coronary artery disease group consisted of 89 patients: 43 with one-vessel disease (1VD), 28 with two-vessel disease (2VD), and 18 with three-vessel disease (3VD). The group with zero-vessel disease (0VD) consisted of 50 patients. According to post-stress and rest ejection fraction (EF) and end-systolic volume (ESV), post-stress dysfunction is defined as follows: rest EF - post-stress EF{>=}5% and post-stress ESV - rest ESV{>=}5ml. In the coronary artery disease group, post-stress ESV was larger than rest ESV (37.8{+-}26.4, 34.0{+-}24.2 ml, p<0.001), and post-stress EF was lower than rest EF (61.5{+-}11.1%, 64.2{+-}10.8%, p<0.001). In the 0VD group, ESV and EF were the same for post-stress and rest (25.7{+-}20.8, 26.2{+-}21.6 ml, NS; 70.4{+-}9.5%, 70.0{+-}9.6%, NS). Post-stress dysfunction was 6.0% in the 0VD group and 30.3% in the coronary artery disease group (p<0.001). Furthermore, post-stress dysfunction in the 2VD (35.7%) and 3VD (38.9%) groups was higher than that in the 0VD group (p<0.01, p<0.01). Sensitivity of coronary artery disease diagnosis by myocardial perfusion imaging was 75%. The combination of post-stress dysfunction and myocardial perfusion imaging improved sensitivity from 75% to 82% (p<0.05), but reduced the specificity from 92% to 86% (p=0

  3. Combining Infrasound and Imaging Techniques to Characterize and Quantify Eruptive Activity at Karymsky Volcano, Kamchatka, Russia

    Science.gov (United States)

    Fee, D.; Lopez, T. M.; Rowell, C.; Matoza, R. S.; Szuberla, C.; Prata, F.; Firstov, P.; Makhmudov, E.

    2012-12-01

    Changes in atmospheric pressure at volcanic vents caused by the rapid release and expansion of volcanic material (e.g., gas, ash, lava) produce low frequency sound waves known as infrasound. Because of the direct link between the infrasound source and the eruption and emission of volcanic material, complementary direct and remote observations of gas, ash, and other eruptive phenomena can be combined with infrasound measurements to characterize and quantify volcanic activity. Here we present coincident measurements collected over two 10-day periods at Karymsky Volcano in August 2011 and July 2012 of infrasound, SO2, thermal radiation, ash (2011 only), and visual imagery. Infrasound and audible (up to 250 Hz) acoustic data were recorded using arrays of portable digital microphones. SO2 emissions were measured using both a scanning FLYSPEC ultraviolet spectrometer system as well as a CyClops infrared camera equipped with broadband, 8.6, 10, and 11 micron filters permitting detection and quantification of both SO2 and ash. A FLIR infrared camera was utilized to record high temporal resolution thermal observations of the volcanic emissions and hot eruption deposits. Lastly, visual imagery was taken with an HD camcorder. Correlations between this multiparameter dataset allow a better understanding of both the infrasound data and eruptive activity. Karymsky Volcano is one of the most active and dynamic volcanoes in Kamchatka, Russia, with activity during our experiments consisting of vigorous degassing, frequent ash explosions, apparent vent sealing, and intermittent explosive magmatic eruptions. This varied activity produced diverse acoustic and emissions signals. Large explosive eruptions in 2011 are preceded by vent sealing and produce high-amplitude infrasound with occasional visible shock waves. Vigorous gas jetting is also observed and accompanied by elevated SO2 emissions and low infrasound levels. The gas jetting produced clear audible sound (~20-100 Hz) that

  4. Combined Use of a Crop Model and FORMOSAT-2 Images for Permanent Grassland and Water Monitoring in Mediterranean Region

    Science.gov (United States)

    Hadria, Rachid; Courault, Dominique; Ruget, Francois; Olioso, Albert; Duchemin, Benoit; Desfonds, Veronique; Bertrand, Nadine; Hagolle, Olivier; Dedieu, Gerard

    2009-11-01

    The objective of this study is to provide tools to improve crop and water management in Mediterranean regions. The specific aim is twofold: 1) study the feasibility of using optical remote sensing data acquired at high spatio-temporal resolutions for crop agricultural practice monitoring and, 2) test the capacity of crop modelling to estimated water balance and crop production.We developed a methodology based on the combined use of FORMOSAT-2 images and STICS crop model to estimate evapotranspiration and drainage of irrigated grasslands in 'the Crau' region in the South Eastern France. Simple algorithms were developed to retrieve the dynamic of Leaf Area Index (LAI) for each plot of the studied region and the main agricultural practices such as mowing and irrigation dates. This information was then used to parameterize STICS, applied at region scale to estimate the spatial variability of water budget associated with the biomass productions. Satisfactory results were obtained when compared to ground measurements.s

  5. Deep feature extraction and combination for remote sensing image classification based on pre-trained CNN models

    Science.gov (United States)

    Chaib, Souleyman; Yao, Hongxun; Gu, Yanfeng; Amrani, Moussa

    2017-07-01

    Understanding a scene provided by Very High Resolution (VHR) satellite imagery has become a more and more challenging problem. In this paper, we propose a new method for scene classification based on different pre-trained Deep Features Learning Models (DFLMs). DFLMs are applied simultaneously to extract deep features from the VHR image scene, and then different basic operators are applied for features combination extracted with different pre-trained Convolutional Neural Networks (CNN) models. We conduct experiments on the public UC Merced benchmark dataset, which contains 21 different areal categories with sub-meter resolution. Experimental results demonstrate the effectiveness of the proposed method, as compared to several state-of-the-art methods.

  6. Imaging of the magnetic field structure in megagauss plasmas by combining pulsed polarimetry with an optical Kerr effect shutter technique

    International Nuclear Information System (INIS)

    Smith, R. J.

    2010-01-01

    Pulsed polarimetry in combination with a high speed photographic technique based on the optical Kerr effect is described. The backscatter in a pulsed polarimeter is directed through a scattering cell and photographed using an ∼1 ps shutter, essentially freezing the intensity pattern. The image provides both the local electron density and magnetic field distributions along and transverse to the laser sightline. Submillimeter spatial resolution is possible for probing wavelengths in the visible due to the high densities and strong optical activity. Pulsed polarimetry is thereby extended to centimeter-sized plasmas with n e >10 19 -10 20 cm -3 and B>20-100 T (MG) produced by multiterawatt, multimega-ampere electrical drivers, wire Z pinches, and liner imploded magnetized plasmas.

  7. CuS-Based Theranostic Micelles for NIR-Controlled Combination Chemotherapy and Photothermal Therapy and Photoacoustic Imaging.

    Science.gov (United States)

    Chen, Guojun; Ma, Ben; Wang, Yuyuan; Xie, Ruosen; Li, Chun; Dou, Kefeng; Gong, Shaoqin

    2017-12-06

    Cancer remains a major threat to human health due to low therapeutic efficacies of currently available cancer treatment options. Nanotheranostics, capable of simultaneous therapy and diagnosis/monitoring of diseases, has attracted increasing amounts of attention, particularly for cancer treatment. In this study, CuS-based theranostic micelles capable of simultaneous combination chemotherapy and photothermal therapy (PTT), as well as photoacoustic imaging, were developed for targeted cancer therapy. The micelle was formed by a CuS nanoparticle (NP) functionalized by thermosensitive amphiphilic poly(acrylamide-acrylonitrile)-poly(ethylene glycol) block copolymers. CuS NPs under near-infrared (NIR) irradiation induced a significant temperature elevation, thereby enabling NIR-triggered PTT. Moreover, the hydrophobic core formed by poly(acrylamide-acrylonitrile) segments used for drug encapsulation exhibited an upper critical solution temperature (UCST; ∼38 °C), which underwent a hydrophobic-to-hydrophilic transition once the temperature rose above the UCST induced by NIR-irradiated CuS NPs, thereby triggering a rapid drug release and enabling NIR-controlled chemotherapy. The CuS-based micelles conjugated with GE11 peptides were tested in an epidermal growth factor receptor-overexpressing triple-negative breast cancer model. In both two-dimensional monolayer cell and three-dimensional multicellular tumor spheroid models, GE11-tagged CuS-based micelles under NIR irradiation, enabling the combination chemotherapy and PTT, exhibited the best therapeutic outcome due to a synergistic effect. These CuS-based micelles also displayed a good photoacoustic imaging ability under NIR illumination. Taken together, this multifunctional CuS-based micelle could be a promising nanoplatform for targeted cancer nanotheranostics.

  8. In the assessment of supratentorial glioma grade: The combined role of multivoxel proton MR spectroscopy and diffusion tensor imaging

    International Nuclear Information System (INIS)

    Zou, Q.-G.; Xu, H.-B.; Liu, F.; Guo, W.; Kong, X.-C.; Wu, Y.

    2011-01-01

    Aim: To detect a difference in the parameters derived from proton magnetic resonance spectroscopy ( 1 H-MRS) and diffusion tensor imaging (DTI) between low-grade and high-grade gliomas, and to evaluate whether the combination of these two techniques can improve the diagnostic accuracy of conventional magnetic resonance imaging (MRI) in supratentorial glioma grading. Materials and methods: Thirty patients with histologically proved supratentorial brain gliomas (12 low grade, 18 high grade) were prospectively evaluated with contrast material-enhanced MRI, DTI, and multivoxel 1 H-MRS (135 ms echo time). The tumour grades determined using the three methods were then compared with those obtained at histopathology. Receiver operating characteristic (ROC) analyses were performed to determine the optimum thresholds for glioma grading. Independent sample t-test, Spearman's rank correlation, and the Fisher's exact test were also carried out for statistical analysis. p -6 mm 2 /s for the calculated ADC value, corresponding to the maximum Youden index from the ROC curve of the above-selected parameters, the resultant sensitivities, specificities, positive predictive values (PPVs), negative predictive values (NPVs), and Kappa values were all higher and the fraction of misclassified tumour was lower when compared with conventional MRI. However, only NAA/Cho and ADC calculation contributed to the significant difference (p < 0.01) in the assessment of glioma grade compared to conventional MRI alone, and the grading results of statistical tests comparing those two parameters were highly consistent (kappa value = 0.798). Conclusion: Thresholds for NAA/Cho and calculated ADC values, corresponding to maximum Youden index from ROC curve analyses, helped to improve the accuracy of supratentorial glioma grading when compared with conventional MRI alone. In addition, a combination of NAA/Cho and ADC calculation were more useful together than each alone in a clinical setting to evaluate

  9. Effect of optical property estimation accuracy on tomographic bioluminescence imaging: simulation of a combined optical-PET (OPET) system

    Energy Technology Data Exchange (ETDEWEB)

    Alexandrakis, George [Crump Institute for Molecular Imaging, David Geffen School of Medicine at UCLA, University of California, 700 Westwood Plaza, Los Angeles, CA 90095 (United States); Rannou, Fernando R [Departamento de Ingenieria Informatica, Universidad de Santiago de Chile (USACH), Av. Ecuador 3659, Santiago (Chile); Chatziioannou, Arion F [Crump Institute for Molecular Imaging, David Geffen School of Medicine at UCLA, University of California, 700 Westwood Plaza, Los Angeles, CA 90095 (United States)

    2006-04-21

    Inevitable discrepancies between the mouse tissue optical properties assumed by an experimenter and the actual physiological values may affect the tomographic localization of bioluminescent sources. In a previous work, the simplifying assumption of optically homogeneous tissues led to inaccurate localization of deep sources. Improved results may be obtained if a mouse anatomical map is provided by a high-resolution imaging modality and optical properties are assigned to segmented tissues. In this work, the feasibility of this approach was explored by simulating the effect of different magnitude optical property errors on the image formation process of a combined optical-PET system. Some comparisons were made with corresponding simulations using higher spatial resolution data that are typically attainable by CCD cameras. In addition, simulation results provided insights on some of the experimental conditions that could lead to poor localization of bioluminescent sources. They also provided a rough guide on how accurately tissue optical properties need to be known in order to achieve correct localization of point sources with increasing tissue depth under low background noise conditions.

  10. Greenhouse Gases Concentrations in the Atmosphere Along ...

    African Journals Online (AJOL)

    This study investigated effect of vehicular emission on greenhouse gases concentrations along selected roads of different traffic densities in Abeokuta, Ogun State, Nigeria. Nine roads comprised highway, commercial and residential were selected. Greenhouse Gases (GHGs) were determined from both sides of the roads by ...

  11. 40 CFR 89.312 - Analytical gases.

    Science.gov (United States)

    2010-07-01

    ... gases must be available for operation: (1) Purified nitrogen (Contamination ≤ 1 ppm C, ≤ 1 ppm CO, ≤ 400... span gases. (1) Calibration gas values are to be derived from NIST Standard Reference Materials (SRM's... purified synthetic air ; (ii) C3H8 and purified nitrogen (optional for raw measurements); (iii) CO and...

  12. Combination of Synthetic Chemistry and Live-Cell Imaging Identified a Rapid Cell Division Inhibitor in Tobacco and Arabidopsis thaliana.

    Science.gov (United States)

    Nambo, Masakazu; Kurihara, Daisuke; Yamada, Tomomi; Nishiwaki-Ohkawa, Taeko; Kadofusa, Naoya; Kimata, Yusuke; Kuwata, Keiko; Umeda, Masaaki; Ueda, Minako

    2016-11-01

    Cell proliferation is crucial to the growth of multicellular organisms, and thus the proper control of cell division is important to prevent developmental arrest or overgrowth. Nevertheless, tools for controlling cell proliferation are still poor in plant. To develop novel tools, we focused on a specific compound family, triarylmethanes, whose members show various antiproliferative activities in animals. By combining organic chemistry to create novel and diverse compounds containing the triarylmethyl moiety and biological screens based on live-cell imaging of a fluorescently labeled tobacco Bright Yellow-2 (BY-2) culture cell line (Nicotiana tabacum), we isolated (3-furyl)diphenylmethane as a strong but partially reversible inhibitor of plant cell division. We also found that this agent had efficient antiproliferative activity in developing organs of Arabidopsis thaliana without causing secondary defects in cell morphology, and induced rapid cell division arrest independent of the cell cycle stage. Given that (3-furyl)diphenylmethane did not affect the growth of a human cell line (HeLa) and a budding yeast (Saccharomyces cerevisiae), it should act specifically on plants. Taking our results together, we propose that the combination of desired chemical synthesis and detailed biological analysis is an effective tool to create novel drugs, and that (3-furyl)diphenylmethane is a specific antiproliferative agent for plants. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  13. The combined use of conventional MRI and MR spectroscopic imaging increases the diagnostic accuracy in amyotrophic lateral sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Cervo, Amedeo [Department of Advanced Biomedical Sciences, University “Federico II”, Naples (Italy); Cocozza, Sirio, E-mail: siriococozza@hotmail.it [Department of Advanced Biomedical Sciences, University “Federico II”, Naples (Italy); Saccà, Francesco [Department of Neurosciences, Reproductive Sciences and Odontostomatology, University “Federico II”, Naples (Italy); Giorgio, Sara M.d.A. [Department of Advanced Biomedical Sciences, University “Federico II”, Naples (Italy); Morra, Vincenzo Brescia [Department of Neurosciences, Reproductive Sciences and Odontostomatology, University “Federico II”, Naples (Italy); Tedeschi, Enrico [Department of Advanced Biomedical Sciences, University “Federico II”, Naples (Italy); Marsili, Angela; Vacca, Giovanni [Department of Neurosciences, Reproductive Sciences and Odontostomatology, University “Federico II”, Naples (Italy); Palma, Vincenzo [U.O.C. Neurofisiopatologia, PO S. Gennaro ASL Napoli 1, Naples (Italy); Brunetti, Arturo [Department of Advanced Biomedical Sciences, University “Federico II”, Naples (Italy); Quarantelli, Mario [Biostructure and Bioimaging Institute, National Research Council, Naples (Italy)

    2015-01-15

    Highlights: • We assessed in ALS the diagnostic accuracy of MRI signal and MRS data used alone and in combination. • We found that T2-hypointensity and NAA decrease in motor cortex are two independent phenomena. • These two variables taken alone do not provide acceptable diagnostic accuracy in ALS. • The same variables, when used in combination, improve the diagnostic accuracy of MRI in ALS. - Abstract: Purpose: We aimed to assess, in amyotrophic lateral sclerosis (ALS), the diagnostic accuracy of the combined use of conventional MRI signal changes (namely, hypointensity of the precentral cortex and hyperintensity of the corticospinal tracts on T2-weighted images), and N-Acetyl-Aspartate (NAA) reduction in the motor cortex at Magnetic Resonance Spectroscopy (MRS), which are affected by limited diagnostic accuracy when used separately. Methods: T2-hypointensity and NAA/(Choline + Creatine) ratio of the precentral gyrus and T2-hyperintensity of the corticospinal tracts were measured in 84 ALS patients and 28 healthy controls, using a Region-of-Interest approach. Sensitivity and specificity values were calculated using Fisher stepwise discriminant analysis, and cross-validated using the leave-one-out method. Results: Precentral gyrus T2 signal intensity (p < 10{sup −4}) and NAA peak (p < 10{sup −6}) were significantly reduced in patients, and their values did not correlate significantly to each other both in patients and controls, while no significant differences were obtained in terms of T2-hyperintensity of the corticospinal tract. Sensitivity and specificity of the two discriminant variables, taken alone, were 71.4% and 75.0%, for NAA peak, and 63.1% and 71.4% for T2-hypointensity, respectively. When using these two variables in combination, a significant increase in sensitivity (78.6%) and specificity (82.1%) was achieved. Conclusions: Precentral gyrus T2-hypointensity and NAA peak are not significantly correlated in ALS patients, suggesting that they

  14. Combination of chemical suppression techniques for dual suppression of fat and silicone at diffusion-weighted MR imaging in women with breast implants

    International Nuclear Information System (INIS)

    Koh, Dow-Mu; Hughes, J.; Blackledge, M.; Leach, M.O.; Collins, D.J.; Burns, S.; Stemmer, A.; Kiefer, B.

    2012-01-01

    Silicone breast prostheses prove technically challenging when performing diffusion-weighted MR imaging in the breasts. We describe a combined fat and chemical suppression scheme to achieve dual suppression of fat and silicone, thereby improving the quality of diffusion-weighted images in women with breast implants. MR imaging was performed at 3.0 and 1.5 T in women with silicone breast implants using short-tau inversion recovery (STIR) fat-suppressed echo-planar (EPI) diffusion-weighted MR imaging (DWI) on its own and combined with the slice-select gradient-reversal (SSGR) technique. Imaging was performed using dedicated breast imaging coils. Complete suppression of the fat and silicone signal was possible at 3.0 T using EPI DWI with STIR and SSGR, evaluated with dedicated breast coils. However, a residual silicone signal was still perceptible at 1.5 T using this combined approach. Nevertheless, a further reduction in silicone signal at 1.5 T could be achieved by employing thinner slice partitions and the addition of the chemical-selective fat-suppression (CHESS) technique. DWI using combined STIR and SSGR chemical suppression techniques is feasible to eliminate or reduce silicone signal from prosthetic breast implants. (orig.)

  15. Kinetic Theory of Granular Gases

    International Nuclear Information System (INIS)

    Trizac, Emmanuel

    2005-01-01

    Granular gases are composed of macroscopic bodies kept in motion by an external energy source such as a violent shaking. The behaviour of such systems is quantitatively different from that of ordinary molecular gases: due to the size of the constituents, external fields have a stronger effect on the dynamics and, more importantly, the kinetic energy of the gas is no longer a conserved quantity. The key role of the inelasticity of collisions has been correctly appreciated for about fifteen years, and the ensuing consequences in terms of phase behaviour or transport properties studied in an increasing and now vast body of literature. The purpose of this book is to help the newcomer to the field in acquiring the essential theoretical tools together with some numerical techniques. As emphasized by the authors-who were among the pioneers in the domain- the content could be covered in a one semester course for advanced undergraduates, or it could be incorporated in a more general course dealing with the statistical mechanics of dissipative systems. The book is self-contained, clear, and avoids mathematical complications. In order to elucidate the main physical ideas, heuristic points of views are sometimes preferred to a more rigorous route that would lead to a longer discussion. The 28 chapters are short; they offer exercises and worked examples, solved at the end of the book. Each part is supplemented with a relevant foreword and a useful summary including take-home messages. The editorial work is of good quality, with very few typographical errors. In spite of the title, kinetic theory stricto sensu is not the crux of the matter covered. The authors discuss the consequences of the molecular chaos assumption both at the individual particle level and in terms of collective behaviour. The first part of the book addresses the mechanics of grain collisions. It is emphasized that considering the coefficient of restitution ε -a central quantity governing the inelasticity of

  16. Greenhouse gases and emissions trading

    International Nuclear Information System (INIS)

    LeBlanc, A.; Dudek, D.J.

    1993-01-01

    Global cooperation is essential in cutting greenhouse-gas emissions, say Alice LeBlanc and Daniel J. Dudek of the Environmental Defense in New York City. The first step, they continue, is agreement among nations on an overall global limit for all greenhouse gases, followed by an allocation of the global limit among nations. The agreements must contain effective reporting and monitoring systems and enforcement provisions, they add. The Framework Convention on Climate Change, signed by most nations of the world in Brazil in 1992, provides the foundation for such an agreement, LeBlanc and Dudek note. open-quotes International emissions trading is a way to lower costs and expand reduction options for the benefit of all,close quotes they contend. Under such an arrangement, an international agency would assign allowances, stated in tons of carbon dioxide. Countries would be free to buy and sell allowances, but no country could exceed, in a given year, the total allowances it holds. By emitting less than its allowed amount, a country would accumulate more allowances, which it could sell. The authors claim such a system would offer benefits to the world economy by saving billions of dollars in pollution-reduction costs while still achieving emission limits established in an international agreement

  17. Improving the Grading Accuracy of Astrocytic Neoplasms Noninvasively by Combining Timing Information with Cerebral Blood Flow: A Multi-TI Arterial Spin-Labeling MR Imaging Study.

    Science.gov (United States)

    Yang, S; Zhao, B; Wang, G; Xiang, J; Xu, S; Liu, Y; Zhao, P; Pfeuffer, J; Qian, T

    2016-12-01

    Systematic and accurate glioma grading has clinical significance. We present the utility of multi-TI arterial spin-labeling imaging and provide the bolus arrival time maps for grading astrocytomas. Forty-three patients with astrocytomas (21 men; mean age, 51 years) were recruited. The classification abilities of conventional MR imaging features, normalized CBF value derived from multi-TI arterial spin-labeling imaging, normalized bolus arrival time, and normalized CBF derived from single-TI arterial spin-labeling were compared in patients with World Health Organization (WHO) grade II, III, and IV astrocytomas. The normalized CBF value derived from multi-TI arterial spin-labeling imaging was higher in patients with higher grade astrocytoma malignancies compared with patients with lower grade astrocytomas, while the normalized bolus arrival time showed the opposite tendency. The normalized CBF value derived from the multi-TI arterial spin-labeling imaging showed excellent performance with areas under the receiver operating characteristic curve of 0.813 (WHO II versus III), 0.964 (WHO II versus IV), 0.872 (WHO III versus IV), and 0.883 (low-grade-versus-high-grade gliomas). The normalized CBF value derived from single-TI arterial spin-labeling imaging could statistically differentiate the WHO II and IV groups (area under the receiver operating characteristic curve = 0.826). The normalized bolus arrival time effectively identified the WHO grades II and III with an area under the receiver operating characteristic curve of 0.836. Combining the normalized CBF value derived from multi-TI arterial spin-labeling imaging and normalized bolus arrival time improved the diagnostic accuracy from 65.10% to 72.10% compared with the normalized CBF value derived from multi-TI arterial spin-labeling imaging being applied independently. The combination of multi-TI arterial spin-labeling imaging and conventional MR imaging had the best performance, with a diagnostic accuracy of 81

  18. Beneficial Effects of Environmental Gases: Health Prospective

    International Nuclear Information System (INIS)

    Hussein, A.Z.; IBrahim, M.S.; Zakaria, Kh.M.

    2009-01-01

    Radioactive radon gas is widely considered to be a health hazard by environmental agencies in the United States and in Europe. Yet despite the warnings of these agencies, thousands of people annually expose themselves to radon for therapeutic purposes, in facilities ranging from rustic old mines, to upscale spas and clinics. The inert natural radioactive gas radon has been used since the beginning of the century in the treatment of rheumatic diseases. In many places in the world, radon is used for therapeutic purposes for various diseases. Radon inhalation is applied in a thermal gallery with atmospheric radon concentrations up to 100 kBq/m3, elevated temperature up to 41 EC , and humidity close to 100%, or in the form of radon baths where Rn is emanated from water with high natural Rn activity. Frequently, a combination of both treatment procedures is applied. Evidence from empirical experience and from clinical observational studies suggests that radon has analgesic, anti inflammatory and immune-stimulating effects. Ozone is one of nature's most powerful oxidants. It increases the effectiveness of the antioxidant enzyme system, which scavenge excess free radicals in the body. It is used in water purification and sewage treatment and is now being applied medically to treat many diseases from wounds and colitis to cancer, stroke and AIDS. According to the dosage and concentration range, medical ozone is a pharmaceutical agent that exerts specific properties and a well-defined range of efficacy. This paper describes the medical application of environmental gases: radon and ozone

  19. Development of a personal multi-pollutant exposure sampler for particulate matter and criteria gases

    Energy Technology Data Exchange (ETDEWEB)

    Chang, I.T.; Sarnat, J.; Wolfson, J.M.; Rojas-Bracho, L.; Suh, H.H.; Koutrakis, P. [Harvard Univ., Boston, MA (United States). School of Public Health

    1999-12-01

    A novel personal sampler is reported which allows simultaneous measurement of PM{sub 2,5}, and PM{sub 10}, ozone, nitrogen dioxide, and sulfur dioxide. This method combines previously used samplers for personal mass measurement with passive samplers for criteria gases and uses a single pump. Preliminarily results are reported for laboratory chamber tests and field comparisons with reference methods for both mass and criteria gases. These results demonstrate the suitability of this sampler of exposure assessment studies. (authors)

  20. Incremental Diagnostic Performance of Combined Parameters in the Detection of Severe Coronary Artery Disease Using Exercise Gated Myocardial Perfusion Imaging.

    Directory of Open Access Journals (Sweden)

    Chia-Ju Liu

    Full Text Available Myocardial perfusion imaging (MPI using gated single-photon emission tomography (gSPECT may underestimate the severity of coronary artery disease (CAD. This study aimed to evaluate the significance of combined parameters derived from gSPECT, as well as treadmill stress test parameters, in the detection of severe CAD.A total of 211 consecutive patients referred for exercise MPI between June 2011 and June 2013 (who received invasive coronary angiography within six months after MPI were retrospectively reviewed. Exercise MPI was performed with Bruce protocol and 201Tl injected at peak exercise. Gated SPECT was performed using a cadmium-zinc-telluride camera and processed by QPS/QGS software. Perfusion defect abnormalities such as sum stress score (SSS; sum difference score, algorithm-derived total perfusion deficits, transient ischemic dilatation ratios of end-diastolic volumes and end-systolic volumes, post-stress changes in ejection fraction, and lung/heart ratio (LHR were calculated. Treadmill parameters, including ST depression (STD at the 1st and 3rd minutes of recovery stage (1'STD and 3'STD, maximal STD corrected by heart rate increment (ST/HR, heart rate decline in 1st and 3rd minutes of recovery stage, recovery heart rate ratio (HR ratio, systolic and mean blood pressure ratios (SBP ratio and MAP ratio during recovery phase were recorded. Diagnostic performances of these parameters were analyzed with receiver operating characteristic (ROC analysis and logistic regression for detection of left main (≥ 50% or 3-vessel disease (all ≥ 70% luminal stenosis on invasive angiography.Among various MPI and treadmill parameters used for detection of severe CAD, SSS and ST/HR had the highest AUC (0.78, 0.73, p = NS and best cut-off values (SSS > 6, ST/HR > 17.39 10-2mV/bpm, respectively. By univariate logistic regression, all parameters except 1'HRR, 3'HRR, SBP and MAP ratios increased the odds ratio of severe CAD. Only increased L/H ratio, 3'STD

  1. Photoelectron spectrometer for attosecond spectroscopy of liquids and gases.

    Science.gov (United States)

    Jordan, I; Huppert, M; Brown, M A; van Bokhoven, J A; Wörner, H J

    2015-12-01

    A new apparatus for attosecond time-resolved photoelectron spectroscopy of liquids and gases is described. It combines a liquid microjet source with a magnetic-bottle photoelectron spectrometer and an actively stabilized attosecond beamline. The photoelectron spectrometer permits venting and pumping of the interaction chamber without affecting the low pressure in the flight tube. This pressure separation has been realized through a sliding skimmer plate, which effectively seals the flight tube in its closed position and functions as a differential pumping stage in its open position. A high-harmonic photon spectrometer, attached to the photoelectron spectrometer, exit port is used to acquire photon spectra for calibration purposes. Attosecond pulse trains have been used to record photoelectron spectra of noble gases, water in the gas and liquid states as well as solvated species. RABBIT scans demonstrate the attosecond resolution of this setup.

  2. Autoradiographic imaging of cerebral ischaemia using a combination of blood flow and hypoxic markers in an animal model

    International Nuclear Information System (INIS)

    Lythgoe, M.F.; Williams, S.R.; Wiebe, L.I.; McEwan, A.J.B.; Gordon, I.

    1997-01-01

    Current routine clinical techniques, including angiography and perfusional single-photon emission tomography, can be used to indicate problems in cerebral vascular supply and areas of cerebral hypoperfusion following a stroke, but cannot distinguish between ischaemic core and penumbra. In order to image specifically the penumbra, a method or indicator should be able to define areas with reduced blood flow, and a degree of metabolic compromise. In this context, the tissue could be regarded as hypoxic rather than ischaemic, and we have therefore chosen to investigate the potential of radio-labelled hypoxic markers in the study of ischaemia. In order to combine a hypoxic marker with a blood flow marker we used technetium-99m hexamethylpropylene amine oxime ( 99m Tc-HMPAO) and iodine-125 iodoazomycin arabinoside ( 125 I-IAZA), during cerebral ischaemia in the rat middle cerebral artery occlusion model. 99m Tc-HMPAO and 125 I-IAZA were injected simultaneously 2 h following occlusion of the middle cerebral artery, and 5 h before decapitation. Paired autoradiograms were produced and compared. Three distinct patterns emerged from the autoradiograms: slightly decreased perfusion with no uptake of the hypoxic marker indicating an area of misery perfusion; moderately decreased perfusion with concomitant uptake of iodoazomycin arabinoside, a region of hypoxia; and severely decreased perfusion with no retention of the hypoxic tracer. In conclusion, we present a new use for an imaging agent in the investigation of cerebral hypoxia. This agent, IAZA together with HMPAO, provides a means of separating the penumbra into regions of misery perfusion and hypoxia. The potential impact of this may be important in the clinical investigation of stroke. (orig.). With 3 figs

  3. Design Studies of a CZT-based Detector Combined with a Pixel-Geometry-Matching Collimator for SPECT Imaging.

    Science.gov (United States)

    Weng, Fenghua; Bagchi, Srijeeta; Huang, Qiu; Seo, Youngho

    2013-10-01

    Single Photon Emission Computed Tomography (SPECT) suffers limited efficiency due to the need for collimators. Collimator properties largely decide the data statistics and image quality. Various materials and configurations of collimators have been investigated in many years. The main thrust of our study is to evaluate the design of pixel-geometry-matching collimators to investigate their potential performances using Geant4 Monte Carlo simulations. Here, a pixel-geometry-matching collimator is defined as a collimator which is divided into the same number of pixels as the detector's and the center of each pixel in the collimator is a one-to-one correspondence to that in the detector. The detector is made of Cadmium Zinc Telluride (CZT), which is one of the most promising materials for applications to detect hard X-rays and γ -rays due to its ability to obtain good energy resolution and high light output at room temperature. For our current project, we have designed a large-area, CZT-based gamma camera (20.192 cm×20.192 cm) with a small pixel pitch (1.60 mm). The detector is pixelated and hence the intrinsic resolution can be as small as the size of the pixel. Materials of collimator, collimator hole geometry, detection efficiency, and spatial resolution of the CZT detector combined with the pixel-matching collimator were calculated and analyzed under different conditions. From the simulation studies, we found that such a camera using rectangular holes has promising imaging characteristics in terms of spatial resolution, detection efficiency, and energy resolution.

  4. Forecasting Global Horizontal Irradiance Using the LETKF and a Combination of Advected Satellite Images and Sparse Ground Sensors

    Science.gov (United States)

    Harty, T. M.; Lorenzo, A.; Holmgren, W.; Morzfeld, M.

    2017-12-01

    The irradiance incident on a solar panel is the main factor in determining the power output of that panel. For this reason, accurate global horizontal irradiance (GHI) estimates and forecasts are critical when determining the optimal location for a solar power plant, forecasting utility scale solar power production, or forecasting distributed, behind the meter rooftop solar power production. Satellite images provide a basis for producing the GHI estimates needed to undertake these objectives. The focus of this work is to combine satellite derived GHI estimates with ground sensor measurements and an advection model. The idea is to use accurate but sparsely distributed ground sensors to improve satellite derived GHI estimates which can cover large areas (the size of a city or a region of the United States). We use a Bayesian framework to perform the data assimilation, which enables us to produce irradiance forecasts and associated uncertainties which incorporate both satellite and ground sensor data. Within this framework, we utilize satellite images taken from the GOES-15 geostationary satellite (available every 15-30 minutes) as well as ground data taken from irradiance sensors and rooftop solar arrays (available every 5 minutes). The advection model, driven by wind forecasts from a numerical weather model, simulates cloud motion between measurements. We use the Local Ensemble Transform Kalman Filter (LETKF) to perform the data assimilation. We present preliminary results towards making such a system useful in an operational context. We explain how localization and inflation in the LETKF, perturbations of wind-fields, and random perturbations of the advection model, affect the accuracy of our estimates and forecasts. We present experiments showing the accuracy of our forecasted GHI over forecast-horizons of 15 mins to 1 hr. The limitations of our approach and future improvements are also discussed.

  5. Damage methodology approach on a composite panel based on a combination of Fringe Projection and 2D Digital Image Correlation

    Science.gov (United States)

    Felipe-Sesé, Luis; Díaz, Francisco A.

    2018-02-01

    The recent improvement in accessibility to high speed digital cameras has enabled three dimensional (3D) vibration measurements employing full-field optical techniques. Moreover, there is a need to develop a cost-effective and non-destructive testing method to quantify the severity of damages arising from impacts and thus, enhance the service life. This effect is more interesting in composite structures since possible internal damage has low external manifestation. Those possible damages have been previously studied experimentally by using vibration testing. Namely, those analyses were focused on variations in the modal frequencies or, more recently, mode shapes variations employing punctual accelerometers or vibrometers. In this paper it is presented an alternative method to investigate the severity of damage on a composite structure and how the damage affects to its integrity through the analysis of the full field modal behaviour. In this case, instead of punctual measurements, displacement maps are analysed by employing a combination of FP + 2D-DIC during vibration experiments in an industrial component. In addition, to analyse possible mode shape changes, differences between damaged and undamaged specimens are studied by employing a recent methodology based on Adaptive Image Decomposition (AGMD) procedure. It will be demonstrated that AGMD Image decomposition procedure, which decompose the displacement field into shape descriptors, is capable to detect and quantify the differences between mode shapes. As an application example, the proposed approach has been evaluated on two large industrial components (car bonnets) made of short-fibre reinforced composite. Specifically, the evolution of normalized AGMD shape descriptors has been evaluated for three different components with different damage levels. Results demonstrate the potential of the presented approach making it possible to measure the severity of a structural damage by evaluating the mode shape based in

  6. Clinical data combined with radiological imaging improves the accuracy of TNM staging of pancreatic body and tail adenocarcinoma

    Directory of Open Access Journals (Sweden)

    Xu W

    2017-10-01

    Full Text Available Wei Xu,* Bo Jiang,* Xinmin Yin* Department of Hepatobiliary Surgery, Hunan Provincial People’s Hospital, Changsha, China *These authors contributed equally to this work Purpose: Pancreatic body and tail adenocarcinoma (PBTA remains one of the deadliest cancers, and current radiological modalities still have limitations on the staging of PBTA. Improving PBTA staging will contribute to the management of this disease.Patients and methods: Clinicopathological characteristics of 91 surgically treated PBTA patients were retrospectively retrieved. Clinical data associated with postoperative tumor staging (pTNM were assessed using ordinal logistic regression model. Discriminant analysis was performed using function formula based on multivariate analysis results; further cross-validation was conducted by Bootstrap methods.Results: Multivariate analysis showed that carbohydrate antigen 19-9 ≥955.0 U/L, albumin, and alkaline phosphatase/total bilirubin ratio were independent factors contributing to improved accuracy of pTNM staging. Discriminant analysis exhibited better performance and showed that the probability of accurate prediction of pTNM stage was 90.6% and the probability of cross-validation was 85.9%. After excluding patients with preoperative diagnosis of stage IV disease, the probability of accurate prediction of pTNM stage was 86.1% and the probability of cross-validation was 75.0%.Conclusion: The combination of imaging and clinical data has higher accuracy in staging PBTA than radiological data alone. A model proposed in this study will improve the management of PBTA. Keywords: pancreatic cancer, pancreatic body and tail adenocarcinoma, TNM staging, diagnostic imaging

  7. Noble gases in meteorites and terrestrial planets

    Science.gov (United States)

    Wacker, J. F.

    1985-01-01

    Terrestrial planets and chondrites have noble gas platforms that are sufficiently alike, especially Ne/Ar, that they may have acquired their noble gases by similar processes. Meteorites presumably obtained their noble gases during formation in the solar nebula. Adsorption onto C - the major gas carrier in chondrites - is the likely mechanism for trapping noble gases; recent laboratory simulations support this hypothesis. The story is more complex for planets. An attractive possibility is that the planets acquired their noble gases in a late accreting veneer of chondritic material. In chondrites, noble gases correlate with C, N, H, and volatile metals; by Occam's Razor, we would expect a similar coupling in planets. Indeed, the Earth's crust and mantle contain chondritic like trace volatiles and PL group metals, respectively and the Earth's oceans resemble C chondrites in their enrichment of D (8X vs 8-10X of the galactic D/H ratio). Models have been proposed to explain some of the specific noble gas patterns in planets. These include: (1) noble gases may have been directly trapped by preplanetary material instead of arriving in a veneer; (2) for Venus, irradiation of preplanetary material, followed by diffusive loss of Ne, could explain the high concentration of AR-36; (3) the Earth and Venus may have initially had similar abundances of noble gases, but the Earth lost its share during the Moon forming event; (4) noble gases could have been captured by planetestimals, possibly leading to gravitational fractionation, particularly of Xe isotopes and (5) noble gases may have been dissolved in the hot outer portion of the Earth during contact with a primordial atmosphere.

  8. Tissue Doppler Imaging Combined with Advanced 12-Lead ECG Analysis Might Improve Early Diagnosis of Hypertrophic Cardiomyopathy in Childhood

    Science.gov (United States)

    Femlund, E.; Schlegel, T.; Liuba, P.

    2011-01-01

    Optimization of early diagnosis of childhood hypertrophic cardiomyopathy (HCM) is essential in lowering the risk of HCM complications. Standard echocardiography (ECHO) has shown to be less sensitive in this regard. In this study, we sought to assess whether spatial QRS-T angle deviation, which has shown to predict HCM in adults with high sensitivity, and myocardial Tissue Doppler Imaging (TDI) could be additional tools in early diagnosis of HCM in childhood. Methods: Children and adolescents with familial HCM (n=10, median age 16, range 5-27 years), and without obvious hypertrophy but with heredity for HCM (n=12, median age 16, range 4-25 years, HCM or sudden death with autopsy-verified HCM in greater than or equal to 1 first-degree relative, HCM-risk) were additionally investigated with TDI and advanced 12-lead ECG analysis using Cardiax(Registered trademark) (IMED Co Ltd, Budapest, Hungary and Houston). Spatial QRS-T angle (SA) was derived from Kors regression-related transformation. Healthy age-matched controls (n=21) were also studied. All participants underwent thorough clinical examination. Results: Spatial QRS-T angle (Figure/ Panel A) and septal E/Ea ratio (Figure/Panel B) were most increased in HCM group as compared to the HCM-risk and control groups (p less than 0.05). Of note, these 2 variables showed a trend toward higher levels in HCM-risk group than in control group (p=0.05 for E/Ea and 0.06 for QRS/T by ANOVA). In a logistic regression model, increased SA and septal E/Ea ratio appeared to significantly predict both the disease (Chi-square in HCM group: 9 and 5, respectively, p less than 0.05 for both) and the risk for HCM (Chi-square in HCM-risk group: 5 and 4 respectively, p less than 0.05 for both), with further increased predictability level when these 2 variables were combined (Chi-square 10 in HCM group, and 7 in HCM-risk group, p less than 0.01 for both). Conclusions: In this small material, Tissue Doppler Imaging and spatial mean QRS-T angle

  9. In the assessment of supratentorial glioma grade: The combined role of multivoxel proton MR spectroscopy and diffusion tensor imaging

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Q.-G. [Department of Neuroradiology, Union hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Xu, H.-B., E-mail: xuhaibo1120@hotmail.com [Department of Neuroradiology, Union hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Liu, F.; Guo, W. [Department of Neuroradiology, Union hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Kong, X.-C. [Department of Imaging technology, Union hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Wu, Y. [Department of Maternal and Child Health Care, Public Health School, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China)

    2011-10-15

    Aim: To detect a difference in the parameters derived from proton magnetic resonance spectroscopy ({sup 1}H-MRS) and diffusion tensor imaging (DTI) between low-grade and high-grade gliomas, and to evaluate whether the combination of these two techniques can improve the diagnostic accuracy of conventional magnetic resonance imaging (MRI) in supratentorial glioma grading. Materials and methods: Thirty patients with histologically proved supratentorial brain gliomas (12 low grade, 18 high grade) were prospectively evaluated with contrast material-enhanced MRI, DTI, and multivoxel {sup 1}H-MRS (135 ms echo time). The tumour grades determined using the three methods were then compared with those obtained at histopathology. Receiver operating characteristic (ROC) analyses were performed to determine the optimum thresholds for glioma grading. Independent sample t-test, Spearman's rank correlation, and the Fisher's exact test were also carried out for statistical analysis. p < 0.05 was considered statistically significant. Results: Statistically significant differences were found between the low-grade and high-grade gliomas for the choline (Cho)/creatine (Cr), N-acetylaspartate (NAA)/Cr, NAA/Cho ratio in the tumours (p < 0.01), apparent diffusion coefficient (ADC) value (p < 0.01), and fractional anisotropy (FA) value (p < 0.05) in the tumours. The NAA/Cr and NAA/Cho ratios and the calculated ADC value significantly correlated with the histological grading of the gliomas (p < 0.01). Using a threshold value of 0.66 for tumour NAA/Cr, 0.265 for NAA/Cho, 1118.1 x 10{sup -6} mm{sup 2}/s for the calculated ADC value, corresponding to the maximum Youden index from the ROC curve of the above-selected parameters, the resultant sensitivities, specificities, positive predictive values (PPVs), negative predictive values (NPVs), and Kappa values were all higher and the fraction of misclassified tumour was lower when compared with conventional MRI. However, only NAA/Cho and

  10. Greenhouse gases study in Amazonia

    International Nuclear Information System (INIS)

    D'Amelio, Monica Tais Siqueira

    2006-01-01

    The Amazon plays an important role on the global carbon cycle, as changing as carbon storage, since Amazon Basin is the biggest area of tropical forest, around 50% of global. Natural's process, deforestation, and use land are CO 2 sources. The Amazon forest is a significant source of N 2 O by soil process, and CH 4 by anaerobic process like flooded areas, rice cultures, and others sources. This project is part of the LBA project (Large-Scale Biosphere Atmosphere Experiment in Amazonia), and this project is 'Vertical profiles of carbon dioxide and other trace gas species over the Amazon basin using small aircraft'. Since December 2000 vertical profiles of CO 2 , CH 4 , CO, H 2 , N 2 O and SF 6 have been measured above central Amazonia. The local sampling was over Tapajos National Forest, a primary forest in Para State, where had a CO 2 flux tower and an east impact area with sources like animals, rice cultivation, biomass burning, etc, to compare the influence of an impact area and a preserved area in the profiles. The Reserva Biologica de Cuieiras, at Amazon State, is the other studied place, where there already exists a CO 2 flux tower, and an east preserved area at this State, to compare with the Cuieiras. The sampling has been carried out on vertical profile from 1000 ft up to 12000 ft using a semi-automated sampling package developed at GMD/NOAA and a small aircraft. The analysis uses the MAGICC system (Multiple Analysis of Gases Influence Climate Change) which is installed at the Atmospheric Chemistry Laboratory (LQA) in IPEN (Instituto de Pesquisas Energeticas e Nucleares). The results showed that all gases studied, except H 2 gas, has been following the global trend. At the Para State, for the studied years, the Amazonian Forest performed as small CO 2 sink. To compare Wet and Dry Seasons, subtracted the Ascension concentration values in the period to remove the global influence. So that, in the 2004 and 2005 wet seasons and 2004 dry season comparison it was

  11. Dipolar quantum gases of erbium

    International Nuclear Information System (INIS)

    Frisch, A.

    2014-01-01

    Since the preparation of the first Bose-Einstein condensate about two decades ago and the first degenerate Fermi gas following four years later a plethora of fascinating quantum phenomena have been explored. The vast majority of experiments focused on quantum degenerate atomic gases with short-range contact interaction between particles. Atomic species with large magnetic dipole moments, such as chromium, dysprosium, and erbium, offer unique possibilities to investigate phenomena arising from dipolar interaction. This kind of interaction is not only long-range but also anisotropic in character and imprints qualitatively novel features on the system. Prominent examples are the d-wave collapse of a dipolar Bose-Einstein condensate of chromium atoms realized by the group in Stuttgart, the spin magnetization and demagnetization dynamics observed by groups in Stuttgart, Paris, and Stanford, and the deformation of the Fermi surface observed by our group in Innsbruck. This thesis reports on the creation and study of the first Bose-Einstein condensate and degenerate Fermi gas of erbium atoms. Erbium belongs to the lanthanide group of elements and has a large magnetic moment of seven Bohr magneton. In particular, this thesis describes the experimental apparatus and the sequence for producing a dipolar quantum gas. There is an emphasis on the production of the narrow-line magneto-optical trap of erbium since this represents a very efficient and robust laser-cooling scheme that greatly simplifies the experimental procedure. After describing the experimental setup this thesis focuses on several fundamental questions related to the dipolar character of erbium and to its lanthanide nature. A first set of studies centers on the scattering properties of ultracold erbium atoms, including the elastic and the inelastic cross section and the spectrum of Feshbach resonances. Specifically, we observe that identical dipolar fermions do collide and rethermalize even at low temperatures

  12. Diagnostic role of (99)Tc(m)-MDP SPECT/CT combined SPECT/MRI Multi modality imaging for early and atypical bone metastases.

    Science.gov (United States)

    Chen, Xiao-Liang; Li, Qian; Cao, Lin; Jiang, Shi-Xi

    2014-01-01

    The bone metastasis appeared early before the bone imaging for most of the above patients. (99)Tc(m)-MDP ((99)Tc(m) marked methylene diphosphonate) bone imaging could diagnosis the bone metastasis with highly sensitivity, but with lower specificity. The aim of this study is to explore the diagnostic value of (99)Tc(m)-MDP SPECT/CT combined SPECT/MRI Multi modality imaging for the early period atypical bone metastases. 15 to 30 mCi (99)Tc(m)-MDP was intravenously injected to the 34 malignant patients diagnosed as doubtful early bone metastases. SPECT, CT and SPECT/CT images were captured and analyzed consequently. For the patients diagnosed as early period atypical bone metastases by SPECT/CT, combining the SPECT/CT and MRI together as the SPECT/MRI integrated image. The obtained SPECT/MRI image was analyzed and compared with the pathogenic results of patients. The results indicated that 34 early period doubtful metastatic focus, including 34 SPECT positive focus, 17 focus without special changes by using CT method, 11 bone metastases focus by using SPECT/CT method, 23 doubtful bone metastases focus, 8 doubtful bone metastases focus, 14 doubtful bone metastases focus and 2 focus without clear image. Totally, SPECT/CT combined with SPECT/MRI method diagnosed 30 bone metastatic focus and 4 doubtfully metastatic focus. In conclusion, (99)Tc(m)-MDP SPECT/CT combined SPECT/MRI Multi modality imaging shows a higher diagnostic value for the early period bone metastases, which also enhances the diagnostic accuracy rate.

  13. Imaging volcanic CO2 and SO2

    Science.gov (United States)

    Gabrieli, A.; Wright, R.; Lucey, P. G.; Porter, J. N.

    2017-12-01

    Detecting and quantifying volcanic carbon dioxide (CO2) and sulfur dioxide (SO2) emissions is of relevance to volcanologists. Changes in the amount and composition of gases that volcanoes emit are related to subsurface magma movements and the probability of eruptions. Volcanic gases and related acidic aerosols are also an important atmospheric pollution source that create environmental health hazards for people, animals, plants, and infrastructures. For these reasons, it is important to measure emissions from volcanic plumes during both day and night. We present image measurements of the volcanic plume at Kīlauea volcano, HI, and flux derivation, using a newly developed 8-14 um hyperspectral imaging spectrometer, the Thermal Hyperspectral Imager (THI). THI is capable of acquiring images of the scene it views from which spectra can be derived from each pixel. Each spectrum contains 50 wavelength samples between 8 and 14 um where CO2 and SO2 volcanic gases have diagnostic absorption/emission features respectively at 8.6 and 14 um. Plume radiance measurements were carried out both during the day and the night by using both the lava lake in the Halema'uma'u crater as a hot source and the sky as a cold background to detect respectively the spectral signatures of volcanic CO2 and SO2 gases. CO2 and SO2 path-concentrations were then obtained from the spectral radiance measurements using a new Partial Least Squares Regression (PLSR)-based inversion algorithm, which was developed as part of this project. Volcanic emission fluxes were determined by combining the path measurements with wind observations, derived directly from the images. Several hours long time-series of volcanic emission fluxes will be presented and the SO2 conversion rates into aerosols will be discussed. The new imaging and inversion technique, discussed here, are novel allowing for continuous CO2 and SO2 plume mapping during both day and night.

  14. The Combination of In vivo (124)I-PET and CT Small Animal Imaging for Evaluation of Thyroid Physiology and Dosimetry.

    Science.gov (United States)

    El-Ali, Henrik H; Eckerwall, Martin; Skovgaard, Dorthe; Larsson, Erik; Strand, Sven-Erik; Kjaer, Andreas

    2012-06-05

    A thyroid rat model combining functional and anatomical information would be of great benefit for better modeling of thyroid physiology and for absorbed dose calculations. Our aim was to show that (124)I-PET and CT small animal imaging are useful as a combined model for studying thyroid physiology and dose calculation. Seven rats were subjects for multiple thyroid (124)I-imaging and CT-scans. S-values [mGy/MBqs] for different thyroid sizes were simulated. A phantom with spheres was designed for validation of performances of the small animal PET and CT imaging systems. Small animal image-based measurements of the activity amount and the volumes of the spheres with a priori known volumes showed a good agreement with their corresponding actual volumes. The CT scans of the rats showed thyroid volumes from 34-70 mL. The wide span in volumes of thyroid glands indicates the importance of using an accurate volume-measuring technique such as the small animal CT. The small animal PET system was on the other hand able to accurately estimate the activity concentration in the thyroid volumes. We conclude that the combination of the PET and CT image information is essential for quantitative thyroid imaging and accurate thyroid absorbed dose calculation.

  15. The Combination of In vivo 124I-PET and CT Small Animal Imaging for Evaluation of Thyroid Physiology and Dosimetry

    Directory of Open Access Journals (Sweden)

    Henrik H. El-Ali

    2012-06-01

    Full Text Available Objective: A thyroid rat model combining functional and anatomical information would be of great benefit for better modeling of thyroid physiology and for absorbed dose calculations. Our aim was to show that 124I-PET and CT small animal imaging are useful as a combined model for studying thyroid physiology and dose calculation. Methods: Seven rats were subjects for multiple thyroid 124I-imaging and CT-scans. S-values [mGy/MBqs] for different thyroid sizes were simulated. A phantom with spheres was designed for validation of performances of the small animal PET and CT imaging systems. Results: Small animal image-based measurements of the activity amount and the volumes of the spheres with a priori known volumes showed a good agreement with their corresponding actual volumes. The CT scans of the rats showed thyroid volumes from 34–70 mL. Conclusions: The wide span in volumes of thyroid glands indicates the importance of using an accurate volume-measuring technique such as the small animal CT. The small animal PET system was on the other hand able to accurately estimate the activity concentration in the thyroid volumes. We conclude that the combination of the PET and CT image information is essential for quantitative thyroid imaging and accurate thyroid absorbed dose calculation.

  16. Biofilm imaging in porous media by laboratory X-Ray tomography: Combining a non-destructive contrast agent with propagation-based phase-contrast imaging tools.

    Science.gov (United States)

    Carrel, Maxence; Beltran, Mario A; Morales, Verónica L; Derlon, Nicolas; Morgenroth, Eberhard; Kaufmann, Rolf; Holzner, Markus

    2017-01-01

    X-ray tomography is a powerful tool giving access to the morphology of biofilms, in 3D porous media, at the mesoscale. Due to the high water content of biofilms, the attenuation coefficient of biofilms and water are very close, hindering the distinction between biofilms and water without the use of contrast agents. Until now, the use of contrast agents such as barium sulfate, silver-coated micro-particles or 1-chloronaphtalene added to the liquid phase allowed imaging the biofilm 3D morphology. However, these contrast agents are not passive and potentially interact with the biofilm when injected into the sample. Here, we use a natural inorganic compound, namely iron sulfate, as a contrast agent progressively bounded in dilute or colloidal form into the EPS matrix during biofilm growth. By combining a very long source-to-detector distance on a X-ray laboratory source with a Lorentzian filter implemented prior to tomographic reconstruction, we substantially increase the contrast between the biofilm and the surrounding liquid, which allows revealing the 3D biofilm morphology. A comparison of this new method with the method proposed by Davit et al (Davit et al., 2011), which uses barium sulfate as a contrast agent to mark the liquid phase was performed. Quantitative evaluations between the methods revealed substantial differences for the volumetric fractions obtained from both methods. Namely, contrast agent-biofilm interactions (e.g. biofilm detachment) occurring during barium sulfate injection caused a reduction of the biofilm volumetric fraction of more than 50% and displacement of biofilm patches elsewhere in the column. Two key advantages of the newly proposed method are that passive addition of iron sulfate maintains the integrity of the biofilm prior to imaging, and that the biofilm itself is marked by the contrast agent, rather than the liquid phase as in other available methods. The iron sulfate method presented can be applied to understand biofilm development

  17. Biofilm imaging in porous media by laboratory X-Ray tomography: Combining a non-destructive contrast agent with propagation-based phase-contrast imaging tools.

    Directory of Open Access Journals (Sweden)

    Maxence Carrel

    Full Text Available X-ray tomography is a powerful tool giving access to the morphology of biofilms, in 3D porous media, at the mesoscale. Due to the high water content of biofilms, the attenuation coefficient of biofilms and water are very close, hindering the distinction between biofilms and water without the use of contrast agents. Until now, the use of contrast agents such as barium sulfate, silver-coated micro-particles or 1-chloronaphtalene added to the liquid phase allowed imaging the biofilm 3D morphology. However, these contrast agents are not passive and potentially interact with the biofilm when injected into the sample. Here, we use a natural inorganic compound, namely iron sulfate, as a contrast agent progressively bounded in dilute or colloidal form into the EPS matrix during biofilm growth. By combining a very long source-to-detector distance on a X-ray laboratory source with a Lorentzian filter implemented prior to tomographic reconstruction, we substantially increase the contrast between the biofilm and the surrounding liquid, which allows revealing the 3D biofilm morphology. A comparison of this new method with the method proposed by Davit et al (Davit et al., 2011, which uses barium sulfate as a contrast agent to mark the liquid phase was performed. Quantitative evaluations between the methods revealed substantial differences for the volumetric fractions obtained from both methods. Namely, contrast agent-biofilm interactions (e.g. biofilm detachment occurring during barium sulfate injection caused a reduction of the biofilm volumetric fraction of more than 50% and displacement of biofilm patches elsewhere in the column. Two key advantages of the newly proposed method are that passive addition of iron sulfate maintains the integrity of the biofilm prior to imaging, and that the biofilm itself is marked by the contrast agent, rather than the liquid phase as in other available methods. The iron sulfate method presented can be applied to understand

  18. Combined use of X-ray fluorescence microscopy, phase contrast imaging for high resolution quantitative iron mapping in inflamed cells

    Science.gov (United States)

    Gramaccioni, C.; Procopio, A.; Farruggia, G.; Malucelli, E.; Iotti, S.; Notargiacomo, A.; Fratini, M.; Yang, Y.; Pacureanu, A.; Cloetens, P.; Bohic, S.; Massimi, L.; Cutone, A.; Valenti, P.; Rosa, L.; Berlutti, F.; Lagomarsino, S.

    2017-06-01

    X-ray fluorescence microscopy (XRFM) is a powerful technique to detect and localize elements in cells. To derive information useful for biology and medicine, it is essential not only to localize, but also to map quantitatively the element concentration. Here we applied quantitative XRFM to iron in phagocytic cells. Iron, a primary component of living cells, can become toxic when present in excess. In human fluids, free iron is maintained at 10-18 M concentration thanks to iron binding proteins as lactoferrin (Lf). The iron homeostasis, involving the physiological ratio of iron between tissues/secretions and blood, is strictly regulated by ferroportin, the sole protein able to export iron from cells to blood. Inflammatory processes induced by lipopolysaccharide (LPS) or bacterial pathoge inhibit ferroportin synthesis in epithelial and phagocytic cells thus hindering iron export, increasing intracellular iron and bacterial multiplication. In this respect, Lf is emerging as an important regulator of both iron and inflammatory homeostasis. Here we studied phagocytic cells inflamed by bacterial LPS and untreated or treated with milk derived bovine Lf. Quantitative mapping of iron concentration and mass fraction at high spatial resolution is obtained combining X-ray fluorescence microscopy, atomic force microscopy and synchrotron phase contrast imaging.

  19. Structural brain alterations in bipolar disorder II: a combined voxel-based morphometry (VBM) and diffusion tensor imaging (DTI) study.

    Science.gov (United States)

    Ambrosi, Elisa; Rossi-Espagnet, Maria Camilla; Kotzalidis, Georgios D; Comparelli, Anna; Del Casale, Antonio; Carducci, Filippo; Romano, Andrea; Manfredi, Giovanni; Tatarelli, Roberto; Bozzao, Alessandro; Girardi, Paolo

    2013-09-05

    Brain structural changes have been described in bipolar disorder (BP), but usually studies focused on both I and II subtypes indiscriminately and investigated changes in either brain volume or white matter (WM) integrity. We used combined voxel-based morphometry (VBM) and diffusion tensor imaging (DTI) analysis to track changes in the grey matter (GM) and WM in the brains of patients affected by BPII, as compared to healthy controls. Using VBM and DTI, we scanned 20 DSM-IV-TR BPII patients in their euthymic phase and 21 healthy, age- and gender-matched volunteers with no psychiatric history. VBM showed decreases in GM of BPII patients, compared to controls, which were diffuse in nature and most prominent in the right middle frontal gyrus and in the right superior temporal gurus. DTI showed significant and widespread FA reduction in BPII patients in all major WM tracts, including cortico-cortical association tracts. The small sample size limits the generalisability of our findings. Reduced GM volumes and WM integrity changes in BPII patients are not prominent like those previously reported in bipolar disorder type-I and involve cortical structures and their related association tracts. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Combined low-temperature scanning tunneling/atomic force microscope for atomic resolution imaging and site-specific force spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Schwarz, Udo; Albers, Boris J.; Liebmann, Marcus; Schwendemann, Todd C.; Baykara, Mehmet Z.; Heyde, Markus; Salmeron, Miquel; Altman, Eric I.; Schwarz, Udo D.

    2008-02-27

    The authors present the design and first results of a low-temperature, ultrahigh vacuum scanning probe microscope enabling atomic resolution imaging in both scanning tunneling microscopy (STM) and noncontact atomic force microscopy (NC-AFM) modes. A tuning-fork-based sensor provides flexibility in selecting probe tip materials, which can be either metallic or nonmetallic. When choosing a conducting tip and sample, simultaneous STM/NC-AFM data acquisition is possible. Noticeable characteristics that distinguish this setup from similar systems providing simultaneous STM/NC-AFM capabilities are its combination of relative compactness (on-top bath cryostat needs no pit), in situ exchange of tip and sample at low temperatures, short turnaround times, modest helium consumption, and unrestricted access from dedicated flanges. The latter permits not only the optical surveillance of the tip during approach but also the direct deposition of molecules or atoms on either tip or sample while they remain cold. Atomic corrugations as low as 1 pm could successfully be resolved. In addition, lateral drifts rates of below 15 pm/h allow long-term data acquisition series and the recording of site-specific spectroscopy maps. Results obtained on Cu(111) and graphite illustrate the microscope's performance.

  1. Influence of the gray gases number in the weighted sum of gray gases model on the radiative heat exchange calculation inside pulverized coal-fired furnaces

    Directory of Open Access Journals (Sweden)

    Crnomarković Nenad Đ.

    2016-01-01

    Full Text Available The influence of the number of gray gases in the weighted sum in the gray gases model on the calculation of the radiative heat transfer is discussed in the paper. A computer code which solved the set of equations of the mathematical model describing the reactive two-phase turbulent flow with radiative heat exchange and with thermal equilibrium between phases inside the pulverized coal-fired furnace was used. Gas-phase radiative properties were determined by the simple gray gas model and two combinations of the weighted sum of the gray gases models: one gray gas plus a clear gas and two gray gases plus a clear gas. Investigation was carried out for two values of the total extinction coefficient of the dispersed phase, for the clean furnace walls and furnace walls covered by an ash layer deposit, and for three levels of the approximation accuracy of the weighting coefficients. The influence of the number of gray gases was analyzed through the relative differences of the wall fluxes, wall temperatures, medium temperatures, and heat transfer rate through all furnace walls. The investigation showed that there were conditions of the numerical investigations for which the relative differences of the variables describing the radiative heat exchange decrease with the increase in the number of gray gases. The results of this investigation show that if the weighted sum of the gray gases model is used, the complexity of the computer code and calculation time can be reduced by optimizing the number of gray gases. [Projekat Ministarstva nauke Republike Srbije, br. TR-33018: Increase in energy and ecology efficiency of processes in pulverized coal-fired furnace and optimization of utility steam boiler air preheater by using in-house developed software tools

  2. Voluntary reporting of greenhouse gases, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-07-01

    The Voluntary Reporting Program for greenhouse gases is part of an attempt by the U.S. Government to develop innovative, low-cost, and nonregulatory approaches to limit emissions of greenhouse gases. It is one element in an array of such programs introduced in recent years as part of the effort being made by the United States to comply with its national commitment to stabilize emissions of greenhouse gases under the Framework Convention on Climate Change. The Voluntary Reporting Program, developed pursuant to Section 1605(b) of the Energy Policy Act of 1992, permits corporations, government agencies, households, and voluntary organizations to report to the Energy Information Administration (EIA) on actions taken that have reduced or avoided emissions of greenhouse gases.

  3. Roadside management strategies to reduce greenhouse gases.

    Science.gov (United States)

    2010-06-01

    Californias Global Warming Solutions Act of 2006 (AB 32), Sustainable Communities and Climate Protection Act : (SB 375), and Executive Order S-14-08 direct Caltrans to develop actions to reduce greenhouse gases (GHGs). Air : pollution reduction is...

  4. Atomic physics: Cold gases venture into Flatland

    Science.gov (United States)

    Burnett, Keith

    2007-09-01

    Vortex structures have revealed a lot about the nature of three-dimensional Bose-Einstein condensates. They play an even bigger part in two-dimensional cold atomic gases and drive a fundamentally different phase transition.

  5. Phase space methods for degenerate quantum gases

    CERN Document Server

    Dalton, Bryan J; Barnett, Stephen M

    2015-01-01

    Recent experimental progress has enabled cold atomic gases to be studied at nano-kelvin temperatures, creating new states of matter where quantum degeneracy occurs - Bose-Einstein condensates and degenerate Fermi gases. Such quantum states are of macroscopic dimensions. This book presents the phase space theory approach for treating the physics of degenerate quantum gases, an approach already widely used in quantum optics. However, degenerate quantum gases involve massive bosonic and fermionic atoms, not massless photons. The book begins with a review of Fock states for systems of identical atoms, where large numbers of atoms occupy the various single particle states or modes. First, separate modes are considered, and here the quantum density operator is represented by a phase space distribution function of phase space variables which replace mode annihilation, creation operators, the dynamical equation for the density operator determines a Fokker-Planck equation for the distribution function, and measurable...

  6. Molecular imaging with little anatomic information: combined scintigraphic-radiologic imaging of thyroid cancer and sentinel-lymph-node; Molekulare Bildgebung bei geringer anatomischer Bildinformation: Kombinierte szintigraphisch-radiologische Darstellung beim Schilddruesenkarzinom und Sentinel-Lymph-Node

    Energy Technology Data Exchange (ETDEWEB)

    Schlemmer, H.; Jigalin, A.; Freter, B.T.; Gasthaus, K.; Langer, H.; Lerch, H. [Klinik fuer Nuklearmedizin, HELIOS Klinikum Wuppertal, Univ. Witten-Herdecke (Germany)

    2006-09-15

    The combined SPECT-CT examination is a procedure applied for acquisition, overlaying, and analysis of the scintigraphic functional data with the anatomic information in one single examination. This is considered especially for the molecular imaging with only little anatomic information. By giving examples, this elaboration demonstrates the advantages of the method of combining SPECT and radiologic presentation at the iodine-131-radio-nuclide imaging of differentiated thyroid cancer and the sentinel-lymph-node-scanning of different tumor entities. The possibility of combined imaging permits the examiner more diagnostic accuracy by better recognizing of pathologic processes with exact anatomic localisation. It is a simple examination which can be done in one process and hardly stresses the patient. (orig.)

  7. Biological production of products from waste gases

    Science.gov (United States)

    Gaddy, James L.

    2002-01-22

    A method and apparatus are designed for converting waste gases from industrial processes such as oil refining, and carbon black, coke, ammonia, and methanol production, into useful products. The method includes introducing the waste gases into a bioreactor where they are fermented to various products, such as organic acids, alcohols, hydrogen, single cell protein, and salts of organic acids by anaerobic bacteria within the bioreactor. These valuable end products are then recovered, separated and purified.

  8. TRMM Combined Precipitation Radar (PR) and TRMM Microwave Imager (TMI) Rainfall Profile Product (TRMM Product 2B31) V7

    Data.gov (United States)

    National Aeronautics and Space Administration — The TRMM Microwave Imager (TMI) is a nine-channel passive microwave radiometer, which builds on the heritage of the Special Sensor Microwave/Imager (SSM/I)...

  9. TRMM Combined Precipitation Radar (PR) and TRMM Microwave Imager (TMI) Rainfall Profile Product (TRMM Product 2B31) V6

    Data.gov (United States)

    National Aeronautics and Space Administration — The TRMM Microwave Imager (TMI) is a nine-channel passive microwave radiometer, which builds on the heritage of the Special Sensor Microwave/Imager (SSM/I)...

  10. TRMM Combined Precipitation Radar (PR) and TRMM Microwave Imager (TMI) Gridded Rainfall Product (TRMM Product 3B31) V7

    Data.gov (United States)

    National Aeronautics and Space Administration — The TRMM Microwave Imager (TMI) is a nine-channel passive microwave radiometer which builds on the heritage of the Special Sensor Microwave/Imager (SSM/I)...

  11. TRMM Combined Precipitation Radar (PR) and TRMM Microwave Imager (TMI) Gridded Rainfall Product (TRMM Product 3B31) V6

    Data.gov (United States)

    National Aeronautics and Space Administration — The TRMM Microwave Imager (TMI) is a nine-channel passive microwave radiometer which builds on the heritage of the Special Sensor Microwave/Imager (SSM/I)...

  12. Process for treating radioactive waste gases

    International Nuclear Information System (INIS)

    Yuasa, Yoshiyuki; Nagao, Hiroyuki; Takiguchi, Yukio; An, Bunzai; Tsuda, Koji.

    1975-01-01

    Object: To securely perform separation and enrichment of radioactive rare gases to store safely them for a long period of time. Structure: The wastes extracted by an air extractor are processed by a heater and a recombiner and hydrogen and oxygen are changed into water thereby and it is passed through a gas and water separator to be dewatered, after which water and carbon dioxide gas are removed by passing through a delay pipe, filter, and water- and carbon dioxide gas removing device and then fed to a lower temperature adsorbing device to adsorb and remove the radioactive rare gases. This low temperature adsorbing device is composed of two towers, one of which is designed to saturate the radioactive rare gases, which are processed by a heater and passed through a recycle line to meet raw gases. Then, it is fed to the other lower temperature adsorbing device and this cycle is repeated to enrich the radioactive rare gases. Oxygen and impurities in the enriched gases are removed by the impurity removing device and thereafter are stored in a gas holder and finally sealed in a cylinder. (Kamimura, M.)

  13. Gases and carbon in metals. Pt. 14

    International Nuclear Information System (INIS)

    Jehn, H.; Speck, H.; Hehn, W.; Fromm, E.; Hoerz, G.

    1981-01-01

    This issue is part of a series of data on 'Gases and Carbon in Metals' which supplements the data compilation in the book 'Gase und Kohlenstoff in Metallen' (Gases and Carbon in Metals), edited by E. Fromm and E. Gebhardt, Springer-Verlag, Berlin 1976. The present survey includes results from papers published after the copy deadline and recommends critically selected data. Furthermore, it comprises a bibliography of relevant literature. For each element, firstly data on binary systems are presented, starting with hydrogen and followed by carbon, nitrogen, oxygen, and rare gases. Within one metal-metalloid system the data are listed under topics such as solubility, solubility limit, dissociation pressure of compounds, vapour pressure of volatile oxides, thermodynamic data, diffusion, transport parameters (effective valence, heat of transport), permeation of gases through metals, gas absorption and gas desorption kinetics, compound formation kinetics, precipitation kinetics, and property changes. Following the data on binary systems, the data of ternary systems are presented, beginning with systems which contain one metal and two gases or one gas and carbon and continuing with systems with two metals and one gas or carbon. (orig./GE)

  14. Quantum statistics of dense gases and nonideal plasmas

    CERN Document Server

    Ebeling, Werner; Filinov, Vladimir

    2017-01-01

    The aim of this book is the pedagogical exploration of the basic principles of quantum-statistical thermodynamics as applied to various states of matter – ranging from rare gases to astrophysical matter with high-energy density. The reader will learn in this work that thermodynamics and quantum statistics are still the concepts on which even the most advanced research is operating - despite of a flood of modern concepts, classical entities like temperature, pressure, energy and entropy are shown to remain fundamental. The physics of gases, plasmas and high-energy density matter is still a growing field and even though solids and liquids dominate our daily life, more than 99 percent of the visible Universe is in the state of gases and plasmas and the overwhelming part of matter exists at extreme conditions connected with very large energy densities, such as in the interior of stars. This text, combining material from lectures and advanced seminars given by the authors over many decades, is a must-have intr...

  15. Risk stratification of patients with combined acute pulmonary embolism and pulmonary hypertension using dynamic and regular pulmonary perfusion imaging

    International Nuclear Information System (INIS)

    Wang Xuemei; Wang Jing; Li Guohua; Wang Xiangcheng; Zhang Kaixiu; Liu Caiping

    2010-01-01

    Objective: To stratify the risks of patients with acute pulmonary embolism (APE) and pulmonary hypertension (PH) by dynamic pulmonary perfusion imaging (DPPI) and pulmonary perfusion imaging (PPI). Methods: From October 2007 to February 2009, 20 healthy volunteers (12 males, 8 females; mean age =48.47±13.47 years) and 31 APE patients (21 males, 10 females; mean age =47.68±18.06 years; from October 2007 to July 2009) were included in the study. DPPI and PPI were performed in all subjects. Percentage of perfusion defect scores (PPDs%) were calculated by semi-quantitative analysis of PPI. Risk levels were defined according to PPDs% calculated from PPI: normal (PPDs% =0); very low risk (0 60%). Lung equilibrium time (LET) was calculated on region of interest (ROI) drawn over DPPI. Clinical risk was scored by Aujesky method.The t-test, ANOVA and correlation analysis were used with SPSS 13.0 software. Results: (1) LET in healthy volunteers and APE patients was (12.18±3.28) and (32.90±14.29) s respectively (t = 6.81, P<0.01). (2) The correlation coefficient, coefficient of determination between LET and PPDs% in APE patients were 0.93 and 0.87, respectively. The correlation coefficient between LET and clinical risk score was 0.86. (3) The mean LET of APE patients in very low risk (n =5), low risk (n = 12), moderate risk (n=9), high risk (n=4) and very high risk groups (n=1) were (19.59 ±0.04), (25.03±0.08), (36.07±0.10), (57.15±0.06) and (70±0.00) s, respectively. There was significant difference among APE patients with different risk levels (F =16.78, P<0.01). Conclusions: (1) DPPI was a reliable, convenient and non-invasive method for the evaluation of PH in APE. (2) Combined LET of DPPI and PPDs% of PPI was valuable for risk stratification and prognosis estimation in APE patients. (authors)

  16. Investigation of the degradation mechanisms of a variety of organic photovoltaic devices by combination of imaging techniques—the ISOS-3 inter-laboratory collaboration

    DEFF Research Database (Denmark)

    Rösch, Roland; Tanenbaum, David; Jørgensen, Mikkel

    2012-01-01

    The investigation of degradation of seven distinct sets (with a number of individual cells of n $ 12) of state of the art organic photovoltaic devices prepared by leading research laboratories with a combination of imaging methods is reported. All devices have been shipped to and degraded at Risø...

  17. Feasibility of 3D navigator-triggered magnetic resonance cholangiopancreatography with combined parallel imaging and compressed sensing reconstruction at 3T.

    Science.gov (United States)

    Seo, Nieun; Park, Mi-Suk; Han, Kyunghwa; Kim, Dongeun; King, Kevin F; Choi, Jin-Young; Kim, Honsoul; Kim, Hye Jin; Lee, Minsu; Bae, Heejin; Kim, Myeong-Jin

    2017-11-01

    To assess the feasibility of 3D navigator-triggered magnetic resonance cholangiopancreatography (MRCP) with combined parallel imaging (PI) and compressed sensing (CS). With Institutional Review Board approval, 30 consecutive patients who underwent MRCP for suspected pancreaticobiliary disease were prospectively recruited. All patients underwent 3D navigator-triggered MRCP with conventional PI alone, and with combined PI and CS using a 3T machine. The acquisition time and relative duct-to-periductal contrast ratios (RCs) at three biliary segments were quantitatively compared between the two MRCP methods. Qualitative image parameters were independently evaluated by two blinded radiologists, and were compared between two methods using the Wilcoxon signed-rank test. The mean acquisition time of MRCP with combined PI and CS (131.87 ± 33.60 sec) was significantly shorter compared with that of MRCP with PI (253.63 ± 56.08 sec; P 0.999). Combined PI and CS reconstruction is feasible for 3D navigator-triggered MRCP, providing image quality comparable to that of MRCP with PI alone, in about half the acquisition time. 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2017;46:1289-1297. © 2017 International Society for Magnetic Resonance in Medicine.

  18. Combining the Pixel-based and Object-based Methods for Building Change Detection Using High-resolution Remote Sensing Images

    Directory of Open Access Journals (Sweden)

    ZHANG Zhiqiang

    2018-01-01

    Full Text Available Timely and accurate change detection of buildings provides important information for urban planning and management.Accompanying with the rapid development of satellite remote sensing technology,detecting building changes from high-resolution remote sensing images have received wide attention.Given that pixel-based methods of change detection often lead to low accuracy while object-based methods are complicated for uses,this research proposes a method that combines pixel-based and object-based methods for detecting building changes from high-resolution remote sensing images.First,based on the multiple features extracted from the high-resolution images,a random forest classifier is applied to detect changed building at the pixel level.Then,a segmentation method is applied to segement the post-phase remote sensing image and to get post-phase image objects.Finally,both changed building at the pixel level and post-phase image objects are fused to recognize the changed building objects.Multi-temporal QuickBird images are used as experiment data for building change detection with high-resolution remote sensing images,the results indicate that the proposed method could reduce the influence of environmental difference,such as light intensity and view angle,on building change detection,and effectively improve the accuracies of building change detection.

  19. Construction of a laser combiner for dual fluorescent single molecule imaging of pRNA of phi29 DNA packaging motor.

    Science.gov (United States)

    Zhang, Hui; Shu, Dan; Browne, Mark; Guo, Peixuan

    2010-02-01

    A customized laser combiner was designed and constructed for dual channel single molecule imaging. The feasibility of a combiner-incorporated imaging system was demonstrated in studies of single molecule FRET. Distance rulers made of dual-labeled dsDNA were used to evaluate the system by determining the distance between one FRET pair. The results showed that the system is sensitive enough to distinguish between distances differing by two base pair and the distances calculated from FRET efficiencies are close to those documented in the literature. The single molecule FRET with the dual-color imaging system was also applied to reconstructed phi29 motor pRNA monomers. Finally, techniques for dual laser alignment and tuning of laser power for dual-color excitation are discussed.

  20. Imaging of treatment response to the combination of carboplatin and paclitaxel in human ovarian cancer xenograft tumors in mice using FDG and FLT PET

    DEFF Research Database (Denmark)

    Munk Jensen, Mette; Erichsen, Kamille Dumong; Björkling, Fredrik

    2013-01-01

    A combination of carboplatin and paclitaxel is often used as first line chemotherapy for treatment of ovarian cancer. Therefore the use of imaging biomarkers early after initiation of treatment to determine treatment sensitivity would be valuable in order to identify responders from non-responder......A combination of carboplatin and paclitaxel is often used as first line chemotherapy for treatment of ovarian cancer. Therefore the use of imaging biomarkers early after initiation of treatment to determine treatment sensitivity would be valuable in order to identify responders from non......-responders. In this study we describe the non-invasive PET imaging of glucose uptake and cell proliferation using 2-deoxy-2-[(18)F]fluoro-D-glucose (FDG) and 3'-deoxy-3'-[(18)F]fluorothymidine (FLT) for early assessment of treatment response in a pre-clinical mouse model of human ovarian cancer treated with carboplatin...

  1. Combining deep learning and coherent anti-Stokes Raman scattering imaging for automated differential diagnosis of lung cancer

    Science.gov (United States)

    Weng, Sheng; Xu, Xiaoyun; Li, Jiasong; Wong, Stephen T. C.

    2017-10-01

    Lung cancer is the most prevalent type of cancer and the leading cause of cancer-related deaths worldwide. Coherent anti-Stokes Raman scattering (CARS) is capable of providing cellular-level images and resolving pathologically related features on human lung tissues. However, conventional means of analyzing CARS images requires extensive image processing, feature engineering, and human intervention. This study demonstrates the feasibility of applying a deep learning algorithm to automatically differentiate normal and cancerous lung tissue images acquired by CARS. We leverage the features learned by pretrained deep neural networks and retrain the model using CARS images as the input. We achieve 89.2% accuracy in classifying normal, small-cell carcinoma, adenocarcinoma, and squamous cell carcinoma lung images. This computational method is a step toward on-the-spot diagnosis of lung cancer and can be further strengthened by the efforts aimed at miniaturizing the CARS technique for fiber-based microendoscopic imaging.

  2. Trace gases and other potential perturbations to global climate

    International Nuclear Information System (INIS)

    Wang, W.; Wuebbles, D.J.; Washington, W.M.; Isaacs, R.G.; Molnar, G.

    1986-01-01

    We review the various natural and anthropogenic factors that may affect the climate. The purpose is to summarize our understanding of these factors and their potential future climatic effects so that CO 2 -induced climate change can be viewed in a proper context. The factors we discuss include trace gases, anthropogenic and volcanic aerosols, variation of solar constant, change of surface characteristics, and releases of waste heat. We discuss the origins of the various natural and anthropogenic perturbations, the physical and chemical processes and their interactions, model sensitivity calculations, and model projections of their potential future climatic effects. The discussions center on trace gases because of their potentially large climatic effects. It appears that the increases of atmospheric trace gases of other kinds in addition to CO 2 could have important climatic effects. The model calculations suggest that the combined effect of these other trace gases, and the associated change of atmospheric ozone and water vapor distributions, could potentially warm the climate by an amount comparable in magnitude to the effect of doubling the CO 2 . Aerosols of anthropogenic origins may have substantial effects on regional climate, while the volcanic aerosols may have an effect on large-scale climate for up to a few years after injection. Changes of surface characteristics and releases of waste heat may also have substantial effects on the regional climate, but these effects are most likely to be small when compared with the effect of CO 2 increase. Changes of solar constant could have an effect on the global scale, but the time scale is much longer. There is much more that needs to be learned with regard to the above mentioned natural and anthropogenic factors that may affect the climate. A brief summary of those needs is presented

  3. New algorithm to determine true colocalization in combination with image restoration and time-lapse confocal microscopy to MAP kinases in mitochondria.

    Directory of Open Access Journals (Sweden)

    Jorge Ignacio Villalta

    Full Text Available The subcellular localization and physiological functions of biomolecules are closely related and thus it is crucial to precisely determine the distribution of different molecules inside the intracellular structures. This is frequently accomplished by fluorescence microscopy with well-characterized markers and posterior evaluation of the signal colocalization. Rigorous study of colocalization requires statistical analysis of the data, albeit yet no single technique has been established as a standard method. Indeed, the few methods currently available are only accurate in images with particular characteristics. Here, we introduce a new algorithm to automatically obtain the true colocalization between images that is suitable for a wide variety of biological situations. To proceed, the algorithm contemplates the individual contribution of each pixel's fluorescence intensity in a pair of images to the overall Pearsońs correlation and Manders' overlap coefficients. The accuracy and reliability of the algorithm was validated on both simulated and real images that reflected the characteristics of a range of biological samples. We used this algorithm in combination with image restoration by deconvolution and time-lapse confocal microscopy to address the localization of MEK1 in the mitochondria of different cell lines. Appraising the previously described behavior of Akt1 corroborated the reliability of the combined use of these techniques. Together, the present work provides a novel statistical approach to accurately and reliably determine the colocalization in a variety of biological images.

  4. Satellite Images Combined with Field Data Reveal Negative Changes in the Distribution of Babassu Palms after Clearing off Amazonian Forests

    Science.gov (United States)

    Mitja, D.; Delaître, E.; Santos, A. M.; Miranda, I.; Coelho, R. F. R.; Macedo, D. J.; Demagistri, L.; Petit, M.

    2018-02-01

    When the Amazonian rain forest is cut to create pasture, some of the original vegetal species survive clearing, even expressing their ability to invade agro-systems. It is true of the babassu palm, which can be considered, paradoxically, a natural resource by the "Interstate Movement of Babassu Fruit Breaker Women" or as native weed by land owners-farmers. To manage potential conflict of land uses, we study here the current density of this palm tree in different habitats, based on a combination of field data and remote sensing data. Firstly, we checked that the field survey methodology (i.e., counting free-trunk palm trees over 20 cm in circumference) provides density values compatible with those stemming from satellite images interpretation. We can see then that, a PA-Benfica Brazilian territory revealed an average density of the babassu lower in pastures (2.86 ind/ha) than in the dense forest (4.72 ind/ha) from which they originate and than in fallow land (4.31 ind/ha). We analyze in detail density data repartition in three habitats and we discuss results from the literature on the density of this palm tree versus its resilience at different developmental stages after forest clearing, depending on anthropogenic—or not—factors, including solar radiation, fire, weeding, clear cutting, burying fruit, and competition with forage grass. All these results can be exploited for the design of future management plans for the babassu palm and we think that the linked methodology and interdisciplinary approach can be extended to others palms and trees species in similar problematic issues.

  5. Myocardial lipid content in Fabry disease: a combined 1H-MR spectroscopy and MR imaging study at 3 Tesla.

    Science.gov (United States)

    Petritsch, B; Köstler, H; Weng, A M; Horn, M; Gassenmaier, T; Kunz, A S; Weidemann, F; Wanner, C; Bley, T A; Beer, M

    2016-10-28

    Fabry disease is characterized by a progressive deposition of sphingolipids in different organ systems, whereby cardiac involvement leads to death. We hypothesize that lysosomal storage of sphingolipids in the heart as occurring in Fabry disease does not reflect in higher cardiac lipid concentrations detectable by 1 H magnetic resonance spectroscopy (MRS) at 3 Tesla. Myocardial lipid content was quantified in vivo by 1 H-MRS in 30 patients (12 male, 18 female; 18 patients treated with enzyme replacement therapy) with genetically proven Fabry disease and in 30 healthy controls. The study protocol combined 1 H-MRS with cardiac cine imaging and LGE MRI in a single examination. Myocardial lipid content was not significantly elevated in Fabry disease (p = 0.225). Left ventricular (LV) mass was significantly higher in patients suffering from Fabry disease compared to controls (p = 0.019). Comparison of patients without signs of myocardial fibrosis in MRI (LGE negative; n = 12) to patients with signs of fibrosis (LGE positive; n = 18) revealed similar myocardial lipid content in both groups (p > 0.05), while the latter showed a trend towards elevated LV mass (p = 0.076). This study demonstrates the potential of lipid metabolic investigation embedded in a comprehensive examination of cardiac morphology and function in Fabry disease. There was no evidence that lysosomal storage of sphingolipids influences cardiac lipid content as measured by 1 H-MRS. Finally, the authors share the opinion that a comprehensive cardiac examination including three subsections (LGE; 1 H-MRS; T 1 mapping), could hold the highest potential for the final assessment of early and late myocardial changes in Fabry disease.

  6. The Combined Effect of Subjective Body Image and Body Mass Index (Distorted Body Weight Perception on Suicidal Ideation

    Directory of Open Access Journals (Sweden)

    Jaeyong Shin

    2015-03-01

    Full Text Available Objectives: Mental health disorders and suicide are an important and growing public health concern in Korea. Evidence has shown that both globally and in Korea, obesity is associated with an increased risk of developing some psychiatric disorders. Therefore, we examined the association between distorted body weight perception (BWP and suicidal ideation. Methods: Data were obtained from the 2007-2012 Korea National Health and Nutritional Evaluation Survey (KNHANES, an annual cross-sectional nationwide survey that included 14 276 men and 19 428 women. Multiple logistic regression analyses were conducted to investigate the associations between nine BWP categories, which combined body image (BI and body mass index (BMI categories, and suicidal ideation. Moreover, the fitness of our models was verified using the Akaike information criterion. Results: Consistent with previous studies, suicidal ideation was associated with marital status, household income, education level, and perceived health status in both genders. Only women were significantly more likely to have distorted BWP; there was no relationship among men. In category B1 (low BMI and normal BI, women (odds ratio [OR], 2.25; 95% confidence interval [CI], 1.48 to 3.42 were more likely to express suicidal ideation than women in category B2 (normal BMI and normal BI were. Women in overweight BWP category C2 (normal BMI and fat BI also had an increased OR for suicidal ideation (OR, 2.25; 95% CI, 1.48 to 3.42. Those in normal BWP categories were not likely to have suicidal ideation. Among women in the underweight BWP categories, only the OR for those in category A2 (normal BMI and thin BI was significant (OR, 1.34; 95% CI, 1.13 to 1.59. Conclusions: Distorted BWP should be considered an important factor in the prevention of suicide and for the improvement of mental health among Korean adults, especially Korean women with distorted BWPs.

  7. Improvement of an infrared/millimeter wave mirror array beam combiner by the wavefront division imaging technique.

    Science.gov (United States)

    Tian, Yi; Sun, Gang; Yan, Hui; Zhang, Li; Li, Zhuo

    2014-10-10

    In order to reduce the complexity of splicing the mirrors of an infrared (IR)/millimeter wave (MMW) beam combiner into a plane, the wavefront division imaging technique (WDIT) was proposed. However, WDIT would lead to the difference of air gap thicknesses among different mirrors, which will further cause the nonuniformity of the MMW field. Simultaneously, there were slots between every two mirrors after the mirror array was spliced and adjusted, which would also affect MMW and IR diffraction. Thus, the aperture field integration method (AFIM) was proposed to compute the MMW near field distribution and the IR far field distribution. The method was validated by comparing the results obtained from the multilevel fast multipole method and experiment. The experimental results showed that the diffraction phenomenon caused by a tilt slot or a hole can approximate that caused by a slot with the width or a hole with the edge diameter along the tilt direction multiplied by cosine of the tilt angle. The variations of both MMW and IR field distributions were caused by three factors: different tilt angles, air gap thicknesses, and slot widths were analyzed by using AFIM in the spatial domain and the time domain. The simulation results showed that the three factors will affect the uniformity of the MMW field. And the uniformity introduced by the air gap thicknesses was the worst. However, the uniformity still satisfied the requirement for phase error when the variation of the air gap thicknesses was less than 1 mm. Although the three factors would cause the loss of energy and an enhancement in the background noise received by an IR focal plane array, the resolution of the IR system would not be affected. Thus, the WDIT was validated through the above analysis.

  8. Combined time-lapse magnetic resonance imaging and modeling to investigate colloid deposition and transport in porous media.

    Science.gov (United States)

    Lehoux, Alizée P; Faure, Pamela; Lafolie, François; Rodts, Stéphane; Courtier-Murias, Denis; Coussot, Philippe; Michel, Eric

    2017-10-15

    Colloidal particles can act as vectors of adsorbed pollutants in the subsurface, or be themselves pollutants. They can reach the aquifer and impair groundwater quality. The mechanisms of colloid transport and deposition are often studied in columns filled with saturated porous media. Time-lapse profiles of colloid concentration inside the columns have occasionally been derived from magnetic resonance imaging (MRI) data recorded in transport experiments. These profiles are valuable, in addition to particle breakthrough curves (BTCs), for testing and improving colloid transport models. We show that concentrations could not be simply computed from MRI data when both deposited and suspended colloids contributed to the signal. We propose a generic method whereby these data can still be used to quantitatively appraise colloid transport models. It uses the modeled suspended and deposited particle concentrations to compute modeled MRI data that are compared to the experimental data. We tested this method by performing transport experiments with sorbing colloids in sand, and assessed for the first time the capacity of the model calibrated from BTCs to reproduce the MRI data. Interestingly, the dispersion coefficient and deposition rate calibrated from the BTC were respectively overestimated and underestimated compared with those calibrated from the MRI data, suggesting that these quantities, when determined from BTCs, need to be interpreted with care. In a broader perspective, we consider that combining MRI and modeling offers great potential for the quantitative analysis of complex MRI data recorded during transport experiments in complex environmentally relevant porous media, and can help improve our understanding of the fate of colloids and solutes, first in these media, and later in soils. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. SU-E-J-87: Lung Deformable Image Registration Using Surface Mesh Deformation for Dose Distribution Combination

    International Nuclear Information System (INIS)

    Labine, A; Carrier, J; Bedwani, S; Chav, R; DeGuise, J

    2014-01-01

    Purpose: To allow a reliable deformable image registration (DIR) method for dose calculation in radiation therapy. This work proposes a performance assessment of a morphological segmentation algorithm that generates a deformation field from lung surface displacements with 4DCT datasets. Methods: From the 4DCT scans of 15 selected patients, the deep exhale phase of the breathing cycle is identified as the reference scan. Varian TPS EclipseTM is used to draw lung contours, which are given as input to the morphological segmentation algorithm. Voxelized contours are smoothed by a Gaussian filter and then transformed into a surface mesh representation. Such mesh is adapted by rigid and elastic deformations to match each subsequent lung volumes. The segmentation efficiency is assessed by comparing the segmented lung contour and the TPS contour considering two volume metrics, defined as Volumetric Overlap Error (VOE) [%] and Relative Volume Difference (RVD) [%] and three surface metrics, defined as Average Symmetric Surface Distance (ASSD) [mm], Root Mean Square Symmetric Surface Distance (RMSSD) [mm] and Maximum Symmetric Surface Distance (MSSD) [mm]. Then, the surface deformation between two breathing phases is determined by the displacement of corresponding vertices in each deformed surface. The lung surface deformation is linearly propagated in the lung volume to generate 3D deformation fields for each breathing phase. Results: The metrics were averaged over the 15 patients and calculated with the same segmentation parameters. The volume metrics obtained are a VOE of 5.2% and a RVD of 2.6%. The surface metrics computed are an ASSD of 0.5 mm, a RMSSD of 0.8 mm and a MSSD of 6.9 mm. Conclusion: This study shows that the morphological segmentation algorithm can provide an automatic method to capture an organ motion from 4DCT scans and translate it into a volume deformation grid needed by DIR method for dose distribution combination

  10. Image guided adaptive brachytherapy with combined intracavitary and interstitial technique improves the therapeutic ratio in locally advanced cervical cancer: Analysis from the retroEMBRACE study

    DEFF Research Database (Denmark)

    LU, Fokdal; Sturdza, Alina; Mazeron, Renaud

    2016-01-01

    Background and purpose Image guided adaptive brachytherapy (IGABT) using intracavitary applicators (IC) has led to a significant improvement of local control in locally advanced cervical cancer (LACC). Further improvement has been obtained with combined intracavitary/interstitial (IC/IS) applicat......Background and purpose Image guided adaptive brachytherapy (IGABT) using intracavitary applicators (IC) has led to a significant improvement of local control in locally advanced cervical cancer (LACC). Further improvement has been obtained with combined intracavitary/interstitial (IC....../IS) applicators. The aim of this analysis was to evaluate the impact on local control and late morbidity of application of combined IS/IC brachytherapy in a large multicentre population. Material/methods 610 patients with LACC from the retroEMBRACE study were included. Patients were divided into an IC group (N...

  11. Combined Whole Body and Multiparametric Prostate Magnetic Resonance Imaging as a 1-Step Approach to the Simultaneous Assessment of Local Recurrence and Metastatic Disease after Radical Prostatectomy.

    Science.gov (United States)

    Robertson, Nicola L; Sala, Evis; Benz, Matthias; Landa, Jonathan; Scardino, Peter; Scher, Howard I; Hricak, Hedvig; Vargas, Hebert A

    2017-07-01

    We report our initial experience with whole body and dedicated prostate magnetic resonance imaging as a single examination to assess local recurrence and metastatic disease in patients with suspected recurrent prostate cancer after radical prostatectomy. In this institutional review board approved, retrospective, single center study 76 consecutive patients with clinically suspected recurrent prostate cancer following radical prostatectomy underwent combined whole body and dedicated prostate magnetic resonance imaging at a single session from October 2014 to January 2016. Scans were evaluated to detect disease in the prostate bed and regional nodes, and at distant sites. Comparison was made to other imaging tests, and prostate bed, node and bone biopsies performed within 90 days. Whole body and dedicated prostate magnetic resonance imaging was completed successfully in all patients. Median prostate specific antigen was 0.36 ng/ml (range less than 0.05 to 56.12). Whole body and dedicated prostate magnetic resonance imaging identified suspected disease recurrence in 16 of 76 patients (21%), including local recurrence in the radical prostatectomy bed in 6, nodal metastases in 3, osseous metastases in 4 and multifocal metastatic disease in 3. In 43 patients at least 1 standard staging scan was done in addition to whole body and dedicated prostate magnetic resonance imaging. Concordance was demonstrated between the imaging modalities in 36 of 43 cases (84%). All metastatic lesions detected by other imaging tests were detected on magnetic resonance imaging. In addition, the magnetic resonance imaging modality detected osseous metastases in 4 patients with false-negative findings on other imaging tests, including 2 bone scans and 3 computerized tomography scans. It also excluded osseous disease in 1 patient with positive 18 F-fluorodeoxyglucose positron emission tomography/computerized tomography and subsequent negative bone biopsy. Combined whole body and dedicated

  12. Combining Diffusion Tensor Metrics and DSC Perfusion Imaging: Can It Improve the Diagnostic Accuracy in Differentiating Tumefactive Demyelination from High-Grade Glioma?

    Science.gov (United States)

    Hiremath, S B; Muraleedharan, A; Kumar, S; Nagesh, C; Kesavadas, C; Abraham, M; Kapilamoorthy, T R; Thomas, B

    2017-04-01

    Tumefactive demyelinating lesions with atypical features can mimic high-grade gliomas on conventional imaging sequences. The aim of this study was to assess the role of conventional imaging, DTI metrics ( p:q tensor decomposition), and DSC perfusion in differentiating tumefactive demyelinating lesions and high-grade gliomas. Fourteen patients with tumefactive demyelinating lesions and 21 patients with high-grade gliomas underwent brain MR imaging with conventional, DTI, and DSC perfusion imaging. Imaging sequences were assessed for differentiation of the lesions. DTI metrics in the enhancing areas and perilesional hyperintensity were obtained by ROI analysis, and the relative CBV values in enhancing areas were calculated on DSC perfusion imaging. Conventional imaging sequences had a sensitivity of 80.9% and specificity of 57.1% in differentiating high-grade gliomas ( P = .049) from tumefactive demyelinating lesions. DTI metrics ( p : q tensor decomposition) and DSC perfusion demonstrated a statistically significant difference in the mean values of ADC, the isotropic component of the diffusion tensor, the anisotropic component of the diffusion tensor, the total magnitude of the diffusion tensor, and rCBV among enhancing portions in tumefactive demyelinating lesions and high-grade gliomas ( P ≤ .02), with the highest specificity for ADC, the anisotropic component of the diffusion tensor, and relative CBV (92.9%). Mean fractional anisotropy values showed no significant statistical difference between tumefactive demyelinating lesions and high-grade gliomas. The combination of DTI and DSC parameters improved the diagnostic accuracy (area under the curve = 0.901). Addition of a heterogeneous enhancement pattern to DTI and DSC parameters improved it further (area under the curve = 0.966). The sensitivity increased from 71.4% to 85.7% after the addition of the enhancement pattern. DTI and DSC perfusion add profoundly to conventional imaging in differentiating tumefactive

  13. Simultaneous Multislice Accelerated Turbo Spin Echo Magnetic Resonance Imaging: Comparison and Combination With In-Plane Parallel Imaging Acceleration for High-Resolution Magnetic Resonance Imaging of the Knee.

    Science.gov (United States)

    Fritz, Jan; Fritz, Benjamin; Zhang, Jialu; Thawait, Gaurav K; Joshi, Dharmdev H; Pan, Li; Wang, Dingxin

    2017-09-01

    We prospectively quantified the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of integrated parallel acquisition technique (PAT) and simultaneous multislice (SMS) acceleration and various combinations thereof, and we further compared two 4-fold-accelerated (PAT2-SMS2) high-resolution turbo spin echo (TSE) magnetic resonance imaging (MRI) protocols of the knee against a clinical 2-fold-accelerated (PAT2-SMS1) TSE standard. Institutional review board approval was obtained, and all subjects gave informed consent. Fourteen knee MRI examinations were obtained (8 men, 6 women; mean age, 46 years; age range, 28-62 years) using a 3 T MRI system and a TSE pulse sequence prototype that allowed for the combination of PAT and SMS acceleration. Predicted whole-body specific absorption rates were recorded for all pulse sequences. For quantitative analysis, the difference method was used to calculate SNR and CNR analysis of 6 different TSE acceleration schemes (PAT2-SMS1, PAT3-SMS1, PAT1-SMS2, PAT1-SMS3, PAT2-SMS2, and PAT2-SMS3). For qualitative analysis, sagittal intermediate-weighted and axial fat-suppressed T2-weighted MR images were obtained with PAT2-SMS1 and PAT2-SMS2 acceleration schemes using similar parameters. One faster PAT2-SMS2 acceleration scheme with decreased repetition time and longer echo train was labeled with the addition SPEED for the purpose of this report. Two readers rated the data sets for image quality, structural visibility, and overall observer satisfaction using equidistant 5-point Likert scales. Readers additionally noted the presence of cartilage defects, meniscal tears, tendons and ligament tears, and bone marrow edema pattern. Friedman and Kruskal-Wallis tests were used. P values of less than 0.01 were considered significant. All pulse sequences were successfully executed and reconstructed inline. Whole-body specific absorption rates ranged between 1.4 and 3.9 W/kg for all acquisitions and remained within mandated limits

  14. Adaptive-optics SLO imaging combined with widefield OCT and SLO enables precise 3D localization of fluorescent cells in the mouse retina.

    Science.gov (United States)

    Zawadzki, Robert J; Zhang, Pengfei; Zam, Azhar; Miller, Eric B; Goswami, Mayank; Wang, Xinlei; Jonnal, Ravi S; Lee, Sang-Hyuck; Kim, Dae Yu; Flannery, John G; Werner, John S; Burns, Marie E; Pugh, Edward N

    2015-06-01

    Adaptive optics scanning laser ophthalmoscopy (AO-SLO) has recently been used to achieve exquisite subcellular resolution imaging of the mouse retina. Wavefront sensing-based AO typically restricts the field of view to a few degrees of visual angle. As a consequence the relationship between AO-SLO data and larger scale retinal structures and cellular patterns can be difficult to assess. The retinal vasculature affords a large-scale 3D map on which cells and structures can be located during in vivo imaging. Phase-variance OCT (pv-OCT) can efficiently image the vasculature with near-infrared light in a label-free manner, allowing 3D vascular reconstruction with high precision. We combined widefield pv-OCT and SLO imaging with AO-SLO reflection and fluorescence imaging to localize two types of fluorescent cells within the retinal layers: GFP-expressing microglia, the resident macrophages of the retina, and GFP-expressing cone photoreceptor cells. We describe in detail a reflective afocal AO-SLO retinal imaging system designed for high resolution retinal imaging in mice. The optical performance of this instrument is compared to other state-of-the-art AO-based mouse retinal imaging systems. The spatial and temporal resolution of the new AO instrumentation was characterized with angiography of retinal capillaries, including blood-flow velocity analysis. Depth-resolved AO-SLO fluorescent images of microglia and cone photoreceptors are visualized in parallel with 469 nm and 663 nm reflectance images of the microvasculature and other structures. Additional applications of the new instrumentation are discussed.

  15. Broader perspectives for comparing different greenhouse gases.

    Science.gov (United States)

    Manning, Martin; Reisinger, Andy

    2011-05-28

    Over the last 20 years, different greenhouse gases have been compared, in the context of climate change, primarily through the concept of global warming potentials (GWPs). This considers the climate forcing caused by pulse emissions and integrated over a fixed time horizon. Recent studies have shown that uncertainties in GWP values are significantly larger than previously thought and, while past literature in this area has raised alternative means of comparison, there is not yet any clear alternative. We propose that a broader framework for comparing greenhouse gases has become necessary and that this cannot be addressed by using simple fixed exchange rates. From a policy perspective, the framework needs to be clearly aligned with the goal of climate stabilization, and we show that comparisons between gases can be better addressed in this context by the forcing equivalence index (FEI). From a science perspective, a framework for comparing greenhouse gases should also consider the full range of processes that affect atmospheric composition and how these may alter for climate stabilization at different levels. We cover a basis for a broader approach to comparing greenhouse gases by summarizing the uncertainties in GWPs, linking those to uncertainties in the FEIs consistent with stabilization, and then to a framework for addressing uncertainties in the corresponding biogeochemical processes. © 2011 The Royal Society

  16. Shale gases, a windfall for France?

    International Nuclear Information System (INIS)

    Tonnac, Alain de; Perves, Jean-Pierre

    2013-11-01

    After having recalled the definition and origin of shale gases, the different non conventional gases and their exploitation techniques (hydraulic fracturing and horizontal drilling) this report examines whether these gases are an opportunity for France. Some characteristics and data of the fossil and gas markets are presented and commented: world primary energy consumption, proved reserves of non conventional gases and their locations, European regions which may possess reserves of shale gases and coal-bed methane, origins of gas imports in France. The second part addresses shale gas deposits and their exploitation: discussion of the influence of the various rock parameters, evolution of production. The third part discusses the exploitation techniques and specific drilling tools. The issue of exploitation safety and security is addressed as well as the associated controversies: about the pollution of underground waters, about the fact that deep drillings result in pollution, about the risks associated with hydraulic fracturing and injections of chemical products, about the hold on ground and site degradation, about water consumption, about pollution due to gas pipeline leakage, about seismic risk, about noise drawbacks, about risks for health, about exploration and production authorization and license, and about air pollution and climate. The last part addresses the French situation and its future: status of the energy bill, recommendations made by a previous government, cancellation of authorizations, etc. Other information are provided in appendix about non conventional hydrocarbons, about shale gas exploitation in the USA, and about the Lacq gas

  17. Scanning electron microscopy combined with image processing technique: Analysis of microstructure, texture and tenderness in Semitendinous and Gluteus Medius bovine muscles.

    Science.gov (United States)

    Pieniazek, Facundo; Messina, Valeria

    2016-11-01

    In this study the effect of freeze drying on the microstructure, texture, and tenderness of Semitendinous and Gluteus Medius bovine muscles were analyzed applying Scanning Electron Microscopy combined with image analysis. Samples were analyzed by Scanning Electron Microscopy at different magnifications (250, 500, and 1,000×). Texture parameters were analyzed by Texture analyzer and by image analysis. Tenderness by Warner-Bratzler shear force. Significant differences (p image and instrumental texture features. A linear trend with a linear correlation was applied for instrumental and image features. Image texture features calculated from Gray Level Co-occurrence Matrix (homogeneity, contrast, entropy, correlation and energy) at 1,000× in both muscles had high correlations with instrumental features (chewiness, hardness, cohesiveness, and springiness). Tenderness showed a positive correlation in both muscles with image features (energy and homogeneity). Combing Scanning Electron Microscopy with image analysis can be a useful tool to analyze quality parameters in meat.Summary SCANNING 38:727-734, 2016. © 2016 Wiley Periodicals, Inc. © Wiley Periodicals, Inc.

  18. Hybrid PET/MR imaging: an algorithm to reduce metal artifacts from dental implants in Dixon-based attenuation map generation using a multiacquisition variable-resonance image combination sequence.

    Science.gov (United States)

    Burger, Irene A; Wurnig, Moritz C; Becker, Anton S; Kenkel, David; Delso, Gaspar; Veit-Haibach, Patrick; Boss, Andreas

    2015-01-01

    It was the aim of this study to implement an algorithm modifying Dixon-based MR imaging datasets for attenuation correction in hybrid PET/MR imaging with a multiacquisition variable resonance image combination (MAVRIC) sequence to reduce metal artifacts. After ethics approval, in 8 oncologic patients with dental implants data were acquired in a trimodality setup with PET/CT and MR imaging. The protocol included a whole-body 3-dimensional dual gradient-echo sequence (Dixon) used for MR imaging-based PET attenuation correction and a high-resolution MAVRIC sequence, applied in the oral area compromised by dental implants. An algorithm was implemented correcting the Dixon-based μ maps using the MAVRIC in areas of Dixon signal voids. The artifact size of the corrected μ maps was compared with the uncorrected MR imaging μ maps. The algorithm was robust in all patients. There was a significant reduction in mean artifact size of 70.5% between uncorrected and corrected μ maps from 697 ± 589 mm(2) to 202 ± 119 mm(2) (P = 0.016). The proposed algorithm could improve MR imaging-based attenuation correction in critical areas, when standard attenuation correction is hampered by metal artifacts, using a MAVRIC. © 2015 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

  19. Cartilage volume quantification with multi echo data image combination sequence in swine knee at 3.0 T MRI

    International Nuclear Information System (INIS)

    Zhang Lirong; Wang Dongqing; Wei Chuanshe; Ma Cong; Wang Dehang

    2010-01-01

    Objective: To investigate the accuracy and reproducibility of multi echo data imagine combination (MEDIC) sequence with water excitation at 3.0 T in swine knee cartilage. Methods: Sagittal MEDIC sequences (0.6 mm slice thickness, isotropic) were acquired twice at 3.0 T MRI in 30 swine knees. The knee cartilage was then removed and the volume was directly measured with water substitution method. The cartilage volume was also determined with a validated open source image software OsiriX by two observers (A and B). The cartilage volumes obtained by two methods were compared. The reproducibility of MEDIC for quantitative measurement was accessed by the root-mean-square (RMS) of variation coefficient. Interobserver and intraobserver precision errors were compared using a paired students t-test. The accuracy of MEDIC for quantitative measurement was determined by the random pairwise differences, systematic pairwise differences and the Pearson, correlation coefficients. Time of semiautomatic and manual segmentation were recorded. Results: Time was saved about 75% by using semiautomatic segmentation methods [(4.0± 1.5) min] versus manual segmentation [(16.0±0.9) min]. Interobserver precision errors (RMS CV% for paired analysis) between A and B for cartilage volume measurement were (2.66±0.82) ml and(2.61± 0.81) ml, t=0.24, P=0.81 (patella); (2.40±0.69) ml and (2.49±0.85) ml, t=-0.45, P=0.65 (medial femoral condyle); (2.28±0.74) ml and(2.41±0.78) ml, t=-0.66, P=0.51 (lateral femoral condyle); (3.43±1.28) ml and (3.51±1.08) ml, t=-0.26, P=0.79 (femora trochlea) with sagittal MEDIC. Intraobserver precision errors (RMS CV% for paired analysis) of observer A for the first and second cartilage volume measurement were (2.64±0.62) ml and (2.67±0.60) ml, t=-0.19, P=0.85 (patella); (2.43±0.60) ml and (2.39±0.59) ml, t=0.26, P=0.80 (medial femoral condyle); (2.26±0.56) ml and (2.30±0.57) ml, t=-0.27, P=0.78 (lateral femoral condyle); (3.40± 1.20) ml and (3.47±1

  20. Design of a Multi-Pinhole Collimator for I-123 DaTscan Imaging on Dual-Headed SPECT Systems in Combination with a Fan-Beam Collimator.

    Science.gov (United States)

    King, Michael A; Mukherjee, Joyeeta M; Könik, Arda; Zubal, I George; Dey, Joyoni; Licho, Robert

    2016-02-01

    For the 2011 FDA approved Parkinson's Disease (PD) SPECT imaging agent I-123 labeled DaTscan, the volume of interest (VOI) is the interior portion of the brain. However imaging of the occipital lobe is also required with PD for calculation of the striatal binding ratio (SBR), a parameter of significance in early diagnosis, differentiation of PD from other disorders with similar clinical presentations, and monitoring progression. Thus we propose the usage of a combination of a multi-pinhole (MPH) collimator on one head of the SPECT system and a fan-beam on the other. The MPH would be designed to provide high resolution and sensitivity for imaging of the interior portion of the brain. The fan-beam collimator would provide lower resolution but complete sampling of the brain addressing data sufficiency and allowing a volume-of-interest to be defined over the occipital lobe for calculation of SBR's. Herein we focus on the design of the MPH component of the combined system. Combined reconstruction will be addressed in a subsequent publication. An analysis of 46 clinical DaTscan studies was performed to provide information to define the VOI, and design of a MPH collimator to image this VOI. The system spatial resolution for the MPH was set to 4.7 mm, which is comparable to that of clinical PET systems, and significantly smaller than that of fan-beam collimators employed in SPECT. With this set, we compared system sensitivities for three aperture array designs, and selected the 3 × 3 array due to it being the highest of the three. The combined sensitivity of the apertures for it was similar to that of an ultra-high resolution fan-beam (LEUHRF) collimator, but smaller than that of a high-resolution fan-beam collimator (LEHRF). On the basis of these results we propose the further exploration of this design through simulations, and the development of combined MPH and fan-beam reconstruction.